JP2013170540A - Scroll compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a scroll compressor provided with a thrust sliding bearing having high lubricity even in initial operation and a comparatively simple structure to improve the total efficiency of a refrigeration circuit system.SOLUTION: In a scroll compressor, a scroll compression mechanism portion 3 includes an orbiting scroll 34 and a thrust sliding bearing 40 supporting a thrust load from the orbiting scroll 34, and the thrust sliding bearing 40 has a first sliding plate 41 and a second sliding plate 42 having sliding surfaces 41s and 42s respectively which contact and slide each other. The first and second sliding plates 41 and 42 are formed as elastic members having convex sliding surfaces 41s and 42s as a whole, and apply an energizing force in an axis direction opposite to the thrust load to the orbiting scroll 34, and the convex surfaces are transformed so as to become planar when receiving the thrust load.

Description

  The present invention relates to a scroll compressor having a thrust slide bearing.

  As is well known, a scroll compressor has a fixed scroll fixed to a housing and a orbiting scroll that is disposed opposite to the fixed scroll and revolves. The fluid is compressed by the fixed and orbiting scroll. To do. Since the orbiting scroll receives a thrust force based on a pressure difference between the pressure acting on the back surface side thereof and the pressure of the compressed fluid, it is necessary to support this thrust force by a thrust bearing. As a thrust bearing used in a scroll compressor, a sliding bearing is more often used than a rolling bearing because of the ease of dealing with the orbiting scroll's revolving motion. Further, as a lubrication oil supply system for the thrust slide bearing, an oil supply system using a pressure difference generated by the operation of a compressor is often used. In general, thrust sliding bearings are slid between flat surfaces to avoid occurrence of per-portion.

  In the case of the oil supply method using the pressure difference described above, the pressure required for oil supply cannot be obtained in the initial stage of compressor operation, so it is necessary to overcome the problem of rapid wear or seizure of the sliding surface of the thrust bearing during this period There is. In particular, when carbon dioxide is used as the refrigerant, the above-described problem is likely to occur because the thrust load increases.

  In order to prevent the above-described problems from occurring, various structures have been proposed to promote the formation of the oil film by variously contriving the sliding surface of the thrust sliding bearing. For example, a thrust sliding bearing described in Patent Document 1 includes a large number of annular grooves and radial grooves, or a number of island-shaped pressure receiving portions on the sliding surface of the sliding plate.

Japanese Patent Laid-Open No. 2006-316677

  The thrust slide bearing disclosed in Patent Document 1 showed good lubrication performance that promotes the formation of an oil film, but further improved the lubrication performance in the initial stage of operation when the oil supply pressure does not sufficiently increase, and the refrigeration circuit From the aspect of overall system efficiency, it was desired to stabilize the system at an early stage. In addition, the thrust slide bearing disclosed in Patent Document 1 requires a thick space because it is necessary to form a groove in the thrust slide bearing and to have high rigidity that is difficult to deform. .

  The present invention has been made in view of the above problems, and provides a scroll compressor including a thrust slide bearing having a relatively simple configuration having high lubricity even in the initial stage of operation, and improves the overall efficiency of the refrigeration circuit system. With the goal.

  In order to solve the above-mentioned problems, the present invention is a scroll compressor including a scroll compression mechanism (3), wherein the scroll compression mechanism (3) includes a turning scroll (34) and a turning scroll (34). A first sliding plate having a sliding surface (41s, 42s) on which the thrust sliding bearing (40) slides in contact with each other. (41) and a second sliding plate (42), each of the first sliding plate (41) and the second sliding plate (42) is a convex sliding surface (41s, 42s) as a whole. The urging force is applied to the orbiting scroll (34) in the axial direction opposite to the thrust load, but when the thrust load is received, the convex surface is deformed in a direction approaching a flat surface. Scroll pressure To provide a machine.

