KR100551079B1 - Differential device with function limited slip differential and drive control method for the same - Google Patents

Abstract

The present invention relates to a differential device with a differential limiting function that can effectively exhibit the differential limiting function using the hydraulic pressure generated according to the rotational force of the drive shaft.

The present invention relates to a pair of pinion gears rotatably coupled to a pinion shaft installed in a vertical direction in a differential case, a pair of side gears orthogonal to the pinion gear and splined to a drive shaft, and the side gears. And a multi-plate clutch positioned between the differential case and the friction plate of the differential case and the friction disk of the side gear to overlap each other and acting as a clutch, and a pair installed on the drive shaft and driven by the rotational force of the drive shaft. An actuator positioned between the hydraulic pump and the side gear and pushing the side gear outward by the hydraulic pressure generated by the hydraulic pump, and connected between the actuator and the hydraulic pump and according to the hydraulic difference of the hydraulic pump. Of the actuator Hydraulic control means for controlling the drive is configured.

Differential limiter, side gear, hydraulic pump, hydraulic control means, actuator, pressure valve

Description

Differential device with function limited slip differential and drive control method for the same}

1 is an internal configuration of a differential device with a differential limiting device according to the prior art,

2 is an internal configuration of a differential device with a differential limiting device according to the present invention;

3 is an enlarged configuration diagram of A of FIG. 2;

4 is a state diagram when the differential according to the present invention is not differentially limited,

5 is a state diagram when the differential according to the present invention is differentially limited,

<Explanation of symbols on main parts of the drawings>

52: differential case 54: pinion gear

58: drive shaft 60: side gear

62: friction plate 64: friction disk

68: hydraulic pump 70: actuator

72: hydraulic control means 74: connection hose

76a, b: 1st and 2nd chamber 78: pressure plate

80: elastic member 82: pressure valve

The present invention relates to a differential device with a differential limiting function and a drive control method. Particularly, a differential device with a differential limiting function capable of effectively exerting a differential limiting function using hydraulic pressure generated according to a rotational force of a drive shaft and It relates to a drive control method.

In general, a vehicle, a clutch, a transmission, and a differential are used to properly transmit power generated from an engine to a wheel. At this time, the front engine front wheel drive (FF) vehicle directly connects the output from the transmission to the differential, and the front engine rear wheel drive (FR) vehicle delivers the output from the transmission to the differential through the propulsion shaft.

Here, the differential device is a device for smoothly changing the direction of the vehicle by changing the number of revolutions of the left wheel and the right wheel when the vehicle is turning, and also to ensure the driving safety of the vehicle on the uneven road surface.

In order to improve the differential device as described above, when the frictional force difference of the road surface in contact with the wheel becomes large, the wheel on the side with the lower frictional force is idle and the wheel on the side with the higher frictional force stops, making it difficult to operate the vehicle normally. A differential limiter is fitted.

1 is an internal configuration of a differential device with a differential limiting device according to the prior art.

As shown in FIG. 1, a differential device having a conventional differential limiting device is rotatably installed in the differential case 2 and the differential case 2 which are rotated by the power drawn from the transmission (not shown). A pair of pinion gears 4 which are rotated and rotated, a pinion shaft 6 which fixes the pinion gears 4 to the differential case 4, and a pinion gear 4 which is mounted on a drive shaft 8; And a pair of side gears 10 which are engaged with each other in an orthogonal shape and rotated, a preload spring 12 positioned between the side gears 10 to press the side gears 10, and the side gears ( A multi-plate clutch positioned between 10 and the differential case 8 and arranged so that the plurality of friction plates 14 formed in the differential case 2 and the plurality of friction discs 16 formed in the side gear 10 overlap each other. Including 18 It is sex.

Here, the friction plate 14 is splined to the differential case 2, the friction disk 16 is splined to the side gear 10 and is disposed between the plurality of friction plates 14, respectively. .

