JP2008202444A - Water pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a water pump capable of improving productivity, simplifying assembly, and increasing degree of freedom in attachment. <P>SOLUTION: In the water pump 1 provided with a pump cover 5 rotatably holding a pump shaft having an impeller attached thereon, a pump housing 7 having a pump chamber storing the impeller formed thereon, having an annular groove part 9 formed on at least one end surface of flange parts 5A, 7A formed on the pump cover 5 and the pump housing 7 respectively, and having the pump cover 5 and the pump housing 7 joined and integrated by joining both flange parts 5A, 7A under a condition where a seal ring 10 is installed in the groove part 9, both of the flange parts 5A, 7A are joined with gripping outer circumference parts of flange parts 5A, 7A of the pump cover 5 and the pump housing 7 by an elastically deformable U-shape cross section clip 17. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a water pump provided in a water-cooled engine.

  For example, a water-cooled engine for automobiles is provided with a water pump for circulating cooling water between a water jacket and a radiator in the engine body. Here, an example of a conventional water pump will be described with reference to FIGS. 4 and 5 (see Patent Document 1).

  4 is a side sectional view of a conventional water pump, FIG. 5 is a sectional view taken along line BB of FIG. 4, and the illustrated water pump 1 ″ can rotate a pump shaft 3 to which an impeller 2 is attached by a bearing 4. And a pump housing 7 in which a pump chamber 6 for housing the impeller 2 is formed, and a pulley 8 is provided at an end of the pump shaft 3 protruding outside the pump cover 5. Although not shown, an endless drive belt is wound between the pulley 8 and the drive pulley attached to the end of the crankshaft.

A cover-side flange portion 5A is formed at an end portion of the pump cover 5 facing the pump housing 7, and a housing-side flange portion 7A is formed at an end portion of the pump housing 7 facing the pump cover 5. An annular groove portion 9 is formed on the end surface of the housing side flange portion 7A. A seal ring 10 is attached to the groove 9, and a plurality (five in the illustrated example) of stud bolts 11 are erected on the housing side flange 7 </ b> A. Further, bolt insertion holes 12 are respectively provided at positions corresponding to the stud bolts 11 of the cover side flange portion 5A.

  Thus, as shown in FIG. 4, the pump cover 5 has each stat bolt erected on the housing side flange portion 7 </ b> A of the pump housing 7 in each bolt insertion hole 12 penetrating the cover side flange portion 5 </ b> A. 11, the nut 13 screwed into each stud bolt 11 is tightened and the cover side flange portion 5 </ b> A is fastened to the housing side flange portion 7 </ b> A to be coupled and integrated with the pump housing 7, thereby assembling the water pump 1 ″ It is done.

  In the water pump 1 ″ assembled as described above, the impeller 2 is accommodated in a pump chamber 6 formed in the pump housing 7, and the pump chamber 6 is sealed by a mechanical seal 14. Cooling water leakage to the outside of the pump chamber 6 is prevented.

  Then, as shown in FIG. 4, the water pump 1 ″ is formed by bolts (not shown) inserted into a plurality (four in the illustrated example) of bolt insertion holes 15 formed in the cylinder block mounting flange 7 </ b> B of the pump housing 7. It is attached to a cylinder block of an engine (not shown).

  Thus, when the engine is started and the crankshaft is driven to rotate, the rotation is transmitted to the pump shaft 3 of the water pump 1 "via the drive pulley, the drive belt and the pulley 8 (not shown). The impeller 2 attached thereto is rotationally driven.When the impeller 2 rotates in the pump chamber 6, the cooling water sucked into the water pump 1 "is boosted by the impeller 2, and the water pump 1" The water is discharged outside, and the cooling water is circulated between the water jacket and the radiator in the engine body.

In addition to the above type, a water pump of a type in which a pump housing holding a pump shaft to which an impeller is attached is mounted in a pump chamber formed in a cylinder block is known (for example, see Patent Document 2). ).
JP 2002-364585 A Japanese Utility Model Publication No. 6-022595

  However, the conventional water pump 1 ″ shown in FIGS. 4 and 5 employs a configuration in which the pump cover 5 is fastened to the pump housing 7 by the stud bolt 11 and the nut 13. There is a problem that it is necessary to perform a plurality of tappings on the flange portion 7A, and a processing facility for the tapping is required, and the number of processing steps increases, resulting in an increase in cost.

