ES2248675T3 - SEPARABLE HEADS FOR PUMPS AND HYDRAULIC MOTORS. - Google Patents

Abstract

Separable heads for motors and hydraulic pumps of the type comprising a body (4), containing an overhanging shaft (7) and a shaft (10) disposed within said body, said shafts being mutually engaged by gears (8, 9), a cover (2) and a base (3); an open cavity (6) for the projecting shaft being provided in said base (3), and oil drainage means (26) being present in said cover (2), characterized by the fact that on the faces of the base ( 3) and of the cover (2) which are directed towards the body (4) respective interconnected groove networks (22) being provided that are adapted to accommodate respective deformable joints (23) made of a material such as rubber, and by the fact that said network of grooves (22) of the base (3) and of the covers (2) comprises cavities for rotationally supporting said shafts (17, 19, 20), which extend with peripheral holes facing, a groove that it is external to the cavities and is substantially formed with the figure of an eight with two mutually separated connecting portions, and a diamond shaped perimeter groove with rounded corners that is connected to the groove in figure eight by short portions.

Description

Separable heads for pumps and motors Hydraulic

The present invention refers to heads separable for pumps and hydraulic motors.

Conventional gear pumps and motors they comprise a body that is comprised between two heads, which It contains an internal axis and an outstanding axis, which are parallel and have respective coupled gears adapted there; such pumps and motors are manufactured so that the direction of rotation of the shaft is determined during assembly according to the requirements of the final user.

In practice, the manufacture of a machine Hydraulics of the type described require the manufacturer to use different components according to the type of intended use: a pump done can be right or left or also reversible; of the In the same way, an engine can assume the same three settings, which depend in this case on the oil flow.

In order to minimize the components which differ according to the end use, manufacturers have evolved in the manufacture of pumps and motors in which a sophisticated system ball valve, arranged inside a sealing sleeve that is properly profiled to ensure tightness against excessive pressures on its two surfaces, allows, using few different parts compared to standard models, make a Same machine suitable for rotating in both directions.

The choice shared by the majority of manufacturers today is to make the required components for the bidirectionality of the machine reside within the body of machine.

This solution is disadvantageous if necessary. act on those elements to change the type of operation according to new requirements that have arisen (in the few cases in which this is actually possible): in fact it is necessary to disassemble the machine completely and remove the fixings provided in order to ensure the positioning of the ball valve. Rarely can the user convert a machine purchased with certain features on a machine that has features different.

The arrangement of the components required for bidirectionality within the body also makes them less accessible to a poorly specialized operator who performs operations for disassembly, modification and subsequent machine assembly.

GB-1 257 92 shows pumps Hydraulic gears with separable heads.

GB-769763 shows together provided on both sides of coupled gears.

The objective of the present invention is to avoid the aforementioned drawbacks and meet the mentioned needs providing separable heads for pumps and hydraulic motors in those that are easy to make the modifications required to Change operational characteristics.

Within this objective, an object of the present invention is to provide a line of machines, pumps and motors that have the largest number of common parts and differ only in some constructive details of some of its parts.

Another object of the present invention is to provide a structure that is simple, relatively easy to provide in the practical, safe in use, effective in operation, and relatively low in cost.

This objective and these objects are achieved by the present separable heads for motors and hydraulic pumps, as defined in the claim.
dedication 1.

Other features will be apparent from better mode from the detailed description of an example of preferred but not exclusive embodiment of separable heads for hydraulic motors and pumps, according to the invention, illustrated by non-limiting example in the accompanying drawings, in which:

Figure 1 is a sectional view, taken at along two perpendicular planes, of a machine on which the heads according to the invention are adapted;

Figure 2 is a sectional side view, taken along a substantially central plane, of a machine on which the heads according to the invention are adapted;

Figure 3 is a side view of a machine on which the heads according to the invention are adapted;

Figure 4 is a sectional view, taken at along line IV-IV of Figure 3, of a machine on which the heads according to the invention are adapted;

Figure 5 is a plan view of the lid according to the invention for the exemplary embodiment with recovery internal;

