JP2007032790A - Fluid pressure controller, fluid pressure control method, and hydraulic controller - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fluid pressure controller, a fluid pressure control method, and a hydraulic controller for improving operation property of a fluid pressure actuator while increasing efficiency of supply of hydraulic fluid by a simple configuration. <P>SOLUTION: This fluid pressure controller is provided with a first fluid pressure pump 2a and a second fluid pressure pump 2b, the fluid pressure actuator 4c driven by pressure fluid from the first fluid pressure pump 2a, a fluid pressure motor 4e driven by pressure fluid from the second fluid pressure pump 2b, an operation amount detection sensor 10a for detecting amount of operation of the fluid pressure motor 4e, a connection fluid passage 7 for connecting a supply passage 3a from the first fluid pressure pump 2a with a supply passage 3b from the second fluid pressure pump 2b, and a connection fluid passage control valve 8 provided in the connection fluid passage 7 to reduce amount of circulation of hydraulic fluid in the connection fluid passage 7 in accordance with the results of detection by the operation amount detection sensor 10a. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a fluid pressure control device and a fluid pressure control method suitable for controlling a fluid pressure circuit applied to a work machine, and a hydraulic control device for controlling a hydraulic circuit.

  Conventionally, work machines (hydraulic excavators, etc.) have been developed that include fluid pressure actuators such as hydraulic cylinders and hydraulic motors on the fluid pressure circuit, and that actuate fluid pressure devices such as buckets, booms, sticks, and swivels using the fluid pressure actuators. ing. In such a working machine, hydraulic fluid pressurized by a hydraulic pump is supplied to various hydraulic devices via a hydraulic circuit, and supplied to the hydraulic device by a control valve interposed between the hydraulic pump and the hydraulic device. The flow rate and hydraulic pressure of the hydraulic fluid to be used are appropriately controlled.

  For example, Patent Document 1 discloses two types of engine driving that supply hydraulic oil to actuators such as a hydraulic cylinder that drives a boom and a stick, a hydraulic motor that drives a traveling device and a turning device, and each hydraulic cylinder and hydraulic motor. In a hydraulic circuit including a hydraulic pump and a plurality of control valves for controlling the amount of hydraulic oil supplied to each actuator, an electronic control device (controller) for controlling the opening degree of each control valve is provided. Are listed.

  The hydraulic circuit described in Patent Document 1 includes a pressure sensor that detects discharge pressures of two hydraulic pumps, and a pressure that detects operating hydraulic pressure (that is, load pressure) on an oil passage between a control valve and each actuator. A sensor is provided, and an operation lever for setting the operation amount of each actuator is provided in the operation room (cab). Then, based on the hydraulic pressure input from each pressure sensor and the operation amount of the operation lever, the opening control of each control valve is performed, and each actuator is operated appropriately.

In such a hydraulic circuit, a combined hydraulic circuit has been developed in which a plurality of hydraulic circuits including a hydraulic pump, a control valve, and an actuator are provided and connected.
FIG. 5 shows a schematic circuit diagram of a two-pump merging hydraulic circuit in a conventional work machine. The two-pump merging hydraulic circuit includes two variable displacement hydraulic pumps 2a and 2b that are driven by the power of the engine 1, and hydraulic fluid discharged from these hydraulic pumps 2a and 2b is It is supplied to each hydraulic device of the work machine via a hydraulic control valve (control valve). Here, as a hydraulic device mounted on the work machine, a stick device and a turning device are shown as examples. In addition, the operation amount of each hydraulic device is set according to the lever operation amount of the operator, and the work machine is provided with an operation lever corresponding to each hydraulic device.

