JP6656994B2 - Working machine hydraulic system - Google Patents

Description

  The present invention relates to a hydraulic system for a working machine such as a skid steer loader and a compact truck loader.

Conventionally, as a hydraulic system of a working machine such as a skid steer loader and a compact truck loader, Patent Document 1 is known.
The hydraulic system of Patent Document 1 switches an HST motor capable of switching between low speed (first speed) and high speed (second speed), a hydraulic switching valve capable of switching the HST motor to first speed or second speed, and a hydraulic switching valve. A direction switching valve. In addition, the hydraulic system includes an HST pump that can change the angle of the swash plate by operating the travel lever and that can change the supply amount of hydraulic oil to the HST motor according to the angle of the swash plate.

JP 2013-36276 A

  In the hydraulic system, an attempt has been made to change the direction switching valve to an electromagnetic proportional valve and to switch the hydraulic switching valve with the pressure of hydraulic oil output from the electromagnetic proportional valve. When the directional control valve is an electromagnetic proportional valve, there is a possibility that the current for operating the electromagnetic proportional valve and the pressure of the hydraulic oil output from the electromagnetic proportional valve are different for each electromagnetic proportional valve. Also, when the swash plate of the HST motor is operated by the electromagnetic proportional valve, the relationship between the electromagnetic proportional valve and the angle of the swash plate may be different. In other words, there is a possibility that the relationship between the current and the pressure of the hydraulic oil is different for each work machine equipped with the electromagnetic proportional valve. That is, when the electromagnetic proportional valve is mounted, the operability (feel when operating) may be different for each work machine.

  The present invention has been made in order to solve the above-described problems of the related art, and has an object to provide a hydraulic system of a working machine capable of suppressing variation in operability between working machines. Aim.

The technical measures taken by the present invention to solve the above technical problem are as follows.
The hydraulic system of the working machine includes a hydraulic pump that discharges hydraulic oil, an operating valve that can change the pressure of the operating oil, a traveling hydraulic device whose operating state changes according to the operating oil of the operating valve, A first measurement device capable of detecting the pressure of the hydraulic oil acting on the device, an acquisition unit capable of acquiring a relationship between a control signal and the pressure of the hydraulic oil detected by the first measurement device, and the acquisition unit acquiring the relationship. A control unit having a storage unit that stores a relationship between a control signal and the pressure of hydraulic oil, and a control unit that controls the operating valve based on the relationship stored in the storage unit; the acquisition unit and the storage A switching device capable of switching between a first mode in which the unit operates and a second mode in which the control unit operates, and switching between a braking state for braking the traveling hydraulic device and a release state for releasing the braking state When possible and in the first mode Has a braking device in a braking state .
The hydraulic system of the working machine includes a hydraulic pump that discharges hydraulic oil, an operating valve that can change the pressure of the operating oil, a traveling hydraulic device whose operating state changes according to the operating oil of the operating valve, A first measurement device capable of detecting the pressure of the hydraulic oil acting on the device, an acquisition unit capable of acquiring a relationship between a control signal and the pressure of the hydraulic oil detected by the first measurement device, and the acquisition unit acquiring the relationship. A control unit having a storage unit that stores a relationship between a control signal and the pressure of hydraulic oil, and a control unit that controls the operating valve based on the relationship stored in the storage unit; the acquisition unit and the storage A switching device capable of switching between a first mode in which the unit operates and a second mode in which the control unit operates, wherein the operating valve is a proportional valve capable of changing the pressure of hydraulic oil, and The device is configured to move the first position and the second position in accordance with the opening of the proportional valve . A hydraulic switching valve that switches between two positions and an intermediate position, and switches to first speed when the hydraulic switching valve is in the first position and switches to second speed when the hydraulic switching valve is in the second position And a travel motor, wherein the first measuring device switches the hydraulic pressure switching valve from the intermediate position to the second position when increasing the travel motor from the first speed to the second speed. When the traveling motor is decelerated from the second speed to the first speed by detecting the pressure acting on the hydraulic switching valve in the first switching range, the hydraulic switching valve is moved from the intermediate position to the first position. Detecting the pressure acting on the hydraulic switching valve in the second switching range at the time of switching to the first mode, the acquisition unit, in the first mode, the pressure acting on the hydraulic switching valve in the first switching range, In the first switching range A relationship between the control signal output to the proportional valve and the first control signal is obtained, and the pressure acting on the hydraulic switching valve in the second switching range and the output to the proportional valve in the second switching range are obtained. The control unit obtains a relationship with a second control signal that is a control signal obtained by the control unit, and in the second mode, controls the proportional valve based on the pressure in the first switching range and the first control signal. The control of the proportional valve is performed based on the pressure in the second switching range and the second control signal .

The acquisition unit acquires a relationship between a control signal corresponding to an opening degree of the operating valve and a pressure of the operating oil in the first mode.
The operating valve is a proportional valve capable of changing the pressure of hydraulic oil, and the traveling hydraulic device includes a traveling motor that switches to a first speed or a second speed according to an opening degree of the proportional valve. One measuring device detects the pressure of the hydraulic oil acting on the hydraulic switching valve.

In the first mode, the obtaining unit obtains a relationship between the control signal corresponding to a predetermined range and a pressure of the hydraulic oil, and in the second mode, the control unit controls the travel motor. Is changed from the first speed to the second speed, the proportional valve is controlled based on the relationship between the control signal corresponding to the predetermined range and the pressure of the hydraulic oil.
In the first mode, the obtaining unit obtains a relationship between the control signal corresponding to a predetermined range and a pressure of the hydraulic oil, and in the second mode, the control unit controls the travel motor. Is changed from the second speed to the first speed, the proportional valve is controlled based on the relationship between the control signal corresponding to the predetermined range and the pressure of the hydraulic oil.

