Powder feeding device

Abstract

The present invention provides a powder supply device that can maintain a constant amount of powder being stirred up, regardless of the amount of powder contained in the bucket. [Solution] The powder supply device 1 that supplies powder P to the dust collector 90 includes a bucket 3 for containing the powder P, a nozzle section 4 for injecting high-pressure air into the powder P contained in the bucket 3 to blast the powder P to be supplied to the dust collector 90, and a lifting section 5 that lowers the bucket 3 as the amount of powder P contained in the bucket 3 increases and raises the bucket 3 as the amount of powder P contained in the bucket 3 decreases.

Description

Technical Field

[0001] The present invention relates to a powder supply device for supplying powder to a dust collection device.

Background Art

[0002] When a dust collector (dust collection device) collects dust, in order to suppress ignition of the dust or clogging of the filter, a powdery precoat agent (precoat agent) may be attached to the filter of the dust collector to form a precoat layer (precoat layer). There is known a precoat charging device that charges a precoat agent into a dust collector and forms a precoat layer on the filter (Patent Document 1). The precoat charging device has a hopper for storing the precoat agent, a connection duct for charging the precoat agent in the hopper into the dust collector, and a nozzle for blowing high-pressure air (compressed air) into the hopper. The nozzle has flexibility, and the tip of the nozzle (the outlet of the high-pressure air) is buried in the precoat agent stored in the hopper.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the pre-coat dispensing device described above, when the amount of pre-coat agent stored in the hopper is large, the tip of the nozzle is embedded in the pre-coat agent. However, as the amount of pre-coat agent dispensed into the dust collector decreases, the tip of the nozzle becomes either close to the surface of the pre-coat agent or exposed from the pre-coat agent. For example, comparing the amount of pre-coat agent that is stirred up when the nozzle tip is near the surface of the pre-coat agent versus when it is located further down from the surface, the former case results in a larger amount of pre-coat agent being stirred up. Thus, in the pre-coat dispensing device described above, as the amount of pre-coat agent dispensed into the dust collector increases, the distance between the nozzle tip and the pre-coat agent (surface) changes, resulting in the problem that the amount of pre-coat agent stirred up by the high-pressure air sprayed from the nozzle is not constant.

[0005] In consideration of the above circumstances, the present invention provides a powder supply device that can keep the amount of powder that is stirred up constant, regardless of the amount of powder contained in the bucket. [Means for solving the problem]

[0006] The first powder supply device according to the present invention is a powder supply device for supplying powder to a dust collector, comprising: a bucket for containing the powder; a nozzle section for injecting high-pressure air into the powder contained in the bucket to blast the powder to be supplied to the dust collector; and a lifting section for lowering the bucket as the amount of powder contained in the bucket increases and raising the bucket as the amount of powder contained in the bucket decreases.

[0007] According to the first powder supply device of the present invention, the lifting unit raises and lowers the bucket in accordance with the increase or decrease in the amount of powder contained, so that the distance between the tip of the nozzle (high-pressure air injection port) and the surface (top surface) of the powder can be kept approximately constant. As a result, the amount of powder that is stirred up by the high-pressure air injected from the nozzle can be kept constant, regardless of the amount of powder contained in the bucket. As a result, the amount of powder supplied to the dust collector can be kept constant. In this specification, "constant" does not mean that it is completely fixed and does not move, but rather that slight fluctuations are permitted.

[0008] The second powder supply device of the present invention is the first powder supply device of the present invention described above, wherein the lifting section has an elastic member that contacts the lower surface of the bucket and biases the bucket upward.

[0009] According to the second powder supply device of the present invention, the bucket can be raised and lowered by balancing the combined weight of the bucket and powder with the biasing force of the elastic member. This allows the lifting mechanism to be constructed simply and at low cost compared to cases where a drive source such as a motor or a power transmission mechanism such as gears is used to raise and lower the bucket.

[0010] The third powder supply device of the present invention is the first powder supply device of the present invention described above, wherein the lifting section is provided in an upright position, penetrates a guide section provided on the bucket, and has a plurality of guide columns that guide the lifting and lowering of the bucket, and has a plurality of compression coil springs that are provided so as to wrap around each of the guide columns, contact the lower surface of the bucket and bias the bucket upward.

[0011] According to the third powder supply device of the present invention, the bucket can be raised and lowered in a stable position by means of multiple guide columns and multiple compression coil springs. Furthermore, since the guide columns are inserted into the hollow axial center of the compression coil springs, the compression coil springs can be expanded and contracted along the guide columns.

[0012] The fourth powder supply device of the present invention is the third powder supply device of the present invention described above, wherein the lifting section further comprises a plurality of spacers provided so as to surround the outer circumference of each of the compression coil springs, and the height of the spacers is preferably set to be longer than the contact height of the compression coil springs.

[0013] According to the fourth powder supply device of the present invention, the spacer is formed to be longer than the contact height of the compression coil spring, and the lower part of the compression coil spring is inserted into the hollow axial center of the spacer. Therefore, even if the bucket is pushed down more than necessary or more powder than necessary is put into the bucket, for example, the upper end of the spacer interferes with the bucket, and the downward movement of the bucket can be restricted. As a result, the spacer functions as a stopper that restricts the downward movement of the bucket, and damage to the compression coil spring, such as buckling due to compression to the contact height, can be suppressed.

[0014] The fifth powder supply device of the present invention may further include, in the first to fourth powder supply devices of the present invention described above, a case for housing the bucket and the lifting unit, and a plurality of container support units provided between the case and the bucket, spaced apart in a direction circumferential to the outer surface of the bucket, and supporting the bucket so that it can be raised and lowered.

[0015] According to the fifth powder supply device of the present invention, since multiple container support parts are provided at intervals in the circumferential direction between the case and the bucket, the bucket can be raised and lowered while maintaining a stable posture.

[0016] The sixth powder supply device of the present invention is the fifth powder supply device of the present invention described above, wherein each container support portion preferably includes a roller that contacts the outer surface of the bucket and rotates around an axis as the bucket is raised and lowered, and a support biasing plate that rotatably supports the roller, is fixed to the case, and presses the roller against the outer surface of the bucket.

[0017] According to the sixth powder supply device of the present invention, the roller is biased by the support biasing plate and contacts the outer surface of the bucket, and rotates as the bucket is raised and lowered, thus enabling smooth and stable raising and lowering of the bucket. Furthermore, since the support biasing plate has the function of pivotally supporting the roller and the function of pressing the roller against the outer surface of the bucket, the number of parts can be reduced compared to when both functions are realized by separate parts, and the manufacturing cost of the container support can be reduced.

[0018] The seventh powder supply device of the present invention is the sixth powder supply device of the present invention described above, wherein the bucket is formed in a cylindrical shape having a bottom surface, the case is formed in a square cylindrical shape having a bottom surface, and the plurality of container support parts are arranged at the four corners when the case is viewed from a plane. Each of the aforementioned support and biasing plates is preferably installed between adjacent side plates that straddle the vertical ridge of the case, in a position that intersects the diagonal of the case.

[0019] According to the seventh powder supply device of the present invention, by housing a cylindrical bucket in a rectangular tubular case, the four dead spaces created at the four corners of the case can be effectively utilized as space for arranging multiple (four) container support parts. This eliminates the need to enlarge the case in order to arrange multiple container support parts between the case and the bucket, thereby making the powder supply device more compact.

