JP2014129770A - Radial piston type hydraulic machine, method for assembling the same, and wind power generation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radial piston type hydraulic machine in which contact pressures generated at contact portions between a cam surface of a ring cam and rollers are low.SOLUTION: A radial piston type hydraulic machine 40 comprises: a plurality of pistons 44 arranged along radial directions of the hydraulic machine; a plurality of rollers rotatably provided to the pistons respectively; a cylinder block 48 provided with a plurality of cylinders for guiding the plurality of pistons respectively so as to allow reciprocation along the radial directions; and a ring cam 52 configured to contact the plurality of rollers, including a plurality of lobes 80a arranged along the circumferential direction of the hydraulic machine, opposed to the plurality of pistons, and configured rotatably so that the lobes move in the circumferential direction relatively with respect to the plurality of pistons. The ring cam is an annular body continuing in the circumferential direction, and its surface in contact with the rollers is a curved surface having no steps in the circumferential direction.

Description

  The present invention relates to a radial piston hydraulic machine that can be applied to a hydraulic pump, a hydraulic motor, or the like, an assembling method thereof, and a wind turbine generator equipped with the radial piston hydraulic machine.

  In recent years, power generation devices using natural energy such as sunlight and wind power have become widespread from the viewpoint of conservation of the global environment. For example, in a wind turbine generator, wind energy is converted into rotor rotational energy, and the rotor rotational energy is converted into electric power by a generator. Conventionally, in a wind turbine generator, since the rotational speed of the rotor is smaller than the rated rotational speed of the generator, a mechanical (gear type) speed increaser is provided between the rotor and the generator.

  On the other hand, for the purpose of improving the power generation efficiency, the wind power generator is being increased in size, and the weight and cost of the gearbox tend to increase. For this reason, wind power generators that employ a hydraulic transmission that combines a hydraulic pump and a hydraulic motor instead of a mechanical gearbox have attracted attention. Normally, this hydraulic transmission has a hydraulic pump driven by the rotation of the rotor, a hydraulic motor connected to the generator, and a pressure oil pipe for circulating the pressure hydraulic motor between the hydraulic pump and the hydraulic motor. ing. For example, Patent Document 1 discloses a wind turbine generator that transmits rotational energy of a rotor driven by wind power to a generator via a hydraulic transmission.

  On the other hand, a radial piston hydraulic machine in which a plurality of cylinders are arranged radially is known. For example, Patent Document 2 discloses a radial piston hydraulic pump used in a power transmission device. The hydraulic pump includes an outer race having a cam surface on an inner peripheral surface and an inner race having a plurality of cylinders arranged radially facing the outer race. The plurality of cylinders of the inner race have pistons that slide inside, and each piston is attached with a ball that comes into contact with the cam surface.

  Patent Document 3 discloses a radial piston hydraulic machine that functions as a drive train for a wind turbine generator. The radial piston hydraulic machine includes a piston that reciprocates in a cylinder, a roller attached to the piston, and a cam having a cam surface that comes into contact with the roller. Moreover, in the radial piston hydraulic machine of the wind power generator disclosed in Patent Document 4, a ring-shaped cam is mounted on the outer peripheral surface of the rotating shaft connected to the rotor. This ring cam is divided and formed in the circumferential direction and the axial direction, and is attached to the outer peripheral surface of the rotating shaft with bolts for each divided piece, and is arranged in a plurality of rows in the axial direction of the rotating shaft.

International Publication No. 2010/033035 JP 2010-19192 A US Patent Publication No. 2010/0040470 International Publication No. 2012/073280

  The rotor shaft of the wind power generator has a large diameter. Therefore, the rotary shaft of the radial piston hydraulic machine connected to the rotor shaft also has a large diameter, and the ring cam attached to the outer peripheral surface of the rotary shaft also becomes large and heavy. In addition, when the cylinders of the hydraulic machine are arranged in a plurality of rows in the axial direction of the rotary shaft, a phase difference is applied to the cam surface in the axial direction in order to equalize the discharge pressure oil of the hydraulic machine in time series. It was already made. Therefore, the shape of the ring cam is complicated.

  Therefore, as disclosed in Patent Document 4, from the viewpoint of workability at the time of manufacturing and assembling the ring cam, the ring cam is manufactured by being divided in the circumferential direction and the axial direction. However, in order to assemble the divided cam pieces, it is not only troublesome to assemble, but it is necessary to make bolt holes on the cam rolling surface. Further, a step is likely to occur between the cam pieces due to variations in processing of the cam pieces.

  In a radial piston type hydraulic machine, a roller is provided on a sliding piston in a cylinder, and when the roller is guided to a cam surface, the piston reciprocates to supply and discharge hydraulic fluid in a hydraulic chamber. Done. When a step is generated on the cam surface, the surface pressure on the roller is likely to stand at the step portion. Since hydraulic oil is an incompressible fluid, a large pressure is instantaneously applied to the cam surface, roller, and piston by this surface pressure. If this is continued, the ring cam and the roller may be worn and the life may be reduced.

  At least one embodiment of the present invention provides a radial piston hydraulic machine having a small surface pressure generated at a contact portion between a cam surface of a ring cam and a roller, and a wind turbine generator including the same, in view of the problems of the related art. With the goal.

  In order to achieve such an object, a radial piston hydraulic machine according to some embodiments of the present invention includes a plurality of pistons arranged along the radial direction of the hydraulic machine, and a plurality of pistons that are freely rotatable. A plurality of rollers provided, a cylinder block provided with a plurality of cylinders for respectively guiding a plurality of pistons so as to be capable of reciprocating along the radial direction of the hydraulic machine body, and a structure configured to contact the plurality of rollers And having a plurality of lobes arranged along the circumferential direction of the hydraulic machine and arranged to face the plurality of pistons so that the lobes move relative to the plurality of pistons in the circumferential direction of the hydraulic machine. And a ring cam configured to be rotatable. The ring cam is an annular body that is continuous in the circumferential direction of the hydraulic machine, and the contact surface with the roller is a stepless curved surface having no step in the circumferential direction of the hydraulic machine.

