JP2005171836A - Fluid machinery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent imbalance in rotational balance of a rotary body 20, by maintaining the rotational balance of the rotary body 20 during operation of fluid machinery. <P>SOLUTION: In a compressor 10 as fluid machinery, the rotary body 20 is provided with a balance weight 60. A drive shaft 25 and a rotor 17 of an electric motor 15 constitute the rotary body 20. The drive shaft 25 has an eccentric part 27 engaged with a piston 33 of a compression mechanism 30. The balance weight 60 is disposed on an upper end face of the rotor 17. When a deformable member 70 of the balance weight 60 is extended/contracted, a weight member 61 moves to change a gravity position of the balance weight 60, and thereby the rotational balance of the rotor 17 is adjusted. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a fluid machine including a rotating body that rotates during operation.

  2. Description of the Related Art Conventionally, a fluid machine is known in which the volume of a fluid chamber through which a fluid enters and exits changes as the rotating body rotates. Patent Document 1 and Non-Patent Document 1 describe a rolling piston type rotary compressor which is a kind of this fluid machine. In a rotary compressor, a thick cylindrical piston (roller) is accommodated in a cylinder, and a fluid chamber is formed between the piston and the cylinder. A drive shaft is engaged with the piston, and a rotor of the electric motor is fixed to the drive shaft. When the electric motor is energized, the piston engaged with the drive shaft moves eccentrically in the cylinder, and the fluid is sucked into the fluid chamber and compressed.

In the above rotary compressor, an eccentric portion that engages with the piston is formed on the drive shaft. For this reason, if the drive shaft and the rotor are simply connected, the rotation body composed of the drive shaft and the rotor cannot be balanced and the rotation body cannot be smoothly rotated. Therefore, as described in Patent Document 1 and Non-Patent Document 1, it is generally performed to balance the rotation of the rotating body by attaching a balance weight to the rotating body.
Japanese Patent Laid-Open No. 10-169580 (FIG. 11) Edited by Japan Refrigeration Association "Refrigeration and Air Conditioning Handbook New Edition 5th Edition" Volume 2 Equipment, June 25, 1993, p. 30, Fig. 1. 1.29

  However, even if the rotational balance of the rotating body alone is perfectly maintained, the rotational balance of the rotating body may be lost during the operation of the fluid machine.

  For example, since there is a limit to the accuracy when assembling a fluid machine, the center axis of the rotor itself and the center of rotation of the actual rotor must be completely coincident when the rotor is actually installed in the fluid machine. Is rare. For this reason, during operation of the fluid machine, the rotating body rotates in a state in which the rotational balance is lost, which may cause vibration and noise, and may cause troubles such as bearing seizure.

  Further, during operation of the fluid machine, centrifugal force or a load from the fluid in the fluid chamber acts on the rotating body, and the rotating body is deformed. When the operating state of the fluid machine changes, the amount of deformation of the rotating body due to centrifugal force or the like also changes. For this reason, when the operating state of the fluid machine changes, the rotational balance of the rotating body is lost, which may cause vibration, noise, or bearing seizure.

  The present invention has been made in view of such points, and the object of the present invention is to keep the rotating body in a balanced state during operation of the fluid machine, and to cause the rotational balance of the rotating body to be lost. The problem is to solve the problem.

  According to a first aspect of the present invention, there is provided a main body mechanism (30) having a movable member (33) that performs an eccentric motion and a fluid chamber (40) through which a fluid enters and exits as the movable member (33) moves, and the main body mechanism ( It is intended for a fluid machine including a rotating body (20) having a shaft (25) engaged with a movable member (33) of 30). The balance weight (60) is composed of a deformable member (70) that is deformed by an external input and is configured in whole or in part to be attached to the rotating body (20). Can be changed by the deformation of the deformable member (70).

  According to a second aspect of the present invention, in the first aspect, the balance weight (60) is partially configured by the deformable member (70), and the weight member (70) moves with the deformation of the deformable member (70). 61).

  In a third aspect based on the first aspect, the deformable member (70) is configured such that the distance between the rotation center axis of the rotating rotating body (20) and the center of gravity of the balance weight (60) is kept constant. It will be transformed into.

  According to a fourth aspect, in the first aspect, the deformation amount of the deformation member (70) is set corresponding to the rotation speed of the rotating body (20).

  According to a fifth invention, in the first invention, the deformation amount of the deformation member (70) is set corresponding to the state of the fluid entering and exiting the fluid chamber (40).

  In a sixth aspect of the present invention based on the first aspect, the electric motor (15) for driving the movable member (33) of the main body mechanism (30) is provided, while the shaft (25) has a portion near one end of the main body (30). A portion near the other end is rotatably supported by the mechanism (30) and connected to the rotor (17) of the electric motor (15). The rotating body (20) includes the shaft (25) and the electric motor (15 The balance weight (60) is disposed on the end surface of the rotor (17) opposite to the main body mechanism (30).

  In a seventh aspect based on the first aspect, the deformable member (70) is constituted by a polymer actuator that deforms when a voltage as an external input is applied.

