JP3480569B2 - Drive axle weight increase device for front two-axle vehicle - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention increases the axle load on the drive shaft of a front two-axle vehicle such as a truck or trailer having a two-axis steering axle at the front and a single drive axle at the rear. It relates to a device for obtaining.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 6, a front wheel axle 2 to which a front wheel 1 is rotatably mounted has a front portion of a front portion of a truck 9.
The rear wheel axle 4 to which the rear wheel 3 is fixed is suspended via a leaf spring 5 and the rear portion of the truck 9 is suspended via a leaf spring (not shown), and further rearward with a predetermined distance from the front wheel axle 2. A front two-axle axle 9 having two front axles configured to suspend a guide wheel axle 7 on which a guide wheel 6 is rotatably mounted is mounted on a center front portion of a track 9 via a second leaf spring 8. Are known. The front wheel axle 2 and the guide wheel axle 7 in this front two-axle 9 are steering axles, and the rear wheel axle 4 is a drive axle. In this front two-axle vehicle 9, the load capacity can be increased to expand the range of road conditions on which the vehicle can travel, and the load corresponding to the load capacity can be distributed to a plurality of axles to extend the life of the power transmission unit and the tires. It can be extended.

[0003]

However, in the above-mentioned conventional front two-axle vehicle, the front two-axle vehicle climbs up a slope, and the front wheels of the truck reach a flat road continuing to the upper end of the slope, and the guide wheels reach the slope. If it is located at the connection between the road and a flat road, that is, at a bend with a relatively small radius of curvature, the front biaxle will have a so-called twisting phenomenon with the guide wheel axle as the fulcrum, and the load on the rear wheel axle will decrease. I was afraid. As a result, when the front two-axle stopped at the above position and restarted, slippage might occur or the vehicle could not travel smoothly. Further, in the above-mentioned conventional front two-axle vehicle, since the front wheels and the guide wheels respectively mounted on the front wheel axle and the guide wheel axle that are not driven are always grounded, no load is loaded on the loading platform, that is, in a so-called empty state. When traveling, when the load on the drive axle decreases and the front two-axle stops and restarts,
There is a problem that causes slipping. Further, unnecessary rolling resistance is generated in the front wheel and the guide wheel attached to the front wheel axle and the guide wheel axle, which deteriorates fuel consumption and promotes wear of the front wheel and the guide wheel to shorten the life of the wheel itself. There are also defects. An object of the present invention is to provide a drive axle load increasing device for a front two-axle vehicle capable of improving traveling performance by increasing the axle load of a rear wheel axle when a jerky slip phenomenon occurs due to a situation of a traveling road surface or in an empty state. To do.

[0004]

The invention according to claim 1 is
As shown in FIG. 1, a rear wheel axle 18 which is a drive axle suspended on a rear portion of a chassis frame 12 and a chassis frame 1
The front wheel axle 16 suspended from the front part of the second wheel via the first leaf spring 22, and the chassis frame 1 near the rear of the front wheel axle 16.
It is an improvement of a front two-axle vehicle having a guide wheel axle 21 suspended from the front part of the second wheel via a second leaf spring 23. The characteristic structure is that the rear end of the first stack leaf spring 22 is pivotally supported at the front end, the front end of the second stack leaf spring 23 is pivotally supported at the rear end, and the middle is pivotally supported by the chassis frame 28.
And a cylinder 29 configured to swing the equalizer beam 28 so that the rear end of the first leaf spring 22 is lowered together with the front wheel axle 16 and the front end of the second leaf spring 23 is raised together with the guide wheel axle 21. Is equipped with.

In the drive axle load increasing device for a front two-axle vehicle according to the first aspect of the present invention, the front two-axle vehicle 10 has a slipping phenomenon that uses the guide wheel axle 21 as a fulcrum, or the load on the rear wheel axle 18 is increased. The cylinder 29 swings the equalizer beam 28 when the vehicle is empty. As a result, the rear end of the first leaf spring 22 is lowered together with the front wheel axle 16, and the front end of the second leaf spring 23 is raised together with the guide wheel axle 21.
The guide wheel axle 21 approaches the chassis frame 12. As a result, the axle weight of the rear axle 18, which is the drive axle, is increased, so that the above-mentioned slipping phenomenon is eliminated, the slip of the rear wheel 17 is eliminated, and the running performance of the front two-axle vehicle 10 is improved.

