JP6349604B1 - Centrifugal dehydrator - Google Patents

Abstract

A back pressure is stably applied while easily adjusting the back pressure applied to a dehydrated cake. A rotating body 2 having an outer body bowl 8 and an inner body screw provided with a blade member, a valve body 17 provided with an adjustable width of a discharge passage 27, and a width of the discharge passage 27. A group of disc springs 18 that apply elastic force to the valve body in a decreasing direction, and a cylindrical support body 20 that is arranged to support the opposite side of the valve body of the group of disc springs 18 in the axial direction; The valve body 17 has a conical portion 45 and a cylindrical portion 46, and the group of disc springs 18 has a plurality of circular disc springs 37 provided with an enlarged diameter portion around the enlarged diameter portion. The cylindrical portion 46 is inserted into the inner peripheral side of the first cylindrical member 46, the other end of the group of axial directions is in contact with the conical portion 45, one end of the group of axial directions is in contact with the support 20, and the disc spring 37 at one end is The surface of the enlarged diameter portion facing the one side in the axial direction is in contact with the support 20 and is in contact with one end of the disc spring 37 of the support 20. Sectional shape along the direction to provide a centrifugal dehydrator is semicircular. [Selection] Figure 2

Description

  The present invention relates to a centrifugal dehydration apparatus.

As a centrifugal dehydrator that separates solid and liquid using centrifugal force, centrifugal force is applied by rotation of the outer barrel bowl to perform solid-liquid separation, and heavy components containing solid and liquid components by the inner barrel screw, for example, A device for carrying out and discharging a dehydrated cake in a machine is known.
In such a centrifugal dehydration apparatus, dehydration of a dehydrated cake or the like is promoted by the self-weight pressurization by centrifugal force and the squeezing force of the discharge resistance simultaneously with the solid-liquid separation. In the dehydration by the squeezing force using the discharge resistance, for example, the discharge resistance is increased by reducing the flow passage area of the discharge port. That is, by making the discharge port narrow, a compacting action is given to the dewatered cake discharged from the discharge port (see, for example, Patent Document 1).

  Patent Document 1 discloses a mechanism for applying back pressure to the dewatered cake at the discharge port. The back pressure is applied by a member such as a back pressure adjusting body whose tip is formed in a conical shape with a tapered tip, and a spring that biases the back pressure adjusting body.

JP 2001-29842 A

  Incidentally, Patent Document 1 does not specifically disclose a member such as a spring that biases the back pressure adjusting body. In addition, there is a possibility that some problems may occur due to the installation of members such as springs, but if the countermeasures are not clarified by the specific configuration (type of spring, installation method, etc.), back pressure adjustment It may interfere with normal operation of the body or cause an error in setting the back pressure, which may adversely affect the stable operation of the device and the reduction of moisture content.

  An object of the present invention is to provide a centrifugal dehydrating apparatus that can easily apply a back pressure to a dehydrated cake while easily adjusting the back pressure applied to the dehydrated cake.

According to the first aspect of the present invention, the centrifugal dewatering device includes a cylindrical outer shell bowl to which a hydrated product is supplied, and a blade member that protrudes from the peripheral surface of the rotating drum housed in the outer shell bowl. An inner body screw for propelling the hydrated material in one axial direction, a rotating body that dehydrates using a centrifugal force while conveying the hydrated material, and is disposed coaxially with the rotating body, A valve body provided at an end in the axial direction of the outer shell bowl so as to be able to adjust the axial width of the drainage passage of the water content, and a direction in which the width is reduced by being arranged coaxially with the rotating body A group of disc springs that apply elastic force to the valve body, and a cylinder that is arranged coaxially with the rotating body and that is arranged to support the opposite side of the group of disc springs to the valve body in the axial direction. comprising a support in the form, the said valve body, said axial other side orientation the axial direction one- A slope whose diameter increases toward the side, a conical portion having a vertical surface facing said axial one side, the outer diameter is smaller than the maximum diameter of the conical portion is connected to one axial side of said conical part And the group of disc springs includes a plurality of circular disc springs having a diameter-expanding portion that increases in diameter toward the axial direction, and includes an inner portion of the diameter-expanding portion. The cylindrical portion is inserted on the circumferential side, the disc spring at the other axial end of the group of disc springs is in contact with the vertical surface of the conical portion , and the disc spring at one axial end of the group of disc springs The disc spring at one end is in contact with the disc spring at the one end of the support, and the surface facing the one side in the axial direction of the enlarged diameter portion is in contact with the support. a is the cross-sectional shape is semicircular when viewed from the circumferential edge portion extending in the circumferential direction in the axial direction other side Characterized in that there.

