EP0537128B1

EP0537128B1 - Pump

Info

Publication number: EP0537128B1
Application number: EP92850211A
Authority: EP
Inventors: Steve Ericson; Wallace W. Ericson
Original assignee: ERICSON SAFETY PUMP Corp
Current assignee: ERICSON SAFETY PUMP Corp
Priority date: 1991-10-09
Filing date: 1992-09-09
Publication date: 1996-05-22
Anticipated expiration: 2012-09-09
Also published as: JPH05195992A; IL103095A0; EP0537128A3; NO923869L; DE69210937T2; BR9203887A; IL103095A; CA2077582A1; NO923869D0; EP0537128A2; DE69210937D1; ATE138451T1; ES2087504T3; GR3020052T3; DK0537128T3

Abstract

A centrifugal pump having an impeller (38) which is associated with a motor and a drive shaft (16,14) and that is enclosed within a housing (28). The housing (28) is mounted in surrounding, spaced and non-contacting relationship, with respect to the impeller (38) and drive shaft (14) contains fluid inlet (26,26') through which fluids are directed by the impeller (28) to an outlet from the housing (28). Also provided is a pump which operates from remote locations.

Description

Field of the Invention

This invention is generally directed to centrifugal pumps having rotatably driven impellers mounted within a housing so as to create a fluid flow through such housing between an inlet and an outlet therein. More particularly, the invention provides a centrifugal pump which includes an impeller that couples an engine to a drive shaft and is rotatably disposed within the housing. Opposing fluid inlets are created between the sides of the housing and the drive shaft from which fluids are directed to a fluid outlet also formed in the housing.

Background of the Invention

U.S. Pat. No. 4,688,987 to Ericson et al discloses a centrifugal pump having a split impeller which is mounted directly to an existing drive shaft. The inner surfaces of the hub portions of the split impeller are knurled or otherwise provided with ridges as to bite or lock the hub against the drive shaft when the two portions of the impeller are joined together.
This prior centrifugal pump is particularly adapted for use in the engine compartment or hull of a marine vessel wherein the impellers is attached for rotation with the drive shaft, such as a propeller drive shaft, and wherein the pump housing is mounted so as to be in a surrounding and spaced relationship to the impeller blades and drive shaft. The impeller is freely rotatable in order to pump fumes or fluids through annular intake openings between the drive shaft and pump housing and deliver the same through an outlet formed in the pump housing.
It is an object of this invention to provide a self priming centrifugal pumping apparatus which couples an engine and a drive shaft in an environment wherein hazardous gases or fumes may be encountered and wherein the pump is structured so that the gas or fluid impeller is not journaled or directly mounted to the pump housing. In this mannert no heat is generated during the rotation of the impeller by friction between the impeller and the housing as is the case in a pump in which the impeller is directly carried by the pump housing.
It is also an object of the present invention to provide a centrifugal pump apparatus which is coupled between the engine and the drive shaft to provide a pumping apparatus which does not require the lubrication and maintenance associated with conventional centrifugal pumps.

