Vibration feeder

Abstract

To provide a vibration feeder capable of stably and efficiently feeding powder stuck to an article to be conveyed from the article.SOLUTION: A second bowl part 63 is disposed inside a first bowl part 62 and has a second bottom surface BS2 provided with a plurality of through-holes 90 having sizes to pass powder while blocking passage of an article 9 to be conveyed. An input part 701 inputs the article 9 on the center region RC of the second bottom surface BS2. A vibrator vibrates the second bowl part 63. At least one guide 81 is for guiding the article 9 so as to revolve the article 9 in a revolving direction which is one of clockwise and anticlockwise directions following outward movement of the article 9, and disposed on the second bottom surface BS2 of the second bowl part 63.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The present invention relates to a vibrating feeder, and more particularly to a vibrating feeder that conveys an object while removing powder adhering to the object from the object. [Background technology]

[0002] Patent Document 1 discloses a powder remover in which tablets carried in through a receiving chute are conveyed by a vibrating feeder and discharged into a discharge chute. A gutter-shaped passage with a number of holes drilled in the bottom surface is provided between the receiving chute and the inlet of the vibrating feeder, and between the outlet of the vibrating feeder and the discharge chute. The vibrating feeder is composed of a bowl feeder equipped with a helix-shaped running plate having an inlet at the bottom and an outlet at the top. A number of suction holes are drilled in the circumferential surface of a cylinder to which the running plate of the bowl feeder is attached.

[0003] According to Patent Document 1, this powder remover can remove powder adhering to the tablet surface through multiple holes drilled in the bottom surface of a gutter-shaped passage between the receiving chute and the inlet of the vibrating feeder, and between the outlet of the vibrating feeder and the discharge chute, without chipping tablets. Furthermore, by configuring the vibrating feeder as a bowl feeder with a spiral-shaped running plate attached, the entire powder remover can be made compact. Furthermore, by drilling multiple suction holes in the circumferential surface of the cylinder to which the bowl feeder's running plate is attached, powder adhering to the tablet surface can be removed even during conveyance by the bowl feeder. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 8-141051 Summary of the Invention [Problem to be solved by the invention]

[0005] In the powder remover of Patent Document 1, most of the transport path for tablets as transported objects is configured with a spiral-shaped running plate. Powder removal from the transported object transported on this running plate is performed by sucking the powder toward the inside of the spiral shape using suction holes. Since the movement of the transported object is restricted by the spiral-shaped running plate, it is assumed that powder removal from the transported object is performed relatively stably. On the other hand, in this powder remover, if holes for removing powder were provided in the spiral-shaped running plate, the powder that passed through the holes would adhere to other transported objects located below. Therefore, providing holes in this running plate is impractical. Therefore, it is difficult to apply an efficient configuration of removing powder by dropping it downward to most of the transport path of this powder remover.

[0006] The present invention has been made in consideration of the above circumstances, and aims to provide a technique that can stably and efficiently remove powder adhering to an object being transported from the object. [Means for solving the problem]

[0007] A first aspect of the present invention is a vibratory feeder that conveys a thick object from upstream to downstream while removing powder adhering to the object from the object. The vibratory feeder includes a first bowl portion, a second bowl portion, an input portion, a vibrator, and at least one guide portion. The first bowl portion has a first bottom surface and a bowl opening above the first bottom surface, and is provided with a first outlet for conveying the object from the vibratory feeder. The second bowl portion is disposed inside the first bowl portion and has a second bottom surface with a plurality of through holes sized to prevent the object from passing through but allow powder to pass through, and a bowl opening above the second bottom surface. The second bottom surface of the second bowl portion has a central region and an outer peripheral region around the central region. The second bowl portion is provided with a second outlet between the outer peripheral region and the first outlet. The input portion is for feeding the object onto the central region of the second bottom surface of the second bowl portion. The vibrator vibrates the second bowl portion to move the transported object outward on the second bottom surface of the second bowl portion from the central region through the outer circumferential region to the second outlet. The at least one guide portion is disposed on the second bottom surface of the second bowl portion and serves to guide the transported object so that the transported object moves in a circular direction that is either a clockwise direction or a counterclockwise direction as the transported object moves outward.

[0008] A second aspect of the present invention is the vibratory feeder according to the first aspect, wherein the at least one guide portion includes a spiral guide portion that extends along a spiral that winds outward in a circumferential direction in a planar layout.

[0009] A third aspect is the vibrating feeder according to the second aspect, wherein the spiral guide portion is wound 360° or more.

[0010] A fourth aspect of the present invention is the vibratory feeder of the first aspect, wherein the at least one guide portion is a plurality of guide portions that define a conveying path for the conveyed objects on the second bottom surface of the second bowl portion. In a planar layout, the conveying path includes a spiral path that extends along a spiral that winds outward in a circumferential direction.

[0011] A fifth aspect of the present invention is a vibratory feeder according to the fourth aspect, wherein each of the plurality of guide sections has an inner surface facing the central region in a planar layout and an outer surface opposite the inner surface, and the plurality of guide sections include a first guide section and a second guide section adjacent to each other in a line along the conveying path. The line from the first guide section to the second guide section corresponds to the upstream-to-downstream direction. A portion of the outer surface of the first guide section and a portion of the inner surface of the second guide section face each other.

[0012] A sixth aspect is the vibrating feeder according to the fifth aspect, wherein the gap dimension between a part of the outer surface of the first guide portion and a part of the inner surface of the second guide portion is less than the thickness dimension of the conveyed object.

[0013] A seventh aspect of the present invention is the vibratory feeder according to any one of the first to sixth aspects, wherein the at least one guide portion is detachably attached to the second bowl portion.

[0014] Aspect 8 is the vibratory feeder according to any one of aspects 1 to 7, further comprising a drop slope disposed on an outer peripheral region of the second bottom surface of the second bowl section. The drop slope has a first end for allowing the conveyed objects to climb up the drop slope and a second end for allowing the conveyed objects that have climbed up the drop slope at the first end to fall onto the second bottom surface of the second bowl section. The second end is disposed higher from the second bottom surface of the second bowl section than the first end.

[0015] Aspect 9 is a vibratory feeder according to aspect 8, wherein in a planar layout, an extension of a straight line extending from the center of the central region of the second bottom surface of the second bowl portion to the downstream end of at least one guide portion overlaps with the drop slope.

[0016] Aspect 10 is a vibratory feeder described in any one of aspects 1 to 9, wherein the input section has an input opening facing the central region of the second bottom surface of the second bowl section and a lower end section surrounding the input opening.

[0017] An eleventh aspect of the present invention is the vibrating feeder according to the tenth aspect, wherein, in a planar layout, the shortest distance between the lower end of the feeding section and at least one guide section is smaller than the thickness of the conveyed object.

[0018] A twelfth aspect is the vibratory feeder according to the tenth or eleventh aspect, wherein the lower end of the feeding section has an effective portion and an ineffective portion. The gap dimension between the effective portion and the second bottom surface of the second bowl section is larger than the thickness dimension of the conveyed object, and the gap dimension between the ineffective portion and the second bottom surface of the second bowl section is smaller than the thickness dimension of the conveyed object.

[0019] Aspect 13 is a vibratory feeder described in aspect 12, wherein, in a planar layout, a straight line from the center of the central region of the second bottom surface of the second bowl section to the upstream end of at least one guide section overlaps with an ineffective portion of the lower end of the input section.

[0020] A fourteenth aspect of the present invention is the vibratory feeder according to any one of the first to thirteenth aspects, wherein the second bottom surface of the second bowl portion is gradually lowered with increasing distance from the central region. [Effects of the Invention]

[0021] According to the first aspect, at least one guide guides the transported object so that it moves in a circular motion. If the circular motion were to occur almost entirely, the transport path for the transported object would be a short, approximately linear path extending outward from the central region. However, by actively providing the circular motion, a transport path with a sufficient length and stability is ensured. By removing powder from the transported object during transport along this transport path, powder adhering to the transported object can be stably and efficiently removed from the transported object.

[0022] According to the second aspect, the transport path for the transported object includes a spiral path that extends along a spiral, which makes it possible to ensure a sufficient and stable length of the transport path compared to when the transport path is approximately linear.

[0023] According to the third aspect, a longer transport path for the transported object can be ensured.

[0024] According to the fourth aspect, the transport path can be defined by a plurality of guide portions instead of a single guide portion.

[0025] According to the fifth aspect, the flow of the transported object can smoothly transition from a path along the inner surface of the first guide portion to a path along the inner surface of the second guide portion.

[0026] According to the sixth aspect, it is possible to make it difficult for the object to enter between a part of the outer surface of the first guide portion and a part of the inner surface of the second guide portion.

[0027] According to the seventh aspect, at least one guide part can be removed during maintenance of the vibrating feeder.

[0028] According to the eighth aspect, a drop impact from the drop slope can be applied to the transported object. This drop impact can promote the removal of powder. Furthermore, the transported object may be turned over during the drop, in which case the powder can be removed more evenly from the surface of the transported object.

[0029] According to the ninth aspect, it becomes easier to reliably transport the object from the downstream of the transport path defined by at least one guide portion onto the drop slope.

