JP2002349700A - Shift-by-wire system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve ease of loading a shift actuator in a vehicle by reducing its size, while securing its torque capacity, and also provide a shift-by-wire system that can precisely shift to a target range position. SOLUTION: In the shift-by-wire system, a shift actuator 30 has a construction comprising a planetary gear mechanism 33, having a sun gear 39, a pinion carrier 42 and a ring gear 41, a drive means coupled with at least one of the sun gear 39 and the ring gear 41, and an actuator output shaft 36 coupled with the pinion carrier 42.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention belongs to the technical field of a shift-by-wire system in which a shift range of an automatic transmission is selected by driving a motor based on electric control.

[0002]

2. Description of the Related Art Conventionally, as a shift-by-wire system, for example, one described in Japanese Utility Model Laid-Open No. 7-16067 is known. In the shift-by-wire system described in this publication, a gear mechanism is driven by a motor driven based on electric control, and a range switching valve of the automatic transmission is switched. FIG. 10 is a schematic view of a gear mechanism according to the related art. First, the configuration will be described. 101 is a sun gear, 102 is a pinion gear, 103 is a ring gear,
4 is a first worm wheel, 105 is a second worm wheel, 106 is an electromagnetic clutch, 108 is a first motor, 1
Reference numeral 09 denotes a second motor, 111 denotes a rotating member, 112 denotes an input shaft, and 113 denotes an output gear. (At the time of driving the first motor) When the driving force of the first motor 108 is input, since the second motor 109 is fixed, the second worm wheel 105 meshing with the second worm 109a is fixed, so that the pinion carrier 105a is also Fixed. The first worm 10 is driven by the first motor 108.
The first worm wheel 104 is driven from 8a. At this time, the electromagnetic clutch 106 is engaged, and the first worm wheel 104 and the rotating member 111 rotate integrally. This rotational driving force is transmitted to the sun gear 101 via the input shaft 112.
, The ring gear 103 is driven to rotate via the pinion gear 102, and the output gear 113 is driven via the output member 103 a connected to the ring gear 103, thereby switching the range. (Driving the second motor) When the driving force of the second motor 109 is input, the electromagnetic clutch 106 is engaged. Since the first motor 108 is fixed, the first worm wheel 104 meshing with the first worm 108a is fixed, and thus the input shaft 112 is also fixed, so that the sun gear 101
Is fixed. The driving of the second motor 109 drives the second worm wheel 105 from the second worm 109a. The second worm wheel 105 and the pinion carrier 105a rotate integrally. This rotational driving force rotationally drives the ring gear 103 via the pinion gear 102,
By driving the output gear 113 via the output member 103a connected to the ring gear 103, range switching is performed.

[0003]

However, the conventional shift-by-wire system has the following problems. That is, since the pinion carrier 105a is fixed and the output of the ring gear 103 is used, the size of the gear mechanism in the axial direction is increased by the size of the pinion carrier 105a and the output member 103a.

FIG. 11 is a collinear diagram when the first and second motors of the prior art are driven. As shown in the alignment chart (a), when the first motor is driven and the second motor is stopped, the rotation input to the sun gear 101 is reduced and the ring gear 1 is rotated.
Since the output is performed from 03, sufficient torque can be secured. However, when the first motor is stopped and the second motor is driven, the rotation input from the pinion carrier 105a is increased in speed and output from the ring gear 103, so that there is a problem that sufficient torque cannot be obtained.

