JPS6353070B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to improvements in steering lock devices used in vehicles.

Generally, a caster-type steer rear axle is provided as the rearmost axle of a heavily loaded vehicle, such as a cargo truck, and is designed to reliably support the load of the truck.

Such a caster type steer rear axle is
Used in combination with a locking device, the driver can selectively operate the steer locking device to allow the caster type steer rear axle to move freely.
It has been placed in an axle state or a dead axle state.

Therefore, when the driver operates the steer lock device to the unlocked side, the caster-type steer rear axle is placed in a free axle state, causing significant wear on the tires attached to the caster-type steer rear axle. When the driver operates the steer lock device to the lock side, the caster type steer rear axle is placed in a dead axle state, making it possible for the truck to move backward stably. It has been designed so that it can be carried out under certain conditions.

However, such steering lock devices were operated manually by the driver;
Driving operations become complicated, and if the driver neglects to operate the steering lock device and attempts to reverse with the rear axle of the caster-type steerer in the free axle state, the caster-type steerer rear axle may There was a risk that the rear of the steering shaft would wobble, making it difficult to move backwards stably and reliably.

The purpose and problem of the present invention is to automatically lock and unlock the rear axle of a caster type steerer by using an electric circuit provided in the vehicle to notify the vehicle of the backward movement of the vehicle. When the vehicle is moving forward, the caster-type steered rear axle is automatically placed in a free axle state to prevent excessive tire wear and enable smooth turns, and when the vehicle is reversing, the caster-type steered rear axle is Automatically places the axle in a dead axle state to enable stable reversing, thereby also facilitating the driving operation of the vehicle, and making the entire device simple and inexpensive to manufacture, and To provide a steering lock device used in a vehicle which can be easily installed even in existing vehicles.

In connection with the above-mentioned objects and problems, the steer lock device used in the vehicle of the present invention places the caster-type steer rear axle in a free axle state when the vehicle is moved forward, and when the vehicle is moved backward. a hydraulic steer lock cylinder that places the shaft in a dead axle condition when the axle is turned, and an electromagnetic lock valve disposed in a hydraulic line connecting the steer lock cylinder to a source of fluid pressure; The lock valve includes a back-up switch electrically connected to the electric circuit of the lock valve.

Hereinafter, preferred specific examples of the steering lock device used in a vehicle according to the present invention will be described with reference to the drawings.

1 and 2 schematically show a specific example 10 of a steering lock device used in a vehicle of the present invention applied to a rear two-axle type truck.

The steer lock device 10 includes a pair of pneumatic steer lock cylinders 11 and 12 disposed on the chassis frame side of the truck for a caster type steer axle as the rear axle of the rear two-axle type truck. and pneumatic piping 13 connecting the steer lock cylinders 11, 12 to a pneumatic source.
It consists of an electromagnetic lock valve 14 disposed in the lock valve 14, and a back-up switch 22 electrically connected to the electric circuit of the lock valve 14. That is, in a two-axle type truck, the rear and front axles are driven by an engine mounted on the truck, and the rear axle is configured as a caster type steer rear axle. In order to notify that the truck is reversing, the back up switch 22 of the reversing warning device provided in the truck is used.
Automatically places its caster-type steer rear axle in a free axle condition when the truck is advanced, and automatically places its caster-type steer axle rear axle in a dead axle condition when the truck is reversed. It was designed to be placed on the target.

The steer lock cylinders 11 and 12 are
A pneumatic cylinder consisting of a cylinder, a piston fitted into the cylinder bore of the cylinder so that it can slide back and forth, and a push rod whose one end can be taken in and out of the cylinder and whose other end is connected to the piston. It has been done.

The steer lock cylinders 11 and 12 are
They are respectively disposed on the chassis frame side at the rear of the truck, and each push rod end is connected to the caster type steer rear axle side.

Therefore, the steer lock cylinder 11,
When compressed air is not being delivered to 12, its piston and push rod slide back and forth with the movement of its caster-type steer rear axle, and its caster-type steer rear axle is placed in a free axle condition. , and the steer lock cylinder 1
When compressed air is being delivered to 1 and 12, their pistons and push rods are held in place and their caster-type steer rear axles are placed in a dead axle condition.

