JP2006200374A - Rotary compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve volumetric efficiency, by increasing sealability of a second rotary compression element of a rotary compressor. <P>SOLUTION: The rotary compressor 10 is constituted by arranging a second rotary compression element 34 on a motor drive element 14 (drive element) side, and a second rotary compression element 32 on a side opposite to the electric drive element 14. A plurality of lower bolts 80 for assembling the first and second rotary compression elements 32, 34 are inserted from a first cover 68 side of the first rotary compression element 32. Each bolt 80 penetrates the first cover 68, a lower support member 56 as a first support member, an intermediate partition plate 36 as an intermediate partition member, and a second cylinder 38, and the each bolt is screwed in an upper support member 54 as a second support member. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a rotary compressor including a drive element in a hermetic container and first and second rotary compression elements driven by a rotation shaft of the drive element.

  Conventionally, in this type of rotary compressor, for example, a vertical multistage compression rotary compressor having a rotary shaft as a vertical type, a driving element in a hermetic container and first and second driven by the rotating shaft of the driving element The second rotary compression element is arranged on the drive element side (upper side), and the first rotary compression element is arranged on the side opposite to the drive element (lower side).

  The first and second rotary compression elements include upper and lower cylinders that constitute each rotary compression element, each roller that is fitted to each eccentric portion formed on the rotary shaft and rotates eccentrically in each cylinder, and each cylinder An intermediate partition plate that is interposed between the two cylinders and closes the openings of both cylinders, an opening on the side opposite to the driving element of the lower cylinder (lower side), and an opening on the driving element side (upper side) of the upper cylinder And an upper and lower support member having a bearing for the rotating shaft, and an upper and lower cover provided on the outer side of the bearing of each support member to form a discharge silencing chamber between each support member. .

  The first and second rotary compression elements are fixed together by bolts. That is, first, after positioning the upper cover, the upper support member, and the upper cylinder of the second rotary compression element on the drive element side, and fixing them together from above (upper cover side) with bolts, Insert through the rotating shaft. Next, the intermediate partition plate and the lower cylinder of the first rotary compression element are assembled and positioned, inserted into the rotary shaft, and fixed from above with bolts screwed into the lower cylinder. As a result, the lower cylinder of the first rotary compression element is attached to the lower side of the second rotary compression element.

Then, after positioning the lower cover and the support member of the first rotary compression element, the first rotary compression element and the first rotary compression element are inserted by inserting into the rotary shaft, inserting bolts from below the lower cover, and fixing them. The second rotary compression element was integrated (for example, see Patent Document 1)
JP 2003-97473 A

  By the way, in the conventional rotary compressor, the bolt inserted from the lower side of the lower cover is fixed by being screwed into the screw groove formed in the upper cylinder, but in this case, the wall of the upper cylinder is fixed. If the thickness is small, there is a danger that the bolt tightening force will pull the vicinity of the thread groove, the upper cylinder near the bolt will warp toward the intermediate partition plate, and a gap will be created between the upper cylinder and the upper support member above it. There was sex. As a result, the refrigerant leaks between the upper cylinder and the upper support member, and the volume efficiency of the second rotary compression element is reduced.

  The present invention has been made to solve the conventional technical problem, and aims to improve the volume efficiency by improving the sealing performance of the second rotary compression element of the rotary compressor. .

  The rotary compressor of the present invention includes a drive element in a hermetically sealed container, and first and second rotary compression elements driven by a rotation shaft of the drive element. In a rotary compressor in which one rotary compression element is arranged on the side opposite to a drive element, first and second cylinders constituting first and second rotary compression elements, and a first formed on a rotary shaft And first and second rollers that are fitted in the second eccentric portion and eccentrically rotate in the first and second cylinders, and an intermediate partition that is interposed between the cylinders and closes the openings of both cylinders. A first support and a second support that close the member, the opening on the side opposite to the drive element of the first cylinder, and the opening on the drive element side of the second cylinder, and have a bearing for the rotating shaft. Of the member and the first and second support members First and second covers that are provided on the outer side of the receiver and that form discharge muffler chambers between the support members and the first and second rotary compression elements. A plurality of bolts for assembling each of the bolts, and each bolt passes through the first cover, the first support member, the first cylinder, the intermediate partition member, and the second cylinder, and is screwed into the second support member. It is what has been combined.

