JP6190297B2 - Operating device - Google Patents

Description

  The present invention relates to an operating device that outputs a hydraulic signal and an electrical signal.

  Conventionally, power machines such as hydraulic excavators, cranes, wheel loaders, bulldozers, etc. (in this specification and claims, these power machines (heavy machinery) are collectively referred to as “work machines”) Used for construction work. Generally, work machines are provided with a plurality of hydraulic actuators. For example, a hydraulic excavator, which is one of the work machines, has an upper revolving unit on the upper part of the lower traveling unit, and is connected to the upper revolving unit, an arm, an arm provided with an engine, a driver's seat, and a bucket at the tip A boom or the like is provided. The hydraulic excavator is provided with a plurality of hydraulic actuators such as a traveling motor, a turning motor, a boom cylinder, an arm cylinder, and a bucket cylinder, and a hydraulic pump that supplies pressure oil to these hydraulic actuators. Has been.

  FIG. 9 is a block diagram showing a schematic configuration of a drive control system 101 for a work vehicle according to Conventional Example 1. A drive control system 101 for a work vehicle according to Conventional Example 1 has, as a basic structure, a variable displacement hydraulic pump 8, a hydraulic actuator 10 driven by hydraulic oil sent from the hydraulic pump 8, and an operation to the hydraulic actuator 10. A control valve 6 for switching the oil flow and a controller 7 for controlling the discharge amount of the hydraulic pump 8 are provided. A pilot valve 3 is connected to a pilot port of the control valve 6 via a pilot pipe line 5. The pilot valve 3 is provided with an operation unit 2 for receiving an operation input to the hydraulic actuator 10. A pilot pressure corresponding to the operation amount of the operation unit 2 is supplied from the pilot valve 3 to the control valve 6. The pilot line 5 is provided with a pressure sensor 91 that detects a pilot pressure, and a pilot pressure operation amount detection signal is output from the pressure sensor 91 to the controller 7. The controller 7 controls the pump discharge capacity of the hydraulic pump 8 so as to obtain a discharge amount proportional to the operation amount of the operation unit 2 based on the pilot pressure operation amount detection signal.

  In the work vehicle drive control system 101 according to the conventional example 1, the pump discharge capacity of the hydraulic pump 8 is controlled based on the pilot pressure operation amount detection signal, but the hydraulic pump 8 is controlled based on the operation amount of the operation unit 2. A drive control system configured to control the pump discharge capacity is also known (for example, Patent Document 1). In the drive control system 102 for the work vehicle according to the second conventional example shown in FIG. 10, an operation amount detection sensor 41 (for example, a potentiometer or the like) that detects the operation amount of the operation unit 2 is provided in the pilot valve 3. 7, the pump discharge capacity of the hydraulic pump 8 is controlled based on the operation amount detection signal v output from the operation amount detection sensor 41.

JP 2000-46006 A

  FIG. 4 is a graph showing an example of input / output characteristics of the pilot valve 3. As shown in this graph, the pilot pressure p, which is an output value from the pilot valve 3, varies irregularly with an increase in the operation portion operation amount θ, which is an input value to the pilot valve 3. A range where the operation portion operation amount θ is smaller than a predetermined set value θmin is a dead zone (neutral zone), and in this dead zone, the pilot pressure p is constant regardless of increase or decrease of the operation amount. FIG. 5 is a graph showing an example of input / output characteristics of the operation amount detection sensor 41. As shown in this graph, the operation amount detection signal v that is an output value of the operation amount detection sensor 41 increases linearly with an increase in the operation portion operation amount θ that is an input value to the operation amount detection sensor 41. .