[0020] The eighth powder supply device of the present invention is the fifth powder supply device of the present invention described above, wherein a remaining amount indicator part that indicates the amount of powder contained in the bucket is fixed to the outer surface of the bucket, and the case is formed with a remaining amount viewing part that allows the remaining amount indicator part fixed to the bucket to be seen from the outside.

[0021] According to the eighth powder supply device of the present invention, the amount of powder contained in the bucket (remaining amount) can be confirmed from outside the case by visually checking the remaining amount indicator of the bucket through the remaining amount viewing section of the case. [Effects of the Invention]

[0022] According to the present invention, regardless of the storage capacity of the powder stored in the bucket, the amount of the powder lifted can be made constant.

Brief Description of the Drawings

[0023] [Figure 1] It is a perspective view showing a powder supply device and a dust collection device according to an embodiment of the present invention. [Figure 2] It is a block diagram showing a powder supply device, a dust collection device, and a control panel according to an embodiment of the present invention. [Figure 3] It is a perspective view showing a powder supply device according to an embodiment of the present invention. [Figure 4] It is a perspective view showing a state where the lid of the powder supply device according to an embodiment of the present invention is opened. [Figure 5] It is a perspective view showing the internal structure of the powder supply device according to an embodiment of the present invention. [Figure 6] It is a cross-sectional view showing a powder supply device according to an embodiment of the present invention. [Figure 7] It is a perspective view showing a light-shielding plate, a remaining amount detection and adjustment plate, etc. of the powder supply device according to an embodiment of the present invention. [Figure 8] It is a three-view drawing and a perspective view showing a nozzle of the powder supply device according to an embodiment of the present invention. [Figure 9] It is an exploded perspective view showing a bucket and a lifting part of the powder supply device according to an embodiment of the present invention. [Figure 10] It is a plan view showing a bucket and a container support part, etc. of the powder supply device according to an embodiment of the present invention. [Figure 11] It is a perspective view showing a container support part of the powder supply device according to an embodiment of the present invention. [Figure 12] It is a side view (partial cross-sectional view) for explaining the lifting operation of the bucket of the powder supply device according to an embodiment of the present invention. [Figure 13] It is a time chart of a dust collection method by a powder supply device and a dust collection device according to an embodiment of the present invention. [Modes for carrying out the invention]

[0024] Embodiments of the present invention will be described below with reference to the attached drawings. Note that Fr, Rr, L, R, U, and D in the drawings indicate front, rear, left, right, top, and bottom. The front-to-back, left-to-right, and up-to-down directions are orthogonal to each other. While this specification uses terms to indicate direction and position, these terms are used for convenience of explanation and do not limit the technical scope of the present invention.

[0025] A powder supply device 1 according to one embodiment will be described with reference to Figures 1 to 11. Figure 1 is a perspective view showing the powder supply device 1 and the dust collector 90. Figure 2 is a block diagram showing the powder supply device 1, the dust collector 90 and the control panel 80. Figure 3 is a perspective view showing the powder supply device 1. Figure 4 is a perspective view showing the lid 11 of the powder supply device 1 in the open state. Figure 5 is a perspective view showing the internal structure of the powder supply device 1. Figure 6 is a cross-sectional view showing the powder supply device 1. Figure 7 is a perspective view showing the cover plate 34 and the remaining amount detection adjustment plate 35 of the powder supply device 1. Figure 8 is a three-view and perspective view showing the nozzles 41 and 42 of the powder supply device 1. Figure 9 is an exploded perspective view showing the bucket 3 and the lifting part 5 of the powder supply device 1. Figure 10 is a plan view showing the bucket 3 and the container support part 6 of the powder supply device 1. Figure 11 is a perspective view showing the container support part 6 of the powder supply device 1.

[0026] As shown in Figure 1, the powder supply device 1 is installed adjacent to the dust collector 90 and is configured to operate in conjunction with the dust collector 90. Before describing the powder supply device 1, the dust collector 90 will be briefly described.

[0027] [Dust collector] The dust collector 90 is, for example, a pulse-jet type dust collector that sucks in air containing dust (dust-laden air) generated from processing equipment, etc., and purifies the air in the factory where the processing equipment, etc. is installed. The dust collector 90 has a dust collection main body 91 which is a roughly rectangular parallelepiped shape that is long in the vertical direction. A suction pipe 92 is attached to the upper rear of the left side of the dust collection main body 91, and a damper 92A is provided in the suction pipe 92 to open and close the flow path of dust-laden air. An exhaust port 93 is formed on the top surface of the dust collection main body 91.

[0028] The dust collection unit 91 is divided into a dust collection chamber and a cleaning chamber by a partition plate (neither of which are shown). The dust collection chamber is provided with multiple rectifier plates (not shown) and multiple filters (not shown), while the cleaning chamber is provided with a suction fan 94 (see Figure 2), etc. The filters have a filter material (for example, a nonwoven fabric formed in a pleated shape) that collects dust. The dust collection unit 91 is also provided with a dust removal device 95 (see Figure 2) that sprays compressed air (pulse jet) towards the filters to remove the dust collected on the filters (filter material). The dust removal device 95 includes a solenoid valve (not shown) that controls the injection of compressed air. The dust collection unit 91 is also provided with a rotation speed measuring unit 96 for measuring the rotation speed of the suction fan 94 and a differential pressure measuring unit 97 (see Figure 2) for measuring the differential pressure of the filters.

[0029] When the dust collector 90 (suction fan 94) is in operation, air containing dust generated from the processing equipment (dust-laden air) is drawn into the dust collection chamber through the suction pipe 92 and flows towards multiple filters via multiple rectifier plates. As the dust-laden air passes through the filters, the dust is collected by the filter media. The clean air, from which the dust has been removed, is exhausted to the outside of the dust collector 90 through the exhaust port 93 after passing through the clean chamber. When the processing equipment stops (when the suction of dust-laden air ends), the dust removal device 95 of the dust collector 90 blows compressed air onto the filters to remove the dust collected on the filters (filter media) (backwashing or filter cleaning of the filters).

[0030] [Powder feeding device] As shown in Figure 1, the powder supply device 1 is connected to the suction pipe 92 of the dust collector 90 via the powder discharge hose 26. The powder supply device 1 supplies powder P (pre-coating agent) to the dust collector 90, and the powder P adheres to the filter (filter material) to form a pre-coating layer. By forming a pre-coating layer on the filter, ignition of dust sucked into the dust collector 90 is suppressed, and clogging of the filter is suppressed. The pre-coating layer is particularly effective when sucking up and collecting easily ignitable dust or sticky (adherent) dust.

[0031] The powder supply device 1 comprises a case 2, a bucket 3, a nozzle section 4, a lifting section 5, and four container support sections 6 (see also Figure 5).

[0032] <Case> As shown in Figure 3, Case 2 constitutes the main exterior of the powder supply device 1. As shown in Figures 3 to 6, Case 2 has a case body 10, a lid 11, and an inner cylinder 12.

[0033] (Case body) The case body 10 is formed in a rectangular cylindrical shape with a bottom surface. A circular case opening 10A (see Figure 4) is provided on the top surface of the case body 10. A hinge portion 13 is provided at the upper end of the left side of the case body 10, and clamp portions 14 are provided at the upper end of the right side, the upper end of the front side, and the upper end of the rear side of the case body 10.

