JP2010007146A - Quenching apparatus, method for quenching material to be treated and placing stand for use in them - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a quenching apparatus which suppresses an increase in variation in amount of deformation or strain occurring in material to be treated. <P>SOLUTION: The quenching apparatus 1 is provided with an oil vessel 5 stored with quenching oil Y, a placing stand 8 for placing the materials W to be treated on the upper surface thereof and a conveying device 6 for dipping the materials W to be treated into the quenching oil Y. The quenching apparatus 1 is further provided with delivering hole 7c for delivering the quenching oil Y upward at the bottom part of the oil vessel 5a and a circulating device 7 for circulating the quenching oil Y. The placing stand 8 is provided with a flow straightening plate 11 for introducing the flow of the quenching oil Y formed by the circulating device 7 to above a fork 6a. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a quenching apparatus for quenching a workpiece such as a machine part, a quenching method for the workpiece, and a mounting table used for these.

Conventionally, a quenching apparatus for quenching workpieces such as steel machine parts is a cooling tank in which a coolant such as quenching oil for rapidly cooling the workpieces heated to the quenching temperature is stored. have. The quenching apparatus places a heated object to be processed on a fork of an elevating apparatus provided in the quenching apparatus via a mounting table, and immerses the whole fork in a cooling liquid to quench (quenching). I do.
The cooling tank of the quenching apparatus has a cooling liquid discharge port at the bottom of the cooling tank, and circulates the cooling liquid in the cooling tank by discharging the cooling liquid upward from the discharge port. Is arranged. The circulation device guides the flow of the coolant from the discharge port to the workpiece immersed in the coolant, and quenching is performed while ensuring a predetermined cooling rate (see, for example, Patent Document 1).

JP-A-2005-350756

In the conventional quenching apparatus, the fork is immersed in the coolant with the fork in a state where the workpiece is placed on the fork, so that the flow of the coolant from the bottom side of the cooling tank is blocked by the fork, In some cases, the flow of the cooling liquid cannot be evenly guided with respect to the workpiece.
For example, when heat treating an object to be processed arranged three-dimensionally by stacking a large number of mechanical parts such as annular members in the basket, the flow of the cooling liquid cannot be uniformly guided to the object to be processed. In addition, the cooling rate of the mechanical parts such as the annular members in the basket becomes non-uniform, and the variation in the amount of deformation and distortion generated in the mechanical parts such as the annular members becomes large.
When the variation in the amount of deformation and strain that occurs in each annular member and other mechanical parts becomes large, the deformation and distortion of each annular member and other mechanical parts can be removed by turning and polishing in the processing step after heat treatment, and sizing, etc. When removing deformation and distortion by plastic working, the working time may take a long time, leading to a decrease in production efficiency.

Therefore, by adjusting the circulation conditions such as the flow rate and flow rate of the cooling liquid, setting is made so that the flow of the cooling liquid is guided to a certain extent.
For example, when a predetermined number of mechanical parts such as annular members having a predetermined size are arranged and a circulation condition such as a flow rate or a flow rate of a coolant is set as an appropriate value for a certain object to be processed, Variations in the amount of deformation and distortion occurring in machine parts such as the annular members of the processed material are suppressed.

  However, in the case of heat-treating other workpieces having different sizes, numbers and arrangements of mechanical parts such as annular members, it is necessary to change the circulation conditions such as the flow rate and flow rate of the coolant. In addition, it takes time and readjustment of the temperature of the coolant stored in large quantities. As described above, since suitable circulation conditions vary depending on the size and number of objects to be processed, work time is required to appropriately adjust the circulation conditions according to the objects to be processed, and production efficiency is reduced. .

  In addition, even when the circulation condition is suitable for a certain object to be processed, when other different objects to be processed are heat-treated, similarly to the above, variations in the amount of deformation and distortion occurring in the machine parts such as the respective annular members may occur. In this case as well, the production efficiency is reduced due to an increase in the processing time of the subsequent processing steps.

