JP5999971B2 - Scroll compressor - Google Patents

Description

  The present invention relates to a scroll compressor used for refrigeration and air conditioning applications, and more particularly to a scroll compressor having a so-called asymmetrical spiral in order to increase a stroke volume in a limited space.

  The scroll compressor includes a fixed scroll and an orbiting scroll combined so that the formed spirals mesh with each other. Then, when the orbiting scroll is swung, the volume of the compression chamber formed by each spiral is reduced, and the fluid is compressed.

  In such a scroll-type compressor, the gas load acting on the orbiting scroll is shifted from the center, so that a rotation moment for rotating the orbiting scroll is generated, and the orbiting is counteracted. An Oldham ring is often used as an anti-rotation means for regulating the scroll posture and causing a swinging motion.

  A reaction force against the rotation moment acts on the claw portion of the Oldham ring, but the magnitude depends on the rotation moment. In the case of an asymmetric vortex (hereinafter referred to as an asymmetric vortex) in which the maximum half circumference of the outermost outer surface of the orbiting scroll is involved in the compression chamber formation and the stroke volume is increased (hereinafter referred to as an asymmetric vortex), the fluctuation of the rotation moment increases, May reverse. The reversal of the rotation moment is the reverse of the reaction force acting on the Oldham ring claw.

  As a method of dealing with such fluctuations in the rotation moment, scroll compression that suppresses fluctuations in the key reaction force between the orbiting scroll and the Oldham ring using the inertial force of the weight of the Oldham ring that reciprocates. A machine is disclosed (for example, see Patent Document 1).

  In addition, the volume control is performed by providing a suction volume adjusting mechanism for adjusting the suction completion position in at least one of the compression chamber on the outer surface side of the orbiting scroll or the compression chamber on the inner surface side, and fluctuations in overcompression, rollover, and rotation torque There has been disclosed a scroll compressor that suppresses the influence of vibration due to (see, for example, Patent Document 2).

JP 2004-019545 A (pages 8-10 etc.) JP 2007-154761 A (pages 15-18 etc.)

  In the scroll compressor of Patent Document 1, the reciprocating direction of the Oldham ring is determined so that the fluctuation is smaller than the original rotation moment by superimposing the fluctuating rotation moment and the inertial force due to the Oldham ring weight. ing. However, the method using the inertia force of the Oldham ring is effective for the reaction force of the claw portion between the Oldham ring and the orbiting scroll, but the claw portion between the fixed member such as the fixed scroll and the Oldham ring is Oldham. The effect cannot be expected because the ring reciprocates in the direction of the nail.

  In the case of an asymmetric vortex, the fluctuation of the original rotation moment increases, and a positive / negative reversal may occur during one rotation. By using the inertial force of the Oldham ring, the repulsion of the claw reaction force between the Oldham ring and the orbiting scroll is reversed. Even if it can be avoided, the reversal of the nail reaction force between the fixed member and the Oldham ring cannot be avoided. In that case, the surface that supports the reaction force of the claw is switched, and the Oldham ring rotates with respect to the fixed member by the clearance of the claw / groove. It becomes sweet and causes fluid leakage from the radial clearance.

  Further, in the scroll compressor of Patent Document 2, the capacity is controlled by the suction volume adjusting mechanism. However, the scroll compressor is increased by asymmetric suction by the maximum half of the outermost circumference on the outer surface side of the orbiting scroll. Since the minute stroke volume is relieved and escaped, the effective stroke volume becomes the same as a symmetric spiral (hereinafter referred to as a symmetric spiral), and the advantages of employing an asymmetric spiral are lost.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a scroll compressor having an asymmetric vortex so that the original rotation moment does not reverse during one rotation.

In the scroll compressor according to the present invention, the spiral of the fixed scroll and the spiral of the orbiting scroll are formed in an asymmetric shape, and the fluid is generated in the compression chamber formed by combining the spiral of the fixed scroll and the spiral of the orbiting scroll. A scroll compressor in which the maximum value of the ratio of the rotation moment to the gas compression torque is always negative, and a frame that supports the fixed scroll and rotatably supports the orbiting scroll; A claw that is slidably inserted into the Oldham groove formed in the frame and the swing scroll is formed to prevent the swing scroll from rotating and to allow the swing scroll to swing. The tooth thickness t1 of the orbiting scroll> the tooth thickness t2 of the fixed scroll, When the Redham ring claw comes into contact with the two diagonal surfaces that regulate the rotation in the direction in which the seal point on the outer surface of the orbiting scroll opens, the posture accuracy of the orbiting scroll becomes higher than when the rotation is regulated in the opposite direction. Thus, the positional accuracy of the side surface of the Oldham groove is defined.