Summary of the Invention

According to the present invention there is provided a self priming centrifugal pump apparatus as defined in claim 1 for use in an atmosphere subject to the build-up of hazardous gases or other fluids .
The apparatus comprises a drive shaft, an engine or motor for driving said drive shaft, a housing having front and rear walls, a peripheral side walls and, fluid inlet openings which surround the power source and provides equal pressure from both sides on an impeller. Mounting means is provided for securing the housing so as to be in a fixed, spaced and non-contacting relationship around the drive shaft. An impeller means which is sloped on two sides forms a coupling of the motor with the drive shaft within and in spaced relationship with the housing. The slope expedites movement of the liquid outward to the vanes. Accordingly, the impeller and housing cooperate to discharge hazardous fluids in response to the rotation of the drive shaft without any substantial generation of heat due to friction.
According to one embodiment of the invention, the housing comprises front, rear and side wall portions at least, a pair of opposing fluid inlet openings in said front and rear walls of said housing providing equal pressure from both sides on the impeller means, each of said fluid inlet openings being of a greater dimension than said first cross sectional dimension of the drive shaft. The housing is provided with at least two sections which are divided along lines which intersect with the fluid inlet openings. Means is provided for selectively uniting the sections so as to enclose a portion of the length of the drive shaft therebetween and through each of the fluid inlet openings.
The drive shaft according to this embodiment extends through fluid inlet openings in spaced non-contacting relationship to the housing so that fluids entering the housing under equal pressure, passes around the drive shaft, along the sloped impeller to the impeller blades that propel the fluid outlet opening.
Preferably, the discharge opening is formed in the side wall of the housing and includes a nozzle means for creating a channel which extends outwardly of the housing generally tangentially with respect to the side wall portions.
Accordingly, to another embodiment, the housing defines a generally cylindrical chamber and the blade means of the impeller means substantially extends between the front and rear walls of the housing and outwardly into proximate relationship with the side wall portions thereof. The walls of the housing include portions extending outwardly beyond the walls, with spacer means extending from the outwardly extending portions of the rear walls so as to space the housing from adjacent walls of the enclosure.
The sloped impeller is formed within the housing by the coupling of the motor to the drive shaft. The impeller may be formed by the coupling of the motor to the drive shaft or it can be in the form of a blade means which couples to the motor and to the drive shaft.
The pump may be used by itself to carry a liquid from a vessel or container or can be used in combination with the drive shaft of a propeller for a boat to remove fumes.

Brief Description of The Drawings

Fig. 1 illustrate the mounting of the pump of the invention with the propeller drive shaft and transom of an inboard motor;
Fig. 2 is an enlarged front plan view of the pump housing taken along lines 2-2 of Fig 1;
Fig. 3 is a side view of the sloped impeller taken along lines 3-3 of Fig. 2; and
Fig. 4 is a cross-sectional view taken along lines 44 of Fig 3.

Description of the Preferred Embodiment

A more complete understanding of the invention will be had by referring to the following description and claims of a preferred embodiment, taken in conjunction with the accompanying drawings, wherein like reference members refer to similar parts throughout the several views.
With continued reference to the drawings, the centrifugal pump 12 of the present invention is shown as it is mounted in relationship to a propeller drive shaft 14 within the hull of an inboard motorboat 10. The drive shaft 14 is shown in Fig. 1 as extending from the propeller 20 though a transom, to the motor or engine 18. A suitable bearing or stuffing box 22,22' is mounted so as to rotatably support the drive shaft 14 and pump 12. It should be noted that although the centrifugal pump 12 is being described for use with the propeller drive shaft of a conventional inboard motorboat 10, the pump 12 could be used in other environments. In addition, although only a single pump 12 is shown in the preferred embodiment, there may be occasions when two or more pumps would be-used in the same environment such as a boat having twin screws driven by a pair parallel drive shafts.
As shown in Figs 2 and 3, the pump 12 is essentially constructed of an impeller 38, comprising a bladed member 38A which forms a coupling with the end coupler 16A of the engine 18 and the end coupler 38 of the drive shaft 14, and a housing 28. The pump housing 28 can be integral or split and composed of upper and lower sections, a circular or semicircular sidewall, a front wall and generally rectangular rear wall as found in U.S. Pat. No. 4,688,987. Openings 26, 26' are provided in the upper corners of the rear wall of the upper section and through the lower corners of the rear wall of the lower section through which mounting bolts 34 may be selectively extended.
In order to create the desired suction and discharge at the inlet and discharge areas 23 of the housing, the impeller blades 32 are constructed to substantially extend outwardly to a point in close proximity with the inner surfaces of the sidewalls. Additionally, the width of the blades 32 is substantially equal to but slightly less than the distance between the front and rear walls. The design of the impeller 38 and pump housing 28 is such that upon rotation of the drive shaft 14, the impeller 38 will simultaneously be rotated to thereby draw air, fumes, liquids or other fluids inwardly through the opposing openings 26, 26'. Thereafter, the fluids move along the sloped surface of the impeller 38 and are discharged under pressure through the passageway in the discharge areas 23 and through the exhaust hose 24 or similar conduit to a point remote from the pump.
When the engine is activated to rotate the drive shaft, the impeller rotates within the pump housing thereby drawing fluids including liquids and gases through the inlet ports and thereafter discharging- the fluids under pressure through the outlet nozzle.
Therefore, the centrifugal pump of the present invention will automatically function to discharge any hazardous gaseous or fluid buildup or generated due to friction and thus the pump is sa fe for use in environments where ignitable or combustible fluids or gases are encountered.
Although the impeller means 38A is shown in Fig. 3 as being a separate and single intermediate bladed member 38A having a series of steps 31 which are in mating engagement with the end member 14A of the drive shaft 14 on one side and the steps 31A of the end member 16A of the shaft 16 of the engine 18, the bladed impeller means 38A can also be integral with either end member 14A or end member 16A. Therefore, there can be a coupling to both sides of the impeller 38 within the housing or one side.
Fig. 4 shows the sloped coupled impeller 38 which is held together by bolts 34 or any other fastening member. The slope expedites movement of the liquid from the center of the impeller to the blades 32 where it is rapidly discharged through the outlet. A 30 to 45° slope on the impeller 38 is generally suitable for moving the liquid to the blades 32.
The pump of the invention does not require great precision in manufacture therefore it can be formed from metals such as aluminum, bronze, etc., or rigid plastics such as RYTON. (registered trade mark).
Although the foregoing invention has been described in some detail by way of illustration and example for purposes of clarity of understanding, it will be obvious that certain changes and modifications may be practiced within the scope of the appended claims.

