JP2018153768A - Stirring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stirring device that can thin a film of process liquid to a proper film thickness by flatting with a blade.SOLUTION: In a stirring device, a blade 26 is attached to an arm 23 provided to a spindle 22 disposed inside a heat transfer barrel, via a connection part 24. The blade 26 can freely oscillate about a pin 32 parallel to the spindle 22 by the connection part 24. A maximum radius L1 of a rotational trajectory of a projection 34 provided to a tip of the blade 26 about the spindle is larger than a maximum radius L1 to an inner peripheral surface 11a from a rotation center of the spindle 22.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a stirring device.

  A stirring device for concentrating and drying the treatment liquid is known. The stirring device spreads the processing liquid on the inner peripheral surface of the heated heat transfer cylinder to form a thin film. Heat is transferred by a cylindrical heat transfer cylinder and steam around the heat transfer cylinder. A jacket for heating the drum, a main shaft disposed inside the heat transfer drum, and a blade (stirring blade) that rotates with the main shaft are provided. The blade has a tip formed linearly, and is arranged so that the tip does not contact the inner peripheral surface of the heat transfer cylinder, that is, a clearance is formed between the blade and the inner peripheral surface.

  In the stirring device, the blade is rotated together with the main shaft, and the processing liquid flowing down the inner peripheral surface of the heat transfer cylinder is spread and thinned by the blade. By thinning the treatment liquid in this way, the heat transfer efficiency is increased and evaporation is promoted. In addition, since the blade can suppress the treatment liquid from sticking to the heat transfer surface, it is also possible to use a high-viscosity liquid as the treatment liquid. Concentration of food raw materials, pulverization, and removal of solvent from the polymer solution It is used for recovery, concentration of waste liquid, and powdering.

  There is also known a stirring device in which a blade is supported so as to be swingable about an axis parallel to the main axis (for example, Patent Documents 1 to 3). This swingable blade rotates around the main axis with its tip close to the inner peripheral surface by centrifugal force due to rotation around the main axis.

Japanese Patent No. 3001007 Japanese Patent No. 2576911 Japanese Unexamined Patent Publication No. 63-72301

  By the way, eliminating the displacement between the shaft center of the heat transfer cylinder and the rotational position of the main shaft, and making sure that the cross section of the inner peripheral surface of the heat transfer cylinder is not deviated from a perfect circle are not particularly distorted. It is extremely difficult for a large-scale agitator intended for commercial production. The displacement between the shaft center of the heat transfer cylinder and the rotational position of the main shaft and the distortion of the heat transfer cylinder cause the clearance between the blade and the inner peripheral surface of the heat transfer cylinder during the rotation of the blade around the main axis. The variation in clearance causes fluctuations in the thickness of the thin film of the treatment liquid formed on the inner peripheral surface, resulting in problems such as failure to obtain the desired evaporation rate and low evaporation rate. It was.

  This invention is made | formed in view of the said situation, and it aims at providing the stirring apparatus which can make a process liquid thin into an appropriate film thickness by spreading with a braid | blade.

  The stirring device of the present invention is a cylindrical heat transfer drum, a main shaft disposed in the heat transfer drum, is attached to the main shaft, and moves along the inner peripheral surface of the heat transfer drum by rotating together with the main shaft. A blade that forms a thin film of a processing solution on an inner peripheral surface, and a connecting portion that connects the blade and the main shaft by making the tip of the blade movable in a radial direction around the main shaft, and the tip of the blade around the main shaft The maximum radius of a part or all of the rotation locus is larger than the maximum distance from the center of rotation of the main shaft to the inner peripheral surface.

  According to the present invention, even if the rotational position of the shaft center of the heat transfer cylinder and the rotational position of the main shaft are shifted or the heat transfer cylinder is distorted, part or all of the blade tip contacts the inner peripheral surface of the heat transfer cylinder. Therefore, the processing liquid can be thinned to an appropriate film thickness by spreading with a blade.

