JPH033911A - Oil pump for engine with transmission - Google Patents

Abstract

PURPOSE:To simplify the structure of an oil pump and reduce the axial size by fixing a pump cover surrounding a rotor on the side face of a bearing holder. CONSTITUTION:A bearing holder 6 supporting one end of the rotary shaft of a transmission 3 is assembled near a main clutch 13 in a transmission case 4 integral with an engine E. The inner rotor 23 of an oil pump 20 is freely coupled with a main shaft 8 while its one side face is kept in contact with the side face 21 of the main clutch 13 side of the bearing holder 6, and it is fixed to a sleeve 26 rotated by the coupling between the coupling section 25a of a driven gear 14 and a coupling section 25. A pump cover 22 surrounding the peripheries of the inner rotor 23 and an outer rotor 24 and the variable- volume section on the other side face is fixed to the bearing holder 6. The side face of the bearing holder 6 is utilized as one side face of a pump chamber, thus the axial size of the oil pump 20 can be formed small.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an oil pump for an engine, such as a motorcycle engine, in which a transmission is integrated with the engine and the entire oil pump is required to be compact.

(Prior Art) An oil pump that supplies oil to various parts of an engine and transmission usually has a drive shaft dedicated to the oil pump and is supported within the crankcase or transmission. Since the crankcase or transmission becomes larger, in order to improve this, the applicant proposed
As shown in No. 31811, a rotor chamber is provided protruding from the side surface of a bulkhead on which a bearing supporting one end of a rotating shaft of a transmission is attached, a trochoid rotor of the pump is attached to the main shaft of the transmission passing through the pump chamber, and the rotor He proposed an invention in which the chamber was covered with a pump cover.

(Problems to be Solved by the Invention) The partition wall in the above-mentioned invention has the disadvantage that the structure becomes complicated because the pump rotor chamber, inlet channel, outlet channel, etc. must be formed outside the bearing mounting portion. .

Therefore, an object of the present invention is to further develop the advantages of the above-mentioned invention to obtain an oil pump that has a simple structure, a small axial dimension, and is useful for downsizing an engine.

(Means for Solving the Problems) The object of the present invention is to assemble a bearing holder close to the main clutch inside a transmission case integrated with an engine, and to use the bearing holder at one end of the rotating shaft of the transmission. In an engine with a transmission that supports the bearing holder, an oil pump rotor is loosely fitted onto the main shaft of the transmission with one side in contact with the main clutch side side of the bearing holder, and a variable volume portion on the circumferential surface of the rotor and the other side. A pump cover surrounding the pump cover is fixed to a bearing holder, and an inner peripheral portion of the rotor is connected to an input member of a main clutch. Mounting thinner than the cover is solved by a second solution with the addition of a feature characterized by the provision of a flange.

(Function) By the above means, one side surface of the rotor comes into sliding contact with the side surface of the bearing holder, and the peripheral surface and the other side surface come into sliding contact with the inner surface of the rotor chamber of the pump cover. When installing the pump cover, the flange is lower than the inflow and outflow passages provided on the pump cover, so the bolt heads do not protrude during installation, and the axial length of the pump is substantially equal to the rotor width and outflow. The height is the sum of the height of the outer wall of the channel or inflow channel, and the dimensions are small. On the other hand, since the bearing holder can be a substantially flat plate, its axial dimension can be small, resulting in a smaller pump.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings. 1st
In the figure, l is the crankcase of the engine E, which supports the crankshaft 2 and is part of the case 4 of the transmission 3.
form. A step part 5 is formed at one end of the case 4, and a partition-like bearing holder 6 is fixed with a bolt. Bearings or roller bearings are attached to support rotating shafts such as the main shaft 8 and the counter shaft 9.

A transmission gear group g1G is provided on both shafts 8.9, and output is taken out from a sprocket 10 and a chino 11.

The rotation of the crankshaft 2 is transmitted from the drive gear 12 to the main clutch 1.
A friction plate group 15 that is transmitted to the driven gear 14 of No. 3 and can be freely moved toward and away from the
The signal is transmitted from the hub IB to the main shaft 8 via. Main clutch 1
3 is closed with a cover 17.