[0030] According to the tenth aspect, the objects to be conveyed can be concentrated into the central region of the second bowl portion.

[0031] According to the eleventh aspect, it is possible to make it difficult for the transported object to enter between the lower end of the input portion and at least one guide portion in the planar layout.

[0032] According to the twelfth aspect, the transported object can be selectively fed from the feeding section into a specific angle range in the planar layout.

[0033] According to the thirteenth aspect, the transported object introduced from the central region is less likely to move toward the upstream end of at least one guide section, thereby preventing the transported object from accumulating near this end.

[0034] According to the fourteenth aspect, the outward movement of the transported object on the second bottom surface can be promoted. [Brief explanation of the drawings]

[0035] [Figure 1] FIG. 1 is a diagram showing the configuration of a tablet printing device having a bowl feeder. [Figure 2] FIG. 2 is a partial perspective view of the transfer conveyor shown in FIG. [Figure 3] FIG. 2 is a bottom view of one head shown in FIG. 1. [Figure 4] FIG. 2 is a control block diagram of the tablet printing device shown in FIG. 1. [Figure 5] FIG. 2 is a cross-sectional view of the bowl feeder according to the first embodiment. [Figure 6] 6 is a perspective view of the bowl feeder shown in FIG. 5, with the lid and feeding mechanism omitted. FIG. [Figure 7] FIG. 7 is a perspective view taken in a direction different from that of FIG. 6. [Figure 8] 6 is a top view of the bowl feeder shown in FIG. 5, with the lid and feeding mechanism omitted. FIG. [Figure 9] FIG. 6 is a bottom view of the bowl feeder shown in FIG. 5. [Figure 10] FIG. 6 is a top view of the lid shown in FIG. 5. [Figure 11] FIG. 10 is a partial top view showing the configuration of the inner bottom surface of the inner bottom portion of the inner bowl portion. [Figure 12] FIG. 2 is a partial top view showing the configuration of the surface of the drop slope. [Figure 13] FIG. 10 is a side view showing a first modified example of the shape of the transported object. [Figure 14] FIG. 14 is a cross-sectional view taken along line XIV-XIV in FIG. [Figure 15] FIG. 10 is a side view showing a second modified example of the shape of the transported object. [Figure 16] FIG. 16 is a cross-sectional view taken along line XVI-XVI in FIG. [Figure 17] FIG. 10 is a top view of a bowl feeder in a second embodiment, with the lid and the feeding mechanism not shown. [Figure 18] FIG. 11 is a bottom view showing the configuration of a sleeve of a feeding mechanism of a bowl feeder in a third embodiment. [Figure 19] 19 is a partial cross-sectional view of the sleeve and inner bowl portion taken along line XIX-XIX of FIG. 18. FIG. [Figure 20] FIG. 10 is a partial cross-sectional view schematically showing the configuration of an inner bowl portion in a fourth embodiment. [Figure 21] FIG. 11 is a top view of a bowl feeder in a fifth embodiment, with the lid and feeding mechanism not shown. DETAILED DESCRIPTION OF THE INVENTION

[0036] Hereinafter, embodiments will be described with reference to the drawings. Some figures show an xyz Cartesian coordinate system, in which the z direction is the direction opposite to the direction of gravity (i.e., upward), and the xy plane is a horizontal plane. Some figures show an Xt-Yt-Zt Cartesian coordinate system, but the Xt, Yt, and Zt directions of this Cartesian coordinate system are shown merely to make the directional relationships between the figures easier to understand and are unrelated to the direction of gravity. In addition, in this specification, a "spiral" refers to a two-dimensional curve that moves away from the center as it turns. When a component is defined as having a spiral shape in a planar layout (i.e., projection onto the xy plane), this definition limits the planar layout but does not limit the shape of the component in a direction perpendicular to the planar layout (i.e., z direction).

[0037] <Configuration of tablet printing device with bowl feeder> First, the configuration of a tablet printing apparatus as an example of an apparatus to which the bowl feeder 11 (vibration feeder) of any of the following embodiments 1 to 5 can be applied will be described below with reference to Figures 1 to 4. The configuration of the bowl feeder 11 (vibration feeder) will be described in the following embodiments 1 to 5.

[0038] FIG. 1 is a diagram showing the configuration of a tablet printing apparatus 1. This tablet printing apparatus 1 is an apparatus that prints images such as a product name, product code, company name, and logo mark on both the front and back sides of each of a plurality of tablets (conveyed objects) 9 (also referred to as conveyed objects 9 in the following embodiments 1 to 5). The tablets 9 may be plain tablets (plain tablets), or coated tablets such as sugar-coated tablets and film-coated tablets (FC tablets). The tablets 9 may also be capsules, including hard capsules and soft capsules. The "tablets" in the present invention are not limited to pharmaceutical tablets, but may also be tablets used as health foods or tablet confections such as Ramune soda.

[0039] As shown in Figure 1, the tablet printing apparatus 1 includes a supply mechanism 10, a first drum 15, a second drum 20, a transport conveyor 25, a first camera 30, a printing unit 35, a second camera 40, a drying mechanism 45, an inversion mechanism 50, a discharge mechanism 55, and a control unit 100.

[0040] The supply mechanism 10 is a mechanism that supplies a plurality of tablets 9 fed into the tablet printing apparatus 1 to the first drum 15. The supply mechanism 10 has a bowl feeder 11 (also referred to as a vibrating feeder 11), a first chute 12, a supply conveyor 13, and a second chute 14.

[0041] Bowl feeder 11 moves the plurality of tablets 9 fed therein by vibration and supplies them to first chute 12. First chute 12 is a supply path connecting a discharge port 630 of bowl feeder 11, which will be described later, and supply conveyor 13.

[0042] The supply conveyor 13 is a mechanism for transporting the tablets 9 from the first chute 12 to the second chute 14. The supply conveyor 13 has two pulleys 131 and a circular supply belt 132 stretched around the two pulleys 131. One of the two pulleys 131 rotates by power obtained from a motor (not shown). This causes the supply belt 132 to rotate in the direction indicated by the arrow in FIG. 1. The other pulley 131 is rotated in response to the rotation of the supply belt 132. In addition, a partition plate extending along the boundaries of the rows of tablets 9 is provided above the supply belt 132. The tablets 9 supplied from the first chute 12 are transported downstream in the transport direction by the rotation of the supply belt 132 while being kept aligned in multiple rows by the partition plate.

[0043] The second chute 14 extends linearly between the supply conveyor 13 and the first drum 15. The second chute 14 has multiple horizontal supply paths. A plurality of tablets 9 supplied from the supply conveyor 13 are supplied to each supply path of the second chute 14. The tablets 9 in the second chute 14 are pushed by the following tablets 9 conveyed by the supply conveyor 13, and are conveyed downstream in the conveying direction. Then, the tablets 9 are supplied to the first drum 15 from the end of the second chute 14 on the downstream side in the conveying direction.

[0044] The first drum 15 is a mechanism that holds and conveys a plurality of tablets 9 supplied from the second chute 14 at regular intervals in the conveying direction. The first drum 15 has a substantially cylindrical outer circumferential surface centered on a first axis O1 parallel to the width direction. A motor (not shown) is connected to the first drum 15. When the motor is driven, the first drum 15 rotates in the direction of the arrow in FIG. 1 around the first axis O1. The first drum 15 conveys the tablets 9 from a first transfer position P1 near its upper end to a second transfer position P2 adjacent to the second drum 20.

[0045] As shown in FIG. 1, the first drum 15 has a drum body 16 and a retaining ring 17. The drum body 16 has a cylindrical outer peripheral surface centered on a first axis O1. The drum body 16 is formed of a metal such as stainless steel. The retaining ring 17 is attached to the outer peripheral surface of the drum body 16. Specifically, a plurality of retaining rings 17 are arranged at widthwise positions corresponding to the respective rows of tablets 9. The retaining ring 17 is formed of a resin such as polyacetal.

[0046] The outer peripheral surface of each retaining ring 17 has a plurality of recessed pockets 18. The plurality of pockets 18 are provided at regular intervals in the circumferential direction centered on the first axis O1. The retaining ring 17 also has suction holes 19 at the bottom of each pocket 18 for suctioning the tablets 9. The suction holes 19 are through-holes that pass through the retaining ring 17.

[0047] The first drum 15 is connected to a suction mechanism (not shown). When the suction mechanism is operated, gas is sucked out from the internal space of the first drum 15 located in the angular range between the first delivery position P1 and the second delivery position P2. This causes the internal space to have a negative pressure lower than atmospheric pressure. Negative pressure is also generated in the suction holes 19 communicating with the internal space. The multiple tablets 9 supplied from the second chute 14 are sucked and held in the suction holes 19 of the retaining ring 17 by this negative pressure.

