Abstract
A stationary scroll plate for use in a scroll compressor is described. The stationary scroll plate comprises a base plate having a first side and a second side, wherein the second side opposes the first side; a spiral wrap formed at the first side of the base plate, wherein the spiral wrap is adapted to interact with a corresponding spiral wrap of an orbiting scroll plate to form a compression chamber; an injection channel formed within the base plate, the injection channel providing an injection path for injection of fluid into the compression chamber; a recess located at the second side; an insert placed within the recess, wherein the insert forms a cooling chamber within the recess; an inlet channel via which the cooling chamber is connected to the injection channel; and an outlet channel via which the cooling chamber is connected to the inside of the spiral wrap.
Claims
1. A stationary scroll plate for use in a scroll compressor, the stationary scroll plate comprising: a base plate having a first side and a second side, wherein the second side opposes the first side; a spiral wrap formed at the first side of the base plate, wherein the spiral wrap is adapted to interact with a corresponding spiral wrap of an orbiting scroll plate to form a compression chamber; an injection channel formed within the base plate, the injection channel providing an injection path for injection of fluid into the compression chamber; a recess located at the second side; an insert placed within the recess, wherein the insert forms a cooling chamber within the recess; an inlet channel via which the cooling chamber is connected to the injection channel; and an outlet channel via which the cooling chamber is connected to the inside of the spiral wrap.
2. The stationary scroll plate according to claim 1, wherein the recess located at the second side has an annular shape and wherein the insert placed within the recess forms the cooling chamber in at least a portion of the annular recess.
3. The stationary scroll plate according to any claim 1, wherein the cooling chamber, the inlet channel and the outlet channel define a cooling path configured to guide fluid from the injection channel to the inside of the spiral wrap.
4. The stationary scroll plate according to claim 1, wherein the recess comprises a bottom and two side walls and wherein a sealed contact is established between the insert and both side walls.
5. The stationary scroll plate according to claim 4, wherein the insert comprises at least one protruding element, which contacts the bottom of the recess and thereby defines a height of the cooling chamber.
6. The stationary scroll plate according to claim 4, wherein the insert comprises legs, which establish the sealed connection with the side walls.
7. The stationary scroll plate according to claim 1, wherein the insert is made of steel, cast iron or a non-metal material.
8. A scroll compressor comprising a stationary scroll plate according to claim 1.
9. The scroll compressor according to claim 8, further comprising: an orbiting scroll plate, wherein the orbiting scroll plate comprises: a second base plate having a frontside and a backside, wherein the backside opposes the frontside; and a second spiral wrap formed on the frontside of the base plate; wherein the base plate comprises one or more second recesses and wherein an insulating material is located in at least one of the one or more second recesses of the orbiting scroll plate.
10. The scroll compressor according to claim 9, wherein at least one of the one or more second recesses of the orbiting scroll plate is located at a surface of the backside of the second base plate.
11. The scroll compressor according to claim 9, wherein at least one recess of the one or more second recesses is located beneath the surface of the backside of the base plate.
12. The scroll compressor according to claim 11, wherein the at least one second recess beneath the surface of the backside is formed as a sealed chamber within the second base plate.
13. The scroll compressor according to claim 12, wherein the insulating material located in the at least one second recess beneath the surface of the backside of the second base plate is a fluid.
14. The scroll compressor according to claim 9, wherein the insulating material forms a layer located between the frontside and the backside of the second base plate.
15. The scroll compressor according to claim 9, wherein the insulating material located in the second recess is a non-metal material having a low thermal conductivity.
Description
DRAWINGS
[0040] In the drawings, like reference characters generally refer to the same parts throughout the different drawings. The drawings are not necessarily to scale, emphasis instead generally being placed upon illustrating the principles of the invention.
[0041] In the following description, various embodiments of the invention are described with reference to the following drawings, in which:
[0042] FIG. 1 shows a cross-sectional view of an embodiment of a scroll compressor in which the current invention can be used.
[0043] FIG. 2 shows a highlighted portion of the upper portion of the scroll compressor of FIG. 1 and illustrates the temperature areas within the scroll compressor.
[0044] FIG. 3 shows a cross-sectional view of an embodiment example of a stationary scroll plate with an injection channel.
