DE19725597A1 - Pliers to fit or remove circlips for shafts and bores - Google Patents

Abstract

The pliers have left and right grip levers (2,3) and a central shaft (6) for turnable holding of overlapping carrier sections (2a,3a) of the front grip parts. Helical springs (9) pretension the lever sections into open positions. Central sections of left and right operating levers (10,11) are held turnable between the carrier sections, so that they coaxial with the central shaft. Left and right front plier sections (27,35) are fitted into guide sides of the operating levers, and each has a curved circlip holder part (39,40). A switching device switches between a shaft operating position, in which the holder parts are moved apart, and a bore operating position, in which they are moved together. The front plier sections consists of a shape memory alloy.

Description

Technical field

The present invention relates to pliers for insertion and removing a circlip for a shaft in or from a shaft groove as well as for insertion and removal a circlip for a hole in or out of an in a hole in the hole.

State of the art

Pliers for inserting or removing circlips basically divisible into two groups. The one group includes the pliers, which are specially designed to Insert the shaft retaining rings in a shaft groove or remove from this by the distance between the two Ends of the shaft locking ring is expanded. The other Group includes pliers specially designed to a circlip for a hole in a groove in one Insert or remove the hole by using the Distance between the two ends of the circlip is reduced.

The specifically for inserting or removing a Shaft retaining ring designed pliers includes each other symmetrically arranged levers, each continuous from a retaining ring retaining part on one front to one Handle portion are formed on a base and each essentially a kinked shape or shape  exhibit. The levers are connected so that the two retaining ring holding parts are parallel to each other, the lever bend sections being rotatable relative to one another are stored. Both circlip holding parts are after curved outside, d. H. in the direction in which it is point away from each other. When using the pliers, the Circlip holding parts in at both ends of one Circlip inserted holes and then through Squeezing the handle sections away from each other, so that the distance by means of the retaining ring holding parts enlarged between the two ends of the circlip becomes. Because of this, the circlip Holding parts of the locking ring held securely at the holes and the locking ring cannot be removed from the Slip the circlip retaining parts. This is a correct insertion or removal of the circlip in or possible from a shaft groove.

The specifically for inserting and removing a fuse ring designed for a hole has a right and left levers, each with the front end a retaining ring holding part and on a base with are provided with a handle. The levers cross in a kind of X-shape and are in the overlap area to each other rotatably connected. Both circlip retainers are curved inwards, d. H. in the direction in which it is are movable towards each other. When using the pliers the circlip holding parts in turn in the holes of the Circlip inserted and then by squeezing the handle sections moved towards each other, so that by means of Circlip retaining parts the distance between the two Circlip ends is reduced. That is again by means of the retaining ring holding parts, a secure holding of the Circlip at the holes possible and it will be Prevents slipping out, which ensures secure attachment or remove the circlip for a hole in or from a groove in a hole is possible.  

However, these known pliers have the disadvantage that they are not both for a circlip for a hole can also be used for a circlip for a shaft are.

In order to remedy this disadvantage, pliers for attaching or removing a retaining ring for both a shaft and for a bore have been proposed, in which it is possible to switch back and forth between the two operating positions by using right and left movable pins 101 , 102 in each case opposite direction, as disclosed, for example, in U.S. Patent No. 4,476,750 (see also Figs. 18 and 19).

On the one hand, these pliers can be locked in a so-called shaft operating position by coupling a right actuating lever 103 by means of a right movable pin 101 with a right handle lever 104 or positive locking between them, and in which a left actuating lever 105 by means of a left movable pin 102 is coupled to a left handle lever 106 , whereby the left and right actuating levers 103 , 105 are moved away from one another by compressing the left and right handle levers 104 , 106 and rotating them about a holding axis 107 .

On the other hand, these pliers can be fixed in a so-called bore operating position in that the left actuating lever 105 is integrally or positively coupled with the right handle lever 104 by means of the left movable pin 102 and the right actuating lever 103 with the left one by means of the right movable pin 101 Handle lever 106 is coupled, whereby the left and right actuating lever 103 , 105 are then moved towards each other by compressing the two handle levers 104 , 106 .

Accordingly, it is possible with this device, depending on the specified operating position, to move the two retaining ring holding parts 108 , 109 of the left and right actuating levers 103 , 105 towards and away from one another, so that both retaining rings for a bore can be moved with these single pliers as well as circlips for a shaft can be attached and removed.

It should be noted, however, that to attach or remove a circlip for a shaft, the circlip holding parts 108 , 109 described above should be curved outwards, ie pointing away from each other, and in the event that a circlip for a bore is attached or to be removed, the retaining ring holding parts 108 , 109 should be curved in directions directed towards one another. If the alignment of the retaining ring holding parts 108 , 109 is not predefined in a suitable manner, there is a risk that a retaining ring will slip and jump off the retaining ring holding parts 108 , 109 and be lost.

For this reason, according to the type of the circlip (either for a bore or for a shaft), the pliers shown in FIGS . 18 and 19 are set in the bore or shaft operating position by the right and left circlip holding part 108 , 109 is rotated about its longitudinal axis by 180 °. To change this type of pliers, three activities must be carried out on the two retaining ring holding parts 108 , 109 :

• (1) loosening screws 110 , 111 which fix the retaining ring holding parts,
• (2) Turn the retaining ring holding parts by 180 ° and
• (3) Tighten the screws 110 , 111 to fix the circlip retaining parts again. Furthermore, to move these pliers, it is also necessary to press both movable pins 101 , 102 into the corresponding position. Both a circlip for a hole and a circlip for a shaft can be attached or removed with this single pair of pliers, however the changeover is cumbersome and time-consuming.

In order to overcome the problem explained above, the Applicants for this application have previously pliers suggested switching between the Operating position for a circlip for a shaft and the operating position for a circlip for a Drilling can be performed with a single operation can (Examined Japanese Patent Publication Hei 7-49186, US no. 5,542,167 and unexamined Japanese Patent Publication No. Hei 8-112778, etc.).

This pair of pliers is set in the bore operating position for a circlip for a bore by rotating the left and right pliers front so that the left and right pivot shafts and the movable pins lock each other, thereby causing the left operating lever and the right handle lever and the right operating lever and the left handle lever are coupled to each other by the left movable pin and the right movable pin. Furthermore, with this pliers, the operating position for a circlip for a bore is to be set such that when the circlip holding parts are directed outwards, the right actuating lever and the right grip lever and the left actuation lever and the left grip lever by means of the right movable pin or of the left movable pin can be locked coupled together (see Fig. 17).

Furthermore, the pliers described above respective front part of the pliers can be designed interchangeably and according to the variety of necessary settings for different types of circlips are the circlip Holding parts designed differently or there are  various pliers front parts from small to medium size available, according to the Circlip type to be attached or removed are specially designed.

This applicant's already known pliers has the remarkable advantage that only by means of a Handling, namely twisting the left and right Pliers front part, it is possible to Holding parts in the front parts of the pliers and the left and right lever either in an operating position Attaching or removing a circlip for one Bore or in an operating position for attachment or removing a circlip for a shaft to be able to adjust. However, there are others here as well Improvements as explained below helpful.

So z. B. each specifically to the number of various attachment and removal positions and Circlips of various sizes adapted Pliers front part exchangeable. This improvement however, increases manufacturing costs because left and right Pliers front parts in a variety of designs have to be manufactured. It is also for a user imperative, a variety of left and right Store the front of the pliers and always have them ready. In addition, both parts of the pliers must also be replaced will.

These pliers previously proposed by the applicant includes an embodiment in which the left and right The front part of the pliers each has a retaining ring holding part includes that extends at right angles. At Use of such circlip holding parts acts during the use of pliers equipped in this way probably a moment of force in the direction in which the  Turn the circlip holding parts around their longitudinal axis so that there is a tendency for the position to change Circlip holding parts is effected.

Furthermore, it is with regard to various Circlip sizes possible, the circlip holding parts to be exchanged accordingly on the front parts of the pliers. It is however necessary when the two handle levers are pressed together control the application of force in a suitable manner. Because attaching or detaching a small one Circlip is of course different from that Attaching or removing another, for example larger circlip with regard to the expansion or Compression path length of the two retaining ring holding parts. You usually try to squeeze the force Check both handle levers so that a suitable one Expansion or compression area of the circlip Holding parts can be checked. However, there is the danger that the force to squeeze the two Handle lever not according to that of the circlip required degree can be controlled so that a Circlip expanded or expanded too much is squeezed.

Presentation of the invention

The present invention has been made in view of the foregoing described circumstances. That of the invention underlying technical problem is a To provide novel pliers that can be used in many ways and also for different sizes of circlips can be used without the front parts of the pliers each time need to be replaced.

This technical problem is solved with a pair of pliers Feature of claim 1 solved.  

Such pliers have the advantage that regardless of the Size of the circlip to be attached or removed the same pliers can always be used and also none Replacement of the front parts of the pliers is more necessary as this are each adaptable to the respective type of circlip. At an advantageous embodiment also ensures that the two snap ring holding parts in one of the size of the circlip corresponding movement range operated become, d. H. the circlips are not overused will. In addition, such pliers with regard to Manageability, practicality and usability outstanding.

