US2404678A - Impeller - Google Patents

Description

C. E.-WUENSCH IMPELLER Filed June 5, 1944 2. Sheets-Shae? 1 INVENTOR. CHARLES Ema WUENSCH July 23; 1946.

C. E. WUENSCH July 23, 1946.

IMPELLER Filed June 5, 1944 2 Sheets-Sheet 2 INVENTOR. CHARLES ERG WUEH CH BY r 1111111 ll/IIIIIIIIII Patented July 23; 1946 OFFICE f INIIELLER V Charles Erb Wuensch, Saratoga, Calif.

Application June 5, 1944, Serial No. 538,794

This invention relates to impellers, and more particularly to flexible resilient blades for the impellers of centrifugal pumps.

- Among the objects of the invention is the prevention of injury to the blades of the impeller by oversize objects in the flow passing through the pump which would otherwise damage the pump and stop the operation.

Another object is to provide a blade that will flex to permitanobstruction to pass and then be restored to normal operative shape by th centrifugal force of the operation.

A further object is to prevent excessive wear of the blades in pumping abrasive materials.

Further objects are to provide a construction of maximum simplicity, economy and ease of assembly and contemplates such other and further advantages as will appear to one skilled in the art as the description thereof proceeds.

In attaining the foregoing objects, together with such further benefits, advantages and capabilities as may hereinafter appear and as inherently possessed thereby, there is disclosed byway of illustration only, the constructions shown in the accompanying drawings. It is to be understood, however, that the invention is not limited to the examples shown because the same may be embodied in further modifications within the spirit of the invention as set forth in the claim followingthe description.

Referring to the drawings: c.

Figure 11s a side elevation of a centrifugal pump with a portion of the casing broken away to disclose an impeller having blades constructed in accordance with this invention.

Figure 2 is an enlarged longitudinal section of a. single blade of an impeller. j

Figure 3 is an enlarged front elevational view of a single blade.

- Figure 4 is an enlarged longitudinal section of a single blade representing a modification.

Figure 5 is a fragmentary front elevation of a blade with a portion of the hub in section showing a detail of the attachment.

Figure 6 is an enlarged view of an im eller blade showing tangential mounting and also il1us trating the positions assumed during operation and at rest.

Figure 7 is an enlarged view of a variant form of blade.

Referring now more particularly to the drawings, the impeller of the present invention com prises a series of radially extending blades 2 which are securely mounted in or upon a hub 8 rotatlng Within a housing or casing which is generally .7 Claims. (01. 10 -115) 1 2 composed of sides Xl and X-Z and acylindrical bowl .X-3. It is to be understood that the impeller and particularly the blades of the present invention are useful especially in apparatus where fluids with abrasive materialsin suspension are circulated or agitated. While: it is preferred to attach and dispose the blades 2 radially from the hub 8, it is to be understood that they may extend tangentially from the hub if desired as shown in Figures 6 and 7.

One construction or the blades 2 may be described as comprising a series of spaced metal wires orcables 1. arranged in a common plane extending in spaced relation substantially across the entire width of the blade 2.- The inner ends of the wires I are bent around an anchor key 3 and maybe bent back upon themselves as at 4, to reinforce the lowerportion of the blade 2. In the event greater strength is desired. for the core, the wires or cables can be continued so that the ends of each wire I terminates at the point of beginning. It is preferable, however, to give thereturning end a lateral twist so that all of the wires I lie in the same plane and do not double back on each other as shown in Figure 1.- The outer ends of the wires may have eyelets 5" formed thereon or may be flattened or left as they are. The purpose of flattening the wires l or forming eyelets as shown in Figure 2 is to assist in anchoring a weight 5. The weight 5 may be lead or any other suitable Weight which can be cast or otherwise maintained around the outer ends of the wires or cables I. The advantage of casting the weight 5 around the outer ends of the wires l is to secure the assembly in a permanent arrangement which will then form a reinforcing core for the blade 2. The purpose of weighting the outer ends of the blades is to give rigidity at this point and also to stretch the blades slightly so as to minimize any tendency through centrifugal action to become larger in cross sectional diameter or area at the point of maximum flexure.

