JP6904648B2 - Automatic oil introduction program, electronic equipment, oil introduction device, steering device and traveling vehicle - Google Patents

Description

The present invention relates to an automatic oil introduction program, an electronic device, an oil introduction device, a steering device, and a traveling vehicle.

A steering handle, a control device that outputs a drive signal based on the steering angle of the steering handle, and a drive signal output from the control device from the first port or the second port to the first pipe line or the second pipe line. A double-rotation hydraulic pump that discharges oil, a steering cylinder in which oil discharged from the double-rotary hydraulic pump is supplied via a first pipe or a second pipe and expands and contracts in the first or second direction, and oil. A by-wire type forklift equipped with a tank for storing a pump is known (for example, Patent Document 1).
Here, the double-rotation hydraulic pump, the steering cylinder, and the tank are the main elements constituting the steering hydraulic circuit. When introducing oil into the steering hydraulic circuit during forklift assembly or maintenance, the operator operates the steering handle while supplying oil to the forklift tank from an external tank separate from the forklift. This is to avoid responsiveness and the like when air bubbles are mixed in the steering hydraulic circuit.

Japanese Unexamined Patent Publication No. 2017-461

Although the operator operates the steering wheel according to a manual or the like, there is a possibility that air bubbles may remain in the steering hydraulic circuit due to individual differences.

The automatic oil introduction program according to the first aspect of the present invention is a steering cylinder in the automatic oil introduction program for causing a computer to execute oil when introducing oil from an external oil supply source into a steering hydraulic circuit mounted on a traveling vehicle. The first operation procedure of repeatedly expanding and contracting in both directions at the first speed, and after the first operation procedure, the second operation procedure of repeatedly expanding and contracting the steering cylinder in both directions at a second speed faster than the first speed are sequentially performed. A computer is made to execute the first and second operation procedures by rotating both rotary hydraulic pumps in the forward and reverse directions .
The electronic device according to the second aspect of the present invention implements the oil automatic introduction program according to the first aspect, and causes the computer of the traveling vehicle to execute the first and second operation procedures. Has an interface to connect.
The oil introduction device according to the third aspect of the present invention is an oil introduction device that introduces oil from an external oil supply source into a steering hydraulic circuit mounted on a traveling vehicle based on an oil introduction command. The first expansion and contraction control unit that repeatedly expands and contracts in both directions at the time and the first speed, and the steering cylinder repeatedly expands and contracts in both directions at a second speed faster than the first speed until the second time elapses after the lapse of the first time. A second expansion / contraction control unit is provided, and the first expansion / contraction control unit repeatedly reverses forward / reverse rotation of a double-rotation hydraulic pump that supplies oil to the steering cylinder at the first rotation speed for the first hour, and the second expansion / contraction control unit is provided. The expansion / contraction control unit repeatedly reverses the forward rotation of the double-rotation hydraulic pump for a second time at a second rotation speed higher than the first rotation speed .
The steering device according to the fourth aspect of the present invention is a birotary hydraulic pump that discharges oil from the steering handle and the first or second discharge port to the first or second pipeline based on the operation of the steering handle. A control unit that outputs a drive signal for driving the birotary hydraulic pump based on the operation of the steering handle, and oil discharged from the birotary hydraulic pump is supplied via the first or second pipeline. A steering cylinder that expands and contracts in the first or second direction and a tank in which the oil is stored are provided, and the control unit elapses the first time when an oil introduction command is input to the control unit. Until the first rotation speed, the double rotation hydraulic pump is repeatedly rotated forward and reverse, and after the first time elapses, until the second time elapses, both of the two rotation speeds are higher than the first rotation speed. The rotary hydraulic pump is repeatedly rotated forward and reverse.
The traveling vehicle according to the fifth aspect of the present invention has a steering device according to the fourth aspect and a traveling driving device that applies a traveling driving force to the tires steered by the steering device.

According to the present invention, since the steering cylinder is repeatedly expanded and contracted in a predetermined operation without depending on individual differences of the operator, it is possible to suppress the residual air bubbles when introducing oil into the steering hydraulic circuit. can. In addition, the man-hours required for the oil introduction work of the worker can be omitted.

The schematic block diagram which shows an example of the steering apparatus mounted on the forklift of an embodiment. The hydraulic circuit diagram which shows an example of the steering hydraulic circuit which concerns on embodiment. The block diagram which shows an example of a part of the control system used in the forklift which concerns on embodiment. The flowchart explaining the oil automatic introduction process executed by the forklift which concerns on embodiment. The block diagram which shows an example of the electronic device which implemented the oil automatic introduction program which concerns on modification 1.