[0048] The tablets 9 supplied from the second chute 14 are accommodated one by one in the pockets 18 and adsorbed and held in the suction holes 19. At this time, the tablets 9 are pressed by the pressing mechanism 141 and guided into the pockets 18 of the retaining ring 17. As a result, the spacing between the tablets 9 in the conveying direction becomes a predetermined spacing corresponding to the spacing between the pockets 18. While being adsorbed and held in the suction holes 19 in the pockets 18, each tablet 9 is conveyed from the first delivery position P1 to the second delivery position P2 by the rotation of the first drum 15. Then, when the tablet 9 passes the second delivery position P2, it moves out of the angle range of the internal space maintained at the negative pressure, and the adsorption of the tablet 9 is released. As a result, the tablet 9 is transferred from the first drum 15 to the second drum 20.

[0049] The second drum 20 is a mechanism that transports the tablets 9 transferred from the first drum 15 to the transfer conveyor 25. The second drum 20 has a substantially cylindrical outer peripheral surface centered on a second axis O2 parallel to the width direction. The outer diameters of the first drum 15 and the second drum 20 may be substantially the same. However, the outer diameters of the first drum 15 and the second drum 20 may be different. A motor (not shown) is connected to the second drum 20. When the motor is driven, the second drum 20 rotates around the second axis O2 in the opposite direction to the first drum 15. The second drum 20 transports the tablets 9 from a second transfer position P2 adjacent to the first drum 15 to a third transfer position P3 adjacent to the transfer conveyor 25. The height of the third transfer position P3 is higher than the heights of the first transfer position P1 and the second transfer position P2.

[0050] As shown in FIG. 1, the second drum 20 has a drum body 21 and a retaining ring 22. The drum body 21 has a cylindrical outer peripheral surface centered on the second axis O2. The drum body 21 is formed of a metal such as stainless steel. The retaining ring 22 is attached to the outer peripheral surface of the drum body 21. Specifically, a plurality of retaining rings 22 are arranged at widthwise positions corresponding to the respective rows of tablets 9. The retaining ring 22 is formed of a resin such as silicone.

[0051] Each retaining ring 22 has a plurality of suction holes 24. The suction holes 24 are through holes that penetrate the retaining ring 22. The second drum 20 is also connected to a suction mechanism (not shown). When the suction mechanism is operated, gas is sucked out from the internal space of the second drum 20 located in the angular range between the second delivery position P2 and the third delivery position P3. This causes the internal space to have a negative pressure lower than atmospheric pressure. Negative pressure is also generated in the suction holes 24 that communicate with the internal space. The plurality of tablets 9 delivered from the first drum 15 are sucked and held in the suction holes 24 of the retaining ring 22 by this negative pressure.

[0052] The tablet 9 held by suction in the suction holes 24 is transported from the second delivery position P2 to the third delivery position P3 by the rotation of the second drum 20. When the tablet 9 passes the third delivery position P3, it moves out of the angle range of the internal space maintained at the negative pressure, and the suction of the tablet 9 is released. As a result, the tablet 9 is delivered from the second drum 20 to the transport conveyor 25.

[0053] In this way, the plurality of tablets 9 supplied from the supply mechanism 10 are transported to the transport conveyor 25 via two drums, the first drum 15 and the second drum 20. The first drum 15 holds the plurality of tablets 9 spaced apart in the transport direction. The second drum 20 transports the tablets 9 to the transport conveyor 25 while maintaining the spacing in the transport direction. At this time, the transport direction (direction of rotation) of the tablets 9 is reversed between the first drum 15 and the second drum 20. This allows the tablets 9 to be sent from the second drum 20 to the transport conveyor 25 in accordance with the direction of operation of the transport conveyor 25.

[0054] The transport conveyor 25 is a mechanism that transports a plurality of tablets 9 delivered from the second drum 20 while suction-holding them. The transport conveyor 25 has a pair of pulleys 26 and a circular transport belt 27 stretched between the pair of pulleys 26. One of the pair of pulleys 26 is rotated by power obtained from a motor (not shown). This causes the transport belt 27 to rotate in the direction of the arrow in FIG. 1. The other of the pair of pulleys 26 is rotated in response to the rotation of the transport belt 27.

[0055] FIG. 2 is a partial perspective view of the transport conveyor 25. As shown in FIG. 2, a plurality of suction holes 29 are formed in the transport belt 27. The plurality of suction holes 29 are arranged at intervals in the transport direction and the width direction. Each suction hole 29 is a through-hole that penetrates the transport belt 27. The transport conveyor 25 also has a suction mechanism (not shown) that sucks out gas from the space inside the transport belt 27. When the suction mechanism is operated, the space inside the transport belt 27 becomes negative pressure, which is lower than atmospheric pressure. The plurality of tablets 9 are sucked and held one by one in the suction holes 29 by the negative pressure.

[0056] In this way, the plurality of tablets 9 are held on the surface of the conveyor belt 27 in a state aligned in the conveying direction and the width direction. The conveyor 25 then rotates the conveyor belt 27 to convey the plurality of tablets 9 along the circular conveying path. Below four heads 36 (described later), the plurality of tablets 9 are held on the upper surface of the conveyor belt 27 and conveyed horizontally. Above a discharge mechanism 55 (described later), the plurality of tablets 9 are held on the lower surface of the conveyor belt 27 and conveyed horizontally.

[0057] As shown in FIG. 2, the surface of the conveyor belt 27 has a first region A1 that holds the tablets 9 before they are inverted by the inverting mechanism 50, and a second region A2 that holds the tablets 9 after they are inverted. The first region A1 and the second region A2 are adjacent to each other in the width direction. In the illustrated example, the first region A1 and the second region A2 are each provided with three rows of suction holes 29 in the width direction. The tablets 9 supplied by the above-described supply mechanism 10, first drum 15, and second drum 20 are suction-held by the suction holes 29 in the first region A1. Furthermore, the tablets 9 printed on both sides are discharged to the discharge mechanism 55 through the suction holes 29 in the second region A2.

[0058] The first camera 30 is a processing unit for photographing the tablets 9 before printing. The first camera 30 is located downstream of the third delivery position P3 and upstream of the printing unit 35 on the conveying path. The first camera 30 extends in the width direction across both the first area A1 and the second area A2. For example, a line sensor in which imaging elements such as CCD or CMOS are arranged in the width direction is used for the first camera 30. The first camera 30 photographs the tablets 9 conveyed by the conveyor belt 27. The images acquired by photographing are transmitted from the first camera 30 to the control unit 100 described below. Based on the images obtained from the first camera 30, the control unit 100 detects the presence or absence of tablets 9 in each suction hole 29, the position of the tablets 9, and the posture of the tablets 9. Based on the images obtained from the first camera 30, the control unit 100 also inspects each tablet 9 for defects such as chips.

[0059] The printing unit 35 is a processing unit that prints images on the surfaces of the tablets 9 transported by the conveyor belt 27 using an inkjet method. As shown in FIG. 1, the printing unit 35 has, for example, four heads 36. The four heads 36 are located above the conveyor belt 27 and arranged in a row along the transport direction of the tablets 9. Each head 36 extends in the width direction, spanning both the first area A1 and the second area A2. The four heads 36 eject ink droplets of different colors (e.g., cyan, magenta, yellow, and black) toward the tablets 9. A multicolor image is then recorded on the surface of the tablets 9 by superimposing the monochromatic images formed by these colors. The ink ejected from each head 36 is edible ink made from ingredients approved by the Japanese Pharmacopoeia, the Food Sanitation Act, etc.

[0060] FIG. 3 is a bottom view of one head 36. In FIG. 3, the conveyor belt 27 and the plurality of tablets 9 held on the conveyor belt 27 are indicated by two-dot chain lines. As shown enlarged in FIG. 3, the bottom surface of the head 36 is provided with a plurality of nozzles 37 capable of ejecting ink droplets. The plurality of nozzles 37 are arranged two-dimensionally in the conveyance direction and width direction on the bottom surface of the head 36. The nozzles 37 are arranged with their positions shifted in the width direction. By arranging the plurality of nozzles 37 two-dimensionally in this way, the positions of the nozzles 37 in the width direction can be made close to each other. However, the plurality of nozzles 37 may also be arranged in a line along the width direction.

[0061] The ink droplets are ejected from the nozzle 37 by a so-called piezo method, in which a voltage is applied to a piezo element to deform it, thereby pressurizing and ejecting the ink inside the nozzle 37. However, the ink droplets may also be ejected by a so-called thermal method, in which electricity is applied to a heater to heat and expand the ink inside the nozzle 37, thereby ejecting the ink.

[0062] The second camera 40 is a processing unit for photographing the tablets 9 after printing. The second camera 40 is located downstream of the printing unit 35 on the conveying path and upstream of the drying mechanism 45 on the conveying path. The second camera 40 extends in the width direction across both the first area A1 and the second area A2. The second camera 40 uses, for example, a line sensor in which imaging elements such as CCD or CMOS are arranged in the width direction. The second camera 40 photographs the plurality of tablets 9 conveyed by the conveyor belt 27. The images acquired by photographing are transmitted from the second camera 40 to the control unit 100, which will be described later. The control unit 100 inspects the quality of the images printed on the tablets 9 based on the images obtained from the second camera 40.

