JPH094454A - Water pump - Google Patents

Abstract

PURPOSE: To discharge cold water in a pump housing without splashing this to other parts such as a timing belt and the like by providing a draining mechanism loaded attachably/detachably being away from the back surface of an impeller for discharging the cold water in a direction back-facing the liquid sending direction of the impeller. CONSTITUTION: When a driving shaft 19 is driven by the rotation of an engine and an impeller 11 is rotated, cold water supplied from a cylinder head 3 through a pump sub-room 16a to a pump room 14 is approximately directly sent through a slope inner wall to a water supplying hole 14a. In this case, a drain plug 13 is fitted into an attaching hole provided in a pump housing 12 so as to seal a drain hole provided being communicated with the pump sub-room 16a in a side lower than the impeller 11, that is, in the lower part of the pump housing 12. In this position, cold water coming out of the drain plug 13 drops to the engine side and thus splashing of the cold water to a timing belt or a V belt is prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water pump mainly installed in a water-cooled internal combustion engine for automobiles.

[0002]

2. Description of the Related Art Conventionally, a water pump for circulating cooling water in a water jacket of a water-cooled engine may be disassembled and replaced with a defective part such as a mechanical seal when a problem occurs. In consideration of workability in such a case, one provided with a mechanism for draining cooling water is known. A water pump provided with such a mechanism for draining water is, for example, Japanese Patent Laid-Open No. 2-4100.
As in the publication No. 0, a pump cover that forms a pump chamber inside is fixed to the pump body, a pump impeller is rotatably mounted in the pump body, and a drain groove is provided below the pump impeller to It is known that a drain groove communicating with the pump chamber is communicated with a bolt hole for coupling with the pump cover to facilitate drainage of the cooling liquid in the pump chamber.

[0003]

As described above, in the device provided with the mechanism for draining the cooling water, such a drainage mechanism is not necessary in the normal operating state, It must be completely occluded. However, in the case where the drain groove is provided below the pump impeller, when the cooling water is circulated, that is, when the engine is operating, pressure is applied to the drain groove and the drain groove is tightened. However, the cooling water may leak due to aging. In other words, if a mechanism for draining water is provided at a position on the high-pressure side when the pump impeller operates, workability during maintenance work improves, but cooling water easily leaks during normal use and the leaked cooling water is If it scatters on the timing belt or the like, problems such as shortening their lifespan occur.

An object of the present invention is to eliminate such a problem.

[0005]

In order to achieve the above object, the present invention takes the following measures. That is, the water pump according to the present invention includes an impeller that sends cooling water to the cylinder block side, a pump housing that rotatably stores the impeller, and a pump housing that is separated from the back surface of the impeller in a direction opposite to the liquid feeding direction of the impeller. And a drain mechanism that is detachably attached to the lower part of the pump housing to discharge the cooling water.

[0006]

With this structure, the drain mechanism does not receive the pressure of the cooling water even when the impeller is rotating. That is, since the drain mechanism is installed at a position that is back to the liquid feeding direction of the impeller and is apart from the back surface of the impeller, when the impeller rotates, a negative pressure is applied to the cooling water around the drain mechanism. Will work. Therefore, the cooling water is depressurized with respect to the drain mechanism, and does not leak to the outside through the drain mechanism.
On the other hand, the cooling water is discharged in a fixed direction below the pump housing by operating the drain mechanism, and it is possible to effectively prevent the cooling water from being scattered to other parts.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

A water pump 1 shown in FIG. 1 is attached to a cylinder block 2 of a water-cooled engine for automobiles, and cooling water supplied from a radiator (not shown) to a water jacket of a cylinder head 3 is passed through a head cooling passage 3a. The liquid is sent to the cooling passage 2a of the cylinder block 2. In this embodiment, since the cylinder block 2 has a structure to which a conventional water pump can be attached, a pump chamber 14 described later is formed corresponding to the structure of the cylinder block 2, and cooling water from the pump chamber 14 is formed. It has a discharge amount adjusting plate 18 for adjusting the flow velocity, the flow rate, and the like. The cylinder block 2 is provided with a substantially circular water pump mounting recess 4 having a substantially rectangular water supply hole 4a communicating with a water jacket in the cylinder block 2 in the upper portion. This water pump mounting recess 4
Corresponds to the impeller position of a conventional water pump and functions as a part of its housing. A small diameter discharge hole 4b for discharging the cooling water in the cylinder block 2 to the pump chamber side is provided in the lower portion of the water pump mounting recess 4.

