JP2008051146A - Rotary valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotary valve which can prevent the wear of both a fixed-side member and a rotary-side member even if a foreign matter intrudes into a sliding surface (sealing surface) between the fixed-side member and the rotary-side member, and can avoid both the members from becoming wear-out components. <P>SOLUTION: In the rotary valve which comprises the fixed-side member 33 and the rotary-side member 36, and in which an arc-shaped groove 40 formed at the fixed-side member 33 and a communication hole 52 formed at the rotary-side member 36 are made to intermittently communicate with each other by the relative rotation of the fixed-side member 33 and the rotary-side member 36 while they slidably contact with each other, the rotary-side member 36 is supported by a bearing, the fixed-side member 33 is formed of alumina ceramic, and the rotary-side member 36 is formed of carbon ceramic. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a rotary valve, and more particularly, to a rotary valve that can be suitably used for a container transport device that transports a container adsorbed by a vacuum suction unit at a high speed.

  Generally, a rotary valve includes a stationary member and a rotating member that rotate relative to each other while being in sliding contact with each other. For example, negative pressure from a vacuum source connected to the stationary member is supplied to the rotating member. It is used when doing so. A configuration example of this rotary valve will be described. A communication hole is formed in the fixed side member, and one end of the communication hole is connected to an arc-shaped groove formed on the sliding surface of the fixed side member. A plurality of communication holes are formed in the rotation side member, and one ends of these communication holes are opened at the sliding contact surface of the rotation side member so as to be able to face the arc-shaped groove described above.

  Under such a configuration, when the rotation side member and the fixed side member rotate relative to each other while sliding, the rotary valve is opened only while the communication hole of the rotation side member faces the arc-shaped groove of the fixed side member, Fluid can be exchanged between a vacuum source or a compressed air source connected to the stationary member and an operation unit such as an adsorption unit connected to the rotating member. On the other hand, when the communication hole of the rotation side member deviates from the arc-shaped groove of the fixed side member, the rotary valve is closed and the exchange of fluid between the rotation side member and the fixed side member is blocked.

  The rotary valve configured as described above is widely used in a container transport device that transports a container at a high speed and inspects the container. A general container transport device includes a star wheel having an adsorption part, and conveys the container by rotating the star wheel at high speed while adsorbing the container to the adsorption part by a negative pressure from a vacuum source such as a vacuum pump. Configured. Normally, since the vacuum source such as a vacuum pump is fixedly installed, the rotary valve described above is used to supply the negative pressure from the vacuum source to the rotating star wheel side from the fixed side where the vacuum source is arranged. It is used.

  In such a rotary valve, since the stationary member and the rotating member are in sliding contact with each other while being attracted to each other by negative pressure, wear of the sliding contact surface easily proceeds. For this reason, conventionally, a combination of alumina ceramics has been used as a material for forming the stationary member and the rotating member. However, in the case of a combination of the above-mentioned alumina ceramics, there is a problem that the sliding resistance is large and the fixed side member and the rotating side member are worn simultaneously.

In order to solve the above-mentioned wear problem, the present applicant uses carbon ceramics as a material for either or both of the fixed side member and the rotary side member in Patent Document 1 (Japanese Patent Laid-Open No. 2003-97746). The rotary valve which supported the member with the thrust bearing is proposed. Although the rotary valve disclosed in Patent Document 1 has a description of using carbon ceramics for either the fixed side member or the rotary side member, as a specific configuration, either the fixed side member or the rotary side member is described. Only examples using carbon ceramics are disclosed.
JP 2003-97746 A

  In the rotary valve disclosed in Patent Literature 1, immediately after assembly, the stationary member and the rotating member are brought into direct sliding contact, and the rotating member is supported only by the sliding contact surface. When the rotation side member is rotated in this state, the fixed side member and the rotation side member slide and the sliding contact surface gradually wears. By this wear, first, the surface accuracy of the sliding contact surfaces of the rotating side member and the stationary side member formed of carbon ceramics can be obtained. As wear of the sliding contact surfaces of the stationary member and rotating member further progresses, the rotating member is supported by the thrust bearing, and the sliding contact surface is merely familiar and in contact with it. Wear does not progress.

