The present invention relates to a scroll compressor.
Compressors to compress working fluid such as a refrigerant are used in various apparatuses. Refrigeration cycle apparatuses such as refrigerating machines, water heaters, and air conditioners employ scroll compressors as a device to compress refrigerant gas.
A scroll compressor includes: a fixed scroll including a spiral wrap stood on an end plate (a base plate); and an orbiting scroll including a spiral wrap stood on an end plate (a sliding plate). The scroll compressor has a structure in which the fixed scroll and the orbiting scroll are arranged to face each other so that the wraps thereof engage with each other. In the scroll compressor, the orbiting scroll orbits to sequentially reduce the volumes of a plurality of compression chambers formed between the wraps, thereby compressing the refrigerant.
Such compression operation produces axial force (hereinafter, referred to as “separating force”) which attempts to separate the fixed scroll and the orbiting scroll from each other. In addition to the axial force (separating force), tangential force, radial force, and centrifugal force are applied to the orbiting scroll by the compression operation. These forces produce a moment (an upsetting moment) that attempts to tilt the orbiting scroll. The orbiting scroll thereby swings. If the scrolls are separated from each other, a gap is formed between the end (the end surface) of the wrap and the bottom thereof. Accordingly, the sealing performance of the compression chambers cannot be maintained, and the refrigerant leaks in the compression chambers (especially in the vicinity of the suction chamber where the seal length is short). The efficiency of the compressor is thereby reduced.
In view of this, a backpressure chamber is formed, on the back of the sliding plate of the orbiting scroll, to hold backpressure to press the orbiting scroll against the fixed scroll. The backpressure is pressure within the backpressure chamber and takes an intermediate value between the discharge pressure and the suction pressure. In the scroll compressor having this structure, the orbiting scroll is pressed against the fixed scroll with the backpressure within the backpressure chamber to cancel out the separating force and produce a force (hereinafter, referred to as pressing force) to press a sliding surface of the orbiting scroll against a sliding surface of the fixed scroll. In the scroll compressor having this structure, the refrigerant leakage loss can be reduced in the compression chambers (especially in the vicinity of the suction chamber where the seal length is short) by the pressing force. Herein, the sliding surface of the fixed scroll is a surface formed so as to continue to the end surface of the wrap of the fixed scroll. The sliding surface of the orbiting scroll is a surface of the outer peripheral portion of the sliding plate of the orbiting scroll which comes into contact with the fixed scroll.
However, the pressing force produces sliding friction between the sliding surface of the fixed scroll and the sliding surface of the orbiting scroll. When the pressing force excessively increases, the sliding loss increases, and the performance of the compressor decreases.
Accordingly, a scroll compressor is proposed which includes a backpressure introduced space on the sliding surface of the fixed scroll or the orbiting scroll. To the backpressure introduced space, the pressure (backpressure) within the backpressure chamber is introduced. This increases the pressing force in a region where a lot of refrigerant leaks between the sliding surfaces to reduce the refrigerant leakage loss in the compression chambers (Patent Document 1, for example). In the scroll compressor having this structure, the refrigerant leakage loss in the compression chamber (especially in the vicinity of the suction chamber where the seal length is short) and the sliding loss can be reduced.
Patent Literature 1: Japanese Patent Laid-open Publication No. 2006-152930
However, the conventional scroll compressor described in Patent Literature 1 has a problem that the area of contact between the sliding surface of the fixed scroll and the sliding surface of the orbiting scroll is large, and the sliding loss is still large, as described below.
For example, an object of the conventional scroll compressor described in Patent Literature 1 is to reduce the refrigerant leakage loss between the sliding surface of the fixed scroll and the sliding surface of the orbiting scroll. In the conventional scroll compressor, therefore, the seal length to reduce refrigerant leakage is excessively elongated. The area of contact between the sliding surface of the fixed scroll and the sliding surface of the orbiting scroll is therefore increased, and the sliding loss in the conventional scroll compressor therefore remains large. Such a conventional scroll compressor still has room for improvement.
In addition, as described later, the conventional scroll compressor has a problem that when the backpressure introduced space is expanded, the orbiting scroll is more likely to swing. This can increase the amount of refrigerant leakage in the entire compression chambers.
