JP2018004011A - Traveling control device, working vehicle, and traveling control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a traveling control device or the like which can control a vehicle so as to be travelable only when an operator wears a seatbelt.SOLUTION: Traveling command hydraulic pressure which is obtained by distributing operator command hydraulic pressure outputted from a traveling pump 51 by a hydraulic pressure distributor 52 is inputted to an oil passage changeover switch 53, and the oil passage changeover switch 53 switches an oil passage according to whether or not the wearing of a seatbelt is detected. When the wearing of the seatbelt is detected, the traveling command hydraulic pressure is outputted to a left traveling valve 54 and a right traveling valve 55 from the oil passage changeover switch 53. Then, by forwardly operating or backwardly operating a left traveling lever or a right traveling lever, the traveling command hydraulic pressure is outputted to the traveling pump 51 from the left traveling valve 54 or the right traveling valve 55, and the traveling pump 51 outputs traveling hydraulic pressure to a left traveling device 21 and a right traveling device 22 on the basis of the inputted traveling command hydraulic pressure, and drives them for traveling.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a travel control device, a work vehicle, and a travel control method for controlling travel of a vehicle.

  A transport vehicle that transports timber, earth and sand, etc. in a forest is often equipped with a traveling device composed of an endless track. In such a vehicle, the engine is driven to output hydraulic pressure to the traveling device or the cargo platform elevating device to travel or elevate the cargo platform.

  This transport vehicle has a driver seat, and an operator seated in the driver seat operates an operation lever, an operation switch, and the like. For safety reasons, it is desirable for the operator to wear a seat belt when sitting.

  In order to securely attach the seat belt, a technique is known in which the engine is driven only when the seat belt is worn in an ordinary automobile or the like. In addition, a technique is known that enables a work machine to be driven only when a seat belt is mounted in a civil engineering work vehicle or a construction vehicle (for example, Patent Document 1).

  The construction machine described in Patent Literature 1 includes a pilot valve that outputs pilot hydraulic pressure according to an operation amount, a control valve that controls the amount of hydraulic oil supplied to the work machine, and hydraulic oil that is supplied to the pilot valve and the control valve. When the seat belt is not attached to the operator, the hydraulic circuit communicating with the hydraulic pump and the pilot valve can be shut off so that the work machine can be controlled not to be driven. doing.

JP 2012-21362 A

  In transport vehicles that transport timber and earth and sand in the forest, forward and backward travel control is performed with the travel lever provided in the driver's seat, but the surrounding people accidentally travel even when there is no operator in the driver's seat Touching the lever may start running, which is very dangerous. In addition, it is necessary to ensure that the seat belt is attached during traveling and to improve the safety of the operator in the event of an accident such as a collision.

  On the other hand, for such a maintenance vehicle, there is a case where only the engine is driven for maintenance, and the operator leaves the driver's seat and performs maintenance in a state where traveling is stopped. In addition, during work in the forest, the operator may leave the driver's seat and operate the platform lifting device while traveling is stopped.

  In other words, only when the operator is seated in the driver's seat and the seat belt is attached, the forward and backward travel is controlled, and even when the operator is not seated in the driver's seat, the engine is driven, Although the form which makes it operate | moved is suitable for the actual condition of work, there was no conveyance vehicle of such a form conventionally.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a travel control device and the like that can be controlled to be able to travel only when an operator wears a seat belt.

In order to achieve the above object, a travel control device according to a first aspect of the present invention provides:
A traveling pump that outputs traveling hydraulic pressure and operation command hydraulic pressure by driving the engine;
A detection unit for detecting the wearing of the seat belt;
When at least a part of the operation command hydraulic pressure is input, a travel command hydraulic pressure is input, and the detection unit outputs the travel command hydraulic pressure when detecting the seat belt mounting, and the detection unit detects the seat belt mounting. An oil passage changeover switch that switches the oil passage so as to release the travel command oil pressure when not
A travel valve that receives the travel command hydraulic pressure from the oil path changeover switch and outputs or releases the travel command hydraulic pressure to the travel pump in accordance with the presence or absence of a travel operation by an operator;
The travel pump outputs the travel hydraulic pressure to a travel device only when the travel command hydraulic pressure is input from the travel valve.
It is characterized by that.