  Further, in order to form the groove portion 9 for mounting the seal ring 10 in the housing side flange portion 7A of the pump housing 7, the housing side flange portion 7A needs to have a certain width or more, and the tap hole 16 Since it is necessary to process at a position offset outward from the groove 9 while avoiding the groove 9, the boss 7a of the housing side flange 7A for processing the tap hole 16 is outward by L2 shown in FIG. Project to For this reason, there is a problem that the degree of freedom of layout of other parts and the water pump 1 ″ itself is limited.

  The present invention has been made in view of the above-mentioned problems, and the object process thereof is to provide a water pump that can improve productivity and simplify assembly, and can increase the degree of freedom in mounting. There is.

  To achieve the above object, the invention according to claim 1 includes a pump cover that rotatably holds a pump shaft to which an impeller is attached, and a pump housing in which a pump chamber that houses the impeller is formed, An annular groove is formed on at least one end face of the flange formed on each of the pump cover and the pump housing, and the flange cover is joined to each other with the seal ring attached to the groove. In the water pump formed by coupling and integrating the pump housing, the flange portions of the pump cover and the flange portions of the pump housing are sandwiched between the flange portions of the pump cover and joined by flanges that are elastically deformable. It is characterized by that.

  According to a second aspect of the present invention, in the first aspect of the present invention, the pump shaft is rotationally driven by an electric motor.

  According to the first aspect of the present invention, the flange portions of the pump cover and the pump housing are sandwiched between the flange portions of the pump cover and the pump housing by the elastically deformable U-shaped clip. Pump assembly is simplified.

  Further, since it is not necessary to form bolt insertion holes and tap holes in the flange portion of the pump cover and the pump housing as in the bolted fastening structure, the productivity of the water pump can be increased and the cost can be reduced. .

  Furthermore, since the clip can be sandwiched in a position overlapping the seal ring in the radial direction of the water pump, the radial dimension of the flange portion of the pump cover and the pump housing can be reduced compared to the fastening structure with bolts, so that both flange portions can be It can be downsized. For this reason, the space occupied by the water pump is reduced, and the degree of freedom of mounting the water pump to the engine is increased.

  According to the second aspect of the present invention, a pulley is attached to the pump shaft, and the joint surface between the pump cover and the flange portion of the pump housing is separated as compared with the configuration in which the driving force is transmitted to the pump shaft through the driving belt and the pulley. The force can be reduced. As a result, the elastic force (clip force) required for the clip is small, and the clip itself can be miniaturized. For this reason, the degree of freedom of attachment of the water pump to the engine is increased, and the attachment of the clamp is improved.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

<Embodiment 1>
1 is a fracture cross-sectional view of a water pump according to Embodiment 1 of the present invention, and FIG. 2 is a cross-sectional view taken along the line AA of FIG. 1, which is the same as that shown in FIGS. Elements are denoted by the same reference numerals, and description thereof will be omitted below.

  In the present embodiment, the outer peripheral portion of the cover-side flange portion 5A of the pump cover 5 and the housing-side flange portion 7A of the pump housing 7 is formed by a metal clip 17 having a U-shaped (channel shape) that can be elastically deformed. The water pump 1 is assembled by joining the flange portions 5A and 7A together so that the pump cover 5 and the pump housing 7 are coupled and integrated. The clip 17 is made of a metal such as spring steel.

  Here, as shown in FIG. 2, the cover-side flange portion 5A of the pump cover 5 and the housing-side flange portion 7A of the pump housing 7 are sandwiched by clips 17 at five locations in the circumferential direction of the outer peripheral portion. When the pump 1 is assembled, the cover-side flange portion 5A of the pump cover 5 is overlapped with the housing-side flange portion 7A of the pump housing 7, and the clips 17 are arranged in the circumferential direction at the five outer circumferential portions of the flange portions 5A and 7A. Just pinch from the outside. Therefore, the assembly of the water pump 1 can be simplified, the number of assembling steps can be reduced, and the cost can be reduced.

  Thus, the water pump 1 that is simply assembled as described above is provided with bolts (not shown) inserted through a plurality of bolt insertion holes 15 formed in the cylinder block mounting flange 7B of the pump housing 7 as in the conventional case. It is attached to a cylinder block of an engine (not shown).

