JPH09136672A - Cab tilt device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cab tilt device, which can tilt a cab in the condition that a door is perfectly closed or the door is perfectly opened. SOLUTION: A cab lock switch 10, which is normally opened and which is closed at the time of releasing the lock of a cab, a first door switch 11, which is normally opened and which is closed at the time of full closing the door of the cab, a second door switch 12, which is normally opened and which is closed at the time of full closing the door, are provided in a motor 9 driving circuit, and the motor 9 is driven when the cab lock switch 10 is closed and the first door switch 11 or the second door switch 12 is closed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cab overt device for a cab over engine type vehicle.

[0002]

2. Description of the Related Art Conventionally, there is known a cab tilting device for tilting a cab by a hydraulic cylinder operated by an electric motor driven hydraulic pump. With this device, the cab can be easily tilted by operating the tilt lever, but since the tilt is performed regardless of whether the door is open or closed, the tilt lever is operated while the door is not locked. Then, there is a problem that the door opens during tilting.

Therefore, there is a technique in which a door switch for detecting the fully closed state of the door is provided so that the cab cannot be tilted unless the door is completely closed.
It is disclosed in Japanese Patent No. 51172.

[0004]

However, in the tilted state of the cab, it may be desirable that the door is opened, for example, when the engine is started, for convenience of maintenance. There is a problem that opening the door in a tilted state of the cab requires a certain degree of familiarity, and if the door is opened in an unfamiliar state, the door suddenly opens.

An object of the present invention is to solve the above problems and to provide a cab tilting device capable of tilting the cab when the door is completely closed or when the door is completely open.

[0006]

According to the first aspect of the present invention,
In a cab tilt device that tilts a cab with a hydraulic cylinder operated by an electric motor-driven hydraulic pump, a normally open cab lock switch that closes when the cab is unlocked, and a normally open first door that closes when the cab door is fully closed. A switch and a normally open second door switch that closes when the door is fully opened are provided in the drive circuit of the electric motor, the cabling switch is closed, and the first door switch or the second door switch is closed. The electric motor is driven only when.

According to a second aspect of the present invention, there is provided the cavitt apparatus according to the first aspect, further comprising an alarm device which is activated when the electric motor is inoperative, the cablock switch is closed, and the first door is provided. The alarm device is operated when the switch and the second door switch are open.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a cab-over engine type vehicle adopting an embodiment of the present invention. In the figure,
The cab 2 of the cab-over engine type vehicle 1 is normally locked to the chassis 7 by a lock mechanism (not shown) during traveling.

An engine 3, a hydraulic cylinder 4, a hydraulic pump 5, an operating lever 6 and the like are arranged below the cab 2.

The hydraulic cylinder 4 tilts the cab 2 by receiving the hydraulic pressure and extending the rod. A holding mechanism (not shown) is provided in the vicinity of the hydraulic cylinder 4 so that the cab 2 does not descend even if the hydraulic cylinder 4 should fail during tilting. It has, and when this motor 9 is energized, hydraulic pressure is generated. Operating lever 6
Is manually operated by an operator, and by operating this, the lock state between the cab 2 and the chassis 7 is released, and then the hydraulic pump 5 is operated to raise or lower the cab 2. The operating lever 6 is provided with a normally open cab lock switch 10 that is closed when the locked state between the cab 2 and the chassis 7 is released.

Further, doors 8 and 8 (only one of which is shown) arranged on both sides of the cab 2 are provided with a normally open first door switch 11 which is closed when the doors 8 and 8 are fully closed, and each door. 8,
There is provided a normally open second door switch 12 which is closed when 8 is fully opened. The fully closed state here means that the door is completely closed, and the fully opened state means that the door is completely open and does not move in the opening direction.

FIG. 2 is a diagram showing a drive circuit of the motor 9 for driving the hydraulic pump 5. In FIG.
Reference numeral 3 is a power source, reference numeral 14 is a fuse, reference numeral 15 is a fuse and relay box, and reference numeral 16 is a relay.

In this drive circuit, the power supply 13 and one contact of the relay 16 having an a-contact are connected in series via the fuse 14, and the exciting coil of the relay 16 is connected via the fuse and relay box 15 to Cab block switch 10 and first door switch 11 connected in parallel
And the second door switch 12 are connected. Also,
The other contact of the relay 16 is connected to the motor 9.

