GB2070468A

GB2070468A - Method and apparatus for automatically inserting electrical connectors into housings

Info

Publication number: GB2070468A
Application number: GB8105266A
Authority: GB
Original assignee: Grote and Hartmann GmbH and Co KG
Current assignee: Grote and Hartmann GmbH and Co KG
Priority date: 1980-02-20
Filing date: 1981-02-19
Publication date: 1981-09-09
Also published as: GB2070468B; FR2476400B1; FR2476400A1; DE3006237A1; NL8100864A; DE3006237C2

Abstract

Several conductor ends (1,2,3, 4...8) are arranged in a holding block which is then conveyed to a crimping device where a portion of a respective connector 15 on a carrier strip 16 is crimped on to each conductor end. The connectors 15 are subsequently separated from the carrier strip 16 as a group by severing a piece 20 of the carrier strip with a knife 19 laterally to the direction of conveying. The connectors 15 on the piece 20 are then taken up by means of at least two conveyors such as 21 and are released by the holding block. The residual piece 20 of the carrier strip 16 is separated by a knife 24, and each conveyor is conveyed to a location confronting a housing where the crimped connectors 15 are pushed into openings in the housing. <IMAGE>

Description

SPECIFICATION Method and apparatus for automatically inserting electrical connectors into housings This invention relates to a method and apparatus for automatically inerting electrical connectors into housings, these connectors preferably being attached to highly flexible braided wire conductors.

Electrical connectors made from stamped sheet metal parts are usually connected to a carrier strip by a neck after being punched out and shaped.

They are coiled on to a spool with a carrier or waste strip in order to facilitate transportation and further processing. In order to crimp the connectors to the electrical conductors, the spool is arranged in a crimping device. There the connectors are wound off the spool and fed, on the carrier strip, to the crimping tool, the transporting means using the carrier strip for holding and guiding. In the crimping tool, the conductor is crimped to an electrical conductor, and, according to the known process, the carrier strip is simultaneously separated from the connector. To insert such a crimped connector into a housing, the conductor is gripped by suitable gripper elements behind the crimping point and, after opening of the crimping tool, conveyed to a position in front of an opening in the housing and then pushed into the housing.The gripper elements then free the conductor, ieaving the connector suitably positioned in the housing.

These known methods have in particular the considerable disadvantage that, on gripping the conductor after crimping, it cannot be ensured that the connector is aligned in the required manner so as to be capable of being pushed into the smallest opening of a housing without recentring and re-aligning. Even with relatively stiff conductors, it is not certain that the alignment is accurate enough, since it can occur that before crimping the end portion the conductor is not straight enough. When such an unaligned connector is pushed into position, it may catch on the corner of the opening so that the contact elements may become bent, or it may miss the opening in the housing and may then become bent along with the conductor, generally causing considerable interruptions in the functioning of the automatically operating device.

Furthermore, the known processes do not permit the automatic provision of housings with connectors using stiff conductors, whose end sections are intended to have a bend or other deformation. Such deformations, which may take place before or after crimping, prevent a conductor being gripped and guided while achieving the desired alignment of the connector.

Moreover, it is in particular not possible with the known processes to provide housings automatically with connectors which are crimped to flexible individual conductors, for example to flexible braided wire conductors. For, after gripping the conductor, the connector would hang uncontrollably in the air and could not be centred to the required degree and be pushed into an opening in the housing.

Specification No. 2,003,759A discloses a method and apparatus which enable connectors to be inserted into housings automatically,.

independently of the type of connector and conductor. The method comprises feeding a connector on a carrier strip to a crimping device, crimping a portion of the connector on to a conductor, feeding the crimped connector on the carrier strip to a connector gripper which grips and aligns the connector, separating the connector from the carrier strip, conveying the separated connector by the connector gripper to a location confronting an opening in a housing and pushing the connector into the opening. It is a characteristic feature of this method that, during and after crimping of the conductor, the connector is guided on the carrier strip and held there.By maintaining the connection between the carrier strip and the connector after crimping, it is possible to retain the carrier strip as a guiding element, and to grip and align the crimped connector, instead of the conductor, after opening of the crimping tool. The function of the carrier strip is then fulfilled, and it can be separated. The gripping and aligning of the connector enables the centred insertion of the connector into the housing opening.