It is sectional drawing which shows the stirring apparatus of 1st Embodiment. It is a disassembled perspective view which shows the structure of a connection part. It is explanatory drawing which shows the relationship between the rotation radius of the protrusion part of a braid | blade, and the distance from the rotation center of a main axis | shaft to an internal peripheral surface. It is explanatory drawing which shows the state which the blade contacted the internal peripheral surface. It is explanatory drawing which shows the state which the braid | blade rotated around the axis | shaft perpendicular | vertical to the surface which the front-end | tip of a braid | blade and the rocking | fluctuation axis | shaft make. It is explanatory drawing which shows the example which provided four protrusion parts in the front-end | tip of a braid | blade. It is sectional drawing which shows the stirring apparatus which arranged the braid | blade of small size in the up-down direction. It is a perspective view which shows the example of the connection part of a small size braid | blade. It is a perspective view which shows 2nd Embodiment which urged | biased the braid | blade with the torsion spring. It is explanatory drawing which shows the contact state of the braid | blade in FIG. 9, and an internal peripheral surface. It is a perspective view which shows the example which urged | biased the braid | blade with the leaf | plate spring. It is explanatory drawing which shows the contact state of the braid | blade in FIG. 11, and an internal peripheral surface. It is a perspective view which shows the example which urged | biased the braid | blade with the compression spring. It is explanatory drawing which shows the contact state of the braid | blade in FIG. 13, and an internal peripheral surface. It is explanatory drawing which shows the contact state of the braid | blade and inner peripheral surface in the example which set the clearance to 0. It is explanatory drawing which shows the contact state of the braid | blade and an internal peripheral surface in the example which set the clearance to 0 with the small sized braid | blade. It is a perspective view which shows the braid | blade made freely swingable by the elasticity of braid | blade itself. It is explanatory drawing which shows the state which the blade of FIG. 17 contacted the internal peripheral surface.

[First Embodiment]
In FIG. 1, an agitation device 10 according to the first embodiment heats and concentrates a treatment liquid, and includes a heat transfer cylinder 11, a jacket 12, and an agitation unit 14. The heat transfer drum 11 has a vertically long cylindrical shape and is fixed by a fixing member (not shown). In the upper part of the heat transfer cylinder 11, an introduction pipe 15 for introducing the processing liquid into the heat transfer cylinder 11 and an exhaust pipe 16 for discharging steam generated in the heat transfer cylinder 11 are provided. Further, an outlet 17 for taking out the concentrated processing liquid is provided at the lower part of the heat transfer cylinder 11. The inside of the heat transfer cylinder 11 is brought into a state where the pressure is reduced from the atmospheric pressure. A jacket 12 is provided on the outer periphery of the heat transfer drum 11 so as to surround it. A heat medium, for example, steam or hot water having a predetermined temperature is supplied between the jacket 12 and the heat transfer cylinder 11. Thereby, the heat transfer drum 11 is heated.

  The stirring unit 14 includes a motor 21 provided on the upper outer side of the heat transfer drum 11, a main shaft 22 arranged inside the heat transfer drum 11, an arm 23, a blade 26 attached to the main shaft 22 via a connecting portion 24, and the like. It is configured. The main shaft 22 is rotatably arranged at the axial center position of the heat transfer cylinder 11, and the upper end portion is connected to the motor 21 and the lower end portion is supported by the bearing 28. The bearings 28 are supported by stays 28a that are radially arranged. The main shaft 22 is rotated at a predetermined speed by the rotation of the motor 21.

  A plurality of arms 23 are integrally provided on the main shaft 22. In this example, four arms 23 are provided at 90 ° intervals in the circumferential direction of the main shaft 22. A blade 26 is attached to the tip of each arm 23 via a connecting portion 24. As will be described in detail later, each blade 26 rotates around the main shaft 22 with a part of the tip thereof being in contact with the inner peripheral surface 11a of the heat transfer drum 11.

  As shown in FIG. 2, the connecting portion 24 includes a base portion 31 provided at the tip of the arm 23, a pin 32 serving as a swing shaft, and the like. The base 31 has a pair of plate-like support pieces 31a arranged in parallel in the vertical direction. The pins 32 are respectively passed through holes 33 provided in the respective support pieces 31 a and assembled in parallel to the main shaft 22. In the blade 26, a pin 32 is passed through a hole 26a provided in a rear end portion between the pair of support pieces 31a. Thus, the blade 26 is attached to the main shaft 22 through the connecting portion 24 and the arm 23 so as to be swingable around a swing shaft parallel to the main shaft 22. That is, the blade 26 is configured to be swingable about a swing shaft parallel to the main shaft 22, so that the tip of the blade 26 is movable in the radial direction around the main shaft 22.

  The blade 26 is made of, for example, a resin such as Teflon (registered trademark), polyether ether ketone (PEEK), nylon, or the like. The blade 26 is provided with a projecting portion 34 and a clearance forming portion 35 at the tip thereof. The blade 26 has substantially the same length as the inner peripheral surface 11a, more precisely, the thin film forming region on the inner peripheral surface 11a where a thin film is to be formed.

