The invention pertains to a reference positioning system for positioning a workpiece in a three-dimensional coordinate system, the reference positioning system comprising a first positioning unit for positioning a first alignment feature of the workpiece in a first dimension, in a second dimension and in a third dimension, comprising a first centring pin and a first reference level locator, a second positioning unit for positioning a second alignment feature of the workpiece in the second dimension and in the third dimension, comprising a second centring pin and a second reference level locator, and a third positioning unit for positioning a third alignment feature of the workpiece in the third dimension, comprising a third reference level locator.

A clamp apparatus includes a support body that projects in a sideways direction of a body, together with a clamp arm, which is disposed rotatably in facing relation to the support body. On the support body, a support member, which extends in a horizontal direction, is disposed detachably with respect to a coupling hole of the body, whereas a connecting body, which interconnects a pair of arm members, is disposed detachably on an end of the clamp arm. A clamp release mechanism, which releases a clamped state when the clamp arm is locked, is disposed in the body, and is configured to press a joint of a driving force transmission mechanism that is accommodated in the body toward the side of a drive unit.

The present invention provides an improved release mechanism for clamping tools where problems of thread slipping due to worn out thread can be reduced by the structure of a plunger with a small diameter section and the engagement of the thread shaft is made more secure by the cam action on account of the shape of the plunger. A protrusion extends from a push button on a top portion of the half-threaded nut. Threads are formed on an upper portion of the hole for engaging the threaded shaft. The middle portion of the plunger is made to have a section of small diameter allowing the protrusion to be pushed downward in a normal position and allowing the protrusion to rely on the resilient power of the helical spring to push it upward into the small diameter section.

A piston body (11) of an advancing-retracting first piston (10) and a force-multiplying second piston (15) are arranged in series in a vertical direction in a housing (1). Force acting on the second piston (15) due to pressurized oil in a lock chamber (16) is multiplied and converted into multiplied upward force via engaging balls (32) of a force multiplier (30). Then, the multiplied upward force is transmitted to an output rod (12) of the first piston (10). At an intermediate part of a first air detection passage (38) for use in detection formed in the housing (1), a first detection valve (40) is provided. When the engaging balls (32) move inward in a radial direction, the first detection valve (40) is closed.

A centering clamping apparatus has a housing (1) with a centering element (2) mounted to be displaceable along a longitudinal axis between an open position and a clamping position. A finger element (3), mounted with centering element (2), is displaceable transversely to the longitudinal axis between a retracted position and an extended position. The finger element (3) is operatively connected to an adjusting member (4). The adjusting element (4) is mounted to be displaceable in the centering element (2). A blocking device (5) is provided on the centering element (2). The blocking device (5) either precludes a relative movement between the housing (1) and the centering element (2), with the finger element (3) fully retracted, or precludes a relative movement between the centering element (2) and the adjusting member (4), with the finger element (3) fully extended.

The present invention relates to a clamp device. The clamp device is provided with a driving force transmission mechanism, which transmits driving force from a drive unit to clamp arms. The driving force transmission mechanism converts the rectilinear movement of a piston rod of the drive unit into: a first operation, in which the clamp arms rotate while moving in directions toward or away from each other; and a second operation, in which the clamp arms move in parallel in directions toward or away from each other with gripping surfaces in a mutually parallel state.

A clamp apparatus includes a pair of first and second clamp arms supported rotatably on a body. The clamp apparatus also includes a manual release mechanism capable of manually releasing a clamped state in the case that an output from a drive unit to the first and second clamp arms is stopped and the clamped state of a workpiece is locked. The manual release mechanism includes a release lever disposed rotatably on a first plate body. By an operator operating the release lever to thereby rotate the release lever, a block body of a driving force transmission mechanism is pressed and moved upwardly, and pressing forces applied to the first and second clamp arms in widthwise outside directions thereof by a pair of rollers, are released. Consequently, gripping members of the first and second clamp arms are rotated in directions away from each other to thereby cause an unclamped state.

The apparatus (1) for clamping workpieces on machine tools comprises: a basic frame (2) fixable to a machine tool (M) for machining a workpiece (P); a clamping unit (3); a hydraulic actuator (22, 23) comprising a first chamber (26) which can be supplied with a first pressurized hydraulic fluid and is connectable to a first sensing device (27) for sensing the pressure of the first hydraulic fluid; a sensing channel (15) which can be supplied with pressurized air and which is connectable to a sensing sensor (16) for sensing the pressure of the air;
wherein the first sensing device (27) and the sensing sensor (16) are connectable to a control system adapted to authorize the machining of the workpiece (P) when the pressure of the first hydraulic fluid and the pressure of the air are simultaneously higher than their respective threshold values.

A method of stopping vibration of a columnar work during processing thereof, includes the steps of providing a cylindrical columnar work having an outer circumferential surface divided into a non-processed region and at least two recessed processed regions with a circumferential cross-section forming a perimeter including two spaced apart non-processed perimetric segments separated by two spaced apart processed perimetric segments, providing a vibration stop including only two holding parts having arc shaped surfaces, locating the columnar work between the arc shaped surfaces of the holding parts adjacent the perimeter with each processed region radially inward, orienting the columnar work such that each arc shaped surface contacts the outer circumferential surface at both spaced apart non-processed perimetric segments with one processed perimetric segment located therebetween, each arc shaped surface, and holding the columnar work with the holding parts to prevent vibration of the columnar work during processing of the columnar work.

In a rod hole (19) of a holding rod (18) held in a guide hole (17) of a piston (10), a limit switch (20) is fixed and a detection rod (21) is inserted. A first engagement ball (30) and a second engagement ball (40) are configured to be in contact with a first cam surface (32) and a second cam surface (42), respectively, which are provided at an outer periphery of the detection rod (21). The first engagement ball (30) and the second engagement ball (40) are configured to be in contact with a first pushing portion (35) and a second pushing portion (45), respectively, which are provided inside the guide hole (17). The position of the piston (10) is detected by electrically or electronically detecting the movement of the detection rod (21) by the limit switch (20).