637080 KPO-2531
DESCRIPTION
Title of Invention
COMPRESSOR AND METHOD FOR MANUFACTURING COMPRESSOR
Technical Field
5 [0001]
The present invention relates to a compressor and a method for manufacturing a compressor. Background Art [0002]
10 There has been proposed a compressor including: a suction connection
pipe having one end connected to a cylinder of a compression mechanism; a joining pipe that is connected to a sealed container and into which the suction connection pipe is inserted; and a suction pipe to which the other end of the suction connection pipe is connected (see, for example, Patent Literature 1). In
15 the compressor disclosed in Patent Literature 1, the joining pipe is made of
copper, and the suction connection pipe and the joining pipe are fixed to each other by brazing. [0003]
There has also been proposed a compressor including: a suction
20 connection pipe connected to a cylinder of a compression mechanism; and a
sealed container having an opening into which the suction connection pipe is inserted and to which the suction connection pipe is joined (see, for example, Patent Literature 2). In the compressor disclosed in Patent Literature 2, a flange is formed on the outer circumferential surface of the suction connection pipe to
25 protrude from the inner circumferential side to the outer circumferential side.
The flange of the suction connection pipe and a part of the sealed container
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where the opening is formed are joined by projection welding (resistance
welding).
Citation List
Patent Literature
[0004]
Patent Literature 1: Japanese Unexamined Patent Application Publication No. 11-182434 (see, for example, Fig. 1)
Patent Literature 2: Japanese Examined Patent Application Publication No. 7-117043 (see, for example, Fig. 1) Summary of Invention Technical Problem [0005]
As for the compressor disclosed in Patent Literature 1, the suction connection pipe and the joining pipe are joined by gas brazing. For performing gas brazing, a copper material is used in the joining portion between the suction connection pipe and the joining pipe in view of the efficiency and quality. Therefore, it is necessary to apply copper plating to a part to be joined, that is, an end of the suction connection pipe, or to join a copper pipe to the end of the suction connection pipe in advance, for example. Thus, the manufacturing cost of the compressor is increased. [0006]
Further, as for the compressor disclosed in Patent Literature 2, an electrode is disposed at a position where the flange is formed, and thus resistance welding is performed. That is, resistance welding is performed while pressing the electrode against the flange, and hence the flange and the sealed container are pressed against each other. Therefore, since the flange and the sealed container are pressed against each other, the sealed container might be
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distorted. Further, since the suction connection pipe having the flange formed
thereon is connected to a compression element, the compression element might
also be distorted as the flange is pressed. Thus, in the compressor disclosed in
Patent Literature 2, the sealed container and the compression element are
5 distorted, resulting in a reduction in reliability.
[0007]
The present invention has been made to overcome the above problems, and aims to provide a compressor and a method for manufacturing a compressor capable of suppressing a reduction in reliability while reducing an increase in
10 manufacturing cost.
Solution to Problem [0008]
A compressor according to the present invention includes a sealed container; a compression element disposed in the sealed container and
15 configured to compress refrigerant; an electric motor element disposed in the
sealed container and configured to drive the compression element; a joining pipe made of iron, the joining pipe having one end connected to the sealed container; a suction connection pipe made of iron, the suction connection pipe being inserted in the joining pipe and having one end connected to the compression
20 element; and a suction pipe having one end connected to an other end of the
suction connection pipe, the suction connection pipe including an annular first protruding portion formed on the other end thereof and protruding from an inner circumferential side to an outer circumferential side, the first protruding portion of the suction connection pipe and an other end of the joining pipe being joined to
25 one another.
Advantageous Effects of Invention [0009]
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According to the compressor of the present invention, the suction
connection pipe that is made of iron and that connects the suction pipe and a
compression mechanism, and the joining pipe that is made of iron and into which
the suction connection pipe is inserted are joined. That is, the suction
5 connection pipe and the joining pipe are made of iron. Therefore, copper that is
more expensive than iron does not need to be used, making it possible to reduce an increase in manufacturing cost. [0010]
According to the compressor of the present invention, even in the case
10 where joining is performed by welding means, such as resistance welding, that
applies a force of pressing the suction connection pipe toward the sealed container, it is possible to inhibit the force from being applied to the compression container and the compression element. That is, the compressor according to the present invention includes the joining pipe. Therefore, upon joining the
15 suction connection pipe and the joining pipe, even when the suction connection
pipe is pressed toward the sealed container, it is possible to inhibit the suction connection pipe from being pressed directly against the sealed container. Thus, the pressing force is inhibited from being directly applied to the sealed container and the compression element.
20 Further, the compressor according to the present invention includes the
joining pipe. Thus, for example, when performing resistance welding, it is possible to perform resistance welding by pressing the suction connection pipe toward the sealed container while holding the joining pipe. Therefore, when the suction connection pipe is pressed toward the sealed container, the pressing
25 force is inhibited from being applied to the sealed container and the compression
element.
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Thus, since the compressor according to the present invention has a
configuration capable of suppressing the occurrence of distortion of the sealed
container and the compression element when resistance welding is performed for
joining, for example, it is possible to suppress a reduction in reliability.
5 Brief Description of Drawings
[0011]
[Fig. 1] Fig. 1 is a cross-sectional view schematically illustrating the
configuration of a compressor 100 according to Embodiment 1 of the present
invention.
10 [Fig. 2] Fig. 2 is a cross-sectional view schematically illustrating joining a
suction connection pipe 12 and a joining pipe 10 of the compressor 100 illustrated in Fig. 1.
[Fig. 3A] Fig. 3Ais a schematic diagram illustrating the configuration of the
joining pipe 10.
