GB2067453A - Tool for mounting or removing a circlip, split ring of the like - Google Patents

Abstract

The tool is of the type comprising two branches (1 and 2) which are pivoted together. Each branch has at one end an interchangeable end member (17) which is adapted to engage in an aperture formed in one of the branches of the circlip. A link device (4) for regulating the distance between the end members is connected between the two branches (1 and 2) and serves to stress the circlip when it is mounted or removed. The length of the link device (4) is adjustable and the link device extends transversely of the branches. The axis X-X of the link device extends roughly in the general plane of the tool containing the branches. The length of the link device is adjusted by means of an element (15) which projects from both sides of the tool. <IMAGE>

Description

SPECIFICATION Tool for mounting or removing a circlip, split ring or the like The present invention relates to tools for mount ing and removing circlips, split rings or like ele ments.

It is known that circlips may be employed either "internally" or "externally". In the first case, the circ lip may retain an element inside a bore and is placed in an annular groove formed in the wall of the latter.

In the second case, the circlip may be used for mounting an element on a shaft and is for example placed in an annular outer groove provided in the shaft.

Tools exist for mounting or removing the circlip which are in the form of pliers and are specifically adapted to each aforementioned case. In order to enable a user to mount the two types of circlip, he would therefore need a set of two pliers one of which is operative in the opening direction whereas the other is operative in the closing direction. Further, these pliers must be provided with an adjustable stop in order to avoid exceeding the elastic limit of the circlip when mounting or removing it. Further, the user must hold the pliers under pressure in opposition to the action of a return spring when holding the circlip in its mounting or removing position.

The drawbacks of this type of tool have been partly overcome in a tool which was disclosed in the U.S.

patent No 3,365,582 and which enables the two types of circlip to be mounted and removed. This known tool comprises two branches pivoted together and each carrying at one end an interchangeable end member which is adapted to engage in an aperture formed in one of the branches of the circlip. It also comprises means connected between the two branches of the tool for adjusting the distance between the end members and stressing a circlip when it is mounted or removed. These adjusting means comprise a screwthreaded rod which extends longitudinally relative to the branches and which actuates the latter through two blocks and a set of two links, the rod also forming the handle for holding the tool after its adjustment. Consequently, the user needs both hands for adjusting the tool, which is inconvenient.

An object of the invention is to provide an improved tool of the type disclosed in the aforementioned U.S. patent which may be actuated in one hand.

The invention provides a tool of the aforementioned type wherein said adjusting means comprise link means which are of adjustable length and extend transversely of the branches of the tool, the axis of the link means extending roughly in the general plane containing the two branches and comprising a length adjusting element which projects from both sides of the tool.

With these features, the distance between the end members adaptable on a circlip may be adjusted by holding the tool in one hand and actuating the adjusting element, for example between the thumb and index finger.

Further features of the invention will be apparent from the ensuing description which is given solely by way of example with reference to the accompanying drawing in which: Fig. lisa plan view of the tool according to the invention; Figs. 2 and 3 are sectional views taken on lines 2-2 and 3-3 of Fig. 1; Fig. 4 shows the active end of two end members improved in accordance with the invention; Fig. 5 is an elevational view of two end members employed in the prior art, and Figs. 6 and 7 show respectively in elevation and in section an end member according to another embodiment of the invention.

In the embodiment shown in Figs. 1 to 3, the tool according to the invention comprises two branches 1 and 2 which are pivoted together by means of a pivot pin 3 which interconnects the branches at one end thereof. Roughly half-way along the length thereof, the branches 1 and 2 are interconnected by link means 4 of adjustable length and having an axis X-X which is roughly contained in the general plane containing the branches of the tool. In the illustrated embodiment, to which the scope of the invention is not intended to be limited, each branch preferably comprises two strips 1a, 1b, and 2a, 2b which are blanked from a sheet, the strips being identical in pairs. Close to the end opposed to the pivot pin 3, the strips are spaced apart by means of a collar 5 and rendered rigid with each other by means of a rivet 6.

