JPS631601Y2 - - Google Patents

Description

[Detailed explanation of the idea] This invention relates to a shock absorber device.

As a conventional shock absorber device, the one shown in FIG. 1, for example, is known. (Refer to Japanese Utility Model Application Publication No. 55-114708.) The structure of this shock absorber device is a variable orifice that generates a damping force in a hydraulic shock absorber 4 provided between a vehicle body 2 on which a prime mover 1 is mounted and wheels 3. and a drive device that changes the flow cross-sectional area of the variable orifice. The control circuit 6 includes a control circuit 6 for controlling changes.

However, in such a conventional shock absorber device, the damping force of the shock absorber 4 is changed depending on the speed of the vehicle body 2, so when a transmission mechanism is interposed between the prime mover 1 and the wheels 3, There was a problem in that changes in damping force could not always be controlled optimally. In other words, when increasing the gear ratio and applying large driving force to the vehicle body 2 even at low vehicle speeds, for example when starting, the conventional shock absorber device reduces the damping force to ensure the ground contact force of the drive wheels 3 and optimize the vehicle body 2. It was not possible to obtain sufficient damping force to maintain the vehicle in a normal position. Furthermore, even when the vehicle turns at a low speed, when turning with a large gear ratio, the vehicle body 2 is subjected to a large centrifugal force, so the damping force of the shock absorber must be large to ensure the stability of the vehicle body 2. However, the conventional shock absorber device cannot provide sufficient damping force.

This idea was made by focusing on these conventional problems, and it is a shock absorber that is interposed between the vehicle body and the driving wheels that can transmit the rotation generated by the driven wheels and the prime mover. In addition to using a variable damping force type shock absorber, it includes a rotation speed detection means for detecting the rotation speed of the prime mover, a gear ratio detection means for detecting at least two or more gear ratios among the gear ratios of the transmission, and Comparison means for comparing each of the two or more gear ratios with a prime mover reference rotation speed, which is lower as the gear ratio becomes larger, and a reference whose prime mover rotation speed corresponds to the gear ratio detected by the gear ratio detection means. output means for outputting a signal to increase the damping force of the shock absorber when the comparison means determines that the rotational speed of the prime mover is exceeded, and the damping force of the shock absorber can be changed based on the signal from the output means. It is an object of the present invention to solve the above-mentioned problems by providing a shock absorber device as described above.

This invention will be explained below based on the drawings.

FIG. 2 is a diagram showing an embodiment of this invention.
First, the configuration will be explained. Reference numeral 8 denotes a vehicle body, and an engine 9 as a prime mover is mounted at the front of the vehicle body 8. Wheels 10, 11, 12, and 13 are rotatably supported at the front and rear portions of the vehicle body 8, and the engine 9 and the wheels 12, 13 are connected by a transmission 14 and a propeller shaft (not shown). ing. Wheels 10-1
Known variable damping force type shock absorbers 15, 16, 17, and 18 are respectively interposed between the shock absorber 3 and the vehicle body 8.
The damping force changing means 18 are connected to a control unit 19. Control unit 1
9 is connected to an engine rotation speed sensor (rotation speed detection means) 20 which is connected to the ignition device of the engine 9 and is capable of transmitting an ignition pulse signal according to the number of times the ignition device ignites. A gear position sensor (speed ratio detection means) 21 that detects the speed ratio of the transmission 14 is connected.

As shown in detail in FIG. 3, the control unit 19 has a D/A transmission 30 that converts the ignition pulse signal from the engine speed sensor 20 into a voltage signal. 3
0 can transmit voltage signals to the comparators 31, 32, 33, and 34, respectively. Each comparator 31 to 34 outputs a voltage signal to AND circuits 35, 36, 3 when the engine 9 reaches a predetermined rotation speed and the voltage signal exceeds a reference value.
7, 38, and each comparator 31 to 34
The reference voltage of transmission 14 is the first speed,
A value corresponding to the rotational speed of the engine 9 (corresponding to the reference engine rotational speed) at which the damping force of the shock absorbers 15 to 18 needs to be switched to a large value when it is in the 2nd, 3rd, and 4th speeds. is set to . Here, the relationship between the vehicle speed and the engine speed when the transmission 14 is in the first to fourth speeds is shown by straight lines 39 to 4 in FIG. 4, respectively.
2. In this case, in this embodiment, the reference voltages of the comparators 31 to 34 are set to different values for all gear ratios (first to fourth gears), and in particular, the larger the gear ratio, the lower the reference engine voltage. The number of revolutions is determined. Therefore,
This is shown in Figure 4 as a change in damping force.
Points 43 to 46 indicated by black circles are the respective changes corresponding to the first to fourth speeds. As is clear from the figure, as indicated by the broken line X, the reference engine speed increases sequentially from the first gear to the fourth gear. In this way, by appropriately selecting the reference voltages of the comparators 31 to 34, the change point 43 of the damping force can be adjusted.
~46 can be selected. Note that the reference engine speed may be set to a different value for each gear ratio as in the above example, but is not limited to this. For example, depending on the vehicle, the same value may be set for the first and second speeds, The third and fourth speeds may be set to the same value, different from those of the first and second speeds, and may be appropriately determined depending on the characteristics of the vehicle. However, even in this case, the larger the gear ratio is, the lower the reference engine speed becomes.