Some hydraulic machines have a rotating part inside the cylinder block and others have a rotating part outside the cylinder block. In the former, the ring cam is an outward ring cam with the cam surface facing outward, and in the latter, the ring cam is an inward ring cam with the cam surface facing inward. The present invention is applicable to both.
Also, the piston is arranged in the cylinder so as to reciprocate along the radial direction of the hydraulic machine, but the term “along” is strictly parallel in the geometric sense to the radial direction of the hydraulic machine. It does not indicate a state, but is used to include a state in which a certain angle (for example, an angle within 30 °) is formed in the radial direction of the hydraulic machine.

  The ring cam is an annular body that is continuous in the circumferential direction of the hydraulic machine, and the cam surface forms a stepless curved surface that has no step in the circumferential direction, so there is no increase in surface pressure due to the step on the cam surface. . For this reason, since a large surface pressure is not instantaneously generated on the cam surface or the roller, wear of the ring cam or roller and a decrease in the service life can be avoided.

  In some embodiments, the ring cam is attached to the rotating shaft by an interference fit. This facilitates mounting of the ring cam on the rotating shaft. In one embodiment, an anti-slip member for preventing relative slip in the circumferential direction of the ring cam with respect to the rotary shaft can be provided between the rotary shaft and the ring cam that is tightly fitted. As this anti-slip member, for example, a pin or a key can be used. Thereby, relative slip in the circumferential direction of the ring cam with respect to the rotating shaft can be prevented. Therefore, a larger torque can be transmitted between the rotating shaft and the ring cam.

  In one embodiment, the ring cam is fitted on the outer peripheral surface of the rotary shaft, and includes a plurality of annular segments with different inner diameters arranged in the axial direction of the hydraulic machine, and the plurality of annular segments are annular with the largest inner diameter. It arrange | positions so that an internal diameter may become small as it leaves | separates to the said axial direction from a segment. As a result, mounting of all the annular segments is facilitated by attaching them to the rotating shaft in order from the annular segments having the larger inner diameter. Further, the larger the axial length of the ring cam, the more difficult the interference fit. In particular, in the case of shrink fitting, it becomes difficult as the temperature decreases. In this embodiment, since the annular segments divided in the axial direction of the hydraulic machine are mounted one by one, the interference fit can be easily performed.

  In one embodiment, the ring cam is fitted on the inner peripheral surface of the rotating shaft, and includes a plurality of annular segments with different outer diameters arranged in the axial direction of the hydraulic machine, and the plurality of annular segments have an outer diameter. It arrange | positions so that an outer diameter may become large as it leaves | separates from the smallest annular segment to the said axial direction. As a result, the annular segments having the smaller outer diameter are sequentially attached to the rotating shaft, so that all the annular segments can be easily attached by interference fitting as in the above embodiment.

  In one embodiment, the ring cam is disposed adjacent to the input shaft or output shaft of the hydraulic machine in the axial direction of the hydraulic machine, and is directly connected to the input shaft or output shaft. Accordingly, it is possible to attach a ring cam in the axial direction to the end of the input shaft or output shaft of the hydraulic machine. Here, if the hydraulic machine is a hydraulic pump, the “input shaft” is a rotating shaft that gives a reciprocating motion to the piston of the hydraulic pump. The “output shaft” is a rotating shaft driven by a piston if the hydraulic machine is a hydraulic motor. For example, a hydraulic pump used in a wind power generator is a rotor shaft, and a ring cam can be directly attached to the end of the rotor shaft. Moreover, if it is the hydraulic pump used for the wind power generator, a ring cam can be directly attached to the edge part of the rotating shaft of a generator. Therefore, it is not necessary to provide a rotating shaft of the hydraulic machine separately from the ring cam, and the cost can be reduced.

  In some embodiments, the plurality of cylinders are distributed in the axial direction of the hydraulic machine, and the plurality of lobes are linear in the axial direction over the range of axial positions in which the plurality of cylinders are distributed. Extended. In this configuration, the ring cam can be easily processed at low cost, and it can be easily mounted on the rotating shaft by an interference fit.

  In one embodiment, in addition to the above-described configuration, a virtual cylinder row formed by m virtual cylinders (where m is an integer of 2 or more) arranged in the axial direction of the hydraulic machine is provided in the circumferential direction of the hydraulic machine. For a virtual array provided with n columns (where n is an integer of 2 or more), a plurality of cylinders are arranged according to an array in which the circumferential positions of m virtual cylinders belonging to each virtual cylinder column are different from each other. Located in the cylinder block.

  In the case of a hydraulic pump having a plurality of cylinder rows in the axial direction, it is desired to equalize the discharge of high-pressure oil in time series in order to suppress vibration and pulsating flow caused by the discharge of high-pressure oil. For this reason, it is conceivable to provide a phase difference in the shape of the cam surface for each cylinder row in the reciprocating motion of the piston. However, in this case, the shape of the cam surface becomes complicated, and the cam processing becomes cumbersome and expensive. Therefore, as described above, a plurality of cylinders are arranged in the cylinder block in accordance with an arrangement in which the circumferential positions of the m virtual cylinders belonging to each virtual cylinder row are made different from each other as described above. For example, the cylinder row is inclined at a certain angle with respect to the axial direction of the hydraulic machine. Thereby, equalization of high pressure oil can be achieved without providing a phase difference in the shape of the cam surface. Therefore, cam processing can be easily and cost-effectively.