A hydraulic distributor that distributes the operation command oil pressure output from the travel pump to the travel command oil pressure and a work command oil pressure used to control a work implement;
The travel command hydraulic pressure output from the hydraulic distributor may be input to the oil path switch.

The oil path changeover switch includes a first input terminal, a first output terminal, and a second output terminal, the A block that terminates the first input terminal and short-circuits the first output terminal and the second output terminal. The first input terminal and the first output terminal are short-circuited and the second output terminal is terminated. The block B is slid between the A block and the B block to switch the oil path, and the detection When the part detects the seat belt being mounted, the travel command hydraulic pressure is output through the first input terminal and the first output terminal of the B block,
The travel valve includes a second input terminal and a third input terminal,
Connecting the first output terminal of the oil path switch to the second input terminal of the travel valve, connecting the second output terminal of the oil path switch to the third input terminal of the travel valve; The hydraulic pressure is released by connecting the second output terminal of the oil passage changeover switch to an oil tank,
When the operator performs a forward or reverse operation, the travel command hydraulic pressure input from the second input terminal of the travel valve may be output to the travel pump.

The traveling device comprises a left traveling device and a right traveling device,
The travel valve consists of a left travel valve and a right travel valve,
The travel command hydraulic pressure is input from the oil path switch to each of the left travel valve and the right travel valve,
The travel pump outputs the travel hydraulic pressure to the left travel device only when the travel command hydraulic pressure is input from the left travel valve, and only when the travel command hydraulic pressure is input from the right travel valve. May be output to the right traveling device.

  Moreover, the work vehicle which concerns on the 2nd viewpoint of this invention is provided with the traveling control apparatus which concerns on a 1st viewpoint.

A travel control method according to the third aspect of the present invention is as follows.
A travel control method for a travel device that travels by input of travel hydraulic pressure from a travel pump,
A detection step for detecting the wearing of the seat belt;
Oil path switching that outputs a travel command oil pressure when the seat belt is detected in the detection step and switches the oil path so as to release the travel command oil pressure when the seat belt is not detected in the detection step. Steps,
A supply step of supplying the travel command hydraulic pressure to the travel pump according to the presence or absence of the travel operation of the operator when the travel command hydraulic pressure is output in the oil path switching step;
A travel step of traveling by outputting the travel hydraulic pressure to the travel device only when the travel command hydraulic pressure is supplied to the travel pump in the supplying step;
It is characterized by having.

  According to the present invention, the vehicle can be controlled to run only when the operator wears the seat belt.

1 is an external view of a transport vehicle according to an embodiment of the present invention. It is the figure which showed the inside of a driver's seat, (a) is a side view, (b) is a top view. It is the figure which showed the traveling control apparatus and the peripheral device. It is the figure which showed the traveling control apparatus and peripheral circuit at the time of seat belt non-wearing. It is the figure which showed the traveling control apparatus and peripheral circuit at the time of seat belt wearing and advancing. It is the figure which showed the travel control apparatus and peripheral circuit at the time of seatbelt wearing and reverse drive.

(Embodiment)
Embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is an external view of a transport vehicle 1 according to the present embodiment. As shown in FIG. 1, the transport vehicle 1 includes a driver's seat 10, a traveling device 20, and a loading platform 30. The box 18 beside the driver's seat 10 is provided with an engine 40 and a travel control device 50, and a cargo bed elevating device 60 is provided below the cargo bed 30.

  The traveling device 20 includes a left traveling device 21 and a right traveling device 22 and is configured by an endless track. By driving the engine 40, the traveling hydraulic pressure is output from the traveling pump 51 of the traveling control device 50 to the traveling device 20, and the left traveling device 21 or the right traveling device 22 is rotationally driven according to the traveling direction.

  The loading platform 30 is loaded with wood, earth and sand. The inclination of the loading platform 30 is changed by extending and contracting the hydraulic cylinder of the loading platform lifting device 60. Thereby, the load loaded on the loading platform 30 can be unloaded.

