Abstract: An output part is provided to the left end of a clamp arm that is supported by a housing so as to be slidable in the vertical direction. At the left end of the housing, a first hole for spring fitting opens obliquely upward towards the output part. A through hole that links the upper surface and the lower surface of the clamp arm is disposed obliquely upward at a left-leaning part of the clamp arm. A second hole for spring fitting and a female screw hole are formed, in that order, upwards in the through hole. A return spring that is installed through the first hole and the second hole impels the output part upwards. A push bolt that is screwed into the female screw hole rom above compresses the return spring.

Abstract: A first piston for high load is inserted into a housing so as to be movable vertically, and a second piston for low load is inserted into a cylindrical hole of the first piston so as to be movable vertically. An output portion projects from the second piston to above the housing. A first spring for high load and a second spring for low load are mounted in a spring chamber defined by both pistons and. Both springs and are mounted so as to urge the first piston and the second piston upward. A switching mechanism disposed in the pressure fluid chamber at a side opposite to the spring chamber, connects the first piston selectively to the housing or the second piston.

Abstract: A first piston (10) is inserted in a housing (2) so as to be hermetically movable vertically. A second piston (20) is inserted in a cylindrical hole (14) of the first piston (10) so as to be hermetically movable axially, and has an output rod (26) projecting upward from the housing (2). A lock chamber (40) is formed below the first piston (10) and the second piston (20), and a release chamber (42) is formed above the first piston (10) and the second piston (20). A force multiplier (52) is arranged in the housing (2) so as to cause (i) a first force, with which a pressurized fluid supplied into the lock chamber (40) pushes the first piston (10) upward, to be transformed in a force-multiplying manner into a second force and (ii) the second force to be transmitted to the second piston (20). Further, a change-over mechanism (54) is arranged in the housing (2) so as to selectively couple the first piston (10) to the housing (2) or the second piston (20).

Abstract: A plug portion (27) is projected from a first block (1) so as to be inserted into a insertion hole (5) opened in a second block (2). A support surface (9a) is formed on the first block (1) so as to be brought into contact with a supported surface (2a) formed on the second block (2). In the support surface (9a) is opened a fluid flow hole (59). A gap supporting member (K) acting force upon the second block (2) in such a direction as to separate the second block (2) from the first block (1) so as to form a gap (G1) between the supported surface (2a) and the support surface (9a) is provided on the first block (1). A pull member (21) eliminates the gap (G1) by making the second block (2) approach the first block (1) against the force of the gap supporting member (K) in such a condition that an outer peripheral surface of the plug portion (27) is in close contact with an inner peripheral surface of the insertion hole (5) to bring the supported surface (2a) into contact with the support surface (9a).

Abstract: A clamp rod (6) inserted into a guide hole (5) of a housing (4) has: a clamping member (10); an inner piston (12); and a tapered pressure receiving surface (13), which are provided in this order in an axial direction from a left end to a right end. An output portion (26) for locking and releasing is provided on an inner periphery of a right end portion of one outer piston (23) inserted between the inner piston (12) and the guide hole (5). A collet (33) inserted between the pressure receiving surface (13) and the guide hole (5) is formed of four divided members (34) arranged circumferentially at substantially regular intervals. An input portion (36) driven by the output portion (26) and a pressing surface (40) which makes a wedge-engagement with the pressure receiving surface (13) from a right side are respectively provided in an outer periphery portion and on an inner periphery portion of each divided member (34).

Abstract: A clamp rod (6) inserted into a guide hole (5) of a housing (4) has: a clamping member (10); an inner piston (12); and a tapered pressure receiving surface (13), which are provided in this order in an axial direction from a left end to a right end. An output portion (26) for locking and releasing is provided on an inner periphery of a right end portion of one outer piston (23) inserted between the inner piston (12) and the guide hole (5). A collet (33) inserted between the pressure receiving surface (13) and the guide hole (5) is formed of four divided members (34) arranged circumferentially at substantially regular intervals. An input portion (36) driven by the output portion (26) and a pressing surface (40) which makes a wedge-engagement with the pressure receiving surface (13) from a right side are respectively provided in an outer periphery portion and on an inner periphery portion of each divided member (34).

Abstract: A plug member (12) inserted into a positioning hole (5) formed in a second block (2) is projected from a first block. Two slide portions (61, 61) opposed to each other across the plug member (12) are arranged around the plug member (12) movably in a first radial direction (D1) substantially orthogonal to the opposed direction. An annular pressing member (15) which is allowed to diametrically expand and diametrically contract is arranged around an outer periphery of the slide portion (61, 61). The slide portions (61, 61) diametrically expand the pressing member (15) in a second radial direction (D2) which is the opposed direction by a drive device to press the pressing member (15) against an inner peripheral surface of the positioning hole (5), by which the slide portions (61, 61) are moved in the first radial direction (D1) with respect to the plug member (12).

