JP2008291658A - Scroll compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an efficient and reliable scroll compressor keeping sliding parts of a turning scroll and a fixed scroll under a good lubricating condition even in the compression space in which pressure is higher than the pressure in an intake chamber. <P>SOLUTION: A second communication passage 24 communicating to a tip 9c of a turning scroll lap 9a is provided in an end plate 9b of the turning scroll 9 as an oil supply passage supplying lubricating oil from an oil pocket at a bottom part of a hermetic vessel 1, a roughly involute shape groove 25 communicating to the second communication passage 24 is provided on the tip 9c of the turning scroll lap 9a, and a pair of arc grooves 26 opening to both side compression chambers 30a, 30b opposing to the roughly involute shape groove 25 and the lap are provided. Consequently, the sliding part of the turning scroll 9 and the fixed scroll 6 can be maintained under the good lubrication condition even in the compression space 30a, 30b in which pressure is higher than pressure in the intake chamber 13, the efficient and reliable scroll compressor can be provided. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a scroll compressor used for an air conditioner, a refrigerator, a blower, a water heater, and the like.

  In conventional scroll compressors, there is a need to improve the efficiency and reliability by reducing mechanical loss by improving the lubrication of the sliding surface with a mechanism that supplies lubricating oil to the sliding part of the fixed scroll and the orbiting scroll. It was.

FIG. 8 is a plan view of a conventional scroll compressor, and FIG. 9 is a plan view of the fixed scroll as viewed from the scroll wrap side. As shown in FIGS. 8 and 9, an annular groove 120 and an outer groove 122 extending outward from the outer periphery of the annular groove 120 are formed on the end plate 105a of the orbiting scroll so that the back pressure chamber and the suction chamber 124 communicate with each other. A pressure intermediate between the pressure and the intake pressure is applied to the groove 122 and passes from the back pressure chamber to the suction chamber 124 through the outer groove 122 of the orbiting scroll 105, the annular groove 120, the annular groove 121 of the fixed scroll, and the inner groove 123 in this order. Lubricating the fixed and orbiting scroll end plates 104a and 105a and the lap by the flow of the lubricating oil entering, and recirculating from the discharge port 114, the mechanical loss from the improvement of the lubrication state of the sliding portion of the fixed scroll 104 and orbiting scroll 105 Since the oil supply mechanism has a simple structure, oil is quickly supplied to the sliding part immediately after operation, resulting in higher reliability. Providing a scroll compressor that can have been disclosed with (e.g., see Patent Document 1).
Japanese Patent Application Laid-Open No. 8-200262

  However, in the conventional configuration, since oil flows from the back pressure chamber to the suction chamber while being lubricated, a large amount of oil enters the suction chamber, but almost no oil is supplied to the compression space whose pressure is higher than that of the suction chamber. There is a problem in reliability such as insufficient lubrication of the sliding part of the orbiting scroll and fixed scroll, resulting in a decrease in efficiency due to an increase in sliding loss and a possibility of increased wear due to interference between laps. Was.

  The present invention solves such a conventional problem, and an object thereof is to provide a highly efficient and highly reliable compressor.

  In order to solve the above problems, the present invention provides a first communication passage in the orbiting scroll end plate for supplying lubricating oil from an oil reservoir and a second communication passage communicating with the end of the orbiting scroll wrap, and the second communication passage. A substantially involute-shaped groove that communicates with the passage is provided at the tip of the orbiting scroll wrap, and a pair of arc-shaped grooves that open to the compression chambers on both sides facing the substantially involute-shaped groove and the wrap are provided.

  By adopting the oil supply configuration as described above, it is possible to maintain good lubrication of the sliding portion of the orbiting scroll and the fixed scroll even in a compression space where the pressure is higher than that of the suction chamber, and the efficiency is reduced due to an increase in sliding loss. Burn-in and abnormal wear due to interference between laps can be avoided.

  The scroll compressor of the present invention can provide a highly efficient and highly reliable compressor by improving the lubrication of the sliding portions of the fixed scroll and the orbiting scroll.