15 [Fig. 3B] Fig. 3B is a schematic diagram illustrating the configuration of the
suction connection pipe 12.
[Fig. 3C] Fig. 3C is a schematic diagram illustrating the configuration of a suction pipe 15.
[Fig. 3D] Fig. 3D is a schematic diagram illustrating a first weld portion.
20 [Fig. 4] Fig. 4 is a horizontal sectional view schematically illustrating the
configuration of electrodes (a first electrode 20 and a second electrode 21) for resistance welding for joining the suction connection pipe 12 and the joining pipe 10 illustrated in Fig. 2.
[Fig. 5A] Fig. 5A is a view schematically illustrating the configuration of the
25 second electrode 21 for resistance welding illustrated in Fig. 4.
[Fig. 5B] Fig. 5B is a perspective view schematically illustrating the configuration of the first electrode 20 for resistance welding illustrated in Fig. 4.
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[Fig. 5C] Fig. 5C is a side view schematically illustrating the configuration of the first electrode 20 for resistance welding illustrated in Fig. 4.
[Fig. 5D] Fig. 5D is a flowchart of manufacture of the compressor 100.
[Fig. 6] Fig. 6 is a schematic diagram illustrating a modification of the
5 joining pipe 10 of the compressor 100 according to Embodiment 1 of the present
invention, wherein an electrode receiving portion is formed in a tapered shape.
[Fig. 7] Fig. 7 is a cross-sectionai view schematically illustrating joining a
suction connection pipe 120 and a joining pipe 110 of a compressor 100
according to Embodiment 2 of the present invention.
10 [Fig. 8A] Fig. 8Ais a schematic diagram illustrating the configuration of the
joining pipe 110.
[Fig. 8B] Fig. 8B is a schematic diagram illustrating the configuration of the suction connection pipe 120.
[Fig. 9] Fig. 9 is a schematic diagram illustrating a modification of the
15 joining pipe 110 of the compressor 100 according to Embodiment 2 of the present
invention, wherein a projection is formed on the suction connection pipe 120.
[Fig. 10] Fig. 10 is a diagram illustrating a conventional example 1.
[Fig. 11] Fig. 11 is a diagram illustrating a conventional example 2.
Description of Embodiments
20 [0012]
Hereinafter, a compressor 100 according to embodiments of the invention
will be described with reference to the drawings. In the drawings including Fig.
1 to be referred to below, identical reference numerals denote identical or like
elements. This applies to the embodiments described below.
25 [0013]
Embodiment 1
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Fig. 1 is a cross-sectional view schematically illustrating the configuration
of a compressor 100 according to Embodiment 1. Fig. 2 is a cross-sectional
view schematically illustrating joining a suction connection pipe 12 and a joining
pipe 10 of the compressor 100 illustrated in Fig. 1. Figs. 3Ato 3D are schematic
5 diagrams illustrating the configuration of the joining pipe 10 and other
components and a first weld portion P. The configuration of the compressor 100 will be described with reference to Figs. 1, 2, and 3A to 3D. Note that Figs. 1, 2, and 3Ato 3D are longitudinal sectional view of various components. [0014]
10 [Description of Configuration]
As illustrated in Fig. 1, the compressor 100 includes a sealed container 1, an electric element 2, a compression element 3, and an accumulator 14 storing liquid refrigerant. The compressor 100 further includes the joining pipe 10 connected to the sealed container 1, the suction connection pipe 12 inserted in
15 the joining pipe 10, and a suction pipe 15 connecting the accumulator 14 and the
suction connection pipe 12.
As will be described below, the joining pipe 10 and the suction connection pipe 12 are joined by resistance welding. A weld portion (joining portion) between the joining pipe 10 and the suction connection pipe 12 corresponds to a
20 first weld portion P. Further, the sealed container 1 and the joining pipe 10 are
joined by, for example, resistance welding (projection welding). A weld portion between the sealed container 1 and the joining pipe 10 corresponds to a second weld portion. Further, the suction pipe 15 and the suction connection pipe 12 are joined by brazing or arc welding.
25 [0015]
(Sealed Container 1)
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The sealed container 1 accommodates the electric element 2 and the
compression element 3. The accumulator 14 is connected to the sealed
container 1 through various pipes. The sealed container 1 includes a body 1A
having a bottomed cylindrical shape, and an upper sheii 1B attached to an
5 opening formed at the top of the lower part of the container. The upper shell 1D
is press-fitted in the body 1Aand is connected thereto by arc welding. An
opening to which the suction connection pipe 12 and the joining pipe 10 are
attached is formed in the body 1Aof the sealed container 1. A discharge pipe 9
that discharges refrigerant compressed by the compression element 3 is
10 connected to the upper shell 1B.
[0016]
(Electric Element 2)
The electric element 2 includes, for example, a stator 2A fixed to an inner
circumferential surface of the sealed container 1, and a rotor 2B rotatably
15 disposed inside the stator 2A. A wire to conduct an electric current is wound
around the stator 2A. Further, a drive shaft 4 of the compressor element 3 (described below) is connected to the rotor 2B. [0017]
(Compression Element 3)
20 The compression element 3 includes a cylinder 5 having a space for
compressing refrigerant gas, the drive shaft 4 that transmits a driving force of the
electric element 2, an upper bearing 7 and a lower bearing 8 that support the
drive shaft 4, and a rolling piston 6 that is fitted around an eccentric part of the
drive shaft 4 and rotates in the cylinder 5.
