JPS63243497A - Dust removal device for impeller - Google Patents

Abstract

PURPOSE:To prevent an impeller from deteriorating its performance due to dust, by providing a protrusive objects or the like in an inlet part of the impeller thus generating a distortion in an inflow of fluid to the impeller causing its blade to resonate so that the dust, adhering to the blade, is surely removed. CONSTITUTION:An impeller 6 provides in its inlet part a protrusive object 1, and this object 1 is enabled to move in the diametric direction while provided in an equal space by a quantity (n) in the peripheral direction. Further the protrusive object 1 is mounted to a casing 2 while constituted of a cylinder 3, 0 ring 4 and a moving screw thread part 5 so that the protrusive object 1 is able to vertically move. And the protrusive object 1 is protruded into the casing 2 generating a flow distortion of quantity (n) by the protrusive object 1 of quantity (n) thus forcedly vibrating a blade of the impeller 6. In this way, dust, which adheres to a surface of the blade, is surely removed.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a compressor or blower having an axial impeller or a compressor or blower having a centrifugal impeller, and particularly relates to a compressor or blower having an axial impeller or a centrifugal impeller. The present invention relates to a dust removal device suitable for removing dust from an open type impeller.

[Conventional technology]

In a blower or compressor, if dust adheres to the impeller during operation, the rotor will become unbalanced and vibrations will increase, leading to accidents such as bearing damage. To prevent this, it is customary to install a filter upstream of the impeller to remove dust. However, the fine particles passing through the filter eyes adhere to the impeller blades during long-term operation, causing the aforementioned unbalance.Furthermore, the adhesion of dust greatly increases the coefficient of friction on the impeller surface. This increases friction loss and causes performance to deteriorate. To prevent these problems, it is usually necessary to periodically disassemble and clean one impeller, but this is not possible when the compressor or blower cannot be stopped, and there are many disassembly and reassembly procedures. Therefore, there is a need for a device that can somehow remove these dusts during operation. In the conventional device, as described in Japanese Patent Application Laid-Open No. 59-1735'J9, a cutout is provided at the impeller inlet, and a member is inserted into the cutout to scrape off dust.

[Problem that the invention seeks to solve]

The above-mentioned conventional device has the drawback that dust can be removed only at the location where the member is inserted at the blade inlet, but dust from most other locations cannot be removed.

Therefore, in this device, scales cannot be avoided due to unbalance caused by dust adhering to other parts of the impeller. In addition, there is a drawback that performance deterioration cannot be avoided. Therefore,
There is a need for a device that can remove dust from the blades over the entire surface.

The present invention has been made based on the above-mentioned problems, and an object of the present invention is to provide a dust removal device that can reliably remove dust attached to blades.

[Means for Solving the Problems] The above object is achieved by forcibly vibrating the blades of one impeller during operation to remove dust attached to the impeller. Vibrating the impeller during M@ can be achieved by the following technique.

In the case of trickle impellers or open impellers, each blade has the same natural frequency. Let this be frs (Hz). If the excitation frequency fa (Hz) can be generated steadily using a fluid, the blades will be in a strong acid vibration state and each blade will vibrate greatly, and the dust attached to the blades will be removed by this vibration. , it is removed as if a feather were hit with a hammer. Fluid attack of fn (Hz) can be achieved as follows.If n fluid fluctuations are equally distributed in the circumferential direction of the 0-impeller force population, the impeller becomes N (
rpm), it is possible to force the blade to vibrate by adjusting n so that fluid excitation is established.

The generation of fluid pulsation can be achieved by creating n flow distortions by providing n protrusions at the inlet of one blade. Also, instead of the protrusion, it is also possible to allow n jets to flow in from the outer circumference on the inlet side.

[Effect]

According to the present invention, the blades of the impeller are forced into a photographed state during operation, and the dust attached to the blade surface is removed.

removed. The forced vibration is related to the impeller inlet flow with the natural frequency fa (Hz) of the impeller, n==60Xfa
/N where N impeller rotation speed (rpm) It is possible to create n pulsations using a protrusion method or a fluid jet method. In this way, the impeller can be vibrated arbitrarily during operation, and dust attached to the surface of one blade can be removed.

〔Example〕

Embodiments of the present invention will be described below with reference to the first drawing.

1 and 2 show an embodiment of the device of the present invention, and in these figures, a protrusion 1 provided at the inlet of one impeller 6 is movable in the radial direction, and is movable in the circumferential direction. n pieces 1
Provided at equal intervals. This is the number determined here.

The protrusions 1 cause n flow distortions, which generate forced vibrations. The protrusion 1 is attached to a casing 2, and is comprised of a cylinder 3, an O-ring 4, and a threaded portion 5 for movement so as to be movable up and down. By turning the protrusion 1, the screw mechanism allows the protrusion to be taken in and out as required.

The insertion and removal of this protrusion can also be automatically and remotely controlled by using a hydraulic system or the like. Note that the purpose of this protrusion is to cause distortion in the flow, and its shape is not particularly limited.

FIGS. 3 and 4 show another embodiment of the apparatus of the present invention, in which the flow is distorted by a fluid jet. Impeller 6 population section casing 2
N ejection holes 7 are provided in a uniform distribution, and fluid is ejected from these holes 7.

A jet flow is easily possible by introducing the fluid at a higher pressure than the fluid at the inlet, for example the discharge side, through the conduit 8.

If necessary, by opening the valve 9, a jet flow is generated from the jet hole 7, and n flow distortions can be created on the circumference. The number of n holes is determined by the above-mentioned relational expression.

〔Effect of the invention〕

According to the present invention, since dust is removed by creating a forced vibration state using the natural frequency of the blade, dust is reliably removed and performance deterioration can be prevented.

[Brief explanation of the drawing]

Claims (1)

[Claims] 1. In a blower or compressor having an axial flow impeller or an open centrifugal impeller, distortion is caused in the flow flowing into the impeller, the blades of the impeller are brought into a resonance state, and the blades are An impeller dust removal device comprising a means for removing attached dust. 2. The impeller dust removing device according to claim 1, wherein the dust removing means is a protrusion disposed at intervals along the circumferential direction in front of the impeller inlet. 3. The impeller dust removal device according to claim 1, wherein the dust removal means includes fluid ejection holes arranged at intervals in the casing in front of the impeller inlet.