[0034] As shown in Figures 3 to 5, a remaining amount viewing section 15 is formed near the center of the front side of the case body 10, allowing the remaining amount indicator section 31 (described later), which is fixed to the bucket 3, to be seen from the outside. The remaining amount viewing section 15 includes an opening formed in a part of the front side of the case body 10 and a transparent acrylic plate that covers this opening. A horizontal reference line 15A is printed on the acrylic plate. As will be described in detail later, the worker can see the remaining amount indicator section 31 of the bucket 3 through the remaining amount viewing section 15 from the outside and determine the remaining amount of powder P in the bucket 3.

[0035] As shown in Figures 1, 3 through 6, a regulator 16 is mounted on the left side of the front surface of the case body 10. The regulator 16 is connected to the factory's compressed air equipment (not shown) via a first air hose 21 (see Figure 1). The compressed air equipment supplies high-pressure air (compressed air) of, for example, 0.7 to 1.0 MPa to the regulator 16, and the regulator 16 adjusts the supplied high-pressure air to a pressure of, for example, 0.4 to 0.6 MPa. A header tank 17 (see Figures 5 and 6) is located inside the case body 10 (on the bottom surface), and the regulator 16 is connected to the header tank 17 via a second air hose 22 (see Figure 1). The regulator 16 supplies the pressure-adjusted high-pressure air to the header tank 17, and the header tank 17 stores the supplied high-pressure air. The capacity of the header tank 17 is, for example, several liters to several tens of liters. When the high-pressure air is consumed (the amount stored decreases), high-pressure air is replenished in the header tank 17.

[0036] As shown in Figures 3 and 4, an operating section 18, operated by an operator, is provided at the right end of the front side of the case body 10. The operating section 18 includes various switches (manual / interlocking switch, power switch) and various buttons (operation button, stop button), as well as various lamps (power indicator lamp, operation lamp), etc., which are operated by the operator.

[0037] As shown in Figures 3 and 4, a control panel 80 for controlling the powder supply device 1 and the dust collector 90 is provided on the front side of the case body 10. As shown in Figure 2, the control panel 80 is configured by connecting a processing unit 81, a storage device 82, and an interface 83 via a bus 84. The processing unit 81 includes a CPU (central processing unit), and the storage device 82 includes RAM (random access memory) and ROM (read-only memory). Various control targets are connected to the interface 83 so that they can send and receive electrical signals. The regulator 16 and the operating unit 18 are electrically connected to the interface 83 and controlled as appropriate by the control panel 80. In addition, the suction fan 94, dust removal device 95, rotation speed measuring unit 96, and differential pressure measuring unit 97 of the dust collector 90 are also electrically connected to the interface 83 and controlled as appropriate by the control panel 80. The powder supply device 1, the dust collector 90, and the control panel 80 are connected to each other via a signal line 85 (see Figure 1). Furthermore, power cables 86 for supplying power are connected to the powder supply device 1, the dust collector 90, and the control panel 80 (see Figure 1).

[0038] (Lid) As shown in Figures 3 and 4, the lid 11 is formed in a generally disc shape and is provided so as to be able to close the case opening 10A of the case body 10 (more specifically, the upper end opening of the inner cylinder 12, which will be described later). The lid 11 is rotatably supported on the case body 10 via a hinge 13. A discharge pipe 25 is provided at a position offset radially outward from the center of the lid 11. The discharge pipe 25 is formed in a substantially cylindrical shape and is fixed to the lid 11 in a state where it penetrates the lid 11 in the thickness direction (vertical direction). The upstream end of the powder discharge hose 26 is connected to the downstream side of the discharge pipe 25 (the portion exposed upward from the lid 11) (see Figure 1). The powder discharge hose 26 extends upward from the discharge pipe 25, and the downstream end of the powder discharge hose 26 is connected to the suction pipe 92 of the dust collector 90 (see Figure 1). In this specification, the lid 11 will be described in principle in the closed state.

[0039] The upper surface of the lid 11 is provided with three fastening parts 27 and one clamping rod 28. Each fastening part 27 is formed in a roughly U-shape, projecting radially outward from the outer edge of the lid 11 when viewed from above. The three fastening parts 27 are positioned at 90-degree angles in the circumferential direction so as to engage with the three clamping parts 14 of the case 2 when viewed from above. When the lid 11 is closed, each fastening part 27 engages with the clamping parts 14, holding the lid 11 in a closed position. The clamping rod 28 is formed in a roughly U-shape, projecting from the upper surface of the lid 11 near the hinge part 13. When the lid 11 is opened, the clamping rod 28 engages with the hinge part 13, holding the lid 11 in an open position.

[0040] (Inner cylinder section) As shown in Figures 4 and 6, the inner cylinder portion 12 is formed in a generally cylindrical shape, positioned on the upper side inside the case body 10, and fixed to the four sides of the case body 10. The upper edge of the inner cylinder portion 12 is located inside the case opening 10A of the case body 10, and a packing 12A that tightly seals against the lid portion 11 is attached to the upper edge of the inner cylinder portion 12.

[0041] <bucket> As shown in Figures 5 and 6, the bucket 3 is formed in a cylindrical shape with a bottom and is housed in the case 2 (case body 10). The upper end surface of the bucket 3 is open, and an annular reinforcing plate 30 (see Figure 6) is fixed to the upper edge of the bucket 3. The reinforcing plate 30 reinforces the upper edge of the bucket 3 and maintains the cylindrical shape of the bucket 3. A space is provided between the lower surface of the bucket 3 and the bottom surface of the case body 10 for arranging the header tank 17 and the lifting unit 5 (see Figure 6).

[0042] As shown in Figure 6, the bucket 3 contains powder P for forming a pre-coat layer on the filter. For example, the powder P is packed in a polyethylene storage bag PB. The worker opens the lid 11 to open the case opening 10A, and then places the storage bag PB containing the powder P into the bucket 3. The powder P (pre-coat agent) is non-flammable, and specifically, calcium hydroxide (slaked lime), calcium carbonate (limestone), or hydrated magnesium silicate (talc) may be used. The powder P may also be poured directly into the bucket 3 instead of being packed in the storage bag PB. In this case, the gap between the bucket 3 and the inner cylinder 12 may be filled with a sealing member (not shown), such as an O-ring. This helps to suppress leakage of the powder P.

[0043] With the bucket 3 housed in the case body 10, a gap is formed between the outer surface of the bucket 3 and the inner surface of the case body 10 (see Figure 6). As shown in Figure 5, a remaining amount indicator 31, which indicates the amount of powder P contained in the bucket 3, is fixed to the outer surface of the bucket 3. The remaining amount indicator 31 is formed in a flat plate shape and is positioned opposite the remaining amount viewing section 15 of the case body 10. The remaining amount indicator 31 has a right-angled triangle representing the amount of powder P contained (remaining amount), an "F" indicating that the powder P is full, and an "E" indicating that the powder P is empty (almost empty) printed on it. Instead of the design and letters on the remaining amount indicator 31, for example, a scale may be printed (not shown). Also, a scale or the like indicating the amount of powder P contained may be formed on the inner surface of the bucket 3 (not shown).