  2A and 2B are views showing the inside of the driver's seat 10, where FIG. 2A is a view seen from the side, and FIG. 2B is a view seen from above. As shown in FIG. 2, the driver's seat 10 has a seat 11, a seat belt 12, a left traveling lever 13 that performs a forward or reverse selection operation of the left traveling device 21, and a forward or backward selection operation of the right traveling device 22. A right travel lever 14 is provided. Further, near the seat 11 at the top of the box 18 in which the engine 40 and the travel control device 50 are stored, there are provided a throttle lever 15 for operating the rotation adjustment of the engine 40 and a loading platform lifting lever 16 for controlling the lifting and lowering of the loading platform 30.

  In FIG. 2, the seat belt 12 is shown in a retracted state. After the operator is seated on the seat 11, the seat belt 12 is pulled out and inserted into the fixture 17 on the opposite side to be fixed and attached. The fixing device 17 has a built-in seat belt detection unit. When the front end of the seat belt 12 is fixed to the fixing device 17, the seat belt detection unit detects that the seat belt 12 is mounted, and detects a detection signal. Is output.

  FIG. 3 is a diagram showing the configuration of the travel control device 50 and its peripheral devices. The traveling control device 50 includes a hydraulic circuit as shown in FIG. 3, and outputs the traveling hydraulic pressure to the left traveling device 21 and the right traveling device 22 by driving the engine 40, and the lifting hydraulic pressure to the loading platform lifting device 60. A traveling pump 51 for outputting is provided. The travel control device 50 includes a hydraulic distributor 52 that distributes the operation command hydraulic pressure output from the travel pump 51, and an oil path switch 53 that switches an output destination of the travel command hydraulic pressure output from the hydraulic distributor 52. Prepare. Further, the travel control device 50 includes a left travel valve 54 and a right travel valve 55 to which the travel command hydraulic pressure that has passed through the oil path changeover switch 53 is input.

  The oil passage changeover switch 53 is a switch that switches the oil passage according to a detection signal input from the seat belt detection unit, and has one input terminal and two output terminals (a terminal and b terminal). As shown in FIG. 3, the oil path changeover switch 53 has an A block in which the input terminal is terminated and the a terminal and the b terminal of the output terminal are short-circuited, and the input terminal and the a terminal are short-circuited in the b terminal. And the B block that is terminated. The A block and the B block are joined to each other, and the oil path is switched by sliding in a direction perpendicular to the joining surface. Since the b terminal of the hydraulic pressure changeover switch 53 is connected to the hydraulic oil tank 56, the hydraulic pressure is always released and the low level hydraulic pressure is maintained.

  The left travel valve 54 and the right travel valve 55 each have a P terminal and a T terminal which are input terminals, and the P terminal is connected to the a terminal of the hydraulic pressure changeover switch 53. On the other hand, the T terminal is connected to the b terminal of the hydraulic pressure changeover switch 53. For this reason, the hydraulic pressure is always released at the T terminal, and the low level hydraulic pressure is maintained.

  The left travel valve 54 outputs the travel command hydraulic pressure input from the oil path changeover switch 53 to the drive control unit of the left travel device 21 in the travel pump 51 based on the operation of the left travel lever 13. The left travel valve 54 outputs the travel command hydraulic pressure input from the P terminal when the left travel lever 13 is tilted forward from the LF terminal corresponding to the forward movement, and from the P terminal when the left travel lever 13 is tilted backward. The travel command hydraulic pressure is output from the LB terminal corresponding to the reverse travel.

  Since the left travel valve 54 is in a state where the T terminal, the LF terminal, and the LB terminal are connected when the left travel lever 13 is not tilted forward or backward, the travel command hydraulic pressure output from the left travel valve 54 is It is released and keeps the Low level.

  Similarly, the right travel valve 55 outputs the travel command hydraulic pressure input from the oil passage changeover switch 53 to the drive control unit of the right travel device 22 in the travel pump 51 based on the operation of the right travel lever 14. The right travel valve 55 outputs the travel command hydraulic pressure input from the P terminal when the right travel lever 14 is tilted forward from the RF terminal corresponding to the forward movement, and from the P terminal when the right travel lever 14 is tilted backward. The input travel command hydraulic pressure is output from the RB terminal corresponding to the reverse travel.

