JP2000120437A - Cooling fan driving device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cooling fan driving device capable of moving a cooling fan, and of securing safety with the rotation suspended of the cooling fan when the cooling fan is moved. SOLUTION: In this cooling fan driving device for a construction machine, which is provided with a work machine at the front part of a car body, and an engine and a radiator, which are disposed at the rear part, and with a cooling fan for cooling the radiator, a fan mounting frame body supporting the cooling fan is mounted to the radiator so as to be freely opened/closed, opening/closing detection means 30 and 31 detecting the opening/closing of the fan mounting frame body is provided, and concurrently, a fan rotation control means 20 is provided, which suspends the rotation of the cooling fan when the fan mounting frame body is opened while the cooling fan is being rotated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling fan drive device for a construction machine, in which a fan mounting frame supporting a cooling fan for cooling a radiator can be freely opened and closed, and in particular, safety during opening and closing can be ensured. The present invention relates to a driving device for a cooling fan.

[0002]

2. Description of the Related Art FIG. 6 is a side view of an ordinary wheeled construction machine 1. The wheeled construction machine 1 has a working machine 3 provided in front of a vehicle body 2, and has an engine 4 at a rear portion of the vehicle body 2 and a radiator 5 behind the engine 4. A cooling fan 7 driven by a hydraulic motor 6 is provided further behind the radiator 5, and the cooling fan 7 and the hydraulic motor 6 are directly connected. When the engine 4 starts, a hydraulic pump (not shown) rotates to supply hydraulic oil to a hydraulic motor 6, which drives a cooling fan 7 to rotate the radiator 5.
To cool. That is, while the engine 4 is rotating, the cooling fan 7 always rotates.

[0003]

In recent years, in order to facilitate the cleaning of the surface of the radiator 5 on the side of the cooling fan 7, it has been required to employ a cooling fan driving device in which the cooling fan 7 can be moved. In this cooling fan drive,
As shown in FIG. 6, the hydraulic motor 6 that rotationally drives the cooling fan 7 is attached to the fan mounting frame 10. The rear of the cooling fan 7 is covered by a safety net (not shown) so as to cover the cooling fan 7. One end of the fan mounting frame 10 is rotatably attached via a hinge 11 to a fan shroud 8 attached to a rear portion of the radiator 5. When cleaning the side of the radiator 5 facing the cooling fan 7, the fan mounting frame 10 is rotated about the hinge 11 to rotate the cooling fan 7 as shown by a thin two-dot chain line in the figure. Away from it to allow easy cleaning.

[0004] However, the following problems occur in the cooling fan driving device which is movable as described above. With the fan mounting frame 10 opened, it is extremely dangerous if the cooling fan 7 is rotating. However, the safety net is provided on the rear side of the cooling fan 7 as described above, but the net is not mounted on the front side of the cooling fan 7. Therefore, the fan mounting frame 10 is opened while the cooling fan 7 is rotating, or
If the fan mounting frame 10 is opened in an engine startable state and the fan mounting is mistakenly started, the risk of an object coming into contact with the cooling fan 7 becomes extremely large.

Conventionally, some engine start circuits employ a neutral safety circuit. This neutral safety circuit is a safety device that enables the engine to be started only when the shift lever is set to a neutral position, because if the engine is started with the shift lever being moved forward or backward, the vehicle suddenly starts moving and is dangerous. However, in this apparatus, no consideration is given to safety when the movable cooling fan is opened as described above.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide a drive device for a cooling fan which makes it possible to move a cooling fan of a radiator and does not pose a danger when the cooling fan is moved.

[0007]

Means for Solving the Problems, Functions and Effects In order to achieve the above object, a first invention of a cooling fan drive device according to the present invention comprises a working machine provided at a front portion of a vehicle body and In a driving device for a cooling fan of a construction machine having an engine 4, a radiator 5, and a cooling fan 7 for cooling the radiator 5, one end of a fan mounting frame 10 supporting the cooling fan 7 is connected to the radiator 5. To be opened and closed by a hinge 11 so that the fan mounting frame 1
Open / close detecting means 30 and 31 for detecting the opening / closing of the cooling fan 7 and the open / close detecting means 30 and 31 during rotation of the cooling fan 7.
Means for stopping rotation of the cooling fan 7 when it detects that the fan mounting frame 10 has been opened.
0 is provided.