  However, in the above-described rotary valve, when a foreign member such as glass or metal fine powder enters the sliding contact surface (seal surface) after the rotation side member is supported by the thrust bearing, the fixed side member There is a problem that both the rotating side member and the rotating side member are worn. When both the fixed side member and the rotary side member are worn as described above, there is a problem that vacuum leakage occurs, and there is a problem that both these members become consumable parts.

  The present invention has been made in view of the above circumstances, and even when a foreign object enters the sliding contact surface (seal surface) of the stationary member and the rotating member, both the stationary member and the rotating member are worn. It is an object of the present invention to provide a rotary valve that can prevent both members from becoming consumable parts and prevent vacuum leakage due to wear.

  Further, the present invention has occurred in the sliding contact surfaces of the fixed side member and the rotation side member by supplying a liquid such as water having a function as a lubricant to the sliding contact surfaces of the fixed side member and the rotation side member. An object of the present invention is to provide a rotary valve capable of reducing wear and preventing the generation of abnormal noise.

According to the first aspect of the present invention, the fixed-side member and the rotating-side member are provided, and the fixed-side member and the rotating-side member are formed on the fixed-side member by rotating relative to each other while being in sliding contact with each other. In the rotary valve configured to intermittently communicate the formed arc-shaped groove and the communication hole formed in the rotation side member, the rotation side member is supported by a bearing, and the fixed side member is made of alumina ceramics. The rotation side member is made of carbon ceramics.
According to a preferred aspect of the present invention, the bearing is a thrust bearing.

According to the second aspect of the present invention, the fixed-side member and the rotation-side member are provided, and the fixed-side member and the rotation-side member are formed in the fixed-side member by rotating relative to each other while being in sliding contact with each other. In the rotary valve configured to intermittently communicate the formed arc-shaped groove and the communication hole formed in the rotary side member, the fixed side member is slidably contacted with the fixed side member. A liquid supply hole for supplying liquid to the surface is formed.
According to a preferred aspect of the present invention, the liquid supply hole is connected to a liquid supply tank disposed above the liquid supply hole so that the liquid can be supplied to the sliding contact surface by a water head difference.

  According to the present invention, since the fixed side member is formed of alumina ceramics and the rotation side member is formed of carbon ceramics, hard alumina ceramics do not wear but only soft carbon ceramics wear. Therefore, even when a foreign object enters the sliding contact surface between the stationary member and the rotating member, only the rotating member is worn or damaged, and only the rotating member becomes a consumable part, which is very advantageous in terms of maintenance cost.

  In addition, according to the present invention, wear that has occurred on the sliding contact surfaces of the fixed member and the rotating member by supplying a liquid having a function as a lubricant to the sliding surfaces of the fixed member and the rotating member. Can be significantly reduced, and abnormal noise can be prevented.

Hereinafter, an embodiment of a rotary valve according to the present invention will be described with reference to the drawings.
FIG. 1 is a plan view of a container inspection apparatus provided with a rotary valve according to this embodiment.
As shown in FIG. 1, a container inspection apparatus including a rotary valve according to this embodiment includes a carry-in conveyor 2 for carrying a container 1 to be inspected into the container inspection apparatus, and a container inspection by receiving the container 1 from the carry-in conveyor 2. A loading star wheel 3 to be loaded into the unit 4, a container inspection unit 4 for inspecting the container 1 received from the loading star wheel 3, a unloading star wheel 5 for unloading the container 1 after the inspection, and the container 1 outside the apparatus A first carry-out conveyor 6a and a second carry-out conveyor 6b.

  The carry-in conveyor 2 is arranged adjacent to the carry-in star wheel 3, and the first carry-out conveyor 6 a and the second carry-out conveyor 6 b are arranged adjacent to the carry-out star wheel 5. An infeed screw 7 is provided adjacent to the carry-in star wheel 3 and parallel to the carry-in conveyor 2. The container 1 to be inspected is carried into the container inspection apparatus from the direction of arrow A by the carry-in conveyor 2, and a fixed interval is formed by the infeed screw 7 and is sequentially delivered to the carry-in star wheel 3. Thereafter, the container 1 is conveyed to the container inspection unit 4 by the carry-in star wheel 3 while being guided by the guide rails 8, and the container 1 is sequentially inspected by the imaging device 9 having a CCD camera. Then, the container 1 that has been inspected is transferred to the carry-out star wheel 5, the container 1 that has been determined to be defective by the container inspection unit 4 is conveyed by the first carry-out conveyor 6 a, and the container 1 that has been determined to be good is the first one. 2 It is conveyed to the next process by the carry-out conveyor 6b.