  Since the right travel valve 55 is in a state where the T terminal, the RF terminal, and the RB terminal are connected when the right travel lever 14 is not tilted forward or backward, the travel command hydraulic pressure output from the right travel valve 55 is It is released and keeps the Low level.

  The operation of the transport vehicle 1 configured as described above will be described in detail.

  First, the operator of the transport vehicle 1 turns on the engine switch to drive the engine 40. For the safety of the operator and surrounding people, the operator wears a seat belt when the transport vehicle 1 is traveling. On the other hand, when performing maintenance or loading / unloading without transporting the transport vehicle 1, the operator may work without being seated or with the seat belt removed.

  FIG. 4 shows a hydraulic pressure state of the travel control device 50 when the seat belt is not attached. A solid line indicates an oil path with a high oil pressure, and a broken line indicates an oil path with a low oil pressure. When the operator is not seated or works while seated and the seat belt is removed, the seat belt 12 is not worn, so the detection signal from the seat belt detector indicates not worn. Based on the detection signal, the oil passage changeover switch 53 is in a state where the oil passage from the hydraulic distributor 52 is connected to the A block as shown in FIG.

  For this reason, the P terminal and the T terminal of the left travel valve 54 and the right travel valve 55 are short-circuited, and the hydraulic oil is discharged from the T terminal to the hydraulic oil tank 56. The oil pressure between the travel valve 54 and the right travel valve 55 is released to a low level.

  Here, the operator or another person in the vicinity accidentally touches the left traveling lever 13 or the right traveling lever 14 to tilt the lever, and the P terminals of the left traveling valve 54 and the right traveling valve 55 are coupled to the output terminals. Even in this case, the oil passage connected from the left travel valve 54 and the right travel valve 55 to the travel pump 51 maintains the low level hydraulic pressure.

  Accordingly, the traveling pump 51 does not output the traveling hydraulic pressure from the traveling pump 51 to the left traveling device 21 and the right traveling device 22 in response to the traveling command hydraulic pressure being at the low level. That is, the left traveling device 21 and the right traveling device 22 are not travel driven.

  On the other hand, the lifting command hydraulic pressure input from the hydraulic distributor 52 to the lifting valve 57 is output to or released from the loading platform lifting device 60 based on the operation of the loading platform lifting lever 16. At this time, since the lift hydraulic pressure is output from the traveling pump 51 to the platform lifting device 60, the hydraulic cylinder expands and contracts based on the lift command hydraulic pressure.

  Next, the operation when the operator wears the seat belt 12 will be described. 5 and 6 show the hydraulic state of the travel control device 50 when the seat belt is mounted. The solid line indicates an oil passage with a high oil pressure, and the broken line indicates an oil passage with a low oil pressure. When the operator wears the seat belt 12, the detection signal from the seat belt detection unit indicates the wearing. Based on the detection signal, the oil passage changeover switch 53 is in a state where the oil passage from the hydraulic distributor 52 is connected to the B block as shown in FIGS.

  Therefore, the input terminal of the oil path changeover switch 53 is connected to the P terminals of the left travel valve 54 and the right travel valve 55, and the oil path changeover switch 53, the left travel valve 54, and the P terminal of the right travel valve 55 are connected. The oil path between is high hydraulic pressure.

  Here, when the right traveling lever 13 and the left traveling lever 14 are tilted forward for the operator to move forward, as shown in FIG. 5, the P terminals of the left traveling valve 54 and the right traveling valve 55 become the LF terminal and the RF terminal. Shorted to the terminal. As a result, the travel command hydraulic pressure is output from the LF terminal of the left travel valve 54 and the RF terminal of the right travel valve 55, and the oil passage connected to the travel pump 51 becomes a high level hydraulic pressure.

  The traveling pump 51 outputs the traveling hydraulic pressure in the forward direction from the traveling pump 51 to the left traveling device 21 and the right traveling device 22 in response to the traveling command hydraulic pressure being input from the LF terminal and the RF terminal. As a result, the left traveling device 21 and the right traveling device 22 are driven forward. At this time, the traveling speed can be arbitrarily adjusted by operating the throttle lever 15 for adjusting the rotation of the engine 40.

