JP2980799B2 - Rear suspension used for rear two-axle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rear suspension used for a rear two-axle vehicle, and more particularly to a rear suspension combined with a rocker beam.

[0002]

2. Description of the Related Art A rear suspension combined with a rocker beam used in a rear two-axle vehicle of this type is designed in such a manner that a load is distributed at a predetermined ratio between a front axle after driving and a rear axle after being driven. Is common. And, in that case, when the axle weight of the post-drive front axle is larger than that of the post-drive rear axle, the load capacity is distributed to the post-drive front axle and the post-drive rear axle, and In general, it is possible to secure a driving force during light loading. However, in the case of a rear suspension combined with a rocker beam designed in such a manner, when the total weight of the vehicle is increased, the axle load is excessively applied to the front axle after driving when the vehicle is heavily loaded.

[0003] When the rear suspension with rocker beam is designed in such a manner that the loaded amount is evenly applied to the front axle after the driving and the rear axle after the driven, the front axle after the driving when the heavy loading is performed. On the other hand, on a bumpy road or sloping road, the shared load distributed to the front axle will not be sufficiently applied after driving, and the driving wheels will slip and start. Gets worse. Further, even on a slippery road surface, the drive wheels cause slip and idle. Further, even when the vehicle is empty or lightly loaded, the axle weight of the front axle is reduced after the driving, and the required driving force cannot be secured to the driving wheels, which also causes a problem in the startability. In particular, when the vehicle is vacant or lightly loaded, the startability is further deteriorated when the vehicle retreats. Further, if an auxiliary brake, for example, an exhaust brake or a retarder is applied when traveling in such a loaded state, judder is likely to occur.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to avoid overloading of axles of a rear two-axle axle so that a shared load can be distributed to each axle within an allowable load range, and that a driving force is applied to a drive axle. Secure, secure start when empty or lightly loaded, ensure safe driving, improve startability on bumpy roads, slopes, snowy roads, etc., and drive with empty or lightly loaded The purpose of the present invention is to provide a rear suspension used for rear two-axle vehicles, which avoids judder when the auxiliary brake is applied.

[0005]

Means corresponding to the object and the operation thereof
A trunnion shaft supported by the frame, a pair of rocker beams swingably supported by the trunnion shaft and supporting the rear axle after being driven between the rear ends, and arranged in front of the trunnion shaft; A front end supported on the frame, a rear end correspondingly connected to a front end of the pair of rocker beams via a shackle, and a pair of leaf springs supporting the front axle after driving on the frame; Air bag means supported by the frame to apply a predetermined load to the front axle in a downward direction after driving, a pressure damper communicated with the air bag means, and a regulator for generating the predetermined load in the air bag means. Pressure means,
The pressure regulating means regulates and supplies compressed air from the air pressure source to the air bag means in response to the operations of the transmission shift position switch and the auxiliary brake switch, and The compressed air is discharged into the atmosphere, and the pressure in the air bag means is maintained at a predetermined value to increase the axle load on the front axle after the driving, and the driving force is secured on the front axle after the driving. is there.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a specific embodiment of a rear suspension used in a rear two-axle vehicle of the present invention will be described.
This will be described with reference to the drawings. FIGS. 1 and 2 show a specific example of a rear suspension used in a rear twin axle of the present invention, which is applied to a heavy truck 50 that uses a front rear axle 53 and a rear rear axle 54 as a rear two axle. Example 10 is shown. This rear suspension 10 is configured to be used with a rocker beam, and a trunnion shaft 11 supported and supported between left and right side rails 52 on a frame 51 of the truck 50. A pair of rocker beams 12, 12 slidably supported by the trunnion shaft 11 and supporting the driven rear axle 54 between rear ends thereof; and a pair of rocker beams 12, 12 disposed in front of the trunnion shaft 11, Are the left and right sides of the frame 51
The rear ends of the pair of rocker beams 12, 12 are supported by rails 52, 52 and are connected to the front ends of the pair of rocker beams 12, 12 via shackles 14, 14, respectively.
A pair of leaf springs 13 supporting the frame 51 on the frame 51, and a pair of shock absorbers 15 disposed between the left and right side frails 52 of the frame 51 and the front axle 53 after driving. A pair of shock absorbers 16, 16 disposed between the left and right side rails 52, 52 of the frame 51 and the rear axle 54 after the drive, and a predetermined load supported by the frame 51 and driving the front axle 53 after the drive. Air bag means 17 for applying pressure to the air bag, a pressure damper 18 connected to the air bag means 17, and a pneumatic pressure source 19 in response to operations of a transmission shift position switch 47 and an auxiliary brake switch 48. The air bag means 17
The compressed air is regulated and supplied to the
Compressed air is discharged from the air bag 7 into the atmosphere, and the pressure in the air bag means 17 is maintained at a predetermined value to maintain the pressure inside the air bag means 17.
And pressure regulating means 20 for generating a predetermined load.

