JP2002349263A - Drive control device of cooling fan - Google Patents

Abstract

PROBLEM TO BE SOLVED: To install an apparatus in a narrow installing space in a car body without taking the space area when switching the rotational direction of a cooling fan by a directional control valve, and to minimize a device cost by reducing the number of part items such as a pipe and the like by simplifying a structure. SOLUTION: An engine 5, a radiator 23, and the cooling fan 36 are arranged in order on one side in a driver's cabin 21 of a vehicle 20. The directional control valve 12 for switching the rotational direction of the cooling fan 36 is arranged in the close vicinity of the cooling fan 36. The directional control valve 12 is switched to a normal rotation position, and when the cooling fan 36 rotates in the normal rotation direction, the radiator 23 is cooled. The directional control valve 12 is switched to a reverse rotation position, and when the cooling fan 36 rotates in the reverse rotation direction, refuses clogged in the radiator 23 can be blown away.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling fan mounted on a vehicle, and more particularly to a layout relationship with other devices when switching control of the rotation direction of the cooling fan.

[0002]

2. Description of the Related Art Heat generated by an engine of a vehicle such as a construction machine is radiated by a radiator. The radiator is cooled by being blown by a hydraulically driven fan.
The hydraulic drive fan is driven to rotate by a hydraulic motor. The fan used for cooling the radiator only needs to be able to rotate in one direction.

[0003] The direction of rotation differs depending on the type of fan. Therefore, conventionally, a switching valve that switches the rotation direction of the hydraulic motor and switches the rotation direction of the fan according to the type of the fan is provided.

Therefore, if the switching valve can be used to rotate the fan in the reverse direction, dust clogged in the radiator can be blown off to prevent clogging of the radiator.

[0005] Other techniques for preventing clogging of the radiator include the following.

[0006] 1) The engine is stopped, and trash clogged in the radiator is cleaned by the cleaning device.

[0007] 2) A mechanism for changing the mounting angle of the fan is provided. By changing the mounting angle of the fan, the air blowing direction is reversed, and the dust clogged in the radiator is blown off. -312
588, etc.).

However, when the technique 1) is adopted, the engine must be stopped and the cleaning device must be handled, so that there is a problem that a great deal of labor and time is required for the operator.

When the technique 2) is adopted, a complicated mechanism must be mounted on the fan, so that the cost increases and the reliability is lowered due to insufficient strength.

For this reason, a technique using a switching valve for switching the rotation direction of the hydraulic motor has been adopted.

[0011]

Vehicles such as construction machines have been required to be compact in recent years, and accordingly, the installation space for hydraulic equipment has been greatly limited.
Therefore, there is a demand for arranging hydraulic equipment in a limited narrow installation space in a vehicle body without taking up space.
Also, when providing the switching valve, the structure should be simplified,
It is required to reduce the number of parts such as piping and the cost of the apparatus.

Therefore, according to the present invention, when the rotation direction of the cooling fan is switched by the switching valve, the equipment can be installed in a narrow installation space in the vehicle body without taking up space, the structure is simplified, and piping and the like are reduced. It is an object of the present invention to reduce the number of parts and to keep the apparatus cost low.

[0013]

Means for Solving the Problems, Function and Effect The first invention is a vehicle (20) having a cab (21), an engine (5), a radiator (23), and a cooling fan (3).
6), and a drive control device for the cooling fan that cools the radiator (23) by controlling the rotation of the cooling fan (36). On one side, an engine (5), a radiator (23), and a cooling fan (36) are sequentially arranged,
A switching valve (12, 120) for switching the rotation direction of the cooling fan (36) is provided, and the switching valve (12, 12) is provided.
0) is disposed close to the cooling fan (36), and the rotation direction of the cooling fan (36) is switched by switching control of the switching valves (12, 120).

The first invention will be described with reference to FIGS.

As shown in FIG. 1, an engine 5, a radiator 23, a cooling fan 3
6 are sequentially arranged.

Then, as shown in FIG.
The switching valve 12 for switching the rotation direction of the cooling fan 6 is disposed close to the cooling fan 36.

Then, as shown in FIG.
Is switched to the forward rotation position, and when the cooling fan 36 rotates in the forward rotation direction, the radiator 23 is cooled. When the switching valve 12 is switched to the reverse rotation position as shown in FIG. 1B and the cooling fan 36 rotates in the reverse rotation direction, dust clogged in the radiator 23 can be blown off. When the cooling fan 36 rotates in the reverse direction, warm air in the engine room 22
Since the air is blown to the side, the inside of the cab 21 can be heated without providing a heater or the like.

According to the first invention, since the switching valve 12 is arranged close to the cooling fan 36, the cooling fan 36 and the switching valve 12 are housed as shown in FIG. The total length in the vehicle longitudinal direction X including the motor body 11 can be reduced, and the device can be installed in a small installation space in the vehicle 20 without taking up space.

Further, since the switching valve 12 is disposed close to the cooling fan 36, the structure is simplified, and
The number of parts such as joints can be reduced, and the apparatus cost can be reduced.