  Further, in the water pump 1 according to the present embodiment, bolt insertion holes and tap holes are formed in the flange portions 5A and 7A of the pump cover 5 and the pump housing 7 as in the conventional water pump 1 "shown in FIGS. Therefore, the productivity of the water pump 1 can be increased and a large-scale processing facility is not required, and the number of processing steps can be reduced and the cost can be reduced.

  Further, as shown in FIG. 2, the clip 17 can be sandwiched at a position overlapping the seal ring 10 in the radial direction of the water pump 1, so that the flanges of the pump cover 5 and the pump housing 7 can be compared with the fastening structure using bolts. The flanges 5A and 7A can be reduced in size by reducing the radial dimensions of the portions 5A and 7A. Specifically, FIG. 5 shows a radially outward protrusion amount L1 at five circumferential positions (sandwich portions) of the outer peripheral portion sandwiching the clips 17 of the flange portions 5A and 7A of the pump cover 5 and the pump housing 7. It can be suppressed to be smaller than the protrusion amount L2 of the boss portion 7a (L1 <L2). For this reason, the space occupied by the water pump 1 is reduced, and the degree of freedom of attachment of the water pump 1 to the engine is increased.

<Embodiment 2>
Next, a second embodiment of the present invention will be described with reference to FIG.

  FIG. 3 is a side sectional view of a water pump according to Embodiment 2 of the present invention. In this figure, the same elements as those shown in FIGS. The re-explanation about is omitted.

  The water pump 1 ′ according to the present embodiment is characterized in that the pump shaft 3 is rotationally driven by an electric motor 18, and the pump shaft 3 is directly connected to the electric motor 18. The other configuration of the water pump 1 ′ according to the present embodiment is the same as the configuration of the water pump 1 according to the first embodiment shown in FIGS. 1 and 2.

  In the configuration in which the pulley 8 is attached to the pump shaft 3 and the driving force is transmitted to the pump shaft 3 via the drive belt and the pulley 8 as in the water pump 1 according to the first embodiment shown in FIGS. A large force acts to separate the joint surfaces of the cover 5 and the flange portions 5A and 7A of the pump housing 7.

  On the other hand, in the water pump 1 ′ according to the present embodiment that employs a system in which the pump shaft 3 is directly rotated by an electric motor 18 directly connected thereto, the fastening force of both flange portions 5A and 7A is a hydraulic pressure. It is sufficient to withstand the load caused by the above, and the force for separating the joint surfaces of the flange portions 5A and 7A can be kept small. As a result, the elastic force (clip force) required for the clip 17 is small, and the clip 17 itself can be miniaturized. For this reason, the degree of freedom of attachment of the water pump 1 ′ to the engine is increased, and the mountability of the clamp 17 is improved.

1 is a broken sectional view of a water pump according to Embodiment 1 of the present invention. It is the sectional view on the AA line of FIG. It is a sectional side view of the water pump which concerns on Embodiment 2 of this invention. It is a sectional side view of the conventional water pump. It is the BB sectional view taken on the line of FIG.

Explanation of symbols

1, 1 'Water pump 2 Impeller 3 Pump shaft 4 Bearing 5 Pump cover 5A Cover side flange 6 Pump chamber 7 Pump housing 7A Housing side flange 7B Cylinder block mounting flange 7a Housing side flange boss 8 Pulley 9 Groove 10 Seal ring 11 Stud bolt 12 Bolt insertion hole 13 Nut 14 Mechanical seal 15 Bolt insertion hole 16 Tap hole 17 Clip 18 Electric motor

Claims (2)

A pump cover that rotatably holds a pump shaft to which the impeller is attached, and a pump housing in which a pump chamber that houses the impeller is formed, and a flange portion formed on each of the pump cover and the pump housing. In the water pump formed by connecting and integrating the pump cover and the pump housing by forming an annular groove on at least one end face and joining the flanges with the seal ring attached to the groove.
A water pump characterized in that an outer peripheral portion of each flange portion of the pump cover and the pump housing is sandwiched between two flange portions by an elastically deformable U-shaped cross section clip.   The water pump according to claim 1, wherein the pump shaft is rotationally driven by an electric motor.

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