JP2005021852A - Centrifuge and its residual cake discharge device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a centrifuge equipped with a residual cake discharge device for discharging the cake remaining in a basket. <P>SOLUTION: A sucking tool 22 is arranged in this centrifuge, which can be shifted in the basket 10 between a retracting position and the finally advanced position. When the tool 22 exists at the finally advanced position, a suction port 22a arranged at the tip of the tool 22 is made to approach a filter 12 arranged on the inner periphery of the basket 10. A compressed gas is blown from a nozzle 28 toward the portion of the filter 12 to be opposed to the port 22a while evacuating the tool 22. The residual cake exfoliated by the compressed gas is sucked from the port 22a and discharged to the outside. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a horizontal centrifuge in which an axis of a basket is disposed in a horizontal direction.

  As shown in Patent Documents 1 to 3, a horizontal centrifuge includes a cylindrical peripheral wall portion in which a large number of permeation holes are formed, a bottom wall portion that closes one end in the axial direction of the peripheral wall portion, and the peripheral wall. A basket-shaped basket having an annular end wall protruding inward in the radial direction from the inner circumference of the other end in the axial direction of the portion and rotatably supported in a state where the axis is oriented in the horizontal direction; A filter disposed on the inner periphery of the peripheral wall portion of the basket and a rotation driving device that rotationally drives the basket. The stock solution supplied into the basket is separated from the liquid by centrifugal force generated by the rotation of the basket. Liquid removal treatment is performed to separate the cake (solid matter such as crystals).

  In a horizontal centrifuge, since the basket is arranged with its axis oriented horizontally, the thickness of the cake formed in the basket can be made uniform, and the vibration of the basket can be reduced. .

  In addition, when the basket is placed in the casing, the horizontal centrifuge can be configured to open and close the cover on the front surface of the casing in the horizontal direction, so that a drive source for opening and closing the cover is not required. The structure is simple.

  Further, since the basket is opened in the horizontal direction, there is an advantage that observation in the basket and cleaning work in the basket can be easily performed.

  In a centrifuge, in order to form a cake in a basket-shaped basket, a device for collecting the obtained cake is required. As shown in Patent Document 1, the applicant of the present application tilts the central axis of the basket at a certain angle with respect to the horizontal direction when collecting the cake, and directs the bottom wall of the basket obliquely downward. A centrifuge with improved cake recovery rate was proposed.

  In this centrifuge, after the cake is dried in the basket, the cake on the inner periphery of the basket is scraped off and collected in the lower part of the basket by a scraping blade disposed in the upper part of the basket. Then, the tip of the cake suction tube enters the cake at the bottom of the basket to suck the cake, and finally the tip of the suction tube is placed between the lowermost part of the peripheral wall portion of the inclined basket and the bottom wall portion of the basket. The cake is displaced to the final suction position set at a position close to the corner between them, and the cake collected at the final suction position is sucked and recovered efficiently.

In addition, as shown in Patent Document 2 and Patent Document 3, a cake scraping device for scraping the cake formed on the inner periphery of the basket is disposed in the upper portion of the basket, and from the opening of the basket to the basket. There is known a centrifuge in which a chute is inserted and a cake scraped by a cake scraping device is discharged to the outside through the chute.
Japanese Patent Laid-Open No. 9-253532 JP-A-5-200327 JP 2002-143722 A

  As described above, in the centrifuge, after separating the stock solution into a cake and a liquid component, the scraping blade of the cake scraping device is displaced toward the peripheral wall side of the basket, and is formed on the inner periphery of the filter. The cake is scraped and collected, but the filter is damaged when the scraping blade comes into contact with the filter. Therefore, the scraping blade can reach only a position of 3 to 5 mm before the filter. Therefore, after collecting the cake, a cake having a thickness of 3 to 5 mm remains on the inner periphery of the filter. If the next stock solution is drained while leaving the residual cake as it is, the filter is clogged by the residual cake and its function is lowered, so that the liquid cannot be drained well.

  Therefore, conventionally, as shown in Patent Document 3, after performing the cake scraping step with the scraping blade, the filter is washed, but the residual cake adhering to the filter is washed. In such a case, there is a problem that a part of the cake formed is wasted.

  In addition, a nozzle is arranged outside the peripheral wall portion of the basket, and the filter is vibrated by blowing compressed gas from the nozzle to the filter through a through-hole provided in the peripheral wall of the basket, and the cake adhering to the filter is screened off. Proposals have also been made, but the perforations provided in the peripheral wall of the basket are distributed at intervals, so that it is difficult to screen the residual cake even if compressed gas is blown through the perforations to the filter. is there. In particular, when a filter that is difficult to deform, such as a sintered metal filter or a multi-layered wire mesh filter configured by laminating a plurality of wire meshes, is used as a filter, the compressed cake can be used to screen out residual cake. It is difficult to apply the vibration of 1 to the filter.

  Therefore, it is conceivable that the residual cake is peeled off by blowing compressed gas from the inside of the basket to the residual cake. This method has been conventionally used in vertical centrifuges, but when this method is used in horizontal centrifuges, dust is blown off by compressed gas when the residual cake is dry. The cake rises in the basket, and a part of the cake leaks out of the basket and reaches a liquid collection case.

  The objective of this invention is providing the horizontal centrifuge which can collect | recover, without scattering the residual cake adhering to the filter of a horizontal centrifuge.

