US2278643A - Press unloader - Google Patents

Description

April 7, 1942. F. w. BRAUN 2,278,643" PRESS UNLOADER Filed Jan. 22, 1940 2 Sheets-Sheet 1 April 7, 1942. FQ w. vBRAUN 2,2 78,643,

PRESS UNLOADER VFil-ed Jan. 22, 1940 2 Sheets-Sheet-2 Patented pr. 7, 1942 r l" PRESS UNLOADER Frederick W. Braun, General Motors Corporation, corporation of Delaware Dearborn, Mich., assignor to Detroit, Mich., a.

Application January 22, 1940, Serial No. 314,976

5 Claims.

This invention relates to a press unloader and more particularly to a device for automatically unloading metal stampings from a press.

Presses for stamping or drawing sheet metal have proved dangerous instrumentalities and injuries to the operators of these presses occur from time to time. It is the object of this invention to increase the safety of the press operator and obviate some of the dangers inherent in press operation. This object has been achieved by a press uploader of very simple form which automatically unloads the stamping from the press without manual assistance from the operator.

In the drawings:

Fig. 1 is a front elevation of a press showing in the full lines the punch retracted and the press unloader in work removing position, and showing in the dotted lines the punch projected and the press unloader in non-operative position.

Fig. 2 is a vertical section along the line 2-2 of Fig. 1.

Fig. 3 is a partial top elevation of the press unloader viewed along the line 3-3 of Fig. 2.

Referring more particularly to the drawings, there is shown a portion of a press comprising a base member I which supports the lower die 2 and the vertically reciprocable member 3 which supports the punch 4. The stamping is designated 5.

.As illustrated in the dotted lines, Fig. 2, the stamping 5 is positioned in the lower die 2 and as the punch or upper die 4 descends, thereby cutting an opening 6 in stamping 5, the offal I drops through the lower die 2 on to rollers 8 by means of which it is conveyed away. As the reciprocating press member 3 descends, a pair of dogs 9, pivotally mounted as at I on member 3, interengage the edge of the stamping 5. A tension spring I I biases the dogs inwardly. One end of the tension spring I I is connected to member 3 and the other end to dog 9. Thus, as the punch 4 descends the head I3 of the dog 9 rides over and then snaps under the edge of the stamping so that as the punch is retracted or withdrawn upwardly the dogs 9 remove the stamping from the lower die 2. As the punch nears fully raised position, the upper end of the dogs engage cam surfaces I4 of the cam members I5 which are connected to the stationary frame of the press (not shown). The cams I4 tilt the dogs to release the stamping 5 which falls upon the press unloader which will now be described.

The press unloader comprises a pair of inclined -arms I5 which swing about a horizontal axis in the form of pins I1 fixed to the front of the base I. The arms I6 when swung to operative position, Fig. 2, are inclined downwardly and outwardly of the press so that they serve as ramps down which the stampings 5 slide out of the press on to the conveyer I8.

The arms I6 comprise two portions, a ramp I9 down which the stamping slides as itis removed from the press and a supporting arm portion 20 which is connected to the lower end of the ramp I0 and supports the ramp. As shown ramp I9 and arm 20 are formed integrally. Arm 20 is positioned perpendicularly to axis I1 whereas ramp I9 is positioned at an acute angle to axis 4ITI. Thus, as ramp I9 rotates about axis I'I, it describes a portion of the surface of a cone whereas arm 20 describes a sector of a circle. The arms I6 are shown in raised or operative position in the full lines, Figs. l, 2 and3, and in lowered or inoperative position in the dotted lines in the same iigures.

