Abstract: There is disclosed a tool (5) comprising a cam track (A) and cam follower means (B), wherein a width (WA) of at least a portion of the cam track (A) is greater than a width (WB) of the cam follower means (B). The cam follower means (B) is engaged within the cam track (A), the cam follower means (B) being adapted to run in/around the cam track (A) and be thrown between opposing walls (D, E) of the cam track (A). In use, the cam follower means (B) therefore has two degrees of motion, a first defined by the cam track (A), and a second defined by ricochet between opposing walls (D, E).

Abstract: The invention provides a portable power tool which is lightweight and convenient to use by the general public in any of its various forms, as a wallpaper stripper, a paint scraper or a cold chisel up to a power spade. The tool comprises a housing (12), a drive, an electric motor (14,160) adapted to drive at least one selected tool bit (4,56,62,64,66,68) mounted on an output shaft (44) moving in a reciprocating axial manner. Conveniently the drive may be a linear motor (160) or if used with a cam device, a rotary motor (14). The cam device may be a cylinder cam (32) provided with a sinusoidal cam track (34).

Abstract: The invention relates to portable power tool intended to form part of a power tool or a conversion unit adpated to be fitted to the shaft of a power tool. The tool includes a rotary cam member (6, 8) having an internal sinusoidal cam track (12) in which cam followers (26) of an output shaft (2) are received. When the cam member (6, 8) rotates, the shaft (2) is caused to partake of a lengthwise reciprocating movement suitable for application to a scraper bit or other tool kit such as a chisel. In an example of the invention, the shaft (86) passes through a fixed bearing ring (88), a slidable sleeve (96) being provided to control engagement of the shaft (86) via a key member (104) with portions of the ring (88) or the cam member (76), so as to enable the shaft (86) to partake of lengthwise movement or to be convertible to rotational movement, as selected by the operator.

Abstract: The invention provides a portable power tool which is lightweight and convenient to use by the general public in any of its various forms, as a wallpaper stripper, a paint scraper or a cold chisel up to a power spade. The tool comprises a housing (12), a drive means, conveniently an electric motor (14,160) adapted to drive a selected tool bit (4,56,62,64,66,68), the output shaft (44) moving in a reciprocating axial movement. Conveniently the drive means may be a linear motor (160) or if used with a cam device, a rotary motor (14). The cam device may be a cylinder cam (32) provided with a sinusoidal cam track (34).