JP2012230065A - Weighing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a weighing device that can reduce a weighing time even when a large amount of objects to be weighed are supplied.SOLUTION: A weighing device includes: a weighing hopper 1 that temporarily holds objects to be weighed, supplied by being fallen from above, and then discharges the objects downward; load cells LC1-LC4 that support the weighing hopper 1 in a suspend manner; weight calculation means that calculates the weight of the objects to be weighed in the weighing hopper 1 on the basis of output signals of the load cells LC1-LC4; and a support mechanism 21 that has a supported part 31 fixed to the outer wall of the weighing hopper 1 and a support part 30 for supporting the supported part 31 from below and is formed so that it can switch between a state where the support part 30 supports the supported part 31 from below and a state where the support part 30 is away from the supported part 31 by moving the support part 30.

Description

  The present invention relates to a weighing device that measures an object to be weighed such as powder (detergent, fertilizer, etc.) and granules (resin pellets, grain, feed, etc.) and supplies it to a bag or the like.

  Conventionally, there is a weighing device called a packer scale as a device for filling an object to be weighed made of powder or granules into a container such as a bag (for example, see Patent Document 1).

  In such a weighing device, an object to be weighed is supplied from above to a weighing hopper supported by the load cell, and the weight of the object to be weighed is weighed. The weighing object is supplied to the weighing hopper by discharging the weighing object from a supply device disposed above the weighing hopper. The object to be weighed discharged from the supply device falls by its own weight and is supplied to the weighing hopper. The controller of the weighing device calculates the weight of the weighing object in the weighing hopper based on the output signal of the load cell after a predetermined time (tw) has elapsed after the weighing object is discharged from the supply device. . Here, the predetermined time tw is a time required for the output signal of the load cell to be stabilized, that is, a measurement stabilization waiting time.

  In order to shorten this weighing stabilization waiting time, the technique of Patent Document 1 is provided with a weighing hopper fixing means for clamping the side wall of the weighing hopper from both sides to suppress self-vibration of the weighing hopper due to an impact when the object to be weighed is dropped. It is configured to do.

JP 2004-271350 A

  However, since the technique of Patent Document 1 has a configuration in which the side wall of the weighing hopper is clamped from both sides, that is, a configuration in which the weighing hopper is clamped from the horizontal direction, the impact force of the object to be weighed falling from the top to the bottom is absorbed. Not suitable for. In particular, when weighing large quantities (large weight) of objects to be weighed, the effect of suppressing the self-vibration of the weighing hopper due to the impact when the objects to be weighed falls is reduced, and the effect of shortening the measurement stabilization waiting time and measuring time is also reduced. It will be small. Here, the weighing time is the sum of the weighing stabilization waiting time and the weight calculation time immediately after the weighing stabilization waiting time has elapsed. The weight calculation time is a time required for calculating the weight of the object to be weighed in the weighing hopper based on the output signal of the load cell immediately after the measurement stabilization waiting time elapses. This time is very short, and most of the weighing time is occupied by the weighing stabilization wait time.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a weighing device that can shorten the weighing time even when a large amount (large weight) of an object to be weighed is supplied. It is said.

  In order to achieve the above-mentioned object, a weighing device according to an aspect of the present invention includes a weighing hopper that temporarily holds an object to be weighed dropped from above and then discharges it downward, and the weighing hopper A load cell for hanging and supporting, weight calculating means for calculating the weight of an object to be weighed in the weighing hopper based on an output signal of the load cell, a supported portion fixed to an outer wall of the weighing hopper, A support unit for supporting the support unit from below, and moving the support unit, the support unit supports the supported unit from below; and the support unit is separated from the supported unit. And a support mechanism portion configured to be switchable between the two states.

  According to this configuration, for example, while the object to be weighed is being supplied to the weighing hopper, the supporting part of the lower support mechanism unit supports the supported part fixed to the weighing hopper from below, so that the object to be weighed is It is possible to effectively suppress the vibration of the weighing hopper due to the impact when falling, and to shorten the time required for stabilizing the output signal of the load cell (measurement stabilization waiting time). Therefore, even when a large amount of objects to be weighed are supplied to the weighing hopper at once, the weighing stabilization waiting time can be suppressed to a short time, and the weighing time can be shortened.

  The weighing hopper may have a hanging portion that is fixed to an outer wall of the weighing hopper and is suspended from the load cell, and the supported portion may be fixed directly below the hanging portion.

  According to this configuration, the supported portion is provided directly below the suspension portion suspended from the load cell, and the supported portion directly below the suspension portion is supported from below by the support portion of the support mechanism portion. It is possible to effectively suppress the vibration of the weighing hopper due to the impact when the weighing object is dropped, and to further shorten the weighing stabilization waiting time.

  In addition, the lower support mechanism portion is disposed horizontally, a rotation shaft that performs normal rotation and reverse rotation at a predetermined angle, and is fixed to the rotation shaft, and the rotation shaft rotates forward and reverse at the predetermined angle, An arm portion that rotates between a first rotation position and a second rotation position; a first connecting member having one end rotatably attached to an end portion of the arm portion; A second connecting member rotatably attached to the other end of the first connecting member, and is rotatably supported in parallel with the rotation shaft at a predetermined position, and is connected to the other end of the second connecting member; A fixed horizontal shaft, and a third connecting member having one end fixed to the horizontal shaft and the other end fixed to the support portion, and the arm portion is at the first rotation position. Further, the support portion supports the supported portion from below, and the axis of the rotation shaft is the first connection. It is comprised so that it may be in the state located on the extension line which connects the said one end and the other end of material, and when the said arm part is the said 2nd rotation position, the said support part has left | separated from the said supported part You may be comprised so that it may be in a state.