The forklift of the embodiment implements a hydraulic circuit including a steering cylinder that controls the discharge oil of the birotary hydraulic pump based on the operation amount of the steering handle and is expanded and contracted to the left and right by the discharge oil to steer the tire. The oil supplied to the steering cylinder is controlled by the steering hydraulic circuit to control the operation of the steering cylinder.

When assembling a forklift, it is necessary to introduce oil into the steering hydraulic circuit. The forklift of the embodiment is equipped with a function of automatically introducing oil into the steering hydraulic circuit (hereinafter, referred to as an oil automatic introduction function). Hereinafter, the forklift of the embodiment will be described with reference to FIGS. 1 to 4.

FIG. 1 is a schematic configuration diagram showing an example of a steering device mounted on the forklift of the embodiment. As shown in FIG. 1, the forklift includes a steering device 10. The steering device 10 includes a steering handle (steering wheel) 11 for steering, a steering angle sensor 12, an electromagnetic brake 13, a PS controller 20, an electric motor 30, a motor encoder 31, and a birotary hydraulic pump 40. And a steering cylinder 50 and a tire angle sensor 51. The forklift also includes a vehicle control module (hereinafter, VCM) 21 that controls the entire vehicle, which will be described later with reference to FIG.

The steering angle sensor 12 is, for example, a non-contact type sensor, generates a signal (steering angle signal) corresponding to the steering angle of the steering handle 11, and outputs the steering angle signal to the PS controller 20. The electromagnetic brake 13 is controlled by the PS controller 20 and applies a steering reaction force to the steering handle 11. The electromagnetic brake 13 applies a steering reaction force to the steering handle 11 according to the steering angle of the steering handle 11.

The electric motor 30 is electrically connected to the PS controller 20 and mechanically connected to the birotary hydraulic pump 40. The rotation direction and rotation speed of the electric motor 30 are controlled by the PS controller 20 to drive the double-rotation hydraulic pump 40. The motor encoder 31 generates a signal (rotation speed signal) corresponding to the rotation speed of the electric motor 30, and outputs the rotation speed signal to the PS controller 20.

The birotary hydraulic pump 40 is driven by an electric motor 30 and rotates in a forward rotation direction or a reverse rotation direction. The birotary hydraulic pump 40 has a first port 41a and a second port 41b, and discharges oil from the first or second ports 41a and 41b to the first pipe line 42a or the second pipe line 42b. The oil discharged from the birotary hydraulic pump 40 is supplied to the steering cylinder 50.

The steering cylinder 50 is a hydraulic cylinder for steering, and oil discharged from the double-rotation hydraulic pump 40 is supplied via the first or second pipelines 42a and 42b, and is supplied in the first or second direction (in the figure). Expands and contracts in the left-right direction of. By expanding and contracting the steering cylinder 50, the tire 60 connected to the steering cylinder 50 is steered. The tire angle sensor 51 generates a signal (tire angle signal) corresponding to the steering angle of the tire 60, and outputs the tire angle signal to the PS controller 20.

The PS controller 20 is composed of a processor such as a CPU or FPGA, a memory such as a ROM or RAM, and other peripheral circuits, and controls the steering of the forklift based on a control program.

The PS controller 20 calculates the steering angle of the steering handle 11 by using the steering angle signal from the steering angle sensor 12. The PS controller 20 controls the electromagnetic brake 13 based on the calculated steering angle of the steering handle 11, and causes the electromagnetic brake 13 to generate a steering reaction force according to the steering angle of the steering handle 11.

The PS controller 20 determines the target rotation speed of the electric motor 30 based on the calculated steering angle of the steering handle 11. The PS controller 20 generates a drive signal according to the target rotation speed, and outputs the drive signal to the pump inverter 32 (see FIG. 3) connected to the electric motor 30. The PS controller 20 controls the rotation direction and rotation speed of the electric motor 30 by outputting a drive signal to the pump inverter 32. The pump inverter 32 will be described later with reference to FIG.

The PS controller 20 controls the flow rate and direction of the oil discharged from the birotary hydraulic pump 40 by controlling the operation of the electric motor 30. By controlling the oil discharged from the double-rotation hydraulic pump 40 by the PS controller 20, the expansion and contraction operation of the steering cylinder 50 is controlled.