According to the above construction, when the fan mounting frame is opened during rotation of the cooling fan, the fan rotation control means determines that the cooling fan has moved and stops the rotation of the cooling fan. Even when the fan mounting frame is opened for cleaning or the like, the cooling fan stops and safety is ensured.

According to a second aspect of the invention, based on the configuration of the first aspect, the cooling fan 7 is driven by a hydraulic motor 6 which is driven to rotate by a hydraulic pump connected to the engine 4, and the fan rotation control means 20 comprises The operation of the engine 4 is stopped when the open / close detection means 30, 31 detects that the fan mounting frame 10 is opened during the operation of the engine 4.

According to the above configuration, when the cooling fan is driven by the hydraulic motor driven in conjunction with the operation of the engine, the operation of the engine is stopped when the fan mounting frame is opened during the operation of the engine. Then, the cooling fan stops rotating. Thus, even if the fan mounting frame is opened for cleaning the rear surface of the radiator or the like, the cooling fan is stopped, so that safety is ensured.

According to a third aspect based on the configuration of the first aspect, the cooling fan 7 is driven by a hydraulic motor 6 which is driven to rotate by a hydraulic pump connected to the engine 4, and the fan rotation control means 20 comprises: The drive of the hydraulic motor 6 is stopped when the open / close detectors 30 and 31 detect that the fan mount frame 10 is opened during the operation of the engine 4.

According to the above configuration, when the cooling fan is driven by the hydraulic motor driven in conjunction with the operation of the engine, the hydraulic motor stops when the fan mounting frame is opened during the operation of the engine. Then, the cooling fan stops rotating. Thus, even if the fan mounting frame is opened for cleaning the rear surface of the radiator or the like, the cooling fan is stopped, so that safety is ensured.

According to a fourth aspect of the present invention, based on the configuration of the first aspect, the open / close detecting means 30 and 31 are provided with a fan-mout frame 10.
The output contact is opened when is opened, and the fan mounting frame 1
An open / close detection switch that closes the output contact when 0 is closed.

According to the above configuration, the output contact of the open / close detection switch for detecting the opening / closing of the fan mounting frame is opened when the fan mounting frame is opened and closed when the fan mounting frame is closed. Therefore, the open / close detection can be performed with a simple configuration, and a fail-safe circuit can be provided to ensure that the open / closed detection switch comes off or the wiring is disconnected. Can be higher.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a cooling fan driving device according to the present invention will be described below in detail with reference to FIGS. Here, the wheeled construction machine 1 shown in FIG. 6 will be described as an example machine.

FIG. 1 is a plan view showing a configuration example of a driving device for a movable cooling fan according to the present invention. In the figure, a radiator 5 is disposed behind an engine 4 disposed behind a vehicle body of the wheeled construction machine, and a cooling fan is sandwiched between fan shrouds 8 attached behind the radiator 5. 7 are arranged. The hydraulic motor 6 that rotationally drives the cooling fan 7 is attached to the fan mounting frame 10. A safety net 12 is provided behind the cooling fan 7 of the fan mounting frame 10 so as to cover the cooling fan 7. One end (the right end in FIG. 1) of the fan mounting frame 10 is attached to the fan shroud 8 via a hinge 11 so as to be freely opened and closed.
Open / close detecting means 30, 31 for detecting opening / closing of the fan mounting frame 10 are attached near the hinge 11, and detection signals of the open / close detecting means 30, 31 are inputted to a fan rotation control means described later. ing. In the present embodiment, the open / close detecting means 30 and 31 are constituted by open / close detection switches such as limit switches (hereinafter referred to as first and second open / close switches 30 and 31), and the fan mount frame 10 is represented by a solid line. When closed as shown, the first and second open / close switches 3
The output contacts 0 and 31 are closed, and the output contacts of the first and second open / close switches 30 and 31 are opened when the fan mount frame 10 is opened as shown by a thin two-dot chain line.

