US3188077A - Work holding fixture - Google Patents

Description

J 9 .5 P. E. OLSON 3,188,077

WORK HOLDING FIXTURE Filed Dec. 20, 1961 2 Sheets-Sheet l v w y Y m 19 m 4 I i\ ,i i

l 6 L Ara/J? I l J (37 j as @5 I I I I I zo 31 17 211 15 20 L 12. 14 f 11 2 10 --30' I f '31 11 -a5 L\\\\\\\\\\\\\ v r 7 1 $53 I? v PHILIP E.

June 8, 1965 p OLSQN WORK HOLDING FIXTURE 2 Sheets-Eihaet 2 Filed D60. 20, 1961 3,188,077 WQRK HOLDING FIXTURE Philip E. Olson, Rockford, Ill., assignor, by memo assignments, to Rockford Machine Tool Co., a corporation of Iilinois Fiied Dec. 20, 1961, Ser. No. 160,720 3 (Ilaims. (Cl. Z69226) This invention relates to work holding fixtures and more particularly to a fixture for use in a metal cutting planer or the like.

It is the general object of the invention to provide a new and improved work holding fixture adapted to clamp and lock one or more work pieces with considerable force.

It is another object to provide such a fixture with means for breaking the clamping lock on the work piece to permit removal thereof.

Other objects will become readily apparent from the foilowing description, taken in connection with the accompanying drawings, in which:

FIGURE 1 is a fragmentary plan view of a preferred form of the invention;

FIGURE 2 is an enlarged end elevation, partly in section, along line 22 of FIGURE 1;

FIGURE 3 is an enlarged section along line 3-3 of FIGURE 1; and

FIGURE 4 is a fragmentary view along line 4-4 of FIGURE 3.

As shown in the drawings, the invention comprises an attaching plate 10 and a base 11 secured thereto. The base has a pair of opposed flanges 12 and 13 which form the outer stationary jaws of a pair of vises 14 and 15. There are preferably a plurality of movable jaws for each vise, herein shown in the form of members 16 and 17 for the vise 14, and members 18 and 19 for the vise 15. The jaw members 16 and 17 are slidably supported and guided in pairs of upstanding portions 20 and 21 on the base 11 for movement towards and away from the stationary vise jaw 12. Similarly, the jaw members 18 and 19 are slidably supported and guided in pairs of upstanding portions 22 and 23 on the base 11.

A high torque electric motor 25 is adapted to actuate the jaw members 16 and 18 and a similar high torque electric motor 26 is adapted to actuate the jaw members 17 and 19. V

The actuating or drive mechanisms between the motors and the movable jaw members are of a high torque multiplying type so that by the use of high torque motors extremely strong clam-ping action is obtained upon work pieces when placed in the Vises. The drive mechanism, as shown in FIGURE 2 for the jaw member 16, comprises a screw and nut device with a nut element 27 carried on the jaw member and secured thereto by screws 28. The screw element 29 is formed on a shaft 30 which has splines 30 thereon and has a worm wheel 31 splined thereto and also has a portion at its other end forming the screw element 32 of a similar screw and nut device for the jaw member 18. The worm wheel is rotatably supported on ball bearings 33 and 34 supported in a gear casing 35 which in turn is fixed to the base 11. A worm 36, meshing with the worm wheel 31, is formed on a shaft 37 which is supported in the gear casing 35 on antifriction bearings 38 and 39 (FIGURE 3).

United States Patent ice In order to facilitate the unclamping of work pieces in the Vises, a lost motion device is provided in the drive mechanisms. As shown best in FIGURES 3 and 4, the drive mechanism includes a pinion 40 on the shaft 41 of the motor 26, and a meshing gear 42 supported on a sleeve bearing 43 carried on a hub 44 keyed at 45 to the Worm shaft 37. A drive pin 46 is screwed to the gear 42 in an eccentric position on one side thereof so as to move in a circular path adjacent the gear. An arm 47 is formed integrally with the hub 44 and extends radially therefrom into the path of the pin 46. Thus the gear 42, from a position wherein the pin 46 is against one side of the arm 47, can turn through most of a full revolution in a reverse direction before the pin engages the other side of the arm. This affords time for the motor to accelerate in the opposite direction and enables the pin to produce a hammer-blow on the arm to break the friction in the drive mechanisms and unclamp work in the vises.