The PS controller 20 calculates the rotation speed of the electric motor 30 by using the rotation speed signal from the motor encoder 31. Further, the PS controller 20 calculates the steering angle of the tire 60 by using the tire angle signal from the tire angle sensor 51. The PS controller 20 corrects the drive signal for controlling the electric motor 30 based on the rotation speed of the electric motor 30 and the steering angle of the tire 60. That is, the PS controller 20 constantly detects the rotation speed of the electric motor 30 and the steering angle of the tire 60 by using the signals from each sensor, and feedback-controls the rotation speed of the electric motor 30. More specifically, the PS controller 20 corrects the target rotation speed of the electric motor 30 using the steering angle of the tire 60, and outputs a drive signal corresponding to the corrected target rotation speed to the pump inverter 32. By changing the drive signal input to the pump inverter 32, the rotation speed of the electric motor 30 is changed. As a result, the amount of expansion and contraction of the steering cylinder 50 is adjusted, and the steering angle of the tire 60 is adjusted.

When introducing oil into the hydraulic circuit during assembly or maintenance of a forklift, it is necessary to fill the hydraulic circuit with oil and bleed air so that air does not remain in the hydraulic circuit. The residual air in the hydraulic circuit causes problems such as a decrease in the responsiveness of the forklift. Conventionally, a worker operates a steering handle while supplying oil to a forklift tank from an external tank provided in a maintenance shop or the like. Although the operator operates the steering wheel according to a manual or the like, there are problems that air bubbles are mixed in the hydraulic circuit due to individual differences and that the work takes time.

Therefore, the PS controller 20 of the embodiment is equipped with an application (hereinafter referred to as an automatic oil introduction program) for executing a process for realizing the automatic oil introduction function. When an operation for executing the oil automatic introduction program is performed by the operator, the VCM 21 (see FIG. 3) issues an oil introduction command to the PS controller 20. The PS controller 20 drives the electric motor 30 according to the procedure of the oil automatic introduction program. That is, the PS controller 20 automatically controls the electric motor 30, which was conventionally manually operated by the operator at the time of refueling. As a result, oil is automatically circulated in the hydraulic circuit to bleed air in the hydraulic circuit. The operator can refuel and bleed air with a simple operation. The automatic refueling and air bleeding using the automatic oil introduction program will be described later with reference to FIG.

FIG. 2 is a hydraulic circuit diagram showing an example of the steering hydraulic circuit of the embodiment. The steering hydraulic circuit includes a double-rotation hydraulic pump 40, a steering cylinder 50, a tank (reservoir tank) 43 for storing oil, a first check valve 44a, a second check valve 44b, and a first relief valve 45a. And a second relief valve 45b. The external tank 100 shown in FIG. 2 is a tank provided in a maintenance shop or the like, and is connected to the tank 43 of the forklift during assembly or maintenance.

As described above, the birotary hydraulic pump 40 has first and second ports 41a and 41b, and is rotationally driven by the electric motor 30 to discharge oil to the first pipe line 42a or the second pipe line 42b. By changing the rotation direction of the double-rotation hydraulic pump 40, the first port 41a or the second port 41b discharges oil to the first or second pipelines 42a and 42b as an oil discharge port or an oil suction port. vinegar. Further, the amount of oil discharged from the double-rotation hydraulic pump 40 increases or decreases as the rotation speed of the electric motor 30 increases or decreases.

The steering cylinder 50 has a cylinder tube 51, a piston rod 52, and a piston 53 provided at the center of the piston rod 52. A first oil chamber 54 and a second oil chamber 55 partitioned by a piston 53 are provided in the cylinder tube 51. The first oil chamber 54 and the second oil chamber 55 are connected to the first port 41a and the second port 41b of the birotary hydraulic pump 40 via the first pipe line 42a and the second pipe line 42b, respectively. When the tire 60 is steered, the oil pressure from the birotary hydraulic pump 40 is supplied to the first oil chamber 54 and the second oil chamber 55, so that the piston 53 receives the oil pressure and moves the piston rod 52 in the left-right direction (piston). It is moved in the axial direction of the rod 52).

One end of the first check valve 44a is connected to the first pipeline 42a, and the other end is connected to the tank 43. The first check valve 44a prevents oil from flowing back from the first pipeline 42a into the tank 43. When the oil pressure of the first pipe line 42a is low, that is, when the first port 41a becomes a suction port, the first check valve 44a is opened and the oil of the tank 43 is supplied to the first pipe line 42a.

