RU1796352C - Double-jaw chuck - Google Patents

Abstract

Usage: in devices for machine tools of a turning group, when processing bevels on flat parts. SUMMARY OF THE INVENTION: Two cams 2 and 3 are installed in the housing 1, one of which is located in an inclined groove. The cams move from the screw 4. On the working ends of the cams, mounting surfaces are arranged in a plane extending at an angle of 45 °. to the axis of the groove of one of the cams. At the base of the cam 3 there is a cavity in which the nut 9 is located, mounted on the screw 4. The nut is mounted with the possibility of axial and radial movement. 2 ill.

Description

The invention relates to devices used on lathes of a turning group, and can be used when machining bevels on flat parts, for example at the ends of mounting washers.

The aim of the invention is to eliminate these drawbacks and expand the technical capabilities of fastening similar parts in a wide range of sizes when machining bevels.

FIG. 1 shows a section AA in FIG. 2; in FIG. 2 - cartridge, front view.

The cartridge includes a housing ending with a shank 1. In the same plane of symmetry of the housing there are two T-grooves: one perpendicular to the axis of rotation of the housing, and the second inclined relative to the first by an angle corresponding to the angle of the bevel, for example, an installation washer (in the description the notation of this angle is conventionally adopted - a). Cams 2 and 3 are placed in the T-grooves of the housing, kinematically connected by thread sections of screw 4 with different cutting directions. The cam 2 is radially movable in the first groove, and the cam 3 in the second groove. The steps are made from the outer end surfaces of the cams (the workpiece is installed in them). The inclination of these steps relative to the normal, passing at an angle of 45 ° to the plane of symmetry of the T-groove (first and second) and the axis of rotation of the cartridge, corresponds to the angle of the bevel of the part. (Washers). T-grooves in the housing 1 are made with the condition that the cam 2 can be moved perpendicular to the axis of rotation of the cartridge, and cam 3 at an angle equal to the angle of the machined bevel of the part (a - a - in Fig. 1) relative to the direction moving the first cam. The movement of the cam 3 in the inclined groove ensures that the flatness of the mounting surfaces of the ledges of both cams is achieved at any distance between them. By moving the cams 2 and 3 relative to each other, a predetermined bevel angle is maintained for any size of the workpiece:

and "i arctg (-) const,

where a is the angle of the bevel of the workpiece; a - the size of the face of the workpiece located against the specified bevel angle (a):

c is a projection of the bevel plane being machined adjacent to a given bevel angle (a);

p is the rate of change in the size of the processed face in the range of sizes.

The position of the screw 4 relative to the housing 1 is fixed by a strip 6, which forms a bearing with a protrusion in the housing 1, which mates with its surface to the cylindrical section of the screw 4. The strip is attached to the housing 1 by screws 7. For the cam 3 to move freely, it is equipped with a sliding bearing 8 (insert from

5 non-ferrous metal or alloy), and passing through the slots in the cam cavity 3 - nut 9 (rectangular cross-section), which can easily move relative to the inner cavity of the cam

0 thanks to its installation in the bearing 10. Due to this arrangement of the screw 4 and nut 9, the cam 3 relative to the first one has two degrees of freedom of movement (in the direction of the axis of the screw and perpendicular to 5 l), and relative to the second one degree of freedom of movement (in perpendicular to the axis of the nut). For reliability of fastening of workpiece installed in cams 2 and 3

0 (washers) 5 the walls of their ledges are made with a slope of (90-5) 0 with respect to the installation planes m. The operation with the cartridge used is as follows.

5, the workpiece (mounting washer) is moved into the ledges of the cams 2 and 3; 5. By rotating the screw, the cams are moved to the position necessary for its orientation. In this case, a change in the initial position of the cam 3 will be characterized by:

n I

h / Ptg a-idn, mm

n 0 ..

5 where R. is the thread pitch of the screw (mm); n is the number of revolutions of the screw to achieve the required distance between both cams; u - the angle of inclination of the T-shaped groove for the hollow cam 3 relative to the second groove with

0 cam 2.

By rotating .screw 4, centering and reliable fastening of the workpiece-washer by 5 cams of the cartridge is achieved,

5 The presence of a mechanism for fixing the position of the workpieces (mounting washers), consisting of interconnected elements, provides increased productivity and improved quality when processing bevels.

Claims (1)

SUMMARY OF THE INVENTION Two-jaw chuck, in the radial grooves of the casing of which cams are mounted, connected to a drive of their movement, made in the form of a screw, characterized in that, in order to expand technological capabilities by attaching parts such as oblique washers of various sizes, mounting cams are made on the working ends of the cams surfaces located in a plane passing at an angle of 45 ° oblique groove of one of the cams, while at the base of this cam there is a cavity designed to be placed in it a second device, and situated on the screw nut bearing mounted for axial and radial displacements. N