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Publication numberUS2826179 A
Publication typeGrant
Publication dateMar 11, 1958
Filing dateAug 2, 1954
Priority dateAug 2, 1954
Publication numberUS 2826179 A, US 2826179A, US-A-2826179, US2826179 A, US2826179A
InventorsGraham Mackellar K, Klessig Ernst F, Raupp Ray J
Original AssigneeAirway Products Inc
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Hydraulic motor
US 2826179 A
Abstract  available in
Images(3)
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Claims  available in
Description  (OCR text may contain errors)

March 11, 1958 E. F. KLEKSSIG ETAL 2,826,179

HYDRAULIC MOTOR 5 Sheets-Sheet 1 I Filed Aug. 2, 1954 A, v 4 INVENTORS v I4 ERNST EKLESSIG 37 MocKELLAR K.GRAHAM KAY J- RAUPP FIG.5. VIWQRZNELYES} March 11,1958 E. F. KLESSIG m 2,826,119

HYDRAULIC MOTOR 3 Sheets-Slieet 3 Filed Aug. 2, 1954 FIG.6.

Fl GB. 5e

INVENTORS ERNST F. KLESSIG YMOCKELLAR K.GRAHAM RAY J. RAUPP WW,W

ATTORNEYS United States Patent HYDRAULIC MOTOR Ernst F. Klessig, Berkley, MacKellar K. Graham, Detroit, and Ray J. Raupp, Birmingham, Mich., assignors to Airway Products, Inc., Pontiac, Mich., a corporation of Michigan Application August 2, 1954, Serial No. 447,252

9 Claims. (Cl. 121-87) This invention relates to hydraulic motors and more particularly to vane type hydraulic motors. The expression vane type hydraulic motor as employed herein is intended to include not only motors having rotors provided with the ordinary flat vanes but also those having any other type of suitable driving elements such as cylindrical rollers, for example.

One object of this invention is to provide a vane type hydraulic motor having driving elements mounted on the rotor for in and out movement as determined by a guide track in which provision is made for maintaining the driving elements in continuous contact with the guide track independently of centrifugal force.

Another object of this invention is to provide a reversible vane type hydraulic motor having provision for maintaining the driving elements in continuous contact with the guide track independently of centrifugal force and irrespective of the direction of rotor rotation.

Still another object of this invention is to provide a hydraulic motor having means for subjecting the inner ends of the driving elements to a pressure greater than the pressure to which the outer ends of the driving elements are subjected as they pass through the working or fluid pressure space. Accordingly, the driving elements will be urged outwardly for continuous contact with the guide track.

A further object of this invention is to provide a hydraulic motor having means for maintaining the driving elements in continuous contact with the guide track, said means being effective to accomplish this purpose through a wide range of rotor speeds.

Other objects of the invention will become apparent as the following description proceeds, especially when taken in conjunction with the accompanying drawings wherein:

Figure 1 is a longitudinal sectional view of a hydraulic motor constructed in accordance with the present invention;

Figure 2 is a semi-diagrammatic exploded view of the motor showing to advantage the path of the operating fluid, the motor proper being shown in elevation with the various ports of the timing plates being indicated thereon in dotted lines in their true positions relative to the motor proper, and the cover and body member which contain the valves being shown in cross section;

Figure 3 is an elevational view of the rear side of the front timing plate;

Figure 4 is an elevational view of the front side of the front timing plate;

Figure 5 is a sectional view taken along the line 55 on Figure 3;

Figure 6 is an elevational view of the front side of the rear'timing plate;

Figure 7 is an elevational view of the rear side of the rear timing plate; and

Figure 8 is a sectional view taken along the line 8-8 onFigure 6.

Referring now more particularly to the drawings, the

motoflassembly is generally indicated by the reference character 10 and includes a motor proper 12, front and rear timing plates 14 and 16 on opposite sides of the motor proper, a body member 13 and a cover 2h. Four bolts 21 extend through aligned apertures 22 in the motor proper, timing plates, body member and cover to hold the assembly together, and a pin 23 extends through apertures 24 in the motor proper and timing plates to properly align them. Suitable sealing rings 24' are provided between the various parts. The motor proper 12 comprises a stator 25 having a chamber 26 in which is supported a rotor 27. The rotor is in the form of a circular disc and the stator cavity or chamber is of generally oval shape having a minor diameter substantially equal to the diameter of the rotor and having a major diameter somewhat greater than its minor diameter to provide the arcuate working or fluid pressure spaces 28 and 29 at diametrically opposite points in the chamber.

The rotor is formed with a plurality of circumferentially spaced recesses 3i about its periphery, and driving elements 31, in this instance in the form of cylindrical rollers extending axially of the rotor, are respectively supported in the recesses for rotation and for in and out sliding movement substantially radially of the rotor. The annular wall in the stator which defines the chamber 26 provides a track 32 for guiding the in and out movement of the driving rollers 31.

The motor proper 12 is sandwiched between the front and rear timing plates 14- and 116 and the sides or axial ends of the chamber 26 of the motor proper are defined by the adjacent surfaces of the timing plates. The timing plates are provided with suitable ports for admitting fluid under pressure to and exhausting the same from the fluid pressure spaces 28 and 29 to drive the rotor in opposite directions. The timing plates are also provided with suitable ports for supplying fluid under pressure to the inner ends of the recesses 30 to urge the driving elements outwardly in continuous contact with the track 32 when the outer ends of the driving elements pass through the fluid pressure spaces 28 and 29. Figure 2 illustrates semi-diagrammatically these ports in their true relationship to the motor proper, and also the path of fluid to these ports from the cover and the body member.

In detail, the front timing plate 14 is provided with a pair of axially extending through passages 33 and 34 which terminate at the rear ends in ports 35 and 36 disposed to register with the fluid pressure spaces 28 and 29 respectively at points adjacent one end thereof.

These ports serve as a means for either supplying fluid under pressure to the fluid pressure spaces to drive the rotor in one direction or for exhausting the fluid under pressure from the spaces as the driving elements approach said ports when the rotor is driven in the o posite direction. Passages 33 and 34 communicate with an annular groove 37 in the front face of the timing plate 14, and groove 37 registers with an annular groove 33 in the rear face of body member 18.

Fluid under pressure is supplied to the inner ends of the rotor recesses 30 during the time that the outer ends of the driving elements pass through the region of the ports 35 and 36 by the ports 39 and 49. Ports 39 and 4t) communicate with an annular groove 41 on the front side of timing plate 14 by passages 42 and 43, and the annular groove 41 registers with an annular groove 44 in the rear face of body member 18.

The rear timing plate 16 is similar in construction to the front timing plate although having a somewhat different porting arrangement. The rear timing plate is provided with a pair of axially extending passages 50 and 51 which terminate at the front ends in ports 52 and 53 disposed to register with the fluid pressure spaces 28 and 29 at points adjacent the ends thereof opposite the ends served by ports 35 and 36 of the front timing plate.

Ports 52 and 53 serve either to supply fluid under pressure to the fluid pressure spaces to drive the rotor in one direction, or to exhaust the fluid pressure spaces when the rotor is driven in the opposite direction. Passages 51 and 52 communicate with an annular groove 54 in the rear face of the rear timing plate, groove 54 registering with an annular groove 55 in the front face of the cover 20.

The front face of the rear timing plate is also formed with ports 56 and 57 which communicate with the inner ends of the recesses during the time that the driving rollers therein pass through the region of the ports 52 and 53-, and serve to urge the rollers into continuous contact with the guide track. Ports 56 and 57 communicate with an annular groove 58 in the rear face of the rear timing plate by passages 59 and 60, and the annular groove 58 registers with an annular groove 61 in the front face of the cover.

The body member is provided with suitable passages for the passage of fluid to and from the ports of the front timing plate. Thus, it will be seen that the body member has a main passage 65 having a port 66 at one end for connection to a reversible fluid pump 67. The opposite end of the main passage 65 communicates with a valve passage 67 which is closed at the outer end by a suitable plug 68. Extending from the valve passage 67 is a return passage 69 communicating with the main passage 65 adjacent to the connecting port 66.

Supported within the valve passage 67 are three check valves 70, '71 and 72 of identical construction. The check valves comprise hollow valve bodies 73 arranged in end to end relation and retained between the reduced portion 74 of valve passage 67 and the retainer plug 68. The check valves have valve elements 75 provided with sleeve extensions 76 which are slidably guided within the hollow valve bodies, and coil springs 78 compressed between a shoulder portion 79 of the sleeve and the valve body of the adjacent check valve normally urge the valve elements against the respective seats 80 of the valve bodies. A passage 31 connects groove 38 of the body member 13 with the valve passage 67 in the region between the valve elements of check valves 71 and 72.

A passage 82 connects the annular groove 44 of body member 18 with the valve passage 67 in the region between the valve elements of check valves 70 and 71. Suitable apertures 83 and 84 are provided in the valve bodies and sleeve extensions of the valve elements to permit the free passage of fluid.

The cover 20 is provided with a system of passages which are substantially the same as those in the body member 18. Thus it will be seen that the cover has a main passage with a port 91 at one end for connection to the fluid pump 67'. The opposite end of the main passage 96 communicates with a valve passage 92 which is closed at the outer end by a suitable plug 93 threaded into the cover. Extending from the valve passage 92 is a return passage 94 communicating with the main passage 99 at a point adjacent to the connecting port 91.

Supported within the valve passage 92 are three check valves 95, 96 and 97 which are of identical construction and exactly the same as the identical check valves 70, 71 and '72 in the body member. The check valves 95, 96 and 97 are arranged in end to end relation and retained between the reduced portion 98 of valve passage 92 and the retainer plug 93. A passage 99 connects groove" 55 in the front face of the cover with the valve passage 92 in the region between the valve elements of check valves 96 and 97. A passage 100 connects the annular groove 61 in the front face of the cover with valve passage 92. in the region between the valve elements of check valves 95 and 96.

While the valves 70-72 and 95-97 are check valves and permit flow therethrough in one direction only, they are also pressure reducing valves because of their. pressure reducing effect upon fluid passing therethrough It will be noted that the rear timing plate 16 is formed with recesses 102 and 103 in the front face thereof which respectively register with the ports 35 and 36, and recesses 104 and 105 which respectively register with the ports 39 and 41) of the front timing plate. It will also be noted that the front timing plate is provided in its rear face with recesses 106 and 107 which respectively register with the ports 52 and 53 in the rear timing plate, and recesses 108 and 109 which respectively register with the ports 56 and 57 of the rear timing plate. The foregoing arrangement is such that forces exerted upon the rotor by fluid pressure in an axial direction through the ports are completely balanced.

The rotor 27 is formed with a central aperture for receiving the rear end of the drive shaft 116, the

drive shaft extending forwardly through apertures in the front timing plate 14 and the body member 18. The central aperture 115 in the rotor is formed with splines .117 engageable with similar splines on the rear endof the drive shaft to provide a drive connection. The shaft 116 is supported for rotation by a ball bearing assembly 118 supported in a recess at the front end of the body member and also by a bearing 119 supported in the central aperture of the timing plate 14-. A suitable fluid sealgenerally indicated at 120 is carried by the body member at the front side of the ball bearing 118 and is held in place by a suitable snap ring 121 removably secured in an annular groove of the recess at the front end of the body member. The front end of the drive shaft 116 may be connected to any appliance which it is desired to drive by this motor.

The operation of the motor will now be described. Assuming that it is desired to drive the motor in a counterclockwise direction as viewed in Figure 2, the connecting port 66 of the body member will be connected to the output of the pump as illustrated, and the pump output will enter the main passage-65. The pressure of the fluid thus entering the body member will be sufficient to unseat the valve element of check valve 70, thereby enabling the fluid to pass from the body member through passage 82 into annular groove 41 of the front timing plate from whence it is distributed to the inner ends of the recesses 33 of the rotor through ports 39 and 46. There will, of course, be a drop in thepressur of the fluid as it passes check valve '76;