The preload spring 12 forms a preload of a predetermined magnitude to push the side gear 10 outward so that a differential limit torque (TBR) that limits the differential is easily generated.

That is, the friction disk 16 is in contact with the friction plate 14 while the side gear 10 is moved outward, and a predetermined friction force is caused by the clutch action of the friction plate 14 and the friction disk 16. Is generated.

As described above, when the friction plate 14 and the friction disk 16 are kept in a slight contact state, they have little effect on the differential action, but the responsiveness is improved in the differential limiting to increase the differential limit effect. The frictional force is also used as an extra force for the differential limiting torque.

On the other hand, in the differential device, when the vehicle falls into a bog, such as mud, the side of the wheel in the bog becomes a no-load state, and the wheel on the opposite side is in a high load state, and the side gear 10 of the high load state is constrained to rotate. Becomes

In this state, the pinion gear 4 is rotated and rotated at the same time due to the difference in load between the wheels, so that the side gear 10 in the no-load state is rotated at twice as many times as when the pinion gear 4 is only idle. Driven.

Here, the pinion gear 4 is slipped with the side gear 10 of the side that is more resistance due to the difference in the load that the wheel receives from the road surface while pushing the side gear 10 to the outside, the friction disk 16 is Make contact with the friction plate 14.

As described above, the frictional resistance generated by the contact between the friction disk 16 and the friction plate 14 acts as a differential limiting torque to limit the differential.

That is, the rotational force of the differential case 2 is directly transmitted to the drive shaft 8 through the multi-plate clutch 18.

However, the differential device provided with the conventional differential limiting device has a problem in that the structure is very complicated and the maintenance is low, and the maintenance is difficult.

In addition, when the preload spring 12 embedded in the differential device is used for a long time, the elastic force is lowered, and the preloading action is lowered, and the differential limiting ability of the differential limiting device is lowered, thereby reducing the humway escapeability.

Therefore, the conventional differential device requires frequent maintenance to replace the preload spring 12, but there is a problem that the differential limiting device does not function properly because the maintenance is inconvenient and does not occur in a timely manner.

The present invention was created in order to solve the above problems, the object of the present invention by using the hydraulic pressure generated in accordance with the rotational force of the drive shaft, the differential limiting function is effectively exhibited, the maintenance is improved, the differential is easy to maintain To provide a differential device and a drive control method with a limiting function.

The differential device with a differential limiting function of the present invention for realizing the above object comprises a differential case rotated by the power of a transmission, a pair of pinion gears rotatably installed on the differential case, and orthogonal to the pinion gear. A multi-plate clutch comprising a pair of side gears engaged in a shape and respectively coupled to the drive shafts of the left and right wheels, a plurality of friction disks fixed to the side gears and a plurality of friction plates fixed to the differential case, and the left and right wheels A pair of hydraulic pumps respectively installed on the drive shafts of the drive shafts and driven by the rotational force of the drive shafts, and the side gears are moved by the hydraulic pressure of the hydraulic pumps so that the friction disks and the friction plates come into contact with each other. Actuator positioned between the gear and the actuator It is characterized in that it comprises a hydraulic control means connected between the actuator and the hydraulic pump and controls the driving of the actuator according to the hydraulic pressure difference of the hydraulic pump.

In addition, in the drive control method of the differential device with a differential limiting function of the present invention for realizing the above problems, the hydraulic pressure is generated by the first and second hydraulic pumps as the left and right drive shafts are rotated. The first and second stages are transferred to the first and second chambers through the inlet hose, and the pressure plate is horizontally moved by the hydraulic vehicle of the first and second hydraulic pumps, and the hydraulic pressure acting on the pressure plate is the first and second outlet hoses. The second step of recovering the first and second hydraulic pumps through the first and second hydraulic pumps, and the inlet of any one of the first and second outlet hoses is blocked by the pressure plate when the hydraulic difference between the first and second hydraulic pumps is equal to or greater than a predetermined value. A third step in which the pressure valve is opened by the hydraulic pressure, and a fourth step in which the side gear is moved so that the hydraulic pressure is transmitted to the actuator through the pressure valve and the differential limit torque is generated by the friction of the multi-plate clutch. Lure and luggage features.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings.

