The present disclosure relates to a compressor, and particularly, to a discharge valve assembly for a compressor.
This section provides background information related to the present disclosure and is not necessarily prior art.
Compressors are used in a variety of industrial, commercial and residential applications to circulate a working fluid within a climate-control system (e.g., a refrigeration system, an air conditioning system, a heat-pump system, a chiller system, etc.) to provide a desired cooling and/or heating effect. A typical climate-control system may include a fluid circuit having an outdoor heat exchanger, an indoor heat exchanger, an expansion device disposed between the indoor and outdoor heat exchangers, and a compressor circulating a working fluid (e.g., refrigerant or carbon dioxide) between the indoor and outdoor heat exchangers. Efficient and reliable operation of the compressor is desirable to ensure that the climate-control system in which the compressor is installed is capable of effectively and efficiently providing a cooling and/or heating effect on demand.
This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features.
The present disclosure provides a compressor that may include a shell, a non-orbiting scroll, an orbiting scroll, a driveshaft, a discharge valve member, and a valve backer. The shell may define a discharge chamber. The non-orbiting scroll may be disposed within the discharge chamber and includes a first end plate and a first spiral wrap extending from the first end plate. The orbiting scroll may be disposed within the discharge chamber and includes a second end plate and a second spiral wrap extending from the second end plate. The first and second spiral wraps mesh with each other to define a plurality of fluid pockets therebetween. The second end plate includes a discharge passage extending therethrough. The driveshaft drives the orbiting scroll and rotates relative to the orbiting scroll. The discharge valve member may be attached to the second end plate and movable between an open position allowing fluid flow from the discharge passage to the discharge chamber and a closed position restricting fluid flow from the discharge passage to the discharge chamber. The valve backer may be disposed on an end of the driveshaft and may be rotatable with the driveshaft relative to the orbiting scroll and the discharge valve member. The valve backer may force the discharge valve member into the closed position during a first portion of a rotation of the driveshaft and may allow the discharge valve member to move into the open position during a second portion of the rotation of the driveshaft.
In some configurations, the valve backer includes an axial end surface having a tip portion and a recessed portion. The tip portion is disposed closer to the second end plate than the recessed portion.
In some configurations, the discharge valve member includes a fixed portion and a movable portion. The movable portion may be deflectable relative to the fixed portion between the open and closed positions.
In some configurations, the tip portion of the valve backer contacts the movable portion and retains the movable portion in contact with a valve seat during the first portion of the rotation of the driveshaft. The recessed portion may be axially aligned with the movable portion during the second portion of the rotation of the driveshaft.
In some configurations, the valve backer includes a recess that at least partially receives an eccentric crank pin of the driveshaft.
In some configurations, the compressor includes a spring disposed within the recess and contacting the valve backer and an axial end of the eccentric crank pin.
In some configurations, the valve backer and the eccentric crank pin are disposed within an annular hub of the orbiting scroll. The annular hub extends from the second end plate in a direction opposite the second spiral wrap.
The fluid pockets defined by the first and second spiral wraps move from a radially outermost position, to a radially intermediate position, to a radially innermost position. In some configurations, the discharge passage receives fluid from the fluid pocket at the radially innermost position.
In some configurations, the valve backer is rotationally fixed relative to the driveshaft.
In some configurations, the valve backer and the driveshaft are separate and discrete components that are attached to each other. In other configurations, the valve backer could be integrally formed with the driveshaft.
The present disclosure also provides a compressor that may include a non-orbiting scroll, an orbiting scroll, a driveshaft, a discharge valve member, and a valve backer. The non-orbiting scroll includes a first end plate and a first spiral wrap extending from the first end plate. The orbiting scroll includes a second end plate and a second spiral wrap extending from the second end plate. The first and second spiral wraps mesh with each other to define a plurality of fluid pockets therebetween. The second end plate includes a discharge passage extending therethrough. The driveshaft drives the orbiting scroll and rotates relative to the orbiting scroll. The discharge valve member may be movable between an open position allowing fluid flow through the discharge passage and a closed position restricting fluid flow through the discharge passage. The valve backer may be movable relative to the discharge valve member and the second end plate to force the discharge valve member into the closed position during a first portion of a rotation of the driveshaft and allow the discharge valve member to move into the open position during a second portion of the rotation of the driveshaft.
In some configurations, the valve backer is rotationally fixed relative to the driveshaft.
In some configurations, the valve backer includes an axial end surface having a tip portion and a recessed portion. The tip portion is disposed closer to the second end plate than the recessed portion.
