JP2004036568A - Valve structure and compressor provided with it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a valve structure and a compressor provided with it excellent in reliability against a foreign matter while inhibiting a gap volume of a delivery port. <P>SOLUTION: The valve structure is provided on a compressor 100 for compressing and delivering CO<SB>2</SB>as an operation fluid and has a partition plate 140 for partitioning an operation chamber 152 and a delivery chamber 153; a delivery port 141 opened to the operation chamber 152 side of the partition plate 140; a delivery flow passage 142 communicated with the delivery port 141, having a large diameter, approximately concentrically arranged and opened to the delivery chamber 153 side of the partition plate 140; a valve element 161 urged to the operation chamber 152 side at a seal surface 143 formed at the delivery port 141 and the delivery flow passage 142. A groove part 144 recessed toward the operation chamber 152 side is provided on an outer peripheral side of the seal surface 143. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a valve structure suitable for being applied to a refrigeration cycle apparatus using CO2 as a refrigerant, and a compressor including the same.
[0002]
[Prior art]
As a technique related to a conventional valve structure of a compressor, there is known a technique disclosed in Japanese Patent Application Laid-Open No. H8-319973. This valve structure is applied to a discharge valve, in which a valve body and a seal surface are each formed as a curved rotary surface, and when both come into contact, a line contact seal is formed.
[0003]
As a result, the clearance volume (dead volume) of the discharge port portion is made substantially zero, and the re-expansion loss is reduced.
[0004]
[Problems to be solved by the invention]
In recent years, a refrigeration cycle device using CO2 having a lower global warming coefficient as a refrigerant due to environmental problems has been put to practical use. Since this refrigeration cycle apparatus is operated under high pressure conditions exceeding the critical pressure, the volume flow rate is very small, and the effect of the re-expansion loss due to the clearance volume on the compressor becomes very large. Naturally, it is important for the compressor to ensure the strength of each member that can withstand high pressure conditions.
[0005]
Therefore, in a compressor using CO2 as a refrigerant, the diameter of the discharge passage (hole diameter) for accommodating the valve body of the discharge valve is made as small as possible based on the above-described conventional technology capable of reducing the gap volume, in order to secure the strength. According to this, it is conceivable that the valve body itself can be made smaller. However, as the valve structure is reduced in size, there is a concern that foreign matter generated inside the refrigeration cycle device and inside the compressor itself may be easily caught on the valve body, hindering the operation of the valve body, and eventually causing the performance of the compressor to deteriorate. Is done.
[0006]
In view of the above problems, an object of the present invention is to provide a valve structure which is excellent in reliability against foreign matters while suppressing a clearance volume of a discharge port portion, and a compressor having the same.
[0007]
[Means for Solving the Problems]
The present invention employs the following technical means to achieve the above object.
[0008]
According to the first aspect of the present invention, the partition plate (140) is provided in the compressor (100) that compresses and discharges CO2 as a working fluid, and partitions the working chamber (152) and the discharge chamber (153). And a discharge port (141) that opens to the working chamber (152) side of the partition plate (140), and communicates with the discharge port (141). A working chamber (152) is formed by a discharge flow path (142) opening to the discharge chamber (153) side of the discharge flow path (140) and a seal surface (143) formed at the boundary between the discharge port (141) and the discharge flow path (142). In the valve structure having the valve body (161) biased to the side, a groove (144) is provided on the outer peripheral side of the sealing surface (143) toward the working chamber (152) side. And
[0009]
Thus, after the valve element (161) is opened and foreign matter flows out of the discharge port (141), when the valve element (161) closes, foreign matter near the valve element (161) is absorbed into the groove (144). In addition, since it is hard to be caught between the sealing surface (143) and the valve element (161), the reliability of the function of the valve element (161) can be improved.
[0010]
Further, since the sealing surface (143) of the valve element (161) is formed between the projecting port (141) in the partition plate (140) and the discharge flow path (142), the volume of the discharge port (141), that is, the capacity of the discharge port (141). The clearance volume can be easily reduced, and the re-expansion loss can be reduced.
[0011]
Note that the valve structure has a simple configuration, so that the discharge port (141), the discharge flow path (142), and the valve body (161) can be easily miniaturized, and the thickness of the partition plate (140) is ensured. Thus, the strength under high pressure conditions using CO2 as a refrigerant can be sufficiently ensured.
