KR0131248B1 - Four wheel driving device - Google Patents

Abstract

The invention is a front-and-rear differential restrictive device for safety and controllability of a moving vehicle by improving the moving performance of a vehicle by absorbing the speed difference the between the front and rear wheels. depending upon road conditions while four-wheel driving the vehicle. The device comprises a first stage gear that transfers rotational force by connecting to the transfer case; a first cam shaft with a spline formed on the peripheral surface; a means for transferring force to the other end of the first cam shaft; a means for installing and combining with the peripheral surface of the second cam shaft; a housing and an internally installed means for placing the spline at a distance from the spline formed on the first cam shaft by connecting to a propeller shaft in order to drive rear wheels; and a synchronous means so that the rotating cycles of the first & second cam shafts will always be the same.

Description

Front and rear differential limiting device of 4 wheel drive vehicle

1 is a schematic diagram showing an application site of the present invention.

2 is a block diagram according to an embodiment of the present invention.

3 is an operating state diagram showing an operating state of the direction change valve in the normal driving according to the present invention.

Figure 4 is an operating state diagram showing the operating state of the differential limit direction time limit direction switching valve according to the present invention.

[Industrial use]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle differential limiting device. More specifically, a four-wheel drive system for improving safety and maneuverability of a vehicle by improving the stability and controllability of a vehicle by appropriately distributing driving force and absorbing speed processing between front and rear wheels in a four-wheel drive car. A front and rear wheel differential limiting device for a vehicle.

[Prior art]

In general, a four-wheel drive vehicle has excellent stability and maneuverability on a dirt road and on snow or rain by allowing the front and rear wheels to be driven simultaneously. The four-wheel drive vehicle may drive only the front wheel or the rear wheel for economical efficiency, and has a structure capable of simultaneously driving the front and rear wheels as needed. The four-wheel drive vehicle, which is simultaneously driven by the front and rear wheels, maintains an optimal stable state according to road conditions by distributing power to the front wheels and the rear wheels.

[Problems to Be Solved by the Invention]

However, in the four-wheel drive vehicle, there is a difference in driving force and speed applied to the front and rear wheels due to the movement of the load during turning or acceleration and deceleration, and the vehicle. The difference between the driving force and the speed between the front and rear wheels causes a loss of power, and thus, a maximum driving force cannot be obtained. In addition, the difference between the driving force and the speed between the front and rear wheels as described above causes the slip of the wheels and reduces the mobility and acceleration of the vehicle. In particular, there is a problem in that stability and maneuverability cannot be secured during turning.

[Means to solve the problem]

The present invention was created to solve the problems of the prior art as described above, the object of the present invention is to absorb the speed difference between the front and rear wheels according to the conditions of the road when driving the four-wheel drive vehicle to improve the motor performance In addition, the present invention provides a front and rear differential limiting device for a four-wheel drive vehicle that secures driving stability and maneuverability. In order to realize the object of the present invention, one end is connected to the transfer case and the first cam shaft to transmit the rotational force and the spline is formed on the outer peripheral surface, the other end of the first cam shaft is connected by the power transmission means and the outer peripheral surface A second cam shaft having a spline formed thereon, and a spline coupled to the second cam shaft to be splined and fixed to the propeller shaft to drive the rear wheels, and spaced apart from a spline formed on the first cam shaft by a predetermined distance. A four-wheel drive vehicle comprising a housing in which a spline is formed and a synchronous means installed in the housing and operating to obtain maximum driving force in front and rear wheels when the rotational speed of the first and second cam shafts is changed by hydraulic pressure. Provides front and rear wheel differential limiters.

[Action]

The front and rear wheel differential limiting device of the four-wheel drive vehicle of the present invention can differentially limit the front and rear wheels at the time of turning the vehicle, absorb the speed difference between the front and rear wheels, and distribute the driving force appropriately.

EXAMPLE

Hereinafter, with reference to the accompanying drawings, preferred embodiments of the present invention will be described in more detail.

1 is a schematic diagram showing an application state of the present invention, wherein the engine 1, the transmission 3 for transmitting the power of the engine 1, and the power transmitted from the transmission 3 are transferred, A transfer 9 is shown which transfers to the rear wheels 5 and 7. The transfer 9 and the propeller shaft 11 are connected to each other, and the front and rear wheel driving force distribution differential limiting device 13 is interposed therebetween, and the propeller shaft 11 is connected to the longitudinal deceleration gear device 15 to the rear wheel. It is made of a structure for driving. The front and rear wheel driving force distribution differential limiting device 13 is installed on the outer periphery of the first and second cam shafts 17 and 19 and the second cam shaft 19, as shown in FIG. The housing 21 is included. The inner side of the housing 21 is provided with a synchronizing means made of hydraulic pressure so that when the driving force of the first and second cam shafts (17) and (19) is different from each other to act as a complementary structure to obtain the maximum driving force. . The first cam shaft 17 has a structure connected to the shaft for driving the front wheel, the outer peripheral surface is formed with a spline (23). The second cam shaft 19 has a structure in which the first cam shaft 17 and the shaft correspond to each other, and a spline 230 is formed on the outer circumferential surface of the second cam shaft 19. The cam shaft 17 and the shaft have a corresponding structure, and the intermediate portion has a form of a spline 25. The first cam shaft 17 and the second cam shaft 19 are formed of a corresponding shaft. The power transmission means is composed of a cam curve portion 27 in which irregularities are formed on surfaces corresponding to each other, and a plurality of needle balls 29 are inserted into the irregularities to friction each other. The housing 21 has a structure that is coupled to the propeller shaft 11 so as to transmit power to the rear wheels 7 and the spline 31 is formed inside the middle portion of the second cam shaft 19. It has a structure that splines to the middle part of the All.

In addition, the housing 21 has a structure surrounding the outer circumference of the first cam shaft 17. The spline 25 is spaced apart from a portion where the spline 23 of the first cam shaft 17 is formed by a predetermined interval. ) Is formed. The synchronous means is installed in the housing 21 and the first actuator 32 coupled to the second cam shaft 19, and the directional valve 35 connected to the first actuator 32 and the conduit 33 And a second actuator 39 connected to the directional valve 35 and a conduit 37, and a multi-plate clutch 43 contacting the piston 41 of the second actuator 39. The first actuator 32 has a structure in which one end of the second cam shaft 19 and one surface of the piston 45 are fixedly coupled, and the other surface of the piston 45 presses the piston 45 in the axial direction. It has a structure in which the compression elastic member 47 is built. In addition, the outer circumferential surface of the piston 45 has a structure in which the oil seal 49 is inserted and fixed so as to smoothly move during friction contact with the cylinder. In addition, the first actuator 32 has a structure in which oil is inserted therein, which has a structure connected to an oil tank 51 and a conduit 53 installed in the housing 21. On the conduit 53 connecting the oil tank 51 and the first actuator 32, the check valve 55 is mounted so that oil does not flow back into the oil tank 51. The directional valve 35 is also installed in the housing 21 and connected to the first and second actuators 32 and 39 and the conduits 33 and 37, and also the oil tank 51 and the conduit 57. It has a structure that leads to The directional valve 35 is a body 59, a valve spool 61 inherently installed in the body 59 to be movable in an axial direction, and also inserted into the body 59 to provide a valve spool 61. It consists of a structure including a compressive elastic member (63) for holding in the axial direction. The body 59 is branched from the first port 65 connected to the first actuator 32 and the conduit 33 and the conduit 33 connected to the first actuator 32 to communicate with the side It consists of two ports 67, a third port 69 connected to the second actuator 39, and a fourth port 71 connected to the oil tank 57 and the conduit 57. In addition, the pipeline 33 connected to the first port 65 has a structure in which a check valve 73 is installed as shown in FIG. 3 so that oil does not flow back to the first actuator 32. In addition, the conduit 57 connected to the fourth port 71 also has a structure in which a check valve 75 is installed so that oil does not enter the body 59. The valve spool 61 moves in the axial direction by the oil pressure introduced into the second port 67 and selectively opens and closes the first, second, third and fourth ports 65, 67, 69 and 71. The first land 77 to be opened, the second land 79 to selectively open and close the first and third ports 65 and 69 by the movement of the first land 77, and the first land 77 It is made of a structure including a third land 81 for selectively opening and closing the fourth port 71 in accordance with the movement of the). The compression elastic member 63 has a structure in which the valve spool 61 is elastically supported inside the third land 81 and the body 59. The actuator 39 has a structure in which the piston 41 moves in the axial direction by hydraulic pressure, and an oil seal 83 is interposed on the outer circumference of the piston 41 to smoothly move the piston 41. The second actuator 39 has a compressive elastic member 85 interposed therebetween to pressurize the piston 41 on the opposite side to which oil is introduced. It is preferable that four annoying second actuators 39 are provided at 90 ° intervals, but even if two or more are provided at equal intervals, the same effect of the present invention can be obtained. The piston rod 87 is coupled to the piston 41 of the second actuator 39. The multi-plate clutch 43 has a structure arranged in a space between the spline 23 of the first cam shaft 17 and the spline 25 of the housing 21, the inner plate 89 is the first cam shaft In the spline 23 of (17), the outer plate 91 is coupled to the spline 25 of the housing 21 to form a structure that is movable in the axial direction. The multi-plate clutch 43 has a structure in which the piston rod 87 of the second actuator 39 and the outer plate 91 are in contact with each other. In addition, a needle bearing 93 is interposed between the other end of the outer plate 91 and the friction surface friction with the first cam shaft 17, so that the housing 23 and the first cam shaft 17 have a multi-plate clutch ( 43) only in frictional contact. The front and rear differential control device 13 of the four-wheel drive vehicle thus formed is rotated by the same driving force in the front wheel 5 and the rear wheel 7 in a normal state during four-wheel drive driving. The first cam shaft 17 and the second cam shaft 19 related to the driving of the rear wheels 7 have the same rotational force, and the rotation is performed in a state where the unevenness coupled to the shaft is in close contact with each other.

3 is an operation state diagram showing an operation state of the direction change valve in normal driving, and shows a direction change valve 35. The directional valve 35 is connected to the first actuate 32 so that the hydraulic pressure waits at the first port 65 and the second port 67, and the second land 79 is connected to the third, By interlocking the four ports 69 and 71, the oil of the second actuate 39 is introduced into the oil tank 51. Such a state becomes possible because the elastic force of the compression elastic member 63 inherent in the directional valve 35 is greater than the pressure of the first actuator 32. Therefore, the front and rear wheels 5 and 7 are driven without affecting each other. However, when the vehicle turns sharply, the rotational force of the front wheel 5 is increased than the rotational force of the rear wheel 7 so that the rotation of the first cam shaft 17 is faster than the rotation of the second cam shaft 19. At this time, in the cam curve portion 27 of the first and second cam shafts 17, the first cam shaft 17 receives a force to move along the cam curve. In this state, the second cam shaft 19 is relatively reacted to be pushed backward by the force that the first cam shaft 17 tries to move. Therefore, the piston 45 connected to the second cam shaft 19 is pushed back, and the oil in the first actuator 32 is moved to the direction switching valve 35 along the conduit 33.

FIG. 4 is a state diagram showing the operating state of the differential limit time switching valve, and shows the direction switching valve 35. The hydraulic pressure from the first actuator 32 along the conduit 33 is at the first and second ports 65 and 67, and the pressure of the hydraulic pressure of the second port 67 becomes the elastic member 63. To overcome the elastic force of the valve spool 61 is pushed. Then, the second land 79 moves in the direction in which the first and third ports 65 and 69 communicate with each other, and the hydraulic pressure of the first port 65 passes through the second actuator 39 through the third port 69. Is delivered). At this time, the hydraulic pressure transmitted to the second actuate 39 is to overcome the elastic force of the elastic member 85 and push the piston 41. Accordingly, the piston 41 of the second actuate 39 is pushed, and the piston rod 87 fixed to the piston 41 is pushed to press the outer plate 91. The outer plate 91 pushes the inner plate 89 coupled to the first cam shaft 17, thereby making frictional contact. This frictional contact transmits power to the first cam shaft 17 while the first cam shaft 17 and the housing 21 act in a direction of generating driving force by limiting mutual differential to obtain maximum driving force. Accordingly, the second cam shaft 19 and the first cam shaft 17 that are splined to the housing 21 have a differential limit function to obtain a large driving force, and the speed difference between the front wheel 5 and the rear wheel 7 is different. Will absorb. When the first and second cam shafts 17 and 19 have the same rotational force, the direction switching valve 35 returns to the above-described normal driving state. As described above, the front and rear wheel differential limiting device of the four-wheel drive vehicle according to the present invention allows the front and rear wheel differential limiting to occur repeatedly as necessary.

[Effects of the Invention]

The front and rear wheel differential limiting device of the four-wheel drive vehicle according to the present invention can absorb the difference between the speed and the driving force of the front and rear wheels, thereby improving driving stability and maneuverability during turning of the vehicle, thereby improving safety. Can be.

Claims (6)

A second cam shaft, one end of which is connected to the transformer case and transmits rotational force and a spline is formed on an outer circumferential surface thereof, the first cam shaft and the other end of the first cam shaft, connected by a power transmission means, and a spline is formed on an outer circumferential surface thereof; A housing which is installed on the outer circumferential surface of the second cam shaft to be spline-coupled and fixedly coupled to the propeller shaft to drive the rear wheels, the spline being formed at a predetermined distance from the spline formed on the first cam shaft; A front and rear differential limiting device for a four-wheel drive vehicle, which is installed inside the housing and is made of synchronous means such that the rotational speed of the first and second cam shafts is always the same by hydraulic pressure. The four-wheel drive vehicle according to claim 1, wherein the power transmission means comprises a cam curved portion formed by irregularities on the corresponding first and second cam shafts, and a plurality of needle balls installed in frictional contact with the cam curved portion. Front and rear differential limiter. According to claim 1, The synchronizing means is a first actuator is fixedly coupled to the second cam shaft and the piston and the piston is installed so as to be movable in the axial direction, and connected to the pipeline so that oil flows to the first actuator in the reverse direction Is an oil tank interposed with a check valve for blocking oil, a directional valve connected with the first actuator with a check valve interposed with a check valve so that oil does not flow back to the first actuator, and the directional valve and the oil tank. Is connected to the pipeline and between the second actuator communicating with the directional valve via the check valve to prevent oil tank oil from flowing back on the pipeline, the spline formed inside the housing and the corresponding first cam shaft. It is installed to be movable in the axial direction with the inner and outer plates interposed therebetween. The front and rear differential limiting device of a four-wheel drive vehicle is composed of a multi-plate clutch. The front and rear wheel differential limiting apparatus of claim 4, wherein the first actuator is installed therein and includes a compressive elastic member to axially press the second cam shaft. The method of claim 3, wherein the directional telephone valve is connected to the first port and the first port, and the second port and the second cylinder is connected to the side branched from the pipeline connected to the first actuator and the first port; A body including a third port connected to the pipeline and a fourth port connected to the oil tank by the pipeline; A first land that selectively opens and closes the port by hydraulic pressure introduced into the second port, a second land that selectively opens and closes the first port and the third port according to the movement of the first land, and A valve spool including a third land that opens and closes the fourth port according to the movement; A front and rear differential limiting device for a four-wheel drive vehicle, comprising an elastic member interposed between the third land and the body to elastically support the valve spool. The front and rear wheel differential limiting apparatus of claim 3, wherein the second actuator is installed therein and includes a compressive elastic member to axially press the second cam shaft.