It is advantageous if the gripper elements engage only with the crimped portion of the connector, so that the contact area of the connector remains free. This enables firstly the insertion of the contact area of the connector into the opening of the housing without involving any further process steps, and subsequently the pushing of the connector completely into the opening after opening of the connector gripper. It is also advantageous if the conductor is clamped in a location confronting the opening in the housing, the housing is pushed over the free contact area of the connector, and subsequently the crimped portion of the connector is freed from the connector gripper and the connector is completely pushed into the opening so that the conductor is held and clamped.Of course, it is also possible to first push the housing, then to grip the conductor and subsequently or simultaneously free the crimped portion. The only important thing is that the gripping takes place after the pushing, thereby enabling partial insertion of the connector into the housing. Furthermore, it is possible to push the contact part into the housing with the connector gripper, whilst the housing remains stationary, then to open the gripper and subsequently push the connector to the desired depth.

Separation of the-connector from the carrier strip can be carried out in an advantageous way if first the carrier strip is separated by being severed laterally to the conveying direction, leaving a residual piece of the carrier strip which is angled downwards (the connector and carrier strip being disposed generally horizontally during conveying), and subsequently the residual piece is cut off the connector. Preferably the angling down of the residual piece creates sufficient space below the conductor for a knife to be inserted in this space in order to sever the residual piece with a downward movement.

The method is therefore independent of the type of connector and conductor, since the gripping and aligning takes place on the connector and not on the conductor. The centring in front of the opening of the housing is only done with respect to the connector, independently of the type of conductor which is connected. Thus, with few new steps being taken, it has been possible to achieve a considerable advance.

Specification No. 2,003,759A also discloses apparatus for automatically inserting electrical connectors into housings, comprising a frame supporting a guide rail, a brake plate for controlling the feeding of connectors on a carrier strip along the guide rail, means for crimping a portion of each connector on to a respective conductor as the connectors are fed along the guide rail, a first knife system for severing each connector from the carrier strip after crimping, a second knife system for severing a residual piece of the carrier strip from each connector, a housing magazine for receiving the housings, a connector gripper for conveying each separated connector to a location confronting the housing magazine and inserting it into an opening in a housing in said magazine, and a conductor gripper for pushing the connector further into said opening.

The brake plate may be arranged above the guide rail in the vicinity of the carrier strip. The first knife system preferably consists of a cutting knife with a V-shaped blade arranged above the carrier strip transversely to the conveying direction, this blade being mounted in a knife holder which is connected to a piston-and-cylinder arrangement attached to the frame, and a stop limiting the downward stroke of the knife holder is rigidly mounted on the frame and a compression spring is provided between -the stop and the knife holder.

The second knife system can consist of a knife support, in which a vertical cutting knife is positioned with a knife head angled in the direction of the guide rail, the blade of which is arranged parallel to the conveying direction. By this means the knife support is connected to the piston-and-cylinder arrangement resting on the frame and the arrangement moves the support back and forth horizontally and at right angles to the conveying direction and vertically at right angles to the conveying direction.The connector gripper may comprise a narrow sliding chock having feet which stand on the guide rail and which is connected to a piston rod of the pistonand-cylinder arrangement attached to the frame, this arrangement serving to push the connector gripper over the guide rail in the conveying direction with the feet sliding on the guide rail, and the gripper having a gripping arm which can pivot around the axis positioned in the chock against the thrust of the spring, the gripping area of this arm having a recess which, together with one of the feet forms a conveying chamber. The conductor gripper and housing magazine preferably lie spaced apart in the conveying direction from the elements in the frame, the conductor gripper being arranged confronting, but spaced from, the housing magazine in a direction transverse to the conveying direction.Moreover, it is advantageous for a narrow bridge to be contained in this space between the housing magazine and the conductor gripper in the form of an extension of the guide rail which tapers at its end section, this bridge being slidable in the conveying direction on a neck piece attached to the frame, and producing a seamless connection between the two parts which essentially serve as a sliding basis for the connector gripper, the bridge having a shoulder against which one of the feet of the gripper abuts.