  In an eighth aspect based on the seventh aspect, the rotating body (20) is provided with a conductive member (80) connected to the deformable member (70) and generating electromotive force by electromagnetic induction. .

  According to a ninth invention, in the first invention, there is provided a detecting means for detecting a degree of rotation balance of the rotating body (20), and the deformation member (70) is detected in accordance with a detection value obtained by the detecting means. The amount of deformation is adjusted.

-Action-
In the first invention, the shaft (25) of the rotating body (20) is engaged with the movable member (33) of the main body mechanism (30). In the main body mechanism (30), fluid enters and exits the fluid chamber (40) as the movable member (33) moves eccentrically. For example, when fluid compression is performed in the main body mechanism (30), when the movable member (33) moves eccentrically, a low-pressure fluid is sucked into the fluid chamber (40) and compressed, and further the compressed fluid Is discharged from the fluid chamber (40). On the other hand, when the fluid is expanded in the main body mechanism (30), the movable member (33) is driven by the expansion of the high-pressure fluid that has flowed into the fluid chamber (40). 40).

  In the present invention, the rotating body (20) is provided with a balance weight (60). The balance weight (60) is entirely or partially constituted by the deformable member (70). The deformable member (70) is configured to be deformed by an external input such as a signal input. When the deformable member (70) is deformed, the position of the center of gravity of the balance weight (60) changes, and the rotation balance of the rotating body (20) changes accordingly.

  In the second aspect of the invention, the weight member (61) is provided on the balance weight (60) in addition to the deformable member (70), and a part of the balance weight (60) is constituted by the deformable member (70). When the deformable member (70) is deformed, the weight member (61) moves, and the position of the center of gravity of the entire balance weight (60) changes.

  In the third aspect, the deformation member (70) is deformed, so that the distance between the rotation center axis of the rotating body (20) and the center of gravity of the balance weight (60) is kept constant. In other words, even when the rotating rotator (20) is elastically deformed by a load such as centrifugal force, the distance between the rotation center axis of the rotator (20) and the center of gravity of the balance weight (60) is kept constant. The “rotation center axis” here means not the geometric center axis of the rotator (20) but the center axis of the rotational motion of the rotator (20) during rotation.

  In the fourth aspect of the invention, the deformation amount of the deformable member (70) is set according to the rotational speed of the rotating body (20). When the rotational speed of the rotating body (20) fluctuates, the centrifugal force acting on the rotating body (20) changes, and the amount of deformation of the rotating body (20) due to this centrifugal force changes. Therefore, in the present invention, the deformation amount of the deformable member (70) is set according to the rotational speed of the rotating body (20), and the center of gravity position of the balance weight (60) is adjusted according to the deformation amount of the rotating body (20). To do.

  In the fifth aspect, the deformation amount of the deformation member (70) is set according to the state of the fluid flowing into or out of the fluid chamber (40). For example, when the pressure of the fluid entering and exiting the fluid chamber (40) varies, the load exerted on the shaft (25) by the fluid in the fluid chamber (40) via the movable member (33) changes. And if the load which acts on a shaft (25) changes, the deformation amount of the rotary body (20) resulting from this load will change. Therefore, in the present invention, the deformation amount of the deformation member (70) is set according to the state of the fluid entering and exiting the fluid chamber (40), and the center of gravity of the balance weight (60) is determined according to the deformation amount of the rotating body (20). Adjust the position.

  In the sixth invention, the electric motor (15) is provided in the fluid machine. In this fluid machine, the shaft (25) has a portion near one end thereof supported by the main body mechanism (30) and a portion near the other end connected to the rotor (17) of the electric motor (15). During operation of the fluid machine, the rotating body (20) composed of the shaft (25) and the rotor (17) of the electric motor (15) rotates, and the movable member (33) of the main body mechanism (30) is driven. The In the rotating body (20) of the fluid machine, the balance weight (60), which is entirely or partially constituted by the deformable member (70), is provided on the end surface of the rotor (17) opposite to the main body mechanism (30). It is done. That is, this balance weight (60) is installed on the end face on the side away from the main body mechanism (30) that supports the shaft (25) of the rotating body (20) among the two end faces of the rotor (17).

  In the seventh invention, the deformable member (70) is constituted by the polymer actuator. When a voltage as an external input is applied to the deformable member (70), the deformable member (70) is deformed and the center of gravity of the balance weight (60) moves.

  In the eighth aspect of the invention, the conductive member (80) is connected to the deformable member (70) formed of the polymer actuator. When the conductive member (80) provided on the rotating body (20) moves in the magnetic field, an electromotive force is generated in the conductive member (80) by electromagnetic induction, and the deformable member (70) connected to the conductive member (80). A voltage is applied as an external input.

  In the ninth invention, a detecting means is provided. This detection means detects the degree of the rotational balance of the rotating rotating body (20). In the present invention, the amount of deformation of the deformable member (70) is adjusted according to the detection value obtained by the detecting means, that is, the degree of disruption of the rotational balance of the rotating body (20).