  According to a second aspect of the present invention, the rotary compressor of the present invention compresses the refrigerant compressed by the first rotary compression element by the second rotary compression element and discharges it into the sealed container, and at least the second rotary compression. Bolts are screwed in the vicinity of the suction passage of the element and at a position substantially opposite to the suction passage with the rotation shaft interposed therebetween.

  According to the rotary compressor of the present invention, the rotary compressor includes a plurality of bolts inserted from the first cover side and for assembling the first and second rotary compression elements, each bolt including the first cover, the first Since the support member, the first cylinder, the intermediate partition member, and the second cylinder pass through and are screwed to the second support member, the second cylinder and the second support member are tightened by the bolt tightening force. It is possible to avoid inconvenience that a gap is generated between the first cylinder and the sealing performance of the second cylinder.

  In particular, when an internal high-pressure type rotary compressor is used that compresses the refrigerant compressed by the first rotary compression element by the second rotary compression element and discharges it into the sealed container as in the invention of claim 2. If the bolt is screwed at least near the suction passage of the second rotary compression element and at a position substantially opposite to the suction passage across the rotation shaft, the suction of the second cylinder and the suction of the second cylinder Because the pressure difference in the vicinity of the passage can avoid the inconvenience of the high-pressure refrigerant in the sealed container flowing into the second cylinder, the volumetric efficiency of the second rotary compression element can be improved.

  Furthermore, for example, by applying each of the above inventions to a rotary compressor using carbon dioxide having a high and low pressure difference as a refrigerant, the performance of the rotary compressor using the carbon dioxide refrigerant can be further improved.

  Hereinafter, an embodiment of a rotary compressor of the present invention will be described in detail with reference to the drawings. FIG. 1 is a longitudinal side view of an internal high-pressure rotary compressor 10 having first and second rotary compression elements 32 and 34 as an embodiment of the rotary compressor of the present invention, and FIG. 2 is a rotary compressor 10 of FIG. Fig. 3 shows longitudinal side views of the first and second rotary compression elements 32 and 34, respectively.

  In each drawing, the rotary compressor 10 of the embodiment is an internal high-pressure type rotary compressor 10 as a drive element disposed in a vertical cylindrical sealed container 12 made of a steel plate above the internal space of the sealed container 12. And the rotary compression mechanism 18 including the first and second rotary compression elements 32 and 34 which are disposed below the electric element 14 and are driven by the rotary shaft 16 of the electric element 14. ing. Note that carbon dioxide is used as a refrigerant in the rotary compressor 10 of the embodiment.

  The sealed container 12 has an oil reservoir at the bottom, a container body 12A that houses the electric element 14 and the rotary compression mechanism 18, and a generally bowl-shaped end cap (lid body) 12B that closes the upper opening of the container body 12A. A circular mounting hole 12D is formed on the upper surface of the end cap 12B, and a terminal (wiring is omitted) 20 for supplying power to the electric element 14 is mounted in the mounting hole 12D. ing.

  The electric element 14 includes a stator 22 that is welded and fixed in an annular shape along the inner peripheral surface of the upper space of the sealed container 12, and a rotor 24 that is inserted and installed inside the stator 22 with a slight gap. The rotor 24 is fixed to a rotary shaft 16 that extends in the vertical direction through the center.

  The stator 22 has a laminated body 26 in which donut-shaped electromagnetic steel plates are laminated, and a stator coil 28 wound around the teeth of the laminated body 26 by a direct winding (concentrated winding) method. Similarly to the stator 22, the rotor 24 is also formed of a laminated body 30 of electromagnetic steel plates.

  The first rotary compression element 32 and the second rotary compression element 34 are electrically connected to the second rotary compression element 34 in the second stage with the intermediate partition plate 36 as an intermediate partition member interposed therebetween. The first rotary compression element 32 which is the first stage on the element 14 side is arranged on the side opposite to the electric element 14. That is, the first rotary compression element 32 and the second rotary compression element 34 are the lower cylinder 40 as the first cylinder and the second cylinder as the first and second rotary compression elements 32, 34. An upper cylinder 38 and an opening on the side of the electric element 14 (upper side) of the lower cylinder 40 interposed between the cylinders 38 and 40 and an opening on the side opposite to the electric element 14 (lower side) of the upper cylinder 38 are provided. The intermediate partition plate 36 to be closed, and the upper and lower cylinders 38, 40 are fitted into first and second eccentric portions 42, 44 provided on the rotary shaft 16 with a phase difference of 180 degrees, and the respective cylinders 38, A first roller 48 and a second roller 46 that rotate eccentrically in the shaft 40, and vanes (not shown) that abut against the rollers 46 and 48 and divide the cylinders 38 and 40 into a low pressure chamber side and a high pressure chamber side, respectively. And lower cylinder 40 A lower support member 56 serving as a first support member having a bearing 56A of the rotating shaft 16 by closing an opening (lower side) opposite to the electric element 14 side, and the electric element 14 side of the second cylinder 38 The upper support member 54 as a second support member having the bearing 54A of the rotating shaft 16 and the bearings 54A and 56A of the upper and lower support members 54 and 56 are provided outside the upper support member 54 while closing the (upper) opening. The first and second covers 63 and 68 are provided between the members 54 and 56 to form the discharge silence chambers 62 and 64, respectively.

  The upper support member 54 and the lower support member 56 are provided with suction passages 58 and 60 that communicate with the inside of the upper and lower cylinders 38 and 40 through suction ports 160 and 161, respectively, and discharge silencing chambers 62 and 64. . The discharge silencing chamber 62 is formed by recessing the surface opposite to the upper cylinder 38 of the upper support member 54 as described above, and closing the recess with the second cover 63. The discharge silencer chamber 64 is formed by recessing the surface of the lower support member 56 opposite to the first cylinder 40 and closing the recess with the first cover 68. That is, the discharge silencing chamber 62 is closed by the second cover 63, and the discharge silencing chamber 64 is closed by the first cover 68.

  In this case, a bearing 54 </ b> A is formed upright at the center of the upper support member 54. A bearing 56 </ b> A is formed through the center of the lower support member 56. The bearing 56A has a substantially donut shape with the rotation shaft 16 as a center and a hole through which the rotation shaft 16 passes in the center. A discharge silencer chamber 64 is provided on the outer periphery of the bearing 56A.

  On the other hand, the first cover 68 is composed of a donut-shaped circular steel plate, and is fixed to the lower support member 56 from below with bolts 80... The lower surface opening of the discharge silencing chamber 64 communicating with the inside of the first cylinder 40 of the compression element 32 is closed. The bolts 80... Are bolts for assembling the first and second rotary compression elements 32 and 34, and their tips are screwed into the upper support member 54. That is, the upper support member 54 is formed with a screw groove that is screwed with a screw thread formed at the tip of the bolt 80.

  Here, a procedure for assembling the rotary compression mechanism unit 18 including the first and second rotary compression elements 32 and 34 will be described. First, the second cover 63, the upper support member 54, and the upper cylinder 38 are positioned, and the two upper bolts 78 and 78 that are screwed into the upper cylinder 38 are axially moved from the second cover 63 side (upper side) ( Insert them in the downward direction. Thereby, the 2nd rotation compression element 34 is assembled.

  Next, the second rotary compression element 34 integrated by the above-described upper bolts 78 and 78 is inserted into the rotary shaft 16 from the upper end side. Next, the intermediate partition plate 36 is assembled with the lower cylinder 40, inserted into the rotary shaft 16 from the lower end side, positioned with the already mounted upper cylinder 38, and screwed into the lower cylinder 40. The upper bolts that are not to be inserted are inserted from the second cover 63 side (upper side) in the axial direction (downward direction) to fix them.

