JP2007092546A - Fluid machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a highly efficient and silent fluid machine which is reduced in wearing in a sealing member and in an opposite surface, has long-term reliability and high airtightness, and is reduced in the sliding loss of friction. <P>SOLUTION: The fluid machine equipped with a helical compression mechanism is provided with an annular seal member which is installed in an annular groove formed on the end surface at the end side of a roller and one of a bearing surface of a bearing member to seal the end surface of the roller and the bearing surface of the bearing member. The seal member comprises a seal material composed of two lips to form a seal surface having a cross sectional U-shape and facing each other, and a heel to connect the two lips, and a spring installed inside the seal material. Out of the two lips, a projection is formed on the sliding surface of the lip at the opposite groove bottom side. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a fluid machine, and more particularly to a fluid machine having an improved seal mechanism for a helical working chamber.

  A helical compressor having a helical blade that is slidably fitted in a helical blade groove formed on an outer peripheral surface of a roller arranged eccentrically in a cylinder and that forms a plurality of working chambers. The compressor requires a seal member (hereinafter referred to as a seal ring) between the discharge side of the compression chamber and the driving unit of the roller (a portion in the atmosphere such as a crankshaft, a ball bearing, and an Oldham ring).

  Conventionally, this portion is sealed with a roller end face and a secondary bearing using a seal member (varistor seal) made of PTFE resin (ethylene tetrafluoride resin) with a spring attached. This seal gap is determined by the component accuracy and assembly accuracy of the roller, cylinder, and auxiliary bearing, and the fluctuation width (size, parallelism) of the seal gap increases. In addition, the seal ring is crushed during mounting. However, if the rigidity is high and the pressing force is large, there is a problem that power consumption increases due to increased wear and frictional resistance.

  Therefore, an oblique winding coil spring having a small pressing force and a wide movable range is used for the spring.

  The seal ring is mounted in a free state in a groove provided in either the roller or the bearing. In a seal member that can be fixed like a flange type, the variation width of the seal gap cannot be allowed, and fixing one of the seal members may cause a decrease in sealing performance.

  In other words, unlike a seal around a rotating shaft in which this type of seal material is generally used, the number of parts constituting the seal portion is large, so that the fluctuation range of the seal gap increases, and the seal ring having the above configuration is used. .

  The conventional configuration has the following problems.

  When the contact state of the seal member is unstable and the contact surface on the initial sliding side is wide, (1) the initial familiarity of the sliding surface is hindered, and (2) the wear powder is poorly discharged and the wear powder is bitten. (3) The contact surface further expands due to wear, the frictional resistance increases, the compressor performance decreases (large friction loss), (4) The groove rotates due to increased frictional resistance, and further wear It has become a vicious cycle of advancing, and there has been a problem in the long-term reliability of the compressor performance.

  In addition, in a conventional helical compressor, the rollers may move in an unstable manner during a transition such as when starting or when operating conditions are changed, and there is a possibility that problems such as noise, vibration, and wear may occur due to contact with the cylinder.

In addition, about the improvement of the sliding part of a fluid machine, the proposal like patent document 1 and patent document 2 is made | formed.
Japanese Patent Laid-Open No. 2003-3978 JP 2003-97464 A

  The present invention has been made in consideration of the above-mentioned circumstances, the wear of the seal member and the mating surface is small, long-term reliability, high confidentiality, low sliding loss due to friction, high performance, An object is to provide a quiet fluid machine.

  In order to achieve the above-described object, a fluid machine according to the present invention includes a cylinder, a roller that is eccentrically disposed in the cylinder and provided with a spiral groove from one end side toward the other end side, and the spiral groove. A spiral blade that is fitted in and out freely to form a plurality of working chambers between the cylinder and the roller, and a working fluid that is sucked into the working chamber on one end side by rotating the roller eccentrically in the cylinder The other end side of the roller, a bearing member that supports the crankshaft and supports the thrust load of the roller, and an end surface on the other end side of the roller; An annular groove provided on one of the bearing surfaces of the bearing member, and an annular seal member that is mounted in the annular groove and seals between the end surface of the roller and the bearing surface of the bearing member In the fluid machine provided, the seal member has a sealing material including two lip portions that have a U-shaped cross-section and are opposed to each other to form a seal surface, and a heel portion that connects the lip portions, It comprises a spring provided on the inner side of the sealing material, and a protrusion is provided on the sliding surface of the lip portion on the opposite groove bottom side of the two lip portions.