According to a second aspect of the present invention, a cab (21), an engine (5), and a radiator (23) are provided in a vehicle (20).
And a cooling fan (36) are arranged, and the hydraulic motor (1) drives and controls the rotation of the cooling fan (36) to cool the radiator (23). In the control device, an engine (5), a radiator (23), and a cooling fan (36) are sequentially arranged on one side with respect to an operator's cab (21), and a switching valve for switching the rotation direction of the hydraulic motor (1). (1
2, 120), the switching valve (12, 120) is built into the body (11) of the hydraulic motor (1), and the switching valve (12, 120) is switched to control the cooling fan (12, 120). 36) The rotation direction is switched.

The second invention will be described with reference to FIGS.

As shown in FIG. 1, an engine 5, a radiator 23, a cooling fan 3
6 are sequentially arranged.

Then, as shown in FIG.
A switching valve 12 for switching the rotation direction of the cooling fan 6 is built in the motor body 11 of the hydraulic motor 1 that rotationally drives the cooling fan 36.

Then, as shown in FIG.
Is switched to the forward rotation position, and when the cooling fan 36 rotates in the forward rotation direction, the radiator 23 is cooled. When the switching valve 12 is switched to the reverse rotation position as shown in FIG. 1B and the cooling fan 36 rotates in the reverse rotation direction, dust clogged in the radiator 23 can be blown off. When the cooling fan 36 rotates in the reverse direction, warm air in the engine room 22
Since the air is blown to the side, the inside of the cab 21 can be heated without providing a heater or the like. Further, the warm-up of the engine 5 can be hastened.

According to the second aspect of the present invention, the switching valve 12 is incorporated in the motor body 11 of the hydraulic motor 1, so that the cooling fan 36 and the switching valve 1 are provided as shown in FIG.
The length in the vehicle longitudinal direction X, which is the sum of the length of the motor body 11 and the motor body 11 having the built-in 2, can be shortened, and the equipment can be installed in a small installation space in the vehicle 20 without taking up space.

Since the switching valve 12 is built in the motor body 11 of the hydraulic motor 1, the switching valve 12 and the hydraulic motor 1
The structure is simpler than in the case where they are separate bodies, and the number of parts such as pipelines and joints can be reduced, and the apparatus cost can be reduced.

A third invention is characterized in that, in the first invention or the second invention, the engine (5) is arranged so that its longitudinal direction coincides with the vehicle width direction.

According to the third aspect of the present invention, as shown in FIG. 2, the engine 5 is arranged so that its longitudinal direction coincides with the vehicle width direction Y, so that the length of the vehicle longitudinal direction X can be further reduced. The device can be installed in the small installation space in the device 20 without taking up space.

According to a fourth aspect of the present invention, in the first or second aspect, a rotation center portion (32) of the cooling fan (36) is provided.
Is formed in a concave portion, and the switching valve (12, 1, 1) is formed in the concave portion.
A driving unit (11) including the driving unit (20) is housed.

According to the fourth aspect of the present invention, as shown in FIG. 4, the boss portion 32 as the center of rotation of the cooling fan 36 is formed in a concave portion, and the motor body 11 including the switching valve 12 is formed in the concave portion. As a result, the total length of the cooling fan 36 and the motor body 11 in the longitudinal direction X of the vehicle is shorter than that of the conventional one by ΔX, so that the equipment can be installed in a small installation space in the vehicle 20 without taking up space. Can be installed.

[0031]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a cooling fan drive control device according to the present invention will be described below. In the present embodiment, it is assumed that a cooling fan is mounted on a construction machine such as a bulldozer, a wheel loader, a dump truck, and a hydraulic shovel. However, the present invention is not limited to a construction machine, and can be applied to a case where a cooling fan is mounted on another work machine or a vehicle such as a general automobile. In this embodiment, a hydraulically driven fan driven by hydraulic pressure is assumed as the cooling fan. However, the present invention is not limited to a hydraulic drive fan, but can be applied to an electric fan.

FIG. 1 shows an arrangement relationship of each device mounted on the vehicle 20 of the embodiment.

In FIG. 1, the longitudinal direction of the vehicle 20 is represented by X, and the vehicle width direction is represented by Y. The vehicle 20 is provided with a crawler belt 24, and when the crawler belt 24 rotates, the longitudinal direction X
To travel.

That is, as shown in FIG. 1, the engine 5, the radiator 23, and the cooling fan 36 are sequentially arranged on one side of the cab 21 of the vehicle 20.

FIG. 4 shows an arrangement relationship between the cooling fan 36 and the motor body 11 as a drive unit for driving the cooling fan 36.

As shown in FIG. 4, the cooling fan 36 is roughly composed of a boss 32 as a rotation center and a blade 3.
0. The boss portion 32 and the blade portion 30 are connected by being fastened with a bolt 31.

The boss 30 is formed in a recess. In the boss portion 30 formed in this concave portion, the motor body 11
Is housed. The motor body 11 houses the hydraulic motor 1 and a switching valve 12 described later. The switching valve 12 is a control valve that switches the rotation direction of the hydraulic motor 1 between a forward rotation direction and a reverse rotation direction.

The rotating shaft of the hydraulic motor 1 is
6 is fixed to the boss 32.

As a result, the cooling fan 36 is rotated by driving the hydraulic motor 1 to rotate. Switching valve 12
The rotation direction of the hydraulic motor 1 is thereby switched, whereby the rotation direction of the cooling fan 36 is switched.

