US2750895A

US2750895A - Rotary pump and motor hydraulic transmission

Info

Publication number: US2750895A
Application number: US189207A
Authority: US
Inventors: Sturm Erwin
Original assignee: Individual
Current assignee: Individual
Priority date: 1949-10-14
Filing date: 1950-10-09
Publication date: 1956-06-19
Anticipated expiration: 1973-06-19

Description

June 19, 1956 s uR 2,750,895

ROTARY PUMP AND MOTOR HYDRAULIC TRANSMISSION Filed Oct. 9, 1950 2 Sheets-Sheet 1 Jiwezaiar:

June 19, 1956 E. STURM 2,750,895

ROTARY PUMP AND MOTOR HYDRAULIC TRANSMISSION Filed Oct. 9, 1950 2 Sheets-Sheet 2 H O 66 a J H 2 :l l 61 B, 31

.Z 39a 0 o 1-? J K1 9 1 r United States RUTARY PUMP AND IVIOTOR HYDRAULIC TRANSMISSION This invention relates to rotary machines, and more particularly to rotary machines having at least one vane drum with a plurality of vanes mounted therein, and having a casing enclosing the same.

Preferably rotary machines of this kind are used for hydraulic drives wherein two rotary machines are hydraulically coupled with each other. one of said hydraulic machines being employed as a pump, the other being employed as a motor. In hitherto known hydraulic drives of this type each casing enclosing a vane drum and the vanes mounted therein is carried my means of two ball hearings or roller bearings in a support, which, in turn may be adjusted eccentrically to the main axis of the drive. Unavoidable inaccuracies in the construction of the bearings cause non-uniform strains and friction losses in such known hydraulic drives. Efforts have been made to overcome such disadvantages by the use of additional means or by a preliminary setting of the drive on a testing stand. These efforts, however, proved to be unsatisfactory, as in the first instance, the manufacturing costs are increased, and in the second instance, the disadvantages may re-occur at intervals during the operation of the drive.

An object of the present invention is to overcome above mentioned disadvantages of hydraulic drives in a satisfactory manner.

Another object of the present invention is to improve on the art of rotary machines as now ordinarily made.

Other objects and structural details of the invention will be apparent from the following description when read in conjunction with the accompanying drawings forming part of this specification, wherein:

Fig. 1 is a vertical sectional view of a hydraulic drive according to the invention, taken on line II of Fig. 2;

Fig. 2 is a sectional view of the hydraulic device, taken on line lI-II of Fig. 1;

Fig. 3 is a sectional view of the hydraulic drive taken .on line lII-III of Fig. 1;

Fig. 4 is a top plan view, partly in section along line 'lVIV of Fig. 2, of the support of the casing enclosing V ,the vane drums, and

. bolts 3. As best shown in Fig. 3, the line of separation between said two

portions

1 and 2 of the housing is in the same horizontalplane as the main longitudinal axis of the drive. As best shown in Fig. l, the hydraulic drive has two equal component parts, one ofwhich is employed as a pump, the other as a motor. These component parts are connected with each other in a manner known per so by conduits extending through the guide shaft 4. Each component part includes a vane drum, the hub 5 of which encircles the associated end or bearing portion of the guide shaft 4; each vane drum is rotatably ICC mounted in the

housing

1, 2 by means of ball bearings 6. The inner ball bearings 6 are engaged with semicircular lugs 1' and 2' arranged on the lower and

upper portions

1 and 2 respectively of the housing. The inputor output-stud 7 is connected with the hub 5 by a pin or the like in a manner known per se. The wheel-like portion 8 of the vane drum receives the vanes 9 in a manner known per se. According to the embodiment shown in the drawings, the vane drum of each component part is provided with seven vanes 9. A casing comprising two front covers 10 and a jacket 11 rigidly connected with each other by bolts 12 enclose the vane drum and the vanes arranged therein. A ball bearing 13 or 14, respectively, is arranged between each front cover 10 of the casing and a support 15. The inner races of said

