US3143957A

US3143957A - Guard

Info

Publication number: US3143957A
Application number: US210718A
Authority: US
Inventors: Jr Edward L Cornell
Original assignee: WM H Welsh Co Inc
Current assignee: WM H Welsh Co Inc
Priority date: 1962-07-18
Filing date: 1962-07-18
Publication date: 1964-08-11
Anticipated expiration: 1981-08-11

Description

Aug- 11,1964 E. CORNELL, JR 3,143,957

GUARD Filed July 18, 1962 2 Sheets-Sheet l E. L. CORNELL, JR

Aug. .11, 1964 GUARD 2 Sheets-Sheet 2 Filed July 18, 1962 United States Patent O 3,143,957 GUARD Edward L. Cornell, Ir., Wilmette, Ill., assignor to Wm. H. Welsh Co., Inc., a 'corporation of Illinois Filed July 18, 1962, Ser. No. 210,718 4 Claims. (Cl. 10G- 53) This invention relates to a guard and more particularly to a guard especially adapted for use in connection with a reciprocating machine such asV a press.

It is a general object of the present invention to produce a new and improved guard of the character described.

It is a more particular object of the invention to provide a guard which, when used in conjunction with a reciprocating tool such as a press, serves to arrest movement of the ram of the press in the event the hand or fingers of the press operator, or other obstruction, is present in the line of movement of the ram.

Thus, it is a further object of the present invention to provide a new and improved safety guard for a press.

Other and further objects and advantages of the invention will be readily apparent from the following description and drawings, in which:

FIG. 1 is a front elevational view of a kick press embodying the guard of the present invention;

FIG. 2 is a side elevational view of the apparatus shown in FIG. 1;

FIG. 3 is a view like FIG. l showing the ram in down position;

FIG. 4 is a View like FIG. l showing the position of the parts when the guard encounters an obstruction; and

FIG. 5 is a horizontal sectional view taken along line 5*5 of FIG. 4.

While this invention is susceptible of embodiment in many different forms, there is shown in the drawings and will herein be described in detail a specific embodiment of the invention, with the understanding that the present disclosure is to be considered as an exemplication of the principles of the invention and is not intended to limit the invention to the embodiment illustrated. The scope of the invention will be pointed out in the appended claims.

While it will be readily apparent to those skilled in the art that the guard of the present invention may be utilized as a safety device in association with a number of tools, it is particularly adapted for use in connection with a press of the reciprocating ram type such as, for example, a kick press, and the specific embodiment of the invention chosen for illustration is one incorporated in such a press.

Thus, there is shown in the drawings a kick press having lixed frame 11 in which a ram 12 is mounted for vertical reciprocation toward and away from a work piece 13. The xed frame carries a plate 15 provided with spaced vertical guideways 16 in which guide rods 17 are slidable. The upper ends of the guide rods are connected together by a crossbar 18 and carry at their lower ends an arcuate feeler 19.

The feeler is intended to be reciprocated in timed relationship with the reciprocation of the ram but for the purposes of the present invention, must proceed toward the work piece, and hence toward any obstruction intervening between the ram and the work piece, at a speed greater than the speed of approach of the ram. For this purpose there is provided an arm 20 pivotally secured to the plate 15 and carrying an upper roller 21 bearing against the underside of the crossbar 18. The arm 20 also carries an intermediate roller 22 which bears against the upper surface 23 of a block 24 carried by the ram 12.

When the ram is in the upper position shown in FIG. l, the feeler 19 is raised well above the Work piece, but as the ram proceeds downwardly to the position shown in FIG. 3, surface 23 of the block 24 will have moved out from under the roller 22 allowing the feeler 19 to move by gravity toward the work piece well in advance of the ram.

The block 24 is provided with a shoulder 25 which is positioned to cooperate with a stop 26,pivoted at 27 to the fixed frame. The stop is provided with a cam vsurface 28 adapted to cooperate with a cam follower 29 secured to the right-hand guide rod 17.

The stop 26 is held in a position located in the path of movement of the shoulder 25 by the follower 29 and unless moved by such follower out of the path as hereinafter described, would serve to arrest further downward movement of the ram when brought into engagement with the shoulder 25. In the event no obstruction exists in the path of movement of the feeler 19, it continues its downward movement until the follower 29 contacts the cam surface 28, pivoting the stop 26 to the position shown in FIG. 3 out of the path of movement of the shoulder 25. If, on the other hand, the feeler encounters an obstruction such as the ones illustrated in FIGS. 4 and 5, further downward movement of the guide rods 17 is prevented and hence the carn follower 29 does not reach the cam 28 to pivot the stop out of the path of movement of the shoulder on the block 24. Downward movement of the ram is thereby arrested when the shoulder encounters the stop 26.