  The protruding portion 34 is a portion where the radius of the rotation trajectory around the main shaft 22 is maximized in the tip portion of the blade 26 and is a substantial tip of the blade 26 that contacts the inner peripheral surface 11a. The clearance forming portion 35 is a portion of the tip end portion of the blade 26 whose radius of rotation around the main shaft 22 is smaller than that of the protruding portion 34, and forms a clearance CL (see FIG. 4) between the inner peripheral surface 11a. . In this example, projecting portions 34 are provided at both ends of the tip of the blade 26, and a clearance forming portion 35 is formed between the pair of projecting portions 34.

  In FIG. 3, when the main shaft 22 rotates, the blade 26 swings around the swing shaft (pin 32) due to the centrifugal force generated by the rotation around the main shaft 22. Due to this swinging, the blade 26 changes to a posture in which the radius of the rotation locus of the protrusion 34 around the rotation center of the main shaft 22 is increased. At this time, the maximum radius L1 of the rotation locus of the protrusion 34 is set to be larger than the maximum distance L2 from the rotation center of the main shaft 22 to the inner peripheral surface 11a. Thereby, as shown by a solid line in FIG. 3, when the main shaft 22 rotates, the blade 26 rotates around the main shaft 22 with the protruding portion 34 in contact with the inner peripheral surface 11 a.

  The maximum radius L1 is the foremost surface of the protrusion 34 when the main shaft 22 is rotated in a state where the swinging of the blade 26 is not restricted by the inner peripheral surface 11a, as indicated by a two-dot chain line in FIG. This is the radius of the rotation trajectory of (the outermost peripheral surface). This maximum radius L1 is the distance from the center of rotation of the main shaft 22 to the most distal surface of the protrusion 34 when the center of rotation of the main shaft 22, the center of oscillation of the blade 26 and the center of gravity of the blade 26 are aligned. Can be sought. Further, the maximum distance L2 can be determined from the assumed magnitude of distortion of the heat transfer cylinder 11 and the deviation of the rotation center of the main shaft 22 from the axial center position of the heat transfer cylinder 11.

  As shown in FIG. 4, the protrusion 34 is always in contact with the inner peripheral surface 11a, so that the clearance forming portion 35 is not in contact with the inner peripheral surface 11a, and between the clearance forming portion 35 and the inner peripheral surface 11a. Form a clearance CL. Even if there is a distortion of the heat transfer cylinder 11 or a shift of the rotation center of the main shaft 22 with respect to the axial center position of the heat transfer cylinder 11, the protruding portion 34 is always in contact with the inner peripheral surface 11a. The size A is maintained almost constant. In this way, since the clearance CL is maintained substantially constant, the blade 26 rotates while forming a thin film of processing liquid having a substantially constant film thickness by the clearance CL.

  The size A of the clearance CL corresponds to the protruding length of the protruding portion 34 from the clearance forming portion 35 of the blade 26, that is, the depth of the clearance forming portion 35. By adjusting the depth of the clearance forming portion 35, the thin film of the treatment liquid formed on the inner peripheral surface 11a can be set to a desired thickness. Thereby, the thin film of the treatment liquid is maintained at an optimum thickness, and an intended evaporation rate, for example, a high evaporation rate is maintained. Note that a thin film of the processing solution may be interposed between the protrusion 34 and the inner peripheral surface 11a. This is because the thin film of the treatment liquid formed between the protruding portion 34 and the inner peripheral surface 11a is substantially constant.

  The size A of the clearance CL is preferably 3 mm at the maximum, and more preferably 1.2 mm at the maximum. If the size A of the clearance CL is 3 mm or less, an appropriate thin film can be more reliably formed and the efficiency of evaporation and heat exchange can be increased. Further, if the size A of the clearance CL is set to 1.2 mm or less, an appropriate thin film can be more reliably formed, and the efficiency of evaporation and heat exchange can be further increased.

  In this case, for example, the protrusion length of the protrusion 34 from the clearance forming portion 35 may be 3 mm or less or 1.2 mm or less. When the distance from the center of rotation of the main shaft 22 to the inner peripheral surface 11a of the heat transfer cylinder 11 is not constant, the blade 26 moves along with the change in the distance to the inner peripheral surface 11a while the blade 26 rotates once around the main shaft 22. The tilt angle changes, and the size A of the clearance CL changes accordingly. However, the size A of the clearance CL does not become larger than the protruding length of the protruding portion 34. Therefore, by setting the protruding length of the protruding portion 34 to 3 mm or less or 1.2 mm or less, the size A of the clearance CL does not exceed the protruding length of 3 mm or 1.2 mm. Further, the maximum value of the range in which the magnitude A of the clearance CL changes may be adjusted to be 3 mm or less or 1.2 mm or less.