  According to this configuration, when the support portion is in a state of supporting the supported portion from below, the axis of the rotation shaft is positioned on an extension line connecting one end and the other end of the first connecting member. Therefore, the impact force applied to the support portion when the object to be weighed falls to the weighing hopper does not work in the direction of rotating the arm portion via the first connecting member. Therefore, the holding of the state in which the support portion supports the supported portion becomes strong.

  Further, the weighing hopper is supported by being suspended by the four load cells, and has the four suspension portions that are suspended by the respective load cells. The four suspension portions are square apexes in plan view. The four support mechanisms are fixed to the outer wall of the weighing hopper so as to be positioned at each other, and the supported parts are fixed directly below the suspension parts, and support the supported parts. Among these, the two support mechanism portions corresponding to the two supported portions fixed immediately below the two suspension portions located at both ends of one side of the square form the first support mechanism portion pair. The two lower support mechanisms corresponding to the two supported parts configured and fixed immediately below the two hanging parts located at both ends of the other side opposite to the one side are the second lower support mechanisms. A first pair and a first pair Each of the support mechanism pairs of the two is horizontally disposed, a rotation shaft that performs forward rotation and reverse rotation at a predetermined angle, a center portion is fixed to the rotation shaft, and the rotation shaft is rotated at the predetermined angle forward rotation and reverse rotation. By doing so, an arm portion that rotates between the first rotation position and the second rotation position, and a first connecting member that is rotatably attached to one end portion of the arm portion. A second coupling member having one end pivotably attached to the other end of the first coupling member, and being supported in a first predetermined position so as to be pivotable in parallel with the rotation shaft; A first horizontal shaft fixed to the other end of the connecting member, a third connecting member having one end fixed to the first horizontal shaft and the other end fixed to the support, and one end A fourth connecting member rotatably attached to the other end of the arm, and one end of the fourth connecting member A fifth connecting member rotatably attached to the other end of the first member, and is rotatably supported in a second predetermined position in parallel with the rotation shaft and fixed to the other end of the fifth connecting member. A second horizontal shaft, and a sixth connecting member having one end fixed to the second horizontal shaft and the other end fixed to the support portion. In the moving position, the support portion supports the supported portion from below, and the axis of the rotation shaft is located on an extension line connecting the one end and the other end of the first connecting member. And the fourth connecting member is configured to be positioned on an extension line connecting the one end and the other end, and when the arm portion is in the second rotation position, the support portion is You may be comprised so that it may be in the state away from the supported part.

  According to this configuration, when the support portion supports the supported portion from below, the axis of the rotation shaft is located on the extension line connecting the one end and the other end of the first connecting member, and the fourth Since it is configured to be located on an extended line connecting one end and the other end of the connecting member, the impact force applied to the support portion when the object to be weighed falls to the weighing hopper is the first and fourth. It does not work in the direction of trying to rotate the arm through the connecting member. Therefore, the holding of the state in which the support portion supports the supported portion becomes strong.

  Further, the first horizontal shaft of the first support mechanism portion pair and the first horizontal shaft of the second support mechanism portion pair are integrated with a first common horizontal shaft, The second horizontal shaft of the first support mechanism pair and the second horizontal shaft of the second support mechanism pair may be configured as a second common horizontal shaft integrated with each other. Good.

  As described above, the first and second horizontal shafts of the first support mechanism pair and the first and second horizontal shafts of the second support mechanism pair are integrated with each other. By using the common horizontal axis, the configuration is simplified.

  In addition, when the supported portion and the support portion have a concave portion and the other has a convex portion that is fitted into the concave portion, and the support portion supports the supported portion, When the concave portion and the convex portion face each other in the vertical direction so that the convex portion is fitted in the concave portion, and the support portion is separated from the supported portion, the concave portion and the convex portion May be configured to be in a separated state.

  According to this configuration, since the convex portion is fitted in the concave portion when the support portion supports the supported portion, it is easy to suppress horizontal vibration of the weighing hopper.

  Moreover, each surface of the said convex part and the said recessed part may be comprised by the conical surface or the hemispherical surface.

  According to this structure, since the surface of the convex part and the concave part is formed with a curved surface, the support part and the supported part are easily fitted.

  In addition, the support mechanism unit may be configured to perform a predetermined period of time after the supply of the objects to be weighed to the weighing hopper is completed after the start of the supply of the objects to be weighed to the weighing hopper. The supporting part is in a state of supporting the supported part, and after the predetermined time has elapsed, the supporting part is separated from the supported part, and then the weight calculating means calculates the weight of the object to be weighed in the weighing hopper. It may be configured to calculate.

  According to this configuration, the support portion supports the supported portion from the time before the start of the supply of the weighing object to the weighing hopper until the predetermined time elapses after the supply is completed. Thus, not only when the object to be weighed is dropped, but also the vibration of the weighing hopper after dropping can be suppressed, and the weighing stabilization waiting time can be further shortened.