The motor body 11 is connected to a pipe 33 for supplying pressure oil to the switching valve 12 and discharging pressure oil from the switching valve 12.

As described above, the switching valve 12 is provided with the cooling fan 3.
6 is provided in the vicinity. Moreover, the motor body 11
The switching valve 12 is built therein.

Therefore, the drive unit for driving the cooling fan 36 can be made compact and can have a simple structure. Further, a motor body 11 having a built-in switching valve 12
Is accommodated in the boss portion 32 of the cooling fan 36, so that the total length of the cooling fan 36 and the motor body 11 can be reduced.

A comparison with the conventional device configuration will be made with reference to FIG.
According to the conventional configuration, the boss 32 of the cooling fan 36 is not formed in the recess. Therefore, the cooling fan 36
And the motor body 11 ', the total length in the vehicle longitudinal direction X is large. In addition, since the motor body 11 'and the switching valve 12 are separate bodies, an extra space corresponding to the switching valve 12 is taken.

On the other hand, according to the present embodiment, since the motor body 11 is housed in the boss portion 32 of the cooling fan 36, the cooling fan 36 and the motor body 11
And the total length in the vehicle longitudinal direction X is shorter by ΔX than the conventional one. Further, since the switching valve 12 is built in the motor body 11, no further space is required.

As described above, according to the present embodiment, the cooling fan 36, the hydraulic motor 1, and the switching valve 12 are connected to the vehicle 20.
It can be installed in a small installation space without taking up space.

Since the switching valve 12 is incorporated in the motor body 11, the structure is simpler than when the switching valve 12 and the hydraulic motor 1 are separate parts, and the number of parts such as pipes and joints is reduced. Therefore, the cost can be reduced and the apparatus cost can be reduced.

The rotation switching control of the cooling fan 36 can be performed by either open loop control or closed control (feedback control).

When switching control is performed by open loop control, a time measuring means such as a timer is provided. The contents of the control for switching the rotation direction of the cooling fan 36 will be described with reference to FIG.

FIG. 10 shows a time chart of the embodiment. The horizontal axis in FIG. 10 indicates time, and the vertical axis indicates “forward rotation”,
"Rotation stop" and "reverse rotation" are shown.

That is, T1 (for example, 1
Until 5 minutes) is counted, the switching valve 12 is in the forward rotation position, and the cooling fan 36 rotates forward for the time T1. When T1 is counted by the timer, the rotational drive of the hydraulic motor 1 is stopped as described later. The rotation of the hydraulic motor 1 is stopped until T2 (for example, 10 seconds to several tens of seconds) is measured by the timer, and the rotation of the cooling fan 36 is stopped for the time T2. When T2 is counted by the timer, the switching valve 12 is switched to the reverse rotation position. T3 depending on the timer (eg 2-3 minutes)
Until is measured, the switching valve 12 is in the reverse rotation position, and the cooling fan 36 rotates in the reverse direction for the time T3.

The above processing is repeatedly executed.

Here, when the cooling fan 36 is switched from forward rotation to reverse rotation or from reverse rotation to forward rotation,
The reason why the rotation of the hydraulic motor 1 is stopped for a predetermined time T2 is to prevent cavitation and noise.

When switching control is performed by feedback control, an air flow detecting sensor for detecting the amount of air passing through the radiator 23 is provided. Therefore, a threshold value is set for the detection value of the air volume detection sensor. This threshold value is set to a value that can determine whether or not clogging of the radiator 23 with dust has occurred.

If the air flow detected by the air flow detection sensor is equal to or greater than the threshold value, it is determined that clogging due to dust has not occurred in the radiator 23, and the switching position of the switching valve 12 is set to the forward rotation position. The cooling fan 36 is maintained at the normal rotation.

However, when the air volume detected by the air volume detection sensor becomes smaller than the above threshold value, the radiator 23
It is determined that clogging due to dust has occurred, and after the rotation of the hydraulic motor 1 has been stopped for a predetermined time T2,
The switching position of the switching valve 12 is switched to the reverse rotation position, and the cooling fan 36 rotates in the reverse direction.

Therefore, the air volume detected by the air volume detection sensor is
When the pressure exceeds the threshold value, the rotation of the hydraulic motor 1 is stopped for a predetermined time T2, and then the switching position of the switching valve 12 is switched to the forward rotation position, and the cooling fan 36 is rotated.
Rotates forward.

When the switching control is performed by the feedback control, the cooling fan 36 rotates in the reverse direction for the minimum necessary time, so that the cooling efficiency of the radiator 23 is improved as compared with the open loop control.

FIG. 1 shows the flow of the wind accompanying the rotation of the cooling fan 36.

As shown in FIG. 1A, when the switching valve 12 is switched to the normal rotation position and the cooling fan 36 rotates in the normal rotation direction, the air passing through the radiator 23 as indicated by the arrow is cooled by the cooling fan. The air is sucked into 36 and exhausts the air in front of the vehicle 20. Thereby, the radiator 23 is cooled.

