WO2015076716A1

WO2015076716A1 - Pump/motor

Info

Publication number: WO2015076716A1
Application number: PCT/SE2014/000134
Authority: WO
Inventors: Roger Gustavsson
Original assignee: Thordab Ab
Priority date: 2013-11-25
Filing date: 2014-11-17
Publication date: 2015-05-28
Also published as: SE1300726A1; SE540991C2

Abstract

Pump/motor (1) comprised of at least one housing, block (3) or the like comprised of at least three cylinder/piston units (7), each comprised of at least one cylinder (8) and at least one piston (9) connected to the at least one cam roller (12), which are driven by pressurized medium and pressurize medium. The pump/motor (1) is comprised of at least one unit (10) for converting rotational movement in a unit such as an axle to a reciprocating movement of the pistons (9) in the cylinders (8) alternatively converting the pistons' (9) reciprocating movement in the cylinders (8) to a rotational movement of the unit. The unit (10) is comprised of at least one first cam profile (11) and at least one second cam profile (13) whose cams profiles face each other at a distance from each other forming an intermediate space in which at least one first cam roller (12) that lies against and runs against the first cam profile (11), and at least one second cam roller (12) which lies against and runs against the second cam profile (13).

Description

Pump/Motor

Field of the Invention

The present invention concerns a variant of a pump/motor in accordance with the claims.

Background of the Invention Over time, many different types of motors and pumps have been developed. One variant of the above mentioned motors and pumps consist of motors/pumps which either are driven by pressurized fluid (liquid) or pressurize fluid. One type of these motors/pumps consists of hydraulic motors/hydraulic pumps.

One problem with existing types of pumps and motors such as hydraulic pumps and hydraulic motors, is that they mainly have fixed displacement and that they are designed to operate within relatively limited rpm ranges. If a need arises for a pump/motor with another displacement, the pump/motor must be replaced or be connected with at least a second pump/motor which entails expensive and cumbersome arrangements which usually require large spaces and are time-consuming. Furthermore, known hydraulic pumps/hydraulic motors with cam profiles (cam ring motors) are essentially only of low rpm types. This is due to several different reasons. One of these reasons is that the cam rollers' rpm is likely to be very high, which may cause problems for the cam rollers' bearings. A further problem with low rpm hydraulic motors of the cam ring type is that they require transmissions (gearboxes) and the like if a relatively higher rpm is desired. There are no previously known designs of hydraulic motors/hydraulic pumps which include an integrated transmission function that is not to a greater degree essentially ungainly or the like. Said ungainliness is for example caused by the motor/pump not including design solutions with dual-acting piston/cylinder units.

A further problem with existing pumps, such as hydraulic pumps, is that hydraulic pumps are not adapted to be operated at one point in time with a relatively lower rotational speed and at another point in time be operated with a relatively higher rotational speed. Said problems are particularly palpable when the available drive source has a substantially high rotational speed and also a low speed. In order to satisfy both of these needs with current known technology several different models (variants) of pumps/motors are needed. The costs of manufacturing and stocking these possible variants may thus be high. Another problem with known designs of hydraulic motors/hydraulic pumps is that they during manufacture usually require close tolerances and high accuracy. This is the case during the working of cam profiles and the like. Tolerance requirements imply relatively high manufacturing costs for components included in existing motors/pumps. A further problem with existing designs of hydraulic motors/hydraulic pumps is that the surface pressure on the cam rollers must not exceed a certain level, value. This means that hydraulic motors initially preferably may only have a limited operating pressure of the oil. None of the known designs of hydraulic pumps/ hydraulic motors includes a function by which the surface pressure between the cam rollers and cam profiles may be reliably controlled.

A further problem with existing types of hydraulic motors/hydraulic pumps is that they usually only include hydraulic cylinders (cylinder piston units) which are single-acting. This means that the known designs of hydraulic motors/hydraulic pumps, when compared to the design in accordance with the present patent application, will be relatively larger and bulkier. Designs to reduce the size of the pump/motor have been developed which use dual cam profiles. The big problem with known designs of pumps/motors with dual cams is that they require a rotational change of the cam rollers when a change to the drive of the cam rollers from the external cam profile to the internal cam profile and vice versa occurs. This design may also cause the distance between the cam profiles to be greater than the diameter of the cam rollers in order to function, which in turn leads to a gap arising between the cam rollers and cam profiles. The required clearance and rotational direction changes result in greater wear.

