JPS58113605A - Oil hydraulic circuit and control valve used for said circuit - Google Patents

Abstract

PURPOSE:To simplify the circuit constitution by transferring a pilot operation valve provided on a parallel passage to a free flow passage position or a throttle passage position by means of the difference of operating pressures of a plurality of actuators. CONSTITUTION:Neutral paths 15-18 of control valves 10-13 are connected in tandem and a pilot operation valve 33 is provided on a parallel passage 21. When a valve 13 is operated alone, a motor 22 side is at a low pressure and the valve 33 is placed at a free flow passage position 36 which is a normal state. When the valve 12 is operated to place the valve 13 at the right position, a cylinder 23 is under a higher load pressure than that of a motor 22, thus the valve 33 is not moved. Next, when the valve 13 is placed at the left position, a passage 30 is made at a tank pressure and the pressure in a pilot chamber 35 is made lower than that of a pilot chamber 34, and the valve 33 is transferred to a throttle passage position 37, thus squeezing the feed of the pressure oil into the cylinder and preventing the pressure oil from being fed restoratively during the descending stroke of the cylinder.

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a hydraulic circuit that allows one pump to operate at least two actuators, and a control pulp used in the hydraulic path.

A typical example of this hydraulic circuit is a hydraulic circuit for a power siebel.

The hydraulic circuit for the Power Seapel uses two pumps, but since each pump supplies oil separately to each one-way system, it is essentially one pump.
This is the same as operating the actuator marked *.

A swing motor and an arm cylinder are normally connected to one circuit system of the power sieve D as actuators.

In this &gl thread thread, for example, if the turning motor and arm cylinder are operated simultaneously, various problems will occur.

For example, the arm cylinder extension jIII! The load on the arm that operates under lI+ operation is as low as 4@ end when the arm is lowered to F.

Therefore, if the motor and arm cylinder are operated at 'kPJ' when the arm is lowered, the old water from the pump will flow directly to the arm cylinder with low load pressure.
There was a problem that the speed of the swing motor became slow at one end.As a solution to this problem, the hydraulic circuit and control pulp shown in 1st 2- are conventionally known.

The upstream vehicle control valve (1) controls the swing motor, and the downstream control valve (2) controls the arm cylinder.

When both upper control pulps (1) and (2) are in the neutral position, the oil in the pump (3) creates a neutral flow path (4J) and returns to 1/1tbt.

In addition, the control valve (WtW) of TfiL-, which controls the arm cylinder, is switched to the left-position by itself. It flows into the arm cylinder from the check valve (control pulp 42).

The above control pulp <211! -When switching to the right one position, m from the pump follows one parallel passage (7) and enters the control pulp sensor), and from there flows into the arm cylinder.

As a result, the oil from the control pulp (pump 1, the key that operates 2J independently) flows smoothly into the arm cylinder.

- Manryo Conte Cool Valve (If you operate 1-bar 2J at the same time, the passage will be connected to the next one.

i.e. upper fillll) control pulp (let
When the control pulp (2) on the downstream side is switched to the left - position, the pump (-1
The oil from the parallel passage (0 (14)) enters the control pulp (IJ), and from there the oil flows through the control pulp (IJ).
Motor KR people. In addition, oil enters the control valve 11m below the parallel passage (MJ) and flows into the arm cylinder from there.

Therefore, in the above case, the pressure supplied to the arm cylinder is subjected to a resistance to release, and the flow from the pump flows preferentially to the rotary motor. With the knob in the above switching state, the arm is lowered and extended on the side i! By configuring one passage, the speed of the single rotary motor does not become slow.

1 When the control pulp (2) of the lower RH is switched to the right position, oil from the pump (3) creates a parallel passage and enters the control pulp (2), and from there it flows into the arm cylinder. . In other words, in the upper right position, it constitutes a supply passage for the upward movement of the arm.

Figure 112 specifically shows the control pulp of the cocoon arrangement in Figure 1.

The disadvantage of this conventional method is that both control pulps (
It is necessary to properly use both the neutral flow path (43) that tandemly connects the two ) In the case of the load check 9P-6)', the passage configuration is 4HIk*, and the arm cylinder control pulse y + m-mo- control. Considering that the arrangement of the parbums is not necessarily constant, it becomes impossible to make the casting process as simple as possible.
The control pulp under the Tokou-ruji configuration is also slightly improved over the conventional one to reduce the amount of stress.

