US2665056A - Means for resiliently mounting vanes or frangible pump elements - Google Patents

Description

Jan. 5, 1954 s. G. ORBAN 2,665,056

MEANS FOR RESILIENTLY MOUNTING VANES OR FRANGIBLE PUMP ELEMENTS Filed June 20, 1951 2 Sheets-Sheet 1 INVENTOR.

STEPHEN a. ORB/4N BY my Jan. 5, 1954 Filed June 20, 1951 MEANS FO s. G. ORBAN 2,665,056 R RESILIENTLY MOUNTING VANES FRANGIBLE PUMP ELEMENTS 2 Sheets-Sheet 2 JNVENTOR.

STEPHEN G. ORB/4N Patented Jan. 5, 1954 MEANS FOR RESILIENTLY MOUNTING VANES OR FRANGIBLE PUMP ELE- MENTS Stephen G. Orban, Bloomfield, N. J., assignor to Bendix Aviation Corporation, Teterboro, N. J., a corporation of Delaware Application June 20, 1951, Serial No. 232,512

4 Claims.

This invention relates generally to means for appyling a spring force to a relatively soft, frangible element or body and more particularly has to do with a novel saddle-like button arrangement interposed between a spring and an element made of carbon, graphite or other relatively soft and frangible material whereby the force exerted by the spring may be transmitted to the elemen The instant invention has particular utility when employed to maintain the sliding vane of a dry air rotary pump in operative contact with the rotor thereof.

It has become common practice to utilize sliding vanes made of graphite, or carbon, in dry air rotary pumps, especially where such pumps are designed and constructed to operate at relatively high speed.

Due to the relatively soft and frangible character of the material of such sliding vanes, the

spring loading of the vane so as to maintain it in tinued positive operation of the pump. In other instances, where a resilient pad has been interposed between the end of the spring and the vane, the high temperatures developed during the operation of the pump have resulted in the rapid deterioration or breakdown of the pad. Moreover, the use of a resilient pad has also been found objectionable in that in instances where the bonding agent securing the pad to the vane fractures, the pad, being resilient, does not provide a stable platform between the spring and vane with the result that the vane is apt to shift or move out of alignment with its guides. It is apparent under such conditions the vane may break or wear unevenly, thereby resulting in the breakdown or inefficient operation of the pump. The instant invention has for one of its objects the provision of means for mounting the carbon or graphite vane of a rotary pump so as to overcome the foregoing difficulties.

Among other objects, the present invention contemplates a vane assembly embodying novel means whereby the vane may be operatively positioned relative to the rotor of the pump and in the event the bonding agent securing the vane to the assembly fractures, the vane will be supported in its proper position without any undesirable shifting or moving of the vane relative to the guides thereof.

A further object of the instant invention is to provide a stable mounting platform for a carbon or graphite element whereby a spring force may be transmitted to the element.

The above and other objects and features of the present invention will appear more fully hereinafter from a consideration of the following description taken in connection with the accompanying drawings wherein one embodiment of the invention is illustrated by way of example. It is to be expressly understood, however, that the drawings are for illustration purposes only and are not to be construed as defining th limits of the invention.

In the drawings wherein like reference char acters refer to like parts in the several views:

Fig. 1 is a fragmentary side view, partially in section, of a rotary air pump embodying the novel means for mounting the vane as contemplated by the instant invention;

Fig. 2 is a fragmentary end view showing a vane assembly in elevation and its relationship with the rotor of the pump;

Fig. 3 is an enlarged section through the vane assembly;

Fig. 4 is a plan view of the vane; and

Fig. 5 is an enlarged side view of the saddlelike button.

Referring now to the drawings, Fig. 1 illustrates a rotary dry air pump of a conventional type consisting, in general, of a power unit [0 and an air pumping assembly i l constructed and arranged to be mounted to, and driven by, the power unit Iii.

In this instance, power unit it comprises an electric motor i2 suitably mounted and enclosed within a hollow housing it. An end wall It, closing one end of housing i3, is provided with an extension it in which is mounted an electrical connector or plug IE3 whereby the power unit ill may be connected into a suitable electrical circuit for the operation of motor 12.

The air pumping unit I 1 comprises a casing 3! having head and end walls I8 and i9, respectively, that are adapted to be mounted to opposite sides of casing ll. Head wall I8 is secured to the casing I? by bolts 20 which pass through registered openings in a flange 2| and a flange 22 formed integrally with casing ll and head wall l8, respectively.

