JP2012240804A - Powder supply device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a powder supply device that can perform proper supply by securing measuring accuracy of a flow rate of powder to a supply destination, even when a supply quantity of the powder per a unit time is a very small quantity.SOLUTION: This powder supply device includes: a dam part 9 for damming up a part of the powder pw trying to proceed to the downstream end 2a by vibration of a trough 2 by forming a projection shape of rising from a carrying surface 20, when supplying the powder to the supply destination by dropping from the downstream end 2a of the trough 2 by moving the powder pw existing on the carrying surface 20 of the trough 2 along the predetermined carrying direction X, by vibrating the trough 2 for receiving supply of the powder pw from a hopper 1 by an electromagnetic driving part 3; a light emitting part 40 for projecting the light to the powder pw dropping from the downstream end 2a; a light sensor 41 for receiving the light reflected by the powder pw, a flow rate detecting part 42 for detecting a quantity of dropped powder pw based on a light receiving quantity of the light sensor 41, and a vibration control part 5 for controlling the vibration excited by the electromagnetic driving part 3 to provide a powder carrying speed of becoming a target flow rate in a detecting value per the unit time by the flow rate detecting part 42.

Description

  The present invention relates to a powder supply apparatus that supplies powder by vibration.

  The powder supply device is a device that supplies powder to a supply destination by vibration that is vibrated by a vibration means. In order to supply a desired amount of powder per unit time, the powder supply amount is estimated. It is an apparatus for controlling vibrations by the vibration means.

  As an example of this type of powder supply apparatus, Patent Document 1 discloses a hopper that stores powder, a supply pipe that serves as a conveyance path for conveying powder from the hopper to a supply destination, and a vibration of the supply pipe. Weight change detected by the load cell using the vibration means, a hopper including the weight of the powder, and a load cell for measuring the weight of the conveyance path, and the fact that the weight measured with the supply of the powder decreases. An apparatus for feedback-controlling vibrations by the vibration excitation means is disclosed.

JP 10-1442034 A

  However, in the weight measurement method in which the supply amount of powder as described above is estimated by a change in weight, for example, when a minute amount such as several grams per minute is to be supplied, a hopper, a conveyance path (supply pipe), and a vibration means are included. In addition, for a few tens of kilograms, it is necessary to measure a change in weight in grams or milligrams, and it is difficult to ensure measurement accuracy. Therefore, in order to supply such a small amount of powder per unit time, a powder supply apparatus having a new measurement method for detecting the flow rate of the powder to the supply destination is required.

  The present invention has been made paying attention to such problems, and its purpose is to measure the flow rate of the powder to the supply destination even if the supply amount of the powder per unit time is very small. Is to provide a powder supply apparatus that can ensure proper supply.

  In order to achieve this object, the present invention takes the following measures.

  That is, the powder supply apparatus according to the present invention moves the trough that receives the supply of powder from the hopper with the vibrating means, thereby moving the powder on the transport surface of the trough along a predetermined transport direction. A powder supply device that drops from the downstream end of the trough and supplies it to a supply destination, and has a protruding shape that rises from the transfer surface along a direction intersecting the predetermined transfer direction, and is supplied from the hopper And a weir portion that blocks a part of the powder that is directed to the downstream end by vibration of the trough, and throws against the powder falling from the downstream end via the weir portion and the downstream end. A light emitting unit that emits light, an optical sensor that receives light reflected from the powder emitted from the light emitting unit, a flow rate detection unit that detects the amount of powder falling from the downstream end based on the amount of light received by the optical sensor, and Unit time by the flow rate detector Ri of such detected values are obtained the conveying speed of the powder as a target flow rate, characterized by comprising a vibration control unit for controlling the vibration excitation by the exciting means.

  In this way, the powder transported by vibration is dropped from the downstream end of the trough, the light emitting part projects light onto the falling powder, the reflected light is detected by the optical sensor, and the powder dropped based on the amount of reflected light Therefore, even if the flow rate of the powder is very small, it is possible to detect the flow rate of the powder with higher accuracy than when measuring by weight including the hopper and the trough. On the other hand, if the powder piled up on the conveying surface of the trough falls from the downstream end in a solid state, a plurality of powders that enter the light projecting region of the light emitting unit are superposed in the light projecting direction, and the light sensor Although it is considered that accurate supply amount detection cannot be performed, in the present invention, a plurality of powders going to the downstream end are not superposed in the vertical direction by a protruding weir portion standing up from the trough conveying surface. Since it climbs over the top of the weir part, the powder falling from the downstream end of the trough and entering the light emitting area of the light emitting part is reduced or eliminated, and the flow rate detection accuracy by the optical sensor can be ensured. Therefore, the vibration to be applied to the trough is controlled so that the powder conveyance speed at which the detected value per unit time by the flow rate detection unit becomes the target flow rate can be obtained. It is possible to provide a lost powder supply apparatus.

