DE102017214561B4 - A method of forming a spline in a component using ultra high strength steel - Google Patents

Abstract

A method of forming a spline (4010, 4022) in a component using ultra-high strength steel, comprising the steps of:
Providing a flat blank (14) of ultra-high strength steel (2002) forming the blank into an unfinished shape (1300, 1400, 1500, 1600, 1700) of a component (2004)
Heating the unfinished mold (1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700) of the component (2006); and
Forming a finished mold (1008, 1108, 1208, 1308, 1408, 1508, 1608, 1708) of the spline-containing component using a quenching die having a radially movable segmented tool (5000, 5004).

Description

BACKGROUND

The present disclosure relates to a method of forming splines in components generally made of ultra-high strength steel, such as boron steel.

In the automotive industry, there is a great need for weight reduction of vehicles to increase their efficiency and to reduce fuel consumption. The challenges of meeting fuel economy and CO2 emission goals through the use of lightweight materials and technologies are not only central to the design / structure and engine, but also extend to automatic transmission applications.

Ultra-high strength steel is currently used in structural engineering and static automotive structures (e.g., vehicle bodies and frames). The use of ultra-high strength steel generally allows for a reduction in the weight of these structures. In addition, the ultra-high strength steel in automotive structures enables the absorption of impact energy and minimizes penetration into occupant seating areas. Although ultra high strength steel can be made extremely strong, other properties, such as formability, weldability and impact strength, can be negatively impacted, resulting in structures that are more susceptible to cracking and breakage.

Automatic transmissions use multiple powertrain or "torque-transmitting" components to transfer torque between components. For example, power transmission components for motor vehicles, such as coupling arrangements with clutch plates within a clutch housing and a clutch hub, are well known. Such coupling housings have a generally cylindrical or cup-shaped body and an open end. The cylindrical or cup-shaped body is formed from a sheet metal blank and has a plurality of torque transmitting features formed therein, such as spline teeth. The clutch plates fit into the clutch housing and engage the spline teeth. The clutch hub may also be a formed sheet metal component and is usually connected to a transmission shaft. Powertrain components, including clutch housings and hubs, are typically made of aluminum or high-strength low-alloy steel (HSLA) rather than ultra-high-strength steel such as boron steel. Aluminum or HSLA steel is used primarily because of its formability. In particular, these types of materials are high strength materials that can achieve a certain geometrical dimension and shape and have a certain required tolerance. Consequently, aluminum or HSLA can be used in drive train components including parts of an automatic transmission easily efficiently and at low cost.

Typically, components such as reaction bowls, coupling housings and hubs made of aluminum or HSLA are formed using one or a combination of cold forming or stamping processes and thermal heat treatments to obtain the desired shape, performance and strength properties. In addition, the structures, such as the multiple spline teeth of the clutch housing, can be easily manufactured by using a series of rollers. Similar processes may also be used to form other powertrain components, such as planet carriers used in differentials, and various covers used in a vehicle powertrain.

Ultra-high strength steel lacks moldability using the conventional cold forming technologies discussed above. The use of conventional ultra-high strength steel cold forming technologies typically does not result in the formation of required geometrical dimensions and tolerances. However, for reasons similar to those discussed above for use in static applications of automotive structures (eg, reduced component weight and improved impact energy absorption), there is a desire to provide ultra-high strength steel in the formation of automotive components, such as Example power transmission components to use.

Thus, a requirement for the formation of torque transmitting components, such as clutch housings and hubs, is ultrahigh strength steel, such as boron steel. Moreover, there is a need for an improved method of forming the same. For these reasons, conventional methods of forming torque-transmitting features, such as splines, for co-operating with a heat-assisted calibration (HAC) process, must be developed to effectively and completely form the features for proper co-operation with Permit passport components.

From the WO 2015 143 537 A1 shows a method for producing ultra-high strength steel components made from a flat blank. This unfinished shapes are formed from the blank. The unfinished shape of the component is heated and then the finished mold is formed, which includes a spline.
From the DE 4103 33 166 A1 is a method for the production of press-hardened components known. In this case, a semi-finished product is deformed by a cold forming process, the component is heated and press-hardened to a hot-forming tool.

From the EP 2 848 709 A1 It is known to form a steel component warm and then to harden.

From the EP 2 429 733 B1 discloses a method of manufacturing a component of a synchronizer that is made by hot working, wherein partial areas are heated and reshaped with lasers.

From the WO 2205 021 821 A1 For example, there is known a method of manufacturing sheet steel components which is heated for hot working and cooled in a mold hardening tool.

Based on the prior art, it is the object of the invention to improve a method of forming a spline in a component using ultra high strength steel. This object is achieved with the features of claim 1.

SUMMARY

This section provides a general summary of the inventive concepts of the present disclosure and is not intended to be a comprehensive disclosure of its full scope or all of its features, subject, aspects, and advantages. Ultra high strength steel formed components and a process for forming these ultra high strength steel components are provided.

According to one aspect of the present disclosure, a method of forming a component using ultra-high-strength steel includes the steps of providing a flat blank of ultra high-strength steel. The process proceeds to form the flat blank into an unfinished form of a component. Next, the method includes the steps of providing an atmosphere, preferably an inert atmosphere, and heating the unfinished form of the component in the inert atmosphere. Then forming a finished shape of the component using a quenching die with a radially movable segmented tool

According to one aspect of the present disclosure, an ultra high strength steel component is manufactured by providing a flat blank of ultra high strength steel. Next, forming the flat blank into an unfinished shape of the component. This is followed by heating the unfinished form of the component. Alternatively, the previous forming step may be followed by providing an inert atmosphere and heating the unfinished form of the component in the inert atmosphere. Then forming a finished mold of the component using a quenching die with a radially movably segmented tool to obtain the component.

According to an embodiment of a component made according to the present disclosure, a clutch housing is provided. The coupling housing has a cylindrical or cup-shaped body and an open end.

According to this embodiment of the present disclosure, a method of forming the ultra-high-strength steel coupling housing includes cold-forming the body of the coupling housing, heat-treating in an inert atmosphere, and quenching using a water-cooled quenching die to form and finish the cylindrical or cup-shaped body. The ultra-high-strength steel forming the body of the clutch housing may be boron steel.

According to this embodiment of the present disclosure, the method of forming ultra high strength steel components includes preforming or cold forming a flat steel blank into a predetermined shape. The predetermined shape may be a cylindrical or cup-shaped body. The step of cold forming the flat steel blank may include forming a plurality of spline teeth along the steel blank. The method may also include heat treating the steel blank in an inert atmosphere. The inert atmosphere may be an induction furnace or an induction chamber. In addition, heat treatment may be partially or completely localized. Further, the method includes quenching the heat treated steel blank. Quenching may include forming a plurality of spline teeth along the steel blank or completing the predetermined shape using a water-cooled quenching die.

According to this embodiment of the present disclosure, the method includes forming ultra high strength steel components Heat treating a steel blank in an inert atmosphere and quenching the heat treated blank to a predetermined shape.

According to another embodiment of a component made in accordance with the present disclosure, a clutch hub is provided. The clutch hub has a cup-shaped body and an open end.

In yet another embodiment of a component made in accordance with the present disclosure, a planet carrier is provided. The planet carrier comprises a first part and a second part, which are joined together by a weld. The first part contains a plurality of legs which extend in the longitudinal direction. A plurality of apertures are disposed around the circumference of each part in a spaced-apart relationship.

In yet another embodiment of a component made according to the present disclosure, a reaction shell is provided. The reaction bowl comprises a body containing a cylindrical first portion having a first diameter and a cylindrical second portion having a second diameter greater than the first diameter. A plurality of radially outwardly extending spline teeth are disposed about the cylindrical second portion.

According to one aspect of the disclosure, methods for forming features of a component are also provided.

The aspects disclosed herein offer several advantages. For example, due to a reduced cross-section resulting from increased material strength, the components are more conventional components than HSLA steel using. The components have an increased tolerance by using ultra-high strength steel over conventional components. The process is more cost effective and reduces costs due to trimming of the components using water cooled quenching in contrast to conventional processes which require additional trimming such as laser trimming. In other words, there is reduced wear and reduced maintenance based on the resulting lower cutting forces through the use of water-cooled quenching. In addition, there is improved component reliability due to the reduction of crack initiation due to soft component trimming and increased manufacturing flexibility through the use of localized induction heating.

Another aspect of the present disclosure is the provision of a spline forming process used in conjunction with ultra-high strength steel and HAC (HAC) heat transfer assisted (HAC) processing.

