# US 4,398,409 A · Friction shock assembly for a forging hammer > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 4,398,409 A - Document ID: US4398409A - Status: Granted - Kind: A - Application number: 06/237,497 - Filed: 1981-02-23 - Granted: 1983-08-16 - Earliest claimed: 1981-02-23 - Assignees: National-Standard Company - Inventors: Robert D. Hambrick - Web page: https://patentgrep.com/patent/US4398409A ## CPC - B21J 13/00: Details of machines for forging, pressing, or hammering - B21J 7/24: operated by steam, air, or other gaseous pressure - B21J: FORGING; HAMMERING; PRESSING METAL; RIVETING; FORGE FURNACES (rolling of metal B21B; making particular products by forging or pressing B21K; cladding or plating B23K; finishing surfaces by hammering B23P9/04; compacting surfaces by blasting with particulate material B24C1/10; general features of presses, presses for consolidating scrap B30B; furnaces in general F27) ## Abstract A friction shock absorber comprised of a plurality of mating friction surfaces in constant contact together is incorporated on an oscillating member of the valve shifting mechanism of a forging hammer for preventing the valve from bouncing away from its intended position after it has been shifted by the motion of the forging hammer ram. ## Claims ### Claim 1 A friction shock absorber assembly for use in a forging hammer having a pneumatic powered ram engageable with a shifting valve mechanism having an oscillating rotary shaft for reversing the direction of the ram, the improvement including a friction shock absorber assembly comprised of a plurality of friction members having mating friction surfaces adapted to be mounted and in contact with one another on the oscillating shaft, and wherein the friction members of the friction shock absorber assembly are free of enclosure and maintain a shape under working pressures without the need for an enclosure to prevent distortion of the friction material of said friction members. ### Claim 2 (depends on 1) The friction shock absorber assembly in accordance with claim 1 wherein at least one of said plurality of mating friction surfaces comprises a disc. ### Claim 3 (depends on 1) The friction shock absorber assembly in accordance with claim 1 further including adjustment means for drawing said plurality of mating friction surfaces together to thereby exclude foreign particles from the absorber assembly. ### Claim 4 A friction shock absorber on an oscillating rotary member of a valve shifting mechanism of a forging hammer for preventing the valve portion of the shifting mechanism from movement from its intended position after it has been shifted by the motion of the forging hammer ram wherein said friction shock absorber includes a plurality of friction members having mating friction surfaces in contact with each other thereby excluding foreign particles from entering between said mating friction surfaces, and wherein said friction members of said friction shock absorber are free of enclosure and maintain a shape under working pressures without the need for an enclosure to prevent distortion of the friction material of said friction members. ### Claim 5 (depends on 4) The friction shock absorber in accordance with claim 4 wherein at least one of said plurality of mating friction surfaces comprises a disc. ### Claim 6 (depends on 4) The friction shock absorber in accordance with claim 4 wherein said plurality of said mating friction surfaces are urged together by a spring. ### Claim 7 (depends on 4) The friction shock absorber in accordance with claim 4 further including adjustment means for drawing said plurality of said mating friction surfaces together. ### Claim 8 A friction shock absorber assembly for use in a forging hammer having a pneumatic powered ram engageable with a shifting valve mechanism having an oscillating shaft for reversing the direction of the ram, the improvement including a friction shock absorber assembly comprised of a plurality of friction members having mating friction surfaces mounted on the shaft by a shaft and urged together in contact with one another on the oscillating shaft by a spring. ### Claim 9 A friction shock absorber assembly for use in a forging hammer having a pneumatic powered ram engageable with a shifting valve mechanism having an oscillating shaft for reversing the direction of the ram, the improvement including a friction shock absorber assembly comprised of a plurality of friction members having mating friction surfaces comprised of at least an adjusting ring, first and second splined disc members and a center plate member mounted on the shaft by a shaft and urged together in contact with one another on the oscillating shaft by a spring. ### Claim 10 A friction shock absorber assembly for use in a forging hammer having a pneumatic powered ram engageable with a shifting valve mechanism having an oscillating shaft for reversing the direction of the ram, the improvement including a friction shock absorber assembly comprised of a plurality of friction members having mating friction surfaces comprised of at least an adjusting ring, first and second splined disc members, center plate member and friction discs mounted adjacent to said center plate member mounted on the shaft by a shaft and urged together in contact with one another on the oscillating shaft by a spring.