Prior Art

Over time, a large number of hydraulic motors/hydraulic pumps have been developed. One example of these is a hydraulic motor which includes double-acting cylinders, disclosed in US8252401. The design in accordance with US8252401 differs in other ways in relation to the design in accordance with the present patent application. For example, the design in accordance with US 8252401 does not include a replaceable unit with which the motor's characteristics may be changed.

In SE332399 is described a variant of a hydraulic motor/hydraulic pump which in the radial direction includes one first cam profile and at least one second cam profile (at a distance from each other in the radial direction). The design according to SE332399 further includes double- acting cylinder/piston units. A number of cam rollers connected to the piston/cylinder units runs alternately against the one cam profile and alternately against the other. For its operation the design requires that there is a gap between each respective cam roller and the cam profile that each respective cam roller lies against. The design also requires that the cam rollers change direction when they change contact between the inner cam profile and the outer cam profile and change contact between the outer cam profile to the inner cam profile. The design according to SE332399 does not therefore comprise the characteristics of the design according to the present application that includes at least one first support roller which lies against and runs along the first cam profile and at least one second support roller which lies against and runs along the second cam profile (without changing the direction of rotation and cam profile).

The above mentioned design according to SE332399 causes problems with relatively high wear on the cam rollers and cam profiles. The level of the problems of the design is of such a nature that the motor according to its description is not commercially viable. The design according to SE332399 also differs technically to a substantial extent from the design in accordance with the present patent application. The design's cylinders/piston units are for example not comprised of modules. Further, the design does not include an integrated transmission function which in turn inhibits the design from being able to be driven or operated with a relatively high or relatively low rpm.

Purpose of the Invention

The main purpose of the present invention is to create an improved motor/pump which solves or reduces at least one of the above, or later, mentioned problems. The purpose is achieved by a hydraulic motor/hydraulic pump in accordance with the claims. Brief Description of the Drawings

The invention will be described in the following detailed description with reference to the accompanying schematic drawings which in an exemplifying manner show the current preferred embodiments of the invention.

Fig. 1 A and IB show exemplifying embodiments of the present hydraulic pump/hydraulic with an axle in its center and without an axle in its center. Fig. 2A to 2G show a first embodiment of the present hydraulic motor.

Fig. 3 A and 3B show an exemplifying embodiment of the center section, the exchangeable unit.

Fig. 4 shows an exemplifying block with accompanying cylinder pistons. Fig. 5A to 5C show an exemplifying embodiment of a cylinder/piston unit with

accompanying components.

Fig. 6 shows an exemplifying hydraulic scheme over the control system of the dual-acting cylinder.

Fig. 7A and 7B show an alternative embodiment of the center section, the exchangeable unit, which includes at least one cam profile and at least one eccentric which may be mutually locked to and unlocked from each other.

Fig. 8A to 8E show in principle an alternative design solution which achieves a pump/motor 1 with a transmission function.

Fig. 9A and 9B show an alternative variant of a locking function between the eccentric and the ring-shaped section.

Fig. 10A and 10B show an alternate embodiment of the present motor/pump.

Fig. 11 A and 1 IB show alternate embodiments of the design with an attached transmission.

Detailed Description of the Invention

With reference to the figures is shown a pump 1, or alternatively a motor 1 in accordance with the present patent application. The pump (motor) 1 is comprised of at least one housing, block 2 or the like and at least one unit 3 which transmits rotational movement (rotary motion) to or from the pump/motor. The unit 3 for transferring rotational movement to or from the pump/motor 1 consists of, in the exemplifying embodiment an axle 4. When the design works as a pump, the axle 4 constitutes an input axle and when the design works as a motor, the axle 4 constitutes an output axle. The unit for transmitting rotational movement to or from the pump/motor may in alternative embodiments be comprised of the house, the block 2 or the like. The pump/motor 1 may also include a second unit for transmitting rotational movement to and from the pump/motor. When used as a pump the design is intended to pump some type of fluid such as hydraulic oil, water or other types of fluids which the pump is able to pump. It is further conceivable that the pump pressurizes gas or gases. When used as a motor the design may be driven by some type of fluid such as hydraulic oil, water or other fluids with which the motor may be driven. It is also conceivable that the motor is driven with pressurized gas or pressurized gases.

In the exemplifying embodiments, the housing is preferably comprised of or includes at least one block and at least one gable end 5 and in the exemplifying embodiment of at least one first gable end 5 and at least one second gable end 6. In alternative embodiments, at least one gable end 5 or 6, or the gable ends 5 and 6, may be integrated in the housing, block 2 or the like.