[0063] The drying mechanism 45 is a mechanism for drying ink adhering to the tablet 9. The drying mechanism 45 is located downstream of the second camera 40 on the conveying path and upstream of the inversion mechanism 50 and discharge mechanism 55 described below on the conveying path. The drying mechanism 45 extends in the width direction across both the first area A1 and the second area A2. The drying mechanism 45 may be, for example, a hot air supply mechanism that blows heated gas (hot air) toward the tablet 9 being conveyed by the conveyor belt 27. The ink adhering to the tablet 9 is dried by the hot air and fixed to the front or back surface of the tablet 9.

[0064] The inversion mechanism 50 inverts the tablets 9 conveyed by the conveyor belt 27 and moves the tablets 9 from the first region A1 to the second region A2. The inversion mechanism 50 is located downstream of the drying mechanism 45 on the conveying path. The inversion mechanism 50 has multiple pairs of inclined drums 51 lined up in the width direction. Each inclined drum 51 has a conical holding surface. One of the pair of inclined drums 51 rotates while adsorbing the tablets 9 conveyed in the first region A1 to the holding surface, and transfers the tablets 9 to the other inclined drum 51. The other inclined drum 51 rotates while adsorbing the tablets 9 received from the one inclined drum 51 to the holding surface, and transfers the tablets 9 to the second region A2. As a result, the tablets 9 are inverted and moved from the first region A1 to the second region A2.

[0065] The tablet 9 transported from the supply mechanism 10 to the transport conveyor 25 via the first drum 15 and the second drum 20 is first held in the first area A1 of the transport belt 27. The tablet printing apparatus 1 then transports the tablet 9 while holding it in the first area A1, and performs the following processes on one side of the tablet 9: photographing by the first camera 30, printing by the printing unit 35, photographing by the second camera 40, and drying by the drying mechanism 45. Next, the inversion mechanism 50 inverts the tablet 9 and moves it from the first area A1 to the second area A2. Thereafter, the tablet printing apparatus 1 transports the tablet 9 while holding it in the second area A2, and performs the following processes on the other side of the tablet 9: photographing by the first camera 30, printing by the printing unit 35, photographing by the second camera 40, and drying by the drying mechanism 45.

[0066] The discharge mechanism 55 is a mechanism for discharging a plurality of tablets 9 printed on both sides from the transport conveyor 25. The discharge mechanism 55 is located downstream of the transport path from the drying mechanism 45. The discharge mechanism 55 discharges the tablets 9 held in the second area A2 of the transport belt 27 while separating them into defective tablets and non-defective tablets.

[0067] The control unit 100 is a means for controlling the operation of each unit in the tablet printing apparatus 1. FIG. 4 is a control block diagram of the tablet printing apparatus 1. As conceptually shown in FIG. 4, the control unit 100 is composed of a computer having a processor 101 such as a CPU, a memory 102 such as RAM, and a storage unit 103 such as a hard disk drive. A computer program CP for carrying out the conveyance and printing process of the tablets 9 is stored in the storage unit 103.

[0068] As shown in FIG. 4, the control unit 100 is electrically connected to the bowl feeder 11, supply conveyor 13, first drum 15, second drum 20, transport conveyor 25, first camera 30, printing unit 35, second camera 40, drying mechanism 45, reversing mechanism 50, and discharge mechanism 55.

[0069] The control unit 100 temporarily loads the computer program CP and data stored in the storage unit 103 into the memory 102, and the processor 101 performs arithmetic processing based on the computer program CP, thereby controlling the operation of each of the above-mentioned units. This allows the transportation of multiple tablets 9 and the printing process for each tablet 9 to proceed.

[0070] The above has described the configuration of the tablet printing apparatus 1. Next, the specific configuration of the bowl feeder 11 of the tablet printing apparatus 1 will be described in the following embodiments 1 to 5. Note that the use of the bowl feeder 11 is not limited to the tablet printing apparatus.

[0071] <First Embodiment> (Bowl feeder configuration overview) FIG. 5 is a cross-sectional view of bowl feeder 11 (also referred to as vibrating feeder 11) in embodiment 1. FIG. 6 is a perspective view of bowl feeder 11 shown in FIG. 5, with lid 64 and feeding mechanism 700 not shown. FIG. 7 is a perspective view from a different direction than FIG. 6. FIG. 8 is a top view of bowl feeder 11 shown in FIG. 5, with lid 64 and feeding mechanism 700 not shown. FIG. 9 is a bottom view of bowl feeder 11 shown in FIG. 5. FIG. 10 is a top view of lid 64 shown in FIG. 5. In addition to bowl feeder 11, FIGS. 5 to 9 also show first chute 12 described above. First chute 12 may be modified or omitted depending on the application of bowl feeder 11.

[0072] The vibrating feeder 11 conveys the object 9 from upstream (a central region RC described later) to downstream (a discharge region 639 described later) while removing powder adhering to the object 9, which has a thickness. In the example shown in FIGS. 1 to 3, the object 9 is a tablet having a circular shape in a planar layout and a thickness perpendicular to the circular shape. The tablet thickness is typically 1 mm to 8 mm. In this embodiment and other embodiments described later, the object 9 is not limited to a tablet, but may be anything that can adhere to or generate powder. For example, the object 9 may be an industrial product such as a screw, or may be a natural nut that is not artificially formed. Modified shapes of the object 9 will be described later with reference to FIGS. 13 to 16.

[0073] Bowl feeder 11 has outer bowl portion 62 (first bowl portion), inner bowl portion 63 (second bowl portion), feeding mechanism 700 (FIG. 5), vibrator 68 (FIG. 5), and spiral guide portion 81. Feeding mechanism 700 has sleeve 701 (feeding portion), and may further have tube 702 with sleeve 701 attached to the tip thereof.

[0074] Outer bowl portion 62 has a bottom surface BS1 (first bottom surface) and a bowl opening above bottom surface BS1. Outer bowl portion 62 is provided with an outer carry-out port 620 (first carry-out port) for carrying out conveyed objects 9 from bowl feeder 11.

[0075] The inner bowl portion 63 is disposed inside the outer bowl portion 62. The inner bowl portion 63 has a bottom surface BS2 (second bottom surface) and a bowl opening above the bottom surface BS2. As shown in FIG. 11 , the bottom surface BS2 is provided with a plurality of through holes 90 that are large enough to prevent the object 9 from passing through while allowing the powder to pass through. The maximum dimension of the through holes 90 in the planar layout may be smaller than the thickness of the object. The bottom surface BS2 of the inner bowl portion 63 has a central region RC and an outer peripheral region RO around the central region RC. The inner bowl portion 63 is provided with an inner unloading port 630 (second unloading port) between the outer peripheral region RO and the outer unloading port 620.

[0076] The sleeve 701 is for loading the object 9 onto the central region RC of the bottom surface BS2 of the inner bowl portion 63. The sleeve 701 has an loading opening OC facing the central region RC of the bottom surface BS2 of the inner bowl portion 63, and a lower end portion surrounding the loading opening OC. The material of the sleeve 701 may include an elastic body. The elastic body may include rubber. The rubber is, for example, silicone rubber or urethane rubber. The object 9 may be supplied to the sleeve 701 via a pipe 702.

[0077] The vibrator 68 vibrates the inner bowl portion 63 to move the load 9 outward on the bottom surface BS2 of the inner bowl portion 63 from the central region RC to the inner discharge port 630 via the outer peripheral region RO.

[0078] The spiral guide 81 guides the transported object 9 so that the transported object 9 moves in a circular direction, either clockwise or counterclockwise, as the transported object 9 moves outward. In FIG. 8, the circular direction is shown as clockwise when viewed from above. As a variant, the circular direction may be counterclockwise.

[0079] The spiral guide portion 81 extends along a spiral that winds outward in a circumferential direction in a planar layout. As shown in FIG. 8, the spiral guide portion 81 may wind 360° or more.

[0080] The swirl guide portion 81 is disposed on the bottom surface BS2 of the inner bowl portion 63. The swirl guide portion 81 may be detachably attached to the inner bowl portion 63. Specifically, the swirl guide portion 81 may be attached to the inner bowl portion 63 by a fastening member. The fastening member may be, for example, a screw.

[0081] The thickness dimension of the spiral guide portion 81 (specifically, the maximum dimension in the z direction) is preferably at least half the thickness dimension. The thickness dimension of the spiral guide portion 81 may be smaller than the height dimension of the inner wall portion 632 of the inner bowl portion. In a planar layout (in other words, projection onto the xy plane), the shortest distance between the lower end of the sleeve 701 (FIG. 5) and the spiral guide portion 81 may be smaller than the thickness dimension of the transported object 9.

[0082] The bowl feeder 11 may have a drop slope 634. The drop slope 634 is disposed on the outer peripheral region RO of the bottom surface BS2 of the inner bowl portion 63. The drop slope 634 has an upstream end ED1 (first end) for carrying the conveyed objects 9 up, and a downstream end ED2 (second end) for carrying the conveyed objects 9 that have run up the drop slope 634 at the upstream end ED1 and then dropping them onto the bottom surface BS2 of the inner bowl portion 63. The downstream end ED2 is disposed higher from the bottom surface BS2 of the inner bowl portion 63 than the upstream end ED1. As shown in FIG. 8 , in the planar layout, an extension line LG of a straight line extending from the center CT of the central region RC of the bottom surface BS2 of the inner bowl portion 63 to the downstream end EDS of the spiral guide portion 81 may overlap the drop slope 634. As shown in FIG. 12, the surface of the drop slope 634 may be provided with a plurality of through holes 91 having a size that allows the powder to pass through while preventing the transported object 9 from passing through.