  1st invention has the oil reservoir which stores lubricating oil in a bottom part, arrange | positions the internal motive of the airtight container which discharge pressure acts, and the compression mechanism driven with this electric motor, the compression mechanism is fixed to a fixed scroll, fixed A orbiting scroll that meshes with the scroll to form a plurality of compression chambers, a rotation restraint component that prevents the orbiting scroll from rotating and only turns, a crankshaft that orbits the orbiting scroll, and a main shaft formed on the crankshaft Orbiting drive, which includes a bearing part having a main bearing for supporting the orbiting scroll, and engages an eccentric drive engaging portion provided on the crankshaft on the back of the end plate on the side opposite to the orbiting of the orbiting scroll to drive the orbiting scroll. An engaging portion is provided, and the pressure acting on the rear surface of the end plate on the outside of the pivot drive engaging portion is lower than the discharge pressure acting on the center portion of the rear surface of the end plate and the discharge pressure acting on the outer periphery of the rear surface of the end plate A sliding partition ring is provided to divide into force, and high-pressure lubricating oil is supplied from the oil reservoir to the center of the back of the end plate, and the back formed in the space outside the center of the end of the end plate and the sliding partition. A first communication passage that communicates with the pressure chamber and a second communication passage that communicates the tip of the orbiting scroll wrap are provided inside the end plate of the orbiting scroll, and communicates with the second communication passage at the tip of the orbiting scroll wrap. A substantially involute-shaped groove is provided, and a pair of arc grooves are formed in the groove with a diameter larger than the width of the orbiting scroll wrap and open to the compression chambers on both sides facing the wrap.

  By adopting such a configuration, it is possible to maintain good lubrication of the sliding portions of the orbiting scroll and the fixed scroll even in a compression space where the pressure is higher than that of the suction chamber. It is possible to avoid seizure and abnormal wear due to interference. In addition, the improved oil seal performance reduces efficiency due to refrigerant leakage between the high-pressure compression chamber and the low-pressure compression chamber that are formed before and after the lap sliding part, and improves lap processing accuracy and assembly accuracy. When the temperature is low, it is possible to suppress a decrease in efficiency due to leakage of the refrigerant from the gap formed between the wraps.

  In a second aspect of the present invention, a pair of arc grooves that open to the compression chambers on both sides facing the wrap are provided at the winding end of the substantially involute-shaped groove that communicates with the second communication passage at the tip of the orbiting scroll wrap. As a result, the pressure difference between the opening of the communication passage at the tip of the lap and the opening of the arc groove can be increased, and the flow rate of the lubricating oil flowing through the substantially involute groove can be increased and stabilized. As a result, the oil seal performance of the nearby compression chamber is improved, and high efficiency and high reliability of the compressor can be achieved.

  3rd invention makes deep the depth of a pair of circular arc groove opened to the compression chamber of the both sides which oppose a lap with respect to the substantially involute-shaped groove depth connected to a 2nd communication path at the turning scroll wrap front-end | tip. With this configuration, the lubricating oil flowing out from the opening of the communication passage at the tip of the lap does not stay in the substantially involute-shaped groove, and new lubricating oil can always be supplied from the arc groove to the compression chamber space. , Can maintain the lubrication ability.

  In the fourth aspect of the invention, by forming a pair of arc grooves opened in the compression chambers on both sides facing the orbiting scroll lap by end milling, simultaneous processing with the tip of the wrap becomes possible, contributing to improvement in productivity. be able to. In addition, severe depth control in circular arc grooving is possible, and compressor performance can be stabilized by controlling the amount of oil supplied to the compression chamber.

  According to a fifth aspect of the present invention, in the scroll compressor according to any one of the first to fourth aspects, the load applied to the sliding surfaces of the orbiting scroll and the fixed scroll due to an increase in the differential pressure by using carbon dioxide as the refrigerant. High efficiency and high reliability can be provided even in the case where the current becomes very large.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1)
FIG. 1 is a longitudinal sectional view of a scroll compressor according to a first embodiment of the present invention, FIG. 2 is a plan view of the orbiting scroll viewed from a wrap direction, and FIG.

  In the figure, a compression mechanism and a stator 3b of an electric motor that drives the compression mechanism are fixed inside a sealed container 1 having a discharge pressure atmosphere having an oil reservoir for storing lubricating oil at the bottom, and the compression mechanism is driven by a rotor 3a of the electric motor. The crankshaft 4 is connected, and the periphery of the compression mechanism of the sealed container 1 is used as an oil reservoir. The compression mechanism includes a fixed scroll 6, a turning scroll 9 that meshes with the fixed scroll 6 to form a plurality of compression chambers 11, a rotation restraining component that prevents the turning of the turning scroll 9 and makes only turning, and this An orbiting shaft 4b provided on the opposite side of the orbiting scroll 9, an eccentric bearing 10 provided inside the main shaft 4a of the crankshaft 4 and into which the orbiting shaft 4b is fitted, and a main shaft that supports the main shaft 4a of the crankshaft 4. A main bearing part 5 having an axial movement restricting flat surface portion that restricts the axial movement of the orbiting scroll 9 with a small gap from the back surface of the end plate 9b of the bearing 14 and the orbiting scroll 9 is disposed. A space 20 where a discharge pressure applied to the central portion of the gas pressure applied to the end plate 9b acts on the axial movement restriction plane portion, and a back pressure chamber where a pressure lower than the discharge pressure applied to the outer periphery of the rear surface of the end plate 9b acts. A sliding partition ring 16 for partitioning with 18 is disposed.