The position of the feeler 19 may be adjusted through the adjusting means indicated at 30 to accommodate changes in the size of the ram head or work piece.

From the foregoing, it can be seen that the guard of the present invention is of relatively simple construction and yet provides an excellent safety measure for use in reciprocating presses of the type illustrated. Being of simple construction, there are but a few operating parts and hence the positive functioning of the guard is assured.

I claim:

l. In a press having a ram adapted to be reciprocated toward and away from a work piece, a guard comprising a stop for arresting movement of the ram toward the work piece, means for normally maintaining said stop in movement-arresting position, means for moving the stop to a non-arresting position, a feeler movable toward the work piece in advance of the ram along a path outside the path of reciprocation of the ram, and means associated with the feeler for moving the stop to non-arresting position when the feeler nears the end of its movement toward the work piece.

2. In combination with a press having a fixed frame and a ram reciprocably mounted in the frame for movement toward and away from a work piece, guard means comprising, means secured to the frame and providing vertical guideways on either side of the ram, a pair of vertically extending guide rods slidably mounted in the guideways, a horizontal crossbar secured to the upper ends of the guide rods, a feeler secured to and extending between the lower ends of the guide rods, a block having a generally horizontal upper surface secured to the ram, said block having a shoulder formed on one side thereof, an arm having one end pivotally secured to the fixed frame and carrying a roller at its other end, said roller engaging the lower surface of the crossbar, a second roller carried by said arm intermediate the ends thereof and engaging said horizontal upper surface of the block whereby movement of the ram toward its upper position brings the upper surface of the block into contact with said secin said arresting position, a cam surface formed on said stop and a cam follower carried by one of said guide rods to engage said cam surface and pivot the stop to nonarresting position when the feeler reaches the lower portion of its movement.

3. In a press having a ram reciprocably mounted in a frame and including means for reciprocating the ram toward and away from a work piece, a guard comprising, a stop for arresting movement of the ram toward the work piece, means for normally maintaining said stop in movement-arresting position, a feeler movable with the rarn toward and away from the work piece along a path outside the path of reeiprocation of the ram, an arm pivoted only at one end to the frame, means carried by the ram and adapted to pivot the arm with movement of the ram, the free end of said arm engaging said feeler to move the same toward and away from the work piece in advance of the ram, and means movable with the feeler for moving the stop to non-arresting position when the feeler nears the end of its movement toward the work piece.

4. In a press having a ram reciprocably mounted in a frame and including means for reciprocating the ram toward and away from a work piece, a guard comprising, a stop pivotally mounted on the frame for arresting movement of the ram toward the work piece, means for normally maintaining said stop in movement-arresting position, a feeler movable toward and away from the work piece along a path outside the path of reciprocation of the ram, an arm pivoted only at one end to the frame, means carried by the ram for pivoting the arm with movement of the ram, the free end of said arm engaging said feeler to move the same toward and away from the work piece with the movement toward the work piece being in advance of the ram, and means movable with the feeler for pivoting the stop to non-arresting position when the feeler nears the end of its movement toward the work piece.

References Cited in the le of this patent UNITED STATES PATENTS 1,102,509 Hoelemann July 7, 1914 1,860,991 Carroll et al May 31, 1932 2,049,990 Armstrong Aug. 4, 1936 2,531,837 Beebe Nov. 28, 1950 FOREIGN PATENTS 572,348 France Oct. 3, 1945 654,952 Great Britain July 4, 1951 859,638 France June 10, 1940 1,118,669 Germany Nov. 30, 1961

Claims

1. IN A PRESS HAVING A RAM ADAPTED TO BE RECIPROCATED TOWARD AND AWAY FROM A WORK PIECE, A GUARD COMPRISING A STOP FOR ARRESTING MOVEMENT OF THE RAM TOWARD THE WORK PIECE, MEANS FOR NORMALLY MAINTAINING SAID STOP IN MOVEMENT-ARRESTING POSITION, MEANS FOR MOVING THE STOP TO A NON-ARRESTING POSITION, A FEELER MOVABLE TOWARD THE WORK PIECE IN ADVANCE OF THE RAM ALONG A PATH OUTSIDE THE PATH OF RECIPROCATION OF THE RAM, AND MEANS ASSOCIATED WITH