Abstract: A power tool comprises a housing having at least two housing parts and at least one recess, a portion of the recess provided by each housing part, and a bearing located in the recess. The power tool includes a seal comprising an elongate seal member located between the housing parts to seal at least a portion of the housing. The seal includes at least one polymeric extension part extending from the elongate seal member and in contact with an external part of the bearing without extending around the bearing. The polymeric extension part of the seal prevents the external part of the bearing from rotating with respect to the housing during use of the power tool.

Abstract: A hammer drill comprises a motor including an output shaft, a shaft assembly rotationally engaged therewith, a hollow spindle, and a hammer mechanism comprising a piston arranged for reciprocating motion within the spindle. The shaft assembly comprises a first part carrying a first gear engaged with a gear on the spindle to cause spindle rotation, a second part carrying a crank member to cause piston reciprocation, and a connecting part configured to rotationally interconnect, or disconnect, the first and second parts. In a first position of the connecting part only one of the first and second parts is rotationally engaged with the output shaft to enable rotation of only one of the first gear and the crank member respectively, while in a second position both the first and second parts are rotationally engaged with the output shaft to enable rotation of both the first gear and the crank member.

Abstract: A hammer drill comprises a motor including an output shaft, a shaft assembly rotationally engaged therewith, a hollow spindle, and a hammer mechanism comprising a piston arranged for reciprocating motion within the spindle. The shaft assembly comprises a first part carrying a first gear engaged with a gear on the spindle to cause spindle rotation, a second part carrying a crank member to cause piston reciprocation, and a connecting part configured to rotationally interconnect, or disconnect, the first and second parts. In a first position of the connecting part only one of the first and second parts is rotationally engaged with the output shaft to enable rotation of only one of the first gear and the crank member respectively, while in a second position both the first and second parts are rotationally engaged with the output shaft to enable rotation of both the first gear and the crank member.

Abstract: A power tool comprises a housing having at least two housing parts and at least one recess, a portion of the recess provided by each housing part, and a bearing located in the recess. The power tool includes a seal comprising an elongate seal member located between the housing parts to seal at least a portion of the housing. The seal includes at least one polymeric extension part extending from the elongate seal member and in contact with an external part of the bearing without extending around the bearing. The polymeric extension part of the seal prevents the external part of the bearing from rotating with respect to the housing during use of the power tool.

Abstract: A method of assembling a hand held electrically powered drilling and/or hammering tool having a tool housing and a drilling and/or hammering spindle mounted within the housing. The spindle has a forward end at which a tool or bit may be mounted. The method of assembly includes the steps of making a motor sub-assembly including a motor and a radial fan, the fan has a plurality of blades located on one side of the fan and non-rotatably mounting the fan on an end of the armature shaft of the motor at a first end of the motor with the blades facing away from the armature of the motor. The method further including balancing the motor sub-assembly, and mounting the sub-assembly within the housing, with the longitudinal axis of the motor armature shaft at an angle, preferably perpendicular to the longitudinal axis of the spindle and with the first end of the motor closest to the spindle axis.

Abstract: A switch assembly for a power tool including a switch member and a fixing part. The switch member including a finger grip part, a retaining part for retaining the switch member on a power tool, and an opening extending at least partially through the switch member, the retaining part arranged to project laterally with respect to an axis of the opening. The fixing part is arranged to be located in the opening. The switch assembly is arranged such that when the fixing part is at a first location in the opening, the retaining part adopts a retention configuration in which it projects laterally to a predetermined extent. When the fixing part is removed or at a second location in the opening, the retaining part adopts an insertion configuration in which it does not project laterally or projects less than the predetermined extent.

Abstract: A switch assembly for a power tool comprises a switch member and a fixing part. The switch member comprises a finger grip part, a retaining part for retaining the switch member on a power tool, and an opening extending at least partially through the switch member, the retaining part arranged to project laterally with respect to an axis of the opening. The fixing part is arranged to be located in the opening. The switch assembly is arranged such that when the fixing part is at a first location in the opening, the retaining part adopts a retention configuration in which it projects laterally to a predetermined extent. When the fixing part is removed or at a second location in the opening, the retaining part adopts an insertion configuration in which it does not project laterally or projects less than the predetermined extent.

