KR20150004107A

KR20150004107A - transfer for 4 wheel drive vehicle

Info

Publication number: KR20150004107A
Application number: KR1020130077149A
Authority: KR
Inventors: 김진우
Original assignee: 현대다이모스(주)
Priority date: 2013-07-02
Filing date: 2013-07-02
Publication date: 2015-01-12

Abstract

The present invention relates to an auxiliary transmission of a four-wheel drive vehicle, in which an oil pump is integrally formed on an inner surface of a boss portion of a rear case, a bearing for supporting a rear end of a rear output shaft is provided on an outer surface of the boss portion, The number of parts and the number of assemblies of the pump can be reduced, and the bearing can be replaced without detaching the rear case.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a four-

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an auxiliary transmission of a four-wheel drive vehicle, and more particularly to a sub-transmission of a four-wheel drive vehicle that switches between a two-wheel drive state and a four-wheel drive state.

The driving method of the vehicle is largely a two-wheel drive system and a four-wheel drive system. The two-wheel drive system drives only the front wheels or the rear wheels, and the four-wheel drive system drives both the front wheels and the rear wheels.

The four-wheel drive system is a full-time four-wheel drive system that is always driven by four-wheel drive, and part-time four-wheel drive system that can travel to two- .

Part-time four-wheel drive vehicles are equipped with a secondary transmission to switch between 2-wheel drive and 4-wheel drive.

Korean Patent Laid-Open Publication No. 10-2012-0079567 discloses a vehicle equipped with an auxiliary transmission. 1, the auxiliary transmission 30 is mounted at the rear end of the transmission 20 connected to the engine 10. [ The auxiliary transmission 30 is provided with a rear output shaft 32 and a front output shaft 36 which are selectively interlocked with each other according to the mode selection of the driver. (The mode switching mechanism is omitted.) The rear output shaft 32 The rear output shaft 36 is sequentially connected to the front propeller shaft 60 and the front differential 70. The rear differential shaft 50 is connected to the rear propeller shaft 40 in sequence. Drive shafts are connected to both sides of the rear differential 50 and the front differential 70, and wheels are mounted on the ends of the rear differential 50 and the front differential 70, respectively.

The output of the transmission 20 is normally transmitted to the rear propeller shaft 40 through the rear output shaft 32 and travels in the two-wheel drive state in which only the rear wheels 107 are driven. The output of the transmission 20 is transmitted to the front propeller shaft 60 while the front output shaft 36 is interlocked with the rear output shaft 32 so that the rear wheel 107 is driven In addition, the front wheels 105 are driven to travel in the four-wheel drive state.

2 shows a configuration of a rear-side output end of the auxiliary transmission 30. As shown in Fig. A bearing 33 for supporting the rear output shaft 32 is installed in a state where the rear output shaft 32 protrudes through the rear case 31 of the auxiliary transmission 30, At the rear end of the output shaft 32, a flange 34 for connection with the rear propeller shaft 40 is mounted.

The rear output shaft 32 is provided with an oil pump 35 for lubricating and cooling the rear output shaft 32 and the mechanical elements mounted thereon. The oil pump 35 is disposed between the front case 35a and the rear case 35a, And an inner rotor 35c and an outer rotor 35d provided between them.

The front case 35a and the rear case 35b are bolted to each other and the inner rotor 35c is installed on the rear output shaft 32 and integrally rotated and eccentrically disposed inside the outer rotor 35d. The outer rotor 35d is rotated by the rotation of the inner rotor 35c in an installation space provided in the front case 35a.

Therefore, when the rear output shaft 32 rotates, the inner rotor 35c eccentrically rotates inside the outer rotor 35d, and the pressure difference caused by the space change between the inner rotor 35c and the outer rotor 35d And the discharged oil flows along the oil passage formed in the rear output shaft 32 to lubricate and cool the rear output shaft 32 itself and the mechanical elements mounted thereon.

However, the conventional auxiliary transmission 30 has the following problems.

The number of components of the oil pump 35 is large and the rear case 31 is assembled after the oil pump 35 is preassembled and then mounted on the rear output shaft 32. Therefore, Therefore, quality control of the parts is difficult and assembly becomes troublesome.

Further, the fixed state of the oil pump 35 is not good, and vibration is greatly generated during operation. The oil pump 35 is installed on the rear output shaft 32 in a state of allowing the rotation of the rear output shaft 32. Only the engagement end 35e protruding from the front case 35a is provided in the rear case 31, And is prevented from flowing in the rotating direction, so that the rear output shaft 32 greatly vibrates during rotation. Accordingly, the process of transmitting the engine power through the auxiliary transmission 30 is adversely affected, noise is generated, and the durability of the oil pump 35 is deteriorated.

