JPS6114362B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a hydraulic device, particularly of the low pressure type.

The hydraulic device according to the present invention includes a prime mover, and the hydraulic device is driven in a first direction (hoisting direction) that opposes an external force.
and a second direction (rewinding direction) that coincides with an external force, the hydraulic device is configured such that the working medium of the prime mover is controlled by an operating valve through a first passage and a second passage. It is. The device further comprises a discharge conduit associated with a pressure medium-controlled discharge valve, in which the discharge side of the discharge conduit is connected to the first passage, and the discharge side of the discharge conduit is connected to the discharge valve of the actuating valve. A control conduit of the discharge valve is connected to said second passage.

A hydraulic device of the above type is described in US Pat. No. 3,667,859, in which the discharge valve is used as a limit valve to limit rotation in the unwinding direction.
That is, it is used as a valve that can produce a desired rewind limit by discharging the working medium through the discharge valve while the motion of the prime mover is in a second direction (rewind direction) coinciding with the external force. There is.
Further, an abnormal pressure drop is prevented from occurring in the prime mover and the operating valves, and abnormal operation of the operating valves and the like is prevented. In this way, even at maximum loads, the hydraulic prime mover can be controlled without fear of overloading the operating circuit, and even unskilled personnel can safely operate the prime mover.

The present invention is based on the use of a valve similar to that described in U.S. Pat. It is to be used for. One of its functions is to implement effective tension control, ie, controlled pressure limiting as well as limiting impulsive pressure-increasing effects in the actuation circuit.

According to the invention, the hydraulic system comprises a first
a prime mover adapted to be driven in a direction and a second direction through a first passage and a second passage by being controlled by an operating valve and a discharge valve in combination with a discharge valve controlled by a pressure medium; The duct includes a discharge port whose feed side is connected to the first passage and whose discharge side is connected to the discharge side of the operating valve, and a control conduit for the discharge valve, the control conduit being a discharge conduit passing through a control valve such that control pressure from said second passage can be freely transmitted through said control conduit to a control force chamber of said discharge valve; The valve includes a slider which is urged distally by pressure from the first passageway against an opposing regulating force, the slider being in its open position through the control conduit. forming a free connection between the first passageway and the second passageway;
This applies a pressure intermediate between the pressures in the first and second passages to said control force chamber, which chamber is connected to the branch connecting said control valve to said feed side of said conduit. When the pressure in the pipe reaches a level equal to or higher than the adjustable counterforce, the discharge valve is opened to form a passage from the first passage to the discharge side of the operating valve. Accordingly, the pressure in the first passage is restricted.

It has thus now been discovered that, using relatively simple additional accessories, it is possible to make the discharge valve perform additional functions other than the rewind limiting function. In this case, the discharge valve can have a wide range of use without significant complexity.
Therefore, by carrying out an adjustment of the counterforce in the control valve, it is possible to safely and reliably adjust the desired pressure limit in the working circuit of the prime mover as required, independent of the rewind control function. It will be.
Therefore, under different operating conditions, the same discharge valve can be used to perform different discharge functions;
One feature does not complicate or interfere with another.

The counterforce in the discharge valve can consist of the force of a spring or the pressure of a pressure medium with variable pressure and the force of a spring. The force of the spring can be controlled by an adjustment screw or similar control device.

By using an adjustment screw or similar adjustment device, adjustment of the counterforce can be carried out to directly adjust the pressure control function.

In a remotely controlled construction, in addition to the spring pressure adjustment, an additional remote adjustment by means of a pressure medium can be carried out by relatively simple means. For example, in the case of spring pressure adjustment the counterforce can be adjusted to a certain minimum pressure, for example to a pressure of 7 Kg/cm ² , whereas in the case of remote regulation the counterforce can be adjusted to an even higher value with a pressure component medium. It can be adjusted to the level.

Thus, using a remote control valve in the form of a pressure reducing valve, it is possible to adjust the counterforce as needed to the desired level. The pressure reducing valve receives its feed pressure from the pressure side of the prime mover, the return side of the pressure reducing valve is connected to the return side of the operating valve, and the operating conduit controlled by the slider of the pressure reducing valve is connected to the counterforce of the control valve. communicate.