With the above configuration, when the vehicle 1 is normally traveling, the drive circuit of the motor 9 is in the state shown in FIG. 2, that is, the cab lock switch 10 is open, the first door switch 11 is closed, and the second door switch is closed. 12 open, relay 16
Is off, and the motor 9 is stopped.

When the cab 2 is tilted from the state shown in FIG. 2, the actuating lever 6 is tilted upward. As a result, the lock state between the cab 2 and the chassis 7 is released, the cab lock switch 10 is closed, the relay 16 is turned on, the motor 9 is operated, the hydraulic pump 5 is driven, and the hydraulic cylinder 4 is operated. The cab 2 is tilted as shown in FIG.

When it is desired to start the engine 3 after tilting for convenience of maintenance, tilting is performed with the doors 8, 8 fully opened in advance. In this case, the first door switch 11 is opened, the second door switch 12 is closed, and the cab 2 is tilted by closing the cab lock switch 10 by tilting the operating lever 6 upward.

At the time of tilting, when at least one of the doors 8 and 8 is a half door or when one door 8 is closed and the other door 8 is open, etc., the first door switch 11 and the first door switch 11 Since both of the two-door switches 12 are opened, the relay 16 is not turned on even when the cab lock switch 10 is closed, and the motor 9 and the hydraulic pump 5 are not driven, so that the tilt is not performed.

FIG. 3 is a diagram showing a modification of the drive circuit of the motor 9. Compared with the above-mentioned embodiment, this modification is different in that a relay 17 and a buzzer 18 as an alarm device are added, and other configurations are the same.

One contact of the relay 17 having a b-contact is connected to the cabling switch 10 and the other contact is connected to the buzzer 18. The exciting coil of the relay 16 is connected to the first door switch 11 and the second door switch 12 which are connected in parallel.

In this modification, when the doors 8 and 8 are tilted with the doors 8 and 8 fully opened or fully closed as in the above-described embodiment, the first door switch 11 or the second door switch 12 is closed. Cablock switch 1 in the state
Since 0 is closed, the cab 2 is tilted. At this time, the first door switch 11 or the second door switch 12
A current flows through the exciting coil of the relay 17 via the, and the exciting coil is attracted to separate the contacts of the relay 17 from each other.

Further, in the above modification, when both the first door switch 11 and the second door switch 12 are opened as described above, tilting is not performed as in the above embodiment, and the relay 17 is used. Since no current flows through the exciting coil and each contact of the relay 17 is connected, the buzzer 18 operates and issues an alarm.

[0022]

According to the present invention, the cab can be tilted only when the door is completely closed or when the door is completely open. Therefore, the cab can be tilted when the door is not locked. The problem that the door opens during tilting due to the lever being operated is solved, and if it becomes necessary to open the door after tilting due to maintenance reasons, etc., it is caused by opening the door after tilting. It is possible to prevent the problem that the door suddenly opens. Further, when the user tries to tilt the door when the door is not completely closed or when the door is not completely opened, an alarm is issued and the operator can be alerted.

[Brief description of the drawings]

FIG. 1 is a schematic side view of a cabover engine type vehicle that employs an embodiment of the present invention.

FIG. 2 is a drive circuit diagram of a motor that drives a hydraulic pump according to an embodiment of the present invention.

FIG. 3 is a drive circuit diagram of a motor for driving a hydraulic pump showing a modified example of the embodiment of the present invention.

[Explanation of symbols]

 2 cab 4 hydraulic cylinder 5 hydraulic pump 8 door 9 motor 10 cab lock switch 11 first door switch 12 second door switch 18 alarm device (buzzer)

Claims (2)

[Claims] 1. A cab tilt device for tilting a cab by a hydraulic cylinder operated by a hydraulic pump driven by an electric motor, comprising a normally open cab lock switch which is closed when the cab is unlocked, and a normally closed cab lock which is closed when the cab door is fully closed. An open first door switch and a normally open second door switch that is closed when the door is fully opened are provided in the drive circuit of the electric motor, and the cabling switch is closed, and the first door switch or the second door. A cavitating device, wherein the electric motor is driven only when the switch is closed. 2. An alarm device which is activated when the electric motor is inactive, and activates the alarm device when the cab lock switch is closed and the first door switch and the second door switch are open. The cavitating device according to claim 1, wherein