EP2531720A1 - Subassembly forming a hydrobase for hydraulic motors, and assembly method - Google Patents

Abstract

The present invention relates to a subassembly for forming a hydraulic motor after assembly onto an assembly including a shaft (400), said subassembly including a cover (100) forming a housing element, a multilobe cam (200), a cylinder block (300) opposite the cam (200), pistons (500) guided so as to slide radially within the respective cylinders of the cylinder block (300) and bearing on the lobes of the cam (200), and a valve (600) intended to apply pressurized fluid to said pistons (500) in series, characterized in that said subassembly includes means (152, 154) for temporarily attaching the cylinder block (300) to the cover (100) and means (185) for accessing an element (610) of the valve (600) through the cover (100) in order to enable, during installation, the angular positioning of said element (610) with respect to the shaft (400), followed by the attachment thereof to the shaft (400). The present invention also relates to a method for assembling such a hydrobase.

Description

 HYDROBASE-FORMING SUBASSEMBLY FOR HYDRAULIC ENGINES AND METHOD OF ASSEMBLY

 The present invention relates to the field of hydraulic motors.

 More specifically, the present invention relates to the field of hydraulic motors with radial pistons.

 The applicant has already proposed many models of such radial piston hydraulic motors.

 As shown in longitudinal section in FIG. 1 and in cross-section in FIG. 2, radial piston hydraulic motors of the aforementioned type generally comprise in a housing 10 comprising two half-housings 10a and 10b and a cam 20:

 said multilobe cam 20, preferably formed on the inner surface of an element 22 of the casing 10,

a cylinder block 30 mounted relative rotation in the casing 10,

 a shaft 40 connected to rotation with the cylinder block 30,

 pistons 50 guided with radial sliding in respective cylinders 52 of the cylinder block and bearing on the lobes of the cam 20, and

a distributor 60 adapted to successively apply in a controlled manner a fluid under pressure on the pistons 50, so that the successive pressing of the pistons 50 on the lobes of the cam 20 causes the relative rotation of the cylinder block 30 and the elements which are connected relative to the housing 10.

 To obtain a hydraulic motor, all the parts are assembled permanently: the cam 20 is fixed by bolting between the two housings 10a and 10b, and the shaft 40, carried by the housing 10b, itself carries the block -cylinders 30.

In addition, the pistons are stapled in the cylinders and are thus held in their housing when the cylinder block is inserted into the cam. Finally, the distributor 60 is held in place in the housing 10a by angular positioning means. However, in many cases, it is desirable to provide not such a complete motor equipped with its shaft 40, but only a subassembly as illustrated in Figure 3a including the basic elements of the engine, to namely cam 20, cylinder block 30, pistons 50 and distributor 60, in a housing 10a, also called cover, which constitutes a half-casing for the final engine. Such a subset constituting an incomplete motor is intended to be inserted into the kinematic chain of a user by engagement on a shaft and / or on a complementary housing element 10b that can contain a bearing. More generally, this subassembly comprises rotating elements and fixed elements (for example respectively a cylinder block and a distributor on the one hand, and a cam on the other hand). To constitute a complete motor, these elements are then assembled respectively to rotating elements and complementary fixed elements (for example respectively a shaft on the one hand and a housing element comprising a bearing on the other hand).

 Such a set is generally referred to as a hydrobase by the Applicant. However, before fixing the hydrobase to a shaft and a half-casing may or may not contain a bearing, it can not be maintained in the mounted state as shown in Figure 3a. In reality, it is in the form of a collection of unrelated pieces, as in Figure 3b. For example, the cam 20 is not connected to the lid 10a, and the cylinder block 30 is not held in place.

 Despite strong demand for such subsets, the means currently available on the market do not always give complete satisfaction.

Thus, a difficulty in using such a hydrobase, delivered in the form of a collection of unassembled parts, is the risk of loss, deterioration or mixing of these parts, as well as their pollution or poor mounting by their user. A main object of the present invention is to improve the means known in the state of the art to facilitate in particular the engagement of such subsets on a shaft or bearing.

