JP2004239067A - Rotary fluid machinery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent leakage of an operating medium by enhancing follow-up performance of a siding surface of a rotary valve of rotary fluid machinery. <P>SOLUTION: The rotary valve 71 of the rotary fluid machinery is formed by allowing a movable side valve plate 74 arranged in a rotor 22 and a fixed side valve plate 73 arranged in a valve body part 72 to abut on the sliding surface 77 orthogonal to the axis L. An annular member 104 rockably pivots the valve body part 72 by a support shaft 103, and is locked on a pair of guide grooves 18c of a rear cover 18 so that a pair of projections 104a and 104b projected on both ends in the diametral direction can freely slide in the axis L direction. When energizing the valve body part 72 in the axis L direction for bringing the sliding surface 77 into close contact, since the annular member 104 is prevented from inclining from a plane orthogonal to the axis L when the two projections 104a and 104b uniformly receive sliding resistance from the guide grooves 18c, leakage of the operating medium can be prevented by securing the follow-up performance of the sliding surface 77, and partial abrasion of the sliding surface 77 can be restrained. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a casing, a rotor rotatably supported by the casing, an operating portion provided on the rotor, and a rotary valve provided between the casing and the rotor to control supply and discharge of a working medium to and from the operating portion. And a rotary fluid machine having the same.
[0002]
[Prior art]
A rotary valve of this type of rotary fluid machine includes a movable valve plate provided on a rotor, and a fixed valve plate provided on a valve body which is non-rotatably fixed to a casing and movably movable in the axial direction of the rotor. Are brought into contact with each other on a sliding surface perpendicular to the axis, so that high-temperature and high-pressure steam is sequentially supplied and discharged to an axial piston cylinder group provided on the rotor by relative rotation of the movable side valve plate with respect to the fixed side valve plate. Has become. At this time, the frictional force acting on the sliding surface between the movable side valve plate and the fixed side valve plate that rotates together with the rotor prevents the valve body portion integrated with the fixed side valve plate from being dragged by the rotor and rotating. It is necessary to secure the followability of the sliding surface by permitting the valve body to move in the axial direction while preventing it.
[0003]
Therefore, in the rotary fluid machine described in the following patent document, a pin radially implanted at one position on the outer peripheral surface of the valve body is engaged with a notch formed in the axial direction on the inner peripheral surface of the casing. .
[0004]
[Patent Document]
JP-A-2002-256805 [0005]
[Problems to be solved by the invention]
By the way, the valve body accommodated in the recess of the casing via the seal member swings around the axis within the range of the collapse of the seal member so that the sliding surface of the movable-side valve plate and the fixed-side valve plate can be moved. Follow-up. However, in the above-described conventional device, since only one portion of the outer peripheral surface of the valve body is locked to the casing by the pin, the valve body cannot smoothly swing around the axis, and the valve body cannot be swung from the axis. When the valve body swings around the pin located at the eccentric position, not only the followability of the sliding surface may be reduced, but also the sliding surface may be unevenly worn.
[0006]
The present invention has been made in view of the above circumstances, and has as its object to prevent leakage of a working medium by improving the followability of a sliding surface of a rotary valve of a rotary fluid machine.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, according to the invention described in claim 1, a casing, a rotor rotatably supported by the casing, an operating portion provided on the rotor, and a casing provided between the casing and the rotor are provided. A rotary valve for controlling the supply and discharge of the working medium to and from the working portion, the rotary valve being locked to a movable valve plate provided on the rotor and to a casing so as to be non-rotatable and movable in the axial direction of the rotor. The first diameter of the annular member loosely fitted to the outer periphery of the valve body in a rotary fluid machine in which the fixed valve plate provided on the valve body is brought into contact with a sliding surface orthogonal to the axis. Two protrusions projecting at both ends in the direction are slidably engaged with guide grooves formed in the casing in the axial direction, and are orthogonal to the first diameter direction. Rotating fluid machine is proposed which is characterized in that the pivotally supported swingably valve body to the annular member via a support shaft disposed in the second radial direction.
[0008]
According to the above configuration, two projections are provided at both ends in the first diameter direction of the annular member loosely fitted to the outer periphery of the valve body of the rotary valve of the rotary fluid machine, and the projections are formed on the casing. Since the valve body is slidably engaged with the guide groove in the axial direction, two projections are formed when the valve body is urged in the axial direction to bring the sliding surface between the fixed valve plate and the movable valve plate into close contact. Receives the sliding resistance uniformly from the guide groove of the casing, thereby preventing the annular member from tilting from a plane perpendicular to the axis. Even if the annular member is inclined due to a difference in sliding resistance that the two projections receive from the guide groove, the valve body is pivotally supported on the annular member via a support shaft arranged in the second diametrical direction. As a result, the valve main body is reliably prevented from tilting with respect to the axis L, the followability of the sliding surface is ensured, the leakage of the working medium is prevented, and the uneven wear of the sliding surface is suppressed. be able to.
[0009]
According to the second aspect of the present invention, in addition to the first aspect, the two protrusions of the annular member are slidable in the first diametric direction with respect to the guide groove of the casing, and A rotary fluid machine is proposed, wherein the valve body is slidable in a second diametrical direction along a support shaft.
[0010]
According to the above configuration, the valve body can freely move in a plane perpendicular to the axis with respect to the casing by the action of the Oldham coupling formed by the annular member and the support shaft. Therefore, even if the valve body is inclined with respect to the axis, the valve body is free to move in a plane perpendicular to the axis, thereby preventing the occurrence of stiffness between the casing and the casing. Surface followability can be ensured.
[0011]
Note that the axial piston cylinder group 56 of the embodiment corresponds to the operating section of the present invention.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described based on examples of the present invention shown in the accompanying drawings.
