JP3751510B2 - Automatic transmission with auxiliary hydraulic unit - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention provides an auxiliary hydraulic unit that is provided to supply hydraulic pressure to a friction engagement element of an automatic transmission when the engine is temporarily stopped to avoid a shift shock or a time lag when the engine is restarted. The present invention relates to an automatic transmission with a hydraulic unit.
[0002]
[Prior art]
Recently, a system has been developed in which the engine is stopped when the vehicle is stopped to improve fuel efficiency and suppress carbon dioxide emissions.
[0003]
However, with such a configuration, in the case of a vehicle equipped with an automatic transmission, the oil pump driven by the engine stops when the engine stops, so the hydraulic pressure that has been supplied to the automatic transmission until then disappears. The operation of the frictional engagement elements such as the clutch and brake of the automatic transmission cannot be secured.
[0004]
In view of this, a method has been proposed in which an auxiliary hydraulic unit such as an electric oil pump is provided separately and the auxiliary hydraulic unit is driven to supply hydraulic pressure to the automatic transmission when the engine is stopped to ensure the operation of the friction engagement element. ing. This prevents the frictional engagement element from repeatedly releasing / engaging each time the vehicle stops / restarts, and prevents a shift shock or time lag from occurring each time.
[0005]
[Problems to be solved by the invention]
However, when an auxiliary hydraulic unit such as an electric oil pump is provided, it is difficult to arrange the unit in the automatic transmission because it is difficult to place the unit outside the automatic transmission. The arrangement of units is a big problem in terms of assembly and space, and no solution has been proposed yet. Further, even if the auxiliary hydraulic unit is arranged at an appropriate position, it is necessary to further connect the automatic transmission and the auxiliary hydraulic unit with a hydraulic circuit. However, a large number of hydraulic circuits are already arranged in the automatic transmission, and it is preferable to arrange a new hydraulic circuit because it causes a significant design change of the automatic transmission and an increase in processing man-hours. Absent.
[0006]
In view of the circumstances described above, the present invention can not only arrange an auxiliary hydraulic unit such as an electric oil pump at an advantageous position in terms of assembly and space, but also provide a hydraulic circuit between the auxiliary hydraulic unit and the automatic transmission. It is an object of the present invention to provide an automatic transmission with an auxiliary hydraulic unit that can be connected with a configuration as simple as possible.
[0007]
[Means for Solving the Problems]
The present invention includes an auxiliary hydraulic unit (12) capable of supplying hydraulic pressure to an oil passage (29) inside the automatic transmission in addition to the hydraulic pressure supplied from an oil pump (21) driven by the engine. In the automatic transmission (1) with an auxiliary hydraulic unit provided,
The auxiliary hydraulic unit is mounted on the outer periphery of the automatic transmission case (2),
A connecting oil passage (13, 15, 16, 17) is provided between the auxiliary hydraulic unit and the oil passage inside the automatic transmission.
[0010]
A branch conduit (16) is formed in the oil passage for connection between the auxiliary hydraulic unit and the oil passage inside the automatic transmission from the oil pump inside the automatic transmission formed in the case. An oil passage (17) communicating with an oil passage to which hydraulic pressure is supplied and penetrating the case is connected to a discharge port of the auxiliary hydraulic unit;
The branch pipe has a first oil passage (16b) connected to an oil passage (17) penetrating the case, and a clutch oil pressure detection auxiliary oil passage (16c) is connected to the first oil passage. And an auxiliary hydraulic unit connecting oil passage (16e).
[0011]
According to a second aspect of the present invention, the auxiliary hydraulic unit is mounted on the outer peripheral portion of the case corresponding to the position where the torque converter (6) is housed.
According to a third aspect of the present invention, there is provided the automatic transmission in the connecting oil passage (13, 15, 16, 17) between the auxiliary hydraulic unit (12) and the oil passage (29) inside the automatic transmission. A check valve (16d) is provided for preventing hydraulic fluid from the side from flowing toward the auxiliary hydraulic unit.
[0013]
According to a fourth aspect of the present invention, in the third aspect of the present invention, hydraulic oil is supplied from the first oil passage to the auxiliary hydraulic unit (12) in the auxiliary hydraulic unit connecting oil passage (16e) of the branch pipe (16). ) constructed by the check valve (16d) is provided to prevent flow toward the side.
[0014]
According to a fifth aspect of the present invention, in the first aspect of the present invention, the oil passage penetrating the case is constituted by a clutch pressure detecting oil passage (17).