FIG. 2 is an example of a circuit diagram of the fan rotation control means 20 of the driving device for the cooling fan according to the first embodiment. In FIG. 1, the fan rotation control means 20 has a neutral relay 22, a stop relay 24, an engine stop motor 25, and an engine starter motor 26. The terminal B of the starter switch 27 is connected to the battery 21 via a fuse. Starter switch 27
Is connected to the output terminal of the A contact 22a of the neutral relay 22 via the first open / close switch 30. The common terminal of the A contact 22 a of the neutral relay 22 is connected to one input terminal S of the engine starter motor 26. The positive terminal of the coil 22L of the neutral relay 22 is connected to the neutral terminal N of the shift lever switch 23, and the shift lever switch 23
Output common terminal D is the terminal BR of the starter switch 27.
It is connected to the. Further, the terminal BR of the starter switch 27 is connected to the positive terminal of the coil 24L of the stop relay 24 via the second open / close switch 31. Output terminal of B contact 24b of stop relay 24, A contact 24
The output terminal a and the output common terminal 24C are connected to the terminals P1, P2 and A1 of the engine stop motor 25, respectively. The engine stop motor 2
5, a negative terminal of the coil 24L of the stop relay 24, a negative terminal of the coil 22L of the neutral relay 22, and a terminal E of the engine starter motor 26 are grounded (connected to the negative terminal of the battery 21).

The starter switch 27 is a switch for starting the engine. When this switch is in the “OFF (off)” position, terminals B and C and terminals B and BR are open,
At the “START (start)” position, the terminals B and C and the terminals B and BR are both connected, and at the “ON (on)” position, the terminals B and C are open and the terminals B and C are open. The connection state is established only between the BRs.

The engine stop motor 25 is connected by a wire or the like to a stop lever for controlling the fuel injection amount of the engine. By pulling or returning the stop lever, the engine can be started or stopped. Or let it. The engine stop motor 25 is internally provided with the rotation of its motor shaft.
It has a contact function that cuts off current at every 0 degree rotation.
The battery power supply voltage applied to the terminal is output to either the terminal P1 or the terminal P2 via the contact function. An armature of a built-in motor is connected between the terminals A1 and A2, and when a voltage is applied between both terminals, the engine stop motor 25 starts rotating. Each time the motor shaft rotates 180 degrees, the voltage output to the terminal P1 or the terminal P2 is cut off by the contact function.

Next, the operation will be described. FIG. 3 is an explanatory diagram showing the operation of the fan rotation control means of the present embodiment. First, a starting safety circuit will be described with reference to FIG. 2 based on this drawing. FIG. 2 shows a state in which the speed change lever switch 23 is set to neutral N, the fan mount frame 10 is closed, and the first and second open / close switches 30 and 31 are closed. In this state, set the starter switch 27 to "OF
In the position "F", since the power supply voltage is not applied to the engine starter motor 26, the engine starter motor 26 does not operate and the engine 4 does not start.

Next, the starter switch 27 is turned on.
(ON) position, the coil 24L of the stop relay 24 is connected between the terminals B and BR and via the second open / close switch 31.
Excitation current flows through the A contact 24a of the stop relay 24
Turns on. Thereby, the engine stop motor 25
Is connected between the terminal A1 and the terminal P2, the power supply voltage applied to the terminal Q is applied to the engine stop motor via the contact function built into the engine stop motor 25, the terminal P2, and the A contact 24a of the stop relay 24. The current is applied to the terminal A1 of the motor 25, and a current flows through the armature of the engine stop motor 25. Then, the engine stop motor 25 rotates in a predetermined direction and pulls the stop lever through a wire or the like. When the stop lever rotates 180 degrees, that is, when the stop lever is pulled a predetermined distance, the power supply voltage output from the terminal P2 is cut off to rotate. Stop. Therefore, a fuel injection pump (not shown) is in a fuel supply state, and the engine is in a startable state.

