JPS61102321A - Differential control device in vehicle - Google Patents

Abstract

PURPOSE:To enhance the accelerating characteristic of a vehicle, by controlling a hydraulic drive means for applying a differential resistant force to a differential limit mechanism through a control means in accordance with an accelerating condition detection signal so that a large torque which is necessary upon acceleration, is transmitted. CONSTITUTION:An accelerator depression amount detecting sensor 41 delivers a detection signal which corresponds to the depressed amount of an accelerator pedal depressed by the driver, to a control circuit 48 composed of a comparating signal generating circuit 49 for delivering a comparing signal Ei corresponding to the detection signal delivered from the sensor 41, a saw-shape wave signal generating circuit 50 for delivering a saw-shape wave signal Et, and a comparator circuit 31 for comparing these signals Et, Ei with each other and delivers a control signal P to a solenoid valve 36 in a hydraulic circuit. In association with the operation of the solenoid valve 36, hydraulic pressure at the hydraulic pressure port of a hydraulic actuator is controlled to have a hydraulic pressure in accordance with the depression amount of the accelerator pedal.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a differential control device for a vehicle that controls the differential resistance force of a differential limiting mechanism in accordance with the acceleration state of the vehicle.

(Prior art) A differential mechanism equipped with a conventional differential limiting mechanism is described, for example, in "Nirasan Service Broadcast" (October 1980, published by Nissan Motor Co., Ltd., pp. 69-71). There are things that have been done.

This conventional differential mechanism ensures smooth maneuverability by allowing differential movement when the vehicle turns and absorbs the difference in rotation between the left and right drive wheels. By creating an effective differential resistive force and limiting the differential operation,
For example, this is provided to facilitate escape of one wheel when it gets stuck in mud or the like with low ground resistance and spins idly.

In the differential limiting mechanism, pressure ring and pinion
Due to the cam action with the mate shaft, a differential resistance force proportional to the torque input from the engine is applied, while when the input torque is small, a differential resistance force corresponding to the preload torque is applied by the disc spring. The structure is such that it is given.

(Problem to be Solved by the Invention) However, in the conventional differential limiting mechanism, the transfer ratio characteristics to the left and right drive wheels are proportional to the input torque due to the pre-set preload torque by the disc springs and the cam action. Because the structure was uniquely determined by the combination of torque proportional to There was a problem that further improvement was not possible. Therefore, for example, if the transfer ratio is set high in advance in order to improve acceleration performance, understeer tendency will be strengthened during high-speed turns, tight corner braking phenomenon and tire stick-slip phenomenon will more likely occur during low-speed turns, and driving performance will be improved. becomes worse and the risk increases. On the other hand, if the transfer ratio is set low in advance, it will be difficult to escape from mud or power slide, and furthermore, the tire pressure will fluctuate as the load applied to the drive wheels increases or decreases. The transfer ratio corresponding to the slip limit cannot be transmitted. Also, conventionally.

Since there is a delay between the acceleration operation and the transmission of engine torque, it has been difficult to further improve the acceleration operation performance.

(Object of the Invention) Therefore, the present invention detects the acceleration state of the vehicle by the acceleration state detection means, and uses this acceleration state detection signal to control the hydraulic drive means that applies differential resistance force to the differential limiting mechanism by the control means. The purpose is to solve the above problems by doing so.

(Means for Solving Problems) The differential control device of the present invention, as shown in FIG. A differential mechanism 1 that distributes and transmits information to left and right drive wheels via the differential mechanism 1 and a differential resistance force generated between the input section and the output section and the two output sections 10
a differential limiting mechanism 12 that limits the differential amount of the vehicle; an acceleration state detection means 40 that detects the acceleration state of the vehicle; and a control means 48 that outputs a control signal based on a detection signal from the acceleration state detection means 40. , comprising a hydraulic drive means 18 for applying a differential resistance force to the differential limiting mechanism 12 according to a control signal from the control means 48, and controlling the differential limiting mechanism 12 to apply a differential resistance force corresponding to the acceleration state. This is what I did.

(Implementation (ri11) Embodiments of the present invention will be described below based on the drawings.

