JP3361792B2 - Towing vehicle - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a towing vehicle.

[0002]

2. Description of the Related Art In a towing vehicle in which a tractor and a trailer are connected by a kingpin coupler so that the trailer is towed by the tractor, as shown in FIG. 13, conventionally, as shown in FIG. And a differential portion 5 connected between the left and right rear wheels 4 of the tractor 1 and a differential portion 8 connected between the left and right rear wheels 7 of the trailer 6, respectively.
10, the hydraulic pump 3 and the hydraulic motors 9 for driving,
10 to hydraulic pipes 11 and 12 and hydraulic hoses 13 to 1
Some are connected in parallel through 5. Further, as shown in FIG. 14, the driving hydraulic motors 9 and 10 are attached to the left and right rear wheels 4 of the tractor 1 and the left and right rear wheels 7 of the trailer 6, respectively, so that the left and right rear wheels 4 and 7 are independent. I also tried to drive it.

With such a structure, when the hydraulic pump 3 is driven by the engine 2, the hydraulic pump 3 is driven from the hydraulic pump 3 to the driving hydraulic motors 9 and 10 via the hydraulic hoses 13 to 15 and the hydraulic pipes 11 and 12, respectively. Pressure oil is supplied and the driving hydraulic motors 9 and 10 are individually driven to generate a required driving force on the rear wheels 4 of the tractor 1 and the rear wheels 7 of the trailer 6.

[0004]

However, in such a conventional towing vehicle, the driving hydraulic motors 9 and 10 are driven by the direct power of the engine 2, so that the tractor 1 and the trailer 6 are connected to each other. A complicated interlocking drive mechanism was required to interlock the spaces. Further, since it is connected to the engine 2 in a direct-acting manner, the hydraulic pump 3 and the driving hydraulic motors 9 and 1 can be operated during an overrun.
There was a risk of damage to hydraulic equipment such as 0. Further, the hydraulic pump 3 and the driving hydraulic motors 9 and 1 are used even when the vehicle is stopped.
Since pressure oil is supplied to hydraulic equipment such as 0, engine 2
Was overloaded.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to solve the above problems and provide a towing vehicle capable of obtaining stable running by linking a tractor and a trailer without requiring a complicated mechanism. It is in.

[0006]

In order to solve the above-mentioned problems, in the invention described in claim 1, the vehicle is connected to a towing vehicle which is driven by an engine to drive rear wheels and is self-propelled. In a towing vehicle in which the vehicle is towably connected, a hydraulic actuator is attached to the rear wheel of the towing vehicle, and a hydraulic actuator is attached to the rear wheel of the trailing vehicle so that the two hydraulic actuators are connected in series with a loop hydraulic circuit. It is characterized by being connected.

According to the invention according to claim 1 having such a configuration, the hydraulic actuator connected to the rear wheel portion of the towing vehicle and the hydraulic actuator connected to the rear wheel portion of the trailer vehicle are looped hydraulic circuits. By connecting in series with the rear wheel of the towing vehicle, the rear wheel of the towing vehicle and the rear wheel of the trailing vehicle can be interlocked without using a complicated interlocking drive mechanism. Moreover, since the hydraulic actuator is not connected to the engine in a direct-acting manner, there is less risk of damage to hydraulic equipment such as the hydraulic actuator during overruns. Further, since the hydraulic actuator is in a stopped state when traveling is stopped, the engine is not burdened. The hydraulic actuator is tuned and controlled according to the traveling states of the towing vehicle and the trailing vehicle. Further, since the engine is not directly connected to the engine, hydraulic components can be made compact. When traveling on a flat ground, the four-wheel full-time traveling state can be achieved by the hydraulic actuators provided on the towing vehicle side and the trailing vehicle side, respectively.

According to the second aspect of the present invention, the loop-shaped hydraulic circuit is connected with a return passage for releasing excess hydraulic fluid and a replenishment passage for replenishing insufficient hydraulic fluid. It has a feature.

According to the second aspect of the present invention thus configured, the loop-shaped hydraulic circuit is provided with a return passage for releasing excess hydraulic oil and a replenishment passage for replenishing insufficient hydraulic oil. Since the and are connected, the synchronized operation of the rear wheel of the towing vehicle and the rear wheel of the trailing vehicle is maintained during turning, and the turning traveling of the towing vehicle is stabilized.