  A horizontal centrifuge has a cylindrical peripheral wall portion in which a large number of permeation holes are formed, a bottom wall portion that closes one end in the axial direction of the peripheral wall portion, and a radial direction from the inner periphery of the other axial end of the peripheral wall portion. A basket having an annular end wall projecting inwardly and rotatably supported in a state in which the central axis is substantially horizontal, and a filter disposed on the inner periphery of the peripheral wall portion of the basket, A rotation driving device for rotating the basket is provided, and the stock solution supplied into the basket is separated into a cake and a liquid component by a centrifugal force generated by the rotation of the basket.

  In the present invention, in order to give such a horizontal centrifuge a function of discharging the residual cake, when the residual cake attached to the filter is discharged, a suction tool having a suction port disposed at the front end facing the filter; A nozzle that blows compressed gas toward the portion of the filter facing the suction port, a vacuum suction device that sucks the suction tool so as to create a negative pressure, and a compressed gas supply device that supplies the compressed gas to the nozzle When the compressed gas is ejected from the nozzle with the suction port of the suction tool facing the filter, the residual cake attached to the filter is peeled off by the compressed gas and is sucked and discharged from the suction port. Configured to be

  In this case, the suction device, the vacuum suction device, the nozzle, and the compressed gas supply device constitute a residual cake discharge device.

  As mentioned above, when compressed gas is sprayed on the part where the suction port of the suction tool is facing, with the suction port of the suction tool close to the filter, the cake peeled off by the compressed gas is sucked into the suction tool as it is. Since it can be sucked from the mouth and discharged to the outside, the remaining cake can be recovered without being scattered.

  In a preferred aspect of the present invention, the suction tool is in a retracted position in which the suction tool is retracted radially inward from a position corresponding to the inner peripheral portion of the end wall of the basket, and in a state of being close to the peripheral wall portion. It is provided so that it can be displaced between the positions, and is configured such that the suction port is close to and opposed to the filter when disposed at the final advanced position.

  In another preferred aspect of the present invention, the suction tool drive shaft rotatably supported at a position eccentric with respect to the central axis of the basket with the axis parallel to the central axis of the basket and one end directed into the basket. In the basket, the tip has a slit-like suction port extending from the vicinity of the end wall to the vicinity of the bottom wall, and the rear end is connected to one end of the suction tool drive shaft for rotation of the suction tool drive shaft. A hollow suction tool that can be swung between the final advance position and the retreat position in the basket, and a suction tool drive shaft that rotationally drives the suction tool to reciprocate between the retreat position and the final advance position. Suction tool driving device, vacuum suction device for sucking the inside of the suction tool, nozzle for blowing compressed gas toward the part where the suction port of the filter faces, and compressed gas to the nozzle A compressed gas supply device is provided for supplying. In this case, when the suction tool is in the retracted position, the suction tool is retracted radially inward from the inner peripheral portion of the end wall of the basket, and when the final advance position is reached, the suction port is the inner peripheral surface of the filter. When the suction tool is positioned at the final advance position while rotating the basket in which the residual cake is attached to the filter, the compressed gas is ejected from the nozzle. The residual cake attached to the filter is peeled off by the compressed gas, and is sucked and discharged from the suction port.

  In the case of the above configuration, the residual cake discharge device is configured by the suction tool drive shaft, the suction tool, the suction tool drive device, the vacuum suction device, the nozzle, and the compressed gas supply device.

  When the suction tool is provided as described above, if a scraping blade extending over the entire length of the suction port is provided at the tip of the suction tool, the above suction tool can be used to discharge only the residual cake. In addition, the main cake produced in the basket can be collected.

  That is, if the scraping blade is provided as described above, the cake is scraped off with the scraping blade by rotating the suction tool toward the final advance position while rotating the basket in which the cake is formed. The cake thus scraped off can be collected by sucking it through the suction port. In addition, after collecting the main cake in this way, the suction tool is positioned at the final forward position while rotating the basket, and a vacuum is applied to the filter in a state where the residual cake is adhered while the suction tool is evacuated. The residual cake can be peeled off by ejecting the compressed gas from, and sucked and discharged from the suction port.

  In a preferred aspect of the present invention, the nozzle outlet is provided outside the suction port, and the compressed gas is blown from the rear side in the rotation direction of the basket toward the portion where the suction port of the filter faces. It is done.

  As described above, when the suction tool is connected to the suction tool drive shaft and the suction tool is turned by rotating the suction tool drive shaft, the suction tool drive shaft is configured to be hollow, and the suction tool drive shaft Is preferably communicated with the suction tool drive shaft so that the vacuum suction device sucks the suction tool through the suction tool drive shaft.

  If comprised in this way, since the suction tool drive shaft can be used also as piping for connecting the inside of a suction tool to a vacuum suction device, it can prevent that the structure of a centrifuge becomes complicated.

  In another preferred aspect of the present invention, the nozzle outlet is provided in a state where the nozzle is opened inside the suction tool.

  In this case, it is preferable that a skirt portion made of a flexible material such as rubber is attached to the peripheral portion of the suction port so as to close the gap between the suction port and the filter.

  As described above, according to the present invention, when discharging the residual cake adhered to the filter, the suction tool having a suction port disposed at the tip of the suction tool and the portion where the suction port of the filter is opposed to the filter. With the nozzle that blows the compressed gas and the suction port of the suction tool close to the filter, the cake separated by the compressed gas ejected from the nozzle is directly sucked from the suction port of the suction tool and discharged to the outside. Thus, there is an advantage that the remaining cake can be recovered without being scattered.

  In the present invention, when the suction tool is provided with a scraping blade, the cake formed in the basket can be sucked and discharged from the suction port while scraping with the scraping blade. The entire cake formed in the basket can be collected by suction from the suction port.

  Hereinafter, the best embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a side cross-sectional view showing an embodiment of a centrifuge to which the present invention is applied, taken along a vertical plane when viewed from the side, and FIG. 2 is an upper surface of a suction tool used in the centrifuge of FIG. FIG. 3 and FIG. 3 are front views showing a cross-section of a part of the suction tool.

  In FIG. 1, reference numeral 1 denotes an installation base, and 2 denotes a base frame disposed on the installation base 1 and fixed to the installation base with bolts or the like. A base plate 3 is fixed on the base frame 2, and a lower end of a frame plate 4 arranged so that the base plate 3 and the plate surface are orthogonal to each other is fixed to one end of the base plate 3. A bearing device 5 is supported on the frame plate 4, and the rotating shaft 6 is supported by the bearing device 5 so as to be rotatable in a state where its central axis is directed in the horizontal direction.

  One end of a cylindrical casing base portion 7a with the axis line oriented in the horizontal direction is fixed to the frame plate 4, and a cup-shaped casing cover 7b is attached to the other end of the casing base portion 7a so as to be freely opened and closed.

  The illustrated casing cover 7b includes a cover main body 7b1 formed so that its outer shape has a truncated cone shape, and an end plate 7b2 that closes the end portion on the small diameter side of the cover main body 7b1. The end on the radial side is attached to the other end of the casing base 7a via a hinge (not shown) with the rotation center axis oriented in the vertical direction.

  Therefore, the casing cover 7b has a horizontal direction between a closed position in which the opening of the casing base 7a is covered as shown in the drawing and an open position in which the opening of the casing base is opened to expose the basket. Can be rotated. A drain hole 7c is formed in the lower part of the casing base 7a for discharging the liquid discharged from the basket described later. In this example, the casing 7 that accommodates the basket is configured by the casing base 7a and the casing cover 7b.

  7d is a fixture for fixing the casing cover 7b in the closed position to the casing base 7a.

  One end of the rotating shaft 6 supported by the bearing device 5 is introduced into the casing 7 through a seal member attached to the frame plate 4, and the basket 10 is attached to one end of the rotating shaft introduced into the casing 7. . The other end of the rotating shaft 6 is led out from the end of the bearing device 5, and a pulley 11 is attached to the other end of the rotating shaft led out to the outside.

  The basket 10 protrudes radially inward from the inner periphery of the peripheral wall 10a, the bottom wall 10b provided to close one end of the peripheral wall 10a in the axial direction, and the other end of the peripheral wall 10a in the axial direction. The basket 10 has a ring-shaped end wall 10c provided so as to be connected to the rotating shaft 6 by connecting a boss 10d provided at the center of the bottom wall 10b to the rotary shaft 6. The casing is rotatably supported in the casing with the central axis oriented in the horizontal direction.

  A large number of permeation holes (not shown) are formed in the peripheral wall portion 10a of the basket in a state of being distributed substantially uniformly over the entire peripheral wall portion, and the inner periphery of the peripheral wall portion 10a is formed of a perforated plate and a metal mesh. A filter 12 composed of a laminate or the like is attached.

  An electric motor 15 that is a rotational drive source of the basket 10 is attached on the base plate 3, and a belt 17 is wound around a pulley 16 attached to a rotating shaft of the electric motor 15 and a pulley 11 attached to the rotating shaft 6. Has been.

  The electric motor 15, the pulleys 11 and 16, and the belt 17 constitute a rotational drive device 18 that rotationally drives the basket 10.

  A cover 19 that covers the bearing device 5 and the rotary drive device 18 is also attached to the base plate 3.

  A residual cake discharging device 20 which is a characteristic part of the centrifugal separator according to the present invention is attached to the lower part of the end plate 7b2 of the casing cover facing the end wall 10c of the basket 10.

  The residual cake recovery device 20 of this embodiment also serves as a cake recovery device that recovers the cake formed in the basket, with the axis parallel to the central axis of the basket 10 and one end directed into the basket 10. A suction tool drive shaft 21 that is rotatably supported at a position eccentric with respect to the central axis of the basket 10, and a rear end portion is connected to one end of the suction tool drive shaft 21, and the basket as the drive shaft 21 rotates. A suction tool 22 that can be swung between a final advance position and a retracted position within 10, and a suction that drives the suction tool drive shaft 21 to reciprocate between the retracting position and the final advanced position. It comprises a tool driving device 23 and a vacuum suction device 25 for sucking the inside of the suction tool 22.

  In the illustrated example, the axial center portion of the suction tool driving shaft 21 is a hollow portion, and the vacuum suction device 25 sucks the suction tool through the hollow portion in the suction driving shaft 21.

  The suction tool 22 has a slit-like suction port 22a (see FIG. 3) extending from the vicinity of the end wall 10c to the vicinity of the bottom wall portion 10b in the basket 10 along the longitudinal direction of the suction port 22a. A scraping blade 22b extending over the entire length of the suction port in the longitudinal direction is provided.

