JPH01229146A - Automatic transmission - Google Patents

Abstract

PURPOSE:To improve the serviceability of a vehicle speed detecting mechanism, and to achieve the effective utilization of space by fitting the vehicle speed detecting mechanism on a shaft, and detachably connecting one end of the shaft to a countershaft, and further supporting the other end thereof on a case member. CONSTITUTION:A countershaft 5 is arranged in parallel to the axis of a gear speed change mechanism 3 (not shown). One end of a governor shaft 17 is detachably fitted in the spline 16 of the countershaft 5. A governor valve 18 being a vehicle speed detecting mechanism is held by the governor shaft 17. The other end of the governor shaft 7 is rotatably supported via a bushing 25. Thus, the serviceability of the vehicle speed detecting mechanism can be improved, and the effective utilization of space can be achieved.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to automatic transmissions for vehicles that automatically set gears according to vehicle speed and load.

As is well known in the art, an automatic transmission is configured to upshift as the vehicle speed increases if the load (specifically, throttle opening) is constant, and downshift as the load increases if the vehicle speed remains constant. Therefore, it is natural that the vehicle is equipped with an @ structure for detecting vehicle speed. For example, in a so-called hydraulically controlled automatic transmission that performs gear change control by directly replacing vehicle speed with oil pressure, a cabana valve is attached to a shaft that is substantially directly connected to the output shaft, so that the signal oil pressure is controlled by centrifugal force according to the vehicle speed. In electronic automatic transmissions that change gears electrically, a rotor is attached to a shaft that is virtually directly connected to the output shaft, and its rotational speed is picked up as a pulse signal, for example. .

Conventionally, various improvements have been made to the mounting structure of vehicle speed detection structures such as governor valves and rotors due to space constraints, serviceability requirements, and even the need for common parts. ing.

For example, the most common mounting structure for governor valves in automatic transmissions for front-mounted engine rear-wheel drive vehicles (FR vehicles) is to attach them to the output shaft that connects the propeller shaft with a snap ring, etc. Japanese Unexamined Patent Publication 1983
Publication No. 77153 discloses that a connecting shaft is provided between a rear wheel drive shaft (rear export force shaft) and a gear transmission mechanism mainly consisting of a planetary gear device, and is detachable from the gear transmission mechanism. A configuration is shown in which a gear for detecting vehicle speed is attached to improve serviceability. Also, front-engine front-wheel drive vehicles (
The most common governor valve mounting structure for VJ transmissions for FF vehicles is, for example, Utility Model Publication No. 58-132259.
As stated in the publication, a governor drive gear is attached to the counter shaft, and a driven gear is attached to the governor shaft arranged perpendicularly to the counter shaft (the governor is rotated through these gears). Furthermore, as a mounting structure for a vehicle speed detection mechanism in an automatic transmission for FF vehicles, for example, as described in JP-A-59-140943, the governor shaft is arranged parallel to the counter shaft and both are connected. A structure in which a spur gear is used for quick connection, and a structure in which a governor mechanism is mounted on the counter shaft itself, as shown in U.S. Pat. No. 4,095,487, are known.

Problems to be Solved by the Defense However, the configuration described in Japanese Patent Application Laid-Open No. 59-77153, which was first mentioned, places a clutch behind the gear transmission mechanism, and drives the rear export power shaft via the clutch. This is based on a structure that transmits force, and the input shaft for the clutch is a connecting shaft that can be attached to and detached from the gear transmission mechanism. It cannot be immediately applied to automatic transmissions for FF vehicles, and the
Since the configuration is such that a gear is attached to a connecting shaft and rotation is transmitted to the speed sensor via the gear, there is a problem that power loss in the gear A7 portion is large and its durability is deteriorated. On the other hand, in the configuration described in Japanese Utility Model Application Publication No. 58-132259, which is generally adopted for FF vehicles, the gears that transmit rotation to the governor are two 4-m wheels and two 4-m wheels, so the transmission efficiency is low. On top of this, the thrust force generated complicates the bearing configuration and reduces durability.Furthermore, the number of parts increases because the rotation of the counter shaft is transmitted to the governor via gears. It also causes some inconvenience. On the other hand, the configuration disclosed in JP-A-59-140943 transmits the rotation of the counter shaft to the governor shaft via a spur gear, so it has the advantage that no thrust force is generated.
Since the governor shaft is placed parallel to and covers the counter shaft, it may not be possible to adopt it if space constraints are severe.

