KR102291121B1 - Two-steps transmission for vehicles - Google Patents

Abstract

The present invention relates to a two-stage transmission for a vehicle, comprising: an input shaft connected to a driving motor which can rotate normally and reversely; a sun gear provided to rotate with the input shaft; a plurality of planetary gears engaged with the outer periphery of the sun gear; a carrier connecting each of the plurality of planetary gears in a rotatable state; a ring gear provided by allowing the planetary gears to be engaged with the inner periphery thereof; a one-way clutch provided on the ring gear to rotate the ring gear only in the normal direction; a clutch connected to the input shaft to transmit rotational power of the input shaft to the ring gear or block the rotational power; and an output shaft connected to the carrier to transmit the rotational power of the input shaft to wheels while rotating with the carrier. Provided is the two-stage transmission which can perform a first stage driving and a second stage driving, wherein a clutch, in the first stage driving, allows power of a driving motor to be transmitted to the wheels through the input shaft, the sun gear, the planetary gears, the carrier and the output shaft and, in the second stage driving, allows power of the driving motor to be transmitted to the wheels through the input shaft, the ring gear, the planetary gears, the carrier and the output shaft. The present invention minimizes the shock during transmission to enhance driving comfort and reduce wear of parts.

Description

Two-step transmission for vehicles

The present invention relates to a two-speed transmission for a vehicle, and more particularly, to a two-speed transmission for a vehicle comprising a two-speed transmission with a planetary gear set and a wet multi-plate clutch.

Recently, energy saving policies are being promoted due to the depletion of energy resources and the protection of the global environment due to damage such as air pollution and global warming caused by vehicle exhaust. To solve these problems, electric vehicles, hybrid electric vehicles, fuel cell electricity Interest in eco-friendly vehicles such as automobiles is increasing.

Such electric vehicles include not only two-wheeled vehicles such as electric bicycles, scooters, and motorcycles, but also four-wheeled vehicles such as electric wheelchairs and automobiles.

In particular, since the electric vehicle uses electricity as a fuel unlike a gasoline engine, it is a pollution-free vehicle that uses an electric motor as a power source and emits no exhaust gas. , a power transmission structure in which the power of the electric motor is transmitted to the wheel in a decelerated state by this reducer to drive the wheel was mainly used.

However, the electric motor has a characteristic that the torque varies according to the rotational speed (rpm). That is, there is a characteristic of generating the largest torque at the time of initial start-up. When the amount of current is increased to compensate for the torque falling after acceleration, the leaked thermal energy increases, so that the motor efficiency is reduced.

Accordingly, recently, research on a shifting system that extends the mileage of an electric vehicle and improves driving performance by installing a transmission device in an electric vehicle to more efficiently transmit power from the electric motor to the wheel is being actively conducted. .

As described above, a two-speed transmission capable of driving a motor as efficiently as possible is widely used in a shift system configured in place of a speed reducer in an electric vehicle.

However, the conventional two-speed gearbox requires two friction clutches or fluid clutches to implement a two-speed gear stage, thereby increasing the volume of the transmission, and power transmission efficiency due to a sense of power cut, that is, a sense of torque cut. There is a problem with this degradation.

In addition, the conventional two-speed gearbox has a very complicated structure because a number of external gears, locking devices, shift mechanisms, etc. are applied, and the power source of the power source due to the large number of components and the complicated connection structure. There is a problem in that the power loss phenomenon that cannot be transmitted to the output shaft quickly occurs, and the speed change performance is deteriorated.

In particular, in the conventional two-speed gearbox, when shifting from 1st to 2nd gear, shift shock and friction loss occur, which not only reduces riding comfort but also reduces the lifespan of parts, and acts as an obstacle to safe driving. there is a problem.

Republic of Korea Patent Publication No. 10-2016-0005209 Republic of Korea Patent No. 10-1532834 Republic of Korea Patent Registration No. 10-1350772 Republic of Korea Patent Publication No. 10-1997-0046346

Therefore, the present invention has been devised to solve the problems of the prior art as described above, and the power of the motor input through the sun gear by configuring a two-speed transmission with a planetary gear set and a wet multi-plate clutch is applied to the operation of the wet multi-plate clutch. It is an object of the present invention to provide a two-speed gearbox for a vehicle in which two-speed shifting is transmitted to a wheel through an output shaft.