[0015]
【The invention's effect】
According to the invention of claim 1, since the auxiliary hydraulic unit (12) is mounted on the outer peripheral portion of the case (2) of the automatic transmission (1), the automatic transmission and the auxiliary hydraulic unit can be handled as a unit. As in the case of conventional automatic transmissions, the auxiliary hydraulic unit can be easily installed without extra work such as mounting the vehicle on the vehicle body.
Further, the connecting oil passage can be formed by using the oil passage (17) penetrating the case provided in the automatic transmission (1) by the branch pipe (16).
[0016]
According to the invention of claim 2, since the auxiliary hydraulic unit (12) is mounted on the outer peripheral portion corresponding to the position where the torque converter (6) is stored, the automatic transmission mechanism (3) is stored. It is no longer necessary to perform processing for mounting the auxiliary hydraulic unit on the central main part of the transmission (1), which can contribute to the common use of main parts.
[0019]
According to the invention of claim 3 , the check valve (16d) prevents hydraulic hydraulic oil generated by the oil pump (21) driven during engine rotation from flowing into the auxiliary hydraulic unit and being drained. I can do it.
[0021]
According to the invention of claim 4 , since the check valve (16d) is provided in the branch pipe (16), it is not necessary to provide a check valve in the multi-stage transmission mechanism (3) portion, and the auxiliary hydraulic pressure with a simple configuration is provided. An automatic transmission with a unit can be provided.
[0022]
According to the invention of claim 5 , the connecting oil passage is formed by using the clutch pressure detecting oil passage (17) originally provided in the automatic transmission (1) by the branch pipe (16). Therefore, it is not necessary to form a new oil passage inside the automatic transmission, and it is possible to prevent the internal structure of the automatic transmission from becoming complicated and increasing the number of processing steps.
[0023]
Note that the numbers in parentheses are for the sake of convenience indicating the corresponding elements in the drawings, and therefore the present description is not limited to the descriptions on the drawings.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a circuit diagram illustrating an example of a main part of a hydraulic circuit of an automatic transmission in which an auxiliary hydraulic unit is disposed. FIG. 2 is a front view showing an auxiliary hydraulic unit mounted in front of the case. FIG. 3 is a side view of FIG. 4 is a bottom view of FIG. FIG. 5 is a cross-sectional view showing an example of a branch pipe. FIG. 6 is a cross-sectional view showing an example of an automatic transmission to which the present invention is applied. FIG. 7 is an external view of the automatic transmission of FIG.
[0025]
As shown in FIG. 6, the automatic transmission 1 has a housing 2 that covers a torque converter 6 to be described later, a transmission case that covers a multistage transmission mechanism 3, and a case 2 that includes an extension portion 2b in which an output shaft 11 is disposed. The case 2 is provided with a torque converter 6 having a multi-stage transmission mechanism 3 and a lock-up clutch 5 stored therein. The multi-stage transmission mechanism 3 includes, from the torque converter 6 side, an overdrive unit 7 including a C0 clutch and a simple planetary gear, which will be described later, a main transmission unit 9 including a Simpson type planetary gear unit 9a and a single planetary gear 9b. Has been placed. The automatic transmission 1 shifts the rotation of the input shaft 10 from the fifth forward speed to the first reverse speed and outputs it to the output shaft 11.
[0026]
As shown in FIG. 7, in the automatic transmission 1, an electric oil pump 12, which is an auxiliary hydraulic unit, is mounted on the lower side of the outer peripheral portion of the case 2 corresponding to the position where the torque converter 6 is housed. . As shown in FIGS. 2 to 4, the electric oil pump 12 includes an electric motor 12d and a pump 12e that is rotationally driven by the electric motor 12d. The electric oil pump 12 in the assembled state is It is fixed to the case 2 via a bracket 12a. The pump 12e of the electric oil pump 12 has a suction port 12b and a discharge port 12c. One end of a pipe 13 is connected to the suction port 12b, the other end of the pipe 13 is connected to an oil pan 2a provided in the lower part of the case 2, and one end of a pipe 15 is connected to the discharge port 12c. The other end of the pipe 15 is connected to a clutch pressure detecting oil passage 17 opened in the case 2 of the automatic transmission 1 through a branch pipe 16.
