US2512753A - Mechanism for clamping and operating on workpieces - Google Patents

Description

June 27,1950 T m- 2,512,753

MECHANISM FOR CLAMPING ANDOPERATING N WORKPIECES Original Filed March 10, 1945 s She'ets-Sheet 1 [nu enZOr [3L Laurence E 9/7077? U i @v his Atwrne MECHANISM FOR CLAMPING AND OPERATING 0N WORKPIECES 7 Original Filed March 10, 1945 L. E. TOPHAM June 27, 1950 3 Sheets-Sheet 2 0 2 0 0 0 i 7., L- 2 50mm? czr w imws 4, w! l l Ifilll I l l I1. 2/ 0 6 Ir x G Inventor" Laurence E. T

June 27, 1950 L TQPHAM 512,753

MECHANISM FOR CLAMPING AND OPERATING 0N WORKPIECES Original Filed March 10, 1945 3 Sheets-Sheet 5 Inventor Laurence E Top/29777 Patented June 27, 1950 r U i'i TENT OFFICE 'MEGHANISM FOR GLAMPING AND OPERAT- ING-N WORKPIECES 4 Claims; (Cl. IMP-93) This invention relates toan improved mechanism for clamping and operating on work parts and is herein illustrated as applied to 1ast=d'r'illing machine of the type disclosed inan application for Letters Patent oi the United States, Se rial No. 582,011, filed on March 10, 1945, of which this application is a division. Itwill'be understood, however, that this invention is not limited to machines of particular type but is broadly applicable in any machine having a power driven tool for performing an operation on a workpiece, a support for the work piece adapted to present the work piece to the tool and' mechanismfor moving the tool into and out of engagement with the work piece.

It is the purpose of the invention to provide'a simple yet effective mechanism insuring that the work piece will be firml clamped upon the sup port and that the tool cannot be moved into operative engagement with the work piece unless and until the latter is firmly clamped inoperative position on the support.

To this end and in accordance Withthe invention, there is provided a Work. clamping member which is moved into clamping engagement with the work piece on the support by operator controlled mechanism. "This operator -controlled mechanism includes connections to mechanism for moving the tool into 'engagement wi-th the work piece, and these'connections-are "so-con-- structed and arranged that on op eration of the operator controlled mechanism the "clamping member is first moved into clampingengagenient with the work piece and then automatically locked in work clamping position, whereupon*co tinued operation of the operator controlled mechanism causes movement of the tool into operative engagement with the work.

' These and other features of the inventionwill now be described in detail in connection with the accompanying drawings and wilI'be-pointed 'out in the appended claims.

In the drawings,

Fig. 1 is a view, substantially infr'ont elevation, of a last drilling machinein which the' 'invention is shown as embodied;

Fig. 2 is a detail view, in front elevation; ot a holddown mechanism and drill elevating niechanism associated therewith;

Fig. 3 is a plan view of the parts substantially as shown in Fig. 2; and

Fig. 4 is a detail view partlybro'kenaway ahd in cross section, taken along the lineIV- IV-oT Fig. 3, viewed in the direction of theiar'r'ows. I

The illustrated last drilling machine serves to bore a thimble hole intothe top 'face or cr'own I of the heel and of a'shoelast Lrestingbbttom up on a-lastsupport' P with which the machine'is provided.

The frame; of the illustrated machine comprises a base It (Fig. 1) to Which-is secured an upright column I 2. For supporting the drill'head of the machine there is provided a bracket '14 (Figs. 1, 2 and '3). The bracket I4 is clamped to the column l2 by'bolts l6 and extends radially therefrom. For carrying the last support a i bracket I8 is provided which'is also secured tothe column I2'and extends radially 'therefrom at an acute angle to the bracket [4. Both brackets-l4 and It are secured together by vertical screw bolts 28.