  When the input / output characteristics of the pilot valve 3 and the input / output characteristics of the manipulated variable detection sensor 41 are compared, the timing of the output values and the characteristics of the changes with respect to these input values are different. Therefore, as in the work machine drive control system 102 according to the conventional example 2, the hydraulic pump 8 and the control valve are based on signals (operation amount detection signal v and pilot pressure p) that are based on the same operation unit operation amount θ but have different characteristics. When 6 operates, the controller 7 performs processing for associating signals having different characteristics. Therefore, in order to cause the controller 7 to execute processing for making the manipulated variable detection signal v correspond to the pilot pressure p, it is necessary to change the program of the controller 7 and confirm the operation of the actual machine after changing the program. .

  Further, the pilot pressure p of the pilot valve 3 has an individual difference (manufacturing variation) with respect to the operation portion operation amount θ, and the operation amount detection signal v of the operation amount detection sensor 41 is also related to the operation portion operation amount θ. Since there is an individual difference (manufacturing variation), there is a problem that when these are associated, the variation is superimposed.

  In addition, when the work machine drive control system 101 according to the conventional example 1 is replaced with the work machine drive control system 102 according to the conventional example 2, the same complicated work as described above is required.

  The present invention has been made in view of the above circumstances, and is an operating device that outputs a hydraulic signal and an electrical signal corresponding to an operation amount of an operating unit, and an electrical signal output from the operating device is input. The object is to eliminate or simplify the processing in an apparatus (for example, a controller).

The operating device according to the present invention includes:
An operation unit;
A pilot valve that outputs a pilot pressure corresponding to an operation amount of the operation unit;
An electrical signal output device that outputs an operation amount signal corresponding to the operation amount of the operation unit,
The electrical signal output device detects an operation amount of the operation unit and outputs an operation amount detection signal corresponding to the operation amount; and the operation amount detection signal is output from the pilot valve. The operation amount signal calculating means for calculating the operation amount signal by converting it to have a correlation with the pilot pressure, and the operation amount signal output means for outputting the calculated operation amount signal.

  Here, the operation amount signal calculation means compares the operation amount detection signal with a predetermined value, and if the operation amount detection signal is equal to or less than the predetermined value, the operation unit is determined to be at a certain size as being located in the dead zone. The operation amount signal is calculated, and if the operation amount detection signal is greater than a predetermined value, the operation amount signal having a magnitude corresponding to the operation amount of the operation unit is preferably calculated. .

  According to the operating device having the above configuration, the operation amount signal (electric signal) output from the electric signal output device and the pilot pressure (hydraulic signal) output from the pilot valve have a positive correlation. When this operating device is applied to a drive control system for a hydraulic actuator provided in a work machine, the characteristics of the pilot pressure output to the control valve with respect to the operating amount of the operating portion and the controller for the operating amount of the operating portion are output. The characteristics of the manipulated variable signal correspond (match). Therefore, processing for associating the operation amount signal with the pilot pressure is not required in a device (for example, a controller) to which the operation amount signal is input, and the processing of this device can be simplified.

  In the operation device, the operation amount signal calculating means stores an operation amount detection signal-operation amount signal correspondence information indicating the operation amount signal corresponding to the operation amount detection signal. The operation amount signal may be calculated using the operation amount signal correspondence information.

  According to the above configuration, the operation amount signal can be calculated from the operation amount detection signal without performing a complicated operation.

  In the operation device, it is preferable that the operation amount detection signal-operation amount signal correspondence information is created by experimentally obtaining the operation amount signal corresponding to the operation amount detection signal.

  According to the above configuration, regardless of the individual difference (variation) that occurs in the pilot pressure output from the pilot valve and the magnitude of the detection error between the operation unit and the operation amount detection sensor that occurs in the operation amount detection signal, An operation amount signal in which an individual difference or a detection error between the operation unit and the operation amount detection sensor is corrected can be calculated.

  According to the present invention, the pilot pressure output from the operating device and the operation amount signal output from the operating device have a positive correlation. Therefore, in the device to which the operation amount signal from the operation device is input, the processing for associating the pilot pressure with the operation amount signal can be made unnecessary or simplified.

