JPH04175545A - Automatic transmission - Google Patents

Abstract

PURPOSE:To accurately sense the revolving speed transmitted to the sun gear of a planetary gear unit without any special processing for sensing, by sensing the surface enevenness of a band brake drum, and determining the revolving speed. CONSTITUTION:At a constant spacing, notches or holes 157 are formed in a part adjacent to the spline engaging part A of a band brake drum 152a, and a revolving speed sensor 159 for example photo-electric or magnetic is installed in a part mating with a hole 157 in a transmission case 158. This sensor 159 can thus sense the revolving speed of a sun gear 155. As the band brake drum 152a is supported at a hub part 137b through a bushing 148, there is no generation of rattles with rotating, and it is practicable to locate the sensor 159 in the neighborhood of the band brake drum 152a, and accurate revolving speed can be sensed noiselessly without requiring increase in the sensing ability of the revolving speed sensor 159.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an automatic transmission equipped with a rotation speed detection device.

(Prior Art) Conventionally, an automatic transmission for a vehicle has a plurality of planetary gear units each consisting of a sun gear, a carrier that rotationally supports a pinion gear, and a ring gear.
By inputting rotation from the engine to a predetermined element of each of these planetary gear units and outputting it from the predetermined element, the rotation speed input from the engine is changed to a rotation speed corresponding to the gear position and output to the drive wheels. That's what I do.

In controlling the automatic transmission with the above configuration to achieve a predetermined gear, various rotational speeds such as throttle opening, vehicle speed, etc., human rotation speed, output rotation speed, etc. are detected, and each parameter is input to the control device. Various controls are performed by doing so (see Japanese Patent Application Laid-Open No. 62-31741).

FIG. 5 is a sectional view of essential parts of a conventional automatic transmission.

In the figure, reference numeral 1 denotes an automatic transmission, which includes a fluid transmission device (not shown), a planetary gear transmission 3, and a hydraulic control mechanism, which are housed in a converter housing, a transmission case 7, and an extension housing, respectively. The fluid transmission device transmits the rotation input from the engine to the input shaft of the planetary gear transmission 3 via an oil flow of the fluid transmission device or via a lock-up flanch.

The planetary gear shift I3 has an overdrive (not shown) (0
/D) It is composed of a sub-transmission unit consisting of a planetary gear unit, and a main transmission unit 21 consisting of a front planetary gear unit 19 and a rear planetary gear unit (not shown). The above overdrive planetary gear unit has a pinion gear that is directly connected to the input shaft.
Sun gear and main transmission unit 21 surrounding the input shaft
An overdrive direct clutch C0 and a one-way clutch F are interposed between the pinion gear and the sun gear, and an overdrive brake B0 is interposed between the sun gear and the transmission case 7. It is arranged.

In addition, the front planetary gear unit 19 is connected to the output shaft 2.
7, a sun gear 30 that surrounds the output shaft 27 and is integrated with the sun gear of the rear planetary gear unit, and a ring gear 33 that is connected to the input shaft 26 via a forward clutch C1.
Consists of.

Further, a direct clutch C2 is interposed between the input shaft 26 and the sun gear 30, a band brake (first coast brake) Bl is interposed between the acid sun gear 30 and the case 7, and a one-way clutch F1
A second brake B2 is disposed via the second brake B2.

Further, the rear planetary gear unit includes a pinion gear, a sun gear 30, and a ring gear directly connected to the output shaft 27, and a fast and reverse brake and a one-way clutch are arranged in parallel between the pinion gear and the case 7.

Reference numeral 10 denotes a cylinder of a hydraulic servo B-0 that engages and disengages the overdrive brake B, and its sleeve portion 10a rotatably supports the input shaft 26 through a bearing 11.

C2 is a hydraulic servo for direct clutch Ct,
Consisting of a cylinder 14 and a piston 15, the cylinder 1
The inner annular body 16 of 4 is connected to the sleeve 1 through a bush 17.
8 and is rotatably supported.

The cylinder 14 has a connecting drum 2 at its periphery.
4, and the connecting drum 24 is spline connected to the sun gear 30. In addition, the connecting drum 24
is spline-connected at the part indicated by A in the figure, and consists of a band brake drum 24a and a sun gear input drum 24b, and surrounds the direct clutch C1, forward clutch CI, and front planetary gear unit 19 inside.