 Another object of the invention is to provide a hydrobase in assembled and sealed form, prior to its mounting on a subassembly comprising a shaft and a housing that can contain a bearing, thus allowing its transport without damage or pollution, and with prepositioned elements according to the arrangement chosen by the manufacturer.

 The present invention applies in particular to the case of implantation of a motor having a fixed shaft relative to the frame of the machine and a rotary housing, for example integral with a wheel.

 Those skilled in the art know that particularly in this case the aforementioned purpose is difficult to achieve because, on the one hand, of the weight of the hydrobases and, on the other hand, that most often such hydrobases require a mounting in blind on the shaft or support bearing of the machine to equip.

 The aforementioned object is achieved within the scope of the present invention by means of a subset or hydrobase intended to form a hydraulic motor after assembly on an assembly comprising a shaft, which subassembly comprises a cover forming a housing element, a cam multilobe, a cylinder block placed opposite the cam, pistons guided to radial sliding in respective cylinders of the cylinder block and bearing on the lobes of the cam and a distributor for successively applying a fluid under pressure on said pistons, characterized in that it comprises means for temporarily fixing the cylinder block on the lid and means for accessing a dispenser element, through the cover, to allow, during installation, the angular orientation of the this element relative to the shaft, then its attachment to the shaft.

According to another advantageous characteristic of the invention, the subassembly or hydrobase comprises means ensuring a pre- angular positioning and / or fixing of the cam on the lid, for example by means of pins or screws.

 The present invention also relates to a method of assembling the subassembly or hydrobase according to the present invention, to form a hydraulic motor.

 Other features, objects and advantages of the present invention will appear on reading the detailed description which follows, and with reference to the appended drawings, given as non-limiting examples and in which:

FIG. 1 previously described represents a longitudinal sectional view of a hydraulic motor known from the state of the art according to the section planes referenced I-I in FIG. 2,

 FIG. 2 represents a cross-sectional view of the same hydraulic motor according to the section plane referenced II-II in FIG. 1;

- Figure 3a previously described is a longitudinal sectional view of the arrangement of parts of a known hydrobase of the state of the art in assembled form, and before assembly to a subassembly comprising a shaft and a crankcase element .

 FIG. 3b represents a view of the collection of parts constituting a hydrobase before their assembly,

 FIG. 4 represents a longitudinal cross-sectional view of the axis 0-0 of a hydrobase according to one embodiment of the present invention, and in particular illustrating a means for temporarily fixing the cylinder block on the lid,

- Figure 5 shows a longitudinal sectional view of a hydrobase according to an embodiment of the present invention, according to a different sectional plane of Figure 4, and illustrates in particular the final attachment of a dispenser part on a tree,

FIGS. 6 and 7 are perspective views of two embodiments of a hydrobase according to the present invention and more specifically illustrate two particular embodiments of the means of access through the lid to an element of the dispenser in order to allow the angular orientation of this element during installation, FIG. 8 represents a partial exploded perspective view of a hydrobase according to the present invention and more precisely illustrates angular indexing means between the cam and the lid of a hydrobase according to the present invention,

FIGS. 9 and 10 represent two lateral lateral views, transverse and axial respectively, of a single hydrobase according to the present invention, assembled by its provisional fixing means and closed by a closing plate, and

 - Figures 11 to 26 show successive views illustrating a method of assembling a hydrobase according to the present invention on an assembly comprising a shaft and a housing member of a machine to be equipped.

 As indicated above, the subassembly or hydrobase according to the present invention essentially comprises a cover housing element 100, a cam 200, a cylinder block 300 and a distributor 600.

 Each of these elements cover 100, cam 200, cylinder block 300 and distributor 600 may be the subject of many embodiments known in themselves to those skilled in the art corresponding to conventional hydraulic motors and hydrobases, piston engines radial and multilobe cams, also called high torque and low speed motors.

 As a result, the precise structure of these cover elements 100, cam 200, cylinder block 300 and distributor 600 will not be described in detail later.

 Note, however, that the hydrobase according to the present invention is centered on a 0-0 axis of rotation.

 The lid 100 constitutes a tight wall transverse to the axis 0-0 which covers a complete lateral side of the hydrobase. Its contour is preferably circular.