The configuration described above includes advantageously also a switching device with which the basic operating positions, d. H. between Operating positions for attaching or removing a Circlips for a hole or for a shaft free can be switched so that when squeezing the two handle levers either the two circlip Holding parts moved away from each other or in the Operating position for a circlip for a hole the two retaining ring holding parts are moved towards each other will. Since the two pliers front parts from one Shape memory alloy (memory alloy) can exist the locking ring holding parts by means of a suitable Tools, such as a teaching, a kind Keys or the like, at the front ends in suitable Be deformed way, causing the retaining ring holding parts to a wide variety of attachment and removal positions and states as well as various Circlip sizes are adaptable accordingly. After this The circlip holding parts are used Immerse in hot water at a predetermined temperature warmed, causing them to return to their initial shape,  d. H. back to its initial state or original shape take in.

The present invention further includes one second aspect an adjustment device, which in is suitable in many ways, an opening angle between the two handle levers taking into account the Spring force as well as the closing angle between them too check when the two handle levers are pressed together will.

Checking the opening angle between the two Handle levers is that the maximum opening angle between the two handle levers by the spring apart, can be adjusted. The Check the closing angle between the handles in setting the minimum closing angle between if the two handle levers are pressed together, d. H. to be able to set the compression path.

It is in the embodiment according to the second aspect possible by means of the setting device, the opening like also determine the closing angle in a suitable manner, which when pressing the two handle levers against the Spring force as well as when releasing the handle lever the free Path length of the two retaining ring holding parts automatically within one of the type and size of a suitable circlip to be removed can be controlled.

The setting device can be designed in any way as long as the opening as well as the closing angle between the two handle levers is adjustable can be designed or controlled.

As an alternative to this, for example, a Screw thread movable element (advantageously a  Knurled nut) present, which is in contact with and engaged with a Inside edge of the right handle can be brought to the Check the closing angle of the two handle levers. Of another is another by means of a screw thread movable element (other knurled nut) with a Outside edge of the right handle lever in contact and Can be brought to the opening angle of the two Check handle lever. Both elements are in one Threaded rod movable back and forth, the cantilever-like attached to the left handle lever Base section is held so that its Protrudes beyond the right handle lever, whereby the movable elements are movable so that they the opening and closing angle by adjusting the limit the appropriate position accordingly.

An alternative embodiment of the setting device according to a third aspect includes a right engaging portion, which is present on the right handle lever and a left one Engagement portion which is provided on the left handle lever. The left engagement portion includes an operating lever that with a boom attached to the left handle lever Base section is held so that the front end over the right handle lever protrudes. A threaded rod is in the Intermediate section of the control lever attached. A back and forth The screwable element is in contact with the inner edge the right handle can be brought to the closing angle of the limit both handle levers. A number of tabs are at predetermined intervals in the longitudinal direction of the Control lever provided to right Engagement section to engage so that the Opening angle of the two handle levers can be limited. With this advantageous embodiment, the actuation according to the second aspect flawlessly with relatively simple Design are carried out and the setting of Setting up is very simple.  

If the base section of the control lever on the left handle lever is removably attached, such as by Screw tight, positive or non-positive or like, the left engaging portion can be applications correspond without the setting with the Adjustment device is necessary. If the right one Engagement section previously formed on the right handle lever is, or on the right handle lever by fasteners, such as for example screwing, fitting or the like on right handle can be attached, the right Intervention section also retrofitted to a conventional one Pliers that are not attached with a Adjustment device is equipped.

In all embodiments according to the first to third Aspects, the switching device is not on the actual training as described here limited, but any configuration is applicable, as long as an operating setting for one Circlip for a shaft and an operating setting adjustable for a circlip for a hole or toggle between these positions can. However, it is preferred to use pliers proposed, which has already been proposed by the applicant (Japanese Patent Examined Publication No. Hei 7-49186, US 5,542,167 and Japanese Unexamined Patent Publication No. Hei 8-112778).

The essential design of the switching device will described below.

Right and left pliers front parts 27 , 35 are rotatably and interchangeably attached to left and right operating levers 10 , 11 . A right movable pin 20 , which can be brought into engagement with one of the right engagement holes 15 , 16 in both support sections 2 a, 3 a, is present in a pin hole 19 of the right actuating lever 10 . A left movable pin 22 , which can be brought into engagement with one of the left engagement holes 16 , 18 in the two support sections 2 a, 3 a, is present in a pin hole 21 of the left actuation lever 11 . A right and a left rotary shaft 24 , 32 , which can be positively rotated together with the right and left pliers front part 27 , 35 , is created in the right and left actuating lever 10 , 11 so that the right and left movable pin 20 , 22 can be brought into engagement with one of the right engagement holes 15 , 17 or with one of the left engagement holes 16 , 17 . The right and left rotary shafts 24 , 32 are operatively connected to the respective movable pin 20 , 22 . The operating position for a circlip for a bore can then be adjusted by turning the two pliers front parts 27 , 35 in such a way that the circlip holding parts 39 , 40 point inwards, the left actuating lever 11 and the right grip lever 2 and the right actuating lever 10 and the left handle lever 3 are positively coupled via the left movable pin 22 and the right movable pin 20, respectively. To set the shaft operating position for a circlip for a shaft, the circlip holding parts 39 , 40 are turned outwards, the right actuating lever 10 and the right grip lever 2 as well as the left actuation lever 11 and the left grip lever 3 via the right movable pin 20 or the left movable pin 22 are positively coupled to each other.

With the above configuration, the two Circlip holding parts are turned outwards, whereby both retaining ring holding parts pointing away from each other Direction are curved. Here, the two pins that each via a gear section with one of the two Combing rotary shafts, moving in opposite directions, whereby the right movable pin over the pin hole of the right operating lever and the engagement hole of the right grip lever engages and the left  movable pin over the pin hole of the left Operating lever and the engagement hole of the left Handle lever engages. In this position right operating lever and the right handle lever as well as the left operating lever and left handle lever over the right movable pin or the left movable pin positively connected with each other, that is coupled with each other. If now the two handle levers are pressed together, both ends become one by means of the Circlip retaining parts held for a circlip Shaft away from each other and the circlip can in a shaft groove is inserted or removed from it.

In the other case, the right and left circlip Holding part turned inwards and both circlips Holding parts are curved towards each other. In In this position, the right movable pin and the left movable pin, with their respective Comb gear sections with the respective rotary shaft, in the opposite of the operating position described above Direction twisted, causing the left movable pin over the pin hole of the left control lever and over that Engaging hole of the right handle lever engages and the right movable pin over the pin hole of the right Operating lever and the engagement hole of the left Handle lever comes into engagement. With this setting are the left control lever and the right grip lever as well the right control lever and the left handle lever over the left movable pin or the right movable pin operationally linked. Now if the two Handle levers are squeezed together by the Circlip retaining parts held ends Circlip for a hole moves towards each other, and the locking ring can thus be in a groove in a bore used or removed from it.  

Thus, the basis of the invention technical problem due to this geometric effect, such as he described above is a very beneficial one Embodiment created like that in the first to Functions created third embodiment achievable.

According to a fourth aspect, the present invention characterized by the features of claim 4.

With this configuration, it is in addition to the functions and effects of the pliers previously described by the applicant (Japanese Patent Examined Publication No. Hei 7-49186, U.S. Patent 5,542,167 and Japanese Unexamined Patent Publication No. Hei 8-112778) possible Check the rotation of the front parts of the pliers in order to Positional deviation of the circlip retaining parts prevent. The two front parts of the pliers can pass through optionally setting a first setting position in which one Twist is locked, and in a second setting position can be set in which a free rotation is possible. The attachment or removal of a circlip is in the first setting position. In this first one The setting position is then the rotation of the front parts of the pliers blocked so that twisting of the front parts of the pliers is not is possible. Accordingly, there is no position deviation as possible with the prior art. If the Pliers front parts are rotated into the second setting position, the pliers can move freely into an operating position for one Circlip for a hole or in a shaft Operating position to be changed.

According to a fifth aspect, the present invention advantageously by the features of claim 5 featured.

With such a design of pliers according to the invention is a two-stage locking device, in which in  the first and in the second setting position of the two Pliers front parts the locks in the first and second Snap recesses into place, thereby switching between the first setting position and the second setting position easily and can be carried out correctly. The Prevented shank sections of the pliers front parts from the guide holes slip out, causing the twist coupling can be maintained with the rotary shafts. This prevents but not that the forceps front parts by strong Pull out completely and be replaced can.

In an advantageous embodiment with regard to a sixth aspect of the present invention are right and left pliers front parts for attaching or detaching a Snap rings (especially a benzing circlip), rotatable and detachable on the two operating levers intended. The front of the pliers for one special circlip can be used instead of the first Pliers front parts can be replaced.

