US2853021A

US2853021A - Pump

Info

Publication number: US2853021A
Application number: US481867A
Authority: US
Inventors: Doble Warren
Original assignee: Jabsco Pump Co
Current assignee: Jabsco Pump Co
Priority date: 1955-01-14
Filing date: 1955-01-14
Publication date: 1958-09-23
Anticipated expiration: 1975-09-23

Description

. Sept. 23, 1958 w. DOBLE 2,853,021

PUMP

File d Jan. 14, 1955 6.2 74 60 64 14 16 48 66 2o J l 1 I6 46 C i 1 Tk r r ::m

Il 68 52 50 5a 68 INVENTOR' WARREN DOBLE FY HIS ATTORNEYS HARRIS, KIECH, lbsrsn HARRI$ United States Patent PUMP Warren Doble, North Ho ood, Cnllh, alsignor to Illnco Pump Company, ank, Calll'., n corporatlon of California Application January 14, 1%, Serial No. 481,867 4 Clalms. (Cl. 103-117) The present invention relates in general to pumps and, more particularly, to pumps of the rubber-impeller type, the term rubber, as used herein, being intended to include not only natural rubber, but any material, such as the so-called synthetic rubbers, having physical characteristics or properties generally similar to those of natural rubber, particularly as to flexibility and resilience.

A general object of the invention is to provide an improved pump of the foregoing general character which may be manufactured considerably more economically than prior pumps of this character without any sacrifice in quality.

More particularly, an object of the invention is to provide a pump which includes a pump housing having a body portion provided with an axial extension at one end thereof, an impeller chamber in the body portion of the pump housing, a bore in the pump housing extension and communicating at one end with the impeller chamber, a shaft extending through the bore into the impeller chamber, an impeller in the impeller chamber, means. for transmitting rotation of the shaft to the impeller, a bearing for the shaft in the bore, and sealing means in the bore for preventing leakage along the shaft from the impeller chamber and/or bearing.

Another object of the invention is to provide an impeller chamber which is defined by a counterbore in the body portion of the pump housing and coaxial with the bore in the pump-housing extension, and by a cam in the counterbore at one side thereof, the cam being adapted to flex the vanes of the impeller to produce the desired pumping action, as is well known in the art. With this construction, both the bore in the pump-housing extension and the counterbore in the body portion of the pump housing may be formed simultaneously from one end of the pump housing with a suitable boring tool, thereby reducing manufacturing costs, which is an important feature of the invention.

N- Another object is to provide a pump wherein the shaft and its bearing constitute a unit of the type conventionally used in automotive fan and water pump combinations, such shaft and bearing units being reliable, but inexpensive, thereby minimizing the cost of the pump of the invention, which is an important feature.

Another object is to provide a sealing means which includes seals in the pump-housing extension for preventing leakage from both the impeller chamber and the bearing. In this connection, an object of the invention is to retain certain of the seals in the pump-housing extension by means of shoulders formed at the junction of the bore in such extension with coaxial holes and/or counterbores in the extension. Such holes and/or counterbores may be bored from the-same end of the pump housing as the bore in the pump-housing extension and the counterbore in the body portion of the pump housing, and in the same operation, which is another feature of the invention.

In addition to the foregoing features, the pump of the invention embodies various features disclosed and claimed "ice and which is telescoped over the shaft in torque transmitting relationship, the impeller insert having an axial extension which projects through and is encompassed and engaged by a seal for preventing leakage from the impeller chamber. With such a construction, wear produced by the seal is confined to the impeller-insert extension to eliminate wear of the shaft by the seal, which is an important feature of the invention disclosed in said application Serial No. 447,163.

In accordance with the present invention, an important object is to carry the impeller-insert extension-through another, secondary seal which is spaced from the first or primary seal and which preferably serves as one of the seals for the bearing hereinbefore mentioned, a bleed hole for leakage communicating with the space between the primary and secondary seals. With such a construction, any small amount of fluid escaping from the impeller chamber past the primary seal can contact only the exterior of the impellerinsert extension and cannot come in contact with the shaft itself, any such leakage being confined in the space between the primary and secondary seals by the secondary seal and draining off through the bleed hole. Consequently, fluid leakage past the primary seal cannot seep between the impeller insert and the shaft to cause the insert to stick to the shaft, as by rusting or otherwise corroding the shaft or insert, for example. Thus, the impeller and the insert molded therein can always be removed from the shaft readily for replacement, which is an important feature.