25 One end of the suction connection pipe 12 is connected to the cylinder 5.
The refrigerant in the accumulator 14 is supplied to the cylinder 5. Then, since the rolling piston 6 is disposed in the cylinder 5, the refrigerant is compressed by
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the working of the rolling piston 6. The drive shaft 4 is connected at an upper
end side to the rotor 2B, and at a lower end side to the upper bearing 7 and the
lower bearing 8. The drive shaft 4 is used to transmit the driving force of the
electric element 2 to the rolling piston 6. The upper bearing 7 and the lower
G bearing 8 are disposed on an upper surface and a lower surface of the cylinder 5.
[0018]
(Accumulator 14)
The accumulator 14 is used to store liquid refrigerant and supply gaseous
refrigerant to the compression element 3. A refrigerant inlet pipe 14Ais
10 connected to the upper part of the accumulator 14. Further, the suction pipe 15
is connected to the lower part of the accumulator 14. [0019]
(Joining Pipe 10)
The joining pipe 10 is an iron member that is connected at one end to the
15 sealed container 1 and into which the suction connection pipe 12 is inserted. As
illustrated in Fig. 3A, the joining pipe 10 includes a reduced diameter portion
10A1 joined to the body 1A of the sealed container 1, a cylindrical portion 10A2
having a cylindrical shape formed to extend in the horizontal direction, and a
protruding portion 10A3 formed at the other end of the cylindrical portion 10A2.
20 Note that the protruding portion 10A3 corresponds to a second protruding
portion. [0020]
The reduced diameter portion 10A1 is formed such that the outer diameter
decreases from the joining pipe 10 side to the compression element 3 side.
25 That is, the reduced diameter portion 10A1 is formed such that the outer
diameter decreases from the other end side to the one end side of the joining pipe 10. The reduced diameter portion 10A1 is formed atone end of the
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cylindrical portion 10A2. The reduced diameter portion 10A1 is disposed at the
opening of the body 1A of the sealed container 1 and joined to a part of the
sealed container 1 where the opening is formed. The reduced diameter portion
10A1 and the body 1A are joined by, for example, resistance welding.
5 The cylindrical portion 10A2 is a member having a circular cross sectional
shape. The cylindrical portion 10A2 has one end on which the reduced diameter portion 10A1 is formed and has the other end on which the protruding portion 10A3 is formed. The suction connection pipe 12 is inserted in the cylindrical portion 10A2. That is, the inner circumferential surface of the
10 cylindrical portion 10A2 and the outer circumferential surface of the suction
connection pipe 12 (a straight pipe portion 12A2 of the suction connection pipe
12)are opposed to each other.
[0021]
The protruding portion 10A3 is formed on the other end of the cylindrical
15 portion 10A2, protrudes from the inner circumferential side to the outer
circumferential side, and is disposed at the compression element 3 side with respect to a protruding portion 12A3. Asecond electrode 21 (described below) is disposed between the protruding portion 10A3 and the outer circumferential surface of the sealed container 1. The protruding portion 10A3 includes an
20 inner diameter edge 10A4 formed on the inner circumferential surface at a
position where the protruding portion 10A3 is formed.
The inner diameter edge 10A4 is formed on the inner circumferential surface of the other end of the joining pipe 10. The inner diameter edge 10A4 is formed around the entire circumference of the inner circumferential surface of the
25 other end. The inner diameter edge 10A4 preferably has an edge shape of 90
degrees, but may have slight burrs or have a chamfered shape. The inner diameter edge 10A4 is joined while the protruding portion 12A3 is pressed
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thereagainst. That is, the protruding portion 12A3 includes a tapered surface
portion 12A4 corresponding to the inner diameter edge 10A4 such that the
tapered surface portion 12A4 and the inner diameter edge 10A4 are in contact
with each other. Thus, the suction connection pipe 12 is resistance welded
5 while being pressed against the sealed container 1 by the working of the first
electrode 20 (described below). [0022]
(Suction Connection Pipe 12)
The suction connection pipe 12 is an iron member having one end
10 connected to the compression element 3 and the other end connected to the
suction pipe 15. That is, the suction connection pipe 12 establishes communication between the compression element 3 and the suction pipe 15. The suction connection pipe 12 is joined to the suction pipe 15 in advance. It is preferable that the suction connection pipe 12 and the suction pipe 15 be
15 integrally joined by furnace brazing during manufacture of the accumulator 14.
However, the suction connection pipe 12 and the suction pipe 15 may be joined by gas brazing, arc welding, laser welding, or other methods in a separate process. It is preferable in terms of cost that the suction connection pipe 12 be formed by molding such as forging. However, the suction connection pipe 12
20 may be formed by cutting processing.
[0023]
As illustrated in Fig. 3B, the suction connection pipe 12 including a cylindrical portion 12AA having one end connected to the compression element 3 and having a cylindrical shape extending in the horizontal direction, and the
25 protruding portion 12A3 formed at the other end of the cylindrical portion 12AA.
Note that the protruding portion 12A3 corresponds to a first protruding portion. [0024]
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The cylindrical portion 12AA includes: a compression element connection
portion 12A1 inserted in the opening of the body 1A of the sealed container 1 and
connected to the compression element 3; and the straight pipe portion 12A2
having one end connected to the compression element connection portion 12A1
5 and the other end connected to the protruding portion 12A3, and facing the inner
circumferential surface of the joining pipe 10. The compression element connection portion 12A1 is formed to have an outer diameter smaller than that of the straight pipe portion 12A2. The straight pipe portion 12A2 is inserted in the joining pipe 10. That is, the joining pipe 10 has a function of guiding the suction
10 connection pipe 12 when connecting the suction connection pipe 12 to the
compression element 3. [0025]
The protruding portion 12A3 is an annular member formed on the other end of the suction connection pipe 12 and protruding from the inner
15 circumferentiai side to the outer circumferential side. The tapered surface
portion 12A4 is formed on the protruding portion 12A3. The tapered surface portion 12A4 is formed such that the outer diameter increases from the compression element 3 side to the joining pipe 10 side. That is, the tapered surface portion 12A4 is formed such that the outer diameter increases from one
20 end side to the other end side of the suction connection pipe 12. Further, the
protruding portion 12A3 includes the tapered surface portion 12A4 formed on the surface at the sealed container 1 side, a tapered surface portion 12A5 formed on the inner circumferential surface at a position where the protruding portion 12A3 is formed, and a flat surface portion 12A6 formed at the side opposite the tapered
25 surface portion 12A4.
