Abstract: An air-operated percussive tool incorporates apparatus for reducing vibration transmission from a working end portion (1) to a hand grip (2), thereby to reduce vibration transmission to the hand/arm of the user. The apparatus includes a male frustoconical portion (3) whose tip is located facing a female bed (4) with the base of the frustoconical part attached to the handle grip (2) while the bed (4) is attached to the working end portion (1). Three rubber balls (5) are trapped between the portion (3) and bed (4) and the balls (5) are located in their mean positions under compression. Oscillatory movement of the female bed parallel to the longitudinal access of the frustocone causes the balls to roll on the male and female surfaces and effectively provide a rising spring rate or stiffness. Apparatus is also disclosed for reducing vibration transmissions from the working portion to a casing (12) of the tool.

Abstract: An air-operated percussive tool incorporates apparatus for reducing vibration transmission from a working end portion to a hand grip, thereby to reduce vibration transmission to the hand/arm of the user. The apparatus includes a male frustoconical portion whose tip is located facing a female bed with the base of the frustoconical part attached to the handle grip while the bed is attached to the working end portion. Three rubber balls are trapped between the portion and bed and the balls are located in their mean positions under compression. Oscillatory movement of the female bed parallel to the longitudinal access of the frustocone causes the balls to roll on the male and female surfaces and effectively provide a rising spring rate or stiffness. Apparatus is also disclosed for reducing vibration transmissions from the working portion to a casing of the tool.