Hereinafter, the present invention will be explained in detail with reference to embodiments shown in the drawings.

Referring to FIGS. 1-6, a constant volume hydraulic system is illustrated with an irreversible pump 10, from which a fluid supply conduit 11 extends to an inlet 12 of an operating valve 13. From the outlet 14 of the operating valve 13,
A return main pipe 15 is connected to the suction side of the pump 10. A circulation line 16 extends between the supply line 11 and the return main line 15 and is closed with a safety valve 17 . 17a indicates a check valve.

The prime mover 18 has three working chambers particularly suitable for operating a winding machine, and has holes 19, 20, 21 that form passages for supplying pressure medium to the prime mover when the prime mover is operated in the direction of lifting a load. and a hole 23 which forms a discharge path from the prime mover when the prime mover is operated in the lifting direction. During operation of the prime mover in the direction of lowering or lifting the load, the bore 22 forms a feed path for the prime mover, whereas the holes 19, 20, 21 form a discharge passage from the prime mover. The operation of the prime mover in one direction or the other, adjustment of the driving speed, adjustment of the stop position of the prime mover, etc., are performed using the slider 2 of the operating valve 13.
3. That is, when the slider 23 of the operating valve 13 is moved downward from the neutral position shown in FIG. Driving in the lifting direction is performed, and when the slider 23 is moved upward, the pressure medium discharged from the pump is supplied to the hole 22, and the holes 19, 20, 21 are connected to the return main pipe 15, so that the reverse rotation of the prime mover is prevented. (Norwegian Patent No.
(See No. 86819, Special Publication No. 50-5772).

An operating valve 1 is located between the operating valve 13 and the prime mover 18.
3 each control port and each hole 19, 2 of the prime mover 18
An intermediate member 24 for connecting 0, 21, and 22 is inserted, and this intermediate member has holes 19 and 2.
0 open connections 24a are provided. Further, the holes 20 and 21 are short-circuited by a connecting pipe 25. Therefore, the holes 19, 20, 21 are in direct communication with each other. A connection is made between the bore 19 and the outlet 29 of the actuating valve 13 by a discharge conduit 26 and 27 with a corresponding discharge valve 28 . One end of conduit 26 is connected to hole 19 via intermediate member 24, and one end of conduit 27 is connected to the return side of the system. The opposite ends of conduits 26 and 27 are connected to respective openings 30 and 31 of valve 28. In the position shown in FIG.
1 are separated from each other by a flange 32 of a slider 33. One end of the slider with a corresponding flange 34 is accommodated in a control pressure chamber 35 , and the other end of the slider with a corresponding flange 36 is accommodated in a backpressure chamber 37 . The control pressure chamber 35 is connected to the bore 22 by a control conduit 38, whereas the back pressure chamber 37 is connected to the conduit 27 via a branch pipe 39.
It is connected to the. A compression spring 40 is inserted between the slider 33 and the bottom surface of the back pressure chamber 37. Further, a control valve 41 is interposed in the control conduit 38 .

The control valve 41 has a pressure control chamber 43 at one end of a control slide 42 and a back pressure chamber 45 at the opposite end of the control slide carrying a corresponding flange 44 . The pressure control chamber 43 is connected via a branch pipe 46 to the conduit 26 forming the feed channel of the discharge conduit and has the same pressure conditions as each bore 19-21 of the prime mover. The back pressure chamber 45 is the back pressure chamber bypass path 4
7 with the control conduit 38 and also with the back pressure chamber 4
5, a compression spring 49 is arranged intermediate the flange 44 and the adjustment screw 48 at the bottom of the chamber.

The force acting on the slider 42 in the backpressure chamber consists of the force of the spring 49. The force of spring 49 can be adjusted by adjusting adjustment screw 48.

In the position illustrated in FIG.
is in a rest position and its slider 23 is arranged such that the inlet 12 from the supply conduit 11 communicates with the outlet 14 of the operating valve. Holes 19-21
are flanges 23a, 23b, 23c, respectively.
23d and 23e, which securely hold the motor in the stopped position. Pressure medium circulates from the pump 10 in a passage through an operating valve 13 external to the prime mover 18 .