The design preferably includes several cylinder/piston units 7 each which include at least one cylinder (cylinder unit) 8 and at least one piston 9 (shown for example in Fig. 2 and in Fig. 5B and 5C). In alternative embodiments, the number of cylinder/piston units are at least three. In further alternative embodiments, the number of cylinder/piston units may be fewer than three. A specific feature of the present invention is that the pump's/motor's characteristics may be changed so that it may either be driven or be the driver, with at least one relatively lower rotational speed and at least one relatively higher rotational speed (relatively lower gear ratio and a relatively higher gear ratio). These different characteristics are achieved in some of the embodiments by the unit 10, that transforms rotational movement into a reciprocating movement of the piston 9 in the cylinder 8, that is exchangeable (such as a replaceable, interchangeable module). In other embodiments, this function is achieved by an integrated (or arrangement connected to the block) transmission function (transmission device).

With reference to Fig. 2A - 2G, a first principal embodiment (configuration) of the pump/motor 1 is shown. In the first embodiment, the conversion of rotational movement to the pistons' 9 reciprocating movement in the cylinders 8 is achieved by at least one first cam profile 11. The unit 10 therefore includes at least one first cam profile 11 which via cam rollers 12, support rollers or similar control the pistons' 9 reciprocating movement in the cylinders 8.

In one preferred embodiment, the design is comprised of at least one first inner cam profile 11 and at least one outer cam profile 13 which via the cam rollers 12, or the like, control the pistons' 9 reciprocating movement in the cylinders 8. In Fig. 2D is shown an embodiment which includes at least one first inner (in the radial direction) cam profile 11 and at least one first outer (in the radial direction) cam profile 13 and, further, at least one second inner cam profile 14 and at least one second outer cam profile 15. The unit 10 in alternative

embodiments is comprised of an exchangeable module. Referring to Figure 2G, it is shown how at least one of the cam profiles in alternative embodiments may be composed of segments 16 which when compounded (combined) forms (builds up, creates) the cam profile. The advantage of the cam profile being compounded by segments is that it facilitates manufacture, and preferably also reduces the amount of material needed in its manufacture. Referring to Fig. 3 A and 3B, a second principal embodiment of the pump/motor 1 is shown where it is intended to be driven by a drive unit with a relatively higher rpm, or drive a unit with a relatively higher rpm than the unit according to the embodiments in accordance with Fig. 2 A to 2C. In the shown embodiment in Fig. 3 A and 3B of the unit 10, the unit 10 includes at least one eccentric 17 which, via at least one transmission device 18, transfers the eccentric's 17 movement in the radial direction to the piston 9 or the pistons 9. The unit 10 in alternative embodiments is comprised of an exchangeable module.

During rotation of the axle 4 with the accompanying eccentric 17, or alternatively the connected eccentric 17, the pistons 9 perform a reciprocating movement in the cylinders 8. The eccentric 17 in the exchangeable unit 10 may have different shapes where, for example its eccentricity may vary between different embodiments of the motor. The eccentric 17 may in alternative embodiments be interchangeable with respect to the axle.

In the exemplifying embodiment of the pump/motor shown in Fig. 3A and 3B, the pump/motor 1 is comprised of at least one transmission device 18 which transfers the eccentric's rotational movement into the reciprocating movement of the pistons in the cylinders or transfers the pistons' reciprocating movement to the eccentric's rotational movement. The transmission device 18 includes, in the exemplifying embodiment, which does not limit the scope of the invention, at least one completely or partially ring-shaped section 19. The ring-shaped section 19 preferably includes a hole, preferably circular, in its center (why this part is called ring-shaped is because the exterior may have another shape than ring-shaped). The edge of the circular hole is affected by the eccentric's eccentric part. During the rotation of the axle with its associated eccentric, the eccentric induces the ring-shaped section to change positions in the radial direction that corresponds to the eccentric's eccentrical form.

The transmission device 18 of the design shown in Fig. 3 A and 3B include push rods 20 which are connected to the ring-shaped sections radial outer section. The push rods 20 or the like are in their one end articularly arranged via connection elements 21 to the ring-shaped section 19. The push rods 20 are in their other end preferably articularly connected to the axle 22, to which the cam rollers 13 are connected, the cam rollers are affected by, or affect, one or more cam profiles.

During a rotation of the axle 4 with the accompanying eccentric 17, the pistons 9 are induced by the push rods 20 to perform a reciprocating movement in the cylinders 8. The ring-shaped section's outer diameter may vary within the scope of the invention. The ring-shaped section may be of another shape than ring-shaped that is suitable for the purpose.