  According to the scroll compressor according to the present invention, since the original rotation moment is provided with an asymmetric vortex that does not reverse during one rotation, an increase in vibration and noise due to the rotation moment is suppressed, and the angle setting accuracy is improved. Low vibration, low noise and high efficiency.

It is a schematic sectional drawing which shows roughly the whole structure of the scroll compressor which concerns on embodiment of this invention. It is explanatory drawing for demonstrating the spiral shape and compression process of the fixed scroll of the scroll compressor which concerns on embodiment of this invention, and a rocking scroll. It is a PV diagram which plotted change of pressure P with respect to volume V of a compression room about a symmetrical spiral and an asymmetrical spiral. It is explanatory drawing for demonstrating calculation of the gas load which acts on the rocking scroll in a general asymmetrical spiral. It is the graph which plotted the change of the rotation moment Tr with respect to the rotation angle about a symmetrical spiral and an asymmetrical spiral. Maximum value of the ratio of rotation moment to gas compression torque when an asymmetric vortex with a built-in volume ratio ρ = 2.19 is operated at CT / ET (condensation temperature / evaporation temperature) = 52/5 [° C.] of refrigerant R410A And the minimum value are plotted against the tooth thickness difference using the parameter (t1 + t2) / p. It is the graph which plotted (t1 + t2) / p + ν which gives the rotation moment reversal limit of the spiral of a different specification with respect to ideal volume ratio ρid in each operation condition.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic cross-sectional view schematically showing the overall structure of a scroll compressor 1 according to an embodiment of the present invention. Based on FIG. 1, the structure and operation | movement of the scroll compressor 1 are demonstrated. In addition, in the following drawings including FIG. 1, the relationship of the size of each component may be different from the actual one. Further, in the following drawings including FIG. 1, the same reference numerals denote the same or equivalent parts, and this is common throughout the entire specification. Furthermore, the forms of the constituent elements shown in the entire specification are merely examples, and are not limited to these descriptions.

  The scroll compressor 1 is applied to a refrigeration cycle apparatus such as a refrigerator, a freezer, a vending machine, an air conditioner, a refrigeration apparatus, or a water heater. The scroll compressor 1 sucks a fluid such as a refrigerant circulating in the refrigeration cycle, compresses it, and discharges it in a high temperature / high pressure state.

  The scroll compressor 1 includes a fixed scroll 11, an orbiting scroll 12, an Oldham ring 13, a frame 14, a shaft 15, a first balancer 16, a second balancer 17, a rotor 18, a stator 19, a sub bearing portion 20, and a discharge valve. 25 is housed in the sealed container 21. The bottom of the sealed container 21 is a sump for storing the lubricating oil 22. Further, a suction pipe 23 for sucking fluid and a discharge pipe 24 for discharging fluid are connected to the sealed container 21. The suction pipe 23 is connected to a part of the side surface of the sealed container 21, and the discharge pipe 24 is connected to a part of the upper surface of the sealed container 21.

  The fixed scroll 11 is fixed to the frame 14 fixedly supported in the sealed container 21 by bolts or the like (not shown). The fixed scroll 11 has an end plate 11a and a spiral 11b erected on one surface of the end plate 11a. Further, a discharge port 111 for discharging a compressed fluid is formed through the substantially scroll portion of the fixed scroll 11. Furthermore, a recess in which the discharge valve 25 is installed is formed at the outlet of the discharge port 111 of the fixed scroll 11. The discharge valve 25 is installed so as to cover the discharge port 111 so as to prevent backflow of fluid.

  The rocking scroll 12 performs a rocking motion without rotating with respect to the fixed scroll 11 by the Oldham ring 13. The orbiting scroll 12 has an end plate 12a and a spiral 12b erected on one surface of the end plate 12a. A hollow cylindrical boss 121 is formed at a substantially central portion of the surface of the swing scroll 12 opposite to the surface on which the spiral 12b is formed. An eccentric portion 151 provided at the upper end of a shaft 15 described later is fitted (engaged) with the boss portion 121.