The coil 2 of the neutral relay 22 passes from the battery 21 through the terminals B and BR of the starter switch 27 and between the terminals DN of the shift lever switch 23.
Current flows through 2L. As a result, the A contact 22a of the neutral relay 22 is turned on.

In this state, the starter switch 27 is set to "STAR
When the switch is in the "T" position, the terminals BB of the starter switch 27 are
The connection state is maintained between R and the terminals B and C are connected. Thus, the current from the battery 21 flows to the engine starter motor 26 between the terminals BC of the starter switch 27, the first open / close switch 30 and the A contact 22a of the neutral relay 22, and the engine starter motor 26 rotates. The engine 4 is started. When the shift lever switch 23 is set at the forward F position or the reverse R position other than the neutral N position, the coil 2 of the neutral relay 22 is turned off.
Since 2L is not excited, the starter motor 26 does not start. That is, the engine can be started only when the shift lever switch 23 is set to the neutral N position, and safety at the time of starting is ensured.

Further, the shift lever switch 23 is set to a neutral N
When the fan mounting frame 10 is opened in the state where
The output contact of the first open / close switch 30 opens. Therefore,
Since the power supply voltage is not applied to the engine starter motor 26 even if the starter switch 27 is set to the "START" position,
The starter motor 26 does not start, so that the engine cannot be started, and safety is ensured.

Next, the operation of the emergency stop circuit will be described. After the engine is started by the starter switch 27, when the starter switch 27 is returned to the “ON” position, the connection between the terminals B and BR is maintained. At this time, when the fan mounting frame 10 is closed, the output contact of the second open / close switch 31 is closed.
4, the A contact 24a remains closed and the B contact 24b remains open, whereby the engine stop motor 25 maintains the starting position and the engine continues to operate.

As described above, in the engine operating state,
When the fan mounting frame 10 is opened for any reason, the output contact of the second open / close switch 31 is opened and the coil 24L of the stop relay 24 is not excited.
4a opens and the B contact 24b closes. Therefore, the terminal A1 of the engine stop motor 25 is now connected to the terminal P1, so that the terminal A1 of the engine stop motor 25 has a terminal Q, the contact function built in the engine stop motor 25, a terminal P1, and a stop. A power supply voltage is applied via a B contact 24b of the relay 24. As a result, the engine stop motor 25 rotates in a predetermined direction,
When the stop lever is returned to its original state via a wire (due to the return force of a spring (not shown) attached to the stop lever portion) and turned 180 degrees, that is, when the stop lever is returned to the position at the time of engine stop, from the terminal P1. The output power supply voltage is cut off and rotation stops. For this reason, the fuel injection pump (not shown) stops the fuel supply, and the engine is stopped immediately. Therefore, the fan mounting frame 10
The engine will no longer run with the
Safety is ensured.

As described above, the fan mounting frame 10
When the switch is opened, the first and second open / close switches 30 and 31 are opened, thereby making it impossible to start the engine and stopping the engine even during operation, thereby ensuring safety. In this embodiment, the engine stop motor 25
However, the present invention is not limited to this, and the operation of the stop lever for a predetermined distance may be controlled by, for example, a solenoid.

FIG. 4 is an example of a circuit diagram of the fan rotation control means of the second embodiment. The description of the same parts as those in the first embodiment will be omitted, and only different parts will be described. In this embodiment, instead of the output contacts of the first and second on / off switches 30 and 31 in the previous embodiment, an on / off detection open / close detection relay 32 operated by the first on / off switch 30 is used.
The circuit is configured using the two A contacts. That is,
The positive terminal of the coil 32L of the open / close detection relay 32 and the positive terminal of the battery 21 are connected via a fuse and the first open / close switch 30, and the A contact 32a1 and the A contact 32a2 of the open / close detection relay 32 are each a diagram of the previous embodiment. 2 are connected to the same connection points as the first and second open / close switches 30 and 31. The first open / close switch 30 is attached to the fan mount frame 10 as shown in FIG. 1 as in the previous embodiment, and when the fan mount frame 10 is closed, the first open / close switch 30 is closed. The output contact is closed, and when the fan mount frame 10 is opened, the output contact of the first open / close switch 30 is opened.

