This application claims priorities to the Chinese patent applications Nos. 201210535807.6 and 201220682332.9 which are filed on Dec. 12, 2012 with the title of “main bearing housing, movable scroll and scroll compressor” before the Chinese State Intellectual Property Office. The entire disclosures of the applications are incorporated herein by reference.
The application relates to a main bearing housing for a scroll compressor, a movable scroll for a scroll compressor and a scroll compressor.
The descriptions in this section merely provide background information related to the present disclosure, which may not necessarily constitute the prior art.
A scroll compressor generally includes a compression mechanism consisting of a fixed scroll and a movable scroll. The movable scroll is supported by a main bearing housing for proving axial restraint. In an existing scroll compressor, thrust surfaces of the movable scroll and of the main bearing housing are both substantially formed as flat surfaces. However, in certain situations, there cannot be provided a good lubrication for lubricant between such thrust surfaces of the main bearing housing and of the movable scroll with such configuration.
Thus, it is desirable to propose a thrust surface construction where a good lubrication may be available in various situations.
According to an aspect of an embodiment of the present application, a main bearing housing for a compressor is provided, including a thrust surface for supporting a movable scroll. An uneven construction is formed on at least part of the thrust surface such that a hydrodynamic lubrication oil film can be formed from lubricant between the main bearing housing and the movable scroll.
According to another aspect of an embodiment of the present application, a movable scroll for a compressor is provided, including a thrust surface for being supported by a main bearing housing. An uneven construction is formed on at least part of the thrust surface such that lubricant can form a hydrodynamic lubrication oil film between the movable scroll and the main bearing housing.
According to a further aspect of an embodiment of the present application, a compressor is provided, including at least one of the above-mentioned main bearing housing and the above-mentioned movable scroll.
Features and advantages of one or more embodiments of the present application may become apparent from the following description made with reference to the drawings in which:
The following description of various embodiments of the application is only illustrative rather than a limitation to the present application and application or use thereof. Like reference numerals are used to indicate like parts throughout the drawings. Thus, the construction of the like parts will not be descried repeatedly. The dimension relation of various configurations in the drawings a only illustrative, but not representing actual dimension relations.
The general configuration and operation principle of a scroll compressor will be described first with reference to
The movable scroll 160 is supported at one side thereof by the upper portion of the main bearing housing 140 (i.e., the supporting portion), and the drive shaft 130 is supported at one end thereof by a main bearing 144 provided in the main bearing housing 140. An eccentric crankpin 132 is provided on one end of the drive shaft 130, and an unloading bush 142 is provided between the eccentric crankpin 132 and the hub 162 of the movable scroll 160. Under drive of the motor 120, the movable scroll 160 will orbit relative to the fixed scroll 150 (i.e., the central axis of the movable scroll 160 rotates about the central axis of the fixed scroll 150, but the movable scroll 160 itself cannot rotate about its central axis) so as to achieve the compression of fluid. The above orbit motion is achieved by a Oldham coupling 190 provided between the fixed scroll 150 and the movable scroll 160. Fluid compressed by the fixed scroll 150 and the movable scroll 160 is discharged through the discharge port 152 to the high-pressure side. In order to prevent the fluid on the high-pressure side from flowing back to the low-pressure side via the discharge port 152 in certain situations, a check valve or discharge valve 170 may be provided at the discharge port 152.
In order to compress fluid, effective sealing is required between the fixed scroll 150 and the movable scroll 160.
On the one hand, axial sealing is required between the top end of the spiral vane 156 of the fixed scroll 150 and the end plate 164 of the movable scroll 160 and between the top end of the spiral vane 166 of the movable scroll 160 and the end plate 154 of the fixed scroll 150. Generally, a back pressured cavity 158 is provided on the side of the end plate 154 of the fixed scroll 150 opposite to the spiral vane 156. A seal assembly 180 is provided in the back pressured cavity 158, and is limited in the axial displacement by the partition plate 116. The back pressured cavity 158 is in fluid communication with the medium-pressure pocket C2 via a through hole (not shown) formed in the end plate 154 and extending axially so as to create a force for pushing the fixed scroll 150 towards the movable scroll 160. Since the movable scroll 160 is supported on one side thereof by the supporting portion of the main bearing housing 140, the fixed scroll 150 and the movable scroll 160 may be effectively pushed together under the pressure in the back pressured cavity 158. When the pressure in individual compression pockets exceeds a set value, the resultant force from the pressure in these compression pockets will exceed the downward pressure provided in the back pressured cavity 158, so that the fixed scroll 150 will move upwards. Then, the fluid in the compression pockets may leak into the low-pressure side through a gap between the top end of the spiral vane 156 of the fixed scroll 150 and the end plate 164 of the movable scroll 160 and a gap between the top end of the spiral vane 166 of the movable scroll 160 and the end plate 154 of the fixed scroll 150 so as to achieve unloading, thereby providing axial compliance for the scroll compressor.
