JPS6081505A - Confluent circuit of hydraulic motor - Google Patents

Abstract

PURPOSE:To improve operatability, by making back pressure of a return oil from a first-speed control valve of a first motor into an identical level with that of a confluent circuit of a second motor by providing a sequence valve downstream of the first-speed control valve. CONSTITUTION:A sequence valve 9 is provided downstream of a first-speed control valve 4 of a first motor and back pressure of an identical level with that of a confluent circuit of a second motor 16 is made to occur in a return oil circuit of a first-speed side of the first motor 6. With this construction, as return oil of the first motor 6 does not flow out by putting the oil aside toward a first-speed side, a flow of the return oil is made to divide appropriately into the first-speed side and a second-speed side by the back pressure of an identical level, return oil of the second-speed side of the first motor 6 can be supplied reliably to the second motor 16 and control of only the first speed of the second motor 16 becomes possible, slackening of speed and acceleration become possible and operatability such as inching control can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a main hoisting motor for a hydraulic crane.
211 is connected to the positive motor by connecting two hydraulic pumps to each other, and is connected to a combined circuit of hydraulic motors that supplies pressurized oil in the series 111 type.

Conventionally, in hydraulic cranes, in particular, in order to increase the speed of hoisting and lowering, the hydraulic circuit is configured as a series circuit, and a method is often used in which the oil discharged from two pumps is combined. There is. in this case,
The actuator that performs the coupling t often has two motors, a main winding motor and an auxiliary winding motor, and the arrangement of the control valves is generally such that the first pump runs, the boom goes to the auxiliary winding 1st speed, and the main winding 2nd motor runs. The speed control valves are connected to the second pump through series circuits, and the lead drum, auxiliary winding 2nd speed, and 1st winding 1st speed control valves are connected to the second pump, respectively.

In this conventional hydraulic circuit, if the supplementary 1.2 dual-use control valve is switched, the 1. After the discharge oil of the second pump is combined, it is supplied to the auxiliary volume motor to drive the motor, and the JR oil from the motor is diverted and returned to the auxiliary volume '1 and 2 control valves, and then , passes through the main winding 2nd speed and 1st speed i1i control valves, and is returned to the tank.

Here, if you switch the main one-unit control valve, what happens? The return oil from the 2nd speed side of the vol. Ii is guided to the main vol. R Lee. At this time, since the bypass passage to the tank of the main winding 2 speed control valve located downstream of the auxiliary winding 1 speed control valve is open, the return oil does not flow to the main winding motor side. Then, the entire amount flows out to the tank via the main winding 2nd speed control valve. Therefore, when the auxiliary winding is used in the first and second speeds, the main winding motor cannot be controlled even if the first winding is operated in the first speed.

In addition, when the auxiliary winding is set to 1st and 2nd speed and used, the C1 main winding is set to 1,
If both 2nd speeds are operated, the bypass passage of the main winding 2nd speed control valve to the tank is also throttled, and the back pressure on the auxiliary winding 1st speed side upstream of it is also reduced. The return oil of the Ii volume 1st speed and J: and auxiliary winding 2nd speed passes through the main winding 1st and 2nd speed control valve a11, is merged again and flows into the main winding motor, which controls the main winding motor.
However, in this case, the flow rate flowing into the first volume-[-ta] increases rapidly and is rapidly accelerated, resulting in very poor operability such as imbung fri control.

The present invention was made to solve these conventional problems, and even when the upstream motor circuit is used for both 1st and 2nd speeds, the downstream motor's 131 and 1
) is controlled by Kawaguchi, and provides a circuit that can improve operability such as inching control.

However, in the present invention, if the first pump is connected to the first Tanabata single-use control valve and the second motor's two-place control valve is connected in a series circuit, then the second pump is connected to the first The two-stage control valve of the motor and the single-stage control valve of the second motor are connected in a series circuit, and the pressure oil from both pumps is combined with the first and second speed control valves for each motor to create a series system. In the merging circuit of the hydraulic motor configured to supply the oil at It is characterized by the fact that a sequence valve is installed to ensure the same radius.