The cam 200 is preferably formed of a ring 201 adjacent to the axially inner face of the cover 100 at the radially outermost peripheral zone of the cover 100. On its radially inner surface, the cam 200 has, as can be seen for example in FIG. 8, a series of regular lobes 210 equi-distributed around the axis 0-0. Each of the lobes 210 generally has a sinusoidal type appearance.

 The cam 200 is connected to the cover 100. It is also attached to the rotating hub of the wheel of the machine that carries the rim.

 The cylinder block 300 is placed inside the ring 201 constituting the cam 200. It defines a plurality of cylinders 302 oriented radially with respect to the axis 0-0 and opening on the outer peripheral face of the cylinder block 300 in 200. A piston 500 is mounted to slide radially respectively in each of the cylinders 302. It bears on the radially inner surface of the cam 200.

 The cylinder block 300 has a central bore through which the cylinder block 300 is engaged on the end of the shaft of the machine to be equipped. Furthermore, this bore has a series of complementary longitudinal grooves splines 402 provided on the end of the shaft to provide angular indexing of the cylinder block 300 on the shaft, once the installed hydrobase.

 The distributor 600 is designed to apply in a controlled manner a fluid under pressure successively to each of the pistons 500, more precisely in the radially inner chamber of the cylinders 302 adjacent the pistons, so that the successive support of the pistons 500 on the lobes of the piston. cam 200 causes the relative rotation of the cylinder block 300 and the elements which are connected to it relative to the lid 100, when used on an equipped machine.

 To this end, there is an asymmetry between the number of lobes 210 formed on the cam 200 and the number of associated pistons 500 located in the cylinder block 300.

By way of non-limiting example, according to the illustration given in FIG. 2, which can be repeated in this respect in the hydrobase according to the invention, six lobes 210 are provided on the cam 200 and eight associated pistons 500. As illustrated in FIGS. 4 and 5, the dispenser 600 is formed of two pieces: a central piece 610 or "against-ice" intended to be placed facing the end of the shaft and to be fixed thereto and an outer piece 620 or "ice" placed around the central piece 610, rotatably connected to the lid 100 by any appropriate means, for example a finger or a locking pin to allow longitudinal sliding between the outer piece 620 and the cover 100.

 Alternatively the indexing means provided between the cover 100 and the part 620 may be formed of a mechanism such as an Oldham seal ensuring the transmission without play of a rotational movement between the cover 100 and the part 620 keeping their axes parallel but not necessarily concentric. Such a mechanism may be formed of a washer perpendicular to the axes of rotation comprising radial oblong slots which respectively receive pins integral with the cover 100 and pins integral with the outer part 620. This means allows a limited sliding along the directions perpendicular to the axis of the motor, while ensuring a precise angular setting.

The outer part 620 has a transverse face 622 contiguous to a complementary face of the cylinder block. The central piece 610 has a series of channels having longitudinal sections 611, 612, 613 which open into respectively complementary channels 460, 462, 464 formed in the shaft 400 to provide the functions of supply and drain and cross sections. 614, 615 which open on the radially outer face of this central piece 610 at peripheral annular grooves, facing the outer part 620. The latter has channels with transverse sections which open opposite annular grooves related to the transverse sections 614, 615 of the central piece 610 and longitudinal sections which open opposite the supply ports formed in the piston chambers of the cylinder block 300. In FIG. 4, the channel 460 represents a supply channel of the distributor 600, the channel 462 represents a channel carrying the return fluid of the distributor and the channel 464 represents a drain channel which ensures the return of the leaks.

 The general operation of such a hydrobase being known to those skilled in the art, it will not be described in more detail later.

 In use, the cylinder block 300 is rotatably connected to the shaft of the machine to be equipped and is rotatably fixed relative to the central part of the distributor 600. The shaft is of course not part of the hydrobase, and has been shown in Figures 4 and 5 for a better understanding of the hydraulic interface between the hydrobase and the rest of the machine. The feeding of the plunging chambers of the pistons by a fluid passing through channels formed in the shaft and the distributor ensure the rotational drive of the cam 200 relative to the cylinder block 300 and forming the cover 100, of the workpiece External distributor 620 and all the items related to them.