Referring to Fig. 4A, an exemplifying embodiment of the block 2 with the accompanying cylinder/piston units 7 is shown. The block according to the embodiment includes at least three cylinder/piston units 7 and preferably a plurality of cylinder/piston units 7. One exemplifying embodiment of the cylinder/piston units 7 is shown in more detail in Fig. 5 and described more fully in the accompanying description. When in operation the block 2 is preferably stationary. In alternative embodiments it is conceivable that the block 2 rotates and that the center section (the exchangeable part, the module) 10 is stationary. In further alternative embodiments of the pump/motor is conceivable that both the center section (the exchangeable part, the module) 10 and the block 2 rotate. In the exemplifying embodiment, the block 2 includes channels for the supply of liquid/liquids or gas/gases and connections for suction lines and return lines, and further for those skilled in the art obvious design details.

With reference to Fig. 5 A to 5 C, an exemplifying embodiment of the cylinder/piston unit 7 with associated components is shown. The cylinder/piston unit 7, in the exemplifying embodiment, includes at least one piston 9 that is connected to a piston rod 23, at least one cylinder housing 24 and at least one axle 25 to which the piston 9 via the piston rod 23 is connected. The cylinder/piston unit 7, in the exemplifying embodiment, includes at least one guide 26 for control of the axle 25 and the cam roll's (cam rollers') 12 movement in the cylinders' 8 axial direction. The exemplifying cylinder/piston unit's 7 design does not limit the inventive scope of the present pump's/motor's 1 design. Referring to Fig. 5B, a cross-section of cylinder/piston unit 7 in its axial direction is shown. In Fig. 5B, the axle 25 and its accompanying bearings are shown. Fig. 5B also shows how the cylinder/piston unit 7 preferably includes at least one replaceable liner 27. By replacing the liner 27 and the piston 9, the cylinder/piston unit's 7 displacement may be altered. The displacement may be varied by altering the cylinder's and piston's diameters, such as by reducing or increasing them.

In Fig. 5B and in Fig. 5C, is shown that at least one first cam roller (wheel) 12 is connected to the axle 25, said cam roller is intended to run against at least one first cam profile. The design also preferably includes at least one second cam roller (wheel) 12 which is intended to run along (lie against) at least one second cam profile (opposite at a distance placed cam profile).

In the exemplifying embodiment, the design includes at least one first cam roller (support roller) 12 which is intended to run against (along) at least one first inner cam profile and at least one second cam roller (support roller) 12 which is intended to run against (along) at least one second cam profile, at least one third cam roller (support roller) 12 intended to run against (along) at least one third cam profile 14 and at least one fourth cam roller (support roller) intended to run against (along) at least one fourth cam profile 15. The cam rollers 12 and the cam profiles (cam rings) may be conical in relation to cam rollers' axis of rotation and the cam profiles' center axis. The conical cam rollers are intended to bear against the cam profiles which are angled. The conical rollers' angle and the cam profiles' angles are preferably adapted to each other so that they obtain an acceptable function.

Fig. 5B and 5C also show that the piston rod is articular to the axle via at least one spherical roller bearing 28. The figures also show bearing 29, such as preferably roller bearings, which articulates the axle 25 relative to the guides 26. The design makes it possible for eventual bending of the piston rod to be fully or partially reduced. The design with spherical bearing allows the axle to be tilted (misaligned) allowing for greater tolerances than existing types of pumps/motors. This is made possible by the axle being articulated relative to the piston rod with at least one spherical bearing or other for the purpose suitable means of articulation which permits misalignment.

By way of the design, movement of the piston is controlled in the one radial direction by the cam profiles 11 and 14. In the opposite radial direction, the piston's movement is controlled by cam profiles 13 and 15. Fig. 5B shows a cylinder 8 with its associated piston 9. The piston 9 separates the cylinder 8 into at least one first chamber (A side) 30 and at least one second chamber 31, whose pressurization is controlled by at least one control system. The figure also shows seals connected to the liner. In the exemplifying embodiment, the design includes at least one cavity (chamber) 32 which may take up leakage of pressurized medium. The cavity 32 communicates with the low pressure side (feed).

A characterizing feature of the present pump's/motor's design is that it includes a function with which the force which affects the piston's cam rollers, may be controlled. By control of this force, it is possible to regulate the surface pressure between the cam rollers and the cam profiles.