  According to the fluid machine of the present invention, there is provided a high-performance and quiet fluid machine with low wear on the seal member and the mating surface, long-term reliability, high confidentiality, low sliding loss due to friction, and high performance. can do.

  Hereinafter, a first embodiment of a fluid machine according to the present invention will be described by taking a horizontal helical compressor as an example with reference to the accompanying drawings.

  FIG. 1 is a longitudinal sectional view of a horizontal helical compressor as a first embodiment of a fluid machine according to the present invention.

  As shown in FIG. 1, the horizontal helical compressor 1 of the first embodiment is a casingless, helical compression mechanism portion 2 in which a large number of working chambers are formed, and an electric motor that drives the helical compression mechanism portion 2. The crankshaft 4 provided between the motor unit 3 and the helical compression mechanism unit 2 and transmitting the power of the motor unit 3 to the helical compression mechanism unit 2 is linearly arranged on the base 5.

  Further, the main bearing 6 that supports the crankshaft 4 is supported between one side of the helical compression mechanism 2 and the motor unit 3, and the crankshaft 4 is supported on the other side of the helical compression mechanism 2 and the thrust load of the roller 22 is supported. And an Oldham ring 8 constituting an anti-rotation mechanism for preventing the roller 22 from rotating, between the auxiliary bearing 7 and the roller 22 of the helical compression mechanism 2. A cooling fan 9 that cools the helical compressor 1 is provided at one end of the shaft 4.

  The electric motor unit 3 includes a motor stator 31 fixed to the main bearing 6 and a motor rotor 32 that rotates in the motor stator 31 and rotates the crankshaft 4.

  On the other hand, the helical compression mechanism section 2 has an annular roller 22 as a movable member that is eccentrically disposed in a cylinder 21 so as to be able to turn (revolve), and the volume between the roller 22 and the cylinder 21 gradually decreases in the axial direction. And blades 24 of unequal pitch that define a compression chamber 23 as a working chamber.

  On the outer peripheral surface of the roller 22, a spiral groove 22a having a predetermined size is formed so that the pitch gradually decreases from the left end of the suction port 21a side in FIG. 1 toward the right end of the discharge port 21b. A spiral blade 24 having elasticity is fitted in the blade groove 22a so as to appear and slide.

  Further, between the rotating roller 22 and the main bearing 6, there is provided a suction side seal member 25 which is inserted into a mounting groove 6a provided in the main bearing 6 to form an annular shape and has a cross-sectional shape shown in FIG. The suction-side seal member 25 has a sealing material 25c composed of two lip portions 25a that have a U-shaped cross-section and are opposed to each other to form a seal surface, and a heel portion 25b that connects the lip portions 25a to each other. The elastic member 25d is provided inside the sealing material 25c.

Further, between the roller 22 and the sub-bearing 7, a discharge side seal member 26 having a ring shape shown in FIG. 3 and a cross-sectional shape shown in FIG. 4 is provided by being inserted into a mounting groove 22b provided in the roller 22. Discharge side sealing member 26 is made of, for example, fluorocarbon resin, two lip portions _26a 1, 26a ₂ and the lip portion _26a which constitutes a seal surface cross-sectional shape to face each other without the U-shape 1, 26a ₂ to each other And a slanted winding spring 26d provided on the inner side of the sealing material 26c, of the two lip portions 26a ₁ and 26a ₂ , the bottom of the anti-groove providing an arcuate protrusion 26e on the sliding surface of the lip portion 26a ₁ of the side.

  As shown in FIG. 5, the width D1 of the arcuate protrusion 26e is preferably less than or equal to ½ of the total width D2 that can be a sliding surface. Thereby, in the initial familiarity and long-term use, even if the arc-shaped protrusion is worn, the width of the sealing surface is not increased, and the effect of the protrusion can be obtained for a long time. Further, as shown in FIGS. 5 and 6, it is preferable that the position of the arc-shaped protrusion 26e (projection center L) is disposed on the opening side with respect to the center of the full width D2 that can be the sliding surface. Thereby, the pressing force of the seal member is reduced, the surface pressure and the frictional resistance of the seal portion can be reduced, and high performance and reliability can be obtained.

