JPS61175182A - Steer lock device used for rear two-axle type vehicle - Google Patents

Abstract

PURPOSE:To secure the safe travel of a vehicle by providing a normally-closed air vent port on a pipeline communicated to steer lock cylinders and opening this air vent port at a failure of an electric circuit or a fluid circuit to release the compressed air in the cylinders. CONSTITUTION:When an electric circuit of a solenoid valve 17 and a control unit (not shown in the figure) fails or an air pressure failure occurs in an air pressure source 15, the blind plug 22 of a cross pipe connector 20 is removed to open an air vent port 21. Thereby, the compressed air in the pressure chamber 23 of a pair of steer lock cylinders 13, 14 is discharged into the atmosphere. As a result, steer rear axles 52, 53 are put in a steer lock condition, and rearmost wheels 64, 65 are locked in a direct advance condition.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application/Related Applications The present invention relates to a steer lock device used in a rear two-axle type vehicle in which the rear axle is configured as a steer type.

BACKGROUND ART In recent years, large vehicles, such as large buses, have a three-axle configuration, in other words, two rear axles, to reduce the axle load, and in particular, the last axle is configured as a steer type to speed up low and medium speeds. When driving at high speeds, the steer type last axle is placed in a self-steering state to ensure a minimum turning radius, smooth turns, and improve handling stability. The last steerable axle is put in a steer-locked state, that is, in a straight-ahead state, to improve steering stability, and of course, when suddenly braking or reversing, the last steered axle is put in a steer-locked state. This has improved driving stability.

However, since an electrically controlled pneumatic cylinder is used to bring the steer-type last axle into the self-steering state and the steer-lock state, in the event of an electrical system failure or loss of air pressure, a so-called emergency situation may occur. Safety measures became necessary to ensure safe driving.

OBJECTS AND PROBLEMS OF THE INVENTION An object and problem of the present invention is to maintain the safety of the vehicle by placing the steer type last axle in a steer-locked state, in other words, in a straight-ahead state in the event of an electrical circuit failure or pneumatic pressure failure in the pneumatic circuit. The purpose of the present invention is to provide a steering lock device used in a rear two-axle type vehicle to ensure running.

Summary of the structural invention related to the object and problem: Contents of the claimed invention In relation to the above-mentioned object and problem, the steering lock device used in the rear two-axle type vehicle of the present invention has a steering lock device installed at both ends of the rear axle. a pair of push means connected correspondingly to a pair of rotatably coupled steer rear wheel axles; and a pair of push means arranged corresponding to the push means to push the push means to push the steer rear wheel axles at both ends of the rearmost axle. A pair of spring steer lock air cylinders that lock rotation, pneumatic piping that connects a pneumatic source to the spring steer lock air cylinders, a relay valve disposed on the pneumatic piping, and A solenoid valve is placed in the control piping that connects the control port of the relay valve to its air pressure source side, and on the downstream side of the relay valve,
The pneumatic valve is formed in the pneumatic pipe and includes an air vent that is normally blocked, and the solenoid valve and the electrical circuit due to the solenoid valve break down or the pneumatic circuit of the relay valve still has a pneumatic pressure loss. When this occurs, the air vent is opened, compressed air is extracted from the spring steer lock air cylinder, and the steered rear wheel axle is placed in a steer locked state, that is, in a straight-ahead state.
Of course, during normal driving, the driving speed, sudden braking,
and its spring steer lock upon retraction.
Compressed air is supplied to and discharged from the air cylinder to place the steered rear wheel axle in either a self-steering state or a steer-locked state.

Description of Specific Examples Preferred specific examples of the steering lock device used in a rear two-axle vehicle according to the present invention will be described below with reference to the drawings.

FIGS. 1 and 2 show a specific example 10 of the steering lock device of the present invention applied to a rear twin-axle bus.