[0026]
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The tapered surface portion 12A4 is disposed to be in contact with the
inner diameter edge 10A4 of the joining pipe 10. The tapered surface portion
12A5 is a portion serving as an inlet through which the suction pipe 15 is
inserted. The tapered surface portion 12A5 is formed such that the inner
5 diameter increases from the sealed container 1 side to the suction connection
pipe 12 side. That is, the tapered surface portion 12A5 is formed such that the inner diameter increases from one end side to the other end side of the suction connection pipe 12. Since the tapered surface portion 12A5 is formed, the suction pipe 15 is easily inserted into a pipe insertion portion 12A7 of the suction
10 connection pipe 12. The flat surface portion 12A6 includes a flat surface
perpendicular to the longitudinal direction of the suction connection pipe 12. The first electrode 20 used for resistance welding (described below) is disposed on the flat surface portion 12A6. [0027]
15 (Suction Pipe 15)
The suction pipe 15 has one end connected to the suction connection pipe 12 and the other end connected to the accumulator 14. The material used for the suction pipe 15 depends on the method for connecting to the suction connection pipe 12. For example, in the case of joining the suction pipe 15 and
20 the suction connection pipe 12 by arc welding or laser welding, the suction pipe
15 needs to be made of iron. On the other hand, in the case of joining by integral brazing or gas brazing, the suction pipe 15 may be made of iron or may be made of copper. [0028]
25 (First Weld portion P)
As illustrated in Fig. 3D, the first weld portion P is formed on a contact surface between the protruding portion 12A3 and the protruding portion 10A3.
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That is, the first weld portion P is formed on a contact surface between the
tapered surface portion 12A4 and the inner diameter edge 10A4. Then, the first
weld portion P is formed such that the diameter increases toward its other end.
The first weld portion P is formed by resistance welding the suction connection
5 pipe 12 and the joining pipe 10.
[0029]
[Description of Operations]
The following describes operations. When the drive shaft 4 is rotated by
the electric element 2, the rolling piston 6 eccentrically rotates in the cylinder 5.
10 Then, refrigerant flows from the accumulator 14 into the cylinder 5 through the
suction connection pipe 12, and the refrigerant is compressed. The
compressed refrigerant is once emitted into the sealed container 1, and then is
discharged from the discharge pipe 9 to a condenser and other devices (not
illustrated) through the clearances in the electric element 2. The refrigerant
15 having passed through the condenser, an expansion device, an evaporator, and
other devices returns again to the accumulator 14. This cycle is repeated. [0030]
[Manufacturing Method]
Fig. 4 is a horizontal sectional view schematically illustrating the
20 configuration of electrodes (the first electrode 20 and the second electrode 21)
for resistance welding for joining the suction connection pipe 12 and the joining
pipe 10 illustrated in Fig. 2. Fig. 5Ais a view schematically illustrating the
configuration of the second electrode 21 for resistance welding illustrated in Fig.
4. Fig. 5B is a perspective view schematically illustrating the configuration of
25 the first electrode 20 for resistance welding illustrated in Fig. 4. Fig. 5C is a side
view schematically illustrating the configuration of the first electrode 20 for resistance welding illustrated in Fig. 4. Fig. 5D is a flowchart of manufacture of
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the compressor 100. The method for manufacturing the compressor 100 will be
described with reference to Figs. 4 and 5Ato 5D.
[0031]
As illustrated in Fig. 5D, for connecting the joining pipe 10, the suction
5 connection pipe 12, and the suction pipe 15 of the compressor 100, the following
steps are performed. More specifically, the method for manufacturing the
compressor 100 includes a joining pipe connecting step, a suction pipe
connecting step, a suction connection pipe connecting step, an electrode
disposing step, and a resistance welding step.
10 [0032]
(Joining pipe Connecting Step)
In the joining pipe connecting step, one end of the joining pipe 10 made of
iron is connected to the body 1Aof the sealed container 1. More specifically, the
joining pipe 10 and the body 1Aare resistance welded. Note that the resistance
15 welding in this step is performed under a condition where the compression
element 3 and the electric element 2 are not disposed in the sealed container 1.
Therefore, resistance welding can be performed while a member that holds the
inner circumferential side of the body 1A of the sealed container 1 is disposed.
Therefore, even when the joining pipe 10 is pressed against the body 1A of the
20 sealed container 1 to perform resistance welding, it is possible to suppress the
occurrence of distortion of the sealed container 1. The compression element 3
and other components are installed in the sealed container 1 after the joining
pipe connection step is performed but before the subsequent suction connection
pipe connecting step.