In the above configuration, the front parts of the pliers are for Attaching or removing a benzing circlip to the attached to both operating levers. These front pliers are in the operating position for a circlip for set a hole, d. H. the inner arches of the Circlip holding parts are aligned with each other. It is also possible to close the front of the pliers by 180 ° turn and the operating position for a circlip for set a shaft where the inner arc surfaces the front of the pliers are facing away from each other (the outer flat surfaces are directed towards each other).

When inserting a circlip for a bore, a circlip retaining part is placed with its inner arc surface on the outer circumferential surface of the shaft, while the other circlip retaining part is placed with its inner arc surface on the outer circumferential surface of the benzing circlip to be fitted on the shaft. Then the two handle levers are pressed together so that both circlip holding parts are moved towards each other, whereby the circlip is placed on the outer circumferential surface of the shaft. In the other case, the operating position for a shaft is selected and a circlip retaining part with its inner arc surface is placed on the outer circumferential surface of the shaft, while the other circlip retaining part is placed on the shaft with its inner arc surface on the inner circumferential surface of the benzing circlip. Then, by pressing the two handle levers together by means of the two retaining ring holding parts which are moved away from one another, the retaining ring is pulled off the shaft. However, it is also possible to pull off the benzing circlip from the shaft by clamping part of the circlip (benzing rings) placed on the shaft between the circlip holding parts, with the outer flat surfaces facing each other and by clamping the circlip this from the shaft is withdrawn (see Fig. 10c and 10d).

Brief description of the drawings

The following are for further explanation and for better Understanding the invention under several embodiments Reference to the accompanying drawings described in more detail and explained. It shows:

Fig. 1 is a plan view of a first embodiment of a chuck (generally attachment and Abnehmewerkzeug) according to the present invention, wherein an intermediate part of the handle lever is omitted,

Figure 2 is an enlarged cross-sectional view taken along line (A) -.. (A) in Fig 1,

Fig. 3 is a plan view of main parts of a forceps according to the invention, wherein a position for mounting or removal is set a retaining ring for a hole with a medium size,

Fig. 4 is a plan view of components of the forceps according to the invention for fitting or removing a retaining ring for a bore having a small size,

Fig. 5 is a plan view of components of the forceps according to the invention for fitting or removing a retaining ring for a bore of an intermediate size,

Fig. 6 is a perspective view of a front part of pliers using a teaching / shows the process for changing the shape of apparatus,

Fig. 7 is a plan view of main parts of an embodiment of the invention, wherein a position for attaching / detaching an E-ring is set (Benzing circlip)

Fig. 8 is a sectional view of main parts of an embodiment of the present invention showing the assembly process of an E-ring,

Fig. 9 is a plan view of main parts of an embodiment of the invention in which a position is determined for removing an E-ring,

Fig. 10 is a cross sectional view and a perspective view of main parts of an embodiment of the invention that an E-ring showing the removal,

Fig. 11 is a plan view showing a switching means for switching between a shaft and a bore-operating position, wherein an adjusting means is omitted,

Figure 12 is an enlarged cross-sectional view taken along line (B) -.. (B) of FIG 11,

13 is an enlarged cross-sectional view taken along line (C) -.. (C) of FIG 11,

Fig. 14 is an enlarged partial cross-sectional view according to Fig. 11,

Fig. 15 is an enlarged partial cross-sectional view showing another embodiment of a lock (stop),

Fig. 16 is an enlarged partial perspective view showing a connection between a pliers front part and a rotary shaft,

Fig. 17 is a perspective view showing a state in which turned around the forceps and front parts are changed for a collar for a hole or for a shaft,

Fig. 18 is a plan view showing a conventional clamp (means) for attachment and removal of a retaining ring for a shaft or a bore, and

19 is an enlarged cross-sectional view taken along the line (D) -. (D) in Fig. 18.

Description of exemplary embodiments of the invention

The various embodiments are hereafter in described in more detail.

In an illustrated apparatus 1 (pliers) are located overlying support portions 2 a, 3 a rotatably supported a right and left handle lever 2, 3 via a supporting axis. 6 The supporting axis 6 runs through bores 4 , 5 in both front parts of the pliers. A coil spring 9 is mounted between opposite projections 7 , 8 of the two levers 2 , 3 . Due to the spring force of the spring 9 , the two handle levers 2 , 3 are biased about the supporting axis 6 , so that they assume a position in which they are apart in an approximately inverted V. If the two handle levers 2 , 3 are pressed together against the spring force of the springs 9 , both handle levers 2 move towards one another. When the pressure drops, the spring force of the spring 9 moves the two handle levers 2 , 3 away from each other and opens.

An adjusting device is provided between the two support sections 2 a, 3 a, and the spring 9 provided in the two handle levers 2, 3, so that a closing and an opening angle of the handle lever 2 can be adjusted in many ways 3 and controlled. The setting device will be described in detail later.

An exemplary embodiment of a switching mechanism is described with reference to FIGS. 11 to 17, which can only be freely changed by turning the two right and left pliers front parts 27 , 35 , which will be explained in detail below, and with retaining ring holding parts 39 , 40 of the two pliers front parts 27 , 35 of the respective handle levers 2 , 3 can be set both for attaching and removing a retaining ring for a bore and for attaching and removing a retaining ring for a shaft. The adjustment mechanism is omitted for the sake of explanation.

A basic lever section 10 a of a right operating lever 10 and a basic lever section 11 a of a left operating lever 11 are arranged parallel to one another between the overlapping supporting sections 2 a, 3 a. Semicircular shaft recesses 12 , 13 , which are formed on opposite sides of the two basic lever sections 10 a, 11 a, are freely inserted in shaft bores 4 , 5 and the holding axis 6 passes through a shaft bore 14 which is formed between the shaft recesses 12 , 13 . The two actuating levers 10 , 11 are pivoted about the holding axis 6 , namely between a position in which the front lever sections 10 b, 11 b are parallel, and a position in which they are open in an approximately V-shape.

On the support section 2 a, right and left engagement bores 15 , 16 are formed in two corners of a triangle, which has the shaft bore 4 as a tip. Similarly, the supporting portion 3 a in two corners of a triangle, which has the shaft hole 5 as the top, right and left engaging holes 17 formed 18th A right movable pin 20 , which is held in a pin hole 19 of the right base lever portion 10 a, is axially movable and releasably engageable with one of the two engagement holes 15 17. Whereas a left movable pin 22 , which is held in a pin hole 21 of the right base lever portion 11 a, axially movable and with one of the two engagement bores 16 , 18 in engagement - in a detachable manner.

The right operating lever 10 has a guide hole 23 which goes from the pin hole 19 to the front edge of the lever 10 .

A rotary shaft 24 is received in the guide hole 23 . A gear portion 25 formed at the base end of the right rotary shaft 24 protrudes into the pin hole 19 and meshes with a rack portion 26 of the right movable pin 20 so that the right movable pin 20 is moved by rotating the rotary shaft 24 in the pin hole 19 . A shaft section 28 of a right front part 27 of the pliers is detachably and rotatably inserted in the guide hole 23 . An engaging groove 29 at one end of the shaft section 28 engages with an engaging projection 30 , which is created on a front side of the right rotary shaft 24 , so that it can be positively rotated therewith.

In the same way, a left rotary shaft 32 is received in a guide hole 31 of the left operating lever 11 . A gear section 23 , which is provided at the base end of the left rotary shaft 32 , meshes with a rack section 34 of the left movable pin 22 . A shaft portion 36 of the right front pincer 35 is inserted in the guide hole 31 . An engaging groove (connecting portion) 37 formed at one end of the shaft portion 36 is engaged with an engaging protrusion (an engaging protrusion) 38 formed on the front side of the left rotary shaft 32 so as to be engaged therewith is positively rotatable.

The type of connection between the engagement groove 29 of the right pliers front part 27 and the holding projection 30 of the right rotary shaft 24 and the connection between the engagement groove 37 of the left pliers front part 35 and the retaining ring holding part 38 of the right rotary shaft 32 are each designed as a type of plug connection, wherein a connection angle around an axial connection line is specified as a removal or attachment angle, in which the two retaining ring holding parts 39 , 40 (described below) are directed inwards or outwards.

Because of this, the engagement projections 30 , 38 are formed in an eccentric manner somewhat to the longitudinal axis of the rotary shafts 24 , 32 , while the engagement grooves 29 , 37 are somewhat eccentric with respect to the longitudinal axis of the shaft sections 28 , 36 , so that the engagement projections 30 , 38 engage can reach. By resetting the pliers front parts 27 , 35 , they can be fixed correctly and precisely in a position in which both the right and the left retaining ring holding parts 39 , 40 are directed inwards or outwards.

The right front part of the pliers 27 has a retaining ring holding part 39 on its front end piece, which is essentially curved with respect to the longitudinal axis. The right front part of the pliers 27 can be changed by a 180 ° rotation between a position in which the retaining ring holding part 39 is directed outwards and a position in which it points inwards. In the same way, the left pliers front part 35 is equipped with a retaining ring holding part 40 at its front end piece. The left pliers front part 35 can in turn be changed by a rotation through 180 ° between a position in which the retaining ring holding part 40 is directed outwards and a position in which it points inwards.