According to such a structure, an elastic force can be given to a valve body using a group of disc springs. Moreover, the elastic force given to a valve body can be easily changed by increase / decrease in the number of disk springs.
Furthermore, since the portion of the support that contacts the disc spring is formed in a semicircular shape, even if the contact angle changes at the location where the disc spring contacts the support due to expansion and contraction of the disc spring, the friction coefficient The contact area is always constant. Thereby, the compression force of a disc spring can be transmitted stably, and the deformation | transformation operation | movement of a disc spring can be made smooth.

  The group of disc springs may include a plurality of units in which a plurality of units each including a predetermined number of disc springs are arranged in series in the axial direction.

  The group of disc springs composed of a plurality of units may include a unit in which the front surfaces or the back surfaces of the disc springs are in contact with each other.

  According to such a configuration, the number of disc springs necessary for the group of disc springs can be reduced.

  The centrifugal dewatering device further includes a sliding cylinder connected to the outer cylinder bowl, and the rotating cylinder inserted through the inner periphery, the support is fixed to the sliding cylinder, It may be inserted through the sleeve into the inner peripheral side of the cylindrical portion of the valve body.

  According to such a configuration, the sliding between the valve body and the sliding cylinder is smoothed by the sliding of the valve body disposed via the sleeve on the outer peripheral side of the sliding cylinder. be able to.

  In the centrifugal dewatering device, the outer body bowl, the sliding cylinder, the valve body, the support body, and the group of disc springs rotate at a first speed, the rotating body rotates at a second speed, and the first speed May be faster than the second speed.

According to the present invention, an elastic force is applied to the valve body by using a group of disk springs. Therefore, the elastic force applied to the valve body can be easily changed by increasing or decreasing the number of disk springs.
In addition, since the contact point between the support and the disc spring is formed in a semicircular shape, even if the contact angle between the disc spring and the support changes due to expansion and contraction of the disc spring, the friction coefficient and the contact area Is always constant. Thereby, the compression force of a disc spring can be transmitted stably, and the deformation | transformation operation | movement of a disc spring can be made smooth.

It is sectional drawing of the centrifugal dehydration apparatus of embodiment of this invention. It is sectional drawing of the valve body vicinity of the centrifugal dehydration apparatus of embodiment of this invention. It is a perspective view of a disc spring of an embodiment of the present invention. It is a figure explaining the combination pattern of the unit which comprises a group of disc springs of embodiment of this invention. It is sectional drawing which shows the state which the valve body of embodiment of this invention closed and the diameter-expanded surface and the slope contacted. It is a figure explaining the effect by the shape of the support body of the embodiment of the present invention. It is a figure explaining the effect by the shape of the support body of an embodiment of the present invention, and is a figure explaining the contact area of a support body and a disc spring. It is a figure explaining the effect by the shape of the support of the embodiment of the present invention, and is a figure showing a comparative example. It is a figure explaining the effect by the shape of the support body of an embodiment of the present invention, and is a figure explaining the contact area of the support body of a comparative example, and a disc spring.

Hereinafter, a centrifugal dewatering apparatus 1 according to an embodiment of the present invention will be described in detail with reference to the drawings.
As shown in FIG. 1, the centrifugal dewatering device 1 is a so-called straight body type, and includes a rotating body 2 that is formed in a hollow shape and extends in the axial direction D, and the other axial side of the rotating body 2. A feed pipe 3 inserted inside from the end of D2, a casing 4 for housing the rotating body 2, a pair of support units 5 provided at both ends in the axial direction D of the rotating body 2, and the rotating body 2 And a drive unit 6 that is rotationally driven.

The rotating body 2 separates the hydrated material such as sludge supplied to the inside into a dehydrated cake and a separation liquid by dehydrating the material using a centrifugal force while being conveyed. The rotating body 2 includes a hollow cylindrical outer shell bowl 8 and an inner drum screw 22 that is accommodated in the outer shell bowl 8 and propels the hydrated material to one side D1 in the axial direction.
Centrifugal dehydration apparatus 1 separates the hydrated material introduced from the other axial side D2 (supply side) through the feed pipe 3 into a solid-liquid separation, and the dehydrated cake is disposed on one axial side D1 of the outer shell bowl 8, Discharge from the front side (discharge side) of the water content propulsion direction.