Furthermore, as shown in FIG. 4 above, an inclined surface may be provided on the sliding surface of the lip portion 26a ₂ on the groove bottom side, but as shown in FIG. 7 or FIG. 8, the lip portion 26a ₃ on the groove bottom side. The heel portion 26b may be flush with the same plane. As a result, the surface to be inserted into the groove is smoothed and disposed so as to be in contact with the groove bottom on a wide surface, thereby increasing the frictional resistance with the groove bottom and suppressing the rotation of the seal member, and a stable seal. Performance can be maintained over a long period of time. Since it is not on the sliding side, there is no effect on the compressor performance due to frictional resistance.

In the present embodiment, the protrusion is described as an example of an arc shape, but the same effect can be obtained with the triangular protrusion 26e ₁ shown in FIG. 9 or the trapezoid protrusion 26e ₂ shown in FIG. as shown, it has an arc-shaped protrusions 26e to the lip portion 26a _1, and on the same plane over the lip portion 26a ₃ to the heel portion 26b, even in a configuration of mounting the leaf spring 26f, the same effect can be obtained.

  According to the horizontal helical compressor of the first embodiment, since a seal is provided with a small contact surface by providing a protrusion on the lip portion on the bottom side of the groove, the contact surface pressure is large at the initial stage of use, and the sliding surface is at the initial stage. Familiarity is fast (fluorine resin transfer film generation) and high confidentiality is obtained. In addition, sliding by swivel movement is a fine movement that continuously draws a small radius, so it is difficult to discharge wear powder, it is easy to bite, and wear (rough wear) due to wear powder occurs. A gap is always formed from the contact portion toward the closing portion, wear powder can be discharged well, the wear powder can be prevented from being caught, and wear of the seal member and the mating surface can be reduced. Furthermore, since the contact surface is small, sliding loss due to friction is small, and compressor performance is improved.

  Next, a fluid machine according to a second embodiment of the present invention will be described.

  In the second embodiment, another member having excellent sliding characteristics is added to the sliding surface including the contact surface with which the discharge side and suction side sealing members of the first embodiment are in contact.

  For example, as shown in FIGS. 1 and 12, a suction-side seal member 25 is provided between the roller 22 and the main bearing 6. A separate member 27 having excellent sliding characteristics is attached to one side surface of the roller 22 in which the suction side seal member 25 is opposed and relatively slid.

  Further, as shown in FIG. 13, a discharge-side seal member 26 is provided between the roller 22 and the auxiliary bearing 7. The discharge side seal member 26 is opposed to each other, and a separate member 27 having excellent sliding characteristics is attached to one side of the sub bearing 7.

  Further, as shown in FIG. 14, another member 27 is attached to the key portion 8 a of the Oldham ring 8 guided by the Oldham groove 7 a of the auxiliary bearing 7.

  In general, when the sliding characteristics are improved by the surface treatment of a sliding counterpart component such as a roller, the material used is limited in material, but according to the second embodiment, the optimal material is not limited by the material. A sliding member can be selected. In addition, by exchanging another member, it is not necessary to replace the entire sliding counterpart part, and the maintainability is improved. Furthermore, to improve the manufacturability of sliding mating parts, if this part is cast, even if there is a nest on the sliding surface, the effect of wear on the nest can be eliminated by interposing another part product. A highly reliable compressor is realized.

  In this way, by providing another member with excellent sliding characteristics in the sliding part, friction can be reduced, and a high-performance compressor can be realized by lowering the input. It is economical because it is economical.

  As this separate member, it is preferable to use a member having a surface roughness smaller than that of a member to be a sliding counterpart such as a roller. This realizes a high-performance compressor with high reliability, reduced friction, and low input. Also, by providing parts with high flatness, leakage on the sealing surface is reduced. Even with this, the backlash during sliding is reduced, and a higher performance compressor is realized.