  In order to reduce a plurality of powders entering the light projecting region of the light emitting unit from being polymerized in the light projecting direction and to enable appropriate flow rate detection, a single powder is formed on the transport surface. A plurality of grooves that are set to have a groove width that allows passage and extend from the downstream end toward the upstream side are formed along the downstream end, and the protruding direction of the powder guided by the groove is It is preferable that all the grooves are set to face the same direction in plan view.

  In order to pursue an appropriate flow rate detection, it is desirable that the vibration angle be set so that the powder conveyance speed increases from the upstream side to the downstream side of the conveyance surface.

  In order to supply the powder which is oxidized by oxygen in the air while preventing the oxidation, the container includes a container for storing at least the hopper and the trough, and the container contains a vacuum environment or an inert gas. It is effective that the pressure is reduced and filled.

  In order to reduce powder damage and trough wear, it is desirable to provide charging means for charging the powder or the conveying surface.

  In the present invention, as described above, the light emitting part projects light onto the powder dropped from the downstream end of the trough, and the reflected light is detected by an optical sensor, and the amount of powder dropped based on the amount of reflected light is detected. Therefore, even when the flow rate of the powder is very small, it is possible to detect the flow rate of the powder with higher accuracy than when measuring by weight including the hopper and the trough. In addition, the protruding dam that stands up from the trough transport surface climbs over the top of the dam in a state where a plurality of powders going to the downstream end do not overlap vertically, so it falls from the tip of the trough. As a result, the powder entering the light projecting region of the light emitting unit is suppressed or eliminated from being polymerized in the light projecting direction, and accurate flow rate detection accuracy by the optical sensor can be secured. Therefore, the vibration to be applied to the trough is controlled so that the powder conveyance speed at which the detected value per unit time by the flow rate detection unit becomes the target flow rate can be obtained. It is possible to provide a lost powder supply apparatus.

The block diagram which shows typically the powder supply apparatus which concerns on one Embodiment of this invention. The figure which shows the structure of a trough typically. Explanatory drawing regarding the vibration angle of a trough. The figure which shows the relationship between the light reception amount of an optical sensor, and the supply amount of powder. The side view which shows typically the positional relationship of an optical sensor and the downstream end of a trough.

  Hereinafter, a powder supply apparatus according to an embodiment of the present invention will be described with reference to the drawings.

  As shown in FIGS. 1 and 2, the powder supply device transports the powder pw upon receiving the powder pw from the hopper 1 for storing the powder pw as a supply object, and the hopper 1. The trough 2 and the electromagnetic drive unit 3 as a vibration means for vibrating the trough 2 are vibrated, and the trough 2 is vibrated by the electromagnetic drive unit 3 as the vibration means. It is an apparatus that moves the powder pw on the top along a predetermined conveying direction X, drops it from the downstream end 2a of the trough 2, and supplies it to the supply destination. Further, in order to supply a desired amount of powder pw per unit time, a flow rate detection means 4 for detecting the amount (flow rate) of the powder pw falling from the downstream end 2a of the trough 2 toward the supply destination, and a flow rate detection A vibration control unit 5 that controls vibrations to be vibrated by the electromagnetic drive unit 3 (vibration unit) based on the detection result of the unit 4 is provided. Furthermore, for example, when the powder pw is oxidized by oxygen in the air, the container 6 for storing at least the hopper 1 and the trough 2 is provided in order to prevent the powder pw from being oxidized.

  As shown in FIG. 1, the storage container 6 has a shape in which a horizontal cylinder 60 whose axial direction is horizontal and a vertical cylinder 61 whose axial direction is vertical are combined, and includes a trough 2. And the hopper 1 are mainly stored. The storage container 6 connects a vacuum pump 62 for making the storage space SP in the storage container 6 a vacuum environment or a reduced pressure environment, and a purge unit 63 for purging the storage container 6 with an inert gas such as nitrogen. It is configured to be possible. The inside of the storage container 6 is set to a reduced pressure environment in which a nitrogen purge is performed and the pressure is reduced, and an inert gas such as nitrogen is filled. The pressure as the degree of vacuum is set to 8 to 10 torr (torr).

