JP2002349667A - Automatic transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To supply a working fluid into a predetermined part of a gear change mechanism to be supplied, without using a part such as a valve. SOLUTION: A transmission case of the automatic transmission has a main case for storing the gear change mechanism, and a convertor case 10a is connected on a jointed surface in the main case. A controller housing chamber 57 is provided in a transmission casing, a valve is assembled in the transmission casing 57, and also the working fluid is stored therein. A high-pressure hydraulic passage for supplying the working fluid into hydraulic equipment, such as a clutch for forwarding is formed in the transmission case, the through-hole is opened on the jointed surface, and a low-pressure hydraulic passage for guiding the working fluid into the part to be supplied in the transmission case is formed on the jointed surface of the main casing and the convertor case at a lower part of the through-hole.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic transmission,
In particular, the present invention relates to an automatic transmission useful for a transmission case having a lubrication circuit for lubricating a belt-type continuously variable transmission as a transmission mechanism.

[0002]

2. Description of the Related Art An automatic transmission has an ordinary automatic transmission (AT) using a planetary gear or the like as a speed change mechanism, and a metal belt between two pairs of pulleys having a variable groove width as a speed change mechanism. Is continuously variable (CVT). Further, an automatic transmission (A) of a type in which a transmission gear train for transmitting power is automatically switched by a hydraulic actuator based on the structure of a manual transmission having a plurality of transmission gear trains.
MT). In these automatic transmissions, an oil pump is used as a drive source for a shift operation, and hydraulic oil supplied from the oil pump is also used for lubrication of each member constituting the transmission mechanism. .

For example, a speed change mechanism of a belt-type continuously variable transmission has a groove width in which a metal belt is stretched between a primary pulley provided on an input shaft and a variable groove width and a primary pulley provided on an output shaft. And a variable secondary pulley, which are incorporated in the main case. A converter case accommodating a torque converter is connected to the main case. A forward / reverse switching device for switching the rotation of the converter output shaft between the forward direction and the reverse direction is incorporated in the main case, and the main case and the converter case constitute a transmission case.

[0004] In order to change the gear ratio by adjusting the groove width of each pulley, a drive oil chamber is provided on the movable pulley of each pulley, and the operating oil from the oil pump is regulated to drive the oil chamber. Supplied to Further, the hydraulic oil is regulated and supplied to operate the friction engagement element provided in the forward / reverse switching device. Furthermore, in the case of a belt-type continuously variable transmission, hydraulic oil for lubrication is supplied to the contact surface between the belt of the speed change mechanism and each pulley, and the centrifugal hydraulic pressure generated by the rotation of the pulley is offset to each pulley. Hydraulic oil is also supplied to the balance oil chamber formed for the purpose.
The pressure of the hydraulic oil supplied to these lubrication and balance oil chambers is set to a pressure lower than the pressure of the hydraulic oil supplied to the groove width adjustment of the pulley or to the forward / reverse switching device.

[0005]

Conventionally, the supply of hydraulic oil to a lubricating portion and a balance oil chamber is performed by guiding hydraulic oil regulated by a pressure control valve using a pipe incorporated in a main case. I have to. For example, in order to supply hydraulic oil to a balance oil chamber of a secondary pulley, hydraulic oil discharged from a pressure control valve is supplied to oil passages formed in a main case, an oil pump cover, an oil pump housing, and a converter case, respectively. , And further to another oil passage formed in the converter case by a pipe, and hydraulic oil is supplied into the balance chamber from this portion. Therefore, conventionally, it has been necessary to form an oil passage by machining after casting the main case, the oil pump cover, and the like.

[0006] Attempts to form an oil passage by a mating surface of two cases constituting a transmission case for an AT have been made, for example, in Japanese Patent Application Laid-Open Nos. 2-19968 and 6-331.
No. 027 is disclosed. However, when an oil passage is formed between the two cases by abutting the mating surfaces of the two cases, if the hydraulic oil flowing through the oil passage is at a low pressure such as lubrication of a sliding portion in the transmission mechanism, Oil leakage from the mating surface does not occur, but if the pressure of the working oil flowing through the oil passage is high, it is not possible to avoid oil leakage from the mating surface.