  The hydraulic pump 2a mainly supplies hydraulic oil to the stick hydraulic cylinder 4c that drives the stick device of the work machine. On the other hand, the hydraulic pump 2b mainly supplies hydraulic oil to the swing hydraulic motor 4e that drives the swing device. The hydraulic oil circuit (A circuit 3a) discharged from the hydraulic pump 2a and the hydraulic oil circuit (B circuit 3b) discharged from the hydraulic pump 2b are connected to each other by a connecting passage 7. As a result, when there is a surplus in the hydraulic oil supplied to each circuit, the hydraulic oil can be complemented to each other and efficiently supplied to various hydraulic devices.

A typical construction of the working machine is shown in FIG. 4. The working machine 30 includes a lower traveling body 31 having crawler devices 37 and 38 having an endless track, and an upper portion of the lower traveling body 31 via a turning device 39. And an upper revolving body 32 placed on the head. The upper swing body 32 is provided with a working device 33 and a cab 40 on which an operator rides. The working device 33 includes a boom 34 pivotally attached to the upper swing body 32 so as to be pivotable in the vertical direction, a stick 35 pivotally connected in a vertical plane at the tip of the boom 34, and It is comprised from the bucket 36 connected with the front-end | tip. The aforementioned swing hydraulic motor 4e is a hydraulic motor that rotationally drives the swing device 39, and the aforementioned stick hydraulic cylinder 4c is a hydraulic cylinder that drives the stick 35.
JP 2000-309950 A

  By the way, various large and small load pressures act on the actuators of various hydraulic devices arranged on the hydraulic circuit depending on the work contents and work conditions. For example, as shown in FIG. 4, when performing excavation of the earth and sand groove surface using the work machine 30, in the operation of forming the wall surface 21 of the excavation groove, the swiveling device 39 is swung in the direction of the wall surface to be formed to Sticking in (stick hydraulic cylinder extension) is performed while pressing the side surface against the wall surface 21 to perform the operation of forming the wall surface 21 flat.

  At this time, in order to form the wall surface 21 vertically, the rotation operation of the stick 35 is performed while pressing the side surface of the bucket 36 against the wall surface 21, but against the load of the swing hydraulic motor 4 e that drives the swing device 39. When the load pressure of the stick hydraulic cylinder 4c is low, the hydraulic oil to be supplied from the hydraulic pump 2b to the swing hydraulic motor 4e flows into the stick hydraulic cylinder 4c via the connecting passage 7 and is supplied to the swing hydraulic motor 4e. Oil flow will decrease. Therefore, there is a problem that a sufficient pressing force against the wall surface 21 is not generated and good operability cannot be obtained.

In other words, during normal work, the connecting oil 7 is provided to allow the A circuit 3a and the B circuit 3b to communicate with each other, so that the hydraulic oil supply efficiency can be increased. In some cases, the flow of hydraulic oil through the connecting passage 7 may be reduced and the operability may be reduced.
The present invention has been made in view of such a problem, and a fluid pressure control device capable of improving the operability of a fluid pressure actuator while improving the supply efficiency of hydraulic oil with a simple configuration, and An object of the present invention is to provide a fluid pressure control method and a hydraulic control device.

  In order to achieve the above object, a fluid pressure control device according to the present invention (Claim 1) supplies a pressure fluid as a working fluid of a fluid pressure circuit in a work machine equipped with a fluid pressure driven work device and a turning device. A first fluid pressure pump and a second fluid pressure pump, a fluid pressure actuator driven by the pressure fluid supplied from the first fluid pressure pump to operate the work device, and the second fluid pressure pump. A fluid pressure motor driven by the pressure fluid to operate the swivel device, an operation amount detection sensor for detecting an operation amount of a fluid pressure motor operation device for setting an operation amount of the fluid pressure motor, and the first fluid pressure A pressure fluid supply passage supplied from the pump and a pressure fluid supply passage supplied from the second fluid pressure pump; a connection fluid passage that is interposed in the connection fluid passage; Flow A connected fluid path control valve for controlling the flow rate of the pressure fluid to be operated, and the connected fluid path control valve increases the communication fluid path as the operation amount of the fluid pressure motor detected by the operation amount detection sensor increases. The flow rate of the pressure fluid that circulates is reduced.