  A method of assembling a radial piston hydraulic machine according to some embodiments of the present invention includes a plurality of pistons arranged along a radial direction of the hydraulic machine, and a plurality of pistons rotatably provided on each of the plurality of pistons. And a plurality of lobes arranged in contact with the plurality of rollers and arranged along the circumferential direction, and an annular body that is continuous in the circumferential direction of the hydraulic machine. A method of assembling a radial piston type hydraulic machine including a ring cam that is a stepless curved surface having no step in the circumferential direction and a rotating shaft to which the ring cam is attached, comprising a cam mounting step for attaching the ring cam to the rotating shaft by an interference fit Yes.

  This eliminates the need for forming a bolt hole for mounting over the entire circumference of the cam surface and eliminates a step on the cam surface, so that a surface pressure increase due to the step on the cam surface does not occur. For this reason, since a large surface pressure is not instantaneously generated on the cam surface or the roller, wear of the ring cam or roller and a decrease in the service life can be avoided.

  In one embodiment, the ring cam includes a plurality of annular segments having different inner diameters that are fitted on the outer peripheral surface of the rotating shaft, and the plurality of annular segments are separated from the annular segment having the largest inner diameter in the axial direction of the hydraulic machine. In the cam mounting step, an interference fit of the annular segment to the outer peripheral surface of the rotating shaft is performed in the order of moving away from the annular segment having the largest inner diameter in the axial direction. Thereby, as described above, it is possible to easily perform the interference fitting operation of each annular segment to the rotating shaft.

  In one embodiment, the ring cam includes a plurality of annular segments having different outer diameters that are fitted on the inner peripheral surface of the rotating shaft, and the plurality of annular segments are connected to the shaft of the hydraulic machine from the annular segment having the smallest outer diameter. It is arranged in the axial direction so that the outer diameter increases as it moves away from the direction, and in the cam mounting step, the annular segment is fastened to the inner peripheral surface of the rotating shaft in the order away from the annular segment having the smallest outer diameter. I do. Thereby, as described above, it is possible to easily perform the interference fitting operation of each annular segment to the rotating shaft.

  A wind turbine generator according to some embodiments of the present invention includes at least one blade, a hub to which at least one blade is attached, a hydraulic pump configured to be driven by rotation of the hub, and hydraulic pressure A wind power generator comprising a hydraulic motor configured to be driven by pressure oil generated by a pump and a generator driven by the hydraulic motor, wherein at least one of the hydraulic pump and the hydraulic motor is a radial piston The hydraulic machine includes a plurality of pistons arranged along a radial direction of the hydraulic machine, a plurality of rollers rotatably provided on each of the plurality of pistons, and a radial direction of the hydraulic machine. A cylinder block provided with a plurality of cylinders for respectively guiding a plurality of pistons so as to be capable of reciprocating along the cylinder, and a plurality of rollers. A plurality of lobes arranged in the circumferential direction of the hydraulic machine and arranged to face the plurality of pistons, and the lobes move relative to the plurality of pistons in the circumferential direction of the hydraulic machine. And a ring cam configured to be rotatable. The ring cam is an annular body continuous in the circumferential direction of the hydraulic machine, and the contact surface with the roller has a stepless curved surface having no step in the circumferential direction of the hydraulic machine.

  With the above configuration, the ring cam is an annular body that is continuous in the circumferential direction of the hydraulic machine, and the cam surface forms a stepless curved surface having no step in the circumferential direction, so that the surface pressure rises due to the step of the cam surface. There is no. For this reason, since a large surface pressure is not instantaneously generated on the cam surface or the roller, wear of the ring cam or roller and a decrease in the service life can be avoided.

  According to some embodiments of the present invention, in a radial piston hydraulic machine and a wind power generator equipped with the radial piston hydraulic machine, the ring cam is an annular body that is continuous in the circumferential direction of the hydraulic machine, and the cam Since the surface forms a stepless curved surface having no step in the circumferential direction, the surface pressure does not increase due to the step of the cam surface. For this reason, since a large surface pressure is not instantaneously generated on the cam surface or the roller, wear of the ring cam or roller and a decrease in the service life can be avoided.

It is a schematic diagram of a wind power generator to which a radial piston type hydraulic machine of the present invention is applied. 1 is a longitudinal sectional view of a hydraulic machine according to a first embodiment of the present invention. It is a schematic diagram which shows the structure of the hydraulic fluid path of the said hydraulic machine. It is a cross-sectional view of a ring cam incorporated in the hydraulic machine. It is a cross-sectional view of a ring cam according to a second embodiment of the present invention. It is a longitudinal cross-sectional view of the ring cam which concerns on 3rd Embodiment of this invention. It is explanatory drawing which shows the time of the assembly of the ring cam which concerns on the said 3rd Embodiment. It is a longitudinal cross-sectional view of the ring cam which concerns on 4th Embodiment of this invention. It is explanatory drawing which shows the time of the assembly of the ring cam which concerns on the said 4th Embodiment. It is a longitudinal cross-sectional view of the ring cam which concerns on 5th Embodiment of this invention. It is a perspective view of the ring cam which concerns on 6th Embodiment of this invention. It is sectional drawing which follows the AA line in FIG. It is a perspective view of the ring cam which concerns on 7th Embodiment of this invention. It is a front view of the cylinder block which concerns on the said 7th Embodiment.

  Hereinafter, the present invention will be described in detail with reference to embodiments shown in the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the component parts described in this embodiment are not intended to limit the scope of the present invention to that unless otherwise specified.