If the backpressure introduced space is simply expanded in the conventional scroll compressor for the purpose of reducing the area of contact between the sliding surfaces, the force pressing down a portion of the sliding surface of the orbiting scroll that corresponds to the backpressure introduced space increases. Specifically, another force pressing the portion of the sliding surface of the orbiting scroll that corresponds to the backpressure introduced space is produced in addition to the upsetting moment. In the conventional scroll compressor, the orbiting scroll is thus more likely to swing. This can increase the amount of refrigerant leakage in the entire compression chambers.
The present invention has been made to solve the aforementioned problem. A major object of the present invention is to provide a highly-efficient scroll compressor which reduction of the sliding loss is enhanced with a simple structure and reduction of the refrigerant leakage loss in the entire compression chambers is enhanced.
To solve the above problems, the present invention is a scroll compressor including: a fixed scroll including an end plate and a spiral wrap standing on the end plate: an orbiting scroll which includes an end plate and a spiral wrap standing on the end plate and forms a compression chamber between the fixed scroll and the orbiting scroll, the compression chamber having a refrigerant to be compressed therein; a suction section configured to introduce the refrigerant from an outside to an inside of the compressor; a discharge section configured to discharge the refrigerant from the inside to the outside of the compressor; and an electric motor configured to orbit the orbiting scroll. At least one scroll of the fixed scroll and the orbiting scroll includes a sliding surface which is formed outside a wrap with a depression section depressed with respect to the sliding surface and a flange section elevated with respect to the depression section. The flange section is a remaining region in a protruding region disposed outside a referential perfect circle, the remaining region being other than the region continuing to an end of an involute curve of a scroll formed with the flange section, the referential perfect circle having a radius set to a distance between the center of the scroll formed with the flange section and the end of the involute curve.
According to the present invention, it is possible to enhance reducing the sliding loss with a simple structure and enhance reducing the refrigerant leakage loss in the entire compression chamber.
The other means are described later.
Hereinafter, embodiments of the present invention (hereinafter, referred to as embodiments) will be described with reference to the accompanying drawings. Each drawing is just shown schematically to some extent enough to allow sufficient understanding of the present invention. The present invention is not limited to the examples illustrated in the drawings. In each drawing, the same or similar constituent components are given the same reference numerals, and the redundant description thereof is omitted.
Embodiment 1 provides a scroll compressor 1 (see
<Construction of Scroll Compressor>
Hereinafter, the construction of the scroll compressor 1 according to Embodiment 1 will be described with reference to
As illustrated in
The sealed casing 2 includes a cylindrical cylinder chamber 2a, a top chamber 2b, and a bottom chamber 2c and has a sealed structure. The sealed casing 2 is formed by welding the top chamber 2b to the top of the cylinder chamber 2a and welding the bottom chamber 2c to the underside of the cylinder chamber 2a. To the top chamber 2b, a suction pipe 2d is attached. In Embodiment 1, the suction pipe 2d is attached to the upper surface of the top chamber 2b and is positioned so as to extend in the longitudinal direction (that is, positioned lengthwise). To the side surface of the cylinder chamber 2a, a discharge pipe 2e is attached. In the vicinity of the suction pipe 2d within the sealed casing 2, a suction chamber 5c is provided. The suction chamber 5c is a space to which the refrigerant is sucked. The suction chamber 5c serves as a compression chamber 11 after trapping of the refrigerant is completed by the orbital motion of the orbiting scroll 6. Within the sealed casing 2, a discharge pressure space 2f is provided. A discharge port 5e is provided on a center O (see
The compression mechanism 3 includes: the fixed scroll 5 including the spiral wrap 5a on the end plate (base plate) 5b; the orbiting scroll 6 including the spiral wrap 6a on the end plate (sliding plate) 6b; and a frame 9, which is fastened to the fixed scroll 5 with bolts 8 and supports the orbiting scroll 6.
The fixed scroll 5 includes: the end plate (base plate) 5b, which has a circular disk shape; the wrap 5a, which is stood on the base plate 5b in a spiral manner; and a cylindrical support section 5i, which is located on the periphery of the base plate 5b and surrounds the wrap 5a. A bottom surface 5d (see
The fixed scroll 5 is fixed to the frame 9 at the support section 5i with the bolts 8 and the like. The frame 9, which is integrated with the fixed scroll 5, is fixed to the inside of the cylinder chamber 2a of the sealed casing 2 by fixing means such as welding.
