JPS5836573Y2 - suspension system - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a suspension system for a vehicle.

For example, in agricultural tractors, the ground clearance of the vehicle body is increased to prevent the bottom surface of the vehicle from coming into contact with field ridges, crops, etc., and therefore the center of gravity of the vehicle body is high. There is no lowering mechanism, and when driving on general roads with working equipment attached to the rear of the tractor, the weight balance is poor and there is even a risk that the tractor may fall backwards.

Similarly, when driving across steep slopes or on uneven terrain, the center of gravity of the vehicle must remain high.
There was a risk that the tractor would roll over, forcing the driver to drive extremely unstable and dangerously, and the vehicle was not normally equipped with a suspension system that could cope with such rough roads, making the ride extremely uncomfortable. was the reality.

In view of the above-mentioned circumstances, and as a result of intensive research, this invention allows the vehicle body's ground clearance to be adjusted easily and quickly. The purpose of the present invention is to provide a suspension system for a vehicle that lowers the ground clearance of the vehicle, lowers the center of gravity, enables stable and safe driving, and provides a comfortable ride.In order to achieve this purpose, Mainly composed of a cylinder, a piston, and a piston rod, and equipped with a shock absorber, a suspension spring, etc., and independently suspending wheels on a vehicle body, the piston rod is fitted onto the outside of the cylinder so as to be slidable relative to the cylinder in the axial direction. A ground clearance adjustment cylinder, which adjusts the ground clearance of the vehicle body by sliding, is provided in a fixed state, and a hydraulic oil supply means with a switching valve is provided for supplying hydraulic oil to the ground clearance adjustment cylinder. A supply position where hydraulic oil is supplied into the height adjustment cylinder, a lock position where relative sliding between the cylinders for ground height adjustment is disabled and the suspension spring and shock absorber are inactive, and a cylinder for ground height adjustment. and an unlocked position in which the suspension spring and the shock absorber are operated by allowing relative sliding between the cylinder and the cylinder.

Hereinafter, a first embodiment in which the present invention is applied to an all-wheel drive agricultural tractor will be explained based on the drawings of FIGS. 1 to 3.
1 is a tractor body, 2 is a transmission case forming a part of the vehicle body 1, and 3 is a cabin added to the vehicle body.

4 is a pair of left and right front wheels.

Reference numeral 5 denotes a pair of left and right front wheel hub axles, which are attached to each front wheel 4 via a disc 6.

A pair of left and right gear cases 7 rotatably support each front wheel hub shaft 5.

A pair of left and right hydraulic motors 8 are attached to the inner side of each gear case 7 and drive each front wheel 4 via a transmission mechanism inside the gear case 7 and the front wheel hub shaft 5.

Note that an upper bracket 9 is provided at the upper end of each gear case 7.
Further, a lower bracket 10 is pivotally connected to the lower end of each case 7 so as to be rotatable about a vertical axis.

Reference numeral 11 denotes a pair of left and right parallel link mechanisms, each mechanism 11 consisting of a pair of upper and lower arms 12 and 13;
The proximal end of 3 is pivotally connected to mounting parts 14 etc. protruding from each side of the mission case 2 so as to be rotatable around a horizontal axis.
The tips of each arm 12° 130 are pivotally connected to the corresponding upper and lower brackets 9° 10 so as to be freely rotatable around a horizontal axis, and each front wheel 4 is attached to the vehicle body 1 so as to be freely movable in parallel in the height direction. , the camber angle of each front wheel 4 is kept constant.

15 is a shock absorber for a pair of left and right front wheels 4. Each absorber 15 is mainly composed of a cylinder 16, a piston 17, and a piston rod 18, and the lower end of each cylinder 16 is pivotally connected to the middle part of each lower arm 13 in the lateral direction. A saucer-shaped suspension unsprung support 19 is fitted in the middle part in the height direction, and a piston 17 is tightly fitted inside the support so as to be relatively slidable in the axial direction, and the piston rod 18 extends upward in the axial direction and is connected to the rod hole 20 of the cylinder 16.
The cylinder 16 is tightly fitted so as to be slidable relative to the cylinder 16 in the axial direction, and the cylinder 16 is sealed with hydraulic oil.