  In the present invention, the entire or part of the balance weight (60) is composed of the deformable member (70), and the position of the center of gravity of the balance weight (60) changes as the deformable member (70) is deformed. For this reason, even after the fluid machine is assembled or during operation of the fluid machine, the deformable member (70) can be deformed to change the position of the center of gravity of the balance weight (60). ) Rotation balance can be changed. Even when there is an error during assembly or the rotating body (20) is deformed during operation, it is possible to keep the rotating body (20) in a balanced state by deforming the deformable member (70). Become.

  Therefore, according to the present invention, it is possible to reduce vibration and noise caused by the rotation balance of the rotating body (20) being lost. In addition, according to the present invention, it is possible to improve the reliability of the fluid machine by avoiding troubles such as bearing seizure due to the loss of the rotational balance of the rotating body (20).

  In the third aspect of the invention, the distance between the rotation center axis of the rotating body (20) and the center of gravity of the balance weight (60) is kept constant by the deformation of the deformation member (70). Here, when the operating state of the fluid machine changes, the load acting on the rotating body (20) also changes, and the amount of deformation of the rotating body (20) due to this load also changes. Therefore, if the position of the center of gravity of the balance weight (60) relative to the rotating body (20) is fixed, the rotation center axis of the rotating body (20) and the balance weight (60) There is a possibility that the distance of the center of gravity changes and the rotational balance of the rotating body (20) is lost. On the other hand, in this invention, even if the deformation amount of the rotating body (20) changes due to the deformation of the deformable member (70), the distance between the rotation center axis of the rotating body (20) and the center of gravity of the balance weight (60) Is held constant. Therefore, according to the present invention, even when the operating state of the fluid machine changes and the deformation amount of the rotating body (20) changes, the rotational balance of the rotating body (20) can be reliably maintained.

  In the fourth aspect of the invention, the deformation amount of the deformation member (70) is set according to the rotational speed of the rotating body (20), and the center of gravity position of the balance weight (60) is set according to the deformation amount of the rotating body (20). It is adjusting. Here, when the rotational speed of the rotating body (20) varies and the amount of deformation of the rotating body (20) due to centrifugal force changes, the rotational balance of the rotating body (20) may be lost. On the other hand, according to the present invention, it becomes possible to adjust the position of the center of gravity of the balance weight (60) according to the amount of deformation of the rotating body (20) caused by the centrifugal force, and the rotational speed of the rotating body (20) is reduced. Even if it fluctuates, the rotational balance of the rotating body (20) can be reliably maintained.

  According to the fifth aspect, the deformation amount of the deformation member (70) is set according to the state of the fluid entering and exiting the fluid chamber (40), and the balance weight (60) according to the deformation amount of the rotating body (20). ) Is adjusted. Here, when the load acting on the shaft (25) changes due to a change in the state of the fluid entering and exiting the fluid chamber (40), the amount of deformation of the rotating body (20) due to the load changes and the rotating body ( 20) The rotation balance may be lost. On the other hand, according to the present invention, it becomes possible to adjust the position of the center of gravity of the balance weight (60) according to the amount of deformation of the rotating body (20) due to the load on the shaft (25), and the fluid chamber (40 The rotational balance of the rotating body (20) can be reliably maintained even if the state of the fluid entering and exiting the fluctuates.

  In the sixth aspect of the invention, the balance weight (60), which is entirely or partly composed of the deformable member (70), is used for the shaft (25) of the rotating body (20) of the pair of end faces of the rotor (17). It is installed on the end face on the side away from the supporting main body mechanism (30). Here, as described above, a centrifugal force acts on the rotating rotator (20), and the rotator (20) is deformed by the centrifugal force. At that time, in the rotating body (20), the amount of displacement increases as the position is away from the main body mechanism (30) supporting the shaft (25). On the other hand, in the present invention, the position of the center of gravity of the balance weight (60) provided in the part of the rotating body (20) that is away from the main body mechanism (30) can be changed. This makes it possible to change the position of the center of gravity of the balance weight (60) at the position of the rotating body (20) where the displacement during rotation is the largest, ensuring the rotational balance of the rotating body (20) during rotation. Can be taken.

  In the seventh aspect of the invention, the deformable member (70) is composed of a polymer actuator. Therefore, according to the present invention, the balance weight (60) having a variable center of gravity can be realized with a simple structure.

  In the eighth aspect of the invention, the conductive member (80) is connected to the deformable member (70), and an electromotive force is generated in the conductive member (80) by electromagnetic induction, whereby the voltage as an external input is applied to the deformable member (70). Is applied. Therefore, according to the present invention, the voltage as an external input from the outside of the rotating body (20) without contacting the deforming member (70) with respect to the deforming member (70) provided on the rotating rotating body (20). Can be given.

  In the ninth aspect of the present invention, the degree of rotation balance of the rotating body (20) is detected by the detecting means, and the deformation amount of the deforming member (70) is adjusted according to the detection value obtained by the detecting means. . Accordingly, the center of gravity of the balance weight (60) can be set to an optimum position, and the rotating body (20) can be reliably held in a state in which the rotation balance is achieved.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

Embodiment 1 of the Invention
A first embodiment of the present invention will be described. This embodiment is the compressor (10) comprised by the fluid machine which concerns on this invention. The compressor (10) is provided in the refrigerant circuit of the refrigeration apparatus and used to compress the refrigerant.