SUMMARY OF THE INVENTION It is an object of the present invention to supply hydraulic oil to a predetermined portion of a transmission mechanism without using parts such as pipes.

Another object of the present invention is to make it possible to use leakage of hydraulic oil supplied to a hydraulic device in a transmission mechanism as low-pressure hydraulic oil such as lubrication.

[0009]

The automatic transmission according to the present invention comprises:
A main case that houses a transmission mechanism that transmits the rotation of the input shaft to the output shaft at a speed, and a torque converter that is arranged between the engine and the transmission mechanism, and is joined to the main case to form a transmission case. And a high-pressure oil passage that guides hydraulic oil from a hydraulic oil storage portion provided in the transmission case to hydraulic equipment in the transmission case. A low-pressure oil passage formed through the mating surface and guiding hydraulic oil from the hydraulic oil storage portion to a supplied portion in the transmission case; and a high-pressure oil passage formed on a mating surface between the main case and the converter case. Is formed by a groove below the through portion.

In the present invention, since the low-pressure oil passage is formed on the mating surface of the main case and the converter case, it is not necessary to incorporate a pipe for the low-pressure oil passage into the transmission case. Since the low-pressure oil passage is provided below the through portion of the high-pressure oil passage, the hydraulic oil leaked from the high-pressure oil passage can be used as the low-pressure hydraulic oil.

[0011]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a schematic diagram showing an example of a drive system of a belt-type continuously variable transmission, that is, a CVT. The rotation of a crankshaft 1 driven by an engine (not shown) is controlled by a torque converter 2 as a starting device and a forward / reverse switching device. 3 and transmitted to the continuously variable transmission main body 4.

The torque converter 2 has a converter case 1
0a, the forward / reverse switching device 3 and the continuously variable transmission body 4 are accommodated in a main case 10b, and the converter case 10a is joined to the main case 10b at one mating surface of the main case 10b. The side case 10c is joined to the other mating surface of the. The transmission case 10 is constituted by these cases 10a to 10c.

The torque converter 2 has a lock-up clutch 5, and the lock-up clutch 5 is connected to a turbine shaft 6. One side of the lock-up clutch 5 is a supply chamber, that is, an apply chamber 7a, and the other side is an open chamber, that is, a release chamber 7b, and the hydraulic pressure supplied to the release chamber 7b is circulated through the apply chamber 7a to thereby perform torque conversion. 2 is activated. On the other hand, by supplying hydraulic pressure to the apply chamber 7a and reducing hydraulic pressure in the release chamber 7b, the lock-up clutch 5 is engaged with the front cover 8 to be in a lock-up state. By adjusting the pressure in the release chamber 7b, slip pressure control is performed so that the lock-up clutch 5 is slid.

The forward / reverse switching device 3 is a forward clutch 11 for transmitting the rotation of the turbine shaft 6 as an output shaft of the torque converter 2 to the continuously variable transmission main body 4 in a forward direction, and a forward clutch 11 for transmitting the rotation in a reverse direction. And a reverse brake 12.
When hydraulic pressure is supplied to the clutch oil chamber 11a of the forward clutch 11 to bring the forward clutch 11 into the connected state, the rotation of the turbine shaft 6 is transmitted to the continuously variable transmission main body 4 in the forward direction, and the reverse brake 12 is braked. When the hydraulic pressure is supplied to the oil chamber 12a to set the reverse brake 12 in the connected state, the reverse brake 12 is decelerated and transmitted in the opposite direction.