A water-containing material is supplied into the outer body bowl 8. The outer bowl 8 has a bowl main body 9 which is a cylindrical hollow casing, and a hollow outer cylinder rotating shaft 10 provided so as to protrude from both ends in the axial direction D of the bowl main body 9 to both sides. ing.
A separation liquid discharge hole 11 for discharging the separation liquid separated from the hydrated material is provided at the end of the bowl body 9 on the other axial side D2. A cake discharge hole 12 for discharging the dehydrated cake separated from the hydrated material is provided at the end of the bowl body 9 on the one axial side D1.

  On the inner peripheral surface of the bowl body 9, a protrusion 13 is formed adjacent to the cake discharge hole 12 and extending in the circumferential direction of the bowl body 9. As shown in FIG. 2, the protrusion 13 includes a reduced diameter surface 14 having a truncated cone shape that narrows the inner diameter of the bowl body 9 as the cross-sectional shape viewed from the circumferential direction moves toward the one axial side D <b> 1, and a reduced diameter It has a diameter-enlarged surface 15 (valve seat surface) which is connected to the surface 14 and has a truncated cone shape so that the inner diameter of the bowl main body 9 is increased toward the one axial side D1. In other words, the diameter-reduced surface 14 and the diameter-enlarged surface 15 of the ridge 13 have a triangular shape whose one side coincides with the inner peripheral surface of the bowl body 9 when viewed from the circumferential direction.

  As shown in FIG. 1, the outer shell bowl 8 is supported so that both ends of the outer shell rotating shaft 10 can be rotated around the shaft from below by the support unit 5 in a state where the outer shell rotating shaft 10 extends in the horizontal direction. Thus, the bowl body 9 is held at a predetermined height position from the installation surface F.

The inner cylinder screw 22 conveys the hydrated material inside the outer cylinder bowl 8 to the discharge side while stirring. The inner cylinder screw 22 includes a substantially cylindrical rotary drum 23 having a slightly larger diameter feed zone 24 formed in the center in the axial direction D, and a spiral projecting in the axial direction D projecting radially from the circumferential surface of the rotary drum 23. And a blade member 25 extending in a shape. A feed hole 26 communicating with the outer drum bowl 8 is formed through the feed zone 24 of the rotary drum 23.
The inner drum screw 22 is accommodated inside the outer drum bowl 8. Inner cylinder rotation shafts 16 projecting from both end portions in the axial direction D of the inner cylinder screw 22 are respectively inserted into the outer cylinder rotation shafts 10 of the outer cylinder bowl 8. The other axial side D2 of the inner cylinder rotation shaft 16 has a hollow structure. The pitch in the axial direction D of the blade member 25 can be arbitrarily changed. For example, the pitch can be a constant pitch or a gradually decreasing pitch.

  As shown in FIG. 2, the centrifugal dewatering device 1 is disposed coaxially with the rotating body 2, is provided with a valve body 17 that is movable in the axial direction D, and is disposed coaxially with the rotating body 2. On the other hand, a group of disc springs 18 that give elastic force to the other axial side D2 and a cylinder that is arranged coaxially with the rotating body 2 and supports the opposite side of the group 17 of disc springs 18 to the valve body 17 in the axial direction D. And a valve body 17, a group of disc springs 18, and a sliding cylinder 36 that supports the support body 20 from the radially inner side. The group of disc springs 18 includes a plurality of units 35 in which a plurality of units 35 are arranged in series in the axial direction D by combining a predetermined number (four in this embodiment) of disc springs 37 into one set. ing. For this reason, the group of disc springs 18 may be configured by only the same combination of units, or may include a plurality of units having different combinations.

  The sliding cylinder 36 is a member that is disposed on the outer peripheral side of the inner cylinder rotation shaft 16 and supports the valve body 17 so as to be slidable in the axial direction D. The sliding cylinder 36, the valve body 17, the group of disc springs 18, and the support body 20 rotate at the same rotational speed as the outer body bowl 8.

  As shown in FIG. 3, each disc spring 37 is a plurality of circular donut-shaped disc springs provided with a diameter-expanding portion 38 that increases in diameter in the axial direction D. That is, the disc spring 37 has a conical shape with a disk having a hole in the center, and the enlarged diameter portion 38 corresponds to this conical portion. An inner diameter d of the disc spring 37 is slightly larger than an outer diameter of a cylindrical portion 46 of the valve body 17 described later.