The operating mechanism of the illustrated machine comprises an upwardly extending, vertically movable rotary dri1l' 2-2 (Figs. land 2) which is secured in a chucki i provided on the upper end of a rotary drill shaft 26. The shaft 26*has an chlarg'ed-portion-Zfi which is'ro'tatably mounted and axially slidable in a bearing provided in the bracketl t. The lowerendof the shaft ZE-car'ries a bank'oi'stepped'pulleys=30 of different diameters and, hence, different peripheral speeds. The pulleys are splined'onthe shaft 26, the arrangement being so that the pulleystil are constrained to rotate with-the shaft 26' but the-shaft can move in the direction of the axis of rotation withrelation to'the pulleys '30,

this to feed the'drill '22 into the work. The pillleys'30 are driven' by a belt '32 connecting a selected one of the pulleys 30"with a selected pulley of a similar-but invertedbank of 7 s'tepped 'pulleys 34- securedon the rotor shaft of amotortt. The

' motor 36 is fastened to an extension 38 of the treadle 42 "is'pivotally' secured at 'M 'to 'a small bracket lfi fastened to the column '12.

"Th'e' -illustrated machine is providedwith a holddown mechanism which serves to su'pport the last-mounted on the last support? againstthe thrust Ofthe'driII 'ZZ during the drilling operati'on. Refei' ring to t'he drawings, itwi1l be noted jection 65 provided on the sleeve 60 with a pin secured in a socket 68 provided on the lever 52. The spring 64, in pulling up on the lever 52, elevates the fulcrum stud 54 by rocking the lever 56 about its pivot screw 58 until the rear end of the lever 56 strikes a projection 19 provided on the sleeve 6t.

To move the holddown 59 into contact with the heel seat portion of the last L supported in the machine, there is provided a rod 12 which is pivotally secured by a stud T4 to the arm of the lever 52 on which the holddown 59 is provided. Upon downward movement of the rod 12, the lever 52 is rotated in a counterclockwise direction, as viewed in Fig. 2, about the stud 56. At the same time, the lever 56 is rotated in a counterclockwise direction and its rear arm is moved out of contact with the abutment i9. To move the rod 12 downward, it is provided at its lower end with a fork it which is pivotally connected by a stud 18 to a lever 30 pivotally movable at one end about a stud 82. The other end of the lever 89 is pivotally connected to a treadle rod 84 which at its lower end is pivotally connected to the above described treadle 32. A spring lit connecting the treadle 42 with a bracket 83 secured to the column [2 serves to elevate the treadle into its normal inoperative position, thereby elevating the holddown.

To lock the holddown Elli in last contacting position, a pawl St is provided which is movable about a fixed stud 92 and which is arranged to be moved beneath the right hand arm of the lever 52 (as viewed in Figs. 1 and 2) after the holddown 58 has been moved into contact with the last. For the purpose of controlling the movement of the pawl 96] it is provided with a substantially horizontal arm which is secured by means of a screw 94 to one arm of a two-armed lever 96 which is also pivoted on the fixed stud 92. The pawl 95! is adjustable with relation to the lever 99 and to this end the horizontal arm of the pawl is provided with a vertically extending slot 98 receiving the screw 94. The screw 94 when tightened secures the pawl to the lever 96 in the selected position of adjustment. The right hand arm of the lever 96 is connected by a spring 388 with the above mentioned abutment ill on the sleeve 69. The sprin Ill!) tends, after the holddown has been moved into contact with a last mounted on the last support P, to swing the lever 96 in a counterclockwise direction, as viewed in Fig. 2, to move the pawl 90 beneath the right hand arm of the lever 52 and to prevent clockwise rotation of the lever 52 as a result of which the holddown would be raised from the last. In the inoperative position of the parts (Fig. 2), the left hand extremity of the lever 96, which is fork shaped and rests on the flat top face of the fork shaped end it of the rod 12, is prevented from moving down so as to swing the pawl 90 into looking position because the rod 12 and the fork shaped end it are in their elevated positions. However, after downward movement of the rod 12 and counterclockwise movement of the lever 4 52 to move the holddown 583 into contact with the last, both the lever 96 and the pawl 90 are now free to be rotated in a counterclockwise direction about the stud 92 by the spring $00, thus locking the lever 52 and the holddown 56 in operative positions.

