Abstract: In a check valve with a valve opening device, a check valve member (32) inserted into a check valve chamber (21) formed in a valve box (20) is resiliently urged for valve closing by means of a check spring (33) as well as the check valve member (32) is manipulated for valve opening through a manipulation lever (45), an actuator shaft (43) and a valve opening member (36) in order. The valve opening member (36) is adapted to be held at a valve opening position (F) by means of a valve opened state holding means (38). The valve opened state holding means (38) is arranged in both the valve opening member (36) and the valve box (20). A manipulation lever return spring (46) is disposed in a manipulation force transmitting system from the manipulation lever (45) to the valve box (20) through the actuator shaft (43).

Abstract: In a hydraulic clamp with a direct operated rotary clamping-member, a clamping-member (6) is fixedly secured to the lower portion of a clamp rod (22) adapted to be actuated by a hydraulic cylinder (12). When the hydraulic cylinder (12) is actuated for clamping, the clamping-member (6) is upward straightly actuated and changed over to a clamping condition (C) after being rotated to a clamping preparation condition (B) from an unclamping condition (A), through a rotary actuation device (13) and the clamp rod (22). The clamp rod (22) is interlockingly connected to a rotary member (27) of the rotary actuation device (13) in the rotatably actuated and slidably lowered state with respect to the rotary member (27).

Abstract: An actuation member (B) supported by a housing (A) is actuated for clamping upwardly by means of a spring force and actuated downwardly for unclamping by means of an actuation means (D). A piston (11) is inserted into a cylinder (10) fixedly secured to the upper portion of the housing (A), and a liquid sealing chamber (12) is formed below the piston (11). The piston (11) is fixedly secured to the actuation member (B). When the actuation member (B) is held in the clamped condition, a liquid sealing valve (15) is closed so as to seal an oil (L) within the liquid sealing chamber (12). Whereby, in case that a pulling down force larger than the clamping spring force is imposed to the actuation member (B), a pressure generated within the liquid sealing chamber (12) serves to prevent the piston (11) from lowering, against the pulling down force.

Abstract: In a three way valve assembly with a pressure compensating valve, a three way valve (2) is adapted to selectively communicate a work port (A) to a pressure supply port (S) and to a pressure discharge port (T). A pressure compensating valve (3) is adapted to release a pressure abnormally raised at a very slow speed within the work port (A) to the pressure discharge port (T). A first housing (10) of the three way valve (2) is fixedly secured between left and right end plates (4) (5) by means of assembly bolts (6) (7). A second housing (57) of the pressure compensating valve (3) is fixedly secured to one end surface (10c) of upper, lower, front and back end surfaces of the first housing (10) by means of a fixing means (67).

Abstract: A hydraulic clamp includes an inclined direct operated clamping member, a cylinder bore formed in a housing in such an inclined manner as forwardly descending, a piston inserted into the cylinder bore, a clamping actuation hydraulic chamber formed behind the piston within the cylinder bore, and a clamping member forwardly protruding from the upper portion of the front end of the piston. A spring accommodation recess is formed so as to extend rearward from the piston front end, and a spring retainer is supported by the housing in front of the piston. An unclamping spring is installed between the spring retainer and a spring retaining seat formed in the rearward most portion of the spring accommodation recess.

Abstract: An upper portion (3a) of an upper-die (3) is fixedly secured to a lower portion (2) of a ram (1) extending horizontally by way of a first clamping member (5) and a second clamping member (6) therebetween from both the fore side and the back side. The second clamping means (6) comprises a plurality of press plates (8)(8) arranged side by side in the horizontal direction. An opperating oil chamber (20) of a hydraulic cylinder (19) provided in each press plate (8) is connected in communication to a pressurized oil outlet port (42) and to a pressurized oil inlet port (41) both of which are opened in laterally opposed end surfaces (8b)(8a) of the press plate (8) respectively. The pressurized oil outlet port (42) and the pressurized oil inlet port (41) facing each other of the adjacent press plates (8)( 8) are connected in communication to each other by means of an interconnection pipe ( 23).

Abstract: In an apparatus and a method for replacing a working-object of a processing machine, there are provided a working-object replacing support (6), a working-object moving passage (12) and a push/pull drive means (18) for the working-objects (5a)(5b).The push/pull drive means (18) is provided with a push/pull drive device (19), a push/pull engaging member pedestal (20), a push/pull transmission member (21), a guide rail (22) and a push/pull engaging member (23).An engaging portion (59) of the engaging member (23) is adapted to be shifted to a position lower than height positions of lower surfaces of engaged portions (25)(26) of the working-objects (5a)(5b) under the changed over condition to the disengagement position (Y) and at least to face upward so as to be engaged with the engaged portions (25)(26) from below under the changed over condition to the engagement position (X).