The invention described in claim 3 is characterized in that the loop-shaped hydraulic circuit is connected to a flow rate regulating means for regulating the flow rate of the working oil.

According to the third aspect of the present invention having the above-mentioned structure, the loop-shaped hydraulic circuit is connected to the flow rate regulating means for regulating the flow rate of the hydraulic oil, whereby the engine brake, the retarder brake, and the like. Since the rear wheels of the towing vehicle and the rear wheels of the trailing vehicle operate simultaneously during the deceleration state due to the auxiliary brake or the like, the towing vehicle can perform stable deceleration. In addition, when traveling downhill, the rear wheels of the towing vehicle and the trailing wheels of the trailing vehicle are simultaneously in the same deceleration state, and the rear-end collision load generated in the vehicle body coupling device provided on the towing vehicle side is mitigated to prevent the jack knife phenomenon. Can be prevented.

According to a fourth aspect of the invention, the loop-shaped hydraulic circuit is connected with actuator rotation restraining means for restraining rotation of the hydraulic actuator in parallel with each hydraulic actuator.

According to the invention according to claim 4 configured as described above, since the overall load moves rearward when the vehicle starts uphill, no load is applied to the axle of the towing vehicle,
The rear wheels may slip and make it impossible to start, but by activating the actuator rotation restraint means, the tuning / control function of the hydraulic actuator works, and the hydraulic actuator on the side of the trailing vehicle exerts the driving force and jumping. It is possible to eliminate the slippage of the rear wheels due to the phenomenon and facilitate starting. Further, when a slip phenomenon occurs during traveling on a bad road or a snowy road, the actuator rotation restraining means is actuated to slip the axles 28, 34 on the slipping side.
It is possible to recover the driving force by driving the other axles 34, 28 by utilizing the rotation of the.

The invention described in claim 5 is characterized in that a hydraulic connection mechanism is provided which is capable of separately connecting the loop hydraulic circuit to the tow vehicle hydraulic circuit and the auxiliary vehicle hydraulic circuit.

According to the fifth aspect of the present invention configured as described above, a hydraulic connection mechanism is provided which can separate and connect the loop hydraulic circuit to the tow vehicle hydraulic circuit and the auxiliary vehicle hydraulic circuit. Therefore, it is possible to easily connect and disconnect the towing vehicle and the trailing vehicle.

The invention described in claim 6 is characterized in that hydraulic free means is connected in parallel with each hydraulic actuator to the loop hydraulic circuit.

According to the sixth aspect of the present invention configured as described above, since the hydraulic free means is connected in parallel to each hydraulic actuator to the loop hydraulic circuit, the towing vehicle can be operated independently or the towing vehicle can be operated independently. It is possible to operate the vehicle and the accompanying vehicle in combination with other vehicles.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Specific embodiments of the present invention will be described below with reference to the drawings.

1 to 12 show an embodiment of the present invention.

First, the structure will be described. In the towing vehicle of this embodiment, a trailer 21 or other trailing vehicle is a kingpin coupler device 22 or the like, while a trailer 21 or other trailing vehicle is a self-propelled vehicle such as a tractor 20 that can be driven by an engine. It is detachably connected using a vehicle body connecting device.

The tractor 20 has a driver's seat 24 on the upper side of the front of the chassis 23 and a connecting portion of the kingpin coupler device 22 on the upper side of the rear of the chassis 23. Further, front and rear steerable front and rear wheels 25 are provided on the lower surface side of the front portion of the chassis 23, and left and right rear wheels capable of generating driving force are provided on the lower surface side of the rear portion of the chassis 23 and behind the kingpin coupler device 22. Wheels 26 (mechanical drive wheels) are provided. The rear wheel 26 is connected to both ends of an axle 28 having a differential portion 27,
The driving force of the engine 37 (see FIG. 5) provided on the tractor 20 is transmitted to the transmission mechanism (not shown) and the propeller shaft 2
9, a differential portion 27, an axle 28 and other mechanical drive mechanisms 30 are used for transmission.

Further, the trailer 21 has a cargo bed portion 31.
And the left and right rear wheels 32 provided at the rear of the loading platform 31
(Mechanical driven wheel). The rear wheel 32 is connected to both ends of an axle 34 having a differential portion 33. This trailer 21 is provided with a connecting portion of a kingpin coupler device 22 on the lower surface side of the front portion, and the tractor 2
When connected to 0, the rear wheel 26 of the tractor 20 can be used as its front wheel.