The continuously variable transmission main body 4 has an input shaft connected to the forward / reverse switching device 3, ie, a primary shaft 13, and an output shaft parallel to the input shaft, ie, a secondary shaft 14. A primary pulley 15 is provided on the primary shaft 13, and the primary pulley 15 is
And a movable pulley 15b mounted on the primary shaft 13 so as to be slidable in the axial direction by a ball spline or the like in opposition to the fixed pulley 15a. It is variable.
A secondary pulley 16 is provided on the secondary shaft 14, and the secondary pulley 16 slides in the axial direction on the secondary shaft 14 in opposition to the fixed pulley 16a fixed to the secondary shaft 14 like the movable pulley 15b. A movable pulley 16b that is freely mounted, and the groove width of the pulley is variable.

A belt 17 is stretched between the primary pulley 15 and the secondary pulley 16, and by changing the groove width of both pulleys 15, 16, the ratio of the winding diameter to the respective pulleys 15, 16 is changed. Is changed, the rotation of the primary shaft 13 is transmitted to the secondary shaft 14 at a continuously variable speed. The rotation of the secondary shaft 14 is transmitted via a reduction shaft 18 having a reduction gear and a differential device 19 to the drive shafts 20a and 20b.
And the wheels are driven. In the case of a front wheel drive vehicle, the wheels are front wheels.

A plunger 21 is fixed to the primary shaft 13 of the continuously variable transmission main body 4 in order to change the groove width of the primary pulley 15, and a primary cylinder 22 slidably contacting the outer peripheral surface of the plunger 21. The drive oil chamber 23a is fixed to the movable pulley 15b, and is formed between the plunger 21 and the movable pulley 15b. On the other hand, a balance oil chamber 23b is formed between the cover 24 provided at the opening end of the primary cylinder 22 and the plunger 21.

To change the groove width of the secondary pulley 16, a plunger 26 is fixed to the secondary shaft 14, and a secondary cylinder 27 slidably contacting the outer peripheral surface of the plunger 26 is fixed to the movable pulley 16b. A driving oil chamber 28a is formed between the plunger 26 and the movable pulley 16b. On the other hand, a balance oil chamber 28b is formed between the plunger 26 and the cover 29 provided at the opening end of the secondary cylinder 27. To operate hydraulic devices such as the forward clutch 11 and the reverse brake 12, an oil pump 31 is connected to a pump-side case of the torque converter 2, and the oil pump 31 is driven by an engine.

FIG. 2 is a circuit diagram showing the hydraulic control device of the CVT shown in FIG. 1. The torque converter 2, the forward / reverse switching device 3, and the continuously variable transmission body 4 are driven by an oil pump 31 driven by an engine. It is designed to be operated by the hydraulic pressure. The suction port of the oil pump 31 communicates with the oil pan 32, and the discharge port of the oil pump 31 is connected to the drive oil chamber 28 by a secondary pressure path, that is, a line pressure path 33.
a and is connected to the secondary pressure port of the secondary valve 34. By this secondary valve 34, the secondary pressure supplied to the drive oil chamber 28a is adjusted to a pressure corresponding to the transmission capacity required for the belt 17. The line pressure passage 33 is connected to a line pressure port of the primary valve 35, and the primary pressure port of the primary valve 35 is connected to the drive oil chamber 23 a via the primary pressure line 36. The primary pressure is adjusted by the primary valve 35 to a pressure according to the target gear ratio, the vehicle speed, and the like, and the vehicle speed is controlled by changing the groove width of the primary pulley 15.

The line pressure passage 33 is connected to a clutch pressure passage 38 via a clutch pressure valve 37. The forward clutch 11 of the forward / reverse switching device 3 is connected via the clutch pressure passage 38.
, A brake oil chamber 12a for the reverse brake 12, and an apply chamber 7a for the lock-up clutch 5.
Then, hydraulic oil of clutch pressure is supplied. The lubricating oil passage 3 is connected to the drain port of the secondary valve 34.
9 is connected, and the oil pressure in the lubricating oil passage 39 is adjusted by a lubricating pressure adjusting valve 40. The adjusted hydraulic oil is supplied to the lubricating portion of the forward / reverse switching device 3 and the lubricating portion of the belt 17, and is also supplied to the balance oil chamber 28b of the secondary pulley 16.

Apply chamber 7a of lock-up clutch 5
, A release pressure path 42 connected to the release chamber 7b, a brake switching pressure path 43 connected to the brake oil chamber 12a, and a clutch oil chamber 11a.
A switch valve 45 is provided in the hydraulic control device for controlling the connection between the clutch switching pressure path 44 connected to the lubrication pressure path 39 and the clutch pressure path 38 described above. The switch valve 45 has four portions each having a three-port switching valve structure. When the external pilot pressure is not applied as shown in FIG. Is actuated to the position where the lock-up clutch 5 is engaged.

In the open position, the hydraulic oil set at the lubricating pressure is supplied to the release chamber 7b, discharged from the apply chamber 7a, and returned to the oil pan. On the other hand, at the engagement position, the clutch pressure path 38 and the apply pressure path 41 are in communication with each other, and the operating oil set to the clutch pressure is supplied to the apply chamber 7a. At this time, the clutch pressure path 3
The slip pressure passage 46 connected to the pressure passage 8 communicates with the release pressure passage 42. The slip pressure adjusting valve 4 is provided in the slip pressure path 46.
The slip pressure adjusting valve 47 controls the slip pressure supplied to the slip pressure passage 46 according to the external pilot pressure supplied to the external pilot chamber of the slip pressure adjusting valve 47 by the operation of the solenoid valve 48. Control.

A manual valve 52 and a reverse signal valve 53, which are linked to each other, are connected to a control lever for selecting a traveling mode, that is, a select lever 51 provided in the vehicle interior.
Reference numeral 53 operates at five positions corresponding to the P (parking) range, R (reverse) range, N (neutral) range, D (drive) range, and Ds (sports drive) range set by the select lever 51.

When the R range is selected, the hydraulic pressure is supplied to the reverse brake oil chamber 12a via the switch valve 45 and the manual valve 52, and when the forward travel range such as the D range is selected, the forward clutch is selected. Oil pressure is similarly supplied to the oil chamber 11a. On the other hand, a switch valve 4 is provided for the apply chamber 7a and the release chamber 7b of the torque converter 2.
When the hydraulic pressure is supplied through the lock 5 and the lock-up clutch 5 of the torque converter 2 is locked, the lock-up valve 49 is operated and the pilot pressure is supplied to the switch valve 45. These hydraulic devices include a clutch pressure valve 37.
High-pressure hydraulic oil is supplied. On the other hand, the hydraulic oil whose pressure has been adjusted to a low pressure by the lubrication pressure adjusting valve 40 is supplied to the belt 17 and the lubricating portion of the forward / reverse switching device 3 as the supplied portion and to the balance oil chamber 28b.

FIG. 3 is a front view showing the mating face of the converter case 10a with the main case 10b, and FIG. 4 is a front view showing the main case 10b abutting on one end face of the converter case 10a. FIG. 5 (A)
5 is a sectional view taken along line AA in FIG. 3, and FIG.
FIG. 5B is a sectional view taken along the line BB in FIG. 4, and FIG. 5C is a sectional view taken along the line CC in FIG.

The mating surface 55 formed on the main case 10b is indicated by hatching in FIG. 4, and is formed on the converter case 10a.
The mating surfaces 54 that are abutted against are indicated by hatching in FIG. As shown in FIGS. 3 and 4, the primary shaft 13, the secondary shaft 14, and the reduction shaft 18
And the drive shafts 20a, 20b
a and 10b to be rotatably supported.