[0044] Furthermore, as shown in Figure 5, a remaining amount detection sensor 32 (for example, a transmissive photosensor) is provided on the outer circumferential surface of the bucket 3 via a sensor fixing plate 33. The sensor fixing plate 33 is attached to the outer circumferential surface of the bucket 3 at a position facing the right side of the case body 10 when the bucket 3 is housed in the case body 10. In Figure 5, the remaining amount detection sensor 32 is attached to the upper part of the sensor fixing plate 33, but the remaining amount detection sensor 32 is attached to the sensor fixing plate 33 so that its mounting position in the vertical direction can be changed. The remaining amount detection sensor 32 detects when the bucket P is full when attached to the upper part of the sensor fixing plate 33, and detects when the bucket P is empty when attached to the lower part of the sensor fixing plate 33. The remaining amount detection sensor 32 is electrically connected to the interface 83 (see Figure 2).

[0045] As shown in Figures 3 to 5, an opening is formed on the right side of the case body 10 at a position corresponding to the remaining charge detection sensor 32, and a cover plate 34 is attached to close the opening. As shown in Figure 7, a roughly L-shaped fixing plate 34A is fixed to the back of the cover plate 34, and a remaining charge detection adjustment plate 35 is attached to the fixing plate 34A. An elongated hole 35A extending in the vertical direction is formed in the remaining charge detection adjustment plate 35, and the remaining charge detection adjustment plate 35 is attached to the fixing plate 34A by fixing bolts 35B passing through the elongated hole 35A. The remaining charge detection adjustment plate 35 is provided so that its vertical position can be adjusted (changed) within the range of the elongated hole 35A. In addition, a detection part 35C is formed in the remaining charge detection adjustment plate 35 that can enter the space (optical path) between the light-emitting part and the light-receiving part of the remaining charge detection sensor 32.

[0046] As shown in Figures 5 and 6, a pair of guide legs 36 (guide sections) are fixed to the lower surface of the bucket 3. The pair of guide legs 36 are spaced apart in the left-right direction and extend in the front-rear direction parallel to each other. Each guide leg 36 is formed in a roughly U-shape, and both ends of each guide leg 36 extend beyond the outer circumferential surface of the bucket 3. Through holes 37 are opened at both ends of the horizontal plate of each guide leg 36 (see Figure 9).

[0047] <Nozzle section> As shown in Figures 4 to 6, the nozzle section 4 includes a rotary joint 40, a pair of spray nozzles 41, and a rotating nozzle 42. Since the pair of spray nozzles 41 have the same structure, this specification will mainly focus on describing one of the spray nozzles 41. In this specification, when describing the spray nozzle 41 and the rotating nozzle 42 in common, they will simply be referred to as "nozzles 41, 42."

[0048] (Rotating joint) The rotary joint 40 is attached to the lid 11 via a joint fixing plate 44 at approximately the center of the lid 11 (see also Figure 3, etc.). The rotary joint 40 is formed in a substantially cylindrical shape that extends in the vertical direction and penetrates the lid 11 in the thickness direction (vertical direction). The rotary joint 40 is provided so as to be rotatable about an axis relative to the lid 11. The rotary joint 40 is connected to the header tank 17 via a third air hose 23 (see Figure 1). In detail, the header tank 17 is provided with an on-off valve 20 (solenoid valve), and the upstream end of the third air hose 23 is connected to the header tank 17 via the on-off valve 20. The downstream end of the third air hose 23 is connected to the side surface of the rotary joint 40 on the upstream side (the part exposed above the lid 11). The on-off valve 20 is electrically connected to an interface 83 and controlled as appropriate by a control panel 80 (see Figure 2).

[0049] (Spray nozzle, rotating nozzle) Nozzles 41 and 42 are connected to the downstream side of the rotary joint 40 (the portion extending downward from the cover 11) via an intermediate pipe 43. The intermediate pipe 43 extends approximately horizontally radially from the downstream end (lower end) of the rotary joint 40 toward both sides. The pair of spray nozzles 41 extend downward (towards the bucket 3) from near both ends of the intermediate pipe 43 (they are suspended). The pair of spray nozzles 41 are in an approximately vertical position and are arranged approximately parallel to each other. The rotary nozzle 42 is connected to one radial end of the intermediate pipe 43 and extends approximately horizontally while bending. The intermediate pipe 43 and the rotary nozzle 42 form approximately an L shape when viewed from above. The other radial end of the intermediate pipe 43 is closed.

[0050] As shown in Figure 6, the tip (lower end) of the spraying nozzle 41 is several tens of millimeters above the upper surface (surface) of the powder P contained in the bucket 3. Preferably, the distance (Y) between the tip of the spraying nozzle 41 and the upper surface (surface) of the powder P is about 40 to 50 mm. Although it is preferable that the tip of the spraying nozzle 41 is away from the upper surface (surface) of the powder P, it is not limited to this, and may be in contact with the surface of the powder P or located slightly below the surface of the powder P.

[0051] <Nozzle function> When the shut-off valve 20 is opened, the high-pressure air stored in the header tank 17 flows into the rotary joint 40, and through the intermediate piping 43, flows into each spray nozzle 41 and the rotating nozzle 42. The high-pressure air is then sprayed from the tips of each spray nozzle 41 and the rotating nozzle 42 (see Figure 6). The nozzle section 4 (intermediate piping 43) rotates around the rotary joint 40 due to the high-pressure air sprayed from the tip of the rotating nozzle 42 (see the dashed arrow in Figure 5). The pair of spray nozzles 41 rotate and spray high-pressure air towards the powder P contained in the bucket 3. As a result, the powder P to be supplied to the dust collector 90 is stirred up in the space above the bucket 3, which is closed by the lid section 11 (see Figure 6). The airborne powder P flows from the discharge pipe 25 into the powder discharge hose 26 (see Figure 6), passes through the powder discharge hose 26, and flows into the suction pipe 92 of the dust collector 90 (see Figure 1).

[0052] (Nozzle details) Each spray nozzle 41 and rotating nozzle 42 is formed from, for example, a copper pipe. Copper pipes are easily deformable, have excellent workability, and possess antibacterial properties. However, each spray nozzle 41 and rotating nozzle 42 is not limited to a copper pipe; they may be pipes made of other metals such as aluminum alloy, or molded pipes made of synthetic resin.

[0053] As shown in Figure 8, nozzles 41 and 42 have a generally circular cross-section, except for the tip portion away from the intermediate pipe 43. The tip portions of nozzles 41 and 42 are flattened and formed to gradually narrow (thin) from the base end to the tip in the axial direction. The open tip portions of nozzles 41 and 42 have a generally elongated cross-section. In detail, when viewed from the axial direction, the opening shape of the tip portions of nozzles 41 and 42 is a rectangle with both ends in the direction of the long side rounded into semicircular shapes. As an example, the diameter (inner diameter (D1)) of the part of nozzles 41 and 42 excluding the tip portion is approximately 6 mm, and its cross-sectional area (S1) is approximately 28 mm². In contrast, the minor axis (inner diameter (D2)) of the open tip surface of nozzles 41 and 42 is approximately 1 mm, the major axis (inner diameter (D3)) is approximately 9 mm, and its cross-sectional area (S2) is approximately 9 mm². The cross-sectional area (S2) of the open tip surfaces of nozzles 41 and 42 is approximately 1 / 3 of the cross-sectional area (S1) of the portion excluding the tip surface, representing a reduction of approximately 68%.