[0013]
1 to 16 show a first embodiment of the present invention. FIG. 1 is a longitudinal sectional view of an expander, FIG. 2 is a sectional view taken along line 2-2 in FIG. 1, and FIG. 3 is 3-3 in FIG. 4 is an enlarged view of a part 4 of FIG. 1, FIG. 5 is an enlarged view of a part 5 of FIG. 1, FIG. 6 is an exploded perspective view of the rotor, FIG. 7 is a sectional view taken along the line 7-7 of FIG. 8 is a sectional view taken along line 8-8 in FIG. 4, FIG. 9 is an enlarged view of a part 9 in FIG. 4, FIG. 10 is a sectional view taken along line 10-10 in FIG. 5, FIG. 12 is a sectional view taken along line 12-12 of FIG. 5, FIG. 13 is a sectional view taken along line 13-13 of FIG. 5, FIG. 14 is a view taken in the direction of arrow 14 in FIG. 13, FIG. FIG. 2 is an exploded perspective view of an Oldham coupling.
[0014]
As shown in FIGS. 1 to 9, the expander E of this embodiment is used in, for example, a Rankine cycle device, and converts heat energy and pressure energy of a high-temperature high-pressure steam as a working medium into mechanical energy and outputs the mechanical energy. I do. The casing 11 of the expander E includes a casing body 12, a front cover 15 connected to a front opening of the casing body 12 by a plurality of bolts 14 via a sealing member 13, and a rear opening of the casing body 12. A rear cover 18 connected to the casing body 12 with a plurality of bolts 17 via a sealing member 16 and an oil pan 21 connected to an opening on the lower surface of the casing body 12 via a sealing member 19 with a plurality of bolts 20. It consists of.
[0015]
A rotor 22 rotatably arranged around an axis L extending in the front-rear direction at the center of the casing 11 is supported by combined angular bearings 23f, 23r having a front portion provided on the front cover 15, and a rear portion of the casing body 12 is provided. And is supported by a radial bearing 24 provided at the bottom. A swash plate holder 28 is integrally formed on the rear surface of the front cover 15, and a swash plate 31 is rotatably supported by the swash plate holder 28 via an angular bearing 30. The axis of the swash plate 31 is inclined with respect to the axis L of the rotor 22, and the angle of inclination is fixed.
[0016]
The rotor 22 includes an output shaft 32 supported on the front cover 15 by combined angular bearings 23f and 23r, and cutouts 57 and 58 (see FIGS. 4 and 9) having predetermined widths at the rear of the output shaft 32. The three integrally formed sleeve support flanges 33, 34, 35 are connected to the rear sleeve support flange 35 by a plurality of bolts 37 via a metal gasket 36. And a heat insulating cover 40 which is fitted to the three sleeve support flanges 33, 34, 35 from the front and is connected to the front sleeve support flange 33 by a plurality of bolts 39. .
[0017]
Each of the three sleeve support flanges 33, 34, 35 is formed with five sleeve support holes 33a,..., 34a, 35a at intervals of 72 ° around the axis L. The sleeve support holes 33a,. Five cylinder sleeves 41 are fitted into 34a, 35a from behind. A flange 41a is formed at the rear end of each cylinder sleeve 41. The flange 41a is fitted to the metal gasket 36 in a state where the flange 41a is fitted to a step 35b formed in the sleeve support hole 35a of the rear sleeve support flange 35. It is positioned in the axial direction by contact (see FIG. 9). A piston 42 is slidably fitted inside each of the cylinder sleeves 41. A front end of the piston 42 abuts a dimple 31a formed on the swash plate 31, and a piston 42 and a rotor head 38 A steam expansion chamber 43 is defined therebetween.
[0018]
A plate-shaped bearing holder 92 is superimposed on the front surface of the front cover 15 via a sealing member 91 and fixed with bolts 93. A pump body 95 is superimposed on the front surface of the bearing holder 92 via a sealing member 94. It is fixed with bolts 96. The combined angular bearings 23f and 23r are fixed between the stepped portion of the front cover 15 and the bearing holder 92 in the direction of the axis L.
[0019]
A shim 97 having a predetermined thickness is sandwiched between a flange 32d formed on the output shaft 32 supporting the combined angular bearings 23f and 23r and an inner race of the combined angular bearings 23f and 23r, and screwed to the outer periphery of the output shaft 32. The inner race of the combined angular bearings 23f and 23r is tightened by the nut 98. As a result, the output shaft 32 is positioned in the direction of the axis L with respect to the combined angular bearings 23f and 23r, that is, with respect to the casing 11.
[0020]
The combined angular bearings 23f and 23r are mounted in opposite directions, and not only support the output shaft 32 in the radial direction but also support the output shaft 32 so as not to be movable in the axis L direction. That is, one combination angular bearing 23f restricts the output shaft 32 from moving forward, and the other combination angular bearing 23r restricts the output shaft 32 from moving rearward.
[0021]
Since the combined angular bearings 23f and 23r are used for the bearing that supports the front part of the rotor 22, the load generated on the both sides in the direction of the axis L generated in the expansion chambers 43 in the predetermined operating state of the expander E is one of the rotors. 22 is transmitted to the inner race of the combined angular bearings 23f, 23r, and the other is transmitted to the outer race of the combined angular bearings 23f, 23r via the swash plate 31 and the swash plate holder 28 of the front cover 15. These two loads compress the swash plate holder 28 of the front cover 15 sandwiched between the angular bearing 30 that supports the swash plate 31 and the combined angular bearings 23f and 23r that support the rotor 22. The rigidity is high. In addition, as in the present embodiment, by forming the swash plate holder 28 integrally with the front cover 15, a simple structure having higher rigidity is obtained.
