Abstract: A tool turret, in particular provided for the use for a machine tool, has a pivotable tool disk (10), which has on its outer circumference a plurality of receptacles (14) for holders (18) provided with working tools. The holders (18) are attached to the tool disk (10) in a changeable manner by a fixing device (20). Each holder (18) can be swiveled into a working position to permit the assigned working tool to be driven by a drive (22). For this purpose, the working tool can be coupled to an output shaft (16) of the respective holder (18) by a coupling device (26). The fixing device (20) can be actuated by the drive (22) when this drive (22) is uncoupled while stopping the working tool.

Abstract: In a machine tool having a tool carrier (1) that comprises at least one receptacle (4) for a tool holder (3) for driven or stationary tools a tool change device is provided that comprises gripping means (370) for gripping the tool holder (3) at the housing (7) or at part (71) connected with the housing (7). In addition to the gripping means the tool change device comprises a device for actuating the fastening means that are configured for attachment of the tool holder at the tool carrier.

Abstract: A robotic tool changer includes a locking mechanism that enhances safety. More particularly, the locking mechanism is an “over center” locking mechanism that maintains a constant lock force on a tool. The lock force exerted on the tool by the locking mechanism remains substantially constant, even after a motor providing power to the robotic tool changer is removed, and after the robotic tool changer experiences mechanical wear.

Abstract: A toolholder assembly includes a toolholder having a toolholder shank with a non-circular cross-section, a base member having a bore with a non-circular cross-section that receives the toolholder shank, a canister positioned in the base member, a lock rod positioned in the canister, a locking ball for cooperating with the lock rod, the canister and/or the toolholder shank and an actuating element configured for cooperation with the lock rod for moving the lock rod between a locked position and an unlocked position.

Abstract: A high-frequency spindle has a tube shaft extending along and rotatable about an axis, a chuck carried on a front end of the shaft, adapted to fit with a tool or tool holder, and a ball cage in the shaft and having a radially extending window. A locking ball os radially displaceable in the window between a holding position engaging in a seat of the tool and a freeing position clear of the seat. An angled surface is engageable radially with the ball, and an actuating rod is axially shiftable and coupled to the cage or to the angled surface. An actuator can axially shift the rod and thereby relatively axially displace the ball and the angled surface and cam the ball with the angled surface into the holding position. A primary spring biases the rod so as shift the ball with the angled surface into the holding position.

Abstract: A modular cutting tool holder portion for a metal-working machine includes a first engagement face configured for clamping engagement with a corresponding second engagement face of a complementary modular cutting tool holder portion. The first engagement face includes a base surface and interlocking elements in the form of exactly four projecting protrusions or exactly four recesses. Each interlocking element includes a non-contact surface spaced from the base surface. The non-contact surface includes two opposing edges between which it extends, and two abutment surfaces each extending from a respective one of the two opposing edges to the base surface and being configured for the clamping engagement.

Abstract: A first coupling part interacts with a second coupling part of a tool coupling. The first coupling part has a first body and a conical pin, which extends from the first body along a center axis (x) to an end surface. The conical pin is insertable into a conical seat. The conical pin comprises a cavity, which extends from the end surface and comprises a number of first protuberances, which are separated and arranged at a distance from each other along a circumferential direction in respect to the center axis so that there are formed a corresponding number of first recesses. The first protuberances form a respective first contact surface and interact with a corresponding number of separated, second contact surfaces of a pull member of the second coupling part. The first contact surfaces form an acute angle with the center axis.

Abstract: A hydraulic coupling system includes an adapter, a shell mill, a threaded member, and a chucking membrane. The adapter includes a tapered pilot disposed on and extending from an end face. The shell mill includes a central counter bore for enabling the pilot of the adapter to be inserted therein. The threaded member includes at least one sealing member and is capable of being threaded into a threaded bore of the shell mill. The chucking membrane includes an intermediate portion disposed between two flanges and forms a fluid-tight channel for hydraulic fluid. The chucking member has a tapered inside surface. When the threaded member is threaded into the shell mill, the tapered surfaces of the pilot and the chucking membrane cause an axial force to seat the end face of the shell mill firmly against the end face of the adapter.