[0054] Assuming that the flow rate (Q) of the high-pressure air flowing through nozzles 41 and 42 is constant, the flow velocity (V) of the high-pressure air flowing through nozzles 41 and 42 can be calculated using the following formula 1. The flow velocity (V2) at the tip of nozzles 41 and 42 is approximately three times the flow velocity (V1) in the portion excluding the tip surface. Therefore, the high-pressure air is accelerated and ejected at the tip of nozzles 41 and 42. Furthermore, since the opening shape of the tip of nozzles 41 and 42 is the elongated hole shape described above, the high-pressure air is ejected while spreading in the direction of its major axis. Note that the opening shape of the tip of nozzles 41 and 42 may be approximately elliptical or approximately rectangular.

[0055] (Math 1) V = Q / S V: Flow velocity of high-pressure air circulating through the nozzle [mm / s] Q: What is the flow rate of the high-pressure air circulating through the nozzle [mm^3 / s]? S: Nozzle cross-sectional area [mm^2]

[0056] <Lifting section> As shown in Figures 5 and 6, the lifting section 5 is housed in the case 2 (case body 10) below the bucket 3. As shown in Figure 9, the lifting section 5 has four guide columns 50, four compression coil springs 51 (elastic members), and four spacers 52. Since the four guide columns 50 are identical in shape, this specification will mainly focus on describing one guide column 50. Similarly, the four compression coil springs 51 and the four spacers 52 will mainly focus on describing one compression coil spring 51 and one spacer 52. Furthermore, for other components that are provided in multiple quantities with the same shape, mainly one component will be described.

[0057] (Guide support) The guide support column 50 is formed in a roughly cylindrical (round bar) shape and is installed in an upright position. The upper part of the guide support column 50 has a tapered surface that gradually narrows towards the upper end. Four support column mounting plates 53 are arranged in a grid pattern on the bottom surface of the case body 10 and are fixed to the bottom surface (see Figures 5 and 6). Each support column mounting plate 53 has a female threaded portion 54 (nut) formed thereon, and the lower part of the guide support column 50 has a male threaded portion 55 that screws into the female threaded portion 54. The guide support column 50 is erected on the bottom surface of the case body 10 by screwing the male threaded portion 55 into the female threaded portion 54 of the support column mounting plate 53. The four support column mounting plates 53 (female threaded portions 54) are arranged to face the four through holes 37 formed in the pair of guide legs 36 of the bucket 3.

[0058] The upper part of the guide column 50 passes through a through hole 37 that is opened in the guide leg portion 36 of the bucket 3 (see Figure 5). The bucket 3 is configured to slide vertically along the guide column 50. The guide column 50 passes through the guide leg portion 36 provided on the bucket 3 and guides the raising and lowering of the bucket 3. The diameter of the through hole 37 is slightly larger than the diameter of the guide column 50, and is formed to ensure the smooth sliding of the guide column 50.

[0059] (Compression coil spring) The compression coil spring 51 is installed so as to wrap around the guide column 50. The free height (natural length) of the compression coil spring 51 is set to be shorter than the height of the guide column 50. Therefore, the portion of the guide column 50 excluding the upper part is inserted into the hollow axial center of the compression coil spring 51. The lower end of the compression coil spring 51 is in contact with the bottom surface of the case body 10, more precisely, with the upper surface of the support column mounting plate 53. The upper end of the compression coil spring 51 is in contact with the bottom surface of the bucket 3, more precisely, with the bottom surface of the guide leg portion 36 (near the edge of the through hole 37). The compression coil spring 51 is installed between the bottom surface of the case body 10 and the bottom surface of the bucket 3, biasing the bucket 3 upward.

[0060] An example of the specifications for the compression coil spring 51 is as follows: Material: SWP-A (piano wire) Wire diameter: 1mm Coil average diameter: 15mm Adjustable height: 200mm Effective number of turns: 20 Spring constant: 0.2 N / mm

[0061] (Spacer) The spacer 52 is formed in a substantially cylindrical shape with a diameter slightly larger than the outer diameter of the compression coil spring 51. The spacer 52 is provided so as to surround the outer circumference of the compression coil spring 51. The height (H) of the spacer 52 (see Figure 12) is set to be longer than the compressed height of the compression coil spring 51. Therefore, the lower side of the compression coil spring 51 (free height) is inserted into the hollow axial center of the spacer 52, and the upper side of the compression coil spring 51 (free height) is exposed from the spacer 52. Also, the height (H) of the spacer 52 is set to be slightly longer than the height of the compression coil spring 51 (load height) when it is subjected to a load from the bucket 3 when full (see Figure 12 described later). The compression coil spring 51 is positioned with a small gap between the outer surface of the guide column 50 and the inner surface of the spacer 52. The guide column 50 and the spacer 52 suppress the warping of the compression coil spring 51 and guide the linear expansion and contraction of the compression coil spring 51.

[0062] <Container support part> As shown in Figures 5 and 10, the four container support sections 6 are provided between the case 2 and the bucket 3, and are arranged at intervals in the direction circumferentially around the outer surface of the bucket 3. Specifically, the four container support sections 6 are located at the four corners when viewed from above the case 2 (case body 10) (see Figure 10). That is, the four container support sections 6 are arranged at 90-degree intervals in the circumferential direction when viewed from above, and the bucket 3 is surrounded by the four container support sections 6. In other words, the two pairs of container support sections 6 are arranged opposite each other on the diagonal of the case body 10 with the bucket 3 in between (see Figure 10). Since the four container support sections 6 have the same structure, this specification will mainly focus on describing one of the container support sections 6.

[0063] As shown in Figures 10 and 11, the container support section 6 includes a cylindrical roller 60 and a horizontally extending, flat support biasing plate 61.

[0064] The roller 60 is positioned with its rotation axis horizontal. Both ends of the rotation axis of the roller 60 are rotatably supported by a U-shaped groove-shaped roller support portion 62 located approximately in the center of the support biasing plate 61. Alternatively, the roller 60 may be rotatably supported on the rotation axis, with both ends of the rotation axis fixed to the roller support portion 62.

[0065] Both sides of the support biasing plate 61 are obtusely bent support fixing portions 63 for fixing to the inner surface of the case body 10 (case 2). The support biasing plate 61 is installed between adjacent side plates that straddle the vertical ridges (up and down ridges) of the case body 10, in a position that intersects the diagonal of the case body 10 (see the dashed line in Figure 10). A pair of support fixing portions 63 of the support biasing plate 61 are fixed to the side plates of the case body 10 via bolts. The support biasing plate 61 is made of, for example, spring stainless steel (e.g., SUS304-WPB) with an elastic effect and a plate thickness of about 1 mm. The support biasing plate 61, excluding the pair of support fixing portions 63, functions as a leaf spring that can be elastically deformed in the radial direction of the bucket 3. The support biasing plate 61 elastically presses the roller 60 against the outer surface of the bucket 3. Specifically, the support biasing plate 61 is deflected so as to bulge outward by approximately 1 to 2 mm in the diameter direction when the roller 60 is in contact with the outer surface of the bucket 3. This causes the outer surface of the roller 60 to be in close contact with the outer surface of the bucket 3. Furthermore, since the upper edge of the bucket 3 is reinforced with the reinforcing plate 30, it can withstand the pressing force received from the roller 60, and deformation of the bucket 3 is prevented.