[0022]
Further, by incorporating the angular bearings 30 for supporting the swash plate 31 and the combined angular bearings 23f and 23r for supporting the rotor 22 into the front cover 15, the “rotor 22 and pistons 42. , "Pump body 95" can be assembled, and the efficiency of operations such as rearrangement of pistons 42 and replacement of oil pump 49 is improved.
[0023]
The radial bear 24 supporting the rotor head 38 constituting the rear end portion of the rotor 22 is a normal ball bearing that supports only a radial load, and the rotor head 38 moves in the direction of the axis L with respect to the radial bearing 24. A gap α (see FIG. 5) is formed between the rotor head 38 and the inner race of the radial bearing 24 so that the rotor head 38 can slide.
[0024]
An oil passage 32a extending on the axis L is formed inside the output shaft 32 integrated with the rotor 22, and the front end of the oil passage 32a branches radially and communicates with an annular groove 32b on the outer periphery of the output shaft 32. An oil passage closing member 45 is screwed into the inner periphery of the oil passage 32a via a seal member 44 at a position radially inward of the sleeve support flange 34 at the center of the rotor 22. A plurality of oil holes 32c extending outward in the direction open in the outer peripheral surface of the output shaft 32.
[0025]
A trochoid-type oil pump 49 disposed between a concave portion 95a formed on the front surface of the pump body 95 and a pump cover 48 fixed to the front surface of the pump body 95 with a plurality of bolts 47 via a seal member 46 is provided. An outer rotor 50 rotatably fitted in the recess 95a, and an inner rotor 51 fixed to the outer periphery of the output shaft 32 and meshing with the outer rotor 50. The internal space of the oil pan 21 communicates with a suction port 53 of an oil pump 49 via an oil pipe 52 and an oil passage 95b of a pump body 95, and a discharge port 54 of the oil pump 49 communicates with an oil passage 95c of the pump body 95. The output shaft 32 communicates with the annular groove 32b.
[0026]
The piston 42 slidably fitted to the cylinder sleeve 41 includes an end portion 61, an intermediate portion 62, and a top portion 63. The end portion 61 is a member having a spherical portion 61a that comes into contact with the dimple 31a of the swash plate 31, and is joined to the tip of the intermediate portion 62 by welding. The intermediate portion 62 is a cylindrical member having a large-capacity hollow space 62a, and has a small-diameter portion 62b whose diameter is slightly reduced at an outer peripheral portion near the top portion 63, and penetrates therethrough in the radial direction. Are formed as described above, and a plurality of spiral oil grooves 62d are formed in the outer peripheral portion in front of the small diameter portion 62b. The top portion 63 facing the expansion chamber 43 is formed integrally with the intermediate portion 62, and a heat insulating space 65 is provided between a partition wall 63a formed on the inner surface thereof and a lid member 64 fitted and welded to its rear end surface. (See FIG. 9) is formed. Two compression rings 66, 66 and one oil ring 67 are mounted on the outer periphery of the top portion 63, and an oil ring groove 63b in which the oil ring 67 fits is inserted through a plurality of oil holes 63c. It communicates with the hollow space 62a of the intermediate part 62.
[0027]
The end portion 61 and the intermediate portion 62 of the piston 42 are made of high carbon steel, and the top portion 63 is made of stainless steel. The end portion 61 is induction hardened and the intermediate portion 62 is hardened. As a result, a high surface pressure resistance of the end portion 61 abutting against the swash plate 31 with a large surface pressure, a wear resistance of the intermediate portion 62 slidably contacting the cylinder sleeve 41 under severe lubrication conditions, and a high temperature and high pressure The heat resistance and corrosion resistance of the top portion 63 exposed to water are satisfied.
[0028]
An annular groove 41b (see FIGS. 6 and 9) is formed on the outer periphery of the intermediate portion of the cylinder sleeve 41, and a plurality of oil holes 41c are formed in the annular groove 41b. Regardless of the mounting position of the cylinder sleeve 41 in the rotation direction, an oil hole 32c formed in the output shaft 32 and an oil hole 34b formed in the center sleeve support flange 34 of the rotor 22 (see FIGS. 4 and 6). Communicates with the annular groove 41b. Spaces 68 formed between the sleeve support flanges 33 and 35 on the front and rear sides of the rotor 22 and the heat insulating cover 40 are formed via oil holes 40a formed in the heat insulating cover 40 (see FIGS. 4 and 7). It communicates with the internal space of the casing 11.
[0029]
An annular lid member 69 is welded to the front side or the expansion chamber 43 side of the rotor head 38 which is connected to the rear surface of the sleeve support flange 33 on the front side of the rotor 22 with bolts 37. An annular heat insulating space 70 (see FIG. 9) is defined. The rotor head 38 is positioned in the rotation direction with respect to the rear sleeve support flange 35 by the knock pin 55.
[0030]
The five cylinder sleeves 41 and the five pistons 42 constitute an axial piston cylinder group 56 of the present invention.
[0031]
Next, the structure of the rotary valve 71 for supplying and discharging steam to and from the five expansion chambers 43 of the rotor 22 will be described with reference to FIG. 5 and FIGS.
[0032]
As shown in FIG. 5, a rotary valve 71 arranged along the axis L of the rotor 22 includes a valve body 72 and a cap member 102 fitted on the rear outer periphery of the valve body 72 via a seal member 101. An annular member 104 loosely fitted to the outer periphery of the intermediate portion of the valve body 72 and supported by the support shaft 103 so as to be swingable, a fixed valve plate 73, and a movable valve plate 74. The movable valve plate 74 is fixed to the rear surface of the rotor 22 with bolts 76 screwed to the oil passage closing member 45 (see FIG. 4) while being positioned in the rotation direction by the knock pin 75. The bolt 76 also has a function of fixing the rotor head 38 to the output shaft 32.
