SU1132019A1 - Double-telescopic hydraulic prop - Google Patents

Abstract

HYDRAULIC STAND DOUBLE 1 TELESCOPICITY, including a cylinder in which the first and second stages are placed, the piston cavities of which are connected through an auxiliary valve in the rod to the second stage with a valve lock and a bumper cavity of the main safety valve connected in series with the auxiliary valve. and the subvalve cavity of the hydraulic lock is connected to the atmosphere which, in order to increase the reliability of and simplify its control, it is equipped with a check valve with a pusher, the valve over the valve is communicated with the subvalvular cavity of the auxiliary safety valve, and the valve is connected to the atmosphere with a junction (the regulator is installed with the ability to interact with the locking element non-return valve during the first stage operation.

Description

WITH

The invention relates to coal mining, namely to the means of securing the cleaning faces of coal mines. A double telescopic hydraulic strut is known, in which constant resistance is achieved by automatically changing the pressure of the fluid in the working chamber by means of successively installed in the safety strut: valves. The rack includes a cylinder with successively arranged in not two rods, two working chambers of the first and second stages, equipped with main and auxiliary valves, while constant resistance is achieved by pre-adjusting the auxiliary safety valve operating at the second stage stem compliance in series with the main safety valve 1j. However, this device does not provide reliable operation of the rack. Closest to the present invention is a double telescopic hydraulic strut, comprising a cylinder in which the first and second stages are housed, the piston cavities of which; connected through a channel in the second stage of the second stage with an over-valve cavity of the hydraulic lock and subvalvular cavity of the main safety valve connected in series with the auxiliary safety valve, the valve valve and the sub valve valve of the hydraulic lock are connected to the atmosphere. The total flow pressure of these valves determines the value of the resistance of the second-stage stem when it is compliant under load. Pliability of the first-stage stem occurs after the full lowering of the second-stage stem when it is. The collar count coincides with the radial hole in the first-stage stem and, therefore, the working chamber of the rack. In this case, the liquid, the auxiliary safety valve, flows into the subvalvular cavity of the main safety valve, when the pressure of the working chamber decreases, the j value inversely proportional to the increase in the working area of the rods, which accept the hydraulic force from the working chamber 2j. A disadvantage of the known stand is the complexity of the additional hydraulic inside the rack connecting the valve valve to the main safety valve with the working chamber, reducing the reliability of the stand, since the process of joining the radial window on the first stage stem with end groove on the second stage stem proceeds with the inevitable intensive destruction Sealing knots, second stage. The purpose of the invention is to increase the reliability of the rack by simplifying its design. The goal is achieved -) By the hydraulic stand of double telescopicity, including a cylinder in which the first and second stages are placed, the piston cavities of which are connected through a channel in the second stage with the valve valve and the subvalvate cavity of the main safety valve connected in series with the auxiliary valve a safety valve, the supravalve cavity of which and the subvalve cavity of the hydraulic lock are connected to the atmosphere, equipped with a check valve with The valve, whose valve chamber communicates with the sub-valve cavity of the auxiliary safety valve, and the valve valve with the atmosphere, the pusher is installed with the ability to interact with the locking element of the check valve when the first stage is put into operation. The drawing shows the hydraulic strut in the extended position, a longitudinal section. The hydraulic strut consists of cylinder 1, inside which are installed the shafts 2 and 3 of the first and second stages with a head 4. On the upper end of the rod 3, and a hydraulic unit 5 containing a back-discharge valve 6 with a piston 7 and a handle 8, in series with the main 9 and auxiliary 10 safety valves and a check valve 11 provided for its forced opening, for example, with a pusher 12. The subvalvular cavity 13 of the main safety valve 9 is connected by a channel 14 to the working chamber 15 of the rack, and the subvalvate cavity 16 of the auxiliary relief valve 10 is connected by a channel 17 to the subvalvate cavity 18 of the check valve 11, the over valve valve of which is connected to the atmosphere through the channel 19 20. Through the same channel, the liquid drains when the auxiliary safety valve 10 is activated and during the forced opening back - unloading valve 6 pusher. Spreading and pre-racking is performed by supplying fluid (from an external power source) to channel 20, which is hydraulically connected to the common cavity for the piston and the back-unloading valve 6. Under the pressure of the liquid, the unloading valve 6 opens. overcoming the resistance of the spring and the fluid through the channel 14 enters the working chamber 15. At the same time, the main 9 and auxiliary tO safety valves remain closed by the force of their springs, and the shut-off valves (balls) are also two-way gi hydraulic pressure from the power source (i.e., hydraulically balanced due to the presence of channel 19 and check valve M). After pressing the head 4 to the top of the reservoir, the flow of fluid into the working chamber 15 is stopped and the return-discharge valve 6 is closed by force of its spring, completely sealing the working chamber 15 n, thereby providing the possibility of connecting the channel 2b with the atmosphere. As the side rocks approach each other, the pressure of the working fluid in the rack increases to the total throughput pressure of the main 9. and auxiliary 10 safety valves. These valves sequentially operate and the stem 3 is lowered, the resistance value of which is determined by the total pressure of these valves and the working area of the stem 3. After the safety valves 9 and 10 have triggered, the working fluid enters the drain 20. After the rod 3 is fully lowered pusher 12 interacts with the upper end of stem 2, moves up and opens the return valve. pan 11. The pressure of the working fluid in the working chamber 15 is automatically reduced to the value of the throughput pressure of the main relief valve 9, since when it is triggered, the liquid, the auxiliary valve 10, flows into the channel 17 and through the open non-return valve 11 to drain through the channel 19 and 20. The resistance of the rack in this case is determined by the value of the throughput pressure of the main safety valve 9 and the total working area of the rods 2 and .3. Appropriate safety adjustment of the safety valves achieves an equal resistance of the rack, both when the first-stage stem 2 is pliable and that of the second-stage Rod 3. By connecting the sub-valve cavity of the auxiliary safety valve with a channel made in the hydraulic block with the valve valve sub-valve cavity installed with the possibility of connecting its valve valve cavity with the atmosphere, an auxiliary safety valve is balanced by atmospheric pressure with the reverse valve open, which allows automatic change of the mode fluid pressure in the working chamber of the rack by simple structural means with a high degree of reliability their work, providing the necessary operational reliability of the rack.

1132019

6,055

TO

17

2B

Claims (1)

HYDRAULIC RACK OF DOUBLE TELESCOPICITY, including a cylinder in which the rods of the first and second stages are located, the piston cavities of which are connected through the auxiliary channel in the second stage rod to the valve with a hydraulic lock and the valve of the main safety valve connected in series with the auxiliary safety valve, whose valve the under-valve cavity of the hydraulic lock is connected to the atmosphere ^ characterized in that, in order to increase the reliability of the rack and the remission of its management, it is provided with a check valve tappet supravalvular cavity which communicates with the cavity subvalvular auxiliary safety valve and subvalvular - with the atmosphere, wherein the pusher is mounted for cooperation with a locking element of the check valve when the operation in the first stage. 1132019 2 The disadvantage of the well-known rack