A portion of the fluid passing check valve 70' will unseat the valve element of check valve 71 enabling that portion of the fluid to pass from the body member through passage 81 into the annular groove 37 of the front timing plate from whence it is distributed to the fluid pressure spaces 28 and 29 in the motor proper through ports 35 and 36 to drive the rotor in. a counterclockwise direction. The pressure of the fluid supplied to the fluid pressure spaces through ports 35 and 36' will be somewhat less than that supplied to the inner ends of the recesses through ports 39' and 46 due to the fact that the portion of the fluid supplied to the ports 35 and 36 must pass the check valve 71 and therefore undergo a reduction in pressure. The check valves are so constructed that the greater pressure supplied to the inner ends of the recesses will be sufficient to maintain the driving rollers in contact with the guide track of the motor chamber 26. After the driving rollers have passed from the region of the ports 39 and 40, the fluid trapped in the recesses beneath the rollers, will remain at a substantially constant pressure greater thanv the pressure to which the outer ends of the rollers in the fluid pressure spaces 28 and 29 are subjected.

It will be apparent that none of the fluid in. the valve passage 67 will unseat and pass the check valve 72 since the latter is maintained closed; by being subjected to the full pressure of the pump output through return passage 69.

The fluid is displaced from the receding ends. of the fluid pressure spaces 28 and 29 through the ports 52 assen /s and 53, the displaced fluid passing through the axial passages 50 and 51 of the rear timing plate and into the annular groove 54 in the cover, from whence it enters the valve passage 92 between the valve elements of check valves 96 and 97. The displaced fluid will unseat the valve element of check valve 97 for entry into the return passage 94 which leads to the pump 67 The fluid trapped in the inner ends of the recesses 30 is expelled therefrom through the ports 56 and 57 by the inward movement or" the driving rollers as they pass through the receding end of the fluid pressure spaces. The fluid thus displaced from the ports 56 and 57 passes through the axial passages 59 and 60 into the annular groove fill in the cover, and thence into the valve passage 92 in the region between the valve elements of check valves 95 and 96. This fluid then unseats the valve elements of check valves 96 and 97 and passes to the pump through the return passage 94'. It will be apparent that the check valve 96 will maintain the pressure of the fluid displaced from the ports 56 and S7 at a greater pressure than the fluid displaced from ports 52 and 53, whereby the driving rollers will be maintained in continuous contact with the guide track even at the receding ends of the fluid pressure spaces because of the greater pressure applied to the inner ends of the driving rollers.

The pressure applied to the inner ends of the rollers in the region of the pressure spaces 28 and 29 between the ports will remain substantially constant and greater than the pressure upon the outer ends of the rollers.

The motor is reversible and thus the rotor 27 may be driven in the opposite direction by merely reversing the direction of the pump so that the output of the pump is supplied to the cover 20. In this event, the pump output will be delivered to the cover through main passage 9% past check valve 95 through passage 100 and thence to the ports 56 and 57 to maintain the driving rollers in contact with the guide track as they successively enter the fluid pressure spaces. A portion of the fluid also passes check valve 96, being thereby reduced in pressure and delivered through passage 99 in the cover to the ports 52 and 53 for driving the rotor. At the receding ends of the fluid pressure spaces, the fluid is exhausted therefrom through ports 35 and 36 and thence into the valve passage of the body member in the region between the valve elements of check valves 71 and 72. The fluid in the inner ends of the recesses is expelled through ports 39 and 4t) and thence passes into the valve passage 67 of the body member in the region between the valve elements of check valves 70 and 71.

It will thus be apparent that the operation is the same for both directions of rotor rotation and that the driving elements are maintained in continuous contact with the guide track 32 by reason of the fact that the pressure to which the inner ends of the driving rollers are subjected, is greater than the pressure upon the outer ends thereof.

In brief summary and with reference to Figures 1 and 2, the ports 35 and 36 are connected to the pump by the annular grooves 37 and 38, passage 81, a portion of the valve passage 67, and passage 65, these grooves and passages constituting what might be called a main passageway to the ports 35 and 36. The ports 39 and 4-0 connect into the main passageway through grooves 41 and 44 and passage 82, these grooves and passages constituting what might be called a branch passage. The pressure of the fluid to the ports 35 and 36 is, of course, reduced by passage through the check valve 71. It will be understood that the pressure of the fluid delivered to the ports 35 and 36 will be less than that delivered to the ports 39 and 49 by reason of the check valve 71 which serves as a pressure reducing valve. The same is true of the check valve 96 in the cover 20.

