SU757259A1 - Automatic centre chuck - Google Patents

Description

The invention relates to a machine tool, in particular to clamping devices, and can be used for fastening parts such as rotation bodies when machining on lathes in centers.

The automatic drive cartridge is known, in the case of which eccentric self-wedging spring-loaded cams are installed, the center and drive of the cams, made in the form of gear racks interconnected with gear shafts [1].

This device is closest to the invention of the technical essence and the achieved result.

A disadvantage of the known construction is that the changeover of cartridges to the clamping of another type of parts is carried out by replacing the cams, which is laborious and time-consuming, an operation that does not provide a significant increase in the range of diameters of the parts to be fixed. The placement of the drive elements of the rotation of the clamping eccentric cams at the front center of the machine affects the accuracy of machining the part.

2

To expand the technological capabilities of the powered cartridge, the proposed cartridge is equipped with sliders, in which the cam rotation drive is placed, and fic. springs consisting of spring-loaded

₅ sleeves with a pivot arm, one shoulder of which is in contact with the camshaft drive rack.

FIG. 1 shows the proposed cartridge, a general view; in fig. 2 - section A — A in FIG. one; in fig. 3 - section B — B on U fig. one; in fig. 4 - view of the adjustable slide with eccentric clamping cams.

The cartridge consists of a housing 1, which houses the center 2 and the toothed rails 3, which are slidable with the sliders 4 and 5, and on each of them axial eccentric cams 7 are mounted on the axes 6. The axles 6 are preloaded with springs 8. The axes 6 are hingedly connected gear shafts 9, which are coupled with the teeth of 20 rails 10.

Reiki 10 are moved by levers 11,

mounted on the axles 12. The levers And rotate around the axes 12 under the influence of the ends 13, pressed by the springs 14,

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clamps 15. The eccentric clamping cams 7 are pressed against the surface of the workpiece spring-loaded pushers 16.

In the radial direction, the workpiece 17 is based on the rear center 18 of the machine tool and the front center 2 cartridges. In the linear direction, the blanks are based on the spherical stop 19 installed in the housing 1.

The proposed device works as follows.

In the initial position, the eccentric cams 7 are in the “detail unclasped” position and are held by the clips 15. The ends 13 of the clips 15 are in contact with the surface of the small lever arm 11. The pusher is in the cocked state.

After installing components in the centers of HA _n rank its movement under the force developed rear center. The workpiece 17 at the end of its stroke acts on the ends of the clamps 15, moving them and compressing the springs 14. A gap forms between the surface of the small arm of the levers 11 and the end 13 of the clamps 15.

The length of the clamps 15 is chosen such that at the time of the detailing on the support 19, the clamps 15 come out of engagement with the eccentric clamping cams 7, which, under the influence of spring-loaded pushers 16, turn and tighten against the surface of the workpiece 17. Together with the clamping eccentric cams 7, the gear shafts turn 9, by moving the associated rails 10, which, acting on the surface of the large arm of the levers 11, rotate them around the axes 12, choosing a gap between the end 13 of the clamps 15 and the surface th small shoulder arms 11 urge the eccentric cams After 7 to the surface of the workpiece 17, the rotation of the spindle is activated, and at the initial moment a cutting process occurs between the clamping wedging parts eccentric cams 7.

Unclamp the parts in the following order.

The part moves in the centers - moves away from the stop 19, thereby freeing the clamps 15 with compressed springs 14. The moving clamps 15 and the ends 13 rotate the levers 11 around the axes 12. The levers 11 move the associated gear racks 10, which rotate the gear shafts 9 with the hinge clamping eccentric cushions fixed on them 7. The eccentric clamping cams 7 move away from the surface of the workpiece 17, releasing it, and compress the pusher springs 16. The fixture is ready for the next part. ^;

The proposed cartridge allows you to handle a wide range of blanks, increases the utilization rate of equipment due to the reduction of time for clamping blanks in the device.

Claims (1)

Claim ' Automatic drive cartridge, in the case of which eccentric self-wedging spring-loaded cams are installed, has a center and a cam rotation drive, made in the form of toothed racks interconnected with gear shafts, characterized in that, in order to expand the technological capabilities of the cartridge, it is equipped with sliders in which a cam rotation drive is placed, and clamps consisting of a spring-loaded sleeve with a rotary lever, one arm of which is in contact with the cam rotation drive gear.