  As described above, the first and second sliding plates (41, 42) of the thrust bearing (40) are formed as elastic members having both sliding surfaces (41s, 42s) having convex surfaces, and the orbiting scroll ( 34) Since an urging force in the axial direction is applied to the rotating scroll and the fixed scroll, the clearance between the tooth tip and the tooth root of the orbiting scroll and the fixed scroll can be made zero. As a result, the increase in the refrigerant discharge pressure of the compressor after the start is achieved early, the stability of the external refrigerant circuit is accelerated, and the pressure necessary for oil circulation is also established early, so the sliding surface of the thrust bearing The supply of oil to can be accelerated. In addition, the sliding surface of each sliding plate of the thrust bearing forms a convex surface when the compressor is not operating and when rotating at a low speed, so wear powder that may have accumulated between the two sliding surfaces. It becomes possible to discharge foreign matters such as these at an early stage.

  In addition, the code | symbol in the parenthesis attached | subjected to each said means is an example which shows a corresponding relationship with the specific means as described in the Example mentioned later.

It is a longitudinal section showing the whole scroll compressor structure by a 1st embodiment of the present invention. It is a three-plane figure showing the 1st sliding plate which comprises the thrust slide bearing of the scroll compressor of the 1st Embodiment of this invention. It is a typical side view of the thrust slide bearing of the scroll compressor of the 1st Embodiment of this invention. It is a typical side view of the thrust slide bearing of the scroll compressor of the 2nd Embodiment of this invention. It is a typical side view of the thrust slide bearing of the scroll compressor of the 3rd Embodiment of this invention. It is a longitudinal cross-sectional view of the principal part of the scroll compressor of the 4th Embodiment of this invention.

  Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a longitudinal sectional view showing a scroll compressor according to the first embodiment. As shown in this figure, the scroll compressor according to the present embodiment is of a vertical type in which the main shaft is vertically arranged. . Moreover, although the scroll compressor of this embodiment is made so that the carbon dioxide of the refrigerant | coolant used for the heat pump circuit for hot water heaters may be compressed, it is needless to say that it is not limited to such a use and a refrigerant | coolant. In the case of such a carbon dioxide refrigerant, the pressure difference between the high and low is large, and as a result, the thrust load becomes large. Therefore, a great effect by this scroll compressor can be expected.

  First, the overall configuration and operation of the scroll compressor 1 according to the first embodiment will be briefly described. The scroll compressor 1 includes a compression mechanism unit 3 having a main shaft 2 and an electric motor unit that rotationally drives the main shaft 2. 4 and a sealed container 5 for accommodating them, and is connected to a centrifugal oil separator 6.

  The sealed container 5 includes a cylindrical case 5a, and a dish-shaped upper end plate 5b and a lower end plate 5c that close both upper and lower ends of the cylindrical case 5a.

  The electric motor unit 4 includes a stator 13 fixed to the inner peripheral surface of the cylindrical case 5 a and a rotor 14 fixed to the main shaft 2 that is rotationally driven by the electric motor unit 4.

  The compression mechanism unit 3 includes a middle housing 31 fixed at a position adjacent to the stator 13 in the cylindrical case 5a, and a crank mechanism 33 supported by a main bearing 32 that is a radial bearing provided in the middle housing 31. A revolving orbiting scroll 34, a fixed scroll 35 disposed opposite to the revolving scroll 34 and fixed to the cylindrical case 5a, and a thrust sliding bearing (hereinafter referred to as “thrust bearing”) disposed between the orbiting scroll 34 and the middle housing 31. 40).

  The main shaft 2 is vertically supported by the auxiliary bearing 8 fixed to a disk-like support member 7 provided near the upper end plate 5b and the main bearing 32.

  The orbiting scroll 34 is generally formed in a disk shape, and from its lower side, spiral teeth 34a standing in an involute curve downward in FIG. 1, and a boss portion 34b standing in a cylindrical shape on the upper part thereof. Including.

  The fixed scroll 35 is generally formed in a disk shape, is fixed to the cylindrical case 5a, and includes spiral teeth 35a erected in an involute curve shape on the upper side surface thereof.

  The middle housing 31 has a three-stage cylindrical shape that gradually increases in diameter from the motor unit 4 side toward the fixed scroll 35 side, and a small-diameter cylindrical unit 31a close to the motor unit 4 constitutes a main bearing 32. The medium-diameter cylindrical portion 31b adjacent to the small-diameter cylindrical portion 31a accommodates the crank mechanism 33 therein, and the large-diameter cylindrical portion 31c close to the fixed scroll 35 accommodates the orbiting scroll 34 therein. The middle housing 31 is fixed to the inner peripheral surface of the cylindrical case 5a by fixing means such as shrink fitting or welding.