Next, the operation will be described. When the fan mounting frame 10 is closed, the first open / close switch 30 is closed, so that the coil 32L of the open / close detection relay 32 is excited, and the A contact 32a1 and the A contact 32a2
Are on. When the starter switch 27 is set to “OF
When in the position "F", since the terminals B and BR are open, the power supply voltage is not applied to the engine starter motor 26, and the engine 4 does not start. Next, when the shift lever switch 23 is set to the neutral position N and the starter switch 27 is set to the "ON" position, the coil 24L of the stop relay 24 is connected between the terminals B and BR and via the A contact 32a2 of the open / close detection relay 32. , An exciting current flows, and the A contact 24a of the stop relay 24 turns on. Thus, as described above, the engine stop motor 25 rotates in a predetermined direction to pull the stop lever of the fuel injection pump, and when the stop lever is pulled a predetermined distance, the power supply voltage output from the terminal P2 is cut off and the rotation stops. Therefore, a fuel injection pump (not shown) is in a fuel supply state, and the engine is in a startable state. Also, an exciting current flows from the battery 21 to the coil 22L of the neutral relay 22 via the terminals B and BR of the starter switch 27 and the terminals DN of the shift lever switch 23, and the A of the neutral relay 22
The contact 22a turns on.

In this state, the starter switch 27 is set to "STAR
When the switch is in the "T" position, the terminals BB of the starter switch 27 are
The connection state is maintained between R and the terminals B and C are connected. Thereby, the terminals BC of the starter switch 27
During this time, the power supply voltage is applied to the engine starter motor 26 via the A contact 32a1 of the open / close detection relay 32 and the A contact 22a of the neutral relay 22, and the engine starter motor 26 rotates to start the engine 4. When the shift lever switch 23 is in the forward F position or the reverse R position other than the neutral position N, the coil 22L of the neutral relay 22 is not excited, and the starter motor 26 does not start. That is, the shift lever switch 23 is set to the neutral N
The engine can be started only when it is in the position, and safety at the time of starting is ensured.

When the fan mount frame 10 is opened,
The first open / close switch 30 is opened, the coil 32L of the open / close detection relay 32 is not excited, and the A contact 32a1 and the A contact 32
a2 turns off. Therefore, the engine starter motor 2
6, the engine cannot be started, and the terminal A1 of the engine stop motor 25 cannot be started.
And the terminal P1 is connected, so that the running engine is also stopped. Thereby, safety is ensured.

FIG. 5 is an example of a circuit diagram of the fan rotation control means of the third embodiment. Pressure oil is supplied from a hydraulic pump 40 to a hydraulic motor 6 that drives the cooling fan 7 via a discharge circuit 41. On the discharge circuit 41, an electromagnetic switching valve 42 is interposed. The electromagnetic switching valve 42 has an A position and a B position. At the A position, the discharge circuit 41 of the hydraulic pump 40 communicates with the drain circuit 43, and the pressure oil from the hydraulic pump 40 is drained to the oil tank 44. At the position B, the discharge circuit 41 communicates with the hydraulic motor 6 and drives the hydraulic motor 6. The solenoid operating portion of the electromagnetic switching valve 42 is connected to the battery 21 via the first opening / closing switch 30, and the electromagnetic switching valve 42 switches between the position A and the position B by opening / closing the first opening / closing switch 30.

Next, the operation will be described. When the fan mounting frame 10 is closed, the first open / close switch 3
Since the output contact 0 is closed, the electromagnetic switching valve 42 is switched to the position B as shown in FIG. 5, and the hydraulic oil discharged from the hydraulic pump 40 is supplied to the hydraulic motor 6 to rotate the cooling fan 7. . When the fan mounting frame 10 is opened,
The first open / close switch 30 opens, and the electromagnetic switching valve 42 switches to the A position. Thus, the discharge circuit 41 of the hydraulic pump 40 communicates with the drain circuit 43, and the pressure oil is supplied to the oil tank 4
Drain to 4. Therefore, the hydraulic motor 6 stops, and the rotation of the cooling fan 7 stops. Therefore, safety is ensured.