  Then, after the lower support member 56 is inserted into the rotary shaft 16 from the lower end side, the first cover 68 is also inserted from the lower end side into the rotary shaft 16 to close the recessed portion of the lower support member 56 and to Bolts 80... Are inserted from the first cover 68 side (lower side) in the axial direction (upward direction), and the tip end portions are screwed in thread grooves formed in the upper support member 54, respectively. First and second rotary compression elements 32, 34 are assembled. In addition, since the 1st and 2nd eccentric parts 42 and 44 are formed in the rotating shaft 16, it cannot attach to the rotating shaft 16 by methods other than the order mentioned above. Therefore, the first cover 68 is attached to the rotating shaft 16 last.

  In this way, the second rotary compression element 34, the intermediate partition plate 36 and the lower cylinder 40, the lower support member 56, and the first cover 68 are sequentially attached to the rotary shaft 16, and the first cover attached last. The first and second rotary compression elements 32 and 34 are fixed to the rotary shaft 16 by inserting four lower bolts 80... From the lower side of 68 and screwing them into the upper support member 54. Can do.

  By the way, the conventional rotary compressor has a structure in which the lower bolt is screwed by the upper cylinder 38 without being screwed by the upper support member 54 as in the present invention. That is, as shown in FIG. 3, the upper cylinder 38 is formed with a thread groove to be screwed with a screw thread formed at the tip of the lower bolt 80A,... And is fixed by screwing them together. It was. In this case, due to the tightening force of the lower bolt 80A, the vicinity of the thread groove is pulled, and the upper cylinder 38 warps toward the intermediate partition plate 36 (lower side) at the periphery of the bolt 80A. There is a risk that a gap is formed between the upper support members 54 on the upper side. In this case, the sealing performance of the upper cylinder 38 is lowered due to the gap, and there is a problem that refrigerant leaks from there.

  In particular, in the vicinity of the suction passage 58 of the second rotary compression element 34, the high-pressure refrigerant gas in the hermetic container 12 enters the upper cylinder 38 from the gap between the upper cylinder 38 and the upper support member 54, and thus enters the upper cylinder 38. The refrigerant suction amount will decrease. In particular, when carbon dioxide having a large high / low pressure difference is used as a refrigerant as in this embodiment, the pressure in the sealed container 12 (high pressure) and the suction side pressure (intermediate pressure) of the upper cylinder 38 of the second rotary compression element 34 are reduced. Since the pressure difference becomes large, a large amount of refrigerant gas in the sealed container 12 flows into the upper cylinder 38 from the gap, and the amount of refrigerant sucked into the upper cylinder 38 is significantly reduced. As a result, the volumetric efficiency of the second rotary compression element 34 is reduced, which causes a problem that the coefficient of performance COP of the rotary compressor 10 deteriorates.

  However, a screw groove is formed in the upper support member 56 as in the present invention, and the tip of each bolt is screwed together by the upper support member 54, so that there is a gap between the upper cylinder 38 and the upper support member 54. The inconvenience that arises can be avoided in advance. Thereby, the sealing performance of the upper cylinder 38 is improved, and the volume efficiency of the second rotary compression element 34 and the coefficient of performance of the rotary compressor 10 can be improved.

  In the present embodiment, all the four lower bolts 80 are screwed into the upper support member 54. However, the present invention is not limited to this, and at least the second lower bolt 80 is used. The upper support member 54 may be screwed together with the lower bolts 80... Positioned near the suction passage 58 of the rotary compression element 34 and the suction passage 58 across the rotation shaft 16.

  In this way, at least the vicinity of the suction passage 58 of the second rotary compression element 32 and the lower bolt 80... Positioned substantially opposite to the suction passage 58 across the rotation shaft 16 are screwed together by the upper support member 54. As a result, it is possible to avoid the disadvantage that the amount of refrigerant sucked into the upper cylinder 38 from the suction passage 58 is significantly reduced as described above.

  On the other hand, a communication path (not shown) that connects the discharge silencer chamber 62 and the inside of the sealed container 12 is formed in the second cover 63, and a high-temperature and high-pressure compressed by the second rotary compression element 34 from this communication path. Refrigerant gas is discharged into the sealed container 12.

  The sleeves 140 and 141 are disposed on the side surfaces of the container body 12A of the sealed container 12 at positions corresponding to the suction passages 58 and 60 of the upper support member 54 and the lower support member 56, the discharge silencer chamber 64, and the electric element 14. 142 and 143 are fixed by welding. The sleeves 140 and 141 are adjacent to each other in the vertical direction, and the sleeve 142 is substantially diagonal to the sleeve 141.

  One end of a refrigerant introduction pipe 92 for introducing refrigerant gas into the upper cylinder 38 is inserted into and connected to the sleeve 140, and one end of the refrigerant introduction pipe 92 communicates with the suction passage 58 of the upper cylinder 38. This refrigerant introduction pipe 92 passes through the upper side of the sealed container 12 and reaches the sleeve 142, and the other end is inserted and connected into the sleeve 142 and communicates with the discharge silencer chamber 64.

  Further, one end of a refrigerant introduction pipe 94 for introducing refrigerant gas into the lower cylinder 40 is inserted and connected into the sleeve 141, and one end of the refrigerant introduction pipe 94 is communicated with the suction passage 60 of the lower cylinder 40. A refrigerant discharge pipe 96 is inserted and connected into the sleeve 143, and one end of the refrigerant discharge pipe 96 is communicated with the sealed container 12.

  Next, the operation of the rotary compressor 10 with the above configuration will be described. When the stator coil 28 of the electric element 14 is energized through the terminal 20 and a wiring (not shown), the electric element 14 is activated and the rotor 24 rotates. By this rotation, the first and second rollers 46 and 48 fitted to the first and second eccentric portions 42 and 44 provided integrally with the rotating shaft 16 eccentrically rotate in the upper and lower cylinders 38 and 40.

  Thus, the low pressure (first stage suction pressure is about 4 MPaG) sucked from the suction port 161 to the lower cylinder 40 through the refrigerant introduction pipe 94 and the suction passage 60 formed in the lower support member 56 to the low pressure chamber side. The refrigerant gas is compressed to an intermediate pressure by the operation of the first roller 48 and a vane (not shown). The refrigerant gas having the intermediate pressure is discharged from the high pressure chamber side of the lower cylinder 40 into a discharge silencer chamber 64 formed in the lower support member 56 via a discharge port (not shown).

  The intermediate-pressure refrigerant gas discharged into the discharge silencer chamber 64 passes through the refrigerant introduction pipe 92 communicated with the discharge silencer chamber 64 and passes through the suction passage 58 formed in the upper support member 54. The air is sucked into the low pressure chamber side of the upper cylinder 38 from the suction port 160.

  The sucked intermediate-pressure refrigerant gas is compressed at the second stage by the operation of the roller 46 and a vane (not shown) to become a high-temperature and high-pressure refrigerant gas (about 12 MPaG). Then, high-temperature and high-pressure refrigerant gas is discharged from the high-pressure chamber side of the upper cylinder 38 to the discharge silencer chamber 62 formed in the upper support member 54 via the discharge port.

  Then, the refrigerant discharged into the discharge silencer chamber 62 is discharged into the sealed container 12 via a communication path (not shown), then passes through the gap of the electric element 14 and moves upward in the sealed container 12, The refrigerant is discharged from the refrigerant discharge pipe 96 connected to the upper side of the sealed container 12 to the outside of the rotary compressor 10.

  As described above in detail, a thread groove is formed in the upper support member 56 as in the present invention, and the tip of each lower bolt 80... Is screwed with the upper support member 54, so that the lower bolt 80. The inconvenience that a gap is generated between the upper cylinder 38 and the upper support member 54 due to the tightening force can be avoided.