When the switching valve 12 is switched to the reverse rotation position as shown in FIG. 1B and the cooling fan 36 rotates in the reverse rotation direction, the air in front of the vehicle 20 is cooled as shown by the arrow. The air is sucked into the fan 36 and discharged toward the radiator 23. As a result, dust clogged in the radiator 23 can be blown off. At this time, warm air in the engine room 22 is blown toward the cab 21 side. Therefore, warm air in the engine room 22 can be introduced into the operation room 21 by providing ventilation holes in the wall 25 separating the engine room 22 and the operation room 21. For this reason, the cab 2 is provided without providing a heater or the like.
1 can be heated. Further, the warm-up of the engine 5 can be hastened.

In FIG. 1, the engine 5 is arranged so that its longitudinal direction coincides with the vehicle longitudinal direction X. However, as shown in FIG. 2, the engine 5 is arranged so that its longitudinal direction coincides with the vehicle width direction Y. May be arranged. When such an arrangement is adopted, the length of the engine room 22 in the vehicle longitudinal direction X can be further reduced, and various devices can be installed in a small installation space in the vehicle 20 without taking up space. Will be possible.

As shown in FIG. 3, the engine room 22, the radiator room 27, and the wall 26 may be used to partition the engine. The engine 5 is arranged in the engine room 22, and the radiator 23 and the cooling fan 36 are arranged in the radiator room 27.

FIG. 5 shows a hydraulic circuit according to the first embodiment.

As shown in FIG. 5, the apparatus according to the embodiment is roughly divided into a pump body 110 of the hydraulic pump 2, a motor body 11 of the hydraulic motor 1, a cooling fan 36, and a rotation direction of the cooling fan 36. And a controller 37 for switching control of

The hydraulic pump 2 is a variable displacement hydraulic pump. However, implementation using a constant displacement hydraulic pump is also possible.

The hydraulic pump 2 is driven by the engine 5 and discharges pressure oil to a pump discharge oil passage 7. The electromagnetic proportional control valve 38 guides a pilot pressure corresponding to the electric command signal output from the controller 37 to the swash plate drive unit 39. The swash plate drive unit 39 drives the swash plate 2a of the hydraulic pump 2 according to the pilot pressure guided from the electromagnetic proportional control valve 38, and drives the hydraulic pump 2
Change the capacity of

The pump discharge oil passage 7 is connected to the pump port P of the switching valve 12 via the switching valve 40.

The switching valve 40 is a two-position switching valve having a pressure oil supply position 40a and a pressure oil cutoff position 40b. Switching valve 4
0 is built in the pump body 110.

The electromagnetic proportional control valve 41 guides a pilot pressure according to an electric command signal output from the controller 37 to a pilot port 40c of the switching valve 40.

The position of the switching valve 40 changes in accordance with the pilot pressure acting on the pilot port 40c. When the switching valve 40 is switched to the pressure oil supply position 40a, the pressure oil discharged from the hydraulic pump 2 passes through the switching valve 40 and is supplied to the pump port P of the switching valve 12. When the switching valve 40 is switched to the pressure oil shutoff position 40b, the pressure oil discharged from the hydraulic pump 2 is shut off by the switching valve 40 and discharged to the tank 3 without being supplied to the pump port P of the switching valve 12.

The switching valve 12 and the hydraulic oil supply / discharge ports MA and MB of the hydraulic motor 1 are connected by oil passages 74 and 75, respectively.

The switching valve 12 inputs the pressure oil discharged from the pump via the oil passage 7, controls the direction of the pressure oil, and supplies the pressure oil to the port MA or the port MB of the hydraulic motor 1.

The switching valve 12 has a forward rotation position A and a reverse rotation position B
And a two-position switching valve having: The switching valve 12 is built in the motor body 11 as described above.

The electromagnetic proportional control valve 42 is a two-position switching valve having a low pressure position 42a and a high pressure position 42b. The position of the electromagnetic proportional control valve 42 is switched according to an electric command signal output from the controller 37. When the electromagnetic proportional control valve 42 is switched to the high-pressure position 42b, the high-pressure pump discharge pressure in the pump discharge oil passage 7 is used as a pilot pressure to control the pilot port 12c of the switching valve 12 via the oil passage 44.
Lead to. When the electromagnetic proportional control valve 42 is switched to the low pressure position 42a, the pilot port 12c of the switching valve 12
Communicates with the tank 3 and the pilot port 12 of the switching valve 12
A low pilot pressure acts on c.

The switching valve 12 is located at the forward rotation position A when a low pilot pressure acts on the pilot port 12c, and is located at the reverse rotation position B when a high pilot pressure acts on the pilot port 12c.

When the switching valve 12 is located at the normal rotation position A,
Pressure oil is supplied to the port MA of the hydraulic motor 1 and the hydraulic motor 1 rotates in the forward direction. When the switching valve 12 is located at the reverse rotation position B, pressure oil is supplied to the port MB of the hydraulic motor 1 and the hydraulic motor 1 rotates in the reverse direction.

The suction valve 13 and the safety valve 4 are arranged upstream of the switching valve 12.

The suction valve 13 is built in the motor body 11. The safety valve 4 is built in the pump body 110.

The tank port T of the switching valve 12 communicates with the oil passage 6. The oil passage 6 and the pump discharge oil passage 7 are connected by an oil passage 8.

The oil passage 8 is provided with a suction valve 13.
The suction valve 13 guides the pressure oil discharged from the tank port T of the switching valve 12 only from the oil passage 6 to the pump discharge oil passage 7.