[0027]
As shown in FIG. 5, the branch line 16 has a main body 16a formed in a substantially L shape, and the main body 16a is connected to the above-described clutch pressure detection oil path 17 by screwing. A connecting pipe line 16b is formed. The upper end of the transmission connection line 16b in the figure is bifurcated, one of which is formed with a clutch pressure detection line 16c, and the clutch pressure detection line 16c has a free end, which will be described later with reference to FIG. A pressure gauge 19 for measuring the clutch pressure can be connected. The pressure gauge 19 is not connected in the normal use state of the automatic transmission 1, and the clutch pressure detection conduit 16c is closed by a cap nut 16f or the like. When measuring the hydraulic pressure of hydraulic oil supplied to the C0 clutch disposed in the overdrive unit 7 during assembly or maintenance of the automatic transmission 1, the pressure nut 19 is connected and used by removing the cap nut 16f. The
[0028]
An electric oil pump connection line 16e is formed on the other side of the mission connection line 16b together with a check valve 16d provided in the middle of the transmission line 16b. The pipe 15 is connected to the electric oil pump connection line 16e. ing.
[0029]
FIG. 1 schematically shows a hydraulic circuit between the electric oil pump 12 and the automatic transmission 1. A primary regulator valve 22, a manual valve 23, and a pressure control valve 25 are connected to an oil pump 21 that is connected from the oil pan 2 a through a strainer 20 and is driven to rotate by an engine (not shown). Further, a C1 clutch is connected as a friction engagement element that is always kept in an engaged state when the automatic transmission 1 is in the forward state.
[0030]
In addition, an overdrive C0 clutch is connected to the pressure control valve 25 through a shift valve 26 together with an accumulator 27. An oil passage 29 between the shift valve 26 and the C0 clutch is connected to the aforementioned branch pipe. The passage 16 is connected via a clutch pressure detection oil passage 17 that is branched in the middle of the oil passage 29 and is an oil passage penetrating the case 2. As described above, the pressure gauge 19 can be connected to the branch line 16 via the clutch pressure detection line 16c, and the electric oil pump 12 is connected to the branch line 16 via the electric oil pump connection line 16e. Yes. A strainer 20 provided in the oil pan 2 a is connected to the electric oil pump 12 via a pipe 13.
[0031]
Since the automatic transmission 1 and the like have the above-described configuration, when the vehicle moves forward, that is, when the engine is driven, the oil pump 21 is rotationally driven, so that the hydraulic pressure generated by the oil pump 21 is a line. The pressure is supplied to the primary regulator valve 22, the manual valve 23, the pressure control valve 25, and the like, and further supplied to the C0 clutch via the C1 clutch and the shift valve 26. By this line pressure, the C1 clutch and the C0 clutch are appropriately engaged and driven, and the automatic transmission 1 can perform a normal shift operation. At this time, the line pressure from the oil pump 21 also acts on the branch line 16 via the oil path 29 and the clutch pressure detection oil path 17, but the hydraulic pressure acting on the branch line 16 is used for clutch pressure detection. The pipe line 16c portion is sealed with a cap nut 16f, and the electric oil pump connection pipe line 16e is prevented from being transmitted to the hydraulic oil to the electric oil pump 12 side by the check valve 16d. The occurrence of a situation in which the hydraulic oil flows into the electric oil pump 12 and leaks is prevented.
[0032]
Next, when the engine stops driving when the vehicle stops, the driving of the oil pump 21 that has been rotationally driven by the engine is stopped, and the line pressure generated by the oil pump 21 decreases, and C1 Naturally, the hydraulic pressure supplied to the clutch and the C0 clutch also decreases, and when no processing is performed, the hydraulic pressure of the C1 clutch or the C0 clutch that has been engaged at the time of forward movement is drained, and the clutch is released. However, at the same time as the engine is stopped, the electric oil pump 12 starts to rotate, and the electric oil pump 12 sucks the oil in the oil pan 2a through the strainer 20 and the pipe 13, and the pipe 15 at a predetermined pressure. To the electric oil pump connection pipe 16e of the branch pipe 16.
[0033]
The oil supplied to the electric oil pump connection line 16e flows into the mission connection line 16b side where the oil pressure has decreased due to the stop of the oil pump 21 via the check valve 16d, and further detects the clutch pressure of the case 2. It is supplied from the oil passage 17 to the oil passage 29. As a result, a low-pressure frictional engagement element holding pressure is supplied from the electric oil pump 12 through the oil passage 29, and the frictional engagement element holding pressure causes the C0 clutch and the C1 clutch to loosen immediately before engagement. It will be held in a packed state.
