JP4846670B2 - Fluorine resin coating method, sliding member using the method, and gas compressor - Google Patents

Description

  The present invention relates to a fluorine resin coating method, a sliding member using the method, and a gas compressor.

  In general, wear resistance and seizure resistance are required on sliding surfaces between members sliding with each other. On the other hand, there are many cases where there is a strong demand for weight reduction of its constituent members, such as an in-vehicle gas compressor. In such a case, a lightweight material such as an aluminum alloy is used as the member.

  Aluminum alloy, etc. is lightweight, but when sliding against each other, it is inferior in wear resistance and seizure resistance. Therefore, a sliding surface of one member is coated with a fluorine-based resin such as polytetrafluoroethylene. Sometimes. In this way, poor lubrication, wear and seizure due to sliding between the same kind of metals are avoided.

  In this fluororesin coating, strong adhesion between the aluminum alloy or the like and the fluororesin coating layer is required so that peeling of the fluororesin coating layer of the base material due to sliding does not occur. Conventionally, various inventions have been made to improve adhesion.

  As an invention for making the coating layer itself a layer that easily adheres to an aluminum alloy or the like, for example, a coating layer of a fluororesin and a binder is applied to the surface of an Al alloy piston in a swash plate compressor, and the binder is coated with an Al alloy. An invention for firmly adhering a layer is known (for example, see Patent Document 1).

JP 2000-170657 A (paragraph number 0020, FIG. 2)

  As an invention for improving the adhesion by roughening the coating base of aluminum alloy or the like, etching (see Patent Document 2 and Patent Document 3) is added, and etching and coating layer itself are further improved. The thing (for example, refer patent document 4) is known.

JP-A-5-209300 (Claims)

JP-A-6-65799 (paragraph numbers 0014 to 0018, FIG. 3)

JP-A-5-84468 (paragraph number 0008, FIG. 2)

  Although these adhesion improving techniques exhibit a certain effect, they cannot be said to be sufficient for application to a sliding surface that slides under a severe load.

  As an invention for improving the adhesion by roughening a coating base such as an aluminum alloy, one based on shot blasting is known (for example, see Patent Document 5).

JP 2001-263226 A (paragraph numbers 0038 to 0040)

  The fluororesin coating for roughening by shot blasting is generally performed in the process shown in FIG.

  In FIG. 15, in the base treatment process, first, a base material such as an aluminum alloy is cleaned (first cleaning 801), and the cleaned base material is made of fine and high hardness aluminum oxide having a particle diameter of several tens of μm. The shot material is shot blasted (802) to roughen and clean the surface. By this roughening and cleaning, the adhesion between the base material and the fluororesin coating layer is improved.

  Next, the shot material is dropped (sand removal 803), washed (second washing 804), then subjected to a chemical conversion treatment on the roughened and cleaned surface to prevent oxidation (805), and then After cleaning (third cleaning 806), fluororesin coating is performed (807) and baked (808) to complete the coating of the fluororesin on the base material.

  In shot blasting, the shot material strikes the surface of the base material to form fine irregularities, and the fluorine-based resin enters the fine depressions to significantly improve the adhesion.

  By the way, the shot material used for the shot blasting may go deep into the minute gaps of the base material during the shot blasting (802), and cannot be removed even in the subsequent sand removal step (803) and the second cleaning step (804). is there. When the base material is a cast product, there are many minute gaps, and in particular, the shot material tends to remain.

  The high hardness shot material remaining on the fluororesin-coated base material is used by being incorporated into a product such as a gas compressor.

  During use of the product, the remaining shot material is detached from the base material due to its operation (rotation of the rotor, jet of fluid inside, etc.). The detached high-hardness shot material enters the sliding portion of the product, damages the coating layer and the metal portion of the sliding portion, and eventually causes seizure, making the operation impossible.

As described above, in the conventional fluorine-based resin coating technology for a base material such as an aluminum alloy, the coating layer is easily peeled off due to long-term use. This peeling of the coating layer tends to occur particularly when the maximum load is large and the load fluctuation cycle is large, or when the lubrication state at the start-up is not good. For example, the sliding surfaces of the rotor, cylinder, side block, and vane of the vane type gas compressor are likely to be peeled off.

