JP6636304B2 - Scroll compressor - Google Patents

Description

  The present invention relates to a scroll compressor having two spiral walls.

2. Description of the Related Art A double scroll compressor having two independent spiral wall bodies on an end plate is known (see Patent Literature 1 and Patent Literature 2). The double scroll compressor has the advantage that the suction volume can be increased, but this has the problem that the design volume ratio (design pressure ratio) decreases and the efficiency decreases under operating conditions with a large pressure ratio.
On the other hand, as shown in Patent Document 3, there is known a scroll compressor in which a step is provided in the middle of a spiral wall body to change the height and perform three-dimensional compression including compression in the height direction. ing. The scroll compressor that performs such three-dimensional compression can increase the design volume ratio (design pressure ratio) as compared to two-dimensional compression in which the height of the spiral wall is not changed. .

JP-A-3-67082 JP-A-8-210268 JP-A-2002-364560

However, when a structure for performing the above-described three-dimensional compression is applied to the above-described two-row scroll compressor, it is difficult to form a compression chamber. This is because, in the single-row scroll, there is a phase difference of 180 ° between the inside and outside of the spiral wall, and the shape of the step at the bottom corresponding to the locus circle of the step of the spiral wall is semicircular (180 °). And that the compression chamber could be formed.
On the other hand, in the double scroll, since the phase difference between the inside and the outside of the spiral wall is 90 °, it does not coincide with the locus circle (180 °) of the step portion, and it is fundamentally difficult to form a compression chamber. The problem existed. This point will be described later with reference to FIGS.

  The present invention has been made in view of such circumstances, and has a structure in which a compression chamber is formed and compressed even in a structure having two spiral walls and performing three-dimensional compression. It is an object of the present invention to provide a scroll compressor capable of performing the following.

In order to solve the above problems, the scroll compressor of the present invention employs the following means.
In other words, the scroll compressor according to the present invention has a spiral wall having two spiral walls formed of a first wall body and a second wall body provided on one side surface of an end plate, and is fixed at a fixed position. The scroll has a spiral-shaped third wall and a two-walled wall composed of a fourth wall erected on one side surface of the end plate. The first wall and the second wall are formed with respect to the first wall and the second wall. A third scroll and a revolving scroll supported so as to be capable of revolving orbit while being prevented from rotating in a state where the third wall and the fourth wall are engaged with each other, wherein the first wall and the second wall are separated from each other. It is arranged at a point symmetric position rotated by 180 ° with the center of the spiral in common, and the third wall and the fourth wall have the same shape as the first wall and the second wall, respectively. The fixed scroll and the orbiting scroll are engaged with each other with a phase difference of 90 °. In each of the fixed scroll and the orbiting scroll, the bottom on the end plate side corresponding to the winding end position on the outer peripheral side of each of the wall bodies that shuts off by suctioning fluid has a higher height at the center side than the outer peripheral side. By having a bottom side step portion, and having a wall side step portion in which the tip in the height direction of each of the wall members meshing with the bottom side step portion is lower at the center side than at the outer peripheral side , at the time of suction cutoff It is characterized in that the formed compression chamber is compressed while maintaining the compression chamber at all turning angles without being opened .

  The present inventors have conducted intensive studies, and as a result, in a double-row scroll meshed with a phase difference of 90 °, a bottom side step is provided at a bottom corresponding to a winding end position of a wall body which sucks fluid and shuts off, and It has been found that, when the wall-side step is provided at a position where it meshes with the bottom-side step, the compression chamber formed at the time of suction cutoff can be compressed while maintaining the compression chamber at all turning angles without being opened. This makes it possible to achieve three-dimensional compression in which the height of the wall is added to the double scroll, thereby increasing not only the suction volume but also the design volume ratio (design pressure ratio). Can be.

  Even in a structure having two spiral walls and performing three-dimensional compression, a compression chamber can be formed and compressed. Thus, not only the suction volume but also the design volume ratio (design pressure ratio) can be increased.

