There is provided a undercutting boring tool (10) comprising a bar body (11). A lost motion link consists of a spring (26) selectively compressed by a lost motion rod (27) having a lost motion slot (33) spaced from a drive pin (34). An operating rod portion (36) has a trunnion body (37) at its front end having a pin (41) adapted to engage the lost motion slot (33). A tool carrier (42) forms a pair of spaced flat tines (43) and forms a bearing surface (44) in the bight. The upper tine (43) and the bearing surface (44) section are slotted at (45) to allow the passage of a control link (46). Apertures (47) in the tines (43) engage pins (50) on the trunnion body (37). The bar of a generally H-shaped tool assembly (52) comprises a bearing surface (53) running in the bearing surface (44). A crank portion (54) is connected to the control link (46) via crank pin (55). Drive pins (61) and (62) engage the tool assembly (52) with the end face of the bar body (11) providing positive engagement resisting rotational forces in use. The arrangement allows for post-insertion rotation of the tool assembly (52) from an aligned to a transverse (working) position before engagement of the drive pins (61) and (62).

The invention provides a toolholder matched with the internal jet cooling spindle for cryogenic coolant. The toolholder is mainly composed of a hollow toolholder body, a high-performance thermal insulation structure and a bidirectional sealing structure. They can guide the cryogenic coolant from the spindle to the internal cooling channel of tool and realize the cryogenic thermal insulation and dynamic sealing. The high-performance thermal insulation structure inside the toolholder employs the material with a low thermal conductivity and a low linear expansion coefficient to restrain the low temperature impact of cryogenic coolant on the toolholder and spindle, to ensure the dimensional accuracy and assembly accuracy of the toolholder. The bidirectional sealing structure in the toolholder uses the ultra-low temperature resistant seal rings to prevent the cryogenic coolant from leaking towards the spindle and the tool, to ensure the stability of the coolant transport.

A tool holder with a main part, a deformable receiving portion for clamping a tool, and at least one blocking element which is designed to engage into a corresponding counter element on the tool in order to prevent the tool from moving axially out of the tool holder. The at least one blocking element is integrally formed with the receiving portion. A clamping system having such a tool holder and a method for producing a receiving portion for such a tool holder are also described.

A rotary tool for machining workpieces, said tool comprising a base body having a clamping section and a tool head comprising a cutting region having at least one cutting edge. The tool head comprises at least one coolant channel for supplying a cooling and/or lubricating fluid into the cutting region. At least some sections of the coolant channel have a cross-section that tapers in the direction of the tool head. In this region, at least two coolant outlet lines branch off from contact points of the coolant channel in the direction of the tool head upper surface, and are offset in the axial longitudinal direction of the coolant channel. Also, a production method for a rotary tool, in which the blank of the tool is produced by a sintering method in which the coolant channel of the tool is formed integrally in the sintering method at the same time.

A drill including a drill spindle capable of driving a cutting tool in movement. The drill has at least one channel for distributing a lubricant to the cutting tool, a pump to supply the channel with lubricant and control element(s) for controlling the flow rate of the pump. Such a drill further has mechanical element(s) for determining at least one piece of information representing the torque exerted on the spindle along its axis during drilling. The control element(s) act on the flow rate of the pump as a function of the torque exerted on the spindle along its axis during drilling.

A collet includes an axially rearward end and an axially forward end; a nose portion; a body portion having an outer surface and an inner surface for engaging a shank of a tool; a plurality of slots extending from the inner surface to the outer surface; and a plurality of coolant channels disposed within the collet between the plurality of longitudinally extending slots and extending entirely from the axially rearward end to the axially forward end of the collet. Slots include a first slot extending from the axial forward end to within an intermediary zone, a second slot extending from the axial rearward end to at least the tool holder engagement zone such that the second slot does not intersect the first slot, and a third slot from within the tool engagement zone to within the intermediary zone such that the third slot circumferentially overlaps the first and second slots.

An insert adaptor for parting off including an adaptor index axis and parallel adaptor first and second sides connected by an adaptor peripheral surface which extends peripherally around the adaptor. The adaptor peripheral surface is formed with at least three pockets and bearing surfaces extending between the pockets. Each of the pockets comprises resilient upper and lower clamp surfaces.

For an internal cooling system for precision turning and a control method thereof, internal cooling channels are machined in turning tool, and internal cooling sleeves are used to realize the communication between each hydraulic branch circuit and internal cooling channels of turning tool; a tool contact area calculation model is established to master the change rule of the contact state in whole-domain turning process of a curved surface component; the temperature and flow rate of a cooling medium at a liquid outlet of an air-cooled water cooler are set according to the material property and cutting conditions of the curved surface component; an electromagnetic control circuit is used to control the on-off of electromagnetic directional valves, so as to adjust the conduction sequence and action time of each hydraulic branch circuit, and further realize the localized, directional and accurate cooling of a curved surface component cutting tool.

A lubricant material for assisting machining process comprising a polyethylene oxide-polypropylene oxide copolymer having a weight average molecular weight of 5.010.sup.4 or more and 2.010.sup.5 or less.

A cutting insert includes a cylindrical body portion, a cutting portion, a first fitting portion, a second fitting portion, and a third fitting portion. The cutting portion includes a rake face and a flank face. A ridgeline between the rake face and the flank face constitutes a cutting edge. When viewed in the axial direction, the cutting portion is provided opposite to the third fitting portion relative to the insertion hole. When viewed in the axial direction, a straight line extending through an outer circumferential end of the cutting edge and a center of the insertion hole overlaps with the third fitting portion and is located between the first fitting portion and the second fitting portion. A third central angle is smaller than a first central angle and is smaller than a second central angle.