Since the bearing 33 is mounted on the inner side of the rear case 31 of the auxiliary transmission 30, the rear case 31 must be disassembled in order to replace the bearing 33. Therefore, There was a problem.

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above problems, and it is an object of the present invention to reduce the number of parts of the oil pump, simplify assembly, and securely fix the oil pump, The present invention provides an auxiliary transmission of a four-wheel drive vehicle that is mounted on the outer side and can be easily replaced.

According to an aspect of the present invention, there is provided a transmission case including a rear case coupled to a front case mounted at a rear end of a transmission, a rear output shaft provided in a state of passing through a shaft hole formed at a rear end of the rear case, And an oil pump integrally provided on an inner surface of the boss portion formed in the boss portion.

The oil pump includes an oil pump rear case formed on an inner surface of the boss portion, an oil pump front case mounted on the oil pump rear case portion, and an oil pump front case disposed between the oil pump rear case and the oil pump front case An inner rotor and an outer rotor installed therein.

The inner rotor and the outer rotor are housed in a rotor mounting portion formed in the oil pump rear case, and oil inlet grooves and oil drain grooves are formed on the side surfaces of the rotor mounting portion.

And the inner rotor is eccentrically disposed in an inner space of the outer rotor.

And an oil pipe for supplying oil to the inside of the oil pump is connected to the oil inlet groove.

And the oil discharge groove is connected to the oil passage formed in the rear output shaft so as to supply oil to the main oil passage formed in the rear output shaft.

A seal ring is formed in the oil pump front case and a seal ring is provided in the seal ring to seal between the oil pump front case and the rear output shaft.

A bearing seating portion is formed on the outer surface of the boss portion of the rear case and a bearing for rotatably supporting the rear output shaft is provided on the bearing seating portion so that the bearing can be replaced without disassembling the rear case .

According to the present invention as described above, the number of parts of the oil pump is reduced by replacing one case of the oil pump with a rear case of the auxiliary transmission.

Therefore, the parts management is facilitated and the number of assembling operations is reduced.

Particularly, since the oil pump is assembled to the rear case and the rear case is directly attached to the front case of the auxiliary transmission, there is an effect that the assembly is simplified.

In addition, when the oil pump is integrated with the rear case, the vibration of the oil pump is greatly reduced upon rotation of the rear output shaft. Therefore, since the vibration of the oil pump does not cause the vibration of the rear output shaft, the output of the transmission is smoothly transmitted to the subsequent portion, the noise caused by the vibration is reduced, and the durability life of the oil pump is increased.

Further, since the bearing is mounted on the outer side of the rear case, the bearing can be replaced without disassembling the rear case. Therefore, it is possible to solve the problem of disassembling and reassembling the rear case to replace the bearing.

1 is a schematic view of a four-wheel drive vehicle equipped with an auxiliary transmission;
Fig. 2 is a rear end sectional view of the auxiliary transmission according to the prior art; Fig.
3 is a sectional view of the rear output shaft mounting portion of the auxiliary transmission according to the present invention.
4 is a perspective view showing the inner side of the rear derailleur according to the present invention.
5 is a perspective view of the front case of the auxiliary transmission oil pump according to the present invention.
6 is an assembled state diagram of an inner rotor and an outer rotor of the auxiliary transmission oil pump according to the present invention.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that the invention is not intended to be limited to the particular embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention. Like reference numerals are used for like elements in describing each drawing.

The terms first, second, A, B, etc. may be used to describe various elements, but the elements should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component. And / or < / RTI > includes any combination of a plurality of related listed items or any of a plurality of related listed items.

It is to be understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, . On the other hand, when an element is referred to as being "directly connected" or "directly connected" to another element, it should be understood that there are no other elements in between.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the terms "comprises" or "having" and the like are used to specify that there is a feature, a number, a step, an operation, an element, a component or a combination thereof described in the specification, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the contextual meaning of the related art and are to be interpreted as either ideal or overly formal in the sense of the present application Do not.

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

3 is a sectional view of the rear output shaft mounting portion of the auxiliary transmission according to the present invention.

The auxiliary transmission includes a front case (90) mounted on an output side portion of the transmission case, and a rear case (100) mounted on the front case (90).