The steer lock cylinders 11 and 12 are
It is connected via a pneumatic line 13 to an air tank attached to the chassis frame of the truck.

The solenoid lock valve 14 has a pressure port 15, a cylinder port, and an exhaust port 17.
A three-way control solenoid valve with an electric circuit, i.e., a current flowing through the solenoid coil, to connect its pressure port 15 to its cylinder port, and
the cylinder port 16 to the exhaust port 17
The steering lock cylinders 11, 12 are arranged in pneumatic piping 13 connecting the steer lock cylinders 11, 12 and the air tank.

Of course, when the lock valve 14 is installed in the pneumatic line 13, the pressure port 15 is connected to the air tank side and the cylinder port 16 is connected to the air tank side.
are connected to the steer lock cylinders 11 and 12, respectively.

Therefore, when the solenoid coil of the lock valve 14 is not energized, the cylinder port 16 is connected to the exhaust port 17 and the steer lock cylinder 11,
When the compressed air in 12 is exhausted, the caster-type steer rear axle is placed in a free axle condition, and the solenoid coil is energized with current, the pressure port 15 is connected to the cylinder.・Connected to port 16, compressed air is sent to the steer lock cylinders 11, 12,
The caster type steer rear axle is held in a dead axle condition.

Further, the lock valve 14 is not only operated manually by the driver of the truck, but also automatically operated in conjunction with the truck's reverse warning device. It is connected to an electric circuit that also serves as a back-up switch 22 of the notification device.

That is, the electrical circuit for the lock valve 14 includes an automatic and manual transfer switch 20;
A manual steer lock circuit 18 includes a normally closed steer lock release switch 21 connected in series to the switch 20, and a manual steer lock circuit 18 that connects the solenoid coil of the lock valve 14 to a battery 27. That is, the truck has a back up switch 22, a back up buzzer 23 and a back up lamp 24 connected to the back up switch 22 in parallel with each other for automatic and manual switching. The automatic steer lock circuit 19 connects the automatic side contact of the switch 20 to its battery 27.

In the manual steer lock circuit 18, the automatic and manual changeover switch 20;
The steer lock release switch 21 is located in the cab of the truck, for example, on the instrument panel, and the steer lock release switch 21 is connected to the automatic and manual changeover switch 20 and the lock valve 14. The manual steer lock circuit 18 is provided between the solenoid coil and the solenoid coil.

Further, a back up switch 22 in the automatic steering lock circuit 19 is provided in the transmission of the truck and is configured to be energized when the change lever is shifted to the reverse side and selected. . Of course, the back
When the up switch 22 is energized, the back up switch 22, which is located at the rear of the truck's body,
Buzzer 23 operates and back up lamp 2
4 lights up.

Furthermore, the manual and automatic steer lock circuits 18, 19 described above have fuses 25, 26 connected to their automatic and manual changeover switches 20, and
They are each provided so as to be connected in series to the back-up switch 22.

Next, we will describe the running of the rear two-axle truck to which the above-mentioned steer lock device 10 is applied.
When the driver desires to automate the steering lock while driving, he first operates the automatic/manual selector switch 20 to the automatic side (see FIG. 2).

In such conditions, when the truck moves forward, because the back up switch 22 is deenergized, no current flows through the solenoid coil of the lock valve 14 and the cylinder at the lock valve 14 - Port 16 is connected to its exhaust port 17.

Therefore, the rear axle as the caster type steer rear axle is placed in a free axle state, preventing significant tire wear and enabling smooth turning.

In addition, when the truck is moving backward, shifting and selecting the change lever of the truck to the reverse side energizes the back up switch 22, operates the back up buzzer 23, and Up Lamp 2
4 lights up.

In this way, when the back up switch 22 is energized, current flows through the solenoid coil of the lock valve 14 since the steer lock release switch 21 is configured as a normally closed type. , the coil is energized.

When the solenoid coil is energized, the pressure port 15 in the lock valve 14
is connected to its cylinder port 16, and compressed air is delivered to its steer lock cylinders 11 and 12, respectively.