Abstract: An attachment of a gas charger for a gas container is adapted to be mounted to a valve device with a check valve and to be used for forcedly opening a spring-closed type check valve by means of a charging pressure of a fresh gas. The attachment is provided with a gas charging mouthpiece detachably secured to a valve box of the valve device, a piston supporting member movable together with the gas charging mouthpiece, and a valve-opening piston. The valve-opening piston is sealingly supported by the piston supporting member in such a condition as being freely movable in the diametrical direction and is detachably sealingly fitted into a received pressure removing cylinder room of a check valve member.

Abstract: An apparatus for driving a piston by fluid pressure in which a piston (8) is reciprocated upward and downward by supplying and discharging pressure fluid to and from an actuation chamber (9) disposed in a cylinder (7) through a pilot valve (18) and a fluid pressure supply-discharge valve (13). Above a supply-discharge valve member (30) of the supply-discharge valve (13) there is provided a cylinder chamber (70a), into which a pilot valve casing (71) is inserted so as to hermetically slide up and down. The fluid pressure in the discharge actuation chamber (35) disposed above the supply-discharge valve member (30) allows the pilot valve casing (71) to ascend against a return spring (73).

Abstract: A control valve assembly for a pressurized oil has a valve chamber (4) within which a pressure supply valve seat (15), a first chamber (11), a short-circuit prevention valve seat (17), a second chamber (12) and a return valve seat (16) are arranged in order. A check valve member (19) inserted into the first chamber (11) is adapted to be resiliently urged to the pressure supply valve seat (15) for valve closing by means of a valve closing spring (19) through a resilient sealing member (21). A return valve member (22) and a short-circuit prevention valve member (23) are inserted into the second chamber (12) in series. The return valve member (22) is adapted to be resiliently urged to the return valve seat (16) for valve closing by means of another valve closing spring (30).

Abstract: The present invention relates to a workpiece pallet changer which changes a work pallet fitted on a pallet positioning device on the table of a machine tool. The changer comprises a moveable pallet mounting assembly disposed at plural locations along the peripheral surface of a rotatable frame, each of which engages a work pallet to permit transfer of the work pallet between the pallet mounting assembly located on the surface of the rotatable frame and the pallet positioning device, while simultaneously allowing chips fall automatically from the work pallet as it rotates downward.

Abstract: A first coupling (51) and a second coupling (52) composing a quick-acting coupling (26) are respectively provided with check valve bodies (54)(154) and non-spill valve bodies (55)(155). When both the couplings (51)(52) are manipulated for the disconnection thereof, a leak of liquid is adapted to be prevented by means of the respective check valve bodies (54)(154) as well as a spill of liquid is adapted to be prevented by means of the non-spill valve bodies (55)(155). The respective non-spill valve bodies (55)(155) are fitted slidably inside respective non-spill valve port surfaces (71)(171) so as to carry out a liquid sealing respectively. Further, at the time of disconnecting manipulation of the coupling (26), a volume of the liquid phase portion within a non-spill valve casing chamber (63) is adapted to be increased by the movement of a non-spill valve casing (56) in which the first non-spill valve body (55) is fitted.

Abstract: A first coupling (51) and a second coupling (52) composing a quick-acting coupling (26) are respectively provided with check valve bodies (54)(154) and non-spill valve bodies (55)(155). When both the couplings (51)(52) are manipulated for the disconnection thereof, a leak of liquid is adapted to be prevented by means of the respective check valve bodies (54)(154) as well as a spill of liquid is adapted to be prevented by means of the non-spill valve bodies (55)(155). The respective non-spill valve bodies (55)(155) are fitted slidably inside respective non-spill valve port surfaces (71)(171) so as to carry out a liquid sealing respectively. Further, at the time of disconnecting manipulation of the coupling (26), a volume of the liquid phase portion within a non-spill valve casing chamber (63) is adapted to be increased by the movement of a non-spill valve casing (56) in which the first non-spill valve body (55) is fitted.