25 [0033]
(Suction Pipe Connecting Step)
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In the suction pipe connecting step, one end of the suction pipe 15 is
connected to the other end of the suction connection pipe 12. The suction pipe
connecting step is a step of connecting the suction pipe 15 and the suction
connection pipe 12 in advance, before the subsequent suction connection pipe
5 connecting step. In the suction pipe connecting step, joining is performed by, for
example, furnace brazing, gas brazing, arc welding, and laser welding. [0034]
(Suction Connection Pipe Connecting Step)
In the suction connection pipe connecting step, the suction connection
10 pipe 12 made of iron is inserted into the joining pipe 10, and one end of the
suction connection pipe 12 is connected to the compression element 3 in the sealed container 1. [0035]
(Electrode Disposing Step)
15 In an electrode disposing step, the first electrode 20 is disposed on the
suction connection pipe 12, and the second electrode 21 is disposed on the back
surface of the protruding portion 10A3 of the joining pipe 10. That is, the
electrode disposing step is a step of disposing the first electrode 20 on the
protruding portion 12A3 formed in advance on the other end of the suction
20 connection pipe 12, and disposing the second electrode 21 such that the second
electrode 21 is interposed between the protruding portion 10A3, which is formed
in advance on the other end of the joining pipe 10 and located at the sealed
container 1 side with respect to a first protruding portion 12A, and the sealed
container 1. The first electrode 20 is disposed on the flat surface portion 12A6.
25 Note that the first electrode 20 and the second electrode 21 are electrodes used
for resistance welding, and are connected to a power supply (not illustrated) for resistance welding.
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[0036]
In the electrode disposing step, the first electrode 20 and the second
electrode 21 are disposed such that the first electrode 20 is located at the upper
side of the second electrode 21. That is, the sealed container 1 is located at the
5 lower side, and the suction connection pipe 12 is located at the upper side.
[0037]
The first electrode 20 is disposed on the flat surface portion 12A6 of the suction connection pipe 12, and presses the flat surface portion 12A6 in the downward direction such that the suction connection pipe 12 is pressed against
10 the joining pipe 10.
The second electrode 21 is disposed on the back surface (the surface at the sealed container 1 side) of the joining pipe 10 (the protruding portion 10A3). That is, the second electrode 21 is disposed to be inserted at the lower side of the protruding portion 10A3 of the joining pipe 10. Thus, the second electrode
15 21 is interposed between the protruding portion 10A3 and the sealed container 1.
[0038]
Accordingly, when the first electrode 20 is pressed downward, the suction connection pipe 12 is pressed against the joining pipe 10. Therefore, even when the first electrode 20 presses the suction connection pipe 12 in the
20 downward direction, the joining pipe 10 can be inhibited from pushed into the
sealed container 1, by the working of the second electrode 21. Thus, it is possible to suppress distortion of the sealed container 1 and the compression element 3. That is, the second electrode 21 receives a pressing force of the suction connection pipe 12 that pushes the joining pipe 10 into the sealed
25 container 1, and holds the joining pipe 10 such that a load is not applied to the
sealed container 1. [0039]
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(Resistance Welding Step)
The resistance welding step (projection welding step) is a step of applying
an electric current to the first electrode 20 and the second electrode 21 to
resistance weld the joining pipe 10 and the suction connection pipe 12. By
5 performing the resistance welding step, a contact portion between the joining
pipe 10 and the suction connection pipe 12 is heated by an electric current
applied thereto, so that joining is accomplished. By passing an electric current
of a predetermined magnitude between the first electrode 20 and the second
electrode 21 for a predetermined period of time, the contact surfaces of the
10 suction connection pipe 12 and the joining pipe 10 are joined.
[0040]
[First Electrode 20 and Second Electrode 21]
The following describes the configuration of the first electrode 20 and the
second electrode 21. The first electrode 20 and the second electrode 21 used
15 for manufacture of compressor 100 will be described with reference to Figs. 4
and 5Ato 5C. [0041]
As illustrated in Fig. 5A, to stably join the suction connection pipe 12 and
the joining pipe 10 throughout the circumference, the second electrode 21 is
20 formed to be split into right and left (or front and rear) parts. In the second
electrode 21, an opening 21A into which the joining pipe 10 and the suction
connection pipe 12 are inserted is formed. Further, in the second electrode 21,
a recessed portion 21B resembling a cut-out that fits the back surface of the
joining pipe 10 is formed, and a tongue-and-groove joint 22 is formed such that
25 no difference in level is produced between the right and left parts of the second
electrode 21. The recessed portion 21B is an annular recess and the protruding
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portion 10A3 Is disposed therein. The opening 21Ais formed at the center of
the recessed portion 21B.
[0042]
If the sealed container 1 and the surface of the second electrode 21 come
5 into contact, an electric current is applied thereto, so that undesired portions
(portions different from the portions to be joined) might be joined. In view of this, an insulating material 23 is provided on the sealed-container-1-side surface of the second electrode 21. [0043]
10 Further, in the first electrode 20 and the second electrode 21, the
electrodes may be made of a normal copper material or a copper alloy material with an enhanced strength. In the case where the interval between the protruding portion 10A3 of the joining pipe 10 and the sealed container 1 is small, if the strength of the second electrode 21 is insufficient, the second electrode 21
15 is deformed when the first electrode 20 is pressed against the joining pipe 10.