[0005] This is a serious problem especially when shifting to the parking range. That is, generally, as shown in FIG. 12, the detent lever 75 is rotated by the rotation of the control shaft 36 and the parking cam 74 is operated by operating the parking rod 74, as shown in FIG.
The parking pole 72 is pushed up by the cam mechanism a,
The parking claw 72a and the parking gear 71 are configured to mesh with each other. Therefore, a strong force is applied between the parking pawl 72a and the parking gear 71, and the parking pawl 72 presses the parking cam 71a. If sufficient torque is not obtained, the parking pawl 72 is pulled out of the parking gear 71. There was a problem that it was not possible to change gears. Further, in order to obtain a sufficient torque at the time of speed increase, there is a problem that the motor becomes large and the vehicle mountability is deteriorated.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems. It is an object of the present invention to provide a shift-by-wire system in which a shift position of an automatic transmission is selected by a motor drive based on electric control. It is an object of the present invention to provide a shift-by-wire system that can improve vehicle mountability and reliably shift to a target range position by ensuring torque while reducing the size of the vehicle.

[0007]

In order to achieve the above object, according to the first aspect of the present invention, a driver is operated to output a switch signal indicating a shift position corresponding to each range such as a parking range and a drive range. A shift switch, a shift actuator provided in the automatic transmission, for driving a manual valve and a parking rod, and a shift for inputting a switch signal of the shift switch and outputting a command to obtain a shift position indicated by the switch signal to the shift actuator. And a control means, wherein the shift actuator is connected to a planetary gear mechanism having a sun gear, a pinion carrier and a ring gear, a driving means connected to at least one of a sun gear or a ring gear, and a pinion carrier. Characterized by being configured to have the actuator output shaft.

According to a second aspect of the present invention, in the shift-by-wire system according to the first aspect, the driving means of the shift actuator includes a first driving means for driving the sun gear and a second driving means for driving the ring gear. Driving means, one of the first and second driving means is a means driven by an electric motor and a worm gear, and the other means is a manual driving means which can be manually driven by a driver. It is characterized by having done.

According to a third aspect of the present invention, in the shift-by-wire system according to the first aspect, the driving means of the shift actuator includes a first driving means for driving the sun gear and a second driving means for driving the ring gear. And a driving means, wherein the first and second driving means are driven by an electric motor and a worm gear.

[0010]

In the shift-by-wire system according to the first aspect, the shift actuator includes: a planetary gear mechanism having a sun gear, a pinion carrier, and a ring gear; and driving means connected to at least one of the sun gear or the ring gear; It is composed of an actuator output shaft connected to a pinion carrier. That is, since the driving force is input from the sun gear or the ring gear and output from the pinion carrier, the input rotation can always be reduced, and a sufficient torque can be obtained. When one of the sun gear or the ring gear is fixed, the shift gear is fixed to the case of the shift actuator or the like, and the driving force is input from the other, so that only the pinion carrier 105a is provided as in the related art shown in FIG. , It is possible to downsize the gear mechanism in the axial direction,
The vehicle mountability can be improved.

In the shift-by-wire system according to the second aspect, the first means for driving the sun gear as the driving means.
Driving means and second driving means for driving the ring gear are provided. One of the first and second driving units is a unit driven by an electric motor and a worm gear, and the other is a manual driving unit that can be manually driven by a driver. For example, when the first driving means is a means driven by an electric motor and a worm gear, and the second driving means is a manual driving means, the rotation input to the sun gear is reduced and output to an actuator output shaft connected to a pinion carrier. Is done. At this time, if a failure of the electric system (such as a dead battery or a broken wire) or a failure of the electric motor occurs, the shift operation cannot be performed. At this time, since the input from the electric motor is constituted by the worm gear, it does not rotate due to the input of the driving force from the opposite side. Therefore, the sun gear is locked.

In this case, the driver operates the manual driving means to drive the ring gear. That is, for example, when such a failure occurs on a sloping ground, if the shift operation can be performed at least in the parking range, the vehicle can be reliably stopped. In addition, since a ring gear input, a sun gear fixed, and a pinion carrier output are output to the reduction side, a large force is not required at the time of manual operation by the driver.