To overcome deficiencies known in the art, the spline forming methods of the present disclosure are configured to use tools that are movable with respect to the outside diameter and / or inside diameter of the torque transmitting components. The solution focuses on movement of the tool segments to form spline teeth and / or other complex geometries on the component. All such splines and features are formed simultaneously using tool segments that are positioned to completely surround and encompass the components. These components can be made from round or rectangular blanks or pre-machined forgings by "swaging". In addition, flat or formed blanks may also be used prior to HAC processing.

list of figures

• 1 ist eine perspektivische Ansicht eines Kupplungsgehäuses und einer Kupplungsnabe gemäß einem Ausführungsbeispiel der vorliegenden Offenbarung;
• 2 ist eine Querschnittsansicht entlang 2-2 von 1;
• 3 ist eine perspektivische Ansicht eines Kupplungsgehäuses mit mehreren Keilverzahnungszähnen zur Ineingriffnahme einer Kupplungsplatte gemäß dem Ausführungsbeispiel der vorliegenden Offenbarung;
• 4 ist ein Flussdiagramm eines Verfahrens zur Herstellung einer Kraftübertragungskomponente unter Verwendung von ultrahochfestem Stahl gemäß dem Ausführungsbeispiel der vorliegenden Offenbarung;
• 5 ist ein Flussdiagramm eines Verfahrens zur Herstellung einer Kraftübertragungskomponente unter Verwendung von ultrahochfestem Stahl gemäß dem Ausführungsbeispiel der vorliegenden Offenbarung;
• 6 ist ein Flussdiagramm eines Verfahrens zur Herstellung einer Kraftübertragungskomponente unter Verwendung von ultrahochfestem Stahl gemäß dem Ausführungsbeispiel der vorliegenden Offenbarung;
• 7 ist ein Flussdiagramm eines Verfahrens zur Herstellung einer Kraftübertragungskomponente unter Verwendung von ultrahochfestem Stahl gemäß dem Ausführungsbeispiel der vorliegenden Offenbarung;
• 8 ist eine perspektivische Ansicht einer Kupplungsnabe gemäß einer zweiten Ausführungsform der vorliegenden Offenbarung;
• 9 ist eine perspektivische Ansicht eines CVT-Stößels (CVT - Continuously Variable Transmission / stufenloses Getriebe) gemäß einer dritten Ausführungsform der vorliegenden Offenbarung;
• 10 ist eine perspektivische Ansicht eines CVT-Zylinders gemäß einer vierten Ausführungsform der vorliegenden Offenbarung;
• 11 ist eine perspektivische Ansicht eines Planetenträgers gemäß einer fünften Ausführungsform der vorliegenden Offenbarung;
• 12A ist eine Seitenansicht einer Reaktionsschale gemäß einer sechsten Ausführungsform der vorliegenden Offenbarung;
• 12B ist eine perspektivische Ansicht einer Reaktionsschale gemäß der sechsten Ausführungsform der vorliegenden Offenbarung;
• 13 ist eine Seitenansicht einer gemäß der Offenbarung hergestellten ersten Reaktionsschale;
• 14A ist eine perspektivische Ansicht einer gemäß der Offenbarung hergestellten zweiten Reaktionsschale;
• 14B ist eine vergrößerte Teilansicht der zweiten Reaktionsschale von 14A;
• 14C ist eine Querschnittsansicht der zweiten Reaktionsschale von 2A;
• 15A ist eine perspektivische Teilansicht einer gemäß der Offenbarung hergestellten dritten Reaktionsschale;
• 15B ist eine vergrößerte Teilansicht der dritten Reaktionsschale von 15A;
• 16A ist eine Seitenansicht der ersten Reaktionsschale von 1;
• 16B ist eine Querschnittsansicht der ersten Reaktionsschale von 1;
• 17A - 17F zeigen ein Verfahren zum Bilden einer Komponente gemäß der Offenbarung, das in Querschnittsansichten der ersten Reaktionsschale entlang I-I von 16B dargestellt ist;
• 18A - 18E zeigen ein Verfahren zum Bilden einer Komponente gemäß der Offenbarung, das mit Querschnittsansichten der ersten Reaktionsschale entlang I-I von 16B dargestellt ist;
• 19A - 19E zeigen ein Verfahren zum Bilden einer Komponente gemäß der Offenbarung, das mit Querschnittsansichten der ersten Reaktionsschale entlang I-I von 16B dargestellt ist;
• 20A -20E zeigen ein Verfahren zum Bilden einer Komponente gemäß der Offenbarung, das mit Querschnittsansichten der ersten Reaktionsschale entlang I-I von 16B dargestellt ist;
• 21A - 21E zeigen ein Verfahren zum Bilden einer Komponente gemäß der Offenbarung, das mit Querschnittsansichten der ersten Reaktionsschale entlang I-I von 16B dargestellt ist;
• 22A - 22E zeigen ein Verfahren zum Bilden einer Komponente gemäß der Offenbarung, das mit Querschnittsansichten der ersten Reaktionsschale entlang I-I von 16B dargestellt ist;
• 23A - 23E zeigen ein Verfahren zum Bilden einer Komponente gemäß der Offenbarung, das mit Querschnittsansichten der ersten Reaktionsschale entlang I-I von 16B dargestellt ist;
• 24A - 24E zeigen ein Verfahren zum Bilden einer Komponente gemäß der Offenbarung, das mit Querschnittsansichten der ersten Reaktionsschale entlang I-I von 16B dargestellt ist;
• 25A ist eine Teilquerschnittsansicht eines gemäß der Offenbarung hergestellten Kupplungsgehäuses;
• 25B ist eine vergrößerte Teilquerschnittsansicht des Kupplungsgehäuses von 25A, die einen Kupplungsbetätigungshebel darstellt;
• 25C ist eine perspektivische Ansicht des Kupplungsgehäuses von 25A;
• 25D ist eine Teilquerschnittsansicht entlang II-II von 25A, die mehrere Kupplungsplatten, den Kupplungsbetätigungshebel und eine im Kupplungsgehäuse angeordnete Kupplungskugelrampe darstellt;
• 26 ist eine schematische Darstellung eines Keilverzahnungsbildungsprozesses für Drehmomentübertragungskomponenten, der die Lehren der vorliegenden Offenbarung darstellt;
• 27A - 27D stellen eine AD-Keilverzahnungsbildungsalternative für den in 26 gezeigten Prozess dar;
• 28 ist eine schematische Darstellung eines anderen Keilverzahnungsbildungsprozesses für Drehmomentübertragungskomponenten, der auch die Lehren der vorliegenden Offenbarung darstellt;
• 29A - 29D stellen ID- und AD- Keilverzahnungsbildungsalternativen für den in 28 gezeigten Prozess dar;
• 30 stellt einen Teil einer Drehmomenübertragungskomponente mit einer durch einen Abstreckziehprozess gebildeten Keilverzahnung dar;
• 31 stellt einen Teil einer Drehmomentübertragungskomponente mit einer durch einen Nockengesenkprozess gebildeten Keilverzahnung dar;
• 32 stellt eine Reihe von Ansichten für einen Nockengesenkkeilverzahnungsbildungsprozess dar, der für jegliche der mit der vorliegenden Offenbarung verbundenen ID- und AD-Keilverzahnungsbildungsalternativen eingesetzt werden kann;
• 33 stellt eine Reihe von Ansichten für AD-Bildungsalternativen zur Keilverzahnungsbildung unter Verwendung eines Walzformwerkzeugprozesses dar;
• 34 stellt zusätzliche mit dem Walzformwerkzeugkeilverzahnungsbildungsprozess verbundene Ansichten dar;
• 35A - 35C stellen eine Reihe von mit einem HAC-Walzformwerkzeugkeilverzahnungsbildungsprozess, der die Lehren der vorliegenden Offenbarung darstellt, verbundene Ansichten dar.

The disclosure is best understood from the following detailed description when read in conjunction with the accompanying drawings. It should be emphasized that, according to common practice, the various features of the drawings are not to scale. On the contrary, for the sake of clarity, the dimensions of the various features are arbitrarily increased or reduced.

