GB2206074A

GB2206074A - Crimping tool

Info

Publication number: GB2206074A
Application number: GB08714695A
Authority: GB
Inventors: W Barrie Hart
Original assignee: Cranfield Institute of Technology
Current assignee: Cranfield Institute of Technology
Priority date: 1987-06-23
Filing date: 1987-06-23
Publication date: 1988-12-29
Also published as: GB8714695D0

Abstract

A crimping tool for compressing terminals or connectors on the ends of electrical wires comprises two handle members (10, 12) interconnected by two crossed links (14, 16) which are pivoted together at a pivot point (18). The handle member (12) carries a fixed jaw (38) which cooperates with a movable jaw (40) formed on the facing end of a slide member (32) guided for sliding movement on the handle member (12). To make a crimp, the handle members are grasped and closed together, the handle members remaining substantially parallel, in contrast to known crimping tools which have pivotally movable handles which operate like pliers. <IMAGE>

Description

Title: Crimping Tool Field of the invention Thi invention relates to crimping tools which are used to comptess terminals ,r correctors or the ends Pf electrical wires.

Background to the invention Mots known crimping tools operate like hand-hold pliers, have pivotally movable handles which are g asped and brought together ir order to impart a crimping action between pivotally movable jaws of the crimping) tool. The plier action of such known tools is rot ergonomically satisfactory because the user's hand is forced to close around a wedye shape which is extremely uncomfortable at the start of the stroke. The object of the invention is to provide a crimping tool having handles mounted for relative movement in a manner which is more comfortable and ergonomically advantageous than the plier action of the prior art.

Summary of the invent ion According to the invention a crimping tool comprises two handle members, linkage means which interconnect the handle members and allow the latter to move towards or away from one another whilst remaining ir. substantially parallel side-by-side relationship, and a slide member connected to the linkage means and guided for sliding movement with respect to one handle member, the slide member carrying or being formed with a movable jaw cooperable with a fixed jaw on said one handle member, in use crimping dies being fitted to the jaws and the handle members being grasped and moved together to cause the slide member to move with respect to said one handle member to provide a crimping action. Hence, ir. a crimping tool according to the invention the handle members remain substantially parallel parallel to one anotner throughout their range of movement making operation more comfortable.

Also, because the slide member slides with respect to said one handle member, the jaw closing movement is parallel, rather tha:. pivoted as in the prior art.

The linkage means preferably omprise a-. X-linkage comprising two links pivotally interconnected at irtermediate points along their lengths, an extremity of one lir.k being pivotally connected to the slide member and the three remaining extremities of the two links being guided for sliding movement in the handle members.

Ratchet means may be provided to prevent opening movement of the handle members from an inter-mediate position in the range of movement of the handle members, ensuring that the user fully closes the handle members and completes a crimping action before the handle members can be opened ready for the next crimp. The ratchet means preferably comprise a ratchet carried by said one link and a springloaded pawl carried by the other link.

A crimping tool according to the invention will now be described by w3y of example, with reference to the accompa.yi.. drawings, in which: Figure 1 illustrates the crimping tool in an open position, F-igure 2 illustrates the crimping tool in a closed position, Figure 3 illustrates the crimping tool during opening movement of the handle members, Figure 4 illustrates the crimping:: tool during closing movement of the handle members, Figure 5 is an end view of the crimping tool in the direction of arrow A i. Fig,.rp 4. ad Figure 6 is ar. end view of the crimping tool in the direction of arrow B in Figure 4.

The crimping tool comprises two handle members 10 and 12 interconnected by an X-linkage consisting of two links 14 and 16 pivotally connected together at an intermediate pivot point 18. The handle member 10 has two slots 20 and 22 which guide respective pins 24, 26 on the ends of the links 14, 16. Hence, these ends of the links 14, 16 are guided for sliding movement in the handle member 10. The other end of the link 16 is pivotally connected at a pivot point 28 to the handle member 12. The other end of the link 14 is pivotally connected at a pivot point 30 to one end of a slide member 32 guided for sliding movement with respect to the handle member 12 by means of pins 34 projecting from the handle member 12 and slots 36 in the slide member 32.