The connection between the right pliers front part 27 and the right movable pin 20 is as follows. Similarly, when the right pliers front part 27 is rotated 180 ° clockwise or counterclockwise to change the orientation of the holding projection 39 from the outside inward, the gear portion 27 is rotated 180 ° and the right movable pin 20 is turned moves the gear portion 25 in the pin hole 19 so as to engage the pin hole 19 and the right engagement hole 17 . As a result, the right front part 27 of the pliers can be positively connected to the left handle lever 3 via the right actuating lever 10 . In the meantime, if the right pliers front part 27 is rotated 180 ° clockwise or counterclockwise to change the orientation of the holding projection 39 from the inside out, the gear section 25 which is positively connected to the right pliers front part 27 is likewise rotated through 180 °, and the right movable pin 20 is moved by the gear portion 25 in the pin hole 19 so as to be engaged with the pin hole 19 and the right engagement hole 15 . Thus, the right pliers front part 27 can be positively connected to the right handle lever 2 via the right actuating lever 10 .

The connection between the left pliers front part 35 and the left movable pin 22 is designed in the same way: If the left pliers front part 35 is rotated clockwise or counterclockwise by 180 ° in order to rotate the alignment of the retaining ring holding part 40 inwards, it becomes form-fitting gear portion 33 connected to the left pliers front part 35 is rotated in the same manner by 180 °, and the left movable pin 22 is moved by the gear portion 31 in the pin hole 21 to engage the pin hole 21 and the left engagement hole 16 . Thus, the left pliers front part 35 can be positively connected (coupled) to the right grip lever 2 via the left actuation lever 11 . In the meantime, the left pliers front part 35 can also be rotated clockwise or counterclockwise by 180 ° in order to change the orientation of the retaining ring holding part 40 from inwards to outwards, the gear section 33 , which is positively connected to the left pliers front part 35 , likewise is rotated by 180 ° and the left movable pin 22 is moved in the pin hole 21 over the gear portion 33 to engage the pin hole 21 and the left engagement hole 18 . Thus, the left pliers front part 35 can be positively connected to the right handle lever 3 by means of the right operating lever 11 .

A spherical lock 42 engages with an annular groove 41 of the right rotary shaft 24 without the rotation of the rotary shaft 24 being hindered. This lock 42 is moved into the guide hole 23 by a threaded bore 43 of the right actuating lever 10 . A screw 44 screwed into the threaded bore 43 engages with the annular groove 41 and is held therein. The lock 42 prevents the right rotary shaft 24 from slipping out of the guide hole 23 and places the right rotary shaft 24 in the guide hole 23 so that the gear portion 25 and the teeth 26 of the right movable pin 20 remain in engagement with each other.

Likewise, a spherical lock 46 engages with an annular groove 45 of the left rotary shaft 32 without the rotation of the rotary shaft 32 being hindered. This lock 46 is moved through a threaded bore 47 of the left actuating lever 11 into the guide hole 31 and held by a screw 48 screwed into the threaded bore 47 and is in engagement with the annular groove 45 and held therein. The lock 42 prevents the left rotary shaft 32 from slipping out of the guide hole 31 and places the left rotary shaft 32 in the guide hole 31 such that the gear portion 33 and the teeth 34 of the left movable pin 22 remain meshed with each other.

A rolling element 51 is enclosed in a locking recess 49 of a side surface of the right movable pin 20 within a locking slot 50 along the longitudinal axis of the surface of the pin hole 19 . The rolling element 51 is held in the locking recess 49 , in which position the rolling element 51 can roll along the locking slot 50 when the right movable pin 20 is moved and rolls until it is flush with the hole edge of the right engagement hole 15 or 17 in System comes so that the movable pin 20 abuts against it and thus it is also prevented that the movable pin 20 slips out, the movement of the right movable pin 20 in the axial direction is not disturbed. At the same time, the meshing engagement of the toothed section 26 with respect to the gear section 25 is also maintained.

In the same way, a rolling element 54 is enclosed in a locking recess 52 in a side surface of the left movable pin 22 within a locking slot 53 along the longitudinal axis of the surface of the pin hole 21 . The rolling element 54 is held in the locking recess 52 such that the rolling element 54 can roll along the locking slot 53 when the left movable pin 22 moves and the element 54 rolls off until it is aligned with the hole edge of the left engagement hole 16 or 18th comes in plant. Thus, the left movable pin 22 is stopped and prevented from slipping out without interfering with the movement of the left movable pin 22 in the axial direction. However, the meshing engagement of the toothed section 34 with the gear section 33 is also maintained at the same time.

On the front edge of the right operating lever 10 , there are a pair of right and left vertical surfaces (surfaces to be engaged) 56 , 56 which engage with right and left side surfaces (gripping surfaces) 55 , 55 . The gripping surfaces 55 , 55 themselves are created on the base side of the shaft section 28 of the two front parts 27 , 35 of the tong in order to limit the rotation of the front parts 27 and 35, respectively. The connection structure between the engaging groove 29 and the engaging projection 30 is determined by a first fixed position in which the gripping surfaces 55 , 55 engage the vertical surfaces 56 , 56 to control the rotation of the right front part 27 of the pliers and by a second determined position in which the gripping surfaces 55 , 55 are disengaged from the vertical surfaces 56 , 56 to allow free rotation of the right front jaw part 27 . The right pliers front part 27 , as shown in FIG. 14, is in the first fixed position.

The shaft section 28 in the right front part 27 of the pliers has an engagement recess 57 (first recess section) on the surface, so that a dome-like lock 58 on the side of the right actuation lever 10 is pressed by a leaf spring 59 fixed by means of a screw 47 in order to engage the engagement recess 57 to snap when the right front pincer 27 is in the first fixed position so that the former cannot get out until the right front pincer 27 is deliberately removed. In addition, the connection between the front jaw part 27 and the rotating shaft 24 is maintained.

The engaging recesses 57 are provided at a position in the direction of curvature of the holding projection 39 and at a position of the relative position in the surface of the shaft portion 28 , so that the retaining ring holding part 39 locks in an outward as well as in an inward direction when the Lock 28 engages with one of the engagement recesses 57 .

The shaft portion 28 in the right pliers front part 27 is formed in the surface with an annular groove (a second recess) 60 , so that the lock 58 is pressed by a leaf spring 59 to snap into the annular groove 60 when the right pliers front part 27 in the second specified position. In addition, the pliers front part 27 is rotated by 180 ° in the second fixed position, whereby the retaining ring holding part 39 can be changed outwards and inwards and the pliers front part 27 does not slip out until the right pliers front part 27 is deliberately removed. Here, the connection between the front part of the tongs 27 and the rotary shaft 24 is maintained. The annular groove 60 is formed in an area with recess portions 61 in the direction of curvature of the holding projection 39 , so that the retaining ring holding part 39 locks in an outward position as well as in an inward position when the lock 58 with one of the recess portions 61 snaps in.

Similarly, a pair of right and left vertical surfaces (surfaces to be engaged) 63 , 63 are provided on the front edge of the left operating lever 11 , which engage a pair of right and left side surfaces (gripping surfaces) 62 , 62 . The flank surfaces are formed in the surface in a base side of the left tong part 35 close to the shaft section 36 in order to control the rotation of the left tong part 35 . The connection between the engagement groove 37 and the retaining ring holding part 38 is determined by a first fixed position in which the flank surfaces 62 , 62 engage the vertical surfaces 63 , 63 to control the rotation of the left pliers front part 35 . Furthermore, there is also a second fixed position in which the flank surfaces 62 , 62 are disengaged from the vertical surfaces 63 , 63 so that the front part of the pliers 35 can rotate freely. The left pliers front part 35 , as shown in FIG. 14, is in the second fixed position.

The shaft portion 36 in the left pliers front part 35 is formed on the surface with an engagement recess (a first recess portion) 64 so that a ball-like lock 65 on the side of the right operating lever 10 is pressed by a leaf spring 66 which is held by a screw 48 to snap into engagement recess 64 when the left front pincer 35 is in the first fixed position so that the former cannot get out until the left pincer front 35 is deliberately removed. The connection relationship between the front part of the pliers 35 and the rotary shaft 32 is maintained. The engaging recesses 64 are formed at a position in the direction of curvature of the snap ring holding part 40 in a relative position of the surface of the shaft portion 36 , so that the locking ring holding part 40 blocks or locks in an outward as well as in an inward position when the Lock 65 snaps with one of the engagement recesses 64 .

The shaft portion 36 in the left pliers front part 35 is formed on the surface with an annular groove (a second recess portion) 67 so that the lock 65 is pressed by a leaf spring 66 to snap into the annular groove 67 when the left pliers front part 35 is in the second specified position. The forceps front 35 is rotated 180 ° in the second fixed position, whereby the snap ring holding part 40 can be directed inwards or outwards and the former cannot slide out until the forceps front 35 is deliberately removed when moving from the first fixed position to the second set position. The connection between the front part of the pliers 35 and the rotary shaft 32 is maintained. The annular groove 67 is formed in a portion in the direction of curvature of the holding projection 40 with recess portions 68 and in such a relative position that the retaining ring holding part 40 locks or locks in an outward and inward position when the lock 65 is in one the recess sections 68 snaps.