In the configuration described in the above-mentioned U.S. Pat. Since it is placed in a deep position, there is an inconvenience that serviceability deteriorates.

The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide an automatic transmission in which a vehicle speed detection mechanism has good serviceability and space can be used effectively.

Means for Solving the Problems In order to achieve the above object, the present invention arranges a gear transmission mechanism on the same axis as the engine, and connects a counter shaft to which driving force is transmitted from the gear transmission mechanism to a gear transmission mechanism. In an automatic transmission that is arranged parallel to a transmission mechanism and whose counter shaft is rotatably supported by a casing, a vehicle speed detection mechanism that outputs a signal corresponding to the vehicle speed by rotation is attached to the shaft, and the shaft is connected to the counter shaft. The shaft is arranged on the same axis at the end of the shaft opposite to the engine side, and one end of the shaft is removably connected to the countershaft so that they rotate together, and the other end of the shaft is rotatably supported by a case member detachably attached to the casing.

Function: In the automatic transmission of this explanation, the rotation of the engine is increased or decreased based on the gear ratio set by the gear transmission mechanism, and is transmitted to the countershaft, and outputted from the countershaft to the front differential or the like. Therefore, the rotation of the counter shaft corresponds to the vehicle speed, and the vehicle speed detection mechanism rotates together with the counter shaft, and as a result, a hydraulic signal or an electric signal corresponding to the vehicle speed is output. The vehicle speed detector 114M has one end removably connected to and supported by the counter shaft, and the other end rotatably supported by the case member, so it can be removed by removing the case member from the casing. This will result in better serviceability. In addition, since the axial length of the counter shaft is generally shorter than that of a gear transmission mechanism, a space is often created on the opposite side of the counter shaft from the engine side. Therefore, in this invention, the vehicle speed detection mechanism cannot be placed in that space. , space can be used effectively.

Example Next, embodiments of the invention will be described with reference to the drawings.

The automatic transmission group of the present invention is mainly installed in a vehicle with a horizontally mounted engine, such as a front-wheel drive vehicle, and its driving force transmission system is schematically shown in FIG. 2. In other words, the engine 1 is placed horizontally in the width direction of the vehicle.
A torque converter 2 is connected to the output element of the torque converter 2, and a gear transmission mechanism 3 that changes speed according to the load and vehicle speed is connected to the output element of the torque converter 2, arranged on the same axis. This gear transmission mechanism 3 is disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 59-140.
This is a known device described in Japanese Patent Application No. 943, etc., and is mainly composed of a plurality of planetary gear devices, and is configured to perform three or four forward speeds and one reverse speed, and the counter drive gear 4 is connected to the engine 1 or Torque converter 2
is located on the same axis as the Also gear transmission 11*
A counter shaft 5 is arranged parallel to the axis of 3. This countershaft 5 is provided to set the output point at the center in the width direction of the vehicle body, and has a countertriangle meshed with the counter drive gear 4 at the end opposite to the engine side. A gear 6 is attached, and a front differential 7 and a front differential 7 are attached to the end on the engine side.
A final gear (tough drive gear) 8 is provided which meshes with the shaft.

The specific structure of the counter shaft 5 is shown in FIG. 1, and the counter shaft 5 is a shaft with the final gear 8 integrally formed at one end, and a counter driven gear at the other end. 6 is spline-fitted and rotatably supported by the transmission casing 11 via a tapered roller bearing 9 disposed adjacent to the final gear 8 and a tapered roller bearing 10 fitted to the boss portion of the counter driven gear 6. A sleeve 12 for preloading is fitted into the middle part of the counter shaft 5, and a crimping nut 13 is screwed into the other end of the counter shaft 5. By bending the sleeve 12, a load is applied in the axial direction to eliminate backlash. The countershaft 5 has a hollow structure for supplying lubricating oil, and the end on the engine side, that is, the opening on the final gear 8 side, is sealed with a plug 14, and the middle part is connected to the bearing 9, etc. An oil passage 15 is formed along the radial direction for sending lubricating oil. A spline 16 is formed on the inner periphery of the other end of the counter shaft 5, and one end of a governor shaft 17 is removably fitted therein. A governor valve 18, which is a vehicle speed detection mechanism, is held by the governor shaft 17.

The governor valve 18 has a known valve assembly 19 mainly composed of a valve, a weight, a spring, etc., held by a supporter 20, and has two oil passages 21a leading to the valve assembly 19,
21b passes through the interior of the supporter 20 and opens to the outer peripheral surface of the boss portion of the supporter 20. The governor valve 18 is spline-fitted to the outer periphery of the governor shaft 17.

On the other hand, a rear case 22 is detachably attached to a portion of the casing 11 on the side opposite to the engine 1 with bolts (not shown).
The extension length of the counter shaft 5 includes a first cylindrical portion 23 having an inner diameter approximately equal to the outer diameter of the boss portion of the supporter 20 and a second cylindrical portion 23 having an inner diameter slightly larger than the outer diameter of the governor shaft 17. The cylindrical portion 24 is formed on the same axis. The second cylindrical portion 24 has a governor shaft 17 whose negative end is spline-fitted to the counter shaft 5.
The other end of the supporter 20 is rotatably supported via a bushing 25, and a boss portion of the supporter 20 is rotatably supported on the inner peripheral surface of the first cylindrical portion 23 while maintaining liquid tightness. The fittings 21a and 21b communicate with an oil passage (not shown) opened in the inner circumferential surface of the first cylindrical portion 23.

A thrust direction shaft 1-26 is inserted roughly between the counter shaft 5 and the governor shaft 17, so that the supporter 2
0 and rear case 22, which thrust direction gap is correct! ! has been done.

The governor shaft 17 also has a hollow structure, and lubricating oil is supplied and discharged from a lubricating oil passage 27 formed in the rear case 22 to the inside of the counter shaft 5 through the inside of the governor shaft 17.

In the self-zero transmission with the above configuration, the rotation of the Iζ engine 1 is increased or decreased in the gear shift mechanism 3 and is transmitted to the counter shaft 5 via the counter drive gear 4 and the counter driven gear 6, and then from the final gear 8 to the front differential. 7. Therefore, the rotation speed of the counter shaft 5 corresponds to the output rotation speed. Since the governor shaft 17 is integrally connected to the counter shaft 5, the governor valve 18 rotates together with the counter shaft 5, and adjusts the oil pressure n1 according to its rotation speed.

In addition, the hydraulic pressure wJ is controlled via the hydraulic beam boat 20 generated here and an oil passage (not shown) formed in the rear case 22.
The signal is sent to the device and is used as a shift control signal.

When assembling the vehicle speed detection mechanism part of the above-mentioned automatic transmission, the governor valve 18 is connected to the governor shaft 1 in advance.
7 and assembled as a sub-assembly, and one end portion 12- of the governor shaft 17 is inserted into the counter shaft 5 with the thrust washer 26 interposed. With the bushing 25 fitted to the outer periphery of the other end of the governor shaft 17, the rear case 22 is
is attached to the casing 11, the boss portion of the supporter 20 is tightly fitted to the inner peripheral surface of the first cylindrical portion 23, and at the same time the other end portion of the governor shaft 17 is attached to the second cylindrical portion 24.
5 is interposed between them. Also governor valve 1
When performing repairs and inspections in step 8, remove it by following the steps opposite to the above steps.