  The present invention has been made to solve the above-mentioned problems, and the object of the present invention is to provide a high-quality fluororesin coating method having excellent adhesion as described below and a sliding member using this method. It is intended to provide a gas compressor.

(1) No peeling occurs even under sliding under severe load conditions.
(2) The shot material used during the coating base treatment does not remain on the base material such as an aluminum alloy in the vicinity of the coating layer, and there is no possibility that the remaining shot material damages the coating layer or the like.

To achieve the above object, the present invention method of claim 1, mother and plasma irradiation step of roughening the surface of the base material of the coating object by the plasma irradiation, the coating object which is roughened by the plasma irradiation A fluororesin coating process in which the surface of the material is coated with a fluororesin, and a firing process in which the coated surface of the coating object coated with the fluororesin in the fluororesin coating process is fired.

The invention method of claim 2 is characterized in that in claim 1 , a roughening / cleaning treatment step of roughening / cleaning the surface of the object to be coated is added before the plasma irradiation step, thereby strengthening fluorine. A resin coating is obtained.

The invention method of claim 3 or 4 is the method according to claim 2, wherein the surface of the coating object is shot blasted with a water-soluble shot material or a vaporizable shot material, or the object to be coated as the roughening / cleaning treatment step. The surface of the object is irradiated with a laser.

The invention of claim 5 , 6 or 7 is applied to the sliding member, in particular, the sliding member of the gas compressor, as a coating object, and the coating process of the above-described invention method is applied, and the peeling resistance and abrasion resistance of the sliding part are applied. A highly reliable sliding member and gas compressor excellent in wear and durability can be obtained.

  In the present invention, the “irradiation rate of laser irradiation” means the rate of the dot area where the laser is actually irradiated with respect to the irradiation target area. For example, as shown in FIG. 3A, when irradiation is performed so that the irradiation dots R are arranged in a square shape with an equal pitch p in the front, rear, left, and right directions with respect to the irradiation target surface, In this case, there are four quarters of the irradiation dots, and the irradiation rate = S / U.

According to the method of the present invention, in the base treatment process of the surface of the base material to be coated, the surface of the coating object is irradiated with plasma to clean the surface, and the surface is finely roughened at the atomic level. Fluorine resin coating was applied to the surface with improved adhesion and adhesion. Therefore, the fluororesin coating is difficult to peel off, and the shot material does not remain on the base material in the vicinity of the fluororesin coating layer. When the residual shot material rubs against other members, it moves to the coating layer and the base material. There is no risk of damaging the material. In addition to this, chemical conversion treatment, which has been essential in the past, is no longer necessary, and it is no longer necessary to install wastewater treatment equipment for treating harmful wastewater generated during chemical conversion treatment. Therefore, significant cost reduction is realized, and there is no risk of environmental pollution due to waste water leakage. The plasma irradiation process can be incorporated into the fluororesin coating process, and the production efficiency is greatly improved.

A gas compressor having a sliding member whose sliding surface is coated with a fluorine-based resin and a sliding member whose sliding surface is coated with a fluorine-based resin by the above-described coating method has a long life and improved reliability.

  Embodiments of the present invention will be described below with reference to FIGS.

FIG. 1 shows a processing flow of a fluororesin coating method (one reference example for explaining the present invention) .

  In FIG. 1, a fluorine-based resin coating is performed on a surface that becomes a sliding surface of an aluminum alloy base material that becomes a side block of an in-vehicle gas compressor.

First, the entire base material of the aluminum alloy is cleaned (first cleaning 101). The surface to be the sliding surface of the cleaned base material is shot blasted with a sodium bicarbonate NaHCO ₃ shot material to roughen and clean the surface (102). This sodium bicarbonate shot material has a lower hardness than aluminum oxide, but is water soluble.

  Accordingly, in the next second cleaning step 103, the shot material is dissolved in the cleaning liquid, and the shot material that has entered the gap between the base materials also flows out and is completely discharged to the outside. As in the past, the “sand removal” process is unnecessary.

  The base material whose surface has been roughened and cleaned, and from which the shot material has been completely removed, is subjected to chemical conversion treatment (104) for prevention of oxidation, etc., third cleaning (105), fluororesin in the usual manner. Through the steps of painting (106) and baking (107), a fluororesin coating is completed.

  In this way, since there is no residual shot material, the shot material does not flow out during the operation of the gas compressor and damage the sliding part, etc., the gas compressor increases durability and has a long life, Reliability is improved.

As a water-soluble shot material, calcium bicarbonate Ca ₃ (PO ₄ ) ₂ or the like can be used in addition to sodium bicarbonate NaHCO ₃ . Further, since it is sufficient if there is no residual shot material, a vaporizable shot material, for example, a fine granular dry ice CO ₂ shot material can be used.

FIG. 2 shows a processing flow of a fluorine resin coating method (another reference example for explaining the present invention) .

  FIG. 2 is the same as FIG. 1 except that a laser irradiation process 202 is entered instead of the shot blasting process 102.

  In the laser irradiation step 202, as in the shot blasting step 102 of FIG. 1, the surface that becomes the sliding surface of the base material is roughened and cleaned to improve the adhesion and adhesion to the fluororesin. Since no shot material is used, there is of course no residual shot material.

  The intensity of the laser beam used in the laser irradiation step 202 is such that the surface of the base material is slightly melted and roughened, and a shallow recess (irradiation dot) R having a diameter d is two-dimensional as shown in FIG. They were formed so as to be lined up at substantially equal pitch p in the direction. More specifically, the method of forming the arrangement of the recesses R will be described. As shown in FIGS. 3B and 3C, the side block 7 of the gas compressor is rotated around its center C as indicated by an arrow A. Then, the laser beam is moved in the radial direction B of the side block 7. In order for the laser beam to scan the surface of the side block 7 around the center C in a spiral shape with an equal pitch, the rotational speed of the side block 7 is set so that the peripheral speed of this spiral scan is substantially constant. In addition to the control, the moving speed of the laser beam is controlled so as to increase as it approaches the center C. On the other hand, the laser beam is controlled to blink at a predetermined oscillation frequency by Q switching, and the side block surface is locally heated and melted to be roughened to form and form the recesses R as shown in FIG.

Figure 3 In the case of (a), the irradiation of the laser irradiation, the irradiation dot area ^{S (= πd 2/4)} / unit irradiation area U (= ^{p 2).}

  There are various other methods for forming the recesses R. For example, the laser beam is rotated in a spiral shape while the side block 7 is stationary, and the peripheral speed of the spiral rotation is made constant. The blinking frequency of the laser light may be changed while rotating the side block 7 or the laser light at a constant speed. In addition, the diameter (dot diameter) d and pitch (dot interval) p of the recesses R may be appropriately selected within the range where roughening and cleaning are performed, and it is not always necessary to have a uniform distribution over the entire surface.

  For example, as shown in FIG. 4, the irradiation dots R may be arranged in a staggered manner. In the example of FIG. 4, the irradiation rate of laser irradiation is increased by efficiently irradiating while avoiding twice irradiation at the same location so that the dots arranged in a staggered manner do not touch and overlap each other. Incidentally, the irradiation rate when d = p when irradiated with the pattern shown in FIG. 3A is about 78.5%, and the irradiation rate when d = p when irradiated with the pattern shown in FIG. Is about 90.7%.

  The relationship between the irradiation rate of laser irradiation and the adhesion and adhesion between the base material and the fluororesin has been confirmed by experiments. When the irradiation rate is set to 44% or more, the adhesion and adhesion are improved. It was concluded that it can withstand sliding friction under load and has excellent durability. Hereinafter, this experiment will be described with reference to FIGS.