The fluid pressure circuit here refers to a circuit in general that uses a fluid whose volume does not change substantially in response to a predetermined pressure change. For example, as a fluid pressure pump, a hydraulic pump, a hydraulic pump, etc. Includes those with hydraulic pumps. The fluid pressure actuator includes a hydraulic motor, a hydraulic cylinder, and the like.
Further, it is preferable that the connection fluid control valve completely closes the communication fluid path when the operation amount of the fluid pressure motor detected by the operation amount detection sensor is a predetermined amount or more. ).

  The hydraulic control device according to the present invention (Claim 3) includes a first hydraulic pump and a second hydraulic pump that supply hydraulic fluid of a hydraulic circuit in a work machine equipped with a hydraulically driven work device and a turning device, A hydraulic actuator that is driven by the hydraulic oil supplied from the first hydraulic pump to operate the work equipment; a hydraulic motor that is driven by the hydraulic oil supplied from the second hydraulic pump to operate the swivel device; A turning operation amount detection sensor for detecting an operation amount of a turning operation lever for setting an operation amount of the hydraulic motor, a supply passage for hydraulic oil supplied from the first hydraulic pump, and an operation supplied from the second hydraulic pump A connecting passage for connecting an oil supply passage and a combiner valve interposed in the connecting passage for controlling the flow rate of the hydraulic oil flowing through the connecting passage. The larger the operation amount of the hydraulic motor detected by the work amount detection sensor is characterized by reducing the flow rate of the hydraulic oil flowing in the said connection path.

  The fluid pressure control method according to the present invention (Claim 4) includes a first fluid pressure pump and a second fluid pressure pump for supplying a pressure fluid as a working fluid in a work machine equipped with a fluid pressure driven work device and a turning device. A fluid pressure pump; a fluid pressure actuator driven by the pressure fluid supplied from the first fluid pressure pump to operate the work equipment; and a swivel driven by the pressure fluid supplied from the two fluid pressure pumps. A fluid pressure motor for operating the device, a connecting fluid passage connecting a supply passage for the pressure fluid supplied from the first fluid pressure pump and a supply passage for the pressure fluid supplied from the second fluid pressure pump; A fluid pressure control method for a fluid pressure circuit comprising a connected fluid path control valve interposed in a connected fluid path and controlling a flow rate of a pressure fluid flowing through the connected fluid path, and the operation of the fluid pressure motor Set quantity The amount of operation of the fluid pressure motor operating device is detected, and the greater the amount of operation of the fluid pressure motor detected by the operation amount detection sensor, the smaller the flow rate of the pressure fluid flowing through the communication fluid path. It is a feature.

  According to the fluid pressure control device and the fluid pressure control method of the present invention (Claims 1 and 4), when the fluid pressure motor that drives the swivel device is not in operation, by the flow of the pressure fluid through the connected fluid path control valve, Pressure fluid can be supplied efficiently. Further, when the fluid pressure motor is operated, the flow rate of the pressure fluid through the connected fluid path control valve is decreased, whereby the flow of the pressure fluid to the fluid pressure actuator having a low load pressure can be suppressed. Therefore, the flow rate of the pressure fluid to the fluid pressure motor having a high load pressure can be increased, and the operability of the fluid pressure actuator can be improved.

  According to the fluid pressure control device of the present invention (Claim 2), since the connected fluid control valve is completely closed when the operation amount of the fluid pressure motor exceeds a predetermined amount, the pressure applied to the fluid pressure actuator with a low load pressure is reduced. The inflow of fluid can be prevented. Therefore, the flow rate of the pressure fluid to the fluid pressure motor having a high load pressure can be secured, and the operability of the fluid pressure actuator can be further improved.