This will be txtined below for each of the illustrated embodiments.

FIG. 3 shows an all embodiment of the hydraulic path, in which each control pulse (2) has its corresponding actuator tW.
It is used to switch oil from Po/G trout.

When each of the control valves 4 to 4 is in the Chinese position shown in -, their neutral flow paths -4# are connected in tandem. In this state, the oil from the pump passes through the neutral flow path of each pulp (passes collapse), and returns to tank 4 from the neutral flow path of the control pulp downstream of the tank *JHIK connected tank passage 4. Each pulp is 111 LKt where the control pulp on the upstream side is on either the left or right side of the diagram.
When the FJ is changed, oil does not flow into the neutral flow path of the lower flLi4's a-le valve, and oil from the pump flows through the parallel path through the changed control pulp. Become.

In addition, in this example, control pulp (RO)
is the turning motor @twnt,, control pulp (to)
is the one that controls the arm cylinder, and below we will focus on both of them.

Now, if you switch to either control pulp (2) k shown in the diagram, the oil from the pump (2) will pass through the control pulp (6) from the parallel path (2).
Flow into the swing motor. The return oil from the rotor 1 motor (2) flows from the control valve 4 to the tank passage 4t.
- Go back to tank 4. A shuttle valve (2) is installed at the &passway to the rotary motor, and both flows INr@
- The high pressure on the supply side is made to flow to the pilot mj1g).

In addition, the Aiki arm cylinder is connected to the control pulp (2) via the seventh hood @ wealth and the piston precious ■ and Is & passage (1), but the rod -31- is connected to the &E
When the orchid is supplied, the arm rises, and the pressure is supplied to the piston at 14, and at 11 the arm descends. A bypass passageway is connected to the flow passageway leading to the rod *3m. The two pilot passageways ψ) mentioned above are connected to the pilot 11-1 on the opposite side of the pilot operating valve. However, the power of this pilot operated valve is as follows.

In other words, the above-mentioned pilot training valve control is for barrel two barrels.
So, it's the turning point for control pulp.
When placed at tlIil, the free flow S position - and i
It has two positions: the R circuit position and the circuit position. Usually, as shown in the figure, a parallel passage (2) is connected to the i-m collapse position r4.

However, control pulp (b) was harvested at a high rate,
When it is switched to either the left or right side, the rotation mode is set to a low pressure, so the pilot operation fP maintains control of the flow path position for the first time.

On the other hand, when the control valve (2) is switched to either the left or right side, and at the same time the control valve (2) is switched to the right position indicated by IJa'tlW, the oil from the pump is transferred to the turning motor (
2) and drives it, and also flows into the rod locking chamber Q# of the arm cylinder 4 to raise the 6th arm. At this time, the member pressure of the arm cylinder is higher than the load pressure of the swing motor ■, so the pilot operated valve @#
i Hold the free flow path position control shown.

Next, when the control pulp (2) is switched to the -1 left hook position, the oil from the pump (B) flows into the piston/click-1 of the arm cylinder, thereby paralyzing the arm. Since both this and Ut passage become tank pressure, the pressure in the pilot tank becomes lower than that in the pilot tank, and the pressure in the pilot tank becomes lower than that in the pilot tank.
Sakuben's position is switched to 11- by the pilot pressure of the swing motor.

When the pilot-operated valve curvature is switched to dDm position -Qt1c, resistance is applied to the oil supplied to the decorative piston.

Therefore, even if the load pressure on the arm cylinder becomes low when the scissor arm is lowered, oil will not flow into the arm cylinder (41) and slow down the swing motor.

The second embodiment of the hydraulic path shown in FIG. 4 is the same as the $111 embodiment except that the pilot operating valve NO pilot passage is implemented as the J111 embodiment.

In other words, in the pilot operation of this second theory example, one pilot chamber and the control pulp are connected to the nearby parallel: A (2) by a pilot passage, and the other pilot chamber is connected to the pilot passage. Through this, one shuttle valve is a good luck companion.

