A stair form member attached jaw is installed with the stair form member provided at the bottom face of the soft jaw. The stair form member is held between a pair of grips in the jaw installing groove of the master jaw from both sides of the radial direction, thereby pulling the stair form member to the bottom direction of the jaw installing groove. The position of the radial direction of the soft jaw is determined by the engagement between the bottom face of the soft jaw and the upper serration faces of the master jaw; and the position of the soft jaw in the tangent line is determined by the close contact of the stair form member to the side face of the jaw installing groove.

Intrusion of chips is prevent into gaps formed between inner end surfaces of master jaws and a chuck cover. A top plate is disposed at the center of an end surface of a chuck body. Top covers, which move in conjunction with movements of master jaws when opening and closing the chuck, are disposed in top cover guide recesses formed at three positions on the top plate. Each top cover abuts the center-side end parts of serrated surfaces formed on both widthwise sides of a respective master jaw and the center-side end part of a step section of a stepped claw therebetween, and the top covers close gaps formed at the center-side end parts by the movements of the master jaws at all times by moving in conjunction with movement of the master jaws.

A wheel spraying protection device is composed of a hollow mounting rack, an electric cylinder, a tray, an electromagnetic chuck, a sleeve, a piston, a soft rubber cover, a support column, an end cover, high temperature resistant plastic protective plugs, springs and iron posts. The device can play a role in protecting during a wheel spraying process, and solves the problem that a flange face, a center hole and bolt hole conical surfaces are adhered with paint. The device has the characteristics of advanced process, easiness in manufacturing, simple structure, strong function and the like.

A wheel spraying protection device is composed of a hollow mounting rack, an electric cylinder, a tray, an electromagnetic chuck, a sleeve, a piston, a soft rubber cover, a support column, an end cover, high temperature resistant plastic protective plugs, springs and iron posts. The device can play a role in protecting during a wheel spraying process, and solves the problem that a flange face, a center hole and bolt hole conical surfaces are adhered with paint. The device has the characteristics of advanced process, easiness in manufacturing, simple structure, strong function and the like.

A drill chuck having a chuck body, having a clamping sleeve with a conical basic shape that can rotate about the chuck axis of the chuck body, by the rotation of which clamping sleeve a plurality of clamping jaws can be moved relative to the clamping body. The clamping sleeve is made in two parts, having a conical, metallic outer sleeve, having a conical, inner sleeve made of plastic, wherein the outer sleeve has a cylindrical subsection on its inner circumference for radial centering of the outer sleeve on the inner sleeve. A clamping sleeve and a method for producing knurling on the clamping sleeve are also provided.

A stair form member attached jaw is installed with the stair form member provided at the bottom face of the soft jaw. The stair form member is held between a pair of grips in the jaw installing groove of the master jaw from both sides of the radial direction, thereby pulling the stair form member to the bottom direction of the jaw installing groove. The position of the radial direction of the soft jaw is determined by the engagement between the bottom face of the soft jaw and the upper serration faces of the master jaw; and the position of the soft jaw in the tangent line is determined by the close contact of the stair form member to the side face of the jaw installing groove.

The invention relates to a tool holding device comprising a tool holding body for securing, in a fixed manner, a rotary tool comprising a shaft, provided with a clamping section and a receiving opening for the shall of the tool, a coolant feeding device for pressurized fluid, at least one coolant guiding device for guiding the coolant into a clamped tool shaft. The coolant guiding device is designed as at least one flat groove on an inner side of the receiving opening, joining to the front side on a free end of the tool holding body and directly adjacent to the tool shaft in the surroundings of the tool holding device or a coolant storing chamber and or collecting chamber is provided in the region of the free end of the tool holding body, to which the at least one coolant guiding device joins. The coolant storing chamber and or collecting chamber is connected by means of an annular gap to the surroundings of the tool holder device. The coolant storing chamber and/or collecting chamber and the annular gap are defined at least partially by the work shaft.

A drill chuck has a chuck body having a plurality of angularly spaced and axially extending but angled guide grooves each holding a jaw that is axially displaceable between an axially front closed position and an axially rear open position. Each jaw has an outer edge formed with external teeth, and also has an axially rearwardly directed rear face extending at an acute angle to a plane perpendicular to the axis. A ring rotatable on the body about the axis has an internal screwthread meshing with the teeth, and an adjustment sleeve rotationally coupled to the ring is rotatable to move the jaws between the open and closed positions. A cover disk on the rear end of the body is formed with respective throughgoing chip-discharge holes each having an inner end aligned with a respective one of the grooves and an outwardly open outer end.

The invention relates to a tool holding device comprising a tool holding body for securing, in a fixed manner, a rotary tool comprising a shaft, provided with a clamping section and a receiving opening for the shall of the tool, a coolant feeding device for pressurized fluid, at least one coolant guiding device for guiding the coolant into a clamped tool shaft. The coolant guiding device is designed as at least one flat groove on an inner side of the receiving opening, joining to the front side on a free end of the tool holding body and directly adjacent to the tool shaft in the surroundings of the tool holding device or a coolant storing chamber and or collecting chamber is provided in the region of the free end of the tool holding body, to which the at least one coolant guiding device joins. The coolant storing chamber and or collecting chamber is connected by means of an annular gap to the surroundings of the tool holder device. The coolant storing chamber and/or collecting chamber and the annular gap are defined at least partially by the work shaft.

a dust collector for electrical drill, comprising: a sleeve portion, a supporting portion, and a dust collecting portion; the sleeve portion disposed in front of the fixing part of the electrical drill; the supporting portion coupled with the sleeve portion, and surrounding and isolating a rotating part of the electrical drill; the dust collecting portion coupled with one end of the supporting portion and covered the drill bit; the dust collecting portion including a telescoping sleeve body and a spring. Besides, the dust collector adds a stop device which comprises a ruler paralleled to the dust collection portion and a stopper disposed in the outside of the supporting portion, whereby collecting the dust when drilling operation and controlling precisely the drilling depth.