A brake device is provided which can be switched between a braking state for braking the traveling hydraulic device and a release state for releasing the braking state, and which is in a braking state when in the first mode.
The hydraulic system of the work machine detects an operating valve that can change the pressure of the operating oil, a traveling hydraulic device whose rotation speed changes according to the operating oil of the operating valve, and a rotation speed when the traveling hydraulic device is operated. A second measuring device capable of acquiring the relationship between the control signal and the rotational speed of the traveling hydraulic device detected by the second measuring device; a control signal acquired by the acquiring unit; A control unit having a storage unit that stores a relationship with the number of rotations of the device and a control unit that controls the operating valve based on the relationship stored in the storage unit; and the acquisition unit and the storage unit operate. A switching device capable of switching between a first mode and a second mode in which the control unit operates.

  A hydraulic pump that discharges hydraulic oil, an operating valve that operates based on a control signal and outputs operating oil, a traveling hydraulic device that operates according to the operating oil output from the operating valve, and changes the rotation speed, A second measuring device capable of detecting a rotational speed of the traveling hydraulic device during operation, and an acquiring unit capable of acquiring a relationship between the control signal and the rotational speed of the traveling hydraulic device detected by the second measuring device; A control device comprising: a storage unit that stores a relationship between a control signal obtained by the obtaining unit and a rotation speed of the traveling hydraulic device; and a control unit that controls the operating valve based on the relationship stored in the storage unit. And a switching device capable of switching between a first mode in which the acquisition unit and the storage unit operate and a second mode in which the control unit operates.

The operating valve is a proportional valve that can change the pressure of hydraulic oil, the traveling hydraulic device is a traveling hydraulic pump that can change the angle of a swash plate according to the operation of the proportional valve, and a traveling hydraulic pump. A travel motor whose rotation speed changes in accordance with the angle of the swash plate, wherein the second measuring device detects the rotation speed of the travel motor when the travel hydraulic pump is operating.
In the first mode, the acquisition unit acquires a relationship between the rotation speed of the traveling motor and the control signal when the rotation speed of the traveling motor is increased, and in the second mode, the control unit When increasing the rotation speed of the traveling motor, the proportional valve is controlled based on the relationship.

  In the first mode, the obtaining unit obtains a relationship between the rotation speed of the travel motor and the control signal when the rotation speed of the travel motor is reduced, and in the second mode, the control unit When decreasing the rotation speed of the traveling motor, the proportional valve is controlled based on the relationship.

  ADVANTAGE OF THE INVENTION According to this invention, the dispersion | variation in the operability for every working machine can be suppressed.

It is a figure showing a hydraulic system in a 1st embodiment. FIG. 9 is a diagram illustrating a first relationship between an output current and a detected pressure when the operating valve is changed from fully closed to fully open. It is a figure which shows the pressure (detection pressure) when changing from 1st speed to 2nd speed and when changing from 2nd speed to 1st speed. It is a figure showing a hydraulic circuit of a hydraulic system in a 2nd embodiment. It is a figure which shows the detection rotation speed at the time of changing an output current (swash plate) from minimum to maximum. FIG. 9 is a diagram illustrating a relationship between an output current and a detected rotation speed when changing from a low speed to a high speed. FIG. 9 is a diagram illustrating a relationship between an output current and a detected rotation speed when changing from a high speed to a low speed. It is a figure which shows the pressure (detection pressure) when changing from 1st speed to 2nd speed when there is no neutral position, and when changing from 2nd speed to 1st speed. It is a figure showing a hydraulic system provided with a braking device. It is a figure showing the side of a truck loader. It is a figure showing the side of a truck loader when a cabin is raised.

Hereinafter, a hydraulic system for a working machine according to an embodiment of the present invention will be described with reference to the drawings.
[First Embodiment]
The overall configuration of the working machine will be described. FIGS. 8 and 9 show a track loader as an example of the work machine 1. The working machine is not limited to a truck loader, and may be, for example, a tractor, a skid steer loader, a compact truck loader, a backhoe, or the like. In the present embodiment, the front side (the direction indicated by the arrow F shown in FIG. 8) of the driver sitting on the driver's seat of the work machine 1 is forward, and the rear side of the driver (the direction indicated by the arrow R shown in FIG. 8). , The left side of the driver (the front side as viewed in FIG. 8) is the left side, and the right side of the driver (the rear side as viewed in FIG. 8) is the right side.

  As shown in FIGS. 8 and 9, the working machine 1 includes a machine body 2, a working device 3 mounted on the machine body 2, and a traveling device 4 supporting the machine body 2. A cabin 5 is mounted on an upper part of the body 2 and at a front part of the body 2. A rear portion of the cabin 5 is supported by a support bracket 11 of the body 2 and is swingable around a support shaft 12. The front part of the cabin 5 can be supported by the front part of the body 2.

A driver's seat 13 is provided in the cabin 5. On one side (for example, left side) of the driver's seat 13, a traveling operation device 14 for operating the traveling device 4 is arranged.
The traveling device 4 is configured by a crawler traveling hydraulic device. The traveling device 4 is provided below the left side of the body 2 and below the right side of the body 2. The traveling device 4 can travel by the driving force of a hydraulically driven traveling hydraulic device 44 described later.

  The working device 3 includes a boom 22L, a boom 22R, and a bucket 23 (work implement) attached to a tip of the boom 22L and the boom 22R. The boom 22 </ b> L is arranged on the left side of the body 2. The boom 22 </ b> R is arranged on the right side of the body 2. The boom 22L and the boom 22R are interconnected by a connector (not shown) provided between the boom 22L and the boom 22R. The boom 22L and the boom 22R are supported by a first lift link 24 and a second lift link 25, respectively. A lift cylinder 26 composed of a double-acting hydraulic cylinder is provided between the base of the boom 22L and the boom 22R and the rear lower part of the body 2 so as to correspond to the boom 22L and the boom 22R. The boom 22L and the boom 22R simultaneously swing vertically by extending and retracting the lift cylinder 26 simultaneously. A mounting bracket 27 is pivotally connected to the distal ends of the booms 22L and 22R so as to be rotatable around a horizontal axis, and the back side of the bucket 23 is attached to the mounting bracket 27.