• 1 FIG. 12 is a perspective view of a clutch housing and a clutch hub according to an embodiment of the present disclosure; FIG.
• 2 is a cross-sectional view along 2-2 of 1 ;
• 3 FIG. 12 is a perspective view of a clutch housing having a plurality of spline teeth for engaging a clutch plate according to the embodiment of the present disclosure; FIG.
• 4 FIG. 10 is a flowchart of a method of manufacturing a power transmission component using ultra-high strength. FIG Steel according to the embodiment of the present disclosure;
• 5 FIG. 10 is a flowchart of a method of manufacturing a power transmission component using ultra-high strength steel according to the embodiment of the present disclosure; FIG.
• 6 FIG. 10 is a flowchart of a method of manufacturing a power transmission component using ultra-high strength steel according to the embodiment of the present disclosure; FIG.
• 7 FIG. 10 is a flowchart of a method of manufacturing a power transmission component using ultra-high strength steel according to the embodiment of the present disclosure; FIG.
• 8th FIG. 13 is a perspective view of a clutch hub according to a second embodiment of the present disclosure; FIG.
• 9 FIG. 12 is a perspective view of a continuously variable transmission (CVT) CVT according to a third embodiment of the present disclosure; FIG.
• 10 FIG. 15 is a perspective view of a CVT cylinder according to a fourth embodiment of the present disclosure; FIG.
• 11 FIG. 10 is a perspective view of a planetary carrier according to a fifth embodiment of the present disclosure; FIG.
• 12A FIG. 10 is a side view of a reaction shell according to a sixth embodiment of the present disclosure; FIG.
• 12B FIG. 12 is a perspective view of a reaction shell according to the sixth embodiment of the present disclosure; FIG.
• 13 FIG. 10 is a side view of a first reaction shell made in accordance with the disclosure; FIG.
• 14A FIG. 12 is a perspective view of a second reaction cup made in accordance with the disclosure; FIG.
• 14B is an enlarged partial view of the second reaction shell of 14A ;
• 14C is a cross-sectional view of the second reaction shell of 2A ;
• 15A is a partial perspective view of a third reaction shell prepared according to the disclosure;
• 15B is an enlarged partial view of the third reaction shell of 15A ;
• 16A is a side view of the first reaction shell of 1 ;
• 16B is a cross-sectional view of the first reaction shell of 1 ;
• 17A - 17F show a method for forming a component according to the disclosure, which in cross-sectional views of the first reaction shell along II of 16B is shown;
• 18A - 18E show a method of forming a component according to the disclosure, with cross-sectional views of the first reaction shell along II of FIG 16B is shown;
• 19A - 19E show a method of forming a component according to the disclosure, with cross-sectional views of the first reaction shell along II of FIG 16B is shown;
• 20A - 20E show a method of forming a component according to the disclosure, with cross-sectional views of the first reaction shell along II of FIG 16B is shown;
• 21A - 21E show a method of forming a component according to the disclosure, with cross-sectional views of the first reaction shell along II of FIG 16B is shown;
• 22A - 22E show a method of forming a component according to the disclosure, with cross-sectional views of the first reaction shell along II of FIG 16B is shown;
• 23A - 23E show a method of forming a component according to the disclosure, with cross-sectional views of the first reaction shell along II of FIG 16B is shown;
• 24A - 24E show a method of forming a component according to the disclosure, with cross-sectional views of the first reaction shell along II of FIG 16B is shown;
• 25A FIG. 4 is a partial cross-sectional view of a clutch housing made in accordance with the disclosure; FIG.
• 25B is an enlarged partial cross-sectional view of the clutch housing of 25A representing a clutch operating lever;
• 25C is a perspective view of the coupling housing of 25A ;
• 25D is a partial cross-sectional view along II-II of 25A a plurality of clutch plates, the clutch operating lever and a coupling ball ramp arranged in the clutch housing;
• 26 FIG. 12 is a schematic illustration of a spline forming process for torque transmitting components embodying the teachings of the present disclosure; FIG.
• 27A - 27D provide an AD spline forming alternative for the in 26 shown process;
• 28 FIG. 12 is a schematic illustration of another spline forming process for torque transmitting components, which also illustrates the teachings of the present disclosure; FIG.
• 29A - 29D provide ID and AD spline forming alternatives for the in 28 shown process;
• 30 illustrates a portion of a torque transmission component having a spline formed by an ironing process;
• 31 represents a part of a torque transmitting component with a spline formed by a cam die process;
• 32 Fig. 12 illustrates a number of views for a cam die formation process that may be used for any of the ID and AD spline formation alternatives associated with the present disclosure;
• 33 Fig. 12 illustrates a series of views for AD forming alternatives for spline formation using a roll forming process;
• 34 illustrates additional views associated with the roll forming tool gearing process;
• 35A - 35C illustrate a series of views associated with a HAC roll forming tool spline forming process embodying the teachings of the present disclosure.

DETAILED DESCRIPTION

Detailed examples of the present disclosure are disclosed herein; however, it should be understood that the examples disclosed are merely exemplary and can be embodied in various and alternative forms. It is not intended that these examples illustrate and describe all possible forms of disclosure, but rather that the terms used in the specification are illustrative rather than limiting, and it is to be understood that various changes may be made without departing from the spirit and the art Scope of the disclosure deviate.

The aspects disclosed herein include components made of ultra high strength steel and a method of forming components using ultra high strength steel. In particular, the components may be, for example, light hubs and housings of an automatic clutch, planetary gear or torque converter cover made of boron steel and cold worked in its uncured state via an "indirect process" near net shape and finished, ie, heat assisted calibration (HAC - Heat Assisted Calibration) get their final contour to a rotation inertia mass reduction of 40 to reach 60%. In one aspect, the lightweight preformed boron steel components (with or without multiple spline teeth) are subsequently heated in an inert atmosphere and rapidly transferred to a water-cooled quench die to minimize oxidation, resulting in a fine-grained martensitic component material structure. The quench tool allows for final contour machining within geometric dimensions and tolerance requirements. A related aspect uses a spline forming process in combination with the HAC process to form high strength spline teeth in their final contour.

As one of ordinary skill in the art appreciates, various features of the present disclosure, as illustrated and described with reference to any of the figures, may be combined with features illustrated in one or more other figures to provide examples of the present disclosure which are not explicitly shown and described. The combinations of illustrated features provide representative examples of typical applications. However, various combinations and modifications of the features in accordance with the teachings of the present disclosure may be desired for particular applications or implementations.

Embodiments of components made of ultra-high strength steel according to the present disclosure will now be described in more detail. These embodiments are primarily directed to powertrain components. Each of the embodiments is further provided so that this disclosure is thorough and provides those skilled in the art with the scope of the inventive concepts, features, and advantages. To this end, numerous specific details are given to provide a thorough understanding of each of the present disclosure to ensure related embodiments. However, it will be apparent to those skilled in the art that not all specific details described herein are to be utilized, that embodiments may be embodied in many different forms, and that neither should be construed or interpreted as limiting the scope of the disclosure.

The 1-3 show different views of a clutch housing 10 according to an embodiment of the present disclosure. In particular shows 1 a perspective view of a coupling housing 10 ; 2 shows a cross-sectional view of the coupling housing 10 and the hub 12 ; and 3 shows a perspective view of the coupling housing 10 with a plurality of spline teeth arranged thereon 16 , In the 1 and 2 becomes the clutch housing 10 without the multiple spline teeth 16 shown. The coupling housing 10 has a generally cylindrical or cup-shaped configuration with a radial ring portion 12 and a cylindrical drum part 15 on. The coupling housing 10 is from a band 14 (ie blank) made of ultra high strength steel; a preferred type of ultra-high strength steel comprises 22MnB5 boron steel. The ultra-high strength steel may be precoated with aluminum-silicon (AISi) or other material to prevent corrosion and decarburization during the heating and quenching steps. The coupling housing 10 may be a single part or consist of two parts that are joined together by a weld or may be press-formed. For the production of the coupling housing 10 becomes a Borstahlrohling 14 preformed to a predetermined shape, in particular cold-formed. The predetermined shape may be a cylindrical shape or any shape known in the related art to clutch housings. After cold forming the blank 14 to a predetermined shape, the predetermined shape is heat-treated in an inert environment. The inert environment may be an induction furnace or an induction chamber. Heat treatment may include, but is not limited to, annealing, case hardening, annealing, quenching, thermoforming, or welding, or a combination thereof. Next is the clutch housing 10 applied by a water-cooled quenching tool to a plurality of spline teeth 16 to form on it, as in 3 shown.

Alternatively, the water-cooled quenching tool may be used instead of a plurality of spline teeth 16 form a second predetermined shape, as in the 1-2 shown at the clutch housing 10 is smooth. It is important in 2 to point out that the cross-sectional view shows a reduction of the materials used compared to conventional methods using HSLA steel. A clutch hub can be made in the same manner as described below.