  The material of the separate member is preferably a sheet made of PET (polyethylene terephthalate) or the like having a small surface roughness or good flatness. As a result, it is possible to easily obtain a product having good surface accuracy, and it is easy to perform processing suitable for the part shape.

  Further, the separate member is preferably a thin plate. If it is a thin plate, even if the flatness of the separate member itself is slightly worse, the shape follows that of the other parts when assembled, so it is easy to obtain good flatness in the assembled state.

  The thin plate is preferably covered with a solid lubricating film. As a result, it is possible to select a material having further excellent sliding characteristics, and a high-reliability, low-friction, high-performance compressor with low input is realized.

  A fluid machine according to a third embodiment of the present invention will be described.

  In the third embodiment, a tapered portion is formed on the outer periphery of the roller of the first embodiment, and a solid lubricating film is formed on the tapered portion.

For example, as shown in FIG. 15, the roller 22 of the lateral helical compressor of the third embodiment is formed a tapered portion 22c ₁ on the outer peripheral surface 22c, forming a solid lubricant film 28 on the surface of the tapered portion 22c ₁ To do.

  The roller / cylinder clearance is preferably small to reduce leakage and improve volumetric efficiency, but the roller may move in an unstable manner and come into contact with the cylinder during transitions such as during startup or when changing operating conditions. There is sex. Therefore, a part of the anti-Oldham side of the outer periphery of the roller is tapered to prevent contact. If taper is used, the clearance between the roller and the cylinder increases, so that leakage increases. Therefore, by applying a solid lubricant film to the tapered portion, the clearance is reduced to prevent leakage, and even when the roller movement is unstable, the solid lubricant film and the cylinder are in direct contact, and the roller is not in direct contact. Therefore, a quiet horizontal helical compressor that can solve problems such as sound, vibration, and wear is realized.

  It is preferable to change the thickness of the solid lubricant film according to the distance from the taper starting point. Applying a thick solid lubricant film in areas where the roller outer diameter is small, away from the taper starting point, and thinly in areas where the roller outer diameter in the vicinity of the taper starting point is not so small, it is almost the same as the area where no taper is provided. The diameter can reduce the clearance between the roller and the cylinder to reduce the roller from directly contacting the cylinder.

  In addition, as shown in FIG. 16, it is preferable to apply and form a solid lubricant film 29 on a portion corresponding to the suction side first chamber on the outer periphery of the roller 22. Thereby, the clearance between the roller and the cylinder in the suction side first chamber with small thermal expansion is reduced, leakage is reduced, and volumetric efficiency is improved.

  In the fluid machines of the above embodiments, the horizontal helical compressor has been described as an example. However, the present invention can also be applied to other fluid machines.

  Using the horizontal helical compressor of the present invention shown in FIG. 1, the presence / absence of protrusions and the shape of the protrusions are changed as shown in Table 1 and below, and the power consumption, wear amount, and compressive stress shown in Table 2 are examined. It was. Endurance time is 100 hours and 1000 hours, and the pressing force changes when mounting due to the difference in the shape of the seal ring, resulting in increased contact pressure and frictional resistance of the sliding part. The relative compression stress was compared.

[Example 1]
As shown in FIGS. 5 and 6, an oblique coil spring is inserted into a PTFE resin seal outer shell, and an arc-shaped protrusion is provided on the seal portion (referred to as a lip portion) on the side opposite to the groove on the opening side. Further, a step is provided in the closed portion (referred to as a heel portion). There is a minimum gap between the lip height (H) that allows sufficient contact with the maximum gap between the ring-shaped mounting groove on the roller side and the sliding surface on the countershaft side (referred to as the seal gap). Also with respect to (K2), a gap (W) is provided between the lip portion of the arcuate protrusion and the stepped portion of the heel portion between the secondary shaft side sliding surface. That is, a gap (W) can be secured in the range of the seal gap to be used, and the tip of the protrusion comes into contact with the sliding surface.

  The width (D1) of the arc-shaped protrusion is the same as the seal width (D2) up to the heel step (D1 = D2). The contact portion is disposed at a position (L) that is ½ of the seal width (D2). Hereinafter, the height between the lips (H) and the minimum seal gap (K) are matched in order to achieve the same conditions.