Further, a tilt cylinder 28 composed of a double-acting hydraulic cylinder is interposed between the mounting bracket 27 and the middle part on the distal end side of the boom 22L and the boom 22R corresponding to the boom 22L and the boom 22R. The bucket 23 swings (squeezes and dumps) by the expansion and contraction of the tilt cylinder 28.
The bucket 23 is detachable from the mounting bracket 27. When the mounting bracket 27 is detached from the bucket 23, various attachments (a hydraulically driven work tool having a hydraulic actuator) can be attached, and various operations other than excavation (or other excavation operations) can be performed. Have been.

A prime mover 29 is provided on the rear side of the bottom wall of the body (body) 2. The prime mover 29 is a diesel engine, a motor generator, or the like. A fuel tank 30 and a hydraulic oil tank 31 are provided on the front side on the bottom wall of the body 2. The body 2 is provided with a control valve (hydraulic control device) for the working device 3.
Next, the hydraulic system of the working machine will be described.

FIG. 1 is a diagram illustrating a hydraulic system of a traveling system of a working machine.
As shown in FIG. 1, the hydraulic system has a first hydraulic pump P1 and a second hydraulic pump P2. The first hydraulic pump P <b> 1 is used to drive a hydraulic actuator of an attachment attached to the distal end of the lift cylinder 26, the tilt cylinder 28, or the boom 22. The second hydraulic pump P2 (pilot pump, charge pump) is mainly used to supply hydraulic oil pressure as a control pressure or a signal pressure. Hereinafter, for convenience of explanation, hydraulic oil as control pressure or signal pressure is referred to as “pilot oil”, and pressure of pilot oil is referred to as “pilot pressure”.

  The hydraulic system has a traveling hydraulic device 44 and an operating valve 45. The traveling hydraulic device 44 is a device whose operating state changes according to the hydraulic oil output from the operating valve 45. Specifically, the traveling hydraulic device 44 is a device that can change the speed with hydraulic oil. That is, in the traveling hydraulic device 44, the rotation speed (rotation speed) of the traveling motor described later is changed. In other words, the traveling hydraulic device 44 is a device that can change the propulsion force when the traveling device 4 travels. The traveling hydraulic device 44 can change the speed between, for example, a first speed and a second speed which is higher than the first speed. In the present invention, the second speed indicates that the speed is higher than the first speed, and it is limited that the traveling hydraulic device 44 has only two types of rotation speeds (propulsion forces). Not a division. For example, when the switching of the rotation speed (propulsion force) of the traveling motor is divided into five stages, the rotation speed corresponding to the predetermined number of stages is the first speed, and the rotation speed of the number of stages larger than the predetermined number of stages is Second gear. In other words, the predetermined speed is the first speed (lower speed), and the speed higher than the predetermined speed is the second speed (upper speed).

The traveling hydraulic device 44 includes a first traveling hydraulic pump 66A, a second traveling hydraulic pump 66B, a first traveling motor 80A, a second traveling motor 80B, and a hydraulic switching valve 90. Note that the hydraulic switching valve 90 and the traveling hydraulic device 44 may be configured separately. The hydraulic switching valve 90 has a hydraulic switching valve 90A and a second hydraulic switching valve 90B.
The first traveling hydraulic pump 66A and the first traveling motor 80A are connected by a first circulation oil passage 101 that can circulate hydraulic oil. The second traveling hydraulic pump 66B and the second traveling motor 80B are connected by a second circulating oil passage 102 that can circulate hydraulic oil. The first hydraulic switching valve 90A and the first traveling motor 80A are connected by an oil passage 103, and the second hydraulic switching valve 90B and the second traveling motor 80B are connected by an oil passage 104. The first hydraulic switching valve 90A, the second hydraulic switching valve 90B, and the operating valve 45 are connected by an oil passage 105. The operating valve 45 and the second hydraulic pump P2 are connected by an oil passage 106. Note that the first traveling hydraulic pump 66A and the second traveling hydraulic pump 66B are connected to the second hydraulic pump P2 by an oil passage (not shown), and the hydraulic oil discharged from the second hydraulic pump P2 is used for the first traveling hydraulic pump P2. It can be supplied to the hydraulic pump 66A and the second traveling hydraulic pump 66B.

  The first traveling hydraulic pump 66A is a swash plate type variable displacement axial pump driven by the power of the prime mover 29. Further, the first traveling hydraulic pump 66A includes a pressure receiving portion 66a and a pressure receiving portion 66b on which pilot pressure acts. The angle of the swash plate can be changed by the pilot pressure acting on the pressure receiving portions 66a and 66b. When the angle of the swash plate changes, the discharge direction and discharge amount of the hydraulic oil change, thereby changing the rotation output of the first traveling motor 80A.

The second traveling hydraulic pump 66B has the same configuration as the first traveling hydraulic pump 66A. When the angle of the swash plate of the second traveling hydraulic pump 66B is changed, the discharge direction and the discharge amount of the working oil are changed, thereby changing the rotation output of the second traveling motor 80B.
The first traveling motor 80A is configured by a cam motor (radial piston motor). The first traveling motor 80A is a variable displacement type that can change the magnitude of the displacement (motor displacement) during operation, and can change the rotation and torque of the output shaft by changing the displacement of the motor. More specifically, the first traveling motor 80A has a first motor 81 and a second motor 82. By supplying the hydraulic oil to both the first motor 81 and the second motor 82, the motor capacity is increased, and the first traveling motor 80A is in the first speed. Further, by supplying the hydraulic oil to either the first motor 81 or the second motor 82, the motor capacity is reduced, and the first traveling motor 80 is set to the second speed. The second traveling motor 80B has the same configuration as the first traveling motor 80A, and can be changed to first speed or second speed.

  The first hydraulic switching valve 90A is a hydraulic switching valve that can be switched to a plurality of switching positions in accordance with a pilot pressure, which is a pressure of pilot oil, and is a valve that switches the first traveling motor 80A to first speed or second speed. , A first position 90a, a second position 90b, and a neutral position 90c. Specifically, when the pressure of the pilot oil acting on the pressure receiving portion 91 of the first hydraulic switching valve 90A is less than a predetermined pressure, which is a predetermined pressure, the hydraulic switching valve 90 is moved to the first position 90a by a spring. Will be retained. When the first hydraulic switching valve 90A is at the first position 90a, hydraulic oil is supplied to both the first motor 81 and the second motor 82, and the first traveling motor 80A is in the first speed. When the pressure of the pilot oil acting on the pressure receiving portion 91 of the first hydraulic switching valve 90A is equal to or higher than the set pressure, the first hydraulic switching valve 90A is switched to the second position 90b via the neutral position 90c. When the first hydraulic switching valve 90A is at the second position 90b, the operating oil is supplied only to the first motor 81, and the first traveling motor 80A is in the second speed.

The second hydraulic switching valve 90B has the same configuration as the first hydraulic switching valve 90A. The second hydraulic pressure switching valve 90B switches the second traveling motor 80B to first speed or second speed.
The operation valve 45 is a valve that operates based on a control signal output from the control device 110 to be described later and outputs hydraulic oil. The operation valve 45 changes an opening degree according to the control signal to change the pressure of the hydraulic oil. It is a proportional valve (proportional valve). For example, when the operating valve 45 is closed (fully closed state), the pilot pressure acting on the first hydraulic switching valve 90A and the second hydraulic switching valve 90B is substantially zero. As a result, the first hydraulic switching valve 90A and the second hydraulic switching valve 90B are at the first position 90a. When the operating valve 45 is gradually opened from the closed state and the opening of the operating valve 45 is increased, the pilot pressure acting on the first hydraulic switching valve 90A and the second hydraulic switching valve 90B changes according to the opening of the operating valve 45. Increase. When the opening of the operating valve 45 is increased until the pilot pressure acting on the first hydraulic switching valve 90A and the second hydraulic switching valve 90B exceeds a set value, the first hydraulic switching valve 90A and the second hydraulic switching valve 90B become , To the second position 90b via the neutral position 90c. That is, the opening degree of the operating valve 45 is proportional to the pilot pressure acting on the first hydraulic switching valve 90A and the second hydraulic switching valve 90B, and the first hydraulic switching valve 90A is increased with the opening degree of the operating valve 45. The switching position of the second hydraulic switching valve 90B can be changed.

  Now, as shown in FIG. 1, the oil passage 106 branches on the upstream side of the operating valve 45, and the oil passage 107 after the branch is connected to the traveling operation device 14. The travel operation device 14 includes a remote control valve 36 for forward movement, a remote control valve 37 for reverse travel, a remote control valve 38 for right turn, a remote control valve 39 for left turn, and a travel lever 40. Each of the remote control valves 36, 37, 38, and 39 is operated by a common, that is, one traveling lever 40. The remote control valves 36, 37, 38, 39 change the pressure of the hydraulic oil in accordance with the operation of the travel lever 40 (operation member) and supply the changed hydraulic oil to the travel hydraulic device 14. In this embodiment, the remote control valves 36, 37, 38, and 39 are operated by one traveling lever 40, but a plurality of traveling levers 40 may be used. For example, a first travel lever is disposed on one side (left side) of the driver's seat 13 and a second travel lever is disposed on the other side, and the remote control valves 36, 37, 38, 39 may be operated.

  The traveling lever 40 can be tilted from the neutral position in the front-rear direction, the width direction orthogonal to the front-rear direction, and the oblique direction. By tilting the travel lever 40, each remote control valve 36, 37, 38, 39 of the travel operation device 14 is operated. Then, a pilot pressure proportional to the operation amount from the neutral position of the traveling lever 40 is output from the secondary ports of the remote control valves 36, 37, 38, and 39.

  When the traveling lever 40 is tilted forward (in the direction of arrow A1 in FIG. 1), the forward remote control valve 36 is operated, and pilot pressure is output from the remote control valve 36. This pilot pressure acts on the pressure receiving portions 66a of the first traveling hydraulic pump 66A and the second traveling hydraulic pump 66B. As a result, the output shafts of the first traveling motor 80A and the second traveling motor 80B rotate forward (forward rotation) at a speed proportional to the amount of tilt of the traveling lever 40, and the work implement 1 moves straight forward.

  When the traveling lever 40 is tilted rearward (in the direction indicated by the arrow A2 in FIG. 1), the reverse remote control valve 37 is operated, and pilot pressure is output from the remote control valve 37. This pilot pressure acts on the pressure receiving portion 66b of the first traveling hydraulic pump 66A and the second traveling hydraulic pump 66B. As a result, the output shafts of the first traveling motor 80A and the second traveling motor 80B reversely rotate (reversely rotate) at a speed proportional to the amount of tilt of the traveling lever 40, and the work implement 1 moves straight backward.

  When the traveling lever 40 is tilted to the right (in the direction indicated by the arrow A3 in FIG. 1), the right turn remote control valve 38 is operated, and pilot pressure is output from the remote control valve 38. This pilot pressure acts on the pressure receiving portion 66a of the first traveling hydraulic pump 66A and also acts on the pressure receiving portion 66b of the second traveling hydraulic pump 66B. As a result, the output shaft of the first traveling motor 80A rotates forward and the output shaft of the second traveling motor 80B rotates reversely, and the work implement 1 turns to the right.

  When the traveling lever 40 is tilted to the left (in the direction of arrow A4 in FIG. 1), the remote control valve 39 for turning left is operated, and the pilot pressure is output from the remote control valve 39. This pilot pressure acts on the pressure receiving portion 66b of the first traveling hydraulic pump 66A and also acts on the pressure receiving portion 66a of the second traveling hydraulic pump 66B. Thereby, the output shaft of the first traveling motor 80A rotates in the reverse direction, and the output shaft of the second traveling motor 80B rotates in the forward direction, so that the work implement 1 turns left.

