BACKGROUND OF THE INVENTION Retaining rings are utilized in annular grooves on shafts and ends of shafts to retain bearings, collars, and the like on the shaft. A retaining ring extends circumferentially between a pair of ends which are formed to have hubs. The hubs have apertures in which are inserted tips of a plier tool and force applied to either spread the hubs to expand the ring or squeeze the hubs to contract the ring, as necessary for installing the ring in and removing the ring from either external or internal grooves.

It is thus sometimes considered desirable to squeeze (move inwardly) the handles to effect movement of the jaws outwardly to expand the ring. It'is at other times considered desirable to squeeze the handles to effect movement of the jaws inwardly to contract the ring. Thus, it is desirable to provide a plier which is convertible between an external and an internal tool.

U. S. patents 4, 280, 265 and 4, 476, 750 disclose a pair of retaining ring pliers which utilize a pair of separate coplanar jaws and a pair of separate handles arranged about a common fixed pivot point having a pair of fulcrum points adapted to be changed to alternately engage one handle then another to change the fulcrum point to permit the changing of the tool from an

external to an internal tool. Two fulcrum pins are disposed in the jaws and adapted to alternately engage each set of handles to shift the fulcrum point from a position adapted to move the jaws inwardly as the handles are moved inwardly to a position where the jaws are moved outwardly as the handles are moved inwardly.

This patent discloses an alternative embodiment which has overlapping jaws about a common pivot, and the handles are moved relatively to the jaws such that the fulcrum point is shifted to an opposite side of the pivot by movement of the handles. A thumb nut is loosened in order to so shift the handles.

It may be difficult for the user of the pliers of the above patents to slide the pins into position. It may also be awkward and time-consuming for the user to loosen the thumb nut, shift the handles, and re-tighten the thumb nut.

What is needed is a convertible plier tool that is easier to manipulate between the internal and external configuration.

SUMMARY OF THE INVENTION The present invention meets the above-described need by providing first and'second jaws independently and rotatably disposed about a pivot. A separate pair of handles are rotatably disposed about the same pivot.

The handles attach on opposite sides of the jaws by a bolt that passes through openings in the handles and through the center of the jaws. The jaws have a recessed portion with a bearing surface that abuts with the tops of the handles. The handles are capable of being alternately engaged with the jaws such that the tool is changeable between a first position where the first jaw is engaged with the first handle and the second jaw is engaged with the second handle and a second position where the first jaw is engaged with the second handle and the second jaw is engaged with the

first handle. In this manner, the tool can be switched from an internal retaining ring plier to an external retaining ring plier. When the tool is set for external rings, the jaws move outwardly when the handle moves inwardly. When the tool is set for internal rings the jaws move inwardly when the handles are moved inwardly.

The jaws have openings at the back end for engaging with pivoting members attached to the handles.

In a preferred embodiment, a first pivoting member is attached to the first handle and has a pair of key members that are sized to fit into the openings in the back of the jaws to engage the first handle to the first jaw or the second jaw. The first pivoting member pivots about a centrally located pivot point such that when it is rotated in one direction one of its key members enters the first jaw. When the pivoting member is rotated in the opposite direction, the key member on the opposite side of the pivot enters the second jaw.

Accordingly, the key members on the first pivoting member enable the member to alternately engage with either jaw depending on which way the pivoting member is rotated.

A second pivoting member is attached to the second handle and pivots about a pivot point that aligns with the pivot point for the first pivoting member. The second pivoting member also has a pair of key members that operate in the same manner as described above such that the second pivoting member is capable of engaging the second handle to either the first jaw or'the second jaw depending on which way the second pivoting member is rotated. The second pivoting member has a lever arm attached to one end such that the member can be manually rotated from a first position where the second handle is engaged with the first jaw to a second position where the second handle is engaged with the second jaw. The second pivoting member also has a tooth extending therefrom.