  In addition, a supply device that supplies the weighing hopper by dropping the object to be weighed is disposed above the weighing hopper, and the support mechanism is configured to supply the object to be weighed to the weighing hopper by the supply device. From the time before the start of the time until the predetermined time elapses after the supply of the object to be weighed to the weighing hopper by the supply device, the support part is in a state of supporting the supported part, After the predetermined time has elapsed, the support portion may be separated from the supported portion, and then the weight calculating unit may be configured to calculate the weight of the object to be weighed in the weighing hopper.

  According to this configuration, the support portion supports the supported portion from the time before the start of the supply of the object to be weighed from the supply device to the weighing hopper until the predetermined time elapses after the supply is completed. By doing so, not only when the object to be weighed is dropped, but also the vibration of the weighing hopper after dropping can be suppressed, and the weighing stabilization waiting time can be further shortened.

  The present invention has the configuration described above, and has an effect that it is possible to provide a weighing device that can shorten the weighing time even when a large amount (large weight) of an object to be weighed is supplied.

(A) is the schematic schematic diagram which looked at the measuring device of the example of 1 composition of an embodiment of the present invention from the front, (b) is the schematic schematic diagram which looked at the measuring device from the side, (c ) Is a schematic plan view of the main part of the weighing device as viewed from above. (A) is a figure which shows the state of the support mechanism part when supporting the weighing hopper under support, (b) is a figure which shows the state of the support mechanism part when not supporting the measurement hopper. (C) is a figure which shows the modification of a support mechanism part. It is a block diagram which shows the outline of the control system of the weighing | measuring apparatus of embodiment of this invention. It is a timing chart which shows an example of operation of a measuring device of an embodiment of the present invention.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. In the following description, the same or corresponding elements are denoted by the same reference symbols throughout all the drawings, and redundant description thereof is omitted. Further, the present invention is not limited to the following embodiment.

(Embodiment)
Fig.1 (a) is the schematic schematic diagram which looked at the weighing | measuring device of the one structural example of embodiment of this invention from the front, FIG.1 (b) is the schematic schematic diagram which looked at the same weighing device from the side. is there. Moreover, FIG.1 (c) is the schematic plan view which looked at the principal part of the weighing | measuring device from upper direction. In the following, for convenience of explanation, “front”, “back”, “left”, and “right” are determined as shown in FIG. 1C, for example. The same reference numerals are given to components having equivalent functions arranged in the front-rear or left-right direction (some symbols are omitted).

  This weighing device includes a weighing hopper 1, four load cells LC 1, LC 2, LC 3, LC 4 that suspend and support the weighing hopper 1, and an object fixed immediately below the hanging portion 17 of the weighing hopper 1 at a predetermined timing. A support mechanism portion 21 that receives and supports the support portion 31 from below with the support portion 30 and a controller 2 (see FIG. 3) are provided. The load cells LC1 to LC4 are fixed to the gantry 19 of the weighing device by appropriate fixing means.

  In this weighing device, a supply device 61 for supplying an object to be weighed to the weighing hopper 1 as shown by a two-dot chain line in FIG. In this example, the supply device 61 is also included in the weighing device, but is not limited thereto. The supply device 61 includes a cylindrical chute 62 made of a cylinder to which an object to be weighed is supplied from above, and a pair of cut gates 63c and 63d that open and close the opening at the lower end of the cylindrical chute 62. . The cut gates 63c and 63d are arranged so that the lower end opening of the downstream chute 11 can be opened and closed. The cut gates 63c and 63d are fixed to the horizontal shafts 63a and 63b, and the horizontal shafts 63a and 63b are opened and closed by rotating, for example, using the driving force of an AC servomotor (not shown). Is configured to do. That is, the cut gates 63c and 63d are opened by rotating in the directions of the arrows c and d, respectively, and in this state, the objects to be weighed in the cylindrical chute 62 are discharged, and the weighing hopper 1 Supplied to. In addition, the cut gates 63c and 63d are in a closed state (shown) by being rotated from the open state in the direction opposite to the arrows c and d, respectively.

  Also, below the weighing hopper 1, for example, a funnel (not shown) for receiving an object to be weighed discharged from the weighing hopper 1 and supplying it to a packaging machine (not shown) is disposed. .

  The weighing hopper 1 includes a rectangular hopper body 11, a pair of discharge gates 12a and 12b for opening and closing an opening at the lower end of the hopper body 11, and a rotary actuator 13 for opening and closing the discharge gates 12a and 12b. Have.

  In the hopper body 11, the mounting plate connecting portion 14 is fixed to the outside of the front and rear side walls by appropriate fixing means, and the mounting plate 15 is fixed to each mounting plate connecting portion 14 by appropriate fixing means. An L-shaped mounting plate 16 is fixed to 15. The L-shaped mounting plate 16 has a horizontal surface portion 16a and a vertical surface portion 16b, and the vertical surface portion 16b is fixed to the mounting plate 15 by, for example, welding.

  Here, a structure for attaching the discharge gates 12a and 12b to the hopper body 11 will be described. The discharge gates 12a and 12b are respectively fixed to the left and right shafts 41 by appropriate fixing means, and are connected to the rotary actuator 13 via a link portion using a known toggle mechanism. Each of the left and right shafts 41 is attached to the front and rear mounting plates 15 so as to be rotatable about its axis. As described above, the mounting plate 15 is fixed to the hopper body 11 via the mounting plate connecting portion 14. The rotary actuator 13 is fixed to the mounting plate 15. When the rotary shaft 13a of the rotary actuator 13 rotates, for example, counterclockwise, each shaft 41 rotates through the link portion, and thereby the discharge gates 12a and 12b rotate in the directions of arrows a and b. Thus, the discharge gates 12a and 12b are opened. When the discharge gates 12a and 12b are closed, the reverse operation is performed. The driving of the rotary actuator 13 is controlled by the controller 2.

