JP2007051557A - Vane rotary air pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vane rotary air pump capable of suppressing deterioration in input due to secular change, improving input stability, and lowering noises. <P>SOLUTION: Aluminum alloy having a silicon content of 1.0% or less is used for a cylinder 3 and a cylinder inner peripheral surface is subjected to anodization treatment after applying lapping or grinding, thus an uniform coating is easily formed and carbon is suppressed from being stuck on the cylinder inner peripheral surface. Therefore, even when relative humidity of air sucked into the pump is increased, input rise is suppressed, deterioration in input due to secular change is suppressed, input stability is improved, and noises can be lowered. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a configuration of a vane rotary type air pump used in an air supply device of a mobile information terminal device using a fuel cell.

  Conventionally, this type of vane rotary type pump uses an Al—Si based aluminum alloy as a material of a cylinder (for example, see Patent Document 1). 5 and 6 show a conventional vane rotary pump described in Patent Document 1. In FIG. A cylinder 3 having a cylindrical inner wall closed at both ends by a front plate 1 and an end plate 2 is provided. Inside the cylinder 3, a rotor 4 is arranged in which a part of the outer periphery forms a small gap with the inner wall of the cylinder 3.

A plurality of slits 5 are formed on the outer peripheral surface of the rotor 4, and one end of a vane 6 is slidably inserted into each slit 5. The vane 6 forms a pump space 7 together with the cylinder 3, the rotor 4, the front plate 1, and the end plate 2. The material of the vane 6 is carbon.
Japanese Patent Laid-Open No. 62-276291

  However, in the conventional configuration, when an anodizing treatment is applied to an Al-Si based aluminum alloy cylinder, an anodized film is hardly formed on the portion where silicon is deposited on the cylinder surface, and a uniform film is formed. It may not be formed. When carbon scraped by the sliding of the vane adheres to the uneven film portion and the relative humidity of the air sucked into the pump becomes high, the viscosity of the adhering carbon increases and the input increases. It had the problem that.

  The present invention solves the above-described conventional problems, and aims to provide a vane rotary type air pump that suppresses carbon adhesion to the inner peripheral surface of a cylinder, suppresses an increase in input, and improves input stability. It is to do.

  In order to solve the above-mentioned conventional problems, the vane rotary type air pump of the present invention uses an aluminum alloy having a silicon content of 1.0% or less for a cylinder and anodizes the surface thereof. .

  As a result, sufficient strength can be ensured, the silicon content is small, and the deposition of silicon on the cylinder surface is reduced, so that an anodized film can be formed uniformly. Therefore, carbon scraped by the sliding of the vane is less likely to adhere to the inner circumferential surface of the cylinder, and even when the relative humidity of the air sucked into the pump becomes high, an increase in input can be suppressed.

  The vane rotary type air pump of the present invention suppresses the adhesion of carbon to the cylinder inner peripheral surface due to the sliding of the vane, and suppresses the increase in input even when the relative humidity of the air sucked into the pump changes. , Input stability can be improved.

In the first invention, an aluminum alloy having a silicon content of 1.0% or less is used on the inner peripheral surface of the cylinder, and an anodizing treatment is performed on the surface, whereby a uniform film can be easily formed. Since carbon adhesion to the peripheral surface can be suppressed, an increase in input can be suppressed and input stability can be improved even when the relative humidity of the air sucked into the pump becomes high.

  In the second invention, in particular, by using an Al—Mg-based aluminum alloy as the material of the cylinder of the first invention, sufficient strength can be ensured and the silicon content is further reduced, so that the uniformity is more uniform. An anodized film can be easily formed, and carbon adhesion to the inner peripheral surface of the cylinder can be further suppressed. Therefore, even when the relative humidity of the air sucked into the pump becomes high, an increase in input can be suppressed and input stability can be effectively improved.