 Preferably, the section of the longitudinal sections of the channels formed in the outer part 620 of the distributor, evolves along the length of these sections, to generate, during the pressurization of the fluid, a force that forces the external part 620 to bear axially against the face facing the cylinder block 300 to ensure a relative seal at this level and prevent fluid leakage.

 If necessary, the biasing of the outer part or ice 620 against the opposite side of the cylinder block 300 may be reinforced by springs 630. Such an arrangement improves the operation of the engine during the first moments after the application of the hydraulic pressure .

 The sealing at the level of the communication between the channels of the two parts, central 610 and external 620, of the distributor, is provided by seals or any equivalent means, for example segments made of cast iron or plastic.

According to an essential characteristic of the invention, as indicated above, the hydrobase comprises means 150 of provisional fixing of the cylinder block 300 on the cover 100, as well as access means 180, through the cover 100, to an element of the distributor 600 in order to allow the angular orientation of this element during the installation with respect to the tree that receives the hydrobase.

 More precisely still, according to the particular nonlimiting embodiment illustrated in FIG. 4, such temporary fixing means of the cylinder block 300 on the cover 100 are formed for example of two screws or bolts 152, 154 engaged in diametrically opposite bores. formed in the cover 100 opposite two respectively associated holes formed in the cylinder block 300.

 Those skilled in the art will readily understand from examining the appended FIG. 4 that these fixing means 152, 154 make it possible to angularly preposition and maintain the cylinder block 300 firmly relative to the distributor 600 and to the lid 100, before any use.

 Of course, as will be discussed later, such fastening means 152, 154 must be removed before using the engine hydrobase.

 The means 180 allowing access to the distributor 600 through the cover 100 may be formed of different embodiments. They are preferably formed of an opening 182 formed in the center of the cover 100 and passing therethrough, associated with a closure flap 184 fixed on the cover 100 by any suitable removable means.

 According to FIG. 6, the fastening means of the shutter

184 are formed of a plurality of screws 186 equi-distributed in holes formed in the flap 184 and cooperating with complementary threaded holes formed on the cover 100.

 According to Figure 7, the closure flap 184 is fixed using an elastic ring 187 circlip type (™) or any equivalent means.

Note the presence of a seal 188 between the closure flap 184 and the opposite face of the lid 100. As illustrated in FIG. 8, preferably in the context of the invention, it is furthermore provided with means of pre-positioning and / or fixing of the cam 200 on the cover 100, for example in the form of pins 202 or screws oriented parallel to the axis 0-0 and interfering with both the cam 200 and the cover 100.

 The presence of access means to the distributor 600 through the cover 100 angularly directs the distributor 600 to align it correctly with respect to supply channels and / or drains from the shaft.

 Preferably, the hydrobase according to the present invention is further provided with plugs making it possible to seal all the bores made in the cover 100, in particular those intended to receive fastening means 152, 154. Thus the bores mentioned above may serve as purge orifices for subsequent maintenance.

 It will also be noted on examining FIG. 9 that, preferably, the hydrobase is closed, before being installed on the associated shaft, by a plate 190 situated on the face of the cam 200 opposite to the cover 100. This plate 190 is fixed using any suitable means, for example using a plurality of bolts 192 and nuts 194 complementary.

 Such a plate 190 can also be the subject of many embodiments. It is preferably a simple flat disk of the same external diameter as the cam 200.

 We will now describe the method of assembling a hydrobase according to the present invention on an associated assembly of a machine, comprising a shaft and a housing element which may comprise a bearing.

The hydrobase, before assembly to the receiving machine, is as in Figures 9 and 10 in the form of a block preassembled by temporary fixing means. This block includes all the elements mentioned above, and already positioned relative to each other in their final mode of operation on the receiving machine, with the exception of the angular adjustment of the distributor with respect to the receiving shaft.

 In this context, the lid 100 of the hydrobase is for example intended to be secured to the movable rim of a wheel, the aforementioned complementary shaft being in turn fixed relative to the frame of a machine.

