JP2001221182A - Vane for compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vane for a compressor which can be produced with high efficiency, and having wear resistance and scuffing resistance. SOLUTION: The vane for the compressor having a spring seat for engaging a spring on a rear end part is formed in a near-net-shape, and only tip end part is polished. C of 0.5 to 2.5 %, Si of 2.5 % or less, Mn of 1.0 % or less, Ni of 0.6 % or less, and Cr of 3.0 to 20.0 % are included, and one kind or two or more kinds of Mo, W, and V are included by 20 % or less in the total, and the rest is compound which is composed of Fe and inevitable impurity.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a compressor for use in a refrigerator or an air conditioner, and more particularly to an improvement in a compressor vane.

[0002]

2. Description of the Related Art As a compressor used in a refrigerator or an air conditioner, a rolling compressor generally expected to have a high pressure ratio is generally used. FIG. 2 is a sectional view showing an example of the rolling compressor. In the rolling compressor 1,
A roller 5 rotatably mounted on the outer periphery of an eccentric part 4 formed in a part of the rotating shaft 2 and mounted in the cylinder 3 rotates the inner surface of the cylinder 3 while contacting a flat vane 6. To compress the gas in the cylinder. At this time, the vane 6 is urged by the spring 7 to always contact the outer periphery of the roller 5 and reciprocate in the groove 8 formed in the cylinder 3 while sliding on the outer periphery of the roller 5. Similarly, it is always in contact with one of the inner surfaces to maintain airtightness.

FIG. 1 shows the shape of the vane. The vane has a flat plate shape, and a surface R at the tip end sliding on the outer peripheral surface of the compressor roller,
When the vane reciprocates in the groove in the compressor cylinder, it has front and back surfaces S consisting of two parallel surfaces that slide on the inner surface of the groove, and side surfaces H that slide in contact with the side walls of the compressor cylinder groove. are doing. A spring seat 9 is formed at the rear end of the vane, and is configured to form a receiving seat at one end of the spring 7. The other end of the spring 7 contacts the wall of the cylinder 3 and urges the vane 6 so that the vane 6 contacts the outer peripheral surface of the roller 5.

[0004] These vanes are required to be excellent in wear resistance and low in aggressiveness of a mating material in order not to wear a roller or a cylinder of a sliding material. For this reason, vanes use high-speed tool steel (SKH 51), S
It was manufactured using a steel material such as stainless steel such as US 440C. Usually, the vane is cut into a plate-like material (FIG. 3A) having one of the width-direction end surfaces as a curved surface by forging, groove rolling, drawing, or the like, using the above-described steel material as a material, at a predetermined length in the longitudinal direction. And a vane material of approximately predetermined dimensions (Fig. 3
(B)), a spring seat (FIG. 3 (c)) having a predetermined shape is machined or machined by a milling machine or a broach at the other end to obtain a product shape.

[0005] However, the vane manufactured by such a conventional vane manufacturing method suffers from scuffing and abrasion under a high load, and is inferior in abrasion resistance and scuffing resistance. Requires multiple steps of processing. In particular, processing of the spring seat requires a large number of man-hours, and there is a problem that productivity is reduced and cost is increased.

[0006]

SUMMARY OF THE INVENTION The present invention advantageously solves the above-mentioned problems of the prior art and provides a compressor vane which can be produced with high efficiency, is inexpensive, and has excellent wear resistance. With the goal.

[0007]

Means for Solving the Problems The present inventors have diligently studied to improve the productivity in order to achieve the above object. As a result, a lot of man-hours and costs are spent on machining the spring seat of the vane.
I came up with the idea to shape the vane material into a near-net-shape shape including the spring seat. Precision molding and MIM (Metal Injection Mold) are known as molding methods having high dimensional accuracy. Above all, precision casting has high dimensional accuracy and low occurrence of internal defects even in complicated shapes. From the above, the present inventors have conceived of applying a material using a precision casting method to the material of the compressor vane.

[0008] By using a precision casting method, the compressor vane is cast into a near-net-shape shape including a spring seat, thereby making the spring seat unprocessed and reducing the number of polishing steps. It was found that it could be a product. By using a precision casting method, and by using a specific composition to further improve the wear resistance, or by applying a wear-resistant surface treatment to the sliding surface, a compressor vane with significantly improved wear resistance is obtained. It was found that it can be manufactured at low cost and with high production efficiency.

The present invention has been made based on the above findings. That is, according to the present invention, a spring is inserted into a groove formed in a radial direction of a cylinder of a compressor, a spring is engaged with a rear end portion, and a leading end portion is brought into contact with an outer peripheral surface of a roller disposed in the cylinder. A sliding vane for a compressor, having a flat plate shape having a curved or rounded tip portion, and a spring seat for engaging the spring at the rear end portion, formed by precision casting. And a polishing vane. Further, in the present invention, the vane for the compressor has a C: 0.5 to 0.5% by mass.
2.5%, Si: 2.5% or less, Mn: 1.0% or less, Ni: 0.6%
Hereinafter, Cr contains 3.0 to 20.0%, and further contains one or more of Mo, W and V in a total amount of 20% or less, and the balance
It is preferably made of a precision cast material having a composition consisting of Fe and unavoidable impurities. Further, in the present invention, the compressor vane has a nitride layer, a wear-resistant film formed by an ion plating method on its surface, or a nitride layer and a wear-resistant film formed by an ion plating method as an upper layer thereon. It is preferable that a conductive film is formed.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The compressor vane of the present invention is a vane manufactured by using a precision casting method, and has a flat plate shape as shown in FIG. The surface R is a curved surface or an R shape having a predetermined radius of curvature,
The rear end has a spring seat. Note that only the surface R is subjected to polishing after casting.

The shape of the spring seat in the compressor vane of the present invention is selected so as to fit a spring according to the compressor, and is not limited to the shape shown in FIG. An example of a spring seat suitable for the vane of the present invention is shown in FIG. Further, in the present invention,
For example, as shown in FIG. 4B, a projection 10 surrounded by a groove may be provided. The protruding portion has a role of stabilizing in the slide-down groove due to the slope of the protruding portion 10 when the end of the spring rises during sliding of the vane and tends to shift to any of up, down, left and right. By having such a projection 10, it is easier to prevent the spring 7 from shifting and to make the operating axis of the spring always coincide with the sliding direction of the vane.

The shapes of the projections are shown in FIGS.
Although not limited to the example shown in (d), it is preferable to form a circle or a trapezoid in the direction of the spring from the viewpoint of preventing displacement. The compressor vane of the present invention is manufactured by a precision casting method. The method for producing the compressor vane of the present invention will be described.

First, a flat plate-shaped wax vane model for a compressor, for example, as shown in FIG. 1, having a curved surface or an R-shaped end and a spring seat at a rear end, is prepared by injection molding. . Materials for wax models include wax,
Polystyrene or urea resin can be used in place of wax or plastics, or urea resin is more preferable from the viewpoint of strength.

The procedure for producing a wax model will be described with reference to an example using a urea resin. The granular urea resin powder is mixed and melted in water, and further added with polyvinyl alcohol and dissolved while heating to form a solution. The solution is cooled to crystallize out a crystal. Then, the crystallized product is put into an injection molding machine as a powder to obtain a wax model having a desired shape.

Next, a refractory is coated in a layer around the obtained model. The coating is preferably immersed in a slurry obtained by mixing a filler of refractory fine powder in a binder such as colloidal silica, and then repeatedly performing a process of adhering stucco particles such as zircon sand a plurality of times. Refractory adheres in layers.

Next, the model on which the refractory is adhered is dried and hardened, and then the wax model is eluted to form a shell-shaped mold.
This shell-shaped model is fired at a high temperature to obtain a mold. By using such a mold, a compressor vane having a near-net-shape shape can be cast. A molten metal having a predetermined composition is injected into the mold prepared in the above-described steps. After injection
After solidification, the product is removed from the mold. By using such a mold, a vane for a compressor having a near-net-shape shape can be easily cast.

After the surface of the product taken out of the mold is cleaned by shot blasting or the like, it is subjected to heat treatment or surface treatment such as quenching and tempering, if necessary, and further, only the tip portion which is the sliding surface is slightly polished. And then ship it as a product. In the present invention, as a surface treatment, a nitride layer, or a wear-resistant film formed by an ion plating method on a vane surface for a compressor, particularly a sliding surface, or a nitride layer and an ion plating method as an upper layer thereon. The formed wear-resistant film may be formed.

The nitride layer is preferably a nitride layer formed by a gas nitriding method or an ion nitriding method. Chromium nitride (CrN, Cr ₂ N, or a mixture thereof) is used as the wear-resistant film formed by the ion plating method.
Is preferred. By forming these nitrided layers and / or a wear-resistant film formed by ion plating on the surface of the compressor vane, there is an effect that the wear resistance is improved and the friction coefficient is reduced.

The composition of the compressor vane or molten metal of the present invention is, in mass%, C: 0.5 to 2.5%, Si: 2.5% or less, Mn: 1.0% or less, Ni: 0.6% or less, Cr: 3.0 to 2.5%. 20.0
%, And one or more of Mo, W, and V are preferably contained in a total amount of 20% or less, and the composition is preferably composed of the balance of Fe and unavoidable impurities. C: 0.5 to 2.5% C is an element necessary to secure desired hardness.
In the present invention, the content is required to be 0.5% or more. C content
If it is less than 0.5%, the hardness of the compressor vane becomes low and the desired hardness cannot be obtained. On the other hand, if the content exceeds 2.5%, the material may be embrittled. Therefore, C is 0.
Preferably, it is limited to the range of 5 to 2.5%.

Si: not more than 2.5% Si is an element that acts as a deoxidizing agent and increases the hardness of the base structure. However, if it exceeds 2.5%, the material may be embrittled. For this reason, Si is preferably limited to 2.5% or less. In addition, more preferably 0.2 to 2.
0%. Mn: 1.0% or less Mn is an element that enhances the hardenability of the material, but if it exceeds 1.0%, the material may be embrittled. For this reason,
Mn is preferably limited to 1.0% or less. The content is more preferably 0.2 to 0.8%.

Ni: 0.6% or less Ni is an effective element for forming a solid solution in the matrix to strengthen the matrix and improve the hardenability, but the effect is saturated even if it exceeds 0.6%, The effect corresponding to the content cannot be expected. For this reason, Ni is preferably limited to 0.6% or less. It is more preferably 0.1 to 0.5%.

Cr: 3.0 to 20.0% Cr is an element which forms a solid solution in the matrix to strengthen the matrix and forms carbides to improve the wear resistance. Such an effect is not less than 3.0%. Is recognized. On the other hand, 20%
If it is contained in excess of, the grindability decreases. For this reason, Cr
Is preferably limited to 3.0 to 20.0%. The content is more preferably 4.0 to 18.0%.

20% or less in total of one or more of Mo, W, and V Mo, W, and V are elements that form carbides and improve wear resistance and scuff resistance. , Mo, W, and V may be selected and contained. Mo, W,
If one or more of V is contained in more than 20% in total, the opponent's aggressiveness is increased and it is economically disadvantageous. Therefore, it is preferable to limit one or more of Mo, W, and V to 20% or less in total.

The balance other than the above components is Fe and inevitable impurities. In addition, as inevitable impurities,
P: 0.04% or less, S: 0.03% or less is acceptable.

[0025]

EXAMPLE A flat plate-shaped compressor vane (4.2 mm thick × 24.1 mm wide × 24.1 mm long) having a spring seat having the shape shown in FIG. ) Was cast to near-net-shape by precision casting. A layered refractory coating was formed by alternately depositing slurry and stucco particles around a wax model made by injection molding using urea resin. Then, after drying and curing, the wax model was eluted, and then fired at a high temperature to obtain a mold. The molten metal having the composition shown in Table 1 was poured into the mold and solidified to form an as-cast vane. Some of these parts were further subjected to quenching and tempering (heat treatment QT: quenching at 1050 ° C., tempering at 550 ° C.) while as-cast, and only the tip part, which is the sliding part, was polished. Further, on some vanes, a nitride layer having a depth of 80 μm was formed on the surface layer by a gas nitriding method, or a CrN film having a thickness of 5 μm was formed by an ion plating method.

Further, the molten metal having the composition shown in Table 1 was formed into a plate-like cast piece, and this cast piece was formed into a curved shape at one end of the width (the tip of the vane) as shown in FIG. 3 (a). 4.2 x 24.1 x
It was forged into a 24.1 mm plate and pulled out. Next, these forged drawn plates are cut to have a predetermined vane width, a spring seat is formed by machining at the rear end, and the sliding surface is polished to obtain a product vane. And

The hardness (HRC) of these products was measured, and the products were assembled in an actual test machine having a structure as shown in FIG. Both the wear amount of the vane and the aggressiveness of the partner were evaluated by the wear ratio based on the conventional example (100). Further, the man-hour (working time × number of people) for manufacturing the vane was calculated, and the productivity (cost ratio) of the example of the present invention was evaluated using the man-hour of the comparative example as a reference (100).

Table 2 shows the results.

[0029]

[Table 1]

[0030]

[Table 2]

The abrasion resistance of the example of the present invention is remarkably improved without any surface treatment as compared with the conventional example. Further, in the example of the present invention, the productivity is remarkably improved as compared with the conventional example. Among the examples of the present invention, the example of the present invention in which the CrN film was not formed on the sliding surface surface had a slightly lower abrasion resistance than the example in which the CrN film was formed on the sliding surface surface, and the vane replacement time was slightly longer. It became shorter.

[0032]

As described above, according to the present invention,
Efficiently manufacture compressor vanes with excellent wear resistance.
It has a remarkable industrial effect.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of the shape of a compressor vane.

FIG. 2 is a schematic configuration diagram showing a rolling compressor to which the compressor vane of the present invention can be applied.

FIG. 3 is an explanatory view showing an example of a conventional method for processing a compressor vane.

FIG. 4 is a sectional view showing an example of a spring seat shape suitable for the compressor vane of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Compressor 2 Rotating shaft 3 Cylinder 4 Eccentric part 5 Roller 6 Vane 7 Spring 8 Cylinder groove 9 Spring seat 10 Projection

Claims (2)

[Claims] 1. A compressor is inserted into a groove formed in a radial direction of a compressor cylinder, a spring is engaged with a rear end portion, and a front end portion is brought into contact with an outer peripheral surface of a roller disposed in the cylinder.
A sliding compressor vane, having a flat plate shape having a curved surface or an R-shaped front end, and having a spring seat for engaging the spring at the rear end, formed by precision casting, A vane for a compressor, which is polished. 2. The compressor vane according to claim 1, wherein:
0.5 to 2.5%, Si: 2.5% or less, Mn: 1.0% or less, Ni:
0.6% or less, Cr: 3.0 to 20.0%, Mo, W,
2. A vane for a compressor according to claim 1, wherein the vane is a precision cast material containing 20% or less in total of one or more of V and having a balance of Fe and unavoidable impurities. .