  The blade 26 preferably has a contact length, that is, a length in the direction (vertical direction) along the main shaft 22 of the protruding portion 34 as short as possible. Thereby, the probability that the protrusion 34 collides with the local unevenness of the inner peripheral surface 11a or the convex portion of the treatment liquid fixed to the inner peripheral surface 11a by heating can be reduced, and the tip of the blade 26 can be lowered. It is possible to reduce the occurrence of jumping that swings in the direction away from the peripheral surface 11a, and to suppress fluctuations in the film thickness of the processing liquid.

  Further, by giving the blade 26 a degree of freedom other than the swing around the swing axis, the blade 26 is prevented from jumping up as a whole. In this example, a degree of freedom is provided in each of a radial direction around the swing shaft (pin 32), a swing shaft direction, and a direction around an axis perpendicular to a surface formed by the swing shaft and the tip of the blade 26. Yes. Specifically, by making the diameter of the hole 26a (see FIG. 2) provided in the rear end portion of the blade 26 larger than the diameter of the pin 32, the blade 26 is moved in the radial direction around the swing axis. The blade 26 can be moved along the pin 32 by making the distance between the pair of support pieces 31 a larger than the length of the rear end portion of the blade 26 in the vertical direction.

  Further, as described above, the diameter of the hole 26a is made larger than the diameter of the pin 32, and the gap between the rear end portion of the blade 26 and the pair of support pieces 31a is included between the base portion 31 and the blade 26. By securing a predetermined interval, as shown in FIG. 5, the shaft is rotatable about an axis perpendicular to the surface formed by the swing shaft and the tip of the blade 26. In FIG. 5, the axis perpendicular to the plane formed by the swing axis and the tip of the blade 26 is the direction perpendicular to the paper surface, and the blade 26 rotates between the position indicated by the solid line and the position indicated by the two-dot chain line. Move. Even if the blade 26 swings around the swing axis, the blade 26 can rotate around an axis perpendicular to the surface formed by the swing shaft and the tip of the blade 26 at the swing position. In FIG. 5, the distance between the blade 26 and the base 31 is exaggerated in order to explain the rotation of the blade 26.

  By providing the blades 26 with a degree of freedom as described above, even when the blades 26 collide with local irregularities on the inner peripheral surface 11a or the convex portions of the fixed processing liquid, the change in the magnitude A of the clearance CL is changed. I try to make it smaller. That is, when the blade 26 collides with a convex portion or the like, the blade 26 not only swings around the swing shaft but also moves in the radial direction around the swing shaft, moves in the swing shaft direction, and the swing shaft. The blade 26 is prevented from jumping up as a whole by changing the posture while rotating around an axis perpendicular to the surface formed by the blade 26 and the tip of the blade 26.

  In addition, the structure which gives these freedom degrees to the braid | blade 26 is not restricted to the above thing, For example, the diameter of the hole 33 of each support piece 31a which lets the pin 32 provided in each support piece 31a pass is larger than the diameter of the pin 32. The blade 26 may be given a degree of freedom in the radial direction of the pin 32 by increasing the size. In addition, when the blade 26 is prevented from bouncing up overall due to the change in posture as described above, it is also preferable that the protruding portion 34 has a curved surface shape, a spherical shape, or the like.

  The operation of the above configuration will be described. First, the rotation of the motor 21 causes the main shaft 22 to rotate in one direction at a predetermined rotational speed, and for example, steam at a predetermined temperature is supplied into the jacket 12. Each blade 26 rotates around the main shaft 22 by the rotation of the main shaft 22, and each blade 26 swings around the pin 32 by the centrifugal force generated by the rotation. At this time, each blade 26 is in a state in which the protruding portion 34 is in contact with the inner peripheral surface 11a. As a result, a clearance CL is formed between the clearance forming portion 35 and the inner peripheral surface 11a, and each blade 26 rotates around the main shaft 22 in this state.

  In the state where the main shaft 22 is rotated as described above, the processing liquid is supplied into the heat transfer cylinder 11 from the introduction pipe 15. The supplied processing liquid is spread on the inner peripheral surface 11a by the tip of each rotating blade 26 while flowing down the inner peripheral surface 11a, and becomes a thin film. That is, the processing liquid enters the clearance CL formed between the clearance forming portion 35 of the blade 26 and the inner peripheral surface 11a, and is thinned to a thickness corresponding to the size A of the clearance CL.

  The processing liquid in the form of a thin film is heated by being supplied with heat from the steam supplied to the jacket 12 through the heat transfer cylinder 11, and, for example, water in the processing liquid evaporates. As a result, the treatment liquid flowing down in the form of a thin film is concentrated with the moisture gradually decreasing as it flows down. Then, the treatment liquid having a high concentration is sequentially taken out from the outlet 17.