  As shown in FIG. 1, the compressor (10) of the present embodiment is a so-called oscillating piston type rotary compressor. The compressor (10) is configured as a so-called hermetic type. Specifically, the compressor (10) includes a casing (11) formed in a cylindrical sealed container shape that is long in the vertical direction. The casing (11) contains a compression mechanism (30) as a main body mechanism, a drive shaft (25) as a shaft, and an electric motor (15). In the casing (11), the compression mechanism (30) is disposed below the electric motor (15).

  A terminal (12) and a discharge pipe (13) are attached to the top of the casing (11). The terminal (12) is for supplying electric power to the electric motor (15). On the other hand, the discharge pipe (13) passes through the casing (11), and one end thereof opens into a space in the casing (11).

  As shown in FIG. 2, the compression mechanism (30) includes a cylinder (31), a front head (50), a rear head (55), and a piston (33). The front head (50) is disposed above the cylinder (31), and the rear head (55) is disposed below the cylinder (31). The cylinder (31) is sandwiched from above and below by the front head (50) and the rear head (55).

  The cylinder (31) is formed in a thick and short cylindrical shape. On the other hand, the piston (33) is formed in a cylindrical shape having substantially the same height as the cylinder (31). The piston (33) is engaged with the eccentric part (27) of the drive shaft (25) and constitutes a movable member. The outer peripheral surface of the piston (33) is in sliding contact with the inner peripheral surface of the cylinder (31). By accommodating the piston (33) in the cylinder (31), a compression chamber (40) which is a fluid chamber is formed in the cylinder (31).

  The piston (33) is integrally provided with a blade (34). The blade (34) is formed in a plate shape and projects outward from the outer peripheral surface of the piston (33). The compression chamber (40) sandwiched between the inner peripheral surface of the cylinder (31) and the outer peripheral surface of the piston (33) is partitioned into a high pressure side (41) and a low pressure side (42) by the blade (34). In FIG. 2, the right side of the blade (34) is the low pressure side (42) of the compression chamber (40), and the left side of the blade (34) is the high pressure side (41) of the compression chamber (40).

  The cylinder (31) is provided with a pair of bushes (35). Each bush (35) is formed in a half-moon shape. The bush (35) is installed with the blade (34) sandwiched therebetween, and slides on the side surface of the blade (34). The bush (35) is rotatable with respect to the cylinder (31) with the blade (34) interposed therebetween.

  The cylinder (31) is formed with a suction port (32). One end of the suction port (32) opens to the inner peripheral surface of the cylinder (31) and communicates with the low pressure side (42) of the compression chamber (40). A suction pipe (14) is inserted into the other end of the suction port (32). The suction pipe (14) extends through the body of the casing (11) to the outside of the casing (11).

  As shown in FIG. 1, the front head (50) is formed in a substantially flat plate shape, and its lower surface is in close contact with the upper surface of the cylinder (31). A cylindrical main bearing portion (51) is formed at the center of the front head (50) so as to protrude upward. The main bearing portion (51) constitutes a sliding bearing for supporting the drive shaft (25). The front head (50) is formed with a discharge port (45) communicating with the high pressure side (41) of the compression chamber (40). The front head (50) is provided with a discharge valve (46) constituted by a reed valve so as to cover the discharge port (45) (see FIG. 2). A muffler (47) for reducing the pulsation of the discharge gas is attached to the upper surface of the front head (50).

  The rear head (55) is generally formed in a flat plate shape, and its upper surface is in close contact with the lower surface of the cylinder (31). A cylindrical auxiliary bearing portion (56) is formed at the center of the rear head (55) so as to protrude downward. The sub bearing portion (56) constitutes a sliding bearing for supporting the drive shaft (25).

  The electric motor (15) includes a stator (16) and a rotor (17). The stator (16) is fixed to the body of the casing (11) by shrink fitting or the like. Although not shown, the stator (16) is electrically connected to a terminal of the terminal (12) via a lead wire (not shown). On the other hand, the rotor (17) is fixed to the drive shaft (25).

  The drive shaft (25) includes a main shaft portion (26) and an eccentric portion (27), and is provided in a vertically extending posture. The eccentric portion (27) is provided in a portion near the lower end of the drive shaft (25). The eccentric portion (27) is formed with a larger diameter than the main shaft portion (26), and the shaft center is eccentric with respect to the shaft center of the main shaft portion (26). Moreover, the eccentric part (27) penetrates the piston (33), and the outer peripheral surface thereof is in sliding contact with the inner peripheral surface of the piston (33). The drive shaft (25) is rotatably supported at its lower end by the compression mechanism (30). Specifically, the portion immediately above the eccentric portion (27) of the main shaft portion (26) is supported by the main bearing portion (51), and the portion immediately below the eccentric portion (27) is the sub-bearing portion (56). ).