In addition, each piston 17 has an orifice 21 for damping vibration during extension.
A compression damping orifice 22 is provided, and each orifice 21 and 22 is provided with a valve 23 that can be opened and closed.

Reference numeral 24 denotes a ground height adjustment cylinder of the vehicle body 1, which is tightly fitted into the upper end side of the cylinder 16 of each absorber 15 so as to be relatively slidable in the axial direction, and the piston rod 18 is inserted into the rod hole 25 at the upper end. is tightly fitted.

Reference numeral 26 denotes a suspension sprung support, which is fitted into the rond 18 and fixed to the upper end surface of the adjustment cylinder 24.

Reference numeral 27 denotes a pair of left and right coil-shaped suspension springs, which are fitted into the cylinders 16 of each absorber 15 and each adjustment cylinder 24, and are interposed between springs 26 and 19 that move up and down.

39 is a hydraulic device exemplified as a means for supplying hydraulic oil to the inside of each adjustment cylinder 24, and is composed of a hydraulic pump 40, a 4-point 3-position switching valve 41, a hydraulic hose 28, an operating lever 42 for the valve 41, etc. The hydraulic hose 28 is connected to each adjustment cylinder 24.

The hydraulic pump 40 is driven by an engine or the like and discharges oil contained in the tension case 2 as hydraulic oil.

The switching valve 41 has a supply position where hydraulic oil is supplied into the ground height adjustment cylinder 24 by operating the operating lever 42;
Suspension spring 27 and shock absorber 15 disable relative sliding between ground height adjustment cylinder 24 and cylinder 16.
The switching valve can be freely switched between a locked position in which it is inactive, and an unlocked position in which relative sliding between the ground height adjustment cylinder 24 and the cylinder 16 is allowed and the suspension spring 27 and shock absorber 15 are activated. 41, the hydraulic oil is supplied to each adjustment cylinder 24, and the cylinder 24 is
The flow of hydraulic oil is switched between three types, such as placing the cylinder 24 in a locked position with respect to the cylinder 16 of each absorber 15, or placing the cylinder 24 in an unlock position with respect to the cylinder 16 of each absorber 15.

It is obvious that when the switching valve 41 is switched to the unlock position and the ground height adjustment cylinder 24 and the cylinder 16 slide relative to each other so as to separate from each other, illustration is omitted. Cylinder 24 for adjusting ground height from the oil passage
Hydraulic oil is replenished inside.

Reference numeral 29 denotes a pair of left and right mounting brackets, the bases of which are fixed to the mounting portion 14 of the transmission case 2, etc., and extend outward, and a rod hole 30 shaped like a bow is opened at the tip end thereof, and the piston rod 18 is inserted.

26a is a stay of each sprung support 26, and each adjustment cylinder 24 is fixed to each mounting bracket 29 via this stay 26a.

Reference numerals 31 and 32 denote upper and lower buffer pieces made of a rubber material, etc., which are each fitted to the rod 18. The lower buffer piece 32 is interposed between the sprung support 26 and the mounting bracket 29, and the upper buffer piece 31
is provided on the mounting bracket 29.

A retainer 33 is fitted onto each rod 18 and provided on the upper buffer piece 31.

Reference numeral 34 denotes a double nut, which is screwed into a threaded portion formed on the upper end of each rod 18, so that each rod 18 and piston 17 are fixedly attached to each mounting bracket 29.

Note that 35 is a seal member, and each seal member 35 prevents hydraulic oil from leaking from the rod hole 20° 25 of each cylinder 16, 24 and the sliding portion of both cylinders 16, 240.

Further, although not shown, a pair of left and right rear wheels are also attached to the vehicle body 1 by a similar mechanism, and the hydraulic hose 28 is communicated with each adjusting cylinder thereof, supplying hydraulic oil to each front wheel 4 and each rear wheel. Although these steps can be performed simultaneously, they may be performed separately.