  According to the hydraulic control device of the present invention (Claim 3), the operability of the hydraulic motor having a high load pressure can be improved. For example, it is possible to improve work operability at the time of forming an excavation wall surface that performs excavation while turning the work machine and pressing the bucket side face.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 4 show a fluid pressure control apparatus as one embodiment of the present invention.
FIG. 1 is a hydraulic circuit diagram of a hydraulic circuit to which the present apparatus is applied, FIG. 2 is a graph showing a relationship between a swing lever operation amount and a combiner valve opening in the hydraulic circuit shown in FIG. 1, and FIG. 3 is a hydraulic pressure shown in FIG. FIG. 4 is a perspective view showing an overall configuration of a work machine for forming a wall surface of a digging groove. FIG. 4 is a graph showing the relationship between the relief pressure in the circuit and the lever operation amount.

[overall structure]
This hydraulic control device (fluid pressure control device) is applied to a hydraulic excavator 30 as shown in FIG. The hydraulic excavator 30 includes an upper swing body 32, a lower traveling body 31, and a working device 33. The lower traveling body 31 is provided with a pair of left and right crawler devices 37 and 38 each having an endless track. The upper swing body 32 is placed on the upper portion of the lower travel body 31 via a swiveling device 39 and supported by the lower travel body 31 so as to be able to swing in the horizontal direction.

The working device 33 includes a boom 34, a stick (arm) 35, and a bucket 36. The boom 34 is pivotally attached to the upper swing body 32 so as to be pivotable in the vertical direction, and an arm 35 is connected to the tip of the boom 34 so as to be rotatable in the same vertical plane. A bucket 36 is connected to be rotatable in the direction.
Two boom hydraulic cylinders 4b for swinging and driving the boom 34 in the vertical direction are provided between the upper swing body 32 and the boom 34, and a stick 35 is provided between the boom 34 and the stick 35. Is provided between the stick 35 and the bucket 36. Further, a bucket hydraulic cylinder for swinging the bucket 36 at the tip of the stick 35 is provided between the stick 35 and the bucket 36. 4d is provided. Hereinafter, the boom 34, the stick 35, the bucket 36, the pair of left and right crawler devices 37 and 38, and the turning device 39 are collectively referred to as various hydraulic devices.

Further, the upper swing body 32 is provided with a cab 40 on which an operator gets on. The cab 40 includes a plurality of operation levers (including operation pedals) for setting operation amounts of various hydraulic devices 34 to 39. ) Is provided. Among these operation levers, the operation lever 9a of the turning device 39 and the operation lever 9b of the stick 35 are shown in FIG.
The turning operation lever 9a is an operation lever for setting an operation amount of a turning hydraulic motor 4e described later. The stick operation lever 9b is an operation lever for setting the operation amount of the stick hydraulic cylinder 4c. These operation levers are provided with lever sensors 10a and 10b for detecting an operation amount. The lever sensors 10a and 10b respectively provide the operation amounts A ₁ and A ₂ of the turning operation lever 9a and the stick operation lever 9b. Detected and input to the controller 11 described later.

  The hydraulic control apparatus is a hydraulic circuit for driving these various hydraulic apparatuses, and is applied to the hydraulic circuit shown in FIG. In addition, the same code | symbol is attached | subjected about the component same as the component described in FIG.

[Circuit configuration]
As shown in FIG. 1, this hydraulic circuit is a two-pump merging hydraulic circuit, and two variable displacement hydraulic pumps (fluid pressure pumps) that are driven by the power of the engine 1 that is a drive source of the work machine 30. ) 2a and 2b. The hydraulic fluid discharged from these hydraulic pumps 2a and 2b is supplied to hydraulic actuators (fluid pressure actuators) such as hydraulic motors and hydraulic cylinders via control valves (control valves).

  First, the hydraulic pump 2a mainly supplies hydraulic oil to the attachment hydraulic cylinder 4a, the stick hydraulic cylinder 4c that drives the stick 35, and the right crawler hydraulic motor 4f that drives the right crawler device 37. The hydraulic pump 2b mainly supplies hydraulic oil to the boom hydraulic cylinder 4b, the bucket hydraulic cylinder 4d, the turning hydraulic motor 4e that drives the turning device 39, and the left crawler hydraulic motor 4g that drives the left crawler device 38.