Abstract: A plug member (12) inserted into a positioning hole (5) formed in a second block (2) is projected from a first block (1). A plurality of slide portions (61) opposed to each other across the plug member (12) are arranged around the plug member (12) movably in a first radial direction (D1) substantially orthogonal to the opposed direction thereof. A first pressing member (15) and a second pressing member (19) are arranged outside the slide portions (61) diametrically expandably and diametrically contractibly and axially movably. The first pressing member (15) is driven toward a base end by a drive device, whereby the slide portions (61) expand the first pressing member (15) via the second pressing member (19), thereby the slide portions (61) are moved in the first radial direction (D1) with respect to the plug member (12).

Abstract: A plug member (12) inserted into a positioning hole (5) formed in a second block (2) is projected from a first block (1). A plurality of slide portions (61) opposed to each other across the plug member (12) are arranged around the plug member (12) movably in a first radial direction (D1) substantially orthogonal to the opposed direction thereof. A first pressing member (15) and a second pressing member (19) are arranged outside the slide portions (61) diametrically expandably and diametrically contractibly and axially movably. The first pressing member (15) is driven toward a base end by a drive device, whereby the slide portions (61) expand the first pressing member (15) via the second pressing member (19), thereby the slide portions (61) are moved in the first radial direction (D1) with respect to the plug member (12).

Abstract: In a reference block (1), a center hole (20) having a tapered inner surface (23) narrowing downward is provided. A rigid sleeve (21) having a tapered outer surface (27) making a tapering engagement with the tapered inner surface (23) is supported by the reference block (1) axially movably. During a locking drive, an output member (48) inserted into the rigid sleeve (21) is moved downward. Then, a clamping member (33) inserted into a socket hole (3) of a work pallet (2) is moved downward against an elastic member (45) and radially-outwardly for locking, and the tapered outer surface (27) of the rigid sleeve (21) makes a tapering engagement with the tapered inner surface (23).

Abstract: A female screw hole (31) is opened in an outer surface of a housing (3) of a hydraulic clamp (1), and a leg portion (40a) of a tubular casing (40) is threaded into the female screw hole (31). An annular gasket (41) is fitted to an annular groove (42) formed in a head portion (40b) of the casing (40). On an inner peripheral surface (41a) of the gasket (41), a first annular sealing portion (71) which seals an inner peripheral surface (42a) of the annular groove (42) is provided. On an annular outer end surface (41d) of the gasket (41), a second annular sealing portion (72) which seals a peripheral wall (68) of the female screw hole (31) at the opening part of the housing (3) is provided. A diameter (D1) of the first annular sealing portion (71) is set to a value smaller than a diameter (D2) of the second annular sealing portion (72).

Abstract: An annular piston (21) is inserted into a cylinder hole (20) of a housing (4) so as to be vertically movable and be prevented from rotating. Into a cylindrical hole (24) of the piston (21), a cylindrical rotating member (25) is inserted while prevented from moving vertically. A ball screw mechanism (28) is provided between the piston (21) and the rotating member (25). On an outer peripheral surface of the rotating member (25), a circulation passage (59) which communicatively connects a start end and a terminal end of a male spiral groove (56) is formed in a recessed manner. Into a guide hole (29) formed in an upper half of the housing (4), an output rod (30) is inserted rotatably and movably vertically. An input portion (41) of the output rod (30) is connected to the rotating member (25) so as to transmit rotation. By driving the piston (21) upward, a bolt (45) provided on an upper end portion of the output rod (30) is engaged with an internal threaded hole (12) of a work (10).

Abstract: A piston (19) inserted into a cylindrical housing (2) is connected to a clamp rod (5). A lock chamber (20) is provided above the piston (19), and an annular valve chamber (41) is formed in a peripheral wall of a rod hole (18) into which the clamp rod (5) is inserted. At a last stage of swing ascending of the clamp rod (5), a shuttle member (42) fitted at the outside of a lower portion of the clamp rod (5) ascends and fits into the valve chamber (41) due to a differential pressure of a pressurized oil applied when the shuttle member (42) starts to fit into the valve chamber (41). Then, a flow rate of the pressurized oil to be discharged from the lock chamber (20) is controlled by a restriction gap between the shuttle member (42) and the clamp rod (5). At an early stage of swing descending of the clamp rod (5), a flow rate of the pressurized oil to be supplied to the lock chamber (20) is controlled by a restriction gap between the valve chamber (41) and the shuttle member (42).