Abstract: A revolver disk (1) for a machine tool with, in the area of the radially extending bore holes (7) for the projection (9) of tool holders (5), a rotary axis of the revolver disk (1) extending parallel and penetrating bores (11) aligned perpendicular in reference to the face, by which a tool holder key (27) is guided. By displacing the tool holder key (27) against the force of a spring (17) the frontal end (25) is inserted into the clamping device in the projection (9) of the tool holder (5) and thus the tool is clamped with it.

Abstract: Provided is an insert that has good positioning precision and sufficient rigidity. Said insert is rod-shaped and has: a shank part; cutting blades formed on both sides of the shank part; and raised surfaces that are positioned between the cutting blades and the shank part and bulge such that parts farther away from the cutting blades are progressively closer to the outer surface of the shank part. In a side view, the rake face of the cutting blade on one side and the raised surface on the other side are disposed in the same direction with respect to the axis of rotation of the shank part.

Abstract: A toolholder assembly for releasably holding a toolholder includes a toolholder having a tubular shank with at least two perforations; a tool support member; a canister disposed within the tool support member and including at least two apertures; a lock rod movable within the tool support member in a reciprocating motion for pulling the toolholder into a locked position and for releasing the toolholder to an unlocked position; and at least two locking elements disposed within the spaced apertures of the canister and engaging the lock rod so that movement of the lock rod causes the locking elements to extend radially outward from the canister. The circumferentially spaced perforations of the tubular shank each include a primary cylindrical wall and a forward facing contact surface at least partially defined by a depression having a converging wall surface non-concentric with the primary cylindrical wall of the perforations.

Abstract: An apparatus for releasably holding a tubular toolholder shank includes a tool support member; a canister disposed within the tool support member; a lock rod movable within the tool support member in a reciprocating motion for pulling the tubular toolholder shank into a locked position and for releasing the tubular toolholder shank to an unlocked position; and at least two locking elements engaging the lock rod so that movement of the lock rod causes the locking elements to extend outward to engage the tubular toolholder shank. The lock rod includes a relief cavity extending rearward from a forward end of the lock rod. The lock rod has a maximum outer diameter and the relief cavity has a maximum diameter. A ratio of the maximum diameter of the relief cavity to the maximum outer diameter of the front portion of the lock rod is greater than approximately 1 to 4.

Abstract: A clamping unit for releasably holding a tubular toolholder shank has a base member with a canister sleeve mounted therein. To secure the canister sleeve within the base member and to minimize movement caused by tolerances, retention bolts are threadably mated within the base member to engage a slot within the canister, wherein the relationship between the retention bolt and the slot is such that the retention bolt is intentionally misaligned, so that when engaged with the canister slot, the retention blot resiliently deflects and provides both an axial force and a lateral force upon a canister sleeve.

Abstract: A tool holder includes a hollow taper shank chucking device having a center axis, a chucking device, a tension rod which cooperates with the chucking device and an actuating unit by means of which the tension rod may be actuated, i.e., displaced. The actuating unit has an actuating element which is movable at an angle relative to the center axis and which includes at least one actuating part. The angle may be 90°. The tension rod is provided with at least one engagement part. The actuating part and engagement part form a wedge mechanism which is used to convert a radial motion of the actuating element, i.e., a displacement perpendicular to the center axis, into an axial displacement of the tension rod in the direction of the center axis.

Abstract: An apparatus for releasably holding a tubular toolholder shank by axially reciprocating a lock rod between a locked and unlocked position. Compression balls following a helical path on a torque nut are used to retract a compression sleeve, which in turn compresses springs against the lock rod to move the lock rod into the locked position. As a result, a repeatable lock rod force is possible with a pre-determined and self limiting rotation of the torque nut. The same helical groove may be used to advance the compression sleeve against the lock rod to urge the toolholder from the base member.

Abstract: A clamping device used for securing a toolholder for metal working operations includes a lock rod reciprocating along a lock rod longitudinal axis to radially activate locking balls to engage perforations within the shank of a toolholder, wherein the toolholder is oriented along a toolholder axis non parallel to the locking rod longitudinal axis. Additionally, the lock rod includes a ramp which engages a bump-off pin in a direction lateral to the motion of the lock rod to provide a mechanism for ejecting the toolholder from the clamping device.

Abstract: A hands-free quick-change air tool configuration for a machining apparatus includes a tool holder configured to receive a normally hand-held air operated tool. The air manifold is operably receptive of the tool holder. A plunger-type seal configuration is operably interconnected to an air supply and is in operable communication with the air manifold. A method for deburring a part in a machining apparatus is included.