(Embodiment 1)
A first embodiment of the present invention will be described with reference to FIGS. In FIG. 1, the wind power generator 10 includes a rotor 12 including at least one, typically two or more blades 14, and a hub 16 in which the blades 14 are radially connected. The hub 16 may be covered with a hub cover 18. A hydraulic pump 22 is connected to the rotor 12 via a rotor shaft 20. A hydraulic motor 28 is connected to the hydraulic pump 22 through a high pressure oil passage 24 and a low pressure oil passage 26. Specifically, the outlet of the hydraulic pump 22 is connected to the inlet of the hydraulic motor 28 via the high pressure oil passage 24, and the outlet of the hydraulic motor 28 is connected to the inlet of the hydraulic pump 22 via the low pressure oil passage 26. .

The hydraulic pump 22 is driven by the rotor shaft 20 to increase the pressure of the hydraulic oil and generate high-pressure hydraulic oil (pressure oil). The high-pressure oil generated by the hydraulic pump 22 is sent to the hydraulic motor 28 via the high-pressure oil passage 24, and the hydraulic motor 28 is driven by this high-pressure oil. The low-pressure hydraulic oil that has worked by the hydraulic motor 28 is returned to the hydraulic motor 28 via the low-pressure oil passage 26.
A generator 30 is connected to the hydraulic motor 28. The generator 30 is a synchronous generator driven by the hydraulic motor 28, and is connected to a power system (not shown).

  Note that at least a part of the rotor shaft 20 is covered with a nacelle 32. The hydraulic pump 22, the hydraulic motor 28, and the generator 30 are disposed inside a nacelle 32 provided at the upper end of the tower 34. In the present embodiment and the embodiments described below, at least one of the hydraulic pump 22 and the hydraulic motor 28 is a radial piston hydraulic machine described below.

  FIG. 2 shows a radial piston type hydraulic machine 40 constituting the hydraulic pump 22 or the hydraulic motor 28. The hydraulic machine 40 includes a plurality of cylinder bores 42 formed along the radial direction of the hydraulic machine 40, a plurality of pistons 44 slidably provided on the plurality of cylinder bores 42, and a plurality of cylinder bores 42. And a cylinder block 48. The plurality of cylinder bores 42 are arranged at equal intervals in the circumferential direction and the axial direction (arrow a direction) of the cylinder block 48. Each piston 44 reciprocates along the radial direction of the hydraulic machine 40 inside the cylinder bore 42. The volume of the hydraulic chamber r formed by the piston 44 and the cylinder bore 42 is periodically changed by the reciprocating motion of the piston 44.

  A rotating shaft 50 is disposed at the center inside the cylinder block 48. When the hydraulic machine 20 is the hydraulic pump 22, the rotary shaft 50 is provided integrally with the rotor shaft 20 or rotates in conjunction with the rotor shaft 20. A ring cam 52 is mounted on the outer peripheral surface of the rotating shaft 50. The ring cam 52 is configured to rotate together with the rotary shaft 50 and has a cam surface that comes into contact with the roller 46 provided on the piston 44. In this case, at least one bearing 54 a may be provided between the ring cam 52 and the cylinder block 48 in order to create a relative rotational movement of the ring cam 52 with respect to the roller 46.

  The motion mode is converted between the reciprocating motion of the piston 44 accompanied with the periodic volume change of the hydraulic chamber r and the rotational motion of the ring cam 52. For example, when the hydraulic machine 40 is the hydraulic pump 22, the rotary motion of the ring cam 52 that rotates with the rotary shaft 50 is converted into the reciprocating motion of the piston 44. As a result, a periodic volume change of the hydraulic chamber r occurs, high pressure hydraulic oil is generated in the hydraulic chamber r, and the hydraulic motor 28 is driven by this high pressure oil.

  When the hydraulic machine 40 is the hydraulic motor 28, high-pressure hydraulic oil is introduced from the hydraulic pump 22, and the reciprocating motion of the piston 44 is caused by the introduction of the high-pressure oil. As a result of the reciprocating motion of the piston 44 being converted into the rotational motion of the ring cam 52, the rotating shaft 50 of the hydraulic machine 40 rotates together with the ring cam 52. Thus, energy conversion is performed between the rotational energy (mechanical energy) of the rotary shaft 50 of the hydraulic machine 40 and the fluid energy of the hydraulic oil by the action of the ring cam 52, and the hydraulic machine 40 is operated by the hydraulic pump 22 or the hydraulic motor 28. As the intended role.

  The cylinder block 48 is formed with at least one internal oil passage 56 (56a, 56b) communicating with the plurality of hydraulic chambers r. In one embodiment, a plurality of internal oil passages 56 (56 a, 56 b) are provided along the axial direction of the hydraulic machine 40. An end plate 60 that is an annular plate member is provided on one end surface of the cylinder block 48. An annular oil collecting passage 58 (58a, 58b) communicating with the plurality of internal oil passages 56 (56a, 56b) is formed inside the end plate 60. In one embodiment, a bearing 54 b is provided between the end plate 60 and the ring cam 52, and the end plate 60 can be kept stationary without being affected by the rotational movement of the ring cam 52.

The annular oil collecting passages 58 (58a, 58b) are connected to the external pipes 62 (62a, 62b), respectively. Thus, each hydraulic chamber r communicates with the external pipe 62 (62a, 62b) via the internal oil passage 56 (56a, 56b) and the annular collecting oil passage 58 (58a, 58b).
In some embodiments, the cylinder block 48 includes a plurality of cylinder sleeves 64 forming the cylinder bore 42 and a cylinder block body 66 having a plurality of sleeve holes 66a into which the plurality of cylinder sleeves 64 are inserted.