  As shown in FIG. 2A, the trough 2 has a substantially rectangular shape in plan view, and a cross section perpendicular to the longitudinal direction has an upward U-shape, and the longitudinal direction is defined as a predetermined conveying direction. As X, a conveying surface 20 for conveying the powder pw along a predetermined conveying direction X is set. As shown in FIGS. 2B and 2C, the conveying surface 20 is set to have a groove width w1 that allows the passage of a single powder pw and from the downstream end 2a toward the upstream side X2. A plurality of extending grooves 21 and 21 are formed along the downstream end 2a. The cross section of the groove 21 is U-shaped, and the groove width w1 is set so as to satisfy the condition of w0 <w1 <2 × w0 when the diameter of the powder pw is w0. In the present embodiment, a powder pw having a diameter w0 of 100 to 500 μm is a conveyance target. Further, by forming all the grooves 21 and 21 so as to extend along the predetermined conveying direction X, the pop-out direction of the powder pw guided by the groove side walls 21a and 21a constituting the grooves 21 is set to all the grooves 21 and 21. 21 is set to face the same direction in plan view. As shown in FIG. 1, a funnel-shaped recovery unit 7 is provided below the downstream end 2a of the trough 2 to receive the dropped powder pw and guide it to the supply destination.

  Further, as shown in FIG. 1, support means 8 for movably supporting the trough 2 is provided. The support means 8 includes a movable block 81 to which the bottom of the trough 2 is attached, a fixed block 82 that is fixed to the bottom of the container 6 through the vibration isolating rubbers 85 and 85 and the base 86, and the movable block 81 to be fixed. Plate springs 83 and 84 are connected to the block 82 and paired with the upstream side X2 and the downstream side X1. The electromagnetic drive unit 3 serving as a vibration means is configured between the movable block 81 and the fixed block 82, and generates vibration in the trough 2 by applying an electromagnetic attractive force between the blocks 81 and 82. Specifically, an electromagnet formed by winding a coil (not shown) around an iron core is attached to the fixed block 82, and the trough 2 is vibrated by energizing the coil (not shown). As shown in FIG. 1, the powder pw on the transport surface 20 of the trough 2 moves toward a predetermined transport direction X. Further, the leaf spring 83 on the upstream side X2 of the pair of leaf springs 83 and 84 is attached in a posture in which the plate surface stands up along the vertical direction, whereas the leaf spring on the downstream side X1. 84 is mounted in a slightly laid posture such that its plate surface intersects the vertical direction. That is, by changing the postures of the two leaf springs 83 and 84, the vibration direction of the upstream side X2 of the trough 2 and the vibration direction of the downstream side X1 are made different as shown schematically in FIG. The vibration angle θ is set so that the conveying speed of the powder pw increases from the upstream side X2 to the downstream side X1. The vibration angle θ at which the conveyance speed becomes the fastest is determined according to the type of the powder pw, the material of the trough 2, and the like. The conveyance speed decreases as the angle becomes smaller than the fastest vibration angle θ. The conveyance speed decreases as the angle becomes larger than the fastest vibration angle θ. In the present embodiment, the vibration angle is set so as to increase from the upstream side X2 toward the downstream side X1 so that the vibration angle of the downstream side X1 approaches the fastest vibration angle with respect to the vibration angle of the upstream side X2. .

  As shown in FIGS. 1 and 2 (a), the hopper 1 has a cylindrical shape having a replenishing port 1a at the upper portion and a supplying port 1b at the lower portion, and is formed in a funnel shape that gradually narrows as the lower portion goes downward. In addition, the supply port 1b at the lowermost end of the funnel is formed as a long long hole along a direction orthogonal to the predetermined transport direction X, and the supply port 1b and the transport surface 20 of the trough 2 are close to each other. The hopper 1 is fixed to the storage container 6 via a fixture 6X. The powder pw stored in the hopper 1 is supplied to the trough 2 by its own weight.