FIG. 4 shows a second embodiment in which the present invention is applied to a MacPherson type suspension system, in which the cylinders 16 of each absorber 15
The lower end of the front axle holder 36 is attached to each front axle holder 36, and each front axle holder 36 is connected to a control arm 37 pivotally connected to the side of the transmission case 2 via a ball joint.

38 is a pair of left and right front axles, which are provided on each pedestal 36;
Each front wheel 4 is rotatably supported.

Furthermore, although the pair of left and right rear wheels are attached to the vehicle body 1 by a similar mechanism, they may also be attached as in the first embodiment.

The embodiment is constructed as described above, and when the tractor is used for towing in the field, the switching valve 41 is operated by the operating lever in order to correspond to the working conditions such as the field ridges and the height of the crops. 42 and supplying hydraulic oil into each adjusting cylinder 24, each adjusting cylinder 24 is connected to each absorber 1.
5's cylinder 16 and rise together with each piston 17 and each rod 18, and the vehicle body 1 also rises accordingly,
When the vehicle body 1 rises to a desired height, the switching valve 41 is operated to lock each adjustment cylinder 24 with respect to the cylinder 16 of each absorber 15, and both cylinders 16, 2
4 is in a fixed state as shown in FIG. 2, the vehicle body 1 is fixed in the height direction, and the ground clearance H1 of the vehicle body 1 is secured as shown in FIG. 1 or FIG. Work can be done in the same way as before.

In addition, when lowering the ground clearance of the vehicle body 1 from the above state, operate the switching valve 41, set each adjustment cylinder 24 to the unlock position with respect to the cylinder 16 of the absorber 15, and lock both cylinders 16, 24. When the vehicle body 1 is in a slidable state, the hydraulic oil in each adjustment cylinder 24 is discharged by its own weight, and each piston 17 and each rod are moved while each adjustment cylinder 24 is slid onto the cylinder 16 of the absorber 15. When the vehicle body 1 is lowered to the desired position, the switching valve 41 is operated to fix each adjustment cylinder 24 to the cylinder 16 of each absorber 15. In this state, the vehicle body 1 is fixed in the height direction and work can be performed in the same manner as before.

Next, when driving on general roads, crossing steep slopes, or driving on rough terrain with the tractor attached to the rear, the switching valves 41 are operated to switch the adjustment cylinders 24 to each other. The cylinder 16 of the absorber 15 is placed in the unlock position, and the vehicle body 1 and each adjustment cylinder 24 are lowered in the same manner as above, and each adjustment cylinder 24 is elastically connected to the cylinder 16 of each absorber 15 by each suspension spring 27. If supported, the ground clearance of the vehicle body 1 will be set to H2 as shown in FIG. 1 or FIG. 4, and the center of gravity of the vehicle body 10 will be lowered, preventing the tractor from overturning backwards or rolling over. The fear is reduced and the tractor can run stably and safely.

In this case, especially when driving on rough terrain, each front wheel 4
Each rear wheel is independently suspended, and the impact received by each wheel due to irregularities on the uneven ground is alleviated by each suspension spring 27 and transmitted to the vehicle body 1, and the vibration of each spring 1 is transmitted to each piston. 17 is cylinder 1 of each shock absorber 15
While relatively sliding within the vibration damping orifice 21.6, the vibration damping orifice 21. Or, the valve 23 of the vibration damping orifice 22 during compression is automatically opened by the pressure of the hydraulic oil.
When the hydraulic oil passes through one of the orifices 21 and 220, each spring 270 performs a vibration damping action, resulting in a good riding comfort.