On the other hand, the orbiting scroll 6 is disposed within the frame 9 so as to orbit, facing the fixed scroll 5. The orbiting scroll 6 includes: the end plate (the sliding plate) 6b, which has a circular disk shape; the spiral wrap 6a, which is stood on the base plate 6b in the spiral manner; and a boss section 6i, which is provided at the center of the back surface of the sliding plate 6b. The bottom surface 6d (see
On the back of the sliding plate 6b of the orbiting scroll 6, a backpressure chamber 10 is formed. The backpressure chamber 10 holds backpressure to press the orbiting scroll 6 against the fixed scroll 5. The backpressure chamber 10 is formed by the fixed scroll 5, the orbiting scroll 6, a crankshaft 7, and the frame 9. The backpressure chamber 10 is connected to the compression chambers 11 through a communication channel. In the middle of the communication channel, a backpressure regulation valve 10a is provided.
The frame 9 includes a main bearing 9a, which rotatably supports the crankshaft 7. The lower surface side of the orbiting scroll 6 is connected to an eccentric section 7b of the crankshaft 7. The crankshaft 7 is rotatably disposed within the frame 9 and is coaxial with the fixed scroll 5.
Between the lower surface of the orbiting scroll 6 and the frame 9, an Oldham ring 12 is provided. The Oldham ring 12 is a mechanism to restrict the orbiting scroll 6 so that the orbiting scroll 6 does not rotate with respect to the fixed scroll 5 while allowing the orbiting scroll 6 to orbit relatively. The Oldham ring 12 is attached to a groove formed in the lower surface of the orbiting scroll 6 and a groove formed in the upper surface of the frame 9. The Oldham ring 12 allows the orbiting scroll 6 to orbit, without rotating, upon eccentric rotation of the eccentric section 7b of the crankshaft 7.
The electric motor 4 includes a stator 4a and a rotator 4b. The stator 4a is fixed within the sealed casing 2 by pressure insertion, welding, or the like. The rotator 4b is rotatably disposed within the stator 4a. The rotator 4b is fixed to the crankshaft 7.
The crankshaft 7 includes a main shaft 7a and the eccentric section 7b. The crankshaft 7 is supported by the main bearing 9a, which is provided for the frame 9, and a lower bearing 14, which is provided near the bottom of the cylinder chamber 2a. The eccentric section 7b is eccentrically integrated with the main shaft 7a. The eccentric section 7b is fit in an orbiting bearing 6c, which is provided for the boss section 6i in the back of the orbiting scroll 6. The crankshaft 7 is driven by the electric motor 4. In this process, the eccentric section 7b of the crankshaft 7 eccentrically rotates with respect to the main shaft 7a to allow the orbiting scroll 6 to orbit. Within the crankshaft 7, a lubrication channel 7c is provided which introduces the lubricant 13 to the orbiting bearing 6c, main bearing 9a, and lower bearing 14.
As illustrated in
The orbiting scroll 6 is disposed so as to orbit, facing the fixed scroll 5. The compression mechanism 3 causes the orbiting scroll 6 to orbit with the wrap 6a of the orbiting scroll 6 and the wrap 5a of the fixed scroll 5 engaged with each other, thus forming a plurality of crescent compression chambers 11 between the wrap 5a of the fixed scroll 5 and the wrap 6a of the orbiting scroll 6. The plurality of compression chambers 11 communicate with the suction chamber 5c. In Embodiment 1, the plurality of compression chambers 11 include two compression chambers 11 formed on the outer curve and inner curve of the wrap 6a of the orbiting scroll 6. Hereinafter, the compression chamber 11 formed on the outer curve of the wrap 6a of the orbiting scroll 6 is referred to as an outside compression chamber 11a. The compression chamber 11 formed on the inner curve of the wrap 6a of the orbiting scroll 6 is referred to as an inside compression chamber 11b. The outside and inside compression chambers 11a and 11b move toward the discharge port 5e with the orbital motion of the orbiting scroll 6 and continuously decrease in volume with the movement.