Further, when the traveling lever 40 is tilted in an oblique direction, the first traveling motor 80A and the second traveling motor 80A and the second traveling hydraulic pump 66B are caused by the differential pressure of the pilot pressure acting on the pressure receiving portions 66a and 66b of the second traveling hydraulic pump 66B. The rotation direction and rotation speed of the output shaft of the traveling motor 80B are determined, and the truck loader 1 turns right or left while moving forward or backward.
That is, when the traveling lever 40 is tilted forward and left diagonally, the work implement 1 turns left while moving forward at a speed corresponding to the tilt angle of the traveling lever 40. When the traveling lever 40 is tilted forward and obliquely to the right, the work implement 1 turns right while moving forward at a speed corresponding to the tilt angle of the traveling lever 40. When the traveling lever 40 is tilted leftward and rearward, the work implement 1 turns left while moving backward at a speed corresponding to the tilt angle of the traveling lever 40. When the traveling lever 40 is tilted to the right rear side, the work implement 1 turns right while moving backward at a speed corresponding to the tilt angle of the traveling lever 40.

  The control device 110 is a device that controls the operation valve 45, and includes, for example, a CPU and the like. The control device 110 can switch between at least the setting mode 110a and the control mode 110b. The setting mode 110a is a mode for performing various settings related to control. The control mode 110b is a mode for performing control. Switching between the setting mode 110a and the control mode 110b is performed by a switching device 111 connected to the control device 110. The switching device 111 is a switch or the like. For example, when the prime mover 29 is started, the control device 110 is set to the control mode 110b. When the switching device 111 is operated from this state, the control mode is switched from the control mode 110b to the setting mode 110a. Note that the method of switching between the control mode 110b and the setting mode 110a is not limited to the method described above. For convenience of description, the setting mode 110a is called a first mode, and the control mode 110b is called a second mode.

  In the first mode 110a, the relationship between the pressure of the hydraulic oil acting on the traveling hydraulic device 44 and the control signal from the control device 110 is set. In this embodiment, the pressure of the working oil acting on the traveling hydraulic device 44 is the pressure of the working oil acting on the hydraulic switching valves (the first hydraulic switching valve 90A and the second hydraulic switching valve 90B) of the traveling hydraulic device 44. is there. The pressure acting on the hydraulic switching valve of the traveling hydraulic device 44 is detected by a first measuring device 120 connected to the oil passage 105. Then, in the first mode 110a, the relationship between the pressure of the hydraulic oil detected by the first measuring device 120 and the control signal output from the control device 110 to the operating valve 45, that is, the current (referred to as the first relationship) is acquired. Then, the relationship between the pressure of the hydraulic oil and the current is stored. In the control mode 110b, the operation valve 45 is controlled based on the first relation.

Hereinafter, the setting mode and the control mode will be described together with the configuration of the control device 110.
The control device 110 includes an acquisition unit 112, a storage unit 113, and a control unit 114. The acquisition unit 112 and the control unit 114 are configured by programs and the like stored in the control device 110.
The acquisition unit 112 is operable in the first mode 110a, and acquires a first relationship between a control signal (for example, current) and a pressure (detected pressure) of hydraulic oil detected by the first measuring device 120. That is, when the first mode 110a is set by the switching device 111, the acquisition unit 112 acquires the first relationship between the control signal corresponding to the opening degree of the operating valve 45 and the detected pressure. Specifically, in the first mode 110, as shown in FIG. 2, the control device 110 changes the current output to the operating valve 45 from the current (minimum value) for fully closing the operating valve 45 to the operating valve 45. Change to the fully opened current (maximum value). The acquisition unit 112 acquires a current value of a predetermined output current and a detected pressure when the output current is changed from a minimum value to a maximum value. That is, the acquiring unit 112 acquires the first relationship between the predetermined opening degree (output current) and the detected pressure in a situation where the operating valve 45 changes from the fully closed state to the fully opened state. The storage unit 113 is operable in the first mode 110a, and stores the first relationship between the output current and the output pressure acquired by the acquisition unit 112.

In the above-described embodiment, in the case of the first mode 110a, the acquisition unit 112 acquires the first relationship between the control signal from when the operating valve 45 is fully opened to fully closed and the detected pressure, The control current and the detected pressure in a predetermined range may be acquired.
FIG. 3 shows the transition of the pressure when the first speed is switched to the second speed and when the second speed is switched to the first speed. As shown in FIG. 3, when the hydraulic switching valves (the first hydraulic switching valve 90A, the second hydraulic switching valve 90B) are switched from the first speed to the second speed, for example, the pressure of the hydraulic switching valve is controlled by the control device 110. Until the pressure reaches the first pressure and then reaches the second pressure. The acquisition unit 112 assumes that the hydraulic switching valve is changed from the first speed to the second speed, and detects the detected pressure in a predetermined range (first switching range S1) in which the pressure of the hydraulic switching valve increases from the first pressure to the second pressure. The relationship between the current and the current (first relationship) may be obtained. That is, when the first mode 110a is set, the control device 110 outputs the output current from around the first current value corresponding to the preset first pressure to around the second current value corresponding to the second pressure. To change. The acquisition unit 112 acquires an output current value in the first switching range S1 until the detected pressure changes from a preset first pressure to a second pressure, and a detected pressure. In this case, the storage unit 113 stores the output current value and the detected pressure in the first switching range S1.

On the other hand, as shown in FIG. 3, when the hydraulic switching valves (the first hydraulic switching valve 90A, the second hydraulic switching valve 90B) are switched from the second speed to the first speed, for example, the hydraulic switching valve is controlled by the control device 110. The pressure is gradually changed from when the pressure reaches the third pressure to when the pressure reaches the fourth pressure.
The acquisition unit 112 assumes that the hydraulic switching valve is changed from the second speed to the first speed, and detects the detected pressure in a predetermined range (second switching range S2) in which the pressure of the hydraulic switching valve decreases from the third pressure to the fourth pressure. The relationship between the current and the current (first relationship) may be obtained. That is, when the first mode 110a is set, the control device 110 controls the current from around the third current value corresponding to the preset third pressure to around the fourth current value corresponding to the fourth pressure. Change. The acquisition unit 112 acquires an output current value in the second switching range S2 until the detected pressure changes from the preset third pressure to the fourth pressure, and the detected pressure. In this case, the storage unit 113 stores the output current value and the detected pressure in the second switching range S2.