2 is an internal configuration diagram of a differential device with a differential limiting apparatus according to the present invention, Figure 3 is an enlarged configuration diagram of the A of Figure 2, Figure 4 is not limited differentially in accordance with the present invention 5 is a state diagram when the differential device according to the present invention is differentially limited.

Differential device with a differential limiting function according to the present invention, as shown in Figures 2 to 5, the differential case 52 is rotated by the power drawn from the transmission (not shown), and the differential case 52 A pair of pinion gears 54 provided at an upper portion and a lower portion of the pin, a pinion shaft 56 rotatably fixing the pinion gear 54 to the differential case 52, and orthogonal to the pinion gear 54; A pair of side gears 60 engaged in a shape and splined to the left and right drive shafts 58, and a multi-plate clutch 66 mounted on the side gears 60 and the differential case 52 to act as a clutch. ) And a pair of hydraulic pumps 68 installed on the left and right drive shafts 58 and driven by rotational force of the left and right drive shafts 58, and the hydraulic pressure of the hydraulic pumps 68. By side gear (60) An actuator 70 located between the side gear 60 and the actuator 70 and the hydraulic pump 68 so as to move and operate the multi-plate clutch 66 and the hydraulic pump 68 It is configured to include a hydraulic control means 72 for controlling the drive of the actuator 70 in accordance with the hydraulic difference of the).

Here, the multi-plate clutch 66 is composed of a plurality of friction plates 62 splined to the differential case 52, and a plurality of friction disks 64 splined to the side gear 60, The friction disks 64 are respectively disposed between the friction plates 62 such that the friction plates 62 and the friction disks 64 alternate with each other.

The drive shaft 58 includes a first drive shaft 58a and a second drive shaft 58b respectively connected to the left and right wheels of the vehicle, and the hydraulic pump 68 includes the first drive shaft 58a. It consists of a 1st hydraulic pump 68a installed in the 2nd hydraulic pump 68b provided in the 2nd drive shaft 58b.

The hydraulic pump 68 is driven by the rotational force of the drive shaft 58, the difference in the rotational force of the first and second drive shafts (58a, 58b) are generated in the first and second hydraulic pumps (68a, 68b) This is indicated by the difference in hydraulic pressure.

The hydraulic control means (72) is connected to the first and second hydraulic pumps (68a, 68b) by a connection hose (74) is installed in the case 76 and the case 76, the fluid flows in or out; The pressure plate which divides the inner space of the case 76 into the first chamber 76a and the second chamber 76b and moves horizontally according to the pressure difference between the first chamber 76a and the second chamber 76b ( 78, an elastic member 80 installed between the pressure plate 78 and the case 76 to elastically support the pressure plate 70, and the actuator according to the internal pressure of the case 76. And a pressure valve 82 provided in each of the first chamber 76a and the second chamber 76b of the case 76 to control the flow of the fluid flowing into the 70.

The connection hose 74 includes first connection hoses 84a and 86a connecting the first chamber 76a and the first hydraulic pump 86a, and the second chamber 76b and the second hydraulic pump 86b. ) And second connection hoses (84b, 86b) for connecting.

The first connection hoses 84a and 86a may include a first inlet hose 84a through which fluid flows from the first hydraulic pump 68a into the first chamber 76a and the first chamber 76a in the first chamber 76a. A first outflow hose 86a through which the fluid flows out to the first hydraulic pump 68a.
The second connection hoses 84b and 86b may include a second inlet hose 84b through which the fluid flows from the second hydraulic pump 68b into the second chamber 76b and the second chamber 76b. A second outflow hose 86b through which the fluid flows out to the second hydraulic pump 68b.