[0013] In the shift-by-wire system according to the third aspect, the shift actuator includes first drive means for driving a sun gear and second drive means for driving a ring gear. The second drive unit is a unit that is driven by the electric motor and the worm gear. That is, both the sun gear and the ring gear can be driven by the electric motor, and when one of the driving means is stopped, the input from the electric motor is constituted by the worm gear, so that the driving force from the opposite side is reduced. No rotation due to input. Therefore, as shown in the nomographic chart of FIG. 9, even if one of the first and second driving units fails, the shift operation can be performed without any problem.

FIG. 9 shows a case where torque is particularly required.
As shown in (c), by rotating the second drive means in the reverse direction, it is possible to obtain a larger reduction ratio. For example, at the time of a shift requiring a torque such as a parking range, the pinion carrier is provided with a sufficient torque. Can be driven.

If responsiveness of the shift operation is required in a state where the torque is sufficiently secured, as shown in FIG. 9D, both the first and second driving means are rotated in the same direction. Thus, the pinion carrier can be driven with almost no deceleration, and the actuator output shaft can be driven at a high speed.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments for realizing a shift-by-wire system according to the present invention will be described below with reference to a first embodiment corresponding to claim 1 and a second embodiment corresponding to claims 1 and 2. A description will be given based on a third embodiment corresponding to claims 1 and 4.

(First Embodiment) First, the configuration will be described. FIG. 1 is an overall configuration diagram illustrating a shift-by-wire system according to a first embodiment. In the figure, 1 is an indicator showing the selected position of the shift, 2 is a fail lamp for notifying the driver of an abnormality,
Reference numeral 3 denotes an ignition switch, 4 denotes a shift switch for selecting a shift position, and 5 denotes a shift lock mechanism. Reference numeral 20 denotes a shift control unit; 63, a CVT control unit for controlling the automatic transmission 60;
, An engine control unit; 60, an automatic transmission; 61, a transmission mechanism; and 62, an inhibitor switch for outputting a range signal selected by the automatic transmission.
In this embodiment, a belt-type continuously variable transmission is mounted on the transmission mechanism 61. However, a stepped transmission can be used without any problem. Reference numeral 30 denotes a shift actuator provided near the inhibitor switch 62, and reference numeral 31 denotes a main motor.

FIG. 2 is an overall system diagram showing the shift-by-wire system of the first embodiment. The shift control unit 20 includes a main CPU 21a that calculates a drive voltage of the main motor 31 and a main driver 21 that supplies the drive voltage calculated by the main CPU 21a to the main motor 31. Also, the sub CP
U22a is provided, and the main CPU 21a and the sub CPU 22a are configured to always monitor each other and detect an abnormality. The shift control unit 20 controls the speed of the speed change mechanism 61.
A signal from the VT control unit 63 is input, and a signal is output to the engine control unit 64.

The shift actuator 30 includes a gear mechanism 33 driven by the main motor 31, a temperature sensor 35 for detecting the temperature of the main motor 31, and a gear mechanism 33.
And an angle sensor 34 for detecting a rotation angle of a control shaft 36 for controlling a shift range via an inhibitor switch 62, and is driven based on a signal from the shift control unit 20.

FIG. 3 is a sectional view of the shift actuator 30 in the first embodiment. Shift actuator 30
Is composed of a first housing 43, a second housing 44, and a third housing 45. First housing 43
The gear mechanism 33 is accommodated in the planetary accommodation room A formed between the second housing 44 and the third housing 44.
A worm 31 for inputting a driving force from the main motor 31 is provided in a worm housing chamber B formed between the housings 45.
a and the worm wheel 37 are housed.

The worm wheel 37 is connected to an input shaft 38, and the rotational driving force of the main motor 31 is transmitted to the planetary compartment A through the input shaft 38. This input shaft 38 is connected to the third housing 45.
, A ball bearing 47b provided in the second housing 44, and a ball bearing 47a provided in the pinion carrier 42 so as to be rotatable. The input shaft 38 has a hollow structure, and the angle sensor 3 is provided in the hollow.
4 and sensor rod 4 connected to pinion carrier 42
9 are provided.