  The present invention has been made in view of such circumstances, and it is possible to increase the variation in the amount of deformation or distortion that occurs in the workpiece (machine parts such as each annular member) without reducing production efficiency. It aims at providing the quenching apparatus etc. which can be suppressed.

  The present inventors use a quenching apparatus having a cooling tank in which a coolant for quenching is stored, and quench (rapidly cool) a workpiece formed by three-dimensionally stacking a number of mechanical parts such as annular members. In carrying out the research, intensive research was conducted to suppress the variation in the quality of the workpiece. In the process, various experiments were conducted focusing on the fact that the flow of the cooling liquid by circulation was not evenly guided to the object to be processed. As a result, if a baffle plate is provided on the mounting table on which the object to be processed is placed, the flow of the cooling liquid becomes uneven with respect to the object to be processed without being affected by the size or number of the objects to be processed. The present invention has been completed by finding that it can be prevented from being guided.

  That is, the quenching apparatus according to the present invention is a quenching apparatus for quenching a workpiece, and a cooling tank storing a coolant for quenching the workpiece being heated to a quenching temperature; A mounting table on which the object to be processed is mounted on the upper surface and the cooling liquid can pass in the vertical direction; a support portion that supports the lower surface of the mounting table; and a passage that allows the cooling liquid to pass in the vertical direction. A lifting member for immersing the workpiece in the cooling liquid as the supporting member descends, and a discharge port for discharging the cooling liquid upward. Circulating means provided at the bottom, guiding the flow of the cooling liquid from the discharge port to the workpiece immersed in the cooling liquid through the passage of the support member and the mounting table, and then guiding the flow to the discharge port again And the mounting table passes through the passage. The part of the flow of the cooling liquid is characterized in that it has a rectifying plate for guiding the upper bearing of the support member.

  Further, the quenching apparatus according to the present invention is a quenching apparatus for quenching an object to be processed arranged three-dimensionally in a state where a large number of machine parts such as annular members are stacked, and is heated to a quenching temperature. A cooling tank in which a cooling liquid for rapidly cooling the object to be processed is stored, a mounting table on which the processing object is mounted and the cooling liquid can pass vertically, and a lower surface of the mounting table Elevating means for immersing the object to be treated in the cooling liquid as the supporting member descends. A discharge port for discharging the cooling liquid upward is provided at the bottom of the cooling tank, and the flow of the cooling liquid from the discharge port is immersed in the cooling liquid through the passage of the support member and the mounting table. After being guided to the treated object, the discharge port again Circulation means and has a mounting table for guiding is characterized by having a rectifying plate for guiding a portion of the coolant flow passing through the passage above the bearing of the support member.

According to the quenching apparatus configured as described above, the flow of the cooling liquid can be rectified so that the flow of the cooling liquid by the circulation means is guided to the upper side of the support member by the rectifying plate of the mounting table. It is possible to suppress being guided unevenly with respect to the workpiece. As a result, it can suppress that the cooling rate of machine parts, such as each annular member, becomes non-uniform | heterogenous, and can suppress that dispersion | variation arises in the quality.
In addition, since the flow of the cooling liquid is rectified by the baffle plate of the mounting table, the flow of the cooling liquid is unevenly distributed with respect to the object to be processed without being affected by the size or number of mechanical parts such as the annular member. It can suppress being guided. For this reason, regardless of the size, number, and arrangement of the machine parts such as each annular member mounted on the mounting table, the variation in the amount of deformation and distortion generated in the machine parts such as each annular member after heat treatment becomes large. It is possible to suppress the decrease in production efficiency.

  Moreover, it is preferable that the said baffle plate is provided in the state inclined with respect to the perpendicular direction, and in this case, a part of the flow of the coolant can be easily guided above the support portion of the support member. . Furthermore, the angle of the current plate may be adjustable. In this case, the angle of the current plate can be easily set in the initial use of the apparatus.