The pump discharge oil passage 7 branches into an oil passage 9, on which a safety valve 4 is provided. The safety valve 4 guides the pressure oil to the tank 3 when the oil pressure of the pump discharge oil passage 7 becomes equal to or higher than a set pressure.

Next, the operation performed in the first embodiment shown in FIG. 5 will be described.

When switching the cooling fan 36 in the forward rotation direction, the controller 37 outputs an electric command signal for positioning the switching valve 40 to the pressure oil supply position 40a to the electromagnetic proportional control valve 41, and the electromagnetic proportional control valve. An electric command signal for positioning the switching valve 12 at the low pressure position 42 a and the switching valve 12 at the normal rotation position A is output to the electromagnetic proportional control valve 42.

When the switching valve 40 is located at the pressure oil supply position 40a and the switching valve 12 is located at the normal rotation position A, the pressure oil discharged from the hydraulic pump 2 is supplied to the pump discharge oil passage 7, the switching valve 4
0, which passes through the switching valve 12 and is supplied to the port MA of the hydraulic motor 1 via the oil passage 74. Thereby, the hydraulic motor 1
Rotates forward, and the cooling fan 36 rotates in the forward direction.

When the rotation of the hydraulic motor 1 is stopped, the controller 37 issues an electric command signal for positioning the switching valve 40 to the pressure oil cutoff position 40b.
Is output to

When the switching valve 40 is located at the pressure oil shut-off position 40b, the pressure oil discharged from the hydraulic pump 2 is shut off by the switching valve 40 and the pressure oil is not supplied to the pump port P of the switching valve 12. Therefore, no pressure oil is supplied to any of the ports MA and MB of the hydraulic motor 1.

The hydraulic motor 1 keeps rotating due to the driving force received from the load and the inertia of the hydraulic motor 1 itself. At this time, the hydraulic motor 1 performs a pump function of discharging pressure oil from the port MB. Therefore, the pressure oil in the oil passage 6 communicating with the port MB has a higher pressure than that in the pump discharge oil passage 7. At this time, the high pressure oil in the oil passage 6 is guided to the pump discharge oil passage 7 via the suction valve 13 on the oil passage 8. Therefore, high pressure oil is sucked into the port MA of the hydraulic motor 1.

When the cooling fan 36 is switched in the reverse rotation direction, the controller 37 outputs an electric command signal for positioning the switching valve 40 to the pressure oil supply position 40a to the electromagnetic proportional control valve 41 and the electromagnetic proportional control valve. An electric command signal for positioning the switch 42 at the high pressure position 42b and the switching valve 12 at the reverse rotation position B is output to the electromagnetic proportional control valve 42.

When the switching valve 40 is located at the pressure oil supply position 40a and the switching valve 12 is located at the reverse rotation position B, the pressure oil discharged from the hydraulic pump 2 is supplied to the pump discharge oil passage 7 and the switching valve 4
0, it passes through the switching valve 12 and is supplied to the port MB of the hydraulic motor 1 via the oil passage 75. Thereby, the hydraulic motor 1
Rotate in the reverse direction, and the cooling fan 36 rotates in the reverse direction.

Next, a structural example of the hydraulic motor 1 according to the first embodiment will be described with reference to FIGS.

FIG. 6 is a sectional view of the motor body 11 of the hydraulic motor 1.

FIG. 7 is a sectional view of the motor body 11 shown in FIG.
It is A sectional drawing.

As shown in FIG. 7, a spool 10 of a switching valve 12 is slidably accommodated in a motor body 11. Pilot port 12c on the right side of spool 10 in the figure
, A pilot pressure acts via an electromagnetic proportional control valve 42.

The operation of FIG. 7 will be described.

The spool 1 is controlled via the electromagnetic proportional control valve 42.
When a low pilot pressure is acting on the zero pilot port 12c, the spool 10 is located on the right side as shown. In this position, the pump port P communicates with the port MA, and the port MB communicates with the tank port T. Therefore, the pressure oil discharged from the hydraulic pump 2 is supplied to the port MA of the hydraulic motor 1 through the pump discharge oil passage 7 and the opening of the spool 10. This causes the hydraulic motor 1 to rotate forward.

The spool 1 is controlled via the electromagnetic proportional control valve 42.
When a high pilot pressure in the oil passage 7 is acting on the zero pilot port 12c, the spool 10 moves to the left from the illustrated position. When the spool 10 is located on the left side in the figure, the pump port P communicates with the port MB, and the port MA communicates with the tank port T. Accordingly, the pressure oil discharged from the hydraulic pump 2 is supplied to the port MB of the hydraulic motor 1 via the pump discharge oil passage 7 and the opening of the spool 10. This causes the hydraulic motor 1 to rotate in the reverse direction.

As described above, according to the first embodiment, the switching valve 40 is controlled to switch between the pressure oil supply position 40a and the pressure oil cutoff position 40b, and the switching valve 12 is switched to the normal rotation position A and the reverse rotation position B. By performing the switching control, the rotation drive of the hydraulic motor 1 can be stopped and the rotation of the cooling fan 36 can be stopped without stopping the engine 5 at the time of switching the normal / reverse rotation of the cooling fan 36. Therefore, when switching between the forward and reverse rotations of the cooling fan 36, the troublesome operation of temporarily stopping the engine 5 and restarting the engine 5 is not required, and the working efficiency can be improved. In the above-described first embodiment, the switching valve 40 is provided separately from the switching valve 12 in the motor body 11, but a second embodiment in which the switching valve 40 is unnecessary will be described.