Then, as shown in FIG.
A hydraulic actuator such as a hydraulic pump / motor 35 is mounted on the rear portion of the differential portion 27 of the mounting bracket 3
It is attached via 8. The hydraulic pump / motor 35 is connected to a rear end portion of the input / output shaft 40 of the differential portion 27 connected to the propeller shaft 29 via a universal joint 39 via a companion flange 41, a coupling joint 42 and the like. There is. The companion flange 41 and the coupling joint 42 are housed in the mounting bracket 38.

Similarly, as shown in FIG.
A hydraulic actuator such as a hydraulic pump / motor 36 is attached to the front of the differential portion 33 of the mounting bracket 4
It is attached via 3. The hydraulic pump / motor 35 is connected to the front end portion of the input / output shaft 144 of the differential portion 33 via a companion flange 145, a coupling joint 146, and the like. The companion flange 145 and the coupling joint 146 are housed in the mounting bracket 43.

A hydraulic oil tank 44 is provided behind the driver's seat 24 of the chassis 23 of the tractor 20. As shown in FIG. 5, the hydraulic pressure is provided between the two connecting ends 44 a, 44 b provided in the hydraulic oil tank 44 and the two ports 35 a, 35 b of the hydraulic pump / motor 35 of the tractor 20. A loop-shaped hydraulic circuit 47 on the towing vehicle side is connected by pipes 45a and 45b and hydraulic hoses 46a and 46b.

Suction filters 48a and 48b are provided at the connection ends 44a and 44b of the hydraulic pipes 45a and 45b with the hydraulic oil tank 44, respectively. The suction filters 48 a and 48 b are housed in the hydraulic oil tank 44.

Further, in-line check valves 49a and 49b capable of flowing pressure oil only in one direction from the hydraulic oil tank 44 side to the hydraulic pump / motor 35 side are provided near the hydraulic oil tank 44 of the hydraulic pipes 45a and 45b. Each is provided. The tow vehicle hydraulic circuit 47 is functionally connected to the in-line check valves 49a, 49a from the hydraulic oil tank 44.
It is roughly divided into a replenishment flow passage 47a for replenishing hydraulic oil to the hydraulic pump / motor 35 via b and a circulation flow passage 47b to circulate the hydraulic oil using the hydraulic pump / motor 35.

A hydraulic free means such as an unloader valve 50 is connected to the migratory flow path 47b in parallel with the hydraulic pump / motor 35 through a flow path 45c. Further, a flow passage 45d in which an actuator rotation inhibiting means such as a relief valve 51 and a stop valve 52 are connected in series is connected in parallel with the hydraulic pump / motor 35. The unloader valve 50 is a normally closed valve, and the stop valve 52 is a normally open valve.

Further, the migratory flow path 47b and the hydraulic oil tank 44
Between the relief valve 53 and the return filter 5
And a return flow channel 55 having a number of 4 are connected.

From the towing vehicle side hydraulic circuit 47, flexible connecting ends 56a and 56b such as hydraulic hoses are provided.
Are branched so as to form a part of the migratory flow path 47b. Among these, a flow rate regulating means such as a retarder valve 57 for regulating the flow rate of the hydraulic oil is provided at the connecting portion between the connecting end 56b and the migratory flow path 47b of the tow vehicle-side hydraulic circuit 47.

On the other hand, a pair of joint portions 60a and 60b such as hydraulic couplers to which the terminal portions of the connecting ends 56a and 56b can be attached and detached are provided at the front end portion of the cargo bed portion 31 of the trailer 21. Then, the coupling end 56 on the tractor 20 side
a, 56b and the joint portions 60a, 6 on the trailer 21 side
0b constitutes a hydraulic connection mechanism 58.

The joint portions 60a and 60b and the two ports 36 of the hydraulic pump / motor 36 of the trailer 21.
Hydraulic hoses 61a and 61b are provided between a and 36b, respectively.
The auxiliary vehicle side hydraulic circuit 63 is connected by b, hydraulic pipes 62a, 62b, and the like. Then, the connecting ends 56a, 56
When b and the joint portions 60a and 60b are connected, the hydraulic pump / motors 35 and 36 are connected in series to a loop-shaped hydraulic circuit (the migratory flow passage 47b of the towing vehicle-side hydraulic circuit 47 and the associated vehicle-side hydraulic circuit 63). As a result, the hydraulic oil is circulated. Note that, for example, the rear wheel 2 of the tractor 20
When both 6 and the rear wheel 32 of the trailer 21 are rotating in the forward direction, the working oil discharged from the hydraulic pump / motors 35, 36 circulates in the same direction in the loop hydraulic circuit.
The discharge directions of the hydraulic pump / motor 35 and 36 are set in advance.