When the orbiting scroll 6 orbits with the crankshaft 7 driven by the electric motor 4, the refrigerant is introduced to the compression chambers 11 from the suction pipe 2d through the suction chamber 5c. The compression chambers 11 decreases in volume as the orbiting scroll 6 orbits. The refrigerant is thereby compressed. The compressed refrigerant is discharged from the discharge port 5e to the discharge pressure space 2f within the sealed casing 2 (see
Herein, the operation of the scroll compressor 1 will be described with reference to mainly
First, the scroll compressor 1 drives and rotates the crankshaft 7 with the electric motor 4. The rotational driving force is transmitted from the eccentric section 7b of the crankshaft 7 through the orbiting bearing 6c to the orbiting scroll 6. The orbiting scroll 6 performs orbital motion around the axis (the center O (see
With the orbital motion of the orbiting scroll 6, the compression chambers 11a and 11b (see
In the aforementioned construction, the lubricant 13 is reserved in the bottom of the sealed casing 2. The inside of the sealed casing 2 serves as the discharge pressure space 2f. The pressure (discharge pressure) inside the discharge pressure space 2f is higher than the pressure (backpressure) within the backpressure chamber 10. The lubricant 13 reserved in the bottom of the sealed casing 2 flows into the backpressure chamber 10 through the lubrication channel 7c, which is provided in the crankshaft 7, due to the difference between the discharge pressure within the sealed casing 2 and the backpressure within the backpressure chamber 10. Specifically, the lubricant 13 flows through the lubrication channel 7c, which is provided in the crankshaft 7, and reaches the eccentric section 7b of the crankshaft 7. The lubricant 13 then passes through the orbiting bearing 6c, which is provided in the boss section 6i of the orbiting scroll 6, and the main bearing 9a, which is provided in the frame 9, into the backpressure chamber 10. In this process, the lubricant 13 lubricates the orbiting bearing 6c and main bearing 9a.
The lubricant 13 flows into the backpressure chamber 10 through the orbiting bearing 6c and main bearing 9a with a pressure lower than the discharge pressure since the spaces in the orbiting bearing 6c and main bearing 9a are small. When the backpressure of the backpressure chamber 10 is higher than a specified value, the lubricant 13 having flown into the backpressure chamber 10 opens the backpressure regulation valve 10a, which is provided in the middle of the communication channel connecting the backpressure chamber 10 and compression chambers 11 and flows into the compression chambers 11 to be mixed with the refrigerant. The lubricant 13 having flown into the compression chambers 11 passes through the compression chambers 11 with the refrigerant to be discharged through the discharge port 5e to the discharge pressure space 2f. A part of the lubricant 13 is discharged through the discharge pipe 2e to the refrigeration cycle while the other part is separated from the refrigerant within the sealed casing 2 to return to the bottom of the sealed casing 2.
<Structure to Enhance Reducing Refrigerant Leakage Loss in Compression Chamber and Reducing Sliding Loss>
Herein, the structure to enhance reducing the refrigerant leakage loss in the compression chambers 11 and enhance reducing the sliding loss in the scroll compressor 1 will be described.
In the scroll compressor 1, the operation of the compression mechanism 3 to compress the refrigerant produces axial force (separating force) to separate the fixed scroll 5 from the orbiting scroll 6. Separation of the fixed and orbiting scrolls 5 and 6 forms gaps between the end surface of the wrap 5a and the tooth bottom 5d (see
On the back of the sliding plate 6b of the orbiting scroll 6, the backpressure chamber 10 is formed to hold the backpressure that presses the orbiting scroll 6 against the fixed scroll 5. The backpressure is the pressure within the backpressure chamber 10, and takes an intermediate value between the pressure (discharge pressure) within the discharge pressure space 2f and the pressure (suction pressure) within the suction chamber 5c. In the thus-configured scroll compressor 1, the backpressure of the backpressure chamber 10 presses the orbiting scroll 6 against the fixed scroll 5 to cancel out the separating force and produce a pressing force that presses the sliding surface 6f of the orbiting scroll 6 against the sliding surface 5f of the fixed scroll 5. By the pressing force, the refrigerant leakage loss in the compression chambers 11 (especially in the vicinity of the suction chamber 5c where the seal length is short) is reduced in the scroll compressor 1.
The sliding surfaces 5f and 6f face each other with a minute space interposed therebetween. This space plays a role of separating the backpressure chamber 10 and suction chamber 5c or compression chambers 11. In the fixed scroll 5, this space is filled with the lubricant 13 supplied from the lubrication hole 19 and the lubricant 13 flown into the compression chambers 11, thus securing the sealing performance between the sliding surfaces 5f and 6f and reducing the sliding friction between the sliding surfaces 5f and 6f. The sliding loss is thereby reduced. The smaller the space between the sliding surfaces 5f and 6f, the less the refrigerant leakage at the sliding surfaces 5f and 6f. The magnitude of the space between the sliding surfaces 5f and 6f varies depending on the phase of the orbital motion of the orbiting scroll 6 and the seal length. The amount of refrigerant leakage in the compression chambers 11 therefore varies. The reason therefor will be described later.