  With respect to the hydraulic cylinder, for example, when the stick hydraulic cylinder 4c operates in the extending direction, the tip of the stick 35 moves in the stick-in direction (rear side of the machine body of the work machine 30) in FIG. On the other hand, when the stick hydraulic cylinder 4c operates in the reduction direction, the tip of the stick 35 moves in the stick-out direction (front of the machine body of the work machine 30) in FIG.

  The circuit of hydraulic oil discharged from one hydraulic pump 2a is shown as A circuit 3a in a dashed box in FIG. 1, and the circuit of hydraulic oil discharged from the other hydraulic pump 2b is shown in the same dashed box. Shown as B circuit 3b. The A circuit 3a and the B circuit b3 are connected to each other through the connecting passage 7 so that hydraulic fluid can flow. In this way, by connecting both circuits to which hydraulic oil is supplied by the two hydraulic pumps 2a and 2b, when there is a surplus in the hydraulic oil supplied to each circuit, they complement each other. The hydraulic oil can be efficiently supplied in accordance with the operation state of the hydraulic actuator.

  Further, a combiner valve (a connection passage control valve) 8 is interposed on the connection passage 7. The combiner valve 8 is configured as a spool valve capable of continuously switching the stem position, and the opening of the valve is adjusted by controlling the stem position via a pilot circuit (not shown). The opening of the combiner valve 8 is variable and is controlled by the controller 11.

  The electromagnetic relief valves 5a and 5b are electromagnetic relief valves that limit the hydraulic pressure upper limit value of the hydraulic fluid flowing through each of the A circuit 3a and the B circuit 3b, and the relief pressure of each circuit is based on the input electric signal. To change. Here, the relief pressure is set based on the correspondence shown in FIG. 3 according to the operation amount of the operation lever of the various hydraulic devices. For example, the electromagnetic relief valve 5a arranged on the circuit relating to the hydraulic pump 2a refers to the operation amount of the operation lever (operation pedal) and the stick operation lever 9b of the right crawler traveling device, and is on the circuit relating to the hydraulic pump 2b. The arranged electromagnetic relief valve 5b sets the relief pressure with reference to the operation amounts of the operation lever (operation pedal) and the turning operation lever 9a of the left crawler traveling device.

The relief valve 13 is a relief valve that limits the upper limit value of the operating hydraulic pressure of the entire hydraulic circuit. The relief valve 13 functions as a safety valve for relieving the hydraulic oil when the hydraulic pressure exceeds a predetermined pressure larger than the relief pressure set by the electromagnetic relief valves 5a and 5b.
On the hydraulic oil supply passages from the two hydraulic pumps 2a and 2b to the various hydraulic devices, a straight switching valve 12 is provided. The straight-ahead switching valve 12 is a switching valve for switching the flow direction of the hydraulic oil discharged from the hydraulic pumps 2a and 2b.

  The linear switching valve 12 is configured so that the hydraulic oil supplied to the right crawler hydraulic motor 4f and the hydraulic oil supplied to the left crawler hydraulic motor 4g are individually supplied from the two hydraulic pumps 2a and 2b. Or, it is switched whether to supply from the same hydraulic pump. In other words, each crawler hydraulic motor requires a large amount of hydraulic oil to drive the crawler, and the load applied to the hydraulic pumps 2a and 2b tends to increase. Therefore, when driving a normal crawler, the crawler hydraulic motors 4f and 4g In a situation where the hydraulic circuit to which the hydraulic pumps are individually applied is formed to distribute the load applied to the hydraulic pumps, while the crawler linearity is required, the left and right crawler hydraulic motors 4f and 4g are A hydraulic circuit to which one hydraulic pump (one of the two hydraulic pumps) is applied is formed so that the left and right crawler driving force can be generated.