According to the present invention for achieving the above object, there is provided a two-speed transmission for a vehicle, comprising: an input shaft connected to a driving motor capable of forward and reverse rotation; a sun gear provided to rotate with the input shaft; a plurality of planetary gears meshed with the outer periphery of the sun gear; a carrier connecting the plurality of planetary gears in a rotatable state, respectively; a ring gear having a planetary gear meshed with its inner periphery; a one-way clutch provided on the ring gear to rotate the ring gear only in the forward direction; a clutch connected to the input shaft to transmit or block rotational power of the input shaft to the ring gear; 1 stage in which the power of the drive motor is transmitted to the wheel through the input shaft, the sun gear, the planetary gear, the carrier, and the output shaft by the clutch; It features a two-speed transmission capable of running and two-speed running in which the power of the drive motor is transmitted to the wheels through the input shaft, ring gear, planetary gear, carrier, and output shaft.

And, the clutch is connected to the input shaft, the clutch housing rotates together with the input shaft; a clutch friction plate provided to rotate like the clutch housing on the inner periphery of the clutch housing; and a clutch disk provided to rotate like the ring gear on the outer periphery of the ring gear and selectively in contact with the clutch friction plate to transmit or block power to the ring gear.

In addition, the clutch disk may be provided in contact with or separated from the clutch friction plate while being spline-coupled to the outer periphery of the ring gear and moving in the axial direction.

In addition, the clutch disk is provided with a clutch pressure plate for moving the clutch disk while rotating like the clutch disk, and a return spring for returning the moved clutch pressure plate to its original position is provided between the clutch pressure plate and the ring gear. A stopper for stopping the movement may be provided.

In addition, the clutch pressure plate is provided with a cylinder part having a piston that is connected through a release bearing to move the clutch pressure plate, and a master cylinder that moves the piston by supplying hydraulic pressure is connected to the cylinder part and provided, and the master cylinder is fixed. It may be provided to be operated by a reverse-rotating variable speed motor.

In addition, the variable speed motor includes a screw shaft provided to rotate at one end thereof, and a moving block coupled to the screw shaft to convert the rotational motion of the screw shaft into a linear motion, and the moving block is connected to a piston rod provided in the master cylinder. It may be provided to linearly move the piston rod in the master cylinder.

According to the two-speed transmission device for a vehicle of the present invention, the power of the motor is input through the sun gear of the planetary gear set, and the input power is shifted to one or two steps by the wet multi-plate clutch and transmitted to the wheel through the output shaft. The configuration is simple, and the slip of the wet multi-plate clutch can transmit power without cutting power during the shifting process, resulting in excellent power transmission efficiency. there are advantages to

1 is an overall configuration diagram of a two-speed transmission for a vehicle according to the present invention.
2 is a configuration diagram showing the structure of a gear train of a two-speed transmission according to the present invention.
3 is a cross-sectional view of a two-speed transmission according to the present invention.
4 is a three-dimensional view showing the internal structure of the two-speed transmission according to the present invention.
FIG. 5 is a cross-sectional configuration view of FIG. 4 .
6 is a three-dimensional view showing the structure of a planetary gear set of a two-speed transmission according to the present invention.
7 is a view of a first-speed shift state of the two-speed gearbox according to the present invention.
8 is a view during shifting of the two-speed transmission according to the present invention.
9 is a view of a two-speed shift state of the two-speed transmission device according to the present invention.

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

The terms used in the present invention are terms defined in consideration of functions in the present invention, which may vary depending on the intention or custom of the user or operator, so the definitions of these terms correspond to the technical matters of the present invention and should be interpreted as a concept.

In addition, the embodiments of the present invention do not limit the scope of the present invention, but are merely exemplary matters of the constituent elements presented in the claims of the present invention, and are included in the technical spirit throughout the specification of the present invention and the scope of the claims. It is an embodiment including a substitutable component as an equivalent in the component.

In addition, optional terms in the examples below are used to distinguish one component from other components, and the components are not limited by the terms.

Accordingly, in describing the present invention, detailed descriptions of related known technologies that may unnecessarily obscure the gist of the present invention will be omitted.

1 to 9 are views showing the structure and shifting process of a two-speed transmission for a vehicle according to the present invention.