[0083] The bowl feeder 11 may have a discharge slope 633. The discharge slope 633 is disposed on the outer peripheral region RO of the bottom surface BS2 of the inner bowl portion 63. The discharge slope 633 has an upstream end ED3 for carrying the conveyed objects 9 up and a downstream end ED4 for dropping the conveyed objects 9 that have run up onto the discharge slope 633 at the upstream end ED3 onto the bottom surface BS2 of the inner bowl portion 63. The upstream portion of the discharge slope 633 has the upstream end ED3, and the downstream portion of the discharge slope 633 has the downstream end ED4, and this downstream portion constitutes a discharge area 639. The discharge area 639 is disposed higher from the bottom surface BS2 of the inner bowl portion 63 than the upstream end ED3. A through hole similar to the through hole 91 of the drop slope 634 ( FIG. 12 ) may be provided in the surface of the discharge slope 633. At least some of the multiple transported objects 9 that reach the discharge area 639 pass through the inner transport outlet 630 and the outer transport outlet 620 in that order and are transported to the first chute 12. The transported objects 9 that are not transported fall from the downstream end ED4 to the bottom surface BS2 of the inner bowl section 63. The fallen transported objects 9 climb up the upstream end ED1 of the drop slope 634 again.

[0084] FIG. 13 is a side view showing a transported object 9A according to a first modified example of the shape of the transported object 9. FIG. 14 is a cross-sectional view taken along line XIV-XIV in FIG. 13. As mentioned above, the Xt, Yt, and Zt directions are shown to facilitate understanding of the directional relationships between the drawings and are unrelated to the direction of gravity. The transported object 9A has a roughly elliptical shape in its planar layout (FIG. 13: projection onto the XtYt plane perpendicular to the Zt direction). The elliptical shape has a major axis (indicated by a dashed-dotted line in the figure). FIG. 14 shows a cross section perpendicular to the major axis of the ellipse and passing through the center of the ellipse. The thickness dimension t of the transported object 9A corresponds to its maximum dimension in the Zt direction. In this cross section, the transported object 9B may have a roughly rectangular shape, in which case the thickness dimension t is the dimension of the shorter side of the rectangle. The ellipse may be a circle, and the rectangle may be a square.

[0085] FIG. 15 is a side view showing a second modified example of the shape of the transported object 9, that is, a transported object 9B. FIG. 16 is a cross-sectional view taken along line XVI-XVI in FIG. 15. The transported object 9A has an approximately elliptical shape in a planar layout (FIG. 15: projection onto the XtYt plane perpendicular to the Zt direction). The elliptical shape has a major axis (indicated by a dashed line in the figure). FIG. 16 shows a cross section perpendicular to the major axis of the ellipse and passing through the center of the ellipse. The thickness dimension t of the transported object 9B corresponds to the maximum dimension in the Zt direction. In this cross section, the transported object 9B may have an approximately elliptical shape, in which case the thickness dimension t is the dimension of the minor axis of the ellipse. Note that the ellipses in either or both of FIG. 15 and FIG. 16 may be circular.

[0086] To define the thickness dimension in a general way so that the thickness dimension t can be uniquely determined for any shape of transported object, the thickness dimension is the maximum dimension in the direction in which the maximum dimension is minimized when the maximum dimensions in each direction are taken into consideration. In the case of transported objects 9A and 9B, the maximum dimension in the Zt direction corresponds to the thickness dimension t. Generally speaking, the direction in which the maximum dimension is minimized is not limited to one. The thickness dimension t is, for example, between 1 mm and 8 mm, but is not necessarily limited to this range.

[0087] (Summary of effects) According to the first embodiment, the spiral guide 81 guides the transported object 9 so that it moves in a circular motion. If almost no circular motion were to occur, the transport path of the transported object 9 would be a short, approximately linear path extending outward from the central region RC (FIG. 8). However, by actively providing the circular motion, a transport path PS (FIG. 8) having a sufficient length and stability is ensured. By removing powder from the transported object 9 during transport along this transport path PS, powder adhering to the transported object 9 can be removed from the transported object 9 in a stable and efficient manner.

[0088] The spiral guide 81 extends along a spiral that winds outward in a circumferential direction in a planar layout. As a result, the transport path PS for the transported object includes a spiral path that extends along the spiral. Therefore, compared to when the transport path PS is approximately linear, the length of the transport path PS can be ensured sufficiently and stably.

[0089] The spiral guide portion 81 may be wound 360° or more, thereby ensuring a longer transport path PS for the transported object 9.

[0090] The spiral guide portion 81 may be removably attached to the inner bowl portion 63. This allows the spiral guide portion 81 to be removed when performing maintenance on the bowl feeder 11.

[0091] The downstream end ED2 of the drop slope 634 is positioned higher from the bottom surface BS2 of the inner bowl portion 63 than the upstream end ED1 of the drop slope 634. This allows a drop impact from the drop slope to be applied to the transported object 9. This drop impact can promote the removal of powder. Furthermore, the transported object 9 may be turned over during the drop, in which case the powder can be removed more evenly from the surface of the transported object 9.

[0092] In the planar layout, an extension line LG (FIG. 8) of a straight line extending from the center CT of the central region RC of the bottom surface BS2 of the inner bowl portion 63 toward the downstream end EDS of the spiral guide portion 81 overlaps with the drop slope 634. This makes it easier to reliably transport the transported object 9 from the downstream of the transport path PS defined by the spiral guide portion 81 onto the drop slope 634.

[0093] Sleeve 701 (Fig. 5) has a feed opening OC (Fig. 5) facing a central region RC (Fig. 8) of the bottom surface BS2 of inner bowl portion 63, and a lower end portion surrounding the feed opening OC. This allows transported objects 9 to be fed intensively into the central region RC of inner bowl portion 63.

[0094] In the planar layout, the shortest distance between the lower end of sleeve 701 (FIG. 5) and spiral guide portion 81 may be smaller than the thickness of transported object 9. This makes it difficult for transported object 9 to enter between lower end PE of sleeve 701 and spiral guide portion 81 in the planar layout. To further enhance this effect, it is preferable that the shortest distance be smaller than half the thickness of transported object 9.

[0095] (Details of bowl feeder) Next, although it overlaps with the above description, the bowl feeder 11 will be described in detail below.

[0096] As shown in FIG. 5, bowl feeder 11 has a main body portion 61, an outer bowl portion 62, an inner bowl portion 63, and a lid 64, and is connected to a suction mechanism 65 and a gas supply mechanism 66.

[0097] 5 to 7, main body portion 61 is cylindrical. The lower surface of outer bowl portion 62 is fixed to the upper surface of main body portion 61. Furthermore, inner bowl portion 63 is disposed inside outer bowl portion 62. Outer bowl portion 62 and inner bowl portion 63 are fixed to each other by a fixing mechanism such as a screw mechanism (not shown).

[0098] Main body portion 61 has a vibrator inside. As a result, when bowl feeder 11 is driven, the vibration of the vibrator vibrates outer bowl portion 62 and inner bowl portion 63. In other words, the vibrator included in main body portion 61 vibrates outer bowl portion 62 and inner bowl portion 63.

[0099] 5 to 9, outer bowl portion 62 is cup-shaped and open at the top. Outer bowl portion 62 has outer bottom portion 621, outer wall portion 622, a plurality of lower discharge ports 623, a plurality of side discharge ports 624, and outer carry-out port 620.

[0100] The outer bottom portion 621 is a disk-shaped portion that extends horizontally. The outer bottom portion 621 covers the lower side of the inner bowl portion 63. The center of the lower surface of the outer bottom portion 621 is fixed to the main body portion 61. The outer wall portion 622 is a cylindrical portion that extends upward from the edge of the outer bottom portion 621. The outer wall portion 622 covers the side of the inner bowl portion 63.

[0101] Lower discharge port 623 is a cylindrical discharge port extending downward from outer bottom portion 621. Lower discharge port 623 connects the internal space of outer bowl portion 62 with the outside, and discharges powder within the internal space of outer bowl portion 62 to the outside. As shown in Fig. 9, outer bowl portion 62 has four lower discharge ports 623. The four lower discharge ports 623 are arranged at equal intervals in the circumferential direction outside the fixed point between outer bottom portion 621 and main body portion 61.

[0102] As shown in Figures 6 to 9, side discharge ports 624 are cylindrical discharge ports extending outward from outer wall portion 622. Side discharge ports 624 communicate the internal space of outer bowl portion 62 with the outside, and discharge powder within the internal space of outer bowl portion 62 to the outside. As shown in Figure 9, outer bowl portion 62 has four side discharge ports 624. The four side discharge ports 624 are arranged at equal intervals in the circumferential direction of outer bowl portion 62.

