JPH0139605Y2 - - Google Patents

Description

[Detailed explanation of the idea]

Industrial Application Fields This invention roughly corrects the excessive body tail rise or excessive body tail fall that occurs when a motor vehicle such as a truck is empty or loaded, without causing the hunting phenomenon. This invention relates to a vehicle height adjustment device for an automobile that reduces changes in vehicle posture during loading. BACKGROUND ART A vehicle height adjustment mechanism consisting of a hydraulic ram is provided between a wheel support member and a vehicle body member above the wheel support member, and a movable contact that slides up and down in conjunction with the vertical movement of the wheel support member and an upper and lower contact point fixed to the vehicle body member are provided. A vehicle in which oil is supplied to and discharged from the hydraulic ram only when the engine is rotating and the vehicle is stationary in response to a signal from a vehicle height detection switch consisting of two fixed contacts, thereby maintaining the vehicle height at a constant level. A vehicle height adjustment device has already been developed and published in Japanese Patent Publication No. 13327/1983. Problems that the invention aims to solve: The conventional device described above limits the vehicle height adjustment to only when the engine is running and when the vehicle is stopped, and when the vehicle is running, the vehicle height detection switch is separated from the suspension arm. This is an excellent device that can prevent the wear of the operating parts and the accompanying performance deterioration, but on the other hand, the vehicle height detection switch has a structure that operates by moving in a straight line, so the structure has to be complicated. Or, as soon as the movable contact of the vehicle height detection switch leaves either the upper or lower fixed contact, oil supply or discharge stops, which may cause a so-called hunting phenomenon in which the movable contact and fixed contact repeatedly turn on and off. The problem is that there are too many. Means for Solving the Problems The present invention uses two photo couplers as a vehicle height sensor, and a large body that rotates in conjunction with the vertical movement of the wheel support member and blocks the optical path of both of the two photo couplers. Based on the combination with a disc-shaped shutter formed on the circumference of a diameter arc part, a medium diameter arc part that blocks only the optical path of one photo coupler, and a small diameter arc part that does not block the optical path of both photo couplers. A device that emits three types of vehicle height signals: a vehicle height signal, a high vehicle height signal, and a low vehicle height signal is used to detect the upper and lower limit positions of the vertical stroke of the vehicle height adjustment mechanism and output the upper and lower limit signals, respectively. A position sensor is installed to generate a signal, and the three types of signals from the vehicle height sensor and two types of signals from the position sensor are used to adjust the vehicle height by inputting the upper limit signal of the position sensor and the low vehicle height signal of the vehicle height sensor when the vehicle speed is zero. The vehicle height control circuit operates the mechanism to the lower limit position and operates the vehicle height adjustment mechanism to the upper limit position by inputting the lower limit signal of the position sensor and the high vehicle height signal of the vehicle height sensor. be. Effect: By adopting the above configuration, the vehicle height adjustment mechanism always changes from the lower limit position to the upper limit position in response to the up signal or down signal of the vehicle height control circuit based on the signals from the position sensor and the vehicle height sensor. Since it is a two-position vehicle height control (upper and lower) that operates by a certain stroke from the upper limit position to the lower limit position to correct and maintain the vehicle height within or near the reference vehicle height range, hunting does not occur at all. For example, it is possible to roughly correct an excessive change in the body posture of a truck, such as an excessive rise or drop of the body when the truck is empty or loaded, to the extent that there is no practical problem. Embodiments The details of the present invention will be explained below with reference to embodiments shown in the accompanying drawings. FIG. 1 is a structural schematic diagram and an explanatory diagram of the operation of a vehicle height sensor, in which the vehicle height sensor 1 includes a disc-shaped shutter 2, a first photocoupler 3 and a second photocoupler 4 each consisting of a light emitting element and a light receiving element. The disc-shaped shutter 2 is rotatably supported by the vehicle body member 5 at its central axis 2a, and as shown in FIG. Arm 2b of shutter 2
The two wheels are connected to each other via the wheel support member 7, and rotate around the central axis 2a as the wheel support member 7 moves up and down. The first photocoupler 3 and the second photocoupler 4 are provided on the vehicle body member 5 on the radiation line from the central axis 2a of the disc-shaped shutter 2, and the light between the light emitting element and the light receiving element constituting the photocoupler is provided. The passage is configured so that the disc-shaped shutter 2 can block the passage. The disk-shaped shutter 2 is a first photocoupler 3
One side of the large-diameter circular arc portion 2c, which has a radius and a predetermined angle θ large enough to block the optical paths of both the photocoupler 1 and the second photocoupler 4, blocks the optical path of the first photocoupler 1 and blocks the light of the second photocoupler 4. The medium-diameter circular arc portion 2d has a radius that does not block the optical path, and the other side of the large-diameter circular arc portion 2c has a radius that does not block the optical path of both the first photocoupler 3 and the second photocoupler 4. The large-diameter circular arc portion 2c is continuously formed with the small-diameter circular arc portion 2e, and the two large-diameter circular arc portions 2c are
The first photocoupler 3 and the second photocoupler 4 are connected to the wheel support member 7 by a link 8 so as to be positioned on the equal dividing line. Therefore, the first photocoupler 3, the second photocoupler 4, and the disc-shaped shutter at a high vehicle height and a low vehicle height when the large-diameter arcuate portion 2c is deviated upward or downward by more than half of the predetermined angle θ of the large-diameter arc portion 2c from the reference vehicle height. The positional relationship with 2 is as shown in Figure 1 A and C. The table below summarizes the on/off status of the first photo coupler 3 and the second photo coupler 4 for each of the above vehicle heights.