First, a first example will be described.

The vehicle differential control device of this embodiment is shown in FIGS. 2 to 5 (b).
), there is a differential mechanism 1 that distributes and transmits the power input from the engine to the left and right drive wheels where a differential is allowed, and a differential limiting mechanism that limits the amount of differential movement between the left and right drive wheels. 12, acceleration state detection means 40 that detects the acceleration of the vehicle and outputs an analog detection signal, and acceleration state detection means 4.
a control circuit (control means) 4 that outputs a control signal corresponding to the detection signal from 0; and a hydraulic drive means 18 that controls the differential resistance force of the differential limiting mechanism 12 based on the control signal of the control circuit 48; It is made up of.

As shown in FIG. 2, the differential mechanism 1 has an input shaft (
input section) 2 are connected.

A drive pinion 3 is fitted to the end of the input shaft 2, and a driven gear 5 is fixed to the outer periphery of the differential case 4 so as to mesh with the drive pinion 3. The differential case 4 rotates.

A pinion mate shaft 6 is disposed inside the differential case 4 in a direction perpendicular to the axis around which the differential case 4 rotates, and a pair of pinion mate gears 7 are provided at both ends of the pinion mate shaft 6.
(one figure is omitted) is rotatably supported. In addition, inside the differential case 4, a pair of side gears 8 are arranged so as to mesh with both the binion mate gears 7 and coaxially face each other. Left and right drive shafts (output parts) are rotatably supported by a housing 9. 10 so as to be integrally rotatable.

The differential limiting mechanism 12 also includes a binary mate gear 7.
A pressure ring 13 covering the side gear 8 is provided inside the differential case 4. This pressure ring 13 is divided into left and right parts, and a V-shaped groove is provided at each opposing end, and both ends of the pinion mate shaft 6, which has a substantially square cross section, are supported in this groove. In addition, a protrusion formed on the outer circumference of the pressure ring 13 in the axial direction (left-right direction in the figure) is slidably fitted into a groove formed inside the differential case 4, and the pressure ring 13 and the differential case 4 are connected to each other. They can be slid axially relative to each other.

Further, inside the differential case 4, two sets of left and right clutch mechanisms 14 are provided, which are made up of multiple plates and connect the differential case 4 and the shaft portions 8a of the left and right side gears 8.

Each clutch mechanism 14 is provided between the pressure ring 13 and the differential case 4 in the left and right direction (drive shaft 1
It is composed of friction disks 15 and friction plates 16 which are alternately arranged in the axial direction of 0). A protrusion on the inner circumference of the friction disk 15 is slidably fitted into a groove on the outer circumference of the shaft portion 8a of the side gear 8, so that the friction disk 15 can rotate integrally with the side gear 8. On the other hand, the friction plate 16 has a structure in which a protrusion on its outer periphery is slidably fitted into a groove on the inner periphery of the differential case 4, so that the friction plate 16 can rotate integrally with the differential case 4.

As shown in FIG. 2, the hydraulic drive means 18 is a hydraulic actuator 1 that applies pressing force to the clutch mechanism 14.
9 and a hydraulic circuit 29 that supplies hydraulic pressure to the hydraulic actuator 19, and the actuator 19 is connected to each of the left and right clutch/notch mechanisms 14, respectively.

The hydraulic actuator 19 has a reaction plate 20
, a thrust bearing 21, a spacer 22, a bushing rod 23, and a piston 24. The reaction plate 20 is formed into an annular disc and is disposed outside both ends of the differential case 4, and has a plurality of protrusions 20a protruding toward the differential case 4 through holes provided in the differential case 4. It comes into contact with the friction plate 16 by passing through it loosely. Each reaction plate 20 has a thrust bearing 2 on its outer surface.
1 and supported by spacers 22, respectively. Each of these spacers 22 is formed in an annular shape and is attached to the housing 9.
It is housed in an annular i25 provided in the axial direction so as to be slidable in the axial direction. In addition, the housing 9 has an insertion hole 26 that opens the drive shaft 10 at one end in an annular groove on one side shown on the left side in FIG.
A plurality of through holes 2 are formed in the circumferential direction of the
An annular groove 27 is formed in which the other end of the groove 6 is open. The annular groove 27 has an annular piston 24 equipped with a knoll ring.
is inserted, and the piston 24 and spacer 2 are inserted into the insertion hole 26.
A Psoshuro/2 Do edict is inserted loosely to connect 2 and 2.

The housing 9 also has a structure 1 for driving the piston 24.
Two hydraulic boats are provided to introduce oil rE. Therefore, when hydraulic pressure is supplied to the hydraulic port 28 of the hydraulic actuator 19, the piston 24 moves inside the annular groove 27.
moves, and along with this, a pressing force is applied to the friction plate 16 of the clutch mechanism on the left side in the figure via the bushing rod 23, spacer 22, thrust bearing 21, and reaction plate 20. In addition, in the other clutch mechanism 14 shown on the right side of the figure, a pressing force is applied to the spacer 22, thrust bearing 21, and reaction plate 20 by the reaction force of the housing 9 accompanying the movement of the bushing rod 23 driven by the piston 24. Ru.

On the other hand, the hydraulic circuit 29 is connected to the motor 3 as shown in FIG.
A hydraulic pump 31 driven by 0 is connected from a reservoir tank 32 to the hydraulic port 28 of the hydraulic actuator 19 via a check valve 33 and a throttle valve 34,
The output side of the check valve 33 is connected to the reservoir tank 32 through a relief valve 35 and to the reservoir tank 32 through a solenoid valve 36, and a pressure switch 3 is connected to the output side of the check valve 33.
7 are arranged. The solenoid coils of the motor 30 and the solenoid valve 36 are connected to a control circuit (control means) 4, which will be described later, and the motor 30 and the solenoid valve 36 are energized and controlled by a control signal from the control circuit 48. As the motor 30 is driven, the hydraulic pump 3
1 is activated, and the check valve 33 from the reservoir tank 32,
Pressure oil is supplied to the hydraulic boat 28 via the throttle valve 34. The solenoid valve 36 opens the hydraulic port 28 when a control signal from the control circuit 48 is input to the solenoid coil.
The hydraulic pressure of the hydraulic boat 28 is maintained at a high pressure by closing the flow path that communicates with the reservoir tank 32. On the other hand, when a control signal is not input to the solenoid coil, the flow path is conducted to maintain the hydraulic pressure of the hydraulic port 28. lower. When the hydraulic pressure supplied to the hydraulic port 28 is less than the set value, the pressure switch 37 sends a signal to the control circuit 4 and outputs a signal to the control circuit 4.
8 to drive the motor 30. Further, the relief valve 35 is configured to operate when the hydraulic pressure supplied to the hydraulic boat 28 significantly rises above a set value to maintain an appropriate set hydraulic pressure.

In this embodiment, the acceleration state detecting means 40 uses the amount of depression of the accelerator pedal as an acceleration state signal, and includes, for example, an accelerator pedal depression amount sensor 41 such as a potentiometer whose resistance changes in accordance with the depression stroke of the accelerator pedal. It is made up of. The accelerator pedal depression amount sensor 41 outputs an analog electrical signal (detection signal) corresponding to the amount of depression of the accelerator pedal by the driver to the control circuit 48 .

As shown in FIG. 4, the control circuit (control means) 48 converts the analog electrical signal from the accelerator pedal depression amount sensor 41 into a pulse signal through pulse modulation, and based on this pulse signal, the hydraulic drive means 18 It is configured to perform duty control, and is configured by, for example, a microcomputer. That is, the control circuit 48 includes a comparison signal generation circuit 49 that outputs a comparison signal Ei corresponding to an analog electric signal (detection signal) inputted from the accelerator pedal depression amount sensor 41, and a sawtooth-shaped circuit that outputs a mine wave signal Et. The wave signal generation circuit 50 and the mine-like wave signal E
The comparison circuit 51 compares t with the comparison signal Ei and outputs a pulse signal (control signal) P to the solenoid valve A of the hydraulic circuit 29.

The comparison signal generation circuit 49 also includes a reference signal generation circuit 52 that outputs a reference signal for applying a differential resistance force for preload torque, and an analog signal from the accelerator pedal depression and depression amount sensor 41 to this reference signal. It also includes an addition calculation circuit 53 that adds electrical signals and outputs the result as a comparison signal Ei. In the comparator circuit 51, when the comparison signal Ei and the mine wave signal Et as shown in FIG. It is converted into a pulse signal P as shown.

This pulse signal P is converted into a duty ratio corresponding to the magnitude of acceleration since the analog electric signal (detection signal) changes in accordance with the amount of depression of the accelerator pedal. Then, the solenoid valve 36 of the hydraulic circuit 29 performs on/off operations based on this pulse signal P, and accordingly, the hydraulic actuator 19 is duty-controlled, and as a result, the differential resistance force depending on the magnitude of acceleration is changed. It is provided to the movement limiting mechanism 12. Furthermore, when the accelerator pedal is not depressed, a differential resistance force corresponding to the preload torque is applied to the differential limiting a groove 12 by a pulse signal P obtained by converting only the reference signal.

Next, the effect will be explained.

When the accelerator pedal is depressed to accelerate or start while the vehicle is running, the accelerator pedal depression sensor 4
A detection signal that changes from 1 to 1 in accordance with the amount of depression of the accelerator pedal is input to the addition calculation circuit 53 of the control circuit 48. This detection signal is added to the reference signal in the addition calculation circuit 53 and output to the comparison circuit 51 as a comparison signal Ei. In the comparison circuit 51, the comparison signal Ei is converted into a pulse signal P by the mountain wave signal EL from the sawtooth wave signal generation circuit 50, and this pulse signal P is input to the solenoid coil of the solenoid valve 36, and the hydraulic actuator 19 A solenoid valve 36 opens and closes a flow path that connects the hydraulic boat and the reservoir tank 32.

As the solenoid valve 36 operates, the hydraulic pressure of the hydraulic port 28 of the hydraulic actuator 19 is controlled to a hydraulic pressure corresponding to the amount of depression of the accelerator pedal. This hydraulic port 2
8, the piston 2 of the hydraulic actuator 19
4 is activated, and a pressing force is applied to the friction plate 16 of the clutch mechanism 14 via the bushing rod 23, spacer 22, thrust spring 21, and reaction plate 20. When the detection signal from the accelerator pedal depression amount sensor 41 is not detected manually, that is, when the accelerator pedal is not depressed, the pressing force is determined by a differential resistance force corresponding to the preload torque by a pulse signal obtained by converting only the reference signal. It is given as.

In this way, the differential resistance force of the differential limiting mechanism is applied in response to the amount of depression of the accelerator pedal, and the differential limiting amount is determined depending on the magnitude of acceleration, so that the torque is transmitted in proportion to the input torque. Compared to conventional transmission torque, it is possible to transmit a large drive torque to left-right drive vehicles. In other words, the transfer ratio becomes large, and the acceleration performance during acceleration and starting is improved. In addition, since the amount of depression of the accelerator pedal is small during normal turning, the differential resistance force is reduced and differential movement between the left and right drive wheels is allowed, which prevents the problem of increased understeer at high speeds. , it is possible to prevent the occurrence of tight braking phenomena and tire stick-slip phenomena at low speeds, ensuring safe driving. Furthermore, since the differential is limited according to the amount of depression of the accelerator pedal, it is possible to escape from mud or power slide by operating the accelerator pedal by the driver.

Other embodiments will be described below. Note that description of the same parts as in the first embodiment will be omitted.

First, a second example will be described.

In this embodiment, as shown in FIG.
0, the vehicle speed sensor 42, and the differential calculation circuit (differential calculation unit)
43. The vehicle speed sensor 42 is
For example, it consists of a coil that detects changes in the magnetic flux of a magnet that rotates with the speedometer cable.
Outputs vehicle speed as an analog detection signal. The differential calculation circuit 43 is constituted by a calculation amplifier or the like, performs a differential calculation on the detection signal from the vehicle speed sensor 42, and outputs the differential value as an acceleration signal. The acceleration state signal from the differential calculation circuit 34 is sent to the reference signal generation circuit 5 in the addition calculation circuit 53.
It is added to the reference signal No. 2 and output to the comparison circuit 51 as a comparison signal Ei.

Therefore, depending on the magnitude of acceleration, the differential limiting mechanism 12
Since the differential resistance force is controlled, a large drive torque can be transmitted to the drive wheels during acceleration, and the same effect as in the previous embodiment can be obtained.

Next, a third embodiment will be explained based on FIGS. 7 and 8.

In this embodiment, during acceleration and deceleration, the suspension coil springs of the left and right drive wheels expand and contract due to the gravitational acceleration that acts in the longitudinal direction of the vehicle body. The detection signal is used as an acceleration state signal.

For example, to explain the case of an FR vehicle, in this embodiment, the acceleration state detection means 40 is disposed on each of the left and right suspensions of the rear wheels serving as drive wheels, and detects the expansion and contraction displacement of the suspension coil spring. It is composed of a right telescopic displacement sensor 44A, a left telescopic displacement sensor 44B, and an averaging calculation circuit 45 that calculates the average value of the displacement signals from both of these telescopic displacement sensors 44A and 44B and outputs it to the comparison circuit 51 as a comparison signal. There is. Each of the above-mentioned expansion/contraction displacement sensors 44A, 44B may include, for example, a magnet and a magnetoresistive element that changes magnetic resistance according to fluctuations in the magnetic field.
.

The suspension coil spring on the rear wheel side shortens during acceleration, so it outputs a displacement signal whose level increases according to the degree of shortening of the coil spring.
On the other hand, when decelerating, the coil spring expands, so
It has a structure that outputs a displacement signal whose level decreases depending on the degree of expansion of the coil spring.

Therefore, in this embodiment, during acceleration, a displacement signal □ which increases approximately in proportion to the degree of contraction of the coil spring is input from the left and right expansion/contraction displacement sensors 44A, 44B to the averaging calculation circuit 45. The average value of both detection signals is calculated, and this average value is input to the comparison circuit 51 as the comparison signal Ei. Therefore, during acceleration, a differential resistance force corresponding to the degree of shortening of the coil spring is applied to the differential limiting mechanism, making it possible to obtain a larger transfer ratio during acceleration than in the past. For example, as shown in FIG. 8, which shows a transfer torque characteristic diagram, the transfer torque characteristic S during acceleration in this embodiment can be greatly improved compared to the characteristic of a conventional differential limiting mechanism.

On the other hand, when decelerating, the coil spring expands, so
Each telescopic displacement sensor4. IA and 44B output a displacement signal that decreases approximately in inverse proportion to the degree of expansion, and a differential resistance force is applied to the differential limiting mechanism 12 based on the average value of this displacement signal, so that the differential is wide. permissible. Therefore, as shown in the characteristic diagram of FIG. 8, the transfer torque characteristic during deceleration in this embodiment approaches characteristic C of a conventional differential mechanism.

As a result, the transfer ratio can be greatly increased during acceleration, which improves straight-line stability and improves acceleration performance when turning. Furthermore, since the transfer ratio can be significantly reduced during deceleration, it is possible to eliminate the occurrence of tire slip when turning. Furthermore, in this embodiment, by using the amount of expansion and contraction of the coil spring of the drive wheel as an acceleration state signal, it is possible to obtain a transfer ratio that corresponds to the slip limit that increases or decreases with the load applied to the tire.

Next, a fourth embodiment will be described.

Generally, when a differential resistance force is applied to the differential limiting mechanism by a hydraulic drive means, there is a delay in the transmission of hydraulic pressure from the hydraulic drive means, and accordingly, the transfer torque is delayed. Therefore, in this embodiment, in order to prevent this, the accelerator sensor that detects the amount of depression of the accelerator pedal and the differential value of the detection signal output from this accelerator sensor are calculated by a differential calculator, and based on this, the The structure is such that the driving means is controlled.

In this embodiment, as shown in FIG.
0 is composed of an accelerator pedal depression amount sensor 41 and a differential calculation circuit (differential calculation unit) 54 that performs a differential calculation on a detection signal from the accelerator pedal depression amount sensor 41. Then, the differential value from the differential calculation circuit 54 is set to an optimum level by the gain setter 55 in the control circuit 48 to obtain the comparison signal Ei. Note that the differential calculation circuit 54
is composed of an operational amplifier and the like.

In such a differential control device, the comparison signal Ei is determined by the differential value of the accelerator pedal depression amount.
The conversion speed of the pulse signal P is increased, and the timing of the AJ operation of the hydraulic drive means when the accelerator pedal is depressed can be brought forward, making it possible to prevent delays in the transfer torque to the left and right drive wheels. . As a result, the acceleration response is increased, and acceleration performance can be further improved.

As shown in FIG. 10, the comparison signal E is obtained by adding the differential value to the detection signal of the amount of depression of the accelerator pedal.
It can also be used as i, and the same effect as above can be obtained.

Finally, a fifth embodiment will be described.

In this embodiment, the level of the reference signal for applying the differential resistance force equivalent to the preload torque to the differential limiting mechanism is changed to several levels or steplessly, depending on the road surface conditions and the driver's preference. The configuration is such that the transfer ratio can be selected.

For example, a differential control device may be used in which the acceleration state detection means 40 is configured as an accelerator pedal depression amount detection means, and the level of the reference signal that determines the minimum value (preload torque) of the differential resistance force can be switched to three levels. It is shown in Figure 11. This differential control device includes reference signal generation circuits 46A, 46B, and 46C set to different output levels, and a switch that connects each of the reference signal generation circuits 46A, 46B, and 46C to the addition calculation circuit 53 of the control circuit 48. switch 47; and a multiplication calculation circuit 56 that multiplies the reference signal selected by the changeover switch 47 and the detection signal from the accelerator pedal depression amount sensor 41, and outputs the resultant signal as a torque proportional component to the addition calculation circuit 53. It is equipped with The changeover switch 47 is disposed, for example, near the driver's seat so that it can be operated by the driver.

Therefore, the reference level of the pulse signal (detection signal) output from the comparison circuit 51 to the solenoid valve 36 is changed by switching the changeover switch 47, so that the pulse signal (detection signal) output from the comparison circuit 51 to the clutch mechanism of the differential limiting mechanism is changed by the hydraulic actuator 19. The pressing force corresponding to the applied preload torque can be arbitrarily selected from three levels.

In this case, the characteristics of the change in the drive torque transmitted to the left and right drive shafts due to switching are as shown in FIG. 12, for example. FIG. 12 shows the transmissible range of the drive torque transmitted to the left and right drive shafts 10 in accordance with the three-stage switching, and by switching the level of the reference signal, the characteristics shown in FIG.
The transmittable region of the preload torque can be arbitrarily changed as shown by a', b and b', and C and C'. As a result, by changing the changeover switch by the driver, it is possible to select a transfer ratio according to the road surface condition of a rough road or a good road, or according to the driver's preference. For example, on rough roads, if you switch to increase the differential resistance by the amount of preload torque, the differential will be more restricted and sufficient drive torque can be transmitted to the left and right drive wheels, but on good roads, the differential resistance can be increased by the amount of preload torque. By switching the differential resistance to a lower value, the differential is more permissible and problems such as tight corner braking when turning can be resolved. Note that it is not necessary to use as many reference signal generating circuits as the number of switches, and one reference signal generating circuit that can vary the output level is sufficient. Further, the output level of one reference signal generating circuit may be variable steplessly by a volume control or the like. moreover.

This embodiment is not limited to the first embodiment described above, but is applicable to the second to fourth embodiments.
It can be applied to any of the embodiments.

(Effects of the Invention) As described above, according to the present invention, by controlling the differential resistance force of the differential limiting mechanism in accordance with the magnitude of acceleration, the required Since a large drive torque can be transmitted by the left and right drive wheels, the acceleration performance of the vehicle can be improved. In addition, in the first and second embodiments, since the amount of depression of the accelerator pedal is small during normal turns, the differential is allowed, so understeer can be appropriately maintained during high-speed turns, while understeer during low-speed turns can be maintained properly. This prevents the occurrence of tight braking and tire stick-slip phenomena, and also allows the driver to escape from mud and power slide at the same time by operating the pedals. In the third embodiment, since the drive torque corresponding to the slip limit of the evening and the early years can be transmitted, it is possible to improve the turning acceleration performance and the straight-line stability. Furthermore, in the fourth embodiment, absolute control, the responsiveness of the acceleration operation can be increased, so that the acceleration operation performance can be improved. Furthermore, in the fifth embodiment, since the differential resistance force corresponding to the preload torque can be arbitrarily selected, it is possible to obtain a transfer ratio according to the road surface condition such as a rough road or a good road, and the driver's preference. .

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram of the differential control device of the present invention, and FIG.
FIG. 5 tb) relates to the first embodiment of the present invention, FIG. 2 is a vertical sectional view showing a differential mechanism equipped with a differential limiting mechanism and a hydraulic actuator, and FIG. 3 is a schematic configuration diagram showing a hydraulic circuit. ,
FIG. 4 is a schematic configuration diagram showing the acceleration state detection means and control circuit, FIGS. 5(a) and (bl) are waveform diagrams showing the comparison signal, sawtooth wave signal, and pulse signal, and FIG. A schematic configuration diagram showing an acceleration state detection means and a control circuit according to the twelfth embodiment, FIGS. 7 and 8 are the third embodiment of the present invention.
7 is a schematic diagram of the acceleration state detection means and the control circuit, FIG. 8 is a transfer torque characteristic diagram, and FIGS. 9 and 10 are diagrams of the acceleration state according to the fourth embodiment of the present invention. A schematic configuration diagram showing a detection means and a control circuit, respectively;
FIG. 11 and FIG. 12 relate to the fifth embodiment of the present invention,
FIG. 11 is a schematic configuration diagram showing the acceleration state detection means and the control circuit, and FIG. 12 is a characteristic diagram showing the transmissible range of the drive torque transmitted to the left and right drive shafts at the time of three-stage switching. 1 -----1 differential mechanism, 2, io -----1 input section and output section, (+2-
, - differential limiting mechanism, 18-111 - hydraulic drive means, 40 - - acceleration state detection means, 41-111 - accelerator pedal depression amount sensor, 42
．． 43--Vehicle speed sensor and differential calculator, 44A,
44 B ----One right and left telescopic displacement sensor, 45---Averaging calculation circuit, 46A, 46B, 46C152-----Reference signal generation circuit, 47----All changeover switch , 48·=-1~-control means (control circuit), P----
- A control signal.

Claims (6)

[Claims] (1) A differential mechanism that distributes and transmits the engine power input from the input section to the left and right drive wheels via two differentially permitted output sections, and between the input section and the output section. A differential control device for a vehicle is provided with a differential limiting mechanism that generates a differential resistance force to limit the amount of differential between the two output parts, comprising an acceleration state detection means for detecting an acceleration state of the vehicle; A control means for outputting a control signal based on a detection signal from the acceleration state detection means, and a hydraulic drive means for applying a differential resistance force to the differential limiting mechanism based on the control signal of the control means. Characteristic vehicle differential control device. (2) The differential control device for a vehicle according to claim 1, wherein the acceleration state detection means is configured by means for detecting the amount of depression of an accelerator pedal. (3) A vehicle differential according to claim 1, wherein the acceleration state detection means is constituted by a vehicle speed sensor that detects the vehicle speed and a differential calculator that calculates a differential value of a detection signal from the vehicle speed sensor. Control device. (4) The differential control device for a vehicle according to claim 1, wherein the acceleration state detection means is constituted by an expansion/contraction displacement sensor that detects the amount of expansion/contraction of a coil spring of a suspension of a drive wheel. (5) Claim 1, wherein the acceleration state detection means is constituted by an accelerator sensor that detects the amount of depression of the accelerator pedal, and a differential calculator that calculates a differential value of a detection signal from the accelerator sensor. differential control device for vehicles. (6) The control means is provided with a reference level setting means for setting a reference signal level that determines the minimum value of the differential resistance, and the control means is capable of arbitrarily switching the output level of the reference level setting means. A differential control device for a vehicle according to any one of claims 1 to 5, comprising a changeover switch.