  In the third aspect of the invention, the surface roughness is improved by applying lapping or grinding to the cylinder inner surface of the second aspect of the invention before the anodic oxidation treatment, the slidability with the vane tip is improved, and the initial input is improved. Reduction is possible.

  In the fourth invention, since the self-lubricating performance of carbon can be secured by setting the average surface roughness of lapping or grinding of the third invention in the range of 0.15 μm to 0.25 μm, the initial input is increased. It is possible to reduce initial noise while suppressing noise.

  The fifth aspect of the invention can improve the deterioration of the surface roughness caused by the anodizing process by performing lapping or grinding especially after the anodizing process of the fourth invention, and further reduce the initial noise. Can do.

  In the sixth aspect of the invention, in particular, the self-lubricating performance of carbon can be secured by setting the average surface roughness of the lapping or grinding of the fifth aspect in the range of 0.15 μm to 0.25 μm. The initial noise can be reduced while suppressing the rise.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
1 and 2 are sectional views of a vane rotary type air pump according to Embodiment 1 of the present invention.

  1 and 2, the vane rotary type air pump includes a pump mechanism unit 8 and a DC motor 9.

  A cylindrical rotor 4 is disposed in a cylinder 3 having a cylindrical inner wall and anodized on the inner peripheral surface with the central axis of the cylindrical inner wall of the cylinder 3 and the central axis of the rotor 4 being eccentric. The rotor 4 is provided with a plurality of slits 5 in the direction of the central axis thereof, and a plate-like vane 6 made of a self-lubricating carbon material is fitted in the slits 5 in a slidable state, and the front plate 1 and the end plate 2 are arranged on the end face of the cylinder 3 so as to sandwich the rotor 4 and the vane 6 to form a plurality of pump spaces 7, and the central axis of the rotor 4 is arranged on the opposite mechanism side of the end plate 2. A mechanical shaft 10 that also serves as a motor shaft of the DC motor 9 is coupled and can be rotated by a ball bearing 11 press-fitted into the front plate 1 and a ball bearing 12 press-fitted into the end plate 2. Constitute a pumping mechanism portion 8 by supporting.

The inner peripheral surface of the cylinder 3 is lapped in the circumferential direction and the same direction as the sliding direction of the tip of the vane 6 after lathe processing. If the average surface roughness is improved, the initial noise can be reduced. However, if the average surface roughness is too high, the self-lubricating performance of the carbon is lowered, and the initial input is caused by a sliding failure between the inner peripheral surface of the cylinder 3 and the tip of the vane 6 Therefore, the average surface roughness is adjusted to 0.20 [μm].

  Thereafter, anodization is performed. The anodizing treatment is necessary for preventing rust and improving the wear resistance of the inner peripheral surface of the cylinder 3. The film thickness of the anodized film on the inner peripheral surface is 5 [μm].

  Further, when anodizing is performed, the surface roughness is slightly deteriorated and the noise value in the frequency band from 8 kHz to 16 kHz is increased. Therefore, lapping is performed again in the same direction as the sliding direction of the tip of the vane 6 again after the processing. The average surface roughness is adjusted to 0.20 [μm]. If the average surface roughness is also improved, the initial noise can be reduced. However, if the average surface roughness is too high, the self-lubricating performance of the carbon is lowered, and the inner peripheral surface of the cylinder 3 and the tip of the vane 6 are reduced. This is because the initial input deteriorates due to the sliding failure. Although lapping is performed in the present embodiment, the surface may be finished by superfinishing.

  In the DC motor 9, a stator 14 is disposed on the outer periphery of a motor rotor 13, and a mechanical shaft 10 that also serves as a motor shaft is supported by a bearing 15 and a bearing 16.

  According to this component, the motor rotor 13 obtains rotational torque and rotates by the magnetic action between the motor rotor 13 and the stator 14. The mechanical shaft 10 serving as a motor shaft integrally formed with the motor rotor 13 is rotatably supported by the bearings 11 and 12, so that the rotational force can be transmitted to the pump mechanism unit 8.

  The rotational force output by the DC motor 9 is transmitted to the rotor 4 coupled to the mechanical shaft 10 that also serves as the motor shaft. Along with the rotation of the rotor 4 that has obtained the rotational force, the vane 6 jumps out along the slit 5 provided in the central axis direction of the rotor 4 by centrifugal force, thereby forming the pump space 7. At the same time, the air sucked from the suction port 17 flows directly into the pump space 7, the route flows into the pump space 7 from the stepped portion 19 provided in the end plate 2 through the through hole 18 provided in the cylinder 3, It flows into the pump space 7 from three places of the path flowing into the pump space 7 from the communication passage 20 provided in the center of the cylinder through the through hole 18.

  The inflowing air is compressed in the pump space 7 as the rotor 4 rotates, and is discharged from the discharge port 22 through the discharge port 21.

  FIG. 3 is a graph showing a comparison of inputs when a cylinder 3 made of an Al—Si based and Al—Mg based aluminum alloy is used.

  The horizontal axis shows elapsed time, and the vertical axis shows input. The initial input shows almost the same value for both Al-Si and Al-Mg, but the input after 500 hours in continuous operation is 40% of the initial value ratio of the Al-Si input. On the other hand, the Al-Mg system is 15%.

  Since it is difficult to form an anodized film on the portion where silicon is deposited, a uniform film surface becomes difficult to obtain as the silicon content increases. The Al-Si system has a silicon content of about 10%, and the Al-Mg system is 0.4% or less. Therefore, the Al-Si-based cylinder 3 has more non-uniform film portions, that is, dents, where carbon adheres more than the Al-Mg-based, and the relative humidity of the sucked air becomes higher. In this case, the viscosity of the attached carbon also increases, the sliding with the tip of the vane 6 deteriorates, and the input increases.

  Therefore, if the cylinder 3 is made of an Al—Mg-based aluminum alloy, the amount of carbon adhering due to changes over time can be reduced even when anodizing is performed, and an increase in input can be suppressed.

(Embodiment 2)
FIG. 4 is a graph showing the relationship between the presence / absence of lapping and an input before anodizing treatment of the vane rotary type air pump according to the second embodiment of the present invention.

  The cylinder 3 without wrapping before anodizing is adjusted to an average surface roughness of 0.20 [μm] by lathe processing, and then anodized. The anodizing treatment is necessary for rust prevention and wear resistance improvement of the inner peripheral surface of the cylinder 3, and the film thickness of the anodized film is 5 [μm]. Further, when the anodizing treatment is performed, the surface roughness is slightly deteriorated and the noise value in the frequency band from 8 kHz to 16 kHz is increased. Therefore, lapping is performed in the circumferential direction and the sliding direction of the tip of the vane 6 after the treatment, The average surface roughness is adjusted to 0.20 [μm]. If the average surface roughness is improved, the initial noise can be reduced. However, if the average surface roughness is too high, the self-lubricating performance of the carbon is lowered, and the inner peripheral surface of the cylinder 3 and the tip of the vane 6 are reduced. This is because the initial input deteriorates due to the sliding failure. Although lapping is performed in the present embodiment, the surface may be finished by superfinishing.

  The cylinder 3 with lapping before anodizing is processed by lathe processing and then lapped in the circumferential direction and in the same direction as the sliding direction of the tip of the vane 6 to obtain an average surface roughness. Is adjusted to 0.20 [μm]. Thereafter, anodization is performed. The anodizing treatment is necessary for rust prevention and wear resistance improvement of the inner peripheral surface of the cylinder 3, and the film thickness of the anodized film on the inner peripheral surface is 5 [μm]. Further, when the anodizing treatment is performed, the surface roughness is slightly deteriorated and the noise value in the frequency band from 8 kHz to 16 kHz is increased. The average surface roughness is adjusted to 0.20 [μm]. Although lapping is performed in the present embodiment, the surface may be finished by superfinishing.

