SU804418A1 - Pneumatic hammer - Google Patents

Description

(54) PNEUMATIC HAMMER

The invention relates to a handheld pneumatic hammer having a vibration-proof body, and can be used in the mining industry, in construction and engineering. Known pneumatic hammer containing a cylinder, stepped drummer and air distribution device with a valve L1J. The lack of a hammer is an unstable mode of operation with varying rebound coefficients of the hammer from the tool. The closest in technical essence to the present invention is a pneumatic hammer comprising a housing with channels for supplying and discharging compressed air, a working tool, a three-stage spool with control channels and a stepped impactor separating the housing cavity to the front working chamber, exhaust chamber and the rear working chamber is permanently connected to the air duct 12J. The disadvantage of this pneumatic hammer is the inconvenience of the operator pressing the body on the hammer body. The purpose of the invention is to provide constant force of pressure of the operator on the body of the hammer. This goal is achieved by having a channel in the housing that connects the rear working chamber with the air supply main and the anterior chamber through the cavity of the middle part of the spool, the end cavities of the spool are alternately connected via control channels to the rear and front chambers and the exhaust chamber, and the drummer is made three-stage, the diameter of the rear tread which is larger than the diameter of its middle tread, but less than the diameter of the front tread. The drawing shows the concept of a pneumatic hammer. The pneumatic hammer contains a two-stage case 1 in which the shank 2 of the working tool is located, a three-stage drummer having a front stage 3 and a rear stage 4 connected by a middle stage 5. The rear end of the rear stage 4 and the inside surface of the case 1 are formed by a rear working chamber 6, constantly the channel 7 is connected to the air supply line 8.

The front end of the front stage 3, the shank 2 of the tool and the inner surface of the housing 1 is formed by the front working chamber 9. The transitional part 10 of the inner surface of the housing 1 and the middle level 5 of the striker formed an exhaust chamber 11 for exhausting air from the outer end cavities of the three-step spool 12, air distribution device.

The spool 12 with its right end cavity is connected by channel 13 for controlling the return stroke of the striker through window 14 to chamber 6, and for its left end cavity - by channel 15 for controlling the forward stroke of the impactor through window 16 for camera 9.

Windows 14 and 16 are windows of the extreme positions of the drummer and perform feedback along the way.

Chamber 9 during the return stroke of the striker channel 17 is connected to the inlet cavity 18 of the spool 12, as well as to the air supply channel of the Vis chamber b or to the outlet cavity 1U of the spool during the forward stroke of the striker. Chamber 11 has an exhaust port 20 for discharging air from channels 13 and 15 into the atmosphere. Double arrows indicate the path of compressed air during forward and reverse strokes (drummer).

Pneumatic hammer works as follows.

Compressed air from the air supply line through channel 7 is supplied to chamber b, where a constant pressure is maintained equal to that of the pipeline. The drummer moves downward under the action of air pressure in chamber 6, opens the window 14 with the rear end of its rear stage 4, causing at this moment a blow by the front stage 3 on the tool 2 shank.

Compressed air through the window 14 and the channel 10 from the chamber 6 enters the right end cavity. The thrusting valve 12 and throws it to the left, displaces the air from the left front spool through the channel 15, window 16, chamber ii and window 20 into the atmosphere.

The pressure of the compressed air through the cavity 18 of the spool 12 through the channel 17 is supplied to the chamber 9. In chamber b, crk and in chamber 9, while maintaining a pressure equal to the main pressure.

At the end of the reverse stroke of the drummer, the front end of the front stage 3. | opens window 16, and the front end of the rear stage 4 opens the window

14, chamber 11 and window 20 into the atmosphere. Compressed air from chamber 9 through window 16 through channel 15 enters the left, end cavity of spool 12 and transfers it to the right. In this case, the spool interrupts the supply of compressed air into the chamber 9 and connects it through the channel 17c with the exhaust cavity 19 of the spool, with the atmosphere. The return stroke is stopped and the working stroke begins,

5 A pneumatic hammer ensures the stability of the operator’s pressing force and fulfills the necessary vibration protection requirements of the operator.

Claims (2)

Invention Formula A pneumatic hammer comprising a housing with channels for supplying and from 5 compressed air, a working tool, a three-step spool with control channels and a stepped hammer that separates the body cavity to the front working chamber, chamber, vy. a clap and a rear working chamber, permanently connected to the air duct, characterized in that, for the purpose of provision. operator force pressures , on the hammer body, in the body there is a channel connecting the rear working chamber with the air supply line and the front working chamber through the cavity of the middle part of the spool, the end cavities of the spool are alternately connected via the control channels with the rear and front chambers and the exhaust chamber, and the drummer made three-step. The diameter of the rear steps which pain5. above the diameter of its average stage, but less than the diameter of the front stage. Sources of information taken into account in the examination 1, USSR Copyright Certificate 0 No. 246442, cl. B 25 D 9/20, 05/27/68. 2. USSR Author's Certificate No. 501863, cl. B 25 D 17/24, 1976 (prototype).