The invention according to claim 2 is the invention according to claim 1, and further, as shown in FIG. 3, the front two-axle vehicle 10 is a cab-over track provided with a cavitating device 31, and the cavitating device 31. Is a drive shaft load increasing device for a front two-axle vehicle configured to drive the cylinder 29 by the hydraulic pump 33. In the drive axle load increasing device for a front two-axle vehicle according to the second aspect, the hydraulic pump 33 of the cab-till device 31 conventionally provided in the cab-over track.
Since the cylinder 29 of the present invention is driven by utilizing the above, it is not necessary to separately provide a special pump for driving the cylinder 29, and the drive shaft load increasing device of the present invention can be obtained relatively easily and inexpensively. You can

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Next, a first embodiment of the present invention will be described in detail with reference to the drawings. As shown in FIG. 5, the front two-axle vehicle in this embodiment is a cab overtrack 10 having a tiltable cab 11, and the cab 11 is provided at the rear of a chassis frame 12 provided at the front thereof. The loading platform 13 is mounted continuously in the rear of.
The truck 10 has a front wheel axle 16 to which a front wheel 14 is rotatably mounted, a rear wheel axle 18 to which a rear wheel 17 is fixed, and a guide wheel 19 which is provided behind the front wheel axle 16 with a predetermined space therebetween. And a guide wheel axle 21 attached to the. As shown in FIG. 1, the front wheel axle 16 suspends the front portion of the chassis frame 12 via a first overlapping leaf spring 22, and the rear wheel axle 18 suspends the rear portion of the chassis frame 12 via an overlapping leaf spring (not shown). The guide wheel axle 21 suspends the center front portion of the truck 10 via a second leaf spring 23. The front wheel axle 16 and the guide wheel axle 21 are steering axles, and the rear wheel axle 18 is a drive axle.

The first and second leaf springs 22, 23 are arranged side by side below the outer surfaces of a pair of side members 12a extending in the traveling direction of the truck 10 constituting the chassis frame 12 in the front and rear direction of the traveling direction of the truck 10. The front end of the first leaf spring 22 is pivotally attached to the first spring bracket 24 fixed to the side member 12a, and the second leaf spring 2 is attached.
The rear end of 3 is pivotally attached to the second spring bracket 26 fixed to the side member 12a. Side member 12a between the first leaf spring 22 and the second leaf spring 23
A third spring bracket 27 is fixed to the third spring bracket 27, and the equalizer beam 28 is attached to the third spring bracket 27.
The middle of is pivoted. The rear end of the first leaf spring 22 is pivotally supported by the front end of the equalizer beam 28, and the second leaf spring 2
The front end of 3 is pivotally supported at the rear end of the equalizer beam 28.

Also, the front wheel axle 16 and the side member 12a.
A shock absorber and a stabilizer (not shown) are provided between the first and second leaf springs 22, the shock absorber and the stabilizer, and vibrations received by the front wheel axle 16 from the road surface via the front wheel 14 are attenuated and transmitted to the chassis frame 12. There is no such thing. Further, a shock absorber and a stabilizer (not shown) are provided between the guide wheel axle 21 and the side member 12a, and the guide wheel axle 21 is moved from the road surface via the guide wheel 19 by the second leaf spring 23, the shock absorber and the stabilizer. The received vibrations and the like are attenuated and are not transmitted to the chassis frame 12.

A hydraulic cylinder 29 is provided between the equalizer beam 28 pivotally supported by the third spring bracket 27 and the side member 12a. In this embodiment, the base end of the hydraulic cylinder 29 is pivotally supported by the side member 12a, and the tip of the rod 29a protruding by hydraulic pressure is the third.
It is pivotally supported by an equalizer beam 28 in front of the spring bracket 27. When the hydraulic cylinder 29 causes the rod 29a to project and swings the equalizer beam 28 as shown in FIG. 2, the rear end of the first overlapping leaf spring 22 descends together with the front wheel axle 16 and the second overlapping leaf spring 23. Is configured so as to rise together with the guide wheel axle 21.