  In the cylinder 3 without wrapping before the anodizing treatment, the initial input is deteriorated by 34% as compared with the presence.

  The average surface roughness before treatment is 0.20 [μm] regardless of the presence or absence of lapping, but the Al—Mg based aluminum alloy has higher toughness than the Al—Si based aluminum alloy, Since the material tends to cling to the cutting tool at the time of cutting, peeling occurs and there are more places where a smooth cut surface is not obtained than in the Al-Si system. When the tip of the vane 6 passes through this non-smooth portion, it becomes a resistance, and the input deteriorates from the beginning of operation. However, by lapping the inner peripheral surface of the cylinder 3 before the anodizing treatment, it is possible to finish this portion smoothly, the tip of the vane 6 can slide without resistance, and the input at the initial stage of operation is reduced. be able to. Further, when lapping is performed after the anodizing treatment, the surface hardness is increased by the anodizing treatment, so that it is difficult to smooth the portion roughened by the peeling.

  As described above, the vane rotary type air pump according to the present invention has high input stability and low noise, and therefore can be applied to uses such as home health equipment and medical treatment equipment.

Sectional drawing of the axial direction of the vane rotary type | mold air pump in Embodiment 1 of this invention Sectional drawing of radial direction of vane rotary type air pump in Embodiment 1 of this invention Comparison diagram of air pump input when using Al-Si and Al-Mg cylinders in Embodiment 1 of the present invention Comparison diagram of presence / absence of wrapping before anodizing treatment and input at the initial stage of operation in Embodiment 2 of the present invention Radial sectional view of a conventional vane rotary air pump A sectional view in the axial direction of a conventional vane rotary type air pump

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Front plate 2 End plate 3 Cylinder 4 Rotor 5 Slit 6 Vane 7 Pump space 8 Pump mechanism part 9 DC motor 10 Mechanical shaft 11, 12 Ball bearing 13 Motor rotor 14 Stator 15, 16 Bearing 17 Suction port 18 Through-hole 19 Paragraph part 20 Communication path 21 Discharge port 22 Discharge port

Claims (6)

A cylinder-shaped rotor is disposed in a cylinder having a cylindrical inner wall in a state where the central axis of the cylindrical inner wall of the cylinder and the central axis of the rotor are eccentric, and the rotor has a plurality of central axis directions. Slits are provided, and the plate-like vanes made of a self-lubricating carbon material are fitted in these slits in a slidable state, and a front plate and an end plate having suction ports are connected to the rotor and the vanes. A pump space is formed on the end face of the cylinder so as to sandwich it, a mechanical shaft is provided on the central axis of the rotor to constitute a pump mechanism, and a motor is arranged on the non-mechanical side of the end plate. When the motor drives the mechanical shaft, the rotor rotates, and the vane tip reciprocates in the slit while the vane tip moves. The oil-less air pump that slides along the inner wall of the cylinder causes the pump space to expand and contract, and repeatedly sucks, compresses and discharges air. The cylinder has a silicon content of 1.0%. A vane rotary type air pump using the following aluminum alloy and anodizing the surface. The vane rotary type air pump according to claim 1, wherein the cylinder uses an Al-Mg based aluminum alloy. The vane rotary type air pump according to claim 1 or 2, wherein the inner peripheral surface of the cylinder is lapped or ground before the anodizing treatment of the cylinder. The vane rotary type air pump according to claim 3, wherein an average surface roughness of lapping or grinding applied to the inner peripheral surface of the cylinder before the anodizing treatment of the cylinder is in a range of 0.15 µm to 0.25 µm. The vane rotary type air pump according to claim 4, wherein the cylinder inner peripheral surface is lapped or ground after the anodizing treatment of the cylinder. The vane rotary type air pump according to claim 5, wherein an average surface roughness of lapping or grinding applied to the inner peripheral surface of the cylinder after the anodizing treatment of the cylinder is in a range of 0.15 µm to 0.25 µm.

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