The tooth on the second pivoting member causes a rocker to rotate in the opposite direction from the rotation of the second pivoting member. The rocker mechanically engages with the first pivoting member through a leaf spring or other device such that the rotation of the second pivoting member causes the first pivoting member to rotate in the opposite direction. In this manner, the pivoting members are always rotated in opposite directions by the single lever arm and the handles are therefore engaged to opposite jaws.

The leaf spring provides a force to both the first pivoting member and the tooth on the second pivoting member to hold the key members in engagement with the jaws so that they do not slip out of engagement during use.

In an alternate embodiment, a pair of levers are provided for manual manipulation of both pivoting members.

Another alternate embodiment provides a plier tool having a single coil spring that operates the pivoting members and biases the handles away from one another.

The coil spring has a pair of arms extending from opposite ends of the spring. The tension on the spring urges the arms to rotate toward each other. One of the arms is attached to a first pivoting member attached to a first handle. The other arm is attached to a second pivoting member attached to the second handle. The pivoting members pivot about a common pivot point disposed in spaced apart relation from the pivot point of the jaws and handles. The plier tool switches from internal to external by pushing or pulling the spring inward or outward along an axis normal to the pivot axis of the jaws and', handles.

The position of the attachment point of the arms to the pivoting members relative to the pivot point for the pivoting members determines whether the tool is in the internal or the external configuration. If the spring

is pushed inward toward the jaws, the arms will provide a force in a first direction about the pivot point for the pivoting members. If the spring is pulled to the other side of the pivot point for the pivoting members, the arms will provide a force causing the pivoting member to rotate in the opposite direction.

The force of the spring transmitted through the arms also causes a moment-arm about the pivot point for the handles that urges the handles apart from each other.

BRIEF DESCRIPTION OF THE DRAWINGS The invention is illustrated in the drawings in which like reference characters designate the same or similar parts throughout the figures of which : Fig. 1 is a plan view of a retaining ring plier that embodies the present invention ; Fig. 2 is a cutaway plan view of the present t invention ; Fig. 3 is a plan view of the first pivoting member and the first handle of the present invention ; Fig. 4 is a plan view of-the second pivoting member and second handle of the present invention ; Fig. 5 is a plan view of the first pivoting member ; Fig. 6 is a plan view of the rocker ; Fig. 7. is a plan view of the second pivoting member ; Fig. 8 is a plan view of an alternate embodiment of the present invention ; Fig. 9 is a partial plan view of the alternate embodiment ; Fig. 10 is a plan view of the second pivoting member and the second handle for the alternate embodiment ; Fig. 11 is a plan view of another alternate embodiment of the present invention in a first position ;

Fig. 12 is a partial plan view of the alternate embodiment in the first position ; Fig. 13 is a partial plan view of the alternate embodiment in the first position ; Fig. 14 is a plan view of the alternate embodiment in a second position ; Fig. 15 is a partial plan view of the alternate embodiment in the second position ; Fig. 16 is a partial plan view of the alternate embodiment in the second position ; Fig. 17 is a plan view of an additional embodiment ; and, Fig. 18 is a view taken along line 18-18 of Fig.

17.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to Fig. 1, there is shown generally a plier tool 20 used for inserting and removing a retaining ring. The plier 20 has a pair of right and left jaws 23, 26 respectively. A pair of tips 29 extend from the forward ends of the jaws 23, 26. The tips 29 terminate in reduced diameter portions 32 that are inserted into the retaining ring apertures. The jaws 23, 26 are opened (tips moved farther apart) and closed (tips moved closer together), as described hereinafter, to spread and contract the retaining rings.

The jaws 23, 26 are controlled by a set of handles 35, 38. For internal rings it is desirable to have the jaws 23 and 26 move inwardly when the handles 35, 38 are moved inwardly. In contrast for external rings, it is desirable to have the jaws 23, 26 move outwardly when the handles 35, 38 move inwardly. A set of indicia 41 indicates to the user whether the plier tool 20 is in the internal or external configuration. A spring 44 is connected between the handles 35, 38 to bias the handles away from each other.