With reference to 4 1, a flowchart of a method of forming a component using ultra high strength steel according to the embodiment of the present disclosure is provided. As illustrated by additional embodiments described in greater detail below, the component may be, but is not limited to, a clutch housing, a clutch hub, a planet carrier, or a torque converter cover. In the embodiment, the component is the above-described coupling housing 10 , Initially, the method comprises the first step 100 preforming a flat steel blank into a predetermined shape, the plurality of spline teeth 16 having. In particular, preforming of the flat steel blank is performed by cold forming techniques. The predetermined or unfinished form is based on the nature of the component. For example, if the component is a clutch housing 10 is the steel can be cold formed into a cylindrical or cup-shaped shape. The flat steel blank may be 22MnB5 boron steel and may be precoated to prevent corrosion. After preforming the flat steel blank into a predetermined shape with the plurality of spline teeth 16 the preformed predetermined shape is heat treated in an inert atmosphere, second step 102 to change the properties of the steel. Then, the heat-treated steel is dimensioned and calibrated using a quenching tool, as by step 104 displayed. In particular, a water-cooled quenching tool is used for the sizing / calibration process.

With reference to 5 A flowchart is provided with a method of manufacturing a component using ultra-high strength steel according to the embodiment of the present disclosure. The method includes the step 200 preforming a flat steel blank into a cup-shaped body. As discussed above, the flat steel blank may be a 22MnB5 boron steel blank. Then the cup-shaped body becomes 202 heat treated in an inert environment. The inert environment may be an induction chamber or an induction furnace. Next, the method at 204 water-cooled quenching of the cup-shaped body to form a plurality of spline teeth thereon.

The 6-7 Also, flowcharts of methods for forming a component using ultra-high strength steel according to the present invention are shown in FIG Embodiment of the present disclosure. Like the ones in the 4-5 The methods used in the 6-7 22MnB5 boron steel shown. However, it will be apparent to those skilled in the art that any type of ultra-high strength steel or type of boron steel may be used in conjunction with these methods. In 6 the method comprises the step 300 preforming or cold forming the flat steel blank into a predetermined shape. The predetermined or unfinished form of in 6 shown method does not contain multiple spline teeth 16 , The cold-formed steel is then in step 302 heat treated in an inert atmosphere. The heat treatment can be localized to a specific part of the steel. Furthermore, the method comprises step 304 forming a plurality of spline teeth 16 in the heat-treated steel using a quenching die. The quenching tool is a water-cooled quenching die.

On 7 Referring to FIG. 1, the method of manufacturing a component using ultra high strength steel according to the embodiment of the present disclosure includes the step 400 heat treating a flat steel blank in an inert atmosphere and the step 402 quenching the heat-treated flat blank into a predetermined shape using a quenching tool.

The method discussed above may also be cold forming the coupling housing 10 without multiple spline teeth 16 , Heat treating the unfinished form of the coupling housing 10 using localized induction heating and forming and sizing the plurality of spline teeth 16 using the quenching die, but is not limited thereto. Alternatively, the method may include preforming / cold forming the coupling housing 10 with multiple spline teeth 16 , Heating the unfinished form of the clutch housing 10 in an inert environment and dimensioning and finishing the shape of the coupling housing 10 in the quenching die. Likewise, the planetary gear carriers and other components may be partially or completely cold formed and then heated using either localized or complete part heating.

In addition to the clutch housing disclosed above 10 For example, other embodiments of ultra high strength steel components made in accordance with the present disclosure will be described in more detail below. 8th shows a clutch hub 500 according to a second embodiment of the present disclosure. The clutch hub 500 has a cup-shaped shape with a radial ring part 502 and a cylindrical drum part 504 on. A tubular neck 506 extends in the longitudinal direction of the radial ring member 502 , and a drive gear 508 is on the tubular neck 506 attached. Like the clutch housing 10 can the clutch hub 500 be made of a band (ie, a blank) of ultra high strength steel. The ultra-high strength steel may also be precoated with aluminum-silicon (AISi) or other material to prevent corrosion and decarburization during the heating and quenching steps. The clutch hub 500 may be a single part or consist of two parts that are joined together by a weld or may be press-formed. For the production of the clutch hub 500 For example, a boron steel blank may be cold formed to a predetermined or unfinished shape. Several generally triangular openings 510 can be formed during cold forming for weight reduction in the radial ring part. The predetermined shape may then be heat treated in an inert environment. Next, the clutch hub 500 with a water-cooled quenching tool about a plurality of radially outwardly extending spline teeth 512 to form around the cylindrical drum part 504 are arranged.

9 shows a continuously variable transmission (CVT) CVT 520 according to a third embodiment of the present disclosure. The CVT tappet 520 includes a generally bell-shaped body having a centrally located opening 522 Are defined. The CVT tappet 520 is made from a preformed flat blank of ultra-high strength steel, preferably 22MnB5 boron steel. The boron steel blank can be cold formed into a predetermined or unfinished shape with thick center and thick outer edge. The predetermined shape may then be heat treated in an inert environment. Next up is the CVT tappet 520 be acted upon by a water-cooled quenching tool.

10 shows a CVT cylinder 540 according to a fourth embodiment of the present disclosure. The CVT cylinder 540 includes an annular or cylindrically shaped body having a first end 542 and a second end 544 and one at the first end 542 trained shoulder 546 , The body of the CVT cylinder 540 defines an opening 548 extending lengthwise from the first end 542 to the second end 544 runs. The CVT cylinder 540 begins as a preformed flat blank of ultra-high strength steel, preferably 22MnB5 boron steel, with centered material removed and discarded. Next, the preformed blank or unfinished form is heat treated in an inert environment. Then the CVT cylinder 540 acted upon by a water-cooled quenching tool.

11 shows a planet carrier 560 according to a fifth embodiment of the present disclosure. The planet carrier 560 includes a first part 562 and a second part 564 , which are joined together by a weld. Several breakthroughs 566 are in a spaced relation to each other around the circumference of each part 562 . 564 arranged. The first part 562 contains several thighs 568 which extend in the longitudinal direction. To the formation of the first part 562 of the planet carrier 560 For example, a flat boron steel blank may become a predetermined or unfinished shape with the plurality of apertures 566 and the thighs 568 having cold-formed. To form the second part 564 of the planet carrier 560 For example, a flat boron steel blank can become an unfinished mold with multiple breakthroughs 566 cold formed. The unfinished shapes of the parts 562 . 564 are heat treated in an inert environment. Next, every part 562 . 564 of the planet carrier 560 be acted upon by a water-cooled quenching tool. The planet carrier 560 is by joining or welding the legs 568 of the first part 562 with the second part 564 completed.

The 12A and 12B show two reaction dishes 580 according to a sixth embodiment of the present disclosure. Every reaction bowl 580 includes a body having a cylindrical first part 582 with a first diameter and a cylindrical second part 584 with a second diameter larger than the first diameter. A plurality of radially outwardly extending spline teeth 586 are around the cylindrical second part 584 arranged. Several holes 588 be through the cylindrical first part 582 and the cylindrical second part 584 Are defined. To form the reaction shell 580 For example, a flat boron steel blank is cold formed into a predetermined tubular shape or unfinished shape with the bores. The predetermined tubular shape is then heat treated in an inert environment. Although the holes 588 are formed during cold forming, it is understood that the holes 588 can also be formed while the predetermined tubular shape is hot. Next, the reaction bowl is impacted by a water cooled chill tool to hold the geometry and around the cylindrical second part 584 arranged, radially outwardly extending spline teeth 586 to build. As detailed, the spline teeth 586 be formed before the quenching of the tool.

13A . 14A - 14C . 15A - 15B and 16A - 16B show different views of the reaction dishes 700 . 800 . 900 , which are similar in accordance with embodiments of the present disclosure in accordance with embodiments of the present disclosure 12A and 12B are produced shown. Such reaction dishes 700 . 800 . 900 For example, they could be used as part of a planetary gear arrangement in a transmission. In particular shows 13 a side view of a first reaction shell 700 . 14A shows a perspective view of a second reaction shell 800 . 14B is an enlarged view of part of the second reaction shell 800 , and 14C shows a cross-sectional view of the second reaction shell 800 , 15A is a partial perspective view of a third reaction tray 900 , and 15B is an enlarged view of part of the third reaction shell 900 , 16A shows the first reaction shell 700 that also in 13 is shown, and 16B shows a cross-sectional view of the first reaction shell 700 , Every reaction bowl 700 . 800 . 900 includes a body 702 . 802 . 902 with a proximal end 704 . 804 . 904 and a distal end 706 . 806 . 906 , and can have a shoulder defined in between 708 . 808 contain. Similar to the reaction dishes 580 , referring to the above 12A and 12B have been described, the body can 702 . 802 . 902 also a cylindrical first part 710 . 810 with a first diameter extending from the proximal end 704 . 804 to the shoulder 708 . 808 extends, and a cylindrical second part 712 . 812 with a second diameter larger than the first diameter extending from the shoulder 708 . 808 to the distal end 706 . 806 extends, included.