  The fixed scroll 11 and the orbiting scroll 12 are fitted in the hermetic container 21 so that the spiral 11 b and the spiral 12 b are engaged with each other. And between the spiral 11b and the spiral 12b, the compression chamber 4 whose volume changes relatively is formed.

  The Oldham ring 13 is disposed on the thrust surface (the surface opposite to the spiral forming surface) of the orbiting scroll 12 and functions to prevent the orbiting scroll 12 from rotating. That is, the Oldham ring 13 serves to prevent the swinging motion of the swing scroll 12 and to enable the swinging motion of the swing scroll 12. The upper and lower surfaces of the Oldham ring 13 are formed with claws (not shown) projecting so as to be orthogonal to each other. The claws of the Oldham ring 13 are fitted into Oldham grooves (not shown) formed in the swing scroll 12 and the frame 14.

  The rotor 18 is fixed to the shaft 15 and is rotationally driven when the energization of the stator 19 is started to rotate the shaft 15. A second balancer 17 is attached to the lower surface of the rotor 18. The second balancer 17 has a function of rotating together with the rotor 18 to obtain a mass balance (static and dynamic balance) with respect to this rotation. The second balancer 17 is attached to the rotor 18 with rivets or the like.

  The stator 19 is disposed on the outer peripheral side of the rotor 18 with a predetermined gap, and the rotor 18 is rotationally driven by disclosing energization. Further, the outer peripheral surface of the stator 19 is fixedly supported on the sealed container 21 by shrink fitting or the like.

  The shaft 15 is rotationally driven together with the rotor 18 by energization of the stator 19, and transmits this driving force to the swing scroll 12 mounted on the eccentric portion 151. In addition, an oil supply path (not shown) serving as a flow path for the lubricating oil 22 stored at the bottom of the sealed container 21 is formed inside the shaft 15.

  A first balancer 16 is attached to a portion of the shaft 15 located above the rotor 18. The first balancer 16 has a function of rotating together with the shaft 15 and achieving a mass balance (static and dynamic balance) with respect to this rotation. The first balancer 16 is attached to the shaft 15 by shrink fitting or the like.

  The outer peripheral surface is fixed to the inner peripheral surface of the sealed container 21 by shrink fitting, welding, or the like, supports the fixed scroll 11, and supports the shaft 15 rotatably through a through hole formed in the center. 14 is installed. This frame 14 also has a function of rotatably supporting the swing scroll 12. A through-hole in the frame 14 is provided with a main bearing portion (not shown) that rotatably supports the shaft 15. The frame 14 is formed with a suction port 14 a that guides the refrigerant gas existing in the upper space of the motor (the rotor 18 and the stator 19) to the compression chamber 4.

  Further, the outer peripheral surface is fixed to the inner peripheral surface of the sealed container 21 by shrink fitting, welding, or the like, and a subframe 14A that rotatably supports the shaft 15 through a through hole formed in the central portion is installed. Yes. A sub-bearing portion 20 that rotatably supports the shaft 15 is provided in the through hole of the sub frame 14A. The sub frame 14 </ b> A is installed below the sealed container 21 so as to support the lower portion of the shaft 15.

The operation of the scroll compressor 1 will be described.
When electric power is supplied to the stator 19, the rotor 18 generates torque, and the shaft 15 supported by the main bearing portion and the sub bearing portion 20 of the frame 14 rotates. The swing scroll 12 whose boss 121 is driven by the eccentric portion 151 of the shaft 15 is controlled to rotate by the Oldham ring 13 and swings. In other words, the oscillating scroll 12 is driven by the eccentric portion 151 of the shaft 15 while the boss portion 121 of the oscillating scroll 12 is driven by the eccentric portion 151 of the shaft 15 while the rotation is restricted by the Oldham ring 13 reciprocating in the Oldham groove direction of the frame 14. Swing motion. Thereby, the volume of the compression chamber 4 formed in combination with the spiral 11b of the fixed scroll 11 is changed.