The sliding cylinder 36 is connected to the outer body bowl 8 and rotates together with the outer body bowl 8. As shown in FIG. 2, the sliding cylinder 36 is provided on the sliding cylinder main body 39 formed in a cylindrical shape coaxial with the rotating body 2 and on one side D1 in the axial direction of the sliding cylinder main body 39 and has a diameter. And a flange portion 40 formed to protrude outward in the direction and fixed to the end wall 19 of the outer bowl 8. The flange portion 40 can be fixed to the end wall 19 with a bolt 41, for example.
The sliding cylinder 36 is disposed on the radially outer side of the inner cylinder rotating shaft 16 via an oil seal 42. The sliding cylinder 36 and the rotating drum 23 can be rotated at different rotational speeds.

The support 20 is fixed to the outer peripheral surface 36 a of the sliding cylinder 36. The support 20 includes a pedestal 43 extending in the circumferential direction and a support body 44 provided on the other axial side D2 of the pedestal 43.
The pedestal 43 has an annular shape, and an inner peripheral surface facing the radially inner peripheral side is fixed to the outer peripheral surface 36 a of the sliding cylinder 36.

The support body 44 has a cylindrical shape and is arranged coaxially with the rotating body 2. The end of the support body 44 on one side D1 in the axial direction is fixed to the surface of the pedestal 43 facing the other side D2 in the axial direction over the circumferential direction.
The end portion on the other side D2 in the axial direction of the support body 44 is a portion that supports the end portion on the one side D1 in the axial direction of the group of disc springs 18. The support body 20 is formed so that the diameter of the support body 44 is about ½ of the sum of the inner diameter and the outer diameter of the disc spring 37. That is, the support body 20 is formed so that the end portion on the other axial side D <b> 2 of the support body main body 44 supports the vicinity of the radial center of the enlarged diameter portion 38 of the disc spring 37.
A portion where the support body 44 is in contact with the group of disc springs 18 has a semicircular cross section including the axis O. That is, the cross section seen from the circumferential direction of the edge portion on the other axial side D2 of the cylindrical support body 44 includes the outer peripheral surface of the support body 44, the inner peripheral surface of the support body 44, and the support body. 44 and an arcuate surface that smoothly connects the outer peripheral surface of 44 and the inner peripheral surface of the support body 44.

The valve body 17 has a conical portion 45 whose diameter increases toward the one side D1 in the axial direction, and a cylindrical portion 46 whose outer diameter is smaller than the maximum diameter of the conical portion 45 and is connected to the one side D1 in the axial direction of the conical portion 45. And have.
The conical portion 45 has a slope 21 that is a surface facing the other axial side D2, and a vertical surface that faces the one axial side D1 and is orthogonal to the axis O. The inclined surface 21 of the conical portion 45 increases in diameter toward the one axial side D1. The angle of the inclined surface 21 is equal to the angle of the enlarged diameter surface 15 of the protrusion 13 of the bowl body 9. That is, the conical portion 45 of the valve body 17 is formed so that the inclined surface 21 and the diameter-enlarged surface 15 are in surface contact by moving the valve body 17 to the other axial side D2. Thereby, the enlarged diameter surface 15 functions as a valve seat surface of the valve body 17.
The vertical surface of the conical portion 45 functions as a receiving surface for transmitting the elastic force of the group of disc springs 18 as back pressure.

A sleeve 47 is fixed to the inner peripheral surface of the cylindrical portion 46. The sleeve 47 facilitates sliding between the cylindrical portion 46 of the valve body 17 and the sliding cylinder 36. The sleeve 47 is formed of a material suitable for a plain bearing such as copper and having good wear characteristics.
A seal member 48 that seals between the inner peripheral surface of the conical portion 45 and the outer peripheral surface of the sliding cylinder 36 is provided on the inner peripheral surface of the conical portion 45. As the seal member 48, for example, an O-ring can be employed.

A cake discharge passage 27 that squeezes the dehydrated cake toward the cake discharge hole 12 is formed between the enlarged diameter surface 15 of the bowl body 9 and the conical portion 45 of the valve body 17. By a biasing force acting on the valve body 17 by the group of disc springs 18, the gap G <b> 1 between the enlarged diameter surface 15 and the inclined surface 21 of the conical portion 45 varies depending on the pressure applied to the valve body 17. It varies depending on the thickness of the disc spring 18. The valve body 17 is given an elastic force in a direction to reduce the width of the cake discharge passage 27.
In other words, the width of the cake discharge passage 27 (cross-sectional area perpendicular to the axial direction D of the cake discharge passage 27) varies according to the pressure of the dewatered cake applied to the valve body 17. The width in the axial direction D of the cake discharge passage 27 is adjusted by sliding the valve body 17 on the sliding cylinder 36 in the axial direction D.

