JP4336113B2 - Pump impeller clearance adjustment device - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a gap adjusting device for a pump impeller, and more particularly to a device for adjusting a gap between a blade blade front edge of a pump impeller and an inner surface of a suction cover.
[0002]
[Prior art]
In order to adjust the back gap of the pump that receives axial thrust force with the thrust bearing, it is adjusted by positioning with the thickness of the adjustment ring fixed to the rotating shaft and positioning with the thrust bearing contact surface of the stationary end cover Is conventionally performed (for example, refer to Patent Document 1).
[0003]
Rather than adjusting the back gap like this, it is also a conventional technique to adjust the discharge amount required during pump operation by adjusting the gap between the front edge of the slats and the inner surface of the suction cover according to the thickness of the adjustment ring As is commonly done. As a well-known technique according to the literature description, the suction cover joined to the lower surface of the opening of the open type pump casing is formed such that one surface is shallow and the other surface is deep, and the mounting surface of the suction cover is changed to the front and back. There exists what makes the gap change of an impeller (for example, refer patent document 2).
[0004]
Further, as a large-sized drainage pump, a device is known that adjusts a gap of an impeller by raising and lowering a liner provided facing the impeller by a hydraulic device (see, for example, Patent Document 3). .
[0005]
[Patent Document 1]
JP-A-5-195986 (paragraph number 0002)
[Patent Document 2]
Japanese Utility Model Publication No. 6-53798 (Fig. 5-6)
[Patent Document 3]
Japanese Utility Model Publication No. 64-27500 (drawing)
[0006]
[Problems to be solved by the invention]
Using an adjustment ring as in Patent Document 1 or turning the suction cover upside down as in Patent Document 2 is not only troublesome that the suction cover must be removed for each adjustment. There is a disadvantage that stepless fine adjustment is impossible. Moreover, the thing of patent document 3 becomes expensive with a complicated and large-sized apparatus, and cannot be applied to a small pump at all.
[0007]
The purpose of the present invention is to adjust the discharge amount required during the operation of the pump, without requiring the removal of the suction cover, and can be adjusted in a stepless manner with a simple operation, and can also be finely adjusted, and the anti-slack function An object of the present invention is to provide a gap adjusting device for an impeller for a pump which is excellent and has a simple structure and a low cost.
[0008]
[Means for solving problems]
In order to solve the above-mentioned conventional problems, in the gap adjusting device for a pump impeller according to claim 1 according to the present invention, in the fixing structure for fixing the pump impeller boss and the pump shaft, the pump shaft A male screw is engraved on the outer periphery of the guide lower part, a rear screw hole to be screwed with the male screw is drilled from the rear end surface of the impeller boss portion, and is screwed with a screw plug having a male screw engraved on the outer peripheral surface. A front screw hole is drilled from the front end of the impeller boss, the terminal end of the front screw hole and the terminal end of the rear screw hole are connected, and the outer periphery of the lower part of the pump shaft is screwed into the rear screw hole. It has a fixing structure consisting of a pump impeller boss, a pump shaft and a screw plug, which is formed by screwing a screw plug into the front screw hole and pressing and fixing the rear end surface to the front end surface of the pump shaft . By increasing or decreasing the threading depth of the pump shaft into the rear screw hole of the impeller, And gap adjusting the Nkaba, and to provide a gap adjusting device of the pump impeller, characterized in that for pressing the rear end face to the front end face of the pump shaft by screwing fixing screws plug to the front screw hole.
[0009]
Further, in the gap adjusting device for a pump impeller according to claim 2, on the premise of the configuration according to claim 1, the external thread engraved on the outer periphery of the lower portion of the pump shaft has the same direction as the rotation direction of the pump shaft. The male screw engraved on the outer peripheral surface of the fixing screw plug is rotated in the same direction as the rotation direction of the pump shaft. It was comprised so that it might screw with a front part screw hole in the aspect extended to the rear-end direction, turning.
[0010]
【Example】
Hereinafter, the present invention will be described with reference to the embodiments shown in FIGS.
[0011]
Reference numeral 1 denotes a pump shaft, and a male screw is engraved on the outer periphery of the lower portion of the guide shaft. The male screw is engraved in the direction of the tip while turning around the same direction as the rotation direction of the pump shaft 1. It is desirable that it be extended. That is, when the pump shaft 1 rotates clockwise as viewed from the prime mover side, a right-hand thread is used.
[0012]
Reference numeral 3 denotes a rear screw hole drilled from the rear end surface of the impeller boss portion, and a female screw that is screwed with a male screw on the outer periphery of the lower portion of the pump shaft 1 is formed on the inner peripheral surface. Reference numeral 5 denotes a front screw hole drilled from the front end surface of the impeller boss portion 3, and a terminal portion of the front screw hole 5 is electrically connected to a terminal portion of the rear end screw hole 4.
[0013]
Reference numeral 6 denotes a fixing screw plug. On the outer peripheral surface thereof, a male screw that is screwed with the female screw of the front screw hole 5 is engraved. For example, the front end surface of the fixing screw plug 6 is preferably extended to the rear end direction while turning in the same direction as the rotation direction, and the front end portion of the fixing screw plug 6 is used for engaging a screw tool such as a wrench. A square hole is provided in the center, or the vicinity of the front end portion of the outer peripheral surface is formed in a polygon.
[0014]
The impeller 2 is mounted by screwing the outer periphery of the lower portion of the pump shaft 1 into the rear screw hole 4, but the screwing depth of the pump shaft 1 into the rear screw hole 4 in the impeller 3 can be increased or decreased. Thus, after adjusting the gap G between the lower edge of the blade plate 7 and the upper surface of the suction cover 8 to a predetermined value, the fixing screw plug 6 is screwed into the front screw hole 5 and the rear end surface thereof is pump shaft. 1 is brought into pressure contact with the leading end surface of the impeller 1, the impeller boss 3 is strongly fixed by a strong double nut effect due to the strong screwing torque accompanying the screwing action of the impeller boss 3 from both front and rear directions. It will be.
[0015]
Then, the external thread engraved on the outer periphery of the lower part of the pump shaft 1 is screwed into the rear screw hole 4 in a manner of extending in the distal direction while turning about the same direction as the rotation direction of the pump shaft 1, and The male screw engraved on the outer peripheral surface of the fixing screw plug 6 is screwed into the front screw hole 5 in such a manner that the male screw is guided in the rear end direction while turning around the same direction as the rotation direction of the pump shaft 1. It is configured as follows.
[0016]
In this case, due to the water resistance received by the impeller 2 when the pump is driven, a slight displacement occurs in the radial direction on the screwing surface between the pump shaft 1 and the rear screw hole 4 to generate a strong thrust in the rear. At the same time, a backward thrust is also generated between the fixing screw plug 6 and the front screw hole 5, and these thrusts combine to make the rear end surface of the fixing screw plug 6 the front end surface of the pump shaft 1. As a result, the impeller boss portion 3 is more firmly fixed.
[001 7 ]
【The invention's effect】
According to the present invention, the gap between the front edge of the slat and the inner surface of the suction cover, which is an adjustment factor of the discharge amount required during the operation of the pump, can be easily operated without requiring removal of the suction cover. It is possible to provide a gap adjusting device for a pump impeller that can be adjusted steplessly, can be finely adjusted, has an excellent anti-loosening function, and has a simple structure and a low cost.
[001 8 ]
Furthermore, the effect of the invention of claim 2 is that the impeller boss is more firmly fixed by rotating the pump.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional side view of a main part, which is an embodiment of a pump impeller provided with the device of the present invention, and shows a state where a gap between a blade blade front edge and an inner surface of a suction cover is widely adjusted.
FIG. 2 is a longitudinal sectional side view of an essential part, which is an embodiment of a pump impeller provided with the device of the present invention, and shows a state in which a gap between a blade front edge and a suction cover inner surface is adjusted narrowly.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Pump shaft 2 Impeller boss part 4 Rear screw hole 5 Front screw hole 6 Screw cap for fixing 7 Blade plate 8 Suction cover G Gap