 Firstly, as illustrated in FIG. 11, it is necessary to remove the closure plate 190 by removing the fastening means 192, 194.

 In parallel, as illustrated in Figures 12 and 13, the frame 410 of the machine and more specifically the output shaft 400 which preferably comprises longitudinal grooves 402, can be equipped with any suitable accessory, for example a ring 404 forming bearing.

 In order to facilitate the positioning of the hydrobase facing the frame, preferably it is provided with support rods 450 parallel to the axis 0-0 engaged for example in complementary bores 412 formed in the frame 410 with a corresponding spacing to complementary bores formed in the hydrobase, more precisely through the cam 200 and the outer periphery of the lid 100.

 Thus, as illustrated in Figures 16 and 17, the hydrobase without its closure plate 190 can be engaged on the rods 450 to facilitate handling by transferring the weight of the hydrobase in part on the rods 450. The use of such rods 450 also facilitates the centering of the hydrobase on the axis of the shaft 400.

The hydrobase is then pushed to axial sliding towards the corrugated shaft 400. As shown diagrammatically in FIG. 18 by the arrows OA in the event that the grooves 402 of the shaft 400 are not aligned with the complementary splines provided. on the inner periphery of the cylinder block 300, the installer proceeds to a relative angular orientation of the hydrobase and the shaft 400 to engage the cylinder block 300 on said grooves 402 of the shaft 400. The temporary support rods 450 can then be removed as illustrated in FIG. 19 and replaced by bolts or fixing screws 110, 112 as shown in FIG.

 It is then necessary to remove the fixing means of the cylinder block 300 by loosening the screws 152, 154.

 For this purpose, as illustrated in FIGS. 21 and 22, the hydrobase may be equipped with a stirrup 156 placed on the external surface of the lid 100, in diametrical position, and having at its ends eyelets in which are engaged the rods of the screws 152, 154. It is sufficient, once the screws 152, 154 loosened, remove the stirrup 156 to easily extract the screws 152, 154. The cylinder block 300 is then disengaged from the cover 100 to allow its relative rotation.

 The access means to the distributor 600 are thus also released. If necessary, it may be, as illustrated in FIGS. 21, 22, a temporary closure flap 185 released automatically when the caliper 156 is withdrawn.

 It may still be the final closure flap 184 assembled by any appropriate means, for example by means illustrated in Figures 6 and 7.

 The installer then proceeds as shown in FIGS. 23 and 24 to the angular orientation of the distributor 600 with respect to the shaft 400 in order to align the supply and drain channels of the distributor element with respect to Channels formed in the shaft 400. Then, the distributor element 600 is fixed on the axial end of the shaft 400 by screws 602, 604.

 Finally, as illustrated in FIGS. 25 and 26, it remains to seal the closing shutter 184 in a sealed manner and to seal with sealing plugs possibly forming a purge 122, 124, the orifices previously receiving the fixing means of the cylinder block 300.

Of course, the present invention is not limited to the embodiments described above and illustrated in the accompanying figures, but extends to any variant within its spirit. By way of example, the fixing means of the distributor element 600 called against ice on the axial end of the shaft, formed by several screws 602, 604 according to FIG. 24, can be replaced by a single bolt, to allow a saving of time of assembly, as well as a saving of place.

 The present invention makes it possible to avoid disassembly / reassembly of the components and saves installation time by improving the quality and reliability of the engine on the machine.

 The hydrobase according to the present invention forms a cartridge that can be used in particular from an end-of-line test bench until assembly on the machine of a user.

 The hydrobase according to the present invention can be equipped with any suitable accessory, for example a brake.

 The present invention allows rapid assembly of the hydrobase on any machine, as well as any disassembly that may be necessary and in complete safety. It guarantees thanks to the simplicity of the means proposed an operational package at the end of the assembly. It also allows easy maintenance.

 According to an alternative embodiment, the hydrobase according to the present invention can be equipped with a hydraulic brake. Such a brake being known in itself, it will not be described in detail later.

