JPH08135585A - Slide member for rotary pump for freezer - Google Patents

Abstract

PURPOSE: To provide excellent slide characteristics by a method wherein a slide member is formed of an alloy steel on which chrome nitride surface treatment indicating excellent slide characteristics under coexistence of HFC fluorocarbon and fluorocarbon oil is applied, in a rotary pump for freezer using HFC fluorocarbon as a refrigerant and fluorocarbon oil as lubrication oil. CONSTITUTION: In a rotary pump for a freezer wherein HFC fluorocarbon is used as a refrigerant and fluorocarbon oil is used as lubricating oil, powder high-speed steel (SKH-51) is employed as the body 24a of a vane 24 as a slide member and after the powder high-speed steel is sintered and molded in the shape of the vane of a rotary compressor, the surface of a slide part 24b on the tip side of the body part 24a is coated with a chrome nitride layer. Further, instead of the chrome nitride layer, a vanadium carbide layer, an acid nitride- oxide layer, a chrome oxide layer, and a teflon-contained chrome layer may be used. A substance prepared by fluorocarbon oil having a fluorine-containing aromatic compound or a fluorine-containing aliphatic compound is used as fluorine-based lubrication oil.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a sliding member suitable for a sliding member of a rotary pump for a refrigerator, such as a vane (blade) member for a rotary compressor, a rotor member, and a movable scroll of a scroll compressor. It is about.

[0002]

2. Description of the Related Art A rotary compressor used in a refrigerator such as an air conditioner, as shown in FIG. 5, is a cast iron rotary cylinder 21 and a rotor eccentrically supported in the rotary cylinder 21. 22, a vane 24 slidably fitted in a vane groove 23 on the inner peripheral surface side of the rotary cylinder 21 and always in sliding contact with the surface of the rotor 22, a front head and a rear head on both sides of the rotary cylinder 21. It is configured. Then, when the drive motor rotates, the rotor 22 eccentrically rotates in the rotary cylinder 21 due to the rotation of the cam of the cam shaft portion 25, whereby the refrigerant gas G flows into the rotary cylinder 21 through the suction port 26. It is compressed and discharged from the discharge port 27. At this time, the vane 2
4 indicates the rotor 2 according to the eccentric rotation of the rotor 22.
2 Performs reciprocating sliding (withdrawal) movement at a considerable speed in the radial direction.

By the way, the relative sliding members, such as the rotor 22 and the vanes 24, which come into contact with each other and slide, are generally made of steel or cast iron in view of wear resistance and thermal expansion coefficient. . Iron-based sliding members such as steel and cast iron
Current CFC refrigerants (CFC, HCFC22, etc.) and lubricating oil
In a mixed oil of (sniso oil), it shows very good sliding characteristics, has high wear resistance, and has a large seizure load. This is because chlorine (Cl) is contained in the existing CFC refrigerants (CFC, HCFC22), so that the chlorine (Cl) is transferred to iron chloride (FeCl ₂ , FeCl ₂ ) on the sliding surface of the iron-based sliding member. ₃ ) is formed, whereby the extreme pressure action is realized.

[0004]

However, as interest in global environmental protection has increased in recent years, the production and use of CFCs that affect ozone depletion in the stratosphere have been regulated, and research on alternative products has been promoted in various fields. ing. Especially regarding lubrication, CF containing Cl as described above
As C and HCFC-based CFCs are being regulated, alternative CFCs that do not contain Cl and are incompatible with existing lubricating oils are being investigated, and therefore, it is necessary to use CFCs with sufficient lubricating oils such as the above existing CFCs. It has become a problem that the degree of mixing and the extreme pressure action of Cl in the flon molecule are eliminated, and the lubricating characteristics are significantly reduced.

In particular, in recent air conditioners, the adoption of an inverter type phase control system is mainly used for controlling the air conditioning capacity, so that the compressor is also highly required to have high-speed sliding performance, and the above-mentioned CFC alternatives are used. Deterioration of lubrication performance is an important theme to be solved.

In response to this, powdered high speed steels containing various ceramic particles and solid lubricants, and surface treatment materials such as nitriding / sulfurizing have been investigated, but all have reached the required lubricating property level. Absent. In addition, for example, JP-A-2-28
As shown in Japanese Patent No. 2437, it has been considered to manufacture each of the sliding members such as the rotor and the vane from an aluminum composite alloy which is lightweight and has high wear resistance. Certainly, when the mass is reduced, it is advantageous in terms of wear resistance and improvement of the seizure load. However, in the case of the aluminum composite alloy, there is a problem in hardness as compared with high-speed steel (SKH51), and the wear resistance and the seizure load itself have not yet reached a sufficiently satisfactory level. Is the reality.

As is clear from the above description, the sliding characteristics of the sliding member largely depend on the type of lubricating oil used and the type of lubricating oil determined by the relationship with the used refrigerant. That is, as described above, a new HFC-based CFC containing no chlorine (for example, HFC32 / HFC134a /
HFC125, etc.) cannot be used for conventional mineral oils such as suniso oil as the lubricating oil for the above reasons. For this reason, for example, use of a fluorine-based lubricating oil that is compatible with the new refrigerant is considered. (For example, WO94
/ 17023, JP-A-3-205491, JP-A-6-49472, JP-A-6-57275).

In the case of such a fluorine-based oil, the above HF
It is compatible with C-based CFCs and can improve the sliding characteristics to some extent. However, according to the experimental results, the level is still not sufficiently satisfactory. In particular,
When the normal high-speed steel (SKH51) is used as the vane material, the seizure load and wear resistance are still low.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a sliding member which adopts the above-mentioned CFC substitute and a fluorine-based lubricating oil and has good sliding characteristics suitable for operating conditions. It is intended.

[0010]

The invention described in each of claims 1 to 7 of the present application is configured to have the following problem solving means in order to achieve the object.

(1) Structure of the invention of claim 1 The sliding member of the rotary pump for a refrigerator of the invention of claim 1 is for a refrigerator using HFC-based CFC as a refrigerant and fluorine-based oil as a lubricating oil. In the rotary pump, the sliding member is made of a chromium nitride surface-treated alloy steel exhibiting good sliding characteristics in the coexistence of the HFC-based fluorocarbon and the fluorine-based oil.

(2) Structure of the invention of claim 2 The sliding member of the rotary pump for a refrigerator of the invention of claim 2 is for a refrigerator using HFC-based CFC as a refrigerant and fluorine-based oil as a lubricating oil. In the rotary pump, the sliding member is made of vanadium carbide surface-treated alloy steel that exhibits good sliding characteristics in the coexistence of the HFC-based fluorocarbon and the fluorine-based oil.

(3) Structure of the invention of claim 3 The sliding member of the rotary pump for a refrigerator of the invention of claim 3 is for a refrigerator using HFC-based CFC as a refrigerant and fluorine-based oil as a lubricating oil. In the rotary pump, the sliding member is made of oxynitride-oxidized surface-treated alloy steel that exhibits good sliding characteristics in the coexistence of the HFC-based fluorocarbon and the fluorine-based oil.

(4) Structure of the invention of claim 4 The sliding member of the rotary pump for a refrigerator of the invention of claim 4 is for a refrigerator using HFC-based CFC as a refrigerant and fluorine-based oil as a lubricating oil. In the rotary pump, the sliding member is formed of a chromium oxide surface-treated alloy steel exhibiting good sliding characteristics in the coexistence of the HFC-based fluorocarbon and the fluorine-based oil.

(5) Structure of the invention of claim 5 The sliding member of the rotary pump for a refrigerator of the invention of claim 5 is for a refrigerator using HFC-based CFC as a refrigerant and fluorine-based oil as a lubricating oil. In the rotary pump, the sliding member is made of a Teflon-containing chromium surface-treated alloy steel that exhibits good sliding properties in the coexistence of the above HFC-based CFCs and fluorine-based oil.

(6) Configuration of the Invention of Claim 6 The sliding member of the rotary pump for a refrigerator of the invention of Claim 6 is a fluorine-based lubrication in the configuration of the invention of Claims 1 to 5 above. The oil is composed of a fluorine-based oil having a fluorine-containing aromatic compound.

(7) Structure of the invention of claim 7 The sliding member of the rotary pump for a refrigerator of the invention of claim 7 is a fluorine-based lubricant in the structure of the invention of claims 1 to 5 above. The oil is composed of a fluorine-based oil having a fluorine-containing aliphatic compound.

[0018]

The sliding members of the rotary pump for a refrigerator according to the invention described in each of claims 1 to 7 of the present application are configured as described above, and as a result, the following actions are performed corresponding to each configuration. Play.

(1) Action of the invention described in claim 1 In the sliding member of the rotary pump for a refrigerator according to the invention described in claim 1, for a refrigerator using HFC type Freon as a refrigerant and fluorine type oil as a lubricating oil. In the rotary pump, the sliding member is formed of a chromium nitride surface-treated alloy steel that exhibits good sliding characteristics on the sliding surface in the coexistence of the above HFC-based CFCs and fluorine-based oil.

As described above, when a chromium nitride layer is formed on the surface of the sliding portion of the alloy steel as the base material by means such as coating, the surface of the alloy steel has a good sliding property due to the reaction with the fluorine-based oil. The compound layer is formed, and the sliding performance is improved.

(2) Operation of the invention of claim 2 In the sliding member of the rotary pump for a refrigerator of the invention of claim 2, for a refrigerator using HFC-based CFC as a refrigerant and fluorine-based oil as a lubricating oil. In the rotary pump, the sliding member is made of a vanadium carbide surface-treated alloy steel which has good sliding characteristics on the sliding surface in the presence of the above HFC-based CFCs and fluorine-based oil.

As described above, when the vanadium carbide layer is formed on the surface of the sliding portion of the alloy steel as the base material by means such as coating, the surface of the sliding portion has a good sliding property due to the reaction with the fluorine-based oil. The compound layer is formed, and the sliding performance is improved.

(3) Action of the invention of claim 3 In the sliding member of the rotary pump for a refrigerator of the invention of claim 3, for a refrigerator using HFC Freon as a refrigerant and fluorine oil as a lubricating oil. In the rotary pump, the sliding member is made of oxynitride-oxidized surface-treated alloy steel that exhibits good sliding characteristics in the coexistence of the HFC-based fluorocarbon and the fluorine-based oil.

As described above, when an oxynitriding oxide layer is formed on the surface of the sliding portion of the alloy steel as the base material by means of coating or the like, the surface of the sliding portion has a high hardness due to the reaction with the fluorine-based oil. A fluoride layer having good properties is effectively formed, and sliding performance is improved.

(4) Action of the invention of claim 4 In the sliding member of the rotary pump for a refrigerator of the invention of claim 4, for a refrigerator using HFC type CFC as a refrigerant and fluorine type oil as a lubricating oil. In the rotary pump, the sliding member is formed of a chromium oxide surface-treated alloy steel exhibiting good sliding characteristics in the coexistence of the HFC-based fluorocarbon and the fluorine-based oil.

As described above, when a chromium oxide layer is formed on the surface of the sliding portion of the alloy steel as the base material by means such as coating, a fluoride having a good slidability is formed on the surface by reaction with the fluorine-based oil. The layer is formed to improve the sliding performance.

(5) Action of the invention of claim 5 In the sliding member of the rotary pump for a refrigerator of the invention of claim 5, for a refrigerator using HFC type CFC as a refrigerant and fluorine type oil as a lubricating oil. In the rotary pump, the sliding member is made of a Teflon-containing chromium surface-treated alloy steel that exhibits good sliding properties in the coexistence of the above HFC-based CFCs and fluorine-based oil.

As described above, when a chromium layer containing Teflon having particularly good slidability is formed on the surface of the sliding portion of the alloy steel as the base material by means of coating or the like, the surface of the chromium-containing oil is mixed with the above-mentioned fluorine-based oil. By this reaction, a fluoride layer having a better sliding property is formed, and the sliding performance is further improved.