FIG. 2 is a plan view showing a fixed scroll according to one embodiment of the present invention. It is the top view which showed the orbiting scroll which concerns on one Embodiment of this invention. FIG. 3 is a plan view showing a state where the fixed scroll of FIG. 1 and the orbiting scroll of FIG. 2 are engaged with each other. FIG. 4 is an enlarged schematic view of a meshing step B of FIG. 3. FIG. 4 is a plan view showing a state where the vehicle is turned 90 ° from the meshing state of FIG. 3. 5 is a timing chart showing a sealable range of a meshing step A and a meshing step B. FIG. 4 is a plan view sequentially showing the meshing state shown in FIG. 3 for each turning angle. FIG. 9 is a plan view showing a meshing state of Comparative Example 1. FIG. 9 is an enlarged schematic diagram illustrating a meshing step portion A ′ in FIG. 8. FIG. 9 is a plan view showing a state where the vehicle is turned 90 ° from the meshing state in FIG. 8. FIG. 9 is a plan view showing a meshing state of Comparative Example 2. It is the schematic diagram which expanded and showed the meshing step part A "of FIG. FIG. 12 is a plan view showing a state where the vehicle is turned 90 ° from the meshing state of FIG. 11.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
The scroll compressor of the present embodiment compresses a gas (fluid) and is not particularly limited. For example, when the scroll compressor is used as a compressor of a supercharger attached to an engine, the scroll air is compressed. It compresses and compresses refrigerant when used as a compressor of a vapor compression refrigerator.

  FIG. 1 shows a fixed scroll 1 and FIG. In the present embodiment, the wall portion of the fixed scroll 1 is hatched in order to facilitate the distinction between the fixed scroll 1 and the orbiting scroll 2. Both scrolls 1 and 2 are made of an aluminum alloy or an iron-based metal. Although the outlines of the end plates 6 and 7 are not shown in the drawing, the end plates 6 and 7 are generally formed in a circular shape larger than the diameter surrounding the entire wall.

The fixed scroll 1 is fixed at a fixed position so as not to move relative to, for example, a compressor housing. As shown in FIG. 1, the fixed scroll 1 includes a spiral first wall 3 and a second wall 4 erected on one side surface of an end plate 6.
A discharge port 5 for discharging the compressed gas to the outside is formed at the center of the end plate 6.

  The first wall body 3 is adjacent to the outer edge of the discharge port 5 and has a winding start 3a at a position substantially at 9 o'clock in FIG. ing. The position of the winding end 3b of the first wall body 3 is set at about 5:00 in FIG. 1 which is slightly more than one turn (360 °) and 1/4 turn from the winding start 3a. The shape of the inner peripheral surface and the outer peripheral surface of the first wall 3 is formed by, for example, an involute curve. However, the winding start portion 3a of the first wall 3 is formed using various curves.

  A wall-side step 3c is provided at a position 90 ° from the winding end 3b of the first wall 3 toward the center (clockwise in the drawing). The wall-side step 3c is a step in which the tip (so-called tooth tip) in the height direction is lower on the center side than on the outer peripheral side. That is, the height from the winding end 3b to the wall-side step 3c is constant (H1), and the height of the step 3c changes so as to decrease in the direction perpendicular to the sheet of FIG. The height (H2) is constant up to the winding start 3a. Therefore, the relationship between the heights H1 and H2 from the end plate 6 is H1> H2. The wall-side step 3c has a semicircular cross-section that is convex in the winding direction (clockwise in the figure) toward the center of the first wall 3 when viewed in a plan view as shown in FIG. are doing. The wall-side step 3c meshes with the bottom-side step 10d (see FIG. 2) of the orbiting scroll 2 as described later.

  A bottom step 3d is provided at the bottom of the first wall 3 at the end plate 6 side at the winding end 3b. The bottom side step 3d is a step whose height is higher at the center side than at the outer peripheral side. That is, when viewed from the tooth tip of the first wall 3, the tooth bottom is deep on the outer peripheral side of the bottom-side step 3d, and is shallow on the center side of the bottom-side step 3d. The bottom-side step 3d has a semicircular cross-section that is convex in the direction toward the center (clockwise in the figure) when viewed in a plan view as shown in FIG. The semicircular arc is provided so as to be in contact with the edge 3d1 of the inner wall of the winding end 3b and the connection point 3d2 of the outer wall of the second wall 4 located on the spiral center O1 side with respect to the edge 3d1. . The radius of the semicircular arc of the bottom side step 3d is a size corresponding to the turning radius of the orbiting scroll 2. As will be described later, the bottom-side step 3d is adapted to mesh with the wall-side step 11c (see FIG. 2) of the orbiting scroll 2.

  The second wall 4 has the same spiral center as the spiral center O1 of the first wall 3, and is disposed at a point symmetrical position where the first wall 3 is rotated by 180 ° around the spiral center O1. Therefore, the winding start 4a is located at the point symmetrical position of the winding start 3a of the second wall 4, and the wall side step 4c is located at a position 90 ° central side from the winding end 4b similarly to the first wall 3. And a bottom side step 4d at the position of the winding end 4b.