[0045] FIG. 4a, 4b show cross-sectional views of embodiment examples of stationary scroll plates according to the current invention.
[0046] FIG. 5 shows a partially perspective view of an embodiment example of a stationary scroll plate according to the current invention.
[0047] FIGS. 6a, 6b show two exemplary types of cooling chambers formed within the recess by the insert.
[0048] FIGS. 7a, 7b show (a) a cross-sectional detail view of preferred embodiment of an insert placed within a recess of a stationary scroll plate and (b) a perspective view of the preferred embodiment of the insert.
[0049] FIGS. 8a-8c show cross-sectional views of some embodiments of an orbiting scroll plate that may be used in conjunction with the stationary scroll plate according to the current invention.
[0050] FIGS. 9a-9c show an embodiment example of an orbiting scroll plate of FIG. 8b, wherein (a) is a perspective view of an embodiment example of the orbiting scroll plate cut in half and (b), (c) are top views of the backside of the orbiting scroll plate with different designs of insulating material.
[0051] FIGS. 10a, 10b show another embodiment example of an orbiting scroll plate that may be used in conjunction with the stationary scroll plate according to the current invention, wherein the base plate of the orbiting scroll plate consists of two separate parts, wherein the first part comprises the first side and the second part comprises the second side and wherein the insulating material is placed between the first part and the second part. (a) is a perspective view said embodiment example of the orbiting scroll plate cut in half and (b) is an exploded view of the orbiting scroll plate according to said embodiment.
DETAILED DESCRIPTION
[0052] The following detailed description refers to the accompanying drawings that show, by way of illustration, specific details and embodiments in which the invention may be practiced.
[0053] The word “exemplary” is used herein to mean “serving as an example, instance, or illustration”. Any embodiment or design described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments or designs.
[0054] FIG. 1 shows a cross-sectional view of an embodiment of a scroll compressor in which the current invention can be used. At 100, a scroll compressor is depicted. The scroll compressor comprises a case 110, a suction port 140, a discharge port 150, a stationary scroll plate 120 and an orbiting scroll plate 130. Further, the scroll compressor 100 comprises a motor 160, which is connected to a crankshaft 170 and the crankshaft 170 is connected to the orbiting scroll plate 130. Thereby, the motor drives the crankshaft 170 and causes a rotary motion of the crankshaft 170. Because the crankshaft is connected to the orbiting scroll plate 130, the rotary motion is transferred to an orbiting motion of the orbiting scroll plate 130. Further, the scroll compressor 100 comprises a lubricant supply 180, which may provide lubricant to the crankshaft 170, the orbiting scroll plate 130 and the stationary scroll plate 120.
[0055] The scroll compressor 100 has a low-pressure side and high-pressure side configuration. In this configuration, the low-pressure side comprises a lubricant supply 180, the motor 160, the crankshaft 170 and the suction port 140, whereas the high-pressure side comprises the discharge port 150. The stationary scroll plate 120 and the orbiting scroll plate 130 form a transition area from the low-pressure side to the high-pressure side.
[0056] FIG. 2 shows a highlighted area of the upper portion of the scroll compressor of FIG. 1 and illustrates the temperature areas within the scroll compressor.
[0057] At the low-pressure side, the fluid is received at the suction port. Since the fluid received at the suction port has a rather low pressure and temperature, the temperature at the low-pressure side is also rather low. In FIG. 2, the temperature of the low-pressure side is denoted as suction side temperature T.sub.s. Although the low-pressure side is characterized by a single temperature T.sub.s in FIG. 2, the person skilled in the art will appreciate that the temperature distribution at the low-pressure side is not necessarily homogenous.
[0058] Similarly, at the high-pressure side, the compressed fluid has the highest temperature, which is denoted discharge temperature T.sub.d. Again, the person skilled in the art will appreciate that deviations from the discharge temperature may occur and that the temperature distribution at the high-pressure side is not necessarily homogenous.
[0059] Further, the temperature in the compression chambers formed between the orbiting scroll plate and the stationary plate is higher than or equal to the suction side temperature T.sub.s and lower than or equal to the discharge temperature T.sub.d. During the compression procedure, the temperature in the compression chamber is increased from the suction side temperature T.sub.s to the discharge temperature T.sub.d. The temperature in the compression chambers is denoted T.sub.c. Again, the person skilled in the art will appreciate that the temperature distribution in the compression chambers is not homogenous as has been described before.
