JPH0452086Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a vehicle suspension spring locking device suitable for locking a suspension spring of a vehicle having a crane driver's seat and a carrier driver's seat.

[Conventional technology]

In a vehicle such as a crane truck, a crane driver's seat for easy crane operation is provided in addition to a carrier driver's seat for driving the vehicle.

However, conventional crane trucks were configured in such a way that the driver's seat for operating the crane could not be used to operate the vehicle, making it difficult to use crane trucks to transport materials over short distances at construction sites. If the driver had to go back and forth many times, he would have to go up and down between the two cabs each time, which was extremely troublesome.

In order to solve this problem, a crane truck has been proposed in which the driver's seat for operating the crane can also be used to drive the vehicle.

In addition, in order to be able to lift loads without using the on-tires of the crane vehicle, that is, without using the outriggers that extend out to secure the vehicle body, suspension springs are interposed between the vehicle body and each axle, and suspension springs are installed between the vehicle body and each axle. A device in which a suspension spring is locked or unlocked by the operation of an interposed hydraulic cylinder has been proposed, for example, in Japanese Utility Model Publication No. 57-36492.

However, if the driver forgets to unlock the suspension springs when transferring from the crane driver's seat to the carrier driver's seat for general driving, a problem arises in that handling stability and riding comfort are significantly impaired. Therefore, it is possible to unlock the suspension springs from the carrier driver's seat, but since it is difficult to check whether a load is being suspended from the carrier driver's seat for general driving, it is difficult to confirm whether the load is being lifted or not, so if the load is suspended on the tires due to carelessness, There is a possibility of unlocking operation. This significantly reduces the stability of the vehicle body and is dangerous. For this reason, the switch for locking and unlocking the suspension springs should be installed only in the crane driver's seat, and if the suspension springs are not unlocked by the hydraulic system, this should be notified to the driver in the carrier driver's seat when the crane is about to drive. There was a demand for something that could do that.

[The problem that the idea attempts to solve]

The present invention was devised in view of the above-mentioned conventional problems, and its purpose is to provide a suspension spring for a vehicle that can prevent the suspension spring from remaining locked during general driving. The purpose of this invention is to provide a locking device for

[Means to solve the problem]

To achieve the above object, the present invention provides a vehicle having a crane driver's seat and a carrier driver's seat, and a suspension spring interposed between the vehicle body and the axle. A hydraulic system that locks or unlocks the spring, an alarm that issues an alarm in the carrier driver's seat when the main power switch of the carrier driver's seat is activated with the suspension spring locked, and a main power source for one driver's seat. It is characterized by having a cancel relay that disables the operation of the main power switch on the other driver's seat when the switch is turned on, and a cutoff circuit that cuts off the drive loop of the alarm when the hydraulic system is unlocked. .

[Effect]

If the alarm drive loop is cut off when the switch that unlocks the suspension spring is operated in the crane operator's seat, the suspension spring will remain locked depending on the operating state of the alarm in the carrier driver's seat. You can check whether or not.

〔Example〕

Hereinafter, preferred embodiments of the present invention will be described based on the drawings.

FIG. 1 shows the configuration of a preferred embodiment of the present invention. In the figure, hydraulic cylinders 10 and 12 for the front wheels and hydraulic cylinders 14 and 16 for the rear wheels are connected to the vehicle body 18 shown in FIG. 2 and the front axle 2, respectively.
0, it is interposed between the rear wheel 22 and the rear wheel 22. Piston rods 10a, 12a, 14a, 16a are slidably inserted into each hydraulic cylinder 10, 12, 14, 16, and each piston 10a to 16a is pivotally connected to a front shaft 20 and a rear wheel 22, respectively. It is connected to piston rods 10b, 12b, 14b, and 16b. The cylinder chambers 10c, 12c, 14c, 16c of each hydraulic cylinder 10a-16a are connected to a lock switching valve 28 via a pilot check valve 25 and a pipe 26. and,
The pipe 26 is selectively connected to a tank 30 or a pump 32 by operating a lock switching valve 28. Further, each pilot check valve 25 closes the cylinder chambers 10c, 1 when pilot pressure is applied through the pilot pressure introduction pipe 34.
Lock switching valve 2 from 2c, 14c, 16c
It is designed to allow hydraulic oil to flow out to 8. Further, the pilot pressure introduction pipe 34 is connected to a switching valve 36 for releasing the lock, and is selectively connected to a tank 38 or a pump 40 by operating the switching valve 36 for releasing the lock. In addition, the cylinder chambers 10d, 12d, 14d,
16d are each open to the atmosphere.

Each hydraulic cylinder 10-16 is typically a pump 40
The pilot pressure introduction pipe 34 is connected to the tank 30, and the pilot check valve 25 is opened.
and the pipe 26 are connected, that is, the cylinder chamber 1
0c, 12c, 14c, and 16c are used in communication with the tank 30. When lifting a load on-tire, the lock release switching valve 36 is operated to communicate the pilot pressure introduction pipe 34 with the tank 38, thereby opening the cylinder chamber 10.
c, 12c, 14c, and 16c, and operate the lock switching valve 28 to connect the pipe 26 and the pump 32.
This allows the hydraulic oil to flow into each cylinder chamber 10c to 16c.
The hydraulic cylinders 10 to 16 are contracted, and the vehicle body 18 and the axle 2 are connected to each other, as shown in FIG.
The suspension spring 42 interposed between the two is configured to be locked.