The slider 23 is in the load lifting position, that is, in the first
When moved downward in the figure, the holes 22 feed into the holes 19, 20, 21 of the prime mover and the prime mover is driven in the direction of lifting the load. At this time, the discharge valve 28 and the control valve 41 are in the closed position as shown in FIG. Communication has been severed.

When the slider 23 is moved toward the lowered or unwinded load position, the bore 22 is in open communication with the inlet 12 and receives pressure medium from the supply conduit 11 without restriction. As a result, the prime mover 18 is driven in the rewinding direction. That is, it is driven in a direction consistent with an external force acting on the prime mover (for example, the weight of a cargo winch load). During this time, the prime mover 18 is driven as a pump by an external force. If the external forces are small, the prime mover is driven in addition to the external forces by the force generated by the pressure medium in the bore 22. In this way, the unwinding speed can be increased by the force of the pressure medium in the holes 22. If the external force is large, the unwinding speed is determined by this external force, and the problem lies in reducing the unwinding speed. The unwinding speed is
is determined by how much working medium can be introduced into the The pressure in the bore 22 can be controlled by the amount of pressure medium that is passed through the lowermost flange 23f of the slider 23 to the outlet 29. The passage of the flange 23f is narrowed or closed by the flange 23f. In the rewind position of the slider, this pressure is equal to the pressure that drives the prime mover in the rewind direction, i.e. the discharge valve 2
The opening pressure is adjusted to 8. The pressure can be at its maximum when there is no load acting in a direction consistent with the unwinding movement. The operation valve 13 has a flange 23
Because of the occlusion through f, it has to be moved from the starting position with a high rather than a low unwinding pressure.

When rewinding is to be carried out, the starting position of the slider 23 is the stop position (FIG. 1). At that time, the hole 22 is unpressurized and the discharge valve 28 is closed. When the flange 23 of the slider 23 is moved toward the position shown in
f squeezes the passage between hole 22 and outlet 29.
In that case, pressure is created in the bore 22 and at the same time the pressure in the control conduit 38 increases. When the pressure in the control conduit 38 exceeds the force (spring force) acting on the slider 33 from the backpressure chamber 37 (via the spring 40), the discharge valve 28 is opened and from the hole 19, the conduit 2
6 and 27 to form a discharge passage that reaches the outlet 29. If an external force (load on the cargo winch) attempts to pull the prime mover in the unwinding direction at a speed greater than the amount of pressure medium introduced due to the restriction of flange 23f, the pressure in hole 22 will decrease and control conduit 38 There will be a corresponding pressure drop within. Then, until the difference in the hole 22 rises again,
The exhaust valve 28 is completely or partially closed.

In the embodiment of FIGS. 1-3, while the rewind limiting function is maintained, the exhaust hole and the exhaust valve are utilized for other operating functions apart from the rewind limiting speed. A branch pipe 46 issuing from the conduit 26 controls the control valve 41, so that the control valve 41, together with the discharge valve 28, can be used as a tension-limiting-pressure-limiting structure. Thus, for example, during fluctuations in the tension of the wire of a winch (mooring winches, towing winches, trawl winches and the like) or during a sudden transition from a lifting position to a rest position (cargo winches), holes 19-21 are When the pressure in the back pressure chamber 45 increases, the connection between the branch pipe 46 and the control pipe 38 through the control chamber 43 is opened, as shown in FIG. , so that the drain valve opens and drains the excess pressure medium from the conduit 26 via the drain valve 28 into the conduit 27 and further to the outlet 29. Therefore, by adjusting the force of the compression spring 49 on the slider 42 via the adjusting screw 48, the pressure in the holes 19-21 can be adjusted to the maximum limit pressure. As soon as this maximum limit pressure is exceeded, the pressure is increased via the discharge valve 28 until the pressure in the holes 19-21 is limited to the desired pressure, i.e. to the force determined by the adjusting screw 48. Evacuation takes place. In this way, the winch can be adjusted to the desired tension limit (tension limit) and also prevent undesired pressure build-up due to braking, for example during operation in the unwinding direction, as well as undesirable pressure build-up remaining in the holes 19-21. Pressure build-up can be vented. As a result, for example for a mooring winch, trawl winch, tug winch or the like, the wire can be paid out or wound up depending on whether the external force increases or decreases.