  The rotor (17) of the electric motor (15) is attached to a portion near the upper end of the drive shaft (25). The rotor (17) forms a rotating body (20) together with the drive shaft (25). An upper balance weight (60) and a lower balance weight (65) are attached to the rotor (17). The upper balance weight (60) is disposed on the upper end surface of the rotor (17), that is, the end surface opposite to the compression mechanism (30). On the other hand, the lower balance weight (65) is disposed on the lower end surface of the rotor (17), that is, the end surface near the compression mechanism (30). The lower balance weight (65) is entirely made of metal and is fixed to the rotor (17). The lower balance weight (65) is provided at a position offset to the opposite side of the eccentric direction of the eccentric portion (27) with respect to the main shaft portion (26).

  As shown in FIG. 3, the upper balance weight (60) includes a weight member (61) and a deformable member (70). The weight member (61) is a metal member and is provided at a position offset to the same side as the eccentric direction of the eccentric portion (27) with respect to the main shaft portion (26). On the other hand, the deformable member (70) is a polymer actuator composed of a conductive polymer element, and expands and contracts when a voltage is applied. The deformable member (70) has one end in the expansion / contraction direction joined to the weight member (61) and the other end joined to the rotor (17). When the deformable member (70) is deformed, the weight member (61) moves accordingly, and the relative position of the center of gravity of the upper balance weight (60) with respect to the rotor (17) changes.

  As shown in FIG. 4, the deformable member (70) includes a first electrode (71), a second electrode (72), a polymer material (73), and an electrolytic solution (74). The polymer material (73) is made of polyaniline, for example, and is disposed so as to be in contact with the first electrode (71). On the other hand, the electrolytic solution (74) is disposed so as to be in contact with both the polymer membrane and the second electrode (72).

  When a voltage is applied so that the first electrode (71) serves as an anode and the second electrode (72) serves as a cathode, the anion in the electrolyte solution (74) becomes polymer material (73) in the deformable member (70). The polymer material (73) is swollen and the length of the deformable member (70) is extended. Conversely, when a voltage is applied so that the first electrode (71) serves as a cathode and the second electrode (72) serves as an anode, the negative ions incorporated into the polymer material (73) in the deformable member (70). Is released into the electrolytic solution (74), the polymer material (73) contracts, and the length of the deformable member (70) decreases. The deformable member (70) maintains the length immediately before the voltage application is stopped even after the voltage application is stopped after the voltage is applied to change the length.

  As shown in FIGS. 3 and 4, the induction coil (80) is connected to the deformable member (70). Specifically, the induction coil (80) has one end connected to the first electrode (71) and the other end connected to the second electrode (72). The induction coil (80) constitutes a conductive member that generates an electromotive force by electromagnetic induction, and is attached to the upper end surface of the rotor (17) together with the upper balance weight (60).

-Driving action-
The operation of the compressor (10) will be described.

  When electric power is supplied to the electric motor (15) via the terminal (12), the drive shaft (25) is rotationally driven by the electric motor (15). In FIG. 2, when the drive shaft (25) rotates in the clockwise direction, the piston (33) engaged with the eccentric portion (27) of the drive shaft (25) has an outer peripheral surface that is the same as the inner peripheral surface of the cylinder (31). Move in sliding contact. At that time, the piston (33) integrally formed with the blade (34) moves so as to swing while slidingly contacting the cylinder (31).

  When the piston (33) moves in the cylinder (31), the volume of the low pressure side (42) gradually increases in the compression chamber (40), and the gas refrigerant passes through the suction port (32) and flows into the compression chamber (40). Sucked into the low pressure side (42). At the same time, the volume of the high pressure side (41) of the compression chamber (40) gradually decreases, and the gas refrigerant confined in the high pressure side (41) of the compression chamber (40) is compressed. When the internal pressure on the high pressure side (41) of the compression chamber (40) gradually increases, the discharge valve (46) is eventually pushed up by the gas refrigerant, and the compressed gas refrigerant passes through the discharge port (45) and flows into the muffler (47). It is discharged inside (see FIG. 1). Thereafter, the compressed gas refrigerant is sent out of the casing (11) through the discharge pipe (13).

-Control for upper balance weight-
In the compressor (10), the deformation amount of the deformable member (70) of the upper balance weight (60) is adjusted according to the rotational speed of the rotating body (20). Here, adjustment of the deformation amount in the deformation member (70) will be described with reference to FIG. In the figure, the rotation center axis means the center axis of the rotary motion of the rotating body (20).

  When the rotational speed of the rotating body (20) is low, the centrifugal force acting on the rotating body (20) is small, and the amount of deformation of the rotating body (20) due to the centrifugal force is negligibly small. In this state, it is assumed that the rotation balance of the rotating body (20) is balanced, and the distance between the center of gravity G of the upper balance weight (60) and the rotation center axis of the rotating body (20) is L.

  When the rotational speed of the rotating body (20) becomes high, the centrifugal force acting on the rotating body (20) increases, and the amount of deformation of the rotating body (20) due to the centrifugal force increases. In this rotating body (20), only the portion near the lower end of the drive shaft (25) is supported by the main bearing portion (51) and the auxiliary bearing portion (56). For this reason, in the rotating body (20), the displacement of the rotating body (20) farthest from the compression mechanism (30), that is, the upper end portion of the rotor (17) becomes the largest.

  If the weight member (61) is not moved while the rotational speed of the rotating body (20) is high, the distance between the center of gravity G of the upper balance weight (60) and the rotation center axis of the rotating body (20) is L. Longer and the rotational balance of the rotating body (20) is lost. Therefore, as the rotational speed of the rotating body (20) increases, the deformable member (70) is deformed so that its entire length is shortened.

  Specifically, a magnetic field is generated around the induction coil (80) that rotates with the rotating body (20), an electromotive force is generated in the induction coil (80) by electromagnetic induction, and a voltage is applied to the deformable member (70). To do. At that time, a voltage is applied to the deformable member (70) such that the second electrode (72) of the deformable member (70) serves as an anode and the first electrode (71) serves as a cathode. When the voltage is applied in this manner, the deformable member (70) contracts (see FIG. 4), and the weight member (61) is drawn toward the rotation center axis of the rotating body (20). At this time, the deformable member (70) contracts by a predetermined length so that the distance between the center of gravity G of the upper balance weight (60) and the rotation center axis of the rotating body (20) is maintained at L.

  On the other hand, when the rotational speed of the rotating body (20) decreases from this state, the magnetic field around the induction coil (80) is changed, and this time, the first electrode (71) of the deformable member (70) becomes the anode and becomes the second. A voltage is applied so that the electrode (72) becomes a cathode. When the voltage is applied in this manner, the deformable member (70) extends (see FIG. 4), and the weight member (61) is pulled away from the rotation center axis of the rotating body (20). At this time, the deformable member (70) extends by a predetermined length so that the distance between the center of gravity G of the upper balance weight (60) and the rotation center axis of the rotating body (20) is maintained at L.

  Thus, in the compressor (10), the deformable member (70) of the upper balance weight (60) expands and contracts in accordance with the rotational speed of the rotating body (20), regardless of the rotating speed of the rotating body (20). The distance between the center of gravity G of the upper balance weight (60) and the rotation center axis of the rotating body (20) is maintained at L. That is, even if the rotational speed of the rotating body (20) changes, the rotating body (20) is always kept in a state of rotational balance.

-Effect of Embodiment 1-
In the present embodiment, the upper balance weight (60) is composed of the weight member (61) and the deformable member (70), and the upper member is moved by expanding and contracting the deformable member (70) to move the weight member (61). The center of gravity of the weight (60) is changed. In this embodiment, the deformable member (70) is expanded and contracted according to the rotational speed of the rotating body (20), and the distance between the rotation center axis of the rotating body (20) and the center of gravity of the upper balance weight (60) is made constant. keeping. For this reason, even if the rotational speed of the rotating body (20) changes and the amount of deformation of the rotating body (20) due to centrifugal force changes, the rotation center axis of the rotating body (20) and the upper balance weight (60) The distance of the center of gravity is kept constant, and the rotating body (20) is always kept in a balanced state.

  Therefore, according to the present embodiment, it is possible to reduce vibration and noise caused by the rotation balance of the rotating body (20) being lost. In addition, according to the present embodiment, troubles such as bearing seizure due to the rotation balance of the rotating body (20) can be avoided, and the reliability of the compressor (10) can be improved.

  In the present embodiment, the upper balance weight (60) is provided on the upper end surface of the rotor (17) far from the compression mechanism (30). Here, as described above, in the rotating rotator (20), the amount of displacement increases with increasing distance from the compression mechanism (30) that supports the drive shaft (25). On the other hand, in the present embodiment, the position of the center of gravity of the upper balance weight (60) provided in the part of the rotating body (20) that is away from the compression mechanism (30) can be changed. For this reason, it becomes possible to change the center of gravity position of the upper balance weight (60) at the location where the amount of displacement during rotation is the largest in the rotating body (20), and the rotational balance of the rotating body (20) during rotation can be adjusted. It can be taken reliably.

  In the present embodiment, the deformable member (70) is composed of a polymer actuator. As described above, this polymer actuator expands and contracts using a chemical change in the polymer material (73), and has a simple configuration and high reliability compared to a mechanical actuator. Therefore, according to this embodiment, the center of gravity of the upper balance weight (60) can be changed, and the compressor (10) with a simple configuration and high reliability can be realized.

<< Embodiment 2 of the Invention >>
A second embodiment of the present invention will be described. In the present embodiment, the configuration of the upper balance weight (60) in the compressor (10) of the first embodiment is changed. Here, the difference between the present embodiment and the first embodiment will be described.

  As shown in FIGS. 6 and 7, the upper balance weight (60) includes a weight member (61) and a deformable member (70), and the weight member (61) is made of metal. This is the same as in the first embodiment. The deformable member (70) of the present embodiment is a polymer actuator constituted by an ion conductive polymer element, and is bent when a voltage is applied. The deformable member (70) has a longitudinal center portion joined to the weight member (61) and both longitudinal ends joined to the rotor (17). When the deformable member (70) is deformed, the weight member (61) moves accordingly, and the relative position of the center of gravity of the upper balance weight (60) with respect to the rotor (17) changes.