  The roles required for the cylinder block 48 include formation of a cylinder bore 42 as a sliding portion for slidably guiding the piston 44 and formation of a structure for holding the cylinder bore 42. As described above, if the cylinder sleeve 64 and the cylinder block main body 66 are provided separately, the roles required for the cylinder block 48 (formation of the cylinder bore 42 and formation of the structure) are the same as the cylinder sleeve 64 and the cylinder block main body 66, respectively. Can be shared. Therefore, a suitable design according to the respective roles of the cylinder sleeve 64 and the cylinder block main body 66 becomes possible, and the weight of the cylinder block 48 as a whole can be realized.

  In FIG. 3, branch oil passages 70a and 70b are connected to the internal oil passages 56 (56a and 56b) and the internal oil passages 56 (56a and 56b) and the hydraulic chambers r of the cylinder sleeves 64, respectively. . The branch oil passages 70a and 70b are provided with on-off valves 72a and 72b, respectively. One of the internal oil passages 56a and 56b is an oil supply passage for supplying hydraulic oil to the hydraulic chamber r, and the other is an oil discharge passage for discharging the hydraulic oil from the hydraulic chamber r.

  The on-off valves 72 a and 72 b are controlled so as to open and close in synchronization with the rotational movement of the ring cam 52 in the circumferential direction. That is, in the stroke from the bottom dead center to the top dead center when the roller 46 in contact with the cam surface of the ring cam 52 is opened, the open / close valve provided in the oil discharge passage is opened and the open / close valve provided in the oil supply passage is closed. . Further, in the stroke of the roller 46 from the top dead center to the bottom dead center, the open / close valve provided in the oil supply passage is opened, and the open / close valve provided in the oil discharge passage is closed. As the on-off valves 72a and 72b, for example, electromagnetic valves or spring-type on-off valves can be used. The spring type on-off valve is provided with a spring for urging the valve body toward the seat surface, and the valve body is closed by a balance between the hydraulic pressure of the hydraulic chamber r, the elastic force of the spring, and the hydraulic pressure of the hydraulic chamber r. And an open position.

  In the exemplary embodiment shown in FIG. 3, the cam surface of the ring cam 52 is alternately formed with crests (lobes) 80 a and troughs 80 b in the circumferential direction.

FIG. 4 shows a ring cam 52 </ b> A as an embodiment of the ring cam 52. The ring cam 52A forms an annular body that is continuous in the circumferential direction (in the direction of arrow b in the drawing and also in the circumferential direction of the hydraulic machine 40). The inner peripheral surface 68 of the ring cam 52A has a circular shape, and is fixed to the circular outer peripheral surface of the hollow rotating shaft 50 by an interference fit. As one means of an interference fit, a shrink fit or a cold fit can be used.
In this way, by fixing the ring cam 52A made of an annular body to the rotating shaft 50 with an interference fit, a bolt hole through which a bolt for fastening the ring cam 52A is inserted on the outer peripheral surface of the rotating shaft 50 is formed in the cam of the ring cam 52A. There is no need to form on the surface. Therefore, the cam surface of the ring cam 52A can be a stepless curved surface with a step formed with a lobe 80a.

  As a result, the surface pressure does not increase due to the step of the cam surface over the entire circumference of the cam surface. For this reason, since a large surface pressure is not instantaneously generated on the cam surface or the roller, wear of the ring cam or roller and a decrease in the service life can be avoided. In addition, since the ring cam 52A is attached to the rotating shaft 50 by interference fitting or cold fitting, the ring cam 52A can be easily attached to the rotating shaft 50.

(Embodiment 2)
Next, a second embodiment of the present invention will be described with reference to FIG. In the present embodiment, a ring cam 52A having the same shape as in the first embodiment is fixed to the outer peripheral surface of the rotary shaft 50 by an interference fit. Further, a plurality of square grooves are formed on the outer peripheral surface of the rotating shaft 50 at equal intervals in the circumferential direction, and the rectangular grooves are formed on the inner peripheral surface of the ring cam 52A at positions corresponding to the grooves. Has been. A key 82 having a quadrangular cross section is press-fitted into the quadrangular hole thus formed. According to this embodiment, in addition to the operational effects obtained in the first embodiment, the relative slip in the circumferential direction of the ring cam 52A with respect to the rotating shaft 40 can be further effectively prevented. Instead of the key 82, another anti-slip member may be used. For example, pin holes may be formed in the ring cam 52A and the rotary shaft 50, and the pins may be inserted into the pin holes.

(Embodiment 3)
Next, a third embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 6, the present embodiment is an example in which the cylinders 42 are arranged in a plurality of rows in the axial direction of the hydraulic machine 40. In the present embodiment, a plurality of pedestals 84 a to 84 d are formed on the outer peripheral surface of the rotating shaft 50 so as to be adjacent to the axial direction (the direction of the arrow a). The pedestals 84a to 84d have circular outer peripheral surfaces with different outer diameters, and the outer peripheral surfaces are concentric with the rotary shaft 50 and have a disk shape with the same plate width. The pedestals 84a to 84d are arranged so that the outer diameters become smaller as they move away from the pedestal 84b having the largest outer diameter in the axial direction. That is, the bases 84a to 84d are arranged in order of increasing outer diameter from the inner side to the outer side of the array.

  The ring cam 52B according to this embodiment includes four annular segments 86a to 86d that are separated from each other. The annular segments 86a to 86d have the same outer diameter, and the inner diameter corresponds to the outer diameter of each of the pedestals 84a to 84d, and is formed of an annular body having a size that can be tightly fitted to the corresponding pedestal. Further, the outer peripheral surface and the inner peripheral surface of the annular segments 86a to 86d have a circular shape that is concentric with each other. The plate width of the annular segment is the same as that of the bases 84a to 84d. The annular segments 86a to 86d are interference fitted to pedestals 84a to 84d having outer diameters that can be interference fitted.

