Hardware press and punch apparatus

• US 4,391,358 A
• Filed: 11/05/1980
• Issued: 07/05/1983
• Est. Priority Date: 11/05/1980
• Status: Expired due to Term

• Current Assignee: Virgil J. Haeger
• Original Assignee: Virgil J. Haeger
• Inventors: Haeger, Virgil J.
• Primary Examiner(s): Crane, Daniel C.
• Application Number:
  US06/204,200
• Time in Patent Office: 972 Days
• Field of Search: 29/708, 72/1, 192/129 A, 192/134, 192/130, 200/61.42
• US Class Current: 192/130
• CPC Class Codes: B21D 55/00 Safety devices protecting the machine or the operator, specially adapted for apparatus or machines dealt with in this subclass for presses in general B30B; safety devices in general F16P
• CPC Class Codes: B21J 15/28 Control devices specially adapted to riveting machines not restricted to one of the preceding subgroups
• CPC Class Codes: F16P 3/16 with feeling members moved by the machine
• CPC Class Codes: Y10T 29/53035 Responsive to operative [e.g., safety device, etc.]

Abstract

Presented is a hardware punch and/or press apparatus adapted to assemble fastening devices to or punch holes in hardware for various purposes. The apparatus includes a stationary tool or anvil on which hardware on which an operation is to be performed is supported, and a hydraulically operated ram adapted to move against the work piece or hardware upon activation of an appropriate switch. In one aspect of the invention, a mechanism is provided to effect retraction of the hydraulically operated ram without the imposition of a destructive pressure if the operator'"'"'s finger is contacted by the ram.

Claims

1. A hardware press for assembling fastenening devices or punching holes in sheetmetal hardware devices and incorporating safety provisions to prevent injury to the operator, comprising:

(a) a base structure;

(b) a pedestal assembly on the base structure and including a cantilever arm portion projecting laterally therefrom;

(c) a pressure-exerting ram assembly mounted on said cantilever arm adjacent the free end thereof and including a hydraulic cylinder and a double-acting ram operatively associated therewith and selectively movable through a predetermined excursion along its longitudinal axis, said ram assembly being electrically insulated from said cantilever arm on which it is mounted;

(d) an anvil mounted on said pedestal and underlying said ram assembly;

(e) an upper tool holder slidably mounted on said ram in electrically conductive interrelation therewith and adapted to removably support a selected upper tool thereon;

(f) a lower tool holder mounted on said anvil in electrically conductive interrelation therewith and adapted to removably support a selected lower tool thereon in cooperative relation to said upper tool; and

(g) control means for normally selectively advancing said ram under a predetermined high hydraulic pressure to bring said upper and lower tools together into a predetermined pressure exerting relationship upon a workpiece interposed therebetween with a pressure injurious to the operator if imposed on the operator'"'"'s hand while automatically stopping advance of the ram if the operator'"'"'s hand is encountered between the upper and lower tool holders;

(h) said control means including a normally-open safety switch operatively interposed between said ram and said upper tool holder and operable to close a circuit to stop the advance of the ram when a non-conductive element, such as the operator'"'"'s hand, is encountered with sufficient force to slidably displace said upper tool holder to close said normally-open switch.

2. The combination according to claim 1, in which said control means includes a double-pole, double throw conductive/non-conductive mode selector switch manipulable to condition the control means in relation to whether the workpiece is electrically conductive or non-conductive, and a ram-actuating switch which must be depressed twice to impose said predetermined operating pressure upon a non-conductive workpiece.

3. The combination according to claim 1, in which said control means includes a hydraulic circuit and an electrical circuit, said hydraulic circuit including a hydraulic pump actualble to selectively pressurize said pressure-exerting ram assembly and an electrically operated valve for controlling the flow of hydraulic fluid through said circuit, said electrical circuit including solenoids associated with said valve for controlling the flow of hydraulic fluid, and a plurality of interconnected relays operable to control the retraction of the pressure-exerting ram when an operator'"'"'s hand is encountered between the upper and lower tools.

4. The combination according to claim 1, in which said control means includes a ground potential circuit of which the upper and lower tool holders form an electrically conductive part.

5. The combination according to claim 1, in which said control circuit includes said upper and lower tools as the terminal of a grounding circuit which is completed when a conductive workpiece is interposed therebetween thus enabling the ram to advance in a pressure-exerting mode and which is not completed when a non-conductive element such as the operator'"'"'s hand is interposed between the upper and lower tool holders, thus stopping the advance of the ram before an injurious pressure is exerted thereby.

6. The combination according to claim 1, in which said control means includes an electrical circuit and a hydraulic circuit, said electrical circuit including a foot-operated double-pole, double-throw switch which when actuated in one mode effects advancement of the ram and when actuated in the opposite mode effects retraction of the ram, a relay timer energized when said foot-operated switch is actuated in a ram-down mode to effect elevation of the ram upon completion of a cycle, and a reostat for controlling the relay timer to determine the degree of elevation of said ram.

7. A hardware press for assembling fastenening devices or punching holes in sheetmetal hardware devices and incorporating safety provisions to prevent injury to the operator, comprising:

(a) a base structure;

(b) a pedestal assembly on the base structure and including a cantilever arm portion projecting laterally therefrom;

(c) a pressure-exerting ram assembly mounted on said cantilever arm adjacent the free end thereof and including a hydraulic cylinder and a double-acting ram operatively associated therewith and selectively movable through a predetermined excursion along its longitudinal axis, said ram assembly being electrically insulated from said cantilever arm on which it is mounted;

(d) an anvil mounted on said pedestal and underlying said ram assembly;

(e) an upper tool holder slidably mounted on said ram in electrically conductive interrelation therewith and adapted to removably support a selected upper tool thereon;

(f) a lower tool holder mounted on said anvil in electrically conductive interrelation therewith and adapted to removably support a selected lower tool thereon in cooperative relation to said upper tool; and

(g) control means for normally selectively advancing said ram under a predetermined high hydraulic pressure to bring said upper and lower tool together into a predetermined pressure exerting relationship upon a workpiece interposed therebetween with a pressure injurious to the operator if imposed on the operator'"'"'s hand while automatically stopping advance of the ram if the operator'"'"'s hand is encountered between the upper and lower tool holders;

(h) said control means including a normally-open safety switch interposed between said ram and said upper tool holder and adapted to be closed to complete an electrical circuit if an operator'"'"'s hand or other electrically non-conductive element is disposed between the upper and lower tools, and a pressure-actuated control switch actuated by hydraulic pressure and including normally-open terminals adapted to be closed to make a circuit to effect elevation of the ram.