A rear output shaft 200 is installed across the space formed by the front case 90 and the rear case 100. [

The front end portion of the rear output shaft 200 is connected to the planetary gear set 80 provided in the space on the front side of the front case 90 and the rear end portion thereof is protruded to the outside through a shaft hole formed in the rear case 100. The periphery of the shaft hole through which the rear output shaft 200 passes is formed as a thickly reinforced boss portion.

An input shaft integrally formed with the sun gear of the planetary gear set 80 is projected forward of the front case 90 and the input shaft is rotatably supported by a bearing provided on the front case 90. [

A rear end portion of the rear output shaft 200 is rotatably supported by a bearing 300 provided in the rear case 100.

As the bearing supporting the front / rear end of the rear output shaft 200, not only the ball bearing as shown but also a simple cylindrical roller bearing or tapered roller bearing can be used.

A flange 400 is installed at the rear end of the rear out shaft 200 protruding outward from the rear case 100.

The flange 400 is inserted into the outer peripheral surface of the rear output shaft 200 and the lock nut 450 is fastened to the end of the rear output shaft 200 to prevent the flange 400 from coming off.

The rear output shaft 200 is provided with an oil pump 500 operated by the rotation of the rear output shaft 200.

The oil pump 500 includes an oil pump rear case shaped portion 110 formed on an inner surface of a boss portion of the rear case 100 (a portion thickly formed to reinforce the periphery of a shaft hole through which the rear output shaft 200 penetrates) An oil pump front case 510 inserted into an outer circumferential surface of the rear output shaft 200 and coupled to the oil pump rear case configuration 110 and an oil pump front case 510 inserted into the oil pump rear case configuration 110 and the oil pump front case 510 And an inner rotor 520 and an outer rotor 530 installed between the outer rotor 530 and the outer rotor 530.

4, the oil pump rear case-like portion 110 formed in the boss portion of the rear case 100 includes a case joint surface 111 to which the oil pump front case 510 is closely fitted, A rotor mounting portion 112 formed at a lower level with a step inside the rotor mounting portion 112 to provide a space for installing the inner rotor 520 and the outer rotor 530; And an oil discharge groove 114. The oil discharge groove 113 is formed in a substantially cylindrical shape.

3, 4 and 6, one end of the oil inflow groove 113 is connected to an oil pipe 540 for supplying oil from the outside to the oil pump 500, 114 is opened to the shaft hole 115 which is in contact with the rear output shaft 200.

An oil passage 210 is formed in a portion of the rear output shaft 200 in contact with the shaft hole 115 so that the oil discharged from the oil discharge groove 114 flows into the main oil passage As shown in Fig.

A plurality of protrusions are formed on the outer circumferential surface of the case contact surface 111, and bolt holes 111a are formed in the protrusions.

5, the oil pump front case 510 has a through-hole through which the rear output shaft 200 passes, at the center of the disk-shaped body 511, A journal portion 512 is formed to protrude in a direction perpendicular to the rear output shaft (axial direction of the rear output shaft), and a plurality of protrusions are formed on the outer circumferential surface of the body 511 and bolt holes 513 are formed in the protrusions.

It goes without saying that the bolt hole 111a of the oil pump rear case 110 and the bolt hole 513 of the oil pump front case 510 have the same number of positions.

A sealing groove 514 may be formed on the inner circumferential surface of the oil pump front case 510 to provide a seal ring.

6, the inner rotor 520 has a protrusion 521 and a concave portion 522 repeatedly formed on the outer circumferential surface, a through hole through which the rear output shaft 200 passes, A serration 523 is formed on the inner circumferential surface of the through hole so as to engage with the rear output shaft 200 to constrain the behavior in the axial rotation direction.

The outer rotor 530 has a shape in which the protrusion 531 and the recess 532 are continuously and repeatedly formed on the inner circumferential surface of the inner circular space into which the inner rotor 520 is inserted, And is made to have a finer diameter than that of the inner circumferential surface of the rotor mounting portion 112 so that it can rotate inside the rotor mounting portion 112.

The assembly of the oil pump 500 is performed as follows.

First, an inner rotor 520 and an outer rotor 530 are installed in a rotor mounting portion 112 formed in an oil pump rear case shape portion 110 of the rear case 100. At this time, the outer rotor 530 is inserted first, and the inner rotor 520 is inserted into the inner space of the outer rotor 530.

The oil pump front case 510 is brought into close contact with the case contact surface 111 of the oil pump rear case 110 in a state of covering the side surfaces of the inner rotor 520 and the outer rotor 530, After the holes 513 and 111a are aligned, the bolts are fastened to mount the oil pump front case 510.