[0034]
In this state, when the engine is started again and the vehicle starts moving forward, the oil pump 21 is restarted to rotate by the engine, the line pressure generated by the oil pump 21 is supplied to the automatic transmission 1, and the C0 clutch and These line pressures are also supplied to friction engagement elements such as the C1 clutch, and the automatic transmission 1 starts a shift operation. Since the friction engagement element holding pressure is supplied to the C0 clutch and the C1 clutch by the electric oil pump 12 even when the engine is stopped, the C0 clutch and the C1 clutch are immediately loose when the line pressure is supplied when the engine is restarted. The engagement operation is performed in a manner that prevents the occurrence of a shift shock in a short time and as much as possible, and effectively prevents the driver from feeling uncomfortable when starting the vehicle operation. .
[0035]
Even when the electric oil pump 12 is still mounted, if it is necessary to measure the hydraulic pressure supplied to the C0 clutch during maintenance, the pressure gauge 19 is connected to the clutch pressure detection line 16c of the branch line 16. In addition, the oil pressure can be measured smoothly by removing and attaching the cap nut 16f.
[0036]
In the above-described embodiment, the case where the electric oil pump 12 is mounted on the outer peripheral lower surface of the case 2 on the torque converter 6 side has been described, but the electric oil pump 12 may be mounted anywhere as long as it is mounted on the case 2. . For example, it is also possible to mount the lower portion of the extension portion 2b of the rear output shaft 11 are arranged than the housing central portion multistage transmission mechanism 3 of automatic transmission 1 is housed. Since the extension 2b portion of the case 2 has a smaller diameter than the other portions of the case 2, the electric oil pump 12 can be easily attached.
[Brief description of the drawings]
FIG. 1 is a circuit diagram showing an example of a main part of a hydraulic circuit of an automatic transmission in which an auxiliary hydraulic unit is arranged.
FIG. 2 is a front view showing an auxiliary hydraulic unit mounted in front of the case.
FIG. 3 is a side view of FIG. 2;
4 is a bottom view of FIG. 2. FIG.
FIG. 5 is a cross-sectional view showing an example of a branch pipe.
FIG. 6 is a cross-sectional view showing an example of an automatic transmission to which the present invention is applied.
7 is an external view of the automatic transmission of FIG. 6. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Automatic transmission 2b ... Extension 16d ... Check valve 6 ... Torque converter 12 ... Auxiliary hydraulic unit 12b ... Suction port 13, 15 ... Connection oil path (pipe)
16 …… Oil channel for connection (branch pipeline)
16b ...... First oil passage (mission connection pipe)
16c: Clutch pressure detection auxiliary oil passage (clutch pressure detection pipe)
16e …… Auxiliary hydraulic unit connection oil passage (electric oil pump connection pipeline)
17 …… Oil passage for connection, oil passage through the case (clutch pressure detection oil passage)
29 …… Oil passage inside the automatic transmission (oil passage)

Claims (5)

In the automatic transmission with an auxiliary hydraulic unit provided with an auxiliary hydraulic unit capable of supplying hydraulic pressure to the oil passage inside the automatic transmission in addition to the hydraulic pressure supplied from the oil pump driven by the engine,
The auxiliary hydraulic unit is attached to the outer peripheral portion of the case of the automatic transmission,
A connecting oil passage is provided between the auxiliary hydraulic unit and the oil passage inside the automatic transmission,
A branch conduit is formed in the oil passage for connection between the auxiliary hydraulic unit and the oil passage inside the automatic transmission, and the oil pressure from the oil pump inside the automatic transmission is supplied to the case. An oil passage that communicates with an oil passage and is connected to an oil passage that penetrates the case and a discharge port of the auxiliary hydraulic unit,
The branch pipe has a first oil passage connected to an oil passage penetrating the case, and a clutch oil pressure detection auxiliary oil passage and an auxiliary hydraulic unit connection oil passage are provided in the first oil passage. An automatic transmission with an auxiliary hydraulic unit , formed in a connected form .   The automatic transmission with an auxiliary hydraulic unit according to claim 1, wherein the auxiliary hydraulic unit is configured to be mounted on an outer peripheral portion of a case corresponding to a position where a torque converter is accommodated.   A check valve that prevents hydraulic oil from the automatic transmission side from flowing toward the auxiliary hydraulic unit side in a connecting oil path between the auxiliary hydraulic unit and an oil path inside the automatic transmission. The automatic transmission with an auxiliary hydraulic unit according to claim 1, wherein: Wherein the branch line oil passage for the auxiliary hydraulic unit connection, the check valve the hydraulic oil is prevented from flowing toward the auxiliary hydraulic unit side from the first oil passage is provided, according to claim 3 Automatic transmission with auxiliary hydraulic unit as described. Oil passage is an oil passage for exiting clutch pressure, the auxiliary hydraulic unit with an automatic transmission according to claim 1, wherein extending through the case.

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