  The gas-state fluid sucked into the sealed container 21 from the suction pipe 23 with the swing motion of the swing scroll 12 is taken into the compression chamber 4 between the spirals of the fixed scroll 11 and the swing scroll 12 and compressed. To go. The compressed fluid is discharged from the discharge port 111 provided in the fixed scroll 11 against the discharge valve 25 and is discharged from the discharge pipe 24 to the outside of the scroll compressor 1, that is, to the refrigerant circuit.

  The unbalance accompanying the movement of the orbiting scroll 12 and the Oldham ring 13 is balanced by the first balancer 16 attached to the shaft 15 and the second balancer 17 attached to the rotor 18. The lubricating oil 22 stored in the lower part of the sealed container 21 is supplied to each sliding part (main bearing part, auxiliary bearing part 20, thrust surface, etc.) from an oil supply path provided in the shaft 15.

  FIG. 2 is an explanatory diagram for explaining the spiral shape and compression process of the fixed scroll 11 and the swing scroll 12 of the scroll compressor 1. Based on FIG. 2, the spiral shape and compression process of the fixed scroll 11 and the swing scroll 12 of the scroll compressor 1 will be described. In FIG. 2, the thin line represents the fixed scroll 11, and the thick line represents the orbiting scroll 12 combined with the fixed scroll 11.

  (A) has shown the state of the completion | finish of inhalation in which the outermost chamber of the outward surface side of the rocking scroll 12 combined with the fixed scroll 11 was formed. (B) has shown the state when it exists in the position which the rocking scroll 12 revolved 90deg from the state of (a). (C) has shown the state when the rocking scroll 12 exists in the position which revolved 180 degrees from the state of (a). (D) has shown the state when it exists in the position which the rocking scroll 12 revolved 270deg from the state of (a). That is, the orbiting scroll 12 performs an orbiting motion, that is, a revolving motion that does not involve rotation, in the order of (a) → (b) → (c) → (d) → (a).

  Thereby, each compression chamber 4 decreases in volume. Accordingly, the sucked gas fluid is compressed and sequentially sent to the center, and is discharged from the innermost chamber (0th chamber) to the discharge port 111 (not shown in FIG. 2) provided in the fixed scroll 11. Then, it is discharged to the outside of the scroll compressor 1.

  Out of the compression chambers 4 formed by the outward surface of the orbiting scroll 12 and the inward surface of the fixed scroll 11, the second outermost chamber is at the completion of suction = compression start at the time of 0 deg, and its pressure is P2o. The second chamber becomes the first chamber on the inner side after rotation, and the pressure becomes P1o. The first chamber communicates with the first chamber on the swinging inward surface / fixed outward surface side after one revolution and is at a pressure P0.

  The outermost (second) chamber on the oscillating inward surface / fixed outward surface side is 180 deg. Of suction completion = compression has started, and at this point, the second chamber on the oscillating outward surface / fixed inward surface side is already 1 / Since the compression process is advanced by two rotations, P2o is higher than P2i. The same applies to P1o and P1i of the first chamber on the inner side of the circuit, and this situation continues until the compression chambers on the oscillating inward surface side and the oscillating outward surface side communicate with each other and become the innermost chamber of pressure P0. In the case of a normal symmetrical spiral, the suction completion on the swinging outward surface side is the same timing as the suction completion on the swinging inward surface side, and the pressures in the corresponding compression chambers 4 are always equal in principle.

  FIG. 3 is a PV diagram in which changes in pressure P are plotted against compression chamber volume V for symmetric and asymmetric vortices. The situation shown in FIG. 2 will be described in detail based on FIG. FIG. 3A shows a PV diagram in the case of a symmetrical spiral. FIG. 3B shows a PV diagram in the case of an asymmetric spiral. In FIG. 3, the horizontal axis represents the compression chamber volume, and the vertical axis represents the compression chamber pressure.

  In the case of a symmetrical spiral as shown in FIG. 3 (a), the compression chambers 4 on the oscillating outward surface / fixed inward surface side and the oscillating inward surface / fixed outward surface side simultaneously complete the suction with the same volume. The compression process also follows the same pressure rise, and the pressure Pout on the oscillating outward surface side and the pressure Pin on the oscillating inward surface side with respect to the volume V at a certain rotation angle are equal.