The water pump 1 includes an impeller 11 for sending cooling water flowing in from the cylinder head 3 side to the cylinder block 2 side, a pump housing 12 for rotatably housing the impeller 11, and a liquid feeding direction of the impeller 11. The drain plug 13 is detachably mounted on the pump housing 12 so as to be separated from the back surface of the impeller 11 in the back direction, and serves as a drain mechanism for discharging the cooling water.

The pump housing 12 includes a first body 16
The second body 17 and the second body 17 are connected by a bolt 6. The first body 16 has a pump sub chamber 16a for guiding the cooling water flowing from the head cooling passage 3a to the cylinder block 2.
Is formed, and the bearing 16b that rotatably supports the drive shaft 19 at the rear end portion is formed in the bearing chamber 16c.
It is attached to. Pump sub chamber 16a and bearing chamber 1
6c is a mechanical seal 16 that is detachably attached.
The water is stopped by d so that the cooling water does not flow into the bearing chamber 16c.

On the other hand, the second body 17 accommodates the impeller 11 and sends the cooling water flowing from the head cooling passage 3a to the cylinder block 2, and the pump chamber 1 and the pump chamber 1.
4 and a guide chamber 15 for guiding the cooling water discharged from the pump chamber 14 to the water supply hole 4a. The pump chamber 14 has a substantially circular shape slightly larger than the outer diameter of the impeller 11 and has an opening in front thereof. This opening is provided when the water pump 1 is attached to the cylinder block 2. It is occluded by two walls. With the impeller 11 housed in the pump chamber 14, the impeller 1 goes up from the lower side to the upper side of the impeller 11 via the position where the drain plug 13 is attached.
The impeller 11 is positioned in the pump chamber 14 such that the gap between the inner wall 14c of the pump chamber 14 and the inner wall 14c of the pump chamber 14 gradually increases (FIG. 2). The guide chamber 15 is provided obliquely above the pump chamber 14 so as to overlap the water pump mounting recess 4. Further, when the water pump 1 is attached, the guide chamber 15 overlaps the water pump mounting recess 4 and diffuses into the water pump mounting recess 4 before the supply hole 4
If the cooling water flows into the cylinder block 2, the cooling water cannot be delivered into the cylinder block 2 at a predetermined flow rate and flow rate. Therefore, the cooling water is substantially directly supplied by the fan-shaped discharge amount adjusting plate 18.
The water pump mounting recessed portion 4 is closed except for a part on the upper side so as to reach. Reference numeral 7 is a bolt for attaching the discharge amount adjusting plate 18.

The impeller 11 has a cylindrical portion 11a formed at the center thereof which is fitted to the drive shaft, and a blade portion 11b formed so as to surround the cylindrical portion 11a. When the drive shaft 19 is rotated, the impeller 11 sucks the cooling water in the pump subchamber 16a into its center and discharges the sucked cooling water in the circumferential direction. The cooling water is the inner wall of the pump chamber 14. It is guided by 14c and is discharged upward from the pump chamber 14 to the guide chamber 15. Therefore, the blade portion 11b has a shape slightly curved inward.

The drain plug 13 is provided in the pump housing 12 so as to close a drain hole 14d provided below the impeller 11, that is, in the lower part of the pump housing 12 and in communication with the sub-chamber 16a of the first body 16. It is screwed into the attached mounting hole 14e. In this position, when the water pump 1 is attached to the cylinder block 2, it is located on the extension of the side surface of the cylinder block 2 and the cooling water coming out of the drain plug 13 falls to the side of the engine. It is a thing.