  As shown in FIG. 1, the feed pipe 3 is for supplying a hydrated material to the rotating body 2. The feed pipe 3 is a hollow pipe member that is open at both ends, and is inserted into the inner cylinder rotating shaft 16 of the inner cylinder screw 22 from the end portion on the other axial side D2 of the rotating body 2, and one end of the feed pipe 3 is connected to the rotating cylinder. 23 feed zones 24 have been reached. On the other hand, the other end of the feed pipe 3 protruding from the end portion on the other axial side D <b> 2 of the rotating body 2 is supported by the support unit 5.

The casing 4 accommodates the outer shell bowl 8 and collects the dehydrated cake and the separated liquid discharged from the outer shell bowl 8. The casing 4 is a hollow casing, and a separation liquid chute 28 for discharging the separation liquid recovered from the outer shell bowl 8 to the outside is provided at the end of the casing 4 on the other axial side D2. Yes. A cake chute 29 for discharging the dewatered cake collected from the outer body bowl 8 is provided at the end of the casing 4 on the one axial side D1.

  The support unit 5 is a unit for rotatably supporting the rotating body 2 at both ends in the axial direction D. The support unit 5 includes a supply-side support unit 30 that supports an end portion on the other axial side D2 of the rotating body 2, and a discharge-side support unit 31 that supports an end portion on the one axial side D1 of the rotating body 2. Has been.

  The drive unit 6 is configured to rotationally drive the outer body bowl 8 and the inner body screw 22 constituting the rotating body 2 at different speeds. The drive unit 6 includes a motor 32 as a drive source, a belt transmission mechanism 33 that transmits the rotational driving force of the motor 32 to the outer body bowl 8, a hydraulic differential speed device 34 that rotationally drives the inner body screw 22, have. The operation of the motor 32 is controlled by a control device (not shown).

By controlling the speed difference between the rotational speeds of the outer shell bowl 8 and the inner shell screw 22, if a hydrate is deposited in the outer shell bowl 8, a centrifugal effect is given to the hydrated material for a longer time. Therefore, the moisture content of the hydrated product can be further reduced.
In the centrifugal dehydrator 1 of the present embodiment, the outer body bowl 8, the sliding cylinder 36, the valve body 17, the support body 20, and the group of disc springs 18 rotate at the first speed, and the rotating body 23 is the second. Rotate at a speed of.
The first speed is faster than the second speed.

  In this embodiment, the control for keeping the rotational torque of the inner drum screw 22 constant is performed, but instead, the control for keeping the speed difference between the rotational speeds of the outer shell bowl 8 and the inner drum screw 22 constant. You may go.

Next, a combination pattern of the group of disc springs 18 will be described. The group of disc springs 18 can obtain various load characteristics depending on the combination.
The group of disc springs 18 is configured by arranging a plurality of units 35 in the axial direction D, each unit 35 having a predetermined number of disc springs 37 as one set. Although the predetermined number is described here as four, it can be appropriately changed according to the design, and may be two, three, or five or more.
As shown in FIG. 4, the units 35 can be combined in various patterns. Further, a plurality of units having the same arrangement (same type units) may be arranged, or a plurality of units having different arrangements (different types of units) may be mixed and arranged. For example, a plurality of second units 35B in FIG. 4B may be combined to form a group of disc springs 18 with only the same type of units, or the first unit 35A in FIG. A group of disc springs 18 may be configured by combining a plurality of different units of the second unit 35B of b).

  As shown in FIG. 4A, the first unit 35 </ b> A is a unit in which a pair of disc springs 37 in which the back surfaces 37 b of the disc springs 37 are in contact with each other are arranged in series in the axial direction D.

  As shown in FIG. 4B, the second unit 35 </ b> B is a unit in which a pair of disc springs 37 in which the surfaces 37 a of the disc springs 37 are in contact with each other are arranged in series in the axial direction D.

  As shown in FIG. 4C, the third unit 35C has a disc spring 37 so that the front surface 37a and the back surface 37b are further in contact with both sides of the two disc springs 37 in which the back surfaces 37b are in contact with each other. It is the unit which piled up.

  As shown in FIG. 4D, the fourth unit 35D has a disc spring 37 so that the front surface 37a and the back surface 37b are further in contact with both sides of the two disc springs 37 in which the front surfaces 37a are in contact with each other. Are unit 35.

  As shown in FIG. 4E, the fifth unit 35E is a unit 35 in which four disc springs 37 are stacked in the same direction.