  On the other hand, in the case of the asymmetric spiral, as shown in FIG. 3B, the compression chamber on the swinging outward surface / fixed inward surface side has a larger stroke volume Vsto than the compression chamber on the swinging inward surface / fixed outward surface side. The suction is completed in advance, and in the compression chamber on the swinging inward surface side, the compression process proceeds from the stroke volume Vsti with a delay toward the swinging outward surface side. Therefore, in the case of the asymmetrical spiral, the pressure Pout on the rocking outward surface side with respect to a certain volume V continues to be higher than the pressure Pin on the rocking inward surface side until it communicates with the innermost chamber.

  As described above, in the asymmetrical spiral, the gas acting on the orbiting scroll is generated because the seal point formation start timing on the orbiting outward surface side is early, and the pressures of the corresponding compression chambers on the orbiting outward surface side and the orbiting inward surface side are different. The effect on the load appears as an increase in the fluctuation of the rotation moment of the orbiting scroll. For example, in FIG. 2 (c), in the case of a symmetric vortex with equal tooth thickness, P2o = P2i, P1o = P1i, and it is not necessary to perform gas load calculation. Between P2o and P2i, between P1o and P1i The differential pressure must also be taken into account for the oscillating scroll spiral for half a circle.

  Further, at 180 deg, the inward surface side compression chamber of the swing has an inward surface side stroke volume Vsti. In the case of a symmetric shape, the outward surface side stroke volume Vsto is also equal, so that the stroke volume Vst = Vsti + Vsto = as a compressor. Since 2 * Vsti (= 2 * Vsto) is an asymmetrical shape, Vst> Vsti and Vst = Vsti + Vsto> 2 * Vsti. The volume V1 of the first chamber (the sum of the outward surface side V1o and the inward surface side V1i) at the time when the innermost chamber of pressure P0 and the first chambers of pressure P1o and P1i on the outer circumference of the pressure communicate with each other is symmetrical on the outermost periphery. However, even if it is asymmetric, the built-in volume ratio (Vsto + Vsti) / V1 is higher than that of the symmetrical shape. Therefore, the stroke volume and the built-in volume ratio can be increased by asymmetry.

  FIG. 4 is an explanatory diagram for explaining calculation of a gas load acting on a swing scroll in a general asymmetric spiral. Based on FIG. 4, calculation of the gas load acting on the orbiting scroll in a general asymmetric spiral will be described. In FIG. 4, (a) explains the calculation of the gas load acting on the spiral between the oscillating inward surface side compression chamber and the oscillating outward surface side compression chamber, and (b) shows the calculation of the oscillating outward surface side compression chamber to the oscillating surface. The explanation of the calculation of the gas load acting on the spiral between the dynamic inward surface side compression chambers is shown respectively.

  In FIG. 4A, the hatched portion of the spiral 12b of the orbiting scroll 12 indicated by the solid line is the differential pressure between the pressure Pni in the inward surface side nth chamber and the pressure P (n + 1) o in the outward surface side n + 1 chamber. (However, the innermost chamber is P0, and the outermost periphery is the suction pressure Ps). Since the distance between seal points is Lni (n + 1) o, the force Fio corresponding to the sum of h (tooth height) × Lni (n + 1) o × (Pni−P (n + 1) o) is resisted. The orbiting scroll 12 must be driven. Further, regarding the differential pressure (Pno−Pni) acting on the shaded portion of the seal point distance Lnoi in FIG. 4B, h × Lno × (Pno−Pni), which is not required to be calculated by assuming that Pno = Pni in the symmetrical spiral. ) Is added, and Rr (oscillation radius) × (Fio + Foi) is the torque Tθ required for gas compression.

  At this time, since the action point of Fio, Foi and the center of the orbiting scroll 12 do not coincide with each other, Fio and Foi act to rotate (rotate) the orbiting scroll 12 around the center. This is referred to as the rotation moment Tr. The size refers to the distance between the center of the orbiting scroll and the action point in FIG. 4, and the inward side → outward side is Fio × Rr / 2, and p is the spiral pitch. Since the direction from the outward surface side to the inward surface side is reversed, −Foi × (p−Rr) / 2.

