JP6071601B2 - Vehicle braking device - Google Patents

Description

  The present invention relates to a wheel driving means for rotationally driving a wheel, a brake device for applying a braking force to the wheel, and a brake for controlling the wheel by applying a braking force according to the operation of the brake operating means to the wheel by the brake device. The present invention relates to a vehicle braking device including a control device.

  2. Description of the Related Art Conventionally, a vehicle configured to travel by rotating a wheel by a hydraulic motor or an electric motor is known. For example, in a vehicle disclosed in Patent Document 1, a hydraulic pump is driven by an engine, and a wheel drive device having a closed circuit configuration that supplies oil discharged from the hydraulic pump to a hydraulic motor to drive the hydraulic motor to rotate is provided. The hydraulic motor is configured to run by rotating the wheels. Further, the wheel driving device of Patent Document 2 is configured to be switchable so as to allow free rotation of the wheel by opening a bypass oil passage that short-circuits the supply-side oil passage and the discharge-side oil passage connected to the hydraulic motor. The vehicle is towed while being switched to allow free rotation of the wheels.

Japanese Patent Laid-Open No. 2003-326931 JP 2009-293689 A

  By the way, in the vehicle as described above, when the brake operation means is operated while the wheel is driven by the wheel driving device, the engine braking action (for example, the engine braking action) caused by the rotational resistance of the wheel driving device is operated. Etc.) and a braking force is applied to the wheel by the brake device to brake the wheel. However, when the vehicle is towed while switching to allow the wheel to rotate freely by opening the bypass oil passage as in the wheel drive device of Patent Document 2, the engine brake action in the wheel drive device hardly acts. There is a problem that only the braking force by the brake device is used, and the braking distance of the vehicle becomes long.

  The present invention has been made in view of such problems, and provides a braking device for a vehicle that can prevent the braking distance of the vehicle from becoming long when the engine braking action by the wheel driving device does not act during towing. The purpose is to do.

In order to solve the above-described problems, a vehicle braking apparatus according to the present invention includes a vehicle body having wheels (for example, the iron wheel 12 in the embodiment) and wheel driving means for rotating the wheels (for example, implementation). Iron wheel travel motors 13L, 13R and hydraulic drive device 80) in the embodiment, a brake device for applying a braking force to the wheels, brake operation means for operating the brake device (for example, the brake pedal 68 in the embodiment), A brake control device for controlling the brake device by operating the brake device according to the operation of the brake operation means, and applying the braking force according to the operation amount of the brake operation means to the wheels by the brake device. For example, the body part controller 55) in the embodiment is provided, and the wheel driving means performs free rotation of the wheel. Configured to be capable of switching to capacity. When the brake operation unit is operated while the vehicle is running with the wheel being driven to rotate by the wheel driving unit, the brake control device performs an engine braking action (for example, caused by the rotational resistance of the wheel driving unit (for example, In addition to the engine braking force EB) in the embodiment, the brake device controls the wheel by braking the wheel by applying the braking force (for example, the braking brake force MB in the embodiment) to the wheel. When the brake operating means is operated when the vehicle is towed while switching so as to allow free rotation of the wheel, the brake device gives the wheel the amount by which the engine braking action does not act on the wheel. Control to increase in braking force, and increased braking force (e.g., embodiment Configured to definitive traction control brake force MB ') to perform a control to brake the wheel gives to the wheel.

  According to the vehicle braking apparatus of the present invention, when the vehicle is towed by switching the wheel driving means so as to allow free rotation of the wheel, the engine braking action in the wheel driving means does not act on the wheels. Is controlled to increase the braking force applied to the wheel by the brake device, and the increased braking force is applied to the wheel to brake the wheel. Therefore, it is possible to prevent the braking distance of the vehicle from becoming long when the engine braking action by the wheel drive device does not act during towing.

It is a side view of a track-and-rail work vehicle provided with the braking device concerning the present invention. It is a block diagram which shows the control system in the said railroad work vehicle. It is a hydraulic circuit diagram which shows the power system in the said track-and-rail work vehicle. It is a graph which shows an example of the braking force when braking operation is carried out while driving | running | working driving | running | working a traveling motor. It is a graph which shows an example of the braking force when braking operation is carried out while towing.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a track-and-rail work vehicle 1 as an example of a vehicle equipped with a braking device according to the present invention. The track-and-rail work vehicle 1 has a driving cab 4 at the front portion of a vehicle body 2, and a pair of left and right tire wheels 3 (road driving wheels) disposed on the front and rear of the vehicle body 2 are driven by the power of an engine E. It is based on a truck vehicle that can run on top.