  As shown in FIG. 7, the interference fitting procedure is such that, among the annular segments 86 a to 86 d, the interference fitting is performed in order from the largest inner diameter arranged inside the array. The rollers 46 attached to the pistons 44 are in contact with the outer peripheral surfaces of the annular segments 86a to 86d. Unlike the ring cam 52B of the present embodiment, when a ring cam having a long dimension in the axial direction is shrink-fitted, if the temperature of the ring cam decreases during the shrink-fitting, it may not be possible to fit to the end. .

  In the ring cam 52B of the present embodiment, since the ring cam 52B is divided into annular segments having a short dimension in the axial direction, the interference fit of each annular segment is easy, and the bases 84a to 84a are sequentially arranged in descending order of the inner diameter of the annular segment. Since the interference fitting is performed on 84d, the interference fitting operation is facilitated even for the entire ring cam. In addition, since a step is formed in the radial direction of the ring cam 52B between the pedestals, the positioning of each annular segment is facilitated, and the annular segment can be prevented from coming off in the axial direction.

(Embodiment 4)
Next, a fourth embodiment of the present invention will be described with reference to FIGS. Similar to the third embodiment, in the present embodiment, a plurality of pedestals 88a to 88d having different outer diameters are formed on the outer peripheral surface of the rotating shaft 50 adjacent to each other in the axial direction (arrow a direction). In the present embodiment, the pedestals 88a to 88d are arranged in order of increasing outer diameter from the back side (right side in the drawing). Then, annular segments 90a to 90d having inner diameters corresponding to the pedestals 88a to 88d are prepared.

  And as shown in FIG. 9, it is interference-fitted in order from the base which has the outer diameter corresponding to the annular segment with a large internal diameter in order, ie, the base located in the back | inner side. Also in this embodiment, similarly to the third embodiment, the ring segments are individually divided, so that the interference fitting operation is facilitated as the entire ring cam. In addition, since a step is formed in the radial direction of the ring cam 52C between the pedestals, the positioning of each annular segment is facilitated, and the annular segment can be prevented from coming off in the axial direction.

(Embodiment 5)
Next, a fifth embodiment of the present invention will be described with reference to FIG. In the ring cam 52 </ b> D according to the present embodiment, a circular base plate 92 having a diameter larger than that of the rotating shaft 50 is connected to the end of the rotating shaft 50. A hollow cylindrical portion 94 having the same outer diameter as the base plate 92 is provided. Six annular pedestals 96a to 96f having different inner diameters in the axial direction are formed on the inner peripheral surface of the cylindrical portion 94 so as to be adjacent to each other in the axial direction (arrow a direction). A pedestal with a smaller inner diameter is arranged inside the array. That is, the pedestals 96a to 96f are arranged such that the inner diameter increases as the distance from the pedestal 96c having the smallest inner diameter increases in the axial direction.

  Then, six annular segments 98a to 98f having outer diameters that can be fitted into the respective bases 96a to 96f are prepared. Each annular segment has an outer diameter different from each other and sequentially fits onto a pedestal having an inner diameter of a corresponding dimension. The interference fit is performed in order from a base having a small inner diameter.

  In this way, the cylindrical portion 94 in which each annular segment is mounted on the inner peripheral surface is coupled to the base plate 92 by means such as welding or bolt fastening. The cylinder block 48 is disposed inside the cylindrical portion 94, and the roller 46 attached to the piston 44 comes into contact with the end surfaces of the annular segments 98a to 98f. Thus, the cylindrical portion 94 rotates together with the rotary shaft 50, and the piston 44 reciprocates in conjunction with the rotary motion of the rotary shaft 50 and the cylindrical portion 94. Also in this embodiment, the same operational effects as those of the third and fourth embodiments can be obtained, such as easy mounting of the annular segments 98a to 98d.

(Embodiment 6)
Next, a sixth embodiment of the present invention will be described with reference to FIGS. In this embodiment, the hydraulic machine 40 is the hydraulic pump 22, and the ring cam 52 </ b> E is directly attached to the rotor shaft 20. The ring cam 52E of the present embodiment is disposed adjacent to the rotor shaft 20 in the axial direction of the rotor shaft 20. The ring cam 52E is composed of four annular segments 100a to 100d. The four annular segments 100 a to 100 d are arranged in the axial direction of the rotary shaft 50, and are fixed to the end of the rotor shaft 20 with a plurality of long bolts 102. The plurality of long bolts 102 are arranged at equal intervals in the circumferential direction of the rotor shaft 20. Further, as shown in FIG. 11, the cam surfaces of the annular segments 100a to 100d are arranged so as to be gradually shifted in the circumferential direction (arrow b direction) between one pitch of the lobes 80a.

  According to the present embodiment, since the ring cam 52E is directly attached to the end of the rotor shaft 20, it is not necessary to provide the rotating shaft of the hydraulic pump 22 separately from the ring cam 52E, and the hydraulic pump 22 is simplified and reduced in cost. it can. If the hydraulic machine 40 is the hydraulic motor 28, the ring cam 52E can be directly attached to the rotating shaft of the generator 30. Therefore, the configuration of the hydraulic motor 28 can be simplified and reduced in cost.

  Further, the phase of the reciprocating motion of the piston 44 can be shifted by shifting the phase of the cam surfaces of the annular segments 100a to 100d in the circumferential direction. Therefore, the hydraulic oil discharged from the hydraulic machine 40 can be equalized in time series. Therefore, it is possible to prevent the occurrence of vibration and pulsating flow due to uneven discharge of hydraulic oil.

