KR20120088934A - Multi stage automatic transmission for a vehicle - Google Patents

Abstract

PURPOSE: An active type automatic transmission is provided to reduce fuel consumption by possessively changing speed through input rate difference and to improve power transmission efficiency. CONSTITUTION: A housing(110) forms an outer tube. An input unit(120) comprises a plurality of input gears. The plurality of input gears is combined with the outer circumference of an input shaft as a pyramid shape. An output unit(150) comprises a plurality of cam gears in which a cam groove is formed in inside. A friction member(180) is selectively rubbed in the inner wall of the cam groove. A presser unit(190) pressurizes the friction member to the radial direction outer side. A fluid pump provides fluid pressure which is pressurizing power of the presser unit by being formed inside the housing.

Description

Active automatic transmission {MULTI STAGE AUTOMATIC TRANSMISSION FOR A VEHICLE}

The present invention relates to an active automatic transmission, and more particularly, the shift can be made actively by the input speed difference without a separate control for shifting, so that the power transmission efficiency can be improved as well as increasing the power performance. Rather, it relates to an active automatic transmission that can reduce fuel consumption.

BACKGROUND OF THE INVENTION [0002] The multi-speed gear mechanism of an automatic transmission applied to a vehicle or the like usually consists of a combination of a plurality of planetary gear sets.

A gear train in which a plurality of planetary gear sets are combined performs a function of shifting a multi-step gear to an output side when rotation power is input from a torque converter that converts and transmits engine torque.

The power train of such an automatic transmission is known to be advantageous in terms of power performance and fuel consumption rate as the more gear stages are retained. Therefore, the research on the gear train that can realize more shift stages continues.

However, even if the same shift stage is implemented, the durability, power transmission efficiency, size, and weight vary greatly depending on the combination method of the planetary gear set. Therefore, the development of a gear train that is more robust and compact while minimizing power loss can be achieved. Efforts are ongoing.

Currently, the development direction of the gear train using the planetary gear set is how to combine the existing single pinion planetary gear set and the double pinion planetary gear set, and how to put the clutches, brakes, and one-way clutch in any position The focus is on whether the dog can be deployed to achieve the desired speed and hence the transmission ratio without any possible power loss.

On the other hand, in the case of the manual transmission, too many shift stages may cause inconvenience that the driver must shift frequently.

However, in the case of an automatic transmission, the computer transmission control unit (CJU) automatically controls the operation of the gear train in accordance with the driving state to perform the shift. Therefore, developing a gear train that can realize more shift stages is possible. It is a very important value.

In order to respond to this trend, various studies have been conducted, and recently, a gear train of an automatic transmission that can realize a shift stage of 6 forward speed and 8 forward speed has also been proposed.

Accordingly, the present applicant can easily perform a shift stage of eight forward speeds, or higher and lower, and of course, the operation between the shift stages can be harmoniously operated by an organic mechanism, thereby improving power transmission efficiency and shifting feeling than before. The Korean Patent Office has filed a number of new types of multi-speed automatic transmissions for automobiles that can increase the power performance and reduce fuel consumption.

Previously applied technologies implement multiple shifts with a series of mechanisms that apply multiple pressure chambers or a single pressure chamber and control the flow of hydraulic pressure.

However, if the shift can be made actively by the input speed difference without any separate control for the shift, the power transmission efficiency can be improved, so it is expected to reduce the fuel consumption rate while improving the power performance. Is required.

It is an object of the present invention that active shifting can be made by the input speed difference without any separate control for shifting, so that the power transmission efficiency can be improved, as well as active power that can reduce fuel consumption while increasing power performance. To provide a transmission.

The object is a housing forming an appearance; An input unit having an input shaft and a plurality of input gears coupled to an outer circumferential surface of the input shaft in a pyramid shape; An output part having an output shaft and a plurality of cam gears arranged in a reverse pyramid shape on an outer circumferential surface of the output shaft and engaged with the input gears and having cam grooves formed therein; A plurality of friction members disposed in cam grooves of the cam gears, respectively, for selectively stopping friction and sliding friction on an inner wall of the cam groove; And a pressing unit for pressing the friction members radially outward so that the output shaft can be rotated while any one selected from the plurality of cam gears is operated according to the input speed difference of the input unit. Is achieved by the transmission.