As shown in FIGS. 1 to 3, the two-speed transmission device for a vehicle according to the present invention includes a single planetary gear set and a wet multi-plate clutch 260 between the driving motor 110 as a power source and the wheel 140 as an output source. It is implemented with the configured two-speed transmission 100 .

The two-speed transmission 100 includes a driving motor 110 capable of forward and reverse rotation, an input shaft 210 connected to the driving motor 110 to generate rotational power according to the forward and reverse rotation, and an input shaft 210 . A planetary gear set selectively connected to and transmitting power, a wet multi-plate clutch 260 selectively connecting the planetary gear set and the input shaft 210, and the rotational power of the input shaft 210 through the planetary gear set to the wheel ( It includes an output shaft 250 to transmit to 140).

The driving motor 110 is provided as an electric motor using electricity as energy, which is controlled and driven by the controller 150 .

That is, in order to control the driving motor 110 , the driving motor 110 is provided with a speed sensor 111 that senses its rotational speed and outputs it to the controller 150 , and through the speed sensor 111 , the driving motor ( The controller 150 to which the rotation speed of 110 is input controls the driving motor 110 according to the driving state (ie, driving mode or driving mode) of the vehicle.

In addition, the input shaft 210, the planetary gear set, the wet multi-plate clutch 260, the output shaft 250, etc. are provided in the transmission housing 200, and the transmission housing 200 is filled with oil to operate between each part. It cools the part and reduces frictional resistance at the same time, so shifting is performed smoothly.

An input shaft 210 is through-coupled to one side of the transmission housing 200 , and an output shaft 250 is through-coupled to the other side of the transmission housing 200 .

The input shaft 210 is rotatably coupled to the transmission housing 200 through the input stage bearing 211 as a medium, and the output shaft 250 is also through-coupled to the transmission housing 200 through the output stage bearing 251 as a medium. It is provided rotatably. An oil chamber is provided between each of the bearings 211 and 251 and the transmission housing 200 to seal the transmission housing 200 through which the input shaft 210 and the output shaft 250 pass.

The input shaft 210 has a drive motor 110 connected to one side thereof, and a sun gear 220 of a planetary gear set is provided at the other side thereof.

In particular, the planetary gear set includes one sun gear 220 , a plurality of planetary gears 230 , one ring gear 240 , and one carrier 231 .

That is, as shown in FIGS. 3 to 6 , the planetary gear set includes a sun gear 220 provided to rotate like the input shaft 210 , and a plurality of planetary gears 230 provided to be meshed with the outer periphery of the sun gear 220 . ), a carrier 231 for connecting the plurality of planetary gears 230 in a rotatable state, and a ring gear 240 having a plurality of planetary gears 230 meshed with an inner periphery thereof.

The sun gear 220 configured in the planetary gear set is installed on the outer surface of the input shaft 210 to rotate like the input shaft 210 .

At this time, the sun gear 220 may be integrally formed with the input shaft 210 or may be formed separately and then fixedly provided by a coupling means such as a key coupling, but in this embodiment, FIGS. 3 and 5 . As shown, the former case will be exemplified and described.

In addition, the plurality of planetary gears 230 are provided as three external gears arranged at equal intervals on the outer periphery of the sun gear 220 with the sun gear 220 as a center and meshed with each other. The plurality of planetary gears 230 receive power due to the rotation of the sun gear 220 and rotate (rotate) in the opposite direction to the sun gear 220 and move along the outer periphery of the sun gear 220 to orbit.

At this time, the orbital direction of the planetary gear 230 is moved and rotated in the same direction as the rotational direction of the sun gear 220 .

In particular, the plurality of planetary gears 230 are provided to be all connected by a single carrier 231 , and each planetary gear 230 is rotatably (rotatably) coupled to the carrier 231 in an independent state. .

Accordingly, the plurality of planetary gears 230 are rotated (rotated) in a state coupled to the carrier 231 , and revolved around the sun gear 220 along the outer periphery of the sun gear 220 . ) is rotated in the same direction as the orbital direction of the planetary gear 230 , that is, the sun gear 220 and the rotational direction.

In addition, the carrier 231 is a device that transmits the power of the input shaft 210 to the wheel 140 through an output shaft 250 to be described later, and a plurality of planetary gears 230 are rotatably (rotatably) coupled to one side thereof. and an output shaft 250 to be described later is fixedly connected to the other side of the opposite side. Accordingly, the power of the input shaft 210 is transmitted to the output shaft 250 through the carrier 231 to rotate the wheel 140 .