Claims (2)

In the fixing structure for fixing the pump impeller boss to the pump shaft, a male screw is engraved on the outer periphery of the lower portion of the pump shaft, and a rear screw hole to be screwed with the male screw is provided at the rear end surface of the impeller boss. A front screw hole is formed from the front end of the impeller boss, and a front end of the front screw hole and the rear screw hole. The end portion of the pump shaft is made conductive, the outer periphery of the lower portion of the pump shaft is screwed into the rear screw hole, the screw plug is screwed into the front screw hole, and the rear end surface is pressed and fixed to the front end surface of the pump shaft. By having a fixed structure consisting of a pump impeller boss, a pump shaft, and a screw plug , the gap between the pump cover and the suction cover is adjusted by increasing or decreasing the screwing depth of the pump shaft into the rear screw hole of the impeller, and Screw the fixing screw cap into the front screw hole and place the rear end face in front of the pump shaft. Gap adjusting device of the pump impeller, characterized in that for pressing on a surface.   A male screw engraved on the outer periphery of the lower portion of the pump shaft is screwed into the rear screw hole in a manner of extending in the tip direction while turning about the same direction as the rotation direction of the pump shaft, and a fixing screw The male screw engraved on the outer peripheral surface of the stopper is configured to be screwed into the front screw hole in a manner of extending in the rear end direction while turning in the same direction as the rotation direction of the pump shaft. The gap adjusting device for an impeller for a pump according to claim 1.

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