Both snap ring holding parts 39 , 40 are formed with fine grooves 69 , 70 to form a slide-out lock so as to prevent the locking ring holding parts 39 , 40 from disengaging from the holding holes of a locking ring when the latter is attached or removed.

Furthermore, a section between the flank surfaces 55 , 62 on the base side of both tongs front parts 27 , 35 on the circumferential surface is provided with knurls 71 , 72 . Accordingly, the rotation of the two front parts 27 , 35 of the pliers by 180 ° can be carried out properly even with oily hands.

Alternatively, the locks 58 , 65 can be pretensioned by coil springs 73 , 74 , as shown in FIG. 15, so that they snap into the engagement recesses 57 , 64 and the ring grooves 60 , 67 depending on the position.

Fig. 17 (c) shows a position in which the pliers 1 is set on a shaft lock ring. Both retaining ring holding parts 39 , 40 of the two front parts 27 , 35 of the pliers are turned outwards. The right movable pin 20 , which is positively connected to the right pliers front part 27 , is in engagement with the pin hole 19 in the right actuating lever 10 . The right engaging hole 15 of the right handle lever 2 and the right pliers front part 27 and the right handle lever 2 are positively connected via the right operating lever 10 . The left movable pin 22 , which is integrally connected to the left pliers front part 35 , engages with the pin hole 21 in the left operating lever 11 . The left engagement hole 18 of the left handle lever 3 and the left pliers front part 35 and the left handle lever 3 are positively connected via the left operating lever 11 . With this position of the elements, the two handle levers 2 , 3 can then be gripped. Both circlip holding parts 39 , 40 are inserted into a hole 201 in the shaft circlip 200 . Both ends of the locking ring are brought apart by pressing the handle levers 2 , 3 together , and the locking ring can be inserted into or removed from a shaft groove.

Fig. 17 (b) shows a position in which the pliers 1 is set for receiving a circlip for a hole. Both retaining ring holding parts 39 , 40 of the two front parts 27 , 35 of the pliers are turned inwards. The right movable pin 20 , which is positively connected to the right pliers front part 27 , is in engagement with the pin hole 19 in the right actuating lever 10 . The right engaging hole 17 of the left handle lever 3 and the right pliers front part 27 and the left handle lever 3 are positively connected via the right operating lever 10 . The left movable pin 22 , which is positively connected to the left pliers front part 35 , is in engagement with the pin hole 21 in the left actuation lever 11 and with the left engagement hole 16 of the right handle lever 2 . The left pliers front part 35 and the right handle lever 2 are positively connected via the left operating lever 11 . In this position of the elements, the two handle levers 2 , 3 are gripped and both retaining ring holding parts 39 , 40 can be inserted into openings 411 of a retaining ring 410 for a bore. Both ends of the locking ring can then be brought together by actuating the handle levers 2 , 3 , so that removal or insertion into a groove in a bore is possible.

Fig. 17 (a) shows a position in which the pliers 1 can be rotated into a for receiving a shaft or a bore securing ring. The two handle levers 2 , 3 are pressed together. The pin hole 19 and the pin hole 21 are vertically aligned with the right engagement holes 15 , 17 of the two handle levers 2 , 3 and with the left engagement holes 16 , 18 of the left and right handle levers 2 , 3, respectively, by means of the two movable pins 20 , 22 to move the two tongs front parts 27 , 35 .

Then the two pliers front parts 27 , 35 located in the first fixed position are pressed towards the guide side in order to transfer them to the second position. Both pliers front parts 27 , 35 are rotated into the second position in order to assume a position in which they can be used for receiving a circlip for a bore, ie the position in which the circlip holding parts 39 , 40 point towards one another or respectively inwards are aligned. Then the engagement between the two pliers front parts 27 , 35 and the handle levers 2 , 3 can be automatically determined via the two actuating levers 10 , 11 . The right and left pliers front parts 27 , 35 are rotated to the second position to assume a position in which they are suitable for receiving a shaft locking ring, ie a position in which the locking ring holding parts 39 , 40 are directed outwards. Then the connection between the two pliers front parts 27 , 35 and the handle levers 2 , 3 via the two actuating levers 11 is also automatically determined for use in a shaft retaining ring.

If the two pliers front parts 27 , 35 are pulled towards the base side after the desired position has been determined, they can automatically return to the first position. The flank surfaces 55 , 55 , 62 , 62 engage the vertical surfaces 56 , 56 , 63 , 63 , thereby controlling the rotation of both front jaw parts 27 , 35 . Both retaining ring holding parts 39 , 40 are deformed by a predetermined angle or the two front parts of the pliers, in which the retaining ring holding parts extend at right angles, are acted upon by a moment of force such that they rotate about the longitudinal axis of the front parts 27 , 35 of the pliers . Even in this case, it is possible to control the rotation of the pliers front parts 27 , 35 to prevent the locking ring holding parts from changing position. If the forceps front parts 27 , 35 are rotated into the second position, they can be changed freely, depending on the desired application.

The two pliers front parts 37 , 35 are formed from a memory alloy or a so-called shape memory alloy.

More specifically, the two tongs front parts 27 , 35 are molded or cast using methods known in the art. Among these known processes is a process that includes: sufficient machining and pre-hardening of a Ni-Ti based alloy, processing of this alloy into a mold for right and left pliers front parts 27 , 35 and exposure of this alloy for a few minutes to a few hours Temperature from 400 ° C to 500 ° C while fixed in the present form. Also included is a process that includes: very rapidly cooling a Ni-Ti based alloy after being exposed to a temperature of 800 ° C for a while, or, as before, processing into a shape of right and left pliers front parts 27 , 35 and hold at a relatively low temperature of 200 ° C to 300 ° C. As a result, the two pliers front parts 27 , 35 are subjected to shape memory processing, in such a way that the retaining ring holding parts 39 , 40 are somewhat curved with respect to the longitudinal axis. Even when the circlip retaining parts 39 , 40 are bent repeatedly, they return to their initial shape, which is somewhat curved with respect to the longitudinal axis when the circlip retaining parts 39 , 40 are placed in hot water at a temperature of approximately 60 ° C. to 90 ° C immersed and warmed.

Accordingly, the snap ring holding parts 39 , 40 are suitably deformed by predetermined tools such as a jig, some kind of key, or the like. According to these tools, they can be appropriately aligned with different attachment and removal positions and adapted to the different circlip sizes without the front parts of the pliers 27 , 35 having to be replaced. This is because the front parts of the pliers 27 , 35 can be restored to their initial shape by an extremely simple operation, for example by immersing the front parts of the pliers 27 , 35 in hot water after use.

Fig. 6 shows an embodiment of a teaching 300th This gauge 300 is molded from a selected hard material into a box-like shape. A hole 301 is formed in a side surface thereof. The front part of the respective pliers front part 27 or 35 can be inserted into this hole 301 . The front of the tongs front parts 27 , 35 is inserted into the hole 301 ( Fig. 6A). In this position, either the pliers 1 or the gauge 300 are held while the respective other part is bent in a predetermined direction, whereby the front parts of the pliers 27 , 35 inserted in the hole 301 are deformed at a predetermined angle ( FIG. 6B) can be. The direction of deformation can be selected as desired, for example inwards, outwards or in the transverse direction of the direction of curvature of the retaining ring holding parts 39 , 40 in the front parts 27 , 35 of the pliers. After an attachment or removal process of differently sized circlips and different positions for attaching or detaching these circlips, the pliers front parts 27 , 35 can resume their initial shape through the very simple process, such as immersion in hot water ( FIG. 6C).

The setting mechanism is described below. The adjustment mechanism shown in Figs. 1 and 2 includes a right engagement portion 75 which is provided on the right handle lever 2 . It also includes a left engagement portion 76 formed on the left handle lever 3 .

The right engaging portion 75 includes a projection that protrudes on the back near a support portion 2 a at the front of the right handle lever 2 (that is the surface opposite the left handle lever 3 ). In the illustrated embodiment, the projection on the right handle lever 2 is integrally formed.

The left engagement portion 76 includes an adjustment lever 77 . whose base section 77 b is attached to the left handle lever 3 and is supported in the manner of a cantilever, so that a front section 77 a extends outward toward the right handle lever 2 . Also included is a threaded rod 79 which is attached to the actuating lever 77 in such a way that it lies in a slot 78 which is formed in a central portion of the actuating lever 77 . Furthermore, a knurled nut is placed on the threaded rod 79 , and can be moved in the longitudinal direction of the adjusting lever 77 by screwing back and forth. One half of the knurled nut 80 is placed in the slot 78 . The other half of this can be placed in engagement and engagement with an inner edge 2 b of the right handle lever 2 . As a result, the two handle levers 2 , 3 are then pulled together. The knurled nut 80 moved into a suitable position comes into contact with the inner edge 2 b of the right handle lever 2 in order to suitably set a closing angle of both handle levers 2 , 3 . A plurality of projections 81 a, 81 b and 81c, which are to the right engaging portion 75 in contact with and in engagement face in the longitudinal direction of the actuating lever 77th The shape of the protrusions 81 a to 81 c and that of the right engagement section 75 is, as is very well shown in FIG. 2, wedge-shaped or triangular in cross-section.