  The orbiting scroll 2 is supported to be capable of revolving orbiting while being prevented from rotating in a state of being engaged with the fixed scroll 1. For example, although not shown, a shaft that is rotationally driven with respect to a boss provided at a center position on a surface opposite to one side surface of the end plate 7 of the orbiting scroll 2 on which the wall bodies 10 and 11 are erected. Is connected to the crank pin provided at the end of the first pin. The crank pin is eccentric from the center axis of the shaft by a predetermined amount, and this eccentric amount becomes the turning radius of the orbiting scroll 2. There are various drive sources for the shaft, but when a scroll compressor is used as a supercharger, power taken out by an exhaust turbine is used, and when used as a compressor for a refrigerator, power from an electric motor is used. In the case of a car air conditioner of an engine driven vehicle, power from an engine is used.

As shown in FIG. 2, the orbiting scroll 2 includes a spiral third wall body 10 and a fourth wall body 11 erected on one side surface of the end plate 7. The third wall 10 and the fourth wall 11 have the same shape as the first wall 3 and the second wall 4 of the fixed scroll 1. However, the orbiting scroll 2 shown in FIG. 2 is shown in a state where it is rotated 90 ° clockwise with respect to the fixed scroll 1 shown in FIG. This corresponds to the positional relationship when the fixed scroll 1 and the orbiting scroll 2 are engaged (see FIG. 3).
Therefore, similarly to the first wall 3, the third wall 10 includes a winding start 10a, a winding end 10b, a wall-side step 10c, and a bottom-side step 10d. Like the second wall 4, the fourth wall 11 also includes a winding start 11a, a winding end 11b, a wall-side step 11c, and a bottom-side step 11d. Similarly to the positional relationship between the first wall 3 and the second wall 4, the fourth wall 11 has the same spiral center as the spiral center O2 of the third wall 10, and the third wall 10 Are rotated by 180 ° around the spiral center O2.

FIG. 3 shows a state in which the fixed scroll 1 of FIG. 1 and the orbiting scroll 2 of FIG. 2 are engaged. That is, the fixed scroll 1 and the orbiting scroll 2 are engaged with each other with a phase difference of 90 °. The orbiting scroll 2 orbits the fixed scroll 1 clockwise when viewed in a plan view as shown in FIG.
In the state shown in FIG. 3, the wall-side step 3c of the first wall 3 of the fixed scroll 1 and the bottom-side step 10d of the third wall 10 of the orbiting scroll 2 mesh at the mesh start point A1 to start sealing. Then, the state at the time of the suction cutoff in which the gas is suctioned and closed at the winding end 10b of the third wall body 10 is shown. That is, since the bottom side step 10d of the orbiting scroll 2 is provided at a position corresponding to the winding end 10b of the third wall body 10, the wall body side step part 3c and the bottom side step part 10d are engaged at the time of the suction cutoff. , Forming a closed compression space. (Hereinafter, the meshing portion between the wall-side step 3c and the bottom-side step 10d is referred to as "meshing step A".)

  The compression space S1 partitioned at the meshing start point A1 is formed to the meshing position C1 further advanced 360 ° toward the center. Then, in the compression space S1, there is an engaging step B in which the bottom-side step 4d of the second wall 4 of the fixed scroll 1 and the wall-side step 10c of the third wall 10 of the orbiting scroll 2 engage. Will be. As is clear from the fact that the wall-side step 10c and the bottom-side step 10d of the third wall 10 are installed at an angle of 90 ° around the spiral center O2 (see FIG. 2), the meshing step B is provided at an angle of 90 ° around the spiral centers O1 and O2 with respect to the meshing step A. As a result, since the orbiting scroll 2 orbits clockwise in FIG. 3, the meshing step B has a phase advanced by 90 ° from the meshing step A, and as shown in FIG. And the seal end point B2, and at an intermediate position B3 which is 90 ° ahead of the seal start point B1. Further, since the wall-side step 10c relatively moves to the seal end point B2 while maintaining the mesh with the bottom-side step 4d, the state of FIG. Leak-free meshing is performed.

  FIG. 5 shows a state in which the turning angle has advanced by 90 ° from FIG. As can be seen from the figure, in the meshing step B, the wall-side step 10c is located at the seal end point B2 (see FIG. 4). After this timing, the compression space S1 passes through the mesh step B, so that even if the mesh is disengaged at the mesh step B and leakage occurs, the compression space S1 is not affected. . The compression space S <b> 1 is further moved to the center by further compression. However, since the compression space S <b> 1 has already passed through the meshing step A and the meshing step B, the occurrence of leakage due to the meshing steps A and B occurs. The compression is continued until the discharge port 5 is reached.