Next, the container inspection part provided with the rotary valve according to the present embodiment will be described.
FIG. 2 is a cross-sectional view of a container inspection unit including a rotary valve according to the present embodiment. FIG. 3A is an enlarged cross-sectional view of a portion B in FIG. 2, and FIG. 3B is an enlarged cross-sectional view immediately after the assembly of the rotary valve according to the present embodiment.

  As shown in FIG. 2, the container inspection unit 4 includes a main rotor 21 that rotates while holding the container 1 to be inspected. The main rotor 21 is fixed to a main shaft 23, and the main shaft 23 is rotatably supported by a bearing 22. A motor (not shown) is connected to one end of the main shaft 23, and the main shaft 23 is driven to rotate by this motor so that the main rotor 21 rotates at a high speed.

  A plurality of support bases 24 for placing the containers 1 are disposed on the outer periphery of the main rotor 21, and each support base 24 is provided with an adsorption pad 25 for adsorbing and holding the containers 1. ing. A pulley 26 is provided at the lower part of each support base 24, and a spin belt (not shown) that runs while contacting the V-shaped groove of the pulley 26 is installed in the vicinity of the outer periphery of the main rotor 21. The support base 24 and the pulley 26 are connected to each other by a shaft 27 and are configured to rotate integrally. When the spin belt comes into contact with the V-shaped groove of the pulley 26, the support base 24 and the support base 24 are in contact with each other. The held container 1 is rotated. The shaft 27 is fixed to the main rotor 21 and is rotatably supported by a bearing device 28 incorporating a bearing.

  In this embodiment, a vacuum pump (not shown) is used as a vacuum source for adsorbing the container 1. Since this vacuum pump is fixedly installed, the rotary valve 31 according to this embodiment is used to supply negative pressure from the fixed side (vacuum pump side) to the rotating side (main rotor side). As shown in FIGS. 3 to 5, the rotary valve 31 includes a disk-shaped fixed side member 33 fixed to the fixed base 32 and a disk-shaped rotation side member 36 fixed to the cylindrical body 35. I have. The cylindrical body 35 and the main shaft 23 are connected via a key 38 provided on the main shaft 23, and the cylindrical body 35, the rotation side member 36, and the main shaft 23 are configured to rotate integrally.

  The fixed side member 33 and the rotation side member 36 have a sliding contact surface (seal surface) 39 that rotates while being in sliding contact with each other. 4 (a) and 4 (b) are diagrams showing the fixed-side member, FIG. 4 (a) is a plan view showing the sliding surface side of the fixed-side member, and FIG. 4 (b) is FIG. It is CC sectional view taken on the line of (a). As shown in FIGS. 4 (a) and 4 (b), the sliding contact surface 39 of the fixed member 33 has a vacuum arcuate groove 40 extending at an angle of approximately 180 degrees, and approximately 30 degrees. An arcuate groove 41 for compressed air extending at an angle and a water supply hole 42 for water supply are formed. A first communication hole 43 communicating with the arcuate groove 40 for vacuum is formed in the fixed side member 33, and the first communication hole 43 is connected to a vacuum source 45 including a vacuum pump through a pipe 44. . The fixed member 33 is formed with a second communication hole 46 communicating with the arcuate groove 41 for compressed air, and the second communication hole 46 is connected to a compressed air source 48 such as a compressor via a pipe 47. . Further, the water supply hole 42 of the fixed side member 33 is connected to the small capacity tank 55 through the pipe 50.

  FIG. 5 is a view showing the rotation side member, FIG. 5 (a) is a plan view showing the sliding surface side of the rotation side member 36, and FIG. 5 (b) is a DD line in FIG. 5 (a). It is sectional drawing. As shown in FIG. 5A and FIG. 5B, the sliding contact surface 39 of the rotation side member 36 has a plurality of openings that open at positions facing the arc-shaped groove 40, the arc-shaped groove 41, or the water supply hole 42. The communication hole 52 is formed on the same circumference. And each communicating hole 52 of the rotation side member 36 is connected to each adsorption pad 25 via the piping 53 (refer FIG. 2).