Therefore, the first chamber 76a and the second chamber 76b have the inlets 88a and 88b of the first and second outlet hoses 86a and 86b and the first and second inlet hoses 84a and 84b, respectively. The outlet portions 90a and 90b are formed to face each other, and the inlet portions 88a and 88b of the first and second outlet hoses 86a and 86b are formed at positions facing each other with respect to the pressure plate 78. do.

In particular, the inlets 88a, 88b of the outlet hoses 86a, 86b should be located within the range in which the pressure plate 78 is moved.

The pressure plate 78 is a plate-shaped member installed in the case 76 so as to be movable to both sides. The pressure plate 78 is installed to prevent the leakage of fluid between the first chamber 76a and the second chamber 76b. Hydraulic pressure of the first chamber 76a and the second chamber 76b is applied.

The pressure plate 78 is moved in one of the left and right directions by the pressure difference between the first chamber 76a and the second chamber 76b, and the pressure difference between the first and second outlet hoses is greater than or equal to a predetermined value. The thickness t of the pressure plate 78 is formed larger than the diameter r of the inlets 88a and 88b so that the inlets 88a and 88b of the 86a and 86b are blocked.

That is, the inlet portions 88a and 88b of the first and second outlet hoses 86a and 86b are formed by the pressure plate 78 according to the pressure difference between the first chamber 76a and the second chamber 76b. Optionally blocked.
The set value is a pressure difference in which one of the left and right drive shafts 58a and 58b is subjected to a very large load and at the same time a very small load is applied to the other.

A support rib 92 is formed in the case 76 to face the pressure plate 78, and the support rib 92 does not interfere with the movement of the pressure plate 78. Outside of the range of motion.

On the other hand, the elastic member 80 is a return spring disposed between the side of the pressure plate 78 and the support ribs 92, it is disposed on both sides of the pressure plate 78 so that the pressure plate 78 is It elastically behaves and returns to the minimum position when the pressure difference is resolved.

In addition, one side of the first chamber (76a) and the second chamber (76b) is formed with a hole in which the pressure valve 82 is installed, the hole is located outside the movement range of the pressure plate (78).

A pressure hose 94 connected to the actuator 70 is installed outside the hole, and when the pressure valve 82 is opened, the pressure hose 94 draws fluid inside the case 76 to the actuator 70. ).

The pressure valve 82 is provided with a housing 96 fixed to the hole, a valve 98 installed in the housing 96 and opened and closed according to the internal pressure of the case 76, and the valve 98. It is composed of an opening and closing spring 100 installed between the housing 96 to elastically support the valve 98.

Accordingly, the pressure plate 78 is moved in the direction of low hydraulic pressure in the first chamber 76a and the second chamber 76b, so that the inlet portions 88a and 88b of the first and second outlet hoses 86a and 86b are moved. When one of the blocks is blocked, the internal pressure of the case 76 is increased, and the fluid of the fluid flows out into the pressure hose 94 through the pressure valve 98.

The actuator 70 has a cylinder 102 in which the pressure hose 94 is connected and fluid is introduced thereto, and an opening is formed in the direction of the side gear 60, and the side gear is formed by an internal hydraulic pressure of the cylinder 102. It consists of a pair of pistons 104 movably installed in the opening of the cylinder 102 so that 60 is moved.

On the other hand, when the side gear 60 is moved to the outside by the piston 104 of the actuator 70, a plurality of friction disks 64 formed on the side gear 60 is in contact with the friction plate 62, respectively. In addition, a differential limiting torque (TBR, Torque Bias Ratio) is formed to limit the differential due to the frictional action of the friction plate 62 and the friction disk 64.

Looking at the operation of the differential device with a differential limiting function according to the present invention configured as described above are as follows.

First, the first hydraulic pump 68a and the second hydraulic pump 68b are driven by the rotational forces a and b of the first drive shaft 58a and the second drive shaft 58b, respectively. d) will be generated.

The generated hydraulic pressures (c, d) are the first chamber 76a and the second chamber 76b of the hydraulic control means 72 through the first inlet hose 84a and the second inlet hose 84b through the fluid. ), And the movement of the pressure plate 78 is adjusted according to the difference in the hydraulic pressure (c, d) received.

On the other hand, when the vehicle goes straight with the road surface evenly, the left and right wheels are rotated the same, and if the road is uneven or the vehicle turns, a certain speed difference occurs in the left and right wheels.

As described above, when the left and right wheels are rotated in the same manner, the difference in the hydraulic pressures (c, d) of the first chamber 78a and the second chamber 78b is the same, and the pressure plate 78 maintains a stationary state. When a difference in speed occurs in the left and right wheels, the pressure plate 78 is moved a predetermined distance in one direction due to a difference in the hydraulic pressures c and d of the first chamber 78a and the second chamber 78b. The hydraulic pressure difference such that the inlet portions 88a and 88b of the hose 86a and the second outlet hose 86b are blocked does not occur.

Accordingly, the fluids c and d of the first chamber 76a and the second chamber 76b are transferred to the hydraulic pumps 68a and 68b through the first outlet hose 86a and the second outlet hose 86b. Each is recovered.

On the other hand. When the vehicle falls into a bog such as mud, the wheels in the bog become unloaded, and the wheels on the opposite side are in a high load state, and a very large speed difference occurs between the left and right wheels of the vehicle.

That is, since the hydraulic pressure difference between the first chamber 76a and the second chamber 76b is greater than the elastic force of the elastic member 80, the pressure plate 78 has a relatively large hydraulic pressure (g, h) It is moved in a small direction.

When the pressure plate 78 is moved to the second chamber 76b, the inlet portion 88b of the second outlet hose 86ab is blocked by the pressure plate 78 so that the second hydraulic pump ( The size of the hydraulic pressure h is increased by 68b), and when the size of the hydraulic pressure h becomes higher than a predetermined level, the pressure valve 82 is opened.

When the pressure valve 82 is opened as described above, the fluid inside the case 76 is transferred to the cylinder 102 of the actuator 70 through the pressure hose 94 to transmit the hydraulic pressure h.

As the hydraulic pressure h of the cylinder 102 is increased, the actuator 70 pressurizes the side gear 60 disposed on both sides, and the side gear 60 has a piston ( When moved outwardly by 104, the friction disk 64 is pressed against the friction plate 62.

The friction plate 62 and the friction disk 64 have a frictional action to generate a differential limit torque, and the differential limit torque causes the side gear 60 and the differential case 52 to be operated integrally to provide a differential. Will be limited.

Differential device and drive control method with a differential limiting function of the present invention configured as described above is a hydraulic pump is driven by the rotational force of the drive shaft and differential to limit the operation of the differential device using a hydraulic vehicle generated from the hydraulic pump Since a limited torque is generated, the differential limiting function is excellent, and therefore, there is an advantage in that the humlog escapeability and the climbing performance are improved.

In addition, since the preload spring used in the conventional differential limiter is not required, there is an advantage of preventing frequent maintenance and durability degradation of the differential limiter due to the preload of the preload spring.                     

In addition, the improvement of the durability and the reduction of the maintenance frequency as described above improves the merchandise of the differential limiting device, and improves the maintainability compared to the prior art, thereby maintaining the effect of easy maintenance.

