Abstract: A dust-collecting device for collecting cutting chips produced by a cutting device has a separator for separating the cutting chips from the carrier air by utilizing the force of gravity upon the cutting chips. A dust container collects the cutting chips separated by the separator. The separator includes a separator body having a cutting chip discharge pipe and an air discharge pipe. After separation the carrier air is discharged upward from the separator body via the air discharge pipe. The separated cutting chips are discharge downward from the separator body via the cutting chip discharge pipe. The dust container is connected to the cutting chip discharge pipe.

Abstract: It is an object of the invention to provide an effective technique for avoiding the influence of reaction during tightening operation in the rotary fastening tool.

Abstract: Tightening tools is provided with a pair of clutch members disposed between a motor and a tool bit. The pair of clutch members is provided with a first engaging portion and a second engaging portion. The first engaging portion is constructed so as to disengage the pair of clutch members when the torque applied to the tool bit is equal to or above a first predetermined value. The second engaging portion does not engage the pair of clutch members while the first engaging portion engages the pair of clutch members and the second engaging portion engages the pair of clutch members after the first engaging portion disengages the pair of clutch members. The second engaging portion is constructed so as to disengage the pair of clutch members when the torque applied to the tool bit is equal to or above a second predetermined value. The second predetermined value may be different from the first predetermined value.

Abstract: A dust-collecting device for collecting cutting chips produced by a cutting device has a separator for separating the cutting chips from the carrier air by utilizing the force of gravity upon the cutting chips. A dust container collects the cutting chips separated by the separator. The separator includes a separator body having a cutting chip discharge pipe and an air discharge pipe. After separation the carrier air is discharged upward from the separator body via the air discharge pipe. The separated cutting chips are discharge downward from the separator body via the cutting chip discharge pipe. The dust container is connected to the cutting chip discharge pipe.

Abstract: Power tool (11) may include a motor and oil pulse unit (22) that generates an elevated torque. Oil pulse unit (22) may be coupled to the motor and have output shaft (18). When load acting on output shaft (18) is less than a predetermined value, rotating torque generated by the motor is directly transmitted to output shaft (18). When the load acting on output shaft (22) exceeds the predetermined value, an elevated torque is generated by oil pulse unit (22) and applied to output shaft (18). Output shaft (18) may be connected to load shaft (12). A socket may be attached to the distal end of load shaft (12). Power tool (11) may further include detecting device (20) for detecting change in rotational angle of output shaft (18) and the direction of rotation thereof, and a control device. The detecting device (20) may output signals corresponding to a state of output shaft (18) to the control device. The control device may store the state of output shaft (18) at predetermined interval.

Abstract: Power tool (11) may include a motor and oil pulse unit (22) that generates an elevated torque. Oil pulse unit (22) may be coupled to the motor and have output shaft (18). When load acting on output shaft (18) is less than a predetermined value, rotating torque generated by the motor is directly transmitted to output shaft (18). When the load acting on output shaft (22) exceeds the predetermined value, an elevated torque is generated by oil pulse unit (22) and applied to output shaft (18). Output shaft (18) may be connected to load shaft (12). A socket may be attached to the distal end of load shaft (12). Power tool (11) may further include detecting device (20) for detecting change in rotational angle of output shaft (18) and the direction of rotation thereof, and a control device. The detecting device (20) may output signals corresponding to a state of output shaft (18) to the control device. The control device may store the state of output shaft (18) at predetermined interval.

Abstract: A hydraulic unit includes a case, a liner contained in the case, and a top cap and an opposing bottom cap plugged at the front and rear ends of the case. The unit further includes a spindle disposed in the liner and provided with a large diameter section. The large diameter section has a pair of blades with one having longer first pins and the other having shorter second pins on their front and rear end surfaces. A first oblong cam recess and a second oblong cam recess having a longer longitudinal axis and a shallower depth than the first recess are formed in the opposing inner surfaces of the bottom cap and the top cap. During rotation of the case, the cam recesses guide the first and second pins on the blades while preventing the blades from sliding on second sealing surfaces of the liner, which are associated with ribs on the spindle.

Abstract: A hydraulic unit (1) includes a case (2) having an axially slidable top cap (11) at the rear end thereof The hydraulic unit further includes a spindle (17) having communicating holes (28) axially formed therein and a column (19) which is inserted into the case. The column of the spindle includes a through-hole (29) formed therein and is rotatably supported by the top cap's closed-end hole (15). A pair of fluid chambers (25) and another pair of fluid chambers (26) are defined between the case and the spindle. The communicating holes (28) are capable of placing the fluid chambers (25) in communication with a bottom surface (16) of the closed-end hole (15) via the through-hole (29) when the fluid pressure in the fluid chambers (25) reaches or exceeds a threshold.

Abstract: A hydraulic unit includes a case, a liner contained in the case, and a top cap and an opposing bottom cap plugged at the front and rear ends of the case. The unit further includes a spindle disposed in the liner and provided with a large diameter section. The large diameter section has a pair of blades with one having longer first pins and the other having shorter second pins on their front and rear end surfaces. A first oblong cam recess and a second oblong cam recess having a longer longitudinal axis and a shallower depth than the first recess are formed in the opposing inner surfaces of the bottom cap and the top cap. During rotation of the case, the cam recesses guide the first and second pins on the blades while preventing the blades from sliding on second sealing surfaces of the liner, which are associated with ribs on the spindle.

Abstract: A hydraulic unit (1) includes a case (2) having an axially slidable top cap (11) at the rear end thereof. The hydraulic unit further includes a spindle (17) having communicating holes (28) axially formed therein and a column (19) which is inserted into the case. The column of the spindle includes a through-hole (29) formed therein and is rotatably supported by the top cap's closed-end hole (15). A pair of fluid chambers (25) and another pair of fluid chambers (26) are defined between the case and the spindle. The communicating holes (28) are capable of placing the fluid chambers (25) in communication with a bottom surface (16) of the closed-end hole (15) via the through-hole (29) when the fluid pressure in the fluid chambers (25) reaches or exceeds a threshold.

Abstract: In a hydraulic impulse screwdriver (1), a hammer (13) includes axial grooves (14) formed in the inner side wall thereof, and a spindle (11) includes V-shaped cam grooves (15) formed in the outer side wall thereof. A plurality of balls (16) are disposed in the space between the axial grooves and the opposing cam grooves. The screwdriver additionally includes a coil spring (17) for biasing the hammer (13) in a forward direction. The hammer is coupled to an anvil (19) by means of engaging recesses (18) of the hammer and engaging teeth (21) of the anvil so as to rotate integrally with the anvil. The anvil is firmly connected to a main body (24) of a hydraulic unit (23).