Claims

A subassembly for forming a hydraulic motor after assembly on an assembly comprising a shaft (400), which subassembly comprises a cover (100) forming a housing element, a multilobe cam (200), a cylinder block ( 300) placed opposite the cam (200), pistons (500) guided in radial sliding in respective cylinders of the cylinder block (300) and bearing on the lobes of the cam (200) and a distributor (600) for applying successively a fluid under pressure on said pistons (500), characterized in that it comprises temporary fastening means (152, 154) of the cylinder block (300) on the cover (100) and means (185) access to an element (610) of the distributor (600), through the cover (100) to allow, during installation, the angular orientation of this element (610) relative to the shaft (400) ), then its fixing on the shaft (400).  2. Subassembly according to claim 1, characterized in that it comprises means (202) providing an angular pre-positioning and / or a fixing of the cam (200) on the cover (100), for example to using pins or screws.  3. Subassembly according to one of claims 1 or 2, characterized in that the distributor (600) is formed of two parts: a piece (610) central to be placed opposite the end of the shaft and to be attached thereto and an outer piece (620) placed around the central piece, rotatably connected to the cover (100) by any suitable means, for example a finger or a locking pin. 4. Subassembly according to one of claims 1 to 3, characterized in that the central piece (610) has a series of channels having longitudinal sections which open into respectively complementary channels formed in the shaft to ensure the feeding and drain functions and transverse sections which open out to the radially outer face of this central piece (610), at peripheral annular grooves, facing the piece (620), while the outer piece (620) has channels which have transverse sections which open opposite the annular grooves connected to the transverse sections of the central piece (610) and longitudinal sections which open opposite the supply ports formed in the piston chambers of the cylinder block (300).  5. Subassembly according to claim 4, characterized in that the section of the longitudinal sections of the channels formed in the outer part (620) of the distributor (600) evolves along the length of these sections to generate during pressurization. fluid a force biasing the outer member (620) axially against the facing face of the cylinder block (300).  6. Subassembly according to one of claims 4 or 5, characterized in that it comprises springs urging the outer part (620) of the distributor (600) against the cylinder block (300).  7. Subassembly according to one of claims 1 to 6, characterized in that the means (180) allowing access to the distributor (600) through the cover (100) comprise an opening (182) formed in the center cover and through it, associated with a removable closure flap (184).  8. Subassembly according to claim 7, characterized in that it comprises fastening means of the closure flap (184) consisting of a plurality of screws (186).  9. Subassembly according to claim 7, characterized in that it comprises means for fixing the closure flap (184) formed of an elastic ring (187). 10. Subassembly according to one of claims 1 to 9, characterized in that it comprises a stirrup (156) removable having eyelets in which are engaged the screw rods (152, 154) forming fixing means temporary cylinders block relative to the lid (100). 11. Subassembly according to one of claims 1 to 10, characterized in that it comprises closure plugs bores made in the cover (100) for receiving the block fixing means (152, 154). cylinders (300) on the cover (100), which plugs are positioned after removal of the temporary fastening means (152, 154).  12. Subassembly according to one of claims 1 to 11, characterized in that it comprises a plate (190) removably attached to the face of the cam (200) opposite the cover (100).  13. A method of assembling the subassembly according to one of claims 1 to 12, on a shaft (400) characterized in that it comprises the steps of:  - removing a closure plate (190) located on the face of the cam (200) opposite the cover (100), - Engage the hydrobase on the end of the shaft (400),  - removing the provisional fastening means (152,154) of the cylinder block (300) relative to the cover (100),  withdrawing the means (185) giving access to the distributor (600),  angularly orienting the distributor (600) with respect to the end of the shaft (400) so as to align the supply and drain ducts formed in the shaft (400) with complementary ducts formed in the distributor ( 600)  - fix the central part (610) of the distributor (600) relative to the end of the shaft, - Close the access means formed in the cover (100).  14. The method of claim 13, characterized in that it comprises the intermediate step of placing support rods (450) on the housing of the machine to serve as a support to the housing of the hydrobase (100) during the engagement on the shaft (400). 15. Method according to one of claims 13 or 14, characterized in that it comprises the additional step of closing the orifices receiving the temporary means for fixing the cylinder block (300) relative to the cover (100) by means of bleed plugs (122, 124).