Therefore, both control pulps aaat-simultaneously operated,
In addition, when the arm cylinder (2) has a low load pressure and the arm is lowered, the supply pressure of the parallel passage (2) also becomes low.
Relatively speaking, the swing motor @0 load pressure becomes ^(). Therefore, the pilot operating valve (2) is displaced to the lR9 passage position by the Il pressure, and performs the same JrlA function as the #!1 actual example.

j16- is an Igl embodiment of the control valve, which opens its neutral flow path when the spool within the valve body is in the neutral position shown. Then, when switching the Sugeru to either the left or right, this neutral flow path
is closed, one of the actuator ports d or - communicates with the communication passage -, and the other actuator boat - or - communicates with either the tank passage (1) or ilK.

A parallel passageway is provided in the above-mentioned spool and an arch-shaped passageway, and this parallel passageway and a connecting passageway are installed.
The pilot operating valve of the present invention is provided with a pilot operating valve, and the specific configuration of the pilot operating valve is as follows.

In other words, this pilot operated valve? ) is a component that connects the load check poppet and the piston, and the load check poppet slides its cylindrical part into the housing, and connects the inside of the cylindrical part and the piston. Normally, the poppet portion is brought into contact with the seat portion by the action of the 0HIK and 9 springs. This sheet II @ is formed at the opening of the communicating passage in the parallel passage @, and therefore only oil flow from the parallel passage to the communicating passage is allowed.

The piston shaft is provided so that the cylindrical wheel weight Kll of the load check poppet can move freely, and the pilot'i71 wheel is defined by the piston shaft.

This is common to the inside of the pilot section 8, and the pressure of the communication passage 1, that is, the parallel passage, is introduced as pilot pressure through a slight gap between the housing and the outer ridge of the cylindrical part.

Further, the pilot pressure from the I* rotation motor is connected to the pilot chamber via the pilot introduction hole, the pilot passage, and the shuttle valve (2).

However, now, when the spool is moved with sand between the stones shown in Figure 6, the actuator boat and the communication passage are all over the place, and the actuator boat and the tank passage are communicated with each other. As a result, the oil from the pump sakaki passes through the parallel passage t14, pushes the load check poppet, and flows from the communication passage to the actuator boat surface, and from there to the rod 14141# of the arm cylinder. Further, since the actuator boat communicates with the tank passage, the return oil of the piston 41 (2) of the arm cylinder returns to the tank 4, and the arm cylinder moves in the direction of raising the arm.

When the arm rises this much, the load pressure on the arm cylinder 1/) becomes higher than the rotational force ratio of the swing motor (2).

The high load pressure of the arm cylinder is reduced to one pilot chamber as pilot pressure, and the load pressure of the swing motor is reduced to the other pilot chamber.

Pressure builds up between the two pilots '41eIJ-, but the piston Sakaki is worried according to the differential pressure.

That is, in the above-mentioned O-cup meeting, the piston sakaki is positioned upwardly and away from the load check poppet. If the piston Sakaki moves away from the load check poppet, the lift amount of the poppet can be greatly increased. The fact that a large lift amount can be obtained means that the opening of the poppet is large9, the pressure loss during the IIL overflow process from the parallel passage ring to the rod Yufu (2) is reduced, and the arm cylinder V4 can be operated with a large force. sell.

'& In the above case, it is clear that the arm cylinder @ is operated with a large force regardless of whether or not the swing motor (2) is operated.

Next, move the spool -' to 11 & 5 to the left.
This time, the oil in the rod @ chamber (2) of the arm cylinder 4 flows into the tank QIIKji, and the oil from the pump directly enters the piston side 31-, causing the arm to move downward.

At this time, if the swing motor @ is operated at the same time, the load pressure will be greater than the negative impulse pressure of the a-arm cylinder 4. As the piston approaches the load check poppet ring, its lift amount is reduced. If the lift amount decreases, the opening of the poppet will become smaller and the parallel passage will become smaller.
The friction resistance of the cabinet between and the communication passage increases, and oil preferentially flows into the arm cylinder (ttn), causing the speed of the rotary motor hook (t, 1!). ! There will be no need to worry.

Mayu When the above spool is moved to the left 1Ii11, and the swing motor is not being driven, K is the pylon) Since no pressure is introduced to the pylon, the poppet
In one part, it will be a stream of eyes.