Turning to Fig. 2, the jaws 23, 26 are independently and rotatably disposed about a pivot 47 that is formed by a bolt 50. A curved section 53 on each jaw 23, and 26 provides a bearing surface for rotation of the jaws 23, 26 about the bolt 50. The bolt 50 secures the jaws 23, 26 between the handles 35, 38 by extending through the jaws 23, 26 and through openings 56 in the handles. The jaws 23, 26 preferably have a recessed portion 59 that provides a bearing surface 62 for contact with the tops of the handles 35, 38.

The ends of the jaws 23, 26 have openings 65. A first pivoting member 68 is attached to handle 35, and a second pivoting member 71 is attached to handle 38. The pivoting members 68, 71 pivot about a pivot point 74 and are capable of engaging with the openings 65 in the jaws 23, 26 by means of key members 77. The key members 77 are disposed on each of the pivoting members 68, 71 on opposite sides of the pivot point 74. Rotation of the pivoting members 68, 71 about the pivot point 74 causes one of the key members 77 to enter one of the jaws 23, 26 and causes the opposite key member 77 to be removed from the jaws 23, 26. Accordingly, by rotating the first pivoting member 68 about its pivot point 74 the first handle 35 can be engaged alternately to the right jaw 23 or to the left jaw 26. Likewise, rotation of the second pivoting member 71 about the pivot point 74 enables the second handle 38 to be alternately engaged with either the right jaw 23 or the left jaw 26.

Turning to Fig. 3, the first pivoting member 68 is pivotally attached to the inside of handle 35. The pivoting member 68 rotates about the pivot 74.

In Fig. 4, the second pivoting member 71 is pivotally attached to the inside of handle 38. The second pivoting member 71 has a lever arm 80 that provides a leverage point for rotating the second pivoting member 71 about its pivot point 74. The second pivoting member 71 also has a tooth 83 extending

therefrom. When the second pivoting member 71 is rotated, the tooth 83 drives a rocker 86 that is pivotally attached to the handle 38 below the second pivoting member 71.

The rocker 86 has an opening 89 for receiving the tooth 83 in a gear-type arrangement. Other mechanical arrangements for engaging the second pivoting member 71 to the rocker 86 would also be suitable as known to those of skill in the art. The rocker 86 has a leaf spring 91 attached thereto. The leaf spring 91 is preferably W-shaped with a pair of legs 92 and a shorter intersection point 95 disposed between the legs 92. The ends of the legs 92 abut with the first pivoting member 68 when the plier tool 20 is assembled (best shown in Fig. 2). Accordingly, rotation of the second pivoting member 71 by means of its lever arm 80 causes rotation of the first pivoting member 68 through the operation of the rocker 86.

The leaf spring 91 engages with both pivoting members 68, 71 to hold the key members 77 in engagement with the jaws 23, 26. The ends of the legs 92 alternately engage with the bottom of the first pivoting member 68 and the force of the spring 91 pushes the key member 77 into the opening 65 in the jaw. At the same time, the intersection point 95 of the leaf spring 89 provides a force to the tooth 83 on the second pivoting member 71 that pushes it into engagement with the jaw.

Returning to Fig. 2, the plier tool 20 is''converted from an internal to an external configuration by moving the lever arm 80 that pivots the second pivoting member 71. The rotation of the second pivoting member 71 causes the tooth 83 to rotate the rocker 86.'When the rocker 86 is rotated, the spring 91 comes into contact with the first pivoting member 68 and the tooth 83. The leg 92 of the spring 91 engages the underside of the first pivoting member 68 and provides a force in the direction of arrow 98. At the same time, the

intersection point 95 provides a force against the tooth 83 in the direction of arrow 101. The force against the tooth 83 prevents the second pivoting member 71 from rotating out of engagement with the jaws. To switch between the configurations, a sufficient amount of force to overcome the force of spring 91 is manually applied to the lever arm 80 to rotate the second pivoting member 71 into the opposite position. Once the pivoting member 71 is rotated a sufficient distance beyond the pivot point 74, the force of the spring against the tooth 83 and the first pivoting member 68 holds the key members 77 on the respective pivoting members into engagement with the jaws 23, 26.

