A clamping device for clamping a workpiece or a tool or, more specifically, a tool holding fixture in a machine part of a machine tool includes a tension rod slidably mounted within the machine part; a clamping set movable by the tension rod between clamped and released positions; a tension spring dedicated to the tension rod so as to generate the pull-in force of the clamping set; and a release mechanism, by which the clamping set can be moved against the force of the tension spring into the released position by the tension rod. To make possible effective clamping at optimum force, the tension spring is clamped between first and second rod parts of the tension rod. The second rod part can move relative to the first rod part, and, as the clamping set moves into the released position, is compressed on both ends by the release mechanism by moving the two rod parts in opposite directions.

A clamping device for clamping a workpiece or a tool or, more specifically, a tool holding fixture in a machine part of a machine tool includes a tension rod slidably mounted within the machine part; a clamping set movable by the tension rod between clamped and released positions; a tension spring dedicated to the tension rod so as to generate the pull-in force of the clamping set; and a release mechanism, by which the clamping set can be moved against the force of the tension spring into the released position by the tension rod. To make possible effective clamping at optimum force, the tension spring is clamped between first and second rod parts of the tension rod. The second rod part can move relative to the first rod part, and, as the clamping set moves into the released position, is compressed on both ends by the release mechanism by moving the two rod parts in opposite directions.

A vacuum suction pad capable of making it more difficult to separate a substrate when the substrate is held by vacuum suction, the vacuum suction pad 8 including: a pad main body 37 having a lower surface adhered to a stage 5 of a substrate holder 2; and a plurality of circular arc-shaped substrate holding convexities 38, provided on a top surface of the pad main body 37, for holding a substrate W attracted by vacuum suction to the top surface of the pad main body 37, wherein the substrate holding convexities 38 are arranged concentrically with the circular pad main body 37, and width W1 in a radial direction of the substrate holding convexity 38 located on a radially outer side among the plurality of substrate holding convexities 38 is narrower than width W2 in the radial direction of the substrate holding convexity 38 on a radially inner side.

A chuck mechanism operates a piston in a cylinder tube by using action of compressed air and opens and closes, by using a rod coupled to the piston, a pair of fingers, thereby gripping work W. The locking mechanism locks the fingers at work grip positions. The locking mechanism includes a first locking member, a second locking member, and a drive device. The first locking member is displaced when the pair of fingers are opened or closed. The second locking member retains the first locking member so as to lock the fingers at the work grip positions. The drive device relatively displaces the first locking member and the second locking member to locking positions and non-locking positions.

A hydraulic chuck device includes a cylinder portion operated by pressure oil, a chuck opened and closed by operation of the cylinder portion, a pressure oil supply controlling pressure of pressure oil supplied to the cylinder portion, and a chuck controller controlling the pressure oil supply. When controlling the pressure oil supply to cause a jaw portion to perform a clamping operation, during movement of the jaw portion from an unclamping position to a preliminary position situated before a clamping position, the chuck controller supplies pressure oil set at a first pressure into a cylinder chamber for clamping to move the jaw portion quickly, and during movement of the jaw portion from the preliminary position to the clamping positon, the chuck controller supplies pressure oil set at a second pressure lower than the first pressure into the cylinder chamber for clamping to move the jaw portion slowly.

Expansion sleeves are disclosed comprising a body and a flange. The body may be generally cylindrical and includes an inner wall, an outer wall integrally formed with the inner wall, and a pressurized fluid chamber located radially between and encapsulated in the inner wall and the outer wall. The front flange extends radially outward from the outer wall of the body. The front flange may comprise a tool support connection structured and arranged to fasten the front flange to a tool support member. The tool support member may include a pressurized fluid system that communicates with the pressurized fluid chamber of the expansion sleeve. The expansion sleeves may be secured to the tool support member by mechanical fasteners, threading, or combinations thereof. During operation, pressurized fluid in the tool support member communicates with the pressurized fluid chamber of the expansion sleeve to clamp a tool shank.

The invention relates to an expansion clamping sleeve (6) comprising a sleeve body (30) having a tool receptacle (24) for a chipping tool, wherein the sleeve body (30) is expanded in a longitudinal direction (10) as well as in a radial direction (20) transverse to the longitudinal direction (10), wherein the sleeve body (30) comprises a pressure membrane (44) delimiting a hydraulic chamber (40) in the sleeve body (30), and wherein the sleeve body (30) comprises a receptacle (46) for a mechanical actuator (48) for activating the pressure membrane (44). In addition, the invention relates to a hydraulic expansion clamping chuck (2) having such an expansion clamping sleeve (6).

A device (1) for clamping a workpiece (2) to be machined, in particular a chuck or vice, the device comprising: (i) a chuck body (3) and a drive (5) fastened thereto, and (ii) at least one clamping jaw (6), which is coupled to the drive (5) in a driveable arrangement either directly or via intermediate elements (7) and which is or are held movably in or on the chuck body (3) in the direction of the workpiece (2). On the one hand, reliable and centric clamping of the workpiece (2) in a predetermined position is achieved and, on the other hand, the mounting of the clamping jaw carrier (9) on the chuck body (3) is free of backlash in the clamped condition in order to prevent any possibility of movement of the workpiece (2) relative to the chuck body (3). This is achieved by providing a free space (11) between the chuck body (3) and a clamping jaw carrier (9) accommodating the respective clamping jaw (6), in that an elastically deformable sleeve (12) is inserted in the free space (11), which sleeve (12) rests on the outside (8) of the chuck body (3) at two positions (21) spaced apart from one another, and in that a pressure chamber (14) is created between the chuck body (3), the sleeve (12) and the two support positions (21) thereof, into which pressure chamber (14) a medium (16) can be filled, by means of which a pressure force directed outwards acts on the wall (W2) of the sleeve (12) and bulges the latter in the direction of the clamping jaw carrier (9) between the support positions (21).

The present application provides a material transferring and positioning device for a wheel machining center, which includes a base plate, a base, a first bearing, a first shaft sleeve, a hydraulic cylinder brake, a rotary cylinder, a cap and so on. The application may meet the positioning requirement of the wheel machining center, and has the advantages of simple structure, convenient manufacture, stable performance, high positioning precision and simple operation, so that it is very suitable for automatic mass production.

In one aspect, expansion sleeves for pressure-activated tool holder apparatus are described herein. An expansion sleeve, for example, comprises a first end, a second end and a longitudinal axis extending between the first end and the second end. A first set of fluid chambers are proximate the first end of the sleeve and a second set of fluid chambers are proximate the second end, wherein fluid channels extend along the longitudinal axis to connect radially offset fluid chambers of the first and second sets.