  As described above, in the case of a symmetric spiral having an equal tooth thickness, the differential pressure from the outward surface side to the inward surface side can be regarded as 0. Therefore, the sum of the inward surface side to the outward surface side may be added, and the gas compression torque is Tθ. = Rr × Fio, and the rotation moment is Tr = Rr / 2 × Fio = Tθ / 2. The direction of rotation was constant in the direction in which the rocking outward surface side seal point was closed and the direction in which the rocking inward surface side seal point was opened. On the other hand, in the case of an asymmetric spiral, the rotation moment is Tr = Fio × Rr / 2−Foi × (p−Rr) / 2 = (Fio + Foi) × Rr / 2−Foi × p. It will be possible.

  The Oldham ring 13 for regulating the rotation of the orbiting scroll 12 is originally intended to regulate the posture with respect to the rotation moment in one direction. The two diagonal surfaces that regulate the rotation in the direction in which the seal point on the swinging outward surface side closes are used, and the remaining two diagonal surfaces are not used. For this reason, with respect to the Oldham groove formed in the frame 14 or the orbiting scroll 12 and into which the claws of the Oldham ring 13 are inserted, the positional accuracy of the two faces corresponding to the two diagonal faces of the claws used for posture adjustment is specified. In general, it is possible to ensure the posture adjustment accuracy of the orbiting scroll.

  Therefore, there is a relatively large clearance between the groove width dimension and the claw width dimension on the two diagonal surfaces that are not used for posture adjustment of the Oldham claw. Therefore, when the rotation moment is reversed, the claw portion of the Oldham ring slides. Such a usage should be avoided because the surface is inverted, causing vibration and noise due to the rotation of the claw / groove clearance, and increased leakage from the spiral side clearance.

  Whether or not the rotation moment is reversed depends on the magnitude of Foi from the above calculation formula. Foi originally accelerated the suction of the compression chamber on the outer surface of the orbiting scroll, and the compression chamber on the outer surface side. This is the force exerted by the differential pressure generated by the compression process preceding the compression chamber on the inward surface side. For this reason, in general, the suction completion of the orbiting scroll outward surface side to the inward surface side = the larger the difference in compression start angle (extended expansion angle φex ≦ 180 deg), the greater the stroke volume between the orbiting scroll outer surface side and the inward surface side. It can be said that the greater the difference (Vsto-Vsti), the greater the fluctuation of the rotation moment.

  FIG. 5 is a graph in which the change of the rotation moment Tr is plotted with respect to the rotation angle for the symmetric vortex and the asymmetric vortex. Based on FIG. 5, the change of the rotation moment Tr calculated from the PV diagram shown in FIG. 3 will be described. FIG. 5A shows a graph in which the change of the rotation moment Tr in the case of a symmetric spiral is plotted against the rotation angle. FIG. 5B shows a graph in which the change of the rotation moment Tr in the case of the asymmetric spiral is plotted with respect to the rotation angle. In FIG. 5, the horizontal axis indicates the rotation angle ψ, and the vertical axis indicates the rotation moment Tr with respect to the rotation angle.

  Although the horizontal axis in FIG. 5 is the rotation angle, the innermost chamber is not used in order to compare and compare spirals having different suction completion timings instead of setting 0 deg at the time of completion of suction on the swinging outward surface side as shown in FIG. And the first chamber (the swinging outward surface side, the swinging inward surface side) on the outer side thereof communicate with each other at 180 degrees.

  In FIG. 5, the symmetrical spiral of (a) is always Tr> 0, and the Oldham ring claw reaction force for posture correction is only in one direction, whereas the symmetrical spiral of (b) is a symmetrical spiral. Compared to the above, the average value of Tr decreases and the fluctuation increases. Therefore, it can be seen that there is both a range of Tr> 0 and a range of Tr <0 during one rotation. In this way, if the sign of the rotation moment is reversed during one rotation, the Oldham ring cannot be posture-corrected by only two diagonal surfaces on one side of the claw.

  The fluctuation expansion factor of the rotation moment Tr is the gas force Foi acting from the outward surface side to the inward surface side of the orbiting scroll, which was negligible because there is no differential pressure due to the symmetrical spiral, and the position of the action point Foi is This depends on the difference between the stroke volume Vsto on the outer surface side of the orbiting scroll and the stroke volume Vsti on the inner surface side.