  By the way, the distance from the rotation center of the main shaft 22 to the inner peripheral surface 11a may fluctuate due to the shift of the rotation center of the main shaft 22 from the axial position of the heat transfer drum 11, the distortion of the heat transfer drum 11, or the like. However, in the blade 26, the maximum radius L1 of the rotation locus of the protrusion 34 around the main shaft 22 is larger than the maximum distance L2 from the center of rotation of the main shaft 22 to the inner peripheral surface 11a. Maintain contact. At this time, when the distance from the rotation center of the main shaft 22 to the inner peripheral surface 11a changes, the angle at which the blade 26 tilts changes according to the distance, but the amount of change in the magnitude A of the clearance CL is Since it becomes smaller with respect to the amount of change in the distance to the peripheral surface 11a, the magnitude A of the clearance CL can be regarded as being substantially constant.

  As described above, the size A of the clearance CL becomes substantially constant, and the thin film of the processing liquid spread by the blade 26 on the inner peripheral surface 11a is maintained at an optimum thickness, and for example, a high evaporation rate is always obtained. . In this way, the treatment liquid is efficiently concentrated.

  Further, on the movement trajectory on the inner peripheral surface 11a of the projecting portion 34, irregularities are formed on the inner peripheral surface 11a itself of the heat transfer cylinder 11, or the concentrated processing liquid is fixed to the inner peripheral surface 11a by heating. A convex part may be formed. In such a case, the blade 26 is swingable around the pin 32, and is also perpendicular to the axial direction of the pin 32 and its radial direction, the surface formed by the swing shaft and the tip of the blade 26. Since each has a degree of freedom around the axis, when the protrusion 34 passes through the portion, the blade 26 is only small and changes its posture, and the thin film of the processing liquid is kept at an almost optimum thickness. Of course, since the contact length of the protrusion 34 is shortened, the blade 26 is unlikely to change its posture. Therefore, the processing liquid is spread more efficiently.

  Further, since the blade 26 can swing at least around the pin 32, a convex portion formed on the inner peripheral surface 11a itself of the heat transfer cylinder 11 or a convex portion where the concentrated processing liquid is fixed to the inner peripheral surface 11a. Even if the blade collides with the tip of the blade 26 including the protruding portion 34, the blade 26 is not damaged.

  In the first embodiment, the protrusions are provided at both ends of the blade tip. However, one or more protrusions may be provided at the blade tip, and the position of the protrusion at the blade tip is not limited. For example, as in the example shown in FIG. 6, four protrusions 34 may be provided at the tip of the blade 26 at a predetermined interval. In this case, the blade 26 rotates in a state where the four protrusions 34 are in contact with the inner peripheral surface 11a, and a clearance CL is formed between each clearance forming portion 35 and the inner peripheral surface 11a.

[Second Embodiment]
In the second embodiment, a plurality of blades are arranged side by side at a predetermined interval in the axial direction of the main shaft. Except for the details described below, the second embodiment is the same as the first embodiment, and substantially the same members are denoted by the same reference numerals and detailed description thereof is omitted.

  In FIG. 7, three blades 46 are arranged at predetermined intervals in the axial direction (vertical direction) of the main shaft 22 at the tip of each arm 23 of the stirring device 40. Each blade 46 is connected to the arm 23 via the connecting portion 24. The vertical length of the blade 46 is about 1/3 of the vertical direction of the thin film formation region, and the processing liquid on the thin film formation region is spread by three blades 46 arranged in the vertical direction. .

  As shown in FIG. 8, the connecting portion 24 is provided with a pair of support pieces 31a for each blade 46, and each blade 46 is swingably attached to a corresponding pair of support pieces 31a by pins 32A. It has been. Thus, the blades 46 can swing independently of each other. Similarly to the blade 26 of the first embodiment, each blade 46 is also perpendicular to the radial direction centering on the swing shaft (pin 32A), the swing shaft direction, and the plane formed by the swing shaft and the tip of the blade 46. Each axis has a degree of freedom. In addition, each blade 46 has a protrusion 34 formed at each end of the tip, and a clearance forming portion 35 is provided at the tip between these protrusions 34.

  According to this example, each blade 46 forms a clearance CL between the clearance forming portion 35 and the inner peripheral surface 11a when the protruding portion 34 contacts the inner peripheral surface 11a. As in the first embodiment, since the size of the clearance CL is kept substantially constant by the protrusion 34 coming into contact with the inner peripheral surface 11a, the thin film of the processing liquid spread by each blade 46 is formed. The optimum thickness is maintained.