  For example, when the control spool of the rectilinear switching valve 12 is in the position shown in FIG. 1, the hydraulic fluid from the hydraulic pump 2a is mainly supplied to the right crawler hydraulic motor 4f, and the left crawler hydraulic motor 4g is supplied to the left crawler hydraulic motor 4g. The hydraulic oil is mainly supplied from the hydraulic pump 2b. Further, when the rectilinear switching valve 12 is switched, mainly the hydraulic oil from the hydraulic pump 2a is supplied to both the right crawler hydraulic motor 4f and the left crawler hydraulic motor 4g.

  The control valves 6a to 6g are provided corresponding to the respective hydraulic cylinders and the respective hydraulic motors 4a to 4g. Here, as shown in FIG. 1, the position of the stem (flow rate control spool) is continuously set at three positions. It is configured as a spool valve that can be switched between. The opening degree of these control valves 6 a to 6 g is controlled by the controller 11. The control valves 6a to 6g shown here are examples given as valves for controlling the amount of hydraulic oil supplied to each hydraulic cylinder and each hydraulic motor 4a to 4g.

In addition, as shown in FIG. 1, the controller 11 of the present embodiment performs the opening degree control of the combiner valve 8 according to the operation amount of the turning operation lever 9 a.
First, when the turning operation lever 9a of the turning hydraulic motor 4e is not operated, the controller 11 opens the combiner valve 8 (valve opening degree 100%) and performs control to join the A circuit 3a and the B circuit 3b. . That is, in this case, the circuit shape is the same as that of a conventional two-pump merging hydraulic circuit.

On the other hand, when the swing operation lever 9a of the hydraulic swing motor 4e is operated, the controller 11 performs control so as to narrow the combiner valve 8 the larger the operation amount A _1. Then, control is performed so that the A circuit 3a and the B circuit 3b are not merged when the turning operation lever 9a is fully operated (full lever state) and is completely closed (valve opening degree 0%).
Here, correspondence relationship between the operation amount of the valve opening and the pivot lever 9a of the combiner valve 8 are set as shown in FIG. 2, and the operation amount A ₁ and valve opening of the control lever 4e The setting is approximately inversely proportional.

[Action]
With the configuration as described above, the fluid pressure control device according to the present embodiment operates as follows.
First, when the turning operation lever 9a of the turning hydraulic motor 4e is not operated, the opening degree is not adjusted while the combiner valve 8 is opened. Therefore, the A circuit 3a and the B circuit 3b are joined together to complement each other when surplus occurs in the hydraulic fluid supplied to each of the A and B circuits 3a and 3b as in the prior art.

On the other hand, turning the turning operation lever 9a of the hydraulic motor 4e is operated, the opening of the operation amount A ₁ larger the combiner valve 8 is throttled, completely and closed A circuit 3a and B circuit during full lever state 3b is not merged.
For example, when forming the wall surface of the excavation groove as shown in FIG. 4, the turning operation lever 9a is operated to press the side surface of the bucket 36 against the wall surface 21, and the stick operation lever 9b is operated to stick the stick 35 to the stick-in. Driven in the direction. At this time, as the operation amount A ₁ of the swing operation lever 9a of the swing hydraulic motor 4e increases, the opening degree of the combiner valve 8 is reduced and flows through the connecting passage 7 between the A circuit 3a and the B circuit 3b. The amount of hydraulic oil to be reduced will decrease. As a result, the amount of hydraulic fluid flowing from the B circuit 3b side to the A circuit 3a side via the combiner valve 8 is reduced.

  Further, as shown in the graph of FIG. 2, the opening degree of the combiner valve 8 is reduced as the operation amount of the turning operation lever 9a is increased. When the turning operation lever 9a is in the full lever state, the combiner valve 8 is completely closed. As a result, the A circuit 3a and the B circuit 3b are completely separated and independent.

