JP2012237603A - Combination balance - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a combination balance capable of enhancing the combination accuracy without giving damage to an article to be measured which is frangible by a fall-off shock or the like.SOLUTION: A belt conveyer is segmented so that the upper area of a turning endless conveyer belt has plural holding areas 1A and 1B having a predetermined length in a turning direction. The combination balance comprises: plural weighing conveyers 1 each of which receives an article to be measured, which is supplied by hand on the holding areas 1A and 1B; a collective conveyor 3 that conveys articles to be measured and discharges the same to the outside from the weighing conveyor 1; plural weight sensors 2 that measure the weight of the article on the weighing conveyor 1; and a controller 5 that controls the weighing conveyor 1 to perform the conveyance operation to calculate weight of articles on each of the holding area based on the value measured by the weight sensor 2, determines a combination of holding areas so that total weight of the measured articles is within a target weight range and discharges the measured articles from the holding areas selected as a combination.

Description

  The present invention relates to a combination weigher for obtaining a combination in which the total weight of objects to be weighed is within a predetermined target weight range.

  Combination weighers can be broadly classified into automatic, semi-automatic, and manual types depending on the method of supplying and discharging the objects to be weighed to the weighing unit. In the manual combination weigher, the objects to be weighed are supplied and discharged manually. In the semi-automatic combination weigher, the object to be weighed is supplied manually, and the object to be weighed is automatically discharged (for example, see Patent Document 1). Moreover, in an automatic combination weigher, supply and discharge | emission of a to-be-measured item are performed automatically (machine control) (for example, refer patent document 2).

  A manual or semi-automatic combination weigher is used for an object that cannot be automatically supplied to the combination weigher or an object that is not suitable for automatic operation.

  In a conventional semi-automatic combination weigher, for example, a plurality of hoppers are arranged in a straight line, and one belt conveyor is arranged therebelow. When the operator supplies the object to be weighed to the hopper, the weight of the object to be weighed is weighed, the discharge gate of the hopper selected for the combination whose combination weight is within the predetermined weight range is opened and closed, and the object to be weighed is discharged. The object to be weighed discharged from the hopper is conveyed in one direction by a belt conveyor and discharged to a subsequent apparatus such as a packaging machine.

JP 2006-214784 A No. 7-33139

  In the conventional semi-automatic combination weigher, the objects to be weighed are discharged from the hopper selected for the combination onto the belt conveyor and conveyed. However, the belt conveyor conveys the objects to be weighed in the direction in which the hoppers are arranged. The hopper is arranged at a position considerably higher than the belt conveyor so that the object to be weighed does not come into contact with the hopper. Therefore, the impact when the object to be weighed falls from the hopper onto the belt conveyor is large, and is not suitable for weighing an object to be weighed that is easily broken or damaged. For example, if an object to be weighed such as mushrooms having a bulk portion is dropped from the hopper onto the belt conveyor, the bulk portion is easily damaged, and the commercial value is lowered or the product cannot be sold as a product.

  Also, the operator must pay attention not to let the object to be weighed into the discharge gate of the hopper, and an unskilled worker, etc., mistakes the timing of supplying the object to be weighed to the hopper. This may cause problems such as causing the object to be weighed into the discharge gate of the hopper. In order to handle a conventional semi-automatic combination weigher, training and habituation of an operator are required.

  Further, in the combination weigher, it is important to improve the combination accuracy (measurement accuracy) so that the discharged weight for each time approaches the target weight as much as possible.

  The present invention has been made in order to solve the above-described problems, and does not damage even an object to be weighed that is fragile or easily damaged by an impact at the time of dropping, etc., and has a combination accuracy (measurement accuracy). It aims at providing the combination scale which can aim at improvement of.