Further, 28 is a hydraulic servo C1 of the forward clutch C1.
It is a cylinder.

Cutouts or holes 35 are formed at equal intervals in a portion of the sun gear input drum 24b adjacent to the spline connection portion A. On the other hand, in a portion of the transmission case 7 corresponding to the hole 35, a rotation speed sensor 36 made of a photoelectric sensor, a magnetic sensor, or the like is installed. Therefore, the rotation speed sensor 36 is connected to the sun gear 30
The rotational speed of the main transmission unit 21, that is, the state of gear change by the main transmission unit 21 can be detected.

(Problem II to be Solved by the Invention) However, in the automatic transmission with the above configuration, the sun gear input drum 24b of the connecting drum 24 has a hole 35.
Since the rotation speed sensor 36 detects the rotation speed by sensing the hole 35, it is not possible to accurately detect the rotation speed.

That is, the sun gear input drum 24b of the connecting drum 24 in which the sensor ring hole 35 is formed is spline connected to the band brake drum 24a at one end, and spline connected to the sun gear 30 at the other end. The support becomes unstable and looseness is likely to occur.

Therefore, the rotation speed sensor 36 is installed at a distance that does not touch the sangya input drum 24b, and the rotation speed sensor 36 has a correspondingly high sensor capability.
It is necessary to provide 6.

However, when the rotation speed sensor 36 with high sensor capability is installed, it picks up the rotation speed of the cylinder 28 of the hydraulic servo C1 installed to engage and disengage the forward clutch C1, and the rotation speed of the sun gear input drum 24b increases. In other words, the cylinder 28 of the hydraulic servo CI needs to be spline-engaged with a clutch thin plate on its inner circumferential side, and a plurality of concave and convex portions are formed on its outer circumference. Therefore, if a powerful rotational speed sensor 36 is used, the above-mentioned unevenness will be sensed and the rotational speed of the input shaft 26 will be detected.

In addition, in order to improve the detection ability of the rotation speed sensor 36,
It is necessary to process the surface of the sun gear input drum 24b to increase the roundness and reduce the surface roughness, which increases the work cost due to the process.

The present invention solves the problems of the conventional automatic transmission described above, and
The purpose of this invention is to provide an automatic transmission that can accurately detect the rotational speed input from the input shaft and transmitted to the sun gear of a planetary gear unit, and that does not require special processing to detect the rotational speed. do.

(Means for Solving the Problems) To achieve this, in the automatic transmission of the present invention, the transmission case is rotatably supported by a bearing, a handbrake is disposed on the outside so that it can be engaged and detached, and an input input is provided on the inside. A band brake drum provided with a clutch that selectively transmits rotation from the shaft, spline connected to the band brake drum and spline connected to a sun gear of a planetary gear unit to transmit rotation of the band brake drum to the sun gear. It has a sun gear input drum.

A rotation speed sensor is attached to the transmission case facing the band brake drum, and detects the rotation speed by sensing irregularities formed on the surface of the band brake drum.

(Operations and Effects of the Invention) According to the present invention, as described above, the transmission case is rotatably supported by a bearing, the band brake is detachably disposed on the outside, and the rotation from the input shaft is provided on the inside. a sun gear input drum that is spline-connected to the band brake drum and spline-connected to the sun gear of the planetary gear unit to transmit the rotation of the band brake drum to the sun gear; It has

Therefore, rotation input from the input shaft is transmitted to the sun gear by engaging the clutch.

A rotation speed sensor is attached to the transmission case facing the band brake drum, and detects the rotation speed by sensing irregularities formed on the surface of the band brake drum.

That is, since the band brake drum is rotatably supported by a bearing relative to the transmission case, there is no play caused by rotation, and the rotation speed sensor can be disposed close to the band brake drum. Therefore, the rotation speed can be accurately detected without noise without increasing the sensor capability of the rotation speed sensor.