6% '/1m scale control pulp Q) $2
The second control valve is a so-called puncture type control valve, and the pilot control valve is substantially the same as the first control valve.
), , -,, it is equipped with.

In other words, the load check poppet in this example has a hole in one pilot chamber for the parallel flow kI6, and the other pilot m1K has a hole in the
The pilot pressure of the rotary motor (2) hook is guided from the four pilot holes, which are equally formed with six noxing holes or spaces.

Others are l! The same applies to the second embodiment and the side part.

The third embodiment of the control valve shown in FIG.

That is, the poppet fi10 of the fourth poppet is provided with 51 parts @, and the center 11nKr and 74th Cr4f are formed. Depending on the amount of lift of the poppet 4, the orifice is opened, or the notch 0 at the protrusion (2) end is opened.

As is clear from the above description, the range set (υ
The invention described in section 64) creates at least two actuators with one O pump, and also includes control nozzles corresponding to the actuators. On the other hand, there is also a free tIL in the parallel passage in the parallel passage.
Passage and ++! In addition to providing a pilot-operated valve with a Se + The configuration is such that the position is switched to either the primary free flow path position or the passing path position wIL depending on the differential pressure between the positions.

Therefore, its circuit configuration is extremely simplified.

The invention of the yoke line (2) of Katotrapaku and,
In a control valve that is provided with a communication passage that communicates with the actuator boat according to the movement of the parallel passage spool, there is a connection from the front ml parallel passage to the I/#l-
A load check poppet that controls only the flow to the Ih road, a piston that stands opposite the back pressure acting end of this load check poppet, and a pilot chamber that is formed on both sides with this piston as a boundary. A pilot operated valve [provided in the main body of the valve and 1. One of the pilot chambers is configured to introduce pilot pressure from the parallel passage, and the other pilot chamber is configured to introduce pilot pressure of an actuator controlled by another control valve, so that the differential pressure between both pilot chambers is The moving position of the sighting vist is determined according to the piston position, and the load check poppet stroke amount is controlled based on the piston position.

Therefore, the desired purpose can be achieved by simply adding the conventional control valve Kbf.
- is a one-way diagram of the Ill implementation 11 of the A1 pressure path of this invention, FIG. The cut-away diagram showing the same <*a actual example is the WR direction diagram,
Figure 8 is also a diagram of the third embodiment.

4～-...Control valve, -...Pump, (
To) -1...neutral flow path, (2)@-...parallel passage, -°°° pilot operated valve, -...valve body, -...
・・Neutral flow path, m−−°° actuator port, −・・
・Communication passage, (to) pilot operated valve, 11@■...Load check poppet, Sakaki...piston, m-m-・
...Pilot pressure.

Representative Patent Attorney Nobuyuki Shizuku

Claims (1)

[Claims] At least two actuators are created by the x pumps, and a control valve corresponding to each of these seven actuators is provided, and these control valves connect their neutral flow paths in tandem. II! On the other hand, in the hydraulic circuit connected in parallel via the barrel two-bar passage r, a free tlL passage and a pilot-operated valve t-, which can be operated repeatedly, are provided in the Koji parallel passage*, This pilot operation valve is guided to the operating pressure of one of the actuators, the operating pressure of the rotary θ actuator, and the t pilot pressure. Rui I! Samrui F
The hydraulic circuit 7 is configured to be switched to either of the ridged passage positions, and the pressure valve connected in tandem with the pulp of the valve, and the parallel passage connected in parallel with other valves. Then, according to the control valve ν provided with a continuous passage that delays this parallel passage to the actuator boat according to the sm of the spool, only #:, :Iji from the parallel passage to the continuous passage is allowed. A load check poppet, a piston provided opposite to the load check poppet θ that acts as a pressure force, and a pilot chamber ′ formed on both sides with this piston as a mound are used to control the ratio pilot operation valve. In addition to being provided in the main body, one pilot chamber is configured to receive pilot pressure from the parallel passage, and the other pilot chamber is configured to receive pilot pressure of the actuator which is controlled by another control valve. The movement position of the piston is added according to the differential pressure in both pilot chambers, and the piston at position 7 controls the lift of the load check poppet.