Here, the pressing unit, the hydraulic pump is provided in the housing for providing a hydraulic pressure of the pressing power of the pressing unit; A plurality of hydraulic communication paths communicating a single pressure chamber formed in the output shaft with the corresponding friction members; Pistons respectively provided in the plurality of hydraulic communication paths, for urging the friction member radially outward at a corresponding position; And a cylinder in which the piston is reciprocally received.

Hydraulic pressure from the hydraulic pump may be uniformly provided through the plurality of hydraulic communication paths.

Among the plurality of cam gears, the cam gear of the highest speed may have a larger width than the cam gear of the other low speed gears.

An inner wall of the cam groove may further include at least one protrusion projecting toward the radially inner side or a groove portion recessed toward the radially outer side.

The input shaft and the plurality of input gears may be assembled together by a one-way clutch.

The pressing unit may include: a friction member moving passage part provided in each of the cam gears to form a space in which the friction member is moved; And a spring disposed in the friction member moving passage part to selectively press the friction member radially outward at a corresponding position.

The friction member moving passage part may be arranged in plural at equal angle intervals along the circumferential direction of the cam gear.

In the case of the cam gear of the highest speed or the reverse gear of the plurality of cam gears, the hydraulic pressure may be applied as a power source for selectively pressing the friction member radially outward.

According to the present invention, the shift can be made actively by the input speed difference without a separate control for shifting, so that the power transmission efficiency can be improved and the power consumption can be increased, but the fuel consumption rate can be reduced. .

1 is a schematic structural diagram of an active automatic transmission according to an embodiment of the present invention;
2 is a plan view of main parts of the output unit of FIG.
3 is a perspective view of an arrangement state between an input gear and a cam gear shown in FIG. 1;
4 is an internal structural view of the cam gear of the first to sixth stage shown in FIG.
5 is an internal structural view of the seventh gear of the cam gear shown in FIG.
6 is a schematic structural diagram of an active automatic transmission according to another embodiment of the present invention;
7 is a plan view of the cam gear shown in FIG.
8 and 9 are modified examples of FIG. 7, respectively.

Hereinafter, with reference to the accompanying drawings will be described a preferred embodiment of the present invention.

1 is a schematic structural diagram of an active automatic transmission according to an embodiment of the present invention, Figure 2 is a plan view of the main portion of the output of Figure 1, Figure 3 is a perspective view of the arrangement state between the input gear and the cam gear shown in FIG. 4 is an internal configuration diagram of the first to sixth cam gears shown in FIG. 1, and FIG. 5 is an internal configuration diagram of the seventh cam gear shown in FIG.

As shown in these figures, the active automatic transmission of the present embodiment is to enable the shift is actively made by the input speed difference without a separate control for the shift.

In other words, in the active automatic transmission of this embodiment, the shift is automatically generated by the input speed difference while the hydraulic pressure is constantly applied.

In the present embodiment, the transmission of the reverse 1 and forward 7 gears is shown, but this is only one embodiment, it is not necessary to limit the scope of the present invention in the shape of the drawings.

1 to 3, the active automatic transmission of the present embodiment includes a housing 110, an input unit 120, an output unit 150, a friction member 180, and a pressing unit 190.

The housing 110 forms the appearance of the active automatic transmission of this embodiment. Since the input unit 120 and the output unit 150 have a substantially pyramid shape, the appearance of the housing 110 may be determined correspondingly.

Of course, the appearance of the housing 110 may have a shape different from those of FIGS. 1 and 2 in consideration of the relationship with the transmission peripheral device.

The input unit 120 has an input shaft 130 and a plurality of input gears 140a to 140c coupled to the outer circumferential surface of the input shaft 130 in a pyramid shape. Since the transmission of this embodiment has one reverse gear and seven forward gears, the total number of input gears 140a to 140c is eight.

The input shaft 130 and the plurality of input gears 140a-140c are assembled to each other by the one-way clutch 125. Thus, the input shaft 130 does not rotate in the reverse direction. Of course, since the scope of the present invention does not need to be limited thereto, it is possible even if the one-way clutch 125 is not.