  Further, even when any one of the three blades 46 arranged in the vertical direction collides with the convex portion or the like to which the treatment liquid is fixed, the posture changes including the jumping up. Only the blades 46 collided with each other, and the postures of the other blades 46 do not change. For this reason, the range in which the film thickness changes is reduced, and the thin film can be maintained at an optimum thickness over a wide range.

[Third Embodiment]
In the third embodiment, the tip of the blade is urged in a direction in contact with the inner peripheral surface. Except for the details described below, the second embodiment is the same as the first embodiment, and substantially the same members are denoted by the same reference numerals and detailed description thereof is omitted.

  As shown in FIG. 9, a blade 52 is attached to the arm 23 via a connecting portion 51. The connecting portion 51 includes a fixed plate 53 fixed to the arm 23, and a movable plate 54 that is swingable about an axis parallel to the main shaft 22 to the fixed plate 53. In this example, the fixed plate 53 and the movable plate 54 are connected by a hinge 55. A blade 52 is fixed to the movable plate 54.

  The blade 52 is provided with protrusions 34 at both ends of the tip, and a clearance forming part 35 is provided between the protrusions 34. As described above, the blade 52, together with the movable plate 54, is swingable about the swing axis parallel to the main shaft 22 by the hinge 55. A spring hinge is used as the hinge 55, and the torsion spring 55 a of the hinge 55 urges the blade 52 in the same direction as the rotation direction of the main shaft 22. In FIG. 9, the rotation direction of the main shaft 22 is clockwise, and the torsion spring 55 a biases the blade 52 in the clockwise direction around the axis of the hinge 55. In this example, the torsion spring 55a is an elastic member.

  As shown in FIG. 10, the blade 52 is tilted against the urging force of the torsion spring 55a and the heat transfer cylinder 11 is brought into contact with the inner peripheral surface 11a by the urging force of the torsion spring 55a. Arranged inside. Thereby, the blade 52 rotates around the main shaft 22 in a state where the protruding portion 34 is pressed against the inner peripheral surface 11a by the bias of the torsion spring 55a. The clearance CL formed between the clearance forming portion 35 of the blade 52 and the inner peripheral surface 11a is kept substantially constant in the same manner as in the first embodiment. The liquid film is kept at the optimum thickness.

  In the above example, a torsion spring is used as an elastic member that biases the blade 52, but the elastic member is not limited to this. For example, in the example of FIG. 11, the leaf spring 60 is used as the elastic member. A blade 52 is attached to the arm 23 via a connecting portion 61. In addition to the pair of leaf springs 60, the connecting portion 61 includes a fixed plate 63 fixed to the arm 23 and a movable plate 64 to which the blade 52 is fixed. The fixed plate 63 and the movable plate 64 are pivotally attached to the shaft 65, so that the blade 52 and the movable plate 64 can swing around a swing shaft parallel to the main shaft 22. Each leaf spring 60 has one end fixed to the fixed plate 63 and the other end fixed to the movable plate 64. As shown in FIG. 12, the blade 52 is tilted integrally with the movable plate 64 against the urging of the leaf spring 60, and the deflected portion of the projecting portion 34 is deformed by the urging of the leaf spring 60. It is arranged in the heat transfer cylinder 11 in a state of being pressed against the heat transfer cylinder 11. In this state, the blade 52 rotates around the main shaft 22.

  Moreover, as shown in FIG. 13, you may connect the fixed plate 73 and the movable plate 74 using the compression spring 70 as an elastic member. In this configuration, the projecting portion 34 of the blade 52 is movable in the radial direction about the main shaft 22 by the expansion and contraction of the compression spring 70. Further, the length from the rotation center of the main shaft 22 to the inner peripheral surface 11a is made longer than the maximum distance L2 from the rotation center of the main shaft 22 when the compression spring 70 has a natural length. By doing so, the maximum radius of the rotation trajectory of the protrusion 34 around the main shaft 22 is at least larger than the maximum distance L2 from the rotation center of the main shaft 22 to the inner peripheral surface 11a.

  In this example, as indicated by a solid line in FIG. 14, the blade 52 is disposed in the heat transfer drum 11 in a state where the compression spring 70 is compressed in the radial direction around the main shaft 22. Accordingly, the blade 52 is rotated around the main shaft 22 in a state where the projecting portion 34 presses the inner peripheral surface 11a in the vertical direction by the bias of the compressed compression spring 70. As indicated by a two-dot chain line in FIG. 14, the blade 52 is tilted in the direction opposite to the rotation direction around the main shaft 22 due to the frictional force between the inner peripheral surface 11a and the treatment liquid on the inner peripheral surface 11a. It may be a posture.