  Inside the orbiting scroll 9, there are a first communication passage 24a for connecting the discharge pressure working space 20 inside the sliding partition ring 16 and the back pressure chamber 18 via a throttle mechanism 21, and a first communication passage 24a. Is provided with a second communication passage 24b that communicates with the orbiting scroll wrap tip 9c, and a substantially involute-shaped groove 25 that communicates with the second communication passage 24b at the wrap tip 9c of the orbiting scroll, and a substantially involute. A pair of circular-arc grooves 26 that are connected to the shape groove 25 and have a diameter larger than the width of the orbiting scroll wrap and open to the compression chambers 30a and 30b on both sides facing the wrap are provided.

  The crankshaft 4 is also provided with an oil supply passage 7 penetrating through the crankshaft 4. The end surface of the oil supply passage 7 on the side opposite to the compression mechanism is an oil reservoir through the oil pump 8, and the end surface on the compression mechanism side is the orbiting scroll end plate 9b. It is configured to communicate with the space 20 where the discharge pressure at the center of the back surface acts.

  By adopting such a configuration, the lubricating oil guided from the oil reservoir to the space 20 where the discharge pressure at the center of the rear surface of the orbiting scroll end plate 9b acts by the oil pump 8 or the like is one side from the first communication passage 24a. Via a throttle mechanism 21, a back pressure chamber 18 formed by being surrounded by the fixed scroll 6 and the main bearing part 5, and a back pressure adjusting mechanism 22 having a function of pressing the orbiting scroll 9 against the fixed scroll 6. Then, it is guided to the suction chamber 13. The other flows into the substantially involute-shaped groove 25 of the orbiting scroll wrap tip 9c via the second communication passage 24b communicating with the orbiting scroll wrap tip 9c, and a pair of arc grooves 26 communicating with the groove 25. From the above, by supplying appropriate amounts to the compression chambers 30a and 30b on both sides whose pressure is higher than that of the suction chamber 13, lubrication of the sliding portions of the orbiting scroll 9 and the fixed scroll 6 can be maintained well, and sliding loss Reduction in efficiency due to increase, seizure and abnormal wear due to excessive interference between laps can be avoided. In addition, an appropriate amount of lubricating oil is supplied to both the compression chambers 30a and 30b to improve the oil seal performance, so that the refrigerant between the high pressure compression chamber and the low pressure compression chamber formed upstream and downstream of the lap sliding portion. It is also possible to suppress a decrease in efficiency due to leakage of the refrigerant, and a decrease in efficiency due to leakage of refrigerant from the gap formed between the laps when the lapping accuracy and assembly accuracy are low. The amount of oil supplied to the compression chamber can be controlled by appropriately selecting the dimensions (length, width, depth etc) of the substantially involute-shaped groove 25 and the pair of arc grooves 26, If the dimensions are designed so that the amount of oil supply is increased within a range where viscosity loss and refrigerant overheating loss do not increase, a highly efficient and highly reliable scroll compressor can be provided.

(Embodiment 2)
Further, as shown in FIG. 4, at the end of winding 25 of the substantially involute-shaped groove 25 communicating with the second communication passage 24b at the orbiting scroll wrap tip 9c, the compression chambers 30a and 30b on both sides facing the wrap are opened. By providing the pair of arc grooves 26, the pressure difference between the opening portion of the second communication passage 24b of the orbiting scroll wrap tip 9c and the opening end of the arc groove 26 can be increased, and the substantially involute shape is obtained. The flow rate of the lubricating oil flowing through the groove 25 can be increased and stabilized. As a result, the oil seal performance of the nearby compression chamber is improved, and high efficiency and high reliability of the compressor can be achieved.

(Embodiment 3)
Further, as shown in FIGS. 5 and 6, the compression chambers 30a on both sides facing the lap with respect to the groove depth of the substantially involute-shaped groove 25 communicating with the second communication passage 24b at the orbiting scroll wrap tip 9c, By making the depth of the pair of arc grooves 26 opened to 30b deeper, the lubricating oil flowing in from the opening of the second communication passage 24b of the orbiting scroll wrap tip 9c is allowed to enter the bottom of the substantially involute groove 25. A new lubricating oil can always be supplied from the arc groove to the compression chamber space without staying, and the lubricating ability can be maintained.

(Embodiment 4)
Further, as shown in FIG. 7, a pair of arc grooves 26 opened to the compression chambers 30a and 30b on both sides facing the orbiting scroll wrap 9b are formed by end milling, so that Simultaneous processing becomes possible, which can contribute to the improvement of productivity. In addition, severe depth control in arc groove machining is possible, and a highly efficient and highly reliable scroll compressor can be provided by controlling the amount of oil supplied to the compression chamber.

  Further, by using carbon dioxide as a refrigerant, high efficiency and high reliability can be provided even when the load applied to the sliding surfaces of the orbiting scroll and the fixed scroll becomes very large due to an increase in differential pressure. Can do.

  As described above, the scroll compressor according to the present invention provides oil to the sliding part of the orbiting scroll and the fixed scroll by providing the substantially involute-shaped groove and the pair of arc grooves at the tip of the orbiting scroll wrap. In addition to air conditioner compressors that use HFC refrigerants and HCFC refrigerants, air conditioners and heat pump water heaters that use natural refrigerant carbon dioxide, etc. It can be applied to other uses.

The longitudinal cross-sectional view of the scroll compressor in embodiment of this invention The top view which looked at the turning scroll in Embodiment 1 of this invention from the lap side Partial enlarged view of a substantially involute-shaped groove in the first embodiment of the present invention Partial enlarged view of the substantially involute-shaped groove in the second embodiment of the present invention Partial enlarged view of a substantially involute-shaped groove in Embodiment 3 of the present invention AA arrow view in FIG. End mill processing explanatory drawing in Embodiment 4 of the present invention A plan view of the orbiting scroll of a conventional scroll compressor as seen from the lap side Plan view of fixed scroll of conventional scroll compressor viewed from lap side

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Sealed container 2 Discharge pipe 3 Motor 3a Rotor 3b Stator 4 Crankshaft 4a Main shaft part 4b Turning shaft part 4c Subshaft part 5 Main bearing parts 6 Fixed scroll 6a Fixed scroll end plate 6b Fixed scroll wrap 7 Oil supply passage 8 Oil supply pump device DESCRIPTION OF SYMBOLS 9 Orbiting scroll 9a Orbiting scroll lap 9b Orbiting scroll end plate 9c Orbiting scroll wrap tip 10 Orbiting bearing 11 Compression space 12 Discharge port 13 Suction chamber 14 Main bearing component 16 Sliding partition ring 17 Back chamber 18 Back pressure chamber 19 Sub bearing 20 Discharge pressure 21 throttle portion 22 back pressure adjustment mechanism 22a oil supply passage 23 check valve device 23a reed valve 23b valve retainer 24a first communication passage 24b second communication passage 25 substantially involute groove 26 pair of arc grooves 30ab higher than suction pressure 40 End mill 41 End mill processing locus 104 Fixed scroll 104a Fixed scroll end plate 104b Fixed scroll wrap 105 Orbiting scroll 105a Orbiting scroll end plate 105b Orbiting scroll wrap 114 Discharge port 120 Annular groove of end plate 5a 121 End plate 4a annular groove 122 outer groove 123 inner groove 124 suction chamber

Claims (5)

There is an oil reservoir for storing lubricating oil at the bottom, and an electric motor and a compression mechanism driven by this electric motor are arranged inside a sealed container on which discharge pressure acts. The compression mechanism meshes with the fixed scroll and the fixed scroll. A rotating scroll that forms a plurality of compression chambers, a rotation restraint component that prevents the rotating scroll from rotating and only rotates, a crank shaft that drives the rotating scroll to rotate, and a main shaft formed on the crank shaft are supported. Orbiting drive, which is configured to include a bearing component having a main bearing that engages with an eccentric drive engagement portion provided on the crankshaft on the back surface of the orbiting scroll on the side opposite to the lap. An engagement portion is provided, and a pressure acting on the back surface of the end plate on the outer side of the turning drive engagement portion is applied to a discharge pressure acting on the center portion of the back surface of the end plate and an outer periphery of the back surface of the end plate. A sliding partition ring that divides into a pressure lower than the discharge pressure to be supplied, supplies high-pressure lubricating oil from the oil reservoir to the central part of the rear face of the end plate, and outwards from the central part of the rear face of the end plate and the sliding partition ring A first communication passage that communicates with the back pressure chamber formed in the space and the tip of the orbiting scroll wrap, and a second communication passage that communicates with the first communication passage and has the scroll wrap tip at the open end. In the end plate of the orbiting scroll, a substantially involute-shaped groove communicating with the second communication passage at the end of the orbiting scroll wrap, and having a diameter larger than the width of the orbiting scroll wrap in the groove, A scroll compressor comprising a pair of arc grooves opened in the compression chambers on both sides facing the wrap. The scroll compressor according to claim 1, wherein the pair of circular arc grooves are provided at a winding end of the substantially involute-shaped groove. 3. The scroll compressor according to claim 1, wherein a depth of the pair of arc grooves is deeper than that of the substantially involute-shaped grooves. The scroll compressor according to any one of claims 1 to 3, wherein the pair of arc grooves are formed by end milling. The scroll compressor as described in any one of Claims 1-4 which used the carbon dioxide which is a high pressure refrigerant | coolant as a working fluid.

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