US3360190A

US3360190A - Fuel pump assembly

Info

Publication number: US3360190A
Application number: US478248A
Authority: US
Inventors: Robert W Erikson; Nils E Swedberg
Original assignee: Sundstrand Corp
Current assignee: Sundstrand Corp; Suntec Industries Inc
Priority date: 1965-08-09
Filing date: 1965-08-09
Publication date: 1967-12-26
Anticipated expiration: 1984-12-26

Description

1967 R. w. ERIIKSON ETAL 3,360,190

FUEL PUMP ASSEMBLY Filed Aug. 9, 1965 2 Sheets-Sheet l 1967 R. w. ERIKSON ETAL 3,360,190

FUEL PUMP AS SEMBLY Filed Aug. 9, 1965 2 Sheets-Sheet 2 United States Patent 3,360,190 FUEL PUMP ASSEMBLY Robert W. Erikson and Nils E. Swedberg, Rockford, Ill.,

asslgnors to Sundstrand Corporation, a corporation of Illinois Filed Aug. 9, 1965, Ser. No. 478,248 6 Claims. (Cl. 230-139) ABSTRACT OF THE DISCLOSURE This invention relates to oil burner apparatus and more particularly to an oil burner subassembly including a pump, an air blower fan, and a motor for driving both, all assembled together in a single package.

In oil burner installations, a pump is conventionally provided for supplying fuel to nozzles in a combustion chamber. Also, a fan or blower is usually provided in an air duct for supplying forced air to the combustion area adjacent the burner nozzles. In the past, these components, ie, the pump and the fan, have been connected with an electric motor to be driven thereby. However, these prior units have usually been bulky, space-consuming and expensive to manufacture. In instances where simplified constructions have been attempted, these units lacked the necessary drive shaft support and alignment which oftentimes made them unsuitable for extended use without repair. One of the problems that has handicapped the design of a simplified pump-motor-fan assembly of this type is the difliculty in aligning and coupling the pump, motor and fan shafts while maintaining the proper bearing support for each.

According to the present invention, these problems are overcome and a new and improved oil burner pump assembly or package is provided by employing a single shaft connected with the motor rotor for driving both the pump and the fan. This overcomes the problem of a multiple shaft misalignment and coupling noted above. The unitary shaft is properly and accurately supported at one end in the motor housing and at the other end Within the pump housing thereby eliminating the necessity for multiple motor housing bearings. The pump is accessiblyv mounted outside the motor housing at one end thereof to provide a compact unit with the shaft bearing in the pump housing closely adjacent the motor housing to provide effectively the same unsupported motor shaft length as would result in a construction with multiple motor housing bearings. There is also provided a novel means for locating the pump housing bearing coaxial with the motor housing bearing. The blower fan encircles the motor elements to provide a compact structure and ,to cool the motor elements.

It is, therefore, a primary object of the present invention to provide anew and improved oil burner pump, motor and fan assembly of compact and simplified construction while maintaining the necessary support for the rotating elements of the assembly.

Another object of the present invention is to provide' a new and improved oil burner pump, motor and fan assembly of the type described wherein the rotary elements of the assembly are supported ona single drive shaft.

A further object of the present invention is to provide a new and improved oil burner assembly of the type described above wherein the pump is mounted outside and 3,360,190 Patented Dec. 26, 1967 at one end of the motor housing and provides bearing support for one end of the unitary drive shaft, the other end of the drive shaft being supported in a bearing in the opposite end of the motor housing.

A still further object of the present invention is to provide a new and improved-oil burner assembly including a pump, motor and fan of the type described above in which the-motorvhousing has two coaxial bores.

susceptible of machining during the same setup, one of the bores receiving one end of the drive shaft, and the other bore serving as a receiving and locating bore for a pilot extending from the pump housing so that the pump housing is accurately located with respect to the motor housing bearing and in which the pump has a porting member With a central bore therein defining the bearing for the other end of the drive shaft, the port member being accurately located with respect to a central shaft receiving bore in the pump housing by an alignment sleeve, so that the shaft bearing in the port plate is accurately aligned with the bearing in the motor housing.

Other objects and advantages will be readily apparent from the following detailed description taken in connection with the accompanying drawings, in which:

FIG. 1 is a side elevation of a pump, motor and fan assembly incorporating the principles of the present 'invention;

FIG. 2 is an end elevation of the assembly shown in FIG. 1 illustrating the pump and mounting flange configurations; and

FIG. 3 is a longitudinal section, of the assembly shown in FIG. 1.