Further, the present invention is applicable to various vehicles other than the above-mentioned tractor, and in the embodiment, the cylinder 16 of each shock absorber 15 is attached to each lower arm 13 or each front vehicle bearing pedestal 36. However, on the contrary, this cylinder 1
6 to the mounting bracket 29, and the piston rod 1
7 and the adjusting cylinder 24 may be attached to each lower arm 13 or each front wheel bearing stand 36, and in the embodiment, the suspension spring 27 is fitted to both cylinders 16°24. It may be equipped separately, and furthermore,
The present invention is also applicable to a suspension system in which something other than a coil spring is used as the suspension spring 27.

Further, in the embodiment, each adjustment cylinder 24 was fixed to each mounting bracket 29 via the sprung support 26 and the stay 26a, but the stay 26a was not used and each adjustment cylinder 24 was fixed to each piston rod 18, Alternatively, it may be detachably fixed to each mounting bracket 29.

The present invention is as described above, and by operating a switching valve, the cylinder for adjusting the ground height is slid relative to the cylinder to adjust the ground clearance of the vehicle body to a desired height in accordance with various driving conditions and work conditions. By setting the switching valve to the lock position after adjusting to By raising the ground clearance of the vehicle and setting the switching valve to the locked position, when working in the field, the vehicle body will move up and down due to the action of the suspension springs and shock absorbers, which will prevent the bottom of the vehicle from coming into contact with the field ridges or crops. You can definitely prevent this fear.

Additionally, when driving on general roads, across steep slopes, or on uneven terrain, the switching valve can be set to the unlocked position to lower the ground clearance of the vehicle and activate the suspension springs and shock absorbers. This allows for stable and safe driving, as well as good riding comfort.

As mentioned above, in this invention, by switching operation of the switching valve,
Selectively switch between a position in which the suspension springs and shock absorbers are kept inactive and the ground clearance of the vehicle body remains unchanged at a desired height, and a position in which the suspension springs and shock absorbers are operated while the vehicle body has a low ground clearance. be able to.

In addition, in this invention, the cylinder for adjusting the ground height is fitted onto the cylinder of the shock absorber so that the cylinder also serves as the piston for adjusting the ground height, which has the advantage that the entire device can be made compact. has.

[Brief explanation of drawings]

Fig. 1 is a front view of the first embodiment of the present invention, also showing the operating state, Figs. 2 and 3 are enlarged sectional views of the main parts of Fig. 1, also showing the hydraulic system, and Fig. 4 is the operating state. FIG. 7 is a partially omitted front view of the second embodiment of the present invention, also showing its state. 1...Tractor body, 4...Front wheel, 7
... Gear case, 9 ... Upper bracket, 10 ... Lower bracket, 11 ... Parallel link mechanism, 12 ... Upper arm, 13 ...
... Lower arm 15 ... Shock absorber 16 ... Absorber cylinder, 17 ...
... Piston, 18 ... Piston rod, 24
...Ground height adjustment cylinder, 27...
Suspension spring, 29...Mounting bracket, 36...
...Front vehicle bearing stand, 37...Control arm, 39...Hydraulic system, 41...Switching valve, 42...Operation lever.

Claims (1)

[Scope of utility model registration request] A shock absorber 15 mainly composed of a cylinder 16, a piston 17, and a piston rod 18, a suspension spring 27, etc. are provided, and the wheels 4 are independently suspended on the vehicle body 1. A switching valve 41 is provided with a ground height adjustment cylinder 24 in a fixed state, which is fitted on the outside of the ground height adjustment cylinder 24 so as to be relatively slidable therein, and by which the ground height of the vehicle body 1 is adjusted by sliding, and supplies hydraulic oil to the ground height adjustment cylinder 24. A hydraulic oil supply means 39 with a switching valve 41 is provided.
A supply position for supplying hydraulic oil into the ground height adjustment cylinder 24, and a lock that disables relative sliding between the ground height adjustment cylinder 24 and the cylinder 16 and deactivates the suspension spring 27 and the shock absorber 15. The suspension system is characterized in that it can be freely switched between the position and the unlocked position in which the suspension spring 27 and the shock absorber 15 are actuated by allowing relative sliding between the ground height adjusting cylinder 24 and the cylinder 16.