  In order to achieve the above object, a combination weigher according to an aspect of the present invention has an endless conveyor belt that circulates, and a region on the upper side of the conveyor belt has a predetermined length n in the circulation direction. A belt conveyor that is divided so as to have a plurality of holding areas (n is a plurality) and can be intermittently conveyed with the predetermined length as a unit of a conveying distance, and the object to be manually fed is held in the holding area A plurality of weighing conveyors that are transported on one end and discharged from one end, and a conveyance conveyor that is supplied with the objects to be weighed discharged from each of the weighing conveyors, conveys the objects to be weighed and discharges them to the outside, A plurality of weight sensors, each of which is provided corresponding to the weighing conveyor and measures the weight of an object to be weighed supplied on the weighing conveyor, and each of the holding regions based on the measured value of the weight sensor In A weight calculating means for calculating the weight of the object to be weighed, and a combining means for obtaining a discharge combination consisting of a combination of the holding regions in which the total weight of the objects to be weighed is within a target weight range; Weighing conveyor control means for transporting the weighing conveyor so as to discharge the objects to be weighed in the holding area selected for the discharge combination.

  According to this configuration, since a plurality of holding areas are provided for each weighing conveyor, a plurality of weight values used for combination processing (combination calculation) can be obtained for each weighing conveyor. That is, the number of weight values used for the combination calculation increases, and the combination accuracy can be improved.

  In addition, the weighing conveyor that transports the object to be weighed to the weighing unit that measures the weight of the object to be weighed, and the object to be weighed discharged from the weighing conveyor can be discharged to the outside by the conveyor. The level difference with the conveyor can be reduced, and the impact when the object to be weighed discharged from the weighing conveyor is transferred onto the conveyor is reduced. Therefore, even an object to be weighed that is easily broken or damaged by an impact at the time of dropping can be measured and discharged without being damaged. Also, since the work to supply the objects to be weighed is simply placed on the weighing conveyor, even an unskilled operator can easily perform the work compared to the case of supplying to the hopper like a conventional combination weigher. Can do.

  In addition, the combination means performs a first process for obtaining the discharge combination consisting of only the holding region located at the foremost position in the transport direction in each of the weighing conveyors, and as a result of the first process, When there is no combination that falls within the target weight range and the discharge combination is not obtained, the holding area that is not located at the foremost position in the transport direction on the weighing conveyor and all the holding areas that are in front of the holding area May be configured to perform a second process for obtaining the discharge combination including the combination including

  According to this configuration, the first process for obtaining a discharge combination including a combination of only the holding regions positioned at the foremost is performed preferentially. Therefore, when the combination process is repeatedly performed by repeating only the first process, the combination process (combination calculation) can always be performed using the number of weight values corresponding to the number of weighing conveyors. That is, by performing combination processing at short time intervals, productivity can be improved without causing a decrease in combination accuracy. Further, the occurrence of a combination failure can be reduced by performing the second process. In addition, the weighing conveyor is configured by a single drive system. In the combination process, the weighing conveyor is used when only the first process is performed and when both the first process and the second process are performed. The operation of the weighing conveyor can be easily switched simply by changing the transport distance. Further, in the case where only the first process is performed and in the case where both the first process and the second process are performed, the conveyance time of the weighing conveyor is made the same by changing the conveyance speed of the weighing conveyor. Can be done, and work efficiency is not reduced.

  Moreover, it may be configured to manually supply an object to be measured only to the holding region located at the rearmost side in the transport direction of the weighing conveyor.

  According to this configuration, in each weighing conveyor, the objects to be weighed are supplied only to the holding area located at the rearmost side. Therefore, when the weight value of the weight sensor increases, the increase amount is the most rearward. The weight calculating means can recognize that the weight is the weight of the object to be weighed supplied to the holding region located on the side. Therefore, there is no need for detection means for detecting which holding area the object to be weighed is supplied to.

  Moreover, you may further provide the to-be-measured object detection means which detects that the to-be-measured object is supplied with respect to each said holding | maintenance area | region.

  According to this configuration, since the weighing object detection means is provided in each holding area, when the weight value of the weight sensor increases, the increase amount is supplied to the holding area detected by the weighing object detection means. The weight calculating means can recognize that the weight is the weight of the measured object. In this case, the operator can supply the objects to be weighed to any holding area.

  In the weighing conveyor, the surface area of the conveyor belt is divided into m divided areas (m is an integer of 4 or more) of the predetermined length in the circumferential direction, and is positioned on the upper side of the conveyor belt. The divided area may be configured to coincide with the holding area.

  In this case, the number (m) of the divided areas may be an odd number, but by using an even number, the entire area on the upper side of the conveyor belt is used as a holding area, and m / 2 pieces are obtained. A holding area can be provided, and the length of the conveyor can be used effectively.