The foregoing objects, advantages and features of the present invention, together with various other objects, advantages and features thereof which will become apparent, may be attained with the exemplary embodiment of the invention illustrated in the accompanying drawing and described in detail hereinafter. Referring to the drawing:

Fig. 1 thereof is a longitudinal sectional view of a pump embodying the invention; and

Fig. 2 thereof is a fragmentary longitudinal sectional view duplicating a portion of Fig. 1, but illustrating another embodiment of the invention.

Referring to Fig. l of the drawing, the numeral 10 designates a housing or housing means shown as comprising a one-piece pump housing having a body portion 12 and an axial extension 14 at one end of the body portion. The outer end of the extension 14 is provided with a hole 16 therethrough, and the extension is provided with a bore 18 therein of constant diameter which extends from the inner end of the extension substantially to the outer end thereof, there being a shoulder 20 at the junction of the bore 18 with the hole 16. The body portion 12 of the housing 10 is provided with a counterbore 22 which is coaxial with and communicates with the bore 18, an annular shoulder 24 being formed at the junction of. the counterbore 22 with the bore 18.

With this construction, the housing 10 may be bored out from one end thereof in a single operation, the hole 16, the bore 18 and the counterbore 22 being formed simultaneously with a three-step boring tool, which is an important feature. The open end of the counterbore 22 is closed by a cover 26 which is attached to a flange 28 on the pump housing 10 by means of screws 30, or the like, a gasket 32 being interposed between the flange 28 and the cover 26 to prevent leakage.

Disposed in the counterbore 22 on one side thereof and suitably secured in place, as by a screw 34, is a cam 36, the space in the counterbore 22 which is unoccupied by the cam 36 constituting an impeller chamber 38.

Disposed in the impeller chamber 38 is a rubber impeller 40 having a hub 42 which is provided with a closed end and which carries radial vanes 44 whose ends engage the shoulder 24 and the cover 26, respectively, and whose outer edges engage either the inner surface of the cam 36, or the peripheral wall of the counterbore 22. The vanes 44 are periodically flexed by the cam 36 as the impeller 40 is rotated in the impeller chamber 38 so as to produce the desired pumping action, as is well known in the art.

Considering the manner in which the impeller 40 is rotated in the impeller chamber 38, extending through the hole 16 and the bore 18 into the impeller chamber 38 is a shaft 46 which is supported by a bearing 48 in the bore 18 intermediate the ends thereof. The bearing 48 includes an outer race 50 fitting in the bore 18 and includes one or more annular rows of balls 52 which engage the outer race and the shaft 46, the latter thus serving as an inner race for the balls 52. The shaft 46 and the bearing 48 constitute a unit of the type commonly used in automotive fan and water pump combinations, such units being extremely reliable and being inexpensive, thereby minimizing the cost of the pump of the invention.

The shaft 46 is provided at its inner end, within the impeller chamber 38, with one or more recesses 54. The recess or recesses 54 may either be chordal recesses or keyway-like grooves, as disclosed in said application Serial No. 447,163, or may be recesses of arcuate cross section, as disclosed in said application Serial No. 445,837. Alternatively, other recesses may be used.

The impeller 40 is provided with a central impeller insert 56 onto which the impeller is molded, the insert 56 being shown as a tube or sleeve telescoped onto the shaft 46 and being provided with one or more inwardly struck dimples 58 respectively disposed in the recesses 54 to transmit rotation of the shaft to the impeller. With this construction, the impeller 40 may be installed on and removed from the shaft 46 readily, as more fully discussed hereinafter and in the aforementioned copending applications.

The pump of the invention includes a sealing means 60 for preventing, or substantially preventing, leakage along the shaft 46, both from the impeller chamber 38 and from the bearing 48. The sealing means 60, which is disposed in the bore 18, is shown as including three seals or

sealing elements

62, 64 and 66, the

seals

62 and 64 being referred to hereinafter as primary and sec-.

ondary seals, respectively. In the particular construction illustrated, the sealing elements'62, 64 and '66 'are lip seals the lips of which are biased inwardly by annular springs 68.