While this invention is susceptible of embodiments in many different forms, there is shown in the drawings and will be described herein in detail an embodiment of the invention with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the invention to the embodiment illustrated. The scope partially in elevation,

of the invention will be pointed out in the appended claims.

Referring now to the drawings and particularly FIGS.

1 and 2, the present oil burner assembly, generally designated by the numeral 10, is seen to consist of a one.-

. stage gear pump 11, a sirocco fan or blower 12 anda motor -13, shown more clearly in FIG. 3. The pump 11 is an oil burner pump which may take the form generally shown in the Erikson et al. Patent 2,931,314. For this reason, the details and operation of the pump are not described in detail herein except for the drive shaft mounting arrangement described below with reference to FIG. 3.

An annular mounting projection 15 formed integrally. 'with the housing of the motor serves to support the assem-.

-bly within an air duct (not shown) leading to the oil burner. An annular mounting flange 16 formed integrally thereon with projecting mounting ears 17 engages one side of the air duct; and with suitable fittings through the ears 17, the assembly is supported on the duct. The fan 12,.

and a portion of the motor which is circumscribed by the fan, project within the air duct, i.e. the portion of the assembly to the right of flange 16, as viewed in FIG. 1. The mounting projection 15 and the pump 11 are adapted to project externally from the air duct. As the motor rotates the pump 11 and the fan 12, fuel oil is supplied to the oil burner (not shown) by pump 11 and forced air is supplied to the burner by the fan or blower 12 through the duct.

For the purpose of describing in more detail the construction of the assembly 10, reference is made to FIG. 3

I wherein the motor housing is seen to consist of generally manner, the periphery of the stator 22 is open and may be 3 cooled by air entering the blower 12 axially from the right, as shown in FIG. 3. The cup-

shaped members

19 and 20, and particularly the former, may have suitable openings as at 23 to conserve material and to improve the cooling of the motor elements.

The mounting member is formed integrally with the left housing member and extends approximately to the diameter of the fan or blower 12.

A unitary drive shaft 26 carries a rotor motor element 27 affixed thereto. This shaft is supported at its right end in a bearing assembly 28 mounted within the central portion of cup-shaped motor housing member 19. Bearing assembly 28 consists of a sleeve bearing 30 of porous bronze pressed into the hub of housing member 19, together with lubrication communicating with the inner surface of bearing 30 to provide lubrication to the drive shaft 26. Lubricating oil is supplied to the assembly 28 through a suitable conduit 35, one end of which is mounted within the central portion of housing member 19. Conduit communicates with an annular felt ring 31 fitted in a recess in housing member 19 around the shaft 26 and a portion of the bearing sleeve 30. The felt ring 31 is held in place by a retainer ring 32 as of metal around the shaft 26 and frictionally held in the housing member 19. Felt ring 31 touches a half ring 33 of felt of a radial thickness as shown, and the half ring 33 in turn engages a body of felt 34. The body 34 has a radially outer surface concentric about the shaft 26 and of a radius as shown, and has a chordal lower or inner surface tangent to the shaft 26 as shown. The lower portion of the body 34 fits in a recess in the bearing sleeve 30 in order to make line contact with the shaft 26. By virtue of the arrangement described lubricating fluid from the tube 35 is absorbed by the various felt members illustrated and the outer surface of the shaft 26, as well as the inner surface of the sleeve 30, is lubricated.

A thrust bearing ring 36 is retained on the shaft 26 by a snap ring 37, and the ring 36 engages the end of the hub 19a in the housing member 19, as well as the end of bearing sleeve 30. In order to lubricate the inner engaged surfaces of the members 19a, 30 and 36, another body of felt is provided as at 38. The latter has an approximately semi-circular shape and contacts the felt ring 31 to convey lubricating fluid from the ring 31 to the vicinity of the surface of the thrust ring 36 where the latter engages the housing hub 19a. The hub 19a also carries an annular collector ring 39 lined with felt as at 39a in order to collect any lubricating fluid that might be thrown from the shaft and bearings.

The right end of drive shaft 26 extends from bearing assembly 28 outwardly of the motor housing member 19 {and has keyed thereto a hub 34 forming a part of the fan assembly 12. In this manner, fan 12 is supported and driven by the drive shaft 26. It should 'be understood that with this construction, it is possible to easily change fans merely by unfastening and removing the hub 34 and fan from the right end of shaft 26 and replacing it with different fan. In this regard the present construction is usable with different sized fans of conventional construction.