  Next, the hopper body 11 is suspended and supported by the four load cells LC1 to LC4. This support structure will be described. The suspension support structure of the hopper body 11 by the load cells LC1 to LC4 is the same.

  As shown in FIG. 1C, the four load cells LC <b> 1 to LC <b> 4 are arranged in the vicinity of the outer sides of the four corners of the rectangular hopper body 11 in a plan view. A suspension member 18 is attached to one end of each load cell LC1 to LC4. The upper portion of the suspension portion 17 is hooked in a through hole (not shown) provided in the suspension member 18. The lower portion of the suspension portion 17 passes through a through hole provided in the L-shaped mounting plate 16 and is fixed to the horizontal surface portion 16a of the L-shaped mounting plate 16 by appropriate fixing means such as a nut. As described above, the L-shaped attachment plate 16 is fixed to the hopper body 11 via the attachment plate 15 and the attachment plate connecting portion 14. As a result, the hopper body 11 is supported by being suspended by the four load cells LC1 to LC4. In addition, although the suspension part 17 is comprised with the hook member here, this is an example and is not restricted to this.

  Next, the lower support mechanism portion 21 will be described. FIG. 2A is a view showing a state of the support mechanism portion 21 when the weighing hopper 1 is supported and supported, and FIG. 2B is a support mechanism when the weighing hopper 1 is not supported. It is a figure which shows the state of the part. Here, regarding the L-shaped mounting plate 16, only the horizontal surface portion 16a is illustrated, and the vertical surface portion 16b is not illustrated.

  In the present embodiment, a supported portion 31 having a conical convex portion protruding downward is fixed to the lower end of each suspension portion 17 corresponding to each load cell LC1 to LC4. That is, the hanging portion 17 and the supported portion 31 are fixed to the outside of the side wall of the hopper body 11 (outer wall of the weighing hopper 1) via the L-shaped attachment plate 16, the attachment plate 15, and the attachment plate connecting portion 14.

  Here, as shown in FIGS. 2A and 2B, the support mechanism 21 on the load cell LC1 side and the load cell LC2 side will be described. However, the support mechanism 21 on the load cell LC3 side and the load cell LC4 side is also on the load cell LC1 side. And it is the structure similar to the support mechanism part 21 of the load cell LC2 side.

  Each of the support mechanism portions 21 on the load cell LC1 side and the load cell LC2 side includes a support portion 30 having a concave portion into which the convex portion of the supported portion 31 is fitted, a shared rotary actuator 22, a rotary actuator 22, and a support portion 30. And a plurality of members (23 to 29) for connecting the two. The rotary actuator 22 is fixed to a horizontal plate 51 (see FIGS. 1A and 1B) by a plurality of attachment members 32. Instead of the rotary actuator 22, a stepping motor may be used.

  The plurality of members (23 to 29) will be described. The central portion of the arm portion 23 is fixed to the rotary shaft 22 a of the rotary actuator 22. One end of a connecting rod 24 is rotatably attached to each end of the arm 23. The upper end of the connecting member 25 is rotatably attached to the other end of the connecting rod 24. A pair of sandwiching members 26 that sandwich a horizontal rotation shaft (horizontal shaft) 27 by, for example, bolts (not shown) are fixed to the lower end of the connecting member 25. The horizontal rotation shaft 27 is rotatably supported at a predetermined position by a bearing 33 attached to the vertical plate 52, for example, as shown in FIG. The horizontal rotation shaft 27 is supported in parallel with the rotation shaft 22 a of the rotary actuator 22. With the above configuration, when the rotating shaft 22a rotates and the arm portion 23 rotates, the horizontal rotating shaft 27 rotates.

  In addition, a pair of clamping members 28 that clamp the horizontal rotation shaft 27 by, for example, bolts (not shown), for example, are fixed to the connecting plate 29 on one end, and on the other end. The support part 30 is fixed by appropriate fixing means. Thereby, when the horizontal rotation shaft 27 rotates, the support portion 30 rotates about the axis. Note that the pair of clamping members 28 fixed to the connecting plate 29 have the same size as the pair of clamping members 26 described above, but in FIG. Yes. As shown in FIG. 1C, the pair of sandwiching members 28 and the pair of sandwiching members 26 are different from each other in the front-rear direction at the position where the horizontal rotation shaft 27 is sandwiched.

  In the state shown in FIG. 2A, the lower support mechanism portion 21 is in a state in which the support portion 30 supports the supported portion 31 from below, and at this time, the arm portion 23 and the left and right connecting rods 24 are supported. Are arranged in a straight line passing through the axis of the rotating shaft 22a. When an object to be weighed is put into the weighing hopper 1 in this state, a large impact force is applied to the L-shaped mounting plate 16 in the downward direction. It is added in the direction of g, that is, in the direction toward the axis of the rotating shaft 22a. That is, since the force to rotate the rotating shaft 22a is not applied, it is easy to maintain the state shown in FIG.