A hydraulic free means such as an unloader valve 64 is connected to the hydraulic circuit 63 on the vehicle side in parallel with the hydraulic pump / motor 36 through a flow path 62c. In addition, a flow path 62d in which an actuator rotation suppressing means such as a relief valve 65 and a stop valve 66 is connected in series.
Are connected in parallel with the hydraulic pump / motor 36. The unloader valve 64 is a normally closed valve, and the stop valve 6
6 is a normally open valve.

The electric circuit wire harness 67 extending from the control switch box 68 provided in the driver's seat 24 is connected to the retarder valve 57 and the stop valve 52,
It is connected to 66. This control switch box 6
8 is provided with operation switches such as a retarder brake switch 69, a front wheel slip stop switch 70, and a rear wheel slip stop switch 71.

Next, the operation of this embodiment will be described.

The towing vehicle such as the tractor 20 is the engine 3
7, a transmission mechanism (not shown), a propeller shaft 2
By transmitting the driving force to the rear wheel 26 via the mechanical driving mechanism 30 such as 9, the differential portion 27, the axle 28, etc., the vehicle can be independently driven by the driving force of the engine 37. Further, the tractor 20 can steer the left and right front wheels 25 to change the direction.

The trailer 21 and the like are mechanically connected to the tractor 20 by a vehicle body connecting device such as a kingpin coupler device 22 so that the trailer 21 is towed through the kingpin coupler device 22. You can

In this embodiment, when connecting the tractor 20 and the trailer 21, the connecting end 56 on the tractor 20 side is connected.
a, 56b and the joint portions 60a, 6 on the trailer 21 side
0b, and the hydraulic pumps / motors 35 and 36 form a loop hydraulic circuit (the migratory flow path 4 of the tow vehicle-side hydraulic circuit 47).
7b and the hydraulic circuit 63 on the trailing vehicle side are connected in series.

Then, the hydraulic pump / motor 3 corresponding to the rotation of the rear wheel 26 (mechanical drive wheel) of the tractor 20.
5 is driven, and the hydraulic fluid discharged from the hydraulic pump / motor 35 flows into the loop hydraulic circuit. Similarly,
The corresponding hydraulic pump / motor 36 is driven by the rotation of the rear wheel 32 (mechanical driven wheel) of the trailer 21, and the hydraulic fluid discharged from the hydraulic pump / motor 36 flows into a loop hydraulic circuit. As a result, the hydraulic pump / motor 35 on the tractor 20 side and the hydraulic pump / motor 36 on the trailer 21 side are hydraulically linked, and the rear wheel 26 of the tractor 20 and the rear wheel 32 of the trailer 21 are hydraulically linked. Become so. Then, hydraulic drive force is applied (generated / transmitted) to the rear wheel 32 of the trailer 21.

That is, as shown in FIG. 6, when the tractor 20 travels straight on a flat ground with the trailer 21 connected, the hydraulic oil generated in the hydraulic pump / motor 35 by the rotation of the rear wheel 26 of the tractor 20. Since the oil amount and the flow direction of the hydraulic oil are equal to the oil amount and the flow direction of the hydraulic oil generated in the hydraulic pump / motor 36 by the rotation of the rear wheel 32 of the trailer 21, the migratory flow path 47b of the tow vehicle-side hydraulic circuit 47b. Also, the hydraulic pump / motors 35, 36 are synchronously operated by the hydraulic oil that circulates between the hydraulic pump / motors 35, 36 via the hydraulic circuit 63 on the side of the associated vehicle, and the rear wheels 26, 32
Rotate substantially equivalently, and the rear wheels 26 of the tractor 20 and the rear wheels 32 of the trailer 21 become a four-wheel full-time traveling state, and the traveling of the towing vehicle is stabilized. At this time, since the hydraulic pump / motors 35 and 36 are in a no-load state, the running resistance generated in the hydraulic system is small. In addition,
Specifically, the hydraulic oil is the hydraulic pump / motor 35, the hydraulic hose 46a, the migratory flow path 47b portion of the hydraulic pipe 45a, the connecting end 56a, the hydraulic pipe 62a, the hydraulic hose 61a, the hydraulic pump / motor 36, the hydraulic hose 61b, Hydraulic piping 62
b, the connection end 56b, the portion of the hydraulic flow passage 47b of the hydraulic pipe 45b, the hydraulic hose 46b, and the hydraulic pump / motor 35 are circulated in this order.