The AND circuits 35 to 38 are connected to the gear position sensor 21, and the gear position sensor 2
1 is connected to Hall elements 47, 48, 49, and 50 connected to each AND circuit 35 to 38, respectively, and to an operating lever of the transmission 14, so that when the transmission 14 is switched from 1st speed to 4th speed, It has a permanent magnet 51 that can be brought close to any of the Hall elements 47 to 50. Therefore,
AND circuits 35 to 38 are transmission 14
is located in one of the first to fourth speeds, and when the rotational speed of the engine 9 exceeds a predetermined rotational speed (the above-mentioned reference engine rotational speed) in the first to fourth speeds, a voltage signal is generated. . Each AND circuit 35-3
8 is an off-delay relay 53 via an amplifier 52
This off-delay relay 53
The shock absorber 1
The time constant is set so as to prevent the damping force from 5 to 18 from suddenly changing and causing sudden behavior of the vehicle. Off-day relay 53 is relay 54
is connected to the solenoid 55 of the relay 54.
When the solenoid 55 is excited, the first contact 56 is switched to the second contact 57, and the damping force of each shock absorber 15-18 can be switched from a small value to a large value. Note that the comparator 31,
32, 33, and 34 constitute comparison means, and AND circuits 35, 36, 37, and 38 constitute output means.

Next, the effect will be explained.

First, when starting the vehicle, the transmission 14 is placed in first gear. At this time, the gear position sensor 21 detects that the gear ratio is in the first speed, and sends a voltage signal to the AND circuit 35.
Furthermore, since the transmission 14 is at a position with a large gear ratio, the engine 9 rotates at high speed. As a result, the D/A converter 30 generates a high voltage,
A signal is generated in the comparator 31 corresponding to the gear ratio of the first speed. At this time, when the comparator 31 determines that the rotation speed of the engine 9 exceeds the reference engine rotation speed in the first speed, it causes the AND circuit 35 to generate a voltage signal. Therefore, a voltage signal is generated from the AND circuit 35 to the amplifier 52, and the amplifier 52 excites the solenoid 55 of the relay 54, and the second contact 5
The high voltage signal from 7 is sent to the shock absorber 15~
The damping force changing means 18 increases the damping force of the shock absorbers 15-18. In this way, even if the vehicle speed is not detected, the damping force of the shock absorbers 15 to 18 increases when the vehicle starts by comparing it with the reference engine speed corresponding to the first gear. The reference engine rotation is set to a standard engine rotation suitable for the first gear position (first gear position), thereby preventing the vehicle from sinking. Note that the above effect can be obtained without detecting the vehicle speed in the following cases as well.

Next, while the vehicle is moving straight at low speed, the transmission 14 is switched to a small gear ratio.
Moreover, the rotation speed of the engine 9 is low. Therefore,
D/A converter 30 is generating a low voltage and comparator 32 does not output a signal. As a result, the relay 54 is at the first contact 56 and the voltage signal sent from the first point 56 to the damping force changing means of the shock absorbers 15-18 is low. Therefore, the damping force of the shock absorbers 15 to 18 is small, and the ride comfort of the vehicle is improved.

