Stirring device

Abstract

Even if the material being stirred adheres to the top of the stirring tank, the adhered material should be removed promptly. [Solution] The stirring device 10 comprises a stirring tank 11 having a bottom surface 16 and a pair of side surfaces 17, 18 for containing the material, a stirring blade 35 provided inside the stirring tank 11 for stirring the material, and a scraper 43 that reciprocates along the side surface 17 while the stirring blade 35 moves away from the side surface 17, scraping off any material adhering to the side surface 17.

Description

Technical Field

[0001] The present invention relates to an apparatus for stirring granules and powders.

Background Art

[0002] As a stirring apparatus that introduces granules obtained by crushing grains and water into a stirring tank having a longitudinal direction and a width direction and stirs the mixture, for example, the stirring apparatus described in Japanese Laid-Open Patent Publication No. 2005-238037 (Patent Document 1) is conventionally known. In the stirring apparatus described in Patent Document 1, new granules are introduced together with water at one end in the longitudinal direction of the stirring tank. The granules to which water has been added advance through the conveying section while being vibrated, stirred and conveyed, and the completed mixture is taken out from the other end in the longitudinal direction of the stirring tank. The stirring apparatus continuously performs the above stirring operation.

[0003] During operation of the stirring apparatus, granules adhere to the main shaft which is the rotation center of the stirring blades. The stirring apparatus described in Patent Document 1 has an air jet nozzle that blows air onto the main shaft to remove the granules adhering to the main shaft.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problem to be Solved by the Invention

[0005] However, the present inventor has found that the conventional stirring apparatus as described above still has points to be further improved. That is, due to the continuous operation of the stirring operation, high-moisture granules to which water has been added adhere to the upper portions of both side surfaces in the width direction of the stirring tank, and it is difficult to remove the granules adhering to the side surfaces of the stirring tank by the vibration applied to the stirring tank by the vibration generator, and the water-rich granules remain for a long time without being stirred. Since the water-containing granules are food materials, long-term retention is not preferable in terms of quality control.

[0006] In view of the above circumstances, the present invention aims to provide a technology that allows for the rapid removal of material that adheres to the upper part of the stirring tank even if it adheres to the tank during stirring. [Means for solving the problem]

[0007] For this purpose, the stirring device according to the present invention comprises a stirring tank having a bottom surface and a pair of sides for containing material, a stirring member provided in the stirring tank for stirring the material, and a scraper that reciprocates along the sides of the stirring tank while the stirring member moves away from the sides of the stirring tank to scrape off material adhering to the sides.

[0008] According to this invention, material adhering to the side of the stirring tank is thoroughly scraped off by the scraper. Therefore, even if the stirring device is operated continuously for a long time, the material will not remain on the upper side for an extended period. Consequently, if the material is food, deterioration of the adhering material will not occur, and the inside of the stirring tank will be kept hygienic. The drive mechanism for the stirring member and the scraper are not particularly limited. The stirring member and the scraper may be driven by separate drive sources, or they may be driven by a common drive source.

[0009] The shape of the stirring member is not particularly limited. The stirring member may be a blade or spatula extending along the bottom surface of the stirring tank, or a paddle or blade extending perpendicular to the bottom surface of the stirring tank. The operation of the stirring member is not particularly limited. The stirring member may oscillate, rotate, reciprocate, or rotate. In one aspect of the present invention, the stirring member reciprocates from one side of the stirring tank along the bottom surface to the other side of the stirring tank, and the scraper includes a first scraper that reciprocates along one side of the stirring tank and a second scraper that reciprocates along the other side of the stirring tank, with the first and second scrapers operating alternately. In this aspect, the operation of the stirring member, the operation of the first scraper, and the operation of the second scraper are coordinated, so that both sides of the stirring tank are kept hygienic during continuous operation of the stirring device. The direction of operation of the first and second scrapers is not particularly limited, such as forward and backward, up and down, etc. For example, while the first scraper moves downwards, the second scraper moves upwards.

[0010] The operation of the stirring member is not limited. In a preferred aspect of the present invention, the stirring member can be selected to either a first mode, which is a mode that performs an operation pattern suitable mainly for stirring materials, or a second mode, which is a mode other than stirring materials, such as waiting away from the materials for cleaning, etc., and the scraper operates in a relatively narrow range in the first mode and in a relatively wide range in the second mode. In this aspect, cleaning can be performed automatically not only during the material stirring operation by the stirring device, but also during the cleaning stage after the stirring operation is completed. Preferably, in the second mode, the stirring member is also operated so that the surface of the stirring member can be washed with water. The operation of the stirring member is not particularly limited, but for example, it may operate at a constant period synchronized with the operation of the scraper so as not to interfere with the scraper. Alternatively, in the second mode, the stirring member may remain stationary in a position adjacent to the bottom surface of the stirring tank and not operate. In another aspect, the reciprocating range of the scraper may be the same in both the first mode and the second mode.