Further, the present invention is a method for quenching an object to be treated, wherein the object to be treated is placed on the upper surface of the mounting table using the above-described quenching apparatus, and the object to be treated is lowered as the support member is lowered. The treated product is immersed in the cooling liquid.
According to the quenching method having the above-described configuration, as described above, it is possible to suppress an increase in variation in the amount of deformation and distortion of the workpiece after the heat treatment.

  The present invention has a support member provided with a cooling tank storing a cooling liquid for quenching and quenching the workpiece heated to the quenching temperature, and a passage through which the cooling liquid passes in the vertical direction. And elevating means for immersing the workpiece in the cooling liquid as the support member descends, and a discharge port for discharging the cooling liquid upward, at the bottom of the cooling tank, from the discharge port And a circulation means for guiding the flow of the coolant through the passage of the support member to the workpiece immersed in the coolant and then leading to the discharge port again. The lower surface of the support member is supported by the support member, the workpiece is placed on the upper surface, and the coolant can pass in the vertical direction. A part of the flow is supported by the support member. It is characterized by having a rectifying plate for guiding upward parts.

  The mounting table of the present invention is characterized by being used in the above-described quenching method.

  According to the mounting table having the above-described configuration, as described above, it is possible to suppress an increase in variation in the amount of deformation or distortion of the workpiece after the heat treatment.

  According to the quenching apparatus, the quenching method of the workpiece, and the mounting table of the present invention, deformation and distortion of the workpiece (mechanical parts such as each annular member) after the heat treatment without reducing the production efficiency. It is possible to suppress an increase in variation in the amount of.

Next, preferred embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a schematic diagram showing an example of the configuration of a quenching apparatus according to an embodiment of the present invention.
The quenching apparatus 1 is an apparatus for quenching (rapid cooling) a workpiece, and a heating furnace 2 for heating the workpiece to a quenching temperature is connected to one side surface thereof. The quenching apparatus 1 in this embodiment constitutes a so-called batch (two-chamber type) heat treatment apparatus together with a connected heating furnace 2.
The heating furnace 2 has a furnace atmosphere control device such as a heater and a fan, and heats or carburizes the workpiece W. Between the heating furnace 2 and the quenching apparatus 1, there are provided a heating furnace door 2a and a quenching apparatus door 1a that partition the two. Both doors 1a and 2a can be opened and closed by hydraulic cylinders 1b and 2b, and the inside of the heating furnace 2 is opened and closed.

  On the other side surface of the quenching apparatus 1, a carry-in entrance 1c for carrying the workpiece W into the quenching apparatus 1 and a carry-in door 1d for closing the carry-in entrance 1c so as to be opened and closed are provided. . In addition, a loading table 4 for placing the workpiece W to be loaded into the quenching apparatus 1 is installed in front of the loading port 1c. The workpiece W is placed on the upper surface of the placing table 8 having a function as a pallet and is carried into the quenching apparatus 1. Thereafter, the workpiece W is transported while being placed on the upper surface of the mounting table 8 until the heat treatment by the quenching apparatus 1 and the heating furnace 2 is completed.

FIG. 2 is a perspective view showing an aspect of the workpiece W placed on the upper surface of the mounting table 8. The workpiece W is configured to be arranged three-dimensionally in a state where annular members w1 as an example of a number of machine parts are stacked. A large number of annular members w1 are stacked such that the end surfaces of the annular members w1 positioned above and below do not contact each other.
A large number of these annular members w1 are formed in, for example, a wire mesh and stored in a basket B through which quenching oil described later can pass, and the annular members w1 at each stage are held by holding jigs arranged for each stage. By being arranged on the wire mesh, they are held in a stacked state so that the end surfaces of the upper and lower ones do not contact each other.