Hereinafter, the present invention will be explained based on one embodiment shown in the drawings.

FIG. 1 is a hydraulic circuit diagram showing a first embodiment of the present invention. In the figure, the basic circuit configuration includes a first pump running, a boom, an auxiliary winding 1st speed, and a main winding 2nd speed. control valve 2.3,
4.5 are connected in a series circuit, and each control valve 12 for running to the second pump 11, third drum, auxiliary winding 2nd speed, and main winding 1st speed.
, 13, 14°15 are connected in a series circuit.

Pilot type directional control valves are used for the registered control valves 2 to 5 and 12 and -15 as shown in the figure.

These six valves are each controlled by lever operation and are switched by pressure from a remote control valve (not shown). At this time, the auxiliary winding 1 series control valve 4 alone is switched, and by shifting to 2nd gear (operating angle is manual), the pressure derived from the auxiliary winding valve t11 is low. The Vaillower 1 pressure from the remote control valve becomes high, and both the auxiliary winding 1.2 control valves 4 and 14 are exchanged with l/J. In addition, the main winding 1st and 2nd speed control valves 15,
5 is also switched in accordance with the operating angle of the main winding lever in the same manner as in the case of the auxiliary winding.

A predetermined actuator is connected to each of the control valves 2 to 5 and 12 to 15, but in the drawing, of these seven actuators, only the auxiliary winding motor 6 and the main winding motor 1 are connected.
Only the motors 6 and 6 are shown in the figure, and the auxiliary winding motor 6 is used as a first motor to merge on the upstream side, and the main winding motor 16 is used as a second motor and are merged on the upstream side. 7 and 17 are counterbalance valves, and 8.18 is an overload Lilino valve.

In contrast to the basic circuit described above, in the present invention, J3 is installed downstream of the auxiliary winding 1st speed control valve 4, downstream of the main winding 2nd speed control valve 5, and in the middle of the return oil circuit 26 to the tank 10. A sequence valve 9 is installed.This sequence valve 9 is normally closed.
There is a variable linoleon valve (C) of
Relief setting 1 by Eroki guided by M9 circuit 40
■ is controlled so that it becomes high. The circuit 40 is pi [, l
The valve 41 is connected to the circuit 42 and the circuit 43 so as to be switchable. Pressure on the high pressure side is selected and introduced into the circuit 43 from the circuits 3/1 and 35 on both sides downstream of the counterbalance valve 17 of the main winding motor 16 by the seat valves 44. .

Circuit 42 is connected to tank 10.

On the other hand, a circuit 47, a circuit 47,
48 and the shuttle valve 49 to the pylons 1 to 48
A switching circuit 50 for the valve 41 is connected, and when the auxiliary winding double control valve 14 is switched, the pylon l-valve 4'1 is switched.

Next, the operation of the above circuit will be explained.

Now, move the auxiliary winding lever in the lowering direction to 2nd speed. When the remote control valve for auxiliary winding is turned down, high pilot pressure is applied to auxiliary winding 1,
The second speed control 311 valves 4 and 14 are guided by the pilot boat at the bottom of the drawing, and both valves 4 and 14 are switched to the bottom position of the drawing. The discharged oil is led to the circuit 21.31, joins at point Δ, and flows into the auxiliary winding -96, and at the same time, the counterbalance valve 7 is opened and the auxiliary winding motor 6 is driven in the lowering direction. At this time, the return oil from the auxiliary motor 6 is transferred to the counterbalance valve 7.
is diverted to the circuit 22.32 at point B, and the valve 4,
14, further passes through circuits 23 and 33, passes through the main winding 2nd speed J and 1st speed control circuit 1 digit i'5+15, and is returned to the tank 10.

In addition, in the above operation 1FII+, the pilot pressure for switching is led to the switching circuit 46 of the valve 14 and the pilot pressure for switching is led to the circuit 50 through the valves 1 to 19, and the valve 41 is connected to the pylon 1. The plan was renovated in 16th.