In some configurations, the discharge valve member includes a fixed portion and a movable portion. The movable portion may be deflectable relative to the fixed portion between the open and closed positions.
In some configurations, the tip portion of the valve backer contacts the movable portion and retains the movable portion in contact with a valve seat during the first portion of the rotation of the driveshaft. The recessed portion may be axially aligned with the movable portion during the second portion of the rotation of the driveshaft.
In some configurations, the valve backer includes a recess that at least partially receives an eccentric crank pin of the driveshaft.
In some configurations, the compressor includes a spring disposed within the recess and contacting the valve backer and an axial end of the eccentric crank pin.
In some configurations, the valve backer and the eccentric crank pin are disposed within an annular hub of the orbiting scroll. The annular hub extends from the second end plate in a direction opposite the second spiral wrap.
The fluid pockets defined by the first and second spiral wraps move from a radially outermost position, to a radially intermediate position, to a radially innermost position. In some configurations, the discharge passage receives fluid from a fluid pocket at the radially innermost position.
In some configurations, the valve backer and the driveshaft are separate and discrete components that are attached to each other. In other configurations, the valve backer could be integrally formed with the driveshaft.
The present disclosure also provides a compressor that may include a non-orbiting scroll, an orbiting scroll, a driveshaft, and a discharge valve member. The non-orbiting scroll includes a first end plate and a first spiral wrap extending from the first end plate. The orbiting scroll includes a second end plate and a second spiral wrap extending from the second end plate. The first and second spiral wraps mesh with each other to define a plurality of fluid pockets therebetween. The second end plate includes a discharge passage that is open to one of the fluid pockets and extends through the second end plate. The driveshaft drives the orbiting scroll. The discharge valve member may be movable between an open position allowing fluid flow from the discharge passage to a discharge chamber and a closed position restricting fluid flow from the discharge passage to the discharge chamber. The discharge valve member may move into the open position in response to a pressure differential between the one of the fluid pockets and the discharge chamber rising above a predetermined value. Movement of the discharge valve member into the closed position may be based on a rotational position of the driveshaft and is independent of the pressure differential between the one of the fluid pockets and the discharge chamber.
In some configurations, the compressor includes a valve backer rotationally fixed relative to the driveshaft and movable relative to the discharge valve member and the second end plate to force the discharge valve member into the closed position during a first portion of a rotation of the driveshaft and allow the discharge valve member to move into the open position during a second portion of the rotation of the driveshaft.
In some configurations, the valve backer includes an axial end surface having a tip portion and a recessed portion.
In some configurations, the tip portion is disposed closer to the second end plate than the recessed portion.
In some configurations, the discharge valve member includes a fixed portion and a movable portion.
In some configurations, the movable portion is deflectable relative to the fixed portion between the open and closed positions.
In some configurations, the tip portion of the valve backer contacts the movable portion and retains the movable portion in contact with a valve seat during the first portion of the rotation of the driveshaft. The recessed portion may be axially aligned with the movable portion during the second portion of the rotation of the driveshaft.
In some configurations, the valve backer and the driveshaft are separate and discrete components that are attached to each other. In other configurations, the valve backer could be integrally formed with the driveshaft.
The fluid pockets defined by the first and second spiral wraps move from a radially outermost position, to a radially intermediate position, to a radially innermost position. In some configurations, the discharge passage receives fluid from the fluid pocket at the radially innermost position.
The present disclosure also provides a compressor that may include a shell, a non-orbiting scroll, an orbiting scroll, and a discharge valve member. The shell may define a discharge chamber. The non-orbiting scroll may be disposed within the discharge chamber and includes a first end plate and a first spiral wrap extending from the first end plate. The orbiting scroll may be disposed within the discharge chamber and includes a second end plate and a second spiral wrap extending from the second end plate. The first and second spiral wraps mesh with each other to define a plurality of fluid pockets therebetween. The second end plate includes a discharge passage extending therethrough. The discharge valve member may be attached to the second end plate and may be movable between an open position allowing fluid flow from the discharge passage to the discharge chamber and a closed position restricting fluid flow from the discharge passage to the discharge chamber.
In some configurations, the discharge valve member moves into the open position in response to a pressure differential between the one of the fluid pockets and the discharge chamber rising above a predetermined value. Movement of the discharge valve member into the closed position may be based on a rotational position of a driveshaft (e.g., a driveshaft driving the orbiting scroll) and may be independent of the pressure differential between the one of the fluid pockets and the discharge chamber.
