Abstract: An annular hole cutter has a radially inner cutting tooth portion and a radially outer cutting tooth portion. Each of the inner and outer cutting tooth portions is formed with a flute for ejecting cut chips on the outer periphery of the cutter, and a cutting edge for radially outwardly pushing the cut chips. Therefore, the cut chips are smoothly ejected through the flute, and thus an annular hole is precisely cut at high speed.

Abstract: A chamfering device comprising a housing in which a motor is housed, a guide base arranged at one end of this housing, a rotating shaft which is driven by the motor and whose front end is projected outside from the guide base, a chamfering blade fixed to the front end portion of the rotating shaft, partly projecting outside from the guide base, and a guide located further on the front side of the rotating shaft than the chamfering blade and attached to the front end of the rotating shaft. The guide can be contacted with the face adjacent to the chamfering portion of a workpiece.

Abstract: A forging method comprises the following four steps: a first step of disposing a columnar material into a first die and extruding one end portion of the material with a first punch in a direction opposite to the advancing direction of the first punch, a second step of deepending a first blind hole in a second stepped die with a cavity having large and small internal diameter portions, and extruding the other end portion of the material into the inside of the small internal diameter portion of the cavity with a second punch which has been previously extended thereinto, a third step of fitting the first and second blind holes to third punches while exposing the small outer diameter portion from a third die and pressurizing, by means of a sleeve, only an end face portion of the small outer diameter portion formed with the second blind hole to expand the small outer diameter portion of the material toward an outer periphery, and a fourth step of punching out a blind portion of the material.

Abstract: A pallet changer has a pallet support rotatably provided on a bed and a plurality of pallet inlet/outlets disposed on the edges of the pallet support at regular intervals. Positioning pins are biased such that they project from the bed toward the pallet support. Stops are provided on the pallet support and are engaged with the positioning pins, when the pallet support is turned through an angle corresponding to the angular distance between adjacent pallet inlet/outlets. A control mechanism is provided such that when a pallet is transferred to the pallet support through one of the pallet inlet/outlets, the positioning pin is held disengaged from the corresponding stop until the pallet support is rotated to the next stop position.

Abstract: A connecting member comprises a rod-shaped body having a head and/or thread on the outer periphery for integrally connecting a plurality of members and a containing hole opened at one end thereof and extended longitudinally, a rod disposed in the hole so as to fix at its inner end to the inner end of the hole, a transmissive window fixed to the opening of the hole, and a fluid holding member holding a colored fluid and pressed by the open side end of the rod on the window. When a longitudinal strain developed in the body the rod release the holding member from under pressure so that colored fluid covers the open side end of the rod.

Abstract: In a clamping apparatus, a pressing member is moved on a base in a vertical and horizontal directions by rotation of a bolt. The bolt is provided with a longitudinal hole open end of which is covered by a window. A rod is placed in the hole so as to fix the inner end thereof to the inner end of the hole. A transparent holding member holding a colored fluid is sandwiched by the open side end of the rod and the window. When a tension stress is developed in the bolt, the open side end is far away from the holding member so that fluid covers the open side end.

Abstract: A clamping device has a clamp base having a first clamping element. A second clamping element faces the first clamping element, which moves toward the first clamping element and cooperates with the first clamping element to hold an article. A shaft is rotatably provided in the crank base such that it extends substantially at right angles to the directions in which the second clamping member moves. An eccentric is formed on the shaft. A crank lever is supported at one end by a crank holder connected to the second clamp element and fitted at the other end on the eccentric. As the shaft rotates, the second clamping element is moved towards or away from the first clamping element so as to hold the article between the elements or release the article from them.

Abstract: Pipe coupling usable for piping in pneumatic conditioning systems which has male and female assemblies each given in the form of a single united or single body and each provided with a valve assembly which can be incorporated into the associated assembly from the front side opening and set in prescribed position and posture without need for the conventionally employed swaging operations, and a valve closure body incorporated in the male assembly whose both fringes encroach upon corresponding surfaces formed on the male and female assemblies, respectively, in order to assure simplified preparation of the male and female assemblies, enhanced reliable fluid sealing effect even after a long use and release of assembly plants from the problem of chemical pollution of the environment.