[Example 2]
Although it is the same structure as Example 1, the width | variety of a processus | protrusion (D1) is made into circular arc shape of length 1/2, 1/3, and 1/7 with respect to the seal width (D2) to a heel level | step difference. The contact portion is arranged at a position (L) that is 1/2 with respect to the same seal width (D2) as in the first embodiment.

[Example 3]
As in the second embodiment, the protrusion width (D1) is an arc shape that is 1/3 of the seal width (D2) up to the heel step, but the contact portion is 1 for the seal width (D2). / 3 and 1/6 (L).

[Example 4]
7 has a structure as shown in FIG. 7, and the anti-sliding surface (surface on the groove insertion side) is smoother than that of Example 1 in FIG. The configuration of the lip portion is the same as that of the first embodiment, and the width (D1) of the arc-shaped protrusion is the same as the seal width (D2) (D1 = D2). The contact portion is disposed at a position (L) that is ½ of the seal width (D2).

[Comparative Example 1]
The conventional seal ring shown in FIGS. 17 to 19 has no protrusion, but the height (H) between the lips and the contact point are the same as those in Example 1 (protrusion position). Further, the gap (W2) is small with respect to the minimum seal gap (K2), and surface contact is easy.

The survey results are shown in Table 2.

As can be seen from Table 2,
(1) Since the compression stress (relative ratio) is the same for the mounting spring, the bending rigidity of the lip, the height between the lips (H), and the seal gap (K), the position of the action point (contact point) when compressed Related to. In other words, the protrusion provided at the tip of the opening can be sandwiched with a small force due to the difference in moment. Therefore, the contact stress (surface pressure) of the protrusion, which is the reaction force, is also reduced.

  Hereinafter, a specific comparison will be made.

(2) Example 1 (Comparison with Comparative Example 1)
When power consumption is 100H and the power consumption of Comparative Example 1 is 1, the reduction is 0.02 (2%), and the increase after 1000H is small, which is due to the difference in frictional resistance due to the dimensional difference of the contact portion. Since the compressive stress is the same, the effect of improving the sliding characteristics by the protrusion can be confirmed. On the other hand, it can be seen that in Comparative Example 1, the wear amount increased after 1000H, and the reliability was poor. In addition, sliding flaws were found on the inner peripheral surface of the closed portion of the seal ring, and there were traces of rotation in the roller premises.

  In Example 1, some sliding scratches were seen on the inner peripheral surface of the closed portion of the seal ring, and there was a trace of slight rotation in the roller premises.

(3) Example 2 (Comparison with Comparative Example 1 and Example 1)
The power consumption of Example 2 is lower than that of Comparative Example 1, and the increase after 1000H is smaller. Also, the width of the protrusion is smaller than that of Example 1, so that the power consumption is higher than that of Example 1. The amount of wear has been improved. However, in Example 3 (3), the width 1/7 of the protrusion was too small and was worn at the initial familiarization stage, and the amount of wear increased after 1000 H compared to Example 1. Therefore, it can be seen that the width of the protrusion in the range of less than 1/2 and exceeding 1/7 of the sealable surface is suitable.

(4) Example 3 (Comparison with Comparative Example 1 and Example 2)
In Example 3, the position of the protrusion is arranged at the end of the opening, so that the power consumption is reduced compared to Comparative Example 1, the amount of wear after 1000 H is small, and the compressive stress is also small compared to Example 2. Therefore, the effect of the protrusion can be maximized, and the power consumption and the amount of wear are minimized. Therefore, it can be seen that the position of the protrusion is more than 1/2 of the surface that can be sealed and the arrangement on the opening side is suitable.

(5) Example 4 (Comparison with Comparative Example 1 and Example 1)
In Example 4, the anti-sliding surface was smooth, and compared with Comparative Example 1, the power consumption was reduced, the amount of wear after 1000H was small, and the amount of wear was also improved. Further, compared with Example 1, the amount of wear at 1000H is suppressed, and therefore rotation is suppressed by the effect of increasing the contact area by smoothing the surface on the groove insertion side, and high reliability is obtained over a long period of time. It is done.