Now on the first reaction shell 700 and the second reaction shell 800 Referring to, the shoulder defines 708 . 808 of the body 702 . 802 a first flange 714 . 814 that is from the first part 710 . 810 radially outwardly to the second diameter of the second part 712 . 812 extends. The first part 810 of the body 802 can be at the proximal end 804 a radially inwardly extending second flange 816 contain ( 14A) , The second flange 816 can also have several slots 818 or lock connection windows define around the perimeter of the second flange 816 for engagement with a carrier ( 14C) are spaced. Several first holes 719 . 819 are to reduce mass and / or balance around the perimeter of the first part 710 . 810 arranged and defined by him. Likewise, the first flange 814 also several elongated shoulder holes 820 define that are arranged around the circumference.

How best in the 14A and 14C shown, the second part defines 812 of the body 802 the second reaction shell 800 a plurality of radially outwardly extending spline teeth 822 that are around there next to the distal end 806 are arranged. The spline teeth 822 should a transmission component of a transmission ( 14C) engage. There may also be several triangular holes 724 . 824 around the perimeter of the second part 712 . 812 be arranged and defined by him. Likewise, the second part 712 . 812 of the body 702 . 802 also speed sensor holes 826 ( 14A) For example, they are circumferentially arranged for use in conjunction with an optical or Hall effect velocity sensor.

How best in 15A shown, defines the body 902 the third reaction shell 900 also a plurality of radially extending splines teeth 922 that are around there next to the distal end 908 are arranged. In addition, the third reaction shell defines 900 multiple spline holes 928 ( 15B) around the circumference of the body 902 are arranged and radially by a selection of the spline teeth 922 run ( 15B) , A snap ring groove 930 is through an inner surface of the spline teeth 922 Are defined ( 15B) ,

To form each of the reaction dishes 700 . 800 . 900 or other components, several "heat-assisted calibration steps" (HAC steps) may be used, as described below.

The in the 17A - 24E The methods depicted and described in detail below include more specific process steps for forming specific features (eg, bores, tabs, etc.) of a component, such as the reaction shells 700 . 800 . 900 but not limited to this.

Again on the 14A and 14B Referring to FIGS., Portions of the second flange may be 816 of the body 802 the second reaction shell 800 between the slots 818 Be "thickened". As discussed in more detail below, this can be the reaction shell 800 forming material in the middle of the slot 818 pierced and from the slots 818 or openings removed or formed therefrom to the reaction dish 800 locally thickened to allow engagement with a pass component (e.g., a carrier) under reduced tension.

As in the 17A - 17F As best shown, a method of forming a component (eg, a reaction shell 700 . 800 . 900 ) comprise a series of thickening steps. Such a method may be used to form a "top" material portion, such as by extrusion of a bore or holes, or around the periphery of a blank while still in its "green state". The 17A - 17F For example, show a cross section of in 16B shown first reaction shell 700 , The process begins by cold forming a flat boron steel blank into a predetermined tubular, blank or unfinished form 1000 how best 17A shown. Next punching the unfinished form 1000 with a punching tool 1001 to make holes 1002 ( 17B) , The stamping is done while the part 1000 still in the "green state" to produce "upwardly trained" material. As in 17C As shown, the method proceeds with a heat treatment of the predetermined tube shape 1000 (for example, in an inert environment). The next steps of the method are transmitting the predetermined tube shape 1000 to the quenching and calibration tool 1004 and compressing the predetermined tubular shape (that is, the "upwardly-formed" material) using the tool 1004 for forming the desired geometry and thickness while the predetermined tubular shape 1000 stays hot ( 17D) , The desired geometry and thickness can be thickened areas 1006 include. In particular, the geometry and thickness are controlled by factors such as, but not limited to, tool stops and press strokes. Next, hold the predetermined tube shape 1000 under compression until it is cooled, with the tool in position, as in 17E shown. The finished part 1008 is in 17F best shown and has thickened areas 1006 on.

As in the 18A - 18E As best shown, a method of forming a component (e.g., reaction shell 700 . 800 . 900 ) a series of thermoforming steps in which the punching tool 1101 is removed. Such a method can be used, for example, when the ultra-high strength steel is to be formed without shearing to the selected geometry (for example, forming a snap ring groove or bent tab).

The 18A - 18E For example, show a cross section of in 16B shown first reaction shell 700 , The process begins with heating a blank or an unfinished mold 1100 (For example, a predetermined tubular shape) in a mold 1104 ( 18A) , In one aspect of the disclosure, the blank becomes 1100 heated to about 900 ° C (degrees Celsius). Next punching the unfinished form 1100 by partially pressing the blank 1100 with the punching tool 1101 ( 18B) , The punching takes place while the unfinished form 1100 is hot. As in 18C As shown, the procedure continues with removal of the punching tools 1101 and holding the tool in contact with the blank 1100 continued. The punching tools 1101 Can be removed or withdrawn before the material 1100 is quenched and the martensitic structure is formed. The next steps of the procedure are quenching the unfinished form 1100 with removed punching tools 1101 while the unfinished part with the tool 1104 is in contact until it cools down ( 18D) , The finished part 1108 is in 18E best shown.

As in the 19A - 19E As best shown, a method of forming a component (e.g., reaction shell 700 . 800 . 900 ) a series of thermoforming steps in which the punching tool 1201 is held in position. Such a method may be used, for example, when the ultra-high strength steel is to be formed without shearing to the selected geometry (for example, forming a snap ring groove). The 19A - 19E For example, show a cross section of in 16B shown first reaction shell 700 , The process begins with heating a blank 1200 or an unfinished shape (for example, a predetermined tube shape) in a mold 1204 ( 19A) , In one aspect of the disclosure, the blank becomes 1200 heated to about 900 ° C. Next punching the unfinished form 1200 by partial pressing with the punching tool 1201 ( 19B) , The punching takes place while the unfinished form 1200 is hot. As in 19C shown, the method moves with holding the punching tools 1201 continued. The process continues with quenching the unfinished mold 1200 and keeping the tool in contact 1204 with the blank 1200 while the punching tools 1201 with the unfinished part 1200 are in contact, away. By keeping the punching tools in place 1201 they can support quenching as long as the geometry allows, and there is no pinning. The procedure concludes with the removal of the punching tools 1201 after cooling ( 19D) , The finished part 1208 is in 19E best shown.

As in the 20A - 20E As best shown, a method of forming a component (e.g., reaction shell 700 . 800 . 900 ) comprise a series of hot punching steps. Such a method can be used, for example, when the ultra-high-strength steel is to be sheared and the punching tools 1301 then be withdrawn before the material 1300 is quenched and the martensitic structure is formed. The 20A - 20E For example, show a cross section of in 16B shown first reaction shell 700 , The process begins with heating a blank 1300 or an unfinished shape (for example, a predetermined tube shape) in a mold 1304 , In one aspect of the disclosure, the blank becomes 1300 heated to about 900 ° C. Next, extend the punching tools 1301 for shearing the blank 1300 or the unfinished form ( 20B) , The punching takes place while the unfinished form 1300 is hot. As in 20C As shown, the procedure continues with removal of the punching tools 1301 continued. The process continues with quenching the unfinished mold with removed punching tools 1301 and holding the tool in contact 1304 with the blank 1300 as best in 20D shown. The finished part 1308 is in 20E best shown.