4 to 6 show another embodiment of a hydraulic device, having a structure and mode of operation corresponding to that described with respect to FIGS. 1 to 3, but with a back pressure chamber. The only difference is that it is equipped with hydraulic pressure, and this pressure can be controlled remotely. In this way, further adjustment possibilities arise for the tension-limiting or pressure-limiting structure described above. In this regard, the back pressure chamber 45 is connected to an actuation conduit 50 leading from the pressure reducing valve 51. The pressure reducing valve 51 receives its feed pressure from the branch pipe 46 of the control valve 41 via the feed pressure conduit 52. That is, it receives a pressure corresponding to the pressure in the holes 19-21. The pressure reducing valve 51 also includes a discharge pipe 53 connected to the outlet 29 via the conduit 27 . Further, the pressure reducing valve 51 has a slider 54 having three flanges 55, 56, 57 and forming intermediate chambers 58, 59. In the position shown, the flange 56 closes the opening to the working conduit 50, whereas the corresponding intermediate chambers 58 and 59 communicate with the feed pressure conduit 52 and the discharge conduit 53, respectively, so that the pressure in this slider is Two opposing compression springs 6
0,61 and the pressure in the corresponding chambers 62,63. One compression spring 60 is arranged in a chamber 62 which is connected to the actuation conduit 50 via a branch 64, while the other compression spring 60
1 is arranged in a chamber 63, and this chamber 63 has a branch pipe 6.
5 to a discharge pipe 53. Compression spring 60 has a constant compression force, while the force of compression spring 61 is adjustable by wheel 66. By increasing the force on spring 61, slider 54 can be pushed downwards in the accompanying figures;
The pressure in actuation conduit 50 is increased until the pressure in chamber 62 and the force from spring 60 balances the force of spring 61. By correspondingly reducing the force from the spring 61, the slider 54 is forced upwardly, thereby reducing the pressure in the actuating conduit 50 to a corresponding extent, and equalizing the force on both ends of the slider. Drainage takes place from the working conduit 50 via the chamber 59 to the discharge pipe 53 until .

During use of this device, the slider 42 of the control valve 41
5 to the position shown in FIG. 6, an increase in pressure occurs in the working conduit 50, so that the slider 54 of the pressure reducing valve 51 is moved upwards in the figure, causing the intermediate chamber 59 to move upwardly. A corresponding pressure discharge occurs via the discharge pipe 53. slider 4
As soon as 2 is returned to the position shown in FIG.
A pressure drop occurs in the working conduit 50, so that the slider 54 of the pressure-reducing valve 51 is moved downwards in the figures, and the pressure is removed from the feed conduit 52 to the intermediate chamber 58 until a balance of forces is obtained at both ends of the slider 54.
A corresponding pressure increase is obtained through .

A particular advantage of the remote control system of the embodiment of FIGS. 4 to 6 is that this system is based on pressure transmission in the conduits 50, 52, 53 without any pressure medium flow. . Therefore, even with the use of relatively viscous pressure oil in the hydraulic system and long pipes, precise pressure regulation is obtained in the conduits 50, 52, 53, with rapid and complete control. It will be done. In FIG. 6, the slider 4 of the control valve 41
2 is moved from the position shown in FIGS. 4 and 5 to the position of FIG. 6 during the short time interval in which the pressure transmission in conduits 50 and 52 is indicated by arrows. In this case, from the back pressure chamber 45, the conduit 50 and the valve 5
1 and the discharge side 2 of the actuating valve 13 via the conduit 53
Only a certain minimum amount of movement to 9 is at issue. As soon as the movement of slider 42 to the position shown in FIG.
4 will be lowered to the starting position of FIGS. 4 and 5. During the time interval (not shown) in which the slider 42 of the valve 41 is moved back to the position shown in FIGS. 4 and 5, the pressure reducing valve 51 (slider 54 is shown in FIG. A refilling of the back pressure chamber 45 is carried out by the flowing pressure medium through the conduit 50 (which is pushed downwards from the position) and as soon as this refilling is carried out, the slider 54 moves as shown in FIG. It is returned to the starting position shown in FIG.