  The crank mechanism 33 is configured by an eccentric shaft portion integrally provided at the lower end portion of the main shaft 2 and a boss portion 34 b of the orbiting scroll 34. The eccentric shaft portion is provided so as to be eccentric by a predetermined amount from the shaft centers of the main bearing 32 and the auxiliary bearing 8.

  An Oldham ring (not shown) for preventing the orbiting scroll 34 from rotating is also disposed between the middle housing 31 and the orbiting scroll 34.

  The thrust bearing 40 in the present embodiment is composed of two donut disk-like sliding plates, which will be described later in detail, and are curved as a whole so as to have a function as a leaf spring. Yes. Further, a thrust load from the orbiting scroll upward in FIG. 1 acts on the thrust bearing 40, and this thrust load is downward in the figure acting on the compression reaction force when compressing the refrigerant and the outside of the orbiting scroll 34. This corresponds to the difference from the axial force based on the pressure of

  The scroll compressor 1 according to the present embodiment is not shown in addition to the oil introduction pipe 9 for introducing the high-pressure oil separated by the oil separator 6, but the compressed refrigerant passes through the oil separator 6. And a discharge pipe for supplying the refrigerant circuit, that is, a heat pump circuit, and a suction pipe for sucking the refrigerant returning from the refrigerant circuit. Although not shown, the discharge pipe and the suction pipe protrude from portions of the cylindrical case 5a that are not shown in FIG.

  The refrigerant flow of the compressor 1 in this embodiment will be briefly described. The refrigerant flows from a suction pipe (not shown) to a suction chamber (not shown) communicating with the outermost peripheral side of the spiral teeth of the fixed scroll 35. Supplied and compressed. The compressed refrigerant is led to a discharge pipe (not shown) from a discharge port 10 provided at the center of the fixed scroll 35, and further led to an oil separator 6 through a pipe line (not shown). There the oil is separated. The refrigerant from which the oil has been separated is sent out from the oil separator 6 to an external refrigerant circuit (not shown), and the pressure decreases while passing through the refrigerant circuit, and returns to the suction pipe (not shown).

  On the other hand, the separated oil is stored in the high-pressure oil storage chamber 6 a below the oil separator 6, and flows into the compressor 1 through the oil introduction pipe 9 from there. By the way, in the compressor 1 of the present embodiment, the oil is moved and circulated using a pressure difference between the pressure in the high-pressure oil storage chamber 6a and the pressure in the relatively low-pressure sealed container 5 as a drive source.

  Oil that has flowed into the compressor 1 is first guided to a space between the lower end of the main shaft 2 and the bottom surface of the boss 34b through a flow path (not shown) formed through the fixed scroll 35 and the orbiting scroll 34. Then, after lubricating the main bearing 32, the crank mechanism 33, and the thrust bearing 40 through a plurality of oil passages (not shown), the oil flows down to the low pressure oil storage chamber 11 provided in the bottom space in the sealed container 5. Further, the oil flowing upward in the oil passage 2 a of the main shaft 2 in FIG. 1 finally flows down into the low-pressure oil storage chamber 11 after lubricating the auxiliary bearing 8.

  The oil stored in the low pressure oil storage chamber 11 is sucked up by the oil supply pipe 12 extending downward from the lower side of the fixed scroll 35, supplied to the sliding surfaces of the orbiting scroll 34 and the fixed scroll 35, and compressed together with the refrigerant. Then, the oil is sent from the discharge pipe (not shown) to the oil separator 6 where it is separated from the refrigerant.

  Next, the thrust bearing 40 of the scroll compressor according to the first embodiment of the present invention will be described in more detail below. The thrust bearing 40 has a disk shape with a diameter of about 90 mm, and has a pair of sliding surfaces that slide in contact with each other, that is, the first sliding plate 41 on the side of the orbiting scroll 34 and the middle housing 31 side. The first sliding plate 41 is non-rotatably attached to the orbiting scroll 34, and the second sliding plate 42 is non-rotatably attached to the middle housing 31. It has been. In the present embodiment, the first sliding plate 41 and the second sliding plate 42 are formed as elastic members having convex sliding surfaces 41 s and 42 s as a whole, and the convex surface is caused by a thrust load received from the orbiting scroll 34. Is made to deform in the direction approaching the plane.