Referring to Fig. 6, an exemplifying embodiment is shown in a hydraulic scheme of a subsystem of the hydraulic system with which a control of the force affecting the cam rollers may be accomplished (with which a regulation of the surface pressure between the cam rollers and cam profiles may occur). With this design, it is also possible to control the pump's displacement. The figure shows a cylinder 8 with its associated piston 9. The piston 9 separates the cylinder 8 into at least one first chamber (A side) 30 and at least one second chamber (B side) 31. The design further includes at least one valve 33 which controls the flow to the chamber 30 (A side) and at least one valve 34 which controls the inflow to chamber 31 (B side). The design includes a valve 35 that opens and closes at least one channel connecting chambers 30 (A side) and chambers 31 (B side). By activating the valves 33-35 in different ways, at least three different maximum pressures between the cam roller and the cam profile is achieved (besides the off position). By controlling of the respective valve to open or close, an adaptation of pressure and flow occurs.

1. When valve 33 on the A side is activated, the volume in chamber 30 (A side) is used in the cylinder.

2. When valve 34 is activated, the volume in chamber 31 (B side) is used in the cylinder.

3. When valves 33, 34 and 35 are activated, the volume that constitutes the difference between chambers 30 (A side) in the cylinder and chamber 31 (B side) in the cylinder is used, which corresponds to the piston rod's volume in the cylinder. At low output oil pressure, the above options 1 to 3 may be used. At medium pressure, options 2 and 3 are used. At high pressure, option 3 is used. When the pressure has risen to the maximum level, valves A and B open, which means that the cylinder does not press anything out of the cylinder's high-pressure side. Thus the pump does not pump the oil out to the high pressure side, instead the oil returns to the tank (low pressure side).

By way of this design, the hydraulic pressure (the pressurized fluid's pressure) may vary without exceeding the maximum surface pressure (critical surface pressure) of the cam rollers surface.

In alternative embodiments, the design includes pressure sensor at the channels to the A side and B side. By processing data from the pressure sensors, the status of the cylinder may be analyzed as well as the output power and input power being able to be calculated and controlled. With this control, it is possible to control and determine the power available as such for example at the start of a wind turbine when it is desirable to pump with low pressure.

It is conceivable that the system described above may be used in motor applications if suitable valves are selected such as a "proportional valve" or by selecting any other valves suitable for this purpose.

Referring to Fig. 7A and 7B, it is shown how the motor/pump functions in an alternative embodiment where the transmission of torque takes place through at least one cam profile and/or at least one eccentric. The design allows for the pump/motor to achieve an integrated transmission function with at least one relatively higher gear and at least one relatively lower gear. The design allows for the motor/pump to either be used as a cam ring motor (pump) or eccentric motor (pump).

In the exemplifying embodiment, the center section (exchangeable module) 10 includes at least one axle 4 with an accompanying eccentric 17. The eccentric 17 in turn affects at least one transmission device 18, which in the exemplifying embodiment is comprised of an essentially ring-shaped section 19, which includes at least one cam profile. In the

exemplifying embodiment, the transmission device 18 includes at least one first inner cam profile 11 and at least one first outer cam profile 13. In alternative embodiments, the transmission device 18 may include multiple cam profiles such as at least one first inner cam profile 11, at least one second inner cam profile 14, at least one first outer cam profile 13 and at least one second outer cam profile 15. Between the inner cam profiles 11 and 14 and the outer cam profiles 13 and 15, a space is formed in which at least one first cam roller 12, at least one second cam roller 12, at least one third cam roller 12 and at least one fourth cam roller 12 run. The inner cam profiles 11 and 14 and the outer cam profiles 13 and 15 are placed at a mutual distance which allows for each respective cam roller 12 to bear against a cam profile (may be two or more), but be free toward the other cam profiles (the others may be two or more). The first cam roller runs against the first inner cam profile, the second cam roller runs against the first outer cam profile, the third cam roller runs against the second outer cam profile and the fourth cam roller runs against the second inner cam profile.

The ring-shaped section's (included in the transmission device) 19 inner diameter may vary within the scope of the invention. The design includes at least one device 36, function, with which the eccentric 17 and the transmission device 18 (the ring-shaped section) 19 may be locked and disengaged relative one another. In the exemplifying, but not limiting for the invention, embodiment of device 36, the device 36 consists of a locking device comprised of at least one first locking element 37 and one second locking element 38 which may be locked and disengaged from each other. In alternative embodiments, the locking device may consist of a different design than that which is shown. For example, it may consist of a coupling comprised of lamellae or other type of locking or coupling device.