Of course, in the large truck 50 to which the rocker-beam combined rear suspension 10 is applied, two driving wheels (not shown) are normally supported on both ends of the front axle 53 after driving. In addition, two driven wheels (not shown) are normally supported at both ends of the rear axle 54 after the driven. After the drive, the front axle 53
Also, it is normally connected to a differential (not shown) incorporated in the differential carrier 55.

The trunnion shaft 11 is supported and supported between a pair of trunnion brackets 27, 27 which are arranged and screwed corresponding to the left and right side rails 52, 52 of the frame 51, and The rocker beams 12, 12 are supported at both ends so as to swing vertically.

The pair of rocker beams 12, 12 are:
After the driven rear axle 54 is passed between its rear ends, the driven rear axle 54 is lifted up and down and supported so as to be able to be lowered, while its front end is connected to the lower end of the shackle 14, 14 via a pin 28, 28. Are connected correspondingly.

The pair of leaf springs 13, 13
Is formed with eyeballs 29, 29 at its front end,
9 and 29 are connected to the rear front spring brackets 31 and 31 of the left and right side rails 52 and 52 of the frame 51 via pins 32 and 32. The eyeball 30, 30 is formed and connected to the upper end of the shackle 14, 14 via a pin 33, 33, and the center portion has a U.
After driving, the front axle 53 is supported on the frame 51 by bolting.

The air bag means 17 uses an air spring, and the air spring 17 has a diaphragm type having a bottom anchor plate 34 at its lower end and a top anchor plate 35 at its upper end. And is fixedly disposed between the lower bracket 36 and the upper bracket 37, and applies a predetermined load, that is, a predetermined force, to the front axle 53 in a pushing direction after driving. Of course, the lower bracket 36 is screwed to the top surface of the differential carrier 55, while the upper bracket 37 is formed in a cross beam and is adjacent behind the front axle 53 after its driving. By the way, the frame 5
1 is fixedly passed between the left and right side rails 52, 52, so that the air spring 17 is
Anchor plate 34 is attached to its lower bracket 36,
The top anchor plates 35 are respectively screwed to the upper brackets 37, and apply the generated predetermined load to the front axle 53 in the pushing direction after the driving.

The pressure damper 18 uses a surge tank, which is adjacent to the upper bracket 37 and the frame 51.
Are fixedly supported by one of the left and right side rails 52, 52, and are connected to the air spring 17 by a communication pipe 40.

