FI79893C - Device which enables the input of a hydraulic double-acting lifting device on the basis of single or double-acting control of the direction change - Google Patents

Description

1 79393

The present invention relates to an apparatus for enabling the automatic reversal of the supply of a hydraulic double-acting hoist on the basis of a single-acting or double-acting control.

When, in a double-acting hoist, a certain pressure-10 fluid is released into the second chamber, the fluid in the second chamber is pushed into the tank. When the internal or external response stops the movement of the hoist, the discharge flow ceases completely.

The device according to the invention is characterized in that the information which causes a reversal is taken from the emptying chamber of the hoisting device by means of a detector device which detects both the status of the hoisting chamber's emptying chamber and the absence of a supply and reverses when the supply is zero.

20 As long as said chamber becomes a certain amount of feed, no reversal control takes place. At the end of the feed, the reversal is controlled and stored in memory until the end of the cycle.

When a stable position is reached, the lifting device always runs an automatic travel and return cycle at once. According to the coupling direction of the lifting device to the device according to the invention, the lifting device has a stable position when the piston rod is outside or inside when the automatic reversal takes place after the arm has stopped, either in the internal or external response.

The feed detection device is controlled by a timing device that either gives a command or does not give a command to the control of the reversing distributor.

Other features and advantages of the present invention will become apparent from the following description, taken with reference to the accompanying drawings, in which Figure 1 is a diagram of a device according to the invention in sleep mode and Figures 2-4 are diagrams showing the same device in other stages.

The device according to the invention generally comprises a detector device 11,12,12A, 15 which detects the state of the supply of the discharge chamber of the lifting device and the failure of the supply, a timing device 5,6,9,10 which slows down the detection of this supply, and a controlled a non-return valve 1,2,3,4,22 which locks said double-acting lifting device when its piston rod is open.

Figure 1 shows the device in the rest position, i.e. its openings P (pressure) and V (drain) can be closed or open with respect to the container by a distributor (not shown) with external control.

The lifting device connected to the openings A and B is locked by a controlled check valve 1,2,3,4,22 with the piston out. The device's dual-function automatic supply takes place on 20 channels A1 and B1.

In general, the amount of feed available at A1 and B1 is at the stage when the pressurized liquid leaves the channel B1 when A1 is in the emptying stage and in the second, i.e. reversing stage, when the liquid leaves the channel A1 when the channel B1 is in the emptying stage.

When the pressurized liquid is introduced from the opening P, the opening V being in the emptying stage (Fig. 1), the liquid acts on the timing piston 5,6,9,10, thereby delimiting two chambers, a chamber 10 communicating with the channel B1 and a chamber 9, 30 communicating with the channel A1 , via a calibrated nozzle 8. In its normal rest position, the piston 5 has returned under the action of the spring 6 and closes the channel 7. The time required to empty the chamber 9 at the calibrated nozzle 8 determines the timing which makes it possible to assume that the hoist movement has begun 3 79893 before the discharge feed state is detected. 12 and 12A can be closed before the channel 7 is opened.

Figure 2 shows the lifting device as it moves in the return direction of the piston rod. The liquid coming from P fills the annular part of the lifting device 5 and activates the control device 1, which opens the flap 3 of the control check valve 1,2,3,4,22. The liquid in the bottom part of the lifting device exits to the space 13 where it is forced to move to the channel 14, move the slider 11 of the feed detection device 10 11,12,12A, 15, which causes the channels 12 and 12A to close. The time required to start the piston, i.e. from the moment when the liquid is introduced until the channels 12 and 12A are closed, is shorter than the movement of the timing piston 5 until the channel 15 7 opens.

When the displacement of the lifting device is terminated by an internal or external response (Fig. 3), the emptying supply ends in state 13, and the slide 11 returns to its initial position by means of a spring 15, which opens the channels 12 and 12A and 20. the drain flap 16 and in the second stage the reversing slide 17.

The liquid fed into the opening P (Fig. 4) flows through the space 18 and feeds the closed part of the lifting device through the valves 19 and 25. The non-return valve 20 opens and allows the liquid to enter the chamber 21. The non-return valve 27 prevents the liquid entering the chamber 21 from escaping through the channels 12, 12A and 7 (the channel 7 does not close immediately).

This arrangement associated with the valve 20 and the valve 27 causes the position of the slider 17 to be stored in the memory, said position being maintained by the valve control device 16 as long as pressure is applied in the opening P. By means of the calibrated nozzle 8, the liquid pushes the timing piston 5 back to its initial position. The chamber-shaped chamber 35 of the hoisting device, the chamber 10 and the second chamber 22 of the controlled check valve 4 79393 are emptied through a space 23 which communicates with the opening V.

When the compression in the opening P has ceased, the valve 20 closes again and the liquid in the chamber 21 exits through the calibrated nozzle 24, thus allowing the volume to change. The control device 16 can return to its initial position by means of a spring 25 and the slider 17 by means of a spring 26.

It is clear that the present invention has been described and illustrated by means of figures only as a preferred example, and that corresponding modifications may be made to its parts without departing from the scope of the invention.

As a result, from the channels A1 and B1, 15 different branching possibilities of the hoist and the controlled check valve can be provided without changing the operation of the hoist, i.e. - lock the hoist ring-shaped part and leave the hoist closed part free, 20 - lock both parts, and - change the cycle direction by changing the hoist direction of other parts.

Claims (3)

Device which enables automatic cyclical change of the direction of a double-acting lifting device cyclic, characterized in that the data which corresponds to the change of direction are taken from the emptying chamber of the lifting device by means of a detector (11,12,12A, 15), which detects both the feeding state of the lifting chambers emptying chamber and the lack of feeding and will change the direction when the feed is noil. Device according to claim 1, characterized in that a certain time control device (5,6,9,10) delays the detection of the zero supply of the emptying chamber, so that the lifting device can start at its normal resting state. Device according to Claim 1 or 2, characterized in that it comprises a direction-changing slide (17) which is poured into a position offset by the discharge valve (16), which is adjustable by supplying pressure fluid by the detector device (11). , 12, 12A, 15), that a check valve (27) is located between the detector device and the control chamber (21) of the discharge valve (16), and that the chamber (21) is connected to a pressure opening (P) by another check valve (20). after the change of direction of the air device, said offset position being recorded in memory where the pressure opening (P) exhibits pressure.