  The flow rate detection means 4 includes a light emitting unit 40 such as an LED that projects light onto the powder pw falling from the downstream end 2a, an optical sensor 41 that receives light emitted from the light emitting unit 40 and reflected by the powder pw, And a flow rate detection unit 42 that detects the amount of the powder pw dropped from the downstream end 2a based on the amount of light received by the optical sensor 41. The light emitting unit 40 and the optical sensor 41 are attached to the base 86 via the bracket 43 so as to be positioned below the trough 2. The light projecting direction of the light emitting unit 40 is set so as to face obliquely upward, and an antireflection plate 44 for preventing light reflection extends in the vertical direction at the light projecting destination, and the collecting unit 7. As a scaffolding. The antireflection plate 44 also serves as the collection unit 7. In addition, even if the powder falls from any part of the downstream end 2a of the transport surface 20, a plurality of light emitting units 40 are arranged along the direction orthogonal to the transport direction X so that light can be irradiated. doing. In accordance with this, as shown in FIG. 5, a plurality of optical sensors 41 are also arranged along a direction orthogonal to the transport direction X (the trough width direction). The plurality of optical sensors 41 and 41 are arranged in a staggered manner along the width direction of the trough 2 by overlapping a part of each light receiving surface 41a in the vertical direction so as to eliminate light reception leakage.

  As shown in FIG. 1, the powder pw is dropped from the downstream end 2a by the vibration of the trough 2, the light emitting unit 40 projects the falling powder pw, the reflected light is detected by the optical sensor 41, and the reflected light is reflected. When configured to detect the amount (flow rate) of the powder pw dropped based on the amount of light, if the powder pw piled on the conveying surface 20 of the trough 2 falls from the downstream end 2a in a solid state, It is conceivable that a plurality of powders pw that enter the light projecting region of the light emitting unit 40 are superposed in the light projecting direction of the light emitting unit 40, making it impossible to accurately detect the supply amount by the optical sensor 41.

  Therefore, in the present embodiment, as shown in FIGS. 1 and 2A, the downstream side X1 of the portion of the conveying surface 20 to which the powder pw is supplied from the hopper 1 is orthogonal to the predetermined conveying direction X. A weir portion 9 is provided that has a protruding shape standing up from the conveying surface 20 along the direction to be closed and blocks a part of the powder pw supplied from the hopper 1 and going toward the downstream end 2a by the vibration of the trough 2. ing. When such a weir portion 9 is provided, the plurality of powders pw going to the downstream end 2a due to the vibration of the trough 2 get over the protruding top without moving in the vertical direction Y and move to the downstream end 2a. In addition, the powder pw falling from the downstream end 2a of the trough 2 and entering the light projecting region of the light emitting unit 40 is reduced or eliminated from being polymerized in the light projecting direction.

  As shown in FIG. 1, the flow rate detection unit 42 is realized by a control unit Co (also referred to as a controller) that is provided outside the container 6 and includes a microcomputer unit that includes a CPU, a memory, and an interface (not shown). As shown in FIG. 4, received light information 45 in which a supply amount of the powder pw and a received light amount by the optical sensor 41 are associated with each other under a certain pressure is previously stored in a memory and detected by the optical sensor 41. Based on the received light amount per unit time and the received light information 45, the amount of the powder pw dropped from the downstream end 2a is detected. The relationship between the supply amount of the powder pw and the amount of received light is a substantially linear relationship, but the gradient changes according to the pressure.

  Returning to FIG. 1, the vibration control unit 5 is realized by the control unit Co. The vibration control unit 5 vibrates the powder so that the detected value per unit time by the flow rate detection unit 42 can obtain the conveyance speed of the powder. The vibration to be vibrated by the electromagnetic drive unit 3 is controlled. Specifically, the voltage applied to the electromagnetic drive unit 3 is controlled in a state where the vibration frequency is kept constant so that the target light amount is obtained. For example, when the detected light quantity is insufficient for the target light quantity, the applied voltage is increased. As a result, the current also increases, so that the amplitude of the vibration excited by the trough 2 increases, the conveyance speed of the powder pw increases, and as a result, the amount of the falling powder pw increases and is detected. The amount of light increases toward the target amount of light. On the contrary, when the detected light quantity exceeds the target light quantity, the applied voltage is reduced. As a result, the current also decreases, so that the amplitude of the vibration excited on the trough 2 decreases, the conveyance speed of the powder pw decreases, and as a result, the amount of the falling powder decreases and is detected. The amount of light decreases toward the target amount of light. In this embodiment, the voltage control method is adopted, but a current control method that changes the current value according to the detected light amount and a frequency control method that changes the frequency according to the detected light amount are adopted. Also good.