Therefore, the circuit 40 is communicated with the circuit 43, but when only this auxiliary winding is used, the main winding motor 16 is stopped and the J3
Since B force is not generated in circuits 34 and 35, circuit 4
At 0, the pressure is not rough, and the sequence valve 9 is only spring 1
It is only being pushed to a lower pressure (in the closing direction) than this.

Therefore, after passing through the main winding 2nd speed control Ti11 valve 5, the return oil on the auxiliary winding 1st speed side opens the sequence valve 9 with its pressure, and smooth operation occurs with only a slight pressure 10 corresponding to the spring pressure generated. The water flows out into the tank 10, and does not interfere with the driving of the auxiliary winding motor clock by the auxiliary winding 1.2 speed.

Next, when the main winding lever is tilted in the winding direction to 1st speed while the auxiliary winding is set to 1.2 itl, the low pilot pressure is applied from the main winding remote control valve to the main winding 1st speed control valve 15 shown below. The valve 15 is switched to the lower position in the drawing. Note that the main winding second speed control valve 2 remains held at the illustrated position.

As a result, the bypass passage of the valve 15 leading to the tank 10 is narrowed, making it difficult for oil to flow out from the valve 15 to the tank 10, and the return oil from the auxiliary volume 6i) S I etc. is transferred to the main volume 2.
It tends to flow to the speed control valve 5 side.

However, at this time, the valves 1 to 41 have already been switched to the right position in the drawing, and the tank 10 of the valve 15 has already been switched to the right position in the drawing.
At the same time, the bypass passage to the main winding motor 15 is narrowed down.
Because the supply passage to the auxiliary winding 2nd speed side is led from the circuit 33 through the valve 15 to the C circuit 35, the counterbalance valve 17 is turned on and the main winding 16 is filled with 81 people. Ru.

At this time, since a holding pressure corresponding to the zero load of the main motor 16 is applied to the upstream side of the counterbalance valve 17, the back pressure of the oil flowing into the circuit 35 rises, and the back pressure is applied to the shuttle valve 44. , circuit 43, circuit 40 via pylon 1 to valve 41
The relief set pressure of the sequence valve 9 is controlled in accordance with the back pressure generated in the supply side circuit 35 of the main winding motor 16. In this case, a back pressure similar to that on the supply side of the main winding motor 16 is generated on the upstream side of the sequence valve 9, and the return oil on the 1st speed side of the auxiliary winding and the return oil on the 2nd speed side of the auxiliary winding are A back pressure of the same degree is generated, and the returned oil is prevented from flowing toward the 1st turn 2nd speed control valve 5 side. On the one hand, the return oil on the 1st speed side of the auxiliary winding passes through the valve 4.5 while receiving the back pressure, passes through the sequence valve 9, and the entire flow is discharged into the tank 10, and on the other hand, The return oil from the second speed side of the auxiliary winding passes through valves 14 and 15, and is supplied to the one-winding motor 1G by a shuttle through a counterbalance valve 17.

In this way, even when the auxiliary winding is used in both the first and second speeds, the main winding 16 can be driven at the first speed overnight. Furthermore, in this case, of the return oil on the second speed side of the auxiliary winding, a flow rate corresponding to the spool spacing of the main winding first speed control valve 15 is supplied to the first winding motor 16, and the remaining flow is supplied to the circuit 3G. At the same time, the return oil from the main winding motor 1G does not flow to the main winding second speed control valve 5 side, and a flow corresponding to the flow on the supply side to the main winding motor 16 flows through the circuit 34. From there, it is returned to the tank via the main winding first speed control valve 15. Therefore, the first winding upper 916 can be driven smoothly at the first speed, and the flow ffi ill control and speed illumination at the first speed of the main winding can be smoothly driven.
1 is also possible, the main winding motor 16 can be accelerated at low speed, and the operability of inching control etc. can be improved.