The har.dle member 12 is formed at one end with a fixed jaw 38 which cooperates with a movable jaw 40 formed on the facing end of the slide member 32. A lazy link 42 interconnects the handle member 10 and the link 14 to maintain the handle members 10, 12 and the links 14, 16 in the correct planes during pivoting movement.

A knuckle-like protrusion 44 on the link 14 is formed witn a ratchet 46 t teeth Of which cooperate with a pawl 48 pivotally mounted on the link 16. The pawl 48 is spring- loaded towards tha position illustrated in Figure 1 by a spring 50. Further springes 52 and 54 bias the handle members 10 and 12 towards the oper. position show. ir.

Figure 1.

In use, crimping dies (.ot shown) having the appropriate profile are attached to the respective jaws 38 and 40.

The handle members 10 and 12 are sheathed by plastic handgrips (not shown) for comfort. Crimping is achieved by the user yr-aspir;g the handle members 10 and 12 and closing them together, as illustrated in Figure 4. During this closing movement the pawl 48 rides down the teeth of the ratchet 46 with attendant pivotal movement of the two links 14 and 16 about the pivot point 18 and consequent sliding movement of the movable jaw 40 towards the fixed jaw 38. If the user attempts to open the handle members 10 and 12 from an intermediate position such as that illustrated in Figure 4, the pawl 48 locks against the ratchet 46 to prevent such opening, unless the release lever 56 of the pawl is engaged to pivot the pawl 48 against its spring loading to disengaye the pawl from the ratchet.

The closed positions of the crimping tool is illustrated ir.

Figure 2, from which it will be seen that the handle members 10 and 12 lie in closely adjacent parallel relationship. When the handle members 10 and 12 have reached this fully closed position, the crimping dies will have applied a connector to a wire or wires and if the handle members 10 and 12 are then released the springs 52 and 54 move the handle members towards the open position, as illustrated ir. Figure 3. During this opening movement the pawl 48 rides along the ratchet teeth as the slide memner 32 undergoes sliding movement away from the fixed jaw.

It will be appreciated that the handle members 10, 12 remain in substantially parallel relationship throughout their range of relative movement, and that the jaw 40 approaches the jaw 38 with S rectilinear motion.

Figures 5 and 6 show that eauh handle member 10, 12 consists of two spaced plates iota, lOb, 12a, 12b, that the link 16 consists of two spaced plates 16a, 16b and that the slide member 32 consists of two spaced plates 32a, 32b. Figures 1 to 4 show one plate only of each of these two-plate components to reveal the positions of the links 14, 16 and the slide member 32. The two plates 16a, 16b receive between them a link 14, and the plates 16a, 16b are in turn received between the plates 10a, lOb. The end of the link 14 is received between the plates 32a, 32b which are in turn received between the plates 12a, 12b.

Claims

1. A crimping tool comprising two handle members, linkage means which interconnect the handle members and allow the latter to move towards or away from one another whilst remaining in substantially parallel side-by-side relationship, and a slide member connected to the linkage means and guided for sliding movement with respect to one handle member, the slide member carrying or being formed with a movable jaw co-operable with a fixed jaw on said one handle member, in use crimping dies being fitted to the jaws and the handle members being grasped and moved together to cause the slide member to move with respect to said one handle member to provide a crimping action.

2. A crimping tool according to claim 1, wherein the linkage means include an X-linkage comprising two links pivotally interconnected at intermediate points along their lengths, an extremity of one link being pivotally connected to the slide member, an extremity of the other link being pivotally connected to said one handle member and the two remaining extremities of the two links being guided for sliding movement in the other handle member.

3. A crimping tool according to claim 1 or 2, wherein ratchet means are provided to prevent opening movement of the handle members from an intermediate position in the range of movement of the handle members, ensuring that the user fully closes the handle members and completes a crimping action before the handle members can be opened ready for the next crimp.

4. A crimping tool according to claim 3, wherein the ratchet means comprise a ratchet carried by said one link and a spring-loaded pawl carried by the other link.

5. A crimping tool according to any of the preceding claims, wherein a spring or springs urge the handle members to an open position thereof.

6. A crimping tool constructed and arranged substantially as herein particularly described with reference to the accompanying drawings.