Joint structure

March 15, 1966

3,240,516

E. BAR1SH ETAL

JOINT STRUCTURE

Filed Oct. 4.. 1963

Sheets-Sheet 1

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ATTORNEYS

March 15, 1966

3,240,516

E. BARISH ETAL

JOINT STRUCTURE

Filed Oct. 4.. 1963

Sheets-Sheet 2

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FIG. 6

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FIG. 4

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ATTORNEYS

United States Patent Office „ 3,240,516

Patented Mar. 15, 1966

3,240,516 JOINT STRUCTURE

Emil Barish, 711 27th Ave., and Burton B. Rutkin, 2845 Pierce St., both of San Francisco, Calif., and Joseph A. Witt, 10935 Caloden St., Oakland, Calif.

Filed Oct. 4, 1963, Ser. No. 313,827 5 Claims. (Cl. 287—12)

This invention relates to a support structure and more particularly relates to a clamp structure having three or more independent joints wherein all of the joints are locked or unlocked by a single movement at one of the center joints. The invention is particularly adapted for use in surgical clamping techniques and will be so described although it will be understood to those skilled in the art that the support structure is one of general application.

In many surgical procedures it is necessary to hold some portion of the patient’s body in an exact position. Since the position may be extremely precise, it is customary to use a support having three or more separate joints therein so that great flexibility is achieved. The difficulty 'with the use of such supports as has heretofore been provided is that each of the joints, or at least each pair of joints, must be clamped with a separate movement so that after the patient is maneuvered into position it is still necessary to perform several operations to get all of the clamps fastened. Thus, there is a substantial delay and also the danger of moving the patient out of the exact position'desired.

In accordance with the present invention, a clamp is provided having three or more joints wherein all of the joints can be clamped by a single motion and unclamped by a single motion.

In the drawings forming a part of this application:

FIGURE 1 is a side view of a support embodying the present invention.

FIGURE 2 is an enlarged sectional view of one of the ball joints used at one end of the support shown in FIGURE 1.

FIGURE 3 is an enlarged sectional view of the center joint of the clamp shown in FIGURE 1.

FIGURE 4 is a sectional view on the line 4—4 of FIGURE 3.

FIGURE 5 is a sectional view on the line 5—5 of FIGURE 3.

FIGURE 6 is a sectional view, similar to FIGURE 4, showing an alternate form of wedging mechanism.

FIGURE 7 is a side view of another form of support embodying the present invention.

FIGURE 8 is an enlarged sectional view of the base member of FIGURE 7.

Referring now to FIGURES 1 through 5 by reference characters, there is shown a clamp mechanism having arms 10 and 12 which terminate in ball joints generally designated 14 and 16. The arms are supported by the central joint structure generally designated 18. The ball joint 14 supports a rod 20 to which is attached a clamp generally designated 22 which, in the embodiment shown, comprises a U-shaped member 24 having a set screw 26 in one arm thereof so that the member 22 can be readily clamped to a table or the like. The opposite ball joint 16 supports a rod 28 to which may be attached a surgical retractor 30. It will be understood, of course, that the clamp 22 and the retractor 30 are merely illustrative of devices which can be held by the rods 20 and 28.

The central joint structure is shown in detail in FIGURES 3, 4 and 5. The hollow arms 10 and 12 have enlarged end members 32 and 34 with central openings therein through which a shaft and wedges, hereinafter described, can pass. Additionally, the members 32 and 34 have conical or wedge shaped sides as at 36 and 38. The arms 10 and 12 have rods 40 and 42 therein which terminate in tapered inner ends 46 and 48. A central shaft 50 passes through the members 32 and 34 and two 5 truncated conical wedges 52 and 54 with their smaller ends facing together, as shown, are free to slide on the shaft 50. At the bottom of the shaft 50 is a threaded nut 56 while at the opposite end a washer 58 is free to slide on the rod. A pin 60 passes through the shaft 50 and an eccentric locking member 62 is pivoted on the pin 60. The eccentric locking member 62 has a handle 64 so that it can be turned by hand. It is apparent that as the handle 64 is turned on the shaft 60, the eccentric locking member 62 will cam against the washer 58, forcing the cones 52 and 54 toward each other. As this occures, the rods 40 and 42 will be forced outwardly by pressure of the cones against the bases 46 and 48 of the two rods. It is also apparent that because of the floating action of the cones on shaft 50, equal pressure will be exerted on both of the rods 40 and 42. Although the cones have been shown with the small ends facing each other and wtih means for forcing the cones together to clamp the joints, the reverse structure could also be used. Thus, the large ends of the cones could face each other with means, such as a differential screw, for forcing the cones outward to clamp the joint and vice versa.

In FIGURE 6, an alternate embodiment of the device is shown. Here a rectangular wedge 66 is employed rather than the conical wedge previously illustrated. Naturally, the enlarged members on the arms and the ends of the rods will be modified to mate against the square surface of the wedge rather than against the conical surface previously described.

In FIGURE 2, the construction of the ball joint 14 is shown. _ At the end of the arm 10 is the ball retainer 68 having inturned ends 70 for the retention of a ball 72, yet allowing the ball considerable movement. Retainer 68 is held by the threads 71 engaging an enlarged end 73 for ease of assembly and fine adjustment. The ball 72 is attached to the rod 20 by suitable means, or the ball and rod may be formed together. At the outer end of the rod 40 is an enlarged member 74 with a spherical surface adapted to mate with somewhat less than half of the ball 72. It is apparent that as the rod 40 is forced outwardly the ball 72 will be clamped between the end 74 of the rod 40 and the inturned end 70 of the ball retainer 68. Thus^ as rod 40 is pushed outwardly, the arm 20 will be held, in a desired position. Although not described in detail, the structure of the ball joint 16 is exactly the same as that described for the ball joint 14, outward movement of the rod 42 serving to clamp a ball in the joint 16, thus holding rod 28 in a fixed position.

In use, it is only necessary to move the retractor to a desired position and to then actuate the handle 64. As the handle 64 is turned, the eccentric locking member 62 will force the two cones together, which will result in a clamping of the joint 18 so that it can no longer turn, as well as exerting pressure outwardly on the rods 40 and 42 so that joints 14 and 16 will be clamped. Thus, a single movement of the handle 64 serves to lock all three joints. Because of the floating action of the cones, all of the joints will lock simultaneously and there is no possibility of one of the joints closing out first and preventing the locking of the other joints.

FIGURES 7 and 8, a different embodiment of the invention is shown wherein one end of the clamp terminates in a ball retainer and a split ball is used to secure the clamping action at that end. Here a hollow arm 76, which generally corresponds to the arm 10 previously described, has a split ball generally designated 78 at one

3,240,516 end thereof which fits into a socket 80. Socket 80 has a base 81 adapted to be screwed or otherwise fastened to a table or other suitable support. The ball 78 is split in two hemispheres, the upper of which 82 forms a part of the hollow arm 76 while the lower hemisphere designated 84 is adjacent to a rod 86 which generally corresponds to the rod 40 previously described. In this embodiment of the invention, as the rod 86 is forced outwardly, the split ball is squeezed in the socket 80, resulting in the clamping action. The other joints are clamped as previously described. It is obvious that either or both ends of the clamp may be provided with the split ball structure described.

It will be apparent to those skilled in the art that many changes may be made in the exact structure described without departing from the spirit of the invention. For instance, an eccentric or cam has been shown for clamping the two wedges together. Obviously, other hydraulic, mechanical or electrical means can be used to accomplish this action.

It is believed apparent from the foregoing that we have described a simple and effective clamp for surgical use and the like wherein a single movement serves to clamp a number of separate joints.