JP2006132540A - Bearing of compressor for refrigerator and compressor for refrigerator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bearing of a compressor for a refrigerator and the compressor for the refrigerator provided with it having large proof stress for seizure when lubricating a boundary and capable of reducing amount of wear due to slide. <P>SOLUTION: Porous bronze and resin impregnated in many holes of the porous bronze are formed on a back plate to constitute the bearing 1. The porous bronze and the resin are sparsely exposed on a contact face with a crank shaft 5. A ratio of exposure area of the porous bronze on the contact face is 5% or more and 60% or less. Consequently, it is possible to provide the bearing of the compressor for the refrigerator and the compressor for the refrigerator having large proof stress for seizure when lubricating a boundary and capable of reducing amount of wear due to slide. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a bearing for a compressor for a refrigerator and a compressor for the refrigerator.

  Until now, CFC (chlorofluorocarbon) and HCFC (hydrochlorofluorocarbon) have been used as refrigerants for compressors for refrigerators. However, recently, in order to prevent the ozone layer from being destroyed by chlorine contained in these CFCs and HCFCs, HFC (hydrofluorocarbon) containing no chlorine has been used as an alternative refrigerant.

  With the change of the refrigerant, it is necessary to change the bearing material of the compressor for the refrigerator. This is because the material containing Al (aluminum) that has been used for bearings so far is easily corroded by HFC, which is an alternative refrigerant. Therefore, it has been studied to use a material containing bronze as the material of the bearing. As a technique using a material containing bronze for the bearing, for example, there is JP-A-59-194128.

  The above publication discloses a compressor bearing for a refrigerator formed by sintering a porous bronze alloy impregnated with a composite material composed of a synthetic resin and a lubricant on a back metal. The bearing is formed so that both the porous bronze alloy and the composite material are loosely exposed at the contact surface with the shaft.

  However, the above publication does not disclose the exposure ratio of the porous bronze alloy at the contact surface with the shaft. For this reason, in the bearing of the above publication, seizure resistance at the time of boundary lubrication decreases, seizure occurs, or the amount of wear due to sliding increases, resulting in a larger bearing gap, twisting, seizure, etc. There was a problem that damage occurred.

  Accordingly, an object of the present invention is to provide a bearing for a compressor for a refrigerator having a large seizure resistance during boundary lubrication and a small amount of wear due to sliding, and a compressor for a refrigerator provided with the same.

  As a result of intensive studies, the inventors of the present application have determined that the exposure ratio of the porous bronze alloy on the contact surface (sliding surface) with the shaft in the compressor bearing for the refrigerator is changed to reduce seizure resistance and wear resistance. I found out that gender changes. Further, the inventors of the present application have found that a bearing satisfying both seizure resistance and wear resistance suitable for a bearing for a compressor for a refrigerator can be obtained by setting the exposure ratio within a predetermined range. .

  Accordingly, the bearing for the compressor for a refrigerator according to the present invention includes a porous bronze alloy and a resin material impregnated in the pores of the porous bronze alloy, and the porous bronze alloy and the resin on the sliding surface. The ratio of the exposed area of the porous bronze alloy on the sliding surface is 5% or more and 60% or less.

  In the bearing of the compressor for a refrigerator according to the present invention, the ratio of the exposed area of the porous bronze alloy on the sliding surface is set to 5% or more and 60% or less. This is because when it exceeds 60%, the seizure resistance is extremely lowered and seizure is likely to occur. Thereby, it is possible to obtain a bearing for a compressor for a refrigerator, which has a large seizure resistance at the time of boundary lubrication or the like and a small amount of wear due to sliding.

  The porous bronze alloy was used because the bronze alloy is less likely to corrode against the alternative refrigerant, and the bronze alloy has a high heat transfer coefficient, so that the bearing can be prevented from burning. The reason why the bronze alloy is made porous is that the bronze alloy is firmly bound to the back metal by the resin entering the hole, and the bronze alloy is prevented from spilling due to friction during sliding. The resin material is used to prevent seizure because the bronze alloy alone is likely to seize.

  In addition, it is preferable to expose the porous bronze alloy and the resin material loosely on the contact surface with the shaft, thereby exhibiting the effects of the wear resistance of the bronze alloy and the seizure resistance of the resin material as uniformly as possible. Can be made.

  In this specification, the porous bronze-based alloy means a material including a porous material among bronze, which is an alloy of copper and tin, and is made only of porous bronze, only porous bronze. It shall include materials including other than that.

  In the above-described compressor compressor bearing, the ratio of the exposed area of the porous bronze alloy on the sliding surface is preferably 5% or more and 30% or less.

  The ratio of the exposed area of the porous bronze alloy on the sliding surface is set to 30% or less because the maximum effect of seizure resistance can be obtained in this range.

  The bearing of the compressor for a refrigerator described above preferably further includes a back metal, and a porous bronze alloy and a resin material are formed on the back metal.

  Thus, the resin enters the pores of the porous bronze alloy so that the bronze alloy can be firmly bound to the back metal, and the bronze alloy can be prevented from spilling due to friction during sliding.

  In the above-described compressor compressor bearing, the refrigerant compressed by the refrigerator compressor is preferably a hydrofluorocarbon-based alternative refrigerant that does not contain chlorine.

  By using this alternative refrigerant, destruction of the ozone layer can be prevented, and even when this alternative refrigerant is used, the bearing of the present invention is unlikely to corrode.

  In the above-described compressor compressor bearing, the resin material preferably includes a composite material composed of a synthetic resin and a lubricant.

Thereby, according to each use condition, a resin material can be selected suitably.
In the above-described compressor compressor bearing, the synthetic resin may contain tetrafluoroethylene and the lubricant may contain lead, but the lubricant may not contain lead.

  Thereby, the material of a synthetic resin can be selected appropriately. Lead improves lubricity, but lead is not essential for lubricants.

  In the above-described compressor compressor bearing, the resin material preferably contains an oil-containing polyacetal resin.

Thereby, a resin material can be selected appropriately.
The compressor for a refrigerator of the present invention includes a scroll-type compression element having a movable scroll, a drive shaft for transmitting a driving force to the movable scroll, and a bearing disposed on a sliding portion of the drive shaft, The bearing comprises a porous bronze alloy and a resin material impregnated in the pores of the porous bronze alloy, the porous bronze alloy and the resin material are exposed on the sliding surface, and sliding The ratio of the exposed area of the porous bronze alloy on the surface is 5% or more and 60% or less.

  As a result, a compressor for a refrigerator having a bearing having a high seizure resistance at the time of boundary lubrication and a small amount of wear due to sliding can be obtained.

  In the compressor for a refrigerator described above, the bearing is preferably a sliding bearing disposed at a sliding portion between the movable scroll and the drive shaft.

  Thereby, in the sliding part of a movable scroll and a drive shaft, the seizing strength at the time of boundary lubrication etc. can be enlarged, and the amount of wear by sliding can be reduced.

  In the above compressor for a refrigerator, the bearing is preferably a sliding bearing disposed in a sliding portion between the housing and the drive shaft.

  Thereby, in the sliding part of a housing and a drive shaft, while being able to enlarge the seizing strength at the time of boundary lubrication etc., the amount of wear by sliding can be made small.

  The compressor for a refrigerator described above preferably has a configuration capable of supplying oil to the bearing from an oil supply hole provided in the drive shaft.

  As described above, the bearing used in the present invention has a large seizure resistance and a small amount of wear due to sliding. For this reason, since oil supply to a bearing part temporarily worsens and seizure and abrasion can be prevented even if it becomes a boundary lubrication state, it is suitable for the compressor for refrigerators which has the said oil supply path | route.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
Referring to FIG. 1, a motor (not shown) and a compression element CF are mainly disposed in the sealed container 20.

  An eccentric portion 5a that is eccentric with respect to the crankshaft 5 is provided at an upper end portion of the crankshaft 5 that is coupled to a rotor (not shown) of the motor. The eccentric portion 5a includes a cylindrical slide bush. 3 is loosely fitted. The slide bush 3 is received in the boss portion 11 b of the movable scroll 11. And the inner peripheral surface of the sliding bearing 1 attached to the inner peripheral surface of the boss | hub part 11b and the outer peripheral surface of the slide bush 3 comprise the sliding part. As a result, the driving force of the crankshaft 5 is transmitted to the movable scroll 11 via the slide bush 3, and the movable scroll 11 revolves.

  Due to the revolution of the movable scroll 11, the compression chamber constituted by the spiral tooth portions 11a and 13a of the movable scroll 11 and the fixed scroll 13 moves while gradually reducing the volume from the outer peripheral side to the inner peripheral side of the scroll. . Thereby, the refrigerant gas in the compression chamber is gradually compressed to reach the innermost compression chamber, where it is discharged from the discharge port.

  The crankshaft 5 is provided with an oil supply hole 5b that extends from below (not shown) the compressor for the refrigerator to the end surface of the eccentric portion 5a. Through the oil supply hole 5b, oil is guided from the oil reservoir below the compressor for the refrigerator to the end surface of the eccentric portion 5a, and then supplied to the sliding portion between the slide bearing 1 and the slide bush 3.

Next, the configuration of the plain bearing 1 in FIG. 1 will be described in detail.
With reference to FIG. 2, the sliding bearing 1 has a back metal 1a, a porous bronze 1b, and a resin 1c. The porous bronze 1b and the resin 1c impregnated in the pores of the porous bronze 1b are formed on the back metal 1a. On the contact surface (sliding surface) 1d with the slide bush 3, the porous bronze 1b and the resin 1c are loosely exposed. And the ratio of the exposed area of the porous bronze 1b in the contact surface 1d is 5% or more and 60% or less. The ratio of the exposed area of the porous bronze 1b on the contact surface 1d is preferably 5% or more and 30% or less.

  The inventors of the present application measured the bearing surface pressure and the amount of wear when the ratio of the exposed area of bronze (exposure rate) was changed using the compressor for a refrigerator shown in FIGS. 1 and 2. The results are shown in FIGS.

  First, referring to FIG. 3, it has been found that the bearing surface pressure decreases as the exposure rate of bronze increases. In particular, it was found that when the exposure rate of bronze exceeds 60%, the bearing surface pressure becomes as low as about 3 MPa, and seizure is likely to occur. Further, it was found that if the exposure rate of bronze is 30% or less, the bearing surface pressure can be remarkably increased to about 10 MPa, and the most effective effect of seizure resistance can be obtained.

  Next, referring to FIG. 4, it was found that the amount of wear can be reduced by increasing the exposure rate of bronze. It was also found that the amount of wear increased rapidly when the exposure rate of bronze was less than 5%.

  From the results of FIG. 3 and FIG. 4 above, if the ratio of the exposed area of bronze is 5% or more and 60% or less, a compressor compressor bearing excellent in both seizure resistance and wear resistance can be obtained. It has been found. It was also found that if the bronze exposure rate is 5% or more and 30% or less, a bearing for a compressor for a refrigerator having further excellent seizure resistance can be obtained.

  Thus, since the sliding bearing 1 of this embodiment is excellent in both seizure resistance and wear resistance, the sliding portion between the sliding bearing 1 and the slide bush 3 through the oil supply hole 5b as shown in FIG. It is particularly suitable for a compressor for a refrigerator having a structure for supplying oil.

  In the present embodiment, the porous bronze 1b is used, but the material is not limited to the porous bronze 1b, and a material containing porous bronze may be used. In that sense, a porous bronze alloy is used. May be. Resin 1c is used, but a material containing resin, for example, a composite material composed of a synthetic resin and a lubricant may be used for this portion 1c, and PTFE (tetrafluoroethylene) and lead may be used. Including materials may be used. In this case, lead serves to improve lubricity. Further, the material of the resin 1c may include an oil-containing polyacetal resin.

  In the configuration of FIG. 1, a rolling bearing 9 is used to support the crankshaft 5 with the upper housing 7, but instead of the rolling bearing 9, a backing metal 1a and a porous bronze 1b are used as shown in FIG. The slide bearing 1 having the configuration shown in FIG. 2 and made of the resin 1c may be used. Although not shown in FIG. 1, a slide bearing having the configuration shown in FIG. 2 may be used between the lower housing and the crankshaft 5.

  In the configuration of FIG. 1, the scroll type compression element CF has been described. However, the compression element is not limited to this, and any compression element may be used as long as it is used in a refrigerator.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  INDUSTRIAL APPLICABILITY The present invention can be advantageously applied to a bearing for a compressor for a refrigerator that requires seizure resistance and wear resistance and a compressor for a refrigerator that includes the bearing.

It is a schematic sectional drawing which shows partially the structure of the compressor for refrigerators in one embodiment of this invention. It is a figure which shows the cross-section of a slide bearing. It is a figure which shows the relationship between the bronze exposure rate in the contact surface with a crankshaft, and a printing surface pressure. It is a figure which shows the relationship between the bronze exposure rate in the contact surface with a crankshaft, and the amount of wear. It is a schematic sectional drawing which shows a mode that the sliding bearing has been arrange | positioned at the sliding part of a housing and a crankshaft.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Slide bearing, 1a Back metal, 1b Porous bronze, 1c resin, 5 Crankshaft, 11 Moveable scroll.

Claims (4)

A bearing (1) for a compressor for a refrigerator includes a porous bronze alloy (1b) and a resin material (1c) impregnated in the pores of the porous bronze alloy (1b), and a sliding surface The ratio of the exposed area of the porous bronze alloy (1b) on the sliding surface (1d) in which the porous bronze alloy (1b) and the resin material (1c) are exposed in (1d) Is 5% or more and 60% or less,
The refrigerant compressed by the compressor for the refrigerator is a hydrofluorocarbon-based alternative refrigerant that does not contain chlorine,
The said resin material (1c) is a bearing of the compressor for refrigerators containing the composite material which consists of a synthetic resin and the lubricant which does not contain lead. Further provided with a backing metal (1a),
The bearing of the compressor for refrigerators of Claim 1 with which the said porous bronze type alloy (1b) and the said resin material (1c) are formed on the said back metal (1a). A scroll-type compression element (CF) having a movable scroll (11);
A drive shaft (5) for transmitting a drive force to the movable scroll (11);
A bearing (1) disposed in a sliding portion with the drive shaft (5),
The bearing (1) includes a porous bronze-based alloy (1b) and a resin material (1c) impregnated in the holes of the porous bronze-based alloy (1b). The porous bronze alloy (1b) and the resin material (1c) are exposed, and the ratio of the exposed area of the porous bronze alloy (1b) to the sliding surface (1d) is 5% or more 60 % Or less,
The refrigerant compressed by the compression element (CF) is a hydrofluorocarbon-based alternative refrigerant that does not contain chlorine,
The said resin material (1c) is a compressor for refrigerators containing the composite material which consists of a synthetic resin and the lubricant which does not contain lead.   The compressor for a refrigerating machine according to claim 3, wherein oil is supplied to the bearing (1) from an oil supply hole (5b) provided in the drive shaft (5).

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