In Fig. 5, the preferred shape of the first pivoting member 68 is shown. The first pivoting member 68 pivots about its pivot point 74. The key members 77 are formed on opposite sides of the pivot point 74 such that rotation of the pivoting member 68 alternately brings the key members 77 into engagement with the openings 65 in the back of the jaws 23, 26. Turning to Fig. 6, the rocker 86 transmits the rotary motion of the second pivoting member 71 to the first pivoting member 68 through a leaf spring 91. In Fig. 7, the second pivoting member 71 is shown with the tooth 83 and the key members 77 projecting therefrom. The key members 77 are positioned on opposite sides of the pivot point 74 such that rotation of the second pivoting member 71 about the pivot point 74 causes the key members 77 to alternately engage with the openings 65 on the back of the jaws 23, 26. Rotation of the second pivoting member 71 causes counterrotation of the first pivoting member 68 through the tooth 83. In this manner, the key members 77 on the first pivoting member 68 are oriented opposite to the key members 77 on the second pivoting member 71 such that the handles 35, 38 are always engaging different jaws 23, 26. Accordingly, when

handle 35 is engaging jaw 23, handle 38 is engaging the opposite jaw 26 and vice versa.

In Fig. 8 an alternate embodiment of the present invention is shown. The plier tool 200 has a first lever arm 203 and a second lever arm 206 for switching the tool between the internal and the external configuration. A set of indicia 209 indicates the configuration of the tool. A right jaw 212 and a left jaw 215 pivot about a pivot point 216. The pivot point is preferably provided by a bolt 217. The jaws 212, 215 have tips 218 with a reduced diameter section 221 for engaging with the apertures in standard retaining rings.

The jaws 212, 215 rotate independently about the pivot 216 and are held in position by the bolt 217 which extends through the center of the jaws and through openings 222 in handles 224, 227. The jaws have a recessed portion 228 with a bearing surface 229 that abuts with the top of the handles 224, 227. The jaws 212, 215 are capable of being alternately engaged by handles 224 and 227 to switch between internal and external mode.

When the tool 200 is in the external configuration, the jaws 212, 215 move outwardly when the handles 224, 227 are moved inwardly. When the tool 200 is in the internal configuration, the jaws 212, 215 move inwardly when the handles move inwardly.

A spring 230 is disposed between the handles 224, 227 to bias the handles 224, 227 apart from one another.

The handles 224, 227 have plastic covers 233 that provide for better gripping and cushioning for the user.

Turning to Fig. 9, lever arm 203 extends from a first pivoting member 236 and lever arm 206 extends from a second pivoting member 239. The pivoting members 236, 239 rotate about a pivot point 242. Each of the pivoting members 236, 239 has a pair of key members 245 extending therefrom and sized to be capable of engaging with openings 248 in the jaws 212, 215. The tool 200 is

switched between the internal and external configuration by manually rotating the lever arms 203, 206 on each pivoting member 236, 239 such that the key members 245 engage with the jaws 212, 215.

In Fig. 10, the first pivoting member 236 and first handle 224 are shown.

In operation, the jaws 212, 215 are alternately engaged by the first and second handles 224, 227 depending on the position of the pivoting members 236, 239 which are manually controlled by the lever arms 203 and 206.

Another alternate embodiment of the present invention is shown in Figs. 11-16.

In Fig. 11, a plier tool 300 has a right jaw 303 and a left jaw 306 that are independently and rotatably disposed about a pivot 312. The jaws 303, 306 are preferably separately disposed about a bolt 315 and between a pair of handles 318 and 321 that are also separately and rotatably disposed about the pivot 312.

The handles 318, 321 have openings 324 through which the bolt 315 passes. The handles 318, 321 hold the jaws 303, 306 in position about the bolt 315. The jaws 303, 306 have a recessed portion 327 with a bearing surface 330 that abuts with the top of the handles 318, 321.

The back of the jaws 303, 306 have openings 333.

The tool 300 is switched between the internal and the external configuration by pushing or pulling a spring 336 between a first position and a second position. The first position is shown in Figs. 11-13 and the second position is shown in Figs. 14-16. The spring 336 has a first arm 339 and a second arm 342 that extend from opposite ends of the spring 336. The spring 336 is wound such that the force of the spring 336 urges the two arms 339, 342 to rotate toward each other.

In the first position (best shown in Fig. 11), the arms of the spring 336 terminate at a position between the jaws 303, 306 and a pivot point 343. In the second

position (shown in Fig. 14), the arms 339, 342 for the spring 336 terminate at a position on the side of the pivot point 343 opposite the jaws 303, 306.

Turning to Fig.. 12, a first pivoting member 345 is attached to handle 318. The first arm 339 is attached to the first pivoting member 345 such that the force of the spring 336 acts upon the member 345 along the line indicated by arrow 346 to cause it to rotate about its pivot 343, as indicated by arrow 347. The force of the spring 336 also creates a moment-arm about pivot 312 that urges the handle 318 to rotate in the direction of arrow 351.

In Fig. 13, a second pivoting member 354 is attached to handle 321. The second arm 342 is attached to the second pivoting member 354 such that the force of the spring 336 acts upon the member 354 along the line indicated by arrow 357 to cause it to rotate about the pivot 343, as indicated by arrow 358. The force of the spring 336 also creates a moment-arm about pivot 312 that urges the handle 321 to rotate in the direction of arrow 360.

Turning to Fig. 14, the plier tool 300 is in the second position where the spring 336 is pulled along the direction indicated by arrow 363 to position the arms 339, 342 of the spring 336 on the side of the pivot 343 opposite the jaws 303, 306. In this position, the pivoting members are caused to rotate in the opposite direction from the first position such that the jaws engage with opposite handles. In Fig. 15, the force of the spring 336 along the line indicated by arrow 344 causes the first pivoting member 345 to rotate in the direction of arrow 366 on the first handle 318. The force of the spring 336 again produces a moment-arm that urges the handle 318 in the direction of arrow 351.

In Fig. 16, the arm 342 of the spring 336 causes a force along the line indicated by arrow 361 that causes the second pivoting member 354 to rotate in the

direction of arrow 369. The force of the spring 336 again produces a moment-arm that urges the handle 321 to rotate in the direction of arrow 360.

Turning to Fig. 17, a pair of tips 400 and 403 have reduced diameter portions 406 that are inserted into the retaining ring apertures. The reduced diameter portions 406 are angled away from each other for external rings.

For internal rings, the tips 400, 403 are rotated 180 degrees such that the reduced diameter portions 406 are angled toward one another and almost in contact with each other.

The tips 400 and 403 preferably contain color coded indicia 409 for internal and external positioning of the tips that correspond to color coded indicia 412 for the internal and external engagement of the jaws and handles. The tips 400 and 403 preferably have one color on one side and another color on the opposite side. The right jaw 415 and left jaw 418 have openings 419 for a set screw 421 and sight openings 424. The sight openings 424 align with the color indicia 409 when the tips 400 and 403 are inserted fully into the jaws 415, 418. If the tips 400 and 403 are installed properly, the color visible in the sight opening 424 matches the color indicia 412. 1 Turning to Fig. 18, the indicia 409 are disposed on both sides of the tips. To switch from internal to external the tip is removed from the jaw and rotated 180 degrees.

The present invention provides several advantages, including ease of use, reliability, and ease of manufacture. The single lever embodiment provides for easier switching between the internal and external configuration by means of manually rotating a single lever arm. The alternate embodiment also provides for easier switching by means of pushing or pulling a coil spring a short distance from one side of a pivot to the other side.

While the invention has been described in connection with certain preferred embodiments, it is not intended to limit the scope of the invention to the particular forms set forth, but, on the contrary, it is intended to cover such alternatives, modifications, and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims.