US1980726A - Compressor - Google Patents

Description

J. F. HIGBEE couPREssoR Nov. 13, '1934.

3 sheets-sheet 1 Filed'u'arcn 27, 1931 ATTORNEYS.

NOV. 13, 1934. J' F' H|GBEE I 1,980,726

COMPRESSOR Filed MaIClLZY, 1931 3 Sheets-Sheet 2 ATTORNEYS.

NOV"- 13, 1934. J. F.7H1GBEE 1,280,726

COMPRESSOR Filed March 27, 1931 3. Sheets-Sheet 3 #1TFT INVENTOR.

ATTORNEYS.

Patented Nov. 13, 1934 UNITED` COMPRESSOR James F. Higbee,'Detroit, Mich., assigner of one- 'half to Stephen A. Griggs, Detroit, Mich.

Application March 27, 1931, Serial No. 525,816 2 Claims. (014239-157) My invention relates to compressors and has particular reference to that type wherein a plurality of blades are rotated rapidly within a cylinder to produce a vacuum.

The object of my invention is to procure a high vacuum without the annoying sound effects which customarily accompanythe pumping operation. As is well known, vacuum pumps and compressors have a, myriad ofuses and in a great number of instances it is extremely desirable to secure a noiseless operation while maintaining a maxi mum efciency. My invention contemplates a pump assembly wherein the lines of joinder between the movable units and the stationary units are constantly sealed by elements under spring pressure. In this way the various units of the assembly are maintained at all times in proper relation to one another and positively urged into such relationship, thereby eliminating the development of much of the noise which customarily is found in such machines.

Another object of my invention is to prolong the life of such a pump and to maintain a constant eiiciency without the necessity of replacing parts. By reason Vof the friction produced between the relatively movable elements there is a tendency for the parts to wear, thereby resulting in inefficient operation and attendant noise. The spring pressed sealing structure which I have incorporated in my pump assembly constantly adjusts itself for the wear which takes place by virtue of such friction and -maintains a tight seal at all times.

Various other objects and meritorious features of my invention will be 'found inthe particular combination and arrangement of parts hereinafter more fully described in conjunction with the drawings wherein:

Fig. 1 is a frontelevation of my improved pump assembly, partly in section,

' Fig. 2 is a sectional plan of the assembly illustrated in Fig. 1,

Fig. 3 is a side elevation, a section being broken away along 3-3 of Fig. 1,

Fig. 4 is a front elevation of one casing unit, Fig. 5 is a perspective of a sealing unit, Fig. 6 is an elevation, partly in section along the line 6"-.6 of'vFig. 7, of my power driven rotor,

Fig. 'l is a section along '7 7 of Fig. 6, Fig. 8 is a perspective of one of the bearing units for the pump blades,

Fig. 9 is a seal for the pump blades, Fig. 10 is a detail of another of the sealing 55 elements,

Fig. '11 is a disassembled View of the pump blades, in elevationand plan, ,Y f

Fig. l2 is a detail of another sealing unit, and

' Fig. 13 is a perspective of the check valve used at the exhaust port. i

The cylinder chamber proper for the pump assembly is composed of an'open ended cylinder 10 which is provided with exterior ns 12 extend.- ing. circumferentially therearound.` On Opposite sides of the cylinder walls are an intake port'14 and an exhaust port 16, each of which is vdivided into a plurality of passageways, as at 18, adja-` cent its opening into the interior of the cylinder. The open ends of the cylinder 10 are closed by the casing units 20 and 22 which are positioned by bolts 23, and each of which is providedv with a pocket 24 and 26 which is designed ,to house a bearing assembly for the power drivenrotor'illus-r trated in Fig. 6; 1" `j The 'rotor includes'a dr'ving shaft 28, an end bearing portionl 30 which is journalled in pocket 26 in a manner to be lmoreclearly dened herein.- after, a cylindrical rotor portion properv32 which is machined out in the manner illustrated at 34 in Fig. 7 for'apurpose to be hereinafter described, and an opposite end bearing portion 36 which is adapted to be journalled inthe pocket 24. Each end face of the rotor proper 321s 'provided` adjacent its periphery at spaced `apa-rt,intervalswith a plurality of pockets 38 extendinginwardly. from segmental grooves 40 which extendfbetween the machined out ,portions 3 4.' y.The 4pockets 38 are adapted to seat. coil vsprings, for a purpose to be more clearly brought out. Y A, v

The bearing 3,0v is providedv .witha bushing 42 which may be shrunk thereaboutandgthecylindrical'inner wallof pocket 26 is provided with a similar bushing 44.,-"1The bushing 42 is flush with the outer extremity oftheibearing 30`whereas the bushing 44 extends the entire length ofthe cylindrical wall of 'pocket' 26.V It `will be noted that this arrangement provides la small:l passage '46 whichis designed for a'vp'urpose which will be more clearly brought out' hereinafter. This passageway also providesa clearance` between'zthe .shouldered portion 30 of l.the-power'driven rotor `and the bottom of pocket 26,..the`reby eliminating `unnecessary `friction. ,iff 1 'f Segmental rings 56 are seated in the grooves 40 and are constantly urged outwardly against the edge faces of bushings 44 and 50 by means of coil springs 58 seated in pockets 38. In this way a tight seal is maintained at each end of the rotor. At the same time any Wear which may take place is taken up or absorbed by the spring elements.