Claims (12)

A differential case rotated by the power of the transmission; A pair of pinion gears rotatably installed in the differential case; A pair of side gears meshed with the pinion gear in an orthogonal shape and respectively coupled to the drive shafts of the left and right wheels; A multi-plate clutch comprising a plurality of friction disks fixed to the side gear and a plurality of friction plates fixed to the differential case; A pair of hydraulic pumps installed on the drive shafts of the left and right wheels and driven by the rotational force of the drive shaft; An actuator positioned between the pair of side gears such that the friction disk and the friction plate come into contact with each other by the hydraulic pressure of the hydraulic pump; And a hydraulic control unit connected between the actuator and the hydraulic pump and configured to control driving of the actuator according to the hydraulic pressure difference of the hydraulic pump. The method of claim 1, The hydraulic control means is connected to the hydraulic pump by a connection hose and the fluid flows in and out; A pressure plate installed in the case to divide the inner space of the case into a first chamber and a second chamber and horizontally moved according to a pressure difference between the first chamber and the second chamber; An elastic member for elastically supporting the pressure plate; And a differential valve provided in the first chamber and the second chamber, respectively, and configured as a pressure valve for regulating hydraulic pressure by intermittent the flow of the fluid flowing into the actuator. The method of claim 2, The hydraulic pump is composed of a first hydraulic pump and a second hydraulic pump installed on the drive shaft on the left and right, The connection hose comprises a first connection hose connecting the first chamber and the first hydraulic pump, and a second connection hose connecting the second chamber and the second hydraulic pump. Differential device. The method of claim 3, wherein The first and second connection hoses include first and second inflow hoses through which the hydraulic pressure of the first and second hydraulic pumps respectively flow into the first and second chambers, and the hydraulic pressure of the first and second chambers is the first and second hydraulic pressures. Differential device with a differential limiting function, characterized in that consisting of the first and second outlet hoses, each pumped out. The method of claim 4, wherein Differential device with a differential limit function, characterized in that the outlet and the pressure valve of the first and second inlet hose is formed outside the movement range of the pressure plate. The method of claim 5, The inlet of the first and second outlet hoses is provided with a differential limiting function, which is formed within the moving range of the pressure plate so that the pressure plate can be blocked by the pressure plate when the pressure difference between the first and second chambers is higher than a predetermined level. Differential device. The method of claim 6, The pressure plate has a differential limiting function, characterized in that the contact surface with the casing is formed with a larger area than the inlet of the first and second outlet hoses. The method of claim 7, wherein The inside of the first and second chambers, the support ribs are formed in a position opposite to the pressure plate center, the elastic member is provided with a differential limiting function, characterized in that installed between the pressure plate and the support ribs. The method according to any one of claims 2 to 8, The pressure valve may include a housing fixed to a hole formed in each of the first and second chambers of the case, a valve that is opened and closed according to internal pressures of the first and second chambers, and installed between the valve and the housing. Differential device with a differential limit function, characterized in that consisting of an opening and closing spring to be opened and closed sexually. The method of claim 9, The differential device with a differential limit function, characterized in that the pressure hose is installed between the pressure valve and the actuator for transmitting the hydraulic pressure. The method according to any one of claims 2 to 8, The actuator comprises a cylinder that receives hydraulic pressure by the hydraulic control means, and a piston that is movably installed at a portion opposed to the side gear to move the pair of side gears outward by the hydraulic pressure of the cylinder. Differential device with a differential limiting feature. A first step in which hydraulic pressure is generated by the first and second hydraulic pumps as the left and right drive shafts are rotated and transferred to the first and second chambers through the first and second inlet hoses; A second step in which the pressure plate is horizontally moved by the hydraulic vehicle of the first and second hydraulic pumps and the hydraulic pressure acting on the pressure plate is recovered to the first and second hydraulic pumps through the first and second outlet hoses; A third step in which an inlet of any one of the first and second outlet hoses is blocked by the pressure plate when the hydraulic pressure difference between the first and second hydraulic pumps is equal to or larger than a set value, thereby opening the pressure valve by the hydraulic pressure; And a fourth step in which the side gear is moved so that the hydraulic pressure is transmitted to the actuator through the pressure valve and the differential limit torque is generated by friction of the multi-plate clutch.

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