In some configurations, the compressor includes a valve backer rotationally fixed relative to the driveshaft and movable relative to the discharge valve member and the second end plate to force the discharge valve member into the closed position during a first portion of a rotation of the driveshaft and allow the discharge valve member to move into the open position during a second portion of the rotation of the driveshaft.
In some configurations, the valve backer includes an axial end surface having a tip portion and a recessed portion.
In some configurations, the tip portion is disposed closer to the second end plate than the recessed portion.
In some configurations, the discharge valve member includes a fixed portion and a movable portion.
In some configurations, the movable portion is deflectable relative to the fixed portion between the open and closed positions.
In some configurations, the tip portion of the valve backer contacts the movable portion and retains the movable portion in contact with a valve seat during the first portion of the rotation of the driveshaft.
In some configurations, the recessed portion is axially aligned with the movable portion during the second portion of the rotation of the driveshaft.
The fluid pockets defined by the first and second spiral wraps move from a radially outermost position, to a radially intermediate position, to a radially innermost position. In some configurations, the discharge passage receives fluid from the fluid pocket at the radially innermost position.
In some configurations, the compressor includes a driveshaft driving the orbiting scroll and rotating relative to the orbiting scroll. The discharge valve member may contact the driveshaft in the open position.
In some configurations, the discharge valve member includes a fixed portion and a movable portion. The movable portion is deflectable relative to the fixed portion between the open and closed positions. The movable portion contacts the driveshaft in the open position.
In some configurations, the movable portion contacts an axial end of the driveshaft in the open position.
In some configurations, the movable portion contacts an axial end of an eccentric crank pin of the driveshaft in the open position.
In some configurations, a surface that rotates relative to the orbiting scroll during operation of the compressor contacts the discharge valve member at least intermittently. In some configurations, the surface is an axial end surface of a crank pin of a driveshaft that drives the orbiting scroll. In some configurations, the surface is an axial end surface of a valve backer attached to an end of a driveshaft that drives the orbiting scroll.
Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.
The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.
Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings.
Example embodiments will now be described more fully with reference to the accompanying drawings.
Example embodiments are provided so that this disclosure will be thorough, and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail.
The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms “a,” “an,” and “the” may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprises,” “comprising,” “including,” and “having,” are inclusive and therefore specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed.
When an element or layer is referred to as being “on,” “engaged to,” “connected to,” or “coupled to” another element or layer, it may be directly on, engaged, connected or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly engaged to,” “directly connected to,” or “directly coupled to” another element or layer, there may be no intervening elements or layers present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.). As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.
Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as “first,” “second,” and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.
Spatially relative terms, such as “inner,” “outer,” “beneath,” “below,” “lower,” “above,” “upper,” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. Spatially relative terms may be intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the example term “below” can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.
With reference to
The shell assembly 12 may define a high-pressure discharge chamber 24 (containing compressed working fluid) and may include a cylindrical shell 26, a first end cap 28 at one end thereof, and a base or second end cap 30 at another end thereof. A discharge fitting 32 may be attached to the shell assembly 12 and extend through a first opening in the shell assembly 12 to allow working fluid in the discharge chamber 24 to exit the compressor 10. For example, the discharge fitting 32 may extend through the second end cap 30, as shown in
The first and second bearing assemblies 14, 16 may be disposed entirely within the discharge chamber 24. The first bearing assembly 14 may include a first bearing housing 36 and a first bearing 38. The first bearing housing 36 may be fixed to the shell assembly 12. The first bearing housing 36 houses the first bearing 38 and axially supports the compression mechanism 20. The second bearing assembly 16 may include a second bearing housing 40 and a second bearing 42. The second bearing housing 40 is fixed to the shell assembly 12 and supports the second bearing 42.
The motor assembly 18 may be disposed entirely within the discharge chamber 24 and may include a motor stator 44, a rotor 46, and a driveshaft 48. The stator 44 may be fixedly attached (e.g., by press fit) to the shell 26. The rotor 46 may be press fit on the driveshaft 48 and may transmit rotational power to the driveshaft 48. The driveshaft 48 may include a main body 50 and an eccentric crank pin 52 extending from an axial end of the main body 50. The main body 50 is received in the first and second bearings 38, 42 and is rotatably supported by the first and second bearing assemblies 14, 16. Therefore, the first and second bearings 38, 42 define a rotational axis of the driveshaft 48. The crank pin 52 may engage the compression mechanism 20.
