SU1549729A1 - Honing head for machining blind holes - Google Patents

Abstract

The invention relates to mechanical engineering and can be used in honing blind holes. The purpose of the invention is to increase the reliability of the honing head. With the approach of hone to the bottom of the blind hole, the pushers 13 act on the end of the workpiece. The axial force on the zone increases and the spring 17 begins to compress, and the case 1 with abrasive bars 8 receives an axial displacement equal in magnitude but reversed in the direction of the speed of the reciprocating movement of the spindle at some specific length in accordance with the setting of the machine. When the spindle 14 moves upward due to the elastic forces of the spring 17, the body 1 with the pads 7 and the bars 8 is held in the lowest position, and after the elastic recovery of the spring 17, the hone moves upward with a given speed of reciprocating movement. 2 Il.

Description

The invention relates to mechanical engineering and can be used in honing blind holes.

The aim of the invention is to increase the reliability of the honing head.

FIG. 1 shows the honing head, general view; in fig. 2 is a diagram of the trajectories of bar grains on the scan of the hole being machined.

The honing head includes a housing 1, inside which in the central bore 2 there is mounted an axially movable rod 3, including a piston 4 with rubber sleeves, expansion cones 5, 6. Pads are installed in the radial windows of the housing 1.

7 fasten the abrasive bars 8.

8 threaded grooves of housing 1 are fitted with threaded plugs 9 and 10.

At the end of the plug 9, the spring 11 of the stem 3 is installed. The upper part of the spring 1) enters the opening 12 at the end of the expanding rod 3. At the lower end of the housing 1 are installed the pushers 13 made of hard alloy or superhard material. The protruding parts of the followers 13 are made radial to reduce the area of contact with the workpiece. The upper part of the body 3 is axially movable relative to the spindle 14 and connected to it by means of the splines 15, the body 1 is fixed in the lower position relative to the spindle 14 by means of a locking ring 16 and is pressed against its end by a spring 17 in contact with the upper end of the groove 18 spindle 14. In the central hole of the screw plug 10 a fitting 19 is installed, on which a flexible hose 20 is fixed to supply the working agent to the central hole 2 of the housing 1.

The second end of the flexible hose 20 is removed from the spindle and can be connected to the fitting of a hydraulic or pneumatic supply coupling. The pads 7 for fastening the abrasive bars 8 are made with slots 21 for the annular springs 22, which ensure that the pads 7 are kept in the windows of the housing 1 in an idle state,

The device works as follows.

A cone rotary head is installed on the machine spindle and inserted into

machined hole. A rotational and reciprocating motion is communicated to the tool, and a working agent is fed under pressure through the hose 20 into the cavity of the central bore 2. The latter, acting on the piston 4, moves the Itok 3 with expansion cones 5, 6 in the axial one, and the pads 7 with abrasive bars 8 in the radial direction. As a result, the bars 8 are pressed against the workpiece surface.

With the approach of hone to the bottom of the blind hole, the pushers 13 act on the end of the workpiece. The axial force on the honing head increases and reaches such a value when the spring 17 begins to compress, and the body 1 with abrasive bars 8 receives a displacement equal in magnitude but opposite in the direction of the speed of the reciprocating movement of the spindle. correspond to the setting value, after which the cam of the reverse reciprocating movement is triggered up. When moving the spindle 14 up due to the elastic forces of the spring 17, the housing 1 with the pads 7 and the bars 8 hold with at the lowermost position, i.e. The hone has an additional movement equal in magnitude but opposite in the direction of the reciprocating movement of the hone. After elastic recovery of the spring 17 o, it does not interfere with the tool moving upward at the speed of reciprocating movement set by the machine. As a result of the tool operation described, bar 8 (FIG. 2) moves from position I to position II, and the cutting abrasive grains describe path III. Similar trajectories describe cutting grains and other hone bars.

Similar actions occur with each approach to the tool to the bottom of the hole in the workpiece. This ensures uniform conditions of operation of the abrasive bars in the bottom part of the blind hole and reduces the height of the periodic errors in the shape (waviness) of the cross section, and at the same time the cone-shape.

After the hole has been machined, the working pressure is shut off.

The spring 11 raises the expanding rod 3 upward, and the annular springs 22 compress the pads 7 with abrasive sticks 8, the diameter of the hone decreases and it is inserted out of the hole.

Claims (1)

The use of the proposed honing head improves its reliability by eliminating the impact interaction between the bottom of the hole and the abrasive sticks. Invention Formula Honing head for machining blind holes containing 497296 casing with expanding cone and holders of abrasive bars installed with axial displacement relative to the casing, characterized in that, in order to increase the reliability of the head, it is equipped with pushers intended for contact with the bottom of the blind bushing and mounted at the end of the casing in a plane parallel to the plane of the ends of the abrasive bars. Compiled by V. Kravets Editor M, Bandura Tehred L. Serdkzhova Order 234 Circulation 600 VNIIPI State Committee for Inventions and Discoveries at the State Committee on Science and Technology of the USSR 113035, Moscow, Zh-35, Raushsk nab. 4/5 t well FIG. 2 Proofreader V.Kabatsiy Subscription