  The first sliding plate 41 and the second sliding plate 42 of the present embodiment are manufactured using high carbon chrome steel or carbon tool steel, are subjected to quenching and tempering treatment, and are further coated with tungsten carbide coating (WCC). Alternatively, a diamond-like carbon (DLC) coating is applied. Each sliding plate has a plate thickness selected from a relatively thin range of 1 to 5 mm.

  Since the first sliding plate 41 and the second sliding plate 42 have the same shape and size, a single figure of them is represented by the first sliding plate 41 and shown in the three views of FIG. As shown in the front view of FIG. 2A, the first sliding plate 41 is formed in a donut disk shape having a central hole 41 a for escaping the boss portion 34 b of the orbiting scroll 34. In addition, the first sliding plate 41 is given a shape deformed in advance so that the sliding surface 41s forms a convex surface as a whole. In the present embodiment, the convex surface of the sliding surface 41s is formed as a cylindrical surface, and is therefore expressed as an arc symmetric with respect to the central axis Ac when viewed in the lower side view of FIG. When viewed from the right side view of FIG. 2C, it is expressed in a straight line.

When the warpage amount C _{1 of the first} sliding plate 41, that is, the plane including the outer peripheral edge of the sliding surface 41 s of the sliding plate is used as the reference plane, the maximum value of the distance from the reference plane to the sliding surface 41 s is: A value in the range of 10 to 100 μm is selected. In FIG. 2B, the warping amount C ₁ is exaggerated for easy understanding of the features.

As shown in FIG. 3, the first sliding plate 41 which is deformed in advance is brought into contact with each other at the central portion of the same second sliding plate 42 and the sliding surfaces 41s and 42s. Are combined so as to be farthest apart. FIG. 3 is a schematic side view of the thrust bearing 40 in a state where the first sliding plate 41 and the second sliding plate 42 are combined, and the left side of the central axis Ac that is a symmetrical axis is drawn. FIG. Maximum value, i.e., the warp amount C ₁ and the sum of the warp amount C ₂ of the second sliding plate 42 of the first sliding plate 41 generating the outer peripheral end of the distance between such sliding surface 41s and 42s The total warpage amount Ct is preferably selected from a value in the range of 20 to 200 μm. The total warpage amount Ct is a value in a free state in which no force is applied to the first sliding plate 41 and the second sliding plate 42.

  In addition, when the thrust bearing 40 is disposed between the orbiting scroll 34 and the middle housing 31, the first sliding plate 41 and the second sliding plate 42 are pre-compressed, that is, the total warpage amount Ct is reduced. Thus, the dimensions of the components of the compressor are set so as to generate an urging force that presses the orbiting scroll 34 downward in the drawing. However, even at this stage, the sliding surfaces 41s and 42s of the sliding plates maintain the convex surfaces.

  By the way, in general, a clearance of about 5 to 20 μm is usually provided between the tooth tip and the tooth bottom of each spiral tooth of the orbiting scroll and the fixed scroll for the purpose of absorbing a dimensional error. Therefore, the orbiting scroll can move freely in the axial direction by the clearance. Also in the compressor 1 of the present embodiment, when it is assumed that each sliding plate of the thrust bearing 40 is completely flat, each part so that the orbiting scroll 34 can freely move at a distance of about 5 to 20 μm in the axial direction. Is dimensioned. The moving distance of the orbiting scroll 34 in the axial direction is hereinafter referred to as “free moving distance”. When the compressor is not operated, the clearance is made zero by the urging force based on the above-described precompression of each sliding plate of the thrust bearing 40. Further, the total warpage amount Ct selected from the value in the range of 20 to 200 μm described above is a value selected from the range of 4 to 20 times the free movement distance of the orbiting scroll 34.

  In the operation stage of the compressor 1 of the present embodiment, the total warpage amount Ct, that is, the clearance between the sliding surfaces, decreases as the engine speed increases and the rotational speed increases. The sliding surfaces 41 s and 42 s are substantially flat and slidable with each other in accordance with the shape of the supporting parts on the back side, that is, the orbiting scroll 34 and the middle housing 31. Move.