Figure 6 is a sectional view, taken at along line VI-VI of Figure 5, for the example of performing internal recovery;

Figure 7 is a sectional view, taken at along line VII-VII of Figure 5, for the example of performing internal recovery;

Figure 8 is a set of views of cover perspective for the embodiment example of internal recovery;

Figure 9 is a plan view of the lid according to the invention for the example of suitable embodiment both for external drainage as for internal recovery;

Figure 10 is a sectional view, taken at along the X-X line of Figure 9, for the exemplary embodiment suitable for both external drainage and for internal recovery;

Figure 11 is a sectional view, taken at along the line XI-XI of Figure 9, for the exemplary embodiment suitable for both external drainage and for internal recovery;

Figure 12 is a perspective view of the cover, provided with accessories for the embodiment suitable for both external drainage and recovery internal;

Figure 13 is a set of views of lid perspective for the suitable embodiment example both for external drainage as for internal recovery;

Figure 14 is a plan view of the lid according to the invention for the recovery embodiment example internal with ball valve;

Figure 15 is a sectional view, taken at along the line XV-XV of Figure 14, for the internal recovery embodiment example with valve balls;

Figure 16 is a sectional view, taken at along line XVI-XVI of Figure 14, for the internal recovery embodiment example with valve balls;

Figure 17 is a set of views of lid perspectives for the embodiment example of internal recovery with ball valve;

Figures 18, 19, 20 and 21 are views of the cycle of operations required to change the direction of rotation in machines using the heads according to the invention.

With reference to the figures, the number of reference 1 generally designates a machine provided with separable heads for motors and hydraulic pumps according to invention. The separable heads are constituted by the lid 2 and the base 3, which are rigidly held against the ends of the body 4 using screws with locknuts 5.

Through a hole 6 provided in the base 3, the projecting shaft 7 extends inside the internal compartment 4a of the body 4, where the gear 8, adapted on the shaft protruding 7, engages the gear 9 adapted on the shaft internal 10. The body 4 has, on its opposite faces, two ducts of access 11 for the entry and exit of the oil with respect to the 4th compartment; the conduit in which oil is present at high pressure is the one designated by reference number 11a, it is that is, the conduit that has the smallest cross section, while the conduit in which the oil is present under pressure low is designated by reference number 11b and has a major cross section.

The two axes 7 and 9 are held mutually in position using the end bushings 12, which have substantially the shape of an eight to accommodate, in each of the two cavities provided, one of the two axes 7 and 9 while At the same time they allow you to rotate around your own axis. The axial distance between the two bushings, when machine 1 is completely assembled, it is slightly larger than the width of the 8 and 10 gears, to allow their rotations.

The hole 6 of the base 3 has a inner region 13, whose diameter approximates the diameter of the axis 7 and is adapted to hold it in position, and an outer region 14, which has a larger diameter and is adapted to accommodate a sealing ring bearing 15 which is adapted to prevent oil leak.

A channel 16 connects region 14 of hole 6 to the blind cavity 17 that accommodates the end of the inner axis 9. The channel 16 acts as a path for oil, which when it reaches the barrier constituted by the sealing ring 15, crosses said path and reaches the other end of the machine 1, in the lid 2, flowing in the axial channel 18 provided on the axis 9.

Cap 2 has two cavities, designated by the reference numbers 19 and 20, which are similar to cavity 17 of the base 3 in terms of dimensions and are connected to each other through a conduit 21; the portions of cavities 19 and 20 that they face the area where conduit 21 is provided they have two gaps, designated by reference numbers 19a and 20a respectively, in order to facilitate the outflow of oil.

Observed in plan view, cover 2 and base 3 have 22 interconnected slot networks (much less deep that cavities 17, 19 and 20), which accommodate particular joints 23, that are formed to fill the cavities that make up the network 22 to retain a small perimeter portion of its profile that protrudes and ensures tightness when lid 2 and base 3 are fixed against the body 4. The joint 23 forms two cavities complementary 24 and 25 that are outlined as a circular sector with an obtuse central angle; during the operation, one such Cavities are at high pressure and the other is at low pressure.

