US3927956A

US3927956A - Fluid actuated motor

Info

Publication number: US3927956A
Application number: US474624A
Authority: US
Inventors: Harley E Linthicum
Original assignee: Carrier Corp
Current assignee: Elliott Turbomachinery Co Inc
Priority date: 1974-05-30
Filing date: 1974-05-30
Publication date: 1975-12-23
Anticipated expiration: 1992-12-23

Abstract

The fluid pressure operating rotary motor of this invention includes end plates mounted in the ends of a tubular cylinder which in turn is mounted in a casing of equal axial length. The peripheries of the end plates are dimensioned for a close fit with the bore of the cylinder. The end plates are formed with bearing receiving recesses which are formed eccentrically with the axis of the cylinder to position the rotor journaled in the bearings in close running fit to one side of the cylinder bore. Each of the end plates is formed with a passage extending radially from the axis of the rotor against the face of the bearing mounted in the recess and outwardly through the periphery of the end plate for the discharge of pressurized fluid into an axially extending passage formed in the side wall of the motor casing. The bore of the motor casing, in which the cylinder is mounted, is formed with an annular groove having communication with the axially extending passage. The groove also communicates with an exhaust port formed in the cylinder, and with an exhaust passage formed in the casing.

Description

United States Patent [191 Linthicum [4 1 Dec. 23, 1975 FLUID ACTUATED MOTOR [75] Inventor: Harley E. Linthicum, Springfield,

Ohio

[73] Assignee: Carrier Corporation, Syracuse, NY.

[22] Filed: May 30, 1974 [21] Appl. No.: 474,624

[52] US. Cl. 418/100; 418/102; 418/270 [51] Int. Cl. F01C 21/04 [58] Field of Search 418/102; 131, 268, 270,

[56] References Cited UNITED STATES PATENTS 6/1911 l-lolt et al 418/270 11/1951 Mitchell. 418/270 2,764,941 10/1956 Miller et al. 418/102 3,272,138 9/1966 Connoy et 418/102 3,429,230 2/1969 Quackenbush 418/270 3,826,597 7/1974 Schmitz 418/270 FOREIGN PATENTS OR APPLICATIONS 423,244 7/1947 ltaly 418/268 92,777 2/1962 Denmark 418/102 Primary Examiner.lohn J. Vrablik Attorney, Agent, or Firm'.l. Raymond Curtin; Donald F. Daley [5 7 ABSTRACT Each of the end plates is formed with a passage extending radially from the axis of the rotor against the face of the -bearing mounted in the recess and outwardly through the periphery of the end plate for the discharge of pressurized fluid into an axially extending passage formed in the side wall of the motor casing. The bore of the motor casing, in which the cylinder is mounted, is formedwith an annular groove having communication with the axially extending passage. The groove also communicates with an exhaust port formed in the cylinder, and with an exhaust passage formed in the casing.

3 Claims, 7 Drawing Figures 1 1 9 v 1 45 77 43 v k US. Patent Dec. 23, 1975 Sheet 2 of2 3,927,956

BJ M7 LII FLUID ACTUATED MOTOR This invention relates, in general, to elastic fluid powered motors and more specifically to the construction and lubrication of pneumatic motors.

BACKGROUND OF THE INVENTION Conventional pneumatic motors are constructed with a rotor mounted eccentrically in a circular bore. Movable vanes mounted radially in the rotor extend outward in contact with the inner surface of the bore and provide sealing for the driving fluid. Inlet and exhaust passages are normally provided in the casing containing the bore to allow the driving fluid to enter, drive the rotor, and exhaust from the motor. The rotor is usually mounted concentrically in a pair of end plates and end caps and the bore is normally constructed eccentrically of the center line of the main body of the motor. One aspect of the present invention eliminates the need for an eccentric bore by providing a motor body with a concentric bore and end caps with bearings mounted eccentrically so that a rotor mounted in the bearings would be in close proximity to one side of the bore.

It is desirable to equalize the pressure on each side of the end plates and on each end of the rotor to eliminate thrust on the rotor and outwardly unbalanced forces on the end plates. It is further desirable to provide lubrication for the rotor bearings without utilizing a separate or external lubricating source.

SUMMARY OF THE INVENTION In view of the foregoing, it is an object of this inven tion to improve pneumatic motors and simplify the manufacture and construction thereof. g It is also an object of this invention to lubricate a pneumatic motor by means of the oil contained in the driving fluid. It is also an object of this invention to balancethe forces acting on the rotors and end plates of a pneumatic motor.

These and other objects of this invention are obtainedby means of a pneumatic motor having a rotor mounted in a pair of end caps and a bore positioned concentrically of the body of the motor. The motor fluid contains lubrication and is channeled from the expansion chamber through openings in the end caps to the rotor bearings, wherein, the motor fluid changes direction and is directed outwardly to the exhaust port. For a better understanding of the invention as well as further objects and features thereof, references are cited in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a lengthwise sectional view of a fluid operated rotary motor embodying my invention, the view being sectioned on line 11, FIG. 2;

FIG. 3 is a view taken on line 3-3, FIG. 1;

FIG. 4 is a bottom plan view of the housing looking upwardly in FIGS. 1, 2 and 6;

FIG. 5 is a side elevational view of the cylinder shell;

FIG. 6 is a sectional view similar to FIG. 2 but taken on a line indicated at line 6-6, FIG. 5; and

FIG. 7 is an enlarged view of the end member and end cap.

DESCRIPTION OF THE PREFERRED EMBODIMENT.

In the preferred embodiment of the invention depicted inthe drawings, the motor consists of an outer casing 10, substantially rectangular in cross section. The side of the casing appearing at the bottom in views 1, 2 and 6 is flat. The casing is formed with a pair of inlet passages 11, 12 and an exhaust passage 13 opening through the bottom wall. As shown in FIGS. 2 and 4, the inlet passages and the exhaust passage are arranged in a straight line in the bottom wall of the casmg..

.The casing isformed with a passage 17 extending from one end of the casing in a direction axially of the casing in the bottom portion thereof. The passage 17 communicates with the exhaust passage 13. The casing is also formed in its upper side wall with a passage 18 extending inwardly from the right end of the casing and terminating short of the opposite end thereof, see FIG. 1. The

passages

17, 18 have communication with a circumferentially extending groove 20 formed in the bore of the casing.

A tubular cylinder shell 23 is positioned in the bore of the casing and has a snug fit therewith and has a length comparable to the length of the casing as shown in the-lower portion of FIG. 1. The cylinder shell 23 is shown separated from the housing in FIG. 5. Referring to FIGS. 5 and 6, the cylinder shell 23 is formed with a pair of circumferentially extending axially spaced apart inlet ports 27 and a similar pair of inlet ports 28. The inlet ports 27 have communication with the inlet passage 11, and the inlet ports 28 have communication with the inletpassage 12. Referring to FIG. 6, when the operating fluid is admitted through the passage 11, the rotor, as will be apparent, will operate in a counterclockwise direction; and when the fluid is admitted through the passage 12 and ports 28, it will be operated in a clockwise direction The cylinder shell 23 is also formed with one or more exhaust ports 30 which have communication with the circumferentially extending groove 20 formed in the bore of the casing. There is a notch 33 formed in each end of the cylinder 23, see FIGS. 1 and 5. Like ends of the

inlet ports

27, 28 are circumferentially spaced apart. to provide an intermediate area 35. Theopposite ends of the

ports

27, 28 are spaced apart, forming an intermediate area 37. As shown in FIG. 6, the intermediate area 35 is somewhat less than while the area 37 extends through an arc of about The outlet port 30 is located diametrically opposite to the intermediate cylinder portion 35. i

A rotor 40 is positioned in the cylinder 23, the diameter of the rotor .being less than the internal diameter of the cylinder shell. The rotor is formed with slots 47 disposed radially in the rotor and being spaced equally circumferentially about the rotor. A vane 48 is positioned in each of the slots 47. There are five of the vanes 48 movable radially in the slots 47 by centrifugal force so that the outer edges of the vanes engage with the bore 25 of the cylinder 23. The rotor 40 is formed at its ends with

trunnions

41, 42 journaled in

bearings

43, 45. The bearings are mounted in bores formed in

end caps

50, 51. The end caps have circular peripheries 52. However, the bearing bores are offset eccentrically from the peripheries of the end caps, see FIGS. 1 and 7. His results in the rotor 40 running in close proximity to the intermediate portion 35 6f the cylinder shell as 3 shown in the views 2 and 6. The end caps 50, 51 are formed with passages 59 in which are mounted dowel or locating pins 54. These pins extend outwardly from the peripheries 52 of the end caps into the notches 33 formed in the ends of the cylinder. These locating pins serve to maintain the end caps properly oriented in the cylinder to effect the close running fit between the rotor and the intermediate portion 35 of the cylinder.

The end caps 50, 51 are formed with annular flanges 70 concentric with the bores in which the

bearings

43, 45 are mounted. The bearing bores in the end caps terminate at annular shoulders 57 and these annular shoulders 57 are formed with radial slots 58 communicating with passages 59. A spacer ring 60 is mounted on each

rotor journal

41, 42. The outer diameter of the spacer ring 60 is less than a bore formed in the inner wall of each end caps so that there isan annular space between the spacer rings and the bore in the end caps. With this arrangement, fluid pressure, leaking inwardly across the ends of the rotor 40, passes through the shoulder slots 58 into the passages 59 and through the passages 61 formed in the locating pins 54. The casing is formed with passages 66 which incline outwardly from the ends of the passage 18 and communicate with the area above the outer ends of the pins 54. Accordingly, the leakage fluid passes 'into the passageway 18 into exhaust connecting groove into the passage 17 and out the exhaust passage 13. With this arrangement with the operating fluid, containing an oil mist, the

bearings

43, 45 are provided lubrication and are cooled by the flow of fluid.

There are provided end plates 75, 76 formed with bosses 77 having bores to receivethe annular portion 70 of the end caps 50, 51. The end plates 75-76 are attached to the ends of the casing 10 by bolts 85 provided with nuts 86 on the ends thereof as shown in FIG. 1.

The important features of the invention are that the end caps 50, 51 are mounted with a snug fit directly in the ends of the cylinder 23 which effects greater precision in the mounting of the rotor in the cylinder 23. The other feature is the passage of operating fluid in contact with the bearings and delivery to the exhaust system of the motor.

Although the present invention has been described in detail by way of illustration and example, it is understoodthat certain changes and modifications inay be made within the scope of the invention.

What is claimed is:

1. In a fluid operated rotary motor of the type wherein a rotor having radially slidable vanes is eccentrically mounted in a cylindrical bore of a casing, end caps having eccentrically located recesses mounted in each end of the cylindrical bore, bearings mounted in the recesses of the end caps and supporting the rotor, end plates mounted on each end pf the casing, fluid supply ports through the casing in communication with the interior of the cylindrical bore and an exhaust port 4 also communicating with the insides of the cylindrical bore, the improvement comprising:

means in said end caps to allow passage of fluid containing lubricant from the cylindrical bore to the bearings; and

means to allow passage of the fluid from the bearings to the exhaust port whereby lubricant in the fluid supply is deposited on the bearings and the pres sure is equalized on both sidesof the end caps. 2. In a fluid operated rotary motor of the type having a casing and a cylindrical bore within the casing, a rotor having radially slidable vanes is eccentrically mounted in the cylindrical bore of the casing, end caps having eccentrically located recesses are mounted in each end of the cylindrical bore, bearings are mounted in the recesses of the end caps rotatably supporting the rotor, end plates are mounted on each end of the casing, fluid supply ports through the casing are in communication with the interior of the cylindrical bore, and an exhaust port also communicates with the inside of the cylindrical bore, the improvement comprising:

first fluid passages through the end caps communicating with the interior of the cylindrical bore and the bearings;

second fluid passages extending from the bearings radially outwardly through the end caps; and

third fluid passages formed in the casing and communicating with the second fluid passages and the exhaust port, to thereby allow passage of fluid in the cylindrical bore to pass through the bearings to the exhaust port.