Returning to FIG. 1, an oil tank 5 and a transport device 6 for transporting the workpiece W inside the quenching device 1 are provided inside the quenching device 1.
The oil tank 5 stores quenching oil Y as a coolant for quenching (rapid cooling) the heated workpiece W. Above the oil tank 5, that is, the upper space in the quenching apparatus 1 is a passage through which the workpiece W carried in from the carry-in entrance 1 c passes toward the heating furnace 2.
3 is a cross-sectional view taken along line III-III in FIG. 1 and 3, the oil tank 5 is provided with a circulation device 7 for circulating the quenching oil Y. The circulation device 7 includes a motor 7 a disposed outside the oil tank 5, a circulation blade 7 b that is immersed in the quenching oil Y and driven by the motor 7 a to generate a flow of the quenching oil Y, and a bottom surface of the oil tank 5. A flow path pipe 7d that includes the discharge port 7c and guides the flow of the quenching oil Y generated by the circulation blade 7b to the discharge port. The circulation device 7 sucks the quenching oil Y from the upper end of the flow path pipe 7d. The discharge port 7c opens upward, and discharges the quenching oil Y upward as indicated by an arrow in FIG. Accordingly, the circulation device 7 circulates the quenching oil Y in the oil tank 5 while generating a flow of the quenching oil Y from the lower side to the upper side of the workpiece W.

  The transport device 6 includes a fork 6a on which the workpiece W is placed, a lifting arm 6b that supports the fork 6a, and a hydraulic cylinder 6c that lifts and lowers the lifting arm 6b. The fork 6a and the raising / lowering arm 6b are arrange | positioned inside the hardening apparatus 1, The raising position where this fork 6a is located above the hardening oil Y of the oil tank 5 in the hardening apparatus 1 by this hydraulic cylinder 6c, this raising It moves up and down between the most elevated position further above the position and the most lowered position located at the bottom of the quenching oil Y in the oil tank 5.

  The fork 6a is configured by arranging fork main bodies 6a1 which are a pair of long members in parallel to each other, and the workpiece W is placed on the top thereof. Further, the fork 6a can be expanded and contracted to the heating furnace 2 side by a driving device (not shown). Can be transported between.

When the workpiece W is carried into the quenching apparatus 1 from the carry-in entrance 1c, the carrying apparatus 6 extends the fork 6a toward the carry-in entrance 1c with the fork 6a as the raised position. Thereby, the mounting table 8 on which the workpiece W is mounted on the upper surface can be transferred from the loading table 4 and mounted on the fork 6a. The conveying device 6 supports the mounting table 8 on which the workpiece W is mounted from below by a fork 6a as a support member. Thereafter, the workpiece W is transported together with the mounting table 8.
The conveying device 6 conveys the fork 6a to the highest ascending position after the placing table 8 on which the workpiece W is placed is placed on the fork 6a, and further conveys the fork 6a into the quenching device 1 by contraction.
Thereafter, the conveying device 6 conveys the workpiece W to the heating furnace 2 by extending the fork 6a to the heating furnace 2 side.

  When the heating of the workpiece W is completed under a predetermined heat treatment condition, the conveying device 6 expands and contracts the fork 6a, whereby the workpiece W heated to the quenching temperature in the heating furnace 2 is heated in the heating furnace 2. And is conveyed again into the quenching apparatus 1. Thereafter, the transport device 6 lowers the fork 6a and the lifting arm 6b while supporting the workpiece W by the fork 6a, soaks the workpiece W together with the mounting table 8 and the fork 6a in the quenching oil Y, and quenches. Do.

  In the quenching apparatus 1 of the present embodiment, when the conveying device 6 immerses the workpiece W in the quenching oil Y of the oil tank 5 as the fork 6a and the lifting arm 6b descend, the circulation device 7 is shown in FIG. As shown, the quenching oil Y discharged from the discharge port 7c is guided to the workpiece W and the quenching oil Y is circulated.

