JP5108664B2 - Scroll type fluid machinery - Google Patents

Description

  The present invention relates to a scroll type fluid machine, and more particularly to a scroll type fluid machine suitable for being incorporated in a refrigeration air conditioner or a heat pump type hot water heater.

This type of scroll type fluid machine, for example, a hermetic scroll compressor, is movable without obstructing the orbiting orbiting motion, and a rotating shaft connected to the orbiting scroll to give the orbiting orbiting motion on the frame of the orbiting scroll relative to the fixed scroll. A rotation preventing mechanism for preventing the scroll from rotating.
The rotation prevention mechanism includes a pin-and-hole type mechanism including a pin projecting from the movable scroll toward the frame and a hole formed in the frame and into which the pin is loosely fitted (for example, see Patent Document 1). ), And a pin and ring type in which the pin is loosely fitted into the hole through the ring is known (for example, see Patent Document 2).
JP 2000-27774 A Japanese Patent No. 3963027

By the way, since the pin is loosely fitted in the hole and can move freely to some extent in the radial direction and the thrust direction of the rotating shaft, there is a concern that the rollover of the movable scroll may be promoted. The overturning of the movable scroll causes a refrigerant leakage from the compression chamber, and there is a problem that the compression efficiency of the compressor is lowered.
In general, the pin is formed from an iron-based material in order to ensure the durability of the rotation prevention mechanism. However, the movable scroll is formed from an aluminum-based material in order to reduce its weight and is likely to be deformed. When the movable scroll is deformed, there is a problem that the relative positional relationship between the pin and the hole is shifted, and the accuracy of the rotation prevention mechanism cannot be ensured.

However, the above-described conventional techniques do not give special consideration to these points.
The present invention has been made in view of such problems, and effectively prevents rollover of the movable scroll and improves its efficiency while facilitating and ensuring the durability and accuracy of the rotation prevention mechanism of the movable scroll. It is an object of the present invention to provide a scroll type fluid machine that can be used.

  In order to achieve the above-mentioned object, the scroll type fluid machine according to claim 1 prevents a revolving orbiting motion and a rotating shaft connected to the orbiting scroll so as to impart a revolving orbiting motion on the frame of the orbiting scroll with respect to the fixed scroll. A scroll type fluid machine having a rotation prevention mechanism that prevents rotation of the movable scroll without rotation, the rotation prevention mechanism being supported on the movable scroll side and projecting toward the frame side, and on the frame side The pin comprises a hole in which the pin is loosely fitted, and the root portion of the pin with which the opening edge of the hole is in contact is positioned substantially on the same plane in the radial direction of the center of gravity of the movable scroll and the rotating shaft. .

According to a second aspect of the present invention, in the first aspect, the movable scroll is made of an aluminum-based material, the pin is made of an iron-based material, and the pin protrudes from a plate made of an iron-based material supported by the movable scroll. The root portion is formed on the plate.
Further, the invention according to claim 3 is characterized in that, in claim 2, the rotation preventing mechanism is characterized in that the pin is loosely fitted inside a cylindrical member made of an iron-based material supported by the frame.

  Therefore, according to the scroll type fluid machine of the first aspect of the present invention, the root portion of the pin with which the opening edge of the hole contacts is substantially flush with the center of gravity of the movable scroll and the radial direction of the rotary shaft. Positioned. Thereby, the distance L in the thrust direction of the rotating shaft between the root portion of the pin and the center of gravity of the movable scroll can be made substantially zero. Here, with the revolution turning motion of the movable scroll 22, a load F that prevents the movable scroll 22 from rotating in the revolution turning direction on the outer periphery of the movable scroll 22 acts on the root portion 46 a. Since the overturning moment M of the movable scroll is a value obtained by multiplying the distance L by the load F, the overturning moment M can also be substantially zero when the distance L becomes substantially zero. The rollover can be effectively prevented and the efficiency of the scroll type fluid machine can be improved.