Furthermore, the conductor gripper may comprise a rigid arm which is attached to a block, and a pivot arm which is arranged so as to be pivotal around an axis positioned in a fork of the arm, preferably by means of a piston-and-cyiinder arrangement attached to the block, the block being connected to a piston-and-cylinder arrangement attached to the frame, which arrangement pushes the conductor gripper backwards and fowards horizontally and at right angles to the conveying direction. The housing magazine preferably holds the housing and is firmly mounted in a guide block which is held in a sliding block in which it can be moved vertically downwards.Moreover, the sliding block may be connected to a piston-and-cylinder arrangement attached to the frame, which arrangement pushes the housing magazine unit backwards and forwards horizontally and at right angles to the conveying direction.

It is an object of the invention to provide an improved method and apparatus for automatically inserting electrical connectors into housings, in which the insertion can be carried out particularly quickly and therefore the throughput capacity can be considerably increased, without the station time of the machine elements being significantly increased.

According to the invention there is provided a method of automatically inserting electrical connectors into housings, comprising arranging several conductor ends in a holding block, conveying the holding block to a crimping device, conveying connectors on a carrier strip to the crimping device, crimping a portion of a respective connector on to each conductor end, separating the connectors crimped on to the conductor ends from the carrier strip as a group by severing a piece of the carrier strip laterally to the direction of conveying, taking up the connectors on the severed piece of the carrier strip by means of at least two conveyors, releasing the conductors from the holding block, separating the residual piece of the carrier strip, conveying each conveyor to a location confronting a housing and pushing the crimped connectors into openings in the housing.

It is essential that the crimped connectors still lie on the carrier strip when they are passed to the conveyor. It is thereby guaranteed that the connectors are accepted by, for example, chambers of the conveyors in exact alignment, in which conveyors they rest, also in exact alignment, during the further stages of conveying.

The separation of the carrier strip is possible without impairing the alignment of the crimped connectors. It is furthermore advantageous for the conveyors to be capable of positioning the crimped connectors precisely in front of a housing chamber. According to one particular embodiment of the invention, conveyors are used which have chambers open at the front and back, so that they can be pushed on to the crimped connectors from the front, whereby they can simultaneously take up all the connectors from one piece of the carrier strip. The crimped connectors can then be individually pushed from a chamber in the conveyor forwards into a housing chamber which is positioned in front of the connector.

In order that the invention may be more fully understood, reference will now be made, by way of example to the accompanying drawings, in which: Figure 1 is a plan view of a block diagram illustrating a process according to the invention, Figure 2 shows a conveyor in front of a housing, Figure 3 shows diagrammatically the severing of the carrier strip.

Amongst other things, the process to be described is particularly suitable for crimping connectors on to multiwire telephone cables.

Therefore, in Figure 1, a cable 9 is shown which has four relatively soft conductors having ends 1, 2, 3 and 4 to which connectors are to be crimped.

The other ends of these conductors are also to have connectors crimped thereon and are therefore given the reference numerals 5, 6, 7 and 8. The conductor ends 1 to 4 provided with connectors are to be inserted into one housing, and the conductor ends 5 to 8 provided with connectors are to be inserted into another housing with four chambers. Of course, the invention is not limited to handling this particular number of conductors in a particular telephone cable; on the contrary, other problems can also be solved where very fast crimping of several conductor connectors and simultaneous insertion into several housings is required.

The ends 1 to 8 of the conductors are then fed by hand if necessary to a supporting block 10. The supporting block 10 is preferably positioned in such a way that it can hold all the conductor ends 1 to 8 of the cable 9, namely by suitable holding means (not illustrated) which preferably grip each conductor in such a way that is cannot be immediateiy withdrawn. Thereby the end portions of the conductors project above the conductor block 10 so that they can be handled.

