Abstract: When a start SW 3 is pressed, a one-shot multivibrator circuit 15 turns on and releases a pulse. The pulse is transmitted to a self-hold circuit 16 which in turn stays in self-hold mode and releases an H level output continuously until it is reset. This cause a transistor 17 to turn on and actuate a ram downward movement relay R1. When the ram arrives at the lower limit of its movement, a lower LS 4 is opened causing a self-hold circuit 21 to produce an H level signal in accordance with an output of a one-shot multivibrator 18. The H level signal from the self-hold circuit 21 is delayed by a delay circuit 22 and turns on a transistor 23. As the result, a ram upward movement relay R2 is actuated. Because of the function of the one-shot multivibrator circuit 15, the ram will not restart when the start SW 3 is continuously depressed. The delay circuit 22 contributes to the longer operational life of a directional valve switching mechanism.

Abstract: A coupling disposed in a pneumatic hammer and for removably connecting a spray can to a plug body for connecting a fluid conduit is provided. The coupling is provided with a socket body having a first end portion, a second end portion and an axial hole open in the first and second end portions, a locking mechanism provided in the first end portion end of the socket body and releasably locking and engaging with the plug body, and a mounting member attached to the second end portion of the socket body in such a manner as to freely slide to an axial direction. The mounting member attaches the socket body to the spray can in a removable manner.

Abstract: This invention provides a forming method capable of forming tapered through holes at once with a single pressing operation. A hole is formed in a work with a piercing punch 1 mounted on a press by using a small-diameter punching portion 1a formed on the distal end of the punch 1. A hole 11 formed at this time has a section with an open lower end portion by pressing. By using this hole 11 as a guide, a tapering portion 1b having a diameter slightly larger than the diameter of this hole and a tapered surface T forms a tapered surface on the inner surface of the hole 11 in accordance with plastic working. A "burr 3a" is formed on the edge of the hole 11 by this plastic working. Formation of this "burr 3a" is prevented with a pressure portion 1c formed on the piercing punch 1. When the above process is performed in a single pressing operation, a plurality of tapered through holes can be formed easily.

Abstract: An oscillation switch consists of a pair of ring-shaped electrodes each having an inner surface coaxially provided with a projection and spaced apart at a predetermined distance, and balls arranged in a space formed between the electrodes so that the balls engage the projections to electrically connect the electrodes together when oscillation or lateral sliding occur. A portable electrically driven machine provided with the oscillation switch has the oscillation switch provided on a frame and has a structure which stops a tool rotating motor and a feed motor by interrupting the electric power supply to a control unit of the electric tool. The use of the oscillation switch allows the tool rotating motor or the feed motor to stop as soon as lateral sliding or oscillation starts to occur or when the portable electrically driven machine starts to fall down even if the portable electrically driven tool takes any posture.

Abstract: A pipe connector comprises sockets each having a rear cylindrical member connected to an associated one of first pipes, plugs each having a plug body connected to an associated one of the second pipes, and a locking mechanism, provided on each socket, for locking the associated plug. The pipe connector further comprises an inner cylindrical member having a plurality of housing sections for housing the rear cylindrical members, and a coupling portion for coupling the housing sections, and a main cylindrical member, extending in the axial direction of the housing sections, for movably containing the housing sections. The coupling portion and the main cylindrical member have a pair of holes formed to correspond to each other, one of the pair of holes having a tapered surface inclined with respect to the axial direction. The other of the pair of the holes contains a cam member.

Abstract: A hydraulic puncher includes a puncher body housing an actuator, a reciprocal ram shaft and a punch holder having one end rotatably connected to the end of the ram shaft. Punches are arranged in the other end of the punch holder. A C-shaped frame has an opening opened perpendicularly to the axis of the puncher body and one end integrally connected to the puncher body. A die holder has one end removably connected to the other end of the C-shaped frame and dies are connected to the other end of the die holder and each having holes for receiving the punches. A first connecting unit is provided for fixing the punch holder to the ram shaft so as to selectively cause the punch holder to extend toward the front side of and crosswise of the puncher. A second connecting unit is provided for fixing the die holder to the other end of the C-shaped frame so as to selectively cause the die holder to extend toward the front side of and crosswise of the puncher.

Abstract: A fluid connector is provided with a socket, a plug and a locking mechanism for locking the plug inserted in the socket. The socket has an axial passage and a first valve mechanism, for opening and closing the axial passage. The first valve mechanism includes a valve stem having one end fixed to the socket and the other end formed with a valve seat, a sleeve-like slide member movable in the axial passage with respect to the socket in a sealing state, a first packing provided on the slide member, for opening and closing the passage in cooperation with the valve seat, and urging means for urging the slide member toward the valve seat and causing it to abut against the first packing. The plug has an end portion capable of being inserted in the socket and a plug main body formed with an axial holes. A second valve mechanism for opening and closing the axial hole is provided in the plug main body.

Abstract: An apparatus for fixing an annular cutter to an arbor comprises an arbor and a rotation transmitting member coaxially fixed to the arbor. Inclined grooves which receives locking pins extend from the inner peripheral surface to the outer peripheral surface of the rotation transmitting member toward the arbor. A guide ring is axially slidably mounted on the rotation transmitting member and has pressing faces and restricting grooves defined by the pressing faces. Each restricting groove has a dimension which can receive the respective locking pin. A holding mechanism is provided for holding the guide ring in a normal state in which the pressing faces press the locking pins inward along the inclined grooves. The holding mechanism can moved toward the arbor together with the guide ring so as to allow the locking pins to enter the restricting grooves. An annular cutter has a cutter body and a shank connected to the cutter body and inserted into said rotation transmitting member.

Abstract: An annular cutter connecting apparatus includes an arbor, annular cutter fixing locking members received in holding holes formed in the lower end portion of the arbor and a sleeve member surrounding the lower end portion of the arbor, for fixing an annular cutter to the arbor. The sleeve has a first control face having an inner diameter equal to the outer diameter of the lower end portion of the arbor, for projecting the locking members into the central bore by a predetermined length when the first control face engages the locking members, and second control faces formed circumferentially in the first control face, for receiving the locking members. The sleeve is rotatable around its own axis so as to cause the locking members to selectively face the first control face and the second control faces, respectively.

Abstract: An annular cutter connecting apparatus includes an arbor, annular cutter fixing locking members received in holding holes formed in the lower end portion of the arbor and a sleeve member surrounding the lower end portion of the arbor, for fixing an annular cutter to the arbor. The sleeve has a first control face having an inner diameter equal to the outer diameter of the lower end portion of the arbor, for projecting the locking members into the central bore by a predetermined length when the first control face engages the locking members, and second control faces formed circumferentially in the first control face, for receiving the locking members. The sleeve is rotatable around its own axis so as to cause the locking members to selectively face the first control face and the second control faces, respectively.

Abstract: A socket of a pipe joint has a socket body, coupled to an end portion of a first fluid pipe, for removably receiving a plug coupled to an end portion of a second fluid pipe to be coupled to the first fluid pipe, a valve mechanism provided within the socket body and situated in an open position to allow passage of a fluid between the socket body and the plug when the plug is inserted in the socket body, and a lock mechanism for preventing removal of the plug from the socket body when the valve mechanism is situated in the open position.