In order to allow the oil to drain, the lid 2 can have, in one of the two complementary cavities 24 or 25, an opening 26 that is connected to the bottom of the conduit 21 for connect cavities 19 and 20.

The opening 26, if not used for drainage internal oil, can be closed by a plug 27; in this case, the opening 26 must be provided with a thread 26a.

Alternatively, drainage can be achieved by a channel 28 in the outer wall of the lid 2 that interferes with the cavity 19 and is a passageway along part of its extension; oil can flow out of machine 9 through channel 28. Channel 28 can also be threaded; in this case, it becomes suitable to accommodate a screw cap 29 with an o-ring to close said channel of
drain 28.

The operation of the invention is as follows: when machine 1 is used as a pump, shaft 7 is moved externally by any power source; the oil that reaches the pump 1 from the low pressure line 11b reaches the mutually engaging gears 8 and 10. The direction of rotation of the shaft 7 is such that the gears push the oil towards the high pressure duct 11a. Axially, the oil cannot come out of pump 1 along axis 7 due to the presence of the bearing and sealing ring, which prevents oil leakage, generally designated by reference number 15. The oil that flows to the base along axis 7 flows back to the lid a along channel 16, which connects region 14 of hole 6 with the cavity 17, and the axial channel 18, which is present in the shaft 9.

The oil can be drained according to two principles different: drainage with internal recovery and external drainage.

In drainage with internal recovery, the opening 26 connects the complementary cavity 24, located in the oil inlet region, to conduit 21, allowing oil follow a path at the end of which is again at entry 11, thus allowing to summarize the work cycle.

In the external drain, the opening 26, if provided, it is closed by the cap 27 and the oil to be drained can flow freely out through the channel 28.

A third embodiment, which uses private bushings 12 provided with ball valves, allows provide internal recovery drain with opening 26 closed by the plug 27 and the channel 28 closed by the screw cap 29 with o-ring.

The constructive architecture of machine 1 is such that the direction of rotation can be changed simply following the operations shown in sequence in Figure 6. Starting for example with a right-hand unidirectional pump, it is it is necessary to unscrew the screws 5, remove the base 3 and remove one of the two bushings 12 and the pair of axes 7 and 9. Once it is The two axes have been exchanged, pump 1 can be reassembled With the reverse process. The device obtained with the operations described is a left-hand unidirectional pump.

It would proceed in the same way in the case of a engine.

The seats for balancing joints and containment are provided on the bases and on the lid, and therefore only these parts determine the direction of rotation and the type of product; all other components, bushings, pair of Gears and body are unified.

The sealing rings adapted to the shafts are not can withstand high pressures and therefore the chamber underlying must be connected to low pressure areas (maximum two or three bars for pumps and 10-15 bars for engines).

The highest pressure to be supported by the sealing ring for an engine, relative to the sealing ring for a motor pump, is due only to the use of a steel washer especially profile that supports the sealing lip.

It has been shown in this way that the invention achieve the objective and the intended objects.

The invention conceived in this way is susceptible of numerous modifications and variations, all of them being within the scope of the appended claims.

All details can also be replaced with others technically equivalent.

In practice, the materials used as well as the shapes and dimensions can be any according to the requirements without abandoning the scope of protection of appended claims.

This request claims priority of Information of Italian Patent Application Nº. BO2002A000382.

Where the technical elements mentioned in any claims are followed by reference signs those reference signs have been included for the sole purpose of increase the intelligibility of the claims and so accordingly, such reference signs have no limiting effect on the scope of each element identified by example by Such reference signs.