The output unit 150 has an output shaft 160 and a plurality of cam gears 170a-170c arranged on the outer circumferential surface of the output shaft 160 in an inverse pyramid shape.

Eight cam gears 170a? C are also provided and interact with the eight input gears 140a? C. Reference numeral 170a denotes a single-stage 6-speed cam gear, 170b is a seven-speed cam gear that is the highest stage, and 170c is a cam gear of the reverse stage.

Cam grooves 171a, 171b, 171b ', and 171c are formed in the cam gears 170a to 170c. The shape of the cam groove may vary from that shown.

On the other hand, the cam gear 170b of the seventh speed, which is the highest speed among the plurality of cam gears 170a to 170c, has a larger width than the cam gears 170a of the first to sixth speeds, which are the remaining low speed ends. This is because the output from the cam gear 170b side of the seventh stage is large.

This is explained further. In the case of FIG. 4, the cam gears 170a of the first to sixth stages are formed. The cam grooves 171a formed in the cam gears 170a are provided with grooves G recessed outward in the radial direction. .

In this case, when the friction member 180 is caught in the groove portion G as shown in FIG. 4A, the cam gear 170a can be rotated, and the remaining position is slipped as shown in FIG. 4B. Of course, you may form the protrusion (not shown) which protrudes toward the center of the cam gear 170a instead of the groove part G. As shown in FIG.

On the contrary, in the case of FIG. 5, the cam gear 170b of the seventh stage is the highest stage, and the inside of the cam gear 170b has cam grooves 171b and 171b different in eccentricity as in FIGS. 5A and 5B. ') Is formed. At this time, the phase difference between the two sides is 180 degrees, and the torque can be maintained largely because the internal output shaft 160 can be bitten by the cam grooves 171b and 171b 'in a wide area of its circumferential surface or can be frictionally reversed. have.

The reason that the phase difference on both sides is 180 degrees is that when the overload torque is transmitted to the cam gear 170b, the overload torque is not transmitted to the input gear 140b corresponding to the cam gear 170b, that is, slip occurs when overload torque is generated. This is to ensure that a phenomenon is generated so that only a certain number of revolutions (rpm) can be delivered.

The friction member 180 is disposed in the cam grooves 171a, 171b, 171b ', and 171c of the cam gears 170a to 170c, respectively, and selectively rubs against the inner walls of the cam grooves 171a, 171b, 171b' and 171c. That is, the friction member 180 may be in close contact with the inner walls of the cam grooves 171a, 171b, 171b 'and 171c to rotate the cam gears 170a to 170c, and the friction member 180 may be the cam grooves 171a, 171b, It may slip on the inner walls of 171b 'and 171c. In the latter case, the cam gears 170a to 170c do not rotate.

The pressing unit 190 radially rotates the friction members 180 to rotate the output shaft 160 while any one selected from the cam gears 170a to 170c is operated according to the input speed difference of the input unit 120. It acts to press outward. In this embodiment, the pressing power of the pressing unit 190 is hydraulic pressure.

The pressing unit 190 is provided in the housing 110, the hydraulic pump 191 for providing the hydraulic pressure that is the pressing power of the pressing unit 190, and a single pressure chamber 161 formed inside the output shaft 160. ) And a plurality of hydraulic communication paths 192 for communicating the plurality of friction members 180 with corresponding ones, and are provided in the plurality of hydraulic communication paths 192, respectively, and radially outwards the friction member 180 at a corresponding position. And a piston 193 for selectively pressing the cylinder 193 and a cylinder 194 in which the piston 193 is reciprocally received.

At this time, the hydraulic pressure from the hydraulic pump 191 is uniformly provided through a plurality of hydraulic communication path (192). In other words, the pressure applied to the piston 193 is also the same since the magnitudes of the hydraulic pressures applied to the plurality of hydraulic communication paths 192 are all the same.

Referring to FIGS. 1 and 2, the seventh stage, which is the highest speed, uses a large diameter cylinder, and the lower speed stage uses a small diameter cylinder. In this case, even if the same pressure acts on the hydraulic communication path 192, the fastest speed is used. The friction coefficient will be large and the remaining low speed can be kept small.