A controller housing wall 56 is formed on the upper part of each of the cases 10a and 10b so as to protrude upward. When the two cases 10a and 10b are brought into contact with the respective mating surfaces 54 and 55, the respective controllers 10a and 10b are brought into contact with each other. One controller storage room 5 is provided by the controller storage wall 56.
7 is formed. The clutch pressure valve 37, the slip pressure adjusting valve 47, the solenoid valve 48, the lock-up valve 49, the manual valve 52, and the reverse signal valve 53 shown in FIG. The pressurized hydraulic oil is stored. On the other hand, the secondary valve 34, the primary valve 35, and the lubrication pressure adjusting valve 40 shown in FIG. 2 are incorporated in the lower part of the transmission case 20.

As shown in FIG. 4, the controller storage chamber 57 communicates with a clutch port 61 communicating with the clutch oil chamber 11a, a lock-up port 62 communicating with the apply chamber 7a of the torque converter 2, and a release chamber 7b. A release port 63 is provided, and the hydraulic oil whose pressure has been adjusted and the oil passage has been switched by a valve such as the clutch pressure valve 37 is supplied to each port. The hydraulic oil supplied through these ports 61 to 63 is supplied to the lock-up clutch 5 and the forward brake 1.
1, the pressure is set to a relatively high pressure.

The hydraulic oil supplied from each of the ports 61 to 63 is guided to the primary shaft 13 via the high-pressure oil passages 61a to 63a, and supplied to the forward clutch 11 and the lock-up clutch 5 as hydraulic devices, respectively. You. As shown in FIGS. 3 and 4, each of the high-pressure oil passages 61a to 63a is provided with a mating surface 55 of the main case 10b.
And the converter case 10a penetrate the mating surface 54, and reference numerals 61b to 63b each denote a penetrating portion.

The controller storage chamber 57 contains a working oil L whose pressure is adjusted by the lubrication pressure adjusting valve 47 and has a lower pressure than the working oil flowing through the high-pressure oil passages 61a to 63a. As shown, it flows into a low-pressure port 64 provided in the controller storage chamber 57. The low-pressure oil passage 65 provided in the low-pressure port 64 is
As shown in FIG. 4, the mating surface 55 of the main case 10b
In the opening 65a. Converter case 10
4, a guide hole 66 for supplying lubricating oil to a contact surface between the belt 17 and each of the pulleys 15 and 16 is formed as shown in FIG. Also, the main case 10b
3, a guide hole 67 for supplying hydraulic oil to the balance oil chamber 28b of the secondary pulley 16 is formed.

Semicircular grooves 68a, 68b are formed in the mating surfaces 54, 55 of the respective cases 10a, 10b so as to be positioned below the penetrating portions 61b to 63b. Each groove 68a, 68b has two cases 10
When the two cases 10a, 10b are joined at their mating surfaces 54, 55, the opening 65a of the lubricating oil passage 65 is formed.
A low-pressure oil passage extending between the transmission case 20 and the respective guide holes 66, 67 is formed in the transmission case 20 by the respective grooves 68a, 68b.

Accordingly, the hydraulic oil L in the controller storage chamber 57 is supplied to the mating surface 5 of the cases 10a and 10b without providing a pipe in the transmission case 10.
Belt 17 through a low pressure oil passage formed by
And the balance oil chamber 28a. Moreover, since the grooves 68a, 68b can be easily formed when the cases 10a, 10b are cast by die casting, components for forming the low-pressure oil passage and the cases 10a, 68b are formed.
The machining of 10b becomes unnecessary, and the manufacturing cost of the transmission case 10 can be reduced.

The mating surfaces 54, 55 of the cases 10a, 10b are provided with through-holes 6 of the high-pressure oil passages 61-63.
1b to 63b are provided above the low-pressure oil passage, and the hydraulic oil leaked from the high-pressure oil passages 61 to 63 to the mating surfaces 54 and 55 enters the low-pressure oil passage. Thus, the hydraulic oil leaked from the high-pressure oil passage can be used as low-pressure oil such as lubricating oil. Further, the controller storage chamber 57 is formed by combining the two cases 10a and 10b. Even if the hydraulic oil in the controller storage chamber 57 leaks into the mating surfaces 54 and 55, the hydraulic oil is low-pressure oil. It can enter the road and be used as low-pressure oil such as lubricating oil. As described above, the hydraulic oil leaked from the high-pressure oil passage and the controller storage chamber 57 can be used as low-pressure hydraulic oil such as lubricating oil.
Leakage oil can be prevented from leaking out of the transmission case 10.

