JPH0979148A - Scroll type fluid machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce surface pressure of its key groove and an Oldham's key of an Oldham's ring without enlarging a diameter and a thickness of a movable scroll. SOLUTION: A swelling slidingly movable part 36 to expand the slidingly movable area with an Oldham's key 72 of an Oldham's ring 7 in the shaft direction, is extendedly arranged in a key groove forming part of an end plate 31 in a movable scroll 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a movable scroll used in a scroll type fluid machine.

[0002]

2. Description of the Related Art Conventionally, a scroll type fluid machine is disclosed in, for example, Japanese Patent Application Laid-Open No. 2-91488, and as shown in FIG.
1, a fixed scroll B formed by projecting a spiral body B2 and a movable scroll C formed by similarly projecting a scroll body C2 on an end plate C1 are combined in a vertically opposed manner to be supported on a frame D, and the casing A The motor E is disposed on the lower inner side of the motor E, and the eccentric shaft portion F1 of the drive shaft F coupled to the motor E is
Is linked to the movable scroll C, and the movable scroll C is connected between the movable scroll C and the frame D.
It is equipped with an Oldham ring G that blocks the rotation of the. Then, the rotation of the drive shaft F following the drive of the motor E causes the Old scroll to rotate around the movable scroll C by the Oldham ring G while revolving the movable scroll C with respect to the fixed scroll B. Scroll B,
The suction fluid is compressed in the compression chamber formed between the spiral bodies B2 and C2 of C.

The Oldham ring G is composed of a ring body G1 having a central hole G0.
A pair of first keys G2 and G2 facing each other and the respective keys G
A pair of second keys G3 and G3 orthogonal to 2 and G2 are provided so as to project. Further, in the movable scroll C, the first keys G2 are provided on the outer peripheral portions of the end plate C1 facing each other.
The fixed scroll B is provided with a pair of key grooves C3 for receiving the second keys G3, and the fixed scroll B is provided with a pair of key grooves B3 for receiving the second keys G3. G2 and G3 are slidably engaged with each other to prevent the movable scroll C from rotating when the drive shaft F rotates, and revolve the movable scroll C with respect to the fixed scroll B. .

[0004]

In the above scroll type fluid machine, in order to efficiently orbit the movable scroll C, the key groove C3 formed in the movable scroll C and the Oldham ring G are projected. It is necessary to minimize the surface pressure between the first key G2 and the first key G2. However, in the above-mentioned conventional configuration, the key groove C3 of the movable scroll C is formed in the outer peripheral portion of the end plate C1 to have the same depth as the vertical thickness of the end plate C1, and also protrudes from the Oldham ring G. The first key G2 is
Since the upper and lower depths of the key groove C3 are formed to be substantially the same as or slightly lower than the depth, the key groove C3 and the first key G are formed.
The contact area with 2 is small, and the surface pressure between the two is large.

Therefore, in order to reduce the surface pressure between the key groove C3 and the first key G2, the first key G2 is extended in the radial direction, and the key groove with which the first key G2 is engaged. The key groove C3 is formed by extending C3 radially outward.
It is conceivable to increase the contact area between the movable scroll C and the first key G2. However, in this case, since the end plate C1 of the movable scroll C in which the key groove C3 is formed needs to have a large diameter, the movable scroll C The processing range of the thrust receiving surface for the frame D is increased, which makes the processing complicated, and by making the movable scroll C large in diameter, the scroll type fluid machine becomes large in the radial direction, and the outer diameter thereof increases. There is a problem that the degree of freedom in design is reduced when is restricted.

In order to reduce the surface pressure, the thickness of the end plate C1 is increased to increase the depth of the key groove C3, and the first key G2 engaging with the key groove C3.
It is conceivable that the contact area between the key groove C3 and the first key G2 may be increased by increasing the height of the key groove C3, but in such a case, by increasing the thickness of the end plate C1,
Since the weight of the movable scroll C is significantly increased, the degree of freedom in the balance design is reduced.