Therefore, the governor shaft 17 has one end supported by the counter shaft 5 and the other end supported by the rear case 22. In this case, the counter shaft 5 is supported by a pair of tapered roller bearings 9 and 10. Since the governor valve 18 and the governor shaft 17 are supported in both the radial direction and the thrust direction, no load in the thrust direction is applied to the governor valve 18 or the governor shaft 17.

Although the above embodiment shows an example in which a governor valve is used as a vehicle speed detection mechanism, this light beam can also be applied to a so-called electronically controlled automatic transmission, and in that case, a governor valve is used as a vehicle speed detection mechanism. , a rotor with a magnet attached thereto and a magnetic sensor are used, and the rotor may be attached to a shaft in place of the governor shaft. Furthermore, in the above embodiment, the governor shaft is detachably connected to the counter shaft via a spline, but this explanation is not limited to the above embodiment, and the governor shaft and other shafts The connection with the counter shaft may be performed, for example, by a dog clutch, and any connection structure that is detachable may be sufficient.

Effects of the Invention As is clear from the above explanation, in the automatic transmission of this defense, the vehicle speed detection mechanism is attached to the shaft, one end of the shaft is detachably connected to the counter shaft, and the other end is attached to the case member. Since the vehicle speed detection mechanism is supported by the vehicle, the vehicle speed detection mechanism can be assembled separately as a so-called subassembly, and can be handled independently as a subassembly.Furthermore, the vehicle speed detection mechanism can be attached and detached by removing the case member. Therefore, according to the present invention, the serviceability of the vehicle speed detection mechanism is improved more than ever before. In addition, in the II4 construction of this Hikari automatic transmission, a shaft was detachably connected to the end of the counter shaft on the opposite side from the engine, and a vehicle speed detection mechanism was installed on that shaft, but the counter drive gear On the other hand, the part on the opposite side of the engine may protrude due to installation of an overdrive mechanism, etc., and it is advantageous to make it protrude in this way in order to make the counter shaft as rectangular as possible. Therefore, a space is likely to be created on the opposite side of the counter shaft from the engine, and the vehicle speed detection mechanism will be placed in that space between the lights. It is possible to promote downsizing of the machine. Furthermore, since this invention does not require parts such as gears to transmit rotation to the vehicle speed detection mechanism, it is possible to reduce the number of parts and reduce costs. Since the generated thrust load does not act on the vehicle speed detection mechanism,
Distortion of the vehicle speed detection mechanism can be prevented, and the shaft support structure can be simplified.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing the main parts of an embodiment of the present invention, and FIG. 2 is a schematic diagram showing a driving force transmission path of an automatic transmission vehicle that is a companion in the embodiment. 1... Engine, 3... Gear transmission mechanism, 5...
・Counter shaft, 6...Counter driven gear, 1
1...Transmission casing, 16...
・Spline, 17...Governor shaft, 18・
...Governor valve, 22...Rear case, 25.
...Butshu. Applicant Toyota Motor Corporation Representative Patent Attorney Yutaka 1) Hisashi Take (one idiot)

Claims (1)

[Scope of Claims] A gear transmission mechanism is arranged on the same axis as the engine, and a counter shaft to which driving force is transmitted from the gear transmission mechanism is arranged parallel to the gear transmission mechanism, and the counter shaft is rotated by a casing. In a freely supported automatic transmission, a vehicle speed detection mechanism that rotates to output a signal corresponding to the vehicle speed is attached to a shaft, and the shaft is mounted on the same end of the counter shaft on the opposite side from the engine side. The shaft is arranged on an axis, and one end of the shaft is detachably connected to the counter shaft so as to rotate together with the counter shaft, and the other end of the shaft rotates to a case member detachably attached to the casing. An automatic transmission characterized by being freely supported.