  The conveyor belt may be provided with a crosspiece on the boundary between the divided regions adjacent to each other.

  According to this configuration, by providing a crosspiece on the boundary between one divided region and the other divided region adjacent to each other, even if an object to be weighed that is easy to roll is placed on the holding region, it rolls to the next holding region. It can be prevented from moving.

  In addition, the plurality of weighing conveyors constitute first and second weighing conveyor groups arranged with the conveyance conveyor interposed therebetween, and each of the first and second weighing conveyor groups constitutes each of them. The weighing conveyors are arranged in parallel, and each of the weighing conveyors of the first and second weighing conveyor groups has the conveying conveyor positioned on the one end side so that the conveying direction intersects with the conveying conveyor. It may be arranged.

  According to this configuration, by arranging the weighing conveyor groups on both sides of the transfer conveyor, the length of the transfer conveyor can be shortened, the discharge time of the objects to be weighed can be shortened, and the combination scale can be made compact. In addition, since the combination weigher can be made compact, it is easy for the operator to perform the work of supplying the objects to be weighed.

  The present invention has the above-described configuration, and does not damage even an object to be weighed that is easily broken or damaged by an impact at the time of dropping, etc., and improves the combination accuracy (measurement accuracy). It is possible to provide a combination weigher capable of

(A) is the schematic plan view which looked at the combination weigher of the one structural example of embodiment of this invention from the top, (b) is the schematic schematic diagram which looked at the combination weigher from the side. It is a block diagram which shows schematic structure of the combination weigher of the example of 1 structure of embodiment of this invention. (A), (b) is a flowchart which shows an example of operation | movement of the combination weigher of the example of 1 structure of embodiment of this invention. It is a schematic plan view which shows a part of combination weigher of the other structural example of embodiment of this 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. Moreover, the numerical value illustrated below (for example, the number of the measurement parts Cw etc.) is an example, and is not limited to the numerical value.

(Embodiment)
FIG. 1A is a schematic plan view of a combination weigher according to an embodiment of the present invention as viewed from above, and FIG. 1B is a schematic diagram of the combination weigh as viewed from the side. FIG. 2 is a block diagram showing a schematic configuration of a combination weigher of one configuration example of the embodiment of the present invention.

  This combination weigher includes a plurality of (for example, 12) weighing units Cw, a collective conveyor 3, an operation indicator 4, a control unit 5, and the like.

  Here, in FIG. 1A, the collective conveyor 3 is disposed between the six weighing units Cw on the right side in the drawing and the six weighing units Cw on the left side. The weighing conveyors 1 of the six weighing units Cw on the right side are arranged in parallel on one side of the collective conveyor 3, and the respective conveying directions (directions of arrows a) are the conveying directions of the collective conveyor 3 (indicated by arrows c). Direction) and intersect (in this example, orthogonal). Further, the weighing conveyors 1 of the six weighing units Cw on the left side are arranged in parallel on the other side of the collective conveyor 3, and their respective conveying directions (directions of arrows b) intersect with the conveying direction of the collective conveyor 3. (It is orthogonal in this example).

  Each weighing unit Cw includes a weighing conveyor 1 and a weight sensor 2 that measures the weight of the object P to be weighed on the weighing conveyor 1. The weight sensor 2 includes a load cell that supports the weighing conveyor 1 including the drive motor 1M. The drive motor 1M is composed of, for example, a stepping motor.

  Each weighing conveyor 1 is constituted by a belt conveyor, and a surface area serving as a conveying surface of the ring-shaped endless belt (conveyor belt) is equally divided into four sections having a predetermined length (L) in the circumferential direction. , It has four divided regions D consisting of each section. And the crosspiece 21 is provided on the boundary of the division area D adjacent to each other. That is, four crosspieces 21 are provided on the surface of the belt at equal intervals.

  Further, the upper region of the belt is divided into two regions having a predetermined length (L) in the circumferential direction, the region on the front side in the transport direction is defined as the front holding region 1A, and the region on the rear side in the transport direction is defined as the rear holding region 1B. It is said. The two divided areas D positioned on the upper side of the belt are configured to coincide with the front holding area 1A and the rear holding area 1B, respectively.