[0011] The shape of the stirring tank is not particularly limited, but in one aspect of the present invention, it is further provided with a main shaft positioned between a pair of sides and extending parallel to these sides, and the stirring member is connected to the main shaft. In this aspect, the space between the pair of sides is the width direction, the stirring tank is lengthened in a direction perpendicular to the width direction, and by flowing the material along the longitudinal direction of such an elongated stirring tank, continuous stirring operation can be suitably performed.

[0012] The structure for driving the scraper is not particularly limited, but in one aspect of the present invention, a collar is further provided through which the main shaft passes, and the scraper is connected to the collar. In this aspect, the scraper can be made to reciprocate so as to swing around the main shaft. [Effects of the Invention]

[0013] Thus, according to the present invention, even if the material being stirred adheres to the upper part of the stirring tank in a stirring device during stirring operations, the adhered material can be sufficiently removed. As a result, even when the stirring device is operated continuously, no changes in the adhered material occur over time, and the stirring tank is kept hygienic. [Brief explanation of the drawing]

[0014] [Figure 1] This is a perspective view showing a stirring device which is one embodiment of the present invention. [Figure 2] This is an exploded perspective view showing the same embodiment. [Figure 3] This is a cross-sectional view of the same embodiment, where (a) to (c) represent the operation of the stirring blade. [Figure 4] This is a cross-sectional view of the same embodiment, where (a) to (c) represent the operation of the scraper. [Modes for carrying out the invention]

[0015] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Figure 1 is a perspective view showing an agitator according to one embodiment of the present invention. Figure 2 is an exploded perspective view showing the same embodiment. The agitator 10 comprises an agitator 11, a frame 12, a vibration source 21, a main shaft 31, an agitator blade 35 (agitator member, Figure 2), and a drive motor 33. The agitator 11 has one end 13 and the other end 14, and is elongated and extends substantially horizontally. The agitator 11 is supported from below by a frame 12 having four legs 15, and is sloped so that one end 13 is slightly higher than the other end 14. The one end 13 and the other end 14 are each stopped by end walls to prevent the material in the tank from spilling out of the tank from the one end 13 and the other end 14.

[0016] Figure 3 is a cross-sectional view showing a section of the stirring tank 11 cut by a plane perpendicular to the longitudinal direction, representing the left and right sides in the width direction of the stirring tank. The stirring tank 11 has a bottom surface 16 and a pair of left and right sides 17 and 18 that face each other in the width direction of the stirring tank 11. In Figure 3 and other drawings, the left side is represented by arrow L, the right side by arrow R, the top by arrow U, and the bottom by arrow D. The longitudinal direction of the stirring tank 11 is perpendicular to the plane of the paper in Figure 3. The bottom surface 16 is a curved surface with a circular arc in cross-section, where the center in the width direction is the lowest and both sides in the width direction are higher, and is specifically a cylindrical surface. The sides 17 and 18 are planes rising from both edges of the bottom surface 16 in the width direction. Alternatively, the sides 17 and 18 are concave curved surfaces with a gentler curvature than the circular arc of the bottom surface 16. The cross-sections of the continuous side surface 17, bottom surface 16, and side surface 18, that is, the cross-sectional shape of the stirring tank 11 in this embodiment, is U-shaped when viewed in the longitudinal direction of the stirring tank 11. A vibration source 21 (Figure 1) is attached to the outside of the plate material of the stirring tank 11 that constitutes the bottom surface 16. The vibration source 21 is, for example, an electric vibration motor that vibrates the stirring tank 11.