  FIG. 5 is an explanatory diagram for explaining an outline of a test apparatus used for the durability test of the adhesion surface between the base material and the fluororesin. FIG. 6 is an explanatory diagram in which the test results of the aluminum flat member with a fluorine-based resin coating used in the test are plotted on a graph in which the horizontal axis represents the laser irradiation dot diameter and the vertical axis represents the dot interval. Note that FIG. 6 shows the irradiation with the pattern of FIG. 3A, and the irradiation rate (irradiation density) of laser irradiation is calculated from the dot diameter and the dot interval. FIG. 7 is an explanatory diagram in which FIG. 6 is plotted by taking the dot area on the horizontal axis and the unit irradiation target area on the vertical axis, and FIG. 8 is an explanatory diagram showing the relationship between the laser output and the dot diameter.

  An aluminum flat member T1 with a fluorine resin coating was manufactured by the fluorine resin coating method including the laser irradiation step shown in FIG. 2, and tested with the test apparatus shown in FIG. As shown in FIG. 5, the aluminum flat member T <b> 2 having no coating is brought into opposed contact with the lubricating oil. A load L was applied in a direction perpendicular to the contact surface, and the aluminum flat member T2 was rotated and slid while increasing the load stepwise to test whether the coating was peeled off or seized.

  Aluminum flat member T1 with a fluorine-based resin coating (diameter 50 mm, coating thickness 15 μm) was manufactured as a test member shown in Table 1 by individually changing the laser irradiation conditions. All test members were manufactured under the same conditions except for the laser irradiation conditions.

  The inventions and comparative products in Table 1 were subjected to a durability test under the following test conditions.

Additional load and time: 5 minutes with 500N, then + 500N, that is, 5 minutes with 1000N,...
Rotation speed: 4000rpm
In the test under these conditions, neither the invention product nor the comparative product was seized. After the test up to 5000 N for 5 min, observe the fluororesin coating surface and examine the amount of peeling of the coating. If the amount of peeling is less than the current side block by shot blasting, OK (◯), if more, NG ( X).

  The determination results are plotted in FIG. 6 and FIG. As can be understood from FIGS. 6 and 7, if the invention has an irradiation density (irradiation rate) of 44% or more, the adhesiveness and adhesiveness of the fluororesin coating layer are strong and the durability is excellent. In the comparative product of less than 44%, the durability was not improved.

  By the way, as shown in FIG. 6 and FIG. 7, when the irradiation density (irradiation rate) is set to 44% or more when laser irradiation is performed so as to form a square arrangement at equal pitch p in the front, rear, left, and right, the dot diameter d and The relationship with the dot interval p must be p ≦ 1.336 × d. Also, in order to increase the irradiation density (irradiation rate) to 44% or more when irradiating in a triangular arrangement with a staggered equal pitch p as shown in FIG. 4, the dot diameter d and the dot interval p The relationship must be p ≦ 1.436 × d. To increase the dot diameter d, it is necessary to increase the laser output as shown in FIG.

  Therefore, in the above invention products 1 to 9 and 11, a YAG laser was used. YAG laser can increase the output, has a relatively large area such as the sliding surface of the side block, roughening the surface of the fluororesin coating on the sliding surface used under severe sliding conditions with large load fluctuation and maximum load It is suitable for performing the laser irradiation efficiently.

  In the second embodiment using laser irradiation, there is an advantage that the rough surface state can be easily matched to the target state as compared with the first embodiment using shot blasting. In particular, when the irradiation density (irradiation rate) of laser irradiation is set to 44% or more, the adhesiveness is improved and it can be applied to a sliding member under severe use conditions.

FIG. 9 shows a processing flow of the first embodiment of the fluororesin coating method of the present invention.

In FIG. 9, as in FIG. 1, a first cleaning step 101, a shot blasting step (102) in which shot blasting is performed with a shot material of sodium bicarbonate NaHCO ₃ to roughen and clean the surface, The cleaning step (103) is sequentially performed.

  Next, plasma irradiation is performed on the base material whose surface has been roughened and cleaned and from which the shot material has been completely removed (904). This plasma irradiation irradiates the surface of the roughened and cleaned base material to be coated with a plasma particle stream generated by a plasma generator (not shown) to form fine irregularities at the atomic level on the surface. The surface is roughened and simultaneously activated by washing. The fine unevenness at the atomic level is an unevenness that is finer than the unevenness caused by the shot blast described above.

  By this plasma irradiation, the surface of the base material is remarkably improved in adhesion and adhesiveness with a fluororesin that is a different material from the base material.

  Thereafter, similarly to FIG. 1, the fluororesin coating is completed through the steps of fluororesin coating (106) and baking (107).

  In this way, the bonding between the surface of the aluminum alloy base material and the fluorine resin coated thereon becomes very strong, and even when subjected to a strong load such as sliding, the fluorine resin The coating layer is not peeled off or detached.

  Further, as in the case of FIG. 1, since the shot material is poured out with the cleaning liquid and completely separated from the base material, there is no residual shot material, and there is no residual shot material inside during the operation of the gas compressor. No longer flows and damages the sliding part or the like.

  Therefore, the sliding member or gas compressor to which this coating is applied has increased durability, a long life, and improved reliability.

According to the method of FIG. 9, there is no need for a conventional chemical conversion treatment step for generating harmful wastewater, and there is no need for a large and expensive special equipment essential for chemical conversion treatment. The irradiation process is easy to incorporate in the line, and coating can be completed consistently in one coating processing line.

FIG. 10 shows a processing flow of the second embodiment of the fluororesin coating method of the present invention.

  10 includes a laser irradiation process 202 in place of the shot blasting process 102 of FIG. The intensity of the laser beam used in this laser irradiation step 202 is set so that the surface of the base material is slightly melted and roughened, and a pulse laser is scanned over the entire irradiated surface. The irradiation rate of laser irradiation is preferably 44% or more.

  When laser irradiation is used, there is an advantage that it is easier to match the rough surface state to the target state than when shot blasting is used.

  In the plasma irradiation step 904 in FIG. 10, fine irregularities at an atomic level shallower than the depth of the recess formed in the laser irradiation step 202 of the previous step are further formed on the surface of the base material.

  By this plasma irradiation, the surface of the base material is remarkably improved in adhesion and adhesiveness with a fluororesin that is a different material from the base material.

  Hereinafter, the gas compressor of the present invention using the side block 7 will be described with reference to FIGS.

  FIG. 11 is a longitudinal sectional view showing an embodiment of the gas compressor according to the present invention, and FIG. 12 is a sectional view taken along the line XII-XII in FIG. 11, showing the inside of the cylinder chamber. FIG. 13 is a cross-sectional view taken along the line XIII-XIII of FIG. 11 and shows a surface in contact with the cylinder chamber of the front side block. FIG. 14 is a cross-sectional view taken along the line XIV-XIV in FIG. 11 and shows a surface in contact with the cylinder chamber of the side block on the rear side.

  The gas compressor of this embodiment is a well-known vane rotary type, a head portion 2 having an intake chamber 1, a compressor main body portion 3 for introducing and compressing a gas before compression from the intake chamber 1, and the compressor It consists of a rear part 5 having a discharge chamber 4 for containing a gas compressed and discharged by the main body part 3.

  The compressor body 3 includes a cylinder chamber 8 formed in the cylinder block 6 and having end faces surrounded by side blocks 7A and 7B. A rotor 9 is rotatably accommodated in the cylinder chamber 8. The rotor 9 is provided with a plurality of vanes 10 and 10 that can be moved in and out while sliding at the tip to the inner wall surface 6 a of the cylinder block 6 as the rotor 9 rotates. The cylinder chamber 8 is divided into a plurality of compression chambers 11 and 11 by being partitioned by the rotor 9 and the vanes 10 and 10. Each of these compression chambers 11 sequentially sucks gas from the intake chamber 1, compresses the gas by the rotation of the rotor 9, and discharges the gas into the discharge chamber 4.

  The rotor 9 is rotated by being transmitted with rotational power of an engine shaft (not shown) of an automobile via a transmission pulley 12, an electromagnetic clutch 13 and a rotor shaft 14 provided in the head portion 2. . The rotor shaft 14 is fixed through the respective centers of the rotor 9 and the driven portion 13a of the electromagnetic clutch 13, and is rotatably supported by the bearing portions 7j and 7j of both side blocks 7A and 7B.

  When the rotor 9 rotates, the tip of the vane 10 and the inner wall surface 6a of the cylinder block 6 slide. The outer peripheral surface 9a of the rotor 9 and the inner surface 6aa of the short diameter portion of the cylinder block 6 slide. The side surface of the vane groove 9b of the rotor 9 and the side surface of the vane 10 slide. Both end surfaces 9c, 9c of the rotor 9 and cylinder chamber facing surfaces 7x, 7x of both side blocks 7A, 7B slide. Further, both end surfaces of the vane 10 and the cylinder chamber facing surfaces 7x, 7x of the side blocks 7A, 7B slide. Moreover, the cylinder block 6, the side blocks 7A and 7B, the rotor 9 and the vane 10 are made of an aluminum alloy for weight reduction.

  Lubricating oil is supplied to these sliding surfaces. However, the pressure difference between one compression chamber 11 and other compression chambers 11 that repeats suction and compression sequentially is large, and if a gas leak occurs between the compression chambers due to this large pressure difference, a power loss is caused by the amount of the leak, and the compression efficiency Decreases. Therefore, the gaps between the sliding surfaces are made as small as possible, and the lubricating oil film is broken and solid contact tends to occur.

  Therefore, in these sliding surfaces, either one of the sliding surfaces is coated with a fluorine-based resin such as polytetrafluoroethylene, and this coating surface is opposed to the sliding surface of the counterpart aluminum alloy, Conventionally, measures for improving wear resistance and seizure resistance have been taken.

  In order to prevent peeling and detachment of the fluororesin during compressor operation, it is necessary to firmly adhere and bond the aluminum alloy and the fluororesin, and in order to improve the adhesion and adhesion, A process including a ground treatment as shown in FIG. 15 described in the technical section has been adopted.

  In this embodiment, the coating layer on the sliding surface having a large sliding load between the side blocks 7A and 7B, the rotor 9 and the vane 10 is particularly tightly adhered and adhered to the base material as follows. did. That is, polytetrafluoroethylene was coated on the cylinder chamber facing surfaces 7x and 7x of both side blocks 7A and 7B by using the coating method shown in FIG. 1, FIG. 2, FIG. 9 or FIG. As shown in FIGS. 13 and 14, the cylinder chamber facing surface 7 x has recesses 15 and holes for applying vane back pressure, and the surface of these recesses and holes is coated with a coating base such as shot blast. Although the treatment may extend, since there is no risk of remaining shot material, the recesses and holes are completely cleaned in the cleaning process.

  There is no residual shot material in any of the steps using the sodium bicarbonate shot material and the dry ice shot material shown in FIG. 1 or FIG. 9 and the step using the laser irradiation shown in FIG. 2 or FIG. Thus, a polytetrafluoroethylene coating layer that was firmly adhered and adhered to the surface was obtained and was practically usable.

  When the process using plasma irradiation of FIG. 9 or FIG. 10 is entered, the cylinder chamber facing surfaces 7x and 7x of both side blocks 7A and 7B are finely roughened and cleaned at the atomic level by plasma irradiation, and the surfaces are activated. As a result, polytetrafluoroethylene could be adhered and adhered very firmly.

  Examples of the fluororesin that can be used for the fluororesin coating of the present invention include polytetrafluoroethylene, low molecular weight tetrafluoroethylene resin, tetrafluoroethylene-hexafluoropropylene copolymer resin, and vinylidene fluoride resin. And trifluoroethylene chloride resin.

  In the above-described embodiment, the chemical conversion treatment process or the plasma irradiation process is performed before the fluororesin coating process, but the sliding portion having a relatively small sliding load and the surface of the base material in the second cleaning process are clean. In the case where the fluorine-based resin coating can be performed immediately after the formation and before the surface is stained, the chemical conversion treatment step and the plasma irradiation step can be omitted. Since the chemical conversion treatment process has to be performed by a special facility, omission of the chemical conversion treatment process leads to consistent completion of coating in one coating treatment line.