In the embodiment described above, the fan rotation control means 20 is provided with a relay circuit and an engine control device (an engine stop motor 25 and an engine starter motor 26) or a fan drive hydraulic device (an electromagnetic switching valve 4).
2), but the present invention is not limited to this. That is, when the movement of the cooling fan 7 is detected,
The cooling fan 7 may be stopped. For example, the fan rotation control means 20 may be configured by an electronic circuit or the like, and the cooling fan may be driven by an electric motor to directly control the driving and stopping of the electric motor. Further, the open / close detecting means 30, 31 is not limited to the limit switch, that is, any means may be used as long as it can detect the movement (open / close) of the cooling fan, and may be, for example, a proximity switch, a pressure switch, a photoelectric switch, a distance detection sensor, or the like.

[Brief description of the drawings]

FIG. 1 is a plan view of a configuration example of a cooling fan drive device according to the present invention.

FIG. 2 is a circuit diagram example of a fan rotation control unit according to the first embodiment of the present invention.

FIG. 3 is an operation table of a fan rotation control unit of the first embodiment.

FIG. 4 is an example of a circuit diagram of a fan rotation control unit according to a second embodiment of the present invention.

FIG. 5 is an example of a circuit diagram of a fan rotation control unit according to a third embodiment of the present invention.

FIG. 6 is a side view of the wheeled construction machine.

[Explanation of symbols]

 Reference Signs List 4 engine 5 radiator 6 hydraulic motor 7 cooling fan 10 frame for fan mounting 11 hinge 20 fan rotation control means 21 battery 22 neutral relay 23 shift lever 24 stop relay 25 engine stop motor 26 starter motor 27 starter switch 30 first open / close switch 31 Second open / close switch 32 Open / close detection relay 40 Hydraulic pump 41 Discharge circuit 42 Electromagnetic switching valve

Claims (4)

[Claims] 1. A work machine provided at a front part of a vehicle body, an engine (4) and a radiator (5) provided at a rear part, and a radiator
In a driving device for a cooling fan of a construction machine having a cooling fan (7) for cooling (5), one end of a fan mounting frame (10) supporting the cooling fan (7) is connected to the radiator (5). Opening / closing detection means (30, 31) for opening and closing by the hinge (11) and detecting opening / closing of the fan mounting frame (10) are provided, and opening / closing detection means (30) during rotation of the cooling fan (7). 30,31) is the frame for fan mounting
A driving device for a cooling fan, comprising: fan rotation control means (20) for stopping rotation of the cooling fan (7) when detecting that the (10) is opened. 2. The cooling fan drive according to claim 1, wherein the cooling fan is driven by a hydraulic motor rotatably driven by a hydraulic pump connected to an engine, and the fan is driven by the hydraulic pump. The rotation control means (20) stops the operation of the engine (4) when the open / close detection means (30, 31) detects that the fan mounting frame (10) has been opened during the operation of the engine (4). A cooling fan driving device characterized by the above-mentioned. 3. The cooling fan drive according to claim 1, wherein the cooling fan is driven by a hydraulic motor rotatably driven by a hydraulic pump connected to an engine, and the fan is driven by the hydraulic motor. The rotation control means (20) stops driving of the hydraulic motor (6) when the open / close detection means (30, 31) detects that the fan mounting frame (10) is opened during operation of the engine (4). A driving device for a cooling fan, characterized in that: 4. The cooling fan driving device according to claim 1, wherein said opening / closing detecting means (30, 31) comprises a fan-mout frame (10).
The output contacts open when the fan opens, and the fan mounting frame (1
A drive device for a cooling fan, wherein the drive device is an open / close detection switch that closes an output contact when 0) is closed.