The pressure adjusting means 20 includes an air pressure supply pipe 3 connecting the air spring 17 to the air pressure source 19.
9, a pressure regulating valve 21 which is set to a supply pressure, a normally closed solenoid valve 22 which is arranged downstream of the pressure regulating valve 21 in the air pressure supply pipe 39, and is arranged in parallel with the solenoid valve 22. A pressure regulating valve 23 connected to the air pressure supply pipe 39 downstream of the pressure regulating valve 21 and set to an exhaust pressure;
A relief valve 24 connected to the air spring 17 at an air pressure discharge pipe 41 and set to an exhaust pressure, a normally open solenoid valve 25 disposed on the air pressure discharge pipe 41 upstream of the relief valve 24, The relief valve 26 is connected to the air spring 17 and is set to be higher than the supply pressure, and is connected to the electromagnetic coils 44 and 45 in the electric circuit 46 of the normally closed and normally opened solenoid valves 22 and 25. The transmission shift position switch 47 and the electromagnetic coil 4 in parallel with the transmission shift position switch 47 in the electric circuit 46 of the normally closed and normally opened solenoid valves 22 and 25.
4, its auxiliary brake switch 48 connected to
It is composed of

A pressure regulating valve 21 set to the supply pressure is arranged in the middle of the air pressure supply pipe 39 connecting the air spring 17 to the air pressure source 19, and keeps the compressed air of the air pressure source 19 constant. The pressure is reduced and supplied to the air spring 17, and the pressure in the air spring 17 is maintained at a set value. That is, the pressure regulating valve 21 is capable of generating the predetermined force used as the predetermined load on the air spring 17 by maintaining the pressure in the air spring 17 at a predetermined value. In particular, its supply pressure is then
The axle weight of the front axle 53 can be increased after the drive of the axles 53 and 54 within a range where the axle load of the axles 53 and 54 can be avoided. At this time, it is set at a position where the driving force can be secured to the front axle 53 after the driving. In this case, the air pressure source 19 includes a compressor (not shown) driven by a diesel engine (not shown) mounted on the heavy truck 50, a wet tank (not shown), and a reservoir. -It is constituted normally by the tank 38.

As the normally closed type solenoid valve 22, a normally closed type two-way control solenoid valve is used, and when one of the transmission shift position switch 47 and the auxiliary brake switch 48 is closed, a current is supplied. Flows through the electromagnetic coil 44 to excite it, and is opened to supply compressed air from the reservoir tank 38 to the air spring 17.

A pressure regulating valve 23 set at the exhaust pressure is connected to an air pressure supply pipe 39 at an inlet side and an outlet side of the normally closed two-way control solenoid valve 22 by an auxiliary air pressure supply pipe 42.
And allow the air spring to maintain a minimum pressure. In this case, the pressure regulating valve 23 is set to the exhaust pressure by the air spring 17.
When the compressed air is resupplied to the air spring 17 after being evacuated, the load transmission responsiveness is to be ensured. That is, the pressure regulating valve 23 compensates the air spring 17 for a low pressure.

The relief valve 24 set to the exhaust pressure
In other words, when the truck 50 does not start or the auxiliary brake is operated, the air spring 17 is temporarily released from generating the load, so that the stroke of the rear suspension 10 is reduced. The compressed air is discharged from the air spring 17 into the atmosphere when the pressure in the air spring 17 exceeds an allowable value when the air spring 17 is collapsed or when the pressure regulating function is abnormal.
Of course, the exhaust pressure of the relief valve 24 depends on the load transmission responsiveness and the air spring 17 when the compressed air is supplied.
Is set in advance in consideration of the durability.

The normally open type solenoid valve 25 is a normally open type two-way control solenoid valve, and when one of the transmission shift position switch 47 and the auxiliary brake switch 48 is closed, the current is controlled. Flows into the electromagnetic coil 45 to excite the electromagnetic coil 45, and is closed to stop the compressed air discharged from the air spring 17 into the atmosphere by the relief valve 24.

The relief valve 26, which is set higher than the supply pressure, is connected to the air pressure discharge pipe 41 by an auxiliary air pressure discharge pipe 43 on the upstream side of the normally open solenoid valve 25, and the air spring 17 And surge
It functions to prevent overpressure of the tank 18. That is, the relief valve 26 protects the pneumatic circuit.