[0012]
According to the invention described in claim 2, at least one of the width (L) dimension and the depth (D) dimension of the groove (144) is set to be larger than the lift amount (d) when the valve body (161) is opened. It is characterized by having.
[0013]
As a result, foreign matter that can flow out of the valve body (161) can be reliably absorbed by the groove (144), so that the reliability of the function of the valve body (161) can be further improved.
[0014]
A compressor provided with the valve structure (160) according to any one of claims 1 and 2, as in the invention according to claim 3, wherein the valve according to the arrangement or the number of the working chambers (152). In the case of having a plurality of structures (160), the probability of foreign matter being caught is high, and therefore, it is particularly effective to apply this valve structure (160).
[0015]
According to the fourth aspect of the present invention, the opening areas of the discharge ports (141) of the plurality of valve structures (160) that open to the valve element (161) side are all formed to be the same, and the valve elements (161) are all the same. It is characterized by being set as specifications.
[0016]
Accordingly, even when the inner diameter of the discharge port (141) is different, the valve opening pressure applied to the valve element (161) can be made the same, so that the valve element (161) can be shared and inexpensive. can do.
[0017]
Note that the reference numerals in parentheses of the above means indicate the correspondence with specific means described in the embodiment described later.
[0018]
BEST MODE FOR CARRYING OUT THE INVENTION
(1st Embodiment)
A first embodiment of the present invention will be described with reference to FIGS. The compressor 100 is applied to a refrigeration cycle device (not shown) using CO2 as a refrigerant. Here, the compressor 100 is an electric compressor in which a compressor unit 130 is operated by a motor unit 120 incorporated therein.
[0019]
The motor section 120 and the compressor section 130 are housed in a housing 110 as a sealed container formed by welding a front housing 111, a middle housing 112, and an end housing 113 to each other. The front housing 111 is provided with a suction port 111a through which the refrigerant is sucked.
[0020]
A support plate 114 and a frame 115 to which bearings 132 and 133 are fixed are provided on the front housing 111 side and the intermediate portion in the middle housing 112, respectively, and the drive shaft 131 is rotatably supported by the bearings 132 and 133. Have been.
[0021]
The motor section 120 includes a rotor section 121 and a stator section 122. The rotor part 121 is fixed to the drive shaft 131, and the stator part 122 is fixed to the inner peripheral surface of the middle housing 112 on the outer peripheral side of the rotor part 121 by press fitting. When power from an external power supply (not shown) is supplied to the stator unit 122, the drive shaft 131 is driven to rotate with the rotation of the rotor unit 121. The support plate 114 is provided with a flow passage 114a through which the refrigerant sucked from the suction port 111a flows through a space in the middle housing 112 in which the motor unit 120 is housed.
[0022]
The compressor section 130 forms a well-known scroll compressor having a movable scroll 135 and a fixed scroll 140. The fixed scroll 140 is fixed to the opposite side of the motor portion in the middle housing 112, and a movable scroll 135 is arranged to mesh with the fixed scroll 140.
[0023]
An eccentric portion 131 a provided at the tip of the drive shaft 131 is inserted into the movable scroll 135 on the side opposite to the fixed scroll via a bearing 134. Then, the orbiting scroll 135 revolves with respect to the fixed scroll 140 by rotation of the drive shaft 131 by a rotation preventing mechanism (not shown).
[0024]
A suction chamber 151 is formed on the outer peripheral side between the scrolls 135 and 140, and a working chamber 152 is formed toward the center. The frame 114 has a flow passage 115 a through which the refrigerant flowing into the space in which the motor unit 120 is housed flows through the suction chamber 151.
[0025]
A discharge chamber 153 connected to the discharge port 112a is formed in the fixed scroll 140, and a discharge valve section (valve structure) 160, which is a feature of the present invention, is provided between the working chamber 152 and the discharge chamber 153. Has been. In the scroll-type compressor 100, discharge valve portions 160 are provided at a total of three places: a central portion of the fixed scroll 140 where the compressed refrigerant from the two working chambers 152 merges and a predetermined portion in the two working chambers 152. The central discharge valve section 160 is a main discharge valve section 160a, and the other two are sub discharge valve sections 160b.