Each supporting block 10 is fed to a transport system (not shown) which receives the supporting blocks in sequence a, b, c, d, e and so on, preferably without interruption, and conveys them in sequence in the direction of arrow 11. At 12, a precision cutting device can be provided which cuts the conductors 1 to 8 which have been positioned, if necessary, by hand in the supporting block 10, in their end area, so that all the ends 1 to 8 of the conductors projecting above the supporting block are brought to the same level of projection. Of course, this precision cutting is not necessary in all cases, but only has to be provided if exact positioning is not possible or can only be achieved at considerable expense.

In continuation of the process, the ends 1 to 8 of the conductors are then bared in sequence one after the other and crimped. For this purpose, a known type of stripping device is provided at 13, which is followed preferably some sequences later by a known type of crimping device at 14. This separation in sequence of the stripping and crimping operations is particularly advantageous since simple single-head devices can be used, which act on only one conductor at a time.

Varying crimping heights are therefore avoided, which can occur with multi-head equipment and which give rise to undesired varying extraction forces between the conductors and connectors.

Likewise, multi-head stripping devices can give rise to varying cutting levels, so that there is a residue from the stripping or strands are cut away, which also leads to varying extraction forces.

Connectors 1 5 (Figure 3) are fed in front of or into the crimping device and crimped, these connectors being arranged at a certain distance apart from each other on a carrier strip 16, each connector 1 5 being connected to the carrier strip 16 by a carrier neck 17, which is shown by way of example in detail in Figure 3. The supporting blocks a and b are not shown in Figure 3, in order to render the drawing easier to read. Only one guide rail 1 8 is shown.

The connectors 1 5 remain attached to the carrier strip 1 6 after crimping, as shown in Figure 3, and a cutting knife 1 9 is arranged above the carrier strip 1 6 at such a distance after the crimping device 1 4 that cutting of the carrier strip 1 6 can take place between two supporting blocks.

The cutting knife 1 9 is positioned so that a residual part 20 of the carrier strip remains with, in the present case, eight conductor-connector elements attached thereto, the carrier strip 1 6 being fed into the area of the supporting blocks by appropriate means (not shown), for example on guide rails. Guide seams (not shown) can be provided for this purpose on the carrier strip 16, ensuring that the carrier strip will run in a straight line without swerving, whereby the seams slide in corresponding grooves in the guide rails.

Before or during the cutting of the carrier strip 1 6 at 19 in Figure 1, two conveyors 21 and 22 are pushed on to the connectors from the front. The conveyors having chambers 23 which receive the connectors in a form-locking manner and keep them in a group. In the present embodiment, the two conveyors each have four chambers 23, whereby the first conveyor 22 receives the crimped conductor ends 1 to 4 and the other conveyor 21 receives the crimped conductor ends 5 to 8. After the conveyors have received the connector-conductor elements, the holding means of the supporting block 10 are opened and the conductor ends 1 to 8 are released; the supporting block is then withdrawn and can be used again.

Furthermore, the residual part of the carrier strip has now become superfluous and can be cut off with a knife 24 which severs the necks 17, the strip preferably first being bent downwards by suitable means so as to make space for the blade 25 of the knife 24, and the necks 17 subsequently being simultaneously severed. For this purpose, the length of the blade 25 corresponds to the length of the piece 20 of the carrier strip to be cut off. (In figure 3, the necks 17 are shown as having been broken off and not cut off so as to obtain a clear illustration.) The chambers 23 of the conveyors 21 and 22 are not only open from front to back, but also preferably open downwards, so that they have a slot 26 which, after the chambers have been loaded up, serves to release the conductors, as is described in further detail below.

After the residual part of the carrier strip 1 6 has been cut off, the conveyors 21 and 22 can be fed together to the front of a housing with, for example, eight chambers, whereby either the housing is brought horizontally in front of the conveyors and at right angles to the conveying direction, or the conveyors are brought into a vertical position, if the housing into which insertion is to be made has chambers arranged above each other. In both cases, however, the frames of the housing chambers must conform to the frame of the conveyor chambers. Then, by means of a pushing process using suitable means, all the connector-conductor elements can at once be pushed from the back forwards out of the chambers 23 into the housing or housings in the case where there are two or more housings.

Subsequently the conveyors are transported in such a way that the slots 26 release the conductors.

According to one particular embodiment of the invention, however, the two conveyors 21 and 22 are each guided to the front of a respective housing 27 or 28, which is shown in Figure 1.