A sun gear 39 provided on the inserted input shaft 38, a plurality of pinion gears 40 meshing with the sun gear 39, and the first and second housings 43 mesh with the pinion gear 40 in the planetary accommodation room A. , 44 are provided with a ring gear 41 fixedly supported. Further, a pinion carrier 42 that rotatably supports the plurality of pinion gears 40 is provided, and the pinion carrier 42 is provided with an output boss portion 42 a connected to the control shaft 36. The output boss section 42
An oil seal 46 is provided between a and the first housing 43 to make the inside of the shift actuator 30 liquid-tight. Further, the pinion carrier 42 includes a first housing 43.
Bearing 48a provided in the second housing 44
Is slidably supported via a bearing 48b provided at the bottom.

Next, the operation will be described. Main motor 31
Is transmitted from the worm 31a to the worm wheel 37 and the input shaft 38
Drive. The rotation input to the sun gear 39 provided on the input shaft 38 is output from the pinion carrier 42 to the control shaft 36 at a constant reduction ratio, and operates a shift valve (not shown).

That is, since the ring gear 41 is fixed and the output of the pinion carrier 42 is used, the size of the gear mechanism does not increase in the axial direction by the amount of the pinion carrier 105a as in the prior art. Therefore, the shift actuator 30 can be made compact, and the mountability on the vehicle can be improved.

In the first embodiment, the sun gear 39 is used. However, for example, the sun gear 39 is fixed to the second housing 44, and the main motor 31, the worm 31a, and the worm wheel 37 are formed around the ring gear 41. Is also good. Thereby, it is possible to further shorten the axial direction.

(Second Embodiment) The second embodiment is an example in which a manual shift device by a driver is added to the first embodiment. For the description of the configuration, see the first embodiment (FIGS. 1 to 3).
The description of the same points as in the above is omitted, and only different points will be described.

FIG. 4 is a longitudinal sectional view of the shift actuator 30 according to the second embodiment, and FIG.
It is C cross section. The planetary accommodation room A is provided with a manual shift device that operates via a wire 51 by operating a manual lever 50 provided in the vehicle interior. 52 is a lever member connected to the wire 51, 53 is the lever member 5
2, an operation shaft integral with the shaft 2, a substantially fan-shaped manual gear that rotates integrally with the shaft 53, 55 a lock cam, 56
Is a rock pole.

An outer gear 41 is provided around the outer periphery of the ring gear 41.
a is provided so as to mesh with the outer gear 41a only when the manual gear 54 is operated. Further, the outer circumference of the ring gear 41 and the outer gear 41a
And a lock gear 41b is provided at a position overlapping with the axial direction.
It is formed so as to mesh with the lock pole 56.

[Operation] Normally, the ring gear 41 is fixed by the lock pawl 56. Therefore, the basic operation is the same as that of the first embodiment, and the description is omitted.

If a failure of the electric system (such as a dead battery or a broken wire) or a failure of the main motor 31 occurs, the shift operation cannot be performed. At this time, since the input from the main motor 31 is constituted by the worm gear, it does not rotate due to the input of the driving force from the opposite side. Thus, the sun gear 39 is locked.

At this time, the driver operates the manual lever 50 provided in the passenger compartment. By this operation, the wire 5
Pulling 1 causes the lever member 52 to rotate, and the shaft 53 fixed to the lever member 52 to rotate. As a result, one end of the lock pawl 56 is pushed down by the rotation of the lock cam 55 provided on the shaft 53, and at the same time the lock pawl 56 comes off the lock gear 41b,
A substantially fan-shaped manual gear 54 meshes with the outer gear 41a. The manual gear 54 is configured to secure the rotation amount of the pinion carrier 42 necessary for shifting to the parking range from which range the driver stops in any selected state. For example, when such a failure occurs on a slope, the vehicle can be reliably stopped if at least a shift operation can be performed to the parking range.