  Each weighing conveyor 1 has a length L in the circumferential direction of each holding area 1A, 1B (in other words, a length L in the circumferential direction of each divided area D) as a unit of the conveyance distance, and the conveyance direction (circulation) of arrows a and b. Direction) can be intermittently moved. That is, the horizontal conveyance distance by one conveyance operation is a distance that is an integral multiple of the length L of each holding region such as L and 2L.

  The collective conveyer 3 is a conveyer configured by a belt conveyer, and conveys the objects to be weighed P in the direction of an arrow c, for example. Then, for example, a post-stage device (not shown) is installed at the transport destination, and the objects to be weighed P transported by the collective conveyor 3 are supplied to the post-stage device.

  And the collective conveyor 3 etc. except the some measurement part Cw and both ends are accommodated in the apparatus main body part 22 which consists of a housing | casing. Further, the apparatus main body portion 22 is provided with an opening 22 a serving as a supply port for the object to be weighed P at an upper portion of the rear holding area 1 </ b> B of the weighing conveyor 1. The workpiece P is supplied from the opening 22a to the rear holding region 1B by the operator.

  Further, the apparatus main body unit 22 also stores the conveyor drive circuit units 8a and 8b and the A / D conversion unit 9 shown in FIG.

  Further, the weight sensor 2 supporting each weighing conveyor 1 measures the weight of the object P on the weighing conveyor 1, and the measured value (analog weight signal) is converted into a digital signal by the A / D converter 9. To the control unit 5.

  The control unit 5 is configured by, for example, a microcontroller, and includes an arithmetic control unit 6 including a CPU and a storage unit 7 including a memory such as a RAM and a ROM. The storage unit 7 stores an operation program, operation parameter data, measurement data, and the like. The control unit 5 functions as weight calculation means, combination means, weighing conveyor control means, collective conveyor control means, and the like. The control unit 5 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 control unit 5 executes the operation program stored in the storage unit 7 by the arithmetic control unit 6, thereby performing overall control of the combination weigher and performing combination processing described later. For example, a measured value measured by the weight sensor 2 to which each weighing conveyor 1 is attached is acquired as a digital value through the A / D conversion unit 9 as needed, and stored in the storage unit 7 if necessary. Further, the driving operation of each weighing conveyor 1 is controlled via the conveyor driving circuit unit 8a, and the driving operation of the collective conveyor 3 is controlled via the conveyor driving circuit unit 8b. Further, a discharge command signal is input from a subsequent apparatus (not shown) via the I / O circuit unit 10 and a discharge completion signal is output to the subsequent apparatus. In addition, a signal is input from the operation display 4 and a signal such as data to be displayed on the operation display 4 is output.

  The operation indicator 4 includes, for example, a touch screen type display (display device). On the screen of the display, the operation of the combination weigher can be started and stopped, operation parameters can be set, and the like. The result of combination processing (combination weight, etc.) by the control unit 5 can be displayed on the display screen.

  An example of the operation of the combination weigher of the configuration example of the present embodiment configured as described above will be described. FIGS. 3A and 3B are flowcharts showing an example of the operation of the combination weigher according to one configuration example of the present embodiment. The operation of this combination weigher is realized by the processing of the control unit 5. It should be noted that all information necessary for controlling the operation of the combination weigher is stored in the storage unit 7. The object to be weighed P is, for example, an agricultural product or the like. An example is mushrooms such as eringi. In the following description, the symbol P indicating the object to be weighed may be omitted.

  The operator performs an operation of supplying (loading), for example, the objects to be weighed P one by one to the rear holding area 1B of the weighing conveyor 1 when the weighing conveyor 1 is in the transport stop state. Although not shown, the control unit 5 acquires the measurement value of each weight sensor 2 from the A / D conversion unit 9 at regular time intervals, and a new object to be weighed is supplied based on the measurement value of the weight sensor 2. The weighing conveyor 1 is recognized and the weight value of the object to be weighed supplied to the weighing conveyor 1 is recognized and stored.

  Here, when recognizing the weighing conveyor 1 to which the object to be weighed is newly supplied, when the weighing value increases, the amount of increase in the weighing value and a preset load detection reference value (for example, 6 g) And when it is less than the loading detection reference value, it is determined that a new weighing object is supplied. judge. The loading detection reference value is set in advance in the control unit 5 and stored in the storage unit 7.