The pump has a housing member 40 with projecting mounting ears 41 and 42 thereon (shown more clearly in FIG. 2) which receive Wasteners that fix the pump housing on the left generally vertical mounting boss 43 formed on the outside of motor housing member 20. The

housing 40 has an axially extending pilot 44 received in a locating bore 46 in motor housing member 20. Bore 46 and pilot 44 serve to locate the pump housing 40 with respect to the motor housing.

The shaft 26 extends leftward through a central bore 50 in pilot member 44 and outside the motor housing member 20, through a smaller central bore 52 in pump housing 40, and is rotatably mounted in a bearing bore 53 in port member 55. The bore 53 serves as a bearing to support the left end of drive shaft 26. It should be noted that bearing 30 and bearing 53 define the only two bearings for the drive shaft 26, the shaft being unsupported between these hearings. In this regard, it should also be noted that hearing 53 is closely adjacent the left end of the motor housing to reduce the unsupported length of shaft 26.

While the general construction of the pump 11 is described in detail in the Erikson et a1. Patent 2,931,314, noted above, it is believed helpful to describe at least briefly certain operating elements of the pump. Drive shaft 26 is keyed to an inner rotor element 58 of conventional crescent-type gear elements. As shaft 26 rotates carrying gear member 58, an eccentrically mounted outer gear member 60 is driven and fluid is received and expelled through port member 55. The inner gear has an outer diameter smaller than the inner diameter of the outer gear and the space which exists therebetween is closed by a crescent 54. A stationary ring 56 surrounds the outer gear 60 and retains the pumping elements in their proper position. Suitable fasteners 61 extend through a retaining plate 62, stationary ring 56, and port plate and into the pump housing 40, and maintain the gear pump elements 58, and the port plate 55 together as a unit against the pump housing 40. A suitable filter 64 is provided in a reservoir 65 for filtering oil flowing to the pumping elements through port plate 55. High pressure fluid is delivered from the valve plate to a pressureresponsive valve assembly 67 which regulates flow to a suitable port 68 adapted to be connected to the oil burner nozzles. Inlet oil is delivered to the pump through port 69.

A suitable seal assembly 71 is provided within bore 50 for preventing the egress of fluid from within the pump housing to the motor housing. Seal assembly 71 includes a stationary sealing ring 73 in pilot 44 having an axially facing surface engaging an axially facing surface on a sealing ring 75' at an interface 76. Ring 75 is carried on shaft 26 and rotates therewith, by virtue of a driving extension 77 from an annular collar 78 fixed on shaft 26 and providing a seat for a spring 79 which biases seal ring 75 toward ring 73 and urges thrust ring 36 toward the right as viewed in FIG. 1. A grommet 81 on ring 75 prevents leakage along shaft 26, While interface 76 prevents radial leakage.

Accurate alignment is maintained between the left drive shaft bearing 53 and bore 52 in the pump housing 40 by an alignment sleeve 72 fitted within bore 52 and extending within a coaxially formed counterbore 74 in bore 53. It is important that the bearing 28 be accurately aligned with the bearing 53. For the purpose of achieving this end, bore which receives the right-hand bearing member 30 and bore 83 in housing 19 are machined during one setup so that they are accurately aligned. Likewise, bores 46 and 84 in housing member 20 are machined during one setup. Further, seating surface 82 on the pump housing pilot 44 and the pump housing bore 52 are also machined on one setup so that accurate alignment therebetween is achieved. In this manner, housing bore 52 is accurately aligned with respect to hearing member 30. Now, as noted above, the left-hand bearing 53 is coaxially located with respect to located bore 52 by the alignment sleeve 72. Thus, bearing 53 is accurately coaxially aligned with bearing assembly 28.

We claim:

1. An oil burner pump and motor assembly, comprising: amounting flange adapted to be connected to an air duct, a motor housing connected to said mounting flange and extending on the side thereof adapted to be inserted into the air duct, a motor in said housing including a stator and a rotor, a separate pump housing mounted outside of the motor housing on one end thereof and extending on the other side of the mounting flange, rel atively rotatable pumping elements in said pump housing, a unitary drive shaft extending centrally through said rotor and connected to be driven thereby, said drive shaft extending from both ends. of said motor housing, bearing means in the other end of said motor housing for sup-.

porting one end of said shaft, said shaft having a portion extending outwardly beyond said bearing means, a blower fan connected to said outwardly extending portion and surrounding said motor stator and rotor to provide a compact assembly, single bearing means in said pump housing for receiving and supporting the other end of said shaft, both of said bearing means providing the sole support for said shaft, said other end of the shaft being directly connected to drive one of the relatively rotatable pumping elements, and means for accurately locating the pump housing with respect to the motor housing to thereby align each of said bearing means with respect to the other.