The above-described units 35 </ b> A to 35 </ b> E can be appropriately selected according to required load characteristics and the distance between the support 20 and the conical portion 45 of the valve body 17.
For example, the number of disc springs 37 required for the group of disc springs 18 can be reduced by using a unit in which the front surfaces 37a or the back surfaces 37b of the disc springs 37 are in contact with each other as in the first unit 35A. it can.

In the straight body type centrifugal dewatering device 1 configured as described above, when the outer body bowl 8 and the inner body screw 22 are rotationally driven by the drive unit 6 at different rotational speeds, water content such as sludge is fed. It is supplied to the feed zone 24 of the rotary drum 23 through the pipe 3. Then, the hydrated product is moved from the feed zone 24 to the outer shell bowl 8 through the supply hole 26 by receiving a centrifugal force.
Thereafter, the hydrated product is separated from the separated water and dehydrated by the centrifugal effect while being transported from the supply side to the discharge side by the blade member 25 of the inner barrel screw 22 due to the differential speed between the outer barrel bowl 8 and the inner barrel screw 22. Separated into cakes. Then, the separation liquid is discharged from the separation liquid chute 28 to the outside of the apparatus through the separation liquid discharge hole 11.

  A pressing force (back pressure) resulting from the discharge resistance is applied to the dehydrated cake in the axial direction D by the valve body 17 in the process of being conveyed and discharged. In other words, the dehydrated cake conveyed toward the one axial side D <b> 1 by the blade member 25 of the inner body screw 22 is given resistance by hitting the valve body 17 and pressing the valve body 17.

  As the water content of the dewatered cake decreases, the pressing force of the dewatered cake due to the driving force of the inner barrel screw 22 increases. When the pressing force of the dehydrated cake becomes larger than the discharge resistance by the group of disc springs 18, the group of disc springs 18 that support the valve body 17 are compressed, and the cake discharge passage 27 is formed. That is, the cake discharge passage 27 as shown in FIG. 2 is formed from the state in which the valve body 17 is closed as shown in FIG. 5 and the enlarged diameter surface 15 and the inclined surface 21 are in surface contact. As a result, the dehydrated cake is discharged from the cake chute 29 to the outside of the apparatus through the cake discharge passage 27 through the cake discharge passage 12.

Here, the spring constant and the number of the disc springs 37 will be described.
The spring constant and the number of the disc springs 37 are determined based on the specifications of the centrifugal dehydrator 1. For example, when the processing amount per hour of the centrifugal dehydrator 1 is 50 m ³ , it is determined based on the pressing force of the dewatering cake during the processing of the water content of this processing amount, that is, at the rated operation.
Specifically, during rated operation, the distance G1 between the enlarged diameter surface 15 and the inclined surface 21 is about 1/3 of the distance G2 between the inner peripheral surface of the bowl body 9 and the outer peripheral surface of the rotating drum 23 (hereinafter referred to as a standard interval). The number of spring constants and the number are selected.
That is, the spring constant and the number of the disc springs 37 are balanced so that the overall elastic force of the group of disc springs 18 and the pressing force of the dehydrated cake during the rated operation are balanced with the cake discharge passage 27 being at a standard interval. Selected.

Here, when the moisture content of the dehydrated cake further decreases, the pressing force of the dehydrated cake further increases, the interval G1 becomes larger than the standard interval, and the area of the cake discharge passage 27 increases. By increasing the area of the cake discharge passage 27, more dehydrated cake is discharged, and the residence time of the dehydrated cake is shortened. As a result, the moisture content of the dehydrated cake returns from the low state to the high state, that is, the original state.
Further, when the moisture content of the dehydrated cake increases, the pressing force of the dehydrated cake decreases, the interval G1 becomes smaller than the standard interval, and the area of the cake discharge passage 27 decreases. By reducing the area of the cake discharge passage 27, the discharge amount of the dehydrated cake is also reduced, and the residence time of the dehydrated cake is lengthened. Thereby, the moisture content of the dehydrated cake returns from the high state to the low state, that is, the original state.
That is, the residence time according to the moisture content of the dehydrated cake becomes a minimum, and the fluctuation of the moisture content of the dehydrated cake is minimized.