[0033]
As is clear from FIG. 5 with reference to FIGS. 13 to 16, the annular member 104 includes a pair of protrusions 104 a and 104 b at both ends in the first diametric direction XX. The projections 104a and 104b have a rectangular cross section with chamfered corners. The projections 104a and 104b have a pair of guide grooves 18c and 18c formed in the rear cover 18 in the direction of the axis L, and are provided in the axis L direction and the radial direction (first diametric direction). XX) so as to be slidable. The support shaft 103 press-fitted into the two through holes 104c, 104c formed in the annular member 104 is disposed in a second diameter direction YY orthogonal to the first diameter direction XX. The support shaft 103 penetrates loosely through the valve body 72, so that the valve body 72 is slidable in the second diametric direction Y-Y with respect to the annular member 104, and with respect to the annular member 104. It can swing around the support shaft 103.
[0034]
That is, the annular member 104 is relatively movable in the first diametric direction XX by the engagement between the projections 104a, 104b and the guide grooves 18c, 18c with respect to the rear cover 18, and the valve main body 72 is supported by the support shaft. The valve body 72 can be freely moved relative to the rear cover 18 in a plane orthogonal to the axis L because the valve body 72 is relatively movable in the second diametric direction Y-Y while being guided by the 103. Accordingly, the annular member 104 and the support shaft 103 constitute an Oldham coupling that allows the axial displacement between the rear cover 18 and the valve body 72 while restricting the rotation of the valve body 72 with respect to the rear cover 18.
[0035]
Returning to FIG. 5, the fixed-side valve plate 73, which comes into contact with the movable-side valve plate 74 via a flat sliding surface 77, is fixed to the center of the front surface of the valve body 72 with one bolt 78, and It is fixed to the outer peripheral portion of the main body 72 by an annular fixing ring 79 and a plurality of bolts 80. At this time, a step portion 79a formed on the inner periphery of the fixing ring 79 is press-fitted so as to fit into the outer periphery of the fixed side valve plate 73, and a step portion 79b formed on the outer periphery of the fixing ring 79 is inserted into the valve body portion. By fitting into the outer periphery of the 72, the coaxiality of the fixed-side valve plate 73 with respect to the valve body 72 is ensured. A knock pin 81 for positioning the fixed-side valve plate 73 in the rotation direction is disposed between the valve body 72 and the fixed-side valve plate 73.
[0036]
Therefore, when the rotor 22 rotates, the movable-side valve plate 74 and the fixed-side valve plate 73 relatively rotate while closely contacting each other on the sliding surface 77. The fixed-side valve plate 73 and the movable-side valve plate 74 are made of a highly durable material such as carbon or ceramic, and the sliding surface 77 has heat resistance, lubricity, corrosion resistance, and wear resistance. The durability can be further improved by interposing or coating a member having the following.
[0037]
The cap member 102 fitted to the outer periphery of the valve body 72 has a large-diameter portion 102a and a small-diameter portion 102b, and the outer peripheral surfaces of the large-diameter portion 102a and the small-diameter portion 102b are interposed via seal members 82 and 83, respectively. The rear cover 18 is slidably fitted to the support surfaces 18a and 18b having a circular cross section in the direction of the axis L.
[0038]
A plurality of preload springs 85 are supported by the rear cover 18 so as to surround the axis L, and the preload springs 85 press the step portion 102c between the large-diameter portion 102a and the small-diameter portion 102b. Is urged forward to bring the sliding surfaces 77 of the fixed valve plate 73 and the movable valve plate 74 into close contact.
[0039]
The steam supply pipe 86 connected to the rear surface of the valve body 72 slides through a first steam passage P1 formed inside the valve body 72 and a second steam passage P2 formed in the fixed valve plate 73. It communicates with the moving surface 77. Further, a steam discharge chamber 88 sealed with a seal member 87 is formed between the casing body 12 and the rear cover 18 and the rotor 22, and the steam discharge chamber 88 is formed in a sixth body formed inside the valve body 72. , The seventh steam passages P6 and P7, and the fifth steam passage P5 formed in the fixed-side valve plate 73, and communicates with the sliding surface 77. At the mating surface of the valve body 72 and the fixed-side valve plate 73, a seal member 89 surrounding the connection between the first and second steam passages P1 and P2, and the connection between the fifth and sixth steam passages P5 and P6. Is provided.
[0040]
Five third steam passages P3... Arranged at equal intervals so as to surround the axis L pass through the movable side valve plate 74, and five fourth steam passages P3 formed in the rotor 22 so as to surround the axis L. Both ends of the steam passages P4 communicate with the third steam passages P3 and the expansion chambers 43, respectively. The portion of the second steam passage P2 that opens to the sliding surface 77 is circular, whereas the portion of the fifth steam passage P5 that opens to the sliding surface 77 is formed in an arc shape centered on the axis L.
[0041]
Next, the operation of the expander E of the present embodiment having the above configuration will be described.
[0042]
The high-temperature and high-pressure steam generated by heating water in the evaporator is supplied from a steam supply pipe 86 to a first steam passage P1 formed in the valve body 72 of the rotary valve 71, and a fixed-side valve plate 73 integrated with the valve body 72. And reaches the sliding surface 77 with the movable side valve plate 74 via the second steam passage P2 formed at the second position. The second steam passage P2 opening to the sliding surface 77 instantaneously communicates with a corresponding third steam passage P3 formed in the movable valve plate 74 that rotates integrally with the rotor 22 during a predetermined intake period, and the high temperature and high pressure The steam is supplied from the third steam passage P3 to the expansion chamber 43 in the cylinder sleeve 41 via the fourth steam passage P4 formed in the rotor 22.