  In the above configuration, it was found that a large amount of powder pw is temporarily supplied when the powder pw is being transported and returned to the normal atmospheric state (1 atm) from the reduced pressure environment. This is because in the reduced pressure environment, the moisture in the container 6 is low, that is, the humidity is low, so that the powder pw is charged with static electricity and the conveying surface 20 from the weir portion 9 to the downstream end 2a is charged. It is considered that the powder pw is attached to the entire surface, and another powder pw moves on the attached powder pw. Then, when returning to the normal atmospheric state from the reduced pressure environment, the humidity in the container 6 returns, the charge of the powder pw is lost, the adhesion is released, and a large amount of the adhered powder pw is conveyed. It is thought that. That is, in the present embodiment, a means such as a vacuum pump that places the inside of the container 6 in a vacuum environment or a reduced pressure environment also serves as the charging means 6X that charges the powder pw, and thereby the powder pw that moves by vibration. Is not directly in contact with the trough, and it is considered that the powder pw to be conveyed is prevented from being scraped by the trough 2 and from being worn out. Of course, a charging means for charging the conveying surface 20 by applying a voltage to the trough 2 itself may be provided, and the powder pw may be adhered by charging the conveying surface 20.

  As described above, the powder supply apparatus according to the present embodiment vibrates the trough 2 that receives the supply of the powder pw from the hopper 1 with the electromagnetic drive unit 3 that serves as the vibration means, so Is a powder supply device that moves the powder pw along the predetermined conveyance direction X, drops it from the downstream end 2a of the trough 2, and supplies it to the supply destination, along the direction orthogonal to the predetermined conveyance direction X A weir portion 9 that has a protruding shape standing from the conveying surface 20 and blocks a part of the powder pw supplied from the hopper 1 and directed to the downstream end 2a by the vibration of the trough 2, and the weir portion 9 and the downstream A light emitting unit 40 that projects light onto the powder pw falling from the downstream end 2a via the end 2a, a light sensor 41 that receives the light irradiated from the light emitting unit 40 and reflected by the powder pw, Powder dropped from downstream end 2a based on the amount of light received A flow rate detection unit 42 that detects the amount of pw, and an electromagnetic drive unit 3 that serves as a vibration means so as to obtain a conveyance speed of the powder pw at which the detection value per unit time by the flow rate detection unit 42 becomes a target flow rate. And a vibration control unit 5 that controls vibrations to be vibrated.

  In this way, the powder pw conveyed by vibration is dropped from the downstream end 2a of the trough 2, the light emitting unit 40 projects the falling powder pw, and the reflected light is detected by the optical sensor 41. Since the amount of the powder pw that has dropped is detected based on the above, even if the flow rate of the powder pw is very small, the flow rate of the powder pw is more accurate than when measuring by weight including the hopper 1 and trough 2. It becomes possible to detect. On the other hand, when the powder pw piled up on the conveying surface 20 of the trough 2 is solidified and falls from the downstream end 2a, a plurality of powders pw entering the light projecting region of the light emitting unit 40 are superposed in the light projecting direction. Therefore, although it is considered that accurate detection of the supply amount by the optical sensor 41 cannot be performed, in the present embodiment, the dam portion 9 that protrudes from the conveying surface 20 of the trough 2 tries to go to the downstream end 2a. Since the plurality of powders pw does not overlap in the vertical direction and climbs over the top of the dam part 9, the powder pw that falls from the downstream end 2a of the trough 2 and enters the light projecting region of the light emitting unit 40 in the light projecting direction. Polymerization is suppressed or eliminated, and the flow rate detection accuracy by the optical sensor 41 can be secured. Therefore, since the vibration to be applied to the trough 2 is controlled so that the detected value per unit time by the flow rate detection unit 42 can obtain the conveyance speed of the powder pw having the target flow rate, an error from the target flow rate is controlled. It is possible to provide a powder supply apparatus that reduces or eliminates the above.

  In particular, in the present embodiment, a groove 21 that is set to a groove width w1 that allows passage of a single powder pw and extends from the downstream end 2a toward the upstream side X2 is formed in the downstream end 2a. Are formed so that the protruding direction of the powder pw guided by the groove side walls 21a and 21a constituting the groove 21 is set so that all the grooves 21 and 21 face the same direction in plan view. Therefore, the plurality of powders pw jump out in the same direction in plan view by the plurality of grooves 21 and 21 formed along the downstream end 2a and enter the light projecting region of the light emitting unit 40. It is possible to reduce pw polymerization in the light projecting direction and to detect an appropriate flow rate.