In addition, if the hydrated material contains fibers or crystals, the fibers or crystals may be deposited in the cake discharge passage 27. In this case, the area of the cake discharge passage 27 is temporarily reduced, the discharge resistance is increased, the internal pressure is increased, and the force for pressing the valve element 17 is increased. At this time, the valve element 17 moves backward in the axial direction one side D1 in accordance with the magnitude of the increased force, and the area of the cake discharge passage 27 increases. That is, the width G1 of the cake discharge passage 27 is widened because the gap G1 between the enlarged diameter surface 15 and the slope 21 is larger than the standard gap. As a result, the fiber and crystals accumulated in the cake discharge passage 27 are removed.
When the deposits are removed, the area of the cake discharge passage 27 returns to the standard interval by the elastic force of the group of disc springs 18.

Next, the effect by the shape of the support body 20 of this embodiment is demonstrated.
As described above, the support body 44 of the support 20 of this embodiment has a cylindrical shape. The cross-sectional shape including the end portion on the other axial side D <b> 2 of the support body 44, that is, the axis O of the edge that contacts the disc spring 37, is a semicircular shape.
As shown in FIG. 6, the support body 20 supports the disc spring 37 from the axial direction one side D1. When the disc spring 37 is deformed from the state shown in FIG. 6A to the compressed state as shown in FIG. 6B, the contact angle between the disc spring 37 and the support 20 changes.
That is, the angle formed by the axis O at the contact point C1 and the enlarged diameter portion 38 (disc spring 37) and the angle formed by the axis O at the contact point C2 and the enlarged diameter portion 38 (disc spring 37) change. As shown in FIG. 7, the contact points C1 and C2 move and the contact angle also changes. Here, at the contact points C1 and C2, the support 20 is slightly elastically deformed, so that the disc spring 37 and the support 20 are in surface contact. At this time, when the cross-sectional shape including the axis O of the support 20 is a semicircular shape, the contact area between the disc spring 37 and the support 20 does not change.

Next, as a comparative example, as shown in FIG. 8, the cross-sectional shape including the axis O of the support body 44C is rectangular, that is, the outer peripheral surface F1 of the support body 44C and the other axial side D2 of the support body 44C. The case where the shape is such that the surface F <b> 2 facing the surface is orthogonal to the surface will be described.
In this case as well, the contact angle between the disc spring 37 and the support 20C changes as the disc spring 37 is deformed from the state shown in FIG. 8A to the state shown in FIG. 8B. Here, at the contact points C21 and C22, the support 20 is slightly elastically deformed, so that the disc spring 37 and the support 20 are in surface contact. At this time, when the cross-sectional shape including the axis O of the support 20C is rectangular, the contact areas S21 and S22 between the disc spring 37 and the support 20C change.

  Thus, the disc spring 37 is deformed and the contact angle with the support 20C is changed, whereby the transmission of the compressive force of the disc spring 37 becomes unstable, and consequently the back pressure becomes unstable. Further, when the disc spring 37 is deformed, the ridgeline between the outer peripheral surface F1 of the support body 44C and the surface F2 facing the other axial side D2 slides while contacting the disc spring 37, so that the friction is large. As a result, thinning due to friction occurs on the support body 44C side, and the deforming operation of the disc spring 37 is not smooth.

  According to the above embodiment, the portion of the support 20 that contacts the disc spring 37 is formed in a semicircular shape, so that the contact of the portion where the disc spring 37 and the support 20 are in contact by the expansion and contraction of the disc spring 37. Even if the angle changes, the friction coefficient and the contact area are always constant. As a result, when the disc spring 37 is deformed, the friction between the disc spring 37 and the support 20 is reduced, thinning due to the friction on the support 20 side is prevented, and the disc spring 37 can be smoothly deformed. it can. Thereby, the compressive force of the disc spring 37 can be stably transmitted to the valve body 17, and the back pressure by the disc spring 37 can be stabilized. Moreover, the deformation | transformation operation | movement of the disc spring 37 can be made smooth.

In addition, the centrifugal dehydrator 1 can be manufactured at a lower cost by adopting the disc spring 37 as a member that gives the elastic force to the valve body 17.
Further, since the disc spring 37 is installed so that the cylindrical portion 46 of the valve body 17 is fitted to the inner diameter surface, the size can be reduced. Moreover, since it does not contact parts (for example, the rotating drum 23) which have a rotational speed difference with the disc spring 37 itself, wear can be prevented.

Further, since the valve body 17 includes the conical portion 45 and the cylindrical portion 46, the valve body 17 has a sufficient length in the axial direction D and can be prevented from moving in directions other than the axial direction D. Thereby, for example, even if the discharge pressure is biased, the width of the cake discharge passage 27 becomes uniform at any position in the circumferential direction, and the water-containing material can be discharged uniformly.
Further, since the hydrated material can be discharged evenly, abnormal vibration due to unbalance of the weight inside the outer bowl 8 can be prevented. That is, it is possible to prevent the water content in the cake discharge passage 27 from becoming uneven in the circumferential direction, thereby adversely affecting the operation performance of the centrifugal dehydrator 1.