In addition, the ring gear 240 is provided in a state in which a plurality of planetary gears 230 are meshed and inscribed on the inner periphery thereof.

The ring gear 240 is provided with a one-way clutch 241 for restricting rotation of the ring gear 240 in a forward direction (forward traveling direction) and rotation in a reverse direction (reverse traveling direction). Since the one-way clutch 241 is a technology widely known in various forms in the art, a detailed description thereof will be omitted.

Accordingly, the ring gear 240 is rotated (rotated) in the same direction as the sun gear 220 when the sun gear 220 is rotated in the forward direction, and is fixed in a non-rotatable state when the sun gear 220 is rotated in the reverse direction.

On the other hand, the output shaft 250 is provided such that the carrier 231 is fixedly connected to one side thereof and the wheel 140 is connected to the other side thereof, so that the power of the input shaft 210 is transmitted to the wheel 140 to transmit the power of the wheel 140 to the wheel 140 . ) is provided to rotate.

In addition, a reduction gear 253 is provided between the output shaft 250 and the wheel 140 for decelerating and transmitting the power of the input shaft 210 to the wheel 140 by the driving motor 110 .

In addition, the output shaft 250 is provided with an output speed sensor 252 that detects its rotational speed and outputs it to the controller 150 , and the controller 150 drives the driving motor 110 to the vehicle through the output speed sensor 252 . It is controlled according to the driving state (ie, driving mode or driving mode).

On the other hand, the input shaft 210 is provided with a clutch, that is, a wet multi-plate clutch 260 is connected, and the wet multi-plate clutch 260 transmits or blocks the power of the input shaft 210 to the ring gear 240 of the planetary gear set. provided

As shown in Figs. 4 to 6, the wet multi-plate clutch 260 is connected to the input shaft 210 in a state provided in the transmission housing 200 and rotates with the input shaft 210. A clutch housing 261, The clutch friction plate 262 is provided to rotate like the clutch housing 261 on the inner periphery of the clutch housing 261, and the clutch friction plate 262 is provided to rotate like the ring gear 240 on the outer periphery of the ring gear 240. and a clutch disk 263 for selectively contacting and transmitting or blocking power to the ring gear 240 .

The clutch housing 261 is formed in a “⊂” shape with one surface open, and a planetary gear set is inserted in the clutch housing 261 .

The input shaft 210 is rotatably coupled through the center of the clutch housing 261, and the clutch friction plate 262 is provided on the inner periphery of the clutch housing 261 facing the outer periphery of the ring gear 240, and the clutch friction plate 262 is provided in a multi-plate structure spaced at equal intervals.

In addition, a clutch disk 263 having a multi-plate structure corresponding to the clutch friction plate 262 is provided on the outer periphery of the ring gear 240 .

The clutch disk 263 is spline-coupled to the outer periphery of the ring gear 240 and is provided to be movable in the axial direction of the ring gear 240 while rotating like the ring gear 240 . In particular, the clutch disk 263 may be serrated-coupled to the ring gear 240 , but it is more preferable to form a spline structure having better workability and durability than the serration structure.

Accordingly, the clutch disk 263 is provided to be in contact with or separated from the clutch friction plate 262 while being moved in the axial direction on the outer periphery of the ring gear 240 .

At this time, a stopper 242 for limiting the movement of the clutch disk 263 is provided to protrude from the outer periphery of the ring gear 240, and the stopper 242 is a snap ring that is coupled and fixed to the outer periphery of the ring gear 240. can

On the other hand, the clutch disk 263 as described above is moved by the clutch pressure plate 264 that is moved in the axial direction in the transmission housing 200 , and is returned to its original position by the return spring 266 .

In detail, a speed change motor 120 controlled by the controller 150 and a master cylinder 130 operated by being connected to the speed change motor 120 by a link means are configured, and the transmission housing 200 contains A piston 271 that is linearly moved by hydraulic pressure discharged from the master cylinder 130 is provided.

In particular, a hollow cylinder part 270 is formed inside the transmission housing 200 having the output shaft 250 , and the piston 271 is moved to and from the cylinder part 270 .