[0017] A main shaft 31 is positioned between a pair of sides 17 and 18 of the stirring tank 11. The main shaft 31 is installed inside the stirring tank 11 and extends from one end 13 to the other end 14. In this embodiment, the main shaft 31 is positioned in the center of the pair of sides 17 and 18 and extends parallel to these sides 17 and 18. Multiple stirring arms 34 are attached to the main shaft 31 at axial intervals. The stirring arms 34 are perpendicular to the main shaft 31 and extend outwards from the main shaft 31. The multiple stirring arms 34 are also arranged in parallel to each other. Stirring blades 35 are attached to the tips of the stirring arms 34. In this embodiment, the stirring blades 35 are an embodiment of a stirring member. The stirring blades 35 are elongated spatulas that extend parallel to the main shaft 31 from one end to the other of the stirring tank 11. The stirring blades 35 are made of stainless steel plate material and are connected to the main shaft via the stirring arms 34. The main shaft 31 is rotated by a drive motor 33, which will be described later. The stirring arm 34 swings around the main shaft 31. The stirring blade 35 moves along the bottom surface 16 in the width direction of the stirring tank 11. The stirring arm 34, which is a stirring member for stirring the material, is a rod member that extends straight at approximately right angles to the bottom surface 16. However, in modified forms not shown, the stirring arm 34 may be paddle-shaped or blade-shaped, extending at approximately right angles to the bottom surface 16, and in this way the stirring arm 34 can stir the material in the tank as a stirring paddle or stirring blade.

[0018] The top of the stirring tank 11 is open, but it is of course possible to cover the top with a cover member (not shown) as appropriate. New material is introduced into one end 13 of the stirring tank 11 from outside the tank. The material is food ingredients, specifically, for example, granules made from crushed polished raw rice or granules made from crushed other grains. The material may have water added to it beforehand, or it may consist only of grains without surface water.

[0019] The stirring device 10 is provided at the upper part of the stirring tank 11, and has a water supply facility (not shown) that sprays water into the tank. Materials are added with water in the tank and stirred by the stirring blades 35. In addition, the water-containing material slowly moves from one end 13 to the other end 14 during the stirring process due to the vibration from the vibration source 21 and the gentle downward gradient from the one end 13 to the other end 14. The sufficiently stirred material is taken out of the tank through a discharge hole formed in the end wall at the other end 14.

[0020] The operation of the stirring blade 35 will be described.

[0021] Referring to Figure 3, the end of the main shaft 31 extending through the end wall at one end 13 is connected to the output shaft 37 of the drive motor 33 via the crank mechanism 36. The crank mechanism 36 includes a plurality of members 36b to 36d, converts the rotational motion of the output shaft 37 in the positive direction (black arrow) into the bidirectional forward and reverse rotational motion of the main shaft 31, and causes the stirring blade 35 to reciprocate in the width direction of the stirring tank 11.

[0022] Figure 3(a) shows a state where the stirring blade 35 has moved to the rightmost side in the width direction, Figure 3(b) shows a state where the stirring blade 35 has moved to the center in the width direction, and Figure 3(c) shows a state where the stirring blade 35 has moved to the leftmost side in the width direction. Driven by the drive motor 33 which is the first drive source, the stirring blade 35 repeats the reciprocating motion of (a), (b), (c), (b), (a)... in Figure 3 to stir the material in the stirring tank 11.

[0023] When the stirring blade 35 moves from Figure 3(b) to Figure 3(c) and rises along the side surface 17, the material in the tank is also lifted, and the material adheres to the upper part of the side surface 17. The same applies to the side surface 18.

[0024] The stirring device 10 of this embodiment further includes a scraper 43 (hereinafter also referred to as the left scraper 43) for scraping off material adhering to the left side surface 17, and a scraper 44 (hereinafter also referred to as the right scraper 44) for scraping off material adhering to the right side surface 18. The scrapers 43 and 44 are arranged symmetrically on the left and right sides within the stirring tank 11. To avoid repetition in the explanation, the following will mainly describe the scraper 43. The scraper 43 includes a metal fitting that extends straight from one end 13 to the other end 14 within the stirring tank 11, parallel to the main shaft 31, and a rubber strip fixed to the metal fitting and in contact with the bottom surface 16 or side surface 17 of the stirring tank 11.

[0025] Referring to the exploded perspective view in Figure 2, the scraper 43 is fixed at one longitudinal end, a central section, and the other end to the free ends of three support arms 45. The base end of each support arm 45 is connected to a cylindrical member, a collar 47. A common main shaft 31 passes through the central openings of each of the multiple collars 47. The other scraper 44 has a similar configuration, and the support arms 46 and collars 48 of the scraper 44 are positioned offset in the axial direction relative to the support arms 45 and collars 47.