The transmission shift position switch 47 detects the start of the truck 50, and is a first speed switch mounted on a transmission (not shown) mounted on the truck 50. , A second speed switch, and a reverse speed switch, while its auxiliary brake switch 48
Is to detect the operation time of the auxiliary brake, and the truck 50 is equipped with an exhaust brake (not shown) as the auxiliary brake.
An exhaust brake switch is used that is used for the exhaust brake. Of course, when a retarder (not shown) is mounted on the heavy truck 50 as the auxiliary brake, the auxiliary brake
As the switch 48, a retarder switch is used.

Next, the operation of the above-described rocker-beam combined rear suspension 10 will be described. When the truck 50 is started with the vehicle empty or lightly loaded, the exhaust brake switch 48 is open but the transmission shift position switch 47 is closed, so that the electromagnetic coils 44 and 4 are closed.
5 is energized and its solenoid valve 22 is opened, and at the same time, its solenoid valve 25 is closed, whereby the compressed air is reduced to a constant pressure by the pressure regulating valve 21 and the compressed air is discharged from the reservoir tank 38 to the air tank. Since it is supplied to the spring 17,
The air spring 17 generates the predetermined load. Then, the load generated in the air spring 17 acts on the front axle 53 after the drive through the lower bracket 36 in the pushing direction. As such, the post-drive front axle 53 is depressed with the predetermined load to increase the shared load, and the driving force is ensured, while the driven rear axle 54 is reduced in the shared load, and Thereafter, the shared load is appropriately distributed to the two shafts 53 and 54 within the range of the allowable load, so that the truck 50 is reliably started regardless of such loading conditions, and
Driving becomes advantageous. That is, then the biaxial 5
Since the axle weight movement is performed between 3, 54, the truck 50 is adapted to running conditions, road conditions, road surface conditions, and the like, and for example, the slip of its driving wheels is suppressed on slippery roads, uneven roads, slopes, and the like. Being able to start reliably.

When the exhaust brake is operated while the truck 50 is running, the transmission shift position switch 47 is opened, but the exhaust brake switch 48 is opened. Since the circuit is closed, the pressure regulating means 20
Is operated in the same manner as in the case of the above-mentioned start, and accordingly, the air spring 17 generates the predetermined load, and pushes the generated load to the front axle 53 after the driving. Acts in the down direction. In this way, the front axle 53 after driving is pushed down by a predetermined load to increase the shared load, and the braking force is ensured, so that the brake is advantageous and the traveling is safe. In addition, judder which occurs when the exhaust brake is applied is avoided, and brake lock which occurs in the driven wheel at that time is also avoided.

Of course, so, then the two axes 53, 54
Since the shared load is appropriately distributed within the range of the allowable load, in the state of heavy load, for example, in the state of constant load, overload of the front axle 53 after drive and the rear axle 54 after driven is avoided, Such an axle load movement is then possible between the two axles 53, 54, so that the axle load of the two axles 53, 54 can then be distributed closer to equalization, so that the gross vehicle weight can be set higher. become.

As will be apparent from the specific embodiments of the present invention described above with reference to the drawings, one skilled in the art to which the present invention pertains will appreciate the subject matter of the present invention. Is the nature of the invention (na
), and are readily embodied in other aspects that are objectively perceived as inherent in them. Of course, the contents of the present invention are indispensable for the establishment of the invention corresponding to the subject of the invention.

[0025]

