US 3137240 A
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Description (OCR text may contain errors)
United States Patent 3,137,240 PUMPS Russell G. Hunt, 1308s. Shelley, Santa Ana, Calif. Filed July 17, 1961, Ser. No. 124,692 2 Claims. (Cl. 103-149) This invention pertains to new and improved pumps. More specifically this invention pertains to what may be termed tube pumps inasmuch as each of such pumps utilizes an elastomeric tube in conjunction with means for compressing this tube in order to achieve a pumping action. Many different specific designs for pumps of this generalized type have been created in the past. As a general rule such prior tube pumps have utilized a rotor 1n order to compress the tube in order to achieve a pumping action. Tube pumps of the broad category indicated in this paragraph are commonly used in order to create a vacuum for various purposes in chemical fields inasmuch as with pumps of this type there is no danger of contamination of the material within the tube and inasmuch as most elastomeric tubes are relatively inert with respect to many common types of chemical solutions.
Although tube pumps as the term is used in the preceding paragraph are well known, there is a definite need for improvement in pumps of this category. To a large extent this need is for pumps of the category described which are relatively simple to construct, easy to maintain, and which are capable of operating satisfactorily over prolonged periods whenever this is desired, and which can be used either intermittently or continuously as required for any specific operation. A broad object of the present invention is to provide pumps that satisfy this need.
A more specific object of this invention is to provide new and improved pumps of a tube pump category as explained in the preceding which can be operated satisfactorily for prolonged periods at a comparatively nominal cost with a minimum of maintenance. Other objects of this invention are to provide tube' pumps as described which may be conveniently used in order to handle various corrosive liquids such as chlorine solutions without difiiculty, and which are capable of being employed as suction or vacuum pumps during such use. A related object of this invention is to provide new and improved pumps of the type indicated which are relatively inexpensive to manufacture.
These and various other objects of this invention as well as many specific advantages of it will be more fully apparent from a detailed consideration of the remainder of this description, the appended claims and the accompanying drawing in which:
FIG. 1 is a perspective view of a pump of this invention;
FIG. 2 is a cross-sectional view taken at line 22 of FIG. 1;
3,137,240 Patented June 16, 1964 shaped cavity. With a pump of this invention an elastomeric or flexible tube extends around the periphery of the cavity and means are attached to the shaft so as to periodically compress the portions of the tube within the interior of the cavity itself. The pumps of the present invention also include a number of specific features which are utilized in this generalized construction so as to achieve the preceding objectives of the present invention.
These features are best explained by referring directly to the accompanying drawing in which a pump 10 of this invention is illustrated. This pump 10 includes a horizontal base 12 which carries a vertical, upstanding wall 14. On the back side 16 of this wall 14 a small speed reducing gear box 18 is secured to the wall 14 by means of screws 20. Other screws 20 are used to hold a small electric motor 22 upon the gear box 18. The shaft 24 forming a part of this motor 22 carries a small fan blade 26; this shaft 24 extends into the gearbox 18 so as to supply power to this gear box. Power is taken from the gear box by means of a shaft 30 extending through a centrally located hole 32 in the wall 14 so as to terminate on the front side 34 of this wall 14.
Preferably a small housing 36 for protective purposes is mounted upon the back side 16 of the wall 14 so as to surround the gear box 18 and'the motor 22. This housing 36 may conveniently be provided with ventilation holes 38 and another hole 40 adapted to enable electrical wires 42 to extend from the outside of the pump 10 to the motor 22 for the purpose of operating this motor.
The front side 34 of the wall 14 is formed so as to include a housing Wall 44 having an internal cylindrical surface 46 formed therein. This surface is intersected by passages 48 and 50 which extend at a right angle to the base 12 away from this base through the housing wall 44. The passage 48 extends tangentially from the surface 46. As shown in FIG. 3 of the drawing preferably these. passages 48 and 50 are parallel to one another and are located so as to be spaced so as to intersect the surface 46 at an angle of less than 180 around the axis of the surface 46 and of the shaft 30.
This construction is designed so that a flexible, elastomeric tube 52 of substantially uniform diameter may be located in order to extend through the passage 50 so as to extend more than 180 around the axisof the surface 46 and the shaft 30. The purpose of this particular construction will be made fully described hereinafter. If desired, the edge 54 of the intersection of the passage 50 and the surface 46 where the tube 52 is bent may be curved slightly so as to avoid undue wear upon this tube.
In the pump 10 the tube is periodically compressed through the utilization ofmeans for compressing this tube consisting of a rotor 56 which is secured to the shaft 30 FIG. .3 is a cross-sectional view taken at line 33 of .the design and construction of pumps will realize that other differently appearing pumps may be easily constructed on the basis of the disclosure embodied within the accompanying drawing and within this description so as to utilize the inventive features defined in the appended claims.