One end of the second check valve 44b is connected to the second pipeline 42b, and the other end is connected to the tank 43. The second check valve 44b prevents oil from flowing back from the second pipeline 42b to the tank 43. When the oil pressure of the second pipe line 42b is low, that is, when the second port 41b becomes a suction port, the second check valve 44b is opened and the oil of the tank 43 is supplied to the second pipe line 42b.

One end of the first relief valve 45a is connected to the first pipeline 42a, and the other end is connected to the tank 43. When the oil pressure of the first pipe line 42a is higher than the predetermined value, the first relief valve 45a releases (discharges) the oil of the first pipe line 42a to the tank 43, and the oil pressure of the first pipe line 42a is a predetermined value. Prevent it from becoming more than that.

One end of the second relief valve 45b is connected to the second pipeline 42b, and the other end is connected to the tank 43. In the second relief valve 45b, when the oil pressure of the second pipe line 42b is higher than the predetermined value, the oil of the second pipe line 42b is released to the tank 43, and the oil pressure of the second pipe line 42b becomes equal to or higher than the predetermined value. prevent. Since the first and second relief valves 45a and the second relief valve 45b limit the hydraulic pressure of the first and second pipelines 42a and 42b, it is possible to prevent an excessive load from being applied to each part of the steering hydraulic circuit.

The steering handle 11 (see FIG. 1) is rotated clockwise, and for example, as the electric motor 30 is driven in the forward direction in response to a drive signal from the PS controller 20, the double-rotation hydraulic pump 40 is also driven in the forward direction. Will be done. When the double-rotation hydraulic pump 40 is driven in the forward rotation, for example, oil is discharged from the first port 41a of the double-rotation hydraulic pump 40, and the oil is discharged into the first oil chamber 54 of the steering cylinder 50 through the first pipeline 42a. Is supplied.

When the oil pressure in the first oil chamber 54 rises, the piston 53 moves toward the second oil chamber 55. As a result, the piston rod 52 moves to the right, that is, the steering cylinder 50 extends to the right. Further, as the piston 53 moves to the second oil chamber 55 side, oil is discharged from the second oil chamber 55. The oil discharged from the second oil chamber 55 is sucked into the second port 41b of the birotary hydraulic pump 40 through the second pipeline 42b. As the piston rod 52 moves to the right, the tire 60 is steered to the right.

When the steering handle 11 is rotated counterclockwise, for example, as the electric motor 30 is driven in the reverse direction, the double-rotation hydraulic pump 40 is also driven in the reverse direction. When the birotary hydraulic pump 40 is reversely driven, for example, oil is discharged from the second port 41b of the birotary hydraulic pump 40, and oil is discharged into the second oil chamber 55 of the steering cylinder 50 through the second pipeline 42b. Is supplied. When the oil pressure in the second oil chamber 55 rises, the piston 53 moves toward the first oil chamber 54, the piston rod 52 moves to the left, that is, the steering cylinder 50 extends to the left. Further, as the piston 53 moves to the first oil chamber 54 side, oil is discharged from the first oil chamber 54 and is sucked into the first port 41a through the first pipeline 42a. As the piston rod 52 moves to the left, the tire 60 is steered to the left.

As described above, the steering angle of the steering handle 11, the number of revolutions of the electric motor 30, and the steering angle of the tire 60 are constantly detected by the PS controller 20, and the electric motor 30, the birotary hydraulic pump 40, and the steering cylinder 50 are constantly detected. Is feedback controlled by the PS controller 20.

FIG. 3 is a block diagram showing an example of a part of the control system used in the forklift of the embodiment. The forklift includes a VCM 21, a PS controller 20, an electric motor 30 for driving a double-rotation hydraulic pump 40, a pump inverter 32 for driving and controlling the electric motor 30, a display panel 70, a traveling drive device 80, and traveling. It is equipped with an inverter 81. Each of these devices and elements is connected to each other according to a communication method such as CAN (Controller Area Network) to perform data communication. Further, the forklift includes a steering angle sensor 12 and a tire angle sensor 51. The steering angle sensor 12 and the tire angle sensor 51 are each connected to the PS controller 20.

The VCM 21 is composed of a processor such as a CPU or FPGA, a memory such as a ROM or RAM, and other peripheral circuits, and controls the entire forklift based on a control program. The pump inverter 32 is composed of a plurality of switching elements and the like, and controls the switching elements on and off based on the drive signal input from the PS controller 20. The pump inverter 32 supplies AC power to the electric motor 30 by controlling the switching element on and off, and controls the rotation direction and rotation speed of the electric motor 30.