ball bearings

13 and 14 snugly fit on the hubs of the casing 141, 11, while the outer races of said ball bearings snugly fit into the recesses of the suport 15. According to the invention, said support 15 is provided with two journals 16 and 17 (see Fig. 2) inserted into apertures of the housing closed by

covers

18 and 19. Furthermore, as best shown in Fig. 1, the outer surfaces of the covers 10, beyond their contact with the inner races of the

ball bearings

13, 14, are of conical shape, while the inner surfaces of the support 15 are in a plane perpendicular to the longitudinal axis of the vane drum, whereby spaces increasing in width towards the circumference of the

easing

10, 11 are formed between the covers 10 and the inner walls of the support 15. Therefore, the support 15 being rockably mounted in the

housing

1, 2 by the journals 16, 17 (Fig. 2) may perform oscillations in the direction of the double arrow X (see Fig. 1) about an axis of rotation determined by the line of intersection between the horizontal center plane located in the axis of the vane and a vertical center plane located centrally with reference to the ends of the vane drum.

The support 15 is in the shape of a box surrounding the

casing

10, 11, the lateral inner surfaces of said boxlike supports 15 being in planes perpendicular to the axis of rotation of the vane drum and forming in conjunction with the lateral surfaces of the

casing

10, 11, facing same, the above mentioned space 10a increasing in width towards the circumference of the casing.

According to the embodiment shown in Figs. 1 to 4, said support 15 of the

casing

10, 11 comprises two

symmetrical halves

20 and 21 connected with each other by set pins 22 and bolts 23. The

cylindrical journals

16 and 17 are integral with the associated support 15 of the

casing

10, 11.

Fig. 5 illustrates a different embodiment of a support of the

casing

10, 11, seen in the direction of the axis of rotation of said support; the left hand portion of Fig. 5 is a side elevational view and the right hand portion of Fig. 5 is a vertical central sectional view of said support. Again, the support 150 is in the shape of a box 20a, one side wall of said box 20a, however, being formed by a detachable ring 21a. The support 150 may be swingably mounted in the

housing

1, 2 by means of

journals

16 and 17 arranged at diametrically opposite portions of said box.

In order to adjust the support 15 of the

casing

10, 11 eccentrically to the main axis of the drive, the threaded end of a spindle 25 rotatably arranged in a bore of the cover 19 and provided with a setting handle 24 is engaged with a threaded bore of said support 15. Thus,

the support 15 may be displaced by a rotation of the handle 24 along an axis of adjustment identical with above described axis of rotation of said support.

A more detailed description of the construction and arrangement of the guide shaft in the machine can be i c find at the end of this description.

According to the embodimeht shown in Fig. 5, the support 1549 capable of carrying the casing enclosing the vane drum of the hydraulic drive is in the shape of a shell 20a having a removable annular cover 21a inserted therein. v

Qvving to above described oscillatable mounting of the support or 150 in the housing of the machine inaccuracies in the constriic'tion of the

ball bearings

13 and 14, or differences of pressure between the .

ball bearings

13 and 14 area'utomatically compensated for bya corresponding inclination of the

support

15 or 150. Thus a uniform bearing action of the

ball bearings

13 and 14 is obtained whereby friction losses are reduced to a minimum and a special oil cooling arrangement may be dispensed w ith. p t

Moreover, as the axisfof the oscillating journals is in the sam horizontal plane as the line of separation between thelower anduppe'rpor'tions land 2 of the housing of the machine, the assembly comprising the rotary parts of the machine i together with the guide shaft inserted into the cente'r bores 'of the vase drums may be readily mounted on the lower portion l'of the housing.

urthermore, the two' s'ectional construction of the support of the casing enclosing the vane drum contributes to anextremely high resistance of said support to bending strain. According to the embodiment shown in Figs. l to 4, thefline'of separation between the two sections and 21'of'the support 15 is in a plane of symmetry including the longitudinal a'xis of the oscillating journals l6 and i7, and being perpendicular to the axis of rotationof the vanadium ofthe machine. According to the ernbodiment shown in Fig. 5, the'two sections of the'support 15% comprise the'shell 20a and the annular cover zla. V