The above described mechanism for moving the hOlddOWn 50 into last engaging position and for holding it in that position is connected with mechanism for elevating the rotary drill 22 so as to feed it into the work. It should be noted that the above mentioned pivot stud 82 is only stationary so long as the lever 52 is rotated in a counterclockwise direction to move the holddown into last engagement. After the holddown is in engagement with the last and the lever 52 has been locked by the pawl 90 so that it can rotate neither in. one direction nor the other, the rod 12 no longer can be moved downward and, consequently, the pivot stud 18 now becomes a fixed fulcrum about which the lever 88 is rocked in a counterclockwise direction upon continued movement of the treadle rod 84. The result is an elevation of the pivot stud 82. The latter is connected me which meshes with a pinion lit (Figs. 3 and l) formed on a countershaft H2 rotatable in hearings in the bracket 4. The pinion H0 meshes with a rack ii l provided on the portion 28 of the shaft 25. Consequently, on elevation of the pivot stud 82 after the holddown has been moved into last engagement and locked, the arm H34, as a result of the continued downward movement of the treadle rod 84, is rotated to elevate the drill shaft 26 through the agency of the gear segment H33, pinion lid and rack H4. The advantage of this mechanism is that both the looking of the last L against the thrust of the drill 22 and the feeding of the drill are effected by one continuous treadle operation and that the drill cannot be fed into the last until after the last has been engaged by the holddown and the holddown has been locked in last engaging position.

In the operation of the machine a last L to be drilled is mounted on the last support P. Thereafter the treadle 4-2 is depressed with the result that the holddown 50 is brought down into engagement with the heel seat portion of the supported last and is locked in last engaging position as described.

By the continued depression of the treadle the drill 22, which is continuously rotated, is elevated to engage the top face of the heel end of the last and is fed into it so as to bore a thimble hole into the last. This having been accomplished, the treadle 42 is released and is pulled up by the spring 86 with the result that the drill is lowered. After the drill has been lowered into its inoperative position, continued upward movement of the treadle 42 causes the positive unlocking of the lever 52 by the engagement of the upwardly moving fork T5 with the latch controlling lever 96. Finally, the holddown 5D is swung upward and its floating fulcrum stud 54 is elevated by the spring 64 until the arm of the lever 56? again engages the abutment 19.

Having described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. In a machine for operating on a work piece, a support for the work piece, a tool movable with relation to the support to operate on the work piece, means for so moving the tool, a clamp adapted to engage the Work piece on the support to hold the work piece against the thrust of the tool, means for moving the clamp into engagement with the work piece, a latch for locking the clamp in work-engaging position, a connection between the clamp-moving means and the latch for rendering the latch operative on movement of the clamp into work-engaging position, a connection between the clamp-moving means and the tool-moving means, and means active after the clamp has been locked to render the last-mentioned connection effective to move the tool with relation to the support.

2. In a machine for operating on a Work piece, a support for the work piece, a tool movable with relation to the support to operate on the work piece, a clamp for holding the work piece on the support against the thrust of the tool, clampoperating means, tool-operating means, an operating lever, a connection between the lever and the clamp-operating means, another connection between the lever and the tool-operating means, and an operator-controlled means for rotating the lever about the last-mentioned connection to operate the clamp and then for rotating the lever about the first-mentioned connection to operate the tool.

3. In a machine for operating on a work piece, a support for the work piece, a tool movable with relation to the support to operate on the work piece, a clamp for holding the work piece on the support against the thrust of the tool, clampoperating means, tool-operating means, a latch for locking the clamp in work-clamping position, a spring tending to move the latch into locking position, a link connecting the latch with the clamp-operating means and normally holding the latch out of its locking position, an operating lever, a connection between the lever and the clamp-operating means, another connection between the lever and the tool-operating means, and operator-controlled means for rotating the lever about the last-mentioned connection to operate the clamp and permit the spring to move the latch into its locking position and for then rotating the lever about its first-mentioned connection to operate the tool.

4. In a machine for drilling the heel ends of lasts, an upwardly extending and upwardly movable drill, a last support for presenting a last to the drill in a position for the drill to bore a thimble hole into the top face of the heel end of the last, a holddown for holding the last on the support against the upward thrust of the drill, means for moving the holddown into engagement with the last prior to the initiation of the last-drilling operation, means for moving the drill upwardly, a latch for locking the holddown in last-engaging position, a connection between the holddownmoving means and the latch for rendering the latch operative on movement of the holddown into work-engaging position, a connection between the holddown-moving means and the drillmoving means, and means active after the holddown has been locked to render the last-mentioned connection effective to move the drill upwardly.

LAURENCE E. TOPHAM.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,427,805 Hadaway et a1 Sept. 5, 1922 1,973,204 Goss et a1 Sept. 11, 1934 2,174,602 Seely Oct. 3, 1939 2,350,002 Van Sittert et a1. May 30, 1944 2,387,102 Wallis Oct. 16, 1945

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