As shown in FIG. 3, the cab overtrack 10 is provided with a cab tilting device 31 for tilting the cab 22. This cabling device 31
Is equipped with a cavitating cylinder 32 for actually tilting the cab, and a hydraulic pump 33 for driving the cavitating cylinder 32. The hydraulic pump 33 in this embodiment is composed of an electric pump 33a and a manual pump 33b, and is configured to be able to supply the oil stored in the oil tank 34 to the cabling cylinder 32. A manual tilt valve 36 is provided in an oil passage between the hydraulic pump 33 and the cavitating cylinder 32. The tilt valve 36 is a 4-port, 2-position switching valve, the inlet port 36a is connected to the hydraulic pump 33, the supply port 36b is connected to the cavitated cylinder 32, and the reflux flow path from the cavitated cylinder 32 to the reflux port 36c. Connected. The outlet port 36d is connected to the oil tank 34. The valve 36 is fixed to the chassis frame 16, and the lever 36e
The inlet port 36a and the supply port port 36b communicate with each other and the return port 36c and the outlet port 36d communicate with each other to drive the cavitating cylinder 32 to tilt the cab 11 (FIG. 5). .

The hydraulic pump 33 of the cavitating device 31 is also configured to drive a hydraulic cylinder 29 that swings the equalizer beam 28. Specifically, the drive device 41 of the hydraulic cylinder 29 includes a shutoff valve 42 provided in an oil flow path between the tilt valve 36 and the cavitating cylinder 32, and first and second operation valves 43, 4.
4 and a controller 46 for driving these valves 42, 43, 44. Shutoff valve 42 is 4 port 2
It is a valve for position switching, and the tilt valve 36 and the cavitated cylinder 32 are controlled by a signal from the controller 46.
Is configured to shut off the oil flow path between and. First
The operation valve 43 is a 4-port 2-position switching valve, the inlet port 43a is connected to the hydraulic pump 33, the supply port 43b and the return port 43c are connected to the second operation valve 44, respectively, and the outlet port 43d is an oil tank. 34. This first operation valve 43
Is configured to shut off or establish communication between the cavitating device 31 and the second operation valve 44 in response to a signal from the controller 46.

The second operation valve 44 is a 3-port / 2-position switching valve, and has an inlet port 44a and an outlet port 4a.
4c are connected to the first operation valve 43, and the supply port 44b is connected to the hydraulic cylinder 29. This second
The operation valve 44 supplies the oil supplied by the hydraulic pump 33 connected by the first operation valve 43 to the hydraulic cylinder 29 by a signal from the controller 46, or supplies the oil supplied to the hydraulic cylinder 29 to the oil tank 3
4 to reflux. The rod 29a of the hydraulic cylinder 29 is projected to the driver's seat inside the cab 11,
A driving force increasing switch 47 for swinging the equalizer beam 28 is provided, and the switch 47 is a controller 46.
Connected to the control input of. The control output of the controller 46 is the shutoff valve 42 and the first and second operation valves 43, 4
4 are connected respectively.

When the switch 47 is opened and the switch 47 is closed as shown in FIG. 4 from the state shown in FIG. 3, the controller 46 turns on the shutoff valve 42 to shut off the oil flow path between the shutoff valve 42 and the cylinder cylinder 32. , First
When the operation valve 43 is turned on, the cavitating device 31 and the second
The operation valve 44 is communicated. And the second operation valve 4
4 is turned on to connect the oil by the first operation valve 43 and supply the oil supplied by the hydraulic pump 33 to the hydraulic cylinder 29.
And the rod 29a of the hydraulic cylinder 29 is projected. Here, reference numeral 48 in the drawing is an accumulator for not disturbing the swing of the equalizer beam 28 due to unevenness of the road surface, and reference numeral 49 is a relief valve for returning oil to the oil tank 34 when a pressure of a predetermined value or more is applied. is there.