  On the other hand, when the operator moves the right travel lever 13 and the left travel lever 14 backward to move backward, as shown in FIG. 6, the P terminals of the left travel valve 54 and the right travel valve 55 are the LB terminal and the RB terminal. And shorted. As a result, the travel command hydraulic pressure is output from the LB terminal of the left travel valve 54 and the RB terminal of the right travel valve 55, and the oil passage connected to the travel pump 51 becomes a high level hydraulic pressure.

  The traveling pump 51 outputs the traveling hydraulic pressure in the backward direction from the traveling pump 51 to the left traveling device 21 and the right traveling device 22 in response to the traveling command hydraulic pressure being input from the LB terminal and the RB terminal. As a result, the left traveling device 21 and the right traveling device 22 are driven backward. At this time, the traveling speed can be arbitrarily adjusted by operating the throttle lever 15 for adjusting the rotation of the engine 40.

  As for the control of the platform lifting device 60, the lift command hydraulic pressure input to the lift valve 57 from the hydraulic distributor 52 is based on the operation of the platform lifting lever 16 when the seat belt is worn and when the seat belt is not worn. It is output to the lifting device 60 or released. At this time, since the lift hydraulic pressure is output from the traveling pump 51 to the platform lifting device 60, the hydraulic cylinder expands and contracts based on the lift command hydraulic pressure.

  5 and 6, the case where the left traveling device 21 and the right traveling device 22 move forward or backward when both the left traveling lever 13 and the right traveling lever 14 are tilted forward or when both are tilted backward will be described. However, by tilting only the left travel lever 13 forward or backward, only the travel command hydraulic pressure output from the LF terminal or the LB terminal becomes High level, and only the left travel device 21 is driven forward or backward. This makes a right turn. Similarly, by tilting only the right travel lever 14 forward or backward, only the travel command hydraulic pressure output from the RF terminal or the RB terminal becomes High level, and only the right travel device 22 is driven forward or backward. This makes a left turn.

  As described above, in the present embodiment, the travel command hydraulic pressure obtained by distributing the operation command hydraulic pressure output from the travel pump 51 by the hydraulic distributor 52 is input to the oil path switch 53, and the oil path switch 53 is The oil passage is switched according to whether the seat belt is detected or not. When the wearing of the seat belt is detected, the travel command hydraulic pressure is output from the oil passage changeover switch 53 to the left travel valve 54 and the right travel valve 55. Then, when the left travel lever 13 or the right travel lever 14 is operated forward or backward, the travel command hydraulic pressure is output from the left travel valve 54 or the right travel valve 55 to the travel pump 51. The traveling pump 51 outputs the traveling hydraulic pressure to the left traveling device 21 and the right traveling device 22 based on the input traveling command oil pressure to drive the traveling. Thereby, the left traveling device 21 and the right traveling device 22 can be driven to travel according to the operation of the left traveling lever 13 or the right traveling lever 14 only when the seat belt is detected.

  As described above, the present invention outputs the travel command hydraulic pressure when the oil passage changeover switch to which at least a part of the operation command hydraulic pressure output from the travel pump is input detects the seat belt being attached, The oil passage is switched so that the travel command hydraulic pressure is released when the belt is not detected, and the travel valve applies the travel command hydraulic pressure input from the oil path switch to the travel pump according to the travel operation of the operator. The traveling pump outputs the traveling hydraulic pressure to the traveling device only when the traveling command hydraulic pressure is input from the traveling valve. Thereby, it can control so that driving | running | working is possible only when an operator wears a seatbelt.

  In addition, this invention is not limited to the said embodiment, Of course, the various change in the range which does not deviate from the summary of this invention is possible.

  For example, although this embodiment demonstrated the traveling control apparatus 50 of the conveyance vehicle 1 which conveys earth and sand and wood, you may apply this traveling control apparatus 50 to another work vehicle. For example, the present invention may be applied to travel control of various work vehicles such as a crushing work vehicle and an excavation work vehicle. In this case, the command pressure distributed by the hydraulic distributor 52 is distributed to the travel command hydraulic pressure and the command pressure for other work.