All of the valves 95-97 and 7tl-72 are of identical construction for economy of manufacture. However, the check valves 95, 97, 70 and 72 are not required to serve 6 a pressure reducing function in accordance with this invention, but are employed to prevent a reverse flow of fluid.

The drawings and the foregoing specification constitute a description of the improved hydraulic motor in such full, clear, concise and exact terms as to enable any person skilled in the art to practice the invention, the scope of which is indicated by the appended claims.

What we claim as our invention is:

1. A reversible fluid motor comprising a rotor provided with a plurality of driving elements movable inwardly and outwardly thereof in a substantially radial direction, a casing for said rotor including a track for guiding said elements in their in and out movement and provided with a fluid pressure space adjacent said rotor for subjecting the outer ends of said elements to the pressure of the fluid in said space as they pass therethrough, said space having first and second ports respectively at the opposite ends thereof, a first main passage having one end connected to said first port and a second main passage having one end connected to said second port, said passages being adapted to exhaust said space and supply fluid under pressure thereto to drive said rotor in opposite directions and each having means at the other end adapted for connection to a fluid pump, means for supplying fluid under pressure to the inner ends of said elements comprising a first branch passage connected to said first main passage and communicating with the inner ends of said elements when the outer ends thereof pass through the region of said first port, a second branch passage connected to said second main passage and communicating with the inner ends of said elements when the outer ends thereof pass through the region of said second port, check valves in said main passages between said branch passages and the said other ends of said main passages preventing flow toward the said other ends, a return passage for each main passage having one end connected thereto between the port and the branch passage and having the other end connected thereto between the check valve and the said other end of said main passage, a check valve in each return passage preventing flow from the said other end to the said one end thereof, and pressure reducing means in said main passages between said branch passages and said one end of said return passages for providing a greater pressure at the inner ends of said elements than at said ports to maintain said elements in contact with said track.

2. A motor as defined in claim 1 in which each pressure reducing means comprises a check valve spring-biased to closed position and preventing flow toward the branch passage.

3. A motor as defined in claim 1 in which said driving elements are cylindrical rollers rotatably and slidably supported about the periphery of said rotor with their axes extending axially thereof.

4. A reversible fluid motor comprising a casing having a chamber, a rotor supported in said chamber and having circumferentially spaced recesses about the periphery thereof, driving elements supported in said recesses for radial in and out movement, said chamber having an annular peripheral wall adapted to contact the outer ends of said elements, said chamber defining a fluid pressure space along the periphery of said rotor and having first and second main ports respectively at the opposite ends thereof, a first main fluid passage having one end connected to said first port, a second main fluid passage having one end connected to said second port, said passages being adapted to selectively exhaust said space and supply fiuid under pressure thereto to drive said rotor in opposite directions and each having means at the other end adapted for connection to a fluid pump, first and second additional ports in said chamber respectively registering with the inner ends of said recesses when the elements therein pass through the region of said first and second main ports, branch passages extending from said additional ports and respectively connected to said first and second main passages, check valves in said main passages between said branch passages and the said other ends of said main passages preventing flow toward the said other ends, a return passage for each main passage having one end connected thereto between the main port and the branch passage and having the other end connected thereto between the check valve and said other end of said main passage, a check valve in each return passage preventing flow from the said other end to the said one end thereof, and pressure reducing means in said main passages between said branch passages and said one end of said return passages for providing a greater pressure at said additional ports than at said main ports to maintain said elements in contact with the Wall of said chamber.

5. A motor as defined in claim 4 in which each pressure reducing means comprises a check valve springbiased to closed position and preventing flow toward the branch passage.

6. A motor as defined in claim 4 in which each pressure reducing means comprises a check valve preventing flow toward the branch passage, and in which all of said check valves are of identical construction having valve elements spring-biased to closed position.

7. A motor as defined in claim 4 in which said driving elements are cylindrical rollers rotatably and slidably supported in said recesses with their axes extending axially of the rotor.

