SU124091A1 - The control device telescopic jacks double action - Google Patents

Description

The known dual-action telescopic jacks control devices, which provide a predetermined order of motion of the cylinder jacks that make up the components, by creating appropriate pressures in the forward pressure chamber and the backpressure chambers, do not allow remote control.

The described device differs from those known in that, in order to provide remote control with partial automation, it is implemented with a reversible three-position electromagnetic or electro-hydraulic slide valve and an automatic butterfly valve included in the hydraulic control circuit. The automatic throttle valve is made up of a spring-loaded brush, controlled by a return ball valve inserted into the main chamber of the direct pressure of the hydraulic jacks, and mounted in a reservoir containing a spring of the rod, a non-return ball valve included in the main back pressure of the hydraulic jacks. The spring of the rod is adjusted to ensure that the pressure in the direct pressure chambers of the hydraulic jacks is necessary to hold their inner cylinders in the fully extended position during the removal of the outer cylinders, and the check valve included in the backpressure chamber line is adjusted to create pressure in the backpressure chambers, required for the removal of the inner cylinders of the hydraulic jacks, which is set greater than the pressure required to open the non-return ball valve th line in the forward pressure chambers. To bring the hydraulic system to the initial position, in case of failure of a pumping unit or a reversible spool valve, the automatic throttle valve is made with a handle for

№ 124091

forced opening of a check ball valve included in the line of the direct pressure chambers.

The drawing shows a schematic diagram of the described device-remote, control of double action telescopic jacks;

The device includes an oil pump unit 1, a pump unit 2, a test pressure gauge 3, a drain valve for a pump unit 4, a reversible three-position solenoid or electrohydraulic spool valve 5, an automatic throttle valve 6 and a drain valve 7 for a backpressure chamber 8 of the working element 9.

The working body is one or several parallel working telescopic hydraulic jacks of double action.

The automatic throttle valve 6 is made up of a spring 11 spring-loaded shtochka 11 controlled by a back pressure ball valve 13 connected to the main pressure chamber 12 hydrojacks and mounted in a reservoir 14 containing spring 10, a back pressure ball valve 15 included in the back pressure chamber 8 hydraulic jacks.

The spring 10 is adjusted in order to provide the pressure in the direct pressure chambers 12 required to hold the inner cylinders of the hydraulic jacks in the fully extended position while retiring the outer cylinders.

The check valve 15 is configured with regard to the creation of pressure in the counter-pressure chambers 8, necessary for removing the internal cylinders of the hydraulic jacks, which is set higher than the pressure necessary for opening the check valve valve 13.

With the help of a screw with a handle 16, in the event of a failure of the pumping unit 4 or the spool valve 5, the system is emergencyly lowered by forcibly opening the check valve 13.

When the hydraulic jacks for lifting are operated, the liquid from the pump unit 4 through the distributor 5, pressing the spring of the check valve 13, enters the direct pressure chamber 12 of the hydraulic jack, producing its internal cylinders 17 in the initial period; the outer cylinder 18 is held in the fully retracted position by the pressure in the backpressure chamber 5. After the inner cylinders come out, the pressure in the chamber 12 rises, causing the pressure in the chamber 8 to rise to the pressure of the drain installed on the valve 7, and the outer cylinder starts to extend. Valves 7 and 15 provide for the stop of the hydraulic cylinder when the maximum tensile load is applied to it in the event that the supply of working fluid to the chamber 12 is stopped.

When lowering the hydraulic jacks, the working fluid flows through the distributor 5 into the chamber 8, overcoming the spring pressure of the check valve 15. Since at this moment the chamber 12 is locked by the non-return valve 13, the pressure in the chamber 8 increases. The stem 11 of the automatic throttle clan 6 with increasing pressure of the working fluid in the chamber 8 overcomes the force of the working spring 10, moves to the left and opens the check valve 13; therefore, there is a drain from the chamber 12 through the throttle opening formed by the seat of the check valve 13 and the end of the rod //. When the pressure in chamber 8 drops below the value of the setting of the automatic throttle valve 6, the spring 10 retracts the rod 11 to its initial rightmost position, and the check valve 13 closes the direct pressure chamber 12 of the hydraulic jack.

The removal of the inner cylinders J7 of the hydraulic jacks is carried out by leaking the working fluid through the throttle orifice formed by the seat of the check valve 13 and the end of the stem //.

During the removal of the inner cylinders 17, the pressure in the chamber 12 is determined by the external compressive load and the working area of the cylinders. The pressure in chamber 8 during the retraction of the inner cylinders 17 is determined by the setting of the drain valve 7, and this pressure must be greater than the pressure opening the check valve 13.

The elevation speeds of the cylinders 17 and 18 as they are raised are determined by the pump capacity and the working area of the cylinder being extended, and when the system is lowered to the initial position, the cylinder retracting speed is determined by the capacity of the throttle hole formed by the check valve seat 13 and the end of the rod 11 , and in the period of cleaning the outer cylinder also the performance of the pumping unit.

Subject invention

Claims (4)

1. A dual-action telescopic hydraulic ram control device providing a predetermined order of motion of the cylinder ram components by creating appropriate pressures in the direct pressure chambers of the hydrojacks and their backpressure chambers, characterized in that in order to provide partial automation of remote control, it is provided with into the hydraulic control circuit of a reversible three-position electromagnetic or electro-hydraulic spool valve and an throttle valve. 2. The form of the device according to claim 1, characterized in that the automatic throttle valve is composed of a spring-loaded brush operated by a return ball valve inserted into the main chamber of the direct pressure of hydraulic jacks, and a ball return valve mounted into the reservoir containing the spring of the brush valve included in the line of backpressure chambers jacks. 3. The form of the device according to paragraphs. 1 and 2, characterized in that the spring of the rod is adjusted to ensure the pressure in the direct pressure chambers of the hydraulic jacks necessary to hold their inner cylinders in a fully extended position during the retraction of the outer cylinders, and the check valve included in the backpressure chambers is configured with taking into account the creation of pressure in the chambers of the back pressure necessary for the removal of the inner cylinders of the hydraulic jacks, which is set greater than the pressure required to open the return ball ovogo valve incorporated in the line direct pressure chambers. 4. The form of the device according to paragraphs. 1-3, characterized in that, in order to bring the hydraulic system to its original position, in case of failure of the pumping unit or reversing spool valve, the automatic throttle valve is equipped with a handle for forcing the opening of the back pressure ball valve included in the main line of the forward chambers pressure. - 3 - № 124091