When the water pump 1 is attached to the cylinder block 2, the discharge amount adjusting plate 18 closes almost the entire opening of the water pump attachment recess 4 except the water supply hole 4a. Further, the front side of the impeller 11, that is, the front side opening of the pump chamber 14 is closed by the cylinder block 2. In this way, the opening of the pump chamber 14 is closed, and the water pump mounting recess 4 is formed in the discharge amount adjusting plate 18.
The cooling water delivered from the pump chamber 14 is substantially directly supplied into the cylinder block 2 through the supply hole 4a. On the other hand, the drain port 4b is
It faces the discharge rate adjusting plate 18 with a slight gap, and due to the cooling water stored in the water pump mounting recess 4, although it is open, its function is almost completely prohibited. There is. That is, when the water pump 1 is operating, the cooling water is discharged from the drain port 4b, so that the water supply to the supply hole 4a is not hindered.

In the water pump 1 thus mounted, when the drive shaft 19 is driven by the rotation of the engine, the impeller 11 thereof rotates. When the impeller 11 rotates, the cylinder head 3 moves to the pump sub chamber 1
The cooling water flowing into the pump chamber 14 via 6a is sent to the water supply hole 4a substantially directly and via the inclined inner wall 15a of the guide chamber 15 as shown by the arrow in FIG. At this time, since the rotation of the impeller 11 is clockwise in FIG. 5, the water pressure of the cooling water becomes high on the guide chamber 15 side and becomes negative on the opposite side, that is, at the position where the drain plug 13 is attached. That is, the lower part of the pump sub chamber 16a where the drain hole 14d is opened is on the downstream side as seen from the movement of the cooling water, and the cooling water is drawn in by the rotation of the impeller 11, which is less than the state near the supply hole 4a. The negative pressure. Therefore, the cooling water flows into the cylinder block 2 at a predetermined flow rate and flow rate, and no water pressure is applied to the drain plug 13 through the drain hole 14d, which makes it difficult for the cooling water to leak in the operating state. .

On the other hand, when replacing the bearing 16b, the mechanical seal 16d and the cooling water, for example, if the drain plug 13 is loosened while the engine is stopped,
The cooling water stored in the pump sub chamber 16a is drained by the drain hole 14.
It flows out through d. When the cooling water level in the sub pump chamber 16a drops, the cooling water in the cylinder block 2 flows into the pump chamber 14 through the supply hole 4a and is discharged to the outside through the drain hole 14d. When the water is further discharged, the cooling water is drained through a drain hole 4 provided in the cylinder block 2.
5b flows into the water pump mounting recess 4,
From the above portion into the sub chamber 16a of the pump, and is discharged through the drain hole 14d. Drain plug 13 is cylinder block 2
Since it is attached to the side of the so as to project downward, the cooling water flowing out through the drain hole 14d is
When the drain plug 13 is removed, the drain plug 13 falls obliquely downward. Therefore, the cooling water does not hang on the timing belt or the V belt. Moreover, since the drain hole 4b is provided in the cylinder block 2, it is possible to drain the cooling water level in the cylinder block 2 to a low position,
The residual cooling water can be minimized when the cooling water is replaced.

The present invention is not limited to the embodiment described above.

In addition, the configuration of each section is not limited to the illustrated example, and various modifications can be made without departing from the spirit of the present invention.

[0019]

As described in detail above, according to the present invention, the cooling water can be discharged in a fixed direction below the pump housing by operating the drain mechanism. It is possible to effectively prevent the particles from scattering onto the V belt or the like. In addition, since the drain mechanism is installed at a position that is rearward in the liquid feeding direction of the impeller and is located at a position away from the back surface of the impeller, it is difficult to apply water pressure even when the cooling water is circulated, and the cooling water is not applied. Can be prevented from leaking to the outside through the drain mechanism.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a front view of the embodiment.

FIG. 3 is a rear view of the embodiment.

FIG. 4 is a bottom view of the embodiment.

FIG. 5 is an operation explanatory view showing the movement of the cooling water of the embodiment.

[Explanation of symbols]

 1 ... Water pump 2 ... Cylinder block 3 ... Cylinder head 11 ... Impeller 12 ... Pump housing 13 ... Drain plug 14d ... Drain hole

Claims (1)

[Claims] 1. An impeller for sending cooling water to a cylinder block side, a pump housing for rotatably housing the impeller, and a lower part of the pump housing spaced apart from an impeller rear surface in a direction opposite to a liquid feeding direction of the impeller. A water pump comprising: a drain mechanism that is detachably attached to discharge cooling water.