  According to the second aspect of the invention, the movable scroll is made of an aluminum-based material, the pin is made of an iron-based material, and the pin is projected from a plate made of an iron-based material supported by the movable scroll, The part is formed on a plate. This allows the pin to be firmly fixed to the movable scroll side even when the thickness of the end plate of the movable scroll is reduced because the root portion is positioned substantially on the same plane in the radial direction of the rotary shaft and the center of gravity of the movable scroll. The durability of the rotation prevention mechanism can be ensured.

Moreover, since the pin can be assembled separately from the movable scroll, the positional accuracy of the pin can be improved easily, and the relative positional relationship between the pin and the hole is maintained even if the movable scroll is deformed. The accuracy of the rotation prevention mechanism can be facilitated and ensured.
Further, according to the invention described in claim 3, the rotation preventing mechanism is loosely fitted inside the cylindrical member made of an iron-based material with the pin supported by the frame. As a result, the conventional frame can be used as it is without increasing the thickness of the frame by increasing the thickness of the end plate of the orbiting scroll, and the height of the cylindrical member. Since the hole can be formed separately from the frame by adjusting the position, the position and dimensional accuracy of the hole can be easily increased, and the accuracy of the rotation prevention mechanism can be further facilitated and ensured.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a longitudinal sectional view of a hermetic scroll compressor as an example of a scroll type fluid machine according to the present embodiment.
The compressor 1 is incorporated in a refrigeration circuit such as a refrigeration air conditioner or a heat pump water heater, and the circuit includes a path through which a carbon dioxide refrigerant (hereinafter referred to as a refrigerant), which is an example of a working fluid, circulates. The refrigerant is sucked, compressed, and discharged toward the path.

  The compressor 1 includes a shell 2, and a center shell 4 that forms a cylindrical body of the shell 2 is hermetically fitted with an upper side and a lower side by a top shell 6 and a bottom shell 8, respectively, and the inside of the center shell 4 is hermetically sealed. The discharge pressure of the refrigerant is acting. The center shell 4 is connected to a suction pipe 10 for sucking the refrigerant taken in from the circuit, and a discharge pipe 12 for sending the compressed refrigerant in the shell 2 to the circuit is connected to an appropriate position of the top shell 6. .

In the center shell 4, a scroll unit 14, an electric motor 16, and a pump unit 18 are accommodated in order from the top shell 6 side. A rotating shaft 20 is disposed in the electric motor 16, and the rotating shaft 20 is connected to the electric motor 16. It is rotationally driven by energization of.
The rotary shaft 20 has an upper end connected to the scroll unit 14 and a lower end connected to the pump unit 18, and the rotary shaft 20 is driven to rotate by the electric motor 16, whereby the scroll unit 14 sucks and compresses the refrigerant. And a series of discharge processes.

  Specifically, the scroll unit 14 includes a movable scroll 22 and a fixed scroll 24, and the movable scroll 22 includes an end plate 26 formed of an aluminum material. An end plate surface 26 a of the end plate 26 has an end plate 28 of the fixed scroll 24. On the other hand, a spiral wrap 30 extending toward the end plate 26 is also erected on the end plate surface 28 a of the end plate 28 of the fixed scroll 24.

The wraps 30 and 32 are arranged in pairs and cooperate with each other, so that the refrigerant is sucked from the refrigerant suction chamber formed in the end plate 28 through the suction pipe 10 and is interposed between the wraps 30 and 32. A compression chamber is formed, and the compression chamber moves toward the center of the end plates 26 and 28 while reducing its volume.
In order to give the orbiting scroll 22 a revolving orbiting motion, a boss 34 is formed on the back surface 22b side of the end plate 26, and the boss 34 is rotatable about an eccentric shaft 36 integrally formed on the upper end side of the rotary shaft 20 via a bearing. It is supported by.