  Further, a delivery pipe 26 extending in the axial direction of the basket is provided near the tip of the suction tool 22, and this delivery pipe 26 is connected to a compressed gas supply source such as a compressor through a flexible compressed gas supply pipe 27. Has been. The delivery pipe 26 is provided with a number of nozzles 28 for blowing compressed gas toward a portion of the filter 12 facing the suction port 22a.

  More specifically, the suction tool drive shaft 21 is arranged at an eccentric position with respect to the center of the basket with the axis parallel to the central axis of the basket 10, as shown in FIG. In addition, a hollow portion 21a is provided in the axial center portion. The drive shaft 21 is rotatably supported by a bearing device 24 attached to the end plate 7b2 of the casing cover.

  The suction tool 22 has a slit-like suction port 22a extending from the vicinity of the basket end wall 10c to the vicinity of the bottom wall portion 10b and a scraping blade 22b extending over the entire length of the suction port 22a in the longitudinal direction. The front end member 22 </ b> A has a curved connecting pipe 22 </ b> B that connects the rear end of the front end member 22 </ b> A to one end of the drive shaft 21.

  The illustrated tip member 22A has a hollow horn-shaped main body portion 22A1 formed in a divergent shape from the rear end portion toward the front end portion side, and a bowl shape from the front end portion of the main body portion 22A1 to the rear side in the rotation direction of the basket. The terminal portion 22A2 that is curved is integrally provided, and the opening on the distal end side of the terminal portion 22A2 serves as a suction port 22a.

  Of the edge portions on both sides in the width direction of the suction port 22a, one edge portion located on the front side in the rotation direction of the basket (arrow CW direction in FIG. 3) is a peripheral wall of the basket more than the other edge portion. A scraping blade 22b is formed so as to protrude toward the portion side and extend over the entire length in the longitudinal direction of the suction port 22a by the one end edge portion.

  The connecting tube 22B that connects the rear end portion of the tip member 22A to one end of the suction tool drive shaft 21 is composed of a curved tube that is welded at one end to the rear end portion of the tip member 22A and communicated with the tip member. Yes. A flange 22B1 is formed at the other end of the connection pipe 22B, and this flange 22B1 is fastened by a bolt 30 to a flange 21b formed at one end of the suction tool drive shaft 21, so that the inside of the connection pipe 22B and the suction tool drive shaft 21 The hollow portion 21a is in communication.

  In the present invention, when the suction tool drive shaft 21 is rotated, the suction tool 22 is swung between a retracted position indicated by a chain line in FIG. 3 and a final forward position indicated by a solid line in FIG. When the size and shape of each part of the suction tool 22 are determined and the suction tool 22 is in the retracted position, the suction tool 22 is connected to the inner periphery 10c1 of the end wall 10c of the basket as shown by the chain line in FIG. When the suction tool 22 reaches the final advance position, the suction port 22a and the scraping blade 22b are close to the inner peripheral filter 12 of the peripheral wall portion of the basket. (A state where they face each other through a slight gap).

  In the present embodiment, as shown by a solid line in FIG. 3, when the suction tool 22 is in the final advance position, the scraping blade 22b and the edge 22c of the suction port 22a facing the scraping blade 22b Are arranged on both sides of a vertical plane OO including the central axis of the basket, and between the edge 22c and the filter 12 on the inner periphery of the basket, than the gap between the scraping blade 22b and the filter 12. The tip of the tip member 22A is formed so that a large gap g is formed.

  As shown in FIG. 1, the suction tool drive device 23 includes an electric motor 31 and a speed reducer 33 housed in a gear box 32 supported by an end of the bearing device 24. Is reduced by the speed reducer 33 and transmitted to the suction tool drive shaft 21 so that the suction tool drive shaft 21 is reciprocally rotated.

  The other end of the suction tool drive shaft 21 is connected to one end of a pipe 34 via a joint (not shown) that allows rotation of the drive shaft 21, and the other end of the pipe 34 is connected to the vacuum suction device 25. Connected to the suction port. The vacuum suction device 25 includes a vacuum pump and a cake collection container, and sucks cake from the suction port 22a of the suction tool by making the suction tool 22 have a negative pressure through the pipe 34 and the hollow portion of the drive shaft 21. Collect with.

  The delivery pipe 26 is attached to the distal end member 22A of the suction tool 22 via a support member 29. The pipe is provided with a number of nozzles 28, 28,... Aligned in the longitudinal direction of the suction port. The series of nozzles 28, 28,... Are provided in a state of being spaced apart from each other, and each gas outlet is outside the suction port and sucks from the rear side in the rotation direction of the basket 10. Through the gap g between the edge portion 22c of the port 22a and the filter 12, the filter suction port 22a is provided so as to blow a compressed gas to a portion facing it.

  A pipe joint 26a is provided on the part of the delivery pipe 26 opposite to the side where the nozzle is provided, and one end of a compressed gas supply pipe 27 having flexibility is connected to the joint 26a. The compressed gas supply pipe 27 passes through the end plate 7b2 of the casing 7 and is led out to the outside, and is connected to a compressed gas supply source 35 such as a compressor. In this example, compressed air is used as the compressed gas.

  Although not shown, the end plate 7b2 of the casing is further formed in the basket when a raw solution is supplied into the basket, a supply pipe for supplying the raw solution, a cleaning liquid supply pipe for supplying the cleaning liquid, and the raw solution is supplied into the basket. A liquid level detector (none of which is shown) for detecting the liquid level is attached.

  In the present embodiment, the suction tool drive shaft 21, the suction tool 22, and the vacuum suction device 25 constitute a cake recovery device that recovers the main cake generated in the basket. The cake recovery device and the delivery pipe The residual cake discharge device 20 is configured by the nozzle 26, the nozzle 28, the compressed gas supply pipe 27, and the compressed gas supply source 35.

  When performing the process of separating the stock solution into the liquid and cake using the centrifuge shown in FIG. 1, the stock solution is fed into the basket 10 through the feed pipe 35 while rotating the basket 10 at a predetermined rotational speed. Supply. When it is detected that the liquid level of the stock solution has reached the limit position by a liquid level detector (not shown) during the liquid supply process, the supply of the stock solution into the basket 10 is interrupted.

  The liquid component in the stock solution is discharged out of the basket through the filter 12 due to the centrifugal force generated by the rotation of the basket, and the cake contained in the stock solution is deposited on the inner periphery of the filter disposed on the inner periphery of the peripheral wall portion 10a of the basket 10. I will do it. The liquid discharged to the outside of the basket flows down in the casing 7 and is discharged to the outside from the drain hole 7c.

  The supply of the stock solution is resumed when it is detected that the liquid removal has progressed and the liquid level has fallen to a predetermined level, and the supply of the stock solution is interrupted again when it is detected that the liquid level has reached the limit level.

  When the above operation is repeated, the thickness of the cake layer formed on the inner periphery of the basket becomes thicker, and the time required for liquid removal becomes longer as the thickness of the cake layer increases. When the thickness of the cake layer becomes sufficiently thick and a state in which a decrease in the liquid level is not detected within a certain time occurs, the supply of the stock solution into the basket is stopped, and the liquid supply process ends. After the liquid supply process is completed, the basket 10 is increased to the rotational speed at the time of liquid removal, and the liquid is drained while maintaining the rotational speed for a predetermined liquid removal time experimentally obtained in advance.

  After the drainage time has elapsed, a washing process is carried out to wash the cake in the basket. In this cleaning step, the cleaning liquid is supplied into the basket through the cleaning liquid supply pipe while rotating the basket at a rotation speed suitable for cleaning, and the cake in the basket is cleaned with this cleaning liquid. After a certain washing time has elapsed, the basket is increased to the dewatering rotation speed, and the washing liquid contained in the cake is released from the cake.

  After the washing process is completed and liquid removal is performed, a cake collection process is performed for collecting the cake formed in the basket. In this process, the suction tool 22 is swung toward the peripheral wall portion side of the basket while rotating the basket 10 in one direction (rotation direction at the time of cake scraping, in this example, the direction of the arrow CW shown in FIG. 3) at a low speed. The scraping blade 22b at the tip is advanced into the cake formed in the basket 10.

  When the suction tool 22 is swung to the peripheral wall portion side of the basket while rotating the basket 10, the scraping blade 22b comes into contact with the cake and scrapes the cake. The scraped cake is sucked as it is from the suction port 22a and is discharged to the outside through the hollow portion in the suction tool drive shaft 21.

  Since the suction port 22a is provided so as to cover almost the whole of the basket in the axial direction, almost all cakes in the basket are collected by a simple operation of turning the suction tool 22 toward the final advance position. can do.

  The turning speed when turning the suction tool 22 toward the final forward position is related to the rotation speed of the basket so that the amount of cake to be scraped is kept to a level that does not clog the suction opening. Set the size appropriately.

  After collecting the main cake in the basket as described above, a step of discharging the residual cake attached to the filter 12 on the inner periphery of the basket 10 is performed. In this residual cake discharging step, with the suction tool 22 positioned at the final forward position, the rotational speed of the basket 10 is reduced to a speed lower than the rotational speed when the main cake is recovered, and the compressed gas supply source The compressed air is supplied from 35 to the delivery pipe 26 to eject the compressed air from the nozzle 28, and the suction tool 22 is sucked by the vacuum suction device 25.

  Since the compressed air ejected from the nozzle 28 is blown to the part of the filter 12 facing the suction port 22a, the residual cake attached to the part of the filter 12 facing the suction port is peeled off by the compressed air. It is done. The cake peeled off by the compressed air is sucked from the suction port 22a of the suction tool 22 that is opened as it is and sucked and discharged by the vacuum suction device 25, so that almost all dust is generated in the basket. And the residual cake can be discharged.

  In the above description, the suction port 22a and the scraping blade 22b of the suction tool are formed so as to be elongated in the axial direction of the basket, and a series of nozzles 28, 28,... Are arranged along the longitudinal direction of the suction port 22a. However, the suction port 22a and the scraping blade 22b are provided so as to extend from the vicinity of the end wall of the basket to the vicinity of the bottom wall (so as to cover almost the entire axial direction in the basket). What is necessary is just to be provided along the direction incline a little with respect to the axial direction of a basket.

  The series of operations described above controls the electric motor 15 that drives the basket, the valve that controls the supply of the stock solution to the liquid supply pipe, the electric motor 31 that rotationally drives the suction tool drive shaft 21, and the like to operate in a predetermined sequence. This can be done automatically.