Abstract: Inside a cartridge-type cylindrical casing (40), a meter-out inlet (43), a valve chamber (44), a rod chamber (46), and a meter-out outlet (47) are formed in that order. The rod chamber (46) and the valve chamber (44) are arranged substantially concentrically, and a check valve seat (53) is provided on an inner peripheral surface of a peripheral wall (44a) of the valve chamber (44). A check ball (52) inserted in the valve chamber (44) is urged toward the check valve seat (53) by a spring (54). A throttle valve seat (59) is provided on a leading end portion of an adjusting rod (45) screwed in the rod chamber (46), and a throttle gap (G) is formed between the throttle valve seat (59) and the check ball (52).

Abstract: An annular piston (21) is inserted into a cylinder hole (20) of a housing (4) so as to be vertically movable and be prevented from rotating. Into a cylindrical hole (24) of the piston (21), a cylindrical rotating member (25) is inserted while prevented from moving vertically. A ball screw mechanism (28) is provided between the piston (21) and the rotating member (25). On an outer peripheral surface of the rotating member (25), a circulation passage (59) which communicatively connects a start end and a terminal end of a male spiral groove (56) is formed in a recessed manner. Into a guide hole (29) formed in an upper half of the housing (4), an output rod (30) is inserted rotatably and movably vertically. An input portion (41) of the output rod (30) is connected to the rotating member (25) so as to transmit rotation. By driving the piston (21) upward, a bolt (45) provided on an upper end portion of the output rod (30) is engaged with an internal threaded hole (12) of a work (10).

Abstract: A plug member (12) inserted into a positioning hole (5) formed in a second block (2) is projected from a first block (1). A plurality of slide portions (61) opposed to each other across the plug member (12) are arranged around the plug member (12) movably in a first radial direction (D1) substantially orthogonal to the opposed direction thereof. A first pressing member (15) and a second pressing member (19) are arranged outside the slide portions (61) diametrically expandably and diametrically contractibly and axially movably. The first pressing member (15) is driven toward a base end by a drive device, whereby the slide portions (61) expand the first pressing member (15) via the second pressing member (19), thereby the slide portions (61) are moved in the first radial direction (D1) with respect to the plug member (12).

Abstract: A housing (15) fixed to a reference block (1) is provided with a guide hole (20) into which a plug portion (3) of a movable member (2) is allowed to be inserted. Inside this guide hole (20) is arranged an outer sleeve (21) vertically movably, and this outer sleeve (21) is advanced upward by a predetermined advancing stroke by a coned disc spring (25). An inner sleeve (31) which is allowed to fit outside the plug portion (3) is wedge-engaged with the outer sleeve (21) from above, and this inner sleeve (31) is adapted to be diametrically expandable and diametrically contractible. The inner sleeve (31) is moved vertically by an output member (36).

Abstract: A central pillar (20) is projected upward from a reference block (1), and an inner sleeve (21) is fitted to an outer periphery of the central pillar (20) vertically movably. The inner sleeve (21) is pushed upward by a coned disc spring (25). An outer sleeve (31) to be inserted into a socket hole (3) of a movable block (2) makes a tapering engagement with the inner sleeve (21) from above. The inner sleeve (21) and the outer sleeve (31) are adapted to be diametrically expandable and contractible. An output member (36) is inserted into the central pillar (20), and an upper portion of the output member (36) is connected to the outer sleeve (31). A driving mechanism (D) in the reference block (1) moves the outer sleeve (31) downward for locking via the output member (36).

Abstract: A housing (6) is provided in a reference block (1). An annular plug (9), which is to be inserted into a positioning hole (3) of a work pallet (2), is projected upward from the housing (6). An output member (13) is inserted into a guide hole (10) of the housing (6) vertically movably. An upper end of the output member (13) is inserted into the annular plug (9), and a plurality of pressing members (56) are supported on a peripheral wall (9a) of the annular plug (9) radially movably. An annular aligning space (31) is formed between a guided portion (21) of the output member (13) and the guide hole (10). A shuttle member (41), which is diametrically expandable and contractible, is inserted into the aligning space (31). The shuttle member (41) is urged upward by a spring (51).

Abstract: A plug member (12) inserted into a positioning hole (5) formed in a second block (2) is projected from a first block (1). A plurality of slide portions (61) opposed to each other across the plug member (12) are arranged around the plug member (12) movably in a first radial direction (D1) substantially orthogonal to the opposed direction thereof. A first pressing member (15) and a second pressing member (19) are arranged outside the slide portions (61) diametrically expandably and diametrically contractibly and axially movably. The first pressing member (15) is driven toward a base end by a drive device, whereby the slide portions (61) expand the first pressing member (15) via the second pressing member (19), thereby the slide portions (61) are moved in the first radial direction (D1) with respect to the plug member (12).