  In a spiral having “different tooth thickness” in which the tooth thickness of the orbiting scroll is different from that of the fixed scroll, Vsto and Vsti are different even in a symmetric spiral. If t1 is the tooth thickness of the orbiting scroll, t2 is the tooth thickness of the fixed scroll, and p is the common spiral pitch between the oscillation / fixation, then Vsto / Vsti increases when t1> t2, and the volume difference increases. The action point of Fio is Rr / 2 = (p−t1−t2) / 4, and the action point of Foi is − (p−Rr) / 2 = (p−t1−t2) / 4−p / 2 = −. The point is (p + t1 + t2) / 4, that is, ± p / 4− (t1 + t2) / 4 with respect to the center of the orbiting scroll.

  For such an asymmetric vortex, in order to sort out the influence of the vortex spec on the fluctuation of the rotation moment without the restriction of uniform tooth thickness / different tooth thickness, (t1 + t2) / p and Vsto / Vsti are selected as dimensionless parameters and The moment Tr is expressed in a dimensionless manner by the gas compression torque Tθ (see FIG. 6).

FIG. 6 shows the rotational moment relative to the gas compression torque when an asymmetrical vortex with a built-in volume ratio ρ = 2.19 is operated at CT / ET (condensation temperature / evaporation temperature) = 52/5 [° C.] of the refrigerant R410A. It is the graph which plotted the maximum value and minimum value of ratio with respect to tooth thickness difference using parameter (t1 + t2) / p. The rotation moment and gas compression torque will be described based on FIG. FIG. 6A is a graph in which the maximum value / minimum value is plotted with respect to the swing / fixed tooth thickness difference, and FIG. 6B is an enlarged view of the maximum value side of FIG. The stroke volume ratio Vsto / Vsti between the swinging outward surface side and the inward surface side is made dimensionless with the _{equal tooth thickness} (Vsto / Vsti) in the case of a _{constant tooth thickness} , and the horizontal axis is read again.

  Since the maximum value side is in the vicinity of 0 as shown in FIG. 6A, it is presumed that Tr <0 in most of one rotation as shown in FIG. 5B. FIG. 6A is a summary of the maximum value and the minimum value of FIG. 5B as the ratio Tr / Tθ with respect to the gas compression torque Tθ. Therefore, the maximum value and the minimum value do not cross zero, and both are <0 or If both are> 0, the rotation moment does not reverse during one rotation.

That is, the point where MAX (Tr / Tθ) crosses 0 for each value of parameter (t1 + t2) / p in FIG. 6B is the reversal limit of the rotation moment, and ν = (Vsto / Vsti) than that. ) / (Vsto / Vsti) If the _{tooth thickness} is large, Tr is always on the negative side during one rotation, which is the reverse of the normal case for the same tooth thickness symmetric spiral, but both sides of the Oldham ring claw are It will not be used for regulation. Such a rotation moment reversal limit point (t1 + t2) / p + ν is substantially constant. This indicates that the degree of influence of the dimensionless parameter (t1 + t2) / p and ν on the inversion limit is almost equal.

  FIG. 7 is a graph in which (t1 + t2) / p + ν, which gives the rotation moment reversal limit of the spirals of different specifications, is plotted against the ideal volume ratio ρid in each operating condition. That is, FIG. 7 shows that (t1 + t2) / p + ν of the inversion limit when the high and low pressures are changed with a spiral having a different built-in volume ratio ρ, and ρid = (specific volume in the suction state) at each high and low pressure. It is plotted against / (specific volume in the discharge state). Based on FIG. 7, the rotation moment and the gas compression torque will be further described.

FIG. 7 shows the “rotational moment reversal limit line”, and the function of the ratio ρid of the suction / discharge specific volume under a certain operating condition of R410A (equation (1) below) is the (t1 + t2) / If p + ν or less, it indicates that the rotation moment does not reverse.
Formula (1):
L (ρid) = − 0.009 · ρid ⁴ + 0.1427 · ρid ³ −0.8589 · ρid ² + 2.3868 · ρid−0.8934

  Therefore, in the spiral design, (t1 + t2) / p + ν is larger than L (ρid) for the condition in which the ideal volume ratio ρid is highest among the operating conditions that particularly require low vibration, low noise, and high efficiency. By selecting the vortex spec, it is possible to obtain a vortex that does not cause rotation moment reversal in normal operation. In addition, by defining the position accuracy of the two diagonal surfaces that regulate the rotation of the rocker scroll outward face seal point in the frame and the Oldham groove of the rocking scroll, the low-vibration, low-noise and angle-regulating accuracy is ensured. As a result, a highly efficient scroll compressor can be obtained.