  From the state shown in FIG. 2A, when the rotary shaft 22a of the rotary actuator 22 rotates by a predetermined angle (θ) in the direction of arrow e, the horizontal rotary shaft 27 rotates and is supported around the axis of the horizontal rotary shaft 27. As shown in FIG. 2B, the part 30 is rotated, and the support part 30 is separated from the supported part 31. In this state, the support mechanism unit 21 does not affect the outputs of the load cells LC1 and LC2. Therefore, when the support mechanism 21 on the load cell LC3 side and the load cell LC4 side is also in the same state as in FIG. 2B, the weight of the object to be weighed in the hopper body 11 is based on the output signals of the load cells LC1 to LC4. Can be calculated.

  2B, when the rotary shaft 22a of the rotary actuator 22 rotates by a predetermined angle (θ) in the direction opposite to the arrow e (direction of the arrow h) from the state shown in FIG. 2B, the state shown in FIG. Become.

  In each of the support mechanism portions 21 on the load cell LC1 side and the load cell LC2 side, the connecting rod 24 corresponds to the first connecting member, and the connecting member 25 and the pair of clamping members 26 correspond to the second connecting member. The connecting plate 29 and the pair of clamping members 28 correspond to the third connecting member. The arm portion 23 includes an arm portion (an arm portion that connects the rotating shaft 22a and the left connecting rod 24 in FIG. 2A) in the support mechanism portion 21 on the load cell LC1 side, and a support mechanism portion on the load cell LC2 side. The arm portion 21 (the arm portion that connects the rotating shaft 22a and the right connecting rod 24 in FIG. 2A) is integrated, and the rotary actuator 22 is supported by the load cell LC1 side. It is shared by the mechanism part 21 and the support mechanism part 21 on the load cell LC2 side.

  The support mechanism portions 21 on the load cell LC3 side and the load cell LC4 side also have the same configuration as described above.

  Note that the support mechanism portion 21 on the load cell LCn (n = 1 to 4) side is a support mechanism portion 21 having a support portion 30 for supporting the supported portion 31 directly below the suspension portion 17 corresponding to the load cell LCn. That is.

  Further, in the present embodiment, corresponding to the four load cells LC <b> 1 to LC <b> 4, four suspension parts 17 are provided so as to be positioned at the vertices of the square in a plan view, and supported under the respective suspension parts 17. The part 31 is also provided so as to be located at the vertex of the square. Then, four support mechanism portions 21 having a support portion 30 for supporting each supported portion 31 are provided. Of these, the support mechanism 21 on the load cell LC1 side and the support mechanism 21 on the load cell LC2 constitute a first support mechanism pair, and the support mechanism 21 on the load cell LC3 and the support mechanism on the load cell LC4. 21 can be said to constitute a second support mechanism pair. In this case, in each of the first and second support mechanism portion pairs, the connecting rod 24 in one support mechanism portion 21 corresponds to the first connecting member, and the connecting member 25 and the pair of clamping members 26 are the first. Corresponding to the second connecting member, the connecting plate 29 and the pair of clamping members 28 correspond to the third connecting member, and the connecting rod 24 in the other lower support mechanism portion 21 corresponds to the fourth connecting member, The connecting member 25 and the pair of holding members 26 correspond to the fifth connecting member, and the connecting plate 29 and the pair of holding members 28 correspond to the sixth connecting member. The left and right horizontal rotation shafts 27 are formed by integrating the two horizontal shafts in the support mechanism pair of the load cells LC1 and LC2 and the two horizontal shafts in the support mechanism pair of the load cells LC3 and LC4. This corresponds to the first and second common horizontal axes.

  In the present embodiment, the support mechanism portion 21 supporting the weighing hopper 1 supports the supported portion 31 fixed to the measurement hopper 1 from below by the support portion 30 of the support mechanism portion 21. That is.

  FIG. 3 is a block diagram illustrating an outline of a control system of the weighing device according to the present embodiment.

  The controller 2 is configured by, for example, a microcontroller and has a CPU and memories such as a RAM and a ROM. In the controller 2, the CPU executes the execution program stored in the memory, thereby controlling the present weighing device including the supply device 61 and also functions as a weight calculation unit. The controller 2 may be configured by a single control device that performs centralized control, or may be configured by a plurality of control devices that perform distributed control in cooperation with each other.

  The controller 2 receives output signals from the load cells LC1 to LC4 that support the weighing hopper 1 through a known signal processing circuit (amplifier, A / D converter, etc .; not shown), Based on this, the controller 2 calculates the weight of the object to be weighed held by the weighing hopper 1. Here, it goes without saying that the total value of the values indicated by the output signals of the four load cells LC <b> 1 to LC <b> 4 corresponds to the weight of the object to be weighed held in the weighing hopper 1.

  The controller 2 controls the open / close operation of the cut gates 63c and 63d by controlling, for example, an AC servo motor via a drive circuit (not shown) (ie, controlling the supply device 61). Further, the opening / closing operation of the discharge gates 12a and 12b is controlled by controlling the rotary actuator 13 through a drive circuit (not shown). For example, the controller 2 opens the cut gates 63c and 63d for a first predetermined time set in advance and discharges the objects to be weighed from the supply device 61, and then, based on the output signals of the load cells LC1 to LC4. After calculating the weight of the object to be weighed in the weighing hopper 1, at a predetermined timing (for example, when a discharge permission signal is input from the packaging machine), the discharge gates 12a and 12b for a preset second predetermined time. Is opened, and the object to be weighed is discharged from the weighing hopper 1. The discharged objects to be weighed are supplied to the packaging machine through the above-described funnel, for example.