The main object of the present invention is to reduce the surface pressure between the key groove and the Oldham key of the Oldham ring without increasing the diameter and thickness of the movable scroll, so as to efficiently orbit the movable scroll. The point is to be able to do.

[0008]

Therefore, according to the invention described in claim 1, as shown in FIGS. 1 and 2, a fixed scroll 2 and a movable scroll in which scrolls 22 and 32 are respectively provided on end plates 21 and 31 so as to project. And a key groove 35 slidably engaged with the Oldham key 72 on the outer side in the radial direction of the end plate 31 of the movable scroll 3.
In addition to the above, a bulging sliding portion 36 that extends the sliding area with the Oldham key 72 in the axial direction is provided at the key groove forming portion of the end plate 31.

According to this structure, the sliding area of the Oldham key 72 with respect to the key groove 35 can be increased by the axially bulging sliding portion 36 provided in the portion of the end plate 31 where the key groove 35 is formed. Because you can, this Oldham Key 7
The surface pressure of 2 can be reduced, and efficient revolving drive of the movable scroll can be performed. Moreover, since the surface pressure of the Oldham key 72 can be reduced without increasing the diameter and thickness of the movable scroll, there is no inconvenience in designing a scroll fluid machine including the movable scroll.

According to a second aspect of the present invention, in the first aspect of the present invention, since the bulging sliding portion 36 is formed so as to extend toward the side opposite to the spiral body 32, the sliding portion is located on the side of the spiral body 32. 36
The sliding portion 36 does not act as a resistance to the suction gas sucked into the suction passage between the scroll 32 of the movable scroll and the scroll of the fixed scroll as in the case of forming The center of gravity of the movable scroll can be moved to the anti-spiral body 32 side by the portion 36. Therefore, the balance weight arranged on the anti-spiral body 32 side for achieving the static balance and dynamic balance of the movable scroll. Can be made smaller.

According to a third aspect of the invention, in the second aspect of the invention, as shown in FIG. 6, the spiral body 3 of the end plate 31.
Since the thrust pressing surface 37 is formed on the second side, the movable scroll can be favorably thrust-supported by the pressing surface 37. That is, the end plate 3 in this movable scroll
When the bulging sliding portion 36 is provided on the side of the spiral body 32 of No. 1, the sliding portion 36 becomes an obstacle and it becomes difficult to support thrust on the fixed scroll side of the movable scroll. By forming the sliding portion 34 on the side opposite to the spiral body 32, the pressing surface 37 can be formed on the side of the spiral body 32, and the thrust surface of the movable scroll can be favorably supported by the pressing surface 37. You can

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a scroll type fluid machine according to the present invention, in which a fixed scroll 2 formed by projecting a spiral body 22 on an end plate 21 on the upper inner side of a hermetic casing 1,
Similarly, a movable scroll 3 formed by projecting a spiral body 32 on the end plate 31 is vertically opposed to each other to be supported by a frame 4, and a motor 5 is arranged on the inner lower side of the casing 1. The upper end side eccentric shaft portion 61 of the drive shaft 6 which is connected to the frame 5 and is supported by the frame 4 is inserted into and supported by the boss portion 33 provided at the center of the lower surface of the movable scroll 3, while the movable scroll 3 and An Oldham ring 7 is inserted between the frame 4 and the movable scroll 3 so as to prevent the rotation of the movable scroll 3 and revolve.

As shown in FIGS. 2 and 3, the Oldham ring 7 is composed of a ring body 71 having a central hole 70. The ring body 71 has a pair of first Oldham keys facing each other on the upper side thereof. 72 and 72 are projected, and a pair of second Oldham keys 73 and 73 are projected on the lower side in a direction orthogonal to the respective Oldham keys 72.