The fixed-side member 33 is made of alumina ceramic. This alumina ceramic is a sintered body mainly composed of alumina (Al ₂ O ₃ ), making use of high-density and high-hardness alumina, heat resistance and insulation. Resistance characteristics are better than other ceramics. On the other hand, the rotation side member 36 is formed of carbon ceramics, and the carbon ceramics are produced by compounding semi-fine coke as a raw material base with ceramics such as extremely fine SiC and B ₄ C. It has various excellent properties as follows.

For example, in carbon ceramics, ceramics such as fine SiC and B ₄ C are grown and uniformly dispersed in a graphite matrix, and these ceramics react with oxygen in the atmosphere to form on the surface of the carbon ceramics. A glass layer (SiO ₂ · B ₂ O ₃ ) of about 70 μm is formed. And with this glass layer, good lubricity can be obtained on the surface of the carbon ceramics. The reaction formula for forming the glass layer is represented by the following formula.
SiC + B ₄ C + O ₂ → SiO ₂ .B ₂ O ₃ + CO ₂
Moreover, since carbon ceramics is excellent in machinability, it can be easily processed into a desired shape at low cost. In addition, it has excellent properties such as high strength, thermal shock resistance, and low water absorption.

  As shown in FIG. 3A, the rotary valve 31 according to this embodiment includes a thrust bearing 51 for supporting the rotation side member 36. The thrust bearing 51 is installed on the fixed base 32 to which the fixed side member 33 is fixed, and supports the cylindrical body 35 to which the rotation side member 36 is fixed. That is, the rotation side member 36 is supported by the above-described sliding contact surface 39 and also supported by the thrust bearing 51 via the cylindrical body 35.

Next, a water supply system for supplying water to the sliding contact surface (seal surface) 39 of the fixed side member 33 and the rotation side member 36 will be described with reference to FIG.
As shown in FIG. 2, the water supply hole 42 of the fixed side member 33 is connected to a small capacity tank 55 through a pipe 50. The small capacity tank 55 is connected to the large capacity tank 57 by a pipe 56. The piping 50 is provided with an opening / closing valve V1, a needle valve V2, and a first electromagnetic valve EV1. The pipe 56 is provided with an opening / closing valve V4 and a second electromagnetic valve EV2. The small-capacity tank 55 is provided with a first water level sensor S1 and a second water level sensor S2. The small capacity tank 55 is provided with an air vent pipe 58.

According to the water supply system configured as described above, during operation of the apparatus, the first electromagnetic valve EV1 is turned on, and water is supplied from the small capacity tank 55 to the water supply hole 42 of the fixed side member 33 via the pipe 50. As a result, water is supplied to the sliding contact surface (seal surface) 39 of the stationary member 33 and the rotating member 36.
The replenishment of water from the large capacity tank 57 to the small capacity tank 55 is performed as follows. That is, when the first water level sensor S1 and the second water level sensor S2 are in the OFF state, the water level of the small-capacity tank 55 is below the second water level sensor S2. Accordingly, when the first water level sensor S1 and the second water level sensor S2 are OFF, the second electromagnetic valve EV2 is turned ON, and water is supplied from the large capacity tank 57 to the small capacity tank 55. When the second water level sensor S2 and the first water level sensor S1 are turned on, the water level in the small capacity tank 55 has been recovered to the position of the second water level sensor S2, and the second electromagnetic valve EV2 is turned off, resulting in a large capacity. Water supply from the tank 57 to the small capacity tank 55 is stopped. Note that an alarm is issued if the first water level sensor S1 does not turn on even after a predetermined time has passed since the second electromagnetic valve EV2 is turned on. In addition, if the second water level sensor S2 does not turn OFF even after a certain period of time has elapsed from the start of operation, an alarm of poor water supply is issued.