The display panel 70 displays information or the like indicating a driving situation such as a vehicle speed. The display panel 70 is provided, for example, in the driver's cab on which the worker is boarding. Further, the menu screen of the display panel 70 is provided with an automatic refueling button for executing the automatic oil introduction program. When the automatic refueling button is selected and operated by the operator, an oil introduction command is input from the VCM 21 to the PS controller 20. That is, the display panel 70 functions as an input unit for inputting an oil introduction command. In addition to the display panel 70, an operation member for inputting an oil introduction command may be provided as an input unit.

The traveling inverter 81 is composed of a plurality of switching elements and the like, controls the switching elements on and off based on a signal input from the VCM 21, and supplies AC power to the traveling drive device 80. The traveling drive device 80 applies a traveling driving force to the tire 60 by using the AC power supplied from the traveling inverter 81.

The PS controller 20 has a first expansion / contraction control unit 23 and a second expansion / contraction control unit 24. The first expansion / contraction control unit 23 controls the steering cylinder 50 to be repeatedly expanded / contracted in both directions at the first speed for the first time. Based on the oil introduction command, the second expansion / contraction control unit 24 controls the steering cylinder 50 to repeatedly expand and contract in both directions at a second speed faster than the first speed until the second time elapses after the first time elapses.

Specifically, the first expansion / contraction control unit 23 repeatedly reverses the forward / reverse rotation of the double-rotation hydraulic pump 40 at the first rotation speed (for example, 300 rpm) for the first time (for example, 3 minutes). As a result, oil is automatically introduced into the hydraulic circuit and circulated. The first time is determined by the flow rate of oil from the external tank 100 (see FIG. 2) to the tank 43 of the forklift, the amount of oil that can be stored in the tank 43, and the like. The second expansion / contraction control unit 24 repeatedly reverses the forward rotation of the double-rotation hydraulic pump 40 at a second rotation speed (for example, 800 rpm) higher than the first rotation speed for the second time (for example, 2 minutes). As a result, the oil is introduced into the hydraulic circuit, and the air remaining in the hydraulic circuit is discharged through the tank 43, so that the air can be bleeded.

FIG. 4 is a flowchart illustrating an oil automatic introduction process executed by the forklift according to the embodiment. With reference to FIG. 4, automatic refueling and air bleeding using the automatic oil introduction program will be described.

In step S100, the VCM 21 determines whether or not the execution request of the oil automatic introduction function has been made, that is, whether or not the oil introduction command has been input. For example, the operator connects the external tank 100, which is an external oil supply source, and the tank 43 of the forklift via a tube or the like, and selects the automatic oil supply button on the display panel 70 to issue an oil introduction command. If an affirmative determination is made in step S100, the process proceeds to step S140, and if a negative determination is made in step S100, that is, if it is determined that the work process is normal rather than the oil introduction process (oil filling process), the process proceeds to step S110.

In step S110, the PS controller 20 determines whether or not the steering handle 11 has been operated by using the steering angle signal output from the steering angle sensor 12. If an affirmative determination is made in step S110, the process proceeds to step S120, and if a negative determination is made in step S110, the process returns to step S100.

In step S120, the PS controller 20 generates a drive signal based on the steering angle of the steering wheel 11. The PS controller 20 drives the electric motor 30 and the double-rotation hydraulic pump 40 by outputting a drive signal to the pump inverter 32, and steers the tire 60.

In step S130, the PS controller 20 determines whether or not the steering angle of the tire 60 calculated using the tire angle signal from the tire angle sensor 51 is an angle corresponding to the steering angle of the steering handle 11. .. If an affirmative determination is made in step S130, the process returns to step S100, and if a negative determination is made in step S130, the process returns to step S120. In step S120 when a negative determination is made in step S130, the PS controller 20 corrects the drive signal based on the calculated steering angle of the tire 60, and feedback-controls the electric motor 30.

Step S140 is a process executed when a positive determination is made in step 100, and the oil automatic introduction program is started. In response to the oil introduction command, the introduction of oil from the external tank 100 into the tank 43 is started. Oil is supplied to the tank 43 from the external tank 100 via a tube or the like at a predetermined flow rate. The first expansion / contraction control unit 23 of the PS controller 20 generates first and second drive signals for low-speed drive based on the oil introduction command. The first expansion / contraction control unit 23 outputs a first drive signal to the pump inverter 32 to repeatedly drive the double-rotation hydraulic pump 40 in forward / reverse rotation at a relatively low rotation speed (for example, 300 rpm).

Specifically, the first expansion / contraction control unit 23 outputs a first drive signal for low-speed drive for driving the electric motor 30 in the forward rotation at a low rotation speed to the pump inverter 32. The electric motor 30 and the double-rotation hydraulic pump 40 are driven in the forward rotation in response to the first drive signal. When the introduction of oil from the external tank 100 into the steering hydraulic circuit including the tank 43 progresses while the double-rotation hydraulic pump 40 is driven in the forward rotation, the steering cylinder 50 starts to expand and contract, and the tire 60 is gradually steered. Will be done. When the steering cylinder 50 moves in one direction, the tire 60 eventually reaches the position of the tire end. When the tire 60 reaches the position of the tire end, the tire 60 cannot move mechanically any more, and the current value flowing through the electric motor 30 tends to increase. The PS controller 20 detects the current value flowing through the electric motor 30 using a signal from a current sensor (not shown), and determines that the tire 60 has been steered to the position of the tire end when the current value is equal to or higher than a predetermined value. .. When it is determined that the tire 60 has reached the position of the tire end, the first expansion / contraction control unit 23 outputs a second drive signal for reversely driving the electric motor 30 at a low speed to the pump inverter 32. ..

When the electric motor 30 and the double-rotation hydraulic pump 40 are reversely driven and the steering cylinder 50 moves in the other direction, the tire 60 eventually reaches the position of the tire end. The first expansion / contraction control unit 23 determines that the tire 60 has been steered to the position of the tire end when the current value flowing through the electric motor 30 is equal to or higher than a predetermined value, and drives the electric motor 30 in the forward rotation at a low speed. 1 Outputs a drive signal. In this way, the first expansion / contraction control unit 23 alternately alternates between a first drive signal for driving the electric motor 30 in the forward rotation at a low rotation speed and a second drive signal for driving the electric motor 30 in the reverse direction at a low speed. Output to.

In step S150, the first expansion / contraction control unit 23 determines whether or not the first time (for example, 3 minutes) has elapsed since the low-speed drive of the double-rotation hydraulic pump 40 was started. If an affirmative determination is made in step S150, the process proceeds to step S160, and if a negative determination is made in step S150, the process returns to step S140. By repeatedly driving the double-rotation hydraulic pump 40 in the forward and reverse directions at a low rotation speed, the hydraulic circuit is filled with oil after the lapse of the first time.

In step S160, the second expansion / contraction control unit 24 of the PS controller 20 outputs the third and fourth drive signals for high-speed drive to the pump inverter 32 based on the oil introduction command, and makes the double-rotation hydraulic pump 40 relative to each other. The engine is repeatedly driven in the forward and reverse directions at a high rotation speed (for example, 800 rpm). Specifically, the second expansion / contraction control unit 24 reverses the third drive signal for driving the electric motor 30 in the forward rotation at a high rotation speed and the electric motor 30 at a high rotation speed with respect to the pump inverter 32. The fourth drive signal for driving is output alternately. More specifically, the second expansion / contraction control unit 24 determines whether or not the tire 60 has reached the tire end position using the current of the electric motor 30, as in the process in step S140 by the first expansion / contraction control unit 23. The determination is made, and the third drive signal and the fourth drive signal are switched according to the determination result.

In step S170, the second expansion / contraction control unit 24 determines whether or not a second time (for example, 2 minutes) has elapsed since the high-speed drive of the double-rotation hydraulic pump 40 was started. If an affirmative determination is made in step S170, the process proceeds to step S180, and if a negative determination is made in step S170, the process returns to step S160. During the second hour, the double-rotation hydraulic pump 40 is repeatedly driven in the forward and reverse directions at high and low rotation speeds, so that air bubbles mixed in the hydraulic circuit are discharged through the tank 43.

In step S180, the PS controller 20 determines that the oil automatic introduction work has been completed. The PS controller 20 displays information indicating that the oil automatic introduction work has been completed on the display panel 70, and returns to step S100. The PS controller 20 may output a voice message indicating that the oil automatic introduction work has been completed from the display panel 70 or the like.

In the forklift according to the embodiment, the refueling and bleeding operations are automatically performed according to the automatic oil introduction program. Therefore, it is possible to prevent air from remaining in the hydraulic circuit. In addition, it is possible to prevent variations in work by each worker and re-working. Furthermore, the work time for refueling and bleeding air can be shortened.