  A pair of left and right iron wheel support members 11 are disposed in front of and behind the vehicle body 2 (rear side of each tire wheel 3), and an iron wheel 12 is rotatably disposed at the tip of each iron wheel support member 11. Yes. The front left and right iron wheels 12 and 12 are respectively connected to the output shafts of the left and right iron wheel traveling motors 13L and 13R (see FIG. 3), and the outputs of the iron wheel traveling motors 13L and 13R are connected to a reduction gear (not shown). It is comprised so that it may be rotationally driven by transmitting via. The iron wheel travel motors 13L and 13R are driven by a hydraulic drive device 80 described later. The track-and-rail work vehicle 1 is configured to be able to travel on the track by rotationally driving the left and right iron wheels 12 and 12 by the iron wheel traveling motors 13L and 13R.

  The steel wheel support member 11 is attached to the vehicle body 2 so as to be swingable in the vertical direction. The steel wheel support member 11 is rocked up and down by a telescopic operation of a steel wheel extension cylinder (not shown) provided therein so that the steel wheel 12 is moved from the tire wheel 3. It is configured so that it can project downward or be stored upward. In order to overhang and store the iron wheel 12 (in order to transfer and move the railroad work vehicle 1 onto the track), a turntable 15 is provided at the center lower portion of the vehicle body 2 so as to be vertically extendable. The turntable 15 is supported in a state where the turntable 15 is extended downward by a telescopic operation of a turntable cylinder (not shown) provided therein and the vehicle is lifted (the tire wheel 3 is lifted from the ground). It is configured to be able to.

  Jacks 17 that can be expanded and contracted in the vertical direction are arranged at four positions on the front and rear, left and right of the vehicle body 2. The jack 17 is supported when the vehicle is lifted downward by an extension operation of a jack cylinder (not shown) provided therein, and the vehicle is lifted, and is used when working at a high place using a boom 25 or the like described later. It is comprised so that can be stabilized.

  A swivel base 20 that is driven by a swivel motor (not shown) and configured to be able to swivel horizontally is provided at the front of the body region behind the driving cab 4 in the vehicle body 2. A boom 25 is attached to the upper part of the swivel base 20 by a foot pin 22 so as to be swingable (can be raised and lowered) in the vertical direction.

  The boom 25 is configured by nesting a base end boom 25a, an intermediate boom 25b, and a front end boom 25c, which are attached to the swivel base 20 by a foot pin 22 so as to be raised and lowered. A telescopic cylinder (not shown) is provided inside the boom 25, and the boom 25 is expanded and contracted in the longitudinal direction by relatively moving the booms 25a, 25b, and 25c by the expansion and contraction operation of the telescopic cylinder. It is configured to be able to. A hoisting cylinder 27 is straddled between the base end boom 25a and the swivel base 20, and the boom 25 can be hoisted in the upper and lower surfaces by operating the hoisting cylinder 27 to extend and contract. Yes.

  A worktable support bracket 28 is attached to the distal end portion of the distal end boom 25c so as to be swingable within the undulating surface (upper and lower surfaces) of the boom 25. The work table support bracket 28 is leveled by a leveling mechanism (not shown) so that the upper surface of the work table support bracket 28 is always held horizontally regardless of the angle of the boom 25. A work table 30 is attached to the upper surface of the work table support bracket 28 so as to be horizontally rotatable. A swing motor (not shown) is provided inside the work table support bracket 28. By driving the swing motor, the work table 30 is swung horizontally with respect to the work table support bracket 28 (swing operation). ). As described above, since the upper surface of the worktable support bracket 28 is always held horizontally, the floor surface of the worktable 30 is also held horizontally regardless of the undulation angle of the boom 30.

  The iron wheel overhang cylinder, the turntable cylinder, the jack cylinder, the turning motor, the telescopic cylinder, the hoisting cylinder, and the swinging motor are driven by the power extracted from the engine E through the PTO mechanism (not shown). Driven by hydraulic oil supplied from a hydraulic pump (not shown), the operation is performed by each operation device provided on the vehicle body 2 and the work table 30.

  In the track-and-work vehicle 1 having such a configuration, the vehicle travels on the track and moves to the destination, the boom 25 is raised, retracted, and swung to move the work table 30 to a desired height position. An operator who has boarded 30 can work on railway facilities such as an overhead track line and a trolley line. In addition, although the driving operation at the time of driving on a general road is performed in the driving cab 4, the driving operation when driving on the track can be performed from the driving cab 4 as well as from the work table 30. Yes. Below, the traveling control apparatus 50 which performs traveling control when the track-and-rail work vehicle 1 travels on a track is demonstrated with reference to FIG. 2 and FIG.

  The travel control device 50 includes a travel operation device 60 provided on the driving cab 4 and the work table 30, a hydraulic drive device 80 that drives the left and right iron wheel travel motors 13L and 13R, and a command signal input from the travel operation device 60. And a vehicle-side controller 56 that controls the engine E in response to a command signal input from an accelerator pedal 67 of the travel operation device 60. Is done.