[0066] [Bucket elevation] The lifting and lowering operation of bucket 3 will be explained with reference to Figure 12. Figure 12 is a side view (partially a cross-sectional view) illustrating the lifting and lowering operation of bucket 3 of the powder supply device 1. Note that in Figure 12, the spacer 52 has been removed from the lifting and lowering section 5 for illustration purposes.

[0067] The lifting unit 5 lowers the bucket 3 as the amount of powder P contained in the bucket 3 increases, and raises the bucket 3 as the amount of powder P contained in the bucket 3 decreases. Specifically, the lifting unit 5 raises and lowers the bucket 3 so as to maintain a constant distance (Y) between the tip of the spraying nozzle 41 and the powder P in the bucket 3. In addition, the four container support units 6 support the bucket 3 so that it can be raised and lowered.

[0068] As shown in the left diagram of Figure 12, for example, when an operator opens the lid 11 and puts powder P (or a storage bag PB containing powder P) into the bucket 3, filling it to a full state (e.g., 10 kg), the four compression coil springs 51 are compressed (shrink) by the weight of the bucket 3 containing the powder P, causing the bucket 3 to descend. The bucket 3 is supported (stops) at a position (height) where the weight of the bucket 3 containing the powder P and the biasing force of each compression coil spring 51 are balanced. The rollers 60 of the container support section 6 also contact the outer surface of the bucket 3 and rotate around the axis as the bucket 3 moves up and down. The guide pillars 50, compression coil springs 51, and spacers 52 are each arranged in a grid pattern of four, and since they apply a generally equal biasing force to the bucket 3, the bucket 3 can be lowered in a nearly parallel manner. In addition, the four container support sections 6 support the descending bucket 3 and suppress the swaying of the bucket 3 in the front-to-back and left-to-right directions.

[0069] Since the height (H) of the spacer 52 is slightly longer than the load height of the compression coil spring 51, a small gap is formed between the upper end of the spacer 52 and the lower surface of the guide leg 36. Furthermore, because the spacer 52 is formed to be longer than the contact height of the compression coil spring 51, and the lower part of the compression coil spring 51 is inserted into the hollow axial center of the spacer 52, even if the bucket 3 is pushed down more than necessary, or if more powder P than necessary is put into the bucket 3, the upper end of the spacer 52 will interfere with the bucket 3, thereby restricting the downward movement of the bucket 3. As a result, the spacer 52 functions as a stopper that restricts the downward movement of the bucket 3, and damage to the compression coil spring 51, such as buckling due to compression to the contact height, can be suppressed.

[0070] When bucket 3 is full, the tip of the spraying nozzle 41 is separated (distance (Y)) from the top surface of the powder P. Also, the reference line 15A of the remaining amount viewing section 15 formed on the case body 10 points to "F" on the remaining amount indicator section 31 fixed to bucket 3. The operator can confirm that bucket 3 is full by visually checking the remaining amount indicator section 31 of bucket 3 through the remaining amount viewing section 15 from outside case 2. Furthermore, if the remaining amount detection sensor 32 is installed to detect a full state, the detection section 35C of the remaining amount detection adjustment plate 35 blocks the light emitted from the light-emitting section of the remaining amount detection sensor 32, and the remaining amount detection sensor 32 transmits a detection signal to the control panel 80. As a result, the control panel 80 determines that the powder P in bucket 3 is full.

[0071] Next, as shown in the right-hand diagram of Figure 12, as the supply of powder P to the dust collector 90 progresses and the amount of powder P in the bucket 3 gradually decreases, the bucket 3 containing the powder P gradually becomes lighter, and the bucket 3 gradually rises due to the repulsive force (restoring force) of the four compression coil springs 51. Since the spring constant of the compression coil springs 51 has a constant linear characteristic, the compression coil springs 51 raise the bucket 3 in proportion to the amount of powder P contained in the bucket 3. In other words, the surface of the powder P in the bucket 3 approaches the tip of the spraying nozzle 41 in proportion to the amount of powder P. As a result, the distance (Y) between the tip of the spraying nozzle 41 and the surface of the powder P is maintained at approximately the same level as when the bucket 3 is full.

[0072] Eventually, when bucket 3 becomes empty (or the amount of powder P reaches its lower limit), the reference line 15A of the remaining amount viewing section 15 formed on the case body 10 points to "E" on the remaining amount indicator section 31 fixed to bucket 3. The operator can visually check the remaining amount indicator section 31 of bucket 3 through the remaining amount viewing section 15 from outside case 2, and confirm that bucket 3 is empty (the amount of powder P remaining) without opening the lid 11. Furthermore, if the remaining amount detection sensor 32 is installed to detect the empty state, the detection section 35C of the remaining amount detection adjustment plate 35 blocks the light emitted from the light-emitting section of the remaining amount detection sensor 32, and the lower remaining amount detection sensor 32 transmits a detection signal to the control panel 80. As a result, the control panel 80 determines that bucket 3 is empty.

[0073] The operator opens the lid 11 and replenishes the bucket 3 with powder P. Alternatively, the operator may visually check the remaining amount indicator 31 through the remaining amount viewing unit 15 before the bucket 3 becomes empty and replenish the bucket 3 with powder P at any time. The remaining amount detection sensor 32 may also be configured to transmit a detection signal before the bucket 3 becomes completely empty. In this case, the remaining amount detection sensor 32 should be positioned above the position where it detects that the bucket 3 is completely empty. Furthermore, the remaining amount detection sensor 32 is not limited to a reflective photosensor; other sensors such as a magnetic sensor may be used. Additionally, a rotating indicator light or the like may be provided (not shown) to notify that the bucket 3 is empty in conjunction with the detection signal from the remaining amount detection sensor 32.

[0074] As described above, the powder supply device 1 according to this embodiment raises and lowers the bucket 3 in accordance with the increase or decrease in the amount of powder P contained in the bucket 3, so that the distance (Y) between the tip of the spraying nozzle 41 (high-pressure air injection port) and the surface (top surface) of the powder P can be kept approximately constant. As a result, the amount of powder P that is blown up by the high-pressure air sprayed from the spraying nozzle 41 can be kept constant regardless of the amount of powder P contained in the bucket 3. As a result, the amount of powder P supplied to the dust collector 90 can be kept constant.

[0075] Furthermore, according to the powder supply device 1 of this embodiment, the bucket 3 can be raised and lowered by balancing the combined weight of the bucket 3 and the powder P with the biasing force of the compression coil spring 51. This allows the lifting and lowering section 5 to be constructed simply and at low cost compared to cases where the bucket 3 is raised and lowered using a drive source such as a motor or a power transmission mechanism such as gears.

[0076] Furthermore, according to the powder supply device 1 of this embodiment, the bucket 3 can be raised and lowered in a stable position by the four guide columns 50 and the four compression coil springs 51. In addition, since the guide columns 50 are inserted into the hollow axial portions of the compression coil springs 51, the compression coil springs 51 can be expanded and contracted along the guide columns 50.