The external body of the blade 2 which forms it into a structure having a rectangular horizontal section is composed of rubber or other highly resistant and resilient compound I which can be vulcanized or otherwise formed around and enclose the core and weight 5 to make the comsubstances and eliminates corrosion when the impeller is idle.

In operation the bulblike end of the blade 2 presents an impact surface substantially similar to that shown in the position I of Figure 1 and V of Figure 6. However, if the blade is made inclined slightly forward as shown in the broken line IV of Figure 4 it will straighten out under the load of pumping and as a result of centrifugal force. Accordingly it will present an impact surface corresponding substantially to the rest position shown in full lines in Figure 1. An advantage from inclining the position of rest slightly forward resides in the fact that there will be less slip stream loss in the operation.

In order to completely armour the impeller it will be desirable to armour the exposed surfaces of the hub as shown at Ia. This will protect all of the exposed surfaces with a resilient armoured coating and likewise prevent rusting during nonoperating periods.

I claim:

1. A flexible impeller blade for centrifugal pumps comprising in combination a flexible core extending substantially its entire length, a Weight secured to the outer end of said core to form an enlaregd bulb-like end, means at the other end of said core for securing the blade to a hub, and a flexible resilient covering for said core and said weight said structure being capable of momentary distortion and flexing to pass an obstacle and return to its normal state without stopping the operation of a pump.

2. A flexible impeller blade for centrifugal pumps comprising in combination a flexible core extending substantially its entire length, a weight secured to the outer end of said core to form an enlarged bulb-like end, means at the other end of said core for securing the blade to a hub, and a flexible resilient covering for the entire blade said structure bein capable of momentary distortion and flexing to pass an obstacle and return to its normal state without stopping the operation of a pump.

3. A flexible impeller blade for centrifugal pumps comprising in combination a flexible core extending substantially its entire length, a weight secured to the outer end of said core to form an enlarged bulb-like end, means at the other end of said core for securing the blade to a hub, and

a flexible internally reinforced resilient coverin for the blade said structure being capable of momentary distortion and flexing to pass an obstacle and return to its normal state without stopping the operation of a pump.

4. An impeller for centrifugal pumps comprising in combination a hub, and a plurality of blades flexible substantially from hub to tip, each weighted at the outer end to form an enlarged bulb-like end and each armoured with a resilient flexible coating said structure bein capable of momentary distortion and flexing to pass an obstacle and return to its normal state without stopping the operation of a pump.

5. An impeller for centrifugal pumps comprising in combination a hub, a coating of resilient armour on said hub, and a plurality of blades flexible substantially from hub to tip adapted to be held by said hub and extended outward therefrom, each weighted at the outer end to form an enlarged bulb-like end and each armoured with a resilient flexible coating said structure being capable of momentary distortion and flexing to pass an obstacle and return to its normal state without stopping the operation of a pump.

6. A flexible impeller blade for centrifugal pumps comprising in combination a sac of resilient flexible material adapted to be sealed at its inner end adjacent the hub to form a closed cavity therein, and a free moving weight in said cavity adapted to and capable of moving longitudinally therein in response to external forces such as pressure, centrifugal force and distortion said structure being capable of momentary distortion and flexing to pass an obstacle and return to its normal state without stopping the operation of a P mp.

7. A flexible impeller blade for centrifugal pumps comprising in combination a sac of resilient flexible internally reinforced material adapted to be sealed at its inner end adjacent the hub to form a closed cavity therein, and a weight in said cavity adapted to and capable of moving longitudinally therein in response to external forces such as pressure, centrifugal force and distortion said structure being capable of momentary distortion and flexing to pass an obstacle and return to its normal state without stopping the op eration of a pump.

CHARLES ERB WUE'NSCH.

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