The present invention is not limited to the above embodiment, and it goes without saying that various changes can be made without departing from the spirit of the present invention. For example, low-pressure oil passages are formed in semicircular grooves 6 formed in respective cases 10a and 10b.
8a and 68b are combined to form a circular cross section. However, if a cross-sectional area required for a low-pressure oil passage is secured, a groove is formed only in one case and the mating surface of the other case is flat. Alternatively, a low-pressure oil passage having a semicircular cross section may be used. Although the illustrated embodiment is a case where the present invention is applied to a transmission case of a continuously variable transmission (CVT), the present invention may be applied to a normal automatic transmission (AT) and an AMT.

[0035]

According to the present invention, a low-pressure oil passage for supplying low-pressure hydraulic oil to a supplied portion such as a lubricating portion in a transmission case is formed by a mating surface of a main case and a converter case. Therefore, it is not necessary to provide parts such as pipes or to perform machining on the transmission case, and it is possible to reduce the manufacturing cost of the transmission case.

The low-pressure oil passage is provided below the penetrating portion of the high-pressure oil passage that guides the hydraulic oil having a higher pressure than the hydraulic oil flowing therethrough. The oil can be taken into the oil passage to prevent oil from leaking to the outside of the transmission case, and the leak oil can be used as low-pressure oil.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a drive system of a belt-type continuously variable transmission.

FIG. 2 is a circuit diagram showing a hydraulic control device of the continuously variable transmission shown in FIG.

FIG. 3 is a front view showing the main case shown in FIG. 1;

FIG. 4 is a front view showing the converter case shown in FIG. 1;

5A is a sectional view taken along line AA in FIG. 3, FIG. 5B is a sectional view taken along line BB in FIG. 4, and FIG. 5C is a sectional view taken along line CC in FIG. It is sectional drawing which follows a line.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Crankshaft 2 Torque converter 3 Forward / reverse switching mechanism 4 Continuously variable transmission main body 5 Lock-up clutch 7a Apply chamber 7b Release chamber 10 Transmission case 10a Converter case 10b Main case 10c Side case 11 Forward clutch 11a Clutch oil chamber 12 Reverse Brake 12a Brake oil chamber 13 Primary shaft 14 Secondary shaft 15 Primary pulley 16 Secondary pulley 17 Belt 23b Balance oil chamber 28b Balance oil chamber 31 Oil pump 54 Mating surface 55 Mating surface 56 Controller storage wall 57 Controller storage room 61 Clutch port 62 Lock-up Port 63 Release port 64 Low pressure port 65 Low pressure oil passage 66 Guide hole 67 Guide hole 68a, 68b Groove

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3J050 AA03 AB03 AB04 BA03 BB13 CE03 3J552 MA07 MA12 PA68

Claims (1)

[Claims] 1. A main case accommodating a transmission mechanism for transmitting the rotation of an input shaft to an output shaft by shifting the rotation, and a torque converter disposed between an engine and the transmission mechanism are accommodated and joined to the main case. And a converter case that constitutes a transmission case, and a high-pressure oil passage that guides hydraulic oil from a hydraulic oil storage portion provided in the transmission case to hydraulic equipment in the transmission case, the main case and the main case. A low-pressure oil passage formed through the mating surface with the converter case and guiding hydraulic oil from the hydraulic oil storage portion to a supplied portion in the transmission case, the mating surface between the main case and the converter case. An automatic transmission formed by a groove below a through portion of the high-pressure oil passage.