A spacer plate 7 is provided at the opposite ends of the strips and has a hinge portion (not seen in the drawing) which has extending therethrough the pivot pin 3 and has a shape identical to the corresponding end of the strips 1b and 2a of the respective branches. Rivets 8 fix the spacer plate 7 between the strips la and 1b of the branch 1 and this plate freely extends between the strips 2a and 2b of the branch 2.

The middle part of each branch is notched internally in such manner as to provide a notch 9 for the link means 4. The latter comprise a first screwthreaded rod 10, pivotally mounted on the branch 1 by means of a rivet 11, a second screwthreaded rod 12, pivotally mounted on the branch 2 by means of a rivet 13, and an adjusting nut 14. The lattercomprises an actuating knurled wheel 15 which projects from each side of the tool. Note that the pivot end portions 10a and 12a of the screwthreaded rods 10 and 12 respectively are inserted between the corresponding strips of the branches 1 and 2. It will be understood that the screwthreads of the rods 10 and 12 have opposite hands in the same way as the independent tapped holes of the nut 14 which are not seen in the drawing.

The end of each branch of the tool opposed to the pivot pin 3 has on the inner side of the strips la, 1b and 2a, 2b V-section grooves 16 which extend lon gitudinally of the branches and are adapted to the hexagonal cross-sectional shape of the end mem bers 17. The latter terminate in finger portions 17a which are adapted to engage respectively in apertures formed in the branches of a circlip which must be mounted or removed. The end members are clamped between the strips of the branches 1 and 2 by means of clamping screws 18 which extend transversely of these branches. Consequently, the end members 17 may be removed and replaced by other end members in accordance with the work to be carried out The spacer plate 7 forms the male part of the hinge between the two branches which pivot about the pin 3.Further, the plate 7 has adjacent the branch 2 in which it is freely engaged a nose portion 19 which forms a stop when spreading the branches of the tool apart. This nose portion has an edge 20 which extends in a direction perpendicular to the axis of the link means, and a corresponding side face of the knurled wheel 5 of the link means 4 is capable of abutting this edge 20.

Although the branches 1 and 2 of the embodiment just described are made from blanked sheet metal, it must be understood that they may be formed in any other way, for example from forged steel or other parts.

A modification of the illustrated tool resides in the fact of providing the link means 4 for adjusting the distance between the end members 17 on the side of the pivotal interconnection of the branches opposed to that corresponding to these end members, without departing from the scope of the invention as defined in the appended claims.

As already mentioned, the end members 17 do not necessarily have the shape shown in Fig. 1. Conventionally, tools for mounting and removing circlips are provided with sets of end members so that the user can adapt his tool to the particular work to be carried out. According to the invention, each of these end members may be advantageously arranged as shown in Fig. 4 in which straight end members 17A are illustrated which terminate in a planar surface 21 perpendicular to their axis and a finger portion 17a-A for maintaining the circlip projects from this surface 21 in an eccentric manner. The end surface 2t has a relatively large area so as to provide a support for the respective branches of the circlip C which is as large as possible.In this way it is possible to avoid a twisting of the circlip which occurs with conventional end members as illustrated in Fig. 5. This twisting is disadvantageous from the point of view of the preservation of the shape of the circlip, above all if it is frequently mounted or removed.

The tool may be used in the following manner.

With the user holding the tool in one hand, the thumb is placed overthe knurled wheel 15 and the index is placed thereunder. In this way, the user can easily bring the ends 17a of the end member 17 in alignment with the apertures formed in the branches of a circlip or split ring. It is then merely necessary to rotate the wheel 15 to put a circlip which is to be removed under stress and thereby disengage it from the groove in which it was engaged. It will be understood that the tool may be employed for both types of circlip mentioned at the beginning of the description.

For the purpose of mounting a circlip, it may first be fixed on the tool by engaging the finger portions 17a in the apertures of the branches of the circlip and then put under stress. The circlip can then be placed in position while the wheel 15 is rotated by the hand which holds the tool.

The invention consequently provides atool for mounting and removing circlips which is easy to manufacture and may be used in one hand and whose end members are easily interchangeable. The specific end members shown in Fig. 4 provide an improvement in this respect in that they avoid the twisting of the circlip (Fig. 5). In view of the fact that the tool according to the invention is advantageously made from four blanked sheet metal strips which are identical in pairs, the tool is comparatively cheap.