  Furthermore, in this embodiment, since the vibration angle is set so that the conveyance speed of the powder pw increases from the upstream side X2 to the downstream side X1 of the conveyance surface 20, a plurality of powders pw are arranged in the conveyance direction. Since the speed of the powder pw on the advancing side is faster than the speed of the powder pw on the lagging side and the powder pw separates back and forth, It is possible to reduce the amount of polymerization in the light projecting direction when the light enters the light projecting region, and to detect the flow rate more appropriately.

  Furthermore, in the present embodiment, the storage container 6 that stores at least the hopper 1 and the trough 2 is provided, and the interior of the storage container 6 is set in a reduced pressure environment filled with an inert gas, so that it is oxidized by oxygen in the air. It becomes possible to supply the powder pw that will be produced while preventing its oxidation.

  In addition, in a vacuum environment or a reduced pressure environment, the moisture in the container is reduced, that is, the humidity is lowered, and the powder is easily charged with static electricity and easily adheres to the transport surface 20 of the trough 2. In the present embodiment, as the charging means 6X for charging the powder pw, means such as a vacuum pump 62 for providing the inside of the container 6 in a vacuum environment or a reduced pressure environment is provided. When 20 is covered with the powder pw, the powder pw moving by vibration does not directly contact the trough 2, and the conveyed powder pw is scraped by the trough 2 and damaged or the trough 2 itself is worn. Can be suppressed.

  As mentioned above, although embodiment of this invention was described based on drawing, it should be thought that a specific structure is not limited to these embodiment. The scope of the present invention is shown not only by the above description of the embodiments but also by the scope of claims for patent, and further includes all modifications within the meaning and scope equivalent to the scope of claims for patent.

  For example, in this embodiment, the dam portion 9 is provided along a direction orthogonal to the predetermined transport direction X, but may be provided along a direction intersecting the transport direction X. Moreover, in this embodiment, although the groove | channel 21 is formed along the conveyance direction X from the middle part between the dam part 9 and the downstream end 2a to the downstream end 2a, from the dam part 9 to the downstream end 2a You may form along the conveyance direction X. FIG. Moreover, in this embodiment, although the groove | channel 21 is formed in the cross-sectional U shape, you may be formed in the upward U-shape or other shapes. Moreover, although the groove | channel 21 is formed along the conveyance direction X, it is not limited to this.

  The specific configuration of each part is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 1 ... Hopper 2 ... Trough 2a ... Downstream end 20 ... Conveying surface 21 ... Groove 3 ... Excitation means (electromagnetic drive part)
40 ... Light emitting part 41 ... Optical sensor 42 ... Flow rate detection part 5 ... Vibration control part 6 ... Container 6X ... Charging means 9 ... Weir part pw ... Powder w1 ... Groove width X ... Conveyance direction X1 ... Downstream side X2 ... Upstream side

Claims (5)

The trough that receives the supply of powder from the hopper is vibrated by the vibrating means, whereby the powder on the trough transport surface is moved along a predetermined transport direction and dropped from the downstream end of the trough to be supplied to A powder supply device for supplying to
A projecting shape standing from the conveying surface in a direction intersecting the predetermined conveying direction is formed, and a part of the powder supplied from the hopper and directed to the downstream end is blocked by vibration of the trough. A weir,
A light emitting unit that projects the powder falling from the downstream end via the weir unit and the downstream end, and a light sensor that receives the light irradiated from the light emitting unit and reflected by the powder pw;
A flow rate detector for detecting the amount of powder falling from the downstream end based on the amount of light received by the photosensor;
A vibration control unit for controlling vibrations to be vibrated by the vibration means so that a conveyance speed of the powder having a detection value per unit time by the flow rate detection unit as a target flow rate can be obtained. Powder supply device.   The conveying surface is formed with a plurality of grooves that are set to a groove width that allows passage of a single powder and that extend from the downstream end toward the upstream side along the downstream end, The powder supply apparatus according to claim 1, wherein the protruding direction of the powder guided by the groove is set so as to face the same direction in plan view in all the grooves.   3. The powder supply apparatus according to claim 1, wherein the vibration angle is set such that the powder conveyance speed increases from the upstream side toward the downstream side of the conveyance surface.   The powder supply apparatus according to any one of claims 1 to 3, further comprising a storage container for storing at least the hopper and the trough, wherein the storage container is set in a vacuum environment or a reduced pressure environment filled with an inert gas. .   The powder supply apparatus according to claim 1, further comprising a charging unit configured to charge the powder or the transport surface.

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