When the transmission device 18, such as the ring-shaped section 19, and the eccentric 17 are locked in relation to each other, such as is exemplified in Fig. 7A, the ring-shaped section with cam profiles will rotate with the same speed as the eccentric and axle. The cam profiles will perform an eccentric motion which via the cam rollers is transmitted to the axial reciprocating movement of the pistons. In this embodiment, the pump/motor is especially suitable for applications with a relatively lower rpm on the input or output axle (depending on whether the device is used as a pump or motor). When the transmission device 18, such as the ring-shaped section 19, is disengaged from the eccentric 17, such as is shown in Fig. 7B, the transmission device 18 such as the ring-shaped section 19, will move only in a limited range (the transmission device's ring-shaped section does not rotate but performs a limited movement caused by the eccentric). When the axle rotates it induces the transmission device (the ring-shaped section) to move in the radial direction in a corresponding manner to the eccentric's shape. In the application where the ring-shaped section and the eccentric are disengaged from each other, the pump/motor is especially suitable for relatively higher rpm on the input or output axle (depending on whether the device is used as a pump or motor).

In alternate embodiments, the motor/pump includes least one position sensor or the like, which is intended to be used to measure (indicate) where each piston is in relation to the cylinder. In alternative embodiments, the position of the piston may be measured by another technology suitable for the purpose. The position sensor is used to measure the angle and rpm of the output or input axle.

With reference to Fig. 8A to 8E, an alternative principal design solution is shown to achieve a pump/motor 1 with a transmission function. In the exemplifying embodiment of the principal design solution of the pump/motor 1 , the pump/motor includes both a function as a cam ring motor (pump) and an eccentric motor (pump). In the embodiment shown the figures, the transmission device 18 (ring-shaped section) which includes the cam profiles, is provided with cogs 39. The transmission device 18 (ring-shaped section 19) forms in the embodiment a cog (gear) wheel with external cogs 39 which engage with the cogs 40 in the block (the housing) or the section connected to the block (which forms a gear wheel with internal gogs). The design according to the embodiment allows for the motor/pump to include at least one first output/input axle 4 and at least one second output/input axle 41. The first output/input axle 4 is connected to the eccentric and the second output/input axle is connected to the transmission device (the section with the cam profiles) 41. The second output axle 41 is connected to the section (transmission device) with the cam profiles so that the eccentric movements in the transmission device (the section with the cam profiles) are limited and essentially are not transmitted to the second output axle 41. This may for example be accomplished by a coupling comprised of pegs and holes with larger dimensions than the pegs (pegs and holes are not shown in the figures). The figures show two of the cylinder piston units' 7 piston rods 23 exposed (without cylinders and pistons) with the intention to make clear the embodiment's other components.

This design solution achieves (creates) an exchange between two of the motor's/pump's rotating parts. The gear ratio is dependent upon the relative difference in cogs between the gear wheel with external cogs 39 and the gear wheel with internal cogs 40. For example, the gear ratio may be 10 to 1 that is to say when the eccentric rotates ten turns, the section with the outer cam profiles rotates one turn. In alternative embodiments, the gear ratio may be greater or less than 1 to 10 or 10 to 1. Fig. 8E shows in a cross-section how each cam roller lies against the each respective cam profile. The first cam roller bears against the first cam profile, the second cam roller bears against the second cam profile, the third cam roller bears against the third cam profile and the fourth cam roller bears against the fourth cam profile. Each respective cam roller rests and runs against one cam profile. This design achieves the function of dual-acting cylinder piston units which may be used against the inner and outer cam profiles (alternatively cam profiles which are spaced from each other in the axial direction as shown in Fig. 10A and 10B) without the cam rollers needing to change their rotational direction as in the prior art described in SE332399. Referring to Fig. 9A and 9B, an embodiment of the pump/motor is shown including an alternative technical solution for how the cam profile fitted transmission device's 18 (ring- shaped section 19) movement relative to the block 2 may be controlled (restricted). In the exemplifying embodiment, this is accomplished by at least two, preferably opposing cam rollers connected to each respective piston in the cylinder piston unit (not shown in figures), their mutual positions controlled in relation to the cam profiles so that the cam profiles are completely or partially prevented from rotating relative to the cam rollers 12.

The design solution (the principal design) assumes that the motor/pump includes or is connected to at least one control system. In this embodiment, the eccentric 17 will rotate relative to the ring-shaped section. Referring to Fig. 10A and 10B, an alternative embodiment of the present motor/pump 1 is shown where each respective cylinder/piston unit's 7, cylinder 8 and piston rod 23 in their axial directions are directed in the motor's/ pump's 1 axial direction unlike the previously disclosed embodiments of the motors/pumps 1 where the cylinders 8 and the piston rods 23 in the axial direction are directed in each respective pump's/motor's radial direction. The design according to the embodiment of Fig. 10A and 10B include at least one first can profile 11 and at least one second cam profile 13, placed at a mutual distance from each other in the pump's/ motor's 1 axial direction. The cylinder/piston units' 7 support rollers 12 are placed between the cam profiles.