[0043]
Even after the communication between the second steam passage P2 and the third steam passage P3 is cut off with the rotation of the rotor 22, the high-temperature and high-pressure steam expands in the expansion chamber 43, so that the piston 42 fitted to the cylinder sleeve 41 is moved. It is pushed forward from the top dead center toward the bottom dead center, and the end part 61 at the front end presses the dimple 31 a of the swash plate 31. As a result, a rotational torque is applied to the rotor 22 by the reaction force received by the piston 42 from the swash plate 31. Then, each time the rotor 22 rotates one fifth, the high-temperature and high-pressure steam is supplied into the adjacent new expansion chamber 43, and the rotor 22 is continuously driven to rotate.
[0044]
While the piston 42 that has reached the bottom dead center with the rotation of the rotor 22 is pressed by the swash plate 31 and retreats toward the top dead center, the low-temperature and low-pressure steam pushed out of the expansion chamber 43 is The fourth steam passage P4, the third steam passage P3 of the movable-side valve plate 74, the sliding surface 77, the arc-shaped fifth steam passage P5 of the fixed-side valve plate 73, and the sixth and fifth passages of the valve body 72. The steam is discharged to the steam discharge chamber 88 through the steam passages P6 and P7, and is supplied to the condenser therefrom.
[0045]
The oil pump 49 provided on the output shaft 32 is operated with the rotation of the rotor 22, and the oil sucked from the oil pan 21 through the oil pipe 52, the oil passage 95 b of the pump body 95, and the suction port 53 is discharged from the discharge port 54. The oil is discharged, the oil passage 95c of the pump body 95, the oil passage 32a of the output shaft 32, the annular groove 32b of the output shaft 32, the oil hole 32c of the output shaft 32, the annular groove 41b of the cylinder sleeve 41 and the oil hole of the cylinder sleeve 41. Are supplied to the space between the small-diameter portion 62b formed in the intermediate portion 62 of the piston 42 and the cylinder sleeve 41 via the cylinder sleeve 41. A part of the oil held in the small diameter portion 62b flows into a spiral oil groove 62d formed in the intermediate portion 62 of the piston 42 to lubricate the sliding surface with the cylinder sleeve 41, The other part lubricates the sliding surfaces of the compression sleeves 66, 66 and the oil ring 67 provided on the top part 63 of the piston 42 and the cylinder sleeve 41.
[0046]
It is inevitable that the water in which a part of the supplied high-temperature and high-pressure steam condenses enters the sliding surfaces of the cylinder sleeve 41 and the piston 42 from the expansion chamber 43 and mixes with the oil. Although the conditions become severe, the necessary amount of oil is supplied directly from the oil pump 49 through the inside of the output shaft 32 to the sliding surfaces of the cylinder sleeve 41 and the piston 42, thereby maintaining a sufficient oil film and improving the lubrication performance. As a result, the size of the oil pump 49 can be reduced.
[0047]
The oil scraped off from the sliding surfaces of the cylinder sleeve 41 and the piston 42 by the oil ring 67 flows into the hollow space 62a inside the piston 42 from the oil holes 63c formed at the bottom of the oil ring groove 63b. The hollow space 62a communicates with the inside of the cylinder sleeve 41 through a plurality of oil holes 62c penetrating the intermediate portion 62 of the piston 42, and the inside of the cylinder sleeve 41 communicates through a plurality of oil holes 41c. It communicates with an annular groove 41b on the outer periphery of the cylinder sleeve 41. The periphery of the annular groove 41b is covered by a sleeve support flange 34 at the center of the rotor 22. Since the oil hole 34b is formed in the sleeve support flange 34, the oil in the hollow space 62a of the piston 42 is subjected to centrifugal force. , And is discharged to the space 68 in the heat insulating cover 40 through the oil hole 34b of the sleeve support flange 34, and then returned to the oil pan 21 through the oil hole 40a of the heat insulating cover 40. At this time, since the oil hole 34b is located at a position deviated toward the axis L from the radially outer end of the sleeve support flange 34, the oil radially outside of the oil hole 34b is centrifugally applied to the piston 42. It is held in the hollow space 62a.
[0048]
As described above, the oil held in the hollow space 62a inside the piston 42 and the oil held in the small diameter portion 62b on the outer periphery of the piston 42 combine with the small diameter portion 62b during the expansion stroke in which the volume of the expansion chamber 43 increases. From the small diameter portion 62b to the end portion 61 during the compression stroke in which the volume of the expansion chamber 43 is reduced, so that the entire axial direction of the piston 42 can be reliably lubricated. . In addition, since the oil flows inside the hollow space 62a of the piston 42, the heat of the top portion 63 exposed to the high-temperature and high-pressure steam is transmitted to the low-temperature end portion 61 to prevent the temperature of the piston 42 from locally increasing. can do.
[0049]
When the high-temperature and high-pressure steam is supplied from the fourth steam passage P4 to the expansion chamber 43, an adiabatic space 65 is formed between the top part 63 and the intermediate part 62 of the piston 42 facing the expansion chamber 43. Since the heat insulating space 70 is also formed in the rotor head 38 facing the chamber 43, it is possible to minimize the heat escape from the expansion chamber 43 to the piston 42 and the rotor head 38 and contribute to the improvement of the performance of the expander E. it can. Further, since the hollow space 62a having a large volume is formed inside the piston 42, not only the weight of the piston 42 can be reduced, but also the heat mass of the piston 42 is reduced, so that the heat can escape from the expansion chamber 43 more effectively. Can be reduced.
[0050]
Since the expansion chamber 43 is sealed by interposing the metal gasket 36 between the rear sleeve support flange 35 and the rotor head 38, the expansion chamber 43 is sealed with a thick annular sealing member. As a result, the dead volume around the seal can be reduced, whereby a large volume ratio (expansion ratio) of the expander E can be ensured, the thermal efficiency can be increased, and the output can be improved. Further, since the cylinder sleeve 41 is formed separately from the rotor 22, the material of the cylinder sleeve 41 can be selected in consideration of heat conductivity, heat resistance, strength, abrasion resistance and the like without being limited by the material of the rotor 22. It is economical because only the worn or damaged cylinder sleeve 41 can be replaced.