As shown, arm I6 in swinging from operative to inoperative position travels through an arc of about The raising and lowering of the arms I6 is accomplished by means of lever 2| which is fixed to hub 22 of arm 20. Lever 2| is connected by means of link 23 with the reciprocating press member 3. Link 23 is pivotally connected to member 3 as at 24 and to lever 2I as at 25. v

The operation of the device is as follows: When the punch is lowered, dotted line showing in the drawings, levers 23 are swung downwardly thereby swinging arms I6 90 outwardly and downwardly from the press to lowered position. This removes arm I6 from between dies 2 and 4. As the punch raises, link the arms upwardly about horizontal axes I1 to raised position. The work falls upon the ramp portions I9 of the arms I6 and slides downwardly and outwardly of the press on to the conveyor I8. Thus the operation of the press does not require the operator to put his hands into the press between the fixed and movable press members which has heretofore been necessary to remove the work from the press.

The side of the press upon which the arms I6 are pivoted is referred to herein as the discharge side of the press.

I claim:

l. In a press having cooperating dies, a stationary lower die supporting member and a vertically reciprocating upper die supporting member, an unloader for removing the work from the press in the form of a swingable arm pivoted 23 and lever 2I swing on one of the die supporting members, said arm extending at an acute angle to its axis of rotation whereby as the arm swings from operative position between the dies to inoperative position without the dies the arm describes a portion of the surface of a cone, means carried by the upper die supporting member for lifting the work out of the lower die, elevating the work and then dropping the work on the arm when in operative position whereby the work slides down the arm and out of the press, and driving means for said arm synchronized with the upper die supporting member whereby upon upward movement of the supporting member the tween the dies and upon downward movement of the member the arm is vswung from between the dies.

2. In a press having cooperating dies, a lower die supporting member and an upper die supporting member relatively movable upwardly and downwardly toward and away from each other, an unloader for removing the work from the press in the form of a swingable arm mounted on the lower die supporting member, a pivot for the discharge side of the lower die member, said arm comprising a supporting portion pivotally mounted on the said pivot and swingable in a vertical plane and a ramp portion inclined downwardly and outwardly toward the discharge side of the press when `in operative position lower die and dropping 1t upon the ramp when in operative position whereby the work slides by gravity down the ramp and out of the press.

3. In a press having cooperating dies and die relatively movable upwardly and downwardly toward and away from each other, an unloader for removing the work from the press in the form of swingable arms mounted in spaced relation on one of the die support members and swingable toward each other to a position between the dies when separated with the arms inclined downwardly and outwardly from between the die members, means carried by the upper supporting member for withdrawing the work from the lower die member and discharging the same by gravity upon the said arms position between the dies whereby the work slides by gravity down said arms, and driving means for said arm synchronized with said die members whereby the arms are swung from operative position to inoperative position as the supporting members move toward each other and from inoperative to operative position as the supporting members move away from each other.

4. In a press having cooperating dies, a stationary lower die supporting member and a vertically reciprocating upper die supporting member, an unloader for removing the work from the press in the form of swingable arms pivoted in spaced relation on the lower die supporting member, each of said arms extending at an acute angle to its axis of rotation whereby as the arms swing from operative position between the dies to inoperative position without the dies each arm describes a portion of the surface of a cone, means carried by the upper die supporting member for lifting the work out of the lower die, elevating the work and then dropping the work on the arms when in operative position whereby the work slides down the arms and out of the press, and driving means for said arms synchronized with reciprocating die support members whereby upon upward movement of the supporting member the arms are swung between the dies and upon downward movement of the member the arms are swung from between the dies.

5. In a press having cooperating dies and die supporting members relatively movable toward and away from each other, an unloader for removing the work from the press in the form of a pair of arms pivotally mounted in spaced relation on one of said support members, means carried by the upper die supporting member for lifting the work from the lower die and dropping the work on said arms when in operative position, parallel horizontal pivots for said arms whereby said arms swing towards each other about parallel horizontal axes to operative position between the dies, said arms when in operative position being inclined downwardly toward the work discharge side of the press, and driving means for said arms synchronized with said die members whereby the arms are swung away from each other from operative position to inoperative position as the die supporting members move toward each other and are swung toward each other from inoperative to operative position as the supporting members move away from each other.

when in operative FREDERICK W. BRAUN.

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