As in the 21A - 21E As best shown, a method of forming a component (e.g., reaction shell 700 . 800 . 900 ) comprise a series of thermoforming steps in which the punching tool 1401 for forming a feature, such as a tab surface 1410 , is held in position. Such a method can be used, for example, when the ultra-high strength steel to be bent to the selected geometry (for example, forming a tabbed surface 1410 ). The 21A - 21E For example, show a cross section of in 16B shown first reaction shell. The process begins with heating a blank 1400 or an unfinished shape (for example, a predetermined tube shape) in a mold 1404 ( 21A) , In one aspect of the disclosure, the blank becomes 1400 heated to about 900 ° C. Next, make the tab area 1410 to the unfinished form by turning an edge into the surface 1410 by a punching tool 1401 is pushed through ( 21B) , The making is done while the unfinished form 1400 is hot. As in 21C As shown, the method moves to completion of forming the tab surface 1410 by completely passing the punching tool 1401 and holding in position of the stamping tool 1401 continued. The process continues with quenching the unfinished mold 1400 and holding the tool 1404 in contact with the blank 1400 while the punching tools 1401 with the unfinished part 1400 are in contact ( 21D) , continued. By keeping the punching tools in place 1401 they can support quenching as long as geometry allows, and there is no pinning. The procedure concludes with the removal of the punching tools 1401 after cooling. The finished part 1408 is in 21E best shown.

As in the 22A - 22E As best shown, a method of forming a component (e.g., reaction shell 700 . 800 . 900 ) comprise a series of thermoforming steps in which the punching tool 1501 for forming a feature, such as a tab surface 1510 , Will get removed. Such a method may be used, for example, when the ultra-high strength steel is to be bent to the selected geometry (e.g., forming a tab area) 1510 ). The 22A - 22E For example, show a cross section of in 16B shown first reaction shell 700 , The process begins with heating a blank or an unfinished mold 1500 (For example, a predetermined tubular shape) in a mold 1504 ( 22A) , In one aspect of the disclosure, the blank becomes 1500 heated to about 900 ° C. Next, make the tab area 1510 to the unfinished form 1500 by turning an edge into the surface 1510 by a punching tool 1501 is pushed through ( 22B) , The making is done while the unfinished form 1500 is hot. As in 22C As shown, the method moves to completion of forming the tab surface 1510 by completely passing the punching tool 1501 continued. The next steps in the process are removing the punching tool 1501 and quenching the unfinished form 1500 and holding the tool 1504 in contact with the blank 1500 ( 22D) , The finished part 1508 is in 22E best shown.

As in the 23A - 23E As best shown, a method of forming a component (e.g., reaction shell 700 . 800 . 900 ) comprise a series of thermoforming steps in which the punching tool 1601 for forming a feature, such as a tab hole 1612 , is held in position. Such a method may be used, for example, when the ultra-high strength steel is to be bent to the selected geometry (for example, forming a tab hole 1612 ). The 23A - 23E For example, show a cross section of in 16B shown first reaction shell 700 , The process begins with heating a blank 1600 or an unfinished shape (for example, a predetermined tube shape) in a mold 1604 ( 23A) , In one aspect of the disclosure, the blank becomes 1600 heated to about 900 ° C. Next, make a tab hole 1612 to the unfinished form by turning an edge into a flap surface 1610 by a punching tool 1601 is pushed through and one side of the unfinished part 1600 shears off ( 23B) , The making is done while the unfinished form 1600 is hot. As in 23C As shown, the method moves to completion of forming the tab hole 1612 by completely passing the punching tool 1601 and holding in position of the stamping tool 1601 continued. The process continues with quenching the unfinished mold 1600 and holding the tool 1604 in contact with the blank 1600 while the punching tools 1601 with the unfinished part 1600 are in contact ( 23D) , continued. By keeping the punching tools in place 1601 they can support quenching as long as geometry allows, and there is no pinning. The procedure concludes with the removal of the punching tools 1601 after cooling. The finished part 1608 is in 23E best shown.

As in the 24A - 24E As best shown, a method of forming a component (e.g., reaction shell 700 . 800 . 900 ) comprise a series of thermoforming steps in which the punching tool 1701 for forming a feature, such as a tab hole 1712 , Will get removed. Such a method may be used, for example, when the ultra-high strength steel is to be bent to the selected geometry (for example, forming a tab hole 1712 ). The 24A - 24E For example, show a cross section of in 16B shown first reaction shell 700 , The process begins with heating a blank 1700 or an unfinished shape (for example, a predetermined tube shape) in a mold 1704 ( 24A) , In one aspect of the disclosure, the blank becomes 1700 heated to about 900 ° C. Next, make a tab hole 1712 to the unfinished form by turning an edge into the flap surface 1710 by a punching tool 1701 is pushed through and one side of the unfinished part 1700 shears off ( 24B) , The making is done while the unfinished form 1700 is hot. As in 24C As shown, the method moves to completion of forming the tab hole 1712 by completely passing the punching tool 1701 continued. The next steps in the process are removing the punching tool 1701 and quenching the unfinished form 1700 and holding the tool 1704 in contact with the blank 1700 ( 24D) , The finished part 1708 is in 24E best shown.

It should be obvious that in the 21A - 24E shown views only a cross section of a half of a cylindrical part (for example, the reaction tray 700 . 800 . 900 ) demonstrate. It should be understood that the illustrated process steps, punching tool and tool geometry are generally shown as sharp edges, but may have a rounding instead of a sharp edge. It will be understood that while the steps may be performed with a tubular portion, the method may be practiced for other portions of components such as those described herein or the other general forms including sheets.

An example of a thermoforming application to a tab hole 1812 , as disclosed herein, is characterized by the 25A - 25D shown. In particular shows 25A a punching tool 1801 , the for forming a tab hole 1812 with a rounding off 1814 ( 25B) instead of punching with a sharp edge. Such a rounding off 1814 may be useful to act as a fulcrum, for example, for a clutch operating lever 1816 ( 25B) , 25C represents a clutch drum assembly 1818 in which such a tab hole 1812 can be used. 25D shows a cross section of in 25C shown clutch drum assembly 1818 , In particular, the clutch housing assembly 1818 clutch plates 1820 , the clutch lever 1816 and a coupling ball ramp 1822 contain. The hot-forming tab hole 1812 For example, which may be advantageously formed by methods described herein may be provided by the clutch operating lever 1816 be engaged. The longer the drum, the harder it is to pull off part of the set ID mandrel. For example, the removal of the part may require a motion tool.

In each embodiment of the present disclosure, the components may be formed from 22MnB5 steel, but it is understood that the amount of boron ( B5 - B50 ) can be selected depending on the desired type of component or strength. In addition, the amount of other materials comprising the ultra-high strength steel, such as carbon, may result in a change in martensitic percentage and hardness after quenching. During the heat treatment, the heating temperature may be about 850-950 ° C. In particular, the target heating temperature for 22MnB5 steel may be 900 ° C; However, the heating temperature can be increased with increasing amount of boron. As described above, the heat treatment may be partially or completely localized. The heating process may be by induction or other techniques. Preferably, the heating takes place in an inert atmosphere. If the strength is to be located in a particular area of a component, the heat treatment can be localized to that area. In other cases, a localized heat treatment may be used for portions of a component that have a thicker cross-section.

During the quenching step that may be used in forming each embodiment of the present disclosure, the quench press defines the final shape of the part. The demolding temperature may be between about 150 - 250 ° C at a preferred target temperature of 200 ° C. The components generally remain in the quench press for about 6 to 20 seconds, depending on the cross-sectional thickness and desired strength.

In general, materials having a tenacity of about 1000 MPa will break or rebound during cold forming, and therefore the methods described in the present disclosure are advantageous when forming with such high strength materials. Moreover, due to a reduction in the cross-section, the geometry of the components produced by heat-assisted calibration (HAC) methods disclosed herein may be more complex (e.g., ribs). Consequently, the production of some components (for example, the planetary carrier described in the above fifth embodiment), which may not be possible using cold forming, is enabled by HAC processes described herein.

Current thermoforming of boron steel may also focus on structural components having shapes and features designed to mate and interact with a vehicle structure. These features are formed with components that are mostly stationary during the thermoforming process step. They are also larger features that generally have larger tolerances. However, with a transmission or driveline component, the tolerances are much narrower (in a range of 5 to 10 times), and their accuracy determines their behavior when interacting with passport components. Torque-transmitting features, such as splines, are particularly critical as torque-transmitting interfaces and are tightly controlled.

Conventional techniques for thermoforming splines, such as pulling over a mandrel, are not effective in molding complete spline profiles, particularly with longer spline teeth. They also result in excessive material thickness as a more uniform tooth portion is created. In addition, spline tip and root radii are large, which reduces the effective radial spline length (interface).

Another disadvantage of using a fixed tooling process is that the longer the splined component, the harder it is to pull the component away from a specified ID mandrel. Extraction becomes difficult because of complex part geometry, which makes it difficult to extract components after thermoforming and cooling the part. This also leads to excessive tool wear and shortened tool life.