  As shown in FIG. 2, the travel operation device 60 includes a power switch 61, a speed setting dial 62, a travel mode switch 63, a traction mode switch 64, a travel direction switch lever 66, an accelerator pedal 67, A brake pedal 68 and a parking brake operation lever 69 are provided. When the power switch 61 is turned ON, a power ON signal is input to the body part controller 55, and the traveling operation device 60 is electrically connected to the power source side so that an operation by the operator is possible. . The speed setting dial 62 is an operation means configured to be able to perform a twisting operation within a predetermined range, and outputs a maximum speed setting signal corresponding to the twisting operation position to the body part controller 55, and the body part controller 55. Is configured to set the maximum speed during orbital travel.

  The travel mode changeover switch 63 supplies hydraulic oil to the left and right iron wheel travel motors 13L and 13R in series to rotate the iron wheel travel motors 13L and 13R in rotation, and the left and right iron wheel travel motors 13L and 13R. Can be switched in a low-speed traveling mode in which the iron wheel traveling motors 13L and 13R are rotationally driven. When the traveling mode changeover switch 63 is switched, a traveling mode switching signal is input to the body part controller 55, and the body part controller 55 sets the high speed mode or the low speed mode. . The traction mode changeover switch 64 is configured to be able to be switched to a traction mode that allows the left and right iron wheel travel motors 13L, 13R to freely rotate. When the traction mode changeover switch 64 is turned ON, a traction mode change signal is input to the body part controller 55, and the traction mode is set in the body part controller 55.

  The traveling direction switching lever 66 is configured to be tiltable in the front-rear direction, and is configured to be able to switch the traveling direction during track traveling. When the traveling direction switching lever 66 is tilted forward, a forward traveling command signal is input to the body part controller 55, and the traveling direction is set to forward traveling in the body part controller 55. On the other hand, when the traveling direction switching lever 66 is tilted backward, a reverse travel command signal is input to the body part controller 55, and the traveling direction is set to reverse travel in the body part controller 55. ing.

  The accelerator pedal 67 is configured to be able to be depressed in the vertical direction, and is configured to be able to adjust a target speed during track traveling. When the accelerator pedal 67 is depressed, a target speed setting signal is input to the vehicle-side controller 56, and the target speed is set to a larger value in the vehicle-side controller 56 as the depression amount is larger. . However, the target speed set by the accelerator pedal 67 is set within a range equal to or lower than the maximum speed set by the speed setting dial 62.

  The brake pedal 68 is configured to be able to be depressed in the vertical direction, and is configured to be able to adjust the braking force during deceleration. When the brake pedal 68 is depressed, a braking command signal is input to the body part controller 55, and a greater braking force is generated by a brake device 86 described later as the amount of depression is larger. The parking brake operation lever 69 is an operation lever for operating an after-mentioned parking brake device 87 that locks the drive shafts of the iron wheel travel motors 13L and 13R so as not to rotate, and the parking brake operation lever 69 is operated. Then, a parking brake operation command signal is input to the bodywork side controller 55, and the parking brake device 87 locks or releases the rotation of the iron wheel travel motors 13L and 13R.

The travel operation device 60 provided on the work table 30 has a travel operation lever 65 configured to be tiltable in the front-rear direction instead of the accelerator pedal 67, and the travel operation lever 65 from the neutral position. The target speed can be adjusted according to the tilting operation amount.

  As shown in FIG. 3, the hydraulic drive unit 80 is configured to drive a traveling pump 81 driven by power extracted from the engine E through a PTO mechanism (not shown) and hydraulic oil discharged from the traveling pump 81. The left and right iron wheel travel motors 13L and 13R are configured to have a flow path switching valve 82 for switching between supplying in series or in parallel, and these are connected by oil paths 91 to 96 to form a hydraulic closed circuit. doing. Note that these oil passages 91 to 96 are branched from the forward-side pump oil passage 91 and the forward-side pump oil passage 91 connected to the forward-side port 81a of the traveling pump 81, and the left iron-wheel traveling motor 13L. A forward-side left motor oil passage 92 connected to the forward-side port 13La, a reverse-side left motor oil passage 93 connected to the reverse-side port 13Lb of the left iron wheel travel motor 13L, and a reverse-side pump oil passage connected to the reverse-side port 81b of the travel pump 81 94, a reverse-side right motor oil passage 95 branched from the forward-side right motor oil passage 95 and the reverse-side pump oil passage 94 connected to the forward-side port 13Ra of the right-wheel drive motor 13R and connected to the reverse-side port 13Ra of the right-wheel drive motor 13R. 96.

  The traveling pump 81 is a swash plate type variable displacement hydraulic pump, and a tilt angle control actuator 83 controls the tilt direction and tilt angle of the swash plate. The tilt angle control actuator 83 is an electromagnetic proportional control type actuator whose operation is controlled based on the operation control signal output from the body part controller 55, and controls the discharge direction and discharge amount of the traveling pump 81. Is configured to do.