On the other hand, radial sealing is required between side surfaces of the spiral vane 156 of the fixed scroll 150 and of the spiral vane 166 of the movable scroll 160. Such radial sealing therebetween is generally implemented by means of a centrifugal force generated from the motion of the movable scroll 160 and a drive force provided from the drive shaft 130. Specifically, in operation, under drive of the motor 120, the movable scroll 160 will orbit relative to the fixed scroll 150, so that the movable scroll 160 will generate a centrifugal force. In addition, the eccentric crankpin 132 of the drive shaft 130 may also generate a drive component force during rotation for facilitating the radial sealing between the fixed scroll and the movable scroll. The spiral vane 166 of the movable scroll 160 will abut against the spiral vane 156 of the fixed scroll 150 by means of the centrifugal force and the drive component force mentioned above, thereby achieving the radial sealing therebetween. When incompressible matters (e.g., solid impurities, lubricating oil and liquid lubricate) enter the compression pockets and are jammed between the spiral vane 156 and the spiral vane 166, the spiral vane 156 and the spiral vane 166 can temporarily move away from each other in the radial direction so as to allow the foreign matters to pass therethrough, thereby preventing damage to the spiral vane 156 or 166. Such capability of radial separation from each other provides radial compliance for the scroll compressor, improving the reliability of the compressor.
The process for lubricating various parts of the compressor will be described below. In an example of the vertical scroll compressor shown in
As described above, the axial sealing between the movable scroll 160 and the fixed scroll 150 is mainly achieved by the main bearing housing 140 for axially supporting the movable scroll 160 as well as the seal assembly 180 and the back pressured cavity 158 for providing the fixed scroll 150 with the back pressure. As shown in
In operation of the scroll compressor, the movable scroll 160 may be subject to a drive force from the drive shaft 130, a gas force applied by gas in the compression pockets (including a horizontal component force and a vertical component force), a pressure in the back pressured cavity and a supporting force from the main bearing housing. The movable scroll will tilt with respect to the main bearing under the action of these forces. Thus, as shown in
However, in certain situations, the above tilt orbiting motion of the movable scroll may not be effectively performed, resulting in that the above-mentioned hydrodynamic lubrication oil film of lubricant cannot be formed. For example, with the increasing environmental requirements, there is a trend to use CO2 as the refrigerant of the compressor. In case of using CO2 as refrigerant, on the one hand, since the pressure in the compression pockets is to be increased, the height of the scroll vane will be designed to be lowered in order to enhance the strength of the scroll; on the other hand, since the pressure in the compression pockets is increased, the overall force applied to the movable scroll may be changed such as to reduce the tilt degree of the movable scroll during the orbiting motion.
According to embodiments of the application, even if the movable scroll cannot carry out effective tilt orbiting motion, the hydrodynamic lubrication oil film of lubricant can be formed effectively.
The configuration of the main bearing housing 40 according to a first embodiment of the application will be described below with reference to
As shown in
As shown in the section views of
Each wave W1, W2 and W3 of the corrugated surface may be formed in a wavy-shape, e.g., a sinusoidal shape. Alternatively, as shown in
In the individual wave shapes as shown in
In the example as shown in
The above-mentioned corrugated surface may be produced by any one of the following processes, for example, a) machining, such as turning or grinding; b) pressing; c) stamping. Further, the corrugated surface may be integrally formed on the main bearing housing 40, or the corrugated surface may be formed on a separate member (for example, a stamping part) which is then assembled onto the main bearing housing 40.
The process of forming the hydrodynamic lubrication oil film of lubricant according to the first embodiment of the application will be described below with reference to
In
As described above, the wavelength L of each wave of the corrugated surface may be set to be between 0.25 and 2 times as long as the orbiting gyration radius R of the movable scroll. When the wavelength L is 0.25 times as long as R, a point on the movable scroll may pass over several crests and troughs while orbiting, thereby effectively forming the oil film of lubricant. When the wavelength L is 2 times as long as R, a point on the movable scroll may orbit over a part of a wave. Even so, the gap between any point and the main bearing may be gradually decreased within 50% time duration of orbiting motion, and thus the hydrodynamic oil film may be formed.