  By the way, the first sliding plate 41 is attached to the orbiting scroll 34 so as to prevent relative rotation with the orbiting scroll 34 but to allow the elastic deformation. For this reason, the first sliding plate 41 is formed with a hole having a clearance of about 0.1 to 0.2 mm with respect to the pin for receiving two pins (not shown) extending from the orbiting scroll 34. ing. The second sliding plate 42 has the same structure and is similarly attached to the middle housing 31.

  Thus, the teeth of the scroll teeth 34a and 35a of each scroll are generated by the biasing force generated based on the precompression of the first and second sliding plates 41 and 42 as the elastic members of the thrust bearing 40 in the first embodiment. Since the previous clearance is almost zero, the increase in the refrigerant discharge pressure of the compressor 1 after the start is achieved early, the stability of the refrigerant circuit is accelerated, and the pressure necessary for oil circulation is also established early. Therefore, the oil supply to the sliding surfaces 41s and 42s of the thrust bearing 40 is accelerated. Further, the sliding surfaces 41s and 42s of the respective sliding plates of the thrust bearing 40 form a convex surface when the compressor 1 is not operating and when rotating at a low speed, and therefore, between the two sliding surfaces 41s and 42s. It becomes possible to expel foreign matter such as wear powder that may have accumulated at an early stage. Further, at the time of steady operation in which the thrust load increases, the two sliding surfaces 41 s and 42 s become the shape of the respective support surfaces of the orbiting scroll 34 and the middle housing 31 due to elastic deformation, and change into a substantially flat surface. Can be stably supported on a wide surface.

  According to the scroll compressor of the above-described embodiment, the high-pressure pressure rises early, so that the refrigeration cycle is stabilized in a short time, and the effects of heating and heat absorption are exhibited early, improving the efficiency of the refrigeration circuit system. .

  Next, the scroll compressor 1 according to the second embodiment will be described. The scroll compressor 1 includes a sliding surface 41 s of the first sliding plate 41 and a sliding surface of the second sliding plate 42 of the thrust bearing 40. 42s is different from that of the first embodiment in forming a concave surface together. However, since the other points are the same as in the case of the first embodiment, only the different points will be described below.

  FIG. 4 is a schematic side view of the thrust bearing 40 in a state where the first sliding plate 41 and the second sliding plate 42 of the thrust bearing 40 according to the second embodiment are combined, and the axis of symmetry is It is the figure which drew the left side from a certain central axis line Ac. As shown in this figure, in the second embodiment, the first sliding plate 41 and the second sliding plate 42 are in contact with each other at the outer peripheral ends of the sliding surfaces 41 s and 42 s and are most separated at the center portion. To be combined. The maximum value generated in the central portion of the distance between the sliding surfaces 41s and 42s, that is, the total warpage amount Ct of the first sliding plate 41 and the second sliding plate 42 is the same as that of the first embodiment. As in the case, it is selected from a value in the range of 4 to 20 times the free movement distance of the orbiting scroll.

  In the thrust bearing 40 of the second embodiment, the sliding surfaces 41s and 42s of the two sliding plates are arranged so as to form a concave surface, and the oil is retained in the space formed by the two concave surfaces at the time of starting. Therefore, a sufficient oil film is ensured even at the start. Further, since this thrust bearing 40 is also precompressed at the time of assembly, it is possible to quickly increase the refrigerant discharge pressure of the compressor 1 after starting, to establish the oil supply pressure early, and to As in the case of the first embodiment, the two sliding surfaces 41 s and 42 s change from a concave surface to a flat surface and can stably support a thrust load on a wide surface during operation.

  Next, the scroll compressor 1 according to the third embodiment will be described. In the scroll compressor 1, the first sliding plate 41 of the thrust bearing 40 is formed of a cast material such as a spheroidal graphite cast iron product or a gray cast iron product. Thus, the sliding surface 41s is different from that of the first embodiment in forming a flat surface. However, since the other points are the same as in the case of the first embodiment, only the different points will be described below.