  The flow path switching valve 82 is an electromagnetically controlled valve, and its operation is controlled based on an operation control signal output from the body part controller 55. The flow path switching valve 82 is switched to a lowered position as shown in FIG. 3 when in the non-excited state, and the forward drive right oil passage 95 is connected to the forward drive pump oil passage 91 and the reverse drive pump oil passage. 94, the reverse side left motor oil passage 93 is connected to supply hydraulic oil discharged from the traveling pump 81 to the left and right iron wheel traveling motors 13L and 13R in parallel. On the other hand, when the position is switched to the position where it has been excited and moved upward, the reverse side left motor oil passage 93 and the forward side right motor oil passage 95 are connected so that the hydraulic oil discharged from the traveling pump 81 travels on the left and right iron wheels. The motors 13L and 13R are configured to be supplied in series.

  Further, the hydraulic drive device 80 includes a relief valve 84 provided in a relief oil passage 97 that connects the forward-side pump oil passage 91 and the reverse-side pump oil passage 94, and on the iron wheel travel motors 13 </ b> L and 13 </ b> R side from the relief oil passage 97. The traction switching valve 100 is provided in a bypass oil passage 98 that connects the forward-side pump oil passage 91 and the reverse-side pump oil passage 94. The relief valve 84 includes a forward-side relief valve 84a that relieves hydraulic fluid to the reverse-side pump oil passage 94 when the hydraulic pressure in the forward-side pump oil passage 91 exceeds a predetermined pressure, and a hydraulic pressure in the reverse-side pump oil passage 94. A reverse-side relief valve 84b for relieving the hydraulic fluid to the forward-side pump oil passage 91 side when the pressure exceeds a predetermined pressure is configured.

The traction switching valve 100 is an electromagnetically controlled valve whose operation is controlled on the basis of an operation control signal from the body part controller 55, and closes the bypass oil passage 98 to advance the pump oil passage 91 and the reverse side. The closed state in which the flow of the hydraulic oil between the pump oil passages 94 is blocked, and the flow of the hydraulic oil between the forward pump oil passage 91 and the reverse pump oil passage 94 is permitted by opening the bypass oil passage 98. It can be switched to an open state. When the traction switching valve 100 is switched to the open state, when the flow path switching valve 82 is in a non-excited state (a state where hydraulic oil is supplied in parallel to the iron wheel traveling motors 13L, 13R), the forward movement in the iron wheel traveling motors 13L, 13R. The side ports 13La, 13Ra and the reverse side ports 13Lb, 13Rb are the reverse side left and right motor oil passages 93, 96, the reverse side pump oil passage 94, the bypass oil passage 98, the forward side pump oil passage 91 and the forward side left and right motor oil passage. 92 and 95 for communication. On the other hand, when the flow path switching valve 82 is in an excited state (a state where hydraulic oil is supplied in series to the iron wheel traveling motors 13L and 13R), the forward side port 13La and the reverse side port 13Lb of the left iron wheel traveling motor 13L are moved backward. Side left motor oil passage 93, forward side right motor oil passage 95, reverse side right motor oil passage 96, reverse side pump oil passage 94, bypass oil passage 98, forward side pump oil passage 91 and forward side left motor oil passage 92. It is designed to communicate with each other.

  Further, the hydraulic drive device 80 is configured to have a brake pump 85 that is driven by power extracted from the engine E through the PTO mechanism in the same manner as the traveling pump 81. The hydraulic oil discharged from the brake pump 85 includes four brake devices 86 provided in the vicinity of the four iron wheels 12, and parking brake devices 87 provided in the left and right iron wheel travel motors 13L and 13R, respectively. 87.

  The brake device 86 includes a cylinder 86a, a piston 86b provided in the cylinder 86a so as to be extended and retractable, a pad 86c provided at the tip of the piston 86b, and a cylinder 86a provided with the piston 86b in the storage direction. The piston spring 86d is configured to be biased. When the hydraulic oil discharged from the brake pump 85 is supplied into the cylinder chamber of the cylinder 86a through the brake oil passage 99, the piston 86b moves in the protruding direction against the urging force of the piston spring 86d, and the pad The iron wheel 12 is braked by pressing 86 c against a disk provided on the iron wheel 12.

  A brake pressure control valve 88 and a brake release valve 89 are provided in the brake pressure control oil path 111 and the brake release oil path 112 that are branched from the brake oil path 99 and connected to the oil tank T, respectively. The brake pressure control valve 88 is an electromagnetically controlled proportional valve whose operation is controlled based on an operation control signal from the body part controller 55, and the brake pressure control oil passage 111 is completely opened in a non-excited state. When excited by an operation control signal from the body part controller 55, the brake pressure control oil passage 111 is throttled according to the operation control signal. The brake pressure control valve 88 controls the hydraulic pressure supplied to the brake device 86 via the brake oil passage 99, that is, the braking force generated by the brake device 86, by restricting the brake pressure control oil passage 111 in this way. It is configured as follows. In addition, the brake pressure control valve 88 opens the brake pressure control oil passage 111 when the oil pressure in the brake oil passage 99 becomes equal to or higher than a predetermined pressure in a state where the brake pressure control oil passage 111 is completely closed. The hydraulic oil is relieved to the oil tank T.