The compression mechanism 20 may be disposed entirely within the discharge chamber 24 and may include an orbiting scroll 54 and a non-orbiting scroll 56. The orbiting scroll 54 may include an end plate 58 having a spiral wrap 60 extending from a first side of the end plate 58. An annular hub 62 may extend from a second side of the end plate 58 and may include a cavity 63 in which a drive bearing 64, a drive bushing 66 and the crank pin 52 may be disposed. The drive bushing 66 may be received within the drive bearing 64. The crank pin 52 may be received within the drive bushing 66.
The end plate 58 of the orbiting scroll 54 may also include a discharge passage 67 that may be open to and disposed directly adjacent to the cavity 63. The discharge passage 67 is in communication with the discharge chamber 24 via the cavity 63. The cavity 63 is in communication with the discharge chamber 24 via gaps between the hub 62 and the drive bearing 64, between the drive bearing 64 and drive bushing 66, and/or between the drive bushing 66 and the crank pin 52. In some configurations, cavity 63 is in communication with the discharge chamber 24 via flow passages formed in any one or more of the hub 62, drive bearing 64, or drive bushing 66, for example.
An Oldham coupling 68 may be engaged with the end plate 58 and either the non-orbiting scroll 56 or the first bearing housing 36 to prevent relative rotation between the orbiting and non-orbiting scrolls 54, 56. The annular hub 62 may be axially supported by a thrust surface 70 of the first bearing housing 36. The annular hub 62 may movably engage a seal 72 attached to the first bearing housing 36 to define an intermediate-pressure cavity 73 between the first bearing housing 36 and the orbiting scroll 54.
The non-orbiting scroll 56 may include an end plate 78 and a spiral wrap 80 projecting from the end plate 78. The spiral wrap 80 may meshingly engage the spiral wrap 60 of the orbiting scroll 54, thereby creating a series of moving fluid pockets therebetween. The fluid pockets defined by the spiral wraps 60, 80 may decrease in volume as they move from a radially outer position 82 to a radially intermediate position 84 to a radially innermost position 86 throughout a compression cycle of the compression mechanism 20. The inlet fitting 34 is fluidly coupled with a suction inlet 77 in the end plate 78 and provides suction-pressure working fluid to the fluid pockets at the radially outer positions 82.
In some configurations, the end plate 78 of the non-orbiting scroll 56 may include a discharge passage 88. The discharge passage 67 in the orbiting scroll 54 and the discharge passage 88 in the non-orbiting scroll 56 may be in communication with the fluid pocket at the radially innermost position 86. The discharge passages 67, 88 are in communication with the discharge chamber 24 and provide compressed working fluid to the discharge chamber 24. In some configurations, the non-orbiting scroll 56 does not have the discharge passage 88. In such configurations, the end plate 58 of the orbiting scroll 54 may include multiple discharge passages 67.
As shown in
The discharge valve member 92 may be a reed valve, for example, and may be a relatively thin and resiliently flexible body having a fixed portion 100 and a movable portion 102. The fixed portion 100 may be fixed relative to the valve seat member 90 and the end plate 58. The movable portion 102 may resiliently deflect relative to the fixed portion 100, the valve seat member 90 and the end plate 58 between an open position (
While the discharge valve member 92 is described above as being a reed valve, in some configurations, the discharge valve member 92 could be another type of valve, such as a linearly movable disk, puck or ball, for example.
The retainer ring 94 may be an annular disk-shaped member and may be fixed to the hub 62 and/or the end plate 58. The retainer ring 94 may contact the valve seat member 90 and/or the fixed portion 100 of the discharge valve member 92 to axially retain the valve seat member 90 and the discharge valve member 92 relative to the end plate 58.
During operation of the compressor 10, fluid pressure within the radially innermost fluid pocket 86 may control movement of the discharge valve member 92 between the open and closed positions. That is, when a pressure differential between the radially innermost fluid pocket 86 and the discharge chamber 24 reaches or rises above a predetermined value, the fluid pressure within the radially innermost fluid pocket 86 may deflect the movable portion 102 of the discharge valve member 92 into the open position. When the pressure differential between the radially innermost fluid pocket 86 and the discharge chamber 24 falls below the predetermined value, the movable portion 102 of the discharge valve member 92 may spring back to the closed position.