Abstract: A connection system which produces an aligned connection between first and second tool parts includes a spigot projecting from the first tool part, and a spigot-receiving recess formed in the second tool part. The spigot and the recess have correspondingly shaped, non-circular cross-sections. The spigot is not oversized relative to the recess, and may be smaller than the recess, so that the spigot can be inserted into the recess without the recess being expanded or the recess being compressed.

Abstract: A tool holder having a number of tool receptacles which are provided in a parent body and into which a respective cutting tool can be inserted with a fastening shank and can be clamped in the tool receptacle via a clamping device. The clamping device in this case comprises a clamping bolt which extends laterally through a bore in the parent body up to the tool receptacle and has at its outer end a bolt head which can be actuated via a setting tool. The bolt head is in this case locked by a locking element which is attached to the parent body in the region of the bore and which forms a stop for the bolt head.

Abstract: A robot controller (7) controlling a robot (1) used combined with a machine tool (5, 6) provided with a communication unit (9) connecting the robot controller to a machine tool, a detection unit (52) detecting through the communication unit a type and number of machine tools, and a setting unit (55) setting the robot controller based on the type and number of machine tools detected by the detection unit. Due to this, machine tool and robot startup work can be simply and easily performed without requiring skill or increasing the startup man-hours. The setting unit selects one setting file from among a plurality of setting files for the robot controller, stored in the robot controller, based on the type and number of machine tools detected by the detection unit.

Abstract: A toolholder assembly for releasably holding a toolholder includes a toolholder having a tubular shank with at least two perforations; a tool support member; a canister disposed within the tool support member and including at least two apertures; a lock rod movable within the tool support member in a reciprocating motion for pulling the toolholder into a locked position and for releasing the toolholder to an unlocked position; and at least two locking elements disposed within the spaced apertures of the canister and engaging the lock rod so that movement of the lock rod causes the locking elements to extend radially outward from the canister. The circumferentially spaced perforations of the tubular shank each include a primary cylindrical wall and a forward facing contact surface at least partially defined by a depression having a converging wall surface non-concentric with the primary cylindrical wall of the perforations.

Abstract: An apparatus for releasably holding a tubular toolholder shank includes a tool support member; a canister disposed within the tool support member; a lock rod movable within the tool support member in a reciprocating motion for pulling the tubular toolholder shank into a locked position and for releasing the tubular toolholder shank to an unlocked position; and at least two locking elements engaging the lock rod so that movement of the lock rod causes the locking elements to extend outward to engage the tubular toolholder shank. The lock rod includes a relief cavity extending rearward from a forward end of the lock rod. The lock rod has a maximum outer diameter and the relief cavity has a maximum diameter. A ratio of the maximum diameter of the relief cavity to the maximum outer diameter of the front portion of the lock rod is greater than approximately 1 to 4.

Abstract: A quick-change tool holder designed to facilitate thread cutting on manual metal cutting lathes. The tool holder mounts on a face of a prior art quick-change tool post that is mounted on the lathe compound rest with a face parallel to the axis of the compound rest and a face perpendicular to this axis and holds the axis of the cutting tool at a particular horizontal angle with respect to the face of the tool post so that, when the compound rest is rotated so as to feed the cutting tool in a preferred direction, the tool axis becomes either perpendicular or parallel to the axis of the work piece to be threaded in the cases of external or internal threading respectively. The threading tool holder also has an external vertical face parallel to the axis of the cutting tool that facilitates setting the angle of the compound rest.

Abstract: A clamping device used for securing a toolholder for metal working operations includes a lock rod reciprocating along a lock rod longitudinal axis to radially activate locking balls to engage perforations within the shank of a toolholder, wherein the toolholder is oriented along a toolholder axis non parallel to the locking rod longitudinal axis. Additionally, the lock rod includes a ramp which engages a bump-off pin in a direction lateral to the motion of the lock rod to provide a mechanism for ejecting the toolholder from the clamping device.

Abstract: A tool-holding device for an insert tool (14) equipped with an at least essentially disk-shaped hub (42), in particular for a hand-guided angle grinder (32) or a hand-guided circular saw, having a drive device (12) that includes a leaf spring unit (58) and is able to clamp the insert tool (14) in the axial direction (64). The leaf spring unit (58) has at least one freely extending spring piece (110) that extends at least partially in the circumference direction (50, 52).