  According to the rotary valve 31 configured as shown in FIGS. 2 to 5, when the rotation side member 36 rotates while slidingly contacting the fixed side member 33, the communication hole 52 formed in the rotation side member 36 becomes the fixed side member. While in a position facing the arc-shaped groove 40 formed in 33, the negative pressure from the vacuum source 45 is supplied to the suction pad 25 via the arc-shaped groove 40 and the communication hole 52 of the rotation side member 36, and the container 1 Is sucked and held by the suction pad 25. Further, when the communication hole 52 of the rotation side member 36 is displaced from the arc-shaped groove 40, the negative pressure from the vacuum source 45 is cut off, and the suction holding of the container 1 by the suction pad 25 is released. Immediately after that, the communication hole 52 of the rotating side member 36 faces the arcuate groove 41 for compressed air formed in the stationary member 33, and the compressed air from the compressed air source 48 such as a compressor is supplied to the arcuate groove 41 and the rotating side. The suction air is supplied to the suction pad 25 through the communication hole 52 of the member 36, the compressed air is ejected from the suction pad 25, and the container 1 is completely detached from the suction pad 25.

  Here, in the rotary valve, it is necessary to keep the stationary member 33 and the rotating member 36 in sliding contact with each other to ensure airtightness. For this reason, even when the rotation side member 36 is supported by the thrust bearing 51, it is necessary to prevent a gap from being generated between the fixed side member 33 and the rotation side member 36. Therefore, in the present embodiment, as shown in FIG. 3B, as a configuration immediately after assembly, a clearance d of about 30 μm is provided between the thrust bearing 51 and the cylindrical body 35, and rotation is performed only on the sliding contact surface 39. The side member 36 is supported. When the rotation side member 36 rotates in this state, the fixed side member 33 and the rotation side member 36 slide, and the sliding contact surface 39 of the rotation side member 36 made of carbon ceramics gradually wears. By this wear, first, the surface accuracy of the sliding contact surface 39 of the rotation side member 36 formed of carbon ceramics can be obtained.

  As the wear of the sliding contact surface 39 further proceeds, the cylindrical body 35 eventually comes into contact with the thrust bearing 51, and the load applied to the thrust bearing 51 gradually increases. Finally, the rotation side member 36 and the cylindrical body 35 are mostly supported by the thrust bearing 51, and the sliding contact surface 39 is merely familiar and in contact with each other. Wear does not progress. As the thrust bearing to be used, a needle roller bearing is particularly suitable.

  According to the rotary valve of the present embodiment, water can be supplied from the small-capacity tank 55 to the slidable contact surface 39 of the stationary member 33 and the rotating member 36 at all times while the rotary valve is operating. Water supply to the slidable contact surface 39 is performed by a water head difference between the small-capacity tank 55 and the slidable contact surface 39, and the amount of water supplied is as extremely small as 20 to 30 ml / h. This water supply lubricates the sliding contact surface 39, so that the wear of the sliding contact surface 39 can be remarkably reduced and the occurrence of abnormal noise can be prevented. In addition, since each communication hole 52 of the rotation side member 36 is set to rotate in a direction in which the arc-shaped groove 40, the arc-shaped groove 41, and the water supply hole 42 communicate with each other, When the communication hole 52 faces the water supply hole 42, the suction pad 25 and the pipe 53 are already at atmospheric pressure. Therefore, water is not sucked into the suction pad 25 or the pipe 53. Further, since the amount of water supplied to the sliding contact surface 39 is as small as 20 to 30 ml / h, water does not overflow from the sliding contact surface 39, and water is transmitted to the vacuum source 45 through the sliding contact surface 39. There is no fear of being inhaled.

Next, the operation of the container inspection unit configured as described above will be described.
When the main rotor 21 rotates and approaches the position where the container 1 is delivered from the carry-in star wheel 3, the communication hole 52 of the rotation side member 36 that rotates integrally with the main rotor 21 is formed in the arc-shaped groove 40 of the fixed side member 33. Get closer to. The communication hole 52 of the rotation side member 36 and the arcuate groove 40 of the fixed side member 33 are opposed to each other immediately before the delivery position of the container 1, whereby the communication hole 52 of the rotation side member 36 and the first communication hole are arranged. 43 communicates. That is, the negative pressure from the vacuum source 45 is supplied to the suction pad 25 so that the suction pad 25 can be sucked. In this state, the container 1 is transferred from the carry-in star wheel 3 to the main rotor 21, and at the same time, the bottom surface of the container 1 is sucked and held by the suction pad 25.