FIG. 5 is a schematic side view of the thrust bearing 40 in a state where the first sliding plate 41 and the second sliding plate 42 of the thrust bearing 40 according to the third embodiment are combined, and the axis of symmetry is the same. It is the figure which drew the left side from a certain central axis line Ac. As shown in this figure, in the third embodiment, the sliding surface 41s of the first sliding plate 41 is a flat surface, and the sliding surface 42s of the second sliding plate 42 forms a convex surface. Therefore, they are combined so that they are in contact with each other at the center of the two sliding surfaces 41 s and 42 s and are most separated at the outer peripheral end. The maximum value generated at the outer peripheral end of the distance between the sliding surfaces, that is, the total warpage amount Ct of the first sliding plate 41 and the second sliding plate 42 is the warpage amount C of the second sliding plate 42 alone. _It is equal to ₂ and is a value selected from a range of 4 to 20 times the free movement distance of the orbiting scroll 34.

  The first sliding plate 41 is thicker than that of the above-described embodiment and has a thickness of 5 mm or more. Further, as shown in Patent Document 1, a large number of annular grooves (not shown) and radial shapes are used. A groove (not shown) or a number of island-shaped pressure receiving parts (not shown) may be formed.

  The thrust bearing 40 in the third embodiment has the same characteristics as those in the first embodiment, and further, the first sliding plate 41 does not need to be an elastic member. It is possible to manufacture the plate 41 from a relatively thick casting material, thereby easily providing a large number of grooves (not shown) or island-shaped pressure receiving parts (not shown) for retaining oil on the sliding surface 41s. Can be formed.

  Further, the first sliding plate of the third embodiment may be manufactured from high carbon chrome steel or carbon tool steel instead of a cast material, and the plate thickness is relatively thin in the range of 1 to 5 mm. It is good.

  By the way, the modified example of the third embodiment in which the relationship between the first sliding plate 41 and the second sliding plate 42 is reversed, that is, the first sliding plate is curved in a convex shape so that the second sliding plate 41 is bent. A modified embodiment that is formed flat is also possible.

  Next, a scroll compressor 1 according to a fourth embodiment will be described below with reference to FIG. This scroll compressor 1 is also of a vertical type in which the main shaft 2 is arranged vertically, and the two sliding surfaces like the thrust bearing 40 in the second embodiment described above form a concave surface together. Although the thrust bearing 40 is provided, the difference from the second embodiment is that the upper surface of the orbiting scroll 34 adjacent to the lower side of the thrust bearing 40, that is, the orbiting scroll 34 to which the first sliding plate 41 is attached is in contact. An oil discharge groove 34c is provided on the upper surface. In the present embodiment, the oil discharge groove 34c is formed from the central portion in contact with the boss portion 34b on the upper surface of the orbiting scroll 34 to the outer peripheral end. Although one groove is represented in FIG. 6, it is needless to say that the number of oil discharge grooves 34 c may be an integer of 1 or more.

  The oil discharge groove 34c acts to discharge excess oil in the thrust bearing 40, and as a result, sliding resistance generated between the sliding surfaces by the excess oil is reduced. Particularly, in the thrust bearing 40 according to the fourth embodiment, the two sliding surfaces form a concave surface so that the oil can be easily retained, but excessive oil may be generated depending on conditions. It is effective to provide the groove 34c.

  In the scroll compressor of the fourth embodiment, the orbiting scroll 34 is disposed below the thrust bearing 40. However, the scroll compressor has the orbiting scroll 34 disposed above the thrust bearing 40 and the middle on the lower side. The housing 31 may be disposed, and in this case, the oil discharge groove is formed in the middle housing 31.

Other Embodiments In each of the above-described embodiments, the convex or concave surfaces of the sliding surfaces 41 s and 42 s are formed as cylindrical surfaces, but column surfaces other than the cylindrical surfaces, for example, elliptical cylindrical surfaces, hyperbolic column surfaces, or May be formed as a parabolic column surface. Further, the entire sliding surface may not be formed of the column surface as described above. For example, the central curved portion is formed of the column surface, and the other portion is a plane smoothly connected to the column surface. It may be formed.

  Furthermore, the convex surface or concave surface of the sliding surface may be formed to include a spherical surface instead of a column surface. In that case, by forming a plurality of slits extending radially from the region adjacent to the central hole of the sliding plate, the spring constant of the sliding plate can be reduced to facilitate elastic deformation.