As an aid to understanding this invention it can be stated in essentially summary form that it concerns pumps or tube pumps, each of which utilizes a motor in order to rotate a shaft which extends axially within a discso as to rotate with respect to it and by means of spools 58 which are rotatably mounted upon this rotor 56. Preferably the rotor 56 includes bifurcated ends 60 which hold small axles 62 which in turn rotatably carry the spools 58. Preferably these spools 58 are formed out of a material having low friction properties such as nylon, polytetrafluoroethylene or the like, so that rotation between them and the axles 62 may be achieved with a minimum of difiiculty. As will be seen in FIG. 2 of the drawing the spools 58 include end flanges 64 which straddle the tube 52 during the compression of this tube so as to aid in maintaining the tube in a correct position against the surface 46.
gasket 76 which is disposed in'a groove 72 of the housing 5 wall 44 so as to resiliently-bear against the plate 66 and the wall 44. The plate 66 also preferably includes a small oil opening 74 which is located with respect to the interior so as to lead into the interior of the disc-shaped satisfactory prolonged operation of the pump by minimizing the tendency for wear with respect to the tube 52. In order to achieve preferred results of the present invention the body liquid lubricant 76 should consist of an oil or an oil mixture which is substantially inert with respect to the material from which the tube 52 is made, and which is capable of exercising a lubricating effect with respect to this tube. It is presently preferred to utilize in the pump 16 a tube 52 formed out of a surgical grade rubber latex having comparatively thick walls and to utilize with this tube 52 castor oil since this oil does not affect this specific elastomeric type material as by causing swelling or the like and is capable of exercising a lubricating function with respect to this elastomeric material. a
As can be seen in FIG. 2 of the drawing, the body 76 is located within the wall 44 generally below the sealing opening 74 when the pump 111 is orientated as shown in the drawing. When, however, it is desired to mount the pump 11 at another angle than the specific angle shown with the specific structure illustratedthis can be done pro- 7 vided the body 76 is maintained within the interior of the wall 44 so that it does not tend to flow out of either of the passages 48 or 50. As an example of this, the pump 10 illustrated can be mounted at a right angle to the position in which it is shown in the drawing so that the body of oil 76 assumes the position having a surface level as designated by the dotted line 78 in FIG. 2 of the drawing. From a consideration of this it will be realized that the passages 48 and 56 are spaced with respect to one another as. described in the preceding in order to permit the pump 10 to be mounted in either a horizontal position as shown or in a vertical position in which the body 76 has a surface following the line 78.
During the operation of the pump 10 relative movemerit between the tube 52 and the wall 44 will normally tend to take place so as to tend to move the tube 52 around the interior of the surface 46. A retainer 80 as indicated in FIG. 4 of the drawing is employed so as to prevent any tendency of the tube 52 to move in this manner. This retainer 80 may be secured to the housing wall .44 by means of a further screw 20 so as to cover the surface of this wall 44 remote from the wall 14 which is not covered by the plate 66. The retainer 80 preferably includes ridges 82 which fit within the passages 48 and 50 so as to resiliently engage the tube 52 without collapsing it. An efiicient holding action is achieved by utilizing on these ridges 82 small serrations 84 which extend generally across the passages 48 and 50. Similar serrations 84 may be located in the bottoms of the passages 48 and 50 opposite the ridges 82.
From a consideration of the foregoing it will be realized that the pump 10 shown is comparatively inexpensive to manufacture for a number of different reasons. One ofthese is that in this pump 10 the wall serves a double purpose, while simultaneously serving as support Wall for the gear box 18 and the motor 22. In effect this wall 14 eliminates a separate wall used for motor mounting and other purposes in other prior constructions. It will be further realized that the base 12, the Wall 14 and the wall 44 may all be formed as an integral unit by known casting or similar molding procedures with a minimum of difficulty.
The foregoing and related factors are, of course, important. The ability of pumps such as the pump 10 to be used over prolonged periods is also, however, extremely important. With a structure formed as the pump 10 the amount of wear upon the tube used is effectively minimized, even if a body of lubricant such as the body 76 is not employed. The utilization of a body of oil such as the body 76 is considered to materially increase the ability of a pump such as the pump 10 to be operated satisfactorily over a prolonged period. It'is considered that this has been demonstrated by tests with pumps similar to the pump 10 which have been utilized for vacuum purposes-in dispensing quantities of a chlorine solution for swimming pool purposes. 7 This advantage of the use of a body of oil is achieved in the pump 10 in a very simple, effective structure capable of being used in various positions.
Those skilled in the art to which this invention pertains will realize that pumps such as the pump 10 may, of course, be modified in a number of different ways in accordance with routine engineering skill. Because of this present invention is to be considered as being limited only by the appended claims forming a part of this disclosure.
I claim: 1. A pump which includes: housing means having an internal disc-shaped cavity having ends formed therein, said cavity having an axis and including two passages located so as to lead into the interior of said cavity, said housing means further including slots laterally communicating with said passages; an elastomeric tube positioned so as to extend through each of said passages andaround more than half of and less than the entire periphery of the interior of said cavity;
means for compressing said tube so as to close said tube mounted within the interior of said cavity so as to be capable of being rotated about said axis, said means for compressing including rotor means rotatably mounted within said cavity and a plurality of spools rotatably mounted on said rotor means so as to be rolled along said. tube within said cavity during rotation of said rotor means, said spools having flanges thereon, said flanges being axially spaced on said spools and being axially spaced from the axial ends of said cavity so that at least one of said flanges engages with said tube when tube is compressed by said spools;
means for rotating said means for compressing operatively associated with said means for compressing;
a body of oil located within said cavity so as to cover at least part of said tube, said tube being inert with respect to said oil; and
a retainer carried by said housing means, said retainer including friction surfaces extending through said slots into engagement with said tube.
2. A pump as defined in claim 1 wherein said friction surfaces or in said retainer are serrated in such a direction as to resist motion of said elastomeric tube through said passages.
References Cited in the file of this patent UNITED STATES PATENTS 2,015,123 Pennell Sept. 24, 1935 2,428,619 Douglas Oct. 7, 1947 2,434,802 Jacobs Jan. 20, 1948 2,651,264 Bruckmann Sept. 8, 1953 2,897,767 Cordis Aug. 4, 1959 2,899,904 Becher Aug. 18, 1959 2,975,719 Kaufman Mar. 21, 1961 FOREIGN PATENTS 628,785 Great Britain Sept. 5, 1949