Abstract: A method of assembling a hand held electrically powered drilling and/or hammering tool having a tool housing and a drilling and/or hammering spindle mounted within the housing, which spindle has a forward end at which a tool or bit may be mounted; comprising the steps of making a motor sub-assembly including a motor (4) and a radial fan (2), the fan having a plurality of blades (16) located on one side of the fan and non-rotatably mounting the fan on an end of the armature shaft of the motor at a first end of the motor with the blades (16) facing away from the armature of the motor. Then balancing the motor sub-assembly. Then mounting the sub-assembly within the housing, with the longitudinal axis of the motor armature shaft at an angle, preferably perpendicular to the longitudinal axis (3) of the spindle and with the first end of the motor closest to the spindle axis (3).

Abstract: A reciprocating drive mechanism for a striker in a hammer, a rotary hammer, or a power drill having a hammer action, includes a sinusoidal cam channel formed on a drive member and a cam follower, in the form of a ball bearing, attached to a driven member which, due to the interaction of the cam and cam follower, results in a reciprocating movement of the driven member. Both the drive member and driven member can be rotatingly driven by a motor, their relative speeds resulting in the reciprocating movement of the driven member. The driven member is connected to the striker either via a mechanical helical spring or an air spring.

Abstract: A hand held electrically powered drilling and/or hammering tool comprises a balanced motor sub-assembly including a radial fan mounted to the armature shaft at a first end of the motor with the fan blades facing away from the motor, and motor the sub-assembly is mounted with the axis of the motor angled with respect to the axis of the tool spindle and with the first end of the motor closest to the spindle, and an air outlet is located in the housing near a second end of the motor, and the above components are arranged so that rotation of the fan draws air into its inlet via air inlets and then pushes air from its outlet through the motor and out of the air outlets in the region of the second end of the motor which is remote from the spindle axis.

Abstract: The patent covers a reciprocating drive mechanism for a striker in a hammer, a rotary hammer, or a power drill having a hammer action, which utilise a sinusoidal cam channel formed on a drive member and a cam follower, in the form of a ball bearing, attached to a driven member which, due to the interaction of the cam and cam follower, results in a reciprocating movement of the driven member. Both the drive member and driven member can be rotatingly driven by a motor, their relative speeds resulting in the reciprocating movement of the driven member. The driven member is connected to the striker either via a mechanical helical spring or an air spring.

Abstract: An electrically powered tool having a dust collection unit powered by a motor, which unit can be releasably fitted to the tool includes a plug arrangement and a cooperating socket arrangement, one of which is formed on the tool and the other of which is formed on the unit. A first mechanical fixing arrangement is provided comprising a first projection and a first cooperating recess, one of which is formed on the tool and the other of which is formed on the unit. A second mechanical fixing arrangement is provided and comprises a manually actuable releasable latch arrangement and a second cooperating recess, one of which is formed on the tool and the other of which is formed on the unit. The first and second mechanical fixing arrangements cooperate to secure the dust collection unit to the tool in such a way that the plug and socket arrangements form an electrical connection.

Abstract: A dust extraction shroud for a drill, which surrounds a drill bit and which lies adjacent the work surface, comprises a body portion defining a first inlet adapted to engage the work surface and to surround the location at which said bit penetrates the surface. The shroud body further defines a first outlet connected to a source of suction and a third inlet for allowing the bit to pass through said body portion. A first sealing means is arranged in said third inlet for surrounding said bit and resisting the flow of air. Wherein said body portion includes at least one protruding portion defining a second inlet between said protruding portion and an adjacent part of said body, and on a side of said protruding portion remote from the first inlet. The second inlet admits air to enter said body portion and travel to the first outlet.

Abstract: An electrically powered hand held drilling and/or hammering tool having a dust collection unit powered by a motor (51) housed in the unit, which unit can be releasably fitted to the tool. A plug arrangement (12) and a cooperating socket arrangement (28), one of which is formed on the tool and the other of which is formed on the unit, are provided for electrically connecting the power supply for the tool to the motor (51) of the unit. A first mechanical fixing arrangement is provided comprising a first projection (8) and a first cooperating recess (54), one of which is formed on the tool and the other of which is formed on the unit, located adjacent the respective part of the plug and socket arrangements and a second mechanical fixing arrangement is provided, located remotely from the first and comprising a manually actuable releasable latch arrangement (72,66) and a second cooperating recess (60), one of which is formed on the tool and the other of which is formed on the unit.