  In each of the above embodiments, a protrusion and a clearance forming portion are provided at the tip of the blade so that a clearance is formed between the blade and the inner peripheral surface of the heat transfer cylinder. However, as in the example shown in FIG. In addition, the tip of the blade 80 may be flat (straight). In this case, the clearance formed between the blade 80 and the inner peripheral surface 11a is “0”. In addition, as shown in FIG. 16, when a thin film is formed in a thin film forming region of the inner peripheral surface 11a using a plurality of small-sized blades 81, the tip of the blade 81 is similarly flattened to form the inner peripheral surface. It is good also considering the clearance between 11a as "0". In this case, the maximum radius L1 of all the rotation trajectories of the tips of the blades 80 and 81 around the main shaft 22 is larger than the maximum distance L2 from the rotation center of the main shaft 22 to the inner peripheral surface 11a. 15 and 16 is the same as the example shown in FIGS. 4 and 8 except that the tips of the blades 80 and 81 are flat, and the same components are the same as those shown in FIGS. The code | symbol is attached | subjected. Of course, a blade having a flat tip can also be used in the configurations of the examples shown in FIGS. 9, 11, and 13.

  Another example using a blade having a flat tip is shown in FIGS. The blade 90 shown in FIGS. 17 and 18 is configured such that the blade 90 can swing by its own elasticity. The blade 90 is formed in a plate shape with, for example, silicon rubber so as to be elastically deformable. The blade 90 has a flat tip, and the entire tip contacts the inner peripheral surface 11a.

  The blade 90 is fixed to a fixing plate 91 whose rear end is provided integrally with the arm 23. The blade 90 is assembled in a state where the tip of the blade 90 is pressed against the inner peripheral surface 11a and the blade 90 itself is elastically deformed. In this example, the tip portion of the blade 90 is elastically deformed so as to be bent. The blade 90 is attached to the fixing plate 91 in the radial direction about the main shaft 22 such that the tip of the blade 90 maintains contact with the inner peripheral surface 11a during one rotation around the main shaft 22. That is, the amount of elastic deformation is adjusted. As a result, when the diameter in the radial direction around the main shaft 22 changes, the blade 90 increases or decreases its own elastic deformation amount and maintains the state where the tip is pressed against the inner peripheral surface 11a. In this manner, the blade 90 swings the tip side portion including the tip by its own elasticity. Therefore, in this blade 90, the portion on the rear side of the tip end portion functions as a connecting portion that connects the main shaft 22 with the tip end portion being swingable. The blade 90 has a flat tip, but a blade provided with a protrusion and a clearance forming portion at the tip may be swingable by its own elasticity.

  As described above, even when the tips of the blades 80, 81, 90 are flat, since the blades 80, 81, 90 can swing, the tips of the blades 80, 81, 90 swing away from the inner peripheral surface 11a. The processing liquid enters between the inner peripheral surface 11a and a thin film of the processing liquid is formed on the inner peripheral surface 11a. Since the thickness of the thin film of the processing liquid is determined according to the viscosity of the processing liquid, the centrifugal force acting on the blades 80 and 81, the elasticity of the blade 90, and the deformation amount, the thickness can be made almost constant.

  In addition, when the blade is movable only in the radial direction around the main axis, when the convex part formed on the inner peripheral surface hits the tip of the blade, the blade moves so that the blade moves in the central direction. The tip is preferably a slope or a curved surface.

  Moreover, although each said embodiment demonstrated the case where a process liquid was heated and concentrated, this invention can be utilized also when heating is further advanced and it dries and pulverizes. Furthermore, the present invention can also be used to cool the processing liquid by supplying a refrigerant to the heat transfer cylinder.

  Next, Examples 1 to 5 of the present invention will be described. In Examples 1 to 5, the treatment liquid was concentrated using a stirrer, and the evaporation rate at the time of concentration was measured.

  The stirrer used in Examples 1 and 2 has the same configuration as the stirrer 40 shown in FIG. 7, but has a configuration in which four blades 46 are arranged in the vertical direction for each arm 23. . As in the configuration shown in FIG. 7 and the like, the connecting portion 24 has a configuration in which each blade 46 is swingably held by a pin 32A, and the protruding portion 34 of the blade 46 is brought into contact with the inner peripheral surface 11a by centrifugal force. there were. Note that there are four arms 23.

  The length of the blade 46 in the vertical direction was 9.8 cm. Further, by adjusting the protruding length of the protruding portion 34, the size A of the clearance CL is set to 1.2 mm in the first embodiment and 0.6 mm in the second embodiment. The inner diameter of the heat transfer cylinder 11 was 550 mm. The rotation speed of the main shaft 22 was 200 rpm (rotations / minute), the pressure inside the heat transfer cylinder 11 was 0.08 MPa lower than the atmospheric pressure, and the steam temperature supplied to the jacket 12 was 150 ° C.