The primary seal 62 engages the peripheral wall of the bore 18 and the lip thereof engages an extension 70 of the impeller insert 56, thereby preventihg wear o'f the shaft 46 due to the presence of the seal, this beingpar-.

ticularly important where abrasives-arepre'sentjin'ithe material being pumped, as disclosed in said application Serial No. 447,163. The seal 62 is biased toward-"the impeller 40 by a spring 72 which also engages the sec'- ondaryseal 164 to bias it toward the bearing 48. The secondary seal 64 also engages the impeller-insert extension 70, the pump-housing extension 14 being provided with bleed holes 74 which communicate with the space between the

seals

62 and 64 and through which any fluid leaking past the primary seal 62 may be drained off. Fluid leaking past the seal 62 cannot leak past the seal 64, both because the bleed holes 74 prevent the development of'apressure differential across the seal 64 in a direction toproduce. such leakage, and because of the presence of. grease, or other lubricant, in the bearing 48 between the

seals

64 and 66. Consequently, since fluid leakage past the primary seal 62 cannot pass the secondary seal 64, none of the fluid being pumped can seep between the impeller insert 56 and the shaft 46, entry of fluid therebetween from the other end of the insert being lprevented by the hereinbefore-mentioned closed end of the impeller hub 42. As a result, the fluid being pumped cannot cause the insert 56 to stick to the shaft 46 in any manner, as by rusting or otherwise corroding the shaft and/or insert, for example. Therefore, the impeller 40 can always be removed from the shaft 46 readily for replacement, which is an important feature. Also, since the shaft can never be damaged by the fluid being pumped, as by rusting or corrosion, its life is greatly prolonged. Further, any wear of the shaft due to the presence of the seals 62 and- 64 is eliminated, thereby further prolonging the shaft life.

The seal 66 is located at the opposite end of the hearing 48 from the seal 64 and is retained in the bore 18 by the aforementioned shoulder 20, the

seals

64 and 66 cooperating to retain a=-lubricant in the bearing. It will be noted that the seal'66 engages the shaft 46 directly, but. since this seal is lubricated and is not exposed to any abrasives carried by the fluid being pumped, it willcause shaft wear at an insignificant rate. a

Fig. 2 of the drawing illustrates a construction wherein the primary seal 62, instead of being disposed directly in the bore 18, is disposed in a counterbore 80 interposed between the bore 18 and the counterbore 22. An annular shoulder 82 for retaining the seal 62 is formed by the junction of the counterbore 80 and the bore 18. It will be understood that the counterbore 80 may be formed simultaneously with the hole 16, the bore 18 and the counterbore 22 with a suitable multiple-step boring tool.

As will be apparent, any of the parts of the pump of the invention may be replaced readily if necessary. For example, the impeller 40 may be removed readily mercly by removing the cover 26 and pulling the impeller oil the shaft 46, the torque-transmitting connection shown, and the prevention of rusting or corrosion between the insert 56 and the shaft, permitting ready removal of the impeller from the shaft. Also, the seals and the bearingshaft unit may be removed readily in a manner which will be apparent.

Although I have disclosed an exemplary embodiment of my invention herein, it will be understood that various minor changes, modifications and substitutions may be incorporated therein without departing from the spirit of the invention as defined by the patent claims appearing hereinafter.

I claim as my invention:

1. In a pump, the combination of: a pump housing including a body portion having an axial extension at one end thereof, said body portion providing an impeller chamher and said extension being provided with a bore having an inner end in open communication with said impeller chamber and having an outer end axially spaced from said inner end thereof, said extension being further provided with a hole coaxial with said bore and communieating with said outer end of said bore and of smaller diameter than said bore to provide an annular shoulder; a shaft extending through said hole and said bore into said impeller chamber; an impeller on said shaft in said impeller chamber; a-torqu'e-transmitting connection between said shaft and said impeller; a bearing for said shaft in said bore between said inner and outer ends of said bore; and seals in said bore on opposite sides of said a bearing and engaging said extension and said shaft for said impeller insert having an extension projecting axially beyond one end of said impeller toward said bearing housing; a torque-transmitting connection between said shaft and said impeller insert; an impeller in said impeller housing and carried by said impeller insert; a bearing in said bearing housing and encircling said shaft; and two seals in said housing structure between said impeller and said bearing and engaging said housing structure and said impeller-insert extension, said housing structure having a drain between said seals.

3. A pump according to claim 2 including a third seal in said housing structure on the opposite sideof said hearing from the first two seals mentioned and engaging said housing structure and said shaft.

References Cited in the file of this patent UNITED STATES PATENTS 2,150,078 Pollock Mar. 7, 1939 2,246,279 Wishart June 17, 1941 2,573,819 Weyer Nov. 6, 1951 2,649,052 Weyer Aug. '18, 1953 2,666,394 Sadler et a1. Jan. 19, 1954 2,688,930 De Moss Sept. 14, 1954