  In the above-described embodiment, the predetermined range when changing the hydraulic pressure switching valve from the first speed to the second speed is a range (first switching range S1) until the pressure changes from the first pressure to the second pressure. The scope is not limited to this. Further, the predetermined range when the hydraulic pressure switching valve is changed from the second speed to the first speed is a range from the third pressure to the fourth pressure (second switching range S2), but the predetermined range is not limited thereto. Not done. For example, in any case of increasing the speed from the first speed to the second speed and decelerating the speed from the second speed to the first speed, the range (use range) of the hydraulic oil applied to the hydraulic switching valve is set as a predetermined range. Is also good.

  The control unit 114 is operable in the second mode 110b and controls the operation valve 45. Specifically, an operation member 115 is connected to the control device 110. The operation member 115 is a member for instructing switching of the traveling speed of the work machine 1. The operation member 115 is constituted by, for example, a swingable seesaw switch, a slideable slide switch, or a pushable push switch. In a seesaw switch, the first speed can be set by swinging to one side, and the second speed can be set by swinging to the other side. In the slide switch, the first speed can be set by sliding to one side, and the second speed can be set by sliding to the other side. In the case of a push-type switch, the gear switches in the order of first speed and second speed each time the switch is pressed.

When the first speed or the second speed is set by the operation member 115, the control unit 114 operates based on the first relationship between the control signal (current) obtained by the obtaining unit 112 and the pressure (detected pressure) of the hydraulic oil. The control signal is output to the valve 45.
Specifically, in the second mode 110b, the control unit 114 sets the hydraulic switching valves (the first hydraulic switching valve 90A and the second hydraulic switching valve 90B) from the first speed to the second speed in response to the operation of the operation member 115. [When the traveling motors (first traveling motor 80A, second traveling motor 80B) are changed from the first speed to the second speed], the output current value corresponding to the first switching range S1 is referred to. The output current value indicated by the one switching range S1 is output to the operation valve 45. That is, the control unit 114 controls the operating valve 45 based on the relationship between the output current value and the detected pressure in the second switching range S2 stored in the storage unit 113.

  When changing the traveling motor from the second speed to the first speed in response to the operation of the operation member 115 in the second mode 110b, the control unit 114 refers to the output current value corresponding to the second switching range S2. Then, the output current value indicated by the second switching range S2 is output to the operation valve 45. That is, the control unit 114 controls the operating valve 45 based on the relationship between the output current value and the detected pressure in the second switching range S2 stored in the storage unit 113. The control unit 114 may control the operating valve 45 based on the first relationship as shown in FIG. 2 when maintaining the first speed and maintaining the second speed.

  For example, when the working machine 1 is manufactured, delivered, or maintained, the control device 110 is set to the setting mode (first mode) 110a, and the control signal output to the operating valve 45 and the operation detected by the first measuring device 120 are set. The first relationship with the oil pressure is acquired by the acquisition unit 112, and the acquired relationship is stored in the storage unit 113. After acquiring the first relationship between the control signal and the pressure of the hydraulic oil, in the control mode (second mode) 110b, if the control signal is output to the operating valve 45 based on the first relationship, the work implement 1 Variations in each case can be suppressed, and operability in traveling can be made constant. In particular, the traveling motor switches between the first speed and the second speed in accordance with the degree of opening of the operation valve 45, so that the operability when switching between the first speed and the second speed can be made constant.

  Further, when changing the traveling motor from the first speed to the second speed, the control device 110 controls the operating valve 45 based on the relationship between the control signal corresponding to the predetermined range and the pressure of the operating oil. Therefore, the operability when the traveling motor is increased from the first speed to the second speed can be improved. Further, when changing the traveling motor from the second speed to the first speed, the control device 110 controls the operating valve 45 based on the relationship between the control signal corresponding to the predetermined range and the pressure of the operating oil. Therefore, operability when the traveling motor is decelerated from the second speed to the first speed can be improved.

Also, by operating the operating valve 45 to change from the second speed to the second speed (when operating the operating valve 45 in one direction), the relationship between the control signal and the pressure is used. The relationship between the control signal and the pressure in the case of the first speed (when the operating valve 45 is operated in the other direction) is used. Therefore, even if the operating valve 45 has hysteresis, it is possible to appropriately control the pressure of the hydraulic switching valve and the like.
[Second embodiment]
FIG. 4 shows a hydraulic system according to the second embodiment. The hydraulic system of the traveling system shown in the second embodiment is applicable to the hydraulic system of the first embodiment described above. The description of the same configuration as that of the first embodiment is omitted. In the above-described embodiment, the first traveling hydraulic pump 66A and the second traveling hydraulic pump 66B operate the remote control valves 36, 37, 38, and 39, but in the second embodiment, the first traveling hydraulic pump 66A and the The second traveling hydraulic pump 66B is operated by an operating valve 46A and an operating valve 46B. The operation valve 46A and the operation valve 46B are electromagnetic proportional valves (proportional valves) whose opening degree is changed by a control signal. The swash plate of the first traveling hydraulic pump 66A changes based on the operation of the operating valve 46A. The swash plate of the second traveling hydraulic pump 66A changes based on the operation of the operating valve 46B. Note that the opening degrees of the operation valves 46A and 46B can be changed based on the operation of the operation member.

  The control device 130 is a device that controls the operation valve 46A and the operation valve 46B, and includes, for example, a CPU and the like. The control device 130 can be switched at least between the setting mode 130a and the control mode 130b. The setting mode 130a is a mode for performing various settings related to control. The control mode 130b is a mode for performing control. Switching between the setting mode 130a and the control mode 130b is performed by a switching device 111 connected to the control device 130.

  In the first mode 130a, a relationship between the rotation speed of the traveling hydraulic device 44 and a control signal output to the operating valve 46 (the operating valve 46A, the operating valve 46B) by the control device 130 is set. In this embodiment, the rotation speed of the traveling hydraulic device 44 is the rotation speed of the traveling motors (the first traveling motor 80A and the second traveling motor 80B). The rotation speed of the traveling hydraulic device 44 is detected by a second measuring device 140 that detects the rotation of the output shaft. Then, in the first mode 130a, the relationship between the rotation speed detected by the second measuring device 140 and the control signal output from the control device 130 to the operating valve 46, that is, the current (called the second relationship) is acquired. The relationship between the rotation speed of the traveling motor and the current is stored. In the control mode 130b, the operation valve 46 is controlled based on the second relationship.