  Further, the controller 2 moves back and forth via a drive circuit (not shown) so that the four support mechanism portions 21 provided corresponding to the load cells LC1 to LC4 perform the same operation at the same timing. The two rotary actuators 22 are controlled.

  Next, the operation of the weighing device of this embodiment will be described with reference to FIG. FIG. 4 is a timing chart showing an example of the operation of the weighing device of the present embodiment.

  In FIG. 4, a period Ts is a period corresponding to one operation cycle of the weighing device. The discharge period T1 of the supply device 61 is a period in which the cut gates 63c and 63d of the supply device 61 are open, and the objects to be weighed are discharged from the supply device 61 to the weighing hopper 1 during this period. During periods other than this discharge period T1, the cut gates 63c and 63d are in a closed state.

  The weighing period T2 is a period required for weighing (weight measurement) of the objects to be weighed in the weighing hopper 1, and is necessary for the output signals of the load cells LC1 to LC4 to be stabilized after the objects to be weighed are supplied to the weighing hopper 1. It consists of time (measurement stabilization waiting time) and time (weight calculation time) required to calculate the weight of the object to be weighed based on the output signals of the load cells LC1 to LC4 immediately after the measurement stabilization waiting time. Since the weight calculation time is extremely short, most of the time during the measurement period T2 is occupied by the measurement stabilization waiting time. Here, the measurement stabilization waiting time is, for example, a preset time, and is measured immediately after the discharge period T1 of the supply device 61 ends.

  The discharge period T3 of the weighing hopper 1 is a period in which the discharge gates 12a and 12b of the weighing hopper 1 are open, and the objects to be weighed are discharged from the weighing hopper 1 during this period. During the period other than the discharge period T3, the discharge gates 12a and 12b are closed.

  The support period T4 is a period during which the support mechanism portion 21 supports and supports the weighing hopper 1, and during this period, the support mechanism portion 21 is in the state shown in FIG. During a period other than the support period T4, the support mechanism 21 is in the state shown in FIG. 2B, and does not support and support the weighing hopper 1.

  In the controller 2, for example, between time t2 and t3, the cut gates 63c and 63d are opened and the objects to be weighed are discharged from the supply device 61 to the weighing hopper 1, and then waiting for the weighing stabilization waiting time to elapse. The weight of the object to be weighed in the weighing hopper 1 is calculated on the basis of the output signals of the load cells LC1 to LC4 immediately after (weighing period T2). Thereafter, the discharge gates 12a and 12b of the weighing hopper 1 are opened at time t5, and the objects to be weighed are discharged from the weighing hopper 1. Immediately thereafter (time t6), the support mechanism 21 is brought into a support state to support and support the weighing hopper 1, and then, at time t7, discharge of the object to be weighed from the supply device 61 is started, and the weighing hopper 1 Start feeding the sample.

  Further, the controller 2 starts immediately after the discharge of the object to be weighed by the weighing hopper 1 (for example, at time t1), or when the supply of the next object to be weighed to the weighing hopper 1 ends (the discharge of the object to be weighed by the supply device 61 ends). The weighing hopper 1 is supported and supported by the support mechanism 21 until a predetermined time (for example, the time between time t3 and t4) elapses (for example, between time t1 and t4).

  As described above, in the weighing device, when continuous operation is performed, the operation in one operation cycle (Ts) is repeatedly performed.

  Here, the support mechanism 21 is configured to support and support the weighing hopper 1 immediately after the discharge of the object to be weighed by the weighing hopper 1, but the weighing is performed after the discharge of the object to be weighed by the weighing hopper 1 is completed. The weighing hopper 1 may be supported and supported immediately before the supply of the next object to be weighed to the hopper 1 is started.

  In the present embodiment, since the weighing hopper 1 is supported by and supported by the lower support mechanism portion 21 over the entire discharge period T1 of the object to be weighed from the supply device 61 to the weighing hopper 1, the impact when the object to be weighed falls. The vibration of the weighing hopper 1 due to the above can be suppressed, and the time required for stabilizing the output signals of the load cells LC1 to LC4 (measurement stabilization waiting time) can be shortened. Therefore, even if a large amount of objects to be weighed at a time is supplied from the supply device 61 to the weighing hopper 1, the weighing stabilization waiting time can be suppressed to a short time, and the weighing time (time required for the weighing period T2) can be shortened. It is also possible to shorten the time of one operation cycle (Ts) of the weighing device.

  Further, during a predetermined time following the discharge period T1 of the supply device 61 (for example, the time between time t3 and t4 in FIG. 4), the weighing hopper 1 is supported and supported by the supporting mechanism unit 21, thereby The vibration of the weighing hopper 1 due to the impact at the time of dropping can be further suppressed, and the waiting time for weighing stability can be further shortened.

  In addition, immediately after the discharge period T3 of the weighing hopper 1, the weighing hopper 1 is supported by the lower support mechanism portion 21 to suppress the vibration of the weighing hopper 1 due to the opening / closing operation of the discharge gates 12a and 12b of the weighing hopper 1. Yes. Thereby, it is possible to suppress an increase in vibration of the weighing hopper 1 when an object to be weighed is supplied to the weighing hopper 1 immediately thereafter.