Next, with the auxiliary winding in both 1st and 2nd gears, continue to move the main winding lever in the trough direction until it reaches 2nd gear.
'IM J> J, and the 2nd speed river control valve 15.5 corner b is switched to the lower part of the drawing, and hereafter, as with the conventional GJ, the return oil from the auxiliary volume 2nd gear J3 and 1st gear is transferred to the upper volume 1''a. and 2
It is connected to the circuit 25゜35 through the speed control valves 15 and 5, and the 0
After merging at the point, the water is supplied to the main winding motor 1G, and the main winding motor 16 is driven at second speed. Note that the return oil from the 1-turn motor 16 is shunted to the circuit 24.3/1 at the 0 point, and
It is returned to the tank 10 via the recording valves 5 and 15.

In this case, the main winding motor 16 is first accelerated at low speed in 1st speed,
The main winding motor 16 is then accelerated and driven at second speed.
The main winding motor 16 is smoothly accelerated and driven without any sudden shock occurring.

In the above operation explanation, the case where the auxiliary winding motor 6 is driven in the lowering direction and the main winding motor 16 is driven in the winding direction is explained, but the same applies to the case where the auxiliary winding Tanabata 6 is driven in the winding direction. The same applies to the case where the main winding motor 16 is driven in the lowering direction.

By the way, in the first embodiment described in -1-, a closed-type variable relief valve was used as the sequence valve 9, but an lff1 type variable relief valve may be used as shown in FIG.

Figure 2 shows the second embodiment of this shout! 5t) The basic circuit configuration is the same as that of the first embodiment.

Therefore, the first embodiment and the part 5Ii' will be explained in detail below, and the same OL as the first embodiment will be explained in detail.
The same reference numerals are used for the same items, and explanatory dimensions are added as necessary.
Ru.

't! In the second embodiment, a normally open variable relief valve is provided as a sequence valve 9' downstream of the one-volume, two-speed river control valve 5. ', as in the first embodiment? ili
The circuit 112 and the circuit 43' are switchably connected through the valve 41 and the circuit 112 and the circuit 43' are switched to 2-speed operation o; The circuits 52 and 53 are switchably connected via.

By 1 Tip 1 - Valve 5 'I is 1tiII for i volume 1 speed
I) [1 When the valve 15 is turned to the winding position, it can be switched to the right position in the drawing.
56.

Further, the circuit 52μ is connected to the upstream circuit of the counterbalance valve 17, and when the pilot valve 51 is switched to the right position in the drawing, the holding j-F of the one-turn motor 16 is guided to the circuit 43'. The circuit 53 is connected to a circuit 55 for switching the main winding 1st speed control valve 15 to the lowering position, and applies pressure to the 1i1J conversion pipe 1 when the valve 15 is switched to the lowering position. The circuit 43'1 leads.

Therefore, in the second embodiment, Supplementary volume 1, 2 consecutive use defense plea 4
．． 14 to the lower part of the drawing, the 1st. Second pump1. The oil discharged from '11 is A
The auxiliary winding oil merges at the point and flows into the auxiliary winding 6, the auxiliary winding motor 6 is driven, and the return oil is divided at 8 points, and the auxiliary winding oil flows into the joint valve 4 + 5.
．． 9' It is returned to the tank 10 through valves 14 and 15.

In this case, the pressure from the switching pilot 1 to the auxiliary winding 2-speed river control valve 14 switches the pilot 1 to the valve 41 to the right position in the drawing, and the circuit 40' is connected to the IQI 1fli 43'. Since the winding is not in use and the b-pi[1-II] is not led to any of the switching circuits 55, 56, the piroy 1 to valve 4-1 are held in the positions shown and the circuit 43' , Ij and the circuit /IO'. Therefore, the sequence valve 9' remains open, and the return oil on the auxiliary winding first speed side that has passed through the valve 5 is smoothly returned to the tank 10 via the sequence valve 9'. In particular, since the back sequence valve 9' is of a normally open type, the auxiliary winding-E-taro can be driven smoothly without the pressure loss that occurs in the first embodiment.