Further, the movable scroll 3 is shown in FIG.
As is apparent from FIG. 4, arms 34, 34 projecting outward in the radial direction are integrally provided at outer peripheral portions of the end plate 31 facing each other, and the first Oldham keys 72 are received in the arms 34. As shown in FIG. 2, on the surface of the frame 4 facing the Oldham ring 7, as well as forming the substantially U-shaped key grooves 35, 35 having open ends.
A pair of keyways 4 for receiving the respective second Oldham keys 73.
0 are provided to face each other, and the Oldham keys 72 and 73 of the Oldham ring 7 are slidably engaged with the key grooves 35 and 40, respectively, so that the movable scroll 3 of the movable scroll 3 is rotated when the drive shaft 6 rotates. The movable scroll 3 is revolved around the fixed scroll 2 while preventing rotation.

Further, a partition body 8 is provided inside the casing 1 on the upper side of the fixed scroll 2, and a discharge port 23 provided on the fixed scroll 2 is opened on the upper side of the partition body 8. A high pressure chamber 12 is formed in which an external discharge pipe 11 for discharging the discharge gas to the outside of the casing 1 is opened, and a low pressure chamber 14 in which a suction pipe 13 is opened is formed on the lower side of the frame 4. are doing.

Then, the drive shaft 6 is rotated in accordance with the drive of the motor 5, and the Oldham ring 7 prevents the movable scroll 3 from rotating while the movable scroll 3 is rotated.
By orbiting the fixed scroll 2 to introduce the gas introduced from the suction pipe 13 into the low-pressure chamber 14 from the gas passage 41 provided in the frame 4 between the scrolls 2 and 3. 15 to the scroll body 2 of the scrolls 2 and 3 through the suction passage 15.
The compressed gas is sucked into a compression chamber formed between No. 2 and 32, the suction gas is compressed in the compression chamber, and then the compressed gas is discharged from the discharge port 23 to the high pressure chamber 12 and discharged from the discharge pipe 11 to the outside. Of.

Therefore, in the above structure, as shown in FIGS. 1 to 4, each arm portion 34 in which each key groove 35 is formed in the end plate 31 of the movable scroll 3 is attached to the arm portion 34 of the Oldham ring 7. 1 The bulging sliding portions 36 are formed to expand the sliding area with the Oldham key 72 in the axial direction. More specifically, on both sides of the arm portion 34 that sandwich the key groove 35, the arm grooves 34 are flush with the contact surfaces 35a, 35a of the key groove 35 with the Oldham key 72, and the side on which the spiral body 32 is formed. A pair of bulging sliding portions 36, 36 bulging downward are integrally provided on the side opposite to the above, and the vertical height of the first Oldham key 72 is set to the sliding portions 3
It is formed so that it can be inserted across 6 and the key groove 35.

As described above, the keyway 3 is formed in each of the arm portions 34.
5, the respective sliding portions 36 are formed integrally with each other so as to be flush with each other, and the first Oldham key 72 is connected to the sliding portions 36 and the key groove 35.
Since the sliding area of the first Oldham key 72 with respect to the key groove 35 is increased by forming the height so that the first Oldham key 72 can be inserted over the key groove 35, the surface pressure of the first Oldham key 72 is reduced and the movable area is reduced. The orbital drive of the scroll 3 can be efficiently performed. Moreover, since the surface pressure of the Oldham key 72 can be reduced without increasing the diameter or thickness of the movable scroll 3, the working range of the thrust receiving surface of the movable scroll 3 with respect to the frame 4 can be increased, or the movable scroll can be moved. There is no inconvenience in designing a scroll type fluid machine including the scroll 3.