Abstract: A quick change tool holder having a base member, a body, a quick change head member, and a cutting tool cartridge. The base member includes an upper surface, bottom surface, and mating surface and is adapted to removably mount to an associated cutting machine carriage. The body includes an end wall and an inner surface, where the end wall includes a dovetail portion. The body is adapted to engage the base member in an interlocking fashion. The quick change head includes a top surface, a bottom surface, an interface wall having a channel disposed therein, and an outer wall having a plurality of longitudinal grooves, wherein said channel is adapted to receive said dovetail portion. The cutting tool cartridge is adapted to engage the longitudinal grooves of the quick change head.

Abstract: A tool holder assembly includes a tool holder with a shank and a key slot having a surface with an angled portion that forms a non-zero angle with respect to a longitudinal axis of the tool holder assembly. A clamping mechanism includes a support block, a ball canister including a key, and a lock rod. An interference fit key arrangement is provided between the tool holder and the clamping mechanism by an abutment surface located along the first side wall of the key. The abutment surface contacts the angular portion of the key slot to cause the key slot to undergo elastic deformation and allow simultaneous contact between the abutment surface and the angular portion of the key slot and the second side wall of the key and the second surface of the key slot, thereby providing for an interference fit key arrangement between the tool holder and the clamping mechanism when the tool holder assembly is placed in the locked position.

Abstract: A tool holder assembly includes a tool holder with a shank and a key slot having a surface with an angled portion that forms a non-zero angle with respect to a longitudinal axis of the tool holder assembly. A clamping mechanism includes a support block, a ball canister including a key, and a lock rod. An interference fit key arrangement is provided between the tool holder and the clamping mechanism by an abutment surface located along the first side wall of the key. The abutment surface contacts the angular portion of the key slot to cause the key slot to undergo elastic deformation and allow simultaneous contact between the abutment surface and the angular portion of the key slot and the second side wall of the key and the second surface of the key slot, thereby providing for an interference fit key arrangement between the tool holder and the clamping mechanism when the tool holder assembly is placed in the locked position.

Abstract: A tool assembly for a thermoforming machine has a tool holder having an abutment face and a tool having an abutment part. The tool and holder have a groove and a rail fittable in the groove for fitting the tool to the holder into a working position with the abutment part abutting the abutment face. A part-conical seat centered on a tool axis is formed on the tool. A pin formed with a part-conical head face complementary to the seat and centered on a pin axis is carried on the holder. The seat and head are positioned on the tool and holder such that in the working position the axes are generally parallel but slightly offset from each other and the part-conical head face is axially engageable with the seat.

Abstract: The present invention provides a tool holder interchangeably attached to a machine tool such as a combined machining lathe. A combined machining lathe 1 comprises main spindles 20 and 30 for gripping a workpiece, and a machining main spindle head 50 which rotates around a B axis. There are provided stockers S1 and S2 inside the lathe, and tool holders 200 and 300 are respectively stored in the stockers S1 and S2. The tool holder 200 comprises a taper shank portion 230 of a main shaft in a housing 210 and four pull studs PS2 around the taper shank portion 230 of a main shaft, and is gripped by collet chucks of the machining main spindle head 50. Rotation of the taper shank portion 230 of a main shaft is transmitted to a shaft 250 via a gear mechanism, to drive a drill tool 252 to drill a deep hole.

Abstract: The present invention relates to cutting tools and, more particularly, to cutting tools having inserts and insert-receiving recesses with curved surfaces. The cutting tool includes a toolholder having a recess and an insert adapted to be received in the recess. The recess has a top surface with a curved portion, a bottom surface with a curved portion, and a fixed stop surface. The insert has a top surface with a curved portion, a bottom surface with a curved portion, and a stop surface. The curved portion of the top surface of the insert and the curved portion of the bottom surface of the insert are curved such that they abut against the curved portion of the top surface of the recess and the curved portion of the bottom surface of the recess, respectively, when the stop surface of the insert abuts against the fixed stop surface of the recess. The present invention also relates to a cutting tool kit, a cutting insert and a method for positioning an insert relative to a toolholder.