8. A fluid translating device comprising a device proper having a stator formed with an axially extending through passage, front and rear timing plates at the front and rear ends of said device proper overlying said passage and defining therewith a rotor chamber, a rotor supported in said chamber for rotation and having a plurality of circumferentially spaced recesses in the periphery thereof, driving elements supported in said recesses for radially in and out movement, said chamber having an annular peripheral Wall adapted to contact said elements and guide the same in their in and out movement, said chamber defining a fluid pressure space along the periphrey of said rotor through which the outer ends of said elements pass upon rotation of said rotor, said timing plates having first ports therein respectively registering with said space at opposite ends thereof for the passage of fluid to and from said space, said front timing plate having a second port registering with the inner ends of said recesses who the elements therein pass through the region of the first port in said front timing plate, said rear timing plate having a second port registering with the inner ends of said recesses when the elements therein pass through the region of the first port in said rear timing plate, a body member at the front end of said front timing plate, a cover member at the rear end of said rear timing plate, first and second passages in said body member respectively communicating with the first and second ports in said front timing plate, first and second passages in said cover member respectively communicating with the first and second ports in said rear timing plate, means removably holding said motor proper, timing plates, and members in assembled relation, said members each hav- 3 ing a valve passage and three spring-loaded check val es in end to end alignment in each valve passage, :1 main passage in each member having an end connected to one end of the valve passage therein, a return passage in each member having one end connected to the other end of the valve passage therein and having the other end connected to the main passage therein, all of said check valves being arranged to permit the passage of fluid only in a direction toward the said other end of the associated valve passage, the first passages in said members respectively communicating with the Valve passage therein between the intermediate check valve and the check valve adjacent the said other end of said valve passage, and tile second passages in said members respectively communicating with the valve passage therein between the intermediate checl: valve and the check valve adjacent the said one end of said valve passage.

9. A reversible fluid translating e ice comprising a rotor provided with a plurality of drivin elements mcvable inwardly and outwardly thereof in a substantially radial direction, a casing for said rotor including a track for guiding said elements in their in and out movement and provided with a fluid pressure space adjacent said rotor through which said elements pass upon rotation of said rotor, said space having first and second ports respectively at the opposite ends thereof, a first main passage having one end connected to said first port and a second main passage having one end connected to said second port, said passages being adapted to admit fluid to and withdraw fluid from said space, means for providing fluid under pressure at the inner ends of said elements comprising a first branch passage connected to said first main passage and communicating with the inner ends of said elements when the outer ends thereof pass through the region of said first port, a second branch passage connected to said second main passage and communicating with the inner ends of said elements when the outer ends thereof pass through the region of said second port, check valves in said main passages at the side of said branch passages away from said ports for preventing flow in a direction away from said ports, a return passage for ea 11 main passage having one end connected thereto between the port and the branch passage and having the other end connected thereto at the side of the check valve away from said branch passage, a check valve in each return passage preventing flow from the said other end to the said one end thereof, and pressure reducing means in said main passages between said branch passages and said one end of said return passages for providing a greater pressure at the inner ends of said elements than at said ports to maintain said elements in contact with said track.

References Cited in the file of this patent UNITED STATES PATENTS

Patent Citations
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Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3374749 *Jan 3, 1967Mar 26, 1968Chrysler CorpPorting for balanced hydraulic roller pump
US3824046 *Jan 24, 1973Jul 16, 1974Aro CorpSequential valve for rotary vane air motors
US5030071 *Dec 6, 1989Jul 9, 1991Simpson Neil A ARoller van motor with fluid biassed roller
US5222886 *Mar 20, 1992Jun 29, 1993Mannesmann Rexroth GmbhCheek plate for a vane pump
EP0168268A1 *May 3, 1985Jan 15, 1986André LeroyVolumetric machine with rollers
Classifications
U.S. Classification418/82, 418/225
International ClassificationF03C2/30, F01C21/00, F03C2/00, F01C21/08
Cooperative ClassificationF01C21/0863, F03C2/304
European ClassificationF01C21/08B2D2, F03C2/30C