  Here, the fork 6a of the transport device 6 is configured by arranging a pair of fork main bodies 6a1 in parallel, and the pair of fork main bodies 6a1 supports the lower surface of the mounting table 8 and the mounting table as shown in FIG. 8 Both end sides of the lower surface are covered slightly apart downward. The fork 6a is configured as a passage 6a2 through which the quenching oil Y passes between the pair of fork main bodies 6a1. That is, the fork 6a as a support member allows a pair of fork main bodies 6a1 as support parts for supporting the lower surface of the mounting table 8 and the quenching oil Y formed between the pair of fork main bodies 6a1 to pass in the vertical direction. And a passage 6a2.

The mounting table 8 is also configured so that the quenching oil Y can pass in the vertical direction.
4A is a top view of the mounting table 8, and FIG. 4B is a cross-sectional view taken along the line bb in FIG. 4A. The mounting table 8 is formed by using a heat-resistant steel plate or the like. And a current plate 11 that is orthogonally crossed and arranged inside the outer frame 9.
In the case of the figure, four rectifying plates 11 are arranged, and are arranged symmetrically with respect to the center line C parallel to the vertical direction of the outer frame 9 as shown in FIG. Among these, the pair of inner rectifying plates 11a arranged on the inner side are respectively inclined by an angle α with respect to the center line C, and the pair of outer rectifying plates 11b arranged on the outer side are respectively It is inclined with respect to the center line C by an angle β which is a value larger than the angle α. Thus, each rectification | straightening board 11 inclines in the direction away from the centerline C toward the upper surface 8a from the lower surface 8b of the mounting base 8, and is arrange | positioned so that a space | interval may open toward the upper surface 8a. Furthermore, each rectifying plate 11 is disposed such that the lower end portion thereof falls within the range between the pair of fork main bodies 6a1 when the mounting table 8 is mounted on the fork 6a.
These rectifying plates 11 are fixed by bolts 9a through which the outer frame 9 is inserted, and the inclination angles of the respective rectifying plates 11 can be appropriately adjusted by loosening the bolts 9a.
By placing the beam 10 and the current plate 11 across the outer frame 9 in the mounting table 8 having the above configuration, the workpiece W can be mounted on the upper surface 8a and the quenching oil Y can pass in the vertical direction.

Returning to FIG. 3, as described above, since the quenching oil Y can pass in the vertical direction on the mounting table 8, the flow of the quenching oil Y upward from the discharge port 7 c by the circulation device 7 is a pair of forks. The flow of the quenching oil Y passing through the passage 6a2 between the main bodies 6a1 and further passing through the passage 6a2 passes through the mounting table 8 and is guided to the workpiece W.
Since the workpiece W is formed by stacking a large number of annular members w1 as described above, the quenching oil Y guided to the workpiece W is the inner peripheral side of the annular member w1 or adjacent annular members w1. Can pass through the gap.
Thereby, the circulation device 7 guides the flow of the quenching oil Y from the discharge port 7c to the workpiece W through the passage 6a2 constituted between the pair of fork main bodies 6a1 and the mounting table 8, and then flows again. It can circulate by attracting | sucking from the upper end of the path pipe 7d.

  Further, as described above, the rectifying plate 11 of the mounting table 8 is inclined in a direction away from the center line C from the lower surface 8b of the mounting table 8 toward the upper surface 8a, and the lower end portions of the current plate 11 are paired with each other. It arrange | positions so that it may be settled in the range of the channel | path 6a2 between the fork main bodies 6a1. For this reason, even if the flow of the quenching oil Y is restricted by the fork 6a so as to go upward only from the range of the passage 6a2, the restricted flow of the quenching oil Y is placed on the mounting table 8 by the inclined rectifying plate 11. Can be rectified to the upper side of the fork body 6a1 and guided to the upper side of the fork main body 6a1.