Thereafter, the rear case 100 in which the assembly of the oil pump 500 is completed is bolted to the front case 90 of the auxiliary transmission.

At this time, since the center of the inner rotor 520 does not coincide with the center of the outer rotor 530, the tool is inserted at the rear side of the rear case 100 to adjust the position of the inner rotor 520, So that the rear output shaft 200 can be inserted.

When the rear case 100 having the oil pump 500 assembled by inserting the sealing ring 515 into the sealing groove 514 of the oil pump front case 510 is attached to the front case 90, Closing the gap between the oil pump front case 510 and the rear output shaft 200 to seal the oil pump 500. [

On the other hand, the bearing 300 is mounted on the outer surface of the boss portion of the rear case 100. The bearing 300 may be installed at the rear of the rear case 100 to protect the rear end of the rear output shaft 200 protruding outward from the rear case 100 Since the shaft protection guard 120 is formed, it is not exposed to the outside of the outer oil pump 500.

That is, the bearing 300 is press-fitted into the bearing seating portion formed on the outer surface of the boss portion from the rear through the shaft protection guard 120. A retaining groove is formed on the entrance side of the bearing seating portion. After the bearing 300 is press-fitted into the bearing seating portion, a snap ring is provided in the retaining groove to prevent the bearing 300 from being separated.

The bearing 300 may be installed before mounting the rear case 100 to the front case 90 or after mounting the rear case 100 to the front case 90. [

After the bearing 300 is installed, a rotational speed sensing part such as a ton wheel may be selectively installed on the rear output shaft 200 as a means for sensing the rotational speed of the output side of the auxiliary transmission.

A flange 400 for connection with the rear propeller shaft is inserted into the outer peripheral surface of the end of the rear output shaft 200 and the lock nut 450 is coupled to the end of the rear output shaft 200.

In FIG. 4, reference numeral 150 denotes a front output shaft mounting hole; 160, a rotary shaft mounting hole of a motor for driving a mode switching mechanism; and 170, a guide shaft mounting groove in which a mode switching mechanism is installed.

Now, the operation of the present invention will be described.

3, the rear output shaft 200 is connected to the planetary gear set 80 to which the transmission output is input.

The rear output shaft 200 is provided with a drive sprocket 70 for transmitting the rotational force to the front output shaft. The drive sprocket 70 is connected to the driven sprocket provided at the front output shaft by a chain.

A synchronizer 60 is provided on the side of the drive sprocket 70 to selectively couple the drive sprocket 70 to the rear output shaft 200.

The two-wheel / four-wheel switching fork 51 of the mode switching mechanism is connected to the sleeve of the synchronizer 60 and the four-wheel low speed / four-wheel high speed switching fork 52 is connected to the sleeve of the planetary gear set 80 have.

Accordingly, when the drive mode is switched from the two-wheel drive state to the four-wheel drive state by the driver, the synchronizer 60 is operated to interlock the drive sprocket 70 with the rear output shaft 200 so that the transmission output is transmitted to the drive sprocket 70 ), A chain, and a driven sprocket to the front output shaft for four-wheel drive.

Also, when the four-wheel low-speed or four-wheel high-speed mode is selected by the driver, the element engagement state of the planetary gear set 80 is switched and the output through the planetary gear set 80 is decelerated or accelerated, The rotation speed is decelerated or accelerated so that the vehicle can be driven in a four-wheel low-speed or four-wheel high-speed state.

Since the rear output shaft 200 continues to rotate while the output of the transmission is transmitted through the auxiliary transmission as described above, the oil pump 500 mounted thereon is also operated.

When the rear output shaft 200 is rotated, the inner rotor 520 is also rotated integrally. 6, the inner rotor 520 is eccentric with respect to the outer rotor 530, and the outer rotor 530 is rotatably installed in the rotor mounting portion 112, so that the inner rotor 520 ) Can be rotated.

The oil introduced through the oil inlet groove 113 is filled in the space between the inner rotor 520 and the outer rotor 530. When the inner rotor 520 is rotated in this state, The oil moves to the oil discharge groove 114 and the oil is discharged to the oil passage 210 of the rear output shaft 200 through the oil discharge groove 114 by the high pressure formed on the oil discharge groove 114 side. At this time, a relatively low pressure is formed on the side of the oil inlet groove 113, so that the oil flows into the oil inlet groove 113 from the oil pipe 540.