It is the block diagram which showed schematic structure of the drive control system of the working machine provided with the operating device which concerns on one Embodiment of this invention. It is the block diagram which showed the flow of the electrical signal of an electrical signal output device. It is a figure which shows an example of the operation amount detection signal-operation amount signal correspondence information. 3 is a graph showing input / output characteristics of a pilot valve. 5 is a graph showing input / output characteristics of an operation amount detection sensor. 5 is a graph showing a relationship between an operation amount detection signal and an operation amount signal. It is the graph which showed the input-output characteristic of the electric signal output device. It is the graph which showed the relationship between the operation amount signal and pilot pressure. It is a block diagram which shows schematic structure of the drive control apparatus of the working vehicle which concerns on the prior art example 1. FIG. It is a block diagram which shows schematic structure of the drive control apparatus of the working vehicle which concerns on the prior art example 2.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a schematic configuration of a drive control system 1 for a work machine including an operating device 100 according to an embodiment of the present invention. As shown in FIG. 1, an operating device 100 according to an embodiment of the present invention is used as a component of a drive control system 1 for a work machine. As a basic structure, the drive control system 1 for a work machine switches a variable displacement hydraulic pump 8, a hydraulic actuator 10 driven by hydraulic oil sent from the hydraulic pump 8, and a flow of hydraulic oil to the hydraulic actuator 10. A control valve 6 and a controller 7 for controlling the discharge amount of the hydraulic pump 8 are provided. The hydraulic actuator 10 is, for example, a hydraulic cylinder or a hydraulic motor provided in the work machine. Here, in order to simplify the description, the drive control system 1 includes one hydraulic actuator 10 and one hydraulic pump 8, but the drive control system 1 includes at least one hydraulic actuator 10 and at least one hydraulic pump. 8 may be provided.

  The hydraulic pump 8 is provided with a pump capacity control device 81 that controls the pump discharge flow rate of the hydraulic pump 8. The pump capacity control device 81 can be composed of, for example, a regulator connected to the swash plate of the hydraulic pump 8 and an electromagnetic proportional valve that regulates the driving pressure of the regulator. The pump capacity control device 81 controls the pump discharge flow rate by changing the swash plate angle of the hydraulic pump 8. The operation of the pump displacement control device 81 is controlled by a tilt control signal from the controller 7.

  The control valve 6 is provided in a hydraulic circuit 11 for supplying hydraulic oil from the hydraulic pump 8 to the hydraulic actuator 10. The control valve 6 is a direction switching valve that switches a flow direction of the hydraulic oil supplied to the hydraulic actuator 10 and a start / stop of the supply of the hydraulic oil. The operation direction and start / stop of the hydraulic actuator 10 are switched by the operation of the control valve 6. A pilot pressure is supplied from the operating device 100 to the pilot port of the control valve 6 through the pilot line 5, and the operation of the control valve 6 is controlled by this pilot pressure.

  The operation device 100 includes an operation unit 2, a pilot valve 3 that outputs a pilot pressure (hydraulic signal) corresponding to the operation amount of the operation unit 2, and an operation amount signal (electric signal) corresponding to the operation amount of the operation unit 2. And an electric signal output device 4 for outputting.

  The operation unit 2 is an operation input unit that receives an operation command input to the hydraulic actuator 10. The operation of the hydraulic actuator 10 is determined by the operation amount of the operation unit 2 (the direction in which the operation unit 2 tilts, the angle, the speed, and the like).

  The pilot valve 3 is a hydraulic signal output unit that outputs a hydraulic signal corresponding to the operation amount of the operation unit 2 to the control valve 6. The pilot valve 3 is provided with a hydraulic circuit (not shown). When the operation unit 2 is operated, a pilot pressure corresponding to the operation amount of the operation unit 2 is output to the pilot pipe line 5.

