SU968654A1 - Stand for investigating pneumatic percussive machines - Google Patents

Description

The invention relates to test equipment, in particular, to stands for the study of parameters of pneumatic percussion instruments and drilling machines with reciprocating movement of the tool.

A stand for studying pneumatic percussion machines is known, comprising a frame, a cylinder, a hammer, and measuring equipment 1.

. The disadvantage of this stand is that it allows the control of the basic parameters of ready-made machines with specific structural dimensions. When creating pneumatic machines, especially with throttle air distribution, it is very important to correctly set the ratio of the volumes of the working and idling chambers. In this stand, changing the volume of the chambers is possible only by replacing or substantially upgrading its working cylinder.

Closest to the invention of the technical entity is a test bench for pneumatic percussion machines, comprising a cylindrical body, a hammer located therein, dividing the body cavity into chambers of the working and idling strokes, a device for compressed air inlet, and p I5 tool 2.

The disadvantage of the known article is that its construction does not allow

10 nyu volumes keiMep working, and idle without disassembly and modernization of the stand.

The aim of the invention is to increase the efficiency of research for

15 account of adjusting the volumes of working and idle chambers ..

This goal is achieved by the fact that in a test bench for pneumatic impact percussion machines, comprising a cylindrical body housed therein, dividing the body cavity into working chambers; what and idling, the device for the inlet of compressed air and the worker

25 tool, the case from the end side is equipped with sleeves mounted for movement along its axis, and the device for inlet of compressed air is made in the form of Two

thirty

fittings located on the respective ends of the glasses.

The drawing shows a test bench for the investigation of pneumatic impact machines.

The stand contains a cylindrical case 1, inside of which there is a drummer 2, which divides the cavity of case 1 into chambers of working 3 and single 4 strokes. Disks 5 and 6 are fixed at the ends of the housing 1 and connected with the possibility of moving along the axis of the housing 7 and 8 placed from the ends of the corpus 1. In the glasses 7 and 8 from their ends there are nozzles 9 10 for compressed air inlet, having calibrated channels 11 and 12. The glass 8 has a central hole 13 for accommodating the shank of the working tool 14. The housing 1 is fixed on the frame 15. A channel 16 is made to release the exhaust air in the housing 1.

The stand works as follows.

Compressed air supplied from the main through calibrated channels

11 and 12 fittings 9 and 10 simultaneously enters the working chamber 3

and idle 4 strokes. Since chamber 3 is connected to the atmosphere through outlet 16, the pressure in it remains close to atmospheric. In chamber 4, as compressed air enters, the pressure increases. Due to the pressure difference in chambers 3 and 4, the impactor begins to move to the side of glass 7. After the hammer 2 of the discharge channel 16 is blocked, the air in chamber 3 is compressed. Since the volume of chamber 3 is greater than the volume of chamber 4, the pressure in chamber 3 does not grow as fast as in chamber 4, and drummer 2 continues to move toward glass 7 due to the pressure difference. After the drummer 2 opens the outlet channel 16 from the chamber 4 side, the pressure in it drops almost to atmospheric, and the movement of the drummer 2 continues only due to inertial forces.

When the inertial forces disappear, the impactor 2 under the action of pressure from the chamber side 3 begins to move toward the tool 14, making a working stroke. . After the discharge channel 16 is blocked, the hammer 2 in chamber 4 begins to compress the incoming through the calibrated channel.

12air. Moving the side of the shank of the tool 14, the drummer 2 opens the exhaust channel 16 with

the sides of chamber 3, as a result of which the pressure in it drops almost to atmospheric. Overcoming the resistance of the air compressed in chamber 4, the striker 2 strikes the tool shank 14. Then the process repeats.

In the process of investigating a pneumatic machine, moving the cups 7 and 8 along the axis of the housing 1, 0 smoothly and independently change the volumes of the chambers of the working 3 and idle 4 strokes, and the location of the nipples 9 and 10 for air inlet at the ends of the cups reduces the volume of 5 chambers , created with the help of glasses, down to zero, without interfering with the air intake from the network. Using the measuring equipment, it is possible to determine the volumes of the chambers at which the best combinations of the eergetic parameters (impact energy, impact frequency, air flow) of the pneumatic machine are obtained.

Creating a stand in which the slave cylinder is equipped with glasses installed with the ability to move along the axis of the cylinder can significantly (5-10 times) reduce the time for completion and thereby accelerate the creation of reliable, high-performance pneumatic impact machines.

Claims (2)

1. Manual pneumatic hammers. M., Mechanical Engineering, 1967. 2. USSR author's certificate No. 218787, cl. E 21 C 3/24, 1967 (prototype). Network