Fig. 10A and 10B show an exemplifying embodiment that includes a motor/pump 1 with at least one first cam profile 11, one second cam profile 13, one third cam profile 14 and one fourth cam profile 15. The design includes a number of cylinder/piston units 7. Against the first cam profile 11 runs a first cam roller 12, against the second cam profile 13 runs a second cam roller 12, against the third cam profile 14 runs at least one third cam roller 12 and against the fourth cam profile 14 runs at least a fourth cam roller 12.

In alternative embodiments, however, the number of cam profiles and cam rolls may be more or less than four and/or the number of cam rollers may be more or less than four. The design in accordance with the embodiment has great advantages. The design has for example the advantage that it allows the cam profiles and cam rollers in the motor/pump to both constitute force transmitting units (motor/pump) and bearings (supports) in the axial direction. This design may, for example be unexpectedly used as a motor and bearing in so- called reversible ring bearings. The design represents both drive and bearings which are integrated in one unit which may for example allow for a more compact design than previously known designs. Further, this design allows for reversible ring bearings to become substantially cheaper to produce than previously known designs.

Referring to Fig. 11 A, it is shown how the transmission function for the pump/motor 1 may be achieved by a gear, gearbox 42 or the like connected to, or integrated with, the

pump/motor l .

Fig. 1 IB and 11C show how the present pump/motor 1 includes or is connected to (at) at least one electric motor/generator 43 and at least one gear (gearbox) 42. In this case the gear function is achieved by at least one gear (alternatively gearbox or like) and the pump/motor 1 being integrated into one unit. The pump/motor and generator/pump may be driven by or drive individually or in combination. The design includes the necessary couplings or the like with which the pump/motor and generator/pump may be driven by or drive individually or in combination with each other.

The pump/motor 1 may be comprised of or include some technology from one or more of the previously described embodiments of the pump/motor 1. The pump/motor 1 preferably includes in the preferred embodiment, at least one first cam profile 1 1 , at least one second cam profile 13, at least one third cam profile 14 and a fourth cam profile 15. Against the first cam profile 1 1 runs one first cam roller 12, against the second cam profile 13 runs one second cam roller, against the third cam profile 14 runs at least one third cam roller 12 and against the fourth cam profile 15 runs at least one fourth cam roller 12. In alternative embodiments, however, the number of cam profiles and cam rolls may be more or less than four and/or the number of cam rollers may be more or less than four. In the detailed description of the present invention, design details and technology may be omitted that are apparent to persons skilled in the art encompassed by the invention. Such obvious design details are included to the extent necessary for a proper function of the present pump/motor to be obtained. For example, the design includes hydraulic fittings and hydraulic hoses to the extent necessary for a proper function to be achieved. Furthermore, use of the invention requires requisite control systems to control the pump's/ motor's functions.

Even if certain preferred embodiments have been shown in more detail, variations and modifications of the pump/motor may become apparent to those skilled in the field of the invention. Thus it is possible to combine embodiments where feasible. All such modifications and variations are regarded as falling within the scope of the following claims.

It is conceivable that the present invention may be defined as a method for controlling the surface pressure between at least one cam roller and at least one cam profile in accordance with Fig. 6 with the associated description on page 8.

In alternative embodiments it is conceivable that one of the cylinder's chamber is designed to pump air (compress air, or gas, or gases) and the other of the cylinder's chambers may be used for pumping water or other liquids.

By way of the design, a pump that pumps air and a pump for water or fluid may be integrated in one and the same motor. The pumping of air produces a lot of heat which may be carried off by the water. A hybrid pump that sucks a little water on the low pressure side becomes a large flow of air-water mixture on the high pressure side.

Advantages of the Invention

A number of advantages are achieved with the present invention. The most obvious is that a hydraulic motor/hydraulic pump is achieved with which at least one of the aforementioned problems are eliminated or reduced.