To insure equal pressure on the movable jaw members of both vises, the splines 30' are shorter than the hub 31 of the worm wheel 31, thus enabling the shaft 30 to move laterally from .the position shown in FIGURE 2.

In operatiomwith the movable jaws withdrawn, work piecesmay be placed in the Vises 14 and 15. Upon energization of the motors 25 and 26 in a forward direction, the jaws 16 and 17 move to close the vise 14 and the jaws 18 and 19 move to close the vise 15 on the work pieces. During this operation the drive pin 46 of the lost motion device is in engagement with one side of the arm 47 and the high torque of the motors and the high torquemultiplying gearing produce an extremely strong clamping force in the vises. After the cutting operations have been performed on the work pieces, reversal of the motors to unlock the vises, produces hammer-like unlocking blows by the lost motion devices, thus insuring the opening movements of the jaw members.

I claim:

1. A work holding fixture comprising, in combination, a base having means thereon forming one jaw of a work holding vise, a member slidable on said base forming the opposite jaw of said vise and means for moving said slidable jaw member comprising a screw and nut device, one element of which is carried on said jaw member, a worm and worm wheel device having the worm wheel connected to the other element of the screw and nut device, a high torque electric motor having a pinion on its shaft meshing with a gear rotatably mounted on a shaft carrying said worm, and a lost motion drive means between said gear and shaft comprising a drive pin positioned eccentrically on one side of said gear and an arm fixed to said shaft and extending radially therefrom in the path of said drive pin.

2. A work holding fixture comprising, in combination, a base having means thereon forming one jaw of a work holding vise, a member slidably mounted on the base forming the opposite jaw of said vise, first means to move said member, reversible power operated means, gearing means connecting said power operated means to said first means and including a lost motion device on said gearing, said lost motion device having a drive pin affixed to the gearing means and a two-sided arm afiixed to said first means so that when said power operated means drives said gearing in one direction, the drive pin arsaow a base having means thereon forming one jaw of a work 10 holding device, a member slidably mounted on the base forming the opposite jaw of said vise, first means to move said member, a high torque reversible electric motor, and gearing means connecting said motor to said first means including a pinion on the motor shaft meshing with a gear rotatably mounted on a'parallel shaft, and a lost motion device on said gearing means between said gear and said parallel shaft to drive said first means in either a clockwise or counterclockwise direction depending on the direction of said high torque reversible electric motor.

References Cited by the Examiner UNITED STATES PATENTS 705,197 7/02 Blood 269-224 X 1,635,758 7/27 Lemon 74425 X 2,238,434 4/41 Oberhofiken 269142 X 2,793,551 5/57 Ford 81-52.? 2,929,298 3/60 Hill 269l52 X 3,063,708 11/62 Wollenhaupt 269--216 ROBERT C. RIORDON, Primary Examiner.

5 THOMAS J. HICKEY, Examiner.

Claims (1)

1. A WORK HOLDING FIXTURE COMPRISING, IN COMBINATION, A BASE HAVING MEANS THEREON FORMING ONE JAW OF A WORK HOLDING VISE, A MEMBER SLIDABLE ON SAID BASE FORMING THE OPPOSITE JAW OF SAID VISE AND MEANS FOR MOVING SAID SLIDABLE JAW MEMBER COMPRISING A SCREW AND NUT DEVICE, ONE ELEMENT OF WHICH IS CARRIED ON SAID JAW MEMBER, A WORM AND WORM WHEEL DEVICE HAVING THE WORM WHEEL CONNECTED TO THE OTHER ELEMENT OF THE SCREW AND NUT DEVICE, A HIGH TORQUE ELECTRIC MOTOR HAVING A PINION ON ITS SHAFT MESHING

Images