[0051]
Further, since the outer peripheral surface of the cylinder sleeve 41 is exposed from two notches 57 and 58 formed in the outer peripheral surface of the rotor 22 in the circumferential direction, not only can the weight of the rotor 22 be reduced, but also the heat mass of the rotor 22 can be reduced. As a result, the cutouts 57 and 58 function as a heat insulating space, whereby heat escape from the cylinder sleeve 41 can be suppressed. Further, since the outer peripheral portion of the rotor 22 is covered with the heat insulating cover 40, heat escape from the cylinder sleeve 41 can be more effectively suppressed.
[0052]
Since the rotary valve 71 supplies and discharges steam to the axial piston cylinder group 56 via the flat sliding surface 77 between the fixed valve plate 73 and the movable valve plate 74, it is possible to effectively prevent steam leakage. Can be. This is because the flat sliding surface 77 can be easily processed with high precision, so that the clearance can be easily managed as compared with the cylindrical sliding surface. Moreover, since a plurality of preload springs 85 apply a preset load to the valve body 72 to generate a surface pressure on the sliding surfaces 77 of the fixed-side valve plate 73 and the movable-side valve plate 74, steam from the sliding surface 77 is generated. Leakage can be more effectively suppressed.
[0053]
When the valve body 72 is urged by the preload springs 85 to bring the fixed-side valve plate 73 and the movable-side valve plate 74 into close contact with the sliding surface 77, an annular member 104 that supports the valve body 72 on the rear cover 18. However, the pair of projections 104a, 104b projecting from both ends in the first diameter direction XX are guided by the guide grooves 18c, 18c of the rear cover 18 so as to be slidable in the axis L direction. The inclination of the annular member 104 is prevented by receiving the sliding resistance evenly from the guide grooves 18c, 18c of the rear cover 18 by the 104a, 104b.
[0054]
Even if the pair of protrusions 104a, 104b are inclined by receiving uneven sliding resistance from the guide grooves 18c, 18c, the valve body 72 is supported on the annular member 104 in the second diametric direction YY. Since it is pivotally supported via 103, the inclination of the valve body 72 is reliably prevented. Accordingly, the followability of the sliding surface 77 of the fixed valve plate 73 and the movable valve plate 74 can be ensured, the leakage of high-temperature and high-pressure steam can be prevented, and the uneven wear of the sliding surface 77 can be suppressed.
[0055]
Further, by the action of the Oldham coupling constituted by the annular member 104 and the support shaft 103, the annular member 104 can move in the first diametrical direction XX with respect to the rear cover 18, and the valve main body 72 becomes annular. Since the valve body 72 is movable in the second diametric direction Y-Y with respect to the member 104, the valve body 72 can freely move in a plane perpendicular to the axis L with respect to the rear cover 18. Therefore, even if the valve body 72 is inclined with respect to the axis L, the occurrence of stiffness between the valve body 72 and the rear cover 18 due to the free movement of the valve body 72 in a plane perpendicular to the axis L is prevented. Thus, the followability of the sliding surface 77 can be further improved.
[0056]
The valve body 72 of the rotary valve 71 is made of stainless steel having a large thermal expansion, and the fixed valve plate 73 fixed to the valve body 72 is made of carbon or ceramic having a small thermal expansion. There is a possibility that the centering between the two may deviate due to the difference in the amount, but the inner step 79a of the fixing ring 79 is press-fitted into the outer periphery of the fixed side valve plate 73 by in-row fitting, and The fixing ring 79 is fixed to the valve body 72 with a plurality of bolts 80 in a state where the portion 79b is fitted in the outer periphery of the valve body 72. The center of the valve 73 is precisely centered on the valve body 72 to prevent the steam supply / discharge timing from being shifted, thereby improving the performance of the expander E. It is possible to prevent the bottom. Moreover, the contact surface between the fixed side valve plate 73 and the valve body 72 is uniformly brought into close contact with the fastening force of the bolts 80, and the leakage of steam from the contact surface can be suppressed.
[0057]
Furthermore, since the rotary valve 71 can be attached to and detached from the casing body 12 simply by removing the rear cover 18 from the casing body 12, maintenance workability such as repair, cleaning, and replacement is greatly improved. Although the rotary valve 71 through which the high-temperature and high-pressure steam passes becomes hot, the swash plate 31 and the output shaft 32 which require lubrication with oil are arranged on the opposite side of the rotary valve 71 with the rotor 22 interposed therebetween. The lubrication performance of the swash plate 31 and the output shaft 32 can be prevented from lowering due to the oil being heated by the heat of the rotary valve 71. The oil also has a function of cooling the rotary valve 71 to prevent overheating.
[0058]
By the way, when assembling the expander E, the size of the dead volume between the bottom of the cylinder sleeve 41 (that is, the lid member 69 supported by the rotor head 38) and the top of the piston 42, that is, the piston 42 is at the top dead center. It is necessary to adjust the volume of the working chamber 43 at that time. When the shim 97 interposed between the flange 32d of the output shaft 32 and the inner races of the combined angular bearings 23f and 23r is thinned, the output shaft 32 moves forward (to the right in FIG. 1), so that the rotor head 38 also moves forward. Although moving, the piston 42 is restricted by the swash plate 31 and cannot move forward, so that the dead volume is reduced. Conversely, when the shim 97 is thickened, the dead volume increases because the rotor head 38 moves rearward (to the left in FIG. 1) together with the output shaft 32. As a result, it is possible to arbitrarily adjust the dead volume only by replacing the shim 97, and the time required for adjusting the dead volume can be eliminated, thereby greatly reducing the time.