As shown in
With reference to
Briefly, the compression mechanism 220 includes an orbiting scroll 254 and a non-orbiting scroll 256. Like the orbiting scroll 54, the orbiting scroll 254 includes an end plate 258, a spiral wrap 260 extending from one side of the end plate 258, and an annular hub 262 extending from the opposite side of the end plate 258. A discharge passage 267 extends through the end plate 258. Like the non-orbiting scroll 56, the non-orbiting scroll 256 includes an end plate 278 (
The discharge valve assembly 222 may include a valve seat member 290, a discharge valve member 292, a retainer ring 294, and a valve backer 296. The valve seat member 290 may be a disk-shaped member having an opening 297 in communication with the discharge passage 267 and the discharge chamber 224 (via cavity 263 defined by the hub 262). The valve seat member 290 may be fixedly attached to the end plate 258 of the orbiting scroll 254. The valve seat member 290 may define a valve seat 298 (
The discharge valve member 292 may be a reed valve, for example, and may be a relatively thin and resiliently flexible body having a fixed portion 300 and a movable portion 302. The fixed portion 300 may be fixed relative to the valve seat member 290 and the end plate 258. The movable portion 302 may resiliently deflect relative to the fixed portion 300, the valve seat member 290 and the end plate 258 between an open position (
While the discharge valve member 292 is described above as being a reed valve, in some configurations, the discharge valve member 292 could be another type of valve, such as a linearly movable disk, puck or ball, for example.
The retainer ring 294 may be an annular disk-shaped member and may be fixed to the hub 262 and/or the end plate 258. The retainer ring 294 may contact the valve seat member 290 and/or the fixed portion 300 of the discharge valve member 292 to axially retain the valve seat member 290 and the discharge valve member 292 relative to the end plate 258.
Pins 291 (
The valve backer 296 may be a generally cylindrical member having a first axial end 304 and a second axial end 306. The first axial end 304 may include a recess 308 in which an eccentric crank pin 252 of the driveshaft 248 is received. The crank pin 252 may include a flat surface 310 (
As shown in
While the valve backer 296 and driveshaft 248 are described above and shown in the figures as being separate and discrete components, in some configurations, the valve backer 296 and driveshaft 248 could be integrally formed. That is, the axial end of the crank pin 252 can be shaped to a tip portion and a recessed portion similar to that of the separate and distinct valve backer 296 described above.
During operation of the compressor 210, the driveshaft 248 and the valve backer 296 rotate together relative to the orbiting scroll 254. During a first portion of each 360-degree-rotation of the driveshaft 248 and valve backer 296, the tip portion 316 of the valve backer 296 is radially spaced apart (i.e., spaced apart in a direction perpendicular to the rotational axis of the driveshaft 248) from the opening 297 in the valve seat member 290 and the movable portion 302 of the discharge valve member 292, and the recessed portion 318 of the valve backer 296 is generally aligned with the opening 297 in the valve seat member 290 and the movable portion 302 of the discharge valve member 292, as shown in
During a second portion of each 360-degree-rotation of the driveshaft 248 and valve backer 296, the tip portion 316 of the valve backer 296 is in contact with the movable portion 302 of the discharge valve member 292, which forces the movable portion 302 into the closed position and restricts or prevents the movable portion 302 from moving toward the open position, as shown in
Closing the discharge valve member 292 using the valve backer 296 in the manner described above reduces noise during operation of the compressor 210 and improves the efficiency of the compressor 210. That is, closing the discharge valve member 292 using the valve backer 296 may reduce the closing velocity of the movable portion 302 of the discharge valve member 292, which reduces the noise generated when the movable portion 302 impacts the valve seat 298. Furthermore, closing the discharge valve member 292 using the valve backer 296 may reduce a delay associated with valve closing. That is, the tip portion 316 and recessed portion 318 of the valve backer 296 can be shaped and positioned such that the discharge valve member 292 is closed at an more optimal time, which can reduce backflow through the discharge passage 267 (i.e., reduce flow of working fluid from the discharge chamber 224 to the radially innermost fluid pocket 286). Reducing backflow improves the efficiency of the compressor 210.
The valve backer 296 allows the opening of the discharge valve member 292 to vary depending on operating conditions (i.e., operating pressure ratio) of the compressor 210 and the climate-control system in which the compressor 210 is installed. However, the closing of the discharge valve member 292 with the valve backer 296 is defined by the geometry of the valve backer 296 and the rotational position of the driveshaft 248, and therefore, is independent of operating conditions of the compressor 210 and the climate-control system in which the compressor 210 is installed. The geometry of the valve backer 296 (i.e., the positioning and shapes of the tip portion 316 and recessed portion 318) can be tailored based on scroll geometry to prevent backflow and to suit a given application.
The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.
This application claims the benefit of U.S. Provisional Application No. 62/455,679, filed on Feb. 7, 2017. The entire disclosure of the above application is incorporated herein by reference.
Number | Date | Country | |
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62455679 | Feb 2017 | US |