When the orbiting scroll 6 orbits, for example, the operation of the compression mechanism 3 to compress the refrigerant produces the axial force (separating force) to separate the fixed scroll and orbiting scroll from each other. By this compression operation, tangential force, radial force, and centrifugal force are applied to the orbiting scroll 6 in addition to the axial force (separating force). These forces produce a moment (upsetting moment) to tilt the orbiting scroll 6, causing the orbiting scroll 6 to swing. The sliding surfaces 5f and 6f of the fixed scroll 5 and the orbiting scroll 6 are not always parallel while the orbiting scroll 6 orbits. Accordingly, the magnitude of the space between the sliding surfaces 5f and 6f changes with the phase of the orbital motion of the orbiting scroll 6. With such a change in the magnitude of the space, the refrigerant leakage in the compression chambers 11 changes.
The refrigerant leakage in the compression chambers 11 is affected by the seal length. Herein, the seal length refers to a length of the sliding surfaces 5f and 6f of the fixed scroll 5 and orbiting scroll 6 in the radial direction and is a length by which the backpressure chamber 10 is separated from the compression chambers 11 or suction chamber 5c.
Herein, the point 5m (see
As illustrated in
The shorter the seal length, the more difficult it is to maintain the sealing performance between the sliding surfaces 5f and 6f, and the more the refrigerant leakage loss. The seal length depends on the location of the seal portion between the sliding surfaces 5f and 6f.
In the scroll compressor 1, as described later, it is difficult to secure sufficient seal length in the vicinity of the suction chamber 5c, and the seal length is the shortest in the vicinity of the suction chamber 5c. In the scroll compressor 1, the amount of refrigerant leakage in the vicinity of the suction chamber 5c is greater than that in the other part of the sliding surface 5f.
In the scroll compressor 1, the difference in pressure between both sides of the seal portion in the vicinity of the suction chamber 5c is the differential pressure between the backpressure and suction pressure. On the other hand, the difference in pressure between the both sides of the other part in the sliding surface 5f is the differential pressure between the backpressure and the pressure within the compression chambers 5e. From the influence of these differential pressures, in the scroll compressor 1, the amount of refrigerant leakage in the vicinity of the suction chamber 11 is greater than that in the other part of the sliding surface 5f.
The scroll compressor 1 therefore includes the depression sections 5g, that function as a backpressure introduced space to which the pressure (backpressure) of the backpressure chamber 10 is introduced, in the sliding surface 5f of the fixed scroll 5 or the sliding surface 6f of the orbiting scroll 6. For example, in the scroll compressor 1, the depression sections 5g are provided in the sliding surface 5f of the fixed scroll 5 as illustrated in
Each depression section 5g is a step provided for the sliding surface 5f of the fixed scroll 5. The depression sections 5g are depressed with respect to the sliding surface 5f. The depression sections 5g function as the backpressure introduced space. In Embodiment 1, each depression section 5g extends from the annular groove 5j to the sliding surface 5f. In the scroll compressor 1, providing the depression sections 5g for the sliding surface 5f of the fixed scroll 5 increases the pressure (backpressure) applied to the depression sections 5g. In the scroll compressor 1, the pressing force is increased in the region between the sliding surfaces 5f and 6f where a larger amount of refrigerant leaks, so that the reduction in refrigerant leakage loss is enhanced.
Meanwhile, there can be a scroll compressor in which the backpressure is simply increased without providing the depression sections 5g in order to press the orbiting scroll 6 against the fixed scroll 5 strongly. However, in the thus-configured scroll compressor, since the backpressure is increased, the amount of the lubricant 13 flown into the suction chamber 5c decreases. This results in an increase in sliding loss between the sliding surfaces 5f and 6f of the fixed scroll 5 and the orbiting scroll 6.
In the scroll compressor 1 according to Embodiment 1, the depression sections 5g are provided for the sliding surface 5f or 6f that can produce a large sliding loss. The area of contact between the sliding surface 5f of the fixed scroll 5 and the sliding surface 6f of the orbiting scroll 6 is thereby reduced, so that the reduction in sliding loss is enhanced.