  The brake release valve 89 is an electromagnetically controlled valve whose operation is controlled based on an operation control signal from the body part controller 55. When the brake release valve 89 is in a non-excited state, the brake release valve 89 is switched to a lowered position as shown in FIG. When the flow of hydraulic oil from the brake oil passage 99 side to the oil tank T side in the brake release oil passage 112 is cut off and switched to the position where it is excited and moved up, the brake release oil passage 112 is opened and the brake is released. The hydraulic oil in the oil passage 99 is configured to relieve to the oil tank T.

The parking brake device 87 includes a cylinder 87a, a piston 87b provided in the cylinder 87a so as to be extended and retractable, a disk 87c provided at the tip of the piston 87b, and a piston 87b provided in the cylinder 87a. And a piston spring 87d biased in the direction (rightward in FIG. 3). In the parking brake device 87, when the hydraulic oil is not supplied, the piston 87a is pushed by the piston spring 87d and moves in the extending direction, and the disc 87c is provided in a multi-plate provided inside the iron wheel travel motor 13L (13R). A brake (not shown) is pressed to lock the iron wheel drive shaft of the iron wheel travel motor 13L (13R) so as not to rotate. On the other hand, the hydraulic oil discharged from the brake pump 85 passes through the parking brake oil passages 113 and 114 branched from the brake oil passage 99, and the cylinder 87a.
The piston 87b moves in the retracted direction (leftward in FIG. 3) against the urging force of the piston spring 87d, and the disk 87c moves away from the multi-plate brake to move the iron wheel travel motor 13L (13R). ) Of the steel wheel drive shaft is unlocked.

  A parking switch valve 105 is provided between the parking brake oil passages 113 and 114. The parking switching valve 105 is an electromagnetically controlled valve whose operation is controlled based on an operation control signal from the body part controller 55, and switches to a left-moved position as shown in FIG. 3 in a non-excited state. The parking brake oil passage 114 connected to the parking brake device 87 is connected to the tank oil passage 115 connected to the oil tank T so that the operating oil is not supplied to the parking brake device 87. On the other hand, when it is switched to the position where it is excited and moved rightward, the parking brake oil passages 113 and 114 are connected and the hydraulic oil discharged from the brake pump 85 is supplied to the parking brake devices 87 and 87. ing.

  In the travel control device 50 configured as described above, when an operator who has entered the driving cab 4 operates the travel operation device 60 and travels on the track, first the parking brake operation lever 69 is operated to operate the parking brake device. The left and right iron wheel travel motors 13L, 13R are unlocked by the 87, 87. When the parking brake operation lever 69 is operated in the unlocking direction, a parking brake release signal is input to the body part controller 55, and the body part controller 55 outputs an operation control signal to the parking switching valve 105 to output the parking brake oil path. The parking switching valve 105 is switched so that 113 and 114 are connected. When the parking brake oil passages 113 and 114 are connected, the hydraulic oil discharged from the brake pump 85 is supplied to the parking brake devices 87 and 87 via the brake oil passage 99 and the parking brake oil passages 113 and 114, and the iron wheels. The locks of the iron wheel drive shafts of the travel motors 13L and 13R are released.

  Next, the traveling direction switching lever 66 is operated to set the traveling direction of the vehicle. When the traveling direction switching lever 66 is operated in the forward direction, a forward travel command signal is input to the body part controller 55, and the body part controller 55 outputs an operation control signal to the tilt angle control actuator 83 for traveling. The discharge direction of the traveling pump 81 is controlled by the tilt angle control actuator 83 so that the pump 81 discharges hydraulic fluid to the forward pump oil passage 91 side. The hydraulic oil discharged to the forward side pump oil passage 91 is supplied to the forward side ports 13La and 13Ra of the left and right iron wheel traveling motors 13L and 13R, and the iron wheel traveling motors 13L and 13R are rotationally driven in the forward direction. That is, the iron wheels 12 and 12 are rotationally driven in the forward direction by the iron wheel traveling motors 13L and 13R, and the vehicle travels forward.

  On the other hand, when the traveling direction switching lever 66 is operated in the reverse direction, a reverse travel command signal is input to the body part controller 55, and the body part controller 55 outputs an operation control signal to the tilt angle control actuator 83. The discharge direction of the travel pump 81 is controlled by the tilt angle control actuator 83 so that the travel pump 81 discharges hydraulic oil to the reverse pump oil passage 94 side. The hydraulic fluid discharged to the reverse pump oil passage 94 is supplied to the reverse ports 13Lb and 13Rb of the left and right iron wheel travel motors 13L and 13R, and the iron wheel travel motors 13L and 13R are rotationally driven in the reverse direction. That is, the iron wheels 12 and 12 are rotationally driven in the reverse direction by the iron wheel traveling motors 13L and 13R, and the vehicle travels backward.