The light engagement section 75 can drive on the protrusions 81 a to 81 c in the closing direction of the two handle levers 2 , 3 , but the right engagement section 75 engages with the projection 81 a to 81 c in the opening direction of both handle levers 2 , 3 control their opening process, whereby the opening angle of both handle levers 2 , 3 is suitably controlled by the bias of the springs 9 .

The adjusting lever 77 is formed so that it has an elasticity sufficient that it can be curved in a direction away from the right handle lever 2 by pressing the front end portion 77 a, thereby thereby engaging between the right engaging portion 75 and each of the projections 81 a to solve 81 c.

In the present embodiment, in view of the different sizes (these sizes range from small to medium or large size) of circlips for a shaft as well as circlips for a bore, the aforementioned projections 81 a, 81 b and 81 c are so created that an opening angle between the two handle levers 2 , 3 can be set in three stages according to the required size. In the case where the angle is set for a hole, the projection 81 a corresponds to a small size, the projection 81 c to a medium size and the projection 81 b to an intermediate size. In the case where the angle is set for a shaft, the projection 81 a corresponds to a medium size, the projection 81 c to a small size and the projection 81 b to an intermediate size.

Furthermore, a closing angle of both handle levers 2 , 3 can be set in any stage. However, suitable three positions of the threaded rod 79 are preferably marked so that the closing angle can be set in three stages in accordance with the opening angle.

The setting of the opening angle and the closing angle of the two handle levers 2 , 3 by means of the adjusting mechanism will now be described for the case in which a locking ring for a bore is to be attached or removed.

In Fig. 1 the pliers 1 is set for attaching or detaching a retaining ring for a bore. So that the right engagement portion 75 is not in contact with any of the projections 81 a to 81 c. Because of this, the pretension of the spring 9 pushes both handle levers 2 , 3 the farthest apart. In other words, the two retaining ring holding parts 39 , 40 are the most distant from each other. Since in this position the knurled nut 80 is in the position furthest away from the right handle lever 2, the handle levers 2 , 3 come to each other the most when they are pressed together. In other words: the two retaining ring holding parts 39 , 40 can get extremely close to one another. That is to say, this is an unadjusted state in which the two retaining ring holding parts 39 , 40 can be moved from a most distant position to a very close closing position, so in this position of the adjusting mechanism the retaining ring holding parts 39 , 40 are on the one hand the most distant from each other and on the other hand also the closest to each other.

Fig. 3 shows a setting for a medium-sized circlip for a bore which has a relatively large diameter.

That is, the two handle levers 2, 3 are slightly compressed so as to cause that the right engaging portion 75 between the projections 81 c and 81 b to lie comes, so that the right engaging portion 75 c on the projection 81 mitfährt from the non-set state .

In this position, the opening angle of both handle levers is set due to the compressive force of the spring 9 so that the right engaging portion 75 comes into engagement and engagement with the projection 81 c, whereby the left and right retaining ring holding parts 39 , 40 are spaced apart by a distance S1 are, but it allows that they can be used n holes at both ends of a medium-sized circlip for a hole ( Fig. 3a).

The knurled nut 80 is actuated and positioned in a suitable position. Then when both handle levers 2 , 3 are pressed together, the inner edge 2 b of the right handle lever 2 comes into contact with the knurled nut 80 , whereby the closing angle of both handle levers is determined such that a distance S2 of the two retaining ring holding parts 39 , 40 is added it is suitable that both ends of a medium-sized circlip for a hole are pressed towards each other in a suitable manner. So it is possible to remove or insert such a circlip into a hole ( Fig. 3a).

Accordingly, the pliers 1 are spaced between a position in which the two snap ring holding parts 39 , 40 are suitably spaced for insertion into holes of a medium-sized snap ring for a bore (S1), and a position in which they come together so far that the two Ends of the snap ring are compressed by an appropriate amount, as shown by arrow θ1 in FIG. 1.

FIG. 4 shows a set position for the application in which a small-sized bore retaining ring which has a relatively small diameter has been inserted.

Here, both handle levers 2 , 3 are pushed together, so that the right engagement section 75 rides on the projections 81 a to 81 c to cause the right engagement section 75 to be positioned on the inside of the projection 81 a. In this position, the opening angle of both handle levers is determined by the pressure force of the spring 9 so that the right engaging portion 75 comes into engagement and engagement with the projection 81 a, whereby the two retaining ring holding parts 39 , 40 are spaced apart at a distance S3 it is just right that a small circlip for a hole can be accommodated in both holes ( Fig. 4a).

The knurled nut 80 is actuated and positioned at a suitable location. If both handle levers 2 , 3 are then pressed together, the inner edge 2 b of the right handle lever 2 comes into contact and engagement with the knurled nut 80 , as a result of which the closing angle of both handle levers is determined such that a distance S4 between the two retaining ring holding parts 39 , 40 is created which is suitable for compressing a small circlip for a hole at both ends by a suitable amount ( Fig. 4b).

Accordingly, the pliers 1 can be actuated between a position in which the two retaining ring holding parts 39 , 40 are spaced apart by a distance S3, which is suitable for receiving a small retaining ring for a bore in its holes, and a position, in which the locking ring holding parts 39 , 40 come together except for a dimension 54 in which the two ends of the locking ring are pressed together by a suitable path length, as shown by the arrow θ2 in FIG. 1.

Fig. 5 shows a setting for a circlip for a bore, which has an intermediate size, ie a size that is between a small and a medium size.

Here both handle levers 2 , 3 are pressed together so that the right engagement section 75 is guided over the projections 81 c to 81 b, so that the right engagement section 75 is positioned between the projections 81 a and 81 b. In this position, the two handle levers are fixed in a position due to the urging force of the spring 9, in which the right engaging portion 75 b with the boss 81 comes into abutment, whereby the two backup ring holding part 39, 40 have a spacing S5 therebetween which it is suitable that the locking ring holding parts 39 , 40 can be inserted into holes at both ends of an intermediate size locking ring for a bore ( FIG. 5a).

The knurled nut 80 is then actuated and positioned at an appropriate location. If both handle levers 2 , 3 are then pressed together, the inner edge 2 b of the right handle lever 2 comes into contact and engagement with the knurled nut 80 , whereby the closing angle of both handle levers is determined so that a distance S6 between the two retaining ring holding parts 39 , 40th is present, in which both ends of the intermediate ring having a locking ring for a bore are moved towards each other by a suitable distance ( FIG. 5b).

Accordingly, the pliers 1 are operated between a position in which the two retaining ring holding parts 39 , 40 are spaced S5 between them, which ensures that an intermediate size retaining ring can be received for drilling both holes, and a position, in which the locking ring holding parts can be moved towards each other up to a distance S6, so that both ends of the locking ring can be moved towards each other by a suitable path length, as shown by arrow θ3 in FIG. 1.

In a case where the setting state is released or changed with respect to the opening angle, the front end portion 77 a of the operating lever 77 is pressed in the direction of the arrow 82 , as shown in FIG. 2, and elastically deformed in the direction away from the right handle lever 2 , whereby the engagement between the right engagement portion 75 and the projections 81 a to 81 c is released. In the event that the setting state with respect to the closing angle is released or changed, the knurled nut 80 can be moved in a predetermined direction.

Furthermore, with pliers 1, it is also possible to set the settings on the setting mechanism as previously explained for a circlip for a bore, also for circlips for a shaft. So it is also possible to make the setting for a shaft locking ring that is small in size with a relatively small diameter. It is also possible to make a setting for a shaft locking ring which is of a medium size and has a relatively large diameter, and also to make a setting for a shaft locking ring which has an intermediate size between the small and the medium size. The settings must then be made in accordance with FIGS. 3, 4 and 5. In the previously described embodiment of the adjustment mechanism, projections 81 a to 81 c are provided at three locations, as a result of which the opening angle of both handle levers 2 , 3 can be adjusted in three stages. However, it should be emphasized that the number of protrusions is not limited to the aforementioned number, but only one protrusion or two is sufficient and may be preferred. The higher the number of protrusions, the finer the setting.

In the above embodiment of the present invention, the opening angle of both handle levers 2 , 3 can be set in specific steps, whereas the closing angle thereof can be set continuously. However, it should be emphasized that the present invention is not limited to this, as is also included in claim 2, but different configurations thereof are possible. It is thus possible to make the opening angle infinitely adjustable and to set the closing angle in specific steps, ie vice versa to the present embodiment. Furthermore, it is also possible to configure the opening and closing angles to be adjustable in specific steps, or to configure both, ie the opening and closing angles, to be infinitely adjustable.