Abstract: A hydraulic clamp, which actuates a clamping means by a hydraulic pressure of a hydraulic cylinder, has a clamping actuation oil chamber, a piston and the clamping means arranged in a cylinder body of the hydraulic cylinder in this order in the axial direction of the hydraulic cylinder. The clamping means is adapted to be shifted expansively and contractively between advanced position clamping and a retracted position (unclamping) which are at different distances from the axis of the hydraulic cylinder. The clamping means is adapted to be advanced from the retracted position to the advanced position in an early stage of the application of a hydraulic actuation force in the clamping actuation oil chamber, by which the piston is hydraulically actuated, and the clamping means is adapted to be actuated for clamping by a latter stage of the hydraulic pressure in the clamping actuation oil chamber.

Abstract: There are provided coned disc springs and an intermediate transmission member in order between a thrust threaded member for generating the valve closing thrust and a valve body, and the intermediate transmission member is adapted to be urged by means of the coned disc springs toward the valve closing side with respect to the thrust threaded member. A contact receiving means is so arranged as to limit the movement of the thrust threaded member toward the valve closing side, and a contact receiving position of the contact receiving means is set at a midway position of the compression range of the coned disc springs. Wherein, the handle is adapted to be changed over between the handle held condition and the handle released condition by the relative movement of the intermediate transmission member with respect to the thrust threaded member.

Abstract: A cylinder type hydraulic clamp having a clamping mechanism is adapted to be actuated by means of a hydraulic cylinder, and has a piston rod projected through the cylinder body of the hydraulic cylinder and is equipped at its leading end portion with the clamping means. The clamping means is arranged concentrically with the piston rod and is adapted to be resiliently urged by means of a contraction spring toward its contracted position to be pushed by means of an expansion slant cam toward its expanded position. At the time of the clamping actuation, when the clamping means is hydraulically actuated toward the cylinder body through the piston and the piston rod, the clamping means is first expanded diametrically by means of the expansion slant cam against the resilient force of the contraction spring and then a member to be clamped is fixedly pressed between the cylinder body and the clamping means expanded as mentioned above.

Abstract: A pneumatic-hydraulic booster type driving device for the cushion-knockout mechanism associated with the slide of a press-machine serves to stably hold down a work plate such as a printed board and the like while performing a cushion operation at the time of a pressing stroke and serves to knock out the work plate after the pressing stroke in the press-machine. In the driving device, a pneumatic-hydraulic booster is connected through a pressure oil supply and discharge means to a hydraulic actuation chamber of a cushion cylinder provided in the slide of the press-machine, and the pressure oil supply and discharge means comprises a valve chamber within a valve casing and a knockout actuator which is fixedly secured to the valve casing so as to perform the valve opening operation of the valve unit.

Abstract: In a plunger pump system of a quick pressure-rise type which is utilized for increasing the pressure of a working fluid to be supplied quickly to a hydraulic actuator, such as an oil hydraulic cylinder, both a high pressure plunger pump and a quick-charging pump are connected interlockingly to one prime mover so as to be driven synchronously. During a low pressure range of operation, a large amount of working fluid delivered from a quick-charging plunger chamber is adapted to be supplied to the hydraulic actuator through a high pressure plunger chamber. On the other hand, during a high pressure range of operation, a small amount of high pressure working fluid is adapted to be delivered from the high pressure plunger chamber to the hydraulic actuator.

Abstract: A hydraulic overload protector for a mechanical press is provided with a cylindrical operational oil chamber which is formed in a vertical direction. A piston is vertically slidably inserted into a slide. The operational oil chamber is provided with a friction-contacting cylinder. During press operation, the hydraulic pressure of the operational oil chamber fixes the slide to the piston at a predetermined force through the friction-contacting cylinder, so that a pressing force is transmitted from the piston to the slide from an overload. When the slide is overloaded by foreign matter, the piston slides downwards in the slide in resistance to the piston-fixing force, whereby an overload-safe operation is effected.

Abstract: In a die-height adjusting device of a mechanical press, a slide of the mechanical press is interlockingly connected to a prime mover through a slide actuating mechanism, and an extendible and contractible device for the adjustment of the die-height is provided at the part between the output end portion of the slide and the slide actuating mechanism supported by a frame. The extendible and contractible device is adapted to be adjusted and stopped in the extending and contracting direction thereof by an operating device for the extension and contraction adjustment. Said extendible and contractible device for the adjustment of the die-height comprises an extending and contracting mechanism and a clamp. Said operating device for the extension and contraction adjustment comprises an actuating means for the extending and contracting mechanism and a clamp actuating means.