For reference, the reverse illustrated in FIGS. 1 and 2 has a separate independent flow passage 198, so that pressure is supplied only to the reverse by the lever operation provided in the driver's seat, and the like. The highest speed acts like the torque converter of an automatic transmission. If the frictional force is higher than the driving force, the friction sliding turns. If the frictional force is lower than the driving force, the frictional rotation rotates.

With this configuration, if the hydraulic pressure is constantly applied, if the seventh stage on the input unit 120 side is over the prescribed speed, that is, overtorque is applied, the seventh cam gear 170b on the output unit 150 side is slipped ( slip) occurs.

As a result, power is transmitted to the sixth stage on the input unit 120 side, and as a result, the sixth stage cam gear 170a on the output unit 150 side is rotated and output through the output shaft 160.

The reason why slip occurs at the output seventh stage when over torque is applied at the seventh stage of the input side is that the static friction acts between the contact surfaces of the cam grooves 171b and 171b 'of the output seventh-stage cam gear 170b and the friction member 180. As the torque transmitted to the output shaft 160 increases as compared to the moment, sliding friction occurs between the cam grooves 171b and 171b 'of the output side seventh cam gear 170b and the friction member 180. Thus, the output side seventh cam gear 170b slips with respect to the output shaft 160. On the other hand, the radius in which the cam groove 170a of the output six-speed cam gear 170a and the friction member 180 contact each other from the center of the output shaft 160 is the cam grooves 171b and 171b 'of the output seven-speed cam gear 170b. And the friction member 180 is larger than the radius of contact, so that the output shaft 160 as compared to the static friction moment acting between the cam groove 171a of the output six-stage cam gear 170a and the contact surface of the friction member 180. The torque transmitted is small so that the cam groove 171a of the output six-speed cam gear 170a and the friction member 180 stop friction, and the power of the input unit 120 is output through the six-speed input gear 140a. It is transmitted to the output shaft 160 via the friction member 180 accommodated in the six-speed cam gear 170a and the output six-speed cam gear 170a. As a result, it can be seen that the shift is automatically generated by the input speed difference while the hydraulic pressure is constantly applied.

It demonstrates more concretely.

When the accelerator pedal is depressed at the start, a solenoid valve (not shown) is opened by a signal to the accelerator pedal, and the oil pressure from the hydraulic pump 191 is applied to the piston 193 so that the piston 193 pushes the friction member 180. In contact with the cam gear (170a, 170b) is loaded at the highest speed to rotate. At this time, when the traction force is lowered to the traction force, the sliding friction rotation occurs between the cam gear (170a, 170b) and the friction member 180. This will put a load on the sixth stage. At this time, if the traction force is applied, the load is established at the fifth stage. If the traction force is applied to the fifth stage, the fourth stage is loaded. Continuously by the traction force, the shift is made at the stage corresponding to the driving force and the traction force. When the towing force is restored, shifting is performed at the optimum gear stage while actively moving toward the high gear stage.

The mechanism of active shifting is as follows.

The maximum driving force is input in the seventh speed. In other words, the inner circumferential surfaces of the cam gears 170a and 170b and the friction member 180 are by hydraulic pressure (or spring elastic force) capable of maintaining a friction force corresponding thereto. In the low-speed movement, when the traction force is reduced, the friction member 180 is pushed down when the traction force is reduced, and the inner and outer surfaces of the cam gears 170a and 170b and the friction member 180 are slid frictionally rotated in the static friction state, and thus the output side and the input side. The circumferential difference of and the load is applied at the low speed stage idling the one-way clutch 125. When the frictional sliding in the high speed stage, the load is applied in the next low speed stage, and when the traction is restored, the shift is made to the high speed stage without any manipulation.

For example, when the load is rotated at the fourth stage, the seventh, sixth, and fifth stages are sliding frictional rotation, the fourth stage is a static frictional rotation, and the third, second, and first stages are idling by the one-way clutch.

When the driving is smooth in the accompanying driving, the traction is restored. The drive wheel moves to the seventh stage where the maximum traction is input. Since there is a mechanism to always move to the high stage even if the static friction load rotates in the fourth stage, shifting to the high stage is actively made when the traction force is restored. When shifting in the 4th stage, the drive wheels of the 7th stage maintain the rotational force of the maximum traction force, the 6th stage also maintains the slight rotational force, and the 5th stage also maintains the weak rotational force by the sliding frictional rotation. It exists.