As described above, according to the quenching apparatus 1 of the present embodiment, the flow of the quenching oil Y by the circulation device 7 is guided above the fork 6a as a support portion of the support member by the rectifying plate 11 of the mounting table 8. Therefore, the flow of the quenching oil Y can be prevented from being unevenly guided to the workpiece W regardless of the circulation condition of the quenching oil Y or the like. As a result, it can suppress that the cooling rate of each annular member w1 as an example of a machine part becomes non-uniform | heterogenous, and can suppress that dispersion | variation arises in the quality.
Further, since the flow of the quenching oil Y is rectified by the rectifying plate 11 of the mounting table 8, the quenching oil is not affected by the size or number of the annular member w1 as an example of the machine part constituting the workpiece W. It can suppress that the flow of Y is led unevenly. Therefore, it is not necessary to adjust the circulation condition of the quenching oil Y according to the size and number of the annular member w1 as an example of the machine part, and each annular member w1 as an example of the machine part to be placed on the placing table 8 is used. Regardless of the size, the number, and the arrangement, it is possible to suppress an increase in the variation in the amount of deformation or distortion generated in each annular member w1 as an example of a machine part after heat treatment.

  Moreover, in this embodiment, since the baffle plate 11 of the mounting base 8 can adjust the inclination angle with respect to the center line C, the flow of the quenching oil Y is guided upward of the fork 6 a according to the arrangement of the fork 6. Thus, the inclination angles α and β can be easily adjusted to suitable values.

In addition, the hardening apparatus of this invention is not limited to the said embodiment, The number of the baffle plates of a mounting base, arrangement | positioning, its shape, etc. can be changed suitably.
Moreover, according to the said embodiment, although the case where the support part of the supporting member of the raising / lowering means was made into the fork 6a was illustrated, the said support part may be what kind of shape, as long as the mounting base 8 is mounted. Also in this case, the baffle plate 11 of the mounting table 8 is formed so that the lower end portion introduces the quenching oil Y from a position avoiding the support portion, and the upper end portion guides the quenching oil Y above the support portion. It is preferable. More specifically, the rectifying plate 11 of the mounting table 8 is inclined so that the lower end is disposed at a position avoiding the support and the upper end is disposed above the support. Is preferred.

Next, the results of a verification test performed by the present inventors for evaluating the variation in the quality of an object to be processed (an annular member as an example of a number of machine parts) by the quenching apparatus of the present invention will be described.
As an example product of the present invention, a quenching apparatus using the above-described mounting table 8 is prepared, and as a comparative example product, a current plate is provided on the outer frame similar to the outer frame 9 of the mounting table 8 of the example product. Instead, a quenching apparatus using a mounting table in which three beams parallel to the vertical direction are arranged transversely was prepared.
As a test method, a simulation on the flow state of the quenching oil Y in the oil tank was performed by CAE or the like, and the flow states of both quenching oils Y were compared. Furthermore, both were actually quenched and the effect of the quenching oil circulation conditions on the quenching quality was verified.

FIG. 5 is a diagram showing the results of simulation using the flow state of the quenching oil in the oil tank as a flow velocity distribution, where (a) shows the results of the example product and (b) shows the results of the comparative product. In the figure, a region R1 indicates a flow velocity of less than 0.1 m / second, a region R2 indicates a flow velocity of 0.1 to 0.2 m / second, and a region R3 indicates a flow velocity of 0.2 m / second or more. In this simulation, the flow rate when only the liquid quenching oil Y flows in the state where the same circulation condition is set and the workpiece is not placed is analyzed.
In FIG. 5, in the comparative example product, the region (region R2 + region R3) having a flow velocity of 0.1 m / second or more appears only near the center of the upper surface of the mounting table, whereas in the example product, A region having a flow velocity of 0.1 m / second or more also appears above the fork 6a (fork main body 6a1). For this reason, the area | region with a flow velocity of 0.1 m / sec or more appears in the wide area | region of the upper surface side of a mounting base. From this result, it can be seen that according to the example product, the flow of the quenching oil Y is more uniformly rectified on the upper surface side of the mounting table.