  The electric signal output device 4 is an electric signal output unit that outputs an electric signal corresponding to the operation amount of the operation unit 2 to the controller 7. FIG. 2 is a block diagram showing the flow of electrical signals of the electrical signal output device 4. As shown in FIG. 2, the electrical signal output device 4 includes an operation amount detection sensor 41, an operation amount signal calculation means 42, and an operation amount signal output means 43. The operation amount detection sensor 41 and the operation amount signal calculation means 42, the operation amount signal calculation means 42 and the operation amount signal output means 43, and the operation amount signal output means 43 and the controller 7 are connected to each other by wire or wireless so that an electric signal can be transmitted. Has been.

  The operation amount detection sensor 41 is an operation amount detection unit that directly or indirectly detects an operation amount (for example, a tilt angle) of the operation unit 2. The operation unit 2 can be configured by, for example, at least one potentiometer that detects the tilt angle of the operation unit 2. The operation amount detection sensor 41 detects the operation portion operation amount θ and outputs an operation amount detection signal v corresponding to the operation portion operation amount θ to the operation amount signal calculation means 42. The manipulated variable detection signal v may be either a voltage value or a current value.

  The operation amount signal calculation means 42 acquires the operation amount detection signal v from the operation amount detection sensor 41 and calculates the operation amount signal v ′ based on the acquired operation amount detection signal v. The operation amount signal output means 43 outputs the calculated operation amount signal v ′ to the controller 7. The controller 7 that has acquired the operation amount signal v ′ is based on the received operation amount signal v ′ so that the discharge direction and the discharge amount of the hydraulic oil of the hydraulic pump 8 are changed according to the operation amount of the operation unit 2. The tilt control signal is calculated, and this tilt control signal is output to the pump displacement control device 81.

  In the present embodiment, the operation amount signal calculation means 42 and the operation amount signal output means 43 are integrally configured. The operation amount signal calculation means 42 (and the operation amount signal output means 43) provide a CPU (Central Processing Unit), a ROM (Read Only Memory) in which a program is stored, and a temporary storage area for CPU work as a basic configuration. A random access memory (RAM), a timer, and an input / output port (I / O) for inputting / outputting input / output data. The operation amount signal calculating means 42 (and the operation amount signal output means 43) calculates and outputs the operation amount signal v ′ by the cooperation of software such as a program stored in the ROM and hardware such as a CPU. To do. As the operation amount signal calculation means 42 (and the operation amount signal output means 43), for example, a microcontroller can be used.

  In the operation amount signal calculating means 42, for example, operation amount detection signal-operation amount signal correspondence information as shown in FIG. 3 is stored. The operation amount detection signal-operation amount signal correspondence information is information for uniquely deriving the operation amount signal v ′ corresponding to the operation amount detection signal v. When the operation amount signal calculating means 42 receives the operation amount detection signal v from the electrical signal output device 4, the operation amount signal calculating means 42 calculates the operation amount signal v ′ with reference to the operation amount detection signal-operation amount signal correspondence information. As described above, by using the operation amount detection signal-operation amount signal correspondence information, the operation amount signal v ′ can be uniquely obtained based on the operation amount detection signal v without requiring a complicated calculation.

  The operation amount detection signal-operation amount signal correspondence information is the operation amount corresponding to the operation amount detection signal v in the operation device 100 on which the electric signal output device 4 storing the operation amount detection signal-operation amount signal correspondence information is mounted. It is desirable that the signal v ′ is created by experimentally obtaining it. The pilot pressure p output from the pilot valve 3 has individual differences due to manufacturing variations of components, and the operation amount detection signal v output from the operation amount detection sensor 41 is between the operation unit 2 and the operation amount detection sensor 41. Detection error (individual difference). Therefore, if the operation amount signal v ′ is calculated using the operation amount detection signal−operation amount signal correspondence information obtained experimentally as described above, the calculated operation amount signal v ′ is calculated by the individual difference of the pilot pressure p, The detection error between the operation unit 2 and the operation amount detection sensor 41 is corrected. Therefore, it is not necessary to correct the individual difference of the pilot pressure p or the detection error between the operation unit 2 and the operation amount detection sensor 41 by the controller 7 that is the output destination of the operation amount signal v ′.