According to the present disclosure, one solution is to use one Tool movement from the part's AD, the part's ID or both directions to create a detailed spline geometry. This also allows the component to be formed with a large effective spline length and changed part cross-section to minimize weight. This also minimizes the tooth tip and root radii and results in a larger effective radial tooth area which allows the component to be designed with a shorter total tooth height since compensation for large radii is not required.

The process of the present disclosure is described in various embodiments thereof with process diagrams, and images are incorporated in the 26 - 35 provided. In general, the solution focuses on the movement of tool segments to form spline teeth and other complex geometries within the part in conjunction with HAC processing. All splines and features are formed simultaneously using segments positioned 360 degrees around the part. Components can be formed by swaging round blanks, rectangular blanks, or pre-machined forgings. Blanks, flat or with / without other feature (s), can be used before the HAC. The tooth geometry is specific when made by a cam die. Cam die technology allows flexibility in spline angle design. Wedge tooth lengths of 30-40 mm are typical, and longer splines with sufficient press force and tool length can be produced. Involute spline geometry is also possible due to active tool movement, which results in virtually no drag on the part.

In general, the images taken in the drawings include tool movement with the following options: 1) AD formation by segmented cam die, rollers, etc., fixed mandrel; 2) ID formation by segmented cam die or other method - fixed tool AD; or 3) ID + AD formation provides the greatest flexibility by providing fully active tooling.

The above may also include the option of AD formation of the splines using a roll forming tool. The teeth would be formed by the roller and allowed to cool without roller contact. When parts are formed with the roll forming tool, there is an impression on the tip of the spline tooth along the axial length. In the roll forming option, there is also the possibility of forming the spline by roll forming while the component is supported by an expanding mandrel and inserted into a secondary part of the tool which collapses around the component and then performs quenching.

Cooling / quenching can both be accomplished by using several methods. For example, the process tool can be done using cooling channels or in-mold using direct quenching with a fluid surge in the tool. The method may include ejecting the part after thermoforming and quenching it in a fluid bath. The part may also be formed with all features prior to heating to an austenitizing temperature, whereafter it is heated and cooled in a fluid bath.

Based on the cooling rate along with the plastic deformation primarily in the splines or other features formed during the hot stamping process step, metallurgical differences may be noted. It can be a differentiation of parts that are simply heated and quenched without forming - be it in the tool or in a fluid medium - are allowed.

Partial features with tight tolerances, such as splines, are formed using the HAC process. Using the HAC process results in extremely strong parts that work very well with passport components. Good part definition allows optimization for weight reduction, resulting in reduced rotational inertia and component mass - reducing overall transmission weight and increasing efficiency.

Now on 26 Referring to FIG. 1, a spline forming process for torque transmitting components made from ultra high strength steel (such as boron steel) is disclosed and generally indicated by the reference numeral 2000 characterized. It will be obvious to those skilled in the art that according to this process 2000 formed splines may be formed on a plurality of torque transmitting components of any kind previously with reference to the 1 to 25 be disclosed component. In any case, those encompass or surround according to the process 2000 Wedge teeth formed in whole or in part, a tubular segment of the component, wherein such a segment may be configured to be subsequently engaged via a spline with another component having either outer or inner mating spline teeth. It is intended that the spline formation process 2000 an alternative to those with reference to the 4 - 7 disclosed spline forming method with the purpose of forming the spline teeth now before the quenching process.

The spline formation process 2000 comes with a first step 2002 the provision of a flat blank made of ultra-high-strength steel. A second step 2004 The process includes forming a cup-shaped preform without splines. In a third step 2006 For example, the parison is heated to a predetermined temperature which, in this non-limiting example, is in a range of 900-950 ° C. Although an inert atmosphere is preferred for this preform heating step, those skilled in the art will recognize that the present invention is not limited thereto. According to a fourth step 2008 In the spline forming process, the heated cup preform is installed on a "fixed" mandrel of a wedge die set or die set. After that, in a fifth step 2010 activating an AD tool segment of the wedge forming tool set to engage the cup preform and deform the preform over a spline feature associated with an outer surface of the fixed mandrel. Subsequently, the splined component (while retained in the closed die set) is quenched to a predetermined temperature, which in this non-limiting example is about 200 ° C, as by a sixth step 2012 of the process. In a seventh step 2014 For example, the AD die segment of the die set is retracted / released to allow subsequent ejection / removal of the splined component from the fixed mandrel, as by the eighth step 2016 displayed. The cup-shaped component made in accordance with this HAC and spline forming process includes a continuous spline periphery configured to mate with another component.

step 2010 of the spline formation / HAC process 2000 from 26 includes an "alternatives" block 2011, an example of which is shown in FIG 27 will be shown. The AD education alternative uses a number of "segmented" AD tools 2030 used to form a 360 ° uniform spline formation of a cup-shaped preformed hub 2032 are arranged. The cup-shaped preformed hub 2032 surrounds a fixed mandrel in the representation 2034 , the splines formed thereon 2036 which alternately on in each of the AD tool segments 2030 trained spline features 2038 are aligned. In 27A is the heated cup-shaped preformed hub 2032 on the stipulated spine 2034 where each of the AD tool segments 2030 concerning the spine 2034 is in a retracted position. 27B (via the arrow 2040 ) is a radially inwardly directed pressing force passing through the AD tool segments 2030 is applied to the cup-shaped preform 2032 with respect to the spline characteristics 2036 . 2038 deform radially in order to form the spline teeth in their final contour. 27C (via the arrow 2042 ) a movement of the AD tool segment 2030 in its retracted position with respect to the spine 2034 following the quenching process in the tool. The cup-shaped preform 2032 includes in the illustration a continuous tubular rim segment, in this non-limiting example, internal spline teeth 2044 and external spline teeth 2046 Are defined. 27D FIG. 10 illustrates removal / ejection of the completed splined component from the mandrel. FIG.

Now on 28 Referring now to Figure 1, a modified version of a spline formation process is now shown 2000 from 26 by the reference number 3000 characterized. The steps of the spline forming HAC process 3000 that of process 2000 are denoted by common reference numbers. In general, the process is different 3000 from the process 2000 in that no fixed mandrel is used, but it becomes a segmented "spreadable" mandrel (i.e., ID tool segments) in conjunction / interaction with AD tool segments 2030 used. In a first step 2002 of the spline forming HAC process 3000 a flat blank of ultra-high strength steel (boron steel) is provided. In a second step 2004 the blank is formed into a cup-shaped preform without splines. In a third step 2006 The cup-shaped preform is heated in an inert environment to a predetermined temperature, which in this non-limiting example again between 900 and 950 ° C. Thereafter, the heated preform is placed over the expandable mandrel in its retracted position, as by the fourth step 3002 displayed. According to a fifth step 3004 of the spline forming process 3000 The ID tool segments of the mandrel are moved from their retracted position to a standby position in which they engage the inner surface of the cup-shaped preform. In a sixth step 3006 For example, the AD tool segments of the die set are spread radially inwardly, either alone or in conjunction with a radially outward spread of the ID tool segments of the mandrel, about spline teeth in the cup-shaped Form preform with the mandrel and the AD tool segment associated with spline features. A seventh step 3008 provides a quenching process in the splined component. An eighth step 3010 is the act of releasing (radially moving the ID and / or AD tool segments such that the component formed as a spline can be removed from the die set, as in step 3012 shown.

step 3004 of the spline formation / HAC process 3000 from 28 includes an "Alternatives" block in the illustration 3005 while step 3006 same process in the representation of an "Alternatives" block 3007 includes. These ID education and AD education alternatives are given in a specific but non-limiting example 29 shown. As before, the AD formation alternative uses a number of segmented AD tools 2030 , the spline features 2038 and which are arranged so that they the tubular cup-shaped preform 2032 surrounded to simultaneously form 360 ° splines. 29 however, shows that the mandrel or ID tool has a number of segmented ID tools 2034 ' used, each one a spline feature 2036 ' and which are arranged so that they from the cup-shaped preform 2032 be surrounded and spread radially at the same time. In 29A Both the AD tool segments 2030 as well as the ID tool segments 2034 ' withdrawn (concerning preform 2032 ). 29B represents an inward pressing force (arrow 2040 ) pointing to the AD tool segments 2030 is exercised, and an outward pressing force (arrow 2050 ) pointing to the ID tool segments 2034 ' This simultaneous movement of the AD and ID tool segments acts to provide the cup preform with respect to the spline features 2036 ' . 2038 deform radially for the purpose of forming spline teeth into final contour. 29C poses over the arrows 2042 and 2052 a respective radial movement of the AD tool segments 2030 and ID tool segments 2034 ' in their retracted positions following the quenching process in the tool. The cup-shaped preform 2032 now contains in the presentation continuous edge segments, the internal spline teeth 2044 and external spline teeth 2046 define. 29D illustrates the completed spline formed component following removal from the tool / die set.