The oil pump 20 is a commonly used trochoid type pump, and is provided between the bearing holder 6 and the driven gear I4. The pump 20 includes a rotor chamber formed by a side surface 21 of a bearing holder 6 and a recess provided inside a pump cover 22, and an inner rotor 23 and an outer rotor 24 are enclosed in the rotor chamber to define a peripheral surface and a variable volume portion. The inner rotor 23 is surrounded by a sleeve 2B that is loosely fitted onto the main shaft 8 and is rotated by engaging with the driven gear 14 at an engaging portion 25a and an engaging portion 25.
It is fixed to the engine and rotates constantly when the engine is running.

The pump cover 22 has outer walls of a suction passage 27 and a discharge passage bulged on the side surface, and a mounting flange 29 is provided around the periphery and is fixed to the bearing holder 6 with bolts 30. The flange 29
is formed thin so that the head of the bolt 80 does not protrude from the side surface 22 of the cover.

Further, a suction passage 27 is formed on the side surface 21 of the bearing holder 6 as a concave surface facing the suction passage 27 and the discharge passage 28.
An a1 discharge passage 28a is dug to facilitate oil inflow and outflow, and a relief valve communicating with this discharge passage 28a is provided in the bearing holder 6.

As shown in FIG. 2, the relief valve 3 is attached to the bearing holder 6.
One valve chamber 32 is bored, an inlet 34 communicating with the valve seat 33 and the discharge passage 28a is provided at the tip thereof, and an outlet 35, 36 communicating with the suction passage 27 is provided on the side. Then, a stepped cylindrical piston valve 37 is inserted into the valve chamber 32,
It is pressurized toward the valve seat 33 by a spring 38 and a push screw 39.

Therefore, when the oil pressure in the discharge passage 28 becomes excessive, the piston valve 37 retreats and oil flows into the inflow passage 27 from the inlet 34 and the outlet 35, and when the appropriate pressure is reached, the valve seat 33 is closed. Oil leaking from the outer circumference of the piston valve 37 is transferred to the outlet 3.
6 into the inflow path 27.

As described above, when the engine starts, the rotor 23.2 of the oil pump 20 is connected to the drive gear 12, the driven gear 14 of the main clutch 13, the engaging portion 25a125, and the sleeve 26.
4 is rotated and oil is drawn into the suction passage 27.2 from a passage not shown.
The oil is sucked into the engine 7a and delivered to each part of the engine through the discharge passages 28 and 28a, and the transmission 3 is sprayed with oil through the oil supply pipe 40.

When the oil pressure becomes excessive, oil is discharged from the relief valve 31.

(Effects of the Invention) In the oil pump described above, the side surface of the bearing holder is used as one side surface of the pump chamber, and the oil pump is formed by fixing the pump cover surrounding the inner rotor and the outer rotor to this side surface. The axial dimension of the pump can be made extremely small, and the oil pump can be installed without changing the length of the main shaft including the main clutch. Therefore, compared to the conventional technology in which an oil pump is provided independently in the crankcase or transmission, there is no need to provide the oil pump and a transmission mechanism to drive it, so the volume of the crankcase, etc. can be reduced. , the engine can be made smaller, and the structure of the bearing holder is simple and the number of parts is small, so it can be constructed at low cost.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of an embodiment of the present invention, and FIG. 2 is a sectional view taken along the line ■--■ in FIG. 3...Transmission 6...Bearing holder 13...
・Main clutch 20...Oil pump 23.24
...Rotor 29...3 people outside the flange

Claims (1)

[Scope of Claims] 1. In an engine with a transmission, in which a bearing holder is assembled close to the main clutch inside a transmission case integrated with the engine, and the bearing holder supports one end of the rotating shaft of the transmission. , a rotor of an oil pump is loosely fitted onto the main shaft of the transmission with one side in contact with the side surface on the main clutch side of the bearing holder, and a pump cover surrounding the circumferential surface of the rotor and the variable volume portion on the other side is attached to the bearing holder. An oil pump for an engine with a transmission, characterized in that the oil pump is fixed and the inner peripheral part of the rotor is connected to an input member of a main clutch. 2. The oil pump for an engine with a transmission according to claim 1, characterized in that a mounting flange that is thinner than the pump cover is provided around the pump cover.