The oil discharged from the oil discharge groove 114 is supplied to the main oil passage formed inside the rear output shaft 200 through the oil passage 210 and discharged from the main oil passage to the respective mechanisms 60, the drive sprocket 70, and the planetary gear set 80) to be lubricated and cooled.

Thus, the oil pump 500 having the structure according to the present invention can smoothly supply the oil for lubrication and cooling to the rear output shaft 200 itself and the mechanisms installed therein.

As described above, the auxiliary transmission according to the present invention has an oil pump that smoothly supplies oil for cooling and lubrication. In addition, the number of components constituting the oil pump is reduced, which is advantageous from the viewpoint of component management, and the number of assembling operations is reduced.

That is, the oil pump rear case is replaced by the oil pump rear case-shaped portion 110 formed in the rear case 100 of the auxiliary transmission, thereby reducing the number of components and the number of assembly operations.

The inner rotor 520 and the outer rotor 530 are installed in the oil pump rear case portion 110 and the oil pump front case 510 is mounted in the oil pump rear case portion 110, The pump 500 is configured so that the oil pump 500 is integrated with the rear case 100 of the auxiliary transmission to maintain a fully fixed state.

Accordingly, the vibration generated in the oil pump 500 and the noise caused thereby are greatly reduced in the operation of the auxiliary transmission.

Accordingly, the influence of the vibration generated in the oil pump 500 on the rotation of the rear output shaft 200 is reduced, so that transmission of the transmission output through the rear output shaft 200 is smoothly performed.

In addition, the durability of the oil pump 500 is improved due to the reduction in vibration, thereby extending the service life of the oil pump 500.

On the other hand, a bearing 300 supporting the rear output shaft 200 is provided on the outer surface of the boss portion of the rear case 100.

Accordingly, when the bearing 300 is defective and needs to be replaced, it is not necessary to disassemble the rear case 100 in the front case 90, and the bearing 300, such as the lock nut 450 and the flange 400, It is possible to replace the bearing 300 simply by removing the parts which are obstructive to detachment of the bearing 300 from the rear of the bearing 200.

The components such as the lock nut 450 and the flange 400 are parts that must be disassembled even when the rear case 100 is detached for replacing the bearing 300. In other words, Do not. That is, according to the present invention, it is not necessary to perform a plurality of bolt disassembly and assembling operations that are required to disassemble and assemble the rear case 100, so that the replacement operation of the bearing 300 can be performed more simply and quickly.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It is understandable. Accordingly, the true scope of the present invention should be determined by the following claims.

100: rear case 110: oil pump rear case configuration part
111: case joint surface 112: rotor mounting portion
113: Oil inlet groove 114: Oil outlet groove
115: Shaft hole 200: Rear output shaft
300: Bearing 400: Flange
500: Oil pump 510: Oil pump front case
520: Inner rotor 530: Outer rotor

Claims

A rear case coupled to a front case mounted at a rear end of the transmission;
A rear output shaft provided in a state of passing through a shaft hole formed at a rear end of the rear case;
An oil pump integrally provided on an inner surface of a boss portion formed around the shaft hole;
And an auxiliary transmission for a four-wheel drive vehicle.

The method according to claim 1,
The oil pump includes an oil pump rear case formed on an inner surface of the boss portion, an oil pump front case mounted on the oil pump rear case portion, and an oil pump front case disposed between the oil pump rear case and the oil pump front case And an outer rotor and an outer rotor installed in the vehicle.

The method of claim 2,
Wherein the inner rotor and the outer rotor are housed in a rotor mounting portion formed in the shape of the rear portion of the oil pump, and an oil inlet groove and an oil drain groove are formed on a side surface of the rotor mounting portion.

The method of claim 3,
Wherein the inner rotor is eccentrically disposed in an inner space of the outer rotor.

The method of claim 3,
And an oil pipe for supplying oil into the oil pump is connected to the oil inlet groove.

The method of claim 3,
Wherein the oil discharge groove is connected to an oil passage formed in the rear output shaft so as to supply oil to a main oil passage formed inside the rear output shaft.

The method of claim 2,
Wherein a sealing groove is formed in the oil pump front case and a seal ring is provided in the sealing groove to seal between the oil pump front case and the rear output shaft.

The method according to claim 1,
A bearing seating portion is formed on the outer surface of the boss portion of the rear case and a bearing for rotatably supporting the rear output shaft is provided on the bearing seating portion so that the bearing can be replaced without disassembling the rear case The auxiliary transmission of a four-wheel drive vehicle featuring.