As shown in FIG. 7, when the towing vehicle moves backward, the axle 28 of the rear wheel 26 of the tractor 20 and the trailer 2 are pulled.
Since the rotation of the rear wheel 32 of the first axle 32 is reversed, the flow of hydraulic oil that circulates between the hydraulic pump / motors 35 and 36 is in the opposite direction. Other than that, it becomes almost the same as the above.

As shown in FIG. 8, when the towing vehicle turns, the number of rotations of the rear wheel 26 of the tractor 20 and the trailer 21 are increased.
Since the rotation speed of the rear wheel 32 is different, the amount of hydraulic oil sucked and discharged by the hydraulic pump / motor 35 on the tractor 20 side and the hydraulic oil sucked / discharged by the hydraulic pump / motor 36 on the trailer 21 side. Difference occurs (normally, the suction / intake of the hydraulic pump / motor 35 on the tractor 20 side).
The discharge amount is larger). Then, the surplus hydraulic oil starts to circulate through the flow passage 45d, and the relief valve 53 operates so that the surplus hydraulic oil is discharged from the discharge side of the hydraulic pump / motor 35 through the return filter 54 and the return flow passage 55. Of the hydraulic oil is returned to the hydraulic oil tank 44. Also,
The in-line check valve 49b operates to supply a shortage of hydraulic oil from the hydraulic oil tank 44 to the suction side of the hydraulic pump / motor 35. As a result, the synchronized operation of the hydraulic pump / motors 35 and 36 is maintained, and the turning traveling of the towing vehicle is stabilized.

As shown in FIG. 9, when the towing vehicle is traveling downhill, the retarder brake switch 69 of the control switch box 68 provided in the driver's seat 24 is operated,
The retarder valve 57 is operated. Then, the operation of the retarder valve 57 causes the hydraulic pump / motors 35 and 36 to operate.
Since the flow rate of the hydraulic oil that circulates between the hydraulic pumps and motors 35 and 36 is regulated, the rear wheels 26 and 32 are both decelerated and braked. This allows
The rear-end collision load generated in the kingpin coupler device 22 portion is alleviated, and stable traveling is possible. For example, since the weight of the tractor 20 and the trailer 21 and the load such as a load move forward when the towing vehicle travels downhill, if the vehicle is decelerated by an auxiliary brake or a foot brake in this state, the vehicle will travel. May become unstable and the jack knife phenomenon may occur, but in the present embodiment, the occurrence of the jack knife phenomenon can be prevented.

As shown in FIG. 10, when the towing vehicle starts uphill, the weight of the tractor 20 and the trailer 21 and the load such as the load move to the rear, so that the tractor 20 moves.
The load is not applied to the rear wheel 26, and the rear wheel 26 may slip. When the rear wheel 26 of the tractor 20 to which the driving force of the engine 37 is transmitted runs idle, the hydraulic pump / motor 3
5 rotates at a high speed, sucks a large amount of hydraulic oil from the hydraulic oil tank 44 through the in-line check valve 49b, and discharges a large amount of high-pressure hydraulic oil. At this time, the front wheel slip stop switch 70 of the control switch box 68 provided in the driver's seat 24 is operated to operate the stop valve 52 to close the flow path 45d. Then, a large amount of high-pressure hydraulic oil discharged by the hydraulic pump / motor 35 flows through the flow path 45d.
Can not escape to the hydraulic pump and motor 3
Since a large amount of high-pressure hydraulic oil discharged from No. 5 is forcibly sent to the hydraulic pump / motor 36, the hydraulic pump / motor 36 is driven to generate a driving force on the rear wheel 32 of the trailer 21. Thereby, the rear wheel 2 of the tractor 20
It is possible to assist the inability to pull by using the kingpin coupler device 22 due to the idling of 6. It should be noted that this state is instantaneous, and the circuit state during normal running is immediately restored. Further, the driving force of the engine 37 is transmitted to the hydraulic pump / motor 36 via the hydraulic system, so that the tractor 20
The idling of the rear wheel 26 and the hydraulic pump / motor 35 is suppressed.