On the other hand, the fixed scroll 24 is supported and fixed to a main frame (frame) 38 fixed inside the center shell 4, and a discharge hole 40 communicating with the compression chamber is formed in the central portion of the fixed scroll 24. Has been.
On the other hand, the pump unit 18 sucks the lubricating oil stored inside the bottom shell 8, and the sucked lubricating oil passes through an oil passage 42 formed in the rotating shaft 20 from the upper end of the rotating shaft 20 to the electric motor. 16 and the scroll unit 14 and the like, and contributes to the lubrication of each sliding part and bearing, and the sealing and lubrication of the sliding surface.

  According to the compressor 1 described above, the movable scroll 22 revolves without rotating on the pedestal surface 38 a of the main frame 38 as the rotary shaft 20 rotates, so that the scroll unit 14 is connected via the suction pipe 10. The refrigerant sucked into the compression chamber forms a compression chamber. The refrigerant in the compression chamber is compressed while being moved toward the center of the scroll unit 14, and then discharged into the shell 2 through the discharge hole 40 and circulated in the shell 2. It is sent out of the compressor 1 through the discharge pipe 12.

By the way, the rotation of the movable scroll 22 is blocked by the rotation blocking mechanism 44.
As shown in the enlarged sectional view of the rotation prevention mechanism 44 in FIG. 2, the rotation prevention mechanism 44 is supported on the movable scroll 22 side and protrudes toward the frame 38, and the pin 46 is provided on the frame 38 side. It is comprised from the cylindrical member (hole) 48 loosely fitted.
The pin 46 and the cylindrical member 48 are made of an iron-based material, and the pin 46 protrudes from a ring-shaped plate 50 that is also made of an iron-based material, and is supported on the movable scroll 22 side via the plate 50. Yes.

Specifically, the plate 50 is embedded in a step portion 22c with the back surface 22b formed by reducing the thickness of the outer peripheral portion of the end plate 26, and is strictly positioned and fixed to the movable scroll 22 by a fixing pin (not shown). .
The cylindrical member 48 is strictly positioned and fixed at a position corresponding to the pin 46 of the frame 38.
And the base part 46a of the pin 46 with which the upper end surface (opening edge part) 48a of the cylindrical member 48 contacts is formed in the projecting surface 50a by which the pin 46 of the plate 50 protrudes, and the base part 46a and the movable scroll are formed. The center of gravity 52 of 22 is positioned on substantially the same surface 54 (indicated by a dotted line) in the radial direction of the rotary shaft 20. The surface 54 is substantially parallel to the end plate surface 26 a of the movable scroll 22.

  As shown in the perspective view of the movable scroll 22 in FIG. 3, for example, six pins 46 are strictly positioned and fixed at equal intervals along the outer circumferential direction of the plate 50, and these pins 46 are attached to the frame. The rotation prevention mechanism 44 that is loosely fitted inside the six cylindrical members 48 that are positioned and fixed, and configured as described above, realizes a smooth revolving motion with respect to the fixed scroll 24 while preventing the rotation of the movable scroll 22. .

Hereinafter, with reference to an enlarged cross-sectional view of the conventional movable scroll 22 shown in FIG. 4, the generation principle of the rollover moment M acting in the direction to roll over the movable scroll 22 will be described.
Along with the revolution turning motion of the movable scroll 22, a load F that prevents the rotation of the movable scroll 22 acts on the root portion 46 a in the revolution turning direction on the outer periphery of the movable scroll 22.
The root portion 46 a and the surface 54 are separated from each other by a distance L in the thrust direction of the rotary shaft 20, and a rollover moment M obtained by multiplying the distance L by a load F acts in a direction to roll over the movable scroll 22.

On the other hand, referring to the enlarged cross-sectional view of the movable scroll 22 of the present embodiment shown in FIG. 5, even if the load F acts on the root portion 46a, the overturning moment M is also substantially zero as the acting distance L becomes substantially zero. It becomes.
As described above, in the present embodiment, since the root portion 46a and the center of gravity 52 are positioned on substantially the same surface 54 in the radial direction of the rotating shaft 20, the distance L can be made substantially zero. Even if the load F acts on the root portion 46a, the rollover moment M can be made substantially zero, the rollover of the movable scroll 22 can be effectively prevented, and the compression efficiency of the compressor 1 can be improved.