[Table] In FIG. 2, 9 is a coil spring that elastically supports the wheel support member 7.
For example, an electric vehicle height adjustment mechanism 10 as shown in FIG. 3 is interposed between the coil spring 9 and the vehicle body member 5, and has a structure that can variably control the support point of the coil spring 9 on the vehicle body member side up and down. Ru. In FIG. 3, reference numeral 11 denotes an Atsupa spring seat that supports the upper end of the coil spring 9, and the Atsupa spring seat 11 is connected to the lower end of a support column 12 having a male threaded portion 12a at its center.
The male threaded portion 12a of the support column 12 is connected to the female threaded portion 15a of the final stage gear 15 driven by the electric motor 13 and gear reduction mechanism 14 assembled to the vehicle body member 5.
are screwed together. A stopper 12b is provided at the upper end of the column 12, and is configured to restrict the lowering limit position of the column 12 by coming into contact with the upper edge of the column through hole. Reference numeral 16 denotes a cover that covers the support column 12, and a position sensor 17 is provided on the top of the cover to generate a signal at the upper limit position of the support column 12. The electric vehicle height adjustment mechanism 10 is controlled by a control circuit (not shown) to set the column 1 to the upper limit position where the column 12 comes into contact with the position sensor 17.
The structure is such that the second stopper 12b takes only two positions, the lowering limit position where it abuts the upper edge of the column through hole, and is controlled so as not to stop at an intermediate position. In FIG. 2 showing an example of the circuit diagram of the present invention,
18 is a vehicle speed sensor that outputs an ON signal when the vehicle is stopped and the vehicle speed is zero; 19 is a vehicle height sensor that drives an electric vehicle height adjustment mechanism 10 based on a combination of signals from the vehicle height sensor 1, position sensor 17, and vehicle speed sensor 18 to keep the vehicle height constant. It emits a signal to correct only the height. In the above, the output signal of the vehicle speed sensor 18 when stopped is on, the Atsupah spring seat 11 supporting the vehicle body member side of the coil spring 9 is at the upper end, the output signal of the position sensor 17 is on, and the first photocoupler 3 When the vehicle height is low and the output signals of both the photocoupler 4 and the second photocoupler 4 are on, the electric vehicle height adjustment mechanism 10 raises the vehicle height by a certain amount determined by the distance between the upper limit position and the lower limit position of the strut 12. ,
At high vehicle height, when the Atsupah spring seat 11 is at the lower end, the output signal of the position sensor 17 is off, the first photocoupler 3 is off and the second photocoupler 4 is on, the vehicle height is lowered by the above-mentioned fixed width. Furthermore, when the reference vehicle height is set when both the first photo coupler 3 and the second photo coupler 4 are off, the electric vehicle height adjustment mechanism 10 does not operate even if the Atsupa spring seat 11 is located at either the upper end or the lower end. Therefore, the vehicle height remains unchanged. The vehicle height adjustment mechanism 10 is not limited to one using an electric motor as shown in FIG. 3, but may be of any hydraulic type or pneumatic type within the scope of the object of the present invention. Effects of the invention As described above, according to the invention, a vehicle height sensor consisting of a rotatably supported disk-shaped shutter and two photocouplers, and a coil spring that elastically supports a wheel support member are supported on the vehicle body member side. By using a vehicle height adjustment mechanism that can take only two positions, the upper end and the lower end, which are separated by a predetermined width, the vehicle height can be adjusted when the vehicle is stopped. It is possible to correct extreme vehicle postures such as the rear end of the vehicle without causing a hunting phenomenon, and it is also possible to suppress the deterioration of the cushioning function caused by excessively correcting the vehicle posture especially when overloaded, improving ride comfort. It is easy to install and adjust, and allows reliable maintenance of the vehicle height adjustment device.
This can bring about great practical effects.

[Brief explanation of drawings]

Figure 1 is a, b, and c are structural schematic diagrams and operation explanatory diagrams of the vehicle height sensor according to the present invention, Figure 2 is a circuit diagram showing the control system, and Figure 3 is a structural outline of the electric vehicle height adjustment mechanism. It is a diagram. 1...Vehicle height sensor, 2...Disc-shaped shutter, 3
...First photo coupler, 4... Second photo coupler, 5... Vehicle body member, 6... Wheel, 7... Wheel support member, 9... Coil spring, 10... Electric vehicle height adjustment mechanism, 11 ... Atsupa spring seat, 12 ... Support column, 15 ... Final stage gear, 17 ...
...position sensor, 18...vehicle speed sensor, 19...vehicle height control circuit.

Claims (1)

[Scope of utility model registration request] In a vehicle in which a vehicle height adjustment mechanism is provided between a wheel support member that supports a wheel and a vehicle body member above the vehicle height adjustment mechanism, the upper and lower limit positions of the vertical stroke of the vehicle height adjustment mechanism are detected and an upper limit signal and a lower limit signal are generated, respectively. two photocouplers, a first and a second photocoupler, provided with a position sensor that emits a signal and arranged in parallel on the vehicle body member;
The first photocoupler is rotatably attached to the vehicle body member with a certain point on the extension of the line connecting the first and second photocouplers as a rotation center, and rotates in conjunction with vertical displacement with respect to the wheel support member. A large-diameter arc portion that blocks both optical paths of the second photocoupler and the first
A vehicle height sensor is constructed by combining a disk-shaped shutter with a medium-diameter circular arc portion that blocks only the optical path of the photocoupler and a small-diameter circular arc portion that does not block both the first and second optical paths formed on the circumference. and generates a signal to operate the vehicle height adjustment mechanism from the upper limit position to the lower limit position and from the lower limit position to the upper limit position based on the position sensor signal of the vehicle height adjustment mechanism and the signal of the vehicle height sensor under the condition of zero vehicle speed. A vehicle height control device for an automobile, characterized in that it is provided with a vehicle height control circuit that emits a vehicle height control circuit.