In addition, the band brake drum, on which the unevenness detected by the rotation speed sensor is formed, is surface-treated in order to engage and disengage the band brake, so there is no need for additional surface treatment. The associated work costs will not increase.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

FIG. 2 is a sectional view of the automatic transmission of the present invention.

This automatic transmission is a planetary gear consisting of a first planetary gear transmission mechanism 110 connected in series between a fluid transmission bag 2100 and a Lugya 300 during differential arrangement, and a second planetary gear transmission mechanism 120 connected in parallel in the opposite direction. A transmission mechanism 200 is provided.

The fluid transmission device 100 includes a front cover 102 connected to an engine output shaft 101, a pump impeller 103 connected to the front cover 102, a turbine runner 105 connected to a fluid transmission device output shaft 104a, and a one-way clutch 106. This torque converter consists of a stator 107 connected to the case of an automatic transmission, and a direct clutch 108.

The first planetary gear transmission mechanism 110 includes an output shaft 11 disposed in series with the fluid transmission device output shaft 104a, that is, the human power shaft 104 of the transmission and the input shaft 104.
1 between the first planetary gear unit 13 and the second
It has a planetary gear unit 114. Also,
A forward clutch C, a direct clutch C3, a second coast brake B++, and a second brake B, which engage or release the components of these planetary gear units) 113 and 114 to perform underdrive of three forward speeds and one reverse speed.

Fast and reverse brake Bff, one-way clutch F + , F z and each of the above clutches c,
C.

and each brake B1. Bz, hydraulic servo CI that operates Bz, C2, Bl (not shown), B2. B
3, and an output gear 112 is attached to the end of the output shaft 111 (the end opposite to the fluid transmission device 100).

On the other hand, the second planetary gear transmission mechanism 120 has an input shaft 121 disposed parallel to the output shaft of the first planetary gear transmission mechanism 110, and an end portion of the input shaft 121 on the fluid transmission device side that rotates. A third planetary gear unit 124 is freely fitted to the outside and is connected to an output shaft 123 supported by the input shaft 121, and components of the third planetary gear unit 124 are engaged or released to achieve two forward stages. First and reverse clutch C1, underdrive brake B4, one-way clutch F1, which performs underdrive.
and a hydraulic servo C3 that operates these first and reverse clutch C3 and underdrive brake B4.
, B4, an input gear 122 that meshes with the output gear 112 of the first planetary gear transmission mechanism 110 is attached to the end of the input shaft 121, and an output gear 125 is formed on the output shaft 123. .

The differential gear 300 is a large drive gear 30 that meshes with the output gear 125 of the second planetary gear transmission mechanism 120.
11 gearbox 302, a differential gear 303, and output shafts 304 and 305 connected to an axle.

The transmission device with the above configuration includes a torque converter housing 410 whose fastening surface 400^ to the engine is open and forms a torque converter room 411 in which the torque converter 100, which is a fluid transmission device, is housed, and a differential whose side surface opposite to the engine is open. A torque converter case 400 consisting of a differential housing 420 forming a differential gear room 421 in which the gear 300 is housed; a first room 510 in which the first planetary gear transmission mechanism 110 is housed; A room 510 is separated from the second planetary gear transmission mechanism 120.
A transmission case 500 consisting of a second room 520 in which the differential housing 420 is housed and a side wall 502 of the differential arrangement room that covers the opening of the differential housing 420, and a wall of the transmission case 500 on the side opposite to the torque converter (or engine). The gear cover 600 is mounted in an automatic transmission case that includes a connected gear cover 600.

Next, the rotation speed detecting means in the automatic transmission of the present invention will be explained based on FIGS. 1 and 3.

FIG. 1 is a sectional view of essential parts of an automatic transmission according to the invention, and FIG. 3 is a sectional view of a band brake drum in the automatic transmission according to the invention.

In the figure, 104 is an input shaft to which rotation from the fluid transmission device 100 (FIG. 2) is input, and 135 is the input shaft of the fluid transmission device 1.
a stator shaft connected to the stator 107 of 00;
136 is a hydraulic pump for supplying oil to the hydraulic circuit;
37 is a pump cover that covers the hydraulic pump 136.

The pump cover 137 has a flange portion 137a facing the hydraulic pump 136 and the stator shaft 135.
The hub portion 137b surrounds the hub portion 137b.

