JPH08200213A - Linear compressor - Google Patents

Abstract

PURPOSE: To provide a linear compressor capable of improving its durability and reliability by supplying sufficient oil on a piston part where the piston slides on the cylinder. CONSTITUTION: An electrically-operated element 3 and a compressor element 4 are stored inside a closed container 2 and the compressor element 4 is composed of a cylinder 11 and piston 12 which is fitted to a trembler 7 of the electrically-operated element 2 and makes a reciprocating motion. It is provided with a piston part 12A, which is formed on one of the ends of the piston 12 and loosely inserted inside the cylinder 11 so that it can freely make a reciprocating motion, a sub-bearing 36, which is provided in the position opposite to the cylinder 11 and holds the other end of the piston 12 so that it can freely make a reciprocating motion, an oil suction hole 37, which is drilled in the sub-bearing 36, an oil outflow hole 46, which is drilled in the piston part 12A of the piston 12, and an oil pump 38 provided on the other end inside the piston 12. The oil pump 38 is provided with a small hole 41 communicating with the oil outflow hole 46, an opening 42 opened inside the sub-bearing 36, and a blowout passage 43, which gradually narrows towards the small hole 41 from the opening 42.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a linear compressor used for air conditioning and freezing, for example.

[0002]

2. Description of the Related Art A conventional linear (vibration type) compressor of this type is disclosed, for example, in Japanese Utility Model Publication No. 57-26061 (F04).
B35 / 04), a movable body (vibrator) composed of an electromagnet (driving coil) is provided in the magnetic field of a stator composed of a permanent magnet, and a piston and a spring are attached to this movable body, and the movable body is alternately arranged. The attraction / repulsion between the permanent magnet and the electromagnet caused by passing an electric current and the compression / expansion of the spring cause the piston to reciprocate in the cylinder,
Compressing the refrigerant.

Further, for example, as disclosed in Japanese Utility Model Publication No. 63-2628 (F04B35 / 04), there has been one in which the stator side is an electromagnet and the movable body side is a permanent magnet.

[0004]

By the way, since friction is generated between the cylinder and the cylinder that reciprocate in the cylinder, it is necessary to supply oil for lubrication. The oil was simply sprinkled on the sliding part between the cylinder and the piston with the blades, and lubrication was performed only by the atmosphere of the oil mist in which the oil was mixed in the refrigerant.Therefore, sufficient oil could be supplied to the sliding part. However, there was a problem with durability and reliability.

The present invention has been made to solve the above-mentioned conventional technical problems, and sufficiently supplies oil to a piston portion where a cylinder and a piston slide to improve durability and reliability. It is an object to provide a linear compressor that can perform.

[0006]

A linear compressor according to a first aspect of the present invention stores an electric element and a compression element in a closed container, and the compression element is attached to a cylinder and a vibrator of the electric element. It is composed of a reciprocating piston, and is formed at one end of the piston and is freely inserted into the cylinder so as to reciprocate, and is provided at a position facing the cylinder and reciprocates at the other end of the piston. It is provided with a sub bearing which is movably held, an oil suction hole formed in the sub bearing, an oil outflow hole formed in the piston portion of the piston, and an oil pump provided at the other end in the piston. The oil pump is provided with a small hole communicating with the oil outflow hole, an opening opened in the sub bearing, and an outlet passage gradually narrowed from this opening toward the small hole.

According to the linear compressor of the invention of claim 2,
An electric element and a compression element are housed in a closed container, and the compression element is composed of a cylinder and a piston attached to a vibrator of the electric element to reciprocate, and formed at one end of the piston. , A reciprocatingly loosely inserted piston in the cylinder, a sub-bearing provided at a position facing the cylinder and reciprocally holding the other end of the piston, and an oil suction hole formed in the sub-bearing And an oil outflow hole formed in the piston portion of the piston, and an oil pump provided at the other end inside the piston. The oil pump has an opening that communicates the oil outflow hole with the inside of the auxiliary bearing. , A valve element that closes this opening from the inside of the piston,
And a spring member that constantly presses the valve element against the opening.

According to the linear compressor of the invention of claim 3,
An electric element and a compression element are housed in a closed container, and the compression element is composed of a cylinder and a piston attached to a vibrator of the electric element to reciprocate, and formed at one end of the piston. A piston portion reciprocally inserted into the cylinder, an oil outlet hole formed in the piston portion, and an oil pump provided at the other end of the piston for supplying oil to the oil outlet hole And
A groove that is continuous with the oil outflow hole is formed on the outer surface of the piston portion.

[0009]

According to the linear compressor of the first aspect of the invention, when the piston moves to the cylinder side, oil is sucked into the sub bearing through the oil suction hole, and when the piston moves to the sub bearing side, the suction is performed. The oil thus collected flows into the oil pump through the opening. The oil that has flowed into the oil pump is compressed in the process of passing through the blowout passage, is blown out from the small hole, and reaches the oil outflow hole of the piston portion. As a result, the sliding part between the cylinder and piston is smooth,
In addition, it is sufficiently lubricated to improve durability and reliability.

According to the linear compressor of the second aspect of the present invention, when the piston moves to the cylinder side, oil is sucked into the sub bearing through the oil suction hole, and when the piston moves to the sub bearing side, The valve body opens the opening of the oil pump against the spring member. by this,
The oil sucked into the sub bearing flows in through the opening and eventually reaches the oil outflow hole in the piston part, so the sliding part between the cylinder and piston is smooth and sufficiently lubricated, and durability and reliability are improved. improves.

According to the linear compressor of the third aspect of the present invention, since the groove of the piston which is continuous with the oil outflow hole is formed in the piston portion, the oil supplied from the oil pump and outflowed from the oil outflow hole is transferred to the cylinder and the piston. It will spread smoothly over the entire sliding area between and. As a result, the storage portion is sufficiently lubricated, and durability and reliability can be improved.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows a vertical side view of a linear compressor 1 of the present invention. An electric element 3 and a compression element 4 are housed in a closed container 2 of the linear compressor 1, and the electric element 3 includes a stator 6, a vibrator 7 disposed inside the stator 6, and a spring member 8. The cylinder 11 is composed of 9 and the like, and the compression element 4 serves as a motor case to which the stator 6 is attached.
In addition, a piston 12 and the like in which a piston portion 12A at the upper end is freely reciprocally moved (vertical movement) are configured in a cylinder portion 11A of the cylinder 11.

A suction valve and a discharge valve (not shown) are attached to the upper end of the cylinder portion 11A of the cylinder 11, and a suction muffler 13 and a discharge muffler 14 are attached to the upper portion of the cylinder 11 so as to communicate with the respective valves.

The stator 6 includes a stator core 17 composed of a plurality of electromagnetic steel plates 16 ... Stacked in the moving direction of the piston 12 (vertical direction), and a plurality of stator iron cores 16 on the inner peripheral part of each electromagnetic steel plate 16. The coil 19 is wound in the formed groove with a groove insulating paper interposed therebetween. In this case, when a current is applied to the coil 19, the stator 6 is attached to the electromagnetic steel plate 1 in a horizontal plane.
A magnetic flux passing through the center of 6 is generated, and the direction of the magnetic flux is also reversed depending on the direction of the current.

Next, semi-circular arc-shaped permanent magnets 26 to 29 are provided in the vibrator 7, and the piston 12 is fixed inside the vibrator 7. Also, the piston 12
Is inserted concentrically with the center of the electromagnetic steel plate 16 of the stator 6, whereby the magnetic flux of the stator 6 horizontally crosses the vibrator 7 including the piston 12,
Actually, it occurs in a plane (horizontal plane) orthogonal to the moving direction (vertical direction) of the piston 12.