  As described above, when the scraping blade 22b is provided adjacent to the suction port 22a and the cake scraped by the scraping blade 22b is sucked directly from the suction port 22a, the cake scraped by the scraping blade 22b By setting the approach speed of the scraping blade into the cake so that the amount does not become excessive (the turning speed of the suction tool 22 toward the final advance position), while preventing the suction port from being clogged with the cake, The main cake can be sucked and collected.

  Further, as described above, if the suction port 22a of the suction tool 22 is formed in a long and narrow slit shape, even if the moisture content of the cake is high, the entire suction port is not clogged by the cake, and a part of the suction port must be formed. Since air is in a circulating state, the suction port is prevented from being closed, and the cake can be collected smoothly.

  Further, as described above, the suction port of the suction tool is provided so as to extend from the vicinity of the end wall of the basket to the vicinity of the bottom wall portion, and a scraping blade is provided so as to extend over the entire length of the suction port. Since the suction port and the scraping blade can cover almost the entire axial direction in the basket, almost the entire main cake in the basket can be collected without tilting the basket.

  In the above description, after the cake is washed, the cake is scraped and collected by the suction tool 22 without performing the drying process. However, after the cake is dried, the suction tool is turned to the final advance position side. It is also possible to scrape and collect the cake, and then discharge the remaining cake.

  In the present invention, the scraping blade is provided at the tip of the suction tool together with the suction port 22a, and the cake scraped off by the scraping blade is sucked from the nearest suction port as it is and directed to the portion facing the suction port 22a of the filter. The residual cake is peeled off by the compressed gas blown out and the peeled residual cake is sucked in and collected from the suction port as it is, so even if the cake is dry, it can be passed through the suction tool without scattering the cake. Can be discharged and collected.

  In the above embodiment, the nozzle 28 is blown out of the suction port 22a so that the compressed gas is blown from the rear side in the rotation direction of the basket toward the portion where the filter suction port 22a faces. As shown in FIG. 4, each nozzle 28 is provided in a state of passing through the tip member 22 </ b> A of the suction tool 22, and the outlet of each nozzle 28 is filtered inside the suction tool 22. You may make it open toward the part facing 12 suction inlets 22a.

  If comprised in this way, since the cake peeled with the compressed gas injected from the nozzle 28 can be made difficult to scatter to the exterior of the suction tool 22, collection | recovery of a residual cake can be performed more reliably.

  In the above example, the residual cake discharge device 20 is configured to also serve as a cake recovery device that recovers the main cake (cake that is not a residual cake) formed in the basket. However, the residual cake discharge device 20 collects the residual cake. It is also possible to provide only means for collecting the main cake formed in the basket.

  When the residual cake discharge device is configured to collect only the residual cake, it is not necessary to consider collecting the cake scraped off by the scraping blade, so the residual cake scattered by the compressed gas is scattered. It is possible to adopt a configuration that emphasizes prevention.

  5 and 6 show a configuration example of a main part of the residual cake discharging device 20 'that only collects the residual cake. In these drawings, 22' denotes a retracted position and a final advanced position in the basket. It is a suction tool provided so that it can be displaced between. The suction tool 22 'includes a semi-cylindrical main body 22A1' having both ends closed by end plates 22A2 'and 22A3', and a tip end member 22A 'having a semi-cylindrical shape and a rear end portion of the end member 22A'. And a connecting pipe 22B 'having one end connected to the other end. The tip member 22A ′ is configured to open only in one direction, and the opening of the tip member 22A ′ serves as a suction port 22a ′. Similarly to the example shown in FIG. 1, the other end of the connection tube 22B ′ is connected to a suction tool drive shaft formed in a hollow shape and connected to a vacuum suction device through the hollow portion of the drive shaft.

  The suction tool 22 ′ is driven by a mechanism (not shown), and a retracted position where the suction tool 22 ′ is retracted radially inward from the inner peripheral portion of the end wall 10 c of the basket, and the suction port 22 a ′ of the tip member are filtered. 12 is displaced between the final forward position and the state close to 12.

  As shown in FIG. 6, the tip member 22A ′ is provided so as to extend linearly between a position close to the end wall 10c of the basket and a position close to the bottom wall 10b. A delivery pipe 26 'is disposed in the member 22A'.

  The delivery pipe 26 ′ is arranged in a state where the longitudinal direction thereof coincides with the longitudinal direction of the suction port 22 a ′ (opening portion of the tip member 22 A ′), and the delivery pipe 26 ′ has a large number arranged in the longitudinal direction of the suction port 22 a ′. Nozzles 28 ', 28', ... are provided. Each nozzle 28 ′ is provided in a state where its injection port faces a portion facing the suction port 22 a ′ of the filter 12.

  The delivery pipe 26 ′ is provided with a joint portion 26 a ′. The joint portion passes through the tip member 22 A ′ and is led out to the outside, and a compressed gas supply pipe 27 ′ is connected to the joint portion.

  Furthermore, in this example, in order to close the gap between the suction port 22a ′ of the tip member 22A ′ and the filter 12, a skirt portion 22C ′ made of a flexible material is attached to the peripheral portion of the suction port 22a ′.