The guide shaft 4 consists of a center piece 26 and bearing portions 27 and 2'8,respectively, into which the centerpiece continues axially at each of its sides, said center piece 26 is'integral with 'said bearing portions 27 and 28. A connecting piece 29 carried by the center piece 26 passes through'an aperture of the portion '2 of the

housing

1,2 of the drive, whereby the "guide shaft 4 is preventedifro'm rotation. Chekivalves 29a projecting into the oil chamber 'are arrang ed at the lower side of the center piece 26;one of said check valves 2% is associated with the suction conduit, the'other one is associated with 'the'pressure conduit. Ina similar manner two safety valves Zib'a'r e arranged at the upperside'of said center piece 26, "o'nefof said safety valves'29 b being associated with t'hefsuction conduit', the other one being 'ass'ociatedfwith thejpressur'e conduit.

I As best shown in Fig.3, 'there'is'a clearance"fltibetween the ring portions rg'z'er the'h ousing 1,2 andthe' center pieces 26, and connecting pieces 29, so that thecen'ter pieces and, consequently, 'the'entire guide shaft may be radially displacedi'soinewhatin the housing. 'The bearing portions 27 ahd' ZS, however, snugly fit into the bores of the vane drums without play. Therefore, the guide shaft may follow the radial movements 'of the vane drums caused by the bearing play of'theball' bearings 6. Such construction permits a reduction of the hitherto customary tolerances between the guide 'shaft and the holes of the hubs of the vane drums by the amount of the entire bearing play of the ball b'earingsof the vane drums.

The connecting pieces 2 communicate with the suctionand pres'su re-conduits 32'through'bores 31 extending transversely through the center piece 26 of the guide shaft 4, A

'In order to obtain a pressure relieffthebearing portions 27, 28 of the guide shaft 4 areprovided with'arcuate shallow recesses "33 corresponding,'with-respect' to area, to the openings of the suction'-' and pressure-conduits 32. As best shown in Fig. 6,'each of 'the recesses 33 is connectedwith the opposite con'duit 32 by means of a bore 35, so that the pressure"in the opposite conduit'is led to the associatedrede'ss. Thisariangement Of'surll faces of pressure relief is a contributing factor to a reduction of the friction between the guide shaft and the vane drums to a minimum.

Preferably, oil is used as driving medium for the hydraulic drive described above. The operation of hydraulic drives of this kind is known, so that a detailed desorption thereof is unnecessary.

The construction according to the invention may also be applied to drives equipped with pumps with rotating pistons.

I have described a preferred embodiment of my invention, but it is understood that this disclosure is for the purpose of illustration and that various omissions or changes in shape, proportion 'and arrangement of parts, as well as the substitution of equivalent elements for those herein shown and described, may be made without departing in any way from the spirit and scope of the invention as set forth in the appended claims.

What I claim is:

1. In arotary machine, the-combination of: a housing, a vane drum including a series of vanes, said vane drum being rotatably mounted in said housing, a casing enclosing said vane drum with-said vanes, a support, journals arranged on said support at opposite sides thereof, said journals being axially displaceably and oscillatably mounted in said housing, a p'air of bearings'on said support, said 'c'a'sing being rotatably mounted in 'said bearings of said support, said support'being displaceable-along an axis of adjustmentdetermined'by the line 'of intersectionbetween the horizontal plane-located in the axis of said vane drum and a vertical center plane located centrally with reference to the ends of said vane drum, and'adjusting means associated with said support for displacingsame "along said axis 'of adjustment for an adjust ment of the eccentric position of 'saidsupp'ort relative to said vane drum, said support being rockable about said axis of adjustment realtive to said casing for an automatic'compensatio'n'for differences of pressure in said b'earin'gs'during'an operation of the'machine, said support comprising two sections detachably connected with each other, the line of separation of said two sections being in a plane of symmetry including the longitudinal axis of said journals and being perpendicular to the'axis of rotation of said vane'd'rum.