Abstract: The invention relates to an interface between two parts of a tool system, in particular to a metal cutting tool (1). Said interface comprises a holder (3) provided with a cavity (31), an interchangeable head (5) which is arranged on the axial extension of the holder and provided with a projection (33) introducible into the cavity (31) and a clamping device (19) for fixing the interchangeable head (5) to the holder (3). The inventive interface is characterised in that the clamping device (19) is provided with a holding bolt (41) and an eccentric element (21) which axially displaces said bolt and is actuated through a peripheral surface (17) of the metal cutting tool (1).

Abstract: A tool assembly in which a tool is removably secured to a tool holder. A sleeve of the tool is first fitted onto a shaft of the tool holder and then, by symmetrically radially expanding the shaft, the tool is secured to the tool holder.

Abstract: An apparatus is disclosed for releasably holding a toolholder shank having a lockable surface and a releasable surface utilizing an actuating bolt with an associated threaded actuating nut. When the actuating bolt is rotated in a locking direction, the actuating nut is drawn onto the bolt thereby clamping against the lockable surfaces of the toolholder shank. When the actuating bolt is rotated in the releasing direction, a releasing segment acts upon the toolholder thereby ejecting it from the tool support member.

Abstract: The present invention provides an improvement (20) in a Davenport® automatic screw machine having a stationary spindle. The improvement broadly includes a quick-change mechanism (26) associated with the stationary spindle (22). The mechanism includes mating frusto-conical first and second surfaces (28, 31) on the spindle and tool holder, and a multi-lead threaded connection (32) between the tool holder and stationary spindle such that the tool holder may be quickly locked into mating engagement with the stationary spindle by relative rotation therebetween through a short angular distance. The invention may also include an adjustment mechanism (33) that allows the axis (x2—x2) of the tool to be aligned with the axis (x1—x1) of a spaced rotatable spindle. This adjustment mechanism includes a base member (34), an adjustment member (35), and a locking mechanism (37) for selectively holding the adjustment member in the desired position relative to the base member.

Abstract: A toolholder has a conventional square shank body with a pocket extending downwardly from the top surface of the body so that the cutting tip of an insert mounted within the pocket is positioned below the top surface of the square shank body. This permits the pocket to have a back wall through which coolant may be introduced and directed against the cutting insert. Typically, the cutting tip of a conventional square shank toolholder is aligned with the top surface of the toolholder. Additionally, a toolholder assembly is disclosed which includes a plurality of such toolholders.

Abstract: A cutter holder for CNC lathe is disclosed to include a bottom holder block, which is affixed to the frame of a CNC lathe with screws and has a positioning groove with a middle semispherical recess for holding a barrel that holds a tool shank with a front chuck for holding a cutting tool, and a top holding down block, which is detachably affixed to the bottom holder block with screws to hold down the barrel and has a semispherical bottom recess fitting the spherical middle flank portion of the barrel corresponding to the middle semispherical recess of the bottom holder block.

Abstract: A tool clamping device for a tool having a shaft which is accurate to size and which can be inserted into the receiving bore of a tool support, is provided with a clamping device which can be screwed on a screw thread of the tool support while the tool has a ring, which is arranged radially protruding in a clamping area. The ring extends in the circumferential direction and, with the shaft of the tool inserted into the receiving bore, the clamping device is axially supported against the ring (FIG. 2).

Abstract: A toolholder assembly for releasably holding a toolholder at a selected radial location within the toolholder assembly. The toolholder assembly includes a tool support member, an actuating bolt and an actuating centering nut. Rotation of the actuating bolt in a locking direction centers the actuating centering nut, actuating bolt and the toolholder with respect to the radial axis of a bore within the tool support member.

Abstract: A cutting tool system includes a clamping device and a cutting tool mounted therein. The cutting tool carries a cutting edge and includes a shaft clamped within an aperture of the clamping device. Prior to being clamped, the shaft is movable relative to the clamping device in either a longitudinal or rotational direction, in order to locate the cutting edge in a desired position. Either the clamping device or the cutting tool carries a spring-loaded device which engages a recess formed in the other of the cutting tool and clamping device when the cutting tool and its cutting edge are in a desired position, to provide an indication that the cutting tool is in such desired position by providing a sudden increase in a force necessary to displace the cutting tool out of such desired position.