[0077] Furthermore, according to the powder supply device 1 of this embodiment, since the four container support parts 6 are provided at intervals in the circumferential direction between the case 2 and the bucket 3, the bucket 3 can be raised and lowered while maintaining a stable posture.

[0078] Furthermore, according to the powder supply device 1 of this embodiment, the roller 60 of the container support section 6 is biased by the support biasing plate 61 and contacts the outer surface of the bucket 3, and rotates as the bucket 3 is raised and lowered, thus enabling smooth and stable raising and lowering of the bucket 3. In addition, since the support biasing plate 61 has the function of pivotally supporting the roller 60 and the function of pressing the roller 60 against the outer surface of the bucket 3, the number of parts can be reduced compared to when both functions are realized by separate parts, and the manufacturing cost of the container support section 6 can be reduced.

[0079] Furthermore, according to the powder supply device 1 of this embodiment, by housing a cylindrical bucket 3 in a rectangular tubular case 2, the four dead spaces created at the four corners of the case 2 can be effectively utilized as space for arranging four container support parts 6. As a result, it is not necessary to enlarge the case 2 in order to arrange the four container support parts 6 between the case 2 and the bucket 3, and the powder supply device 1 can be made more compact.

[0080] In the powder supply device 1 according to this embodiment, the nozzle section 4 had a pair of spraying nozzles 41 and one rotating nozzle 42, but the present invention is not limited to this. The spraying nozzles 41 may be provided as one or as three or more (neither shown). Also, for example, a pair of rotating nozzles 42 may be provided at both ends of the intermediate pipe 43 (not shown). In this case, the pair of rotating nozzles 42 may be arranged to spray high-pressure air in opposite directions. Also, although the rotating nozzles 42 were bent and extended linearly relative to the intermediate pipe 43, the invention is not limited to this and may be curved along the inner circumferential surface of the bucket 3 (not shown).

[0081] Furthermore, in the powder supply device 1 according to this embodiment, the spraying nozzle 41 and the rotating nozzle 42 were generally the same shape, but this is not limited to this, and they may have different shapes (cross-sectional shape, diameter, etc.) (not shown).

[0082] Furthermore, in the powder supply device 1 according to this embodiment, the compression coil spring 51 of the lifting section 5 biased the bucket 3 upward, but the present invention is not limited to this. For example, instead of the compression coil spring 51, an elastic member such as rubber may bias the bucket 3 upward (not shown). Also, in the lifting section 5 described above, four compression coil springs 51 etc. were provided, but the invention is not limited to this, and one or more compression coil springs 51 etc. may be provided (not shown).

[0083] Furthermore, in the powder supply device 1 according to this embodiment, the lifting unit 5 raised and lowered the bucket 3 using a compression coil spring 51 or the like, but the present invention is not limited to this. For example, the bucket 3 may be raised and lowered using other lifting units, such as a drive source like a motor or a power transmission mechanism like gears (not shown).

[0084] Furthermore, in the powder supply device 1 according to this embodiment, the four container support parts 6 that support the bucket 3 are arranged at 90-degree intervals in the circumferential direction when viewed from a plane, but the present invention is not limited to this. For example, three container support parts 6 may be arranged at 120-degree intervals in the circumferential direction when viewed from a plane (not shown).

[0085] [Various settings for powder supply equipment] Next, we will describe the various settings used when forming a pre-coat layer on the filter of the dust collector 90 using the powder supply device 1 according to this embodiment.

[0086] The operator operates the control panel 18 of the powder supply device 1 to set the opening and closing times of the on / off valve 20, etc. For example, the standard settings are: the injection time of high-pressure air (compressed air) from the nozzle section 4 (nozzles 41, 42) (hereinafter referred to as "injection ON time") is 5 seconds; the injection stop time of the high-pressure air (hereinafter referred to as "injection OFF time") is 10 seconds; and the time from the start of operation of the dust collector 90 until the high-pressure air is injected (hereinafter referred to as "on-delay time") is 5 seconds. The settings entered by operating the control panel 18, the standard settings, and other calculation results from the arithmetic processing unit 81 are stored in the storage device 82 of the control panel 80.

[0087] The powder supply device 1 (control panel 80) intermittently injects high-pressure air from the tips of nozzles 41 and 42 by alternately repeating injection ON time and injection OFF time over a predetermined period of time. As a result, powder P is supplied to the dust collector 90, and a pre-coat layer is formed on the filter. The predetermined period of time during which the injection ON time and injection OFF time are repeated (hereinafter referred to as "pre-coat time (PT)") is calculated by formula 2.

[0088] (Math 2) PT = (A × B) / C A: Total filter area [m^2] B: Amount of powder required per unit area of ​​the filter [g / m^2] C: Powder supply amount [g / min] PT: Pre-court time [min]

[0089] The total filter area (A) is calculated based on the number of filters used in the dust collector 90 (e.g., 20 m²). The amount of powder required per unit area of ​​the filter (B) is preset for each filter (e.g., 200 g / m²). The powder supply rate (C) is calculated by the control panel 80 when various conditions (type of powder P, adjustment pressure at the regulator 16, etc.), injection ON time, and injection OFF time are input from the operation unit 18 (e.g., in the range of 10 to 100 g / min). The control panel 80 calculates the pre-coat time (PT) based on A to C described above (e.g., 40 min). The control panel 80 may also adjust (increase or decrease) the injection ON time, injection OFF time, on-delay time, and pre-coat time (PT) depending on the type of powder P used. For example, if the powder P is calcium carbonate, it is preferable to set the injection ON time and pre-coat time (PT) longer than the standard settings because its fluidity is worse than that of calcium hydroxide.

[0090] Alternatively, instead of calculating the pre-coating time (PT), the formation of a pre-coat layer on the filter can be determined by using the filter differential pressure (ΔP) of the dust collector 90. Specifically, when powder P is supplied from the powder supply device 1 to the dust collector 90 and the powder P adheres to the surface of the filter (filter material) (forming a pre-coat layer), the filter differential pressure (ΔP) gradually increases. The completion of the pre-coating process can be considered to be when the filter differential pressure (ΔP) measured by the differential pressure measuring unit 97 of the dust collector 90 reaches a preset value (ΔP1). This value (ΔP1) is stored in the storage device 82 beforehand.

[0091] Furthermore, if the on-off valve 20 of the powder supply device 1 is opened before or simultaneously with the rotation of the suction fan 94 of the dust collector 90, the inside of case 2 becomes positive pressure due to the high-pressure air sprayed from nozzles 41 and 42. As a result, there is a risk that the powder P, which is stirred up by the high-pressure air sprayed from nozzles 41 and 42, may leak out of case 2 to the outside. Therefore, an on-delay time is set in the powder supply device 1. As a result, the on-off valve 20 of the powder supply device 1 is opened after the on-delay time has elapsed from the start of operation of the dust collector 90 (start of rotation of the suction fan 94), so that the inside of case 2 becomes negative pressure due to the suction operation of the dust collector 90. Therefore, it is possible to suppress the leakage of the stirred-up powder P from case 2 to the outside.

[0092] [Dust collection method] Next, with reference to Figure 13, a dust collection method will be described in which the dust collector 90 and the powder supply device 1 are operated to collect (capture) dust. Figure 13 is a time chart of the dust collection method using the powder supply device 1 and the dust collector 90.