<Detailed Description of Fixed Scroll Construction>
Hereinafter, the construction of the fixed scroll 5 will be described in detail with reference to
As illustrated in
The annular groove 5j is a step provided on the outer periphery of the sliding surface 5f of the fixed scroll 5 so as to face the backpressure space. The annular groove 5j is depressed with respect to the sliding surface 5f. The annular groove 5j includes a surface different in level from the sliding surface 5f by a predetermined amount. When the orbiting scroll 6 orbits, the end of the sliding surface 6f of the orbiting scroll 6 passes over the annular groove 5j. In this process, the sliding surface 6f of the orbiting scroll 6 is opened to the backpressure space since the annular groove 5j faces the backpressure space. The scroll compressor 1 may be configured so that the annular groove 5j is not provided for the fixed scroll 5.
In the example illustrated in
Each of the depression sections 5g has a shape obtained by expanding a part of the annular groove 5j into the sliding surface 5f. In other words, each depression section 5g is an extension of the width of the annular groove 5j toward the center. The depression sections 5g are formed in a part of the sliding surface 5f other than a later-described region R0 (see
The fixed scroll 5 includes a flange section 5h between the two depression sections 5g. The flange section 5h is a step provided in the outer periphery of the sliding surface 5f of the fixed scroll 5. The flange section 5h is elevated with respect to the depression sections 5g. The surface level of the flange section 5h is equal to or slightly lower than the sliding surface 5f.
Herein, the flange section refers to a remaining region of a protruding region of the sliding surface that are disposed outside of a referential perfect circle, other than the region continuing to the end of the involute curve of the scroll where the flange section is formed. The referential perfect circle has a radius set to the distance between the center of the scroll of interest and the end of the involute curve. When the flange section is provided for the fixed scroll, the involute curve of the scroll is the inside involute curve of the fixed scroll. When the flange section is provided for the orbiting scroll, the involute curve of the scroll is the outside involute curve of the orbiting scroll.
In the example illustrated in
Herein, the perfect circle Lci refers to a circle with a radius set to a distance t between the center O of the fixed scroll 5 and the end point 5m of the inside involute curve Liv of the fixed scroll 5.
The inside involute curve Liv refers to a curve that defines the profile of an inner wall surface 5aa of the wrap 5a of the fixed scroll 5. The inner wall surface 5aa of the wrap 5a of the fixed scroll 5 is formed along the inside involute curve Liv.
The region R0 is a part of the sliding surface 5f and is disposed outside of the perfect circle Lci in the sliding surface 5f of the fixed scroll 5 in order to secure the seal length in the vicinity of the suction chamber 5c.
The region R1 is a part of the sliding surface 5f and is disposed outside of the perfect circle Lci in the sliding surface 5f of the fixed scroll 5 in order to reduce the upsetting moment of the orbiting scroll 6.
In the aforementioned construction, the scroll compressor 1 includes the protruding region R0, which is disposed outside of the perfect circle Lci, in the sliding surface 5f of the fixed scroll 5 in order to secure the seal length in the vicinity of the suction chamber 5c. The scroll compressor 1 also includes the depression sections 5g in the sliding surface 5f of the fixed scroll 5, which is disposed outside of the wrap 5a, in order to reduce the sliding loss during operation. However, the protruding region R0 and depression sections 5g upsets the balance at supporting the orbiting scroll 6, making the orbiting scroll 6 more likely to swing. The scroll compressor 1 according to Embodiment 1 therefore includes the elevated flange section 5h in the sliding surface 5f of the fixed scroll 5 in order to prevent the orbiting scroll 6 from swinging.
In the example illustrated in
The flange section 5h (region R1) is provided so that an area 15a thereof is always smaller than an area 15b of the region R0. The width of the flange section 5h (region R1) is preferably not greater than 20 mm in the light of the magnitude of the region R0 and the magnitude of the depression sections 5g, which function as the backpressure introduced space.