Hereinafter, the setting mode and the control mode will be described together with the configuration of the control device 130.
The control device 130 includes an acquisition unit 132, a storage unit 133, and a control unit 134. The acquisition unit 132 and the control unit 134 are configured by programs and the like stored in the control device 130.
The acquisition unit 132 is operable when in the first mode 130a, and acquires a second relationship between a control signal (for example, current) and a rotation speed (detected rotation speed) detected by the second measuring device 140.

  When the first mode 130a is set by the switching device 111, the acquisition unit 132 acquires the second relationship between the control signal output to the operation valve 46 and the detected rotation speed. Specifically, when in the first mode 130a, the control device 130 changes the current (output current) output to the operation valve 46 from the minimum value to the maximum value. As illustrated in FIG. 5A, when the output current is changed from the minimum value to the maximum value, the obtaining unit 132 obtains a current value of a predetermined output current and a detected rotation speed. That is, the acquisition unit 132 determines whether the angle of the swash plate of the traveling hydraulic pump changes from the smallest angle (the output current is minimum) to the largest angle (the maximum output current) of the traveling hydraulic pump. A second relationship between the output current and the detected rotation speed is obtained. The storage unit 133 is operable in the first mode 130a, and stores the relationship (second relationship) between the output current acquired by the acquisition unit 132 and the detected rotation speed.

  Specifically, the acquisition unit 132 increases the rotation speed of the traveling motors (the first traveling motor 80A and the second traveling motor 80B) (when increasing the rotation speed of the traveling motor from a low speed to a high speed), As shown in (2), the second relationship between the output current and the detected rotation speed in a predetermined range between a low speed and a high speed may be obtained. The storage unit 133 stores the second relation as illustrated in FIG. 5B. The low speed indicates that the rotation speed of the traveling motor is small, and the high speed indicates that the rotation speed of the traveling motor is large. The range of the rotation speed corresponding to the low speed and the range of the rotation speed corresponding to the high speed are determined in advance. May be set. For example, low speed may be set to less than 1/2 of the maximum rotation speed of the traveling motor, and high speed may be set to 1/2 or more of the maximum rotation speed of the traveling motor. The numerical values and ranges of the low speed and the high speed are not limited to these.

In addition, when decreasing the rotation speed of the traveling motors (the first traveling motor 80A and the second traveling motor 80B) (when increasing the rotation speed of the traveling motor from a high speed to a low speed), the acquisition unit 132, as shown in FIG. 5C, Alternatively, the second relationship between the output current and the detected rotation speed in a predetermined range between high speed and low speed may be obtained. The storage unit 133 stores a second relationship as illustrated in FIG. 5C.
The control unit 134 is operable when in the second mode 130b, and controls the operation valve 46. Specifically, an operation member 150 is connected to the control device 130. The operation member 150 is a member that operates the operation valve 46. The operation member 150 is a swingable lever or the like.

When the operation member 150 is operated, the control unit 134 outputs a control signal to the operating valve 46 based on the second relationship between the control signal (current) obtained by the obtaining unit 132 and the detected rotation speed.
Specifically, in the second mode 130b, the control unit 134 outputs a control signal to the operation valve 46 in accordance with the operation amount of the operation member 150. When the operation member 150 is swung from the neutral position in one direction or the other direction, the control unit 134 increases the angle of the swash plate of the traveling motor. That is, when the operation member 150 is swung in one direction or the other direction from the neutral state, the control unit 134 determines that the rotation speed of the traveling motor is to be increased, and refers to the storage unit 133 to change from the low speed to the high speed. Is output to the operating valve 46.

  The control unit 134 outputs a control signal to the operating valve 46 according to the operation amount of the operation member 150 in the second mode 130b. When the operation member 150 is swung from the position in one direction or the position in the other direction toward the neutral position, the control unit 134 reduces the angle of the swash plate of the traveling motor. That is, when the control unit 134 swings the operation member 150 from the position in one direction or the position in the other direction toward the neutral position, the control unit 134 determines that the rotation speed of the traveling motor is to be reduced, and refers to the storage unit 133. Then, a control signal corresponding to a predetermined range from high speed to low speed is output to the operating valve 46.

  For example, at the time of manufacture, delivery, maintenance, etc. of the working machine 1, the control device 130 is set to the setting mode (first mode) 130 a, and the control signal output to the operating valve 46 and the travel detected by the second measurement device 140. The second relationship with the number of rotations of the motor is acquired by the acquiring unit 132, and the acquired relationship is stored in the storage unit 133. After obtaining the second relationship between the control signal and the rotation speed of the traveling motor, if the control signal is output to the operating valve 46 based on the second relationship in the control mode (second mode) 130b, the working machine It is possible to suppress the variation of each one, and it is possible to make the operability in traveling constant. In particular, in the traveling hydraulic pump, the angle of the swash plate changes according to the opening degree of the operation valve 46, so that the operability at the time of speed increase and deceleration can be made constant.

  When increasing the rotation speed of the traveling motor, the control device 130 controls the operation valve 46 based on a relationship between a control signal in a predetermined range from a low speed to a high speed and the rotation speed of the traveling motor. Therefore, operability when increasing the rotation speed of the traveling motor can be improved. When decreasing the rotation speed of the traveling motor, the control device 130 controls the operation valve 46 based on a relationship between a control signal in a predetermined range from a high speed to a low speed and a rotation speed of the traveling motor. . Therefore, it is possible to improve operability when reducing the rotation speed of the traveling motor.

The embodiments disclosed this time are to be considered in all respects as illustrative and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.
The above-described hydraulic switching valves (the first hydraulic switching valve 90A and the second hydraulic switching valve 90B) have the neutral position 90c. Instead, the hydraulic switching valve is a valve having no neutral position, that is, The valve may be switchable between the first position 90a and the second position 90b. In this case, the pressure (detection pressure) when the traveling motor is changed from the first speed to the second speed or from the second speed to the first speed is as shown in FIG.