Next, the result of verifying the influence of the circulation condition of the quenching oil Y on the quenching quality of the workpiece (an annular member as an example of many machine parts) when actually quenched will be described.
As the workpiece W that was actually quenched, a product in which a large number of annular members w1 were three-dimensionally stacked in a predetermined basket B as shown in FIG. Specifically, bearing outer rings (outer diameter 72 mm, axial width 17 mm) equivalent to JIS6207 as the annular member w1 are stacked in basket B in 10 stages, each in vertical and horizontal directions and in the height direction of 400 mm. The outer ring was arranged so that And it hardened by hold | maintaining the said to-be-processed object at 830 degreeC, and then immersing in the hardening oil Y set to the oil temperature of 80 degreeC. At this time, as the circulation conditions of the quenching oil Y, two levels of different conditions were set by adjusting the motor rotation speed of the circulation device. Specifically, for each of the example product and the comparative product, quenching (rapid cooling) is performed under different conditions for the amount of quenching oil Y discharged by setting the motor rotation speed of the circulation device to two levels of 30 Hz and 70 Hz. The to-be-processed object (many outer rings) which performed quenching was obtained.

  The quenching quality of the outer ring was evaluated by measuring the elliptic strain before and after quenching of the outer ring, calculating the amount of change in the elliptical strain for each of a large number of outer rings, and obtaining the average value and numerical range. The elliptic distortion is a difference between the maximum outer diameter dimension and the minimum outer diameter dimension of the outer ring, and the variation amount of the elliptic distortion is a difference in elliptic distortion before and after quenching. That is, if the variation in the amount of change in elliptical strain is small, it is evaluated that there is no variation in the cooling rate at the time of quenching in each outer ring, and the flow of the quenching oil Y at the time of cooling is evenly guided to the workpiece W. can do.

FIG. 6 is a graph showing the relationship between the amount of change in the elliptical distortion of the outer ring and the circulation condition of the quenching oil Y. In FIG. 6, the vertical axis indicates the amount of change in elliptical distortion, the horizontal axis indicates the motor rotation speed of the circulation device, the black circle indicates the average value of the example product, and the white circle indicates the comparison product. Average values are shown. In addition, horizontal lines arranged above and below corresponding to the circles indicate the maximum value and the minimum value, respectively.
In FIG. 6, when the example product and the comparative product are compared with respect to the average value of the amount of change in elliptical distortion, no significant difference is found under any of the circulation conditions.
However, paying attention to the maximum value of the amount of change in elliptical distortion, in the comparative product, the maximum value is 50 μm or more when the motor rotation speed is 70 Hz, compared with 30 Hz. On the other hand, in the example product, the maximum value is about the same regardless of the circulation condition.

From this result, in the comparative example product, a large change appears in the range of the amount of change in elliptical distortion according to the motor rotation speed which is the circulation condition of the quenching oil Y. It can be inferred that variations in the cooling rate occur in each of the outer rings constituting the structure. In other words, it can be said that in the comparative product, the difference in the circulation conditions affects the variation in the quality of the outer ring.
On the other hand, in the example product, the maximum value of the amount of change in elliptical distortion is stable regardless of the setting of the motor rotation speed, and it can be seen that the variation in quality is suppressed as compared with the comparative example product. . Moreover, in the example product, it can be estimated that the difference in the circulation condition hardly affects the variation in the quality of the outer ring.
As a result of the above tests, according to the example product according to the present invention, the flow of the quenching oil can be guided evenly with respect to a large number of outer rings regardless of the difference in the circulation conditions of the quenching oil Y. It was found that the variation can be suppressed.
Further, it goes without saying that the same effect can be expected not only for the annular member such as the outer ring described above but also for other mechanical parts other than the annular member.

  As described above, according to the result of the verification test, according to the quenching apparatus of the present invention, variation in the amount of deformation and distortion generated in the workpiece (annular member as an example of a large number of machine parts) increases. It became clear that it can be suppressed.