As can be understood from the above description, the rear suspension used in the rear two-axle vehicle of the present invention has a trunnion shaft supported by a frame, and is swingably supported by the trunnion shaft. A pair of rocker beams that support the rear axle after being driven between the rear ends, and are disposed in front of the trunnion shaft, the front ends are supported by the frame, and the rear ends are shackled to the front ends of the pair of rocker beams. And a pair of leaf springs that support the front axle after driving on the frame, and air that is supported by the frame and applies a predetermined load to the front axle after driving in the downward direction. Operation of the bag means, the pressure damper communicated with the air bag means, the transmission shift position switch and the auxiliary brake switch In response, the compressed air is regulated and supplied from the air pressure source to the air bag means, the compressed air is discharged from the air bag means into the atmosphere, and the pressure in the air bag means is maintained at a predetermined value. The rear suspension used in the rear two-axle vehicle according to the present invention includes a pressure adjusting means for generating the predetermined load in the air bag means. The axle weight of the axle is increased by a predetermined load, and the shared load of the rear two axles can be distributed within the allowable load range.Accordingly, when the vehicle is empty or lightly loaded, the driving force is secured and the start is reliable. In addition, the braking force is ensured, and the braking is advantageous, so that the driving becomes safer, especially on slippery roads, bumpy roads, sloping roads, and the like, and the driving of the driving wheels by the slip. The axle is suppressed, the starting and braking are ensured, and safe driving is ensured.In heavy loading, axle overload is avoided on each axle, and furthermore, running with empty or light loading When the auxiliary brake is applied, the occurrence of judder is avoided,
Furthermore, by increasing the axle load by a predetermined load on the front axle after the drive at the time of starting or light loading, it becomes possible to distribute the axle load of the two axles near equalization thereafter, and accordingly, Therefore, the total weight of the vehicle can be set large, and in addition, when the spring constant of the air bag means is reduced by the pressure damper and compressed air is supplied to and discharged from the air bag means, pressure fluctuation can be reduced. Accordingly, the generation of vibration affecting the suspension is suppressed, and the minimum pressure is secured in the air bag means and the pressure damper by the pressure adjusting means, and the air bag means is crushed by the suspension stroke to release the compressed air into the atmosphere. At the time of discharging, the air bag means is prevented from being excessively crushed, and the air bag means has smooth expansion and contraction and durability,
When supplying compressed air, responsiveness of load transmission is ensured by the pressure regulating means, and as a result, it is very useful and practical for a rear two-axle vehicle.

[Brief description of the drawings]

FIG. 1 is a schematic side view showing a specific example of a rear suspension used in a rear two-axle vehicle of the present invention, which is applied to a large truck using a front rear axle and a rear rear axle as rear two axles. FIG.

FIG. 2 is a pneumatic circuit diagram of the rear suspension shown in FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 11 Trunnion shaft 12 Rocker beam 13 Leaf spring 17 Air bag means / air spring 18 Pressure damper / surge tank 20 Pressure regulating means 21 Pressure regulating valve set to supply pressure 22 Normally closed solenoid valve 23 For exhaust pressure Pressure regulating valve to be set 24 Relief valve to be set to exhaust pressure 25 Normally open solenoid valve 26 Relief valve to be set higher than supply pressure 47 Transmission shift position switch 48 Auxiliary brake switch

Claims (20)