(Embodiment 7)
Next, a seventh embodiment of the present invention will be described with reference to FIGS. The ring cam 52F of the present embodiment is composed of one annular body 104. The annular body 104 has a center hole 104a penetrating in the axial direction at the center. The annular body 104 is tightly fitted to the outer peripheral surface of the rotor shaft 20 through the center hole 104a. The cam surface of the annular body 104 has a spur gear shape in which the lobe 80a extends linearly toward the axial direction. A plurality of rows of cylinders 42 are arranged on the outer peripheral surface of the annular body 104 along the axial direction.

  Since the ring cam 52F of the present embodiment is formed of a single annular body and the roller 46 extends linearly in the axial direction, the hobbing machine or the surface grinding machine can be used in the axial direction (the direction of the arrow a). ) Can produce a ring cam in one stroke. Therefore, processing of the ring cam is easy and low cost. Moreover, the cam surface which the roller 46 contacted may be worn by the operation of the hydraulic machine over a long period of time. At that time, since the lobe 80a extends linearly toward the axial direction in the ring cam 52F, the roller 46 is not contacted and fresh by moving the ring cam 52F in the axial direction after being used for a predetermined time. The cam surface can be used.

In addition, when using the ring cam 52F of this embodiment, the hydraulic fluid discharged from the hydraulic machine 40 cannot be equalized in time series. Therefore, even when the ring cam 52F is used, a method of equalizing the hydraulic oil discharged from the hydraulic machine 40 in time series by devising the arrangement of the cylinder sleeve 64 provided in the cylinder block 48 in FIG. explain.
In FIG. 14, four cylinder sleeves 64 are provided in the axial direction of the cylinder block 48 (in the direction of arrow a in the drawing) and in the axial direction of the cylinder block 48 (in the direction of arrow a in the drawing). However, although the number is four in the present embodiment, it may be m (two or more) in other embodiments.

The arrangement of the plurality of cylinder sleeves 64 (cylinder arrangement composed of a plurality of cylinder rows R) is different from the virtual arrangement in which a plurality of virtual cylinder rows _R0 arranged in the axial direction of the hydraulic machine 40 are provided. Are formed in accordance with an arrangement in which the circumferential positions of the virtual cylinders belonging to the virtual cylinder row _R0 are different from each other. The virtual array is composed of m virtual cylinder rows R ₀ formed by m virtual cylinders (where m is an integer of 2 or more) arranged in parallel with the axial direction of the hydraulic machine 40 in the circumferential direction (where n is An integer of 2 or more).

In one embodiment, as shown in FIG. 14, a plurality of cylinder sleeves 64 (and cylinder bores 42 provided on them) are arranged according to an arrangement in which the virtual cylinder row R ₀ is inclined at a constant angle c with respect to the axial direction of the hydraulic machine. ) Is arranged. As a result, the circumferential positions of the m cylinder bores 42 arranged in the cylinder block 48 along the axial direction of the hydraulic machine 20 are different from each other. Accordingly, a phase difference can be provided in the axial direction in the reciprocating motion of the piston 44. This arrangement is merely an example, and another arrangement may be used. For example, the cylinder row R may be arranged according to an array of virtual cylinders R ₀ that are partially inclined at two or more different angles.

  When the hydraulic machine 40 is the hydraulic pump 22, the rotation of the rotary shaft 50 can be smoothly performed by equalizing the discharge of the high pressure oil from the high pressure oil passage 24 in time series. Therefore, it is desirable to make a phase difference in the axial direction in the reciprocating motion of the piston 44. For this purpose, the cam surface of the cam 52 is usually provided with a phase difference for each cylinder array arranged in the axial direction. However, this complicates the shape of the cam surface, and the cam surface processing is expensive. Become. Therefore, according to the present embodiment, since the circumferential positions of the m cylinder bores 42 arranged in the cylinder block 48 along the axial direction of the hydraulic machine 20 are different from each other, it is not necessary to provide a phase difference in the shape of the cam surface. , Discharge of high pressure oil can be equalized. Therefore, the cam surface can be easily processed at low cost.

In this embodiment, when the hydraulic machine 40 is the hydraulic motor 28, the ring cam 52F is directly attached to the rotating shaft of the generator 30. As a result, the same effects as those of the hydraulic pump 22 can be obtained. Further, by arranging the cylinder row R according to the arrangement of the virtual cylinders _R0 , the output shaft of the generator 30 can be smoothly rotated. Therefore, the present embodiment can also be applied to the hydraulic motor 28.

  According to the present invention, the step of the cam surface of the ring cam mounted on the radial piston hydraulic machine is eliminated, thereby reducing the surface pressure generated at the contact portion between the roller and the ring cam, thereby reducing the wear of the roller and the ring cam. Abrasion can be eliminated and these lifetimes can be extended.

DESCRIPTION OF SYMBOLS 10 Wind power generator 12 Rotor 14 Blade 16 Hub 18 Hub cover 20 Rotor shaft 22 Hydraulic pump 24 High pressure oil path 26 Low pressure oil path 28 Hydraulic motor 30 Generator 32 Nacelle 34 Tower 40 Hydraulic machine 42 Cylinder bore 44 Piston 46 Contact part 48 Cylinder block 50 Rotating shaft 52, 52A, 52B, 52C, 52D, 52E, 52F Ring cam 54a, 54b Bearing 56, 56a, 56b Internal oil passage 58, 58a, 58b Annular oil passage 60 End plate 62, 62a, 62b External piping 64 Cylinder Sleeve 66 Cylinder block body 66a Sleeve hole 70a, 70b Branch oil passage 72a, 72b On-off valve 80a Mountain (lobe)
80b Valley 82 Key 84a-84d, 88a-88d, 96a-96f Pedestal 86a-86d, 90a-90d, 98a-98f, 100a-100d Annular segment 92 Base plate 94 Cylindrical part 102 Long bolt 104 Annular body 104a Center hole r Hydraulic chamber R Cylinder row R ₀ Virtual cylinder row