  Furthermore, adhesion and adhesion between the base material and the fluororesin can be achieved by adding a micro-roughening / cleaning process that finely roughens and cleans the surface of the roughened base material by plasma irradiation. It is possible to realize a fluorine resin coating that is further improved in reliability, strong, durable and highly reliable.

Explanatory drawing which shows the processing flow of the fluorine resin coating method (one reference example in describing this invention) . Explanatory drawing which shows the processing flow of the fluororesin coating method (other reference example on describing this invention) . FIGS. 3A and 3B are diagrams for explaining a laser irradiation surface in a laser irradiation step in the processing flow shown in FIG. 2, in which FIG. 2A is an enlarged plan view of the laser irradiation surface, FIG. , (B) Side sectional view. The enlarged plan view of another laser irradiation surface. Explanatory drawing explaining the outline | summary of the test apparatus used for the durability test of the contact surface of a base material and fluororesin. Explanatory drawing which plotted the test result of the fluororesin coating coated aluminum flat member used for the test on the graph which took the laser irradiation dot diameter on the horizontal axis, and took the dot space | interval on the vertical axis | shaft. Explanatory drawing which plotted the test result of the fluorine resin-coated aluminum flat member used for the test, taking the dot area on the horizontal axis and the unit irradiation target area on the vertical axis. Explanatory drawing which shows the relationship between a laser output and a dot diameter. Explanatory drawing which shows the processing flow of 1st Embodiment of the fluorine resin coating method concerning this invention. Explanatory drawing which shows the processing flow of 2nd Embodiment of the fluorine resin coating method concerning this invention. The longitudinal cross-sectional view which shows one Embodiment of the gas compressor which becomes this invention. XII-XII sectional drawing of FIG. XIII-XIII sectional drawing of FIG. XIV-XIV sectional drawing of FIG. Explanatory drawing which shows the processing flow of the conventional fluororesin coating method.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Air intake chamber 2 Head part 3 Compressor main-body part 4 Discharge chamber 5 Rear part 6 Cylinder block 6a Inner wall surface 6aa Short diameter part inner wall surface 7, 7A, 7B Side block 7j Bearing part 7x Cylinder chamber opposing surface 8 Cylinder chamber 9 Rotor 9a Outer periphery Surface 9b Vane groove 9c End surface 10 Vane 11 Compression chamber 12 Transmission pulley 13 Electromagnetic clutch 13a Drive portion 14 Rotor shaft 15 Recess d Dot diameter (diameter of irradiated dot R)
p Dot spacing (pitch)
R Irradiation dot (dent by laser irradiation)
S Irradiation dot area U Unit irradiation target area

Claims (7)

A plasma irradiation step of roughening the surface of the base material of the coating object by plasma irradiation;
A fluororesin coating process for applying a fluororesin coating to the surface of the base material of the coating object roughened by the plasma irradiation;
A firing step of firing the coated surface of the coating object coated with the fluororesin by the fluororesin coating step;
A fluorine resin coating method characterized by comprising:   2. The fluororesin coating method according to claim 1, further comprising a roughening / cleaning treatment step of roughening / cleaning the surface of the coating object before the plasma irradiation step.   3. The fluorine resin coating method according to claim 2, wherein the roughening / cleaning treatment step is a shot blasting step of shot blasting a surface of a coating object with a water-soluble shot material or a vaporizable shot material. .   3. The fluororesin coating method according to claim 2, wherein the roughening treatment / cleaning step is a laser irradiation step of irradiating the surface of the coating object with a laser.   5. A sliding member having a sliding surface coated with a fluorine resin by the fluorine resin coating method according to claim 1.   A gas compressor comprising a sliding member having a sliding surface coated with a fluorine resin by the fluorine resin coating method according to claim 1.   The sliding member having a sliding surface coated with a fluorine-based resin is a side block that surrounds an end surface of a cylinder chamber and slides relative to a rotor and a vane that rotate in the cylinder chamber. Item 7. A gas compressor according to Item 6.

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