It is a schematic diagram which shows the structure of the hardening apparatus which concerns on one Embodiment of this invention. It is a perspective view which shows the aspect of the to-be-processed object mounted in the upper surface of a mounting base. FIG. 3 is a cross-sectional view taken along line III-III in FIG. 1. (A) is a top view of a mounting base, (b) is a bb arrow directional cross-sectional view in (a). It is a figure which shows the result of having performed simulation by making the state of the flow of the quenching oil in an oil tank into flow velocity distribution, (a) is an Example product, (b) is a result of a comparative example product. 4 is a graph showing the relationship between the amount of change in the elliptical distortion of the outer ring and the circulation condition of the quenching oil Y.

Explanation of symbols

1 Quenching device 5 Oil tank (cooling tank)
6 Transport device (lifting means)
6a Fork (support member)
6a1 Fork body (supporting part)
6a2 passage 7 circulation device (circulation means)
7c Discharge port 8 Mounting table 11 Current plate W Processed object w1 Annular member Y Quenching oil (coolant)

Claims (7)

A quenching device for quenching a workpiece,
A cooling tank in which a coolant for rapidly cooling the workpiece heated to the quenching temperature is stored;
A mounting table on which an object to be processed is mounted on an upper surface and the cooling liquid can pass in a vertical direction;
A support member configured to support a lower surface of the mounting table; and a passage through which the cooling liquid passes in a vertical direction, and the workpiece is transferred to the cooling liquid as the support member is lowered. Lifting means to immerse,
A discharge port for discharging the cooling liquid upward is provided at the bottom of the cooling tank, and the flow of the cooling liquid from the discharge port is immersed in the cooling liquid through the passage of the support member and the mounting table. Circulating to the discharge port after having led to the treated object,
The mounting table includes a rectifying plate that guides a part of the flow of the coolant passing through the passage to above the support portion of the support member. A quenching device for quenching a workpiece to be disposed three-dimensionally with a large number of annular members stacked,
A cooling tank in which a coolant for rapidly cooling the workpiece heated to the quenching temperature is stored;
A mounting table on which an object to be processed is mounted on an upper surface and the cooling liquid can pass in a vertical direction;
A support member configured to support a lower surface of the mounting table; and a passage through which the cooling liquid passes in a vertical direction, and the workpiece is transferred to the cooling liquid as the support member is lowered. Lifting means to immerse,
A discharge port for discharging the cooling liquid upward is provided at the bottom of the cooling tank, and the flow of the cooling liquid from the discharge port is immersed in the cooling liquid through the passage of the support member and the mounting table. Circulating to the discharge port after having led to the treated object,
The mounting table includes a rectifying plate that guides a part of the flow of the coolant passing through the passage to above the support portion of the support member.   The quenching device according to claim 1 or 2, wherein the current plate is provided in a state of being inclined with respect to a vertical direction.   The quenching apparatus according to claim 1, wherein the current plate is provided in a state where the current plate is inclined so as to be adjustable in angle with respect to a vertical direction. A method for quenching a workpiece,
Using the quenching apparatus according to any one of claims 1 to 4,
A method for quenching an object to be processed, wherein the object to be processed is placed on the upper surface of the mounting table, and the object to be processed is immersed in the cooling liquid as the support member is lowered. A cooling tank in which a coolant for quenching and quenching the workpiece heated to the quenching temperature is stored;
Elevating means for immersing the object to be treated in the cooling liquid as the supporting member descends;
An object to be treated is provided with a discharge port for discharging the cooling liquid upward at the bottom of the cooling tank, and the flow of the cooling liquid from the discharge port is immersed in the cooling liquid through the passage of the support member. And a circulation means that leads to the discharge port again, and a mounting table used in a quenching apparatus,
The lower surface is supported by the support portion of the support member,
The workpiece is placed on the upper surface and the cooling liquid can pass in the vertical direction,
A mounting table comprising a baffle plate for guiding a part of the flow of the coolant passing through the passage to above the support portion of the support member.   A mounting table used in the quenching method according to claim 5.

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