Then, a pressing force is also applied to the sealed container 1, so that the sealed container 1 and the cylinder 5 might be distorted. In view of this, it is preferable that in the second electrode 21, a portion to be in contact with the joining pipe 10 be made of copper or a copper alloy and a portion at the sealed
20 container 1 side be made of an iron-based non-magnetic material such that the
strength is ensured. [0044]
As illustrated in Figs. 5B and 5C, similar to the second electrode 21, the first electrode 20 is also formed to be split into right and left parts. The first
25 electrode 20 includes a hollow portion 20A in which the suction pipe 15 is
disposed, and openings 20A1 formed on one end and the other end of the hollow portion 20A. Further, the first electrode 20 includes a planar surface portion 20B
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that is placed in contact with the flat surface portion 12A6 of the suction
connection pipe 12. Since the first electrode 20 and the suction connection pipe
12 are configured such that the surfaces of the flat surface portion 12A6 and the
planar surface portion 20B match, the pressing force of the first electrode 20 is
5 effictentjy transmitted tuward the suction connection pipe 12. Thus, it is possible
to more reliably perform resistance welding. [0045]
[Advantageous Effects of Compressor 100 according to Embodiment 1] The compressor 100 according to Embodiment 1 includes the first weld
10 portion P formed by joining, by resistance welding, the suction connection pipe
12 that is made of iron and that connects the suction pipe 15 at the accumulator 14 side and the compressor element 3, and the joining pipe 10 that is made of iron and connected to the sealed container 1 and into which the suction connection pipe 12 is inserted,. That is, the suction connection pipe 12 and the
15 joining pipe 10 are not joined by brazing. Thus, there is no need to use
materials, such as copper, that are more expensive than iron, and hence it is
possible to reduce an increase in manufacturing cost.
[0046]
According to the compressor 100 of Embodiment 1, the suction connection
20 pipe 12 is resistance welded, not by being pressed directly against the sealed
container 1, but by being pressed against the joining pipe 10. That is, when the suction connection pipe 12 is pressed toward the sealed container 1, the pressing force is inhibited from being applied directly to the sealed container 1 and the compression element 3, due to the presence of the joining pipe 10.
25 Further, the compressor 100 according to Embodiment 1 includes the
joining pipe 10. Thus, when performing resistance welding, it is possible to perform resistance welding by pressing the suction connection pipe 12 toward
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the sealed container 1 while holding the joining pipe 10. Therefore, when the
suction connection pipe 12 is pressed toward the sealed container 1, the
pressing force is inhibited from being applied to the sealed container 1 and the
compression element 3.
5 Thus, Since the compressor 100 according to Embodiment 1 has a
configuration capable of suppressing the occurrence of distortion of the sealed container 1 and the compression element 3 when resistance joining is performed, it is possible to suppress a reduction in reliability. [0047]
10 According to the compressor 100 of Embodiment 1, it is possible to
suppress the occurrence of distortion of the compression element 3. Therefore, it is possible to suppress an increase in wear of various members of the compression element 3 due to the distortion, and to suppress a reduction in reliability.
15 [0048]
According to the compressor 100 of Embodiment 1, since the joining pipe 10 and the suction connection pipe 12 are joined by resistance welding, it is possible to suppress the occurrence of scattering of gas, noise, and so on, and to inhibit degradation of the work environment. Note that compared to resistance
20 welding, brazing is more likely to cause scattering of gas, noise, and so on.
[0049]
In brazing, it is necessary to apply heat to a weld portion of a pipe until a brazing material can penetrate into the weld portion. Therefore, heat is also transferred to the compression element 3 (such as the cylinder 5) connected to
25 the suction connection pipe 12, which might cause distortion of the compression
element 3. Further, in brazing, heat is often applied to the side surface of the sealed container 1, in addition to the weld portion. The heat applied to the side
21

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surface of the sealed container 1 might cause distortion of the sealed container
1. On the other hand, according to the compressor 100 of Embodiment 1, since
the joining pipe 10 and the suction connection pipe 12 are joined by resistance
welding, it is possible to suppress the occurrence of distortion of the compression
5 element 3 due to heat, and to suppress a reduction in reliability.
[0050]
Fig. 10 is a diagram illustrating a conventional example 1. In the conventional example 1, copper plating is applied to a suction connection pipe 12 to perform joining by brazing. Then, the suction connection pipe 12 and a
10 copper pipe 10a for guiding that is connected to a joining pipe 10 are brazed.
Thus, since a copper material is needed, the manufacturing cost is increased. Further, problems such as a reduction in performance due to distortion of a cylinder 5 caused by brazing, and problems such as degradation of the work environment might occur. On the other hand, in Embodiment 1, since the
15 suction connection pipe 12 and the joining pipe 10 are joined by resistance
welding, these problems can be solved. [0051]
Fig. 11 is a diagram illustrating a conventional example 2. In the conventional example 2, a bulging portion 15A having a flat portion is formed by
20 performing bulging processing on a suction pipe 15 serving also as a suction
connection pipe. Further, a body raised portion 1AA is formed by being raised on the outer side of the sealed container 1 by burring processing. Then, the bulging portion 15Aand the body raised portion 1AAof the sealed container 1 are welded. With this method, a sealed container 1 directly receives a pressing
25 force applied for resistance welding, resulting in not only deformation of the
sealed container 1 but also deformation of a cylinder 5 at the compression element 3 side. This might cause a reduction in the performance of the
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compressor, which might reduce the reliability. On the other hand, in
Embodiment 1, the joining pipe 10 is added such that a load is received by the
joining pipe 10, thereby preventing deformation of the cylinder 5. Thus, it is
possible to suppress a reduction in the reliability of the compressor 100.
5 [0052]
Further, in the configuration of Fig. 11, a structure corresponding to the joining pipe 10 is not provided, so that the bulging portion 15Aand the sealed container 1 are in direct contact with each other. Therefore, it is difficult to hold a member (the bulging portion 15A) under pressure so as not to be pushed in.