  Note that the operation amount detection signal-operation amount signal correspondence information shown in FIG. 3 is the operation amount detection signal used by the operation amount signal calculation means 42 to calculate the operation amount signal v ′ from the operation amount detection signal v. It is an aspect of the operation amount signal correspondence information. The operation amount detection signal-operation amount signal correspondence information is not limited to the table, and may be an arithmetic expression, a graph, a map, or the like. Further, the operation amount detection signal-operation amount signal correspondence information may be a filter applied to the operation amount detection signal v.

  FIG. 4 is a graph showing an example of input / output characteristics of the pilot valve 3. The horizontal axis of this graph represents the operation portion operation amount θ that is an input value to the pilot valve 3, and the vertical axis represents the pilot pressure p that is the output value of the pilot valve 3. The input / output characteristics of the pilot valve 3 are irregular and nonlinear. The pilot valve 3 is provided with a dead zone in which the pilot pressure p does not change regardless of changes in the operation amount. In the present embodiment, the dead zone is set in a range where the operation portion operation amount θ is equal to or less than a predetermined first set value θmin. In the range where the operation portion operation amount θ is larger than the first setting value θmin and smaller than the predetermined second setting value θmax, the pilot pressure p corresponds substantially linearly to the operation portion operation amount θ.

  FIG. 5 is a graph showing an example of input / output characteristics of the operation amount detection sensor 41. The horizontal axis of this graph represents the operation unit operation amount θ that is an input value to the operation amount detection sensor 41, and the vertical axis represents the operation amount detection signal v that is an output value of the operation amount detection sensor 41. The operation amount detection signal v is expressed as a linear function of the operation unit operation amount θ that increases as the operation unit operation amount θ increases regardless of whether or not the operation unit operation amount θ is in the dead zone.

  As described above, the input / output characteristics of the pilot valve 3 and the input / output characteristics of the operation amount detection sensor 41 are different. Therefore, the operation amount signal calculation means 42 calculates the operation amount signal v ′ by converting the operation amount detection signal v so as to have a positive correlation with the pilot pressure p output from the pilot valve 3. As a result, the relationship between the operation amount detection signal v and the operation amount signal v 'has a positive correlation as shown in FIG. More specifically, the operation amount signal calculation means 42 compares the operation amount detection signal v with a predetermined value corresponding to the first set value θmin, and if the operation amount detection signal v is equal to or less than the predetermined value, the operation unit An operation amount signal v ′ having a certain magnitude is calculated assuming that 2 is located in the dead zone. Further, if the operation amount detection signal v is larger than the predetermined value, the operation amount signal calculation means 42 calculates an operation amount signal v ′ having a magnitude corresponding to the operation amount of the operation unit 2. The operation amount signal v ′ calculated in this way is output from the electric signal output device 4, whereby the input / output characteristics of the pilot valve 3 and the input / output characteristics of the electric signal output device 4 correspond (match).

  FIG. 7 is a graph showing an example of input / output characteristics of the electrical signal output device 4. The horizontal axis of this graph represents the operation portion operation amount θ that is an input value to the electric signal output device 4, and the vertical axis represents the operation amount signal v ′ that is an output value of the electric signal output device 4. In the input / output characteristics of the electrical signal output device 4, when the operation portion operation amount θ is within the dead zone range, the operation amount signal v ′ is a constant value (zero) representing neutrality regardless of the operation portion operation amount θ. When the operation unit operation amount θ is outside the dead zone range, the operation amount signal v ′ is a signal having a magnitude corresponding to the operation unit operation amount θ. Here, the operation amount signal v ′ increases as the operation unit operation amount θ increases.