In order to mount the pumping assembly H to-the power unit 10, end wall I9 is provided 3 with a lateral extension 23 that extends partially into the open end of housing l3. A snap ring 24 is engaged within an annular recess 25 formed in housing 3 adjacent its open end, and a bearing ring 26, slidable within housing I3, is adapted to engage the inner urface of the snap ring 24'. A series of bolts 21 pass through registered open ings provided in bearing ring 26, end wall l9 and a flange 28 formed on casing I! to the end that the tightening of nuts 29 carried by bolts 21 brings the bearing ring 26 intoengagement with snap ring 24 thereby securely mounting the casing I! to the housing 3.

Head and end walls I8 and I8, respectively, operate with a bore formed in casing-ll to define a cylindrical pump chamber 30. Motor 2 is provided with a shaft 3| that extends through alcentral opening 32 in end wall l9 and across pump chamber 30, where it is journalled in a sealed Suitable bearing 33 mounted in head wall l8. seals 34- are provided to prevent any lubricant utilized in bearing 33iromleaking1into the pump chamber 30.

An eccentric rotor 35 is secured to shaft 31 for rotation therewith and carbon seals 36and 31 tively, with a bore 44 formed in casing-|l 'intermediate the passageways Wand 4|. A slot 45 formed in casing 11 between bore-44- and pump chamber 3|] communicates the former with the latter.

Bore 44 is adapted to receive a'cylindrical insert 46 having angularlydisposed, fl'at'side surfaces and. 48 and a vertic'al'sl'ot 49. "A" vane 50 slidably mounted in slot extends through slot 45 and is adapted at its end 51 to' sealingly contact the rotor 35. Thus,- vane-50' divides slot 45 into passageways 45a and 45b which" communicate with inlet and outlet passageways 40 and 4| respectively.

In order to. apply a resilient pressure to the vane 50 and thereby sealingly. engage the enjdjl thereof with rotor 35, a plurality of spring assemblies, generally indicated by the reference character 53, are mounted in casing I! and are disposed so as to engage, the vane 50 at spaced intervals along the lengththereof. As shown in Fig. 1, the instant pump assembly is provided with two spring assemblies 53, and sinceeach spring assembly 53 is identicalin-structure, only one is described in detail.

. To house the spring assembly 53, casing Hand insert 46 are provided with registered, vertical bores 54 and 55, respectively; A cover plate 56, removably mounted to casing by-a bolt 51-, has fixedly secured thereto a stud or post 58 that is adapted to be snugly received into vertical bore 54. To preventleakage through bore 54, post 58 is provided medially of its length with an annular groove 59 in. which: is mounted a rubber sealing. ring 60. The inner end of post-58 serves as a seat for one end of a. compression spring 6| that is utilized to apply the required resilient load to vane 50.

As above set forth, the engagement of the other endof spring-6| toivane ill-has heretofore presented many'probl'ems Thus; where spring 6| has been placed directly in contact with vane 50, the relative hardness of the materials has resulted in a rapid breakdown of the vane and where a resilient pad has been interposed between the spring BI and vane 50 the high operating-'temperatureand frequent-breaking of the bonding agent has similarly. resulted in inefiicient pump operation.

.The instant invention overcomes the difliculties heretofore experienced by providing a novel saddle-like button 62 that is adapted to be interposed between the spring 6| and vane 50 and which serves to transmit the pressure from the former'to the latter.

As shownin Figures 3 and the saddle-like button 62- comprises a cylindrical body 63 having diametrically opposed, depending flanges 64 which define a transverse channel 65, substantially U shaped in cross-section, at one end of the body 63. The channel 65 is dimensioned so as to receive one endof: the vane:50 :thereimwith the end of the vane 5|) in abutment with the transverse wall of channel 65 and with' the-interior surfaces of flanges 64 snugly embracing the opposite side walls of the vane 50. The body 63 may be centrally recessed as at; 66 andascenrtral aperture 61 extending betweenthe channel 65 and recess 66 is adapted toreceive shank 68 of a rivet orstud69. Rivet 69 is'securedto-body 63 by upsetting the end-of theshank'68thereof,

or by some suitable-bonding 'agent: A- convexa head formed on rivet 69 is thereby: positioned, in channel 65 between the flanges 64, where it engages a concave recess or depression. shown in Fig. 4- and formed in the upper surface" of: the vane 50'; A suitable bonding-agent, such as. sodium silicate, applied to the inner: surfaces of flanges 64 and theconvex head 10 of rivet 69 serves to securely fasten the 'body 63 to the vane 50.

Medially of its length; the'body-63 is provided with an annular peripheral flange 1-3 whichforms a seat for-the lower "end of spring 6|. Thus, spring 6| is operativelypositioned between the lower-end of post 58' and-*the flangela of the saddle-like button 62;

It will be seen'from the-foregoing description that all that is necessary to carry out the teaching of the instant inventionis that the's'addlelike button 62 have a channel for-the reception orv housing'of the upper end of the vane 50;- that therebe provided acooperating' abutmen'tlil and depression "formed in the-channel and vane, and a means 13, for seating the spring-in engagement with the saddle-like; button 62.