Claims (12)

A radial piston type hydraulic machine,
A plurality of pistons arranged along a radial direction of the hydraulic machine;
A plurality of rollers provided rotatably on each of the plurality of pistons;
A cylinder block provided with a plurality of cylinders for respectively guiding the plurality of pistons so as to be capable of reciprocating along the radial direction;
A plurality of lobes arranged in contact with the plurality of rollers, arranged in a circumferential direction of the hydraulic machine, disposed opposite to the plurality of pistons, and relative to the plurality of pistons And a ring cam configured to be rotatable so that the lobe moves in the circumferential direction,
The radial piston hydraulic machine, wherein the ring cam is an annular body continuous in the circumferential direction, and a contact surface with the roller is a stepless curved surface having no step in the circumferential direction.   The radial piston hydraulic machine according to claim 1, further comprising a rotary shaft to which the ring cam is attached by an interference fit.   The anti-slip member provided between the said rotating shaft and the said ring cam for preventing the relative slip in the said circumferential direction of the said ring cam with respect to the said rotating shaft is further provided. Radial piston hydraulic machine. The ring cam is fitted on the outer peripheral surface of the rotary shaft, and includes a plurality of annular segments with different inner diameters arranged in the axial direction of the hydraulic machine,
4. The radial piston hydraulic machine according to claim 2, wherein the plurality of annular segments are arranged such that the inner diameter decreases as the annular segment moves away from the annular segment having the largest inner diameter in the axial direction. 5. The ring cam is fitted on an inner peripheral surface of the rotary shaft, and includes a plurality of annular segments with different outer diameters arranged in the axial direction of the hydraulic machine,
4. The radial piston hydraulic pressure according to claim 2, wherein the plurality of annular segments are arranged such that the outer diameter increases with increasing distance from the annular segment having the smallest outer diameter in the axial direction. 5. machine.   2. The radial according to claim 1, wherein the ring cam is disposed adjacent to an input shaft or an output shaft of the hydraulic machine in the axial direction, and is directly connected to the input shaft or the output shaft. Piston hydraulic machine. The plurality of cylinders are distributed in the axial direction of the hydraulic machine,
The plurality of lobes, respectively, linearly extend in the axial direction over the axial position range in which the plurality of cylinders are distributed. The radial piston hydraulic machine according to one item.   A virtual array in which virtual cylinder rows formed by m virtual cylinders (where m is an integer of 2 or more) arranged in the axial direction are provided in n rows (where n is an integer of 2 or more) in the circumferential direction. On the other hand, the plurality of cylinders are arranged in the cylinder block according to an arrangement in which the circumferential positions of the m virtual cylinders belonging to each of the virtual cylinder rows are different from each other. 8. A radial piston hydraulic machine according to 7. A plurality of pistons arranged along a radial direction of the hydraulic machine, a plurality of rollers rotatably provided on each of the plurality of pistons, and the circumferential direction configured to contact the plurality of rollers A ring cam which has a plurality of lobes arranged along the circumferential direction and is an annular body continuous in the circumferential direction of the hydraulic machine, and a contact surface with the roller is a stepless curved surface having no step in the circumferential direction; and the ring cam A method of assembling a radial piston type hydraulic machine including a rotating shaft to which
A method of assembling a radial piston type hydraulic machine, comprising a cam mounting step of mounting the ring cam on the rotary shaft by an interference fit. The ring cam includes a plurality of annular segments with different inner diameters fitted on the outer peripheral surface of the rotating shaft, and the plurality of annular segments are separated from the annular segment having the largest inner diameter in the axial direction of the hydraulic machine. The axial direction is arranged so that the inner diameter becomes smaller as
10. The radial piston according to claim 9, wherein, in the cam mounting step, an interference fit of the annular segment to the outer peripheral surface of the rotary shaft is performed in an order away from the annular segment having the largest inner diameter in the axial direction. To assemble hydraulic machine. The ring cam includes a plurality of annular segments having different outer diameters that are fitted on the inner peripheral surface of the rotating shaft, and the plurality of annular segments start from the annular segment having the smallest outer diameter to the shaft of the hydraulic machine. Arranged in the axial direction so that the outer diameter increases as the distance in the direction increases,
The said cam attachment step performs an interference fit to the inner peripheral surface of the said rotating shaft of the said annular segment in the order which goes away from the said axial direction from the annular segment with the smallest outer diameter. Assembly method of radial piston hydraulic machine. At least one blade,
A hub to which the at least one blade is mounted;
A hydraulic pump configured to be driven by rotation of the hub;
A hydraulic motor configured to be driven by pressure oil generated by the hydraulic pump;
A wind turbine generator comprising a generator driven by the hydraulic motor,
At least one of the hydraulic pump and the hydraulic motor is a radial piston hydraulic machine,
The hydraulic machine is capable of reciprocating along the radial direction with a plurality of pistons arranged along the radial direction of the hydraulic machine, a plurality of rollers rotatably provided on each of the plurality of pistons. A plurality of cylinders for guiding each of the plurality of pistons, a plurality of lobes arranged in contact with the plurality of rollers and arranged along the circumferential direction, and the plurality of the plurality of cylinders. A ring cam arranged to face the pistons of the plurality of pistons and configured to be rotatable so that the lobes move in the circumferential direction relative to the plurality of pistons,
The ring cam is an annular body that is continuous in the circumferential direction, and the contact surface with the roller is a stepless curved surface having no step in the circumferential direction.

Images