  Moreover, in this embodiment, since the support mechanism part 21 is supporting from the downward | lower direction of the suspension part 17 suspended by the load cells LC1-LC4 via the suspension member 18, when the to-be-measured item falls It is possible to effectively suppress the vibration of the weighing hopper 1 due to the impact, and to shorten the waiting time for weighing. As described above, it is preferable to support the portion directly below the suspension portion 17 from below, but the configuration is not limited to this.

  Further, when the lower support mechanism portion 21 supports and supports the weighing hopper 1, the arm portion 23 and the connecting rod 24 are configured to be aligned on a straight line passing through the axis of the rotation shaft 22a. The impact force applied to the support portion 30 when the object to be weighed falls to the weighing hopper 1 is propagated in the direction indicated by the arrows f and g in the connecting rod 24 and does not work in the direction in which the arm portion 23 is to be rotated. . Therefore, the holding of the state in which the support portion 30 supports the supported portion 31 is strengthened. This effect is that when the lower support mechanism portion 21 supports and supports the weighing hopper 1, the axis of the rotary shaft 22 a is connected to one end of the connecting rod 24 to which the arm portion 23 is attached and to the connection member 25. It is obtained by being located on an extension line connecting the other end of the rod 24 and that the connecting rod 24 has a rod shape (linear shape).

[Modification of support mechanism]
FIG.2 (c) is a figure which shows the modification of a support mechanism part. The lower support mechanism portion 21x includes a support portion 30 having a concave portion into which the convex portion of the supported portion 31 is fitted, and a jig cylinder 45 that moves the support portion 30 in the vertical direction. The jig cylinder 45 is fixed to a gantry not shown. The jig cylinder 45 may be fixed to the mount 19 (FIG. 1A) to which the load cells LC1 to LC4 are fixed via an attachment member, for example. Here, the support mechanism portion 21x on the load cell LC1 side will be described, but the support mechanisms on the other load cells LC2 to LC4 have the same configuration and perform the same operation at the same timing.

  The operation of the jig cylinder 45 is controlled by the controller 2 (see FIG. 3). FIG. 2C shows the state of the support mechanism portion 21x when the weighing hopper 1 is not supported and supported. When the weighing hopper 1 is supported and supported, the jig cylinder 45 moves the rod forward, thereby supporting the support portion 30. The supported portion 31 is configured to fit into the support portion 30.

  In the lower support mechanism portions 21 and 21x in the present embodiment including the above-described modified examples, the support portion 30 has a concave shape, the supported portion 31 has a convex shape, and the convex portion of the supported portion 31 becomes a concave portion of the support portion 30. By fitting, it becomes easy to suppress the horizontal vibration of the weighing hopper 1. Instead of the concave shape of the support portion 30 and the convex shape of the supported portion 31 being conical (the contact surface is a conical surface), for example, a hemisphere (the contact surface is a hemispheric surface), a truncated cone shape, a pyramid shape ( The contact surface may be a pyramid surface), a truncated pyramid shape, or the shape of the smaller curved surface when the spherical surface is divided into two planes that do not pass through the center. However, a curved surface such as a conical shape or a hemispherical shape is preferable to the support portion 30 and the supported portion 31 rather than a pyramid shape or a truncated pyramid shape.

  Moreover, although the support part 30 is made into the recessed part and the to-be-supported part 31 is made into the convex part, on the contrary, the support part 30 may be made into a convex part and the to-be-supported part 31 may be made into a recessed part. What is necessary is just to make the shape of a convex part and a recessed part the same as the above-mentioned, for example.

  In the present embodiment, the load hopper 1 is suspended and supported at four points using the four load cells LC1 to LC4. However, the present invention is not limited to this. For example, the weighing hopper 1 may be suspended and supported at a plurality of points (two points, three points, etc.) using a plurality of load cells (two or three, etc.). In this case as well, it is preferable to provide the support mechanism portion corresponding to the supported portion provided directly below the suspension portion suspended from each load cell, but this is not restrictive. In short, if the supported portion is fixed to the outer wall of the weighing hopper 1 and has a supporting portion for supporting the supported portion from below, vibration of the weighing hopper 1 due to an impact when the object to be weighed is dropped. It becomes possible to suppress.

  In some cases, when the object to be weighed is discharged from the weighing hopper 1, the weighing hopper 1 can be supported by the lower support mechanism.

  INDUSTRIAL APPLICABILITY The present invention is useful as a weighing device that can measure a large amount of objects to be measured and can shorten the measurement time.