According to the above-described embodiment, the following effects can be obtained.
(1) The oil automatic introduction program of the embodiment is to be executed by a computer mounted on the PS controller 20 of the forklift when oil is introduced from the external oil supply source 100 into the steering hydraulic circuit 10 mounted on the forklift. Oil automatic introduction program. By this automatic oil introduction program, the computer of the PS controller 20 makes the steering cylinder 50 faster than the first speed after the first operation procedure of repeatedly expanding and contracting the steering cylinder 50 in both directions at the first speed and the second operation procedure. The second operation procedure of repeatedly expanding and contracting in both directions at a speed is sequentially executed. In the embodiment, the steering cylinder 50 repeatedly expands and contracts in a slow cycle according to the oil automatic introduction program, and then repeatedly expands and contracts in an early cycle. Therefore, refueling and air bleeding operations can be performed automatically. In addition, it is possible to prevent air from remaining in the hydraulic circuit.
(2) Since the refueling and air bleeding operations are automatically performed, it is possible to prevent the work from being varied by each worker and the work from being redone. In addition, the work time for refueling and bleeding air can be shortened.

(3) The oil introduction device of the embodiment is an oil introduction device that introduces oil from the external oil supply source 100 into the steering hydraulic circuit 10 mounted on the forklift based on the oil introduction command. This oil introduction device has a first expansion / contraction control unit 23 that repeatedly expands / contracts the steering cylinder 50 in both directions at a first speed for the first time, and a first expansion / contraction control unit 23 for the steering cylinder 50 until the second time elapses after the first time elapses. A second expansion / contraction control unit 24 that repeatedly expands / contracts in both directions at a second speed faster than the speed is provided. Since this is done, refueling and air bleeding can be performed automatically. In addition, it is possible to prevent air from remaining in the hydraulic circuit.
(4) The steering device of the embodiment discharges oil from the first or second discharge ports 41a and 41b to the first pipe line 42a or the second pipe line 42b based on the operation of the steering handle 11 and the steering handle 11. The double-rotation hydraulic pump 40, the control unit 20 that outputs a drive signal for driving the double-rotation hydraulic pump 40 based on the operation of the steering handle 11, and the oil discharged from the double-rotation hydraulic pump 40 are the first or second. It includes a steering cylinder 50 that is supplied via the pipelines 42a and 42b and expands and contracts in the first or second direction, and a tank 43 in which oil is stored. When the oil introduction command is input to the control unit 20, the control unit 20 repeatedly reverses the forward rotation of the double-rotation hydraulic pump 40 at the first rotation speed until the first time elapses, and after the first time elapses. Repeats the forward rotation and reverse rotation of the double rotation hydraulic pump 40 at a second rotation speed higher than the first rotation speed until the second time elapses. Since this is done, refueling and air bleeding can be performed automatically. In addition, it is possible to prevent air from remaining in the hydraulic circuit.

The following modifications are also within the scope of the present invention, and one or more of the modifications can be combined with the above-described embodiment.
(Modification example 1)
In the above embodiment, an example in which an oil automatic introduction program is mounted on the PS controller 20 of a forklift and the program is activated from the display panel 70 to automatically introduce oil has been described. However, the oil automatic introduction program may be implemented in the VCM 21. Further, for a forklift in which the oil automatic introduction program is not mounted in advance on the PS controller 20 or VCM 21, oil can be automatically introduced by using an electronic device for oil automatic introduction equipped with the oil automatic introduction program. ..

FIG. 5 is a block diagram showing an example of an electronic device equipped with the oil automatic introduction program according to the first modification. The electronic device (electronic jig) 90 for automatic oil introduction includes a display panel 91 having an input / output function for performing various settings, a processing device 92, a storage device 93 for storing a program, and an interface (I). / F) 94 is provided. The processing device 92 is a processor such as a CPU or FPGA, and the storage device 93 is a memory such as a ROM or RAM. The electronic jig 90 is, for example, a mobile device such as a tablet terminal, a notebook personal computer, or a smartphone. The interface 94 is an interface for connecting to the PS controller 20 and VCM 21 of the forklift. The data communication between the electronic jig 90 and the forklift may be performed by using a storage medium such as a USB memory or by wireless communication.

(Modification 2)
The program can be supplied to the forklift control device or the mobile device described above by, for example, infrared communication or short-range wireless communication from a personal computer storing the program. Further, the program may be supplied to the personal computer by setting a recording medium such as a CD-ROM in which the program is stored in the personal computer, or by loading the program into the personal computer via a communication line such as a network. You may. When going through a communication line, the program is stored in the storage device of the server connected to the communication line.