Next, with both auxiliary winding 1st and 2nd speeds in use, the winding lever is moved down to the 1st speed in the lowering direction, and the pylon 1 pressure from the main winding t-con valve is guided to the circuit 55. When the main winding 1st speed control valve 15 is switched to the lowering position (the position in the figure), the return oil of the auxiliary winding 2nd speed is transferred to the main winding motor 16 through the valve 14°15J3 and the circuit 34. There is an influx of people. At this time, since the main motor 16 is stopped by the counterbalance valve 17, back pressure is generated on the supply side of the main motor 916, and the back pressure reaches a pressure corresponding to the set pressure of the counterbalance valve 17. [rise.

On the other hand, during the above operation, the pylon 1-4''1 is switched to the right position in the drawing by the operation of the auxiliary winding 2nd speed. The switching pilot pressure for the control well 15 is transferred from circuit 55 to circuit 53, pi [1 to valve 51, circuit 4]
3', the pie is led to the circuit 40' through the valve 41, and the pie is forced in the direction of j (the sequence valve 9' is closed by the liter pressure).

Therefore, back pressure is generated in the return oil on the first speed side of the auxiliary winding that has passed through the valve 4.5.

In this way, when the 1st and 2nd speed auxiliary windings are used and the 1st speed of the main winding is to be changed, the pressure from the switching pylon 1 of the 1st speed of the main winding is applied to the relief set pressure of the sequence valve 9'. is controlled to generate back pressure in the return oil on the 1st speed side of the auxiliary winding, and thus,
Is the return oil from the auxiliary winding motor 6/J) et al? While preventing the flow from being biased toward the ili winding 1st speed side and the main winding 2nd speed side,
On the one hand, the return oil from the 1st speed side of the 1st winding is passed through valves 4 and 5 and returned to the tank 10 via the sequence valve 9', and on the other hand, the return oil from the 2nd speed side of the auxiliary winding is passed through valves 14 and 15. is supplied to the main winding motor 16, and the main winding motor 16 is driven in the lowering direction at first speed. In this 8iI unit, the main winding 1st speed switching pie [1st pressure] is approximately the same as the set pressure of the counterbalance jt 17, so the supply side of the 1st winding motor 16 is connected to the upstream side of the sequence valve 9'. The same level of back pressure can be generated, and the single-winding motor 16 can be smoothly accelerated to lower the winding at the first speed.

Also, with the auxiliary winding 1st and 2nd speeds in use, move the main winding lever in the winding direction to '1st speed' and turn the main winding remote control valve jp +
When the pi1 cut pressure from the auxiliary winding is led to the circuit 56 to wind the main winding 1st speed control valve 15 and switched to the F position (lower position in the figure), the return oil from the auxiliary winding 2nd speed side flows through the circuit 33 to the control valve 15. 15, circuit 35,
The counterbalance valve 17 is opened to allow the flow to flow into the main winding motor 16 at the right side of the drawing.

At this time, a tight holding pressure I is provided on the upstream side of the counterbalance valve 17 in accordance with the negative pressure, and this holding pressure is used to control the auxiliary winding motor 16 at the second speed. Excessive back pressure is created in the return oil on the side.

On the other hand, when winding with this main winding 1st speed, the switching piping pressure led to the circuit 56 is led to the circuit 54, the pilot valve 51 is switched to the right position in the drawing, and the auxiliary winding 2nd speed As the pie valve 415 is switched to the right position in the figure by the operation, the holding force of the main winding 91G is moved from the circuit 52 to the pie lobe 1 valve 51, the circuit 43',
The pylon 1 to the valve 41 are connected to the circuit 40', and the relief setting pressure of the sequence valve 9' is controlled to a value corresponding to the holding pressure of the main winding motor 16. As a result, supplementary volume 1
A back pressure corresponding to the holding pressure of the main winding motor 16 is generated in the return oil on the speed side, and thereafter, in the same manner as described above, the return oil on the auxiliary winding 1 speed side is flowed out into the C tank 10 against the back pressure. On the other hand, the return oil on the auxiliary winding 2nd speed side is supplied to the main winding motor 16 against the back pressure while controlling the flow rate by the 1,000 winding 1st speed control valve 15, and the main winding heater 16 is hoisted at the 1st speed. Acceleration can be covered.