As a result, the pinion carrier 42 is driven at a constant reduction ratio, and can be shifted to the parking range by manual operation. Also, the ring gear 4
Since one input, the fixed sun gear 39, and the pinion carrier 42 output are output to the deceleration side, a large force is not required when the driver operates the manual lever 50.

(Third Embodiment) The third embodiment is an example in which a sub motor 32 is added to the first embodiment. Regarding the description of the configuration, the description of the same points as in the first embodiment (FIGS. 1 to 3) will be omitted, and only different points will be described.

FIG. 6 is an overall configuration diagram showing the shift-by-wire system of the third embodiment. The difference is that a sub motor 32 is added to the shift actuator 30 in the figure.

FIG. 7 is an overall system diagram showing the shift-by-wire system of the third embodiment. The shift control unit 20 includes a main CPU 21a that calculates a drive voltage of the main motor 31 and a main driver 21 that supplies the drive voltage calculated by the main CPU 21a to the main motor 31. Further, a sub CPU 22a for calculating a drive voltage of the sub motor 32 and a sub driver 22 for supplying the drive voltage calculated by the sub CPU 22a to the sub motor 32 are provided.
The main CPU 21a and the sub CPU 22a are configured to constantly monitor each other and detect an abnormality.

The gear mechanism 3 driven by the main motor 31 or the sub motor 32 is provided on the shift actuator 30.
3, a temperature sensor that detects the temperature of the main motor 31, and an angle sensor 34 that is connected to the gear mechanism 33 and detects the rotation angle of a control shaft 36 that controls a shift range via an inhibitor switch 62. Drive is performed based on a signal from the control unit 20.

FIG. 8 is a sectional view of a shift actuator 30 according to the third embodiment. In the planetary accommodation room A, a worm 32a for inputting a driving force from the sub motor 32 and an outer worm wheel 41c provided on the outer periphery of the ring gear 41 are accommodated. When the sub-motor 32 is stopped, the input from the sub-motor 32 is constituted by the worm gear, so that it does not rotate due to the input of the driving force from the opposite side. Thus, the ring gear 41 is locked. Similarly, when the main motor 31 is stopped, the input from the main motor 31 is constituted by the worm gear, and therefore, the main motor 31 does not rotate due to the input of the driving force from the opposite side. Thus, the sun gear 39 is locked.

[Operation] FIG. 9 is an alignment chart showing the operation of the shift actuator 30 in the third embodiment. S in the figure
Represents a sun gear 39 connected to the main motor 31;
Represents a pinion carrier 42 connected to the control shaft 36, and R represents a ring gear 41 connected to the submotor 32.

As shown in FIG. 9 (a), when the main motor 31 is driven and the sub motor 32 is stopped, which is used in the normal control,
The driving force from the main motor 31 is output to the control shaft 36 at a reduction ratio X1.

As shown in FIG. 9B, when the main motor 31 is stopped and the sub motor 32 is driven due to the failure of the main motor 31, the driving force from the sub motor 32 is output to the control shaft 36 at the reduction ratio X2. Also at this time, unlike the related art, the reduction ratio can be obtained on the reduction side.

By using the main motor 31 and the sub-motor 32 in reverse rotation as shown in FIG. 9C, a larger reduction ratio X3 can be obtained. This is effective when a large torque is required, for example, when shifting to the parking range or when shifting from the parking range.

As shown in FIG. 9D, by using both the main motor 31 and the sub motor 32 in the same rotational drive, a small reduction ratio X4 can be obtained. This allows the control shaft 36 to be driven more quickly during a shift that requires responsiveness without requiring torque.

(Other Embodiments) The shift-by-wire system of the present invention has been described based on the first, second and third embodiments.
The present invention is not limited to these embodiments, and changes and additions of the design are allowed without departing from the gist of the present invention described in each claim of the claims.

[Brief description of the drawings]

FIG. 1 is an overall system diagram showing a shift-by-wire system according to a first embodiment.

FIG. 2 is a control system diagram of the shift-by-wire system of the first embodiment.

FIG. 3 is a sectional view of a shift actuator in the shift-by-wire system of the first embodiment.