[0059]
Further, a single shim 97 having a predetermined thickness is interposed between the flange 32d of the output shaft 32 and the angular bearings 23f and 23r, and an angular bearing 30 for supporting the swash plate 31 and an angular bearing for supporting the rotor 22. The dead volume can be adjusted by simply tightening the front cover 15 incorporating the 23f, 23r and the rotor 22 incorporating the pistons 42 with one nut 98, so that the thickness of the conventional front and rear two shims can be adjusted. The adjustment work can be performed easily as compared with the case where each is adjusted. Moreover, when adjusting the dead volume, the rotor 22 incorporating the pistons 42 may be left attached to the casing main body 12. Therefore, the work of checking the dead volume after the adjustment is performed by directly watching the contact state between the pistons 42 and the swash plate 31. Will be able to do it.
[0060]
As described above, when the position of the output shaft 32 is adjusted to the front and rear with respect to the combined angular bearings 23f and 23r by changing the thickness of the shim 97, the position of the rotor head 38 at the rear end of the rotor 22 is also adjusted to the front and rear. However, since the rotor head 38 is slidable in the direction of the axis L with respect to the inner race of the radial bearing 24 provided between the rotor head 38 and the casing main body 12, the adjustment of the position of the output shaft 32 is hindered. I can't.
[0061]
When the piston 42 is urged in the direction of being pushed out of the cylinder sleeve 41 by the pressure of the high-temperature and high-pressure steam supplied to the expansion chamber 43, the pressing force of the piston 42 is reduced by the swash plate 31, the angular bearing 30, and the swash plate holder. The outer race of the combined angular bearings 23f, 23r is pressed forward (to the right in FIG. 1) via the front cover 28 and the front cover 15, and the pressing force of the cylinder sleeve 41, which is opposite to the pressing force of the piston 42, is applied to the rotor head. The inner race of the combined angular bearings 23f and 23r is pressed rearward (to the left in FIG. 1) via the output shaft 38 and the output shaft 32. That is, the load generated by the high-temperature and high-pressure steam supplied to the expansion chamber 43 is canceled inside the combined angular bearings 23f and 23r, and is not transmitted to the casing body 12.
[0062]
The rotor 22 including the output shaft 32, the three sleeve support flanges 33, 34, 35, the rotor head 38, and the heat insulating cover 40 is made of an iron-based material having a relatively small thermal expansion. The casing 11 supporting the rotor 22 via the angular bearings 23f, 23r and the radial bearing 24 is made of an aluminum-based material having a relatively large thermal expansion. This causes a difference in the amount of thermal expansion particularly in the direction along the axis L.
[0063]
The casing 11 having a larger thermal expansion than the rotor 22 expands more than the rotor 22 at a high temperature and relatively increases in the dimension in the direction of the axis L. Is relatively reduced. At this time, since the casing 11 and the rotor 22 are positioned in the direction of the axis L via the combined angular bearings 23f and 23r, the difference in the amount of thermal expansion between the two is determined by the sliding of the rotor head 38 against the inner race of the radial bearing 24. And prevents the combined angular bearings 23f, 23r, the radial bearing 24 and the rotor 22 from being subjected to an excessive load in the direction of the axis L. As a result, not only the durability of the combined angular bearings 23f, 23r and the radial bearing 24 is improved, but also the support of the rotor 22 can be stabilized to enable smooth rotation. And the dead volume between the top of the piston 42 and the top of the piston 42 can be prevented.
[0064]
This is because if the both ends of the rotor 22 are restrained by the casing 11 so as not to move in the axial direction, the casing 11 tends to contract with respect to the rotor 22 in the direction of the axis L at low temperatures. The piston 42 whose head is in contact with the swash plate 31 supported by the swash plate holder 28 is pressed rearward, and the rotor head 38 supported by the casing 11 via the radial bearing 24 is pressed forward. This is because the piston 42 is pushed into the cylinder sleeve 41 and the dead volume is reduced. Conversely, when the temperature is high, the casing 11 tends to extend in the direction of the axis L with respect to the rotor 22, so that the piston 42 is pulled out from the inside of the cylinder sleeve 41 and the dead volume increases. An increase in the initial volume of the high-temperature and high-pressure steam in the operating state, that is, a decrease in the thermal efficiency due to a decrease in the volume ratio (expansion ratio) of the expander E occurs.
[0065]
On the other hand, in this embodiment, since the rotor 22 is supported by the casing 11 in a floating state in the direction of the axis L, the gap between the bearings of the combined angular bearings 23f and 23r and the radial bearing 24 is increased, and the preload is reduced. The fall is prevented, and the fluctuation of the dead volume due to the temperature change is prevented. Thereby, it is possible to prevent a change in the volume ratio (expansion ratio) of the expander E and secure stable performance.
[0066]
In particular, in the expander E that uses high-temperature and high-pressure steam as a working medium, the above-described effect is effectively exhibited because the temperature difference between high temperature and low temperature is large. In the vicinity of the rotary valve 71 to which the high-temperature and high-pressure steam is supplied, the temperature difference between the high temperature and the low temperature becomes large, but the rotor head 38 is moved along the axis L with respect to the radial bearing 24 disposed near the rotary valve 71. Since it is slidable in the direction, the difference in the amount of thermal expansion between the casing 11 and the rotor 22 can be absorbed without any trouble.
[0067]
Of the fixed-side valve plate 73 and the movable-side valve plate 74 of the rotary valve 71, the fixed-side valve plate 73 supported by the casing 11 is moved toward the movable-side valve plate 74 supported by the rotor 22 by a preload spring 85. Even when the positional relationship of the casing 11 and the rotor 22 in the direction of the axis L fluctuates due to a temperature change, the sliding surface 77 of the fixed-side valve plate 73 and the movable-side valve plate 74 is urged by the elastic force. There is no fear that the sealing performance of the device will be impaired. On the contrary, since an excessive load is prevented from acting on the combined angular bearings 23f, 23r and the radial bearing 24 and the rotating surface of the rotor 22 is stabilized, the sealing performance of the sliding surface 77 is improved and the amount of steam leakage is increased. Can be reduced.