As shown in FIG. 11, the towing vehicle is on a rough road.
When a slip phenomenon occurs on a snowy road, for example, when the rear wheel 26 of the tractor 20 slips and slips, a large amount of high-pressure hydraulic oil generated by the hydraulic pump / motor 35 is used as in the case of FIG. The pump / motor 36 is operated. At this time, a difference occurs in the amount of hydraulic oil discharged due to the difference in rotation between the hydraulic pump / motors 35 and 36. Then, the relief valve 53 operates and the return filter 5
4 and the return flow path 55, the hydraulic pump / motor 35
Excess hydraulic oil is returned to the hydraulic oil tank 44 from the discharge side. In addition, in-line check valves 49a and 49b
Is activated to operate the hydraulic pump / motor 3 from the hydraulic oil tank 44.
A shortage of hydraulic oil is supplied to the suction side of No. 5. In this state, the control switch box 6 provided in the driver's seat 24
The front wheel slip stop switch 70 of No. 8 is operated to operate the stop valve 52 to close the flow path 45d. Then, a large amount of high-pressure hydraulic oil discharged by the hydraulic pump / motor 35 cannot escape to the flow path 45d, and a large amount of high-pressure hydraulic oil discharged from the hydraulic pump / motor 35 is forcibly forced. The hydraulic pump / motor 36 can be driven. When the rear wheel 32 of the trailer 21 idles, the rear wheel slip stop switch 71 of the control switch box 68 provided in the driver's seat 24 is operated to operate the stop valve 66.

Then, as shown in FIG. 12, the tractor 2
0 and the trailer 21 are separated, the joint ends 56a and 56b of the tractor 20 and the joint portion 60 of the trailer 21 are separated.
Separate a and 60b. When traveling the tractor 20 in this state, the unloader valve 50 is opened.
Then, the hydraulic oil in the tow vehicle-side hydraulic circuit 47 is circulated between the hydraulic pump / motor 35 and the unloader valve 50, so that the tractor 20 can be run without imposing a burden on the hydraulic pump / motor 35. You can Further, when the joint portions 60a and 60b are separated, the hydraulic oil in the hydraulic circuit 63 on the trailing vehicle side cannot wander, so that the trailer 21 is applied with the parking brake. Here, in order to move the separated trailer 21, the unloader valve 64 is opened. Then, the hydraulic fluid in the hydraulic circuit 63 on the side of the trailing vehicle is circulated between the hydraulic pump / motor 36 and the unloader valve 64, so that the trailer 21 should be moved without imposing a burden on the hydraulic pump / motor 36. Is possible.

As described above, according to this embodiment, the hydraulic pump / motor 35 connected to the rear wheel 26 of the tractor 20 and the hydraulic pump / motor 36 connected to the rear wheel 32 of the trailer 21 are looped. By connecting the hydraulic circuit in series, the rear wheel 26 of the tractor 20 and the rear wheel 32 of the trailer 21 can be interlocked without using a complicated interlocking drive mechanism.

Further, since the hydraulic pump / motors 35, 36 are not directly connected to the engine 37, there is little risk of damage to hydraulic equipment such as the hydraulic pumps / motors 35, 36 at the time of overrun. .

Further, since the hydraulic pump / motors 35 and 36 are stopped when the vehicle is stopped, the engine 37 is not burdened.

The hydraulic pump / motor 35, 36
Are tuned and controlled according to the traveling states of the tractor 20 and the trailer 21.

Further, since it is not directly connected to the engine 37, hydraulic components can be made compact.

The hydraulic pump / motors 35 and 36 provided on the tractor 20 side and the trailer 21 side, respectively, when traveling on a flat surface.
The four-wheel full-time running state can be achieved by.

During turning, the synchronized operation of the rear wheels 26 of the tractor 20 and the rear wheels 32 of the trailer 21 is maintained, and the turning traveling of the towing vehicle is stabilized.

During deceleration by the engine brake, retarder brake, auxiliary brake, etc., the rear wheel 26 of the tractor 20 and the rear wheel 32 of the trailer 21 operate simultaneously, so that the towing vehicle can perform stable deceleration.