For example, although it is not shown, instead of providing the right engagement section 75 and the projections 81 a to 81 c, it would be possible to extend the threaded rod 79 to such an extent that it extends outward beyond the right handle lever 2 and that with the outer edge 2 c of the right handle lever 2 in contact and engagement knurled nut is rotated into the outer portion. Thus, the knurled nut 80 is placed in a suitable way, that is, both the opening and the closing angle can be infinitely adjusted in 13973 00070 552 001000280000000200012000285911386200040 0002019725597 00004 13854.

An embodiment of a pair of pliers 1 for attaching or detaching a snap ring is described below with reference to FIGS. 7 to 10.

In this further embodiment, right and left pliers front parts 83 , 84 are provided on the front sides with snap ring holding parts 85 , 86 for a snap ring. The front jaw parts 83 , 84 are rotatably and removably attached to the two actuating levers 10 , 11 . Both pliers front parts 83 , 84 can be used for the pliers front parts 27 , 35 and can be exchanged for these in order to be able to attach or remove a snap ring 400 on a shaft 500 .

The two pliers front parts 83 , 84 are similar to the above-explained pliers front parts 27 , 35 , except for the snap ring holding parts 85 , 86 on the front sides.

Accordingly, only the first will be explained Embodiment differing components below described.

The snap ring holding part 85 , which is provided on the front side of the right pliers front part 83 , is in the form of a narrow flat plate that includes an inner surface side that is slightly curved. This curved surface 87 is curved as seen in the width direction. Furthermore, the flat plate comprises an outer surface side which is flat, that is to say has a flat surface 88 . The right pliers front part 83 can be rotated by 180 ° in the second position in order to align the curved surface 87 of the holding projection 85 inwards or can be rotated so that the curved surface 87 points outwards. Similarly, the snap ring holding part 86 , which is formed on the front side of the left pliers front part 84 , is shaped as a narrow flat plate which has an inner surface side in the form of an arc surface 89 , which in turn is curved in the width direction, and which has an outer surface side in the form of a flat surface 90 . The left pliers front part 84 , like the right pliers front part, can be rotated through 180 ° in the second position in order to ensure that the curved surface 89 of the snap ring holding part 86 points inwards or outwards. The curved surfaces 87 , 89 and the flat surfaces 88 , 90 can be formed with fine grooves (not shown) that prevent slipping away.

The connection between the two tongs front parts 83 , 84 and the two movable pins 20 , 22 is such that both tongs front parts 83 , 84 are rotated in the second position so that the two curved surfaces 87 , 89 face each other and point inwards. In this position, the coupling between the two forceps front parts 83 , 84 and the handle levers 2 , 3 is automatically set to the operating position for a shaft via the right actuating lever 10 and the left actuating lever 11 (see FIG. 7). Furthermore, the forceps front parts 83 , 84 can be rotated in the second position, so that the two curved surfaces 88 , 90 point away from each other, ie outwards, so that a position is achieved in which the coupling between the two forceps front parts 83 , 84 and the handle levers 2 , 3 via the right operating lever 10 and the left operating lever 11 is automatically set in the drilling operating position (see FIG. 9).

In the state shown in FIG. 8 a, the left snap ring holding part 86 is brought into contact with the shaft 500 , so that the curved surface 89 lies against the outer peripheral surface of the shaft 500 . The right snap ring holding member 85 is engaged with the snap ring 400 into contact so that the arc surface 87 at the outer circumferential surface of the snap ring 400 which is applied to the shaft 500, is applied. If both handle levers 2 , 3 are now pressed together, the snap ring holding parts 85 , 86 are moved towards one another and the snap ring 400 is pressed onto the shaft 500 , as shown in FIG. 8b.

In the other case, as shown in FIG. 10a, ie the shaft operating position, the left snap ring holding part 86 is placed in contact with the shaft 500 , so that the curved surface 89 lies along the outer peripheral surface of the shaft 500 . The right one in the snap ring holding part 85 is placed on the snap ring 400 , so that the curved surface 87 bears against the inner peripheral surface of the snap ring 400 seated on the shaft 500 . If both handle levers 2 , 3 are now pressed together, the snap ring holding parts 85 , 86 are guided away from one another and the snap ring 400 is lifted off the shaft 500 , as shown in FIG. 10b.

As an alternative to this, as shown in FIG. 10c, a suitable section of the snap ring 400 seated on the shaft 500 is clamped between the two flat surfaces 88 , 90 which are aligned with one another. If, with the clamped snap ring 400, the snap ring 400 is then pulled outwards, the snap ring 400 can be completely removed from the shaft 500 .

The forceps front parts 83 , 84 can in turn advantageously be formed from a shape memory alloy like the forceps front parts 27 35 explained at the beginning. In this case, the snap ring holding parts 85 , 86 are suitably deformed by suitable tools, such as a gauge, a type of key, device or the like, as a result of which they can be adapted to different attachment or removal positions and different sizes of snap rings, without the front jaw parts 83 , 84 having to be replaced in each case. After use, the forceps front parts 83 , 84 can be returned to their initial shape by a very simple treatment, such as immersion in hot water.

It should be emphasized again that the present invention not to the previously described embodiments is limited. Various other embodiments can at least within the range defined by claims 1 to 6 circumscribed protection area designed in various ways will.

In a modified embodiment, parts of the internal structure of the actuating levers 10 , 11 - see Fig. 14 - can be suitably formed as disclosed in the devices previously proposed by the present applicant (see Japanese Patent Examined Publication No. Hei 7- 49186, Japanese Unexamined Patent Publication No. Hei 7-112778, etc.).

The pliers or, in general, the attachment and removal tool according to the present invention, as described above,  is designed, has the present advantages and effects on.

In addition to the benefits of switching between a shaft operating position in which the two Circlip retaining parts are moved away from each other, and a hole position in which the two circlip Holding parts are moved towards each other, it is opposite the earlier embodiment possible that the pliers on different mounting or removal positions and different sizes of circlips can be adapted can be replaced without changing the front parts of the pliers have to. Due to the geometrically achievable effects in With regard to various aspects, such as Practicability, handling, multiple functions, usability, How it works, etc., very beneficial effects that can be achieved could not be reached with conventional devices.

In addition to the advantages of switching between a shaft operating position and a bore Operating position, as previously explained, can in another embodiment, as they is circumscribed in claim 2, for example Circlip retaining parts within a suitable range according to the sizes of the circlips. This eliminates the need for the two handle levers to squeeze forcefully so that they only then in the holes of the snap rings or appropriate Distances are insertable. It can be this distance be preset according to the size of the Circlips. It is also possible that the Circlip not extended or more than necessary is squeezed. Because of this, again same advantages in terms of handling, Practicability, mode of action, etc., as before have been described, achievable.  

In one embodiment, in which the embodiment according to claim 1, wherein the two Pliers front parts consist of a shape memory alloy, the execution according to claim 2 is added, can due to the geometric function the previously mentioned Effects are even better.

The achievable by the training in claim 2 Effects can be achieved through a relatively simple construction be achieved advantageously and the setting of Adjustment device is possible in a very simple manner. Of the basic section of the actuating or Flanged control lever with respect to the left handle lever or be removed therefrom and the left engaging portion can be flanged or removed. Because of that the use is simplified without an adjustment by means of the adjustment device is necessary. In addition, the right engagement section formed in front of the right handle lever or the right engaging portion is through Fasteners, such as a screw Connector or the like attached. The latter can this also applies to conventional objects that are not compatible with the adjustment mechanism are also achieved will.

In the objects described in claims 1 to 3 may have the aforementioned effects and advantages due to the geometric functional advantage can be achieved very well, these advantages even with the only on the Conversion mechanism limited equipment of the pliers, such as it is initially explained in the present application, be achieved. Both the circlip Holding parts in the two front parts of the pliers as well left and right handle levers can be swapped freely and for different applications can be set, for example for the application of attaching or removing one Circlip for one hole, d. H. the so-called  Bore operating position, or an application for mounting or removing a shaft retaining ring, the so-called Shaft operating position. Both applications are possible by performing only one activity, namely that Turn the two front parts of the pliers.

A very advantageous embodiment according to claim 4 also has the advantage that the rotation of the Pliers front parts can be controlled to a Positional deviation of the circlip retaining parts prevent. This advantage is in addition to the advantage too see that the position change for a wave or a Bore operating position only by turning the both front pliers can be made freely, even in the case where the front of the pliers with the circlip Holding parts are provided on which a torque is exerted becomes in the direction of rotation about the longitudinal axis. In the advantageous embodiment according to claim 5, the one includes two-stage barrier construction, in which the Pliers front parts in a first and a second Locking position can be blocked, the change between the first position and the second position very much be carried out easily and simply and the shaft sections the front of the pliers are blocked in the pilot hole to maintain the common rotation with the turning shafts. But this is the exchange or removal of Front parts of the pliers do not necessarily have to be replaced prevented when pulling with sufficient force.

By exchanging the front parts of the pliers, the Subject of claim 6 to the front parts of the pliers Attaching or removing a snap ring can be used. So there are even more multifunctional properties for contains various requirements.