3. In a fluid operated rotary motor of the type wherein a rotor having radially slidable vanes is eccentrically mounted in a cylindrical bore of a casing, end caps having eccentrically located recesses mounted in each end of the cylindrical bore, bearings mounted in the recesses of the end caps and supporting the rotor, end plates mounted on each end of the casing, fluid supply ports through the casing in communication with the interior of the cylindrical bore, and an exhaust port also communicating with the insides of the cylindrical bore, the improvement comprising:

means in said end caps to allow passage of fluid containing lubricant from the cylindrical bore to the nieans to allow passage of the fluid from the bearings to the exhaust port whereby lubricant in the fluid supply is deposited on the bearings and the pressure is equalized on both sides of the end caps; and said end caps being positioned relative to the cylindrical bore by means of a locating pin and said means to allow passage of the fluid from the bearings to the exhaust port including a drilled hole in said locating pin for the passage of fluid from the bearing to passages in the casing communicating with the exhaust port.

Claims

1. In a fluid operated rotary motor of the type wherein a rotor having radially slidable vanes is eccentrically mounted in a cylindrical bore of a casing, end caps having eccentrically located recesses mounted in each end of the cylindrical bore, bearings mounted in the recesses of the end caps and supporting the rotor, end plates mounted on each end of the casing, fluid supply ports through the casing in communication with the interior of the cylindrical bore and an exhaust port also communicating with the insides of the cylindrical bore, the improvement comprising: means in said end caps to allow passage of fluid containing lubricant from the cylindrical bore to the bearings; and means to allow passage of the fluid from the bearings to the exhaust port whereby lubricant in the fluid supply is deposited on the bearings and the pressure is equalized on both sides of the end caps.

2. In a fluid operated rotary motor of the type having a casing and a cylindrical bore within the casing, a rotor having radially slidable vanes is eccentrically mounted in the cylindrical bore of the casing, end caps having eccentrically located recesses are mounted in each end of the cylindrical bore, bearings are mounted in the recesses of the end caps rotatably supporting the rotor, end plates are moUnted on each end of the casing, fluid supply ports through the casing are in communication with the interior of the cylindrical bore, and an exhaust port also communicates with the inside of the cylindrical bore, the improvement comprising: first fluid passages through the end caps communicating with the interior of the cylindrical bore and the bearings; second fluid passages extending from the bearings radially outwardly through the end caps; and third fluid passages formed in the casing and communicating with the second fluid passages and the exhaust port, to thereby allow passage of fluid in the cylindrical bore to pass through the bearings to the exhaust port.

3. In a fluid operated rotary motor of the type wherein a rotor having radially slidable vanes is eccentrically mounted in a cylindrical bore of a casing, end caps having eccentrically located recesses mounted in each end of the cylindrical bore, bearings mounted in the recesses of the end caps and supporting the rotor, end plates mounted on each end of the casing, fluid supply ports through the casing in communication with the interior of the cylindrical bore, and an exhaust port also communicating with the insides of the cylindrical bore, the improvement comprising: means in said end caps to allow passage of fluid containing lubricant from the cylindrical bore to the bearings; means to allow passage of the fluid from the bearings to the exhaust port whereby lubricant in the fluid supply is deposited on the bearings and the pressure is equalized on both sides of the end caps; and said end caps being positioned relative to the cylindrical bore by means of a locating pin and said means to allow passage of the fluid from the bearings to the exhaust port including a drilled hole in said locating pin for the passage of fluid from the bearing to passages in the casing communicating with the exhaust port.