LC1 to LC4 Load cell 1 Weighing hopper 2 Controller 17 Suspension part 18 Suspension member 21, 21x Lower support mechanism part 31 Supported part 30 Support part 22 Rotary actuator 22a Rotating shaft 23 Arm part 24 Connecting rod 25 Connecting member 26 Holding member 27 Horizontal Rotating shaft 28 Holding member 29 Connecting plate 30 Supporting portion 31 Supported portion 45 Jig cylinder 61 Supply device

Claims (9)

A weighing hopper that temporarily drops the object to be weighed supplied from below and then discharges it downward;
A load cell for hanging and supporting the weighing hopper;
Weight calculating means for calculating the weight of the object to be weighed in the weighing hopper based on the output signal of the load cell;
A supported portion fixed to the outer wall of the weighing hopper;
A support portion for supporting the supported portion from below, and moving the support portion so that the support portion supports the supported portion from below; and the support portion is the supported portion. A supporting device configured to be able to switch between a state away from the weighing device and a weighing device. The weighing hopper has a hanging portion fixed to the outer wall of the weighing hopper and suspended from the load cell,
The weighing device according to claim 1, wherein the supported portion is fixed immediately below the hanging portion. The support mechanism is
A rotating shaft that is disposed horizontally and that performs forward rotation and reverse rotation at a predetermined angle;
An arm that is fixed to the rotation shaft and rotates between the first rotation position and the second rotation position by the normal rotation and reverse rotation of the rotation shaft by the predetermined angle;
A first connecting member having one end rotatably attached to an end of the arm portion;
A second connecting member having one end pivotably attached to the other end of the first connecting member;
A horizontal shaft that is supported in a predetermined position in parallel with the rotation shaft and rotatably, and is fixed to the other end of the second connecting member;
A third connection member having one end fixed to the horizontal shaft and the other end fixed to the support;
When the arm portion is in the first rotation position, the support portion supports the supported portion from below, and the axis of the rotating shaft is connected to the one end of the first connecting member and the other It is configured to be in a state of being located on an extension line connecting the ends,
When the arm portion is in the second rotation position, the support portion is configured to be separated from the supported portion.
The weighing device according to claim 1. The weighing hopper is supported by being suspended by the four load cells, and has the four suspension portions that are suspended by the load cells. The four suspension portions are positioned at the apexes of a square in plan view. And is fixed to the outer wall of the weighing hopper, and the supported parts are fixed directly below each of the suspension parts,
Of the four support mechanism parts for supporting each of the supported parts,
The two lower support mechanism portions corresponding to the two supported portions fixed directly below the two suspension portions located at both ends of one side of the square form a first lower support mechanism portion pair,
The two lower support mechanism portions corresponding to the two supported portions fixed immediately below the two suspension portions located at both ends of the other side opposite to the one side form a second lower support mechanism portion pair. Configure
Each of the first and second support mechanism pairs is:
A rotating shaft that is disposed horizontally and that performs forward rotation and reverse rotation at a predetermined angle;
An arm that rotates between a first rotation position and a second rotation position by having a central portion fixed to the rotation shaft and the rotation shaft rotating forward and reverse by a predetermined angle;
A first connecting member having one end rotatably attached to one end of the arm portion;
A second connecting member having one end pivotably attached to the other end of the first connecting member;
A first horizontal shaft that is supported in a first predetermined position so as to be rotatable in parallel with the rotation shaft and fixed to the other end of the second connecting member;
A third connecting member having one end fixed to the first horizontal shaft and the other end fixed to the support;
A fourth connecting member having one end rotatably attached to the other end of the arm portion;
A fifth connecting member having one end rotatably attached to the other end of the fourth connecting member;
A second horizontal shaft that is supported in a second predetermined position so as to be rotatable in parallel with the rotation shaft and fixed to the other end of the fifth connecting member;
A sixth connection member having one end fixed to the second horizontal shaft and the other end fixed to the support;
When the arm portion is in the first rotation position, the support portion supports the supported portion from below, and the axis of the rotating shaft is connected to the one end of the first connecting member and the other It is configured to be located on an extension line connecting the ends and on an extension line connecting the one end and the other end of the fourth connecting member,
When the arm portion is in the second rotation position, the support portion is configured to be separated from the supported portion.
The weighing device according to claim 1. The first horizontal shaft of the first support mechanism pair and the first horizontal shaft of the second support mechanism pair are integrated with a first common horizontal shaft.
The second horizontal shaft of the first support mechanism pair and the second horizontal shaft of the second support mechanism pair are configured by a second common horizontal shaft integrated with each other.
The weighing device according to claim 4. The supported part and the support part have a convex part that either one has a concave part and the other is fitted in the concave part,
When the supporting portion is in a state of supporting the supported portion, the concave portion and the convex portion are in a vertical direction and the convex portion is fitted in the concave portion,
When the support portion is away from the supported portion, the concave portion and the convex portion are configured to be in a separated state.
The weighing device according to claim 1.   The weighing device according to claim 6, wherein each surface of the convex portion and the concave portion is configured by a conical surface or a hemispherical surface.   The support mechanism is configured to support the support unit from a point in time before the start of the supply of the object to be weighed to the weighing hopper until a predetermined time elapses after the supply of the object to be weighed to the weighing hopper is completed. Is in a state in which the supported portion is supported, the support portion is separated from the supported portion after the predetermined time has elapsed, and then the weight calculating means calculates the weight of the object to be weighed in the weighing hopper. The weighing device according to claim 1, configured as described above. A supply device for supplying the weighing hopper by dropping an object to be weighed is disposed above the weighing hopper,
The support mechanism is configured so that a predetermined time elapses after the supply device finishes supplying the weighing hopper to the weighing hopper from the time before the supply device starts supplying the weighing hopper to the weighing hopper. Until the support portion supports the supported portion, and after the predetermined time has elapsed, the support portion is separated from the supported portion. After that, the weight calculating means in the weighing hopper The weighing device according to claim 1, wherein the weighing device is configured to calculate a weight of an object to be weighed.

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