(57) [Claims] 1. A trunnion shaft supported by a frame, a pair of rocker beams swingably supported by the trunnion shaft and supporting a rear axle after being driven between rear ends, and a pair of rocker beams of the trunnion shaft. Placed forward,
A front end supported on the frame, a rear end correspondingly connected to a front end of the pair of rocker beams via a shackle, and a pair of leaf springs supporting the front axle after driving on the frame; Air bag means supported by the frame to apply a predetermined load to the front axle in a downward direction after driving, a pressure damper communicating with the air bag means, a transmission shift position switch and an auxiliary brake switch. In response to the operation, the compressed air is regulated and supplied from the air pressure source to the air bag means, the compressed air is discharged from the air bag means into the atmosphere, and the pressure in the air bag means is set to a predetermined value. And a pressure adjusting means for generating the predetermined load in the air bag means while maintaining the air bag means. 2. The rear suspension used in a rear two-axle vehicle according to claim 1, wherein said air bag means is an air spring. 3. The rear suspension according to claim 1, wherein the pressure damper is a surge tank. 4. The rear suspension used in a rear two-axle vehicle according to claim 1, wherein the transmission shift position switch is a first speed switch, a second speed switch, and a reverse speed switch. 5. The rear suspension according to claim 1, wherein the auxiliary brake switch is an exhaust brake switch. 6. The rear suspension according to claim 1, wherein the auxiliary brake switch is a retarder switch. 7. The rear suspension used in a rear two-axle vehicle according to claim 1, wherein the auxiliary brake switches are an exhaust brake switch and a retarder switch. 8. The transmission shift position switch according to claim 1, wherein the first speed switch, the second speed switch, and the reverse speed switch are provided, and the auxiliary brake switch is an exhaust brake switch. Rear used in the rear two-axle described in 1
suspension. 9. The system of claim 1, wherein the transmission shift position switch is a first speed switch, a second speed switch, and a reverse speed switch, and the auxiliary brake switch is a retarder switch. Rear suspension used for the rear axle described. 10. The transmission shift position switch is a first speed switch, a second speed switch, and a reverse speed switch, and the auxiliary brake switch is an exhaust brake switch and a retarder switch. The rear suspension used for a rear two-axle according to claim 1, wherein 11. A trunnion shaft supported by a frame, and a pair of rockers supported swingably by the trunnion shaft to support a rear axle after being driven between rear ends.
A beam and a forward end of the trunnion shaft, a front end supported by the frame, a rear end correspondingly connected to a front end of the pair of rocker beams via a shackle, and a drive front axle. A pair of leaf springs supported by the frame, air bag means supported by the frame to apply a predetermined load to the front axle after driving in a downward direction, and a pressure damper communicated with the air bag means, Pressure regulating means for maintaining the pressure in the air bag means at a predetermined value and generating a predetermined load on the air bag means, and the pressure regulating means comprises an air pressure means for connecting the air bag means to an air pressure source. A pressure regulating valve arranged on the supply pipe and set to the supply pressure, a normally closed solenoid valve arranged on the air pressure supply pipe downstream of the pressure regulating valve, and the pressure regulating valve arranged in parallel with the solenoid valve of A pressure regulating valve connected to the air pressure supply pipe on the flow side and set to the exhaust pressure, a relief valve connected to the air bag means by the air pressure discharge pipe and set to the exhaust pressure, and upstream of the relief valve Normally open solenoid valve arranged on the air pressure discharge pipe on the side, a relief valve connected to the air bag means and set at a higher pressure than the supply pressure, and electricity of the normally closed and normally opened solenoid valves A transmission shift position switch connected to an electromagnetic coil in a circuit, and an auxiliary connected to the electromagnetic coil in parallel with the transmission shift position switch in an electric circuit of the normally closed type and normally open type solenoid valve. Rear suspension used for rear two-axle vehicles, consisting of a brake switch. 12. The rear vehicle according to claim 11, wherein the air bag means is an air spring.
suspension. 13. The rear vehicle according to claim 11, wherein the pressure damper is a surge tank.
suspension. 14. The rear suspension according to claim 11, wherein the transmission shift position switches are a first speed switch, a second speed switch, and a reverse speed switch. 15. The rear suspension used in a rear two-axle vehicle according to claim 11, wherein the auxiliary brake switch is an exhaust brake switch. 16. The rear suspension according to claim 11, wherein the auxiliary brake switch is a retarder switch. 17. The rear suspension used in a rear two-axle vehicle according to claim 11, wherein the auxiliary brake switches are an exhaust brake switch and a retarder switch. 18. The transmission shift position switch according to claim 18, wherein the first shift switch, the second shift switch, and the reverse shift switch, and the auxiliary brake switch is an exhaust brake switch. 12. A rear suspension used for a rear two-axle vehicle according to item 11. 19. The method of claim 11, wherein the transmission shift position switch is a first speed switch, a second speed switch, and a reverse speed switch, and the auxiliary brake switch is a retarder switch. Rear suspension used for the rear axle described. 20. The transmission shift position switch according to claim 1, wherein said transmission shift position switch is a first speed switch, a second speed switch, and a reverse speed switch, and said auxiliary brake switch is an exhaust brake switch and a retarder switch. The rear suspension used in a rear two-axle vehicle according to claim 11, wherein