JP2528322Y2 - Oil circulation structure for automatic transmission - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an improvement of an automatic transmission for a vehicle.

[0002]

2. Description of the Related Art Conventionally, in an automatic transmission for an automobile, oil circulating inside is sent from an oil pump, but oil drained from a regulator valve of a control valve flows down into a lower oil pan, and the oil pan The oil is returned to the oil pump again through the strainer arranged in the inside, but when all the oil passes through the strainer and enters the oil pump, the suction negative pressure of the oil pump becomes large, and the oil pump operates. Since the power increases and the power efficiency and the oil pump noise deteriorate, a structure is employed in which the oil is directly returned to the suction circuit of the oil pump without passing through the oil strainer.

[0003]

However, there is a problem that it is difficult to form a circuit for returning oil and that the circuit complicates the structure.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and provides a circulation structure of an automatic transmission that can reduce the suction negative pressure of an oil pump with a simple structure. The gist of the invention is that an oil pump housed in a housing is provided in a case, and an oil pan having an oil strainer is provided on the lower surface of the case, and the oil pump is provided at an upper portion in the case. In an automatic transmission having a control valve for controlling a flow of oil to be sent, an oil that has passed through the control valve without passing through the oil strainer between the case and the housing of the oil pump. That is, a drain groove is formed to flow directly into the nozzle.

[0005]

[Action] A drain groove is formed between the case constituting the automatic transmission and the housing containing the oil pump, and the oil flowing downward through the upper control valve through the drain groove is directly injected into the oil pump. Since all of the oil flowing down can not pass through the oil strainer, the negative suction pressure of the oil pump is reduced, and the power efficiency and the oil pump noise are improved.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view of the oil pump, and FIG.
2 shows a cross-sectional view taken along line AA in the schematic cross-sectional view of the automatic transmission shown in FIG.

In the figure, an automatic transmission 1
Is covered with a case 2, a torque converter 3 is provided in the case 2, and the output of the engine is transmitted to the input shaft 4 through the torque converter 3. An oil pump 6 rotated by the shaft 4 is provided in the case 2, and the oil pump 6 is housed in an oil pump housing 5.

That is, the oil pump 6 comprises an inner gear 6a housed in the oil pump housing 5 and an outer gear 6b outside the inner gear 6a. The inner gear 6a is rotated by the input shaft 4 to form an outer gear. The gear 6b also rotates, and at this time, when the narrow portion between the gears 6a and 6b is rotated, the gap between the gears 6a and 6b is widened, a negative pressure is generated, and the oil from the suction port 6c of the oil pump 6 And the oil can be sent to the discharge port 6d side.

A gear chamber S accommodating a clutch and gears is formed in the center of the case 2, and an oil pan 7 is provided on the lower surface side of the case 2, and an oil strainer is provided inside the oil pan 7. The oil strainer 8 is provided with an oil chamber O formed by an oil pan 7.
It is immersed in oil that accumulates inside. The oil strainer 8 communicates with the suction port 6c of the oil pump 6 via an oil passage.

A control valve 9 having a regulator valve 9a is provided at an upper portion of the case 2, and the control valve 9 controls opening / closing and control of oil sent from an oil pump 6, thereby providing the gear chamber. Oil is supplied to gears and the like housed in the S to circulate the oil.

In this embodiment, as shown in FIG. 1, a drain groove 10 is formed between the oil pump housing 5 accommodating the oil pump 6 and the case 2, and an upper end of the drain groove 10 is provided with the regulator. The lower end of the drain groove 10 is connected to the suction port 6 c of the oil pump 6 above the strainer 8.

In such a configuration, the oil sent upward by the operation of the oil pump 6 is supplied to the gear chamber S through the control valve 9 and passes through the strainer 8 through the drain groove 10 from the regulator valve 9a. The oil is directly returned into the suction port 6c of the oil pump 6, and therefore all the oil does not pass through the strainer 8, so that the suction negative pressure is favorably reduced by the oil flowing directly into the suction port 6c through the drain groove 10. The operating power of the oil pump 6 is reduced, and the power efficiency and the oil pump noise are improved satisfactorily.

Since the oil that flows directly into the oil pump 6 through the drain groove 10 passes through the strainer 8 once, it does not affect the lubricating performance as much as the difference, and a part of the oil passes through the strainer 8. Since the oil is injected into the oil pump 6, there is no effect on the entry of foreign matter into the oil.

[0014]

According to the present invention, an oil pump housed in a housing is provided in a case, an oil pan having an oil strainer is provided on a lower surface of the case, and the oil pump is delivered from the oil pump to an upper portion in the case. In an automatic transmission having a control valve for controlling the flow of oil to be supplied, the oil that has passed through the control valve without passing through the oil strainer is supplied to the suction port of the oil pump between the case and the housing of the oil pump. By forming a drain groove for direct inflow, a drain groove can be easily formed between the housing and the case, and oil can be directly injected into the oil pump through this drain groove. Without passing the oil pump Narrowing have negative pressure is reduced, and improved operating efficiency of the oil pump, also has an effect capable of reducing the oil pump noise.

[Brief description of the drawings]

FIG. 1 is a sectional view taken along the line AA of FIG. 2;

FIG. 2 is a schematic sectional side view of an automatic transmission.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Automatic transmission 2 Case 4 Input shaft 5 Housing 6 Oil pump 7 Oil pan 8 Strainer 9 Control valve 10 Drain groove

Claims (1)

(57) [Scope of request for utility model registration] An oil pump housed in a housing is provided in a case, an oil pan having an oil strainer is provided on a lower surface of the case, and an oil pump delivered from the oil pump is provided at an upper portion in the case. In an automatic transmission having a control valve for controlling a flow, a drain is provided between the case and the housing of the oil pump, the oil having passed through the control valve flowing directly into the suction port of the oil pump without passing through the oil strainer. The oil circulation structure of the automatic transmission, characterized by forming grooves.