FIG. 6 is a timing chart showing a range sealed by the meshing steps A and B. In the figure, the horizontal axis indicates the turning angle.
The installation angle between the meshing step A and the meshing step B is 90 ° around the spiral centers O1 and O2 as described above. Then, the sealable range of the meshing step A is 180 ° because the wall side step 3c meshes with the bottom step 10d having a semicircular (180 °) cross section. Similarly, the sealable range of the meshing step B is 180 ° because the angle range in which the wall-side step 10c meshes with the bottom-side step 4d having a semicircular (180 °) cross section.
Then, when the suction cutoff angle is reached, the seal at the meshing step A has been completed, but the meshing start point A1 (see FIG. 3) forming the compression space S1 passes through the meshing step A. Immediately after, the seal state at the meshing step A is not affected. During the subsequent 90 ° turning angle, the sealing of the meshing step B is continued, so that the compression space S1 is maintained without leakage. After the meshing position of the compression space S1 has passed through the setting angle of the meshing step B, as described above, since there is no meshing step in the region of the compression space S1, compression without leakage continues. Is done.

3 to 6, the state of the specific compression space S1 has been described. However, since the walls 3 and 4 of the fixed scroll 1 and the walls 10 and 11 of the orbiting scroll 2 have the same shape, the same applies to other compression spaces. Becomes
Therefore, as shown in FIG. 7, the fixed scroll 1 and the orbiting scroll 2 can be successively compressed without gas leakage from the suction cutoff. In the figure, compression is performed in the order of (a) → (b) → (c) → (d) → (e) → (f) → (g) → (h) → (a). The state shown in FIG. 3 corresponds to FIG. 7 (e), and the state shown in FIG. 5 corresponds to FIG. 7 (g).

  As described above, in the present embodiment, in the case of the scroll compressor having the double-row scroll, the scroll compressor is set at the position corresponding to the winding end 3b, 4b, 10b, 11b of the wall body 3, 4, 10, 11 serving as the suction cutoff position. Compressed space S1 is formed by providing bottom side steps 3d, 4d, 10d and 11d so as to pass through meshing step A at the time of suction cutoff after suction cutoff. Thereby, compression can be performed without gas leaking from the compression space S1.

  On the other hand, in Comparative Examples 1 and 2 described below, since the engaging step is provided at a position different from that of the present embodiment, the gas cannot be effectively compressed.

<Comparative Example 1>
If 8 is the bottom side step portion 10d of the third wall 10 'is in the third wall 10 winding end not not provided 10b of proceeds from winding end 10b toward the center at least 90 ° position, That is, this is a case where the meshing step portion A 'is located at a position 90 ° or more toward the center from the suction cutoff position. In such a case, even if the suction cutoff is performed at the winding end 10b of the third wall body 10 as shown in FIG. 8, the engagement step portion A ′ is located beyond the sealable angle range and the sealing is performed. Absent. Specifically, as shown in FIG. 9, in the meshing step portion A ′, the wall-side step portion 3c ′ is located at a position beyond the angle range from the seal start point A1 to the seal end point A2. Gas leaks from the gap G. For this reason, as shown by arrow F1 in FIG. 8, gas leaks from the compression space S1 'through the gap of the meshing step A' and flows into the next room, and the suction suction is completed in the next room. Therefore, gas leaks to the outside as shown by arrow F2.
On the other hand, even at the other meshing step B ′ located in the compression space S1 ′, since the sealing has not been achieved, the other meshing step B ′ communicates with the further inner compression space S2 ′. A leakage flow from the space S2 'to the compression space S1' is formed.
As described above, even when the suction cutoff is performed at the winding end 10b of the third wall body 10 as shown in FIG. 8, a leak flow is generated from the meshing steps A 'and B' to compress the gas. Can not do.
FIG. 10 shows a state where the turning has been further advanced by 90 ° from the state of FIG. As can be seen from the figure, although the seal is achieved at the meshing step B ', the sealing flow has not yet been achieved at the meshing step A', so that a leakage flow occurs.