Therefore, in the scroll compressor 1 according to the present embodiment, the asymmetric scrolls having different tooth thicknesses of the orbiting scroll 12 and the fixed scroll 11 are used, the tooth thickness of the orbiting scroll is t1, the tooth thickness of the fixed scroll is t2, and the spiral pitch. (T1 + t2) / p where p is the same for rocking / fixing, and the stroke volume Vsto on the outer surface side of the rocking scroll and the stroke volume Vsti on the inner surface side, which are different due to asymmetry, the ratio Vsto / VSTi ratio (Vsto / VSTi) for the case equal tooth thickness (≠ 1) / (Vsto / Vsti) _TohaAtsu = and ν as a parameter, (specific volume of the inhalation state) Roid = the predetermined operating condition / The shape satisfies a function (equation (1)) of (specific volume in a discharge state).

  As a result, the scroll compressor 1 according to the present embodiment is configured so that the asymmetric vortex is formed of a “different tooth thickness” vortex satisfying the above-described formula (1), so that the rotation moment acting on the orbiting scroll 12 is rotated once. Inversion is prevented from occurring. That is, the scroll compressor 1 employs an asymmetric vortex that does not reverse the original rotation moment during one rotation, avoids the rotation of the Oldham ring 13 without invalidating the increase in stroke volume due to the asymmetric vortex, and vibrates.・ Along with the reduction of noise, the angle adjustment accuracy equivalent to that of a symmetrical spiral is ensured to improve performance by reducing fluid leakage. This makes it possible to avoid the reversal of the rotation moment without losing the merit of the asymmetrical spiral, which is an increase in the stroke volume in a limited space, and achieves high efficiency by ensuring angle adjustment accuracy with low vibration and low noise. It will be a thing.

  1 scroll compressor, 4 compression chamber, 11 fixed scroll, 11a end plate, 11b spiral, 12 orbiting scroll, 12a end plate, 12b spiral, 13 Oldham ring, 14 frame, 14A subframe, 14a inlet, 15 shaft, 16 first 1 balancer, 17 second balancer, 18 rotor, 19 stator, 20 auxiliary bearing part, 21 sealed container, 22 lubricating oil, 23 suction pipe, 24 discharge pipe, 25 discharge valve, 111 discharge port, 121 boss part, 151 eccentric part .

Claims (2)

Swirl Swirl and the orbiting scroll of the fixed scroll is formed asymmetrical, which compresses the fluid in compression chamber formed by combining the spiral of the orbiting scroll and the spiral of the fixed scroll, the rotating moment A scroll compressor in which the maximum value of the ratio to the gas compression torque is always negative ,
A frame that supports the fixed scroll and rotatably supports the orbiting scroll;
A claw that is slidably inserted into the Oldham groove formed in the frame and the orbiting scroll is formed to prevent the orbiting scroll from rotating and the orbiting scroll can be orbited. With an Oldham ring,
The tooth thickness t1 of the orbiting scroll> the tooth thickness t2 of the fixed scroll,
When the Oldham ring claw comes into contact with two diagonal surfaces that regulate the rotation in the direction in which the seal point on the outer surface of the orbiting scroll opens, the posture accuracy of the orbiting scroll is higher than that when the rotation is reversed in the opposite direction. The scroll compressor is characterized in that the positional accuracy of the side surface of the Oldham groove is defined. In what uses R410A as a refrigerant,
For the following formula (1), which is a function of the ratio ρid of the suction / discharge specific volume under a predetermined operating condition, where the scroll pitch of each scroll is p.
(T1 + t2) / p,
The ratio (Vsto / Vsti) / (Vsto / Vsti) _TohaAtsu = [nu for the case the stroke volume Vsto of the swing scroll outwardly facing surface side with an equal tooth thickness ratio Vsto / VSTi stroke volume VSTi the inwardly facing surface side,
The scroll compressor according to claim 1, wherein the scroll compressor has a shape in which (t1 + t2) / p + ν is equal to or greater than L (ρid).

(Formula 1)
L (ρid) = − 0.009 · ρid ⁴ + 0.1427 · ρid ³ −0.8589 · ρid ² + 2.3868 · ρid−0.8934