In addition, a clutch pressure plate 264 is coupled to the piston 271 entering and exiting from the cylinder unit 270 through a release bearing 265 , so that even when the clutch pressure plate 264 is rotated, the piston 271 does not rotate and the clutch The pressure plate 264 can be moved linearly.

At this time, the cylinder part 270 is provided with only one port through which hydraulic pressure is drawn in and out, and when the hydraulic pressure is supplied by the master cylinder 130, the piston 271 is drawn out and the clutch pressure plate 264 is pushed to push the clutch disk ( 263 ) is brought into contact with the clutch friction plate 262 , and when the clutch pressure plate 264 is returned by the return spring 266 , the hydraulic pressure in the cylinder part 270 is discharged and supplied to the master cylinder 130 .

Accordingly, as the pressing force pushing the clutch pressure plate 264 is released, the clutch disk 263 is naturally separated from the clutch friction plate 262 by the centrifugal force rotated in close contact with the clutch friction plate 262 to block power transmission. do.

The cylinder unit 270 is provided with a hydraulic pressure sensor 272 to sense the hydraulic pressure acting on the cylinder unit 270 , and accordingly, the controller 150 controls the speed change motor 120 and the master cylinder 130 . hydraulic pressure can be controlled.

In addition, the return spring 266 for moving the clutch pressure plate 264 to the original position as described above is composed of a compression coil spring provided between the ring gear 240 and the clutch pressure plate 264 .

Therefore, when the clutch pressure plate 264 is moved by the piston 271, the return spring 266 is compressed between the ring gear 240 and the clutch pressure plate 264, and when the return spring 266 is tensioned, the moved The clutch pressure plate 264 is moved in the opposite direction to return to the original position.

In addition, the master cylinder 130 is provided with a piston rod 131 in and out on one side thereof, and a port connected to the port of the cylinder part 270 and a hydraulic hose on the other side is provided.

Accordingly, when the piston rod 131 is drawn into the master cylinder 130 , the hydraulic pressure in the master cylinder 130 is supplied to the cylinder part 270 to draw out the piston 271 , and the piston rod 131 moves into the master cylinder. When it is withdrawn from 130 , as the pressure that moved the piston 271 is released, the piston 271 is drawn into the cylinder part 270 by the return spring 266 , and the hydraulic pressure in the cylinder part 270 is increased in the master cylinder 130 . ) is returned to the side.

On the other hand, the master cylinder 130 as described above is operated by being connected to the speed change motor 120 capable of forward and reverse rotation by a link means, and the link means is a screw shaft provided to rotate at one end of the speed change motor 120 ( 121) and a moving block 122 that is screwed to the screw shaft 121 to convert the rotational motion of the screw shaft 121 into a linear motion and move linearly.

And, the speed change motor 120 is provided with an encoder, that is, a position sensor 123 for detecting the rotation of the screw shaft 121 , and the piston rod 131 of the master cylinder 130 is connected to the moving block 122 . do.

Accordingly, when the shift motor 120 is driven in the forward direction, the moving block 122 is moved in a direction away from the motor body on the screw shaft 121 that rotates forward, and the screw shaft rotates in the reverse direction when the shift motor 120 is driven in the reverse direction. 121), the piston rod 131 of the master cylinder 130 is moved in a straight line while the moving block 122 is moved in a direction close to the motor body.

Accordingly, in the two-speed transmission 100 as described above, the power of the driving motor 110 is supplied by the wet multi-plate clutch 260 to the input shaft 210, the sun gear 220, the planetary gear 230, the carrier 231, and the output shaft. The first-stage driving transmitted to the wheel 140 through 250 and the power of the driving motor 110 are input shaft 210 , ring gear 240 , planetary gear 230 , carrier 231 , and output shaft 250 . ) through which the two-stage driving transmitted to the wheel 140 is possible.

The operational relationship of the two-speed gearbox for a vehicle according to the present invention as described above will be described.

First, in the first-speed driving by the two-speed transmission 100 , as shown in FIG. 7 , the clutch disk 263 and the clutch friction plate 262 are separated by the wet multi-plate clutch 260 and the ring gear 240 ), the power transmission is blocked.