The operation of the drive shaft load increasing device for a front two-axle vehicle configured as described above will be described. The truck 10 climbs a hill, the front wheels 14 of the truck 10 reach a flat road connecting to the upper end of the hill, and the guide wheels 19 connect the hill to the flat road.
That is, when it is located at a bent portion having a comparatively small radius of curvature, a so-called jerky slip phenomenon occurs with the guide wheel axle 21 as a fulcrum in the truck 10, and the load on the rear wheel axle 18 is reduced. Alternatively, the load on the rear wheel axle 18 decreases in an empty state after the load loaded on the loading platform 13 is unloaded. In order to allow the truck 10 to travel safely and reliably in such a case, the driver closes the switch 47 to cause the rod 29a of the hydraulic cylinder 29 to project as shown in FIG.
Rock 8 As shown in FIG. 2, when the equalizer beam 28 swings, the rear end of the first overlapping leaf spring 22 moves down together with the front wheel axle 16 and the front end of the second overlapping leaf spring 23 moves up together with the guide wheel axle 21. When the guide wheel axle 21 rises and approaches the chassis frame 12, the load on the guide wheel axle 21 decreases, and instead, the load on the front wheel axle 16 and the rear wheel axle 18 increases. As a result, the jerky slip phenomenon is eliminated, and the axle weight of the rear wheel axle 18, which is the drive axle, increases, so that the running performance of the truck 10 is improved without slipping.

[0016]

As described above, according to the present invention, the rear end of the first leaf spring is pivotally supported at the front end thereof, and the front end of the second leaf spring is pivotally supported at the rear end thereof, and the middle portion is supported by the chassis frame. A pivotally supported equalizer beam, and a cylinder configured to swing the equalizer beam so that the rear end of the first leaf spring is lowered together with the front wheel axle and the front end of the second leaf spring is raised together with the guide wheel axle. The equalizer beam is oscillated by the cylinder when the front two-axle vehicle has a loosening phenomenon with the guide wheel axle as a fulcrum or when the load on the rear axle is reduced. As a result, the guide wheel axle moves up and approaches the chassis frame. As a result, the above-mentioned twisting phenomenon is eliminated or prevented, and the axle weight of the rear axle, which is the drive axle, increases, so that the slip of the rear wheels is eliminated and the running performance thereof can be improved.

If the front two-axle vehicle is a cab-over truck equipped with a cavitating device, the cylinder can be driven by using a hydraulic pump of a cavitating device which has been conventionally used. It is not necessary to separately provide a special pump for driving, and the drive shaft load increasing device of the present invention can be obtained relatively easily and inexpensively.

[Brief description of drawings]

FIG. 1 is a diagram showing the configuration of a drive shaft load increasing device for a front two-axle vehicle according to the present invention.

FIG. 2 is a view corresponding to FIG. 1 showing a state in which an equalizer beam of the apparatus is oscillated.

FIG. 3 is a configuration diagram of a drive device for a cylinder including a cavitating device.

FIG. 4 is a configuration diagram corresponding to FIG. 3 showing a state where a rod of a cylinder is projected by the device.

FIG. 5 is a side view of a front twin-axle having the device.

FIG. 6 is a side view of a front twin-axle corresponding to FIG. 5 showing a conventional example.

[Explanation of symbols]

10 front two-axle 12 chassis frame 16 front wheel axle 18 rear wheel axle 21 induction wheel axle 22 1st leaf spring 23 Second leaf spring 28 Equalizer beam 29 cylinders 31 Cabulting device 33 hydraulic pump

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Claims (2)

(57) [Claims] 1. A rear wheel axle (18) which is a drive axle suspended on a rear portion of a chassis frame (12), and the chassis frame (1).
2) A front wheel axle (16) suspended from the front portion of the front wheel axle (22) via a first leaf spring (22) and a second wheel stack on the front portion of the chassis frame (12) near the rear of the front wheel axle (16). In a front two-axle vehicle (10) provided with a guide wheel axle (21) suspended via a spring (23), a rear end of the first leaf spring (22) is pivotally supported at a front end and a rear end is provided. An equalizer beam (28) in which the front end of the second leaf spring (23) is pivotally supported and the middle is pivotally supported by the chassis frame (12).
And the equalizer for lowering the rear end of the first leaf spring (22) together with the front wheel axle (16) and raising the front end of the second leaf spring (23) together with the guide wheel axle (21). A drive shaft load increasing device for a front two-axle vehicle, comprising: a cylinder (29) configured to swing a beam (28). 2. A front two-axle vehicle (10) is a cab overtrack equipped with a cavitating device (31), wherein a hydraulic pump (33) of the cavitating device (31) drives a cylinder (29). The drive shaft load increasing device for a front two-axle vehicle according to claim 1.