In other words, when the pedal is pressed by the accelerator pedal sensor, the pressure is applied by the solenoid valve (not shown) and the load is applied from the highest speed. Depending on the driving conditions, when the traction force is reduced, shift to the lower speed. When the traction force is restored, the shift is actively performed without the need for shift operation or T.C.U or E.C.C control.

When the pedal is released, the pressure is zeroed by the accelerator pedal sensor and the solenoid valve to be neutral.

The output shaft 160 has torque as much as the frictional force, whether in the stationary state or the rotational state, but the low end is continuously affected by the high end friction.

As such, according to the present embodiment, the shift can be actively performed by the input speed difference without any separate control for the shift, thereby improving the power transmission efficiency as well as reducing the fuel consumption rate while increasing the power performance. Will be.

6 is a schematic structural diagram of an active automatic transmission according to another embodiment of the present invention, Figure 7 is a plan view of the cam gear shown in FIG.

While the above-described embodiment drives the whole hydraulically, the embodiment of FIG. 6 drives the whole by the elastic force of the spring 293.

The active automatic transmission shown in FIG. 6 also includes a housing 210, an input unit 220, an output unit 250, a friction member 280, and a pressing unit 290.

The input unit 220 has an input shaft 230 and a plurality of input gears 240 coupled to the outer circumferential surface of the input shaft 230 in a pyramid shape. The input shaft 230 and the plurality of input gears 240 are assembled to each other by the one-way clutch 225.

In addition, the output unit 250 includes an output shaft 260 and a plurality of cam gears 270 arranged in an inverse pyramid shape on an outer circumferential surface of the output shaft 260.

On the other hand, in the case of Figure 6, the pressing portion 290, the friction member moving passage portion 291 and the friction member moving passage that is provided in the cam gear 270, respectively, to form a space for the friction member 280 is moved, A spring 293 is disposed in the portion 291 to selectively press the friction member 280 radially outward at the position.

In this case, a plurality of friction member moving passages 291 may be arranged at equal angle intervals along the circumferential direction of the cam gear 270.

As shown in FIG. 7, the cam groove 271 is provided inside the cam gear 270, and the cam groove 271 is provided with the protrusion T1 protruding inward in the radial direction. In this embodiment, the protrusion The case of two (T1) is illustrated.

In this case, the friction member 280 and the spring 293 may also be provided to correspond to the number of the projections (T1), the friction member 280 is sliding friction between the projections (T1) or constrained by the projections (T1). And rotate with the cam gear 270 to transmit power.

With this configuration, if the pressure by the springs 293 is constantly applied, the seven-stage cam on the output unit 250 side if the initial speed is over the specified speed at the seventh stage on the side of the input unit 220, that is, the overtorque is applied. As described above in the gear 270, slip is generated.

As a result, power is transmitted to the sixth stage on the input unit 220 side, and as a result, the sixth stage cam gear 270 on the output unit 250 side is rotated and output through the output shaft 260.

The operation of this embodiment will be briefly described.

The maximum traction force of the drive wheel is input to the spring 293 side of the highest speed, and the remaining low speed inputs the spring 293 lower than the highest speed. When power is transmitted to the input side, the input side and the output side are engaged to rotate. When operated hydraulically as shown in Figs. 1 and 2, when the pressure is zero (zero) it is in a neutral state. The input side is rotated normally and the output side is in the neutral state by the cam gear 270 is idling.

When the traction force is lowered at the start, the friction member 280 exceeds the protrusions T1 to T3 of the output side cam gear 270 to the pressure (frictional force) traction force at the highest speed, and the friction sliding is performed. Therefore, the load is applied to the next stage idling by the input side one-way clutch 225. If the traction force is lowered in the next stage, the friction member 280 is over the projection (T1 ~ T3, see Figs. 7 to 9) of the output side cam gear 270 and the load is applied to the next low-speed end. Continuously and actively shifting to the lower end until the traction force is won. When the friction coefficient due to pressure is applied to the traction force, the gear shifts continuously and actively shifts at the optimum continuous stage. When traction is restored, shifting is actively performed.