10 On the other hand, the compressor 100 according to Embodiment 1 includes the
joining pipe 10, and therefore it is easy to hold a member that is pushed in during resistance welding. [0053]
In Embodiment 1, the suction connection pipe 12 and the joining pipe 10
15 are joined by resistance welding. However, the joining method is not limited
thereto. Other joining methods than resistance welding may be used as long as the suction connection pipe 12 made of iron and the joining pipe 10 made of iron can be joined. [0054]
20 [Modification of Embodiment 1]
Fig. 6 is a schematic diagram illustrating a modification of the joining pipe 10 of the compressor 100 according to Embodiment 1 of the present invention, wherein an electrode receiving portion is formed in a tapered shape. Fig. 6 is a horizontal sectional view illustrating the joining pipe 10 and other components.
25 As illustrated in Fig. 6, the joining pipe 10 includes a cylindrical portion 10B2
formed such that the outer diameter increases from one end side to the other end side. The outer circumferential surface of the cylindrical portion 10B2 is the
23

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electrode receiving portion. In the configuration of Fig. 6, since a force of
separating the second electrode 21, which is split into right and left parts, to the
right and the left, it is necessary to add a mechanism to hold the second
electrode 21. However, since the load in the vertical direction is reduced, there
5 is an advantageous effect that the life of the second electrode 21 is extended.
Further, there is also provided an effect of facilitating molding of the joining pipe 10 by forging. [0055] Embodiment 2
10 Fig. 7 is a cross-sectional view schematically illustrating joining a suction
connection pipe 120 and a joining pipe 110 of a compressor 100 according to Embodiment 2 of the present invention. Fig. 8A is a schematic diagram illustrating the configuration of the joining pipe 110. Fig. 8B is a schematic diagram illustrating the configuration of the suction connection pipe 120. The
15 compressor 100 according to Embodiment 2 will be described with reference to
Figs. 7, 8A, and 8B. Note that in Embodiment 2, elements common to Embodiment 1 are denoted by the same reference signs, and the differences will be mainly described. [0056]
20 In Embodiment 1, the first weld portion P is formed on the contact surface
between the inner diameter edge 10A4 of the joining pipe 10 and the tapered surface portion 12A4 of the suction connection pipe 12. On the other hand, in Embodiment 2, instead of forming the inner diameter edge 10A4 in the joining pipe 110, a right angle is formed in cross section parallel to the longitudinal
25 direction of the joining pipe 10. Then, on the joining pipe 110, a projection
110A4 is formed at a position where a protruding portion 10A3 is formed. Further, in Embodiment 2, a protruding portion 120A3 not having the tapered
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surface portion 12A4 is formed in piace of the protruding portion 12A3 of the
suction connection pipe 120.
[0057]
The joining pipe 10 includes the protruding portion 10A3 formed on the
5 other end, protruding from the inner circumferential side to the uuter
circumferential side, and disposed at the compression element 3 side with respect to the protruding portion 120A3. Further, the protruding portion 10A3 includes a projection 110A4 formed to be opposed to the protruding portion 120A3 and projecting toward the protruding portion 120A3. The projection
10 110A4 is formed in an annular shape to extend along the opposed surfaces of
the protruding portion 10A3 and the protruding portion 120A3. Note that the projection 110A4 corresponds to a first projection. [0058]
The suction connection pipe 12 includes the annular protruding portion
15 120A3 formed on the other end and protruding from the inner circumferential side
to the outer circumferential side. The protruding portion 120A3 and the protruding portion 10A3 are opposed to each other. Further, the protruding portion 120A3 is formed to be parallel to the opposed surface of the protruding portion 10A3. That is, the surface of the protruding portion 120A3 at the
20 protruding portion 10A3 side is parallel to the vertical direction.
[0059]
Although not illustrated, a first weld portion P is formed on a contact surface between the protruding portion 120A3 and the projection 110A4. [0060]
25 [Advantageous Effects of Compressor 100 according to Embodiment 2]
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In addition to the same advantageous effects as those provided by the
compressor 100 according to Embodiment 1, the compressor 100 according to
Embodiment 2 provides the following advantageous effects.
[0061]
5 According to the uumpiessor 100 of Embodiment 2, the joining pipe 110
includes the projection 110A4. Therefore, even if the axis of the suction connection pipe 120 and the axis of the joining pipe 110 are not aligned when the suction connection pipe 120 is inserted into the cylinder 5, the contact surface between the protruding portion 120A3 and the protruding portion 10A3 is stable,
10 making it possible to increase the joining quality.
[0062]
[Modification of Embodiment 2]
Fig. 9 is a schematic diagram illustrating a modification of the joining pipe 110 of the compressor 100 according to Embodiment 2 of the present invention,
15 wherein a projection is formed on the suction connection pipe 120. As
illustrated in Fig. 9, instead of forming the projection 110A4 on the joining pipe 110, a projection 120A4 may be formed on the suction connection pipe 120. That is, the protruding portion 120A3 includes the projection 120A4 formed on a surface thereof facing the protruding portion 10A3, and projecting toward the
20 protruding portion 10A3. The projection 120A4 is formed in an annular shape to
extend along the opposed surfaces of the protruding portion 10A3 and the protruding portion 120A3. Note that the projection 120A4 corresponds to a first projection. [0063]
25 Note that Embodiment 2 and the modification of Embodiment 2 may be
combined such that both the projections are formed. That is, a configuration is
26

637080 KPO-2531
possible in which the projection 110A4 is formed on the joining pipe 110 and the
projection 120A4 is formed on the suction connection pipe 120.