2. An oil burner pump and motor assembly as defined in claim 1, wherein said motor housing has first and second coaxial mounting bores therein, one of said bores receiving said housing bearing means, said locating means including a locating pilot on said pump housing received in the other of said motor housing mounting bores.

3. A pump and motor assembly as defined in claim 2, wherein said pump housing has an axially extending bore for receiving said drive draft, said pilot being accurately located concentric with respect to said pump housing bore, whereby said pump housing bore is accurately located with respect to said bores in said motor housing.

4. An oil burner pump and motor assembly as defined in claim 3 and further including a port member fixed within said pump housing, said port member having a bore therein receiving one end of said drive shaft and defining said pump bearing means, and an alignment sleeve in said pump housing bore and extending into and aligning said port member bore with respect to the pump housing bore.

5. An oil burner pump and motor assembly as defined in claim 1, wherein said motor housing includes two generally cup-shaped housing members fixed to either end of said stator whereby the stator is cooled by air passing through the surrounding blower fan, said mounting flange being integral with the housing member adjacent the pump and including a generally radially extending portion from said housing member, an annular generally axially extending portion having mounting ears thereon, said mounting flange being arranged so that a portion of said motor and the entire blower fan project within the air duct and said pump housing projects outside the duct.

6; An oil burner pump and motor assembly as defined in claim 1, wherein said single bearing means in said pump housing directly engages said shaft, one of said pumping elements being supported on said shaft.

References Cited UNITED STATES PATENTS 1,986,003 1/1935 Lum 1036 2,297,049 9/1942 Cotton et a1. 230.1l7 2,450,963 10/1948 Hoover 103-118 2,494,714 1/1950 Lyman 1036 2,931,314 4/1960 Erikson et a1. 103l26 DONLEY J. STOCKING, Primary Examiner. WILBUR J. GOODLIN, Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,360,190 December 26, 1967 Robert W. Erikson et a1.

It is certified that error appears in the above identified patent and that said Letters Patent are hereby corrected as shown below:

In the heading tothe printed specification, line 5, Illinois" should read Delaware Signed and sealed this 10th day of March 1970.

A "SEAL) Attest:

Fletcher, Jr. WILLIAM E. SCHUYLER, IF

Attesting Officer Commissioner of Patents

Claims

1. AN OIL BURNER PUMP AND MOTOR ASSEMBLY, COMPRISING: A MOUNTING FLANGE ADAPTED TO BE CONNECTED TO AN AIR DUCT, A MOTOR HOUSING CONNECTED TO SAID MOUNTING FLANGE AND EXTENDING ON THE SIDE THEREOF ADAPTED TO BE INSERTED INTO THE AIR DUCT, A MOTOR IN SAID HOUSING INCLUDOUTSIDE OF THE MOTOR HOUSING ON ONE END THEREOF AND EXTENDING ON THE OTHER SIDE OF THE MOUNTING FLANGE, RELATIVELY ROTATABLE PUMPING ELEMENTS IN SAID PUMP HOUSING, A UNITARY DRIVE SHAFT EXTENDING CENTRALLY THROUGH HOUSROTOR AND CONNECTED TO BE DRIVEN THEREBY, SAID DRIVE SHAFT EXTENDING FROM BOTH ENDS OF SAID MOTOR HOUSING, BEARING MEANS IN THE OTHER END OF SAID MOTOR HOUSING FRO SUPPORTING ONE END OF SAID SHAFT, SAID SHAFT HAVING A PORTION EXTENDING OUTWARDLY BEYOND SAID BEARING MEANS, A BLOWER FAN CONNECTED TO SAID OUTWARDLY EXTENDING PORTION AND SURROUNDING SAID MOTOR STATOR AND ROTOR TO PROVIDE A COMPACT ASSEMBLY, SINGLE BEARING MEANS IN SAID PUMP HOUSING FOR RECEIVING AND SUPPORTING THE OTHER END OF SAID SHAFT, BOTH OF SAID BEARING MEANS PROVIDING THE SOLE SUPPORT FOR SAID SHAFT, SAID OTHER END OF THE SHAFT BEING DIRECTLY CONNECTED TO DRIVE ONE OF THE RELATIVELY ROTATABLE PUMPING ELEMENTS, AND MEANS FOR ACCURATELY LOCATING THE PUMP HOUSING WITH RESPECT TO THE MOTOR HOUSING TO THEREBY ALIGN EACH OF SAID BEARING MEANS WITH RESPECT TO THE OTHER.