The traveling speed of the vehicle is controlled by changing the depression amount of the accelerator pedal 67. When the accelerator pedal 67 is depressed, a speed command signal corresponding to the depression amount is input to the vehicle-side controller 56, and the vehicle-side controller 56 rotates the engine E so that the number of rotations corresponds to the depression amount of the accelerator pedal 67. Control the number. That is, by changing the amount of depression of the accelerator pedal 67 and changing the number of revolutions of the engine E, the operation discharged from the traveling pump 81 driven by the engine E and supplied to the iron wheel traveling motors 13L and 13R. The amount of oil is changed, whereby the traveling speed of the vehicle is controlled. However, at this time, the traveling speed of the vehicle controlled in accordance with the depression amount of the accelerator pedal 67 is controlled within a range equal to or lower than the maximum speed set by the speed setting dial 62.

  Thus, when traveling on the track, the high-speed traveling mode and the low-speed traveling mode can be switched by the traveling mode switch 63. When the travel mode switch 63 is switched to the low speed travel mode, the low speed travel mode switching signal is input to the body part controller 55, and the body part controller 55 outputs the operation control signal to the flow path switching valve 82. Without connecting the flow path switching valve 82 to the non-excited state, the forward drive pump oil passage 91 and the forward drive right motor oil passage 95 are connected, and the reverse drive left motor oil passage 93 and the reverse drive pump oil passage 94 are connected. The flow path switching valve 82 is switched so that When the flow path switching valve 82 is thus switched, the hydraulic oil discharged from the traveling pump 81 is supplied in parallel to the left and right iron wheel traveling motors 13L, 13R, and the iron wheel traveling motors 13L, 13R are driven at high torque and low speed. Thus, the vehicle is driven at a high torque and low speed.

  On the other hand, when the traveling mode changeover switch 63 is switched to the high speed traveling mode, a high speed traveling mode switching signal is input to the body part controller 55, and the body part controller 55 sends an operation control signal to the flow path switching valve 82. The flow path switching valve 82 is switched so that the reverse drive left motor oil passage 93 and the forward drive right motor oil passage 95 are connected. When the flow path switching valve 82 is switched in this way, the hydraulic oil discharged from the traveling pump 81 is supplied in series to the left and right iron wheel traveling motors 13L and 13R, and the iron wheel traveling motors 13L and 13R are driven at low torque and high speed. Thus, the vehicle is driven at a low torque and a high speed.

  When traveling on the track as described above, the traction mode changeover switch 64 is turned OFF (the traction traveling mode is not set), and the bypass oil passage 98 is closed by the traction switching valve 100 to move forward. The hydraulic oil flow between the side pump oil passage 91 and the reverse side pump oil passage 94 is blocked.

  In order to decelerate and stop the vehicle traveling on the track, the brake pedal 68 is operated to brake each iron wheel 12. When the brake pedal 68 is depressed, a braking command signal corresponding to the depression amount is input to the body part controller 55, and the body part controller 55 outputs an operation control signal to the tilt angle control actuator 83. Then, the discharge amount of the traveling pump 81 is controlled so that the discharge amount of the traveling pump 81 becomes zero, and the supply of hydraulic oil to the left and right iron wheel traveling motors 13L, 13R is stopped. As a result, the engine braking force EB caused by the rotational resistance of the traveling pump 81 and the engine E is applied to the left and right iron wheel traveling motors 13L and 13R (see, for example, FIG. 4). Further, the body part controller 55 outputs an operation control signal to the brake pressure control valve 88 and controls the brake pressure control oil path 111 to be narrowed by the brake pressure control valve 88 according to the depression amount of the brake pedal 68. . With this control, the hydraulic pressure supplied to each brake device 86 via the brake oil passage 99, that is, the braking force generated by each brake device 86 is controlled according to the depression amount of the brake pedal 68, and the four brake devices 86 are controlled. Thus, a braking force MB (hereinafter referred to as a braking brake force MB) corresponding to the depression amount of the brake pedal 68 is generated (see, for example, FIG. 4). Each of the iron wheels 12 is braked by the engine braking force EB and the braking brake force MB generated in this way, and the vehicle is decelerated and stopped.

When the vehicle stops, the parking brake operation lever 69 is operated to lock the iron wheel drive shafts of the left and right iron wheel travel motors 13L, 13R by the parking brake devices 87, 87. When the parking brake operation lever 69 is operated in the locking direction, a parking brake operation signal is input to the body part controller 55, and the body part controller 55 outputs the operation control signal output to the parking switch valve 105. The parking switch valve 105 is switched so that the parking brake oil passage 114 and the tank oil passage 115 connected to the parking brake devices 87 and 87 are connected to each other. When the parking brake oil passage 114 and the tank oil passage 115 are connected, the operating oil pressure supplied to the parking brake devices 87 and 87 is lowered, and the pistons 87a and 87a are pushed by the piston springs 87d and 87d and are extended. The discs 87c and 87c press a multi-plate brake (not shown) provided inside the iron wheel travel motors 13L and 13R so that the iron wheel drive shafts of the iron wheel travel motors 13L and 13R do not rotate. Locked.