Abstract: A method of assembling a hand held electrically powered drilling and/or hammering tool having a tool housing and a drilling and/or hammering spindle mounted within the housing, which spindle has a forward end at which a tool or bit may be mounted; comprising the steps of making a motor sub-assembly including a motor (4) and a radial fan (2), the fan having a plurality of blades (16) located on one side of the fan and non-rotatably mounting the fan on an end of the armature shaft of the motor at a first end of the motor with the blades (16) facing away from the armature of the motor. Then balancing the motor sub-assembly. Then mounting the sub-assembly within the housing, with the longitudinal axis of the motor armature shaft at an angle, preferably perpendicular to the longitudinal axis (3) of the spindle and with the first end of the motor closest to the spindle axis (3).

Abstract: A dust extraction shroud for a drill, which surrounds a drill bit and which lies adjacent the work surface, comprises a body portion defining a first inlet adapted to engage the work surface and to surround the location at which said bit penetrates the surface. The shroud body further defines a first outlet connected to a source of suction and a third inlet for allowing the bit to pass through said body portion. A first sealing means is arranged in said third inlet for surrounding said bit and resisting the flow of air. Wherein said body portion includes at least one protruding portion defining a second inlet between said protruding portion and an adjacent part of said body, and on a side of said protruding portion remote from the first inlet. The second inlet admits air to enter said body portion and travel to the first outlet.

Abstract: A hand-operated electric tool, especially a jigsaw, has a motor unit provided in the tool housing. The motor unit contains in a motor housing the stator and the rotor. One end of the rotor shaft projects from the motor housing and is mounted in two bearings fixed in the motor housing. A countershaft forms an extension of the rotor shaft and carries a toothed arrangement. The countershaft is coupled to the rotor shaft and is rotatably mounted in a bearing. The rotor shaft and countershaft engage axially with radial play and are coupled non-rotatably by co-operating radial projections and recesses receiving the projections. In the region of the overlapping portions of rotor shaft and countershaft, one of the shafts has an annular portion extending at least over a part of the circumference. The annular portion is substantially in line contact with an adjacent circumferential surface of the other shaft. The line contact permits misalignment of the rotor shaft and countershaft but reduces noise.

Abstract: A power saw has two oppositely reciprocating saw blades guided and supported in a receiving slot in a support plate. The blades are supported during sawing along shoulders on their outside by lower edges of support sections of the support plate. The arrangement is such that forces generated in operation during cutting press the saw blades together in the area of their teeth. This prevents saw dust, chippings etc. penetrating between the two saw blades. Preferably, the thickness of the saw blade shoulders are not greater than half the thickness of the saw blades, and preferably no greater than the thickness of the support section edges. The teeth of the saw blades may be so ground and arranged that the resultant force on the teeth during cutting also forces the saw blades together at their teeth.

Abstract: A power saw has two oppositely reciprocating saw blades guided and supported in a receiving slot in a support plate. The blades are supported during sawing along shoulders on their outside by lower edges of support sections of the support plate. The arrangement is such that forces generated in operation during cutting press the saw blades together in the area of their teeth. This prevents saw dust, chippings etc. penetrating between the two saw blades. Preferably, the thickness of the saw blade shoulders are not greater than half the thickness of the saw blades, and preferably no greater than the thickness of the support section edges. The teeth of the saw blades may be so ground and arranged that the resultant force on the teeth during cutting also forces the saw blades together at their teeth.

Abstract: A saw blade, for a power saw having two such blades arranged adjacent and parallel to each other and reciprocating in opposite directions, comprises an elongate blade member having teeth along a bottom edge. The teeth comprise at least three types, a first type being at an outer surface of the blade member, a third type being at the inner surface, and the second type being therebetween. The first type are shaped to produce on the blade's bottom edge an outward force away from the inner surface while cutting a workpiece, and the second and third types are shaped to produce on the blade's bottom edge an inward force, the resultant force on the teeth while cutting urging the teeth in an inward direction away from the outer surface towards the inner surface. When the power saw is operating with a pair of these blades, the blades are urged together at their teeth by the cutting action so effectively eliminating penetration of sawdust and cuttings between the pair of blades.