[0064]
Further, the suction connection pipe 120 is usually press-fitted into an
5 insertion portion of the cylinder 5. An insulating seal material may be provided
in a contact position between a compression element connection portion 12A1 of the suction connection pipe 120 and the cylinder 5. Thus, it is possible to suppress distortion of the cylinder 5 due to press-fitting of the suction connection pipe 120. Further, since the welding current concentrates in an area between
10 the suction connection pipe 120 and the joining pipe 110 without being shunted, it
is possible to stably perform resistance welding. Reference Signs List [0065]
1 sealed container 1A body 1AA body raised portion 1B upper
15 shell 2 electric element 2A stator 2B rotor 3 compression element
4 drive shaft 5 cylinder 6 rolling piston 7 upper bearing 8 lower bearing 9 discharge pipe 10a copper pipe 10 joining pipe 10A1 reduced diameter portion 10A2 cylindrical portion 10A3 protruding portion 10A4 inner diameter edge 10B2 cylindrical portion 12 suction connection
20 pipe 12A first protruding portion 12A1 compression element connection
portion 12A2 straight pipe portion 12A3 protruding portion 12A4 tapered surface portion 12A5 tapered surface portion 12A6 flat surface portion 12A7 suction pipe insertion portion 12AA cylindrical portion 14 accumulator 14A refrigerant inlet pipe 15 suction pipe 15A bulging
25 portion 20 first electrode 20A hollow portion 20A1 opening 20B
pianar surface portion 21 second electrode 21A opening 21B recessed portion 22 tongue-and-groove joint 23 insulating material 100
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compressor 110 joining pipe 110A4 projection 120 suction connection pipe 120A3 protruding portion 120A4 projection P first weld portion
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637080 KPO-2531
CLAIMS [Claim 1]
A compressor comprising:
a sealed container;
5 a compression element disposed in the sealed container and configured to
compress refrigerant;
an electric motor element disposed in the sealed container and configured to drive the compression element;
a joining pipe made of iron, the joining pipe having one end connected to
10 the sealed container;
a suction connection pipe made of iron, the suction connection pipe being inserted in the joining pipe and having one end connected to the compression element; and
a suction pipe having one end connected to an other end of the suction
15 connection pipe,
the suction connection pipe including an annular first protruding portion formed on the other end thereof and protruding from an inner circumferential side to an outer circumferential side,
the first protruding portion of the suction connection pipe and an other end
20 of the joining pipe being joined to one another.
[Claim 2]
The compressor of claim 1, further comprising a first weld portion formed
by resistance welding the first protruding portion of the suction connection pipe
and the other end of the joining pipe.
25 [Claim 3]
The compressor of claim 2, wherein the first protruding portion includes a tapered surface portion forming an increasing outer diameter of the suction
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637080 KPO-2531
connection pipe increasing from one end side to an other end side of the suction connection pipe,
the joining pipe including an annular inner diameter edge on an inner
circumferential surface of the other end thereof,
5 the tapered surface portion being pressed agsinst the inner diameter edge,
and
the first weld portion being formed at least on a contact surface between
the inner diameter edge and the tapered surface portion.
[Claim 4]
10 The compressor of any one of claims 1 to 3, wherein the joining pipe is
formed to have an outer diameter increasing from one end side to an other end side of the joining pipe. [Claim 5]
The compressor of claim 2, wherein
15 the joining pipe includes a second protruding portion being formed on the
other end thereof, protruding from an inner circumferential side to an outer circumferential side, and disposed at a compression element side with respect to the first protruding portion,
the first protruding portion and the second protruding portion are opposed
20 to each other, and
the first weld portion is formed at least on opposed surfaces of the first protruding portion and the second protruding portion. [Claim 6]
The compressor of claim 5, wherein the first protruding portion includes a
25 first projection formed on a surface thereof facing the second protruding portion,
and projecting toward the second protruding portion. [Claim 7]
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637080 KPO-2531
The compressor of claim 6, wherein the first projection is formed in an
annular shape to extend along the opposed surfaces of the first protruding
portion and the second protruding portion.
[Claim 8]
5 The compressor of any one of claims 5 to 7, wherein the second
protruding portion includes a second projection formed on a surface thereof
facing the first protruding portion, and projecting toward the first protruding
portion.
[Claim 9]
10 The compressor of claim 8, wherein the second projection is formed in an
annular shape to extend along the opposed surfaces of the first protruding portion and the second protruding portion. [Claim 10]
The compressor of any one of claims 1 to 9, further comprising a second
15 weld portion formed by joining the sealed container and the joining pipe by
resistance welding. [Claim 11]
A method for manufacturing a compressor that comprises
a sealed container,
20 a compression element disposed in the sealed container and configured to
compress refrigerant, and
an electric motor element disposed in the sealed container and configured to drive the compression element, the method comprising:
a joining pipe connecting step of connecting one end of a joining pipe
25 made of iron to the sealed container;
a suction connection pipe connecting step of inserting a suction connection pipe made of iron into the joining pipe, and connecting one end of the suction connection pipe to the compression element;
an electrode disposing step of disposing a first electrode on an other end
5 of the suction connection pipe, and disposing a second electrode on the joining
pipe, and
a resistance welding step of applying an electric current to the first
electrode and the second electrode to resistance weld the joining pipe and the
suction connection pipe.
10 [Claim 12]
The method for manufacturing a compressor of claim 11, wherein in the
electrode disposing step, the first electrode and the second electrode are
disposed on the suction connection pipe and the joining pipe such that the first
electrode is located at an upper side of the second electrode, and
15 in the resistance welding step,
the first electrode is pressed against the first protruding portion, and
the resistance welding is performed while holding the second electrode to
prevent the suction connection pipe and the joining pipe from being moved
toward the compression element when the first electrode is pressed against the
20 first protruding portion.
32