  FIG. 8 is a graph showing an example of the relationship between the manipulated variable signal v ′ and the pilot pressure p. In this graph, the horizontal axis represents the pilot pressure p, and the vertical axis represents the manipulated variable signal v '. As described above, since the input / output characteristics of the electrical signal output device 4 and the input / output characteristics of the pilot valve 3 correspond to the timing and characteristics of the change of the output value relative to the input value, the manipulated variable signal v ′ and the pilot There is a linearly corresponding correlation with the pressure p. That is, the manipulated variable signal v ′ can be expressed as a linear function of the pilot pressure p.

  As described above, in the work machine drive control system 1 according to the present embodiment, the operation amount signal v ′ that is an electric signal input to the controller 7 and the pilot pressure p that is a hydraulic signal input to the control valve 6. Have a highly accurate correlation, the input / output characteristics of the electrical signal output device 4 and the input / output characteristics of the pilot valve 3 correspond to each other with high precision. Therefore, the controller 7 does not require processing for associating the operation amount detection signal v with the pilot pressure p. Thus, the program for causing the controller 7 to execute processing for making the operation amount detection signal v correspond to the pilot pressure p, and the input / output characteristics of at least one of the operation amount detection sensor 41 and the pilot valve 3 change. It is not necessary to change the program and confirm the operation of the actual machine after changing the program.

  Further, if the operation amount detection signal-operation amount signal correspondence information used when calculating the operation amount signal v ′ is obtained at the time of manufacturing the operation device of the present invention or experimentally, the operation amount signal In v ′, manufacturing variations (individual differences) of the pilot valve 3 and detection errors of the operation amount detection sensor 41 are corrected. Therefore, it is not necessary for the controller 7 to correct the individual difference of the pilot valve 3 or the detection error of the operation amount detection sensor 41 in the operation amount signal v ′.

  Further, in the drive control system 101 of the work machine that controls the pump discharge capacity of the hydraulic pump 8 by using the hydraulic signal as in the conventional example 1, the program installed in the controller 7 can be driven without significant change. The pilot valve 3 and the pressure sensor 91 of the control system 101 can be replaced with the operating device 100 according to this embodiment.

DESCRIPTION OF SYMBOLS 1 Drive control system 2 Operation part 3 Pilot valve 4 Electric signal output device 41 Operation amount detection sensor (operation amount detection means)
42 Operation amount signal calculation means 43 Operation amount signal output means 5 Pilot pipe 6 Control valve 7 Controller 8 Hydraulic pump 81 Pump capacity control device 10 Hydraulic actuator 100 Operation device

Claims (4)

An operation unit;
A pilot valve that outputs a pilot pressure corresponding to an operation amount of the operation unit;
An electrical signal output device that outputs an operation amount signal corresponding to the operation amount of the operation unit,
The electrical signal output device detects an operation amount of the operation unit and outputs an operation amount detection signal corresponding to the operation amount; and the operation amount detection signal is output from the pilot valve. A manipulated variable signal calculating means for calculating the manipulated variable signal by converting it to have a correlation with a pilot pressure; and an manipulated variable signal output means for outputting the calculated manipulated variable signal.
Operating device.   The operation amount signal calculating means compares the operation amount detection signal with a predetermined value, and if the operation amount detection signal is equal to or less than the predetermined value, the operation unit is located in a dead zone and has a certain size. The operation amount signal is calculated, and if the operation amount detection signal is larger than a predetermined value, the operation amount signal having a magnitude corresponding to the operation amount of the operation unit is calculated. Operating device.   The operation amount signal calculation means stores an operation amount detection signal-operation amount signal correspondence information indicating the operation amount signal corresponding to the operation amount detection signal, and this operation amount detection signal-operation amount signal correspondence information. The operating device according to claim 1, wherein the operating device is configured to calculate the operation amount signal using a computer.   The operation device according to claim 3, wherein the operation amount detection signal-operation amount signal correspondence information is created by experimentally obtaining the operation amount signal corresponding to the operation amount detection signal.

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