Due to'theforegoing arrangement ofparts, when. motor 12, is actuated to rotate the rotor 35, in a clockwise direction as viewed in- Fig; 2, air is drawn intothe pumping'unit 'H throughthe inlet provided-in head'wall I8; From the inlet, the airpasses through-inlet passageway 40' and duct 42,- into bore 44-Wheresurface -41 -deflects the air through passagewayiiai-into the pump chamber 'Airbeing discharged-from pumpchamber 3 6 by-the rotor leaves through. passageway. 451) where itis deflected. by: surface 48: through. duct 43 =into outlet/passageway 4| and from thenceto outlet: 39. Ajonewaytflapper valve 15 operatively: positioned in outlet ,3 9 per-- mits air under pressure of the pump to-pass from the. outlet while; preventing back flow of air into thepumping unit As hereinbefore set forth,- the vane is re-.- siliently urged into contact withrotor 35 It. is apparent, therefore, that as the eccentric rotor.

35 revolves, spring assemblies 53 operate to maintain the end 5| of vane 50 in sealing contact with the rotor 35 to the end that communication between passageways 45a and 45b is prevented.

In the event the bonding agent securing the saddle-like button 62 to vane 59 fractures or fails in any way, the flanges t4 prevent any transverse movement of the saddle-like button 62 relative to the vane 50, while the engagement of the convex head of the rivet 69 with the concave recess H formed in vane 50 prevents any longitudinal movement of vane 50. The saddle-like button 62, therefore, forms a relatively stable platform through which the force exerted by spring 6| is transmitted to the vane 50. Thus, it is apparent that vane 50 continues to reciprocate in slot or guide 49 without shifting or canting relatively thereto and the pump assembly H continues to operate Without loss of efiiciency.

From the foregoing description of the construction and operation of the present invention, it will be apparent that a novel means for maintaining the sliding vane of a rotary type dry air pump in sealing contact with the rotor thereof has been provided in which the several objects of the instant invention have been achieved.

I claim:

1. The combination with a relatively soft frangible element and a spring for applying a force to said element, of a button adapted to be interposed between said element and spring for transmitting force exerted by the spring to the element comprising a body, depending flanges on said body defining a U shaped channel at one end of said body for the reception of said element, said flanges serving to prevent transverse movement of said element in said channel, a convex abutment in said channel, a concave recess in said element for engagement with said convex abutment to prevent longitudinal movement of said element in said channel, and a peripheral flange on said body for engagement with said spring.

2. In a pump having a rotor; the combination comprising a vane slidably contacting said rotor, a plurality of springs for maintaining the vane in contact with the rotor of said pump, a plurality of saddle-like buttons; each of said buttons secured to one end of said vane and engaged by an end of one of said springs, each of said buttons including a cylindrical body, depending flanges on diametrically opposed sides of said body defining a transverse channel at one end of said body to snugly receive one end of said vane, a peripheral flange on the body medially of its length for engagement by said one end of said spring, and a convex abutment mounted in said channel; said vane having a plurality of concave recesses formed in said one end of said vane, and the convex abutment of each button engageable in one of said concave recesses, and bonding means in the channel of each of said buttons securing said vane in said saddle-like buttons.

3. The combination defined by claim 2 in which each of said saddle-like buttons includes a recess formed in its cylindrical body at the opposite end from said flanges, a central aperture extending between the recess and the channel defined by said flanges, a rivet having a shank and a convex head, said rivet being mounted in said body into the shank thereof in said central aperture and the convex head thereof in said channel so as to engage in one of the concave recesses formed in said one end of the vane.

4:. In combination, a rotor, a vane having one end slidably contacting said rotor and a concave recess formed in the opposite end thereof, a saddle-like button comprising a cylindrical body, depending flanges on diametrically opposite sides of said body forming a transverse channel at one end thereof to snugly receive said opposite end of said vane and prevent transverse movement of said vane relative to said body, a convex abutment in said channel and engageable with the concave recess formed in the end of said vane to prevent longitudinal movement of said vane in said channel, a peripheral flange on said body disposed medially of its length, and resilient means engageable with said peripheral flange for maintaining said body in engagement with said vane and said vane in contact with said rotor.

STEPHEN G. ORBAN.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,254,781 Babbitt Sept. 2, 1941 FOREIGN PATENTS Number Country Date 219,650 Great Britain Feb. 12, 1925 346,020 Great Britain Mar. 30, 1931 66 .599 Germany Oct. 18, 1935

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