It is also possible to directly transmit the program to the mobile device via the wireless LAN access point connected to the communication line. Further, a recording medium such as a memory card in which the program is stored may be set in the mobile device. As described above, the program can be supplied as various forms of computer program products such as those provided via a recording medium or a communication line.

(Modification example 3)
Although the present invention has been described by taking a forklift as an example in the above embodiment, the present invention can be applied to a traveling vehicle other than the forklift. That is, it can be applied to various traveling vehicles having a by-wire type steering device such as a wheel loader in which an electric steering command is output from a steering operation member and the steering cylinder expands and contracts in both directions to drive and control the tires. The present invention can also be applied to various traveling vehicles having a power steering mechanism for operating the steering using the power of a motor and a mechanism for manually operating the steering of the vehicle.

Although various embodiments and modifications have been described above, the present invention is not limited to these contents. Other aspects conceivable within the scope of the technical idea of the present invention are also included within the scope of the present invention.

10 Steering hydraulic circuit, 11 Steering handle, 20 PS controller, 21 VCM, 23 1st expansion and contraction control unit, 24 2nd expansion and contraction control unit, 30 Electric motor, 40-car rotary hydraulic pump, 43 tank, 50 Steering cylinder

Claims (8)

In an automatic oil introduction program for a computer to execute oil when introducing oil from an external oil source into a steering hydraulic circuit mounted on a traveling vehicle.
The first operation procedure of repeatedly expanding and contracting the steering cylinder in both directions at the first speed,
After the first operation procedure , the computer is sequentially executed with the second operation procedure of repeatedly expanding and contracting the steering cylinder in both directions at a second speed faster than the first speed.
The first and second operation procedures are an oil automatic introduction program performed by rotating both rotary hydraulic pumps in the forward and reverse directions. In the oil automatic introduction program according to claim 1,
In the first operation procedure, the first operation of rotating the double-rotation hydraulic pump in the forward and reverse directions is repeated at the first rotation speed until the first time elapses.
In the second operation procedure, after the first time elapses, until the second time elapses, the second operation of rotating the double-rotation hydraulic pump in the forward and reverse directions at a second rotation speed higher than the first rotation speed is performed. Repeated automatic oil introduction program. Implement the automatic oil introduction program according to claim 1 or 2,
An electronic device having an interface connected to the computer of the traveling vehicle in order to cause the computer of the traveling vehicle to execute the first and second operation procedures. In an oil introduction device that introduces oil from an external oil supply source into the steering hydraulic circuit mounted on a traveling vehicle based on the oil introduction command.
A first expansion / contraction control unit that repeatedly expands / contracts the steering cylinder in both directions at the first speed for the first time,
It is provided with a second expansion / contraction control unit that repeatedly expands / contracts the steering cylinder in both directions at a second speed faster than the first speed until the second time elapses after the lapse of the first time.
The first expansion / contraction control unit repeatedly reverses the forward / reverse rotation of the double-rotation hydraulic pump that supplies oil to the steering cylinder at the first rotation speed for the first hour.
The second expansion / contraction control unit is an oil introduction device that repeatedly reverses forward and reverse rotation of the double-rotation hydraulic pump for a second time at a second rotation speed higher than the first rotation speed. In the oil introduction device according to claim 4,
An oil introduction device that operates the first and second expansion / contraction control units by inputting the oil introduction command from the outside of the traveling vehicle. In the oil introduction device according to claim 4,
An oil introduction device that starts introducing oil into the steering hydraulic circuit by inputting the oil introduction command from an input unit mounted on the traveling vehicle. With the steering wheel
A birotary hydraulic pump that discharges oil from the first or second discharge port to the first pipe or the second pipe based on the operation of the steering handle.
A control unit that outputs a drive signal for driving the double-rotation hydraulic pump based on the operation of the steering handle, and a control unit.
A steering cylinder in which oil discharged from the birotary hydraulic pump is supplied via the first or second pipeline and expands and contracts in the first or second direction.
Equipped with a tank for storing the oil
When the oil introduction command is input to the control unit, the control unit repeatedly reverses the forward rotation of the double-rotation hydraulic pump at the first rotation speed until the first time elapses, and the first time elapses. After that, until the second time elapses, the steering device repeatedly rotates the double-rotation hydraulic pump in the forward and reverse directions at a second rotation speed higher than the first rotation speed. The steering device according to claim 7 and
A traveling vehicle having a traveling driving device that applies a traveling driving force to the tires steered by the steering device.

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