Claims (19)

1. Separable heads for motors and hydraulic pumps of the type comprising a body (4), containing an overhanging shaft (7) and a shaft (10) disposed within said body, said shafts being mutually engaged by gears (8, 9 ), a cover (2) and a base (3); an open cavity (6) for the projecting shaft being provided in said base (3), and oil drainage means (26) being present in said cover (2), characterized by the fact that on the faces of the base ( 3) and of the cover (2) which are directed towards the body (4) respective networks of interconnected grooves (22) being provided that are adapted to accommodate respective deformable joints (23) made of a material such as rubber, and by the fact that said network of grooves (22) of the base (3) and of the covers (2) comprises cavities for rotationally supporting said shafts (17, 19, 20), which extend with peripheral holes facing, a groove that it is external to the cavities and is substantially formed with the figure of an eight with two mutually separate connecting portions, and a diamond-shaped perimeter groove with rounded corners that is connected to the groove in figure eight by short portions. 2. The heads according to claim 1, characterized in that said cover (2) has two blind cavities (19, 20), which are adapted to rotatably accommodate the ends of the inner shaft (10) and the protruding shaft (7 ), and due to the fact that said base (3) has a blind cavity (17) to accommodate the other end of the internal axis (10) and an open cavity (6) to accommodate the projecting axis (7), said internal axis (10) and said projecting shaft (7) being parallel and having respective engaged gears (9, 8) that are adapted there. 3. The heads according to claim 1, characterized in that said blind cavities (19, 20) are deeper than the grooves that constitute said net (22). 4. The heads according to claim 1, characterized in that said net (22) is symmetrical with respect to a plane passing through the axes of rotation of the two axes (7, 10) and with respect to a plane which It is perpendicular to the preceding plane and is equidistant from the axes of the two axes (7, 10). 5. The heads according to claim 4, characterized in that said joint is substantially formed as said network of grooves (22) and hermetically separates the high pressure portion of the low pressure portion of the hydraulic pump and motor. 6. The heads according to claim 1, characterized in that said open cavity (6) of the base has a portion (14) with a larger diameter in the region that is directed outward, when mounted, and another portion (13) having a diameter that is substantially equal to the diameter of said protruding shaft. 7. The heads according to claim 6, characterized in that at least one bushing and a sealing ring (15) adapted to prevent oil leakage are coupled in said portion (14) having a diameter greater than the open cavity ( 6) of the base (3). 8. The heads according to claim 7, characterized in that said sealing ring (15) adapted to prevent oil leakage is associated with a second high pressure sealing ring applied to engines. The heads according to claim 2, characterized in that said cover cavities are mutually connected by means of a connector conduit (21). 10. The heads according to claim 9, characterized in that said conduit (21) is obtained by providing a hole at the bottom of said cavities (19, 20) in the region where said grooves are closest, with a direction that is inclined outward and converges towards the center of said cover (2). 11. The heads according to claim 1, characterized in that said cover (2) has a rectangular profile and is symmetrical with respect to both central planes. 12. The heads according to claim 11, characterized in that two complementary cavities (24, 25) are provided along the plane of symmetry of the long side of said rectangular profile and are symmetrical with respect to the other plane of symmetry. 13. The heads according to claim 12, characterized in that said complementary cavities (24, 25) are formed as a circular sector with an obtuse central angle. 14. The heads according to claims 2, 7, 8 and 10, characterized in that said oil drainage means (26) are constituted by an opening (26), which connects one of said two complementary cavities (24) at the bottom of said conduit (21) for connecting said cavities (19, 20), said opening (26) being adapted to have oil flowing through it, said oil draining into the pump and the motor. 15. The heads according to claim 12, characterized in that said opening (26) is threaded and adapted to accommodate a plug. 16. The heads according to claims 1, 2 and 7, characterized in that said oil drainage means are constituted by a channel (28) in the outer wall of said lid (2), which interferes with one of said cavities (19, 20) and is a passageway, adapted to drain the oil externally, in one of its portions. 17. The heads according to claim 15, characterized in that said channel is threaded and is adapted to accommodate a threaded plug (29) with an O-ring to close said drain. 18. The heads according to claim 2, characterized in that said internal shaft (9) is hollow (18) and connects the respective cavities of the cover (2) and the base (3). 19. The heads according to claim 18, characterized in that said blind cavity (17) of the base (3) is reached by a passage (16) for the oil arriving from said portion of larger diameter (14) of the open cavity (16) of the base (3), to which at least one bushing and at least one sealing ring (15), adapted to prevent oil leaks, are coupled.