Conveyor 22 is guided to the front of the housing 28 and conveyor 21 to the front of the housing 27. The housings are arranged in such a way that they can be moved in steps from a top position to a bottom position perpendicularly to the conveying direction of the conveyors, each step corresponding to the frame of the chamber of this housing. For insertion of the connectors into the housings, the conveyors are also moved stepwise in sequence, each step corresponding to the frame of the chamber of the conveyors. In this way, insertions can be made simultaneously into two or more housings.In the process a conveyor chamber 23 is conveyed to the front of a housing chamber, the connector-conductor element is pushed into the housing chamber by suitable automatic means pushing from behind, and the housing is then moved downwards one step, whereby the conductor 1 (Figure 3) slides through the slot 26 in the chamber 23, so that the connector-conductor element is positioned outside the conveyor 22.

It is therefore possible to make insertions much more quickly in several housings with varying chamber frames, without having to use several machines. The connector-conductor elements are particularly well positioned in the conveyors, so that no centring means are required for insertion into the housing chambers.

It is also possible to use single wire cables which as a rule are stripped by an automatic cross-cut machine and which can be fed individually directly to the crimping device. The supporting blocks are therefore not required.

Instead of these, only suitable holding and guiding means have to be provided for the carrier strip 1 6.

Claims

1. A method of automatically inserting electrical connectors into housings, comprising arranging several conductor ends in a holding block, conveying the holding block to a crimping device, conveying connectors on a carrier strip to the crimping device, crimping a portion of a respective connector on to each conductor end, separating the connectors crimped on to the conductor ends from the carrier strip as a group by severing a piece of the carrier strip laterally to the direction of conveying, taking up the connectors on the severed piece of the carrier strip by means of at least two conveyors, releasing the conductors from the holding block, separating the residual piece of the carrier strip, conveying each conveyor to a location confronting a housing and pushing the crimped connectors into openings in the housing.

2. A method according to claim 1, wherein the conductor ends are levelled and stripped immediately before crimping.

3. A methods according to claim 1 or 2, wherein the conveyors which are used have chambers open at the front and back and have a slot passing through the top or bottom.

4. A method according to any one of claims 1 to 3, wherein each conveyor is moved gradually to the side in one plane during insertion of the connectors and the corresponding housing is gradually moved downwards during insertion of the connectors.

5. A method according to any one of claims 1 to 4, wherein the severed piece of the carrier strip is bent downwards before the necks connecting this piece to the connectors are cut.

6. Apparatus for carrying out the method according to any one of claims 1 to 5, comprising supporting blocks for holding the conductor ends, a conveyor system for conveying the supporting blocks without interruption, a crimping device, holding and guiding means for the carrier strip of the crimped connectors, a cutting knife arranged above the carrier strip for separating the connectors from the carrier strip, conveyors which are provided for insertion of the connectors from the front and which incorporate chambers for receiving the connectors in a form-locking manner and holding them in a group, conveying means for conveying the conveyors, a knife device for separating the residual piece of the carrier strip, a conveying device for each conveyor for moving the conveyor to the front of a housing, the housings being arranged so that they can be gradually moved downwards.

7. Apparatus according to claim 6, wherein the conveying means gradually convey the supporting blocks.

8. Apparatus according to claim 6 or 7, wherein the conveying means for the conveyors transport both conveyors, which are arranged so as to lie against each other, simultaneously to the front of the knife device, and subsequently transport them further separately.

9. Apparatus according to any one of claims 6 to 8, wherein the length of the blade of the knife device corresponds to the length of the piece of the carrier strip which is to be cut.

10. Apparatus according to any one of claims 6 to 9, wherein there is provided, upstream of the crimping device, a precision cutting device which acts at right angles to the conveying direction in front of the supporting blocks, and a stripping device positioned after the precision cutting device.

11. A method of automatically inserting electrical connectors into housings, substantially as hereinbefore described with reference to the accompanying drawings.

12. Apparatus for carrying out the method according to any one of claims 1 to 5, substantially as hereinbefore described with reference to the accompanying drawings.