2.In'a rotary machine,"the combination of: ahousing, a vane drum including a series of vanes, said vane drum "beingrotatably mounted in said housing, a casing "enclosing'said vane drum with'said vanes, a support,

being axially displaceably mounted in said housing, a

pair of bearings on' said support, said casing being rotatably mountedm said bearings of said support, said support being displaceable along an "axis of adjustment determined by theline of intersection between the-horizontal plane located in the axis of said vane drum and a vertical center plane located centrally with reference to the ends of said vane drum, and adjusting means associated with said support for displacingsame along said axis'of adjustment for-an adjustmentof the eccentric position of said support relative to said-vane drum, said support being rockable about said axis of adjustment releative to said'casingfor an automatic compensation fordiiferences of pressure in said bearings during an operation of the machine, said support comprising two sections detachably connected with each other, the line of separation of said two-sectionsbeing in aplane of symmetry includingthe longitudinabaxisof said journals and being perpendicular tothe axis of rotation of said vane drum.

" ing enclosing said-vane drum with said vanes, asupp'ort;journalsarranged on said-support at opposite sides thereof, said journals being axially displaceably and oscillatably mounted in said housing, a pair of bearings on said support, said casing being rotatably mounted in said bearings of said support, said support being displaceable along an axis of adjustment determined by the line of intersection between the horizontal plane located in the axis of said vane drum and a vertical center plane located centrally with reference to the ends of said vane drum, and adjusting means associated with said support for displacing same along said axis of adjustment for an adjustment of the eccentric position of said support relative to said vane drum, said support being rockable about said axis of adjustment relative to said casing for an automatic compensation for diiferences of pressure in said bearings during an operation of the machine, saidsupport comprising a shell-like body and a covering element detachably mounted on the latter.

4. In a rotary machine, the combination of: a housing, a vane drum including a series of vanes, said vane drum being rotatably mounted in said housing, a casing enclosing said vane drum with said vanes, a support, journals arranged on said support at opposite sides thereof, said journals being axially displaceably and oscillatably mounted in said housing, a pair of bearings on said support, said casing being rotatably mounted in said bearings of said support, said support being displaceable along an axis of adjustment determined by the line of intersection between the horizontal plane located in the axis of said vane drum and a vertical center plane located centrally with reference to the ends of said vane drum, and adjusting means associated with said support for displacing same along said axis of adjustment for an adjustment of the eccentric position of said support relative to said vane drum, said support being rockable about said axis of adjustment relative to said casing for an automatic compensation for differences of pressure in said bearings during an operation of the machine, said support comprising a shell-like body and an annular cover detachably mounted on the latter.

5. In a rotary machine, the combination of: a housing, a vane drum including a series of vanes, said vane drum being rotatably mounted in said housing, a casing enclosing said vane drum with said vanes, a support movably mounted in said housing, said support being in the shape of a hollow body enclosing said casing, a pair of ball bearings engaged with said support and said casing for a rotatable arrangement of said casing in said support, said casing and said support having respectively, side walls facing each other, said side walls diverging from said ball bearings towards the circumference of said casing so as to form spaces, said support being displaceable along an axis of adjustment determined by the line of intersection between the horizontal plane located in the axis of said vane drum and a vertical center plane located centrally with reference to the ends of said vane drum, and adjusting means associated with said support for displacing same along said axis of adjustment for an adjustment of the eccentric position of said support relative to said vane drum, said support being rockable about said axis of adjustment relative to said casing for an automatic compensation for differences of pressure in said bearings during an operation of the machine, said ;support comprising two sections detachably connected with each other.