  The body part controller 55 stops the output of the operation control signal output to the brake pressure control valve 88 to open the brake pressure control oil passage 111 and outputs the operation control signal to the brake release valve 89. Then, the brake release valve 89 is switched so as to open the brake release oil passage 112. When the brake pressure control oil passage 111 and the brake release oil passage 112 are opened, the hydraulic pressure supplied to each brake device 86 is lowered, and the braking of the iron wheel 12 by each brake device 86 is released. The output of the operation control signal to the brake release valve 89 is stopped after a lapse of a predetermined time, and the brake release oil passage 112 is closed by the brake release valve 89.

  In the track-and-rail work vehicle 1, the left and right iron wheel travel motors 13 </ b> L and 13 </ b> R are driven to rotate on the track as described above, and connected to another vehicle and pulled by the vehicle to travel on the track. There is a case. Even when the vehicle is towed, first, the parking brake operation lever 69 is operated to unlock the iron wheel drive shafts of the left and right iron wheel traveling motors 13L, 13R by the parking brake devices 87, 87.

  Then, the traction mode changeover switch 64 is operated to switch to the traction mode. When the traction mode changeover switch 64 is switched to the traction mode, a traction mode switching signal is input to the body part controller 55, and the body part controller 55 outputs an operation control signal to the traction switching valve 100 to bypass it. The traction switching valve 100 is switched to an open state so that hydraulic fluid flows between the forward pump oil passage 91 and the reverse pump oil passage 94 via the oil passage 98. When the traction switching valve 100 is switched in this way, when the flow path switching valve 82 is in a non-excited state, the forward-side ports 13La and 13Ra and the reverse-side ports 13Lb and 13Rb in the iron wheel travel motors 13L and 13R The motor oil passages 93 and 96, the reverse drive pump oil passage 94, the bypass oil passage 98, the forward drive pump oil passage 91, and the forward drive left and right motor oil passages 92 and 95 are communicated. Because of this communication, both the left and right iron wheel travel motors 13L and 13R (iron wheels 12 and 12) can freely rotate and are pulled by another vehicle to cause the track work vehicle 1 to be driven.

  When the traction switching valve 100 is switched to the open state and the flow path switching valve 82 is in an excited state, the forward side port 13La and the reverse side port 13Lb of the left iron wheel travel motor 13L are connected to the reverse side left side. Via a motor oil passage 93, a forward side right motor oil passage 95, a reverse side right motor oil passage 96, a reverse side pump oil passage 94, a bypass oil passage 98, a forward side pump oil passage 91 and a forward side left motor oil passage 92. Communicated. Even in this case, both the left and right iron wheel travel motors 13L, 13R (iron wheels 12, 12) can freely rotate.

  As described above, when the other vehicle and the track-and-work vehicle 1 are decelerated and stopped when the vehicle is towed by another vehicle, the braking distance is increased only by the braking force generated in the other vehicle. For this reason, it is also recommended that the operator gets on the driving cab 4 in the railroad work vehicle 1, and the operator operates the travel operation device 60 to generate the braking brake force by the brake devices 86. In the track-and-rail work vehicle 1, in order to operate each brake device 86, the engine E and the brake pump 85 are driven even when the vehicle is towed.

  When the brake pedal 68 is depressed in the track-and-rail work vehicle 1 that is towed by another vehicle, a braking command signal corresponding to the amount of depression is applied in the same manner as when the iron wheel traveling motors 13L and 13R are driven to rotate. Is input to the body part controller 55. At this time, the traction mode switching signal is input to the body part controller 55, and the traction mode is set. Since the bypass oil passage 98 is opened as described above when the track-and-rail work vehicle 1 is towed, the traveling pump 81 and the rotational resistance of the engine E with respect to the left and right iron wheel traveling motors 13L and 13R are used. The engine braking force EB hardly acts. Therefore, when the towing travel mode is set, the bodywork side controller 55 performs control to increase the braking brake force MB generated by the four brake devices 86 by the amount that the engine braking force EB decreases and becomes insufficient. Do. That is, the body part controller 55 controls the throttle amount of the brake pressure control oil path 111 by the brake pressure control valve 88, and the traction braking brake force MB ′ (≧ engine braking force EB + braking brake) by the four brake devices 86. Force MB) is generated (see, for example, FIG. 5). Each iron wheel 12 is braked by the traction braking brake force MB ′ generated in this way, and the track work vehicle 1 is decelerated and stopped together with other vehicles.

