JPH036813Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a water pump for an internal combustion engine that supplies cooling water for cooling the internal combustion engine into the internal combustion engine.

Conventionally, this type of water pump has a pump chamber 2 formed in a pump body 11, as shown in FIG.
An impeller 4 fixed to a drive shaft 3 is provided, and the drive shaft 3 is rotatably supported by the pump body 11 via rolling bearings 15, 15. A mechanical seal 5 is provided between the pump body 11 and the impeller 4 to prevent leakage of cooling water. A drive gear 6 is provided at one end of the drive shaft 3.
The water pump is rotated by the power of the internal combustion engine as it meshes with gears of a drive system that drives auxiliary equipment such as a water pump installed inside the internal combustion engine. As a result, the rotation of the impeller 4 sends cooling water to the internal combustion engine. In the drive system including the drive gear 6, wear of the meshing parts is prevented by the lubricating oil accumulated in the oil pan and the lubricating oil flowing from a part of the lubricating oil path.

By the way, in this type of pump, when supporting the drive shaft 3 on the pump body 1, a rolling bearing 1 is used.
5 and 15, the disadvantage is that the water pump is long in the axial direction and large in the radial direction. For this reason, in order to mount the water pump inside the internal combustion engine and engage the drive gear 6 with the drive system of the internal combustion engine, the internal combustion engine also becomes larger. This cannot meet the demand for miniaturization of internal combustion engines. Although the mechanical seal 5 prevents cooling water from leaking from the pump chamber 2, sometimes the cooling water enters from the sliding surface of the mechanical seal 5 as water vapor, and this water vapor rolls into the bearings 15, 15. Special rolling bearings 1.
5 and 15 are generally used to improve durability. This results in increased manufacturing costs.

The present invention was devised in view of these points, and aims to provide a water pump for internal combustion engines that is compact by reducing the axial length and radial thickness, and is inexpensive without compromising durability. The purpose is to

The present invention will be described below based on embodiments shown in the accompanying drawings. 1 and 2 show an embodiment of the present invention, in which a drive shaft 3 is rotatably directly supported in a shaft hole 13 formed in a pump body 1. An oil seal 7 is provided between the pump body 1 and the drive shaft 3 behind the mechanical seal 5, and an annular hollow portion 8 is formed further behind the oil seal 7. A groove 9 is formed in the shaft hole 13 and extends from the annular cavity 8 to the end surface of the pump body 1. As the drive gear 6 rotates, lubricating oil is supplied to the groove 9 and flows out to the side surface of the gear, or is scattered around and transmitted along the outer circumferential surface of the pump body.
In order for natural inflow to take place, pump body 1
A notch 10 is formed in the upper end surface. A drain oil passage 12 for returning the lubricating oil accumulated in the annular hollow part 8 behind the oil seal 7 to the outside, for example, to an oil pan, is formed in the part of the pump body 1 facing the lubricating oil surface. As mentioned above,
During pump rotation, the lubricating oil supplied to the drive gear 6 flows out onto the side surface of the gear or scatters around the gear, and the lubricating oil leaked from the side surface of the gear or is scattered around the notch 10 between the end face of the pump body 1 and the drive gear 6. The lubricating oil scattered along the outer circumferential surface of the pump body flows into the groove 9, and the lubricating oil adhering to the drive shaft 3 is transferred to the sliding surface between the shaft hole 13 and the drive shaft 3 due to the rotation of the drive shaft. Since it is lubricated throughout, good sliding properties can be obtained. Then, the lubricating oil is transferred to the annular hollow part 8.
The lubricating oil flows into the drain oil passage 12 and returns to the oil pan, and the lubricating oil that flows in from the notch is transmitted through the groove 9 and the drive shaft 3 to form a circulation path with the drain oil passage 12, and actively cleans the sliding surface. Lubricating oil flows and lubricates.
Therefore, the drive shaft 3 can be moved without using rolling bearings.
can be rotatably supported. Since lubricating oil is also supplied to the sliding surface between the end face of the pump body 1 and the drive gear 6 through the notch 10, the end face of the pump body 1 and the drive gear 6 due to the thrust load caused by the spring force of the mechanical seal 5 are Prevents wear on sliding surfaces.

Incidentally, the shaft hole of the present invention may be formed by fitting a bush provided with a groove as necessary to the pump body.

Since the present invention is as described above, in a water pump for an internal combustion engine, the drive shaft can be supported on the pump body without using a rolling bearing, so the water pump can be made smaller and its manufacturing cost can be reduced. can be reduced.
Since lubricating oil is supplied to the shaft hole, there is an effect that the durability thereof is not impaired.

[Brief explanation of the drawing]

Figures 1 and 2 show an embodiment of the present invention.
Figure 1 is a longitudinal cross-sectional view of a water pump for an internal combustion engine, Figure 2 is a cross-sectional view taken along line A-A in Figure 1,
The figure is a longitudinal sectional view of a conventional water pump for an internal combustion engine. Explanation of symbols, 1, 11... Pump body, 2...
...Pump chamber, 3...Drive shaft, 4...Impeller, 5
...Mechanical seal, 6...Drive gear, 7...
...Oil seal, 8...Annular hollow part, 9...Groove,
10... Notch, 12... Drain oil path, 13...
Axial hole.

Claims (1)

[Scope of utility model registration request] A drive shaft 3 is rotatably supported on the pump body 1, an impeller 4 is provided at one end of the drive shaft 3 on the pump chamber 2 side, and a drive gear 6 that engages with a drive system inside the internal combustion engine is provided at the other end. In the water pump for an internal combustion engine that supplies cooling water to the internal combustion engine using power from the internal combustion engine, the drive shaft 3 is rotatably directly supported in the shaft hole 13 of the pump body 1, and the impeller 4 and the pump body 1 are connected to each other. An oil seal 7 is provided behind the mechanical seal 5 provided in between, and an annular hollow part 8 is formed further behind the oil seal 7, and extends from the annular hollow part 8 to the end surface of the pump body 1 in the shaft hole 13. In addition to forming the groove 9, a notch 10 is formed on the upper end surface of the pump body 1 to guide the lubricating oil supplied to the drive gear 6 to the groove 9, and an annular notch 10 is formed in the portion of the pump body 1 facing the lubricating oil surface. A water pump for an internal combustion engine, characterized in that a drain oil passage 12 is formed for discharging lubricating oil in a hollow part 8 to the outside.