  When the residual cake is discharged using the residual cake discharging device shown in FIGS. 5 and 6, the cake generated in the basket 10 is discharged by a discharging device (not shown) and then the basket is rotated at a sufficiently low speed. .., And evacuating the suction tool 22 ′ with a vacuum suction device, the compressed gas is blown from the nozzles 28 ′, 28 ′,... To the part facing the suction port 22 a ′ of the filter 12. Thereby, the residual cake adhering to the filter 12 is peeled, and the peeled residual cake is sucked and discharged through the connecting pipe 22B ′.

  As shown in FIGS. 5 and 6, when the skirt portion 22C ′ is attached so as to close the periphery of the suction port of the tip member of the suction tool and the filter, the cake peeled off by the compressed gas is removed from the tip member. It is possible to prevent leakage to the outside of the cake, so that the residual cake can be collected efficiently.

  In addition, if the vacuuming in the suction tool 22 ′ is performed with a sufficiently strong force, even if there is no skirt portion 22C ′, most of the cake separated by the compressed gas can be sucked and discharged, so the skirt portion 22C ′ It may be omitted.

  In the embodiment shown in FIGS. 5 and 6, the delivery pipe 26 ′ is arranged inside the tip member of the suction tool 22 ′. However, like the example shown in FIG. 4, the delivery pipe 26 ′ is placed in the tip member 22 </ b> A. The nozzle 28 'provided in the delivery pipe is provided in a state of penetrating the tip member 22A', and each nozzle is opened toward the portion where the suction port 22a 'of the filter 12 faces. You may do it.

  In the centrifuge according to the present invention, when a cake collecting device for collecting the main cake generated in the basket is provided separately from the residual cake discharging device, the configuration of the cake collecting device is arbitrary. For example, as shown in FIG. 7, the chute 40 is inserted into the basket 10 through the end plate 7 b 2 of the casing 7, and the cake scraped by the scraping blade 41 at the upper part of the basket is passed through the chute 40 to the outside. It is also possible to use a cake discharge device that discharges the cake.

  The residual cake discharging device 20 ′ shown in FIG. 7 corresponds to the residual cake discharging device 20 ′ used in the embodiment shown in FIGS. 1 to 3 except the scraping blade 20b.

  In FIG. 7, the vacuum suction device and the compressed gas supply source are not shown.

  In each of the above embodiments, the residual cake discharge device 20 ′ is arranged at the lower part of the basket. However, the position where the residual cake discharge device 20 ′ is arranged need not be the lower part of the basket, for example, the upper part in the basket. Alternatively, it may be arranged near the middle part in the vertical direction.

  In each of the above-described embodiments, the suction tool drive shaft 21 is formed in a hollow shape, and the connection pipe 22B of the suction tool is connected to the vacuum suction device through the hollow portion of the drive shaft 21, but the suction tool drive shaft 21 is used. The inside of the suction tool 22 may be connected to a vacuum suction device through a flexible pipe.

  In the above embodiment, the basket is accommodated in the casing, but the present invention can also be applied to a centrifugal separator of a type that does not accommodate the basket in the casing.

1 is a side cross-sectional view showing an embodiment of a centrifuge to which the present invention is applied, taken along a vertical plane when viewed from the side. It is the top view which showed the principal part of the residual cake discharge | emission apparatus used with the centrifuge of FIG. It is the front view which showed the principal part of the residual cake discharge | emission apparatus used with the centrifuge of FIG. It is the front view which showed the principal part of the residual cake discharge | emission apparatus used in other embodiment of this invention, partially cut. It is the cross-sectional view which showed the structure of the principal part of the residual cake discharge apparatus used by other embodiment of this invention. It is a front longitudinal cross-sectional view of the principal part of the residual cake discharge apparatus of embodiment of FIG. It is side surface sectional drawing which carried out the cross section along the perpendicular | vertical surface seeing further another embodiment of this invention from the side surface.

Explanation of symbols

2 Base frame 5 Bearing device 6 Rotating shaft 7 Casing 10 Basket 10a Peripheral wall 10b Bottom wall 10c End wall 12 Filter 20 Residual cake discharging device 21 Suction tool drive shaft 22 Suction tool 22a Suction port 22b Scraping blade 23 Suction tool drive Device 25 Vacuum suction device 26 Delivery pipe 27 Compressed gas supply pipe 28 Nozzle 35 Compressed gas supply source

Claims (8)