Abstract: A clamping system includes a clamping device that is coaxially located in a receiving section and that extends into the hollow shaft of one piece when two pieces are joined. The clamping system further includes two clamping bodies that can be displaced in opposite directions and an actuating device that drives the clamping bodies. The actuating device displaces the clamping bodies in a synchronous manner into an engaged relation and a disengaged relation with an undercut clamping shoulder of the hollow shaft, whereby a pressure force is applied between the flat surfaces of the two pieces to be connected.

Abstract: A versatile quick change tooling system for internally and externally mounted machine tools which provides components adaptable to a system which is easy to maintain since it has no moving parts. The system would allow for universal adaptation of both internal and external tools on a machine turret and would include a turret having a face portion for mounting tools thereon; a plurality of receivers adjustable to centerline engaged either to the face portion or the perimeter portion of the turret; a tapered bore formed into each of the receivers; a tool holder, with a tool secured to a first end, and having a second end being a tapered shank to be positioned within the tapered bore of each of the receivers; a retainer secured to the tapered shank to secure each tool holder to each receiver; and allowing each of the tool holders mounted to the receivers to be easily removed by unsecuring the retainer from the tapered shank, and replacing the tool holder with a new tool holder and tool secured thereupon.

Abstract: An apparatus is disclosed for releasably holding a toolholder shank having a lockable surface and a releasable surface utilizing an actuating bolt with an associated threaded actuating nut. When the actuating bolt is rotated in a locking direction, the actuating nut is drawn onto the bolt thereby clamping against the lockable surfaces of the toolholder shank. When the actuating bolt is rotated in the releasing direction, a releasing segment acts upon the toolholder thereby ejecting it from the tool support member.

Abstract: A rack including at least one substantially horizontally oriented hanger member. The hanger member defines a cross-sectional profile dimensioned and shaped to fit within the mounting keyway of a standard tool holder thus enabling the tool holder to be suspended, or hung form the hanger member. The rack includes a retention means for inhibiting translational movement of the tool holder along the hanger member.

Abstract: A millin tool holder includes a tool holder body having a tool shank opening. The tool shank has an annular shoulder seated on a shoulder on the tool holder. A pair of confronting slots form an opening for receiving a pin which prevents the tool head from rotating with respect to the body.

Abstract: A clamping chuck having a central receptacle and a disk arranged around the receptacle and which may be moved from a clamping position, whereby a draw bar inserted into the receptacle is clamped, to a releasing position wherein a draw bar is released from being clamped. The disk has a locking mechanism including a plurality of locking elements which are equally spaced in a circumferential direction. The draw bar is coupled to a brake such that the braking force of the brake is proportional to a pull on the draw bar. Thus, a high axial load on the draw bar causes a high braking force and a low load results in a low braking force.

Abstract: An apparatus and method for aligning a clamping unit and a toolholder to facilitate proper positioning of a cutting tool with respect to a workpiece.

Abstract: A tunable toolholder with a dynamic vibration absorber wherein an absorber mass is compressed between two resilient supports utilizing at least one longitudinally movable pressure plate to dynamically tune the toolholder. The pressure plate is displaced by an adjustment screw extending through the front face of a toolholder head removably mounted at one end of the toolholder.

Abstract: A metal cutting tool assembly comprising a rigid holder blade, an insert receiving slot formed in a leading end of the holder blade and defined between a resiliently displaceable clamping jaw formed integrally with the holder blade and rigid base jaw forming part of the holder blade, spaced apart displacement and supporting surfaces respectively formed in or on the clamping jaw and the holder, and a slot opening key, with a pair of spaced apart projecting prongs of the key adapted to engage the surfaces. At least one of the prongs is displaceable with respect to the holder blade so as resiliently to displace the clamping jaw outwardly with respect to the base jaw into an opening position for insertion or removal of an insert.

Abstract: A metal cutting tool assembly comprising a rigid holder blade, an insert receiving slot formed in a leading end of the holder blade and defined between a resiliently displaceable clamping jaw formed integrally with the holder blade and rigid base jaw forming part of the holder blade, spaced apart displacement and supporting surfaces respectively formed in or on the clamping jaw and the holder, and a slot opening key, a pair of spaced apart projecting prongs of the key with adapted to engage the surfaces. At least one of the prongs is displaceable with respect to the holder blade so as resiliently to displace the clamping jaw outwardly with respect to the base jaw into an opening position for insertion or removal of an insert.