  The movable scroll 22 is made of an aluminum-based material, the pin 46 is made of an iron-based material, the pin 46 protrudes from a plate 50 made of an iron-based material supported by the movable scroll 22, and the root portion 46 a is a plate 50. Formed on top. Thereby, even if the thickness of the end plate 26 of the movable scroll 22 becomes thin because the root portion 46a is positioned on the same plane as the surface 54, the pin 46 can be firmly fixed to the movable scroll 22 side, and the rotation prevention mechanism The durability of 44 can be ensured.

Moreover, since the pin 46 can be assembled separately from the movable scroll 22, the positional accuracy of the pin 46 can be easily increased, and even if the movable scroll 22 is deformed, the pin 46 and the cylindrical member 48 The relative positional relationship can be maintained, and the accuracy of the rotation prevention mechanism 44 can be easily secured.
Further, the rotation prevention mechanism 44 is configured by loosely fitting the pin 46 inside the cylindrical member 48, so that the thickness of the end plate 26 of the movable scroll 22 is increased, so that the thickness of the frame 38 is increased. Thus, the conventional frame 38 can be used as it is without being raised.

Further, since the hole in the case of the pin & hole type rotation prevention mechanism can be formed separately from the frame 38 by adjusting the height of the cylindrical member 48, the position and dimensional accuracy of the hole can be easily increased. The accuracy of the rotation prevention mechanism 44 can be further facilitated and ensured.
The description of one embodiment of the present invention is finished above, but the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

  For example, in the above embodiment, a hermetic scroll compressor using a carbon dioxide refrigerant incorporated in a refrigeration circuit such as a refrigeration air conditioner or a heat pump type hot water heater has been described. However, the present invention is not limited thereto, and various operations are performed. The present invention is applicable to a scroll type fluid machine using a fluid such as a compressor or an expander in various fields.

1 is a longitudinal sectional view showing a hermetic scroll compressor according to an embodiment of the present invention. FIG. 2 is an enlarged cross-sectional view showing the rotation prevention mechanism of FIG. 1. It is the perspective view which showed the movable scroll of FIG. It is an expanded sectional view of the movable scroll which showed the generating principle of the overturning moment in the conventional movable scroll. It is an expanded sectional view of the movable scroll which showed the overturning moment of the movable scroll of FIG.

Explanation of symbols

1 Hermetic scroll compressor (scroll type fluid machine)
20 Rotating shaft 22 Movable scroll 24 Fixed scroll 38 Main frame (frame)
44 Rotation prevention mechanism 46 Pin 46a Root part 48 Cylindrical member (hole)
50 plates 52 center of gravity 54 surfaces

Claims (3)

A rotating shaft connected to the movable scroll to give a revolving orbiting motion on the frame of the movable scroll with respect to the fixed scroll, and a rotation prevention mechanism for preventing the rotation of the orbiting scroll without preventing the orbiting orbiting motion. A scroll type fluid machine,
The rotation prevention mechanism includes a pin supported on the movable scroll side and projecting toward the frame side, and a hole in which the pin is loosely fitted on the frame side,
The scroll fluid machine according to claim 1, wherein a base portion of the pin with which an opening edge portion of the hole comes into contact is positioned on substantially the same plane in the radial direction of the rotary shaft and the center of gravity of the movable scroll. The movable scroll is made of an aluminum-based material, and the pin is made of an iron-based material.
The scroll type fluid machine according to claim 1, wherein the pin protrudes from a plate made of an iron-based material supported by the movable scroll, and the root portion is formed on the plate.   The scroll type fluid machine according to claim 2, wherein the rotation prevention mechanism is configured such that the pin is loosely fitted inside a cylindrical member made of an iron-based material supported by the frame.

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