As described above, the lubrication hole 19 for supplying the lubricant 13 is provided in the outer periphery of the fixed scroll 5. The lubrication hole 19 is disposed within the flange section 5h or in the vicinity thereof. The lubrication hole 19 is preferably located downstream of a point P1 in order to supply the lubricant 13 around the flange section 5h that produces frictional resistance between the sliding surface 5f of the fixed scroll 5 and the sliding surface 6f of the orbiting scroll 6. The point P1 is the point where the perfect circle Lci and the flange section 5h (region R1) intersect first. When the fixed scroll 5 includes a plurality of flange sections 5h as illustrated in
At the end of the tooth bottom 5d in the base plate 5b of the fixed scroll 5, the suction chamber 5c is provided. The suction chamber 5c is located in the vicinity of the end point 5m of the inside involute curve Liv of the fixed scroll 5. The end point 5m is located on the edge of the inner circumference of the suction port of the suction chamber 5c. The fixed scroll 5 has a structure in which the radial length of the wrap 5a is short in the vicinity of the suction chamber 5c since the suction chamber 5c is located near the end point 5m. This means that it is difficult to secure sufficient seal length in the vicinity of the suction chamber 5c.
<Operation of Flange Section>
Hereinafter, the operation of the flange section 5h will be described with reference to
As illustrated in
As illustrated in
In the scroll compressor 1 according to Embodiment 1, as illustrated in
In the fixed scroll 5 of the thus-configured scroll compressor 1, the pressing force of the orbiting scroll 6 composed of the backpressure is born at the plurality of places including the flange section 5h and other portions in the sliding surface 5f. Accordingly, even if the force that presses down the sliding surface 6f of the orbiting scroll 6 increases in the portion corresponding to the depression sections 5g, the pressing force from the orbiting scroll 6 composed of the backpressure and the upsetting moment are reduced in the scroll compressor 1, in contrast to the scroll compressor B1 according to the comparative example. Accordingly, in the scroll compressor 1, compared with the scroll compressor B1 according to the comparative example, the orbiting scroll 6 is prevented from swinging while the refrigerant leakage is reduced in the vicinity of the suction chamber 5c where the seal length is short as well as in the entire compression chambers 11.
The above-described operation of the flange section 5h is obtained irrespectively of the phase of the orbital motion of the orbiting scroll 6. In the scroll compressor 1, therefore, the reduction in sliding loss can be enhanced even when the radial width of the seal portion (the region R0, see
As illustrated in
<Modification>
In the construction illustrated in
As illustrated in
Each depression section 6g is a step provided in the sliding surface 6f of the orbiting scroll 6. As illustrated in
The orbiting scroll 6 according to the modification includes the flange section 6h between the two depression sections 6g. The flange section 6h is a step provided in the outer periphery of the sliding surface 6f of the orbiting scroll 6. The flange section 6h is elevated with respect to the depression sections 6g. The surface level of the flange section 6h is equal to or slightly lower than that of the sliding surface 6f.
The flange section 6h is disposed in the sliding surface 6f based on a referential perfect circle with the radius set to the distance between the center of the orbiting scroll 6 in which the flange section 6h is formed and the end of the outside involute curve of the orbiting scroll 6. Specifically, the flange section 6h is provided as a remaining region of the protruding regions disposed outside of the referential perfect circle, other than the region continuing to the end of the outside involute curve.
In the above-described construction, the depression sections 6g function as the backpressure introduced space to introduce the pressure (backpressure) of the backpressure chamber 10 to the sliding surfaces 5f and 6f in the same way as the depression sections 5g (see
Even when the depression sections 6g and flange section 6h are provided in the sliding surface 6f of the orbiting scroll 6 like the modification, the scroll compressor 1 provides the same operation as that in the case where the depression sections 5g and flange section 5h are provided in the sliding surface 5f of the fixed scroll 5 (see
<Major Features of Scroll Compressor>
(1) In the scroll compressor 1, the sliding surface 5f of the fixed scroll 5 is formed outside of the wrap 5a with the depression sections 5g, which are depressed with respect to the sliding surface 5f, and the flange section 5h, which is elevated with respect to the depression sections 5g. Alternatively, the sliding surface 6f of the orbiting scroll 6 is formed outside of the wrap 6a with the depression sections 6g, which are depressed with respect to the sliding surface 6f, and the flange section 6h, which is elevated with respect to the depression sections 6g. The flange section is a remaining region provided in the protruding regions disposed outside of the referential perfect circle, other than the region continuing to the end of the involute curve of the scroll formed withe the flange section. The referential perfect circle has a radius set to a distance between the center of the scroll formed with the flange section and the end of the involute curve of the scroll.