[0060] The compressor configuration depicted in FIG. 2 further has a so-called intermediate pressure cavity, which is located between the stationary scroll plate and a portion of the supporting frame to which the stationary scroll plate is attached. The intermediate pressure cavity is connected to the compression chambers for at least a portion of time via a so-called bleed hole, which relates the pressure inside the compression chambers to the pressure inside the intermediate pressure cavity. Further, the intermediate pressure cavity is used for pressing the stationary scroll plate against the orbiting scroll plate, thereby improving the sealing between the scroll plates. As is depicted in FIG. 2, the temperature of the fluid within the intermediate pressure cavity denoted is T.sub.i, which is a temperature higher than the suction side temperature T.sub.s but lower than the discharge temperature T.sub.d.
[0061] As the person skilled in the art will appreciate, the temperature areas depicted in FIG. 2 are simplifications and used for illustrative purposes only. As mentioned earlier, the temperature areas do not need to be homogeneous. Instead, they may represent temperature intervals. This is particularly important for the compression chamber temperature T.sub.c, which ranges from values similar to the suction side temperature T.sub.s at locations on the left and right hand side of FIG. 2 to values similar to the discharge temperature T.sub.d at the center of the interleaved scroll plates.
[0062] The frontside of the stationary scroll plate faces the compression chambers and has a temperature similar to temperature T.sub.c. The backside of the stationary scroll plate is in contact to the intermediate pressure cavity having temperature T.sub.i and in close contact to the high-pressure side having temperature T.sub.d. Therefore, the temperature at the backside of the stationary scroll plate is higher than the temperature T.sub.c of the frontside and may be close to the discharge temperature T.sub.d.
[0063] Similarly, the frontside of the orbiting scroll plate faces the compression chambers and also has a temperature similar to temperature T.sub.c. The backside of the orbiting scroll plate is in contact to the low-pressure side having the suction side temperature T.sub.i. Therefore, the temperature at the backside of the orbiting scroll plate is similar to the suction side temperature T.sub.s.
[0064] FIG. 3 shows a cross-sectional view of a stationary scroll plate 120. The stationary scroll plate comprises a base plate 200 having a first side 205 and a second side 210.
[0065] The first side 205 of the base plate 200 comprises a spiral wrap 270 configured to form one or more compression chambers when being interleaved with a corresponding spiral wrap of an orbiting scroll plate.
[0066] An aperture 220 extends through the base plate and provides a passage from a location within the spiral wrap on the first side to the second side. The passage is indicated in dashed lines and may be used for ejecting compressed fluid from the compression chambers.
[0067] The second side 210 comprises a recess 230. In this example of a stationary scroll plate, the recess 230 is formed as an annular ring around the aperture 220.
[0068] The base plate 220 further comprises an injection channel 280, which provides an injection path for injection of fluid into the compression chamber, which is formed between the corresponding spiral wraps 270. In order to provide for an input into the compression chamber, the first side comprises an opening, the so-called injection hole 290.
[0069] FIGS. 4a and 4b show cross-sectional views of embodiment examples of stationary scroll plates 120a, 120b according to the current invention. Compared to the stationary scroll plate 120, the stationary scroll plate 120a depicted in FIG. 4a comprises an insert 250 placed within the recess 230 on the second side 210 of the base plate 200. The insert 250 forms a cooling chamber 240 within the recess 230, which represents a volume within the recess 230, which is separated from the remaining volume.
[0070] In order to provide a sealed separation from the remaining volume within the recess 230, side portions of the insert 250 are connected to side walls 230a, 230b of the recess 230. The side portions may be formed by legs 255a, 255b as will be illustrated in more detail with respect to FIG. 7a.
[0071] Another portion of the insert 250, which may be formed by a protrusion 260, keeps the insert 250 in a particular distance from the bottom 230c of the recess 230. As is illustrated in FIG. 4, the protrusion 260 may define the height of the cooling chamber 240.
[0072] In the embodiment examples depicted in FIGS. 4a and 4b, the recess 230 and the insert 250 have annular shapes, which will be illustrated in more detail with respect to FIG. 5.