[0026]
Since the basic configuration of the discharge valve section 160 is the same for all three, the main discharge valve section 160a at the center will be described in detail with reference to FIGS.
[0027]
The discharge valve section 160 includes a valve body 161, a spring 162, and a stopper 163 provided in the discharge channel 142 among the discharge port 141 and the discharge channel 142 provided as circular holes in the fixed scroll 140. Note that the fixed scroll 140 corresponds to a partition plate that partitions the working chamber 152 and the discharge chamber 153 in the present invention.
[0028]
The discharge port 141 is a small-diameter hole that opens to the working chamber 152 side, and the radial dimension and the axial dimension are set as small as possible. The discharge channel 142 is a channel communicating with the discharge port 141 and opening to the discharge chamber 153 side. The inner diameter of the discharge channel 142 is set to be larger than that of the discharge port 141, and the discharge channels 142 are arranged substantially concentrically.
[0029]
A seal surface 143 is formed at the boundary between the discharge port 141 and the discharge flow path 142, and a disc-shaped valve body 161 is urged toward the working chamber 152 by a spring 162 on the seal surface 143 to contact the seal surface 143. In contact. Further, a stopper 163 is provided on the side opposite to the discharge port of the valve body 161 so as to regulate a lift amount d when the valve body 161 is opened by a predetermined discharge pressure from the working chamber 152.
[0030]
On the outer periphery of the valve body 161, a plurality of guide portions 161a inscribed in the discharge flow path 142 and a cutout portion 161b for flowing the refrigerant are formed. The depth dimension h and the width dimension w of the notch 161b are set to be larger than the lift amount d, respectively.
[0031]
A groove 144 is provided on the outer peripheral side of the seal surface 143 so as to be recessed toward the working chamber 152. Both the width dimension L and the depth dimension D of the groove 144 are set to be larger than the lift amount d as in the case of the guide 161a and the notch 161b of the valve body 161. Note that one of the width dimension L and the depth dimension D may be set to be larger than the lift amount d.
[0032]
Further, as shown in FIG. 4, since the discharge flow rate of the refrigerant is different between the main discharge valve portion 160a and the sub discharge valve portion 160b, the inner diameter of each discharge port 141 is set to satisfy φA1> φA2. . That is, the diameter of the discharge port on the side of the main discharge valve portion 160a having a large discharge flow rate is increased. However, the opening area (φB in the opening diameter) of the discharge port 141 opening on the valve body 161 side is the same for both the main and sub discharge valve portions 160a and 160b, and the valve body 161, the spring 162, and the stopper 163 The discharge valves 160a and 160b have the same specifications.
[0033]
Next, operations and effects based on the above configuration will be described. In the compressor 100, the movable scroll 135 is revolved by the driving of the motor unit 120, and compresses the refrigerant flowing into the suction chamber 151 through the suction port 111 a and the flow passages 114 a and 115 a in the working chamber 152. At this time, the refrigerant circulates through the motor unit 120, so that the motor unit 120 is cooled.
[0034]
Then, when the refrigerant compressed in the working chamber 152 reaches a predetermined discharge pressure, the valve bodies 161 of the discharge valve portions 160a and 160b are regulated by the lift amount d and open, and the refrigerant is opened by the discharge port 141 and the cutoff of the valve body 161. The liquid is discharged from the discharge port 112a through the notch 161b, the discharge channel 142, and the discharge chamber 153.
[0035]
By the way, in the refrigeration cycle apparatus and the inside of the compressor 100 itself, foreign matters such as fine chips and chips generated when molding each member are present and flow together with the refrigerant. In the present invention, since the groove 144 is formed on the outer peripheral side of the seal surface 143, the foreign matter near the valve body 161 when the valve body 161 closes after the valve body 161 is opened and foreign matter flows out from the discharge port 141. Is absorbed in the groove 144, so that it is hard to be caught between the sealing surface 143 and the valve body 161, and the reliability of the function of the valve body 161 can be improved.
[0036]
Here, the width dimension L and the depth dimension D of the groove 144 are both larger than the lift amount d of the valve body 161, so that the foreign matter that can flow out of the valve body 161 can be reliably absorbed in the groove 144. I have.
[0037]
In addition, the valve body 161, the spring 162, and the stopper 163 are common to the plurality of set discharge valve portions 160a and 160b, with the opening area (opening diameter φB) of the discharge port 141 opening toward the valve body 161 being the same. The specifications make it possible to respond cheaply.