[Brief explanation of the drawing]

FIG. 1 is a partial cross-sectional view of a hydraulic system in accordance with the present invention, with the control valve and discharge valve in the inoperative position and, for illustrative purposes only, the prime mover and the operating valve being shown in the off position; (However, the control valve and the discharge valve can assume positions corresponding to other positions of the prime mover and operating valve.) Figure 2 is a view similar to Figure 1, with the discharge valve in the operated position. , the control valve is in the inoperative position and the operating valve is in the relaxed position; FIG. 3 is a diagram similar to FIG. 1, but showing the discharge valve and the control valve in the activated position; ,
4 is a partial sectional view showing the hydraulic system of the present invention in a position corresponding to FIG. 1; FIG. 5 is a view similar to FIG. 4 showing the system in a position corresponding to FIG. 2; and FIG. The figure is a view similar to FIG. 4 showing the system in a position corresponding to FIG. 10...Irreversible pump, 13...Operation valve, 18
...Motor, 19,20,21...First passage, 2
2... Second passage, 26, 27... Discharge conduit, 28
...Discharge valve, 29...Discharge side, 35...Control pressure chamber, 38...Control conduit, 41...Control valve, 42...
...Slider, 45...Back pressure chamber, 46...Branch pipe, 4
8... Adjustment screw, 49... Spring, 50... Control conduit, 51... Pressure reducing valve, 52... Feed pressure pipe, 53...
...Discharge pipe, 54...Slider.

Claims (1)

[Scope of Claims] 1. In order for the working medium to drive the prime mover in a first direction and a second direction that are respectively opposite or coincident with an external force, the first passage and the second passage are controlled by the operation valve. A discharge conduit connected to a prime mover controlled by a pressure medium and a discharge valve controlled by a pressure medium, the feed side of this conduit being connected to the first passage, the discharge side of which is connected to the discharge side of the operating valve. In a hydraulic system, the control conduit 38 of the discharge valve 28 passes through a control valve 41 so that the control pressure from the second passage 22 is free to discharge the It can be communicated through a control conduit 38 to a control pressure chamber 35 of said discharge valve 28, said control valve 41 having a slider 42, which slider 42 responds to an adjustable counterforce acting on one end of the slider 42. against the first passage 1
9, 20, 21 to a released position, in which the first passages 19, 2 are connected via the control conduit 38.
0,21 and the second passage 22, and thereby applies to the control pressure chamber 35 an intermediate pressure between the pressures in the first passage and the second passage; The control pressure chamber 35 controls the first passages 19, 20 when the pressure in the branch pipe 46 connecting the control valve 41 to the feed side of the conduit 26 increases to a level above the adjustable counterforce. , 21 to the discharge side 29 of the operating valve 13, the discharge valve 28, which is normally biased in the closing direction, is opened. 2. The adjustable counterforce is an adjustable elastic force accompanied by pressure from a pressure medium of adjustable pressure, and is characterized in that the pressure limit value in the first passage can be directly adjusted. A hydraulic device according to claim 1. 3. A manually adjustable remote control pressure reducing valve 51 having a slider 54 loaded in opposite axial directions by two opposed compression springs 60, 61 is connected to the control valve 41.
an actuating conduit 50 communicating with a backpressure chamber 45 applying an adjustable counterforce to the slider 42 of the slider 42, whereby axial movement of the slider is controlled by the first passageway 19, 20, 21. pressure is applied to the working conduit 50 from the branch pipe 46 via the feed pressure pipe 52, and movement of the slider 54 in the opposite direction causes the pressure in the working conduit 50 to be applied to the discharge pipe 53 and the discharge pipe 52. 3. The hydraulic device according to claim 1, wherein the hydraulic pressure is discharged via the discharge side 27 of the conduits 26, 27 to the discharge side 29 of the operating valve 13.