  As shown in FIG. 7, the deformable member (70) includes a first electrode (71), a second electrode (72), and a hydrous polymer electrolyte (75). The hydrous polymer electrolyte (75) is sandwiched between the first electrode (71) and the second electrode (72) and is in contact with both the first electrode (71) and the second electrode (72). The weight member (61) is joined to the first electrode (71) side of the deformable member (70). As in the first embodiment, the induction coil (80) is connected to the first electrode (71) and the second electrode (72) of the deformable member (70).

  When voltage is applied so that the first electrode (71) becomes the anode and the second electrode (72) becomes the cathode, the cation in the hydrous polymer electrolyte (75) is accompanied by water in the deformable member (70). It moves to the second electrode (72) side, and water is unevenly distributed on the second electrode (72) side in the hydrous polymer electrolyte (75). For this reason, in the hydrated polymer electrolyte (75), the portion near the second electrode (72) expands and the portion near the first electrode (71) contracts.

  Conversely, when a voltage is applied so that the first electrode (71) serves as a cathode and the second electrode (72) serves as an anode, the cation in the hydrous polymer electrolyte (75) becomes water in the deformable member (70). In the hydrated polymer electrolyte (75), water is unevenly distributed on the first electrode (71) side. For this reason, the water-containing polymer electrolyte (75) is in a state where the portion near the first electrode (71) is expanded and the portion near the second electrode (72) is contracted.

  Further, the deformable member (70) retains the shape immediately before the voltage application is stopped even after the voltage application is stopped after the voltage is applied and bent.

  Also in the present embodiment, as in the first embodiment, the deformation amount of the deformable member (70) of the upper balance weight (60) is adjusted according to the rotational speed of the rotating body (20). The deforming member (70) is deformed so that the distance between the center of gravity of the upper balance weight (60) and the rotation center axis of the rotating body (20) is kept constant regardless of the rotation speed of the rotating body (20). To do.

  Specifically, when it is desired to draw the weight member (61) toward the rotation center axis of the rotating body (20), the second electrode (72) of the deformable member (70) serves as the anode and serves as the first electrode (71). A voltage is applied to the deformable member (70) so that becomes a cathode. When the voltage is applied in this way, the deformable member (70) is bent toward the first electrode (71) (see FIG. 7), and the weight member (61) is drawn toward the rotation center axis side of the rotating body (20) to be The center of gravity of the balance weight (60) approaches the rotation center axis of the rotating body (20). Conversely, when it is desired to separate the weight member (61) from the rotation center axis of the rotating body (20), the first electrode (71) of the deformable member (70) serves as the anode and the second electrode (72) serves as the cathode. A voltage is applied to the deformable member (70) so that When the voltage is applied in this way, the deformable member (70) is bent toward the second electrode (72) (see FIG. 7), and the weight member (61) is separated from the rotation center axis of the rotating body (20), and the upper balance is achieved. The center of gravity of the weight (60) moves away from the rotation center axis of the rotating body (20).

<< Other Embodiments >>
In each of the above embodiments, the center of gravity of the upper balance weight (60) may be moved according to the state of the gas refrigerant entering and exiting the compression chamber (40).

  Here, when the operating state of the refrigeration apparatus provided with the compressor (10) fluctuates, the high pressure and low pressure of the refrigeration cycle change, and accordingly, the pressure of the refrigerant flowing into the compression chamber (40) and the compression chamber ( The pressure of the refrigerant discharged from 40) changes. Thus, when the pressure of the refrigerant entering and exiting the compression chamber (40) changes, the internal pressure difference between the high pressure side (41) and the low pressure side (42) in the compression chamber (40) fluctuates, and accordingly, from the piston (33) The load that the drive shaft (25) receives changes. And if the load which acts on a drive shaft (25) changes, there exists a possibility that the deformation amount of a rotary body (20) provided with a drive shaft (25) may change, and the rotation balance of a rotary body (20) may be broken. That is, even if the rotational speed of the rotating body (20) during operation of the compressor (10) is constant, the rotational balance of the rotating body (20) may be lost.

  Therefore, the deformable member (70) is deformed according to the suction pressure and discharge pressure of the compressor (10), and the center of gravity of the upper balance weight (60) is moved to maintain the rotational balance of the rotating body (20). May be.

  In each of the above embodiments, the deformable member (70) may be used to adjust the rotational balance of the rotating body (20) when the compressor (10) is assembled.

  Here, the accuracy in assembling the compressor (10) is limited, and it is inevitable that a certain amount of error occurs. For this reason, in a state where the rotating body (20) is actually incorporated in the compressor (10), the center axis of the rotating body (20) itself and the rotation center of the actual rotating body (20) are completely coincident with each other. It is rare.

  Therefore, a trial run is performed after the compressor (10) is assembled, and the deformable member (70) is deformed so that the rotating body (20) is in a balanced state of rotation so that the center of gravity of the upper balance weight (60) is set. You may make it adjust. In this way, even if there is an error when assembling the compressor (10), the rotational balance of the rotating body (20) can be ensured.