Thus-configured scroll compressor 1 prevents the orbiting scroll 6 from swinging due to the upsetting moment to enhance reducing the sliding loss with the simple structure as well as enhance reducing the refrigerant leakage loss in the entire compression chambers 11.
(2) The area 15a of the flange section 5h, that corresponds to the protruding region R1 among the protruding regions R0 and R1 (see
(3) The lubrication hole 19 (see
(4) The width of the flange section 5h (see
As described above, with the scroll compressor 1 according to Embodiment 1, it is possible to prevent the orbiting scroll 6 from swinging due to the upsetting moment with the simple structure to enhance reducing the sliding loss as well as enhance reducing the refrigerant leakage loss in the entire compression chambers 11.
Hereinafter, the construction of a scroll compressor 1A according to Embodiment 2 will be described with reference to
As illustrated in
In the thus-configured scroll compressor 1A, similarly to the scroll compressor 1 according to Embodiment 1, it is possible to enhance reducing the sliding loss with the simple structure and enhance reducing the refrigerant leakage loss in the entire compression chambers 11.
In the scroll compressor 1A, the lubrication hole 19 is provided within the flange section 5h. The flange section 5h is therefore sufficiently supplied with the lubricant 13. This can reduce the sliding loss of the scroll compressor 1A more than that of the scroll compressor 1 according to Embodiment 1.
Hereinafter, the construction of a scroll compressor 1B according to Embodiment 3 will be described with reference to
As illustrated in
In the thus-configured scroll compressor 1B, similarly to the scroll compressor 1 according to Embodiment 1, it is possible to enhance reducing the sliding loss with the simple structure and enhance reducing the refrigerant leakage loss in the entire compression chambers 11.
In the scroll compressor 1B, additionally, the plurality of flange sections 5h are provided in the sliding surface 5f and are able to bear the pressing force of the orbiting scroll 6 composed of larger backpressure than that in the scroll compressor 1 according to Embodiment 1. The pressing force and upsetting moment can be thereby efficiently reduced in the scroll compressor 1B. In other words, the stability of the orbiting scroll 6 is improved in the scroll compressor 1B. With the scroll compressor 1B, it is possible to prevent the orbiting scroll 6 from swinging and reduce the refrigerant leakage in the vicinity of the suction chamber 5c where the seal length is short as well as reduce the refrigerant leakage in the entire compression chambers 11.
Hereinafter, the construction of a scroll compressor 1C according to Embodiment 4 will be described with reference to
As illustrated in
The surface in the depression sections 5g, which have the non-machining surface, is rougher than the surface of the sliding surface. In the thus-configured scroll compressor 1C, the lubricant efficiently retains in the depression sections 5g. This improves the sealing performance between the sliding surface 5f of the fixed scroll 5 and the sliding surface 6f of the orbiting scroll 6. In addition, the depression sections 5g are partially not machined. This reduces the time and man-hours for the machining process of the scroll compressor 1C and reduces the manufacturing cost thereof.
In the thus-configured scroll compressor 1C, similarly to the scroll compressor 1 according to Embodiment 1, it is possible to enhance reducing the sliding loss with the simple structure and enhance reducing the refrigerant leakage loss in the compression chambers 11.
In the scroll compressor 1C, the sealing performance between the sliding surface 5f of the fixed scroll 5 and the sliding surface 6f of the orbiting scroll 6 can be improved more than that in the scroll compressor 1 according to Embodiment 1. In addition, compared with the scroll compressor 1 according to Embodiment 1, it is possible to significantly reduce the time and man-hours for the machining process of the scroll compressor 1C and reduce the manufacturing cost thereof.
The present invention is not limited to the aforementioned embodiments and includes various modifications. For example, the aforementioned embodiments are described in detail to explain the present invention for easy understanding, and the present invention is not limited to apparatuses including all of the configurations described above. In addition, a part of the configuration of each embodiment can be replaced with the configuration of another embodiment. Alternatively, the configuration of each embodiment can be added to the configuration of another embodiment. Furthermore, a part of the configuration of each embodiment can be subjected to addition, deletion, and replacement of another configuration.
Number | Date | Country | Kind |
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2016-179937 | Sep 2016 | JP | national |
Filing Document | Filing Date | Country | Kind |
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PCT/JP2017/030206 | 8/23/2017 | WO | 00 |