6. In a rotary machine, the combination of: a housjing, a vane drum including a series of vanes, said vane drum being rotatably mounted in said housing, a casing enclosing said vane drum with said vanes, a support mov- .'ably mounted in said housing, said support being in the shape of a hollow body enclosing said casing, a pair of ball bearings engaged with said support and said casing for a rotatable arrangement of said casing in said support, said casing and said support having respectively, side walls facing each other, said side walls diverging from said ball bearings towards the circumference of said casing so as to form spaces, said support being displaceable along an axis of adjustment determined by the line of intersection between the horizontal plane located in the axis of said vane drum and a vertical center plane located centrally with reference to the ends of said vane drum, and adjusting means associated with said support for displacing same along said axis of adjustment for an adjustment of the eccentric position of said support relative tosaid vane drum, said support being rockable about said axis of adjustment relative to said casing for an automatic compensation for differences of pressure in said bearings during an operation of the machine, said support comprising two sections detachably connected with each other, journals rotatably mounted in said housing being arranged on said support, and the line of separation of said two sections being in a plane of symmetry including the longitudinal axis of said journals and being perpendicular to the axis of rotation of said vane drum.

7. In a rotary machine, the combination of: a housing, a vane drum including a series of vanes, said vane drum being rotatably mounted in said housing, a casing enclosing said vane drum with said vanes, a support, a pair of ball bearings on said support, said casing being rotatably mounted in said ball bearings of said support,

journals arranged coaxially on said support so as to have a common axis, said journals supporting said support displaceably in said housing, the common axis of said journals being arranged perpendicularly to the axis of rotation of said vane drum, and adjusting means cooperating with said support for adjusting the eccentric po sition of said casing with respect to said vane drum, said casing and said support defining an axial clearance having a width allowing a lateral rocking of said support from the direction of displacement of said support enabling the compensation of the tolerances required for the manufacture of said ball bearings and the seats thereof, and a uniform loading of both said ball bearings.

8. In a rotary machine as claimed in claim 7, said casing having conically shaped side walls defining said axial clearance with said support.

9. In a rotary machine as claimed in claim 8, said. support having side walls arranged in planes substantially perpendicular to the longitudinal axis of said vane: drum and defining said axial clearance with said conically shaped side walls of said casing.

10. In a rotary machine as claimed in claim 7, said. support being designed as a hollow body including two sections detachably connected with each other, the line: of separation of said two sections being in a plane per-- pendicular to the axis of rotation of said vane drum,. one of said two sections forming one piece with one off said journals.

11. In a rotary machine, the combination of: a cen tral axial body having inlet and outlet conduits, a housing enclosing said axial body, suction and pressure con-- duits connected to said inlet and outlet conduits, a vanedrum arranged in said housing for rotation about said; axial body, said vane drum including a series of radial. slots and radial channels, a series of vanes arranged in said radial slots of said vane drum so as to be displace-- able with respect to the latter, a casing enclosing said vane drum with said vanes, said casing rotating freely and being displaceable with respect to said vane drum, said casing forming with said vane drum a variable cresent-shaped working chamber subdivided by said vanes into parts connected by said conduits in said axial body to said suction and pressure conduits, a support designed as a hollow body enclosing said casing, journals connected to said support and arranged perpendicularly to the axis of rotation of said vane drum, said journalssupporting said support displaceably in said housing, a pair of ball bearings arranged between said support and said casing, a pair of outer races forming part of said ball. bearings, respectively, first side walls forming part of said support and adjoining said outer races towards the perimeter'of said support; and second side walls forming part of said casing and being separated from said first side walls by a clearance having a width enabling, during operation of the machine, thecompensation of the tolerances required for the manufacture ofsaid' ball bearings and the seats thereof, and a uniform loading of both said ball'bearings.

1-2; Ina rotary machine as claimed in claim 11, said support including; two equal sectionsv detachably connected'with each other, the line of separation of said tWo sections being in a plane of" symmetry including the longitudinal axis of said journals and being perpendicular to the axis of rotation of said vane drum, each of said sections forming one piece with the associated one of said journals.

References Cited in the file, of this patent UNITED STATES PATENTS 1,965,388;- Ott'- July 3;

5 2,049,092 Sturmi July. 28; 2,309,148 Wilsomet: all Jan. 26, 2,348,428- Tucker: May 9, 2,420,155 Tucker May 6, 2,469,097 Wremr May 3,

10 2,656,860 Lester Aug. 28,

FOREIGN PATENTS 596,902 Great Britain Jan. 13,

OTHER REFERENCES May