[0073] The fluid that may for example be received from an injection line of a refrigeration cycle flows through the injection channel 280 within the base plate 200. Through an inlet channel 245a, a portion of the fluid flows into the cooling chamber 240. After passing through the cooling chamber 240, the fluid flows through the outlet channel 245b into the compression chamber formed between the interleaved spiral wraps 270.
[0074] FIG. 4b represents another embodiment example of a stationary scroll plate 120b according to the current invention. For illustrative purposes, the aperture 220, which forms the channel for ejecting compressed fluid from the compression chamber, is not shown in FIG. 4b. Compared to the stationary scroll plate 120a, stationary scroll plate 120b has another fluid flow between the cooling chamber 240 and the injection channel 280. In the stationary scroll plate 120b, fluid is again received in the injection channel 280. From there, a portion of the fluid flows through the inlet channel 245a into the cooling chamber 240. After passing through the cooling chamber 240, the fluid flows through the outlet channel 245b back to the injection channel 280 and then through the injection hole 290 into the compression chamber. Compared to the stationary scroll plate 120a, stationary scroll plate 120b reduces the number of openings within the inside of the spiral wrap. Accordingly, the fluid is provided to the compression chambers at less locations, which may make the compression process more uniformly.
[0075] The person skilled in the art will appreciate that there are several other configurations possible. Further, there may be more than one inlet channel 245a and/or more than one outlet channel 245b. In case of two or more outlet channels 245b, it would therefore also be possible to combine the principles depicted in FIGS. 4a and 4b by providing a first outlet channel 245b that directly lead to the inside of the spiral wrap 270, whereas a second outlet channel 245b leads back to the injection channel 280.
[0076] Further, the person skilled in the art will appreciate that there often are two branches of compression chambers are formed between the stationary scroll plate and the orbiting scroll plate. Most commonly, the two branches are formed on either side of the spiral wrap of the orbiting scroll plate when it is orbiting relatively to the spiral wrap of the stationary scroll plate. Preferably, the branches form symmetric compression chambers. For two branches of compression chambers, injection holes 290 and/or outlet channels 245b are provided for each respective one of the two branches.
[0077] FIG. 5 shows a partially perspective view of an embodiment example of a stationary scroll plate 120b according to the current invention. The embodiment example of the stationary scroll plate depicted in FIG. 5 may be similar or identical to the stationary scroll plate 120b depicted in in FIG. 4b. In the view illustrated in FIG. 5, a portion of the stationary scroll plate 120b is cut away in order to illustrate more details of the interior features.
[0078] As can be seen, the recess 230 is an annular recess and extends around the aperture 220. The annular recess 230 and the aperture 220 may be concentric as is depicted in FIG. 5, but this is not necessarily the case.
[0079] The insert 250 placed in the annular recess 230 may also be annular as is illustrated in FIG. 5. In order to achieve a symmetrical distribution of the cooling effect, it is preferred that the insert 250 extends through the entire recess area. However, it is also possible that the insert 250 is only partially annular, so that it extends only through a portion of the recess 230.
[0080] FIGS. 6a and 6b show two exemplary types of cooling chambers formed within the recess by the insert. FIGS. 6a, 6b illustrate a top view of the arrangement of the cooling chamber 240 formed by the insert 250 in the recess 230.
[0081] In the first example, which is depicted in FIG. 6a, the recess 230 has an annular shape and extends around the aperture 220. The cooling chamber 240a formed by the insert 250 within the recess also has an annular shape. The openings of the cooling chamber 240a to inlet and outlet channels, respectively, are not illustrated in the figure but may preferably be located at opposing sides of the annular ring, e.g. at locations corresponding to 12 o'clock and 6 o'clock in the FIG. 6 or any other opposing locations. In this way, the fluid received from the injection channel 280 via the first opening may distribute to two paths within the cooling chamber 240a and be guided to the second opening.
[0082] In the second example, which is depicted in FIG. 6b, the recess 230 again has an annular shape and extends around the aperture 220. The cooling chamber 240b formed by the insert 250 within the recess comprises a path, which is essentially formed by two concentric rings, which are connected. This way, the fluid can enter cooling chamber 240b via the inlet channel that ends in a first opening 310 and is guided through the cooling chamber 240b for almost an entire outer ring of the recess 230, experiences a turn and is then guided within the inner ring towards the second opening 320 from where it is provided outlet channel.