In a second embodiment shown in
In the second, third and any other embodiment, each wave of the corrugated surface may be formed in the form of one of the sinusoidal wave, the triangular wave and the trapezoidal wave, and the parameters, such as wavelength L, amplitude h, length of platform Z and the like, of each wave of the corrugated surface may be set as that in the first embodiment. Certainly, the second, third and any other embodiment may bring about the similar advantageous effects as the first embodiment.
A fourth embodiment of the application will be described below with reference to
Similar to the first embodiment, in the fourth embodiment, the uneven construction W may be formed on the entire thrust surface S2 of the movable scroll. The configuration and parameters of the uneven construction W may be chosen with reference to the first to third embodiments. Particularly, the uneven construction W on the thrust surface S2 of the movable scroll 160 may include at least a surface inclined with respect to the thrust surface of the main bearing housing 140. Preferably, the uneven construction W may be shaped as a corrugated surface. The corrugated surface may include one or more waves, and the locus line of the crest or trough of each wave may be configured in one of the following forms: a) the locus line forms a circle with its center being the central axis of the movable scroll; b) the locus line is formed as a spiral line gradually unwound from the radial inside towards the radial outside of the movable scroll; c) the locus line is formed as a line extending radially from the central axis of the movable scroll; d) the locus line is formed as a line perpendicular to the central axis of the movable scroll. Each wave of the corrugated surface may be formed as one of a sinusoidal wave, a triangular wave and a trapezoidal wave. The wavelength of each wave of the corrugated surface is ranged between 0.25 and 2 times, preferably between 0.75 and 1.5 times as long as the orbiting gyration radius of the movable scroll, more preferably, equal to the orbiting gyration radius of the movable scroll. The amplitude of each wave of the corrugated surface may be set to be larger than 10 micrometers, preferably between 30 and 100 micrometers. When each wave of the corrugated surface is a trapezoidal wave, the length of top side of the trapezoidal wave may be between ⅙ and ½ of the wavelength of the trapezoidal wave.
Similarly, the corrugated surface on the movable scroll may be produced by one of the following processes: a) machining, such as turning or grinding; b) pressing; c) stamping. The corrugated surface may be integrally formed on the movable scroll, and the corrugated surface may be formed on a separate member which is then assembled onto the movable scroll.
By using the fourth embodiment alone or in combination with the first embodiment, the same advantageous effects as produced from the first embodiment can be achieved.
According to the application, there may be further provided a scroll compressor including the main bearing housing according to the first, second or fourth embodiment and/or the movable scroll according to the fourth embodiment. The scroll compressor may be a scroll compressor using CO2 as refrigerant. Furthermore, the scroll compressor may be a scroll compressor with a variable frequency operating function.
While various embodiments and variations of the present application have been described in detail above, person skilled in the art will appreciate that the present application is not limited to the specific embodiments and variations described above but may include other possible group or combination.
For example, according to an aspect of the application, a main bearing housing for a scroll compressor is provided, including a thrust surface for supporting a movable scroll, wherein an uneven construction may be formed on at least part of the thrust surface such that a hydrodynamic lubrication oil film may be formed from lubricant between the main bearing housing and the movable scroll.
According to a second aspect of the application, the uneven construction may be formed on the entire thrust surface.
According to a third aspect of the application, the uneven construction may be formed in the form of a corrugated surface.
According to a fourth aspect of the application, the corrugated surface may include one or more waves, each wave has a crest or trough with a locus line in one of the following forms: a) a circle with its center being the central axis of the main bearing housing; b) a spiral line gradually unwound from the radial inside towards the radial outside of the main bearing housing; c) a line extending radially from the central axis of the main bearing housing; and d) a line perpendicular to the central axis of the main bearing housing.
According to a fifth aspect of the application, each wave of the corrugated surface may be one of a sinusoidal wave, a triangular wave and a trapezoidal wave.
According to a sixth aspect of the application, each wave of the corrugated surface may have a wavelength being between 0.25 and 2 times as long as an orbiting gyration radius of the movable scroll.
According to a seventh aspect of the application, each wave of the corrugated surface may have a wavelength being between 0.75 and 1.5 times as long as an orbiting gyration radius of the movable scroll.
According to an eighth aspect of the application, each wave of the corrugated surface may have a wavelength equal to an orbiting gyration radius of the movable scroll.
According to a ninth aspect of the application, each wave of the corrugated surface may have an amplitude larger than 10 micrometers, preferably between 30 and 100 micrometers.