[0103] Outer discharge port 620 is a through-hole provided in the side surface of outer bowl portion 62. Specifically, outer discharge port 620 is a through-hole provided in outer wall portion 622. Outer discharge port 620 does not have to be a through-hole, and may be a notch extending downward from the upper end of outer bowl portion 62.

[0104] 5 to 8, inner bowl portion 63 is cup-shaped and open at the top. Inner bowl portion 63 is disposed inside outer bowl portion 62. Inner bowl portion 63 has an inner bottom portion 631, an inner wall portion 632, a discharge slope 633, a drop slope 634, and an inner discharge port 630.

[0105] The inner bottom 631 is a disk-shaped portion that extends horizontally. Note that the inner bottom 631 does not have to be flat. The inner bottom 631 may be, for example, curved with a raised center. A plurality of through holes 90 are provided in the inner bottom 631. The plurality of through holes 90 may be evenly arranged throughout the inner bottom 631. The inner bottom 631 may be formed of a mesh material. Specifically, the inner bottom 631 may be formed by stretching a filamentary material such as wire in multiple directions. The gaps in the mesh material correspond to the through holes 90. By using a mesh configuration, the area ratio of the through holes 90 to the inner bottom 631 can be easily increased. This makes it easier for powder to fall from the inner bottom 631.

[0106] The inner wall portion 632 is a cylindrical portion that extends upward from the edge of the inner bottom portion 631. The inner wall portion 632 is disposed inside the outer wall portion 622 with a gap between it and the inner circumferential surface of the outer wall portion 622.

[0107] The inner discharge port 630 is a cutout provided in the side surface of the inner bowl portion 63. Specifically, the inner discharge port 630 is a cutout extending downward from the upper end of the inner wall portion 632. The inner discharge port 630 may not be a cutout but may be a through-hole. The inner discharge port 630 is positioned so as to overlap with the outer discharge port 620.

[0108] The unloading slope 633 is a slope provided on the inner bottom 631. The unloading slope 633 extends circumferentially (clockwise in a top view) from the inner bottom 631 along the inner wall 632 from the inner bottom 631 to the inner unloading opening 630 from below to above. The width of the unloading slope 633 in the radial direction is approximately constant. The upstream end ED3 of the unloading slope 633 smoothly connects to the inner bottom 631. On the other hand, the downstream end ED4 of the unloading slope 633 is located above the inner bottom 631 and forms a step from the inner bottom 631. A portion of the unloading slope 633, including the downstream end ED4, forms a substantially horizontal unloading area 639 along the lower end of the inner unloading opening 630. The unloading slope 633 is inclined at a substantially constant gradient between the upstream end ED3 and the unloading area 639. The discharge slope 633 is formed, for example, from a perforated metal with a plurality of through holes (not shown) evenly distributed over the entire area. Perforated metal is more rigid than mesh materials, making it suitable for use as a material for three-dimensional components such as slopes.

[0109] The drop slope 634 is a slope provided on the inner bottom 631. The drop slope 634 extends circumferentially (clockwise in a top view) from the inner bottom 631 upward along the inner wall 632 from the inner bottom 631 toward the upper end. The radial width of the drop slope 634 is substantially constant. The upstream end ED1 of the drop slope 634 smoothly connects to the inner bottom 631. Meanwhile, the downstream end ED2 of the drop slope 634 is located above the inner bottom 631 in the circumferential direction and forms a step with the inner bottom 631. The drop slope 634 is inclined at a substantially constant gradient over its entire area. The drop slope 634 is formed, for example, from a punched metal having a plurality of through holes 91 ( FIG. 12 ) evenly arranged over its entire area.

[0110] With this configuration, when bowl feeder 11 is driven, a large number of conveyed objects 9 are placed on inner bottom portion 631 of bowl feeder 11, and outer bowl portion 62 and inner bowl portion 63 are vibrated by the vibrator of main body portion 61. This causes outer bowl portion 62 and inner bowl portion 63 to vibrate. This vibration causes outward movement (movement outward in the radial direction) and circular movement (movement in the clockwise direction in this embodiment) of conveyed objects 9 on inner bottom portion 631.

[0111] This movement causes a portion of the transported object 9 on the inner bottom 631 to climb from the upstream end ED1 of the fall slope 634 along the inner wall 632, and when it reaches the downstream end ED2 of the fall slope 634, it falls to the inner bottom 631. This fall promotes the separation of powder adhering to the transported object 9. At this time, the transported object 9 may flip over, causing it to be turned upside down.

[0112] Furthermore, some of the transported objects 9 on inner bottom 631 move up from upstream end ED3 of unloading slope 633 along inner wall 632, and reach unloading area 639 of unloading slope 633. Some of the transported objects 9 that have reached unloading area 639 continue to move circumferentially due to vibration, reach downstream end ED4 of unloading slope 633, and drop to inner bottom 631. Meanwhile, the other parts of the transported objects 9 that have reached unloading area 639 move radially outward due to vibration.

[0113] Here, the outer edge of the discharge area 639 of the discharge slope 633 is connected to the upper end (the right end in FIG. 5) of the first chute 12 via the inner discharge opening 630 and the outer discharge opening 620. Meanwhile, the lower end (the left end in FIG. 5) of the first chute 12 is connected to the supply conveyor 13 as shown in FIG. 1. As a result, the transported object 9 that has moved radially outward in the discharge area 639 is discharged to the first chute 12.

[0114] As shown in Fig. 5, lid 64 covers the upper parts of outer bowl portion 62 and inner bowl portion 63. As shown in Figs. 5 and 10, lid 64 is provided with a through-hole 648 into which sleeve 701 of feeding mechanism 700 (Fig. 5) is inserted. Also as shown in Figs. 5 and 10, lid 64 has a plurality of nozzles 641. Nozzles 641 are gas supply ports that blow gas from above lid 64 toward below lid 64.

[0115] As shown in Fig. 5, suction mechanism 65 is a mechanism for sucking powder from inside bowl feeder 11. Suction mechanism 65 has individual suction pipes 651, collective suction pipes 652, a powder recovery unit 653, and an exhaust pump 654. In Fig. 5, pipes 651 and 652 are conceptually shown by dashed lines.

[0116] The upstream end of each individual suction pipe 651 is connected to the lower discharge port 623 or the side discharge port 624 of the outer bowl portion 62. The downstream end of each individual suction pipe 651 is connected to the upstream end of a collective suction pipe 652. A powder recovery section 653 and an exhaust pump 654 are inserted in the collective suction pipe 652.

[0117] The gas supply mechanism 66 is a mechanism for blowing gas from the upper part of the inner bowl portion 63 via a nozzle 641 toward the transported object 9 placed inside the inner bowl portion 63. The gas supply mechanism 66 has an individual gas supply pipe 661, a collective gas supply pipe 662, and an gas supply pump 663. In FIG. 5, the pipes 661 and 662 are conceptually shown by dashed lines.

[0118] The downstream end of each of the individual air supply pipes 661 is connected to the outer (upper) end of a nozzle 641 provided on the lid 64. The upstream end of each of the individual air supply pipes 661 is connected to the downstream end of a collective air supply pipe 662. An air supply pump 663 is inserted in the collective air supply pipe 662.

[0119] When the bowl feeder 11 is driven, the outer bowl portion 62 and the inner bowl portion 63 vibrate, and the suction mechanism 65 sucks in the gas inside the outer bowl portion 62, and the gas supply mechanism 66 blows gas onto the top surface of the inner bowl portion 63.

[0120] Due to the vibration of inner bowl portion 63 and the contact between the objects 9 due to the vibration, powder adhering to the objects 9 in inner bowl portion 63 detaches from the surface of the objects 9. At this time, gas supply mechanism 66 generates an airflow from above to below within inner bowl portion 63. This encourages the powder that has detached from the surface of the objects 9 to move downward without re-adhering to the surface of the objects 9. The powder that has detached from the objects 9 on inner bottom portion 631 falls downward through through-holes 90 in inner bottom portion 631 (FIG. 11) and heads toward the space between inner bottom portion 631 of inner bowl portion 63 and outer bottom portion 621 of outer bowl portion 62 (see FIG. 5). In addition, powder that separates from the transported object 9 on the discharge slope 633 and the fall slope 634 falls downward through the through holes in the discharge slope 633 and the fall slope 634, and then falls downward through the through hole 90 in the inner bottom 631 of the inner bowl portion 63, heading toward the above-mentioned space.

[0121] The space is communicated with the outside by lower discharge port 623. In addition, as shown in Figures 6 and 7, the lower end of inner bottom portion 631 is disposed between the upper and lower ends of side discharge port 624. As a result, the upper portion of side discharge port 624 communicates the space between outer wall portion 622 and inner wall portion 632 with the outside, and the lower portion of side discharge port 624 communicates the space between outer bottom portion 621 and inner bottom portion 631 with the outside.

[0122] Therefore, the powder that has fallen into the space is discharged from lower discharge port 623 and side discharge port 624 by suction using suction mechanism 65. In addition, powder that is blown up and heads toward the space between outer wall portion 622 and inner wall portion 632 is also discharged from side discharge port 624.

[0123] 9, four lower discharge ports 623 are arranged at equal intervals in the circumferential direction of outer bowl portion 62, and four side discharge ports 624 are arranged at equal intervals in the circumferential direction of outer bowl portion 62. Furthermore, the four lower discharge ports 623 and the four side discharge ports 624 are arranged alternately at equal intervals in the circumferential direction of outer bowl portion 62. This allows powder that has fallen into the space between outer bowl portion 62 and inner bowl portion 63 to be efficiently discharged through discharge ports 623, 624.

[0124] 10, the eight nozzles 641 are arranged at equal intervals in the circumferential direction, with four sets of nozzles 641, each set consisting of two nozzles 641 aligned radially. The four radially inner nozzles 641 can blow gas toward the transported objects 9 on the inner bottom 631, inside the discharge slope 633 and the drop slope 634. The four radially outer nozzles 641 can blow gas toward the transported objects 9 on the discharge slope 633 and the drop slope 634.

[0125] In this manner, in bowl feeder 11, by arranging through holes 90 over the entire area of ​​inner bottom 631 of inner bowl portion 63, powder that has separated from conveyed object 9 can be allowed to fall below inner bottom 631 without remaining on inner bottom 631, regardless of the position of conveyed object 9 on inner bottom 631. This improves the efficiency of removing powder from conveyed object 9 and also makes it possible to prevent powder from re-adhering to conveyed object 9.

[0126] Furthermore, the downstream end ED4 of the discharge slope 633 and the downstream end ED2 of the drop slope 634 each form a step from the inner bottom 631, causing the transported object 9 to fall over the step. The impact of the fall makes it easier for powder adhering to the surface of the transported object 9 to come off, and the transported object 9 may be turned over. By turning the transported object 9 over, the impact of vibrations and the blowing of gas by the gas supply mechanism 66 can be applied more evenly to the surface of the transported object 9. This allows powder to be removed from both the front and back of the transported object 9.

[0127] Furthermore, by providing through holes throughout the entire area of ​​discharge slope 633 and fall slope 634, powder that has fallen from conveyed object 9 on discharge slope 633 and fall slope 634 can fall below slopes 633 and 634 without remaining on slopes 633 and 634. This improves the efficiency of removing powder from conveyed object 9 on slopes 633 and 634 as well, and also makes it possible to prevent powder from re-adhering to conveyed object 9.

[0128] Furthermore, by blowing gas downward from nozzle 641 provided on lid 64 above inner bowl portion 63, an airflow from above to below is supplied to transported object 9 inside inner bowl portion 63. This prevents powder that has separated from the surface of transported object 9 from flying up, and encourages the powder to move downward in inner bowl portion 63. Therefore, it is possible to prevent powder from re-adhering to transported object 9.

[0129] <Embodiment 2> FIG. 17 is a top view showing the configuration of bowl feeder 11 in the second embodiment from the same perspective as FIG. 8 (first embodiment). In the second embodiment, discharge guard section 59 is provided instead of discharge slope 633 in the first embodiment (FIG. 8). Discharge guard section 59 is a member for preventing conveyed objects 9 other than the conveyed objects 9 that have fallen from downstream end ED2 of drop slope 634 from being conveyed out. Discharge guard section 59 is disposed along a position corresponding to the inner edge of discharge slope 633 (FIG. 8: first embodiment). Specifically, the portion of inner bottom section 631 between discharge guard section 59 and inner bowl section 63 is guarded area 633V corresponding to discharge slope 633 (FIG. 8). The portion of guarded area 633V corresponding to discharge area 639 (FIG. 8) is discharge area 639V. In the present embodiment, first chute 12 is connected to discharge area 639V, which is a part of inner bottom section 631.

[0130] The discharge guard portion 59 is disposed on the bottom surface BS2 of the inner bowl portion 63. The discharge guard portion 59 may be detachably attached to the inner bowl portion 63. Specifically, the discharge guard portion 59 may be attached to the inner bowl portion 63 by a fastening member. The fastening member is, for example, a screw. The thickness dimension of the discharge guard portion 59 (specifically, the maximum dimension in the z direction) is preferably at least half the thickness dimension of the transported object 9. The thickness dimension of the discharge guard portion 59 may be smaller than the height dimension of the inner wall portion 632 of the inner bowl portion.

[0131] Note that the configuration other than the above is substantially the same as the configuration of the first embodiment described above, and therefore the same or corresponding elements are given the same reference numerals and description thereof will not be repeated.

[0132] <Third Embodiment> In this third embodiment, a specific configuration of sleeve 701 (FIG. 5) of bowl feeder 11 will be described. FIG. 18 is a bottom view showing the configuration of sleeve 701 of the feeding section in the third embodiment. FIG. 19 is a partial cross-sectional view of sleeve 701 and inner bottom portion 631 of inner bowl portion 63 (see FIG. 5) in a view taken along line XIX-XIX in FIG. 18.

[0133] The lower end PE of the sleeve 701 has an effective portion PE1 and an ineffective portion PE2. A gap dimension GS1 between the effective portion PE1 and the bottom surface BS2 of the inner bowl portion 63 is larger than the thickness of the load 9. A gap dimension GS2 between the ineffective portion PE2 and the bottom surface BS2 of the inner bowl portion 63 is smaller than the thickness of the load 9, and preferably smaller than half the thickness of the load 9.

[0134] In the planar layout, a straight line LS (FIG. 18) extending from the center CT (FIG. 18) of the central region RC of the bottom surface BS2 of the inner bowl portion 63 to the upstream end EUS (FIGS. 8 and 18) of the volute guide portion 81 overlaps with the invalid portion PE2 of the lower end portion PE of the sleeve 701. In the example shown in FIG. 18, the straight line LS overlaps with the boundary between the effective portion PE1 and the invalid portion PE2 in the planar layout, and in such a case, the straight line LS is also considered to overlap with the invalid portion PE2. As a variant, the lower end portion PE may be configured so that the straight line LS is separated from the effective portion PE1.

[0135] According to this embodiment, gap dimension GS1 is larger than the thickness of transported object 9, and gap dimension GS2 is smaller than the thickness of transported object 9. This makes it easier for transported object 9 to be introduced from effective portion PE1 rather than from ineffective portion PE2. Therefore, transported object 9 can be selectively introduced from sleeve 701 into a specific angle range in the planar layout.

[0136] Furthermore, in the planar layout, the straight line LS extending from the center CT of the central region RC of the bottom surface BS2 of the inner bowl portion 63 to the upstream end of the spiral guide portion 81 overlaps the invalid portion PE2 of the lower end PE of the sleeve 701. This makes it difficult for the conveyed object 9 introduced from the central region RC to move toward the upstream end EUS of the spiral guide portion 81. This prevents the conveyed object 9 from accumulating near the end EUS. This effect is further enhanced by configuring the lower end PE so that the straight line LS is separated from the valid portion PE1. On the other hand, if the proportion of the valid portion PE1 around the center CT is too small, the conveyed object 9 is difficult to introduce. From the perspective of ensuring a good balance between these two, a configuration in which the straight line LS overlaps the boundary between the valid portion PE1 and the invalid portion PE2 in the planar layout, as shown in FIG. 18, is a preferred example.

[0137] The configuration other than the above is substantially the same as that of the first or second embodiment, and therefore the same or corresponding elements are denoted by the same reference numerals and will not be described again. If the effect of this embodiment is not particularly required, it is not necessary to provide the invalid portion PE2 at the lower end portion PE.

[0138] <Fourth Embodiment> Figure 20 is a partial cross-sectional view schematically showing the configuration of inner bowl section 63 in embodiment 4. In embodiment 4, inner bottom 631 of inner bowl section 63 of bowl feeder 11 has bottom surface BS2V instead of the substantially flat bottom surface BS2 (Figure 5: embodiment 1).

[0139] The outer peripheral region RO of the bottom surface BS2V of the inner bowl portion 63 is gradually lowered as it moves away from the central region RC. Furthermore, the central region RC may be gradually lowered as it moves away from the center CT. In the example shown in FIG. 20, the bottom surface BS2V forms a side surface of a cone with the center CT as its apex. In this case, the bottom surface BS2V is gradually lowered as it moves away from the center CT.

[0140] Corresponding to the above-described configuration of the bottom surface BS2V, the surface of the drop slope 634 may also be lowered as it moves away from the central region RC. The surface may also be lowered as it moves away from the center CT. Similarly, the surface of the unloading slope 633 may also be lowered as it moves away from the central region RC. The surface may also be lowered as it moves away from the center CT.

[0141] The configuration other than the above is substantially the same as that of any one of the first to third embodiments described above, and therefore the same or corresponding elements are designated by the same reference numerals and description thereof will not be repeated.

[0142] According to this embodiment, it is possible to promote the outward movement of the load 9 on the bottom surface BS2V. The inclination angle formed by lowering the bottom surface BS2V as it moves away from the central region RC is selected so as to sufficiently obtain this effect.