  The container 1 held by the suction pad 25 is transported by the main rotor 21, and the container 1 is inspected by the imaging device 9 during transport. When the inspection-finished container 1 reaches the delivery position of 5 to the carry-out star wheel, the communication hole 52 of the rotation side member 36 is displaced from the arc-shaped groove 40, and the suction state of the suction pad 25 is released. Immediately thereafter, the communication hole 52 of the rotation side member 36 faces the arcuate groove 41 of the fixed side member 33, and as a result, compressed air is supplied to the adsorption pad 25, and the container 1 is completely detached from the adsorption pad 25. . Then, the container 1 that has left the main rotor 21 is delivered to the carry-out star wheel 5.

  In the above-described embodiment, an example in which water as a lubricant is supplied to the sliding contact surface 39 of the fixed side member 33 and the rotation side member 36 from the water supply hole 42 formed in the fixed side member 33 has been described. As long as it is a liquid which has an effect | action, it may be another liquid not only water. The water supply hole 42 functions as a liquid supply hole for supplying a liquid lubricant to the sliding contact surface 39. The small-capacity tank 55 functions as a liquid supply tank for supplying liquid to the sliding contact surface 39 with a water head difference.

It is a top view of the container inspection apparatus provided with the rotary valve concerning this embodiment. It is sectional drawing of the container test | inspection part provided with the rotary valve which concerns on this embodiment. FIG. 3A is an enlarged cross-sectional view of a portion B in FIG. 2, and FIG. 3B is an enlarged cross-sectional view immediately after the assembly of the rotary valve according to the present embodiment. FIG. 4A is a plan view showing the slidable contact surface side of the fixed member, and FIG. 4B is a cross-sectional view taken along the line CC of FIG. 4A. FIG. 5A is a plan view showing the sliding surface side of the rotation side member 36, and FIG. 5B is a sectional view taken along the line DD of FIG. 5A.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Container 2 Carry-in conveyor 3 Carry-in star wheel 4 Container inspection part 5 Carry-out star wheel 6a, 6b Carry-out conveyor 7 Infeed screw 8 Guide rail 9 Imaging device 21 Main rotor 22, 23 Bearing 24 Support stand 25 Suction pad 26 Pulley 27 Shaft 28 Bearing device 31 Rotary valve 32 Fixed base 33 Fixed side member 35 Cylindrical body 36 Rotating side member 38 Key 39 Sliding contact surface 40, 41 Arc-shaped groove 42 Water supply holes 43, 46, 52 Communication holes 44, 50, 53, 56 Piping 45 Vacuum source 47 Piping 48 Pressure air source 51 Thrust bearing 55 Small capacity tank 57 Large capacity tank V1 Open / close valve V2 Needle valve V4 Open / close valve EV1, EV2 Solenoid valve S1, S2 Water level sensor

Claims (4)

The fixed side member and the rotation side member are provided, and the fixed side member and the rotation side member rotate relative to each other while being in sliding contact with each other, whereby an arc-shaped groove formed in the fixed side member and the rotation side member In the rotary valve configured to intermittently communicate with the formed communication hole,
The rotating side member is supported by a bearing,
A rotary valve characterized in that the stationary member is made of alumina ceramics and the rotating member is made of carbon ceramics.   The rotary valve according to claim 1, wherein the bearing is a thrust bearing. The fixed side member and the rotation side member are provided, and the fixed side member and the rotation side member rotate relative to each other while being in sliding contact with each other, whereby an arc-shaped groove formed in the fixed side member and the rotation side member In the rotary valve configured to intermittently communicate with the formed communication hole,
2. A rotary valve according to claim 1, wherein a liquid supply hole for supplying liquid to the sliding contact surfaces of the fixed side member and the rotary side member is formed in the fixed side member. 4. The rotary according to claim 3, wherein the liquid supply hole is connected to a liquid supply tank disposed above the liquid supply hole so that liquid can be supplied to the sliding contact surface with a water head difference. valve.

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