When traveling downhill, the rear wheels 26 of the tractor 20
And the rear wheel 32 of the trailer 21 are simultaneously decelerated, and the rear impact load generated in the kingpin coupler device 22 provided on the tractor 20 side is alleviated, and the jack knife phenomenon can be prevented.

At the time of starting uphill, since the entire load moves rearward, the load is not applied to the axle 28 on the tractor 20 side, and there is a risk that the rear wheels 26 will slip and it will become impossible to start. The tuning / control function of the dual motors 35 and 36 works, and the hydraulic pump / motor 36 on the trailer 21 side exerts its driving force.
The slip of 6 can be eliminated to facilitate starting.

When a slip phenomenon occurs during traveling on a bad road or a snowy road, the rotation of the slipped axles 28, 34 can be used to drive the other axles 34, 28 to recover the driving force.

Furthermore, the coupling ends 56a, 5 on the tractor 20 side
The hydraulic connection mechanism 58 including the joint 6a and the joint portions 60a and 60b on the trailer 21 side can be easily connected and disconnected by a hydraulic coupler or the like.

Since the hydraulic circuit 47 for the towing vehicle and the hydraulic circuit 63 for the associated vehicle are provided with hydraulic free means such as unloader valves 50, 64, the tractor 20 can be operated independently or the tractor 20 and the trailer 21 can be combined with other vehicles. Can be operated.

[0060]

As described above, according to the first aspect of the invention, the hydraulic actuator connected to the rear wheel portion of the towing vehicle and the hydraulic actuator connected to the rear wheel portion of the trailing vehicle form a loop hydraulic pressure. By connecting in series to the circuit, the rear wheels of the towing vehicle and the rear wheels of the trailing vehicle can be interlocked without using a complicated interlocking drive mechanism. Moreover, since the hydraulic actuator is not connected to the engine in a direct-acting manner, there is less risk of damage to hydraulic equipment such as the hydraulic actuator during overruns. Further, since the hydraulic actuator is in a stopped state when traveling is stopped, the engine is not burdened. The hydraulic actuator is tuned and controlled according to the traveling states of the towing vehicle and the trailing vehicle. Further, since the engine is not directly connected to the engine, hydraulic components can be made compact. When traveling on a flat ground, the four-wheel full-time traveling state can be achieved by the hydraulic actuators provided on the towing vehicle side and the trailing vehicle side, respectively.

According to the second aspect of the present invention, the loop-shaped hydraulic circuit is connected to the return passage for releasing the excess hydraulic oil and the replenishment passage for supplying the shortage of hydraulic oil. Thus, the synchronized operation of the rear wheels of the towing vehicle and the trailing vehicle of the trailing vehicle is maintained, and the turning traveling of the towing vehicle is stabilized.

According to the third aspect of the present invention, the loop-shaped hydraulic circuit is connected to the flow rate regulating means for regulating the flow rate of the hydraulic oil, so that the engine brake, the retarder brake, the auxiliary brake, or the like can be used during deceleration. Since the rear wheels of the towing vehicle and the rear wheels of the trailing vehicle operate simultaneously, the towing vehicle can perform stable deceleration. In addition, when traveling downhill, the rear wheels of the towing vehicle and the trailing wheels of the trailing vehicle are simultaneously in the same deceleration state, and the rear-end collision load generated in the vehicle body coupling device provided on the towing vehicle side is mitigated to prevent the jack knife phenomenon. Can be prevented.

According to the fourth aspect of the present invention, when starting uphill, the entire load moves rearward, so that no load is applied to the axle on the side of the towing vehicle, and the rear wheels slip and become unable to start. However, by operating the actuator rotation restraint means, the tuning / control function of the hydraulic actuator works, the hydraulic actuator on the trailing vehicle side exerts the driving force, and the rear wheel slip caused by the jumping phenomenon is eliminated and the vehicle starts. Can be facilitated. In addition, bad road
When a slip phenomenon occurs during traveling on a snowy road, the rotation of the axles 28, 34 on the slipped side is utilized by activating the actuator rotation restraining means so that the other axle 3
4, 28 can be driven to recover the driving force.

According to the fifth aspect of the invention, since the hydraulic connection mechanism capable of separately connecting the loop hydraulic circuit to the hydraulic circuit on the traction vehicle side and the hydraulic circuit on the trailing vehicle side is provided, the towing vehicle and the trailing vehicle are connected. Can be easily connected and disconnected.