Claims

A self priming centrifugal pump apparatus (12) for use in an atmosphere subject to the build up of hazardous gases or other fluids, comprising a drive shaft (14), a motor means (18) for driving said drive shaft, a housing (28) having front and rear walls, peripheral side walls, a discharge outlet opening (23,24), mounting means for securing said housing so as to be in a fixed, spaced and non-contacting relationship around the drive shaft, impeller means (38A) within and in spaced relationship with said housing (28), said impeller means having outwardly extending blades (32), and inlet means (26,26) about the drive shaft (14) so that fluid moves outwardly to the blades, whereby the impeller means (38A) and housing (28) cooperate to discharge fluids through said outlet opening in response to the rotation of the drive shaft without any substantial generation of heat due to friction and the inlet means permits entry of the fluids so that there is equal pressure on both sides of the impeller means, characterized by said impeller means (38A) having the blades (32) at its periphery and being sloped so as to widen the space within said housing (28) with increasing radial distance from the drive shaft (14) and further being formed by a coupling of said motor means (18) to the drive shaft (14).
The centrifugal pump apparatus of claim 1 wherein said housing (28) comprises front, rear and side wall portions, a pair of aligned fluid inlet openings (26,26') in said front and rear walls of said housing, each of said fluid inlet openings being of a greater dimension than said first cross sectional dimension of the drive shaft (14).
The centrifugal pump apparatus of claim 2 wherein said drive shaft (14) extends through said fluid inlet openings (26,26') in spaced non-contacting relationship to said housing (28) so that fluids entering said housing (28) passes around said drive shaft (14) substantially equally on both sides of the impeller means, across the sloped surface of the impeller means (38A) and through said outlet opening (23,24).
The centrifugal pump apparatus of claim 2 in which said discharge opening (23,24) is formed in said side wall of said housing (28) and includes a nozzle means for creating a channel which extends outwardly of said housing generally tangentially with respect to said side wall portions.
The centrifugal pump apparatus of claim 1 in which said housing (28) defines a generally cylindrical chamber, said impeller means (38A) has blade means (32) substantially extending between said front and rear walls of said housing (28) and outwardly into proximate relationship with said side wall portions thereof said rear walls of said housing include portions extending outwardly beyond said walls, and spacer means extending from said outwardly extending portions of said rear walls so as to space said housing from adjacent walls of the enclosure.
The centrifugal pump apparatus of claim 1 wherein said drive shaft (14) is coupled to one side of said impeller means side, said motor means (18) is coupled on the other side of said impeller means (38A) within said housing (28), and said drive shaft (14) is provided with propeller means (20).
The centrifugal pump apparatus of claim 1 wherein said impeller means (38A) has a slope on both sides of about 30 to 45 degrees.