When the sliding portion 36 is provided on the upper side where the scroll 32 is formed, the sliding portion 36 is provided between the gas passage 41 of the frame 4 and the suction passages between the scrolls 2 and 3. While it becomes the resistance of the inhaled gas reaching 15,
Since the sliding portion 36 is formed so as to bulge on the lower side opposite to the spiral body 32, the sliding portion 36 does not serve as a resistance to the intake gas, and the sliding portion 36 is provided. As a result, the position of the center of gravity of the movable scroll 3 moves to the lower side, and as a result, the balance weights 91 and 92 provided on the drive shaft 6 and the like for achieving the static balance and dynamic balance of the movable scroll 3 are reduced. it can.

Further, since the bulging sliding portion 36 is formed not on the upper side of the end plate 31 of the movable scroll 3 but on the lower side of the end plate 31, the sliding part 36 becomes an obstacle. Instead, the movable scroll 3 can be thrust-supported on the fixed scroll 2 side. That is, as shown in FIG. 6, the thrust which makes the lower peripheral portion side of the end plate 21 of the fixed scroll 2 contact the upper surface side of the end plate 31 of the movable scroll 3 without being affected by the sliding portion 36. Since the pressing surface 37 can be formed, the pressing scroll 37 can favorably support the movable scroll 3 in the thrust direction.

[0021]

As described above, according to the first aspect of the present invention, the key groove is formed by the axially bulging sliding portion 36 provided at the portion where the key groove 35 is formed in the end plate 31 of the movable scroll. Since the sliding area of the Oldham key 72 with respect to 35 can be increased, the surface pressure of the Oldham key 72 can be reduced, and the orbiting of the movable scroll can be efficiently performed. Moreover, since the surface pressure of the Oldham key 72 can be reduced without increasing the diameter and thickness of the movable scroll, there is no inconvenience in designing a scroll fluid machine including the movable scroll.

According to the second aspect of the present invention, since the bulging sliding portion 36 is formed to extend toward the side opposite to the spiral body 32,
The sliding portion 36 can move the position of the center of gravity of the movable scroll to the side opposite to the spiral body 32 without the sliding portion 36 becoming a resistance to the intake gas. Therefore, the static balance and movement of the movable scroll can be improved. The balance weight provided on the side opposite to the spiral body 32 for balancing can be made small and lightweight.

According to the invention of claim 3, the end plate 3
By forming the thrust pressing surface 37 on the side of the spiral body 32 of No. 1, the movable scroll can be thrust-supported on the fixed scroll side. At this time, the pressing scroll 37 can favorably support the movable scroll.

[Brief description of drawings]

FIG. 1 is a 90 ° vertical sectional view of a compressor provided with a movable scroll according to the present invention.

FIG. 2 is a vertical cross-sectional view of the main part.

FIG. 3 is a plan view of the orbiting scroll.

FIG. 4 is a vertical sectional view thereof.

FIG. 5 is a sectional view of an Oldham ring.

FIG. 6 is a vertical cross-sectional view showing another embodiment.

FIG. 7 is a longitudinal sectional view showing a conventional example.

[Explanation of symbols]

 2 ... Fixed scroll 21 ... End plate 22 ... Spiral member 3 ... Movable scroll 31 ... End plate 32 ... Spiral member 35 ... Key groove 36 ... Bulging sliding portion 37 ... Thrust pressing surface 72 ... Oldham key

Claims (3)

[Claims] 1. A spiral body (22) on an end plate (21) (31)
A scroll-type fluid machine comprising a fixed scroll (2) and a movable scroll (3) each having a protruding (32), wherein an Oldham key is provided outside the end plate (31) of the movable scroll (3) in the radial direction. A key groove (35) slidably engaged with (72) is formed, and the end plate (31) is formed.
2. A scroll type fluid machine, characterized in that a bulging sliding portion (36) that axially expands the sliding area with the Oldham key (72) is provided in the key groove forming portion of the above. 2. A bulging sliding portion (36) is provided with an anti-spiral member (32).
The scroll type fluid machine according to claim 1, which is extended to the side. 3. The scroll type fluid machine according to claim 2, wherein a thrust pressing surface (37) is provided on the scroll body (32) side of the end plate (31).