The permanent magnets 26 and 27 are provided on the upper portion of the vibrator 7, and the permanent magnets 28 and 29 are provided on the lower portion, whereby the permanent magnets 26 and 28, 27 and 29 are moved in the moving direction of the piston 12 (vertical direction). And the permanent magnet 26.
, 27, 28 and 29 are arranged in parallel in the direction of the magnetic flux that crosses the vibrator 7. Further, the permanent magnets 26 and 27 have opposite poles facing each other, and the permanent magnets 28 and 29 also have opposite poles facing each other. Further, the permanent magnets 26 and 28 and the permanent magnets 27 and 29 have different polarities.

A frame 34 is attached to the lower end of the stator 6, and an upward sub-bearing 36 is attached to the upper surface of the frame 34 so as to face below the cylinder portion 11A. The lower portion of the piston 36 is supported in the sub bearing 36 so as to be vertically movable, and the side surface of the sub bearing 36 is provided with oil suction holes 37, 37. In addition, an auxiliary bearing 36 is provided in the lower portion of the closed container 2.
Is filled with oil all around.

Here, the piston 36 has an inner hollow cylindrical shape with its upper end closed and its lower end opened, and an oil pump 38 is attached to its inner lower end.
This oil pump 38 has a small hole 4 on the upper surface as shown in FIG.
1 and an opening 42 on the lower surface, and an outlet passage 43 that is gradually narrowed by drawing a parabola from the opening 42 toward the small hole 41, and the opening 42 is open in the sub bearing 36.
The outlet passage 43 may have a linear inclined surface (tapered shape) as shown in FIG.

Further, an oil outlet hole 46 is formed in the piston portion of the piston 36 so as to correspond to a sliding portion of the cylinder 11 with the cylinder portion 11A.
Communicates with the small hole 41 of the oil pump 38 via the inside of the piston 36.

Further, the spring members 8 and 9 are coil springs, the spring member 8 is interposed between the cylinder 11 and the upper surface of the vibrator 7, and the spring member 9 is interposed between the frame 34 and the lower surface of the vibrator 7. It is provided and holds the vibrator 7 in the vertical center of the stator 6, that is, the center of the reciprocating motion of the piston 12, in a non-energized state. This facilitates the operation of the piston 12. The spring members 8 and 9 may be so-called Oxford leaf springs.

With the above structure, when an alternating current is passed through the coil 19, a magnetic flux is generated across the vibrator 7 in a plane orthogonal to the moving direction of the piston 12. The oscillator 7 extends the spring member 8 and compresses the spring member 9 so that the permanent magnets 26 and 27, through which the magnetic flux easily passes, face the stator 6, and move downward. Then, if the direction of the electric current is reversed, the permanent magnets 28, 29 move upward so as to face the stator 6 conversely, so that the piston 12 reciprocally vibrates (moves up and down) in the cylinder portion 11A. It will be.
By the reciprocating movement of the piston 12, the refrigerant is sucked from the suction valve through the suction muffler 13, compressed, and discharged from the discharge valve to the discharge muffler 14.

Here, the piston 12 has an upper cylinder 1
When it moves to the 1 side, the pressure in the sub bearing 36 decreases, so that oil is sucked into the sub bearing 36 through the oil suction holes 37, 37 as shown by the arrow in FIG. Then, when the piston 12 moves to the side of the sub bearing 36 below, the oil suction holes 37, 37 are closed, so that the sucked oil flows into the oil pump 38 from the opening 42. The oil that has flowed into the oil pump 38 is compressed in the process of passing through the gradually narrowing outlet passage 43, and is blown out from the small hole 41 at the upper end as shown by the arrow in FIG. 5, and eventually the oil outlet hole of the upper piston portion 12A. Reach 46. The oil that reaches the oil outflow hole 46 is transferred from there to the piston part 1
Since it flows out between 2A and the cylinder portion 11A, the sliding portion between the cylinder 11 and the piston 12A is smooth and sufficiently lubricated, and the durability and reliability are improved.

Next, FIG. 6 shows another structure of the oil pump 38 of the linear compressor 1 of the present invention. In this case, the oil pump 38 is composed of a valve seat 51 attached to the lower end of the piston 12, a valve body 52, a spring 53 as a spring member, and a base plate 54 located above the valve seat 51. The inner surface of the valve seat 51 has an opening 5 at the lower end.
The inclined surface gradually expands from 1A, and the substrate 54
A gap 54A is formed between the inner surface and the inner surface of the piston 12. The valve body 52 is disposed on the opening 51A of the valve seat 51, and is closed so as to be openable and closable.
Is pressed against the opening 51A of the valve seat 51 to urge it to close.

With the above construction, when the piston 12 moves to the upper cylinder 11 side, the oil suction hole 37,
Oil is sucked into the sub bearing 36 from 37. Then, when the piston 12 moves to the lower sub bearing 36 side,
Since the oil suction holes 37, 37 are closed, the auxiliary bearing 36
The pressure inside rises. This pressure causes the spring 53
Against this, the valve body 52 rises and opens the opening 51A of the valve seat 51. As a result, the oil sucked into the sub bearing 36 flows into the piston 12 through the opening 51A as shown by the arrow in FIG.
Since it reaches the oil outflow hole 46 of A, the sliding portion between the cylinder 11 and the piston 12 is smooth and sufficiently lubricated, and the durability and reliability are improved.

Although the inner surface of the valve seat 51 is an inclined surface in FIGS. 6 and 7, the present invention is not limited to this, and it may be a simple plate as shown in FIG. It can be configured with.

Next, FIG. 9 shows another structure of the oil outlet hole 46 portion of the linear compressor 1 of the present invention. In this case, on the outer surface of the piston portion 12A on which the piston 12 and the cylinder 11 slide, a groove 61 that is continuous with the oil outflow hole 46 and extends downward is formed. Also,
An annular oil reservoir 62 is attached inside the piston 12 corresponding to the inside of the oil outflow hole 46.

As a result, as described above, the oil pump 3
The oil that has flowed into the piston 12 due to 8 is stored in the oil sump 62, then flows out from the oil outflow hole 46, enters the groove 61, and flows down.
The entire sliding portion between the piston 1 and the piston 12 can be smoothly spread. This ensures that the storage area is well lubricated,
Durability and reliability can be improved. Incidentally, the groove 61
If the extending direction of the is inclined with respect to the vertical direction as shown in FIG. 11, the oil can be spread over a wider range.

Further, as shown in FIG. 12, a hole 63 communicating with the inside of the piston 12 may be formed at the lower end of the groove 61. According to this structure, the pressure in the groove 61 due to the hole 63 is
Since it will be balanced with the inside, the oil outflow hole 46
The oil easily enters the groove 61. Further, as shown in FIG. 13, a narrow groove 64 extending further downward from the lower end of the groove 61 may be formed. The narrow groove 64 is formed in the cylinder portion 11A of the cylinder 11 when the piston 12 descends to the bottom dead center.
It should face downward. As a result, the inside of the groove 61 communicates with the low-pressure region in the closed container 2 via the narrow groove 64, so that oil easily enters the groove 61 from the oil outflow hole 46, and the sliding portion between the cylinder 11 and the piston 12 is made. Can be lubricated more smoothly and effectively.

[0029]

According to the first aspect of the invention, when the piston moves to the cylinder side, oil is sucked into the sub bearing through the oil suction hole, and when the piston moves to the sub bearing side, this suction is performed. Oil flows into the oil pump through the opening. The oil that has flowed into the oil pump is compressed in the process of passing through the blowout passage and is blown out from the small holes to reach the oil outflow hole of the piston part, so the sliding part between the cylinder and piston is smooth and sufficiently lubricated. The durability and reliability are improved.

According to the second aspect of the invention, when the piston moves to the cylinder side, oil is sucked into the sub bearing through the oil suction hole, and when the piston moves to the sub bearing side, the pressure is applied to the spring member. Against this, the valve body opens the opening of the oil pump. As a result, the oil sucked into the sub-bearing flows in through the opening and eventually reaches the oil outflow hole in the piston part, so that the sliding part between the cylinder and the piston is smooth and sufficiently lubricated, and durability is improved. Improves reliability.

According to the third aspect of the present invention, since the groove which is continuous with the oil outflow hole is formed in the piston portion of the piston, the oil supplied from the oil pump and outflowed from the oil outflow hole slides between the cylinder and the piston. The whole moving part will be smoothly distributed. As a result, the storage portion is sufficiently lubricated, and durability and reliability can be improved.

[Brief description of drawings]

FIG. 1 is a vertical side view of a linear compressor of the present invention.

FIG. 2 is an enlarged vertical sectional side view of an oil pump portion of the linear compressor of the present invention.

FIG. 3 is a diagram showing another embodiment of FIG.

FIG. 4 is a diagram illustrating the operation of the oil pump of FIG.

FIG. 5 is a diagram for explaining the operation of the oil pump of FIG.

FIG. 6 is an enlarged vertical side view of an oil pump portion of another linear compressor of the present invention.

FIG. 7 is a diagram illustrating an operation of the oil pump of FIG.

FIG. 8 is a diagram showing another embodiment of the oil pump of FIG.

FIG. 9 is an enlarged vertical sectional side view of an oil outlet hole portion of a linear compressor according to still another embodiment of the present invention.

10 is a front view of the oil outflow hole and groove of FIG. 9. FIG.

11 is a diagram showing another embodiment of FIG.

FIG. 12 is an enlarged vertical side view of an oil outflow hole portion of a linear compressor of the present invention showing another embodiment of FIG. 9.

FIG. 13 is a front view of an oil outflow hole and a groove showing another embodiment of FIG.

[Explanation of symbols]

 1 Linear Compressor 2 Airtight Container 3 Electric Element 4 Compression Element 7 Oscillator 11 Cylinder 11A Cylinder Part 12 Piston 12A Piston Part 36 Secondary Bearing 37 Oil Suction Hole 38 Oil Pump 41 Small Hole 42 Opening 43 Blowout Passage 46 Oil Outflow Hole 51A Opening 52 Valve body 53 Spring 61 Groove

Claims (3)

[Claims] 1. A linear compressor comprising an electric element and a compression element housed in a closed container, the compression element comprising a cylinder and a piston attached to an oscillator of the electric element to reciprocate. A piston portion formed at one end of the piston and reciprocally freely inserted into the cylinder; and an auxiliary bearing provided at a position facing the cylinder and reciprocally holding the other end of the piston. The oil pump includes an oil suction hole formed in the auxiliary bearing, an oil outflow hole formed in the piston portion of the piston, and an oil pump provided at the other end in the piston. A linear hole that communicates with the sub-bearing, an opening that opens into the sub-bearing, and an outlet passage that gradually narrows from this opening toward the small hole. Presser. 2. A linear compressor comprising an electric element and a compression element housed in a hermetic container, the compression element including a cylinder and a piston attached to an oscillator of the electric element to reciprocate. A piston portion formed at one end of the piston and reciprocally freely inserted into the cylinder; and an auxiliary bearing provided at a position facing the cylinder and reciprocally holding the other end of the piston. The oil pump includes an oil suction hole formed in the auxiliary bearing, an oil outflow hole formed in the piston portion of the piston, and an oil pump provided at the other end in the piston. And a sub-bearing communicating with each other, a valve body closing the opening from the inside of the piston, and a spring member for constantly pressing the valve body against the opening. Linear compressor to be. 3. A linear compressor comprising an electric element and a compression element housed in a hermetic container, the compression element including a cylinder and a piston attached to an oscillator of the electric element to reciprocate. A piston portion formed at one end of the piston and freely reciprocally inserted in the cylinder, an oil outflow hole formed in the piston portion, and an oil outflow hole provided at the other end in the piston, the oil outflow hole being provided in the oil outflow hole. A linear compressor comprising an oil pump for supplying oil, and a groove continuous with the oil outflow hole is formed on an outer surface of the piston portion.