A cylindrical peripheral wall having a large number of transmission holes, a bottom wall that closes one end in the axial direction of the peripheral wall, and an annular shape that protrudes radially inward from the inner periphery of the other axial end of the peripheral wall A basket that has an end wall and is rotatably supported with the central axis oriented substantially in the horizontal direction, a filter disposed on the inner periphery of the peripheral wall of the basket, and a rotation that drives the basket to rotate In a centrifuge with a drive device,
A suction tool having a suction port at the tip disposed opposite to the filter when discharging the residual cake attached to the filter;
A nozzle that blows compressed gas toward a portion of the filter facing the suction port;
A vacuum suction device for suctioning the suction tool so as to make a negative pressure;
A compressed gas supply device for supplying compressed gas to the nozzle,
When compressed gas is ejected from the nozzle with the suction port facing the filter, the residual cake attached to the filter is peeled off by the compressed gas and is sucked and discharged from the suction port. That it is configured,
Centrifuge characterized by. A cylindrical peripheral wall having a large number of transmission holes, a bottom wall that closes one end in the axial direction of the peripheral wall, and an annular shape that protrudes radially inward from the inner periphery of the other axial end of the peripheral wall A basket that has an end wall and is rotatably supported with the central axis oriented substantially in the horizontal direction, a filter disposed on the inner periphery of the peripheral wall of the basket, and a rotation that drives the basket to rotate In a centrifuge with a drive device,
It is possible to displace between a retracted position that is retracted radially inward from a position corresponding to the inner peripheral portion of the end wall of the basket and a final forward position that is close to the peripheral wall portion. A suction tool provided at the tip of the suction port that is provided and is located in close proximity to the filter when disposed at the final forward position;
A nozzle that blows compressed gas toward a portion of the filter facing the suction port;
A vacuum suction device for suctioning the suction tool so as to make a negative pressure;
A compressed gas supply device for supplying compressed gas to the nozzle,
When the suction tool is positioned at the final forward position and the compressed gas is ejected from the nozzle, the residual cake attached to the filter is peeled off by the compressed gas and is sucked and discharged from the suction port. To be configured,
Centrifuge characterized by. A cylindrical peripheral wall having a large number of transmission holes, a bottom wall that closes one end in the axial direction of the peripheral wall, and an annular shape that protrudes radially inward from the inner periphery of the other axial end of the peripheral wall A basket that has an end wall and is rotatably supported with the central axis oriented substantially in the horizontal direction, a filter disposed on the inner periphery of the peripheral wall of the basket, and a rotation that drives the basket to rotate In a centrifuge with a drive device,
A suction tool drive shaft rotatably supported at a position eccentric with respect to the central axis of the basket with an axis parallel to the central axis of the basket and one end directed into the basket;
The suction tool drive shaft has a slit-like suction port extending from the vicinity of the end wall to the vicinity of the bottom wall portion in the basket at the front end, and a rear end portion connected to one end of the suction tool drive shaft. A hollow suction tool that can be swung between a final advance position and a retracted position in the basket as it rotates.
A suction tool drive device that rotationally drives the suction tool drive shaft so as to reciprocately rotate the suction tool between the retracted position and the final advance position;
A vacuum suction device for sucking the inside of the suction tool;
A nozzle that blows compressed gas toward a portion of the filter facing the suction port;
A compressed gas supply device for supplying a compressed gas to the nozzle;
Comprising
When the suction tool is in the retracted position, the suction tool is retracted radially inward from the inner peripheral portion of the end wall of the basket, and when the final advance position is reached, the suction port becomes the filter. It is provided to be in a state close to the inner peripheral surface of the
When the basket with the residual cake attached to the filter is rotated, the suction tool is positioned at the final advance position and the compressed gas is ejected from the nozzle. The residual cake attached to the substrate is peeled off and sucked and discharged from the suction port,
Centrifuge characterized by. A cylindrical peripheral wall portion having a large number of transmission holes, a bottom wall portion that closes one end of the peripheral wall portion in the axial direction, and an annular shape that protrudes radially inward from the inner periphery of the axial end of the peripheral wall portion. A basket that has an end wall and is rotatably supported with the central axis oriented substantially in the horizontal direction, a filter disposed on the inner periphery of the peripheral wall of the basket, and a rotation that drives the basket to rotate In a centrifuge with a drive device,
A suction tool drive shaft rotatably supported at a position eccentric with respect to the central axis of the basket with an axis parallel to the central axis of the basket and one end directed into the basket;
A slit-like suction port extending from the vicinity of the end wall to the vicinity of the bottom wall portion in the basket and a scraping blade extending over the entire length in the longitudinal direction of the suction port at the front end, and the rear end portion A hollow suction tool connected to one end of the suction tool drive shaft and swiveled between a final advance position and a retracted position in the basket as the suction tool drive shaft rotates;
A suction tool drive device that rotationally drives the suction tool drive shaft so as to reciprocately rotate the suction tool between the retracted position and the final advance position;
A vacuum suction device for sucking the inside of the suction tool;
A nozzle that blows compressed gas toward a portion of the filter facing the suction port;
A compressed gas supply device for supplying a compressed gas to the nozzle;
Comprising
The cake scraped by the scraping blade is sucked and collected from the suction port when the suction tool is turned toward the final forward position while rotating the basket in which the cake is formed. When the suction tool is positioned at the final advance position while rotating the nozzle, and the compressed gas is ejected from the nozzle to the filter in which the residual cake is attached, the residual cake is caused by the compressed gas. It is configured to be peeled off and sucked and discharged from the suction port,
Centrifuge characterized by. The suction tool drive shaft is configured to be hollow, and the hollow portion of the suction tool is communicated with the suction tool drive shaft,
The centrifuge according to claim 3 or 4, wherein the vacuum suction device is configured to suck the suction tool through the suction tool drive shaft. The nozzle outlet is provided so as to blow compressed gas from the rear side in the rotation direction of the basket toward the portion of the filter facing the suction port facing the outside of the suction port. Item 6. The centrifuge according to any one of Items 1 to 5. The centrifuge according to any one of claims 1 to 5, wherein the nozzle outlet is provided in a state where the outlet is opened inside the suction tool. The centrifuge according to claim 7, wherein a skirt portion made of a flexible material for closing a gap between the suction port and the filter is attached to a peripheral portion of the suction port.

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