FIG. 8 shows a hydraulic circuit according to the second embodiment. Hereinafter, in FIG. 8, components using the same reference numerals as those in the first embodiment of FIG. 5 are the same components, and description thereof will be omitted as appropriate.

As shown in FIG. 8, the pump discharge oil passage 7 is connected to the pump port P of the switching valve 120.

The switching valve 120 corresponds to the switching valve 12 described above, and similarly to the switching valve 12, receives the pump discharge pressure oil via the oil passage 7 and controls the direction of the pressure oil to control the hydraulic motor 1 Pressure oil is supplied to the port MA or the port MB.

The switching valve 120 is a three-position switching valve having a stop position C in addition to a forward rotation position A and a reverse rotation position B.

The electromagnetic proportional control valve 42 is a two-position switching valve having a low pressure position 42a and a high pressure position 42b. The position of the electromagnetic proportional control valve 42 is switched according to an electric command signal output from the controller 37. When the electromagnetic proportional control valve 42 is switched to the high pressure position 42b, the pilot port 12 of the switching valve 120 is switched via the oil passage 44 using the high pressure pump discharge pressure in the pump discharge oil passage 7 as the pilot pressure.
0c. Also, the electromagnetic proportional control valve 42 is in the low pressure position 42a.
, The pilot port 120c of the switching valve 120 communicates with the tank 3 and a low pilot pressure acts on the pilot port 120c of the switching valve 120.

The pilot port 120c of the switching valve 120
A rod 45 is provided on the side opposite to. The rod 45 operates according to the pilot pressure acting on the pilot port 45c, and applies a force opposing the pilot pressure acting on the pilot port 120c to the switching valve 120.

The electromagnetic proportional control valve 43 is a two-position switching valve having a low pressure position 43a and a high pressure position 43b. The valve position of the electromagnetic proportional control valve 43 is switched according to an electric command signal output from the controller 37. When the electromagnetic proportional control valve 43 is switched to the high pressure position 43b, the high pressure pump discharge pressure in the pump discharge oil passage 7 is guided to the pilot port 45c of the rod 45 as pilot pressure. When the electromagnetic proportional control valve 43 is switched to the low pressure position 43a,
The pilot port 45c of the rod 45 communicates with the tank 3 and a low pilot pressure acts on the pilot port 45c of the rod 45.

The switching valve 120 is connected to the pilot port 120
When a low pilot pressure acts on c and a high pilot pressure acts on the pilot port 45c of the rod 45, the rod 45 is positioned at the normal rotation position A. The switching valve 120 is located at the reverse rotation position B when a high pilot pressure acts on the pilot port 120c and a low pilot pressure acts on the pilot port 45c of the rod 45. The switching valve 120 is positioned at the stop position C when a high pilot pressure acts on the pilot port 120c and a high pilot pressure acts on the pilot port 45c of the rod 45.

When the switching valve 120 is located at the forward rotation position A, pressure oil is supplied to the port MA of the hydraulic motor 1 and the hydraulic motor 1 rotates in the forward direction. When the switching valve 120 is located at the reverse rotation position B, pressure oil is supplied to the port MB of the hydraulic motor 1 and the hydraulic motor 1 rotates in the reverse direction.

When the switching valve 120 is located at the stop position C, pressure oil is supplied to both the ports MA and MB of the hydraulic motor 1. At this time, both ports MA and MB communicate with the tank 3.

Next, the operation performed in the second embodiment shown in FIG. 8 will be described.

When the cooling fan 36 is switched in the forward rotation direction, the controller 37 sends the electromagnetic proportional control valve 4
2 is positioned at the low pressure position 42a, the electromagnetic proportional control valve 43 is positioned at the high pressure position 43b, and the electric command signal for positioning the switching valve 120 at the normal rotation position A is transmitted to the electromagnetic proportional control valve 42,
43.

When the switching valve 120 is located at the normal rotation position A, the pressure oil discharged from the hydraulic pump 2 passes through the pump discharge oil passage 7 and the switching valve 120, and passes through the oil passage 74 to the port MA of the hydraulic motor 1. Supplied to As a result, the hydraulic motor 1 rotates forward, and the cooling fan 36 rotates in the forward direction.

When the rotational drive of the hydraulic motor 1 is stopped, the controller 37 places the electromagnetic proportional control valve 42 at the high pressure position 42b, positions the electromagnetic proportional control valve 43 at the high pressure position 43b, and stops the switching valve 120. An electric command signal for positioning the position C is output to the electromagnetic proportional control valves 42 and 43.

When the switching valve 120 is located at the stop position C,
The pressure oil discharged from the hydraulic pump 2 is supplied to both ports MA and MB of the hydraulic motor 1. At this time, the ports MA and MB of the hydraulic motor 1 communicate with the tank 3. As a result, the rotation drive of the hydraulic motor 1 is stopped, and the rotation of the cooling fan 3 is stopped.