Reference numeral 138 denotes a lubricating oil passage, and 139 to 140 denote oil passages for supplying oil to the hydraulic servo C2 of the direct clutch C2. Extends.

The hydraulic servo C2 has a cylinder 145 and a piston 146.
The inner annular body 147 of the cylinder 145 is rotatably supported by the hub portion 137b via a bush 148. Further, the input shaft 104 is rotatably supported by a stator shaft 135 via a bearing 149.

Then, the input shaft 104 and the stator shaft 135
A seal ring 150 is disposed between the hub portion 137b and the inner annular body 147 of the cylinder 145, and a seal ring 151 is disposed between the hub portion 137b and the inner annular body 147 of the cylinder 145 to seal the oil in each of the oil passages 138 and 140.

Further, the cylinder 145 is connected at its peripheral edge to a connecting drum 152, and the connecting drum 152 is spline connected to the sun gear 155 of the first planetary gear unit 113. In addition, the connecting drum 15
2 is spline-connected at the part indicated by A in the figure, and consists of a band brake drum 152a and a sun gear input drum 152b, and surrounds the direct clutch Cz, forward clutch C1, and front planetary gear unit 19 inside.

Further, 156 is the hydraulic servo C of the forward clutch C1.
1 cylinder.

Cutouts or holes 157 are formed at equal intervals in a portion of the band brake drum 152a adjacent to the spline connection portion A. On the other hand, in a portion of the transmission case 158 corresponding to the hole 157, a rotation speed sensor 159 made of a photoelectric sensor, a magnetic sensor, or the like is installed. Therefore, the rotation speed sensor 159 can detect the rotation speed of the sun gear 155.

In this case, since the band brake drum 152a is supported by the hub portion 137b via the bushing 148, no backlash occurs due to rotation, and the rotation speed sensor 1
59 can be disposed adjacent to the band brake drum 152a. Therefore, the rotation speed can be accurately detected without noise without increasing the sensor capability of the rotation speed sensor 159.

Furthermore, since the handbrake drum 152a in which the hole 157 to be sensed by the rotational speed sensor 159 is formed is surface-treated to engage and disengage the band brake B+, there is no need to perform surface treatment again. There is no increase in work costs associated with processing.

Next, a second embodiment of the present invention will be described based on FIG. 4.

FIG. 4 is a sectional view of essential parts of an automatic transmission showing a second embodiment of the present invention.

In this embodiment, the rotation speed sensor 159 is attached to the front end of the band brake drum 152a, that is, on the oil pump side, and the hole 157 is also attached to the front end of the band brake drum 152a.
formed at the front end of the

Note that the present invention is not limited to the above embodiments,
Various modifications are possible based on the spirit of the present invention, and these are not excluded from the scope of the present invention.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of essential parts of an automatic transmission of the present invention, FIG. 2 is a cross-sectional view of the automatic transmission of the present invention, FIG. 3 is a cross-sectional view of a band brake drum in the automatic transmission of the present invention, and FIG. The figure is a sectional view of a main part of an automatic transmission showing a second embodiment of the present invention, and FIG. 5 is a sectional view of a main part of a conventional automatic transmission. 104... Input shaft, 113... First planetary gear unit, 152a... Band brake drum, 1
52b... Sun gear input drum, 157...
Hole, 158... Transmission case, 159...
・・Rotation speed sensor, BI・Band brake, CI・
...Forward clutch, C2...Direct clutch. Patent applicant: Aisin AW Duburi Ni Co., Ltd. Agent: Patent attorney: Makoto Kawagoi (2 others) / 29 / Procedural amendment (voluntary) December 7, 1990

Claims (1)

[Claims] A band brake drum rotatably supported by a bearing relative to a transmission case, having a band brake detachably disposed on the outside and a clutch for selectively transmitting rotation from an input shaft on the inside; a sun gear input drum that is spline-connected to the band brake drum and spline-connected to the sun gear of the planetary gear unit to transmit the rotation of the band brake drum to the sun gear; An automatic transmission characterized by having a rotation speed sensor that detects the rotation speed by sensing irregularities formed on the surface of a band brake drum.