SU373400A1 - ALL-UNION I - Google Patents

Description

one

The invention is intended for use mainly in mining machines.

A device for fastening cutting tools, in particular cones, in percussion machines is known to contain its holder and the entrance w, the shank into it, which are interconnected by balls, placed in an annular closed cavity formed by annular grooves of the holder and the shank.

However, the known devices are distinguished by the low reliability of the tool attachment, especially when dynamically acting on it if there is no resistance from the side of the slab. In addition, the contacting surfaces of the tool collar and the tool holder are painted out due to repeated removal of them against each other due to the lack of reliable preliminary pressing of the tool collar to the tool holder.

In order to increase the reliability of fastening in the proposed device, the toolholder and shank grooves are mutually offset axially by на 3 of the ball diameter and each of them is equal to two ball diameters, and the holder is equipped with two spacer screws that interact with the balls and are diametrically opposed.

In this case, the balls, interact with each other, as well as with the walls of the annular pro2

points of the holder and shank, create strut forces in the directions to the holder and to the tool.

FIG. 1 and 2 show the proposed device in different positions.

The tool attachment device comprises a holder J with an inner annular groove 2 and the shank 3 of the tool 4 included in it, having an outer annular

groove 5. Tool 4 is equipped with a flange 6 in contact with the end of the holder /.

In the assembled position, the devices of the grooves 2 and 5 are mutually offset in the axial direction and form an annular cavity 7 filled with balls 8. The axial displacement of the grooves 2 and 5 is equal to Vs of the ball diameter, and the width of each groove is equal to two diameters of the ball 8. The holder / is equipped with two spacers

screws 9 and 10, which are diametrically opposed in the threaded holes 11 and 12, respectively.

The principle of operation of the described device is as follows.

The tool 4 is inserted with its shank 3 into the holder 1 as far as it will go by the collar 6 into its end. Through the hole is NOT the annular cavity 7, the balls 8 fall asleep. Since the grooves 2 5 are mutually offset by / of the diameter of the ball,

balls 8 when filled into the annular cavity 7

are staggered with a mixture of their axes in / out of their diameter.

When tightening the spacer screw 9, the balls 8, interacting with each other, as well as with the walls of the annular grooves 2 and 5 of the holder / and the tool 4, create a thrust force, with one row of balls 8 acting on the shank 3 in the direction of the holder /, and the second - on the holder / in the direction of the tool 4. This creates a preliminary preload of the collar 6 of the tool 4 to the holder 1, the preload force can be adjusted with screws 9 and 10.

When disassembling the tool 4, the disassembly of the proposed device is dried; the following procedure is established: screw 10 is unscrewed and balls 8 through hole 12 are pushed out of the annular cavity 7 by the action of screw 9.

Subject invention

A device for fastening an instrument in percussion machines, comprising a holder and a shank included therein, interconnected by means of balls, which are located in a cavity formed by annular grooves of the holder and shank, characterized in that, in order to increase the reliability of fastening, the grooves are mutually they are axially displaced to / from the diameter of the ball and each of them is equal to two ball diameters, and the holder is equipped with two spacer screws that interact with the balls and are diametrically located opposite.