JP5076998B2 - Water pump - Google Patents

Description

  The present invention mainly relates to a water pump used for circulating cooling water of a water-cooled engine.

  In the water pump that operates the power of the water-cooled engine via a timing chain or a timing belt, a mechanical seal is provided between the impeller and the bearing in order to prevent cooling water from leaking outside the water pump. However, the vapor-shaped cooling water leaks out from the seal portion of the mechanical seal.

Therefore, in Patent Document 1, the cooling water leaking from the seal portion of the mechanical seal is discharged to the outside by a discharge passage (drain discharge port, drain hole) formed in the body of the water pump, and the lower portion of the opening of the discharge passage A water pump is disclosed in which a draining part is provided to suppress the leaked coolant from being transmitted through the body.
Japanese Utility Model Publication No. 3-56899

  However, in the configuration of Patent Document 1, it is not possible to suppress the leakage of the coolant that has leaked out to the outside of the water pump only by suppressing the leakage of the coolant.

  This invention is made | formed in view of said subject, The objective makes it a technical subject to provide the water pump which can suppress that the leaked cooling water flows out of the outside of a water pump. .

In order to solve the above technical problem, the first technical means taken in the present invention is:
An impeller provided at one end of a rotating shaft supported by a body via a bearing;
A mechanical seal provided between the impeller and the bearing;
A drain hole formed below the body and discharging water droplets leaked from the impeller side through the mechanical seal to the outside of the body;
A drive pulley for rotating the impeller via the rotating shaft,
The water pump is characterized in that a groove extending in the circumferential direction of the drain hole is formed in the inner periphery of the drain hole while the axial section of the rotating shaft forms a plurality of V shapes.

The second technical means is the first technical means,
In the groove, the axial section of the rotating shaft has a sawtooth shape.

The third technical means is the first technical means or the second technical means,
The groove is formed in a spiral shape on the inner periphery of the drain hole.

The fourth technical means is the first technical means or the second technical means,
The groove is formed at least on the lower side of the inner periphery of the drain hole.

  According to the first aspect of the present invention, the leakage leaked by forming the grooves extending in the circumferential direction of the drain hole while forming the plurality of V-shaped axial cross sections of the rotating shaft on the inner periphery of the drain hole. When water tries to flow through the drain hole, it enters the groove. Since the groove is V-shaped, it becomes narrower as it goes to the bottom of the groove. Therefore, the leaked cooling water travels in the direction of the opening of the drain hole and the direction of the bottom so as to follow the inner periphery of the drain hole by capillary action. As a result, it takes time until the leaked cooling water flows out of the water pump, and during that time, it is possible to obtain time for drying, and the amount of cooling water flowing out of the water pump can be suppressed.

  According to the second aspect of the present invention, the grooves can be formed in the inner periphery of the drain hole by forming a sawtooth shape in the axial section of the rotating shaft.

  According to the invention of claim 3, since the groove is spirally formed on the inner periphery of the drain hole, when the leaked cooling water is transmitted through the groove by capillary action, the groove is spirally transmitted along the inner periphery of the drain hole. . When there is no groove, the leaked cooling water flows linearly through the inside of the drain hole toward the opening. Therefore, by providing a spiral groove on the inner periphery of the drain hole, You can lengthen the length.

  According to the invention of claim 4, since the groove is formed at least on the lower side of the inner periphery of the drain hole, when the leaked cooling water tries to flow through the drain hole, the groove acts as a flow path resistance. It becomes difficult. Therefore, it takes time until it flows out of the water pump, and it is possible to obtain time for drying the leaked cooling water during that time, and the amount of cooling water flowing out of the water pump can be suppressed.

  Hereinafter, a first embodiment of the present invention will be described with reference to FIG.

  The body 10 is fixed to the cylinder block 11 with bolts or the like, and a rotating shaft 13 is supported on the body 10 via a bearing 12. A driving pulley 15 is fixed to one end of the rotating shaft 13 by a bolt or the like via a pulley bracket 14, and an impeller 16 is fixed to the other end by press-fitting. The rotating shaft 13 and the impeller 16 are rotated by the rotation of the driving pulley 15. To do. An annular mechanical seal 17 is disposed between the impeller 16 and the bearing 12. However, the cooling water flowing on the impeller 16 side passes through the seal portion 17 a of the mechanical seal 17 and leaks so as to ooze out into the space 18.

  The body 10 has a vapor drain 20 for allowing the vapor-shaped cooling water out of the leaked cooling water to escape obliquely upward, a vapor hole 21 for communicating with the vapor drain 20 and allowing the water to escape to the atmosphere, and the droplet-shaped cooling water. A drain discharge port 22 that escapes downward and a drain hole 23 that communicates with the drain discharge port 22 and escapes to the atmosphere are formed.

  On the inner periphery of the drain hole 23, a spiral groove 24 a is formed in which the axial cross section of the drain hole 23 is serrated and has a single spiral. Since the groove width of the spiral groove 24a is serrated, it becomes narrower toward the bottom of the spiral groove 24a. Further, the spiral groove 24 a is formed so as to be connected from the opening 25 side to the bottom 26 side of the drain hole 23.