[effect]
As described above, according to the above-described embodiment, when the operation lever 9a of the swing hydraulic motor 4e is not operated, the combiner valve 8 can be opened to join the A and B circuits 3a and 3b. The supply efficiency of the hydraulic oil in the circuit can be improved.

  On the other hand, the combiner valve 8 can be throttled when the operation lever 9a of the swing hydraulic motor 4e is operated. That is, the flow of hydraulic oil between the A and B circuits 3a and 3b can be suppressed. Accordingly, when the wall surface of the excavation groove as shown in FIG. 4 is formed, even if the load pressure of the stick hydraulic cylinder 4c is low, the hydraulic oil to be supplied from the hydraulic pump 2b to the swing hydraulic motor 4e is reduced. Inflow from the B circuit 3b to the A circuit 3a side can be suppressed.

Further, as A _{1 of the} operating lever 9a increases and the required pressing force against the wall surface 21 increases, the flow rate of hydraulic oil flowing from the B circuit 3b to the A circuit 3a side can be further reduced, and the swing hydraulic motor 4e. The flow rate of hydraulic oil supplied to the When the operation lever 9a is fully operated, the A circuit 3a and the B circuit 3b can be completely separated, and the flow rate of hydraulic oil supplied to the turning hydraulic motor 4e can be ensured. A sufficient pressing amount with respect to 21 can be generated.

  Thus, according to the present invention, the opening degree control of the combiner valve 8 that accurately reflects the operator's intention to operate can be performed, and the operability of the hydraulic control device can be improved.

[Others]
Although the embodiment of the present invention has been described above, the present invention is not limited to this embodiment, and various modifications can be made without departing from the spirit of the present invention.

In the above-described embodiment, when the opening degree of the combiner valve 8 is adjusted, the connection passage 7 is controlled to be completely opened (valve opening degree 100%) to completely closed (valve opening degree 0%) according to the condition of the lever operation amount. However, it may be configured not only to completely open or completely close, but also to control to a predetermined opening set in advance, or to open and close in stages.
That is, the opening degree of the combiner valve 8 with respect to the lever operation amount A ₁ is not limited to the corresponding relationship as shown in FIG. 2, and the hydraulic oil that circulates through the combiner valve 8 as the lever operation amount increases. Correspondence should just be given so that a circulation amount may decrease.

In the above-described embodiment, the means for specifically controlling the combiner valve 8 is arbitrary and is not limited to the configuration including the controller 11. For example, the operation amount A ₁ detected by the lever sensor 10a may be directly input to the combiner valve 8 so that the valve opening degree is controlled.
Moreover, although the control valves 6a to 6g shown in the above-described embodiment are configured as spool valves, this is a valve for controlling the amount of hydraulic oil supplied to actuators (hydraulic motors) of various hydraulic devices. This is an example, and any valve having any structure can be applied as long as it is a variable throttle valve that variably controls the flow rate of hydraulic fluid flowing in the circuit.

  In the above-described embodiment, the present invention is applied to a hydraulic control device for controlling hydraulic oil in a hydraulic circuit. However, the control device controls the pressure levels of various fluids other than hydraulic fluid. It is applicable to. In addition, here, the fluid pressure control device according to the present invention is applied to a work machine, but can be applied to control of various machines using fluid pressure.

1 is a hydraulic circuit diagram of a hydraulic circuit to which a fluid pressure control device as one embodiment of the present invention is applied. It is a graph which shows the relationship between the turning lever operation amount and the combiner valve opening degree in the hydraulic circuit shown in FIG. It is a graph which shows the relationship between the relief pressure and lever operation amount in the hydraulic circuit shown in FIG. It is a perspective view which shows the whole structure of the working machine which performs wall surface shaping | molding of a digging groove. It is a typical circuit diagram of a two-pump merging hydraulic circuit in a conventional work machine.