[0083] The person skilled in the art will appreciate that various kinds of other cooling chamber arrangements are also possible and achieve the same or similar effects as the examples, which are explicitly shown in the figures. In particular any arrangement, in which the cooling chamber only covers a portion of the annular recess 230 is also encompassed by the scope of current invention even though such examples are not explicitly shown.
[0084] Further, the person skilled in the art will appreciate that multiple first openings, which connect the cooling chamber with the inlet channel within the base plate, and multiple second openings, which connect the cooling chamber with the outlet channel are also possible, even though this is not explicitly shown. Thereby, curved cooling chambers and several branches can be designed.
[0085] The at least one protrusion of the insert may be used to define the course of the cooling chamber in order to achieve the aforementioned designs.
[0086] FIGS. 7a, 7b show (a) a cross-sectional detail view of preferred embodiment of an insert placed within a recess of a stationary scroll plate and (b) a perspective view of the preferred embodiment of the insert.
[0087] The insert 250 depicted in FIG. 7a essentially has a U-shaped cross-section with two legs 255a and 255b. These legs 255a, 255b can be used to connect the insert 250 to the side walls 230a, 230b of the recess 230. The connection may preferably be a sealed connection, so that the cooling chamber 240 is sealed from the intermediate pressure cavity formed in the remaining part of the recess 230. The sealing may for example be achieved by interference fit or usage of a sealing element.
[0088] Further, the insert 250 comprises at least one protrusion 260. The at least one protrusion 260 lies on the bottom 230c of the recess. Hence, the length of the protrusion 260 defines the height of the cooling chamber 240. In the embodiment example depicted in FIG. 7a, the insert 250 comprises two protrusions 260, which are located at the edges of the insert 250, or in other words at locations opposing the legs 255a, 255b. The two protrusions 260 allow the forming of the cooling chamber 240 between them and the bottom of the recess. Alternatively but not shown, the insert may comprise a single protrusion located centrally (similar to what is shown in FIGS. 4a, 4b), so that the cooling chamber is formed on either sides of the protrusion.
[0089] In another example, which is not depicted in the figures, the legs 255a, 255b of the insert 250 may face toward the bottom 230c of the recess 230. In this case, no protrusion is necessary because the height of the chamber 240 is defined by the length of the legs 255a, 255b.
[0090] Further as is already shown in FIG. 4a, the connection between the insert 250 and the wall of the recess may be sealed by seals 265. These seals may be made of a non-metal material.
[0091] FIG. 7b shows three views of the insert 250 of FIG. 7a without the surrounding stationary scroll plate. The first image is a perspective view of the insert 250, while the second image is a perspective view of a cross-section of the insert 250 and the third image is a cross-sectional view of the insert 250. The insert 250 comprises first and second legs 255a, 255b for being connected to side walls of a recess in a stationary scroll plate and two protrusions 260, which are used for defining the height of the cooling chamber. As can be seen in FIG. 7b, the insert has an annular shape and is configured for being placed in an annular recess in a stationary scroll plate.
[0092] FIGS. 8a to 8c show a cross-sectional views of some embodiments of an orbiting scroll plate, which can be used in conjunction to the stationary scroll plate according to the current invention. In the first embodiment of a scroll plate 130a depicted in FIG. 8a, the scroll plate comprises a second base plate 400 having a first side 405 and a second side 410. The first side comprises a spiral wrap 470 and may also be referred to as frontside. The second side comprises a second recess 420 located at the surface of the second side, which has an annular shape, such that it occurs on the left and right image sides of the surface. A more detailed example of an annular recess will be described below with respect to FIG. 9a. Within the second recess, an insulation material (not shown) can be placed, as will be shown in more detail below with respect to FIGS. 9a to 9c.
[0093] The scroll plate 130a depicted in FIG. 8a is an orbiting scroll plate, as can be identified by the annular protrusion 440, which forms a reception for a crankshaft, as will also be described in more detail below with respect to FIG. 9a.