  FIG. 3A is a flowchart showing an example of the operation of the combination weigher regarding an arbitrary weighing unit Cw. In the following description, the weight value of the holding area 1A (1B) is the weight value of the object placed on the holding area 1A (1B).

  For example, when it is determined in step S1 that the object to be weighed is newly supplied as described above, the amount of increase in the measured value is set to the weight of the object to be newly supplied, and the weight value is set to the rear holding region 1B. Is stored in the storage unit 7 as a weight value (step S2). For example, a weight value table for storing the weights of the objects to be weighed in the rear holding area 1B and the front holding area 1A of each weighing conveyor 1 is created in the storage unit 7. The weight values of the objects to be weighed are stored in this weight value table, and the initial values of all the weight values are set to zero. Here, since the objects to be weighed are supplied to the rear holding area 1B in each weighing conveyor 1, first, the weight Wn of the newly supplied objects to be weighed is the weight of the rear holding area 1B of the corresponding weighing conveyor 1. Stored as a value.

  Then, it is determined whether or not an object to be weighed is placed on the front holding area 1A of the weighing conveyor 1 (step S3). This determination is made based on whether or not the weight value of the front holding area 1A of the weighing conveyor 1 in the weight value table is zero.

  When an object to be weighed is not placed on the front holding area 1A, that is, when the weight value of the front holding area 1A of the weight value table is 0, the length L of each holding area is transferred by the weighing conveyor 1 by the transport distance. And the object to be weighed in the rear holding area 1B is conveyed to the front holding area 1A (step S4). Then, the weight value of the front holding area 1A in the weight value table is changed to the weight Wn, and the weight value of the rear holding area 1B is reset to 0 (step S5).

  The above processing is performed every time an object to be weighed is newly supplied to an arbitrary weighing conveyor 1. Therefore, all the weights of the objects to be weighed P that are placed on the holding areas 1A and 1B and whose weighing values are fixed are stored in the weight value table.

  Here, the combination process by the control unit 5 will be described. In this combination processing, a combination calculation is performed based on the weight of the object P stored in the weight value table of the storage unit 7, and the total weight of the object to be weighed from the holding areas 1 </ b> A and 1 </ b> B of the weighing conveyor 1. One combination in which (combination weight) falls within the target weight range (allowable range for the combination target weight) is determined and determined as the discharge combination. Here, the case where the rear holding area 1B of a certain weighing conveyor 1 is selected as the discharge combination is limited to the case where the front holding area 1A of the same weighing conveyor 1 is also selected as the same discharge combination.

  An example of this combination process will be described. This example combination process includes a first process and a second process. First, in the first process, a combination calculation is performed using only the weight of the objects to be weighed in the front holding area 1A of the weighing conveyor 1, and one combination of the front holding area 1A in which the combined weight falls within the target weight range is obtained. And decide on a combination. When there are a plurality of such discharge combination candidates (combinations), for example, the combination having the smallest absolute value of the difference between the combination weight and the combination target weight is determined as the discharge combination. Here, if there is a combination whose combination weight falls within the target weight range, the combination process is terminated without performing the second process described later.

  In the first process described above, the second process is performed only when there is no combination whose combined weight falls within the target weight range. In the second process, the combination calculation is performed using the weights of the objects to be weighed in the front holding area 1A and the rear holding area 1B. When the rear holding area 1B of a certain weighing conveyor 1 is selected as the discharge combination, the combination weight is within the target weight range on the condition that the front holding area 1A of the weighing conveyor 1 is also selected as the same discharge combination. One combination of the holding areas 1A and 1B that are inside is obtained and determined as a discharge combination. When there are a plurality of such discharge combination candidates (combinations), for example, the combination having the smallest absolute value of the difference between the combination weight and the combination target weight is determined as the discharge combination.