A stud shaft 66 extends through andI is keyed to the'casing4 20 and its axis is concentric with the axis of the cylindrical casing 10. flfhislstud shaft 66 extends into the central opening 68 in the rotor element. The rotor portion proper 32 is of somewhat smaller diameter than the cylindrical casing 10 and is mounted somewhat veccen` trically therein. As may be clearly seenin Fig.L 1, the rotor revolves about the axis A, slightly offset with relation to the coincident axes B of the stud shaft 66 and the cylindrical casing 10.

The portions 34 of the rotor are adapted to@ receive shims 60 (see Fig. 8) which are provided with 'an arcuate 'outer face 62 conforming to the arc of the machined 'out portion and a longitudinal `groove 641extending along the inner flat face. 'Pump'blades 69,'each provided with a plurality of supporting rings '70, are journalled by means of these rings for rotation about stud'shaft 66 'as clearly illustrated in Figs. 1 and 2. Each blade 69 'is adaptedto'extend through a pair of 'shimsf60, there being a spring seal 72 (see Fig. 9) inserted in the groove'64 of each shim to provide a seal 'between the 'blade'and its bearing shims 60. Each of these spring seals comprises a rigid strip 74 having overlapping ends 76 which function to position the 'opposite ends of aspring metal strip 78"as clearly indicated in Fig. 9. i Each vofk the blades 69 is provided with a groove 80 which extendsalong its longitudinal edge and along a portion atleast of itsradial edge as indicated at 82. The bottom of each groove is prolvided with vspring seats 84 adapted'to position coil. springs 85 which bear against a sealing member, 'generally indicated as 8'7, (see-Fig. 12) adaptedto wipe the' cylindrical wall of the casing `1'0 and the vend walls thereof.

The'sealing element '87 illustrated in Fig. 12 inits disassembled position comprises two end pieces 86 `and V88 with depending portions 90 land 92'at their outer extremities and mortised 'portions'at their inner extremities adapted to cooperate Vwith a joining tenent 94'to secure the two rpieces j in adjustable extensible relation.

It will beseen that the'composite sealing unit 87 so made upis adapted to seat in the grooves which are provided along the edges of the pump blades 69 and are inwardly urged` against the wallsr of the pump casing. The' springs 85 operate to 'absorb any wear which may occur and the fact 'that the sealing unit is extensible permits the springs to do this With the end wall seal aswell as the'. cylindrical wall seal;

A pocket 96 is provided in thecylindrical wa'll of the casinglok for receiving a sealingv block 98 (see Fig. 5). This block has a concave arcuate surface100 on one side thereof adapted to` bear 'against'.the' exterior of the rotor portion proper .32for'sealing purposesand a plane surface on A.the opposite side thereof provided with va plurality of spring seats 102. The springs 104 are seated in 102* andbear against the bottom of tion of the blades and thereby maintain a tight seal.. The spring pressed segmental rings 56 maintain a tight seal between the blades and thekend walls of the vpump casing 10, and are assisted in this function by the overhanging portions andl 92 of the seal 87.

Any possible leakage through the bearing 30 of the rotor element escapes through the passageway 46 and into a pocket 106 provided in the end casing 22. A passageway 108 connects thisipocket with passage 110 which opens into the `pump chamberas indicated 'at' 112. The opening in the casing necessitated by drilling .passage 108 is 'closed by plug 114.

The exhaust port 16 is provided with a check valve broadly indicated by the numeral 116 wherein there is a piston 118 having a stem 120 seated by means of'springx122against the exhaust opening. The tension of the 'spring rv122 may be adjustedby the threaded closure member 124 so that the check valve Awill open upon being subjected to any desired pressure created by the pump operation. y

While I have disclosed s'p'ecic'unitsfor securing a complete seal against leakage, it will be rapparent that the broad -idea of 'locating the units as indicatedand providing meanswhereby they are constantly urged into position constitutes the ybasic linventive concept. For that reason I do not intend'to be'limited other than by the appended claims.

I claim:

1. A spring sealof the class described comprising a longitudinal member of rigid construction, said member having "a plane .facel on one side thereof throughout its length andffolded over 'to provide lJ-'shaped extremities for the? member, and a' springinember of somewhat greater length than' the plane faced side ofthe rigid member having Vits ends anchored in said Ushap'ed extremities.

2. In combination with'a pump having a cylindrical "casing, a cylindrical "rotor "eccentrically journalled for rotation therein; pump blades radivally `mounted within the ycasing* for yrotation therein, rocker bearings between 'said` blades and the eccentrically journalled rotor,` alongitudinal -groove in the face of saidV rockerybearings ladja-

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