Claims (6)

1. Pliers, comprising a pair of right and left handle levers ( 2 , 3 ), a support shaft ( 6 ) for rotatably holding overlapping support sections ( 2 a, 3 a) of the front sections of the two handle levers ( 2 , 3 ), each ( 9 ) for biasing sections of the two handle levers ( 2 , 3 ) in an open state, a pair of right and left actuating levers ( 10 , 11 ), in which intermediate sections of the basic lever sections ( 10 a, 11 a), which are between the support sections ( 2 a, 3 a) are present, are rotatably held in such a way that they are aligned coaxially with the holding axis ( 6 ), a pair of right and left pliers front parts ( 27 , 35 ) which are in the guide sides of both actuating levers ( 10 , 11 ) are used, and in which each has a retaining ring holding part ( 39 , 40 ) on its front side which is somewhat curved with respect to the longitudinal direction (longitudinal axis), a switching device for switching between one Shaft operating position in which the two retaining ring holding parts ( 39 , 40 ) are moved away from one another by compressing the two handle levers ( 2 , 3 ), and a bore operating position in which the retaining ring holding parts ( 39 , 40 ) are actuated the handle lever ( 2 , 3 ) can be moved towards one another, the two front parts of the pliers ( 27 , 35 ) being formed from a shape memory alloy. 2. Pliers, comprising a pair of right and left handle levers ( 2 , 3 ), a support shaft ( 6 ) for rotatably holding overlapping support sections ( 2 a, 3 a) of the front sections of the two handle levers ( 2 , 3 ), a spring ( 9 ) for biasing sections of the two handle levers ( 2 , 3 ) in an open state, a pair of right and left actuating levers ( 10 , 11 ), in which intermediate sections of the basic lever sections ( 10 a, 11 a), which are between the support sections ( 2 a, 3 a) are present, are rotatably held in such a way that they are aligned coaxially with the holding axis ( 6 ), a pair of right and left pliers front parts ( 27 , 35 ) which are in the guide sides of both actuating levers ( 10 , 11 ) are used, and in which each has a retaining ring holding part ( 39 , 40 ) on its front side which is somewhat curved with respect to the longitudinal direction (longitudinal axis), a switching device for switching between one Shaft operating position in which the two retaining ring holding parts ( 39 , 40 ) are moved away from one another by compressing the two handle levers ( 2 , 3 ), and a bore operating position in which the retaining ring holding parts ( 39 , 40 ) are actuated the handle lever ( 2 , 3 ) can be moved towards one another, the pliers having an adjusting device with which an opening angle between the two handle levers ( 2 , 3 ) can be set with prestress by the spring ( 9 ) and a closing angle between them, ie when the two handle levers ( 2 , 3 ) are pressed together. 3. Pliers according to claim 2, wherein the adjusting means comprises a right engaging portion ( 75 ) provided on the right handle lever ( 2 ) and a left engaging portion ( 76 ) provided on the left handle lever ( 3 ), the Left engagement section 76 comprises an operating lever ( 77 ) which is mounted in the manner of a boom on a base section ( 77 b), which in turn is attached to the left handle lever ( 3 ) so that the front end section ( 77 a) over the right handle lever ( 2 ) protrudes, a threaded rod ( 79 ) being attached in the intermediate section of the operating lever ( 77 ) and an element ( 80 ) which can be moved by rotating on the threaded rod ( 79 ) being present and which engages and engages with the inner edge ( 2 b) of the right one handle lever (2) can be brought to the closing angle of the two grip levers (2, 3) to be adjusted, and wherein a number of protrusions (81 a, 81 b, 81 c) is present in the predetermined Abs conditions in the longitudinal direction of the operating lever ( 77 ) are designed to come into contact with the right engagement section ( 75 ) so that the opening angle between the two handle levers ( 2 , 3 ) is adjustable. 4. Pliers, comprising a pair of right and left handle levers ( 2 , 3 ), a support shaft ( 6 ) for rotatably holding overlapping support sections ( 2 a, 3 a) of the front sections of the two handle levers ( 2 , 3 ), a spring ( 9 ) for biasing sections of the two handle levers ( 2 , 3 ) in an open state, a pair of right and left actuating levers ( 10 , 11 ), in which intermediate sections of the basic lever sections ( 10 a, 11 a), which are between the support sections ( 2 a, 3 a) are present, are rotatably held in such a way that they are aligned coaxially with the holding axis ( 6 ), a pair of right and left pliers front parts ( 27 , 35 ) which are in the guide sides of both actuating levers ( 10 , 11 ) are used, and in which each has a retaining ring holding part ( 39 , 40 ) on its front side which is somewhat curved with respect to the longitudinal direction (longitudinal axis), a switching device for switching between one Shaft operating position in which the two retaining ring holding parts ( 39 , 40 ) are moved away from one another by compressing the two handle levers ( 2 , 3 ), and a bore operating position in which the retaining ring holding parts ( 39 , 40 ) are actuated the handle lever ( 2 , 3 ) are moved towards one another, the switching device being designed such that a pin hole 19 of the right actuating lever ( 10 ) is provided with a right movable pin ( 20 ) which is connected to one of the right engagement holes ( 15 , 17 ) can be brought into engagement in the two support sections ( 2 a, 3 a), a pin hole ( 21 ) of the left actuating lever ( 11 ) is equipped with a left movable pin ( 22 ), which has one of the left engagement holes ( 16 , 18 ) in the two support sections ( 2 a, 3 a) can be brought into engagement, the two pliers front parts ( 27 , 35 ) having shaft sections ( 28 , 36 ), each of which has a connecting section at its proximal end len end, which can be rotatably and detachably inserted in guide holes ( 23 , 31 ) of the two actuating levers ( 10 , 11 ), the connecting sections ( 29 , 37 ) in the two pliers front parts ( 27 , 35 ) and sections ( 30 , 38 ) at the front in the guide holes ( 23 , 31 ) of the two actuating levers ( 10 , 11 ) are releasably attachable so that they are operatively rotatably coupled to each other, with right and left rotating shafts ( 24 , 32 ) being provided to effect that the two movable pins ( 20 , 22 ) move to engage one of the right engaging holes ( 15 , 17 ) or the left engaging holes ( 16 , 18 ) and surfaces to be engaged ( 56 , 63 ) are provided on the front sides of the two actuating levers ( 10 , 11 ), which are to be brought into engagement with engagement surfaces ( 55 , 62 ), which in turn are provided on the two pliers front parts ( 27 , 35 ) in order to di e to regulate the rotation of the two front parts of the pliers ( 27 , 35 ); wherein the connection between the connecting sections ( 29 , 37 ) and the sections ( 30 , 38 ) to be connected is formed by a first setting position in which the engagement surfaces ( 55 , 62 ) with the surfaces ( 56 , 63 ) to be engaged in Are engaged to block the rotation of the two tongs front parts ( 27 , 35 ) and by a second setting position in which the engagement between the engagement surfaces ( 55 , 62 ) and the surfaces to be brought into engagement ( 56 , 63 ) is released, a rotation of the two pliers front parts (27, 35) allow, and the coupling between the two pliers front parts (27, 35) and the two movable pins (20, 22) is such that if, in the second position, the two pliers front parts (27 35 ) are rotated so that the snap ring holding parts ( 39 , 40 ) are directed inward, the right movable pin ( 20 ) is moved into the pin hole ( 19 ) to over the pin hole ( 19 ) and the right one grip hole ( 17 ) of the left grip lever to engage while the left movable pin ( 22 ) is moved within the pin hole ( 21 ) to over the pin hole ( 21 ) into the left engagement hole ( 16 ) of the right lever ( 2 ) in To engage, and when the two pliers front parts ( 27, 35 ) are rotated in the second position so that the retaining ring holding parts ( 39 , 40 ) are directed inward, the right movable pin ( 20 ) moves within the pin hole ( 19 ) to engage through the pin hole ( 19 ) and the right engaging hole ( 15 ) of the right handle lever ( 2 ) while the left movable pin ( 22 ) is moved within the pin hole ( 21 ) to pass over the pin hole ( 21 ) and the left engagement hole ( 18 ) of the left handle lever ( 23 ) to engage. 5. Pliers according to claim 4, in which locks ( 58 , 65 ) are provided, which are moved within guide holes ( 23 , 31 ) of the two actuating levers ( 10 , 11 ), and elastically or resiliently in first recesses ( 57 , 64 ) and second recesses ( 60 , 61 ) of the shaft portions ( 28 , 36 ) of the two front parts of the pliers ( 27 , 35 ) lock without interfering with rotation and attachment or detachment of the front parts ( 27 , 35 ), the locking of the first Recesses ( 57 , 64 ) and the locks ( 58 , 65 ) is effected in the first setting position, and wherein the locking of the second recesses ( 60 , 67 ) and the locks ( 58 , 65 ) is effected in the second setting position. 6. Pliers according to one of claims 1 to 5, wherein the two pliers front parts ( 83 , 84 ) on the two actuating levers ( 10 , 11 ) are rotatably and releasably created, each having a narrow flat plate shape and at the front ends with retaining projections ( 85 , 86 ) are provided, the inner side surfaces of which are curved surfaces ( 87 , 89 ) which are curved in the width direction and the outer side surfaces of which are flat surfaces ( 88 , 90 ).