Therefore, by operating the change lever to the reverse side, the rear axle as the caster type steer rear axle is automatically placed in a dead axle state, making it possible to move backward in a stable state.

Of course, even when the steering wheel is locked as described above, if the steering lock release switch 21 is deenergized, the steering lock condition is released.

Further, when the driver is driving the truck, if the driver desires manual operation for steering lock, the driver can operate the automatic/manual changeover switch 20 to the manual side to perform steering lock, and further,
When the steer lock release switch 21 is deenergized, the steer lock state is released.

FIG. 3 schematically shows a modification 30 of the steer lock device 10 described above.

The steer lock device 30 is constructed almost similarly to the above-described steer lock device 10, but an electromagnetic relay 31 is provided in the manual and automatic steer lock circuits 18, 19, and the electromagnetic relay 31 controls the steering.・Efforts are being made to ensure lock-in.

Of course, in the steer lock device 30,
Since the components other than the electromagnetic relay 31 are constructed in the same manner as the above-mentioned steer lock device 10, those component parts are given the same reference numerals as the corresponding parts in the steer lock device 10, and the components are The explanation of is omitted.

The electromagnetic relay 31 is of the plunger type, balanced, so as to energize the solenoid coil of the lock valve 14 when the back-up switch 22 is energized, regardless of operation of the automatic and manual transfer switch 20.・The coil of the electromagnetic relay 31 is connected to the back up switch 22 in the automatic steer lock circuit 19, and the pair of contacts of the electromagnetic relay 31 is connected to the back up switch 22 of the automatic steer lock circuit 19. It is connected to the automatic side and manual side contacts of the automatic and manual changeover switch 20 in the lock circuit 18, respectively.

If the electromagnetic relay 31 is provided in this way, the electric circuit for the lock valve 14 and the electric circuit for the reverse warning device are made independent of each other, improving the safety of the circuits and improving steering control.・
The lock can be ensured.

In the operation of the steer lock device 30,
By providing the electromagnetic relay 31, the only difference is the direction in which the current flows, and the operations of the other components are substantially the same as in the case of the above-mentioned example 10, so the explanation of the operations will be omitted.

From the above, it can be seen that the steer lock device of the invention:
a hydraulic steer lock cylinder that places a caster-type steer rear axle in a free axle condition when the vehicle is moved forward and then places the axle in a dead axle condition when the vehicle is reversed;
An electromagnetic lock located in the hydraulic piping connecting the steer lock cylinder to a source of fluid pressure.
Since the steering lock device of the present invention includes a valve and a back up switch electrically connected to the electric circuit of the lock valve, the steering lock device of the present invention is configured to include a back up switch that is electrically connected to the electric circuit of the lock valve. An electrical circuit installed in the vehicle doubles as a means for operating the electromagnetic locking valve so that the caster steer rear axle is automatically locked and unlocked, i.e., when the vehicle is moving forward.
The caster-type steer rear axle is automatically placed in a free axle state, which prevents significant tire wear and enables smooth turns. The type steer rear axle is automatically placed in a dead axle state, allowing stable reversing, which makes the vehicle easier to drive and makes the whole device simple and inexpensive. It can be manufactured and is extremely practical.

[Brief explanation of drawings]

FIG. 1 is a schematic view showing a specific example of a steer lock device used in a vehicle of the present invention applied to a rear two-axle truck, and FIG. 2 is a schematic diagram showing a specific example of the steer lock device shown in FIG. Schematic diagram showing the electrical circuit for the electromagnetic lock valve in
The figure is a schematic diagram showing a modification of the electric circuit shown in FIG. 2. 11, 12...Stair lock cylinder, 1
3...Pneumatic piping, 14...Solenoid lock valve, 22...Back up switch.

Claims (1)

[Claims] 1. A hydraulic steer type steering system that places a caster type steer rear axle in a free axle condition when the vehicle is moved forward, and places the rear axle in a dead axle condition when the vehicle is reversed. A lock cylinder, an electromagnetic lock valve located in the hydraulic piping connecting the steer lock cylinder to a source of fluid pressure, and a back valve electrically connected to the lock valve's electrical circuit. A steering lock device used in vehicles that includes an up switch.