  Although the embodiments of the present invention have been described in detail with reference to the drawings, the configurations and combinations of the embodiments in the embodiments are examples, and the addition and omission of configurations are within the scope not departing from the gist of the present invention. , Substitutions, and other changes are possible. Further, the present invention is not limited by the embodiments, and is limited only by the scope of the claims.

DESCRIPTION OF SYMBOLS 1 Centrifugal dehydrator 2 Rotating body 3 Feed pipe 4 Casing 5 Support unit 6 Drive unit 8 Outer trunk bowl 9 Bowl body 10 Outer trunk rotating shaft 11 Separation liquid discharge hole 12 Cake discharge hole 13 Projection 14 Reduced diameter surface 15 Expanded surface DESCRIPTION OF SYMBOLS 16 Inner cylinder rotating shaft 17 Valve body 18 A group of disc spring 19 End wall 20 Support body 21 Slope 22 Inner cylinder screw 23 Rotating cylinder 24 Feed zone 25 Blade member 26 Supply hole 27 Cake discharge passage 28 Separation liquid chute 29 Cake chute 30 Supply side support unit 31 Discharge side support unit 32 Motor 33 Belt transmission mechanism 34 Differential speed device 35 Unit 36 Sliding cylinder 37 Belleville spring 38 Diameter expansion part 39 Sliding cylinder body 40 Flange part 41 Bolt 42 Oil seal 43 Base part 44 Support body 45 Conical part 46 Cylindrical part 47 Sleeve 8 sealing member D axis direction D1 in one axial direction D2 opposite axial O axis

Claims (5)

A cylindrical outer body bowl to which hydrated material is supplied, and an inner body screw provided with a blade member projecting from the peripheral surface of a rotating drum accommodated in the outer body bowl, and propelling the hydrated material to one side in the axial direction A rotating body that dehydrates using centrifugal force while conveying the hydrated material,
A valve body that is arranged coaxially with the rotating body and is provided at an axial end of the outer body bowl so as to be adjustable in the axial width of the drainage passage of the hydrated material;
A group of disc springs arranged coaxially with the rotating body and imparting elastic force to the valve body in a direction to reduce the width;
A cylindrical support disposed coaxially with the rotating body and disposed so as to support the side of the group of disc springs opposite the valve body in the axial direction;
The valve body has a conical portion having a slope that expands as it faces the other side in the axial direction and toward the one side in the axial direction, and a vertical surface that faces the one side in the axial direction ,
A cylindrical portion having an outer diameter smaller than the maximum diameter of the conical portion and connected to one axial side of the conical portion;
The group of disc springs has a plurality of circular disc springs provided with a diameter-expanding portion that expands in diameter toward the axial direction, and the cylindrical portion is inserted on the inner peripheral side of the diameter-expanding portion, The disc spring at the other end in the axial direction of the group of disc springs is in contact with the vertical surface of the conical portion , and the disc spring at one end in the axial direction of the group of disc springs is in contact with the support. ,
The disk spring at the one end is in contact with the support body at a surface facing the one axial side of the enlarged diameter portion,
Centrifugal dehydration characterized in that the cross-sectional shape seen from the circumferential direction of the edge portion extending in the circumferential direction on the other side in the axial direction is a semicircular shape in contact with the disc spring at the one end of the support body apparatus.   The centrifuge according to claim 1, wherein the group of disc springs includes a plurality of units in which a plurality of units each including a predetermined number of disc springs are arranged in series in the axial direction. Dehydration device.   The centrifugal dehydration apparatus according to claim 2, wherein the group of disc springs configured by the plurality of units includes a unit in which the front surfaces or the back surfaces of the disc springs are in contact with each other. A sliding cylinder connected to the outer body bowl, wherein the rotating body is inserted into the inner peripheral side;
The support is fixed to the sliding cylinder,
The centrifugal dewatering device according to any one of claims 1 to 3, wherein the sliding cylinder is inserted into an inner peripheral side of a cylindrical portion of the valve body through a sleeve. The outer body bowl, the sliding cylinder, the valve body, the support, and the group of disc springs rotate at a first speed, and the rotating body rotates at a second speed,
The centrifugal dehydration apparatus according to claim 4, wherein the first speed is faster than the second speed.

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