Next, if you downshift and use engine braking while driving, the vehicle will go straight from high speed to low speed, the transmission 14 will change to a large gear ratio, and the engine speed will increase, but the gear position will change. The damping force of the shock absorbers 15 to 18 increases because the engine speed is compared with the reference engine speed corresponding to the gear ratio detected by the sensor 21 and the damping force is changed as the engine speed increases. Therefore, even when downshifting and using engine braking, nose dive (sinking of the vehicle body 8 in the forward direction) can be prevented. Additionally, when a vehicle downshifts while turning and turns, a lower gear ratio is usually selected compared to when the vehicle is traveling straight, even at the same vehicle speed, and the engine speed increases. Since we are comparing the engine speed and the engine speed, the shock absorber 1
The damping forces 5 to 18 are increased, and rolling of the vehicle body 8 can be suppressed even if a large centrifugal force is applied to the vehicle body 8.

Although this embodiment has the above-mentioned effects even without detecting the vehicle speed, it is assumed that the vehicle speed is detected and the engine speed is below a certain value and the engine speed is above a certain value regardless of the gear ratio (or the engine speed is It is also possible to change the damping force under the condition that the number of changes exceeds a certain range. However, in such a case, although the vehicle speed parameter can be used in combination, since the standard engine speed is a single value regardless of the gear ratio, it is possible to obtain the same effect as the scuff prevention in the above-mentioned embodiment. However, it is not possible to achieve the effect of suppressing rolling (that is, improving stability while driving) due to gear ratio selection while driving. in this way,
In this embodiment, since the reference engine speed is changed for each gear ratio, it is possible to improve not only the skirting but also the stability during running due to the gear ratio selection.

Next, when the vehicle is traveling at high speed, the transmission 14 is switched to a small gear ratio.
In this case, the engine speed is sufficiently high even in the highest gear, so the D/A converter 30 generates a high voltage. At this time, gear position sensor 2
1 detects that the gear ratio of the transmission 14 is at a high position. As a result, the amplifier 52 excites the solenoid 55 and the relay 54 switches to the second contact 57. Therefore, the damping force of the shock absorbers 15 to 18 becomes large, and the stability of the vehicle body 8 during high-speed running can be ensured as before.

As explained above, according to this idea,
In a shock absorber device including a shock absorber interposed between a drive wheel and a vehicle body to which rotation generated by a driven wheel and a prime mover can be transmitted, the shock absorber is a variable damping force type shock absorber, and a rotation speed detection means for detecting the rotation speed of the prime mover; a gear ratio detection means for detecting at least two or more gear ratios among the gear ratios of the transmission;
Comparison means for comparing each of two or more of the above speed ratios with a reference motor rotation speed, which is lower as the speed ratio becomes larger; and a reference motor whose rotation speed corresponds to the speed ratio detected by the speed ratio detection means. output means for outputting a signal to increase the damping force of the shock absorber when the comparison means determines that the number of revolutions is exceeded, so that the damping force of the shock absorber can be changed based on the signal from the output means. By comparing the engine speed with the reference engine speed according to the gear ratio, the damping force of the shock absorber can be increased when starting, driving, downshifting while cornering, and when driving at high speeds, without having to detect the vehicle speed. This provides the effect that the damping force can be changed appropriately. As a result, the sinking and roll stability of the vehicle body can be improved.

[Brief explanation of the drawing]

FIG. 1 is a schematic perspective view showing a conventional shock absorber device, and FIGS. 2 to 4 are views showing an embodiment of this invention. FIG. Control unit circuit diagram, 4th
The figure is a graph showing the relationship between vehicle speed and engine speed. 8... Vehicle body, 9... Prime mover (engine), 10,
11... Driven wheel, 12, 13... Driving wheel, 15~
18... Variable damping force type shock absorber, 20
...Rotation speed detection means (rotation speed sensor), 21...
Gear ratio detection means (gear position sensor), 31
~34...Comparison means (comparator), 35-38...
Output means (AND circuit).

Claims (1)

[Scope of utility model registration request] In a shock absorber device including a shock absorber interposed between a drive wheel and a vehicle body to which rotation generated by a driven wheel and a prime mover can be transmitted, the shock absorber is a variable damping force type shock absorber, and A rotation speed detection means for detecting the rotation speed of the prime mover; a speed ratio detection means for detecting at least two or more gear ratios among the transmission gear ratios; a comparison means for comparing each gear ratio with a reference prime mover rotation speed, which is lower as the gear ratio is larger; and a comparison means when the prime mover rotation speed exceeds a reference prime mover rotation speed corresponding to the gear ratio detected by the gear ratio detection means. an output means for outputting a signal that increases the damping force of the shock absorber when the shock absorber is determined to be a shock absorber, and the damping force of the shock absorber is changed based on the signal from the output means. absorber device.