The steer and lock device 10 has a front axle (not shown) disposed in front of a chassis frame (not shown), and a pair of front wheel axles (not shown) rotatably connected to both ends of the front axle.
A rear axle (not shown) is located rearward of its chassis frame, and a rear axle (not shown) is positioned rearward of its chassis frame, and a power transmission device (not shown) is steered by a driver steering (not shown) in response to steering inputs. The bus is driven by an engine (not shown) via an engine (not shown), and is further applied to a two-axle bus after the last axle 50 located in its chassis frame immediately after the axle is assembled in a steer type. It is something that
It is attached to the steer type last axle 5o, and places the steer type last axle 50 in either a self-steer state or a steer lock state depending on the traveling speed, and then puts it in the steer lock state in the event of sudden braking or reversing. put,
Further, when the electric circuit fails or a pneumatic pressure failure occurs in the pneumatic circuit, the steer type rear axle 50 is placed in a steer lock state. Of course, the steer type rear axle 50 has a rear rear axle 51 disposed at the rear of the chassis frame immediately after the rear axle, and a pair of steer rear wheel axles 52 degrees rotatably connected to both ends of the rear axle 510. 53, tie rod 56 and Danno'e6
1, and its steer rear wheel shafts 52 and 53 are
It is fixed to the knuckle 54.55, and the knuckle 54゜5
5 are rotatably attached to both ends of the rear axle 51 via king bins. In particular, the knuckles 54.55 are connected to the knuckle control arms 57, 58 and tie rod arms 59.60.
The push means 11, 12 and the tie rods 56 are structured to facilitate connection.

The steer lock device 10 includes a pair of steer rear wheel axles 52.5 rotatably connected to both ends of the rearmost axle 510.
A pair of push means 11.12 connected correspondingly to 3.
and arranged corresponding to the push means 11°12,
Pushing the push means 11°12, the last axle 5
a pair of spring steer lock air cylinders 13.14 locking the rotation of its steer rear wheel axle 52.53 at both ends of the wheel; A connected pneumatic pipe 16, a relay pulp 17 arranged on the pneumatic pipe 16, and an electromagnetic pipe arranged on the control pipe 18 connecting the control port 39 of the relay pulp 17 to the pneumatic source side of the pneumatic pipe 16. Downstream of the valve 19 and its relay pulp 17, its pneumatic line 16
The air vent 21 is formed at the branch point and is normally closed.
, a control unit (not shown) that operates the solenoid valve 19 , and a protection pulp (not shown) placed in the pneumatic pipe 16 upstream of the connection point of the control pipe 18 . It is composed of:

The pushing means 11, 12 are constituted by push sleeves each having a rod guide der (not shown) at one end and a goal joint (not shown) at the other end, - threadedly connected to the joint rannuckle control arm 57, 58 correspondingly connected to its steer rear wheel axle 52, 53, parallel to the axis of its rearmost axle 51, as shown in FIG. It is located.

The spring steer lock air cylinder 13
．． 14 is a pair of brackets (62.6) fixed to the rear axle 51, as can be seen from FIG.
3 and its push sleeve 11.
They are combined in correspondence with 12.

The spring steer lock air cylinder 13
．． 14 also has a structure, as can be understood from FIG. Cylinder 23 rod cover 2
A push rod 30 that can be taken in and out from the cylinder 23 and whose base is connected to the piston 29, and a steer lock spring 31 that is disposed within the cylinder 23 so as to push out the push rod 30. There is.

Of course, the spring steer lock air cylinder 13,14 is provided with a port 26 in the head cover of the cylinder 23, through which compressed air is delivered to the pressure chamber 27 of the cylinder 23, causing the piston to 29 is the spring chamber 28 of the cylinder 23;
The push rod 30 is retracted and the steer lock spring 3 is slid into its cylinder 23 against the steer lock spring 31 located in the
1 is configured to release the steer lock operation.

The pneumatic pipe 16 consists of a tank side pipe 33 and a pair of cylinder side pipes 34 and 35.
4.35 is configured in a branched arrangement structure connected by a cross-guive connector 20 that uses one of the four connection ports as the air vent 21, and the tank side piping 33 is connected to the air of the air pressure source 15.・Connect to the tank 32, and connect the cylinder side piping 34, 35 to the port 26 formed in the cylinder 23 of the spring steer lock air cylinder 13. An air pressure source 15 is connected to the air cylinders 13 and 14.

The air pressure source 15 includes an air tank 32 and its air pressure source 15.
It is connected to the tank 32 by piping (not shown), is driven by an engine in its path, and is configured with a compressor (not shown) that supplies compressed air to the air tank.

The relay pulp 17 is arranged in the tank-side pipe 33 of the pneumatic pipe 16 and supplies compressed air to the air tank 32.
The compressed air supplied to the spring steer lock air cylinder 13.14 is discharged from the spring steer lock air cylinder 13.14 to the atmosphere.

The relay valve 17 includes a feed valve (not shown) disposed within the valve body and an exhaust valve (not shown) driven by a tire flam, and also includes a tank inlet in the valve body.・Port 36,
The structure includes a cylinder port 37, an exhaust port 38 and a control port 39, that is, it is made in the structure of a relay valve used in a vehicle air brake, and its tank port 36 and cylinder port 37
is connected to the tank side piping 33 of the pneumatic piping 16, and the control port 39 is connected to the tank side piping 33 of the pneumatic piping 16 upstream of the connection point of the tank port 36 by the control piping 18. .