  Although the scroll compressor 1 of the above-mentioned embodiment was a vertical type, the scroll compressor 1 of the first to third embodiments except the fourth embodiment is a horizontal type in which the main shaft 2 is disposed horizontally. It is also possible to change to

  In the scroll compressor 1 of each of the embodiments described above, the oil is moved and circulated using the discharge pressure of the compressor 1 as a drive source. However, an embodiment in which the oil is moved and circulated by an oil pump is also possible.

2 Spindle 3 Scroll compression mechanism 31 Middle housing 34 Orbiting scroll 35 Fixed scroll 40 Thrust bearing 41 First sliding plate 41s Sliding surface 42 Second sliding plate 42s Sliding surface Ct Total warpage

Claims (15)

A scroll compressor comprising a scroll compression mechanism (3),
The scroll compression mechanism (3) includes a turning scroll (34) and a thrust slide bearing (40) for supporting a thrust load from the turning scroll (34),
The thrust sliding bearing (40) includes a first sliding plate (41) and a second sliding plate (42) each having a sliding surface (41s, 42s) sliding in contact with each other,
Each of the first sliding plate (41) and the second sliding plate (42) is formed as an elastic member having a convex sliding surface (41s, 42s) as a whole, and the orbiting scroll (34). ), An axial biasing force opposite to the thrust load is applied, but the convex surface is deformed in a direction approaching a flat surface when the thrust load is received.   Each of the first sliding plate (41) and the second sliding plate (42) is formed as an elastic member having a sliding surface (41s, 42s) which is a concave surface as a whole instead of a convex surface as a whole, An axial urging force opposite to the thrust load is applied to the orbiting scroll (34), but the concave surface is deformed in a direction approaching a flat surface when the thrust load is received. The scroll compressor according to claim 1. The amount of free movement in the axial direction of the orbiting scroll (34) that is possible when the first sliding plate (41) and the second sliding plate (42) are completely flat is defined,
The maximum value of the distance between the sliding surfaces (41s, 42s) in a free state where no axial force acts on the first sliding plate (41) and the second sliding plate (42), that is, A total warpage amount (Ct) of the two sliding plates (41, 42) is determined,
The total warpage amount (Ct) is a predetermined value within a range of 4 to 20 times the free movement amount in the axial direction of the orbiting scroll (34). Scroll compressor.   The scroll compressor according to claim 3, wherein the first sliding plate (41) and the second sliding plate (42) each have a thickness selected from a range of 1 to 5 mm.   The first sliding plate (41) of the thrust sliding bearing (40) is formed as an inelastic member having a flat sliding surface (41s) that is neither a convex surface nor a concave surface as a whole. The scroll compressor as described in any one of Claims 1-4.   The scroll compressor according to claim 5, wherein the first sliding plate (41) is made of a cast product.   The scroll compressor according to claim 6, wherein the first sliding plate (41) is made of a spheroidal graphite cast iron product or a gray cast iron product.   The scroll compressor according to claim 6 or 7, characterized in that the first sliding plate (41) has a plate thickness of 5 mm or more instead of a plate thickness in the range of 1 to 5 mm.   The heat treatment and the surface treatment are performed on at least one of the first sliding plate (41) and the second sliding plate (42), according to any one of claims 1 to 8. Scroll compressor.   The scroll compressor according to claim 9, wherein the heat treatment is a quenching and tempering treatment, and the surface treatment is a tungsten carbide coating (WCC) or a diamond-like carbon (DLC) coating.   The scroll compressor according to any one of claims 1 to 10, wherein the convex surface or the concave surface of the sliding surface (41s, 42s) includes a column surface. A vertical scroll compressor in which the axis of rotation of the orbiting scroll (34) is arranged vertically;
At least one oil discharge groove in which the scroll compression mechanism (3) is formed on the surface of the constituent member (34) adjacent to the lower side of the thrust slide bearing (40) so as to extend from the inner peripheral side to the outer peripheral side. (34c) It comprises, The scroll compressor as described in any one of Claims 1-11 characterized by the above-mentioned.   The scroll compressor according to any one of claims 1 to 12, wherein lubricating oil is circulated using a discharge pressure generated by the scroll compressor as a drive source.   The scroll compressor according to claim 1, wherein the fluid to be compressed is carbon dioxide.   A water heater system comprising the scroll compressor according to claim 14.

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