According to a tenth aspect of the application, in case of each wave of the corrugated surface being the trapezoidal wave, a top side of the trapezoidal wave may have a length being ⅙ (a sixth) to ½ (a half) of a wavelength of the trapezoidal wave; and in case of each wave of the corrugated surface being the triangular wave, the triangular wave includes a platform at its vertex angle, and the platform has a length being ⅙ to ½ of a wavelength of the triangular wave.
According to an eleventh aspect of the application, the corrugated surface may be produced in one of the following processes: a) machining, b) pressing, c) stamping.
According to a twelfth aspect of the application, the corrugated surface may be integrally formed on the main bearing housing, or the corrugated surface may be formed on a separate member and then assembled onto the main bearing housing.
According to a thirteenth aspect of the application, the uneven construction on the thrust surface of the main bearing housing may include at least a surface inclined relative to the thrust surface of the movable scroll.
According to a fourteenth aspect of the application, there is provided a movable scroll for a scroll compressor, including a thrust surface for being supported by a main bearing housing, wherein an uneven construction may be formed on at least part of the thrust surface such that a hydrodynamic lubrication oil film may be formed from lubricant between the movable scroll and the main bearing housing.
According to a fifteenth aspect of the application, the uneven construction may be formed on the entire thrust surface.
According to a sixteenth aspect of the application, the uneven construction may be formed in the form of a corrugated surface.
According to a seventeenth aspect of the application, the corrugated surface may include one or more waves, each wave has a crest or trough with a locus line in one of the following forms: a) a circle with its center being the central axis of the movable scroll; b) a spiral line gradually unwound from the radial inside towards the radial outside of the movable scroll; c) a line extending radially from the central axis of the movable scroll; and d) a line perpendicular to the central axis of the movable scroll.
According to an eighteenth aspect of the application, each wave of the corrugated surface may be one of a sinusoidal wave, a triangular wave and a trapezoidal wave.
According to a nineteenth aspect of the application, each wave of the corrugated surface may have a wavelength being between 0.25 and 2 times as long as an orbiting gyration radius of the movable scroll.
According to a twentieth aspect of the application, each wave of the corrugated surface may have a wavelength being between 0.75 and 1.5 times as long as an orbiting gyration radius of the movable scroll.
According to a twenty-first aspect of the application, each wave of the corrugated surface may have a wavelength equal to an orbiting gyration radius of the movable scroll.
According to a twenty-second aspect of the application, each wave of the corrugated surface may have an amplitude larger than 10 micrometers, preferably between 30 and 100 micrometers.
According to a twenty-third aspect of the application, in case of each wave of the corrugated surface being the trapezoidal wave, a top side of the trapezoidal wave may have a length being ⅙ (a sixth) to ½ (a half) of a wavelength of the trapezoidal wave; and in case of each wave of the corrugated surface being the triangular wave, the triangular wave includes a platform at its vertex, and the platform has a length being ⅙ to ½ of a wavelength of the triangular wave.
According to a twenty-fourth aspect of the application, the corrugated surface may be produced in one of the following processes: a) machining, b) pressing, c) stamping.
According to a twenty-fifth aspect of the application, the corrugated surface may be integrally formed on the movable scroll, or the corrugated surface may be formed on a separate member and then assembled onto the movable scroll.
According to a twenty-sixth aspect of the application, the uneven construction on the thrust surface of the main bearing housing may include at least a surface inclined relative to the thrust surface of the main bearing housing.
According to a twenty-seventh aspect of the application, a scroll compressor is provided, including at least one of the above-mentioned main bearing housing and the above-mentioned movable scroll.
According to a twenty-eighth aspect of the application, the scroll compressor may be a scroll compressor using CO2 as working medium.
According to a twenty-ninth aspect of the application, the scroll compressor is a scroll compressor with variable frequency operating function.
While various embodiments of the present application have been described in detail herein, it should be understood that the present application is not limited to the specific embodiments described and illustrated herein in detail, and that those skilled in the art can also make other variations and modifications without departing from the spirit and scope of the application. These variations and modifications should also be deemed to fall into the protective scope of the application. Furthermore, all the elements described herein can be replaced by other technically equivalent elements.
Number | Date | Country | Kind |
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201210535807.6 | Dec 2012 | CN | national |
201220682332.9 | Dec 2012 | CN | national |
Filing Document | Filing Date | Country | Kind |
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PCT/CN2013/086584 | 11/6/2013 | WO | 00 |