  That is, a gap is formed between the upper cylinder 38 and the upper support member 54 and the upper cylinder 38 in the vicinity fixed by the lower bolt 80... 36, which causes a gap between the upper cylinder 38 and the upper support member 54, from which the leakage of the refrigerant gas into which the high-pressure refrigerant gas in the sealed container 12 flows can be eliminated. The sealing performance of the cylinder 38 can be improved.

  Thereby, the volumetric efficiency of the second rotary compression element 34 is improved, and the coefficient of performance of the rotary compressor 10 is also improved, so that the performance of the rotary compressor 10 can be improved.

  In this embodiment, the internal high-pressure type rotary compressor 10 including the first and second rotary compression elements 32 and 34 has been described as the rotary compressor. However, the present invention is not limited to this, and three or more stages are used. The present invention may be applied to a rotary compressor having a rotary compression element. In addition to the internal high-pressure type rotary compressor 10, an internal intermediate pressure type in which the refrigerant compressed by the first rotary compression element is discharged into the sealed container and then compressed by the second rotary compression element, or sealed The present invention may be applied to an internal low-pressure rotary compressor that does not discharge refrigerant into the container.

  In the embodiment, the second rotation compression element 34 provided on the electric element 14 side is the second stage, and the first rotation compression element 32 opposite to the electric element 14 is the first stage, and the first rotation The refrigerant compressed by the compression element 32 is compressed by the second rotary compression element 34, but not limited to this, the second rotary compression element is the first stage, and the first rotary compression element is the second stage. As described above, the refrigerant compressed by the second rotary compression element may be compressed by the first rotary compression element.

  Furthermore, in the present embodiment, the rotary shaft is described as being a vertical type, but it goes without saying that the present invention can also be applied to a rotary compressor having a rotary shaft as a horizontal type. Further, although carbon dioxide is used as the refrigerant of the rotary compressor, other refrigerants may be used.

It is a vertical side view of the rotary compressor of one Example of this invention. It is a vertical side view of the 1st and 2nd rotary compression element of the rotary compressor of FIG. It is a vertical side view of the 1st and 2nd rotary compression element of the conventional rotary compressor.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Rotary compressor 12 Airtight container 14 Electric element 16 Rotating shaft 18 Rotation compression mechanism part 20 Terminal 22 Stator 24 Rotor 26 Laminated body 28 Stator coil 30 Laminated body 32 1st rotation compression element 34 2nd rotation compression element 38 Upper cylinder 40 Lower cylinder 42 Second eccentric portion 44 First eccentric portion 46 Second roller 48 First roller 54 Upper support member 56 Lower support member 54A, 56A Bearings 62, 64 Discharge silencer chamber 63 Second cover 68 First Cover 78 Upper bolt 80 Lower bolt

Claims (2)

A hermetic container includes a drive element and first and second rotary compression elements driven by a rotation shaft of the drive element, the second rotary compression element on the drive element side, the first rotary compression In a rotary compressor comprising an element disposed on the side opposite to the drive element,
First and second cylinders constituting the first and second rotary compression elements;
First and second rollers that are fitted into first and second eccentric portions formed on the rotating shaft and eccentrically rotate in the first and second cylinders;
An intermediate partition member interposed between the cylinders to close the openings of both cylinders;
The first cylinder and the second cylinder each have an opening on the side opposite to the drive element of the first cylinder and an opening on the drive element side of the second cylinder, and have bearings for the rotating shaft. A support member of
A first cover and a second cover provided outside the bearings of the first and second support members, respectively, for forming a discharge silencing chamber between each support member;
A plurality of bolts inserted from the first cover side for assembling the first and second rotary compression elements;
Each of the bolts penetrates the first cover, the first support member, the first cylinder, the intermediate partition member, and the second cylinder, and is screwed into the second support member. A rotary compressor characterized by that.   The refrigerant compressed by the first rotary compression element is compressed by the second rotary compression element and discharged into the sealed container, and at least the vicinity of the suction passage of the second rotary compression element and the rotary shaft 2. The rotary compressor according to claim 1, wherein the bolt is screwed at a position substantially opposite to the suction passage.

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