Claims

1. Pump/motor (1) comprised of at least one housing, block (3) or the like which is comprised of at least three cylinder/piston units (7), each comprised of at least one cylinder (8) and at least one piston (9) connected to the at least one cam roller (12), which are either driven by pressurized medium or pressurize medium, and that the pump/motor includes at least one transmission device (18) for converting rotational movement in a unit (3), which transmits rotational movement to or from the pump/motor, such as an axle (4), to a reciprocating movement of pistons (9) in the cylinders (8) alternatively converting the piston's (9) reciprocating movement in the cylinders (8) to a rotational movement in the axle (4) characterized in that the cylinder piston units (7) are dual-acting and that the transmission device (18) includes at least one first cam profile (11) and at least one second cam profile (13) whose cam profiles face each other at a distance from each other forming an intermediate space in which at least one first cam roller (support roller) (12), which lies against and runs against the first cam profile (11), and at least one second cam roller (support roller) (12) which lies against and runs against the second cam profile (13) and that the pump/motor (1) includes a gear function with at least one relatively higher ratio and one relatively lower ratio.

2. Pump/motor (1) in accordance with claim 1 characterized in that the pistons (9) and the cylinders (8) in the axial direction are directed in the motors radial direction that is to say constituted by a radial piston machine.

3. Pump/motor (1) according to at least one of claims 1 and 2 characterized in that the pump/motor is comprised of at least one first cam profile and at least one second cam profile, which controls the pistons' (9) movement in the one radial direction and that the pump/motor is comprised of at least one third cam profile (13) which controls the pistons' (9) movement in the opposite radial direction.

4. Pump/motor (1) according to at least one of claims 3 or 4 characterized in that the motor is comprised of at least one first cam profile (11) and at least one second cam profile (14) which controls the pistons' movement in the one radial direction and that the pump/motor is comprised of at least one third cam profile (13) and at least one fourth cam profile (14) which control the pistons' movement in the opposite radial direction.

5. Pump/motor (1) in accordance with claim 1 characterized in that the pistons and cylinders are directed in the motor's axial direction.

6. Pump/motor (1) in accordance with claim 1 characterized in that the unit (10) is comprised of at least one first cam profile (11) and at least one second cam profile (14) and one first opposing cam profile (13) and at least one second opposing cam profile (15) and that at least one first cam roller (12) runs against the first cam profile (1 1) and at least one second cam roller (12) runs against the second cam profile (14) and that at least one third cam roller (12) runs against the first opposing cam profile (13) and at least one fourth cam roller (12) runs against the second opposing cam profile (15).

7. Pump/motor (1) according to at least one of the previous claims characterized in that each cylinder/piston unit (3) is comprised of at least one cylinder unit (8) and at least one piston (9), whose piston (9) is connected to, or integrated with a piston rod (23), whose piston rod (23) is articularly arranged to at least one axle to which at least one first cam roller (12) and at least one second cam roller (12), at least one third cam roller (12) and at least one fourth cam roller (12) is rotatably connected.

8. Pump/motor (1) according to one of the previous claims characterized in that at least one first cam roller (12) and at least one second cam roller (12) are conical and that the cam profiles against which the conical cam rollers run against is angled relative to and adapted after the conical cam rollers.

9. Pump/motor (1) according to at least one of the previous claims characterized in that the pump/motor gear function is achieved by the pump/motor including a transmission device (18) which includes a ring-shaped section that includes cam profiles, which include a center hole with an eccentric, and that the eccentric and the ring-shaped section may be locked or unlocked relative each other and that the axle's position in the pump's/motor's radial direction is affected by at least one eccentric which affects the cam profiles' position in the radial direction.

10. Pump/motor (1) according to at least one of the previous claims characterized in that the design includes at least one device, system or subsystem to control the surface pressure between at least one cam roller and at least one cam profile.

11. Pump/motor (1) according to at least one of the previous claims characterized in that the cylinder units' first chamber (30), A-chamber, and second chamber, B-chamber (31), are connected together via at least one channel, said channel being provided with at least one valve (35) which opens or closes the channel between the first chamber

(30) and the second chamber (31).

12. Pump/motor (1) according to at least one of the previous claims characterized in that the cylinder units' first chamber (30), A-chamber, and second chamber, B-chamber

(31) , are connected together via at least one channel, said channel being provided with at least one valve (35) which opens or closes the channel between the first chamber (30) and the second chamber (31) and that the design includes at least one valve (33) which controls the flow into the first chamber (30) and at least one second valve (34) which controls the flow into the second chamber (31).

13. Pump/motor (1) according to at least one of the previous claims characterized in that the transmission device (18) and axle (4) are part of an exchangeable modular unit (10), for converting rotational movement to a reciprocating movement for the piston (9) in the cylinder (8), which is included in a module system comprised of at least one first module and at least one second module with different gear ratios.