  As shown in FIG. 7, the hydraulic system described above may include a braking device 160 that can switch between a braking state in which the traveling hydraulic device 44 is braked and a release state in which the braking state is released. The braking device 160 brakes the traveling motors (the first traveling motor 80A and the second traveling motor 80B). The braking device 160 includes a first disk provided on the output shaft of the first traveling motor 80A, a movable second disk, and a spring that biases the second disk toward the side that contacts the first disk. I have. In addition, the braking device 160 includes an accommodating portion (accommodating case) 160a that accommodates the first disk, the second disk, and the spring. In this storage section 160a, an oil path 161 is connected to a storage section in which the second disk is stored. The oil passage 106 is connected to the oil passage 161 so that hydraulic oil can be supplied to the storage section of the storage section 160a. An operating valve 162 that can be opened and closed is connected to the oil passage 161. The operation valve 162 is controlled by the control device 110. When the operating valve 162 is opened under the control of the control device 110, the operating oil is supplied to the storage section of the storage section 160a. When the pressure of the hydraulic oil in the storage section becomes equal to or higher than a predetermined value, the second disk moves to the opposite side to the braking (opposite to the biasing direction of the spring), and the braking by the braking device 160 can be released. On the other hand, when the operation valve 162 is closed under the control of the control device 110, the pressure of the pilot oil in the storage section of the storage section 160a decreases. When the pressure of the hydraulic oil in the storage section becomes equal to or lower than a predetermined value, the second disk moves to the side in contact with the first disk, and braking by the braking device 160 can be performed.

  When in the first mode 110a, the control device 110 closes the operation valve 162 and puts the braking device 160 into a braking state. Further, in the second mode 110b and when an operation member such as the travel lever 40 is operated, the control device 110 opens the operating valve 162 to release the braking state by the braking device 160. When the control device 110 is in the second mode 110b and the operation member such as the travel lever 40 has not been operated, the control valve 110 closes the operation valve 162 and performs braking by the braking device 160. Therefore, the relationship between the control signal and the pressure of the hydraulic oil can be acquired in a state where the work machine 1 is braked so as not to run. Although FIG. 7 illustrates the configuration of the first embodiment as an example, the configuration is applicable to the configuration of the second embodiment. That is, the operations of the braking device 160 and the control device described above are also applicable to the hydraulic system of the second embodiment.

  In the above-described embodiment, the cam motor (radial piston motor) is exemplified as the travel motor. However, the travel motor is not limited to the above-described motor, and any other piston motor other than the radial piston motor may be used. Is also good.

1 Working Machine 44 Traveling Hydraulic Device 45 Operating Valve 46 Operating Valve 80A First Traveling Motor 80B Second Traveling Motor 110 Controller 110a First Mode (Setting Mode)
110b 2nd mode (control mode)
111 Switching device 112 Acquisition unit 113 Storage unit 114 Control unit 120 First measuring device 130 Control device 130a First mode (setting mode)
130b 2nd mode (control mode)
132 acquisition unit 133 storage unit 134 control unit 140 second measurement device 160 braking device 162 operating valve

Claims (2)

A hydraulic pump that discharges hydraulic oil,
An operating valve capable of changing the hydraulic oil pressure,
A traveling hydraulic device whose operating state changes according to the operating oil of the operating valve;
A first measuring device capable of detecting a pressure of hydraulic oil acting on the traveling hydraulic device,
An acquiring unit capable of acquiring a relationship between the control signal and the pressure of the hydraulic oil detected by the first measuring device; a storage unit storing a relationship between the control signal acquired by the acquiring unit and the pressure of the hydraulic oil; A control device having a control unit that controls the operating valve based on the relationship stored in the storage unit,
A switching device capable of switching between a first mode in which the acquisition unit and the storage unit operate and a second mode in which the control unit operates,
With
A hydraulic system for a working machine including a braking device that can be switched between a braking state for braking the traveling hydraulic device and a release state for releasing the braking state, and that is in a braking state when in the first mode . A hydraulic pump that discharges hydraulic oil,
An operating valve capable of changing the hydraulic oil pressure,
A traveling hydraulic device whose operating state changes according to the operating oil of the operating valve;
A first measuring device capable of detecting a pressure of hydraulic oil acting on the traveling hydraulic device,
An acquiring unit capable of acquiring a relationship between the control signal and the pressure of the hydraulic oil detected by the first measuring device; a storage unit storing a relationship between the control signal acquired by the acquiring unit and the pressure of the hydraulic oil; A control device having a control unit that controls the operating valve based on the relationship stored in the storage unit,
A switching device capable of switching between a first mode in which the acquisition unit and the storage unit operate and a second mode in which the control unit operates,
With
The operating valve is a proportional valve capable of changing the pressure of the operating oil,
The traveling hydraulic device includes a hydraulic switching valve that switches to a first position, a second position, and an intermediate position in accordance with the degree of opening of the proportional valve, and switches to first speed when the hydraulic switching valve is at the first position. A traveling motor that switches to a second speed when the hydraulic pressure switching valve is in the second position ;
Has,
The first measuring device is configured such that, when increasing the travel motor from the first speed to the second speed, the hydraulic pressure switching valve switches from the intermediate position to the second position in a first switching range. A second switching when the hydraulic switching valve switches from the intermediate position to the first position when detecting the pressure acting on the hydraulic switching valve and decelerating the traveling motor from the second speed to the first speed. Detecting the pressure acting on the hydraulic switching valve in the range,
In the first mode, the acquisition unit is configured to: a pressure acting on the hydraulic pressure switching valve in the first switching range, a first control signal that is a control signal output to the proportional valve in the first switching range, and And a relationship between the pressure acting on the hydraulic switching valve in the second switching range and a second control signal that is a control signal output to the proportional valve in the second switching range is obtained. ,
In the second mode, the control unit controls the proportional valve based on the pressure in the first switching range and the first control signal, and controls the pressure in the second switching range, the second control signal, A hydraulic system for a working machine that controls the proportional valve based on the hydraulic pressure.

Images