  Further, in each of the above embodiments, a detector is provided as a detecting means for detecting the degree of the rotational balance of the rotating body (20), and the deformation member (70) is based on the detection value obtained by the detector. A deformation amount may be set. In this case, as the degree of disruption of the rotational balance of the rotating body (20) detected by the detector increases, the amount of deformation of the deformable member (70) is set larger, and the amount of movement of the center of gravity position of the upper balance weight (60) Will increase.

  Examples of the detector include one that monitors the load that the main bearing portion (51) receives from the drive shaft (25) and estimates the degree of the rotational balance of the rotating body (20) from the fluctuation of the load. The Moreover, you may comprise the said detector using a deformation | transformation member (70). That is, when an external force is applied to the deformable member (70) made of the polymer actuator to cause deformation, an electromotive force is generated in the deformable member (70). Therefore, the electromotive force in the deformable member (70) that receives the centrifugal force during the rotation of the rotating body (20) is monitored, and the degree of disruption of the rotational balance of the rotating body (20) is estimated from the fluctuation of the electromotive force. A detector may be configured.

  Moreover, in each said embodiment, although the compressor (10) is comprised with the fluid machine which concerns on this invention, you may comprise an expander with the fluid machine which concerns on this invention. In this case, a high-pressure fluid is introduced into the fluid chamber of the main body mechanism. Then, the high-pressure fluid flowing into the fluid chamber expands, whereby the piston moves and the shaft is driven to rotate. That is, the internal energy of the fluid introduced into the fluid chamber is converted into the rotational power of the shaft.

  In each of the above embodiments, the present invention is applied to a swinging piston type rotary fluid machine, but instead of this, a rolling piston type rotary fluid machine in which a piston and a blade are formed separately. The present invention may be applied. The application target of the present invention is not limited to a rotary fluid machine, and the present invention may be applied to other types of fluid machines, for example, a scroll type fluid machine.

  As described above, the present invention is useful for a fluid machine in which a rotating body rotates during operation.

It is a schematic sectional drawing which shows the whole structure of the compressor in Embodiment 1. FIG. FIG. 3 is a schematic cross-sectional view showing a configuration of a compression mechanism in Embodiment 1. FIG. 3 is a schematic top view of the rotating body in the first embodiment. FIG. 3 is a schematic configuration diagram of a deformable member showing the configuration and operation of the deformable member in the first embodiment. FIG. 3 is a schematic configuration diagram of a rotator showing an operation of an upper balance weight in the first embodiment. 6 is a schematic top view of a rotating body in Embodiment 2. FIG. It is a schematic block diagram of the deformation member which shows the structure and operation | movement of a deformation member in Embodiment 2.

Explanation of symbols

(10) Compressor (fluid machine)
(15) Electric motor (17) Rotor (20) Rotating body (25) Drive shaft (shaft)
(30) Compression mechanism (main body mechanism)
(33) Piston (movable member)
(40) Compression chamber (fluid chamber)
(60) Upper balance weight (61) Weight member (70) Deformation member (80) Induction coil (conductive member)

Claims (9)

A main body mechanism (30) having a movable member (33) that performs an eccentric motion and a fluid chamber (40) through which the fluid enters and exits as the movable member (33) moves;
A fluid machine comprising a rotating body (20) having a shaft (25) engaged with a movable member (33) of the main body mechanism (30),
Comprising a balance weight (60) which is entirely or partially constituted by a deformable member (70) deformed by an external input and is attached to the rotating body (20);
The balance weight (60) is a fluid machine in which the position of the center of gravity can be changed by the deformation of the deformation member (70). The fluid machine according to claim 1,
The balance weight (60) is a fluid machine that includes a weight member (61) that is partially configured by the deformable member (70) and moves in accordance with the deformation of the deformable member (70). The fluid machine according to claim 1,
The deformable member (70) is a fluid machine that deforms so that the distance between the rotation center axis of the rotating rotating body (20) and the center of gravity of the balance weight (60) is kept constant. The fluid machine according to claim 1,
A fluid machine in which the amount of deformation of the deformable member (70) is set corresponding to the rotational speed of the rotating body (20). The fluid machine according to claim 1,
A fluid machine in which the deformation amount of the deformation member (70) is set in accordance with the state of the fluid entering and exiting the fluid chamber (40). The fluid machine according to claim 1,
While having an electric motor (15) for driving the movable member (33) of the main body mechanism (30),
The shaft (25) has a portion near one end rotatably supported by the main body mechanism (30) and a portion near the other end connected to the rotor (17) of the electric motor (15).
The rotating body (20) includes the shaft (25) and the rotor (17) of the electric motor (15).
The balance weight (60) is a fluid machine arranged on an end surface of the rotor (17) opposite to the main body mechanism (30). The fluid machine according to claim 1,
The deformable member (70) is a fluid machine configured by a polymer actuator that deforms when a voltage is applied as an external input. The fluid machine according to claim 7, wherein
The fluid machine in which the rotating member (20) is provided with a conductive member (80) that is connected to the deformable member (70) and generates an electromotive force by electromagnetic induction. The fluid machine according to claim 1,
Comprising a detecting means for detecting the degree of disruption of the rotational balance of the rotating body (20),
A fluid machine in which the deformation amount of the deformation member (70) is adjusted in accordance with the detection value obtained by the detection means.

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