  Next, the water droplet-shaped cooling water that has leaked into the space 18 will be described.

  The water droplet-shaped cooling water leaking into the space 18 moves to the drain outlet 22. When it moves to the drain discharge port 22, it flows below the drain discharge port 22 due to gravity and the leaked cooling water moves to the drain hole 23. When the leaked cooling water reaches the drain hole 23, it enters the spiral groove 24 a formed on the inner periphery of the drain hole 23. The leaked cooling water travels along the inner periphery of the drain hole 23 toward the opening 25 and the bottom 26 along the spiral groove 24a by capillary action. Therefore, it takes time until the leaked cooling water flows out from the opening 25, and a time for drying the leaked cooling water can be obtained.

  Generally, since the cylinder block 11 to which the body 10 is fixed has heat, the heat of the cylinder block 11 is transferred to the body 10 side, and the leaked cooling water is dried by the heat of the body 10. In addition, the surface area of the leaked cooling water that comes into contact with the atmosphere is larger than that without the spiral groove 24a, and the leaked cooling water can be dried in a short time. Therefore, it is possible to prevent the leaked cooling water from drying before reaching the opening 25 of the drain hole 23 and flowing out from the opening 25 to the outside.

  A second embodiment of the present invention will be described with reference to FIG.

  The present embodiment is different only in that the spiral groove 24b is formed in the drain discharge port 22 of the first embodiment, and the other configuration is the same, and the description other than the drain discharge port 22 is omitted.

  A spiral groove 24 b is formed on the inner periphery of the drain discharge port 22. Since the groove width of the spiral groove 24b is serrated, it becomes narrower toward the bottom of the spiral groove 24b. The spiral groove 24b is formed so as to be connected from the space 18 side to the drain hole 23 side. Since the spiral groove 24b is formed in the drain discharge port 22 similarly to the drain hole 23, it takes more time for the leaked cooling water to flow out from the opening 25 than in the first embodiment. Therefore, since the time for drying the leaked cooling water can be obtained and the drying can be performed in a short time as compared with the first embodiment, the leaked cooling water can be prevented from flowing out from the opening 25. .

  A third embodiment of the present invention will be described with reference to FIG.

  The present embodiment is different only in that the spiral groove 24a of the first embodiment is changed to the groove portion 27, and the other configuration is the same, so that description other than the drain hole 23 is omitted.

  A plurality of serrated grooves 27 are formed in the lower part of the inner periphery of the drain hole 23. When the leaked cooling water tries to flow through the drain hole 23, the plurality of groove portions 27 act as flow path resistances, so that it becomes difficult to flow. Therefore, it takes time until it flows out from the opening 25, and it is possible to obtain time for drying the leaked cooling water during that time, so that the leaked cooling water flows out from the opening 25 to the outside. Can be suppressed.

  In the first and second embodiments, the spiral groove 24a is formed from the opening 25 side to the bottom 26 side of the drain hole 23. However, if the time for drying the leaked cooling water can be obtained, the spiral groove 24a is spiral. The place where the groove 24 a is formed may be a part between the opening 25 and the bottom 26. Similarly, in the third embodiment, the plurality of groove portions 27 are formed from the opening portion 25 side to the bottom portion 26 side of the drain hole 23, but if the time for drying the leaked cooling water can be obtained, The place where the groove 27 is formed may be a part between the opening 25 and the bottom 26.

  The spiral groove 24a of the first and second embodiments and the spiral groove 24b of the second embodiment are a single spiral groove formed by one groove, but a plurality of spiral grooves such as a double spiral groove formed by two grooves. The spiral groove may be used.

Sectional drawing of the water pump in the 1st Embodiment of this invention. Sectional drawing of the water pump in the 2nd Embodiment of this invention. Sectional drawing of the water pump in the 3rd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Body 11 ... Cylinder block 12 ... Bearing 13 ... Rotating shaft 14 ... Pulley bracket 15 ... Drive pulley 16 ... Impeller 17 ... Mechanical seal 17a ... Seal Portion 18 ... Space 20 ... Vapor drain port 21 ... Vapor hole 22 ... Drain discharge port 23 ... Drain holes 24a, 24b ... Helix groove (groove)
25 ... opening 26 ... bottom 27 ... groove (groove)

Claims (4)

An impeller provided at one end of a rotating shaft supported by a body via a bearing;
A mechanical seal provided between the impeller and the bearing;
A drain hole formed below the body and discharging water droplets leaked from the impeller side through the mechanical seal to the outside of the body;
A drive pulley for rotating the impeller via the rotating shaft,
A water pump characterized in that a groove extending in the circumferential direction of the drain hole is formed on the inner periphery of the drain hole while the axial section of the rotating shaft forms a plurality of V shapes. In claim 1,
The water pump according to claim 1, wherein the groove has a sawtooth shape in an axial section of the rotating shaft. In claim 1 or claim 2,
The water pump is characterized in that the groove is formed in a spiral shape on the inner periphery of the drain hole. In claim 1 or claim 2,
The water pump according to claim 1, wherein the groove is formed at least on the lower side of the inner periphery of the drain hole.

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