Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
  • F04B1/00—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders
  • F04B1/04—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinders in star- or fan-arrangement
  • F04B1/0404—Details or component parts
  • F04B1/0413—Cams
  • F04B1/0417—Cams consisting of two or more cylindrical elements, e.g. rollers
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
  • F03C—POSITIVE-DISPLACEMENT ENGINES DRIVEN BY LIQUIDS
  • F03C1/00—Reciprocating-piston liquid engines
  • F03C1/02—Reciprocating-piston liquid engines with multiple-cylinders, characterised by the number or arrangement of cylinders
  • F03C1/04—Reciprocating-piston liquid engines with multiple-cylinders, characterised by the number or arrangement of cylinders with cylinders in star or fan arrangement
  • F03C1/0403—Details, component parts specially adapted of such engines
  • F03C1/0409—Cams
  • F03C1/0412—Cams consisting of several cylindrical elements, e.g. rollers
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
  • F04B1/00—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders
  • F04B1/04—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinders in star- or fan-arrangement
  • F04B1/0404—Details or component parts
  • F04B1/0413—Cams
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
  • F04B1/00—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders
  • F04B1/04—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinders in star- or fan-arrangement
  • F04B1/0404—Details or component parts
  • F04B1/0426—Arrangements for pressing the pistons against the actuated cam; Arrangements for connecting the pistons to the actuated cam
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
  • F04B1/00—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders
  • F04B1/04—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinders in star- or fan-arrangement
  • F04B1/053—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinders in star- or fan-arrangement with actuating or actuated elements at the inner ends of the cylinders
  • F04B1/0531—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinders in star- or fan-arrangement with actuating or actuated elements at the inner ends of the cylinders with cam-actuated distribution members

Definitions

• the invention concerns: a hydraulic machine with radial cylinders having an improved bearing in the crank, i.e. a machine with radial cylinders fixed to its crankcase, advantageously for pressurised hydraulic liquids, in which the respective connecting rod is coupled with the crank through an improved bearing with rolling friction, so as to reduce the parts worked, to simplify the processing and assembly processes, increasing the mechanical performance of the machine and improving its lifetime .
• the state of the art in the specific field of machines with radial cylinders, comprises the hydraulic motors with cylinders oscillating with respect to the body of the motor and with fixed cylinders; these cylinders have connection members of the crank with the piston, like the connecting rods, sliding planes of the base of the piston or sliding shoes of the body of the piston on the crank. It is known that between said sliding shoes and the crank pin a rolling bearing is arranged to reduce the friction and withstand the substantial forces transmitted, consisting of side-by-side rows of rollers between the crank and the outer ring on which the shoes slide.
• the aforementioned hydraulic machines have said rolling bearing formed from an inner raceway coinciding with the outer surface of the crank pin, from an outer ring on the inner surface of which the rows of rollers are coupled, whereas the shoes of the connecting rods of each piston are able to slide on the outer surface.
• crank pin is equipped with end annular abutments for the side containment of the rollers to avoid drift during rolling.
• annular projection is made on which the sides of the rollers of the inner rows rest, to avoid the axial drift of the outer ring with respect to the crank pin.
• the rows of rollers are foreseen in a number equal to the sides of said inner annular projection; thus assembly occurs before the rows of rollers on one side of the annular projection and, then after having correctly positioned the ring with respect to the pin, the remaining rows of rollers are introduced through a side port foreseen in the annular abutment free from the rollers: each roller is introduced individually until the necessary rows of rollers are completed.
• the side port is opened during assembly and closed after assembly thereof. Said port, although closed by a suitable plug, determines sliding on the base of the rollers of the row nearby, due to the imprecision of the plug in its housing after the port has been closed. It has been found that this operating state damages the rollers and reduces its average operating lifetime .
• the inserted flange is equipped with a sealing ring at the inner diameter and is secured to the crank, to prevent it rotating.
• the rollers of the bearing are thus guided in said flanges for their entire bottom face,- thus generating incorrect sliding against their inner surfaces, such as to damage the flanges themselves and the lifetime of the bearing.
• the construction of such a crank is highly mechanically complex without solving the problem of a constructive simplification of the assembly of the roller bearing in the crank and still having the problem of incorrect sliding of the rollers on the inner wall of the flanges.
• Such .a state of the art is susceptible to improvements with regard to the possibility of making a machine for hydraulic liquids that allows a simple construction of the crank, has a reduced number of parts and with less processing and assembly operations, reducing the processing and assembly costs increasing its performance and the lifetime of the machine.
• the invention solves the aforementioned technical problem, by adopting: a hydraulic machine with radial cylinders, comprising cylinders fixed to the body in which the cylinders are circumferentially spaced in the rotation plane of a crank rotating with a drive shaft of the machine; distribution members of the hydraulic liquid and at least one bearing with rolling friction having rows of rollers, arranged between the crank and the sliding shoes of the connecting rods of said cylinders; characterised in that it comprises an outer ring of the rolling bearing held in position by annular support means of the ring and of the rollers; said means being foreseen for an incomplete radial contact of the base of said rollers against said side annular support means; at least one of the annular means being removably applied on the crank. _ Moreover, in a further embodiment, by adopting said side annular support means held by at least one axial stop ring.
• said removable annular support means consisting of at least one ring or fifth wheel equipped, on the side intended to come into contact with the bases of the rollers, with a shoulder with a diameter such as to engage the rollers of the interfacing row for a band of smaller size than the radius of the roller.
• said removable annular support means consisting of at least one ring or fifth wheel with a diameter such as to engage the rollers of the interfacing row for a band of smaller size than the radius of the roller.
• annular support means equipped with at least one inner axial stop ring positioned to contain the rows of rollers in which in the contact between said stop ring and the bases of the rollers an axial support ring is positioned; in at least one of the ends of the crank an outer axial stop ring is foreseen, in contact with the base of the rollers of the interfacing row of rollers between which a support ring is arranged.
• the outer ring of the rolling bearing equipped with the inner axial stop ring positioned with any number (but not zero) of rows of rollers between it and one of the ends of the crank; there is a support ring on both sides of said inner stop ring.
• an inner axial stop ring present on each end of the outer ring of the bearing with rolling friction and having, situated between said ring and the bases of the rollers of the side- by-side rows, a support ring.
• an outer axial stop ring present on each end of the crank and having, situated between said ring and the bases of the rollers of the side-by-side rows, a support ring.
• Figure 1 is a schematic section of a hydraulic motor made according to the invention on the axial plane of the drive shaft containing a cylinder
• Figure 2 is a schematic cross sect.ion of the complete motor containing all of the cylinders
• Figure 3 is a cross section, like Figure 2, limited to the crank and enlarged
• Figure 4 is an axial section, like Figure 1, limited to the crank and enlarged
• Figure 5 is an axial section, similar to the previous one, in which a simplified assembly is illustrated
• Figure 6 is an axial section, like Figure 1, limited to the crank and enlarged, of an embodiment of the present invention equipped with a containment fifth wheel for supporting the end wheels and the outer ring
• Figure 7 is an • axial section, analogous to the previous figure, in which an assembly is illustrated that is simplified, but that avoids the containment fifth wheel making contact with the bearing of the main journal.
• the axial stop ring 13 allows the outer ring 15 on which it is mounted to be positioned axially, with respect to the crank 10. Indeed, the rows of rollers 11, on the outside, are in contact with the outer base of the rollers on one side with the annular projection 16 and on the other side with an outer axial stop ring 17 and with a support ring or fifth wheel 18.
• the outer ring 15 carries, so that they can slide on it in a known way, the shoes 19 of the connecting rods 20, in turn connected with the spherical feet 21 to the respective piston 22 of each cylinder 8.
• the rings 23 hold, in a known way, said shoes
• a drive shaft 24 is equipped with a crank 25 on the surface of which recesses are made, at the ends of said crank, for housing outer stop rings 26 with a support ring or fifth wheel 28 interposed between it and the side-by-side row of rollers, for the side containment of the bases of the rollers in the missing part in the axial stop ring, advantageously of the seeger type and without eyelets a the end, i.e. with reduced radial bulk.
• the number of intermediate rows of rollers 32 can be whatever, in order to complete the filling in width of the rolling surface of the crank 25.
• a drive shaft 3 is equipped with a crank 35 on which at one end 33 of said crank, a shoulder 36 is foreseen between it and the side-by-side row of rollers 37, a support shoulder 38, for the side containment of the outer ring 39 of the rolling bearing, being foreseen on said end of the crank.
• the outer ring 39 is positioned axially to the crank 35 through a support ring or fifth wheel 41, on which a shoulder 40 is
• the number of intermediate rows of rollers 32 can be whatever, in order to completely fill the width of the rolling surface of the crank 35.
• the fifth wheel 41 is located side-by-side on the outside of the mai-n bearing 4 of the crankshaft 3, on which it can slide, with it being foreseen for it to be coupled with the crank with diameter 42 with clearance.
• a drive shaft 3 is equipped with a crank 45 on which, at one end 33 of said crank, a shoulder 36 is foreseen between it and the side-by-side row of rollers 37, and a support shoulder 38, for the side containment of the outer ring 39 of the rolling bearing, is also foreseen on said end of the crank.
• the outer ring 39 is positioned axially to the crank 45 through a support ring or fifth wheel 51, on which a shoulder 50 is foreseen for the side containment of the bases of the rollers of the opposite end row 37 and to allow it to slide correctly.
• the number of intermediate rows of rollers 32 can be whatever, in order to completely fill the width of the rolling surface of the crank 45.
• the fifth wheel 51 is side-by-side on the outside of an outer stop ring 46, housed in the recess 47 made between the crank 45 and the main bearing of the shaft 3 opposite the end 33 of said crank.
• the assembly of the bearing with rolling friction in the crank 10 takes place as follows. After having positioned the outer ring 15 near to the crank 10 the rollers of the two rows 11 and 12 are introduced from the side of the annular projection 16 of said crank; then a support ring 14 and the inner axial stop ring 13, with the appropriate instruments, are introduced in succession into the middle plane recess of the outer ring 15, followed by a second support ring 14. Thus, after having positioned the assembly on the crank 10, the successive rows of rollers 12 and 11 can be introduced, until the completion of said. rows.
• the inner axial stop ring 13 acts as a projection for stopping the drift of the outer ring 15 with respect to the middle plane of the crank 10, allowing correct .operation of the shoes 19 on the outer surface of said outer ring.
• the position of the axial stop ring 13 can be varied from what has been depicted in the figures; indeed, if a different number of rows of rollers has to be foreseen the stop ring can be positioned with an number (but not zero) of rows of rollers between it and the ends of the crank.
• the movement of the stop ring is only possible by foreseeing the recess in the suitable point on the inner diameter of the ring 15 between the outer rolling raceways of the rows of rollers 11 or 12.
• the inner axial stop ring 13 can be replaced with an axial stop ring 30 at each end: in this way the outer rows of rollers 27 and the inner ones 32 can occupy the entire axial generatrix of the rolling surface of the rollers in. the crank 25, completely exploiting its length.
• Figures 6 and 7 are extremely cost-effective and easy to apply, taking care to make the support rings or fifth wheels 41 and 51 from hardened material with high mechanical strength and suitable for the sliding of the bases of the rollers.
• the bearing with rolling friction in this way has a longer lifetime, having the rolling bodies (rollers) correctly guided with axial abutment; moreover, the performance of the axial abutment is much quicker and simpler that what occurred previously: now it is much easier to make a recess at the sides of the raceways of the rollers than the processing of the integral axial projection of the prior art.
• the group of the rows of rollers 11 and 12 can be pre- assembled before the definitive movement on the outer surface o.f the crank 10 : before this operation was prevented by the double axial support projection present in the crank of the prior art.
• an integral axial abutment, replacing an inner axial stop ring 30, can be made in an end of the outer ring 15, 29 of the bearing with rolling friction.

Priority Applications (1)

Applications Claiming Priority (2)

Publications (1)

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ID=36084202

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Cited By (3)

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Citations (6)

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• 2006
  • 2006-09-26 WO PCT/IT2006/000686 patent/WO2007036972A1/en active Application Filing
  • 2006-09-26 CN CN200680035075.7A patent/CN101278122B/zh not_active Expired - Fee Related

Patent Citations (6)

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