<Comparative Example 2>
Comparative Example 2 is a case where the meshing step A ″ is located closer to the suction cutoff position than in Comparative Example 1 and is located within 90 ° from the suction cutoff position (end of winding 10b).
In such a case, even if the suction cutoff is performed at the winding end 10b of the third wall body 10 as shown in FIG. 11, the engagement step A "is at a position before reaching the sealable angle range, and the sealing is performed. Specifically, as shown in FIG. 12, at the engagement step A ″, the wall side step is located at a position before reaching the angle range from the seal start point A1 to the seal end point A2. Since the portion 3c "is located, gas leaks from the gap G. Reference numeral 10d" indicates a bottom side step portion. For this reason, as shown by an arrow F4 in FIG. 11, gas leaks from the compression space S1 "through the gap of the meshing step A" and flows into the adjacent room, and the suction suction is completed in the adjacent room. As a result, gas leaks to the outside as shown by arrow F5.
On the other hand, at the other meshing step B ″ located in the compression space S1 ″, sealing is achieved, and no leakage flow occurs at the meshing step B ″.
In this way, even if the suction cutoff is performed at the winding end 10b as shown in FIG. 11, a leak flow is generated from the meshing step A ″, and the gas cannot be compressed. This means that a closed compression space cannot be formed even if the suction is shut off until the step A "is located at the seal start point A1 (see FIG. 12 and the like). Therefore, for example, as in the present embodiment shown in FIG. 3, the engagement step A is positioned so as to engage at the seal start point A1 at the time of suction closing, that is, the bottom side step is placed at the end of winding of the wall. The provision of the meshing step A is an essential condition for forming a closed compression space at the time of suction cutoff.
Note that FIG. 13 shows a state in which the 90 ° turn has further advanced from the state of FIG. As can be seen from the figure, although sealing is achieved at the meshing step B ″, a closed compression space S1 ″ is formed after passing through the meshing step A ″, so that the suction volume increases. Can not be planned.

As described above, according to the scroll compressor of the present embodiment, the following operation and effect can be obtained.
In the two-row scroll meshed with a phase difference of 90 °, bottom side steps 3d, 4d, 10d, 11d are provided at the bottoms corresponding to the winding end positions of the walls 3, 4, 10, 11 for sucking and closing the fluid. When the wall-side step portions 3c, 4c, 10c, and 11c are provided at positions meshing with the bottom-side step portions 3d, 4d, 10d, and 11d, all the compression chambers S1 formed at the time of the suction cutoff are not opened. Compression can be performed while maintaining the compression chamber at the turning angle. As a result, it is possible to achieve three-dimensional compression in which the height of the walls 3, 4, 10, and 11 is added to the double scroll, so that not only the suction volume is increased but also the design volume ratio (design volume ratio) is increased. Pressure ratio) can also be increased.

  In the present embodiment, the number of turns of the wall bodies 3, 4, 10, 11 slightly exceeds (1 + 1/4) turns, but the present invention is not limited to this, and the number of turns is (1 + 1). / 4) It may be shorter or longer than the circumference.

Reference Signs List 1 fixed scroll 2 orbiting scroll 3 first wall 3a winding start 3b winding end 3c wall side step 3d bottom side step 4 second wall 4a winding start 4b winding end 4c wall side step 4d bottom side step 5 Discharge Port 6 end plate (fixed scroll)
7 End plate (orbiting scroll)
10 Third wall body 10a Winding start 10b Winding end 10c Wall side step 10d Bottom step 11 Fourth wall 11a Winding start 11b Winding end 11c Wall side step 11d Bottom side step O1 Spiral center (fixed scroll)
O2 spiral center (scroll scroll)

Claims (1)

A fixed scroll fixed to a fixed position, having a two-walled wall composed of a spiral first wall and a second wall standing on one side of the end plate,
A spiral-shaped third wall and a fourth wall formed on one side surface of the end plate, the third wall being provided for the first wall and the second wall; A revolving scroll supported to be capable of revolving orbiting while being prevented from rotating in a state where the body and the fourth wall are meshed with each other;
With
The first wall body and the second wall body are arranged at a point symmetric position rotated by 180 ° with a common spiral center,
The third wall and the fourth wall are the same shape as the first wall and the second wall, respectively.
The fixed scroll and the orbiting scroll are engaged with each other with a phase difference of 90 °,
In each of the fixed scroll and the orbiting scroll, the bottom on the end plate side corresponding to the winding end position on the outer peripheral side of each of the wall bodies that shuts off by suctioning a fluid has a higher height at the center side than the outer peripheral side. It has a bottom-side step, and has a wall-side step where the tip in the height direction of each of the walls meshing with the bottom-side step is lower on the center side than on the outer peripheral side, so that it is formed at the time of suction cutoff. A scroll compressor that performs compression while maintaining a compression chamber at all orbital angles without opening a compression chamber that has been opened .

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