Figs. 6 and 7 show another advantageous embodiment of the end members 17B which may be used to advantage with the tool shown in Fig. 1, i.e. a tool whose branches consist of two spaced-apart parallel strips.

Figs. 6 and 7 show by way of example the branch 1 of Fig. 1 between the strips 1a and 1b of which there is inserted a blanked sheet metal plate 17B which forms an end member. This plate has roughly the shape of a right angled trapezium whose parallel sides extend along the edges of the ends of the strips la and 1b. The inner edge of the plate has a notch 22 in which an indentation 23 formed in the strip 1b is engaged. The opposite edge of the plate or end member 17B has a finger portion 24 which is adapted to engage in a branch of the circlip. The remaining portion 25 of the edge may then act as a support for the circlip in the same way as the support surface 21 of the end member of Fig. 4. The plate 17B is rendered rigid with the strips la and 1b by means of a screw 18 which extends through an aperture 26 formed in the plate.

The end member of Figs. 6 and 7 may be very easily produced by blanking it from sheet metal. It may be employed advantageously with the tool of Figs. 1 to 3, although itis also possible to employ it with mounting and removing tools made from, for example, forged steel.

Claims (12)

1. Atool for mounting and removing a circlip, split ring or like element, of the type comprising two branches which are pivoted together and each carry at one end thereof an interchangeable end member which is adapted to engage in an aperture formed in one of the branches of the circlip, and means connected between the two branches of the tool for adjusting the distance between the end members and stressing a circlip when it is mounted or removed, wherein said adjusting means comprise link means which are of adjustable lerigth and extend transversely of the branches of the tool, the axis of the link means extending roughly in the general plane containing the two branches and comprising a length adjusting element which projects from both sides of the tool.

2. Atool according to claim 1,wherein said link means comprise two rods which have reversed screwthreads and are respectively pivotally mounted on the branches and interconnected by an adjusting nut which has corresponding reversed screwthreads, said nut being provided with a wheel which projects from both sides of the tool.

3. Atool according to claim 2, comprising a stop for limiting the distance between said branches, said stop being rigid with one of said branches and disposed in confronting relation to a side of said wheel which faces the other of said branches.

4. Atool according to claim 1,2 or 3, wherein said branches are pivoted together at one of the ends thereof and said link means are connected to said branches at substantially half-way along the length thereof.

5. Atool according to any one of the preceding claims, wherein each of said branches is made from blanked sheet metal.

6. Atool according to claim 5, wherein each branch comprises two identical strips which are substantially wholly coextensive and are rendered rigid with each other with interposition of spacer means therebetween.

7. Atool according to claim 6, wherein one of the spacer means comprises a spacer plate which extends between said link means and the pivotal connection of said branches, said plate being rigidly fixed between the strips of one of said branches and extending freely between the strips of the other of said branches while it constitutes by an end portion thereof the male part of a hinge which forms the pivotal connection of said two branches.

8. Atool according to claims 3 and 7, taken together, wherein said stop is formed on a nose portion of the spacer plate.

9. Atool according to any one of the claims 4 to 8, wherein said end members are fixed between the respective strips of said branches and held in position by screws which extend through said strips.

10. Atool according to any one of the preceding claims, wherein the end members comprise finger portions of reduced section which extend the end members and are adapted to engage in apertures of the respective branches of a circlip, split ring or the like, each end member being widened adjacent to the finger portion having a transverse support surface from which the finger portion extends in an eccentric position.

11. Atool according to any one ofthe claims 1 to 9, wherein each end member is made from a blanked sheet metal plate and a finger portion which is adapted to engage in an aperture of a branch of a circlip, split ring or the like, extends from one of the edges of said plate.

12. Atool for mounting and removing a circlip, split ring or the like, substantially as hereinbefore described with reference to and as shown in Figs. 1, 2 and 3, or Fig. 4, or Figs. 6 and 7 of the accompanying drawing.