When the cooling fan 36 is switched in the reverse rotation direction, the controller 37 sends the electromagnetic proportional control valve 4
2 at the high pressure position 42b, the electromagnetic proportional control valve 43 at the low pressure position 43a, and the switching valve 120 at the reverse rotation position B.
43.

When the switching valve 120 is located at the reverse rotation position B, the pressure oil discharged from the hydraulic pump 2 passes through the pump discharge oil passage 7 and the switching valve 120 and passes through the oil passage 75 to the port MB of the hydraulic motor 1. Supplied to As a result, the hydraulic motor 1 rotates in the reverse direction, and the cooling fan 36 rotates in the reverse direction.

Next, an example of the structure of the hydraulic motor 1 according to the second embodiment will be described with reference to FIG.

FIG. 9 is a sectional view of the motor body 11 shown in FIG.
It is A sectional drawing.

As shown in FIG. 9, a spool 100 of the switching valve 120 is slidably housed in the motor body 11. Pilot port 1 on the right side of spool 100 in the figure
Pilot pressure acts on 20 c via an electromagnetic proportional control valve 42. Pilot pressure acts on the pilot port 45c of the rod 45 on the left side of the spool 100 in the drawing via the electromagnetic proportional control valve 43.

The operation of FIG. 9 will be described.

The spool 1 is controlled via the electromagnetic proportional control valve 42.
When a low pilot pressure acts on the pilot port 120c of the oil passage 7 and the high pilot pressure in the oil passage 7 acts on the pilot port 45c of the rod 45 via the electromagnetic proportional control valve 43, as shown in the figure. Spool 1
00 is located on the right side. In this position, the pump port P communicates with the port MA, and the port MB connects with the tank port T.
Communicate with Therefore, the pressure oil discharged from the hydraulic pump 2 is supplied to the port MA of the hydraulic motor 1 through the pump discharge oil passage 7 and the opening of the spool 100. This causes the hydraulic motor 1 to rotate forward.

The spool 1 is controlled via the electromagnetic proportional control valve 42.
When the high pilot pressure in the oil passage 7 acts on the pilot port 120c of the oil passage 7 and the high pilot pressure in the oil passage 7 also acts on the pilot port 45c of the rod 45, the spool 100 is illustrated. From the current position to the left position. Spool 10
0 is positioned at the neutral position on the left side in the figure, the pump port P communicates with both the ports MA and MB, and the port M
Both A and MB communicate with the tank port T. As a result, the rotational drive of the hydraulic motor 1 stops.

The spool 1 is controlled via the electromagnetic proportional control valve 42.
When a high-pressure pilot pressure in the oil passage 7 acts on the pilot port 120c of the oil passage 7 and a low-pressure pilot pressure acts on the pilot port 45c of the rod 45, the spool 100 moves further leftward from the above-described neutral position. Moving. When the spool 100 is located further to the left of the neutral position, the pump port P communicates with the port MB, and the port MA communicates with the tank port T. Therefore, the pressure oil discharged from the hydraulic pump 2 is supplied to the port MB of the hydraulic motor 1 through the pump discharge oil passage 7 and the opening of the spool 100. This causes the hydraulic motor 1 to rotate in the reverse direction.

As described above, according to the second embodiment, the switching valve 120 is set at the forward rotation position A, the stop position C, and the reverse rotation position B.
By performing the switching control, the rotation drive of the hydraulic motor 1 can be stopped and the rotation of the cooling fan 36 can be stopped without stopping the engine 5 at the time of switching the normal / reverse rotation of the cooling fan 36. Therefore, the cooling fan 3
At the time of the forward / reverse rotation switching of 6, the troublesome operation of temporarily stopping the engine 5 and restarting the engine 5 is not required, and the working efficiency can be improved. Moreover, according to the second embodiment, the switching valve 40 of the first embodiment is not required for performing the switching control, and the structure is further simplified.

In the embodiment described above, the spool 1
The description has been made assuming the switching valves 12 and 120 in which the valve positions are switched by the direct movement of 0 and 100. However, you may use what is called a rotary type switching valve in which a valve position is switched by rotation of a spool.

FIG. 11 shows a hydraulic circuit of a third embodiment in which the switching valve 12 in the first embodiment shown in FIG. 5 is replaced with a rotary type switching valve 121.

That is, as shown in FIG. 11, the electromagnetic proportional control valve 42 shown in FIG.
3 are provided. Rotation axis 1 of stepping motor 113
13a is connected to the spool 130 of the switching valve 121.

Rotary shaft 113 of stepping motor 113
a rotates according to an electric command signal output from the controller 37. The spool 130 of the switching valve 121 rotates with the rotation of the rotating shaft 113a. As the spool 130 is positioned at each predetermined rotation angle, the switching valve 1
Reference numeral 21 denotes a forward rotation position A and a reverse rotation position B.

When the switching valve 121 is located at the forward rotation position A, pressure oil is supplied to the port MA of the hydraulic motor 1 and the hydraulic motor 1 rotates in the forward direction. When the switching valve 121 is located at the reverse rotation position B, pressure oil is supplied to the port MB of the hydraulic motor 1 and the hydraulic motor 1 rotates in the reverse direction.