30 provides splines formed using a conventional method called "ironing" 4000 To achieve an improvement over the prior art, AD tool segments associated with the AD formation of the present disclosure employ a segmented cam die or a segmented roll die. Of course, the ID tool segments associated with ID spline formation of the present disclosure may also utilize a similar segmented cam die or roll forming tool. An example of an AD tooling segment embodying the present disclosure produced a spline shape 4002 is in 31 shown. This spline shape 4002 compared to the "ironed" spline shape 4000 a non-uniform wall thickness and larger corner radii.

32 represents one (the process of 26 and 27 using) cam die spline formation process with multiple AD cam die segments. The preform 4004 is heated and segmented AD cam die segments 4006 (one shown) move within a cam slide tool set 4008 to an outer spline 4010 in the finished component 4012 to create. As an alternative to this 33 one (the process of 26 and 27 using) a roll forming tool spline forming process with a plurality of AD roll forming tool segments. The preform 4004 is heated, and roll forming tool segments 4020 (one shown) move axially and radially with respect to the preform 4004 to an outer spline 4022 in the finished component 4024 to create. Another view of the roll forming tool spline molding processing is described in FIG 34 shown.

The 35A - 35C illustrate an HAC roll forming tooling process. 35A defines that a segmented, radially movable internal tool 5000 , a fixed roll cassette 5002 and a segmented, radially movable outer tool 5004 cooperate to carry out this process. 35B defines a set of the toolkit of 35A associated process steps 1 - 5 , In step 5006 the hot blank is loaded onto the "inner tool". In step 5008 the "inner tool" is spread open. In step 5010 the hot blank is pushed through the "roll cassette" into the "outer tool". In step 5012 Fold the "outside tool" and the quenching piece together. In step 5014 The tools for extracting the quenched component are spread open and collapsed. Finally, poses 35C different positions 1 - 3 that is the process of 35B assigned. This configuration is to allow the formation of features by rolling similar to cold rolling while the blank is hot. Add the tool 5004 to the Inkontakhalten immediately after the rolling process in connection with the tool 5000 to keep in contact while cooling and to maintain the geometry. Without the tool 5004 in position after the rolling process, the blank would try to spring back to its original shape after the rolls. The movable tool allows easy release of the finished part after cooling.

LIST OF REFERENCE NUMBERS

10

clutch housing

12, 502

radial ring part

14, 504, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700

Band / blank

15

cylindrical drum part

16, 512, 586, 822, 922

Spline teeth

100, 200, 300, 400, 2002, 5006

first step

102, 202, 302, 402, 2004, 5008

second step

104, 204, 304, 2006, 5010

Third step

2008, 3002, 5012

fourth step

2010, 3004, 5014

fifth step

2012, 3006

sixth step

2014, 3008

seventh step

2016, 3010

eighth step

3012

ninth step

500

clutch

506

tubular neck

508

drive gear

510

triangular openings

520

CVT follower

522

centrally located opening

540

CVT-cylinder

542

first end

544

second end

546, 708, 808

shoulder

548

opening

560

planet carrier

562

first part of the planet carrier

564

second part of the planet carrier

566

breakthroughs

568

leg

580, 700, 800, 900

reaction tray

582, 710, 810

cylindrical first part with a first diameter

584, 712, 812

cylindrical second part with a second diameter

588

drilling

702, 802, 902

body

704, 804, 904

proximal end

706, 806, 906, 908

distal end

714, 814

first flange

816

second flange

818

slots

719, 819

first holes

820

elongated shoulder bores

724, 824

triangular holes

826

Speed sensor holes

928

Splined bores

930

snap ring

1001, 1101, 1201, 1301, 1401, 1501, 1601, 1701, 1801

punching tool

1002

holes

1004, 1104, 1204, 1304, 1404, 1504, 1604, 1704

Quenching and calibration tool / mold

1006

thickened areas

1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700

unfinished form

1008, 1108, 1208, 1308, 1408, 1508, 1608, 1708

finished part

1410, 1510, 1610, 1710

tab face

1612, 1712, 1812

Lasch hole

1814

rounding off

1816

Clutch operating lever

1818

Clutch drum arrangement

1820

clutch plates

1822

Clutch ball ramp

2000.3000,

Spline forming process

2011, 3005, 3007

"Alternatives" block, ID / AD education alternative

2030

AD-tool segments

2032, 4004

cup-shaped preformed hub / preform

2034

mandrel

2034 '

ID tool segments

2036, 2036 ', 2038

Spline features

2040

radially inward pressing force

2042

Movement in retracted position

2044

internal spline teeth

2046

outer spline teeth

2050

outward pressing force

4000.4002

Spline shape

4006

AD Nockengesenkwerkzeugsegmente

4008

Nockengleitwerkzeugsatz

4010, 4022

outer spline

4012, 4024

finished component

5000

radially movable internal tool

5002

fixed roll cassette

5004

segmented, radially movable outer tool

Claims (15)

A method of forming a spline (4010, 4022) in a component using ultra-high strength steel, comprising the steps of: Providing a flat blank (14) of ultra-high strength steel (2002) forming the blank into an unfinished shape (1300, 1400, 1500, 1600, 1700) of a component (2004) Heating the unfinished mold (1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700) of the component (2006); and Forming a finished mold (1008, 1108, 1208, 1308, 1408, 1508, 1608, 1708) of the spline-containing component using a quenching die having a radially movable segmented tool (5000, 5004). Method according to Claim 1 further comprising: providing an inert atmosphere; and heating the unfinished mold (1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700) of the component in the inert atmosphere. Method according to Claim 2 wherein the step of heating the incomplete mold (1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700) of the component in the inert atmosphere further comprises heating the unfinished mold (1000, 1100, 1200, 1300, 1400, 1500 , 1600, 1700) of the component in the inert atmosphere at a temperature between 850 ° C and 950 ° C. Method according to Claim 1 wherein the step of heating the unfinished mold (1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700) of the component further comprises heating the unfinished mold (1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700 ) of the component is defined at a temperature between 850 ° C and 950 ° C. Method according to Claim 1 wherein the step of forming the flat blank into an unfinished shape (1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700) of a component further defines as forming the flat blank into a cup-shaped preform (2032, 4004) without splines is. Method according to Claim 5 , further comprising: installing the cup-shaped preform (2032, 4004) on a predetermined mandrel, wherein the fixed mandrel (2034) includes a spline. Method according to Claim 6 wherein the step of installing the cup-shaped preform (2032, 4004) on a predetermined mandrel further comprises aligning the spline of the fixed mandrel (2034) alternately with a spline of the radially movable segmented tool. Method according to Claim 6 wherein the step of installing the cup-shaped preform (2032, 4004) on a predetermined mandrel (2034) further comprises aligning the radially movable segmented tool in a retracted position with respect to the fixed mandrel (2034). Method according to Claim 1 wherein the step of forming a final shape of the component using a quenching die is further defined as forming a final shape of the component with spline using a quenching die upon cooling the component to a temperature between 150 ° C and 250 ° C. Method according to Claim 1 wherein the step of forming a final shape of the component using a quenching die is further defined as forming a final shape of the component using a quenching die in forming a plurality of spline teeth in the component using the quenching die. Method according to Claim 1 wherein the step of forming a final shape of the component using a quenching die is further defined as arranging a series of radially movable segmented tools to completely surround and enclose the component for simultaneously forming all of the splines. Method according to Claim 1 wherein the step of forming a final shape of the component using a quenching die further comprises forming the unfinished shape into a cylindrical shape having a radial ring portion and a cylindrical barrel portion and forming a plurality of spline teeth in the cylindrical barrel portion of the coupling housing using the segmented die portions of the quenching die as formed the final shape is defined Method according to Claim 1 further comprising: releasing the radially movable segmented tool; and removing the component. Method according to Claim 1 , where the flat blank is made of ultra high strength steel of the ultra high strength 22MnB5 steel type. Method according to Claim 1 wherein the final shape comprises a cylindrical body and / or a cup-shaped body.

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