According to the sixth aspect of the present invention, since the hydraulic free means is connected to the loop hydraulic circuit in parallel with the respective hydraulic actuators, the towing vehicle can be operated independently or the towing vehicle and the trailing vehicle can be connected to other vehicles. Can be operated in combination,
That is, it can exert a practically useful effect.

[Brief description of drawings]

FIG. 1 is a schematic side view of an embodiment of the present invention.

FIG. 2 is a schematic plan view of FIG.

FIG. 3 is a plan view, (b) is a side view, and (c) is a rear view of the tractor-side hydraulic pump / motor of FIG.

FIG. 4 is a plan view, (b) is a side view, and (c) is a front view of the trailer hydraulic pump / motor of FIG.

FIG. 5 is a hydraulic system diagram of an embodiment of the present invention.

6A is a side view of a vehicle, FIG. 6B is a plan view of the vehicle, and FIG. 6C is a hydraulic system diagram.

[Fig. 7] Fig. 7 is a side view of the vehicle related to the operation at the time of reverse,
(B) is a vehicle plan view and (c) is a hydraulic system diagram.

FIG. 8 is a plan view of the vehicle related to the operation during turning,
(B) is a hydraulic system diagram.

9A is a side view of the vehicle and FIG. 9B is a hydraulic system diagram related to the operation during downhill traveling.

FIG. 10 is a side view of the vehicle and FIG. 10B is a hydraulic system diagram related to the operation at the time of starting uphill.

[Fig. 11] Operation on slippery road / snow road,
(A) is a side view of the vehicle, (b) is a plan view of the vehicle, and (c) is a hydraulic system diagram.

FIG. 12A is a side view of the vehicle and FIG. 12B is a hydraulic system diagram related to the operation at the time of separation.

13A is a side view of the conventional example, and FIG. 13B is a plan view of the conventional example.

14A is a side view of another conventional example, and FIG. 14B is a plan view of another conventional example.

[Explanation of symbols]

20 Tractor 21 Trailer (accompanying vehicle) 22 King pin coupler device (body connecting device) 26 rear wheel 32 rear wheel 35 Hydraulic pump and motor (hydraulic actuator) 36 Hydraulic pump and motor (hydraulic actuator) 37 engine 47 Tow vehicle hydraulic circuit (loop-shaped hydraulic circuit) 47a Circulation flow path (loop hydraulic circuit) 47b Supply channel 50 Unloader valve (hydraulic free means) 52 Stop valve (actuator rotation restraint means) 55 Return flow path 57 Retarder valve (flow control means) 58 Hydraulic connection mechanism 63 Hydraulic circuit on the vehicle side (loop-shaped hydraulic circuit) 64 Unloader valve (hydraulic free means) 66 Stop valve (actuator rotation restraint means)

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) B62D 53/00 B60K 17/10 B60K 17/356 B62D 53/06

Claims (6)

(57) [Claims] 1. A towing vehicle in which a rear wheel is driven by an engine and is self-propelled, and a trailing vehicle is connected to the vehicle by a vehicle body connecting device so that a hydraulic actuator is provided at a rear wheel portion of the towing vehicle. A vehicle for towing, characterized in that a hydraulic actuator is attached to the rear wheel portion of the trailing vehicle, and both hydraulic actuators are connected in series to a loop hydraulic circuit in addition to being attached. 2. The loop-shaped hydraulic circuit is connected to a return flow path for releasing excess hydraulic oil and a replenishment flow path for replenishing insufficient hydraulic oil. Vehicle for towing. 3. The towing vehicle according to claim 1, wherein a flow rate regulating means for regulating the flow rate of the hydraulic oil is connected to the loop-shaped hydraulic circuit. 4. The traction according to any one of claims 1 to 3, wherein the loop-shaped hydraulic circuit is connected with actuator rotation restraining means for restraining rotation of the hydraulic actuator in parallel with each hydraulic actuator. For vehicles. 5. A hydraulic connection mechanism capable of separately connecting the loop-shaped hydraulic circuit to a tow vehicle-side hydraulic circuit and a trailer-vehicle-side hydraulic circuit, according to any one of claims 1 to 4. Vehicle for towing described. 6. The towing vehicle according to claim 1, wherein a hydraulic free means is connected in parallel with each hydraulic actuator to the loop hydraulic circuit.