Explanation of symbols

1 Engine 2a, 2b Hydraulic pump (fluid pressure pump)
3a A circuit 3b B circuit 4a to 4d Hydraulic cylinder (fluid pressure actuator)
4e-4g Hydraulic motor (fluid pressure motor)
5a, 5b Electromagnetic relief valve 6a-6g Control valve 7 Connection passage (connection fluid passage)
8 Combiner valve (connected fluid path control valve)
9a Stick operation lever 9b Rotation operation lever 10a, 10b Lever sensor 11 Controller 12 Linear switching valve 13 Relief valve 30 Work machine 31 Lower traveling body 32 Upper revolving body 33 Working device 34 Boom 35 Stick (arm)
36 bucket 37 right crawler device 38 left crawler device 39 swivel device 40 cab

Claims (4)

A first hydraulic pressure pump and a second hydraulic pressure pump for supplying a pressure fluid as a working fluid of a fluid pressure circuit in a working machine equipped with a fluid pressure driven working device and a turning device;
A fluid pressure actuator driven by the pressure fluid supplied from the first fluid pressure pump to operate the work equipment;
A fluid pressure motor driven by the pressure fluid supplied from the two fluid pressure pump to operate the swivel device;
An operation amount detection sensor for detecting an operation amount of a fluid pressure motor operation device for setting an operation amount of the fluid pressure motor;
A connecting fluid passage that connects a supply passage for the pressure fluid supplied from the first fluid pressure pump and a supply passage for the pressure fluid supplied from the second fluid pressure pump;
A connection fluid path control valve that is interposed in the connection fluid path and controls the flow rate of the pressure fluid flowing through the connection fluid path;
The fluid connection control valve is configured to reduce the flow rate of the pressure fluid flowing through the communication fluid path as the operation amount of the fluid pressure motor detected by the operation amount detection sensor increases. Pressure control device. The connected fluid control valve completely closes the communication fluid path when the operation amount of the fluid pressure motor detected by the operation amount detection sensor is a predetermined amount or more. The fluid pressure control apparatus described. In a working machine equipped with a hydraulically driven work device and a turning device, a first hydraulic pump and a second hydraulic pump for supplying hydraulic fluid of a hydraulic circuit;
A hydraulic actuator that is driven by the hydraulic oil supplied from the first hydraulic pump to operate the work equipment;
A hydraulic motor driven by the hydraulic oil supplied from the second hydraulic pump to operate the swivel device;
A turning operation amount detection sensor for detecting an operation amount of a turning operation lever for setting an operation amount of the hydraulic motor;
A connecting passage for connecting a supply passage for hydraulic oil supplied from the first hydraulic pump and a supply passage for hydraulic oil supplied from the second hydraulic pump;
A combiner valve that is interposed in the connection passage and controls the flow rate of the hydraulic oil flowing through the communication passage;
The hydraulic control device according to claim 1, wherein the combiner valve decreases the flow rate of the hydraulic oil flowing through the connection passage as the operation amount of the hydraulic motor detected by the turning operation amount detection sensor is larger. In a working machine equipped with a fluid pressure-driven working device and a turning device, a first fluid pressure pump and a second fluid pressure pump that supply pressure fluid as a working fluid, and the first fluid pressure pump that is supplied from the first fluid pressure pump A fluid pressure actuator driven by pressure fluid to actuate the work device, a fluid pressure motor driven by the pressure fluid supplied from the two fluid pressure pump to actuate the swivel device, and the first fluid pressure pump. A connecting fluid path connecting the supply passage of the pressure fluid supplied and the supply path of the pressure fluid supplied from the second fluid pressure pump; and the connecting fluid path interposed in the connecting fluid path. A fluid pressure control method for a fluid pressure circuit including a connected fluid path control valve for controlling a flow rate of a pressure fluid,
Detecting the operation amount of the fluid pressure motor operating device for setting the operation amount of the fluid pressure motor;
A fluid pressure control method, characterized in that the larger the operation amount of the fluid pressure motor detected by the operation amount detection sensor, the smaller the flow rate of the pressure fluid flowing through the communication fluid path.

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