The longitudinal cross-sectional view of 1st Embodiment of the fluid machine which concerns on this invention. The longitudinal cross-sectional view of the suction side sealing member used for 1st Embodiment of the fluid machine which concerns on this invention. The top view of the discharge side sealing member used for 1st Embodiment of the fluid machine which concerns on this invention. The longitudinal cross-sectional view of the discharge side sealing member used for 1st Embodiment of the fluid machine which concerns on this invention. The longitudinal cross-sectional view which expands and shows the arc-shaped protrusion of the discharge side sealing member of FIG. The longitudinal cross-sectional view which shows the circular arc-shaped protrusion of the discharge side sealing member which concerns on this invention. The longitudinal cross-sectional view which shows other embodiment of the circular-arc-shaped protrusion of the discharge side sealing member which concerns on this invention. The longitudinal cross-sectional view which shows other embodiment of the circular-arc-shaped protrusion of the discharge side sealing member which concerns on this invention. The longitudinal cross-sectional view which shows other embodiment of the circular-arc-shaped protrusion of the discharge side sealing member which concerns on this invention. The longitudinal cross-sectional view which shows other embodiment of the circular-arc-shaped protrusion of the discharge side sealing member which concerns on this invention. The longitudinal cross-sectional view which shows other embodiment of the circular-arc-shaped protrusion of the discharge side sealing member which concerns on this invention. The longitudinal cross-sectional view which shows the attachment state of another member used for 2nd Embodiment of the fluid machine which concerns on this invention. The longitudinal cross-sectional view which shows the attachment state of another member used for 2nd Embodiment of the fluid machine which concerns on this invention. The longitudinal cross-sectional view which shows the attachment state of another member used for 2nd Embodiment of the fluid machine which concerns on this invention. The longitudinal cross-sectional view of the roller used for 3rd Embodiment of the fluid machine which concerns on this invention. The side view of the roller used for 3rd Embodiment of the fluid machine which concerns on this invention. The longitudinal cross-sectional view of the discharge side sealing member used for the conventional fluid machine. The longitudinal cross-sectional view of the discharge side sealing member used for the conventional fluid machine. The longitudinal cross-sectional view of the discharge side sealing member used for the conventional fluid machine.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Horizontal type helical compressor, 2 ... Helical compression mechanism part, 3 ... Electric motor part, 4 ... Crankshaft, 6 ... Main bearing, 7 ... Secondary bearing, 8 ... Oldham ring, 6a ... Mounting groove, 21 ... Cylinder, 22 ... roller, 22a ... cam groove, 22b ... mounting groove 23 ... compression chamber, 24 ... blade, 25 ... suction side seal member, 26 ... discharge side sealing member, 26a 1 _... lip portion, 26a 2 _... lip portion, 26b ... Heel part, 26c ... sealing material, 26d ... slant winding spring, 26e ... arc-shaped protrusion.

Claims (4)

A cylinder,
A roller arranged eccentrically in this cylinder and provided with a spiral groove from one end to the other end;
A spiral blade that is fitted in the spiral groove so as to be freely retractable and forms a plurality of working chambers between the cylinder and the roller;
A crankshaft that transfers the working fluid sucked into the working chamber on one end side to the working chamber on the other end side by rotating the roller eccentrically in the cylinder;
A bearing member provided on an end surface of the cylinder for supporting the crankshaft and supporting a thrust load of the roller;
An annular groove provided in one of the end surface on the other end side of the roller and the bearing surface of the bearing member;
In the fluid machine equipped with the annular groove and having an annular seal member that seals between the end surface of the roller and the bearing surface of the bearing member,
The seal member has a U-shaped cross-sectional shape, a seal material including two lip portions that are opposed to each other to form a seal surface, and a heel portion that connects the lip portions, and an inner side of the seal material. A fluid machine comprising: a spring provided; and a protrusion provided on a sliding surface of the lip portion on the side opposite to the groove between the two lip portions. 2. The fluid machine according to claim 1, wherein the groove bottom side of the sealing material is formed in the same plane from the lip part to the heel part. 3. The fluid machine according to claim 1, wherein another member having excellent sliding characteristics is provided between the members that slide relative to each other. The fluid machine according to any one of claims 1 to 3, wherein a tapered portion is formed on an outer peripheral surface of the roller, and a solid lubricating film is formed on a surface of the tapered portion.

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