  In the measurement, a liquid (a solid content of about 5.1%, a fat content of about 8%, and a protein content of about 7%), which is a mixture of milk ingredients and sugar, is used as a processing solution, and the evaporation rate until the solid content reaches about 70%. Was measured.

  In Example 3, instead of the blade 46 of Examples 1 and 2, a blade 81 having a flat tip as in the example shown in FIG. 16 was used, and the size of the clearance CL was set to 0 mm. In the third embodiment, as in the first and second embodiments, four blades 81 are arranged in the vertical direction for each arm 23, and the tip of the blade 81 is formed on the inner peripheral surface by centrifugal force. It was set as the structure made to contact 11a. Other conditions in Example 3 were the same as those in Examples 1 and 2.

  In Example 4, the configuration of the blade 52 and the connecting portion 51 shown in FIG. 9 was used. That is, the projecting portion 34 of the blade 52 is brought into contact with the inner peripheral surface 11a by the biasing force of the torsion spring 55a. In the fourth embodiment, one blade 52 is provided for each arm 23. Further, the protrusion A of the protrusion 34 was adjusted so that the size A of the clearance CL was 0.8 mm. The other conditions in Example 4 were the same as those in Examples 1 and 2.

  In Example 5, the blade 90 shown in FIGS. 18 and 19 was used. That is, the blade 90 is swung by the elasticity of the blade 90 itself. In the fifth embodiment, one blade 90 is arranged for each arm 23. The other conditions were the same as in Example 1.

  The measurement results of Examples 1 to 5 are shown in Table 1. The “force to contact” in Table 1 is the force used to bring the blade into contact with the inner peripheral surface 11a. The evaporation rate is an evaporation rate per heat transfer area.

  In each of Examples 1 to 5, a high evaporation rate is obtained, the blade is provided so as to be swingable, and a part or all of the tip thereof is in contact with the inner peripheral surface 11a. It was found that the film thickness can be reduced. Further, it has been found that using a configuration in which the blade is brought into contact with the inner peripheral surface 11a using centrifugal force provides a higher evaporation rate than a configuration using a torsion spring or the elastic force of the blade.

DESCRIPTION OF SYMBOLS 10, 40 Stirrer 11 Heat transfer cylinder 11a Inner peripheral surface 22 Main shaft 24 Connection part 26, 46, 52, 80, 81, 90 Blade 34 Projection part 35 Clearance formation part 55a Torsion spring 60 Leaf spring 70 Compression spring

Claims (8)

A cylindrical heat transfer cylinder,
A main shaft disposed in the heat transfer cylinder;
A blade attached to the main shaft, moving along the inner peripheral surface of the heat transfer cylinder by rotating with the main shaft, and forming a thin film of treatment liquid on the inner peripheral surface;
A connecting portion for connecting the blade and the main shaft by allowing the tip of the blade to move in a radial direction around the main shaft;
The stirring device, wherein a maximum radius of a rotation trajectory of a part or all of the tip of the blade around the main shaft is larger than a maximum distance from a rotation center of the main shaft to the inner peripheral surface.   The blade has a protrusion having a maximum radius of the rotation locus around the main axis, and a radius of the rotation locus around the main axis smaller than the protrusion, and the protrusion is in contact with the inner peripheral surface. The stirring device according to claim 1, wherein a clearance forming portion that forms a clearance with the inner peripheral surface is formed at each end.   3. The blade according to claim 2, wherein a plurality of the protrusions are provided at predetermined intervals in the direction of the main shaft, and the clearance forming part is formed between the protrusions and the protrusions. A stirrer described in 1.   The connecting portion has a swing shaft parallel to the main shaft, the blade is swingably attached to the swing shaft, and swings around the swing shaft so as to have a diameter centered on the main shaft. The stirring device according to any one of claims 1 to 3, wherein the stirring device moves in a direction.   The stirring device according to claim 4, wherein the connecting portion holds the blade movably in a radial direction and an axial direction around the swing shaft.   The stirring device according to claim 4 or 5, wherein the blade swings around the swing shaft by a centrifugal force generated by the rotation of the main shaft, and the tip of the blade contacts the inner peripheral surface.   The agitation according to any one of claims 1 to 6, further comprising a plurality of the blades each connected to the main shaft by the connecting portion and arranged at a predetermined interval in an axial direction of the main shaft. apparatus.   The agitation according to any one of claims 1 to 5, wherein the connecting portion includes an elastic member that urges the blade in a direction in which a tip of the blade is brought into contact with the inner peripheral surface. apparatus.

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