In this state, the power of the driving motor 110 is directly transmitted to the input shaft 210 , and the power of the input shaft 210 is the sun gear 220 , the planetary gear 230 , and the carrier 231 as shown in the left drawing of FIG. 7 . ) is transmitted to the output shaft 250 , and the power transmitted to the output shaft 250 is output in a reduced state through the reduction gear 253 to rotate the wheel 140 under reduced speed.

At this time, the power of the driving motor 110 is equally transmitted to the clutch housing 261 through the input shaft 210 , but the power transmitted to the clutch housing 261 is separated from the clutch disk 263 and the clutch friction plate 262 . Therefore, it is not transmitted to the ring gear 240 and is in a blocked state.

On the other hand, as the planetary gear 230 rotates between the sun gear 220 and the ring gear 240 and revolves along the outer periphery of the sun gear 220, as shown in the lower right graph of FIG. 7 , the ring gear 240 is It does not rotate and remains stationary. And the carrier 231 is rotated in the same direction as the orbital direction of the planetary gear 230 .

After that, when shifting from 1st gear to 2nd gear, as shown in the left drawing of FIG. 8 , the piston 271 of the cylinder part 270 is drawn out by the master cylinder 130 and the clutch pressure plate 264 is pushed and transferred. do.

Then, with the clutch pressure plate 264 in contact with the clutch disk 263 , the clutch disk 263 is moved from the outer periphery of the ring gear 240 toward the clutch friction plate 262 , and the moving clutch disk 263 rotates. It is moved and brought into contact with the clutch friction plate 262 that becomes a slip until it comes into close contact.

And, when the clutch disk 263 is in close contact with the rotating clutch friction plate 262, the clutch disk 263 is rotated integrally with the clutch friction plate 262, and thus the one-way clutch 241 of the ring gear 240 is As the ring gear 240 is released and starts to rotate in the same forward direction as the sun gear 220 , it can be seen that the rotation speed of the ring gear 240 is gradually increased as shown in the lower right graph of FIG. 8 .

In addition, the rotational speed of the planetary gear 230 revolving along the outer periphery of the sun gear 220 due to the planetary gear ratio along with the slip phenomenon of the clutch disk 263 and the clutch friction plate 262 generated in the shift process is gradually reduced. .

Accordingly, although slip torque is generated between the clutch disk 263 and the clutch friction plate 262 in the shift process as described above, the sense of power cut due to the torque cut off is completely prevented, so that stable power transmission is possible.

Thereafter, after the two-speed shift, the rotation of the planetary gear 230 is completely stopped and only the revolution is maintained.

After shifting to the second gear in this way, as shown in the left diagram of FIG. 9 , the power of the input shaft 210 is applied to the ring gear 240 , the planetary gear 230 , and the carrier 231 by the wet multi-plate clutch 260 . It is transmitted to the output shaft 250 through the output to the wheel 140 .

Therefore, after shifting to the second gear, the power of the input shaft 210 is transferred to the sun gear 220 and the ring gear 240 as it is, and the sun gear 220 and the ring gear 240 rotate at the same speed and direction. The gear 230 has only an orbit moving along the outer periphery of the sun gear 220 in a state in which rotation is stopped, and the ring gear 240 has the same speed as the sun gear 220 as shown in the lower right graph of FIG. 9 . As it rotates, its power is transmitted to the output shaft 250 through the carrier 231 by the revolution of the planetary gear 230 , so that the wheel 140 rotates faster than the first stage.

And, in a state in which power is transmitted by the wet multi-plate clutch 260 as described above, reverse rotation of the driving motor 110 , that is, backward power can be transmitted.

That is, the reverse power due to the reverse rotation of the driving motor 110 is transmitted to the input shaft 210 as it is, and the reverse power of the input shaft 210 is the sun gear 220 and the ring gear 240 by the wet multi-plate clutch 260 . In this case, the ring gear 240 is provided in a fixed state because reverse rotation is prevented by the one-way clutch 241 .

Accordingly, the reverse power of the input shaft 210 is output only through the sun gear 220 , and the planetary gear 230 rotates with the revolution between the reversely rotating sun gear 220 and the fixed ring gear 240 .

At this time, the planet gear 230 is rotated in the opposite direction to the sun gear 220, and the orbital direction is rotated in the same direction as the sun gear 220, so that the carrier 231 is rotated in the same direction as the orbital direction of the planetary gear 230. As a result, the backward power of the input shaft 210 is output to the wheel 140 through the output shaft 250 to enable backward movement.