  The objects to be weighed on the holding areas 1A and 1B selected as the discharge combination are transported by the weighing conveyor 1 having the holding areas 1A and 1B and discharged onto the collective conveyor 3. Here, for the weighing conveyor 1 in which only the front holding area 1A is selected as the discharge combination, the control unit 5 performs the conveying operation with the length L of each holding area as the conveying distance, and is stored in the weight value table. The weight value of the front holding area 1A of the weighing conveyor 1 is discarded, and the weight value of the rear holding area 1B immediately before (before the transfer operation) is newly stored as the weight value of the front holding area 1A, and the rear holding area Reset the weight value of 1B to zero. In addition, the weighing conveyor 1 in which both holding areas 1A and 1B are selected as the discharge combination is transported with a length (2L) twice as long as the length L of each holding area as a transport distance, and is stored in the weight value table. The stored weight values of the front holding area 1A and the rear holding area 1B of the weighing conveyor 1 are discarded and reset to zero. As described above, when the weighing conveyor 1 whose holding area is selected as the discharge combination is driven, the weight value in the weight value table is updated.

  Next, an example of the repetitive operation of the combination weigher will be described with reference to FIG.

  When the discharge command signal is input from the subsequent apparatus in step S11, the control unit 5 proceeds to the process of step S12, performs the above-described combination process, and obtains the discharge combination. Next, in step S13, the weighing conveyor 1 having the holding areas 1A and 1B selected as the discharge combination is driven as described above to convey the objects to be weighed on the weighing conveyor 1 to the collective conveyor 3. Then, the collective conveyor 3 is driven for a predetermined time, and the objects to be weighed conveyed from the weighing conveyor 1 are conveyed to the subsequent apparatus. Then, the weight value in the weight table relating to the driven weighing conveyor 1 is updated as described above (step S14), and a discharge completion signal is output to the subsequent apparatus at a predetermined timing (step S15). The above operation is repeated.

  The latter apparatus is configured to output a discharge command signal to the combination weigher at a predetermined timing and start a predetermined operation when a discharge completion signal from the combination weigher is input. As the latter stage device, for example, a bag-feeding type packaging machine for bagging an object to be weighed may be arranged. In addition, as a rear-stage apparatus, for example, an apparatus (intermittent conveyance apparatus) that intermittently horizontally moves a plurality of trays (shallow boxes) connected in a ring shape may be arranged. In this case, the objects to be weighed discharged from the collective conveyor 3 are supplied to the tray of the intermittent conveyance device. The objects to be weighed supplied to each tray are further packed in one pack by the next stage apparatus or operator. In this case, for example, the intermittent transport device outputs a discharge command signal to the combination weigher when the tray is moved and an empty tray is moved to the discharge port of the collective conveyor 3, and a discharge completion signal is input from the combination weigher. Then, the tray is moved after a predetermined time has elapsed, and the next empty tray is moved to the discharge port of the collective conveyor 3.

  In the present embodiment, since a plurality of holding areas 1A and 1B are provided for each weighing conveyor 1, a plurality of weight values used for combination calculation can be obtained for each weighing conveyor 1. That is, the number of weight values used for the combination calculation increases, and the combination accuracy can be improved.

  In the present embodiment, in the combination process, for example, a first process for obtaining a discharge combination consisting of only the front holding region 1A is performed, and only when a discharge combination is not obtained in the first process, both The second process for obtaining a discharge combination including a combination including the holding areas 1A and 1B is performed. That is, when the combination process is repeatedly performed only by the first process, the combination calculation can always be performed using the number of weight values corresponding to the number of the weighing conveyors 1. For example, when combination processing is performed at short time intervals, for example, when the current combination processing is being performed, it is possible to newly supply an object to be weighed to the rear holding region 1B and perform weighing. In addition, the weight values of all the front holding regions 1A (weight values corresponding to the number of the weighing conveyors 1) can be used, and the combination accuracy can be improved. For example, in the case where the holding area of the weighing conveyor is not divided into a plurality, only one object to be weighed can be placed on one weighing conveyor, and only after the object to be weighed is discharged. It is not possible to supply new objects to be weighed. In this case, if the combination process is performed at short time intervals, the next time the combination process is performed, the weight of the object to be weighed supplied to the weighing conveyor that has just discharged the object to be weighed has not been measured. It cannot be used for the calculation, and the combination accuracy is greatly reduced. On the other hand, in this embodiment, since each weighing conveyor 1 is configured so that objects to be weighed a plurality of times can be placed, performing combination processing at short time intervals reduces the combination accuracy. Productivