CN101040117A - sliding device - Google Patents

Abstract

The sliding device (1) is composed of a swash plate (3) having a first sliding surface (3A) and a hemispherical shoe (4) sliding with the swash plate (3). The swash plate (3) is formed of a base material (3B) of high-strength brass containing Mn and Si, and fine particles of Mn-Si are exposed inside the base material (3B) and on the first sliding surface (3A). Compound (6). The above-mentioned swash plate (3) increases the exposure amount of the Mn-Si compound (6) exposed on the first sliding surface (3A) as the surface by cutting the base material (3B) and then etching. In addition, the shoe (4) is made of an iron material, and fine unevenness (4a, 4b) is formed on the second sliding surface (4A) of the shoe (4) by laser quenching. Since many Mn-Si compounds (6) are exposed on the first sliding surface (3A) of the swash plate (3) in the form of particles, there are small spaces that are continuous with each other at the positions adjacent to them, which serve as the lubricating oil. Since the circulation channel functions, the wettability of the lubricating oil to the first sliding surface (3A) becomes good, and the seizure resistance becomes good. And, since laser hardening is performed on the second sliding surface (4A) of the shoe (4) to form many minute unevenness (4a, 4b), therefore, the second sliding surface (4A) of the shoe (4) can be improved. The load capacity and wear resistance become better.

Description

sliding device

technical field

The present invention relates to a sliding device, and more particularly to a sliding device composed of a swash plate and a shoe sliding thereon.

Background technique

At present, the following device is known as a sliding device for a swash plate type compressor, which has a swash plate and a shoe, the swash plate forms a flat first sliding surface on at least one end surface of the swash plate; A flat second sliding surface on which the first sliding surface slides (for example, Patent Document 1, Patent Document 2).

Patent Document 1: Japanese Patent Application Laid-Open No. 10-153169

Patent Document 2: Japanese Patent Laid-Open No. 2002-317757

Contents of the invention

However, the above-mentioned conventional swash plate type compressors have recently been used under high-speed, high-load conditions, and under conditions with a small amount of lubricating oil. In this way, since the operating conditions of the sliding device have become increasingly severe recently, the wear of the swash plate and the shoe is severe, and sintering tends to occur.

In addition, the above-mentioned swash plate currently available uses high-strength brass as a material. Although the swash plate using such high-strength brass is low in manufacturing cost, it has the disadvantage of poor sintering resistance.

In view of the above circumstances, the present invention provides a sliding device, which has a swash plate and a shoe, the swash plate forms a flat first sliding surface on at least one end surface; a flat second sliding surface; the swash plate has a base material formed of high-strength brass containing Mn and Si, and the Mn-Si compound is exposed on the surface of the base material that becomes the first sliding surface; the sliding shoe It is made of iron-based material, and the second sliding surface of the shoe is laser hardened to form minute unevenness.

According to such a configuration, as is apparent from test results described later, it is possible to provide a sliding device having better seizing resistance and lower manufacturing costs than those in the prior art.

Description of drawings

Fig. 1 is a cross-sectional view showing an essential part of an embodiment of the present invention.

FIG. 2 is an enlarged view of the first sliding surface 3A of the swash plate shown in FIG. 1 .

Fig. 3 is a cross-sectional view along line III-III of Fig. 2 .

Fig. 4 is a view showing an enlarged photograph of the first sliding surface of the swash plate subjected to only cutting.

Fig. 5 is a view showing an enlarged photograph of the first sliding surface of the swash plate of the present embodiment shown in Fig. 2 .

Fig. 6 is a diagram showing test results of seizing resistance of the present embodiment shown in Fig. 1 and the conventional art.

FIG. 7 is a front view showing the second sliding surface 4A of the shoe 4 .

8 is a cross-sectional view of main parts along line VIII-VIII in FIG. 7 .

Fig. 9 is a sectional view of main parts of a swash plate according to a second embodiment of the present invention.

Fig. 10 is a graph showing test results of seizing resistance of the second embodiment shown in Fig. 9 and the prior art.

Fig. 11 is a front view showing a second sliding surface of another embodiment of the shoe.

Fig. 12 is a front view showing a second sliding surface of still another embodiment of the shoe.

Fig. 13 is a front view showing a second sliding surface of still another embodiment of the shoe.

Detailed ways

Hereinafter, the present invention will be described according to the illustrated embodiment. In FIG. 1 , the sliding device 1 is arranged in the housing of the swash plate compressor. The sliding device 1 is composed of a swash plate 3 obliquely attached to the rotary shaft 2 and a plurality of shoes 4 sliding on the swash plate 3 . The rotating shaft 2 is supported in the above-mentioned housing via a shaft.

The swash plate 3 is formed in a disc shape, and both end surfaces of the swash plate 3 serve as flat first sliding surfaces 3A, 3A that slide with the shoe 4 .

On the other hand, the shoe 4 has a hemispherical shape as a whole and is composed of a flat second sliding surface 4A sliding on the first sliding surface 3A of the swash plate 3 and a hemispherical convex surface 4B forming a hemispherical shape.

In the casing of the swash plate type compressor, a plurality of pistons 5 are provided parallel to the rotation shaft 2 and surrounding the rotation shaft 2 . A set of two shoes 4 is slidably held in an arc-shaped notch 5A formed at one end of each piston 5 so that the notch 5A in this state wraps around the outer periphery of the swash plate 3 . In addition, the second sliding surfaces 4A of the shoes 4 of each group are brought into contact with the first sliding surfaces 3A of the swash plate 3 .

And, when the above-mentioned rotating shaft 2 rotates, the swash plate 3 rotates, and the first sliding surface 3A, which is both ends of the swash plate 3, slides with the second sliding surface 4A of each set of shoes 4, and accordingly, each piston 5 passes through. Each set of shoes 4 moves forward and backward in the axial direction.

The above-mentioned constitution is the same as the prior known sliding device.

However, in this embodiment, the following improvements are made to the sliding device 1 composed of the above-mentioned swash plate 3 and the sliding shoe 4, so that the anti-seizing property of the sliding device 1 is improved.

That is, the swash plate 3 of this embodiment is composed of a base material made of high-strength brass containing 2 to 3.5% by mass of Mn and 0.5 to 1.5% by mass of Si.

In this embodiment, first, the base material 3B made of the above-mentioned high-strength brass is formed into a disk shape by cutting, and then the entire first sliding surface 3A is etched to complete the processing.

As shown in FIGS. 2 to 3 , hard, fine-grained Mn—Si compound 6 is exposed both inside the base material 3B and on the first sliding surface 3A as the surface. In addition, in this embodiment, after cutting as described above, the entire first sliding surface 3A is etched to increase the granular particles exposed on the first sliding surface 3A as the surface of the base material 3B. Exposure amount of Mn-Si compound 6.

The inventors of the present application have studied and found that the Mn-Si compound 6 is exposed on the surfaces of the first sliding surface 3A and the base material 3B even if the first sliding surface 3A is not subjected to etching treatment. The exposed amount of the Mn—Si compound 6 on the surface of the base material 3B, that is, on the first sliding surface 3A increases. Therefore, in this embodiment, the etching treatment is performed on the surface of the base material 3B after cutting, that is, the first sliding surface 3A.

The etching treatment is performed by immersing the cut base material to become the swash plate 3 in an etching solution containing sulfuric acid and hydrogen peroxide.

FIG. 4 is an enlarged photograph of the first sliding surface 3A (surface) that is the surface of the base material 3B when only cutting is performed and no etching treatment is performed. In this FIG. 4 , minute black dots represent granular Mn—Si compounds 6 . As shown in FIG. 4 , in the case where only cutting and no etching treatment is performed, the Mn- The area ratio of Si compound 6 was 1.7%, and the average diameter of exposed Mn—Si compound 6 particles was 4.6 μm.

In addition, since the Mn-Si compound 6 is completely exposed with respect to the above-mentioned entire first sliding surface 3A, 1.7% of the Mn-Si compound 6 exposed on the first sliding surface 3A in the range shown in FIG. The area ratio can be considered substantially as the ratio of the exposed area of the Mn—Si compound 6 to the entire first sliding surface 3A. This is also the same in the above-described embodiment in which the etching treatment is performed on the first sliding surface 3A.

On the other hand, as shown in FIG. 5 , in the embodiment in which the etching treatment was performed on the first sliding surface 3A of the base material 3B after the above-mentioned cutting process, the surface exposed on the first sliding surface 3A (the base material 3B) The exposed amount of the granular Mn-Si compound 6 on the surface of the surface) is significantly increased compared with the above-mentioned FIG. 4 . In this example shown in FIG. 5 , the area ratio of the Mn—Si compound 6 exposed on the first sliding surface 3A is 6.6%, and the average diameter of the exposed Mn—Si compound 6 particles is 5.6 μm.

Thus, in this embodiment, the Mn—Si compound 6 exposed on the first sliding surface 3A is increased by performing etching on the first sliding surface 3A of the base material 3B after cutting. In this way, many fine protrusions are formed from the Mn—Si compound 6 particles all over the first sliding surface 3A, and fine spaces that are continuous with each other are formed at positions adjacent to these particles.

In addition, by etching the first sliding surface 3A of the swash plate 3 after cutting, it is possible to remove minute burrs or damages generated on the first sliding surface 3A during cutting.

Moreover, in the case of performing machining such as cutting and grinding on the above-mentioned first sliding surface 3A, if the ratio of the Mn-Si compound 6 exposed on the first sliding surface 3A is to be increased, the first sliding surface The roughness of 3A is also reduced. In this way, the first sliding surface 3A serves to keep the lubricating oil from deteriorating wettability.

However, in the case of this embodiment in which etching is performed after cutting the first sliding surface 3A, the Mn-Si compound can be increased as described above without making the roughness of the first sliding surface 3A too small. 6, the wettability of the first sliding surface 3A is also good.

On the other hand, the shoe 4 of this embodiment is formed of SUJ2 which is a ferrous material. As shown in FIG. The other portions are oppositely formed as recessed portions 4b, and a concavo-convex surface is formed on the second sliding surface 4A.

The said convex part 4a is formed by irradiating laser light to the said 2nd sliding surface 4A, and quenching the 2nd sliding surface 4A directly by this irradiation. That is, as shown in FIG. 8 , the irradiated portion of the above-mentioned laser irradiation is in a state where the base material surface 4c forming the original surface of the second sliding surface 4A is directly quenched, and bulges out from the base material surface 4c, thus forming the convex portion 4a. .

Thus, although the laser irradiated portion is directly quenched, the concave portion 4b adjacent to the laser irradiated portion and not irradiated with the laser is not directly quenched, and this portion becomes an indirect quenched portion. And this indirect quenching part is recessed relatively with respect to the said convex part 4a, and forms the recessed part 4b.

However, the recessed portion 4b, which is an indirect quenching portion, is not unquenched. That is, the quenching range formed by laser irradiation is, for example, shown by dotted line 7 in FIG. Quenching can also be performed on the concave portion 4b. Whether or not to quench the portion of the concave portion 4 b that is the non-direct quenching portion can be set according to the irradiation interval of the laser light. In addition, if quenching is performed on the recessed portion 4b, which is the non-directly quenched portion, this portion does not protrude like the protruding portion 4a, but it also protrudes from the surface 4c of the base material.

In this example, after the second sliding surface 4A of the shoe 4 made of SUJ2 is irradiated in parallel at intervals of 0.2 mm in a straight line, the YAG laser is also irradiated in parallel at intervals of 0.2 mm in a direction perpendicular thereto. The YAG laser is irradiated to the whole body in a grid pattern. The interval is preferably in the range of 0.1 to 0.3 mm.

The output of the above-mentioned YAG laser is 50W, and the condenser lens is adjusted so that the above-mentioned YAG laser is focused on the surface of the second sliding surface 4A at a position of deep 2mm. The state is irradiated with YAG laser.

The surface hardness of the convex part 4a of the directly quenched part after the laser irradiation is increased by about Hv100 compared with the hardness Hv750 of the base material, and the surface hardness of the concave part 4b is increased by about Hv50. On the other hand, the part 8 (refer to FIG. 8 ), which is slightly deeper than the direct quenching part, is annealed and has a hardness about Hv100 lower than that of the base material, and the intersection point of the convex part 4a and the convex part 4a of the direct quenching part, that is, the laser The part where the irradiated part intersects is also annealed, and the hardness is about Hv100 lower than that of the base metal. However, since quenching by laser is rapid cooling, no decrease in the hardness of the base material was confirmed at a position deeper than the above-mentioned slightly deeper portion 6 .

In this embodiment, after irradiating the laser beam to the second sliding surface 4A as described above, grinding and buffing are sequentially performed to complete the process. Furthermore, the height of the convex portion 4a relative to the above-mentioned concave portion 4b is about 0.1 to 10 μm immediately after laser processing, and is preferably in the range of 0.1 to 1 μm in the finished product after grinding and polishing.

In addition, in this embodiment, SUJ2 was used as the material of the shoe, but it is not limited thereto, and other iron-based materials may of course be used.

FIG. 6 is a graph showing the seizure resistance of the sliding device 1 of the present embodiment composed of the swash plate 3 and the shoe 4 formed as described above and a sliding device having a conventional general swash plate (prior art). test results. In addition, the test conditions are as follows.

Inclined plate rotation speed: 9000rpm (increase the rotation speed by 1000rpm x 1 minute each time, divided into 9 times)

Surface pressure: preload 2.7MPa, increase b2.7MPa per minute until sintering

Oil mist amount: 0.05g/min

Oil: refrigeration oil

Sintering conditions: shaft torque max.4.0N m

In addition, in the prior art shown in FIG. 6 , the swash plate is a swash plate obtained by cutting conventional high-strength brass, and the shoe has the same structure as the above-mentioned present embodiment.

It can be seen from Fig. 6 that the sintering loads of the sliding devices of the prior art using the existing swash plate are all below 5 MPa. However, the sintering load of the sliding device 1 of this embodiment is all above 15 MPa, and it can be seen that it has very good sintering resistance.

Thus, the reason why the sliding device 1 of this embodiment has very good seizure resistance is as follows.

That is, on the first sliding surface 3A of the swash plate 3, many Mn-Si compounds in a granular state are exposed, and these Mn-Si compounds form a state slightly protruding from the surface of the original base material 3B (refer to FIGS. 3). Therefore, when the second sliding surface 4A of the shoe 4 as a mating member slides with the first sliding surface 3A of the swash plate 3 , the first sliding surface 4A of the shoe 4 acts on the first sliding surface of the swash plate 3 . The surface pressure of 3A is relieved by the support of many Mn-Si compounds 6 . Therefore, the surface pressure exerted by the shoe 4 on the first sliding surface 3A of the swash plate 3 can be reduced compared to using a conventional general swash plate.

And, in the present embodiment, since many Mn-Si compounds 6 are exposed on the first sliding surface 3A of the swash plate 3 in a granular state, there are small space portions continuous with each other at positions adjacent thereto. This functions as a circulation path for lubricating oil.

In addition, in the case of the present embodiment in which the first sliding surface 3A is cut and then etched, the roughness of the first sliding surface 3A is not reduced too much and the exposed amount of the Mn—Si compound 6 is not increased. Therefore, the wettability of the lubricating oil to the first sliding surface 3A also becomes good.

For this reason, the sliding device 1 of the present embodiment has very good seizure resistance as described above.

As described above, according to the present embodiment, since inexpensive high-strength brass is used for the swash plate 3 , it is possible to provide the sliding device 1 with low manufacturing cost and good seizure resistance.

In addition, by performing etching treatment on the first sliding surface 3A after cutting, it is possible to remove minute burrs and damages generated on the first sliding surface 3A during cutting. Therefore, it is possible to omit such an operation process for removing burrs and the like, and accordingly, the manufacturing cost of the slide device 1 can be reduced.

Moreover, since laser quenching is performed on the second sliding surface 4A of the shoe 4 of the present embodiment to form many minute unevennesses, the load capacity of the second sliding surface 4A of the shoe 4 can be increased, thereby providing wear resistance. Highly destructive sliding device 1.

Fig. 9 is a cross-sectional view showing the swash plate 3 of the sliding device 1 according to the second embodiment of the present invention. On the swash plate 3 of the sliding device 1 of the above-mentioned first embodiment, the first sliding surface 3A of the swash plate 3 is not subjected to surface treatment, but in this second embodiment, the slant plate 3 of the first embodiment above is used. On the premise of the structure of the plate 3, Sn plating with a thickness of 0.3 to 3 μm is performed on the entire first sliding surface 3A. Other configurations of the second embodiment are the same as those of the sliding device 1 of the first embodiment, and their descriptions are omitted.

Next, the test results of the seizing resistance of the sliding device 1 of the second example and the prior art 1 and 2 are shown with FIG. 10 . In prior art 1, the swash plate is made of a high-strength brass material containing Mn and Si, and the shoe is made of SUJ2 which has not been laser-hardened. Also, in prior art 2, the swash plate is made of a high-strength brass material containing Mn and Si, and the sliding surface is plated with Sn as in the present embodiment, and the shoe is made of SUJ2 which has not been laser-hardened.

In addition, the test conditions are as follows, and each of the prior art 1, 2 and the present example was tested twice. The left side of each test subject is the result of the first test, and the right side is the result of the second test.

(Test conditions)

Inclined plate speed: increase 1000rpm per minute, increase 9 times: maximum speed 9000rpm (circumferential speed 38m/s)

Surface pressure: preload 2.7MPa Increase 2.7MPa per minute: until sintering

Oil mist volume: 0.05～0.25g/min The nozzle position is fixed

Oil: refrigeration oil

Sintering conditions: Shaft torque over 4.0N·m

That is, the rotation speed of the swash plate is increased under the above-mentioned conditions while the end surface of the shoe is in pressure contact with the swash plate. On the other hand, under the above conditions, when the surface pressure is increased when the shoe is pressed against the swash plate and the axial torque applied to the swash plate exceeds 4.0 N·m, it is judged that sintering has been achieved. The conventional techniques 1 and 2 are the same in this point.

From the test results shown in FIG. 10, it can be understood that the sintering load of the sliding device of the prior art 1 and 2 is 8.1 MPa or less, while the sintering load of the sliding device 1 of the second embodiment is 13.5 MPa or 16.2 MPa. The sliding device 1 of the second embodiment has significantly better anti-sintering properties than the conventional ones, and can obtain the same functions and effects as those of the above-mentioned first embodiment.

Also, in this second embodiment, since the first sliding surface 3A of the swash plate 3 at the beginning of use is formed of Sn3C plating, the first sliding surface 3A of the swash plate 3 and the second sliding surface of the shoe 4 can be improved. 4A running-in.

In addition, in the second embodiment shown in FIG. 9 , Sn is plated on the entire first sliding surface 3A of the swash plate 3 as a surface treatment. In addition to this method, alloy solder plating and resin coating can also be used. any type.

11 to 12 show another embodiment in the case of performing laser hardening on the shoe 4 . That is, in FIG. 11 , when the second sliding surface 4A of the shoe 4 is laser hardened, the laser beam is irradiated to the second sliding surface 4A along a movement trajectory forming parallel lines at equal intervals to form convex portions 4a and concave portions 4b.

12 , with respect to the second sliding surface 4A of the shoe 4 , a plurality of concentric circles are formed around the center, and the second sliding surface 4A is irradiated with laser light for quenching. In this example, the convex portion 4a is also formed at the irradiation position of the laser light, and at the same time, the concave portion 4b is formed at the adjacent position.

Moreover, FIG. 13 shows still another example in the case of laser hardening the shoe 4 . In the embodiment shown in FIG. 13 , laser light is irradiated to the entire second sliding surface 4A of the shoe 4 so that a plurality of circles are arranged in a zigzag shape. In this way, the position of each circle irradiated with the laser light becomes the convex portion 4a, and the inner and outer portions thereof become the concave portion 4b.

Claims (6)

1. a sliding device has swash plate and piston shoes, and swash plate is at least at the first smooth slip surface of a square one-tenth of end face; Piston shoes have the second smooth slip surface that first slip surface with above-mentioned swash plate slides,

It is characterized in that above-mentioned swash plate has the mother metal that is formed by the high strength brass that contains Mn and Si, and the Mn-Si compound is exposed on the surface of above-mentioned first slip surface of becoming of this mother metal;

Above-mentioned piston shoes are formed by iron type materials, and form small concavo-convex on second slip surface of piston shoes by laser hardening.

2. sliding device as claimed in claim 1 is characterized in that, on the mother metal surface of above-mentioned swash plate, by removing this mother metal the amount of exposing as the lip-deep Mn-Si compound of above-mentioned first slip surface of exposing is increased.

3. sliding device as claimed in claim 1 or 2 is characterized in that, plates any surface treatment in Sn, alloy plating scolder, the application of resin on whole first slip surface that above-mentioned Mn-Si compound is exposed.

4. as each described sliding device in the claim 1 to 3, it is characterized in that the mother metal of above-mentioned swash plate is the high strength brass that contains the Si of the Mn of 2～3.5 quality % and 0.5～1.5 quality %.

5. as each described sliding device in the claim 1 to 4, it is characterized in that the laser hardening of second slip surface of above-mentioned piston shoes is implemented to the above-mentioned second slip surface irradiating laser to form trellis, parallel straight line shape or the motion track of concentric circles.

6. as each described sliding device in the claim 1 to 5, it is characterized in that, above-mentioned Mn-Si compound is granular ground and exposes on first slip surface of above-mentioned swash plate, the average diameter of this granular Mn-Si compound is 3～10 μ m, and the Mn-Si compound is 3～15% with respect to the area ratio that the area of first slip surface exposes.

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