[0143] <Fifth Embodiment> FIG. 21 is a top view of bowl feeder 11 according to the fifth embodiment, with lid 64 and feeding mechanism 700 (see FIG. 5) omitted. In the fifth embodiment, bowl feeder 11 has a plurality of guide sections 82 instead of spiral guide section 81 (FIG. 8: first embodiment). The plurality of guide sections 82 includes guide sections 82a to 82g. Guide sections 82a to 82g are arranged in this order approximately along a spiral that winds outward in a circumferential direction (clockwise in the example shown in FIG. 21) when viewed from above. The plurality of guide sections 82 define a transport path PS for transported objects 9 on bottom surface BS2 of inner bowl section 63. In a planar layout, transport path PS includes a spiral path that extends along a spiral that winds outward in a circumferential direction (clockwise in the example shown in FIG. 21) when viewed from above.

[0144] Each of the multiple guide portions 82 has an inner surface facing the central region RC in the planar layout and an outer surface opposite the inner surface. The multiple guide portions 82 include a guide portion 82a (first guide portion) and a guide portion 82b (second guide portion) that are adjacent to each other in a line-up along the conveying path PS. The line-up from the guide portion 82a to the guide portion 82b corresponds to the upstream-to-downstream direction of the conveying path PS. A portion of the outer surface of the guide portion 82a and a portion of the inner surface of the guide portion 82b face each other. A gap dimension between a portion of the outer surface of the guide portion 82a and a portion of the inner surface of the guide portion 82b may be less than the thickness dimension of the conveyed object 9. Furthermore, the gap dimension may be less than half the thickness dimension of the conveyed object 9.

[0145] The relationship between guide portion 82a and guide portion 82b has been explained above, but the same applies to the relationship between guide portion 82b and guide portion 82c, the relationship between guide portion 82c and guide portion 82d, the relationship between guide portion 82d and guide portion 82e, the relationship between guide portion 82e and guide portion 82f, and the relationship between guide portion 82f and guide portion 82g.

[0146] The guide portion 82 is disposed on the bottom surface BS2 of the inner bowl portion 63. The guide portion 82 may be detachably attached to the inner bowl portion 63. Specifically, the guide portion 82 may be attached to the inner bowl portion 63 by a fastening member. The fastening member is, for example, a screw.

[0147] In the planar layout, an extension line LG of a straight line extending from the center CT of the central region RC of the bottom surface BS2 of the inner bowl portion 63 toward the downstream end EDS of the multiple guide portions 82 may overlap with the drop slope 634.

[0148] The thickness dimension of the multiple guide portions 82 (specifically, the maximum dimension in the z direction) is preferably at least half the thickness dimension of the transported object 9. The thickness dimension of the multiple guide portions 82 may be smaller than the height dimension of the inner wall portion 632 of the inner bowl portion.

[0149] In the fifth embodiment, the transport path PS includes a spiral path in the planar layout, as in the first to fourth embodiments. In the present embodiment, such a transport path PS can be defined by a plurality of guide portions .

[0150] A part of the outer surface of guide portion 82a and a part of the inner surface of guide portion 82b may face each other, thereby allowing the flow of conveyed object 9 to smoothly transition from a path along the inner surface of guide portion 82a to a path along the inner surface of guide portion 82b.

[0151] The gap dimension between a portion of the outer surface of guide portion 82a and a portion of the inner surface of guide portion 82b may be less than the thickness dimension of transported object 9. This makes it difficult for transported object 9 to enter between the portion of the outer surface of guide portion 82a and the portion of the inner surface of guide portion 82b. To further enhance this effect, the gap dimension is preferably less than half the thickness dimension of transported object 9.

[0152] The guide portion 82 may be detachably attached to the inner bowl portion 63. This allows the guide portion 82 to be removed when performing maintenance on the bowl feeder 11.

[0153] In the planar layout, an extension line LG of a straight line extending from the center CT of the central region RC of the bottom surface BS2 of the inner bowl portion 63 toward the downstream end EDS of the plurality of guide portions 82 overlaps with the drop slope 634. This makes it easier to reliably transport the transported object 9 from the downstream of the transport path PS defined by the plurality of guide portions 82 onto the drop slope 634.

[0154] It should be noted that, within the scope of not causing any contradiction, it is possible to freely combine the respective embodiments, and to appropriately modify or omit the respective embodiments. [Explanation of symbols]

[0155] 1: Tablet printing equipment 9, 9A, 9B: Transported object (tablets) 11: Bowl feeder (vibration feeder) 12: First shot 62: Outer bowl section (first bowl section) 63: Inner bowl section (second bowl section) 64: Lid 68: Oscillator 81: Spiral guide section (guide section) 82, 82a~82g: Guide section 90: Through hole 633: Loading ramp 633V: Guarded area 634: Falling Slope 639,639V: Export area 700: Feeding mechanism 701: Sleeve (insertion part) BS1: Bottom (1st bottom) BS2, BS2V: Bottom (second bottom) CT: Center PE: Bottom end PE1: valid part PE2: Invalid part PS: Transport Route RC: Central region

Claims

1. 1. A vibrating feeder that conveys a thickness-dimensioned object from upstream to downstream while removing powder adhering to the object from the object, comprising: a first bowl portion having a first bottom surface and a bowl opening above the first bottom surface, the first bowl portion being provided with a first outlet for discharging the transported object from the vibrating feeder; a second bowl portion disposed inside the first bowl portion, the second bowl portion having a second bottom surface with a plurality of through holes having a size that allows the powder to pass while preventing the object from passing through, and a bowl opening above the second bottom surface, the second bottom surface of the second bowl portion having a central region and an outer circumferential region around the central region, and a second discharge outlet is provided in the second bowl portion between the outer circumferential region and the first discharge outlet, and the vibratory feeder further comprises: an input section for inputting the object onto the central region of the second bottom surface of the second bowl section; a vibrator that vibrates the second bowl portion to move the transported object outward on the second bottom surface of the second bowl portion from the central region through the outer circumferential region to the second outlet; at least one guide portion arranged on the second bottom surface of the second bowl portion for guiding the transported object so that the transported object moves in a circular direction that is either a clockwise direction or a counterclockwise direction in conjunction with the outward movement of the transported object.

2. The vibratory feeder according to claim 1 , wherein the at least one guide portion includes a spiral guide portion that extends along a spiral that winds outward in the circumferential direction in a planar layout.

3. 3. The vibrating feeder according to claim 2, wherein the spiral guide portion is wound 360 degrees or more.

4. 2. The vibrating feeder of claim 1, wherein the at least one guide portion is a plurality of guide portions that define a transport path for the transported object on the second bottom surface of the second bowl portion, and the transport path includes, in a planar layout, a spiral path that extends along a spiral that winds outward in the circumferential direction.

5. 5. The vibrating feeder of claim 4, wherein each of the plurality of guide portions has an inner surface facing the central region in a planar layout and an outer surface opposite the inner surface, the plurality of guide portions include a first guide portion and a second guide portion adjacent to each other in a line-up along the conveying path, the line-up from the first guide portion to the second guide portion corresponds to the direction from the upstream to the downstream, and a portion of the outer surface of the first guide portion and a portion of the inner surface of the second guide portion face each other.

6. 6. The vibrating feeder according to claim 5, wherein a gap dimension between the part of the outer surface of the first guide portion and the part of the inner surface of the second guide portion is less than the thickness dimension of the transported object.

7. 7. The vibratory feeder of claim 1, wherein the at least one guide portion is removably attached to the second bowl portion.

8. 7. The vibratory feeder of claim 1, further comprising a fall slope arranged on the outer circumferential region of the second bottom surface of the second bowl portion, the fall slope having a first end for causing the transported object to climb up and a second end for causing the transported object that has climbed up onto the fall slope at the first end to fall onto the second bottom surface of the second bowl portion, the second end being positioned higher from the second bottom surface of the second bowl portion than the first end.

9. 9. The vibratory feeder according to claim 8, wherein, in a planar layout, an extension of a straight line extending from the center of the central region of the second bottom surface of the second bowl portion toward the downstream end of the at least one guide portion overlaps with the drop slope.

10. 7. The vibratory feeder according to claim 1, wherein the feed section has an input opening facing the central region of the second bottom surface of the second bowl section, and a lower end portion surrounding the input opening.

11. The vibrating feeder according to claim 10 , wherein in a planar layout, a shortest distance between the lower end of the input portion and the at least one guide portion is smaller than the thickness dimension of the transported object.

12. the lower end of the input portion has an effective portion and an ineffective portion, 11. The vibrating feeder of claim 10, wherein a gap dimension between the effective portion and the second bottom surface of the second bowl portion is larger than a thickness dimension of the transported object, and a gap dimension between the ineffective portion and the second bottom surface of the second bowl portion is smaller than a thickness dimension of the transported object.

13. The vibratory feeder of claim 12, wherein in a planar layout, a straight line from the center of the central region of the second bottom surface of the second bowl portion to the upstream end of the at least one guide portion overlaps the invalid portion of the lower end of the input portion.

14. The vibratory feeder according to claim 1 , wherein the second bottom surface of the second bowl portion is gradually lowered with increasing distance from the central region.

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