[0038]
This means that, even when the inner diameters of the discharge ports 141 are different, by making the opening areas opened to the discharge valve 161 the same, the valve opening force applied to the valve body 161 is made the same, thereby enabling commonality. .
[0039]
Since the sealing surface 143 of the valve body 161 is formed between the projecting port 141 in the fixed scroll 140 and the discharge channel 142, the volume of the discharge port 141, that is, the gap volume can be easily reduced, and the re-expansion loss can be reduced. Can be reduced.
[0040]
In addition, the valve structure has a simple configuration, the size of the discharge port 141, the discharge flow path 142, and the valve body 161 can be easily reduced. The strength under the conditions can be sufficiently secured.
[0041]
(2nd Embodiment)
FIG. 5 shows a second embodiment of the present invention. In the second embodiment, the valve body 161 is formed in a hemispherical shape, and a sealing surface 143 is formed by opening the discharge port 141 so that the valve body 161 side is opened in a conical shape. A groove 144 is formed on the outer peripheral side of the seal surface 143.
[0042]
Thus, as in the first embodiment, the foreign matter is prevented from being caught by the groove 144, and sealing at a line on the circumference where the valve body 161 contacts the discharge port 141 is enabled. Can be further reduced to reduce the re-expansion loss.
[0043]
(Other embodiments)
In the first and second embodiments, the scroll type compressor unit 130 has been described. However, the present invention is not limited to this, and another type of compressor unit 130 may be used. FIG. 6 shows an example in which the compressor section 130 has two compression sections 130a and is applied to a two-stage rotary type in which the pressure is increased and compressed. Here, two rotors 136 are provided on the drive shaft 131, and a discharge valve section 160 is provided between each working chamber 152 and the discharge chamber 153. The valve body 161, the spring 162, and the stopper 163 forming the two discharge valve portions 160 have the same specifications as in the first embodiment.
[0044]
Other than the multi-stage compression, a multi-cylinder rotary type may be used, and a multi-cylinder piston type such as a swash plate type is also applicable. In the case where there are a plurality of cylinders and a plurality of discharge valve portions 160 are provided in accordance therewith, the probability of being caught by foreign matter increases, and therefore, it is particularly effective to apply the valve structure of the present invention.
[Brief description of the drawings]
FIG. 1 is a sectional view showing a compressor according to a first embodiment of the present invention.
FIG. 2 is an enlarged view showing a discharge valve section in FIG.
FIG. 3 is an arrow view showing the valve body from a direction A in FIG. 2;
FIG. 4 is an enlarged view showing main and sub discharge valve portions.
FIG. 5 is an enlarged view showing a discharge valve section according to a second embodiment of the present invention.
FIG. 6 is a sectional view showing a compressor according to another embodiment.
[Explanation of symbols]
100 Compressor 140 Fixed scroll (partition plate)
141 discharge port 142 discharge passage 143 sealing surface 144 groove 152 working chamber 153 discharge chamber 161 valve body

Claims (4)

A compressor (100) that compresses and discharges CO2 as a working fluid,
A partition plate (140) for partitioning between the working chamber (152) and the discharge chamber (153);
A discharge port (141) opening toward the working chamber (152) of the partition plate (140);
A discharge flow path (142) communicating with the discharge port (141), disposed substantially concentrically with a large diameter, and opening to the discharge chamber (153) side of the partition plate (140);
A valve structure having a valve body (161) urged toward the working chamber (152) by a sealing surface (143) formed at a boundary between the discharge port (141) and the discharge flow path (142). ,
A valve structure characterized in that a groove (144) is provided on the outer peripheral side of the sealing surface (143) toward the working chamber (152). At least one of a width (L) dimension and a depth (D) dimension of the groove (144) is set to be larger than a lift amount (d) when the valve body (161) is opened. Item 2. The valve structure according to Item 1. A compressor comprising a valve structure (160) according to any of the preceding claims.
A compressor having a plurality of the valve structures (160) according to the arrangement or number of the working chambers (152). The opening areas of the discharge ports (141) of the plurality of valve structures (160) that open to the valve element (161) side are all formed to be the same,
The compressor according to claim 3, wherein all the valve bodies (161) are set to have the same specification.

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