  In addition, although the oil path selector switch 53 is switched based only on the detection signal indicating whether the seat belt 12 is mounted or not mounted, the switching may be performed based on the result of multiplication with other detection signals. For example, by detecting whether the operator is seated or not seated with a pressure sensor installed on the seat 11 and switching based on the result of multiplying the detection signal and the seat belt detection signal, the operator can sit and The traveling device 20 may travel only when it is attached.

DESCRIPTION OF SYMBOLS 1 ... Transport vehicle 10 ... Driver's seat 11 ... Seat 12 ... Seat belt 13 ... Left travel lever 14 ... Right travel lever 15 ... Throttle lever 16 ... Cargo lift lever 17 ... Fixing tool 18 ... Box 20 ... Travel device 21 ... Left travel device DESCRIPTION OF SYMBOLS 22 ... Right travel apparatus 30 ... Loading platform 40 ... Engine 50 ... Travel control apparatus 51 ... Travel pump 52 ... Hydraulic distributor 53 ... Oil path changeover switch 54 ... Left travel valve 55 ... Right travel valve 56 ... Hydraulic oil tank 57 ... Lift valve 60. Loading platform lifting device

Claims (6)

A traveling pump that outputs traveling hydraulic pressure and operation command hydraulic pressure by driving the engine;
A detection unit for detecting the wearing of the seat belt;
When at least a part of the operation command hydraulic pressure is input, a travel command hydraulic pressure is input, and the detection unit outputs the travel command hydraulic pressure when detecting the seat belt mounting, and the detection unit detects the seat belt mounting. An oil passage changeover switch that switches the oil passage so as to release the travel command oil pressure when not
A travel valve that receives the travel command hydraulic pressure from the oil path changeover switch and outputs or releases the travel command hydraulic pressure to the travel pump in accordance with the presence or absence of a travel operation by an operator;
The travel pump outputs the travel hydraulic pressure to a travel device only when the travel command hydraulic pressure is input from the travel valve.
Travel control device. A hydraulic distributor that distributes the operation command oil pressure output from the travel pump to the travel command oil pressure and a work command oil pressure used to control a work implement;
The travel command hydraulic pressure output from the hydraulic distributor is input to the oil passage changeover switch.
The travel control device according to claim 1. The oil path changeover switch includes a first input terminal, a first output terminal, and a second output terminal, the A block that terminates the first input terminal and short-circuits the first output terminal and the second output terminal. The first input terminal and the first output terminal are short-circuited and the second output terminal is terminated. The block B is slid between the A block and the B block to switch the oil path, and the detection When the part detects the seat belt being mounted, the travel command hydraulic pressure is output through the first input terminal and the first output terminal of the B block,
The travel valve includes a second input terminal and a third input terminal,
Connecting the first output terminal of the oil path switch to the second input terminal of the travel valve, connecting the second output terminal of the oil path switch to the third input terminal of the travel valve; The hydraulic pressure is released by connecting the second output terminal of the oil passage changeover switch to an oil tank,
When the operator performs forward or reverse operation, the travel command hydraulic pressure input from the second input terminal of the travel valve is output to the travel pump;
The travel control device according to claim 1 or 2. The traveling device comprises a left traveling device and a right traveling device,
The travel valve consists of a left travel valve and a right travel valve,
The travel command hydraulic pressure is input from the oil path switch to each of the left travel valve and the right travel valve,
The travel pump outputs the travel hydraulic pressure to the left travel device only when the travel command hydraulic pressure is input from the left travel valve, and only when the travel command hydraulic pressure is input from the right travel valve. To the right traveling device,
The travel control device according to any one of claims 1 to 3.   A work vehicle comprising the travel control device according to any one of claims 1 to 4. A travel control method for a travel device that travels by input of travel hydraulic pressure from a travel pump,
A detection step for detecting the wearing of the seat belt;
Oil path switching that outputs a travel command oil pressure when the seat belt is detected in the detection step and switches the oil path so as to release the travel command oil pressure when the seat belt is not detected in the detection step. Steps,
A supply step of supplying the travel command hydraulic pressure to the travel pump according to the presence or absence of the travel operation of the operator when the travel command hydraulic pressure is output in the oil path switching step;
A travel step of traveling by outputting the travel hydraulic pressure to the travel device only when the travel command hydraulic pressure is supplied to the travel pump in the supplying step;
A travel control method comprising:

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