The solenoid valve 19 is disposed in the control piping 18, electrically connects the solenoid coil 40 to the control unit, and is driven by the control unit to direct the compressed air in the air tank 32 to the relay.
The valve 17 acts on the tire flam, and the compressed air acting on the tire flam is discharged into the atmosphere.

Still, the control unit is electrically connected to a vehicle speed sensor (not shown), a brake switch (not shown), and a backup lamp switch (not shown); ·switch,
In response to signals from the pack-up lamp switch and the pack-up lamp switch, the current flowing through the solenoid coil is controlled to operate the solenoid valve 19.

Of course, the control unit is comprised of input and output circuits, arithmetic circuits, memory circuits, control circuits, power supply circuits, and the like.

The air vent 21 is connected to its cross pipe connector 20.
Normally, it is closed with a blind plug 22, and its solenoid valve 19, control
If the electrical circuit of the unit malfunctions or if the air pressure source 15
When a loss of air pressure occurs, the compressed air is discharged from the cylinder 23 of the spring steer lock air cylinder 13.14, and the steer lock spring 31 locks the steer rear wheel axle 52.53. put it on.

Next, the operation of the above-mentioned steering lock device 10 will be described according to the running state of the rear two-axle bus.If the bus is currently running at a low speed, the signal from the vehicle speed sensor will cause the The control unit controls the current flowing through the solenoid coil 40 and the solenoid valve 1.
Let 9 open.

When the solenoid valve 19 is opened in this way, the compressed air is
Air flows from the air tank 32 to the relay valve 170 control port 39 and acts on a diaphragm in the relay valve 17 to actuate the exhaust and feed valves, and at the relay valve 17 to control the tank port 36. to cylinder port 37.

As such, in the relay valve 17, the tank ;t? - When the port 36 is connected to its cylinder port 37, compressed air flows from the air tank 32 to the pressure chamber 27 of the cylinder 23 via the pneumatic line 16 and, in FIG. 31, the piston 29 is moved to the right.

As such, when the piston 29 is moved to the right within the cylinder 23, the push rod 30 is retracted into the cylinder 23 with the piston 29, and the tip of the push rod 30 That push three 7'11. .

12 is located within the rod guide bore, away from the bottom wall of the rod guide bore, allowing movement of the push sleeve 11.12, so that the steer rear wheel axle 52.53 is placed in self-steering condition.

Therefore, when the bus turns, the steer rear wheel axles 52, 53 follow the steering operation, and the bus turns smoothly with a small turning radius.

If the bus is running at high speed, the control unit controls the current flowing through the solenoid coil 4o and closes the solenoid valve 19 based on a signal from the vehicle speed sensor.

Thus, when the solenoid valve 19 is closed, the compressed air acting on the diaphragm in the relay pulp 17 is discharged to the atmosphere through the solenoid valve 19, and in the relay pulp 17, cylinder z-
) 37 is connected to the exhaust port 38.

As such, in the relay pulp 17, when the cylinder port 37 and the exhaust port 38 are connected, the compressed air passes through the steer lock cylinder side of the pneumatic piping 16, and from the pressure chamber 27 of the cylinder 23 to the atmosphere. As the compressed air in the pressure chamber 27 is vented, the piston 29 in FIG.
Moved to the left within 3 seconds.

As such, when the piston 29 is moved to the left within the cylinder 23, the push rod 30 follows the piston 29 and moves into the cylinder 23.
The tip of the push rod 30 is formed in the push sleeve 11.12.
Pressing against the bottom wall of the guide via, the movement of its push sleeve 11, 12 is prevented.

As a result, its steer rear wheel axle 52.53 is placed in a steer lock condition, and the rearmost wheel 64.65 is locked in a straight-ahead condition.

Therefore, when the bus turns, the bus turns smoothly, and its running is stabilized, and accordingly, its handling is stabilized.

Furthermore, if the bus is braked suddenly, the switching action of the brake switch will cause the control
The unit controls the current flowing through the solenoid coil 40 and the solenoid valve 19 is closed. As a result, its steer rear wheel axle 52,53 is placed in a steer lock condition, as in the case of high-speed travel, and the rear wheel 64,65 is locked in a straight-ahead condition.

Therefore, at that time, the bus is stably stopped.