  When the track-and-work vehicle 1 stops, the parking brake operating lever 69 is operated to lock the iron wheel drive shafts of the left and right iron wheel travel motors 13L and 13R by the parking brake devices 87 and 87, as in the above case. The output of the operation control signal output to the brake pressure control valve 88 by the controller 55 is stopped, and the braking of the iron wheel 12 by each brake device 86 is released.

  As described above, according to the track-and-rail work vehicle 1, when the traction mode is switched to the traction mode by the traction mode changeover switch 64 (the traction mode is set) and the vehicle is towed by another vehicle, the traveling pump 81 and the engine E Control is performed to increase the braking brake force MB generated by the four brake devices 86 so that the engine braking force EB due to the rotational resistance or the like no longer acts on the braking brake MB. Each wheel 12 is braked by a brake force MB ′ (≧ engine brake force EB + brake brake force MB), and the track work vehicle 1 is decelerated and stopped together with other vehicles. Therefore, the braking distance becomes longer when the left and right iron wheel travel motors 13L and 13R (iron wheels 12 and 12) are switched to allow free rotation for towing and the engine braking force EB no longer acts. Can be prevented.

  Although the embodiment according to the present invention has been described so far, the scope of the present invention is not limited to that shown in the above-described embodiment. For example, in the above-described embodiment, the traction switching valve 100 is an electromagnetically controlled valve that is controlled based on an operation control signal from the body part controller 55, but the traction switching valve 100 is manually operated by an operator. You may comprise so that the bypass oil path 98 may be opened and closed. When the traction switching valve 100 is configured in this way, the opening / closing of the traction switching valve 100 is detected by a detector such as a limit switch, and the traction mode is set in the bodywork side controller 55 based on the detection signal. It is preferable to configure as described above.

In the above-described embodiment, the left and right iron wheels 12 and 12 are rotationally driven by hydraulic motors (iron wheel traveling motors 13L and 13R). However, the left and right iron wheels 12 and 12 are rotationally driven by an electric motor. Also good. In the case where the iron wheels 12 and 12 are driven to rotate by the electric motor, the electric motor can be freely rotated without supplying electric power to the electric motor, and when the vehicle is towed by another vehicle, regeneration by the electric motor is performed. Almost no braking force is generated. Therefore, similarly to the above-described embodiment, the control is performed to increase the braking brake force MB generated by the four brake devices 86 so that the regenerative braking force does not act, and the traction braking brake increased more than the braking brake MB. It is preferable that each iron wheel 12 is braked by the force MB ″ (≧ regenerative braking force + braking braking force MB).

  In the above-described embodiment, when the left and right iron wheel travel motors 13L and 13R are unlocked by the parking brake devices 87 and 87, the hydraulic oil discharged from the brake pump 85 is supplied to the brake oil passage 99 and the parking switching valve. 105 and the parking brake oil passages 113 and 114 are supplied to the parking brake devices 87 and 87 to unlock the iron wheel travel motors 13L and 13R. In the parking brake devices 87 and 87, the piston 87b is replaced with a piston. An unlocking bolt that can be moved in the retracting direction against the urging force of the spring 87d is provided, and the unlocking bolt is manually operated by the operator, so that the iron wheel traveling motor 13L by the parking brake devices 87, 87 is provided. , 13R may be unlocked.

  Moreover, although the above-mentioned embodiment demonstrated the railroad working vehicle as an example of the vehicle provided with the braking device according to the present invention, the present invention is not necessarily a roadway working vehicle configured to be capable of both road traveling and track traveling. There is no need, and it is possible to apply even a vehicle that can only travel on the road or a vehicle that can only travel on the track.

1 Railroad work vehicle 2 Car body 12 Iron wheel (wheel)
13L, 13R Iron-wheel travel motor (wheel drive means)
55 Controller (brake control device)
68 Brake pedal (brake operating means)
80 Hydraulic drive device (wheel drive means)
86 Brake device 100 Traction switching valve

Claims (1)

A vehicle body having wheels and capable of traveling;
Wheel driving means for rotationally driving the wheels;
A braking device that applies braking force to the wheels;
Brake operating means for operating the brake device;
A brake control device that operates the brake device in response to an operation of the brake operation means, and applies a braking force according to an operation amount of the brake operation means to the wheel by the brake device to perform braking control on the wheel; With
The wheel driving means is configured to be switchable to allow free rotation of the wheel,
The brake control device includes:
When the brake operating means is operated while the wheel is driven by the wheel driving means, the braking force is applied by the brake device together with the engine braking action caused by the rotational resistance of the wheel driving means. Giving control to the wheel to brake the wheel,
When the brake operating means is operated when the wheel driving means is switched to allow free rotation of the wheel and the brake operating means is operated, the brake device is configured to prevent the engine braking action from acting on the wheel. A braking device for a vehicle, wherein control is performed to increase the braking force applied to the wheel, and control is performed to apply the increased braking force to the wheel to brake the wheel.

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