[0026] Each support arm 45 includes two flat strips 45b, 45b arranged opposite each other. This ensures bending rigidity for each support arm 45. One of the three collars 47 is connected to one end of the rod 49. The rod 49 protrudes upward from the stirring tank 11 at a predetermined angle with respect to the support arm 45, with respect to the collar 47. In this embodiment, when viewed in the direction of extension of the main shaft 31, the support arm 45 and the rod 49 form a single V-shaped member.

[0027] A long hole 49h is formed in the rod 49. A linear motion member 53 (Figure 4) of the actuator 51 shown in Figure 1 passes through the long hole 49h, and the linear motion member 53 is movable within the long hole 49h along the rod 49. The actuator 51 is positioned on the upper side of the stirring tank 11 in a position that extends in the width direction of the stirring tank 11. Similarly, the scraper 44 is also connected to a linear motion member of another actuator 52.

[0028] Next, we will explain the operation of scrapers 43 and 44.

[0029] Referring to the cross-sectional view of the stirring device 10 shown in Figure 4, (a) represents the highest upper position of the scraper 43 along the side surface 17, (b) represents the middle position of the scraper 43 along the side surface 17, and (c) represents the lowest lower position of the scraper 43 along the bottom surface 16. The upward and downward movement of the scraper 43 is realized by the mechanical motion of a linear motion member 53 that reciprocates along the actuator 51, which is the second drive source, and the elongated hole 49h. To explain using the actuator 51 as an example, the amount of drive (point of force) in the width direction (LR direction) of the linear motion member 53 is converted into an amount of drive (point of application) that drives the scraper 43 in the vertical direction (UD direction), with the collar 47 as the fulcrum. A control unit (not shown) that controls the actuators 51 and 52 controls the amount of drive of the actuator 51 in stages (multi-stage), thereby enabling stepwise control of the amount of drive of the scraper 43. In other words, by changing the drive amount of actuators 51 and 52, the vertical operating range of scrapers 43 and 44 can be changed and controlled in stages.

[0030] As in this embodiment, by employing table-type electric actuators for actuators 51 and 52, the overall height of the stirring device 10 can be reduced (made more compact) compared to using other actuators such as air cylinders.

[0031] Figure 4(a) shows the movable range M of the stirring blades centered on the main shaft 31. The movable range M of the stirring blades occupies the central region in the width direction of the stirring tank 11 and spans the lower part of the side surface 17, the bottom surface 16, and the lower part of the side surface 18. In this embodiment, the movable range M of the blades is a range of 70° to the left and 70° to the right from the center in the width direction of the bottom surface 16, totaling 140°. The stirring blades 35 operate to reciprocate in a cycle of 8 seconds.

[0032] On both the left and right edges of the movable range M of the stirring blade, there are continuous material adhesion regions Fl, where the material lifted by the stirring blade 35 remains attached to the side surface 17, and material adhesion regions Fm, where the material lifted by the stirring blade 35 remains attached to the side surface 18.

[0033] The scraper 43 normally waits in the upper position shown in Figure 4(a). The upper position is above the material adhesion range Fl. Therefore, even when the stirring mode (first mode) in which the stirring blade 35 stirs the material in the tank is selected and the stirring blade 35 reciprocates across the entire range of motion M of the stirring blade, the scraper 43 does not interfere with the stirring blade 35. Furthermore, it does not come into contact with the material that is lifted up to the material adhesion range Fl by the stirring blade 35, nor with the material that remains attached to the material adhesion range Fl.

[0034] During this stirring mode, as shown in Figures 4(a) to 4(c), when the stirring blade 35 is positioned on the right side of the stirring blade's movable range M and separates from the left scraper 43, the scraper 43 temporarily descends from the upper position (a) to the middle position (b), and then immediately returns to the upper position (a). The scraper operating range Sj of the scraper 43 in stirring mode is shown in Figure 4(b). The scraper operating range Sj overlaps with the material adhesion range Fl and extends above the material adhesion range Fl, but does not overlap with the stirring blade's movable range M. The scraping action of the scraper 43 returning to the upper position (a) via the middle position (b) only needs to be synchronized with the reciprocating motion of the stirring blade 35, and the frequency of the scraping action is not limited.

[0035] As the scraper 43 descends, the material adhering to the material adhesion area Fl on the left side in the width direction is scraped off toward the bottom surface 16. According to this embodiment, the left side surface 17 in the width direction is regularly cleaned by the scraper 43, so that moisture-containing material does not remain in the material adhesion area Fl for a long time, making it hygienic. Similarly, the right side surface 18 in the width direction is also regularly cleaned by the scraper 44, so that moisture-containing material does not remain in the material adhesion area Fm for a long time, making it hygienic.

[0036] As described above, the reciprocating motion of the stirring blade 35 and the scraping action of the scrapers 43 and 44 are powered by separate power sources (drive motor 33, actuators 51 and 52). The operation of the stirring blade 35 and the operation of the scrapers 43 and 44 are performed separately. To synchronize these separate operations, a position sensor (not shown) is provided at one end 13 to detect the rotational position of the crank mechanism 36 (angle of the main shaft 31 and stirring blade 35). This position sensor transmits the detected rotational position to a control unit (not shown). The control unit, which controls the drive motor 33 and actuators 51 and 52, operates the actuators 51 and 52 so as not to interfere with the stirring blade 35. The configuration of the position sensor is not particularly limited.

[0037] Next, we will describe the scraping action in which the scraper 43 temporarily descends from the upper position in Figure 4(a) to the lower position in (c), and then immediately returns to the upper position in (a).

[0038] If the above-mentioned stirring mode is not selected and the cleaning mode (second mode) is selected, cleaning of the side surface 17 is performed by the scraper 43 using the operation shown in Figures 4(a) to (c). The scraper operating range Sn of the scraper 43 in cleaning mode is shown in Figure 4(c). The scraper operating range Sn overlaps with the material adhesion range Fl, extends further below the material adhesion range Fl, and overlaps with the stirring blade movable range M (Sj <Sn)。

[0039] In this cleaning mode, water may be sprayed onto the side surface 17 from above the stirring tank 11, for example, from a water supply facility (not shown). The side surface 17 is cleaned by the combined action of the scraper 43 and the water. The side surface 18, which is symmetrical to the side surface 17, is also cleaned with the scraper 44.

[0040] Material adheres to both sides of the stirring blade 35 due to repeated reciprocating motion in the stirring mode (first mode). In the cleaning mode (second mode) of this embodiment, the motor 33 may be rotated to operate the stirring blade 35. This allows the water described above to evenly reach both sides of the stirring blade 35, thus cleaning the stirring blade 35. Since the stirring blade 35 operates in synchronization with the scraper 43, it naturally does not interfere with the scraper 43. Alternatively, the motor 33 may be rotated intermittently to operate the stirring blade 35 intermittently. Or, the stirring blade 35 may be retracted from the scraper operating range Sn, for example, the stirring blade 35 may be stopped in the center of the stirring blade movable range M (the central part in the width direction of the bottom surface).

[0041] Although embodiments of the present invention have been described above with reference to the drawings, the present invention is not limited to the illustrated embodiments. Various modifications and variations can be made to the illustrated embodiments within the same or equivalent scope as the present invention. As a variation of this embodiment, the operation of the scraper 43 and the reciprocating motion of the stirring blade 35 do not need to be synchronized during stirring mode. Since the material adhesion range Fl and the stirring blade movable range M do not overlap, the scraper 43 and the stirring blade 35 do not interfere with each other. [Industrial applicability]

[0042] This invention can be advantageously utilized in food processing. [Explanation of symbols]

[0043] 10 Agitator, 11 Agitator, 13 One end of the agitator in the longitudinal direction, 14 The other end in the longitudinal direction of the stirring tank, 16 the bottom surface, 17, 18 the side surfaces, 31 Main shaft, 33 Drive motor, 34 Stirring arm, 35 Stirring blade (stirring component), 43, 44, scraper, 47 colors, 51, 52 actuators.

Claims

1. A stirring tank having a bottom and a pair of sides, for containing the material, A stirring member provided in the stirring tank for stirring the material, A stirring device comprising a scraper that reciprocates along the side surface while the stirring member moves away from the side surface, scraping off the material adhering to the side surface.

2. The stirring member reciprocates from one side along the bottom surface to the other side, The scraper includes a first scraper that reciprocates along one of the sides and a second scraper that reciprocates along the other side. The stirring device according to claim 1, wherein the first scraper and the second scraper operate alternately.

3. The stirring member can be selected to operate in either a first mode or a second mode. The stirring device according to claim 2, wherein the scraper operates over a relatively narrow range in the first mode and over a relatively wide range in the second mode.

4. The device further comprises a main shaft positioned between the pair of sides and extending parallel to these sides, The stirring member is connected to the main shaft, as described in any one of claims 1 to 3.

5. The aforementioned main shaft is further equipped with a collar, The stirring device according to claim 4, wherein the scraper is connected to the collar.

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