Furthermore, if the bus is retracted, the switching action of the backup up lamp switch causes the control unit to control the current flowing through the solenoid coil and the solenoid valve 19 is closed. the result,
The steer rear wheel axles 52 and 53 are placed in a steer lock state, as in the case of high-speed travel, and the rear wheels 64 and 65 are locked in a straight-ahead state.

Therefore, even when the bus turns, the bus turns smoothly.

Furthermore, if the solenoid valve 19 or the electric circuit of the control unit fails, or if the air pressure source 15 suffers a loss of air pressure, the blind plug 22 is removed and the air vent 21 is opened.

Thus, when the air vent 21 is opened, the compressed air is discharged from the pressure chamber 27 of the cylinder 23 into the atmosphere via the cylinder side piping 34.35, so that the steered rear wheel axle 53.53 As with high speed driving,
The vehicle is placed in a steer lock state and the rear wheels 64, 65 are locked in a straight-ahead state.

Therefore, even in such a case, the bus can safely run on its own.

Although the above-described steer lock device 10 was described as being applied to a rear twin-axle bus in which the clutch and transmission were directly operated manually, it is also possible to install a clutch and transmission that are servo-operated by a computer. It can also be easily applied to rear two-axle vehicles.

Further, in the steer lock device 10 described above, the push means 11.12 was described as being connected to the steer rear wheel shaft 52.53, but the push means 11, 12 can also be replaced with the push rod 30. In that case, the push sleeve 11.12 is connected to the piston 29 of its spring steer lock air cylinder 13.14.

Conveniences and Benefits of the Invention From the foregoing, it can be seen that compared to the steer lock devices used in rear twin-axle vehicles that have already been proposed and used, the steerer lock device used in rear twin-axle vehicles of the present invention is better. - In the locking device, a pair of push means are connected correspondingly to a pair of steer rear wheel axles rotatably connected to both ends of the rear axle, and a pair of spring steer lock air cylinders correspond to the push means. the push means locks the rotation of the steer rear axle at both ends of the rear axle, the pneumatic piping connects the pneumatic source to the spring steer lock air cylinder, and the relay valve is disposed in the pneumatic piping, a solenoid valve connects the control port of the relay valve to the pneumatic source side, and an air vent is formed in the pneumatic piping downstream of the relay pulp, normally Therefore, the steer lock device used in the rear two-axle vehicle of the present invention prevents the steer rear wheel axle from entering the self-steer state when the vehicle is running at low or medium speeds. The steer type last axle, that is, the steer rear wheel axle follows the steering operation, ensuring a minimum turning radius when turning, smoothing the turn, and improving handling stability. tire wear is prevented, and when the vehicle is running at high speed, its steer rear wheel axle is placed in a steer lock state, improving running stability and turning stability, and improving steering stability. Furthermore, when the vehicle suddenly brakes or backs up, the steer rear wheel axle is placed in a steer lock state, allowing the vehicle to be safely and smoothly stopped and backed up. In addition, if air pressure loss occurs on the air pressure source side, by opening the air vent port,
Its steer rear wheel axle is placed in a steer lock state, making self-propulsion safe and practical.

As for the relationship between the invention and the specific examples, from the specific examples of the present invention described with reference to the drawings, various design modifications will be apparent to those who have ordinary knowledge in the technical field to which this invention pertains. Modifications and alterations may be easily made, and furthermore, the content of this invention may be substantially the same as that invention in that it satisfies essentially the same problem as that invention and achieves the same effect as this invention. could easily be replaced by an identical aspect.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a steering lock device used in a rear two-axle vehicle according to the present invention applied to a rear two-axle path, and FIG. FIG. 3 is a vertical cross-sectional view of the steer lock cylinder. 11.12...Pair of push means, 13.14...
・Pair of spring steer lock air cylinders, 32...Air tank, 16...Pneumatic piping, 1
7... Relay pulp, 19... Solenoid valve, 21...
・Air vent. , -22-Meshima 112] Figure 2

Claims (1)

[Claims] A pair of push means connected correspondingly to a pair of steer rear wheel axles rotatably connected to both ends of the rear axle; a pair of spring steer lock air cylinders for locking rotation of the steer rear axle at opposite ends of the rearmost axle; pneumatic piping connecting a pneumatic source to the spring steer lock air cylinders; A relay valve placed in the piping, a solenoid valve placed in the control piping that connects the control port of the relay valve to the pneumatic source side, and a solenoid valve formed in the pneumatic piping on the downstream side of the relay valve. , a steer lock device used in rear twin-axle vehicles that includes an air vent that is normally blocked.