Each switching valve 28, 36 is connected to the crane driver's seat 1.
3 and a signal from the circuit 50.

The drive circuit 50 includes a battery relay 54, a cancel relay 56, a key switch 58, a lock release switch 60, a lock switch 62, etc. The battery relay 54 and key switch 58 are supplied with current from a generator 64 and a battery 66. Further, the lock release switch 60 is connected to the lock release switching valve 36, and the lock switch 62 is connected to the lock switching valve 28.

On the other hand, the drive circuit 52 of the carrier driver's seat 11 is composed of a battery relay 68, a cancel relay 70, a key switch 72, an alarm lamp 74, a contact 76, a coil 78, etc., and the battery relay 68 and key switch 72 are connected to the battery 66. has been done. The coil 78 is connected to the lock release switch 60 and the lock release switching valve 36. In addition, 75 is an alarm drive loop, 79
is a cutoff circuit for the alarm drive loop 75, and 80 and 81 are diodes, respectively.

In the above configuration, when the key switch 72, which is the main power switch of the carrier driver's seat 11, is turned on while the key switch 58 of the crane operator's seat 13 is in the OFF state, the coil 68b is energized, the contact 68a is closed, and the alarm lamp 74 is turned on. Light. At this time, the coil 56b of the cancel relay 56 is also excited and the contact 56a is opened, so even if the key switch 58 of the crane driver's seat 13 is turned on, the drive circuit 50 is not activated.

Next, after turning off the key switch 72, move to the crane driver's seat 13 and turn on the key switch 58, the coil 54b is energized and the contact 54a is turned on.
closes. At this time, if the lock switch 62 is turned on, the power of the battery 66 is supplied to the lock switching valve 28, and the lock switching valve 28 is turned on.
The suspension spring 42 is locked by this operation. Note that at this time, the coil 70b is energized and the contact 7
0a is open, the carrier drive circuit 52 will not be turned on even if the key switch 72 of the carrier driver's seat 11 is turned on.

Next, switch the key switch 5 of the crane driver's seat 13.
8 to turn off the lock switch 62, and then turn the key switch 72 of the carrier driver's seat 11 while keeping the lock release switch 60 turned on.
Even if the switch is turned on, the power of the battery 66 is supplied to the lock release switching valve 36, and the suspension spring 42 is brought into the unlocked state. At this time, the coil 78 is energized and the contact 76 is connected to the drive loop 7 of the alarm lamp 74.
5, the alarm lamp 74 will not light up. Therefore, when shifting from crane operation to general traveling operation, it is possible to check whether the suspension spring 62 remains locked or has been unlocked by checking whether the warning lamp is lit or not.

Then, when you turn off the key switch 58 in the crane driver's seat 13 to lock the suspension spring 42, go to the carrier driver's seat 11, turn on the key switch 72, and try to drive normally, the warning lamp 74 lights up. At the same time, the cancel relay 56 in the crane driver's seat 13 is turned off. As a result, the battery relay 54 is also turned off, and the supply of power to the drive circuit 50 of the crane driver's seat 13 is cut off. The operator then learned that the suspension spring 42 was locked, returned to the crane driver's seat 13, turned off the lock switch 62, and
When the lock release switch 60 is turned on, the diode 8 is removed from the drive circuit 52 of the carrier driver's seat 11.
Since power is supplied to the circuit of the lock release switch 60 through 0, the lock release switching valve 36
is activated and the unlock operation is performed. At the same time, the coil 78 is energized, the contact 76 is opened, and the alarm lamp 74 is turned off. Therefore, the driver can drive normally by confirming that the warning lamp 74 is turned off on the side of the carrier driver's seat 11.

[Effect of idea]

As explained above, according to the present invention, when the switch for unlocking the suspension spring is operated in the crane driver's seat, the alarm drive loop is cut off, so the alarm can be activated in the carrier driver's seat. Depending on the condition, it can be determined whether the suspension spring remains locked. Therefore, an excellent effect can be obtained in that it is possible to prevent the vehicle from driving normally with the suspension springs locked.

[Brief explanation of the drawing]

Fig. 1 is a circuit diagram of a locking device showing an embodiment of the present invention, Fig. 2 is a side view of a crane truck, and Fig. 3 is a side view of a crane truck.
The figure is a rear view of the crane truck. 10, 12, 14, 16...hydraulic cylinder, 1
1... Carrier driver's seat, 13... Crane driver's seat, 28... Lock switching valve, 36... Lock release switching valve, 42... Suspension spring, 5
0, 52... Drive circuit, 56, 70... Cancel relay, 58, 72... Key switch, 74...
...Alarm lamp, 75...Alarm drive loop, 79...
...A cutoff circuit for the alarm drive loop 75.

Claims (1)

[Scope of utility model registration request] In a vehicle having a crane driver's seat and a carrier driver's seat, and a suspension spring interposed between the vehicle body and the axle, a hydraulic system for locking or unlocking the suspension spring according to the operation of the crane driver's seat; When the main power switch on the carrier driver's seat is activated with the spring locked, there is an alarm in the carrier driver's seat that sounds an alarm, and when the main power switch on one driver's seat is turned on, the alarm on the other driver's seat is activated. 1. A locking device for a suspension spring for a vehicle, comprising a cancel relay that disables operation of a main power switch of the vehicle, and a cutoff circuit that cuts off a drive loop of an alarm when a hydraulic system is unlocked.