[0093] The dust collection method comprises a pre-coating process, a dust collection process, and a filter cleaning process.

[0094] <Pre-coating process> The pre-coating process is performed before the dust collection process, which involves sucking up and collecting dust. In the pre-coating process, the control panel 80 sends an operation signal (ON) to the suction fan 94 and rotates the suction fan 94 at a low speed (lower than the speed used for dust suction) based on the output of the rotation speed measuring unit 96. While the suction fan 94 continues to rotate, the control panel 80 starts controlling the opening and closing of the on-off valve 20 with an on-delay time delay from the time the operation signal is sent. The control panel 80 repeatedly opens and closes the on-off valve 20 during the pre-coating time (PT). The control panel 80 controls the opening and closing time of the on-off valve 20 based on the injection ON time and injection OFF time. The powder P in the bucket 3 is blown up by the high-pressure air injected from the spraying nozzle 41, passes through the discharge pipe 25 and the powder discharge hose 26, and is supplied to the dust collector 90 (exhaust port 93). The powder P then adheres to the filter, forming a pre-coating layer on the filter.

[0095] Once the pre-coating time (PT) has elapsed, the control panel 80 sends a stop signal to the suction fan 94 (OFF), closes the on / off valve 20, and ends the pre-coating process. Alternatively, the control panel 80 may end the pre-coating process when the measurement result (filter differential pressure (ΔP)) of the differential pressure measuring unit 97 reaches a preset value (ΔP1) instead of the pre-coating time (PT).

[0096] In the pre-coating process, the processing equipment is stopped, no dust is generated, and the dust collector 90 does not collect dust. Alternatively, the opening of the damper 92A may be reduced to allow the suction fan 94 to rotate at a low speed. In this case, the opening of the damper 92A should be adjusted so that the outflow rate (flow rate (Q2) (see Figure 1)) from the discharge pipe 25 of the powder supply device 1 is greater than the inflow rate (flow rate (Q1) (see Figure 1)) from the suction pipe 92 of the dust collector 90.

[0097] <Dust collection process> Once the pre-coating process is complete, the control panel 80 pauses briefly before proceeding to the dust collection process. In the dust collection process, prior to the start of operation of the processing equipment (start of processing) (simultaneously with the start of operation), the control panel 80 sends an operation signal (ON) to the suction fan 94, and rotates the suction fan 94 at high speed (the rotation speed required for dust collection) based on the output of the rotation speed measuring unit 96. As a result, dust generated from the processing equipment is sucked into the dust collector 90 and collected in the filter (pre-coating layer).

[0098] When the control panel 80 detects that the measurement result (filter differential pressure (ΔP)) from the differential pressure measuring unit 97 has reached a preset value (ΔP2), it sends a backwash signal (ON) to the dust removal device 95, causing the dust removal device 95 to inject compressed air (pulse jet) (filter backwash operation). This removes the dust collected on the filter (filter material), and the filter differential pressure (ΔP) decreases. Immediately after the filter backwash operation, the control panel 80 opens the on-off valve 20, supplying powder P from the powder supply device 1 to the dust collector 90 (pre-coat treatment). The filter backwash operation and the pre-coat treatment are performed alternately and intermittently. It is preferable to stagger the timing of the filter backwash operation and the pre-coat treatment. This allows the pre-coat treatment to be performed on the filter after the dust has been removed, thus forming an appropriate pre-coat layer on the filter surface. The value (ΔP2) is stored in the storage device 82 beforehand.

[0099] When the processing equipment has finished operating (processing is complete), the control panel 80 sends a stop signal to the suction fan 94 (turns it OFF), and the dust collection process ends.

[0100] <Filter cleaning process> Once the dust collection process is complete, the control panel 80 executes the filter cleaning process. In the filter cleaning process, with the suction fan 94 stopped, the control panel 80 sends a backwash signal (ON) to the dust removal device 95, causing the dust removal device 95 to inject compressed air (pulse jet). This removes the dust collected on the filter (filter material). It is preferable to perform the filter backwash operation multiple times. The processing device and powder supply device 1 are also stopped (paused).

[0101] The dust collection method, which involves operating the dust collector 90 and the powder supply device 1 to collect (capture) dust, is thus completed.

[0102] The above description of the embodiments illustrates one aspect of the powder supply device according to the present invention, and the technical scope of the present invention is not limited to the above embodiments. The present invention may be modified, substituted, or transformed in various ways without departing from the spirit of the technical idea, and the claims include all embodiments that may fall within the scope of the technical idea. [Industrial applicability]

[0103] The present invention can be used in a powder supply device for forming a pre-coat layer by adhering powder to the filter of a dust collector that collects flammable or sticky (adherent) dust. [Explanation of Symbols]

[0104] 1 Powder feeding device 2 cases 3 buckets 4. Nozzle section 5. Lifting section 6 Container support part 15. Battery level indicator 31. Remaining amount indicator section 36 Guide leg section (guide section) 50 Guide posts 51 Compression coil spring (elastic member) 52 Spacers 60 rollers 61 Support bias plate 90 Dust collector

Claims

1. A powder supply device that supplies powder to a dust collector, A bucket for containing the aforementioned powder, A nozzle unit that blows high-pressure air into the powder contained in the bucket and supplies the powder to the dust collector, A powder supply device characterized by comprising a lifting unit that lowers the bucket as the amount of powder contained in the bucket increases, and raises the bucket as the amount of powder contained in the bucket decreases.

2. The powder supply device according to claim 1, characterized in that the lifting section has an elastic member that contacts the lower surface of the bucket and biases the bucket upward.

3. The aforementioned lifting mechanism is Multiple guide columns are provided in an upright position, pass through the guide portion provided on the bucket, and guide the raising and lowering of the bucket. The powder supply device according to claim 1, further comprising a plurality of compression coil springs provided so as to wrap around each of the guide pillars and contacting the lower surface of the bucket to bias the bucket upward.

4. The lifting mechanism further comprises a plurality of spacers provided so as to surround the outer circumference of each of the compression coil springs. The powder supply device according to claim 3, characterized in that the height of the spacer is set to be longer than the contact height of the compression coil spring.

5. A case housing the bucket and the lifting mechanism, The powder supply device according to any one of claims 1 to 4, further comprising: a plurality of container support parts provided between the case and the bucket, spaced apart in a direction circumferential to the outer surface of the bucket, and supporting the bucket so that it can be raised and lowered.

6. Each of the container support parts is, A roller that contacts the outer surface of the bucket and rotates around its axis as the bucket moves up and down, The powder supply device according to claim 5, further comprising a support biasing plate that rotatably supports the roller, is fixed to the case, and presses the roller against the outer surface of the bucket.

7. The bucket is formed in a cylindrical shape having a bottom surface, The case is formed in the shape of a rectangular tube having a bottom surface, The multiple container support parts are arranged at the four corners when the case is viewed from above. The powder supply device according to claim 6, characterized in that each of the support biasing plates is installed between adjacent side plates on either side of the case, with respect to the case's diagonal.

8. A remaining amount indicator is fixed to the outer surface of the bucket, which indicates the amount of powder contained in the bucket. The powder supply device according to claim 5, characterized in that the case has a remaining amount viewing section formed therein that allows the remaining amount indicator section fixed to the bucket to be viewed from the outside.

Images