[0094] Additionally to the features of scroll plate 130a depicted in FIG. 8a, the scroll plate 130b depicted in FIG. 8b comprises an additional second recess 420b, which is located in the reception formed by the annular shaped protrusion 440. The person skilled in the art will appreciate that the second recess 420b can be used additionally to the second recess 420 as is depicted in FIG. 8b or alternatively to recess 420 even though this is not explicitly shown in a separate drawing.
[0095] Whereas the second recesses 420, 420b depicted in FIGS. 8a and 8b are located at the surface of the second side 410 of the second base plate 400, the scroll plate 130c depicted in FIG. 8c comprises second recesses 425, 425b, which are located beneath the surface of the second side 410. Although the second recesses 425, 425b in FIG. 8c are shown at lateral positions (with respect to the surface of the second side of second base plate of the orbiting scroll plate) corresponding to the recesses 420, 420b of the embodiment example depicted in FIG. 8b, the person skilled in the art that other shapes are also possible. For example, a single recess may extend in a plane parallel to the surface of the second base plate 400, may be annular and may have a diameter up to the extend of the second base plate.
[0096] In the embodiment examples of orbiting scroll plates depicted in FIGS. 8a to 8c, the second recesses and the insulating material are placed at the locations near the location of the protrusion for receiving a portion of the crankshaft. Although other locations for the second recess are possible and are encompassed by the scope of the current application, the exemplary locations depicted in the drawings represent preferred examples. In case of a low-pressure side and high-pressure side scroll compressor configuration, these preferred examples account for temperature differences between the first side, which experiences a temperature similar to the discharge temperature in the center of the second spiral wrap 470, and the second side, which experiences the substantially lower side temperature at the annular protrusion 240 caused by lubrication of the crankshaft with a lubricant and additionally contact with vapor at the suction side received from the suction port.
[0097] FIGS. 9a to 9c show embodiment examples of an orbiting scroll plate which can be used in conjunction with the stationary scroll plate according to the current invention, wherein (a) is a perspective view of an embodiment example of an orbiting scroll plate cut in half and (b), (c) are top views of the backside of said orbiting scroll plate. The embodiment example depicted in FIGS. 9a to 9c corresponds to the illustration depicted in FIG. 8b. In these FIGS. 9a to 9c the insulating materials 430 and 460 located in recess 420 and 420b respectively are shown. Further, because of the perspective view, the annular shape of recess 420 and the circular shape of recess 420b as well as the annular shape of the protrusion 440 can be more clearly identified compared to the cross-sectional views depicted in FIG. 8b.
[0098] In FIGS. 9a and 9b, the insulating material 430, 430a is represented by a ring made of insulating material being located in an annular second recess, while the insulating material 460 is represented by a circle or disc made of insulating material located in a circular recess. In contrast to insulating material 430a in FIG. 9b, the insulating material 430b in FIG. 9c does not form a closed ring. This allows the insulating material to increase or decrease its size caused by thermal effects within the insulating material. As the person skilled in the art will appreciate, this benefit may also be achieved by providing multiple portions of insulating material, which are placed in sections of the annular recess.
[0099] FIGS. 10a, 10b show another embodiment example of an orbiting scroll plate 130b which can be used in conjunction with a stationary scroll plate according to the current invention, wherein the second base plate consists of two parts, wherein the first part comprises the first side and the second part comprises the second side and wherein the insulating material is placed between the first part and the second part.
[0100] In this embodiment example, the second base plate of the orbiting scroll plate 130b is formed by a first portion 510, a second portion 520 and an insulating layer 530 placed in a second recess between the first portion 510 and the second portion 520. As such, a second recess in the sense of the current invention may also be interpreted as separation of the base plate into two portions 510 and 520. This embodiment example isolates the first portion 510 from the second portion 520 by ease of the insulating layer 530, which reduces heat transfer between both portions of the base plate of the scroll plate.
[0101] What has been described above includes examples of one or more embodiments. It is, of course, not possible to describe every conceivable combination of components or methodologies for purposes of describing the aforementioned embodiments, but one of ordinary skill in the art may recognize that many further combinations and permutations of various embodiments are possible. Accordingly, the described embodiments are intended to embrace all such alterations, modifications and variations that fall within the scope of the appended claims.