FIG. 12 is a sectional view of the motor body 11 shown in FIG. FIG. 12A shows a state in which the switching valve 121 is located at the forward rotation position A, and FIG.
Numeral 1 indicates a main part in a state where it is located at the reverse rotation position B.

As shown in FIG. 12, a spool 130 of the switching valve 121 is housed in the motor body 11 so as to rotate about an axis automatically. Notch 13 in spool 130
1, 132 are formed.

The operation of FIG. 12 will be described.

When an electric command signal for causing the stepping motor 113 to move to the normal rotation position A is given from the controller 37, the spool 130 is positioned at a rotation angle as shown in FIG. Spool 13
When 0 is at this rotation angle, the pump port P communicates with the port MA via the notch 131, and the port MB communicates with the tank port T via the notch 132. Accordingly, the pressure oil discharged from the hydraulic pump 2 is supplied to the pump discharge oil passage 7, the pump port P of the switching valve 121,
1 to the port MA of the hydraulic motor 1.
This causes the hydraulic motor 1 to rotate forward.

When an electric command signal for causing the stepping motor 113 to move to the reverse rotation position B is given from the controller 37, the spool 130 is further rotated clockwise by 90 ° from the rotation angle of FIG. Fig. 12
It is positioned at the rotation angle as shown in FIG. When the spool 130 is positioned at this rotation angle, the pump port P communicates with the port MB via the notch 131, and the port MA communicates with the tank port T via the notch 132. Therefore, the pressure oil discharged from the hydraulic pump 2 is supplied to the port MB of the hydraulic motor 1 through the pump discharge oil passage 7, the pump port P of the switching valve 121, and the notch 131. This causes the hydraulic motor 1 to rotate in the reverse direction.

The above description has been made on the assumption that the switching valve 12 in the first embodiment shown in FIG. 5 is replaced by a rotary type switching valve 121. However, the switching valve 120 in the second embodiment shown in FIG. Can be replaced with a rotary type switching valve.

In FIGS. 1 to 3, the engine 5 is arranged on one side of the cab 21. In this case, however, the direction in which the driver's seat is arranged in the cab 21 is arbitrary. The driver's seat may be arranged such that the engine is arranged in front of the line of sight of the operator, or the driver's seat may be arranged such that the engine is arranged behind the line of sight of the operator.

[Brief description of the drawings]

FIGS. 1A and 1B are layout diagrams of a cooling fan. FIG.

FIG. 2 is a layout view of a cooling fan.

FIG. 3 is a layout view of a cooling fan.

FIG. 4 is a sectional view of a cooling fan.

FIG. 5 is a hydraulic circuit diagram of the first embodiment.

FIG. 6 is a sectional view of a hydraulic motor.

7 is a sectional view of the hydraulic motor according to the first embodiment, and is a sectional view taken along line AA of FIG.

FIG. 8 is a hydraulic circuit diagram of a second embodiment.

FIG. 9 is a sectional view of a hydraulic motor according to a second embodiment, and is a sectional view taken along line AA of FIG. 6;

FIG. 10 is a diagram showing forward / reverse switching control.

FIG. 11 is a hydraulic circuit diagram of a third embodiment.

FIGS. 12A and 12B are cross-sectional views of a hydraulic motor according to a third embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hydraulic motor 5 Engine 11 Motor body 12, 120, 121 Switching valve 20 Vehicle 21 Operator's cab 23 Radiator 32 Boss part 36 Cooling fan

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) F01P 5/04 F01P 5/04 C F15B 9/14 F15B 9/14 Z F-term (reference) 2D015 CA02 EC01 3D038 AA04 AB04 AC01 3H001 AA07 AB04 AD04 AE11

Claims (4)

[Claims] 1. A cab (21) in a vehicle (20).
, An engine (5), a radiator (23), and a cooling fan (36), and the cooling fan (36)
By controlling the rotation of the radiator (2)
3) In a drive control device for a cooling fan configured to cool the engine, an engine (5), a radiator (23), and a cooling fan (36) are sequentially arranged on one side of the cab (21); A switching valve (12, 120) for switching the rotation direction of the cooling fan (36) is provided, and the switching valve (12, 120) is connected to the cooling fan (3).
6) A drive control device for a cooling fan, wherein the rotation direction of the cooling fan (36) is switched by controlling the switching of the switching valves (12, 120). 2. A driver's cab (21) in a vehicle (20).
, An engine (5), a radiator (23), and a cooling fan (36), and the hydraulic motor (1) drives and controls the rotation of the cooling fan (36) to thereby control the rotation of the radiator (23). In the drive control device for a cooling fan configured to cool the cooling fan, an engine (5), a radiator (23), and a cooling fan (36) are sequentially arranged on one side of the cab (21); A switching valve (12, 120) for switching the rotation direction of the hydraulic motor (1) is provided; the switching valve (12, 120) is built in a body (11) of the hydraulic motor (1); A drive control device for a cooling fan, characterized by switching the rotation direction of the cooling fan (36) by switching control of (120). 3. The drive control device for a cooling fan according to claim 1, wherein the engine (5) is arranged so that a longitudinal direction thereof coincides with a vehicle width direction. 4. A cooling center (32) of the cooling fan (36) is formed in a recess, and a drive unit (11) including the switching valves (12, 120) is housed in the recess. The drive control device for a cooling fan according to claim 1 or 2, wherein