[0068]
Next, a second embodiment of the present invention will be described with reference to FIG.
[0069]
In the above-described first embodiment, in order to fit the annular member 104 to the outer periphery of the valve body 72, a part of the valve body 72 is separated as the cap member 102, and the annular member 104 is separated from the outer periphery of the valve body 72. Then, the cap member 102 is connected to the valve body 72.
[0070]
In the second embodiment, the valve body 72 and the cap member 102 are formed as a single member, and the annular member 104 is divided into two parts at the centers of the projections 104a and 104b to enable assembly. The split projection 104a is integrally locked by a pin 105 passing through the pin holes 104d, 104d, and the split projection 104b is integrally locked by a pin 106 passing through the pin holes 104e, 104e. The projections 104a, 104b engage with the guide grooves 18c, 18c of the rear cover 18, so that the pins 105, 106 do not fall out of the pin holes 104d, 104d, 104e, 104e.
[0071]
Thus, according to the second embodiment, the same operation and effect as those of the first embodiment can be achieved.
[0072]
The embodiments of the present invention have been described above. However, various design changes can be made in the present invention without departing from the gist thereof.
[0073]
For example, the rotary fluid machine of the present invention is not limited to the expander E, but can be applied to a compressor, a hydraulic pump, a hydraulic motor, and the like.
[0074]
In addition, the expander E of the embodiment includes the axial piston cylinder group 56 as an operating unit, but the structure of the operating unit is not limited thereto.
[0075]
【The invention's effect】
As described above, according to the first aspect of the present invention, two projections are provided at both ends in the first diametrical direction of the annular member loosely fitted to the outer periphery of the valve body of the rotary valve of the rotary fluid machine. Since the projections are slidably engaged with the guide grooves formed in the casing in the axial direction, the valve body is moved in the axial direction so that the sliding surfaces of the fixed valve plate and the movable valve plate are in close contact with each other. When the two members are urged, the two members receive the sliding resistance evenly from the guide groove of the casing, thereby preventing the annular member from tilting from a plane perpendicular to the axis. Even if the annular member is inclined due to a difference in sliding resistance that the two projections receive from the guide groove, the valve body is pivotally supported on the annular member via a support shaft arranged in the second diametrical direction. As a result, the valve main body is reliably prevented from tilting with respect to the axis L, the followability of the sliding surface is ensured, the leakage of the working medium is prevented, and the uneven wear of the sliding surface is suppressed. be able to.
[0076]
According to the second aspect of the present invention, the valve body can freely move in a plane perpendicular to the axis with respect to the casing by the action of the Oldham coupling formed by the annular member and the support shaft. . Therefore, even if the valve body is inclined with respect to the axis, the valve body is free to move in a plane perpendicular to the axis, thereby preventing the occurrence of stiffness between the casing and the casing. Surface followability can be ensured.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of an expander. FIG. 2 is a sectional view taken along line 2-2 of FIG. 1. FIG. 3 is a view taken along line 3-3 of FIG. 1. FIG. 5 is an enlarged view of part 5 of FIG. 1 FIG. 6 is an exploded perspective view of the rotor FIG. 7 is a sectional view taken along line 7-7 of FIG. 4 FIG. 8 is a sectional view taken along line 8-8 of FIG. FIG. 10 is a sectional view taken along line 10-10 of FIG. 5. FIG. 11 is a sectional view taken along line 11-11 of FIG. 5. FIG. 12 is a sectional view taken along line 12-12 of FIG. FIG. 14 is a view in the direction of arrow 14 in FIG. 13. FIG. 15 is a view in the direction of arrow 15 in FIG. 13. FIG. 16 is an exploded perspective view of the Oldham coupling. FIG. Exploded perspective view of the Oldham coupling [Explanation of symbols]
11 casing 18c guide groove 22 rotor 56 axial piston cylinder group (operating part)
71 Rotary valve 72 Valve main body part 73 Fixed side valve plate 74 Movable side valve plate 77 Sliding surface 103 Support shaft 104 Annular member 104a Projection 104b Projection L Axis line XX First diameter direction YY Second diameter direction

Claims (2)

A casing (11);
A rotor (22) rotatably supported by the casing (11);
An operating part (56) provided on the rotor (22);
A rotary valve (71) provided between the casing (11) and the rotor (22) to control the supply and discharge of the working medium to and from the working portion (56);
The rotary valve (71) is fixed to a movable valve plate (74) provided on the rotor (22) and to the casing (11) so as to be non-rotatable and movable in the axis (L) direction of the rotor (22). In a rotary fluid machine, a fixed side valve plate (73) provided on a valve body (72) is brought into contact with a sliding surface (77) orthogonal to the axis (L).
Two protrusions (104a, 104b) projecting from the first diametrical ends (XX) of the annular member (104) loosely fitted to the outer periphery of the valve body (72) are attached to the casing (11). The formed guide groove (18c) is slidably engaged in the direction of the axis (L), and is arranged in a second diameter direction (Y-Y) orthogonal to the first diameter direction (XX). A rotary fluid machine characterized in that a valve body (72) is pivotally supported on an annular member (104) via a support shaft (103) so as to be swingable. The two projections (104a, 104b) of the annular member (104) are slidable in the first diametrical direction (XX) with respect to the guide groove (18c) of the casing (11), and the valve body portion The rotary fluid machine according to claim 1, characterized in that the (72) is slidable in the second diametrical direction (Y-Y) along the support shaft (103).

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