On the other hand, the reverse power as described above is impossible to transmit power in the first mode of the two-speed transmission 100 .

That is, the reverse power of the input shaft 210 is blocked to the ring gear 240 by the wet multi-plate clutch 260 whose connection is blocked, and is transmitted only to the sun gear 220 so that the sun gear 220 and the planetary gear 230 are 1 It rotates (rotates) in the opposite direction to the single and double mode.

At this time, the carrier 231 must be rotated in the same reverse direction as the sun gear 220, and a forward rotational force is applied to the ring gear 240 in a stationary state by the reverse rotation (rotation) of the planetary gear 230, Accordingly, the ring gear 240 is rotatable in the forward direction.

Therefore, as the carrier 231 and the ring gear 240 rotate in opposite directions, the planet gear 230 does not revolve but rotates in place (rotation) only, so that the carrier 231 is in a stationary state. It is impossible to transmit reverse power to the wheel 140 .

Although the present invention has been described in detail through specific examples, this is intended to describe the present invention in detail, and the present invention is not limited thereto, and by those of ordinary skill in the art within the technical spirit of the present invention. It is clear that the modification or improvement is possible.

All simple modifications and variations of the present invention fall within the scope of the present invention, and the specific protection scope of the present invention will be clarified by the appended claims.

100: two-speed transmission 110: drive motor
111: speed sensor 120: variable speed motor
121: screw shaft 122: moving block
123: position sensor 130: master cylinder
131: piston rod 140: wheel
150: controller 200: transmission housing
210: input shaft 211: input end bearing
220: sun gear 230: planetary gear
231: carrier 240: ring gear
241: one-way clutch 242: stopper
250: output shaft 251: output stage bearing
252: output speed sensor 253: reduction gear
260: wet clutch 261: clutch housing
262: clutch disk 263: clutch friction plate
264: clutch pressure plate 265: release bearing
266: return spring 270: cylinder part
271: piston 272: hydraulic sensor

Claims (6)

an input shaft connected to a driving motor capable of forward and reverse rotation;
a sun gear provided to rotate with the input shaft;
a plurality of planetary gears meshed with the outer periphery of the sun gear;
a carrier connecting the plurality of planetary gears in a rotatable state, respectively;
a ring gear having a planetary gear meshed with its inner periphery;
a one-way clutch provided on the ring gear to rotate the ring gear only in the forward direction;
a clutch connected to the input shaft to transmit or block rotational power of the input shaft to the ring gear;
Including; including;
One-stage driving in which the power of the drive motor is transmitted to the wheel through the input shaft, sun gear, planetary gear, carrier, and output shaft by the clutch, and the power of the drive motor is transmitted to the wheel through the input shaft, ring gear, planetary gear, carrier, and output shaft To enable two-speed driving,
The clutch includes a clutch housing connected to the input shaft and rotating together with the input shaft;
a clutch friction plate provided to rotate like the clutch housing on the inner periphery of the clutch housing;
a clutch disk provided to rotate like the ring gear on the outer periphery of the ring gear and selectively in contact with the clutch friction plate to transmit or block power to the ring gear;
The clutch disk is provided with a clutch pressure plate that rotates like the clutch disk and moves the clutch disk,
A return spring is provided between the clutch pressure plate and the ring gear to return the moved clutch pressure plate to its original position.
The ring gear is provided with a stopper for stopping the movement of the clutch pressure plate,
The clutch pressure plate is provided with a cylinder part having a piston connected through a release bearing to move the clutch pressure plate,
A master cylinder for moving the piston by supplying hydraulic pressure is connected to the cylinder part and is provided.
The master cylinder is a two-speed gearbox that is provided to be operated by a shift motor capable of forward and reverse rotation.
The method according to claim 1,
The clutch disk is spline-coupled to the outer periphery of the ring gear and moved in the axial direction to contact or separate the clutch friction plate.
The method according to claim 1,
The variable speed motor includes a screw shaft provided to rotate at one end thereof, and a moving block coupled to the screw shaft to convert the rotational motion of the screw shaft into a linear motion,
The moving block is connected to a piston rod provided in the master cylinder to move the piston rod in a straight line in the master cylinder. delete delete delete

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