SU1537419A1 - Chuck for broaching - Google Patents

Abstract

The invention relates to the field of machine tools and can be used in pulling machines. The aim of the invention is to improve the reliability and quality of processing by eliminating breaks of the draw and reducing the shock load on the tooth of the draw. The chuck body consists of a shank 1 and a sleeve 2. In the sleeve 2 are placed the cams 3, which are spring-loaded at the expense of springs 5 and stops 6. Springs 8 are placed between the sleeve 2 and the thrust washer 7. The thrust washer 7, springs 8 and the hub 2 are connected to the shank 1 with screws inside the sleeve 10, spring-loaded by the springs 11 and the casing 12. The contact between the cams 3 and the sleeve 10 is carried out by means of the rocker arms 13 with the balls in order to prevent friction on the mating surfaces. In the sleeve 10, an annular groove 16 is formed, and in the sleeve 2, a radius groove, into which the radius protrusion 15 of the rocker arm 13 enters. As the stretch 4 dulls during operation, the cutting force increases dramatically. At the same time, the springs 8 are compressed to the maximum value due to the action of the shank of the shank 4 through the cams 3 and the sleeve 2. The edge of the annular groove 16 of the sleeve 10 is located behind the axis of the radius protrusion 15 of the rocker arm 13. The cams 3, turning the rocker arm 13, expenditure the end shank 4 is released. 3 il.

Description

The invention relates to a machine tool industry and can be used in pulling machines.

The purpose of the invention is to increase the reliability of work and the quality of processing by eliminating breaks in the course of drawing and reducing the impact load on the teeth.

FIG. 1 shows the cartridge in the closed position, a longitudinal section; in fig. 2 is a section A-L in FIG. one; in fig. 3 - cartridge in open position, longitudinal section. “

The body of the cartridge is made detachable and consists of a shank 1 and a sleeve 2. Shank 1 of the body serves to fasten the cartridge in the machine slide. Cams 3 are placed in the sleeve 2, which serve to grip the stem of the broach 4 and are in the spring-loaded state by means of the springs 5 and the stops 6. Springs 8 are installed by the packings in the sleeve 2 and the thrust washer 7. The number of springs 8 depends on the critical cutting force at which the break of the end shank 4 occurs. In this case, the force of the allowable total deflection of the springs 8 should be somewhat less than the critical cutting force. The thrust washer 7, the spring 8 and the sleeve 2 are connected to the shank 1 by screws 9 and placed inside the movable sleeve 10. Moreover, the sleeve 10 is spring-loaded due to the springs If and the casing 12. Contact between the sleeve 10 and the cams 3 is carried out by means of the rocker arms 13 with the balls 14 serving to improve the smoothness of the sliding of the liner 10 over the rocker arms 13 and to eliminate nadirov. The rocker arms 13 have the ability to rotate, for which the sleeve 2, which is in contact with the rocker arms 13, has a radius groove, into which the radius protrusion 15 of the rocker arms 13 enters, and in the sleeve 10 there is an annular groove 16.

Parron works as follows.

When the cartridge moves to the left, the sleeve 10 runs over a stop (not shown) and stops. The body with the sleeve 2 and the support washer 7 for some time continues to move, compressing the spring 11. The edge of the annular groove 16 of the sleeve 10 goes beyond the axis of the radius of the protrusion 15 of the rocker arm 13, allowing it

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turning. The cams 3 under the action of the springs 5 abut against the rocker arms 13 and, turning them, disperse, releasing the shank of the pull-rod 4. When the cartridge moves to the right, the sleeve 10 comes off the stop and, moving along the body under the action of the springs 11, through the annular groove 16 of the rocker arms 13 causes the cams 3 to move, clamping the shank of the stitch 4. During the cutting process, since the cutting force is always variable, the shank of the stitch 4, acting through the cams 3 and the bushing 2 on the springs 8, causes them to compress and open, smoothing the oscillations of the force cuts and those m most improving the smoothness of the work. As the cutting 4 becomes blunt during operation, the cutting force rises sharply, threatening to reach a critical value at which the cutting shank 4 can break. At the same time, the springs 8 are compressed to the maximum value due to the impact of the shank 4 through them on the cams 3 and sleeve 2. In this case, the edge of the annular groove 16 of the sleeve 10 is located beyond the axis of the radius of the protrusion 15 of the rocker arm 13, opening the possibility of the latter turning. As a consequence, the cams 3, resting against the rocker arms 13 and turning them, are diverted and the shank of the route 4 is released. This eliminates breakage of the broach 4.

After replacing broach 4 with a new cartridge, it returns to its original position and, capturing a new shank, continues to work, without requiring any additional tweaking operations.

Claims (1)

Invention Formula A cartridge for cams, including a body with cams and a sleeve with a bearing washer, while the cams are spring-loaded in the radial direction relative to the body, characterized in that, in order to increase the reliability of work and quality of processing, rocker arms and springs are inserted into the cartridge, and the body is made of a composite shank and sleeve, while the cams and rocker arms are installed in the sleeve, and the springs are placed between the bearing washer and the sleeve. 77 / U /, / TAW sS5  ///////////////////// &  ttt ///// l FIG. 2 Fig.Z