(6) Operation of the invention of claim 6 The sliding member of the rotary pump for a refrigerator of the invention of claim 6 has the fluorine-based lubrication in the constitution of the invention of each of claims 1 to 5 above. The oil is composed of a fluorine-based oil having a fluorine-containing aromatic compound.

Fluorine-based oils containing a fluorine-containing aromatic compound show good compatibility with the above HFC-based CFCs in a wide temperature range from a low temperature region to a high temperature region, and since they contain fluorine, the surface of the sliding portion is The fluoride layer is well formed.

(7) Action of the invention of claim 7 In the sliding member of the rotary pump for refrigerator of the invention of claim 7, the fluorine-based lubrication in the constitution of the invention of each of claims 1 to 5 is used. The oil is composed of a fluorine-based oil having a fluorine-containing aliphatic compound.

Fluorine-based oils containing a fluorine-containing aliphatic compound show good compatibility with the above HFC-based CFCs in a wide temperature range from a low temperature range to a high temperature range. The fluoride layer is well formed.

[0033]

As a result of the above, according to the sliding member of the rotary pump for a refrigerator of the above inventions of the present application, even when the alloy steel such as general high speed steel (SKH51) is used as the base material, the new refrigerant and Good sliding characteristics can be realized in combination with a compatible fluorine-based lubricating oil that is compatible with the new refrigerant, and a significant reduction in lubricating characteristics due to the use of an alternative refrigerant due to recent CFC regulations, The level of seizure resistance and wear resistance can be sufficiently improved in response to the increase in the sliding speed due to the use of an inverter. As a result, the speed of the rotating part such as the inverter control can be increased, and the operating conditions of the refrigerator can be expanded.

[0034]

【Example】

(1) First Embodiment First, a first embodiment of the present invention will be described in detail with reference to FIGS.

First, in this embodiment, as the sliding member main body 24a, for example, a powder high speed steel (SKH51) having a component weight ratio in the whole as shown in the following (Table 1) is adopted, which is used for an air conditioner, for example. After sinter-molded into the vane shape of the rotary compressor, the sliding portion 24b on the tip side of the main body portion 24a thereof
By coating the surface with a chromium nitride layer, a vane 24 as a rotary compressor sliding member as shown in FIG. 1 is manufactured.

[0036]

[Table 1]

Then, the vane 24 is used to construct a rotary compressor having a structure similar to that of FIG. 5 described above, and HFC type mixed freon (HFC32 / HFC13) is used as a refrigerant.
4a), a fluorine-based oil represented by the following (Chemical formula 1) is used as the lubricating oil.

[0038]

Embedded image

(2) Second Embodiment Next, a second embodiment of the present invention will be described in detail.

First, in this embodiment, as the sliding member main body 24a, for example, the powder high speed steel (SKH51) whose component weight ratio is as shown in the above (Table 1) is adopted, and the same vane as in the above Example 1 is used. After being sintered and formed into a shape, its main body 24
a A vane 24 as a sliding member for a rotary compressor as shown in FIG. 1 is manufactured by coating the surface of the sliding portion 24b on the tip side with a vanadium carbide layer.

The vane 24 is used to construct a rotary compressor having a structure similar to that of FIG. 5 described above, and HFC-based mixed freon (HFC32 / HFC13) is used as a refrigerant.
4a), the fluorine-based oil represented by the above (Chemical formula 1) was used as the lubricating oil.

(3) Third Embodiment The third embodiment of the present invention will be described in detail below.

First, in this embodiment, for example, as the sliding member main body 24a, the powder high speed steel (SKH51) whose component weight ratio is as shown in the above (Table 1) is adopted, and the same vane as in the above Example 1 is used. After being sintered and formed into a shape, its main body 24
a The vane 24 as a sliding member for a rotary compressor as shown in FIG. 1 is manufactured by coating the surface of the sliding portion 24b on the tip side with an oxynitride oxide layer.

Then, the vane 24 is used to construct a rotary compressor having a structure similar to that of FIG. 5 described above, and HFC mixed freon (HFC32 / HFC13) is used as a refrigerant.
4a), the fluorine-based oil represented by the above (Chemical formula 1) was used as the lubricating oil.

(4) Fourth Embodiment The fourth embodiment of the present invention will be described in detail below.

First, in this embodiment, for example, as the sliding member body 24a, the powder high speed steel (SKH51) having the component weight ratio as shown in the above (Table 1) is adopted, and the same vane as that in the above first embodiment is used. After being sintered and formed into a shape, its main body 24
a A vane 24 as a sliding member for a rotary compressor as shown in FIG. 1 is manufactured by coating the surface of the sliding portion 24b on the tip side with a chromium oxide layer.

The vane 24 is used to construct a rotary compressor having a structure similar to that shown in FIG. 5, and HFC mixed freon (HFC32 / HFC13) is used as a refrigerant.
4a), the fluorine-based oil represented by the above (Chemical formula 1) was used as the lubricating oil.

(5) Fifth Embodiment Hereinafter, a fifth embodiment of the present invention will be described in detail.

First, in this embodiment, for example, as the sliding member body 24a, the powder high speed steel (SKH51) having the component weight ratio as shown in the above (Table 1) is adopted, and the same vane as that of the above first embodiment is used. After being sintered and formed into a shape, its main body 24
a A vane 24 as a sliding member for a rotary compressor as shown in FIG. 1 is manufactured by coating the surface of the sliding portion 24b on the tip side with a Teflon-containing chromium layer.

The vane 24 is used to construct a rotary compressor having a structure similar to that shown in FIG. 5, and HFC mixed freon (HFC32 / HFC13) is used as a refrigerant.
4a), the fluorine-based oil represented by the above (Chemical formula 1) was used as the lubricating oil.

(Test Example) Then, the test piece of the vane 24 of each of Examples 1 to 5 manufactured as described above (alloy steel sample having base material Vickers hardness Hv 760 to 840) A to
For example, E is subjected to a high-pressure atmosphere vane disc friction tester equipped with a closed pressure vessel as shown in FIG. 2, and a friction test (burning test) in the fluorine-based mixed oil represented by the above (Chemical formula 1). I went.

The friction tester includes a balance support mechanism 5 having a pressure spring 2 having a predetermined elastic coefficient, a load cell 3 for loading, and a sphere 4 on the bottom side of a hermetically sealed pressure vessel 1 in which a refrigerant is sealed. Three test pieces TP ₁ , TP ₂ , TP ₃
Is provided with a fixed disk 6 that can be fixed arbitrarily, and a rotary disk 7 is provided correspondingly to the upper side of the pressure vessel 1, and the rotary disk 7 is rotationally driven by a motor drive shaft 8. And the fixed disc 6 is a rod 9
Is linked to the friction torque load cell 10 via.

The test pieces were made of the samples A, B, C, D, and E described later on the vane-shaped test piece side, and MoNiCr cast iron on the rotating disk side, which was the same as that of the conventional rotor.

In the seizure test, the friction speed was 4 [m / s], the load step was 10 [MPa], and the holding time was 5 [min]. Moreover, seizure was taken as a rapid increase in friction torque, and the load at that time was measured as the seizure load.

The test refrigerants (CFC) are HFC32 and HFC1.
34a is a mixed refrigerant (composition ratio 30/70 wt%). The lubricating oil used was the fluorine-based oil used in each of the examples shown in the above (Chemical formula 1) and compatible with the CFCs of each HFC32 / 134a system, and the ester oil as the comparison lubricating oil. (Compatible with HFC134a). And
For example, the temperature condition is kept constant at 25 [° C] and the amount of dissolved refrigerant is 50%.
Went under.

Further, the test pieces A to E of each of the above embodiments
The Vickers hardness Hv and the film pressure (layer pressure) of the surface treatment part are
It is as shown in the following (Table 2).

[0057]

[Table 2]

The result of the baking test is shown in FIG. FIG. 4 is a graph showing the seizure load data of the samples A to E of the above Examples 1 to 5 each tested by the above method. As is clear from the data, in the samples A to E of Examples 1 to 5 of the invention of the present application, in any of them, the alternative CFC refrigerant H to the current material (high-speed steel SKH51) F is used.
The seizure characteristics are higher when FC32 / 134a and the current ester oil are used. Moreover, it is further improved with respect to the above-mentioned fluorine-based oil. As a result,
It can be seen that according to the sliding member of this embodiment, the sliding characteristics and the seizure characteristics are sufficiently good even with respect to the CFC substitute.

(2) Other Examples In the above examples, as the lubricating oil, the above (Chemical formula 1) was used.
Although it is constituted by using a fluorine oil having an aliphatic compound containing fluorine as shown in, it may be constituted by using a fluorine oil having an aromatic compound containing fluorine. Needless to say.

[Brief description of drawings]

FIG. 1 is a perspective view showing a shape of a sliding member (vane) of a rotary pump for a refrigerator according to Embodiments 1 to 5 of the present invention.

FIG. 2 is a schematic diagram showing a configuration of a test device that performs a friction test of vanes of a rotary pump for a refrigerator according to the first to fifth embodiments.

FIG. 3 is a schematic diagram showing a configuration of a friction test unit of the apparatus.

FIG. 4 is a graph showing seizure characteristic data corresponding to the ester oil and the fluorine-based lubricating oil of the sliding member of each of the above-described examples in comparison with the conventional example.

FIG. 5 is a schematic view showing a structure of a conventional general rotary compressor.

[Explanation of symbols]

Reference numeral 24 is a vane, 24a is a vane body, and 24b is a sliding surface at the tip of the vane on which a coating layer is formed.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Fumihiko Yamaguchi 1-1 No. 1 Nishiichitsuya, Settsu City, Osaka Prefecture Daikin Industries, Ltd. Yodogawa Works (72) Inventor Eiji Seki No. 1 Nishiichitsuya, Settsu City, Osaka Prefecture Daikin Industries, Ltd. Yodogawa Manufacturing Co., Ltd.

Claims (7)

[Claims] 1. A rotary pump for a refrigerator using HFC-based CFC as a refrigerant and fluorine-based oil as a lubricating oil,
A sliding member for a rotary pump for a refrigerating machine, characterized in that the sliding member is made of a chromium nitride surface-treated alloy steel exhibiting good sliding properties in the coexistence of the above HFC-based CFC and fluorine-based oil. . 2. A rotary pump for a refrigerator using HFC-based CFC as a refrigerant and fluorine-based oil as a lubricating oil,
A sliding member for a rotary pump for a refrigerator, characterized in that the sliding member is formed of an alloy steel having a vanadium carbide surface treatment which exhibits good sliding characteristics in the coexistence of the above HFC-based CFCs and fluorine-based oil. . 3. A rotary pump for a refrigerator using HFC-based CFC as a refrigerant and fluorine-based oil as a lubricating oil,
A sliding member for a rotary pump for a refrigerator, characterized in that the sliding member is made of an alloy steel which has been subjected to an oxynitride-oxidation surface treatment which exhibits good sliding characteristics in the coexistence of the above HFC-based CFCs and fluorine-based oil. Element. 4. A rotary pump for a refrigerator using HFC-based CFC as a refrigerant and fluorine-based oil as a lubricating oil,
A sliding member for a rotary pump for a refrigerator, characterized in that the sliding member is formed of an alloy steel having a chromium oxide surface treatment, which exhibits good sliding characteristics in the coexistence of the above HFC-based CFCs and fluorine-based oil. . 5. A rotary pump for a refrigerator using HFC-based CFC as a refrigerant and fluorine-based oil as a lubricating oil,
A sliding member for a rotary pump for a refrigerating machine, characterized in that the sliding member is formed of an alloy steel having a Teflon-containing chromium surface treatment which exhibits good sliding characteristics in the coexistence of the above HFC-based Freon and fluorine-based oil. Element. 6. The refrigerator rotating machine according to claim 1, 2, 3, 4, or 5, wherein the fluorine-based lubricating oil is composed of a fluorine-based oil having a fluorine-containing aromatic compound. Sliding member for pump. 7. The rotating machine for a refrigerator according to claim 1, 2, 3, 4, or 5, wherein the fluorine-based lubricating oil is constituted by a fluorine-based oil having a fluorine-containing aliphatic compound. Sliding member for pump.