J3, auxiliary winding 1st and 2nd speeds are used, main winding 1.2
When lowering and hoisting depending on the speed, the same amount of return oil is applied to each of the auxiliary windings on the 1st and 2nd speed sides using the 1-window 1.2 control valve, almost in the same way as in the first embodiment. While avoiding back pressure, the two return oils are recombined and supplied to the main winding motor 1G, allowing it to be driven.

In the second embodiment, instead of the valve 51 for the pylon 1, a pylob 1-valve 51' as shown in FIG. 3 may be used. When the main winding is not used, this pylon I-jt 51' is in the neutral position, opening the circuit 43' to the tank 10, and when the first winding is lowered, it is switched to the left position in the drawing to control the main winding at 1st speed. The pressure from the switching pyrower 1 for the valve 15 is guided to the circuit /13', and when the main winding is wound up, it is switched to the right position in the figure and the holding pressure of the main retarder -916 is guided to the circuit 43'.

By using this pilot valve 51, when only auxiliary winding is used, the sequence valve 9' can be reliably maintained in the open state, and pressure 10 can be reliably prevented.

In each embodiment, the sequence valve 9 or 9' is
Although it is installed downstream of the main winding 2nd speed control valve 5, it can also be installed between the main winding 2nd speed control valve 5 and the auxiliary winding 1st speed control valve 4.

In each of the above embodiments, the auxiliary motor 6 is
T: -9, they are merged on the upstream side, and the main winding motor 16 is used as the second motor, and they are merged on the downstream side.However, conversely, the main winding motor 16 is used as the first motor, and they are merged on the upstream side. It is also possible to use Sashiichi Taro as the second motor and merge the two on the downstream side. Furthermore, the first. The second motor is not limited to the main hoist and auxiliary hoist, but the first motor for extending and retracting the boom of the crane. 2nd t-
The present invention can also be applied to data.

As explained above, in the present invention, when the second motor on the downstream side is driven at the first speed C' while the first motor is used in both the first and second speeds on the upstream side, the first motor 1
A sequence valve installed downstream of the continuous control valve allows the first
[-It is possible to generate back pressure in the return oil circuit on the 1st speed side that is comparable to the back pressure in the circuit of the 2nd motor, and the return oil of the 1st motor flows out toward the 1st speed side. The return oil is appropriately divided into the 1st speed side and the 238i side with the same back pressure, and the return oil on the 2nd speed side of the 1st motor is diverted to the 2nd speed side and the 238i side.
-9, it becomes possible to control only 1)* of the second motor, allowing slow acceleration and improving operability such as inching control.

[Brief explanation of drawings]

FIG. 1 is a hydraulic circuit diagram showing the first embodiment of the present invention, FIG. 2 is a hydraulic circuit diagram not showing the second embodiment, and FIG. 3 is a hydraulic circuit diagram showing the second embodiment. FIG. 1 is a circuit diagram of main parts showing removal of valves. 1... First pump, 4... Auxiliary winding 1st speed control #t, 5
...Main winding 2nd speed control valve, 6...Auxiliary winding motor, 9,9
'...Sequence valve, 11...Second pump, 14.
... Auxiliary winding 2nd speed control valve, 15... Main winding 1st speed control valve,
41,51... pie [ltsu1-bu↑. Patent applicant Kobe Steel, Ltd.

Claims (1)

[Claims] 1. When the 1-speed control valve of the 1st motor and the 2-speed control valve of the 2nd motor are connected to the 1st pump 1 in a series circuit, the 2-speed control valve of the 1st motor is connected to the 2nd pump, The single-use control valve of the second motor is connected to the single-use control valve of the second motor through a series circuit, and the pressure oil from both pumps is combined using the 1.2-use control valve for each motor and supplied in a series manner. : In the merging circuit of the hydraulic motors configured as above, a valve J is provided downstream of the single-use control valve of the first motor so that the back pressure of the return oil circuit from this valve is equal to the back pressure of the merging circuit of the second motor. A merging circuit for a hydraulic motor, characterized in that it is provided with a sequential control valve.