FIG. 4 is a sectional view of a shift actuator in a shift-by-wire system according to a second embodiment.

FIG. 5 is a sectional view of the shift actuator taken along line CC in the shift-by-wire system according to the second embodiment.

FIG. 6 is an overall system diagram showing a shift-by-wire system according to a third embodiment.

FIG. 7 is a control system diagram of a shift-by-wire system according to a third embodiment.

FIG. 8 is a sectional view of a shift actuator in a shift-by-wire system according to a third embodiment.

FIG. 9 is an alignment chart of planetary gears in the shift-by-wire system of the third embodiment.

FIG. 10 is a schematic view of a shift actuator in a conventional shift-by-wire system.

FIG. 11 is an alignment chart of a planetary gear in a conventional shift-by-wire system.

FIG. 12 is a perspective view illustrating a detent mechanism and a parking mechanism according to the present application and the related art.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Indicator 2 Fail lamp 3 Ignition switch 4 Shift switch 5 Shift lock mechanism 20 Shift control unit 21 Main driver 21a Main CPU 22 Sub driver 22a Sub CPU 30 Shift actuator 31 Main motor 31a Worm 32 Sub motor 32a Worm 33 Gear mechanism 34 Angle sensor 35 Temperature sensor 36 Control shaft 37 Worm wheel 38 Input shaft 39 Sun gear 40 Pinion gear 41 Ring gear 41a Outer gear 41b Lock gear 41c Outer worm wheel 42 Pinion carrier 42a Output boss 43 First housing 44 Second housing 45 Third housing 46 Oil seal 47a Ball bearing 47b ball bear 47c bearing 48a bearing 48b bearing 49 sensor rod 50 manual lever 51 wire 52 lever member 53 shaft 54 manual gear 55 lock cam 56 lock pole 60 automatic transmission 61 transmission mechanism 62 inhibitor switch 63 CVT control unit 64 engine control unit 71 parking gear 71a parking cam 72 parking pole 72a parking pawl 73 spring 74 parking rod 74a parking cam 75 detent lever 101 sun gear 102 pinion gear 103 ring gear 103a output member 104 worm wheel 105 worm wheel 105a pinion carrier 106 electromagnetic clutch 108 first motor 108a first worm 109 No. Motor 109a second worm 111 rotating member 112 input shaft 113 output gear A planetary accommodating chamber B worm accommodating chamber

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Masayoshi Yoshino 1-1, Yoshiwara-cho, Fuji-shi, Fuji-shi, Shizuoka Prefecture F-term in JATCO Trans Technology Co., Ltd. (reference) 3J067 AA02 AA21 AB07 AB23 BA02 BA58 DA13 DA43 DA52 DB32 FA90 FB73 FB83 GA01

Claims (3)

[Claims] 1. A shift switch which is operated by a driver and outputs a switch signal indicating a shift position corresponding to each range such as a parking range and a drive range, and is provided in an automatic transmission, and drives a manual valve and a parking rod. A shift actuator, and a shift control unit that inputs a switch signal of the shift switch and outputs a command to obtain a shift position indicated by the switch signal to the shift actuator. A shift mechanism comprising: a planetary gear mechanism having a pinion carrier and a ring gear; a driving means connected to at least one of a sun gear or a ring gear; and an actuator output shaft connected to the pinion carrier. By-wire system. 2. The shift-by-wire system according to claim 1, wherein said shift actuator has a drive unit comprising: a first drive unit for driving said sun gear; and a second drive unit for driving said ring gear. Wherein one of the first and second drive means is a means driven by an electric motor and a worm gear, and the other means is a manual drive means which can be manually driven by a driver. By-wire system. 3. The shift-by-wire system according to claim 1, wherein said shift actuator has a drive unit comprising: a first drive unit for driving said sun gear; and a second drive unit for driving said ring gear. Wherein the first and second driving means are driven by an electric motor and a worm gear.