Since the hydraulic pressure of the maximum driving force is input to the driving wheel at the highest speed, the torque of the maximum driving force of the driving wheel is maintained on the output shaft 260 by friction sliding. The other stages also have less torque, so the force continues to move from the low end to the high end.

As the towing force is restored, the shift is made at a gear stage that is actively adapted to the driving force and the towing force. Due to the torque of the highest speed stage maintained and the input and output gear ratios of the low speed stage, the low speed stage is loaded even with a weak frictional force (hydraulic). The gear shift stage is multistage, but the actual shifting process is carried out continuously.

8 and 9 are modified examples of FIG. 7, respectively.

Cam grooves 371 and 471 provided in the cam gears 370 and 470 shown in these figures are provided with protrusions T2 and T3 protruding inward in the radial direction. In the case of FIG. 8, four protrusions T2 are provided. In the case of FIG. 9, the case where there is one projection part T3 is shown.

In this case, the friction members 380 and 480 and the springs 393 and 493 may also be provided to correspond to the number of the projections T2 and T3, and the friction members 380 and 480 are slid friction between the projections T2 and T3 or the projections T2. It is constrained by T3 and rotates with the cam gears 370 and 470 to transmit power.

Although the present embodiment has been described in detail with reference to the drawings, the scope of the present invention is not limited to the above-described drawings and descriptions.

1 and 2 is a case in which the hydraulic pressure is applied alone, in the case of Figure 6 the elastic force of the spring is applied alone or they may be applied in combination. For example, the top end may be applied hydraulically, and the remaining low end may be applied by the spring force.

On the other hand, in the case of the present embodiment, since the shift is actively progressed, it can be used for various purposes. For example, it can be widely used for two-wheeled vehicles, ships, and various industrial uses.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Accordingly, such modifications or variations are intended to fall within the scope of the appended claims.

110 housing 120 input unit
150: output unit 180: friction member
190: pressurization unit 191: hydraulic pump
192: hydraulic communication path 193: piston
194: cylinder

Claims (9)

A housing defining an appearance;
An input unit having an input shaft and a plurality of input gears coupled to an outer circumferential surface of the input shaft in a pyramid shape;
An output part having an output shaft and a plurality of cam gears arranged in a reverse pyramid shape on an outer circumferential surface of the output shaft and engaged with the input gears and having cam grooves formed therein;
A plurality of friction members disposed in cam grooves of the cam gears, respectively, for selectively stopping friction and sliding friction on an inner wall of the cam groove; And
And an urging unit for urging the friction members radially outward so that the output shaft can be rotated while any one selected from the plurality of cam gears is operated according to an input speed difference of the input unit. . The method of claim 1,
The pressing portion
A hydraulic pump provided in the housing to provide hydraulic pressure which is a pressurizing power of the pressing unit;
A plurality of hydraulic communication paths communicating a single pressure chamber formed in the output shaft with the corresponding friction members;
Pistons respectively provided in the plurality of hydraulic communication paths, for urging the friction member radially outward at a corresponding position; And
And a cylinder in which the piston is reciprocally received. The method of claim 2,
The hydraulic pressure from the hydraulic pump is uniformly provided through the plurality of hydraulic communication paths. The method of claim 1,
Among the plurality of cam gears, the highest speed cam gear is an active automatic transmission, characterized in that the tooth width is formed larger than the cam gear of the remaining low speed stage. The method of claim 1,
The inner wall of the cam groove is an active automatic transmission, characterized in that further formed at least one projection projecting toward the radially inward or recessed toward the radially outer side. The method of claim 1,
And said input shaft and said plurality of input gears are assembled together by a one-way clutch. The method of claim 1,
The pressing portion
A friction member moving passage part provided in each of the cam gears to form a space in which the friction member is moved; And
And a spring disposed in the friction member moving passage part to selectively pressurize the friction member radially outward at a corresponding position. The method of claim 7, wherein
And the friction member moving passage part is arranged in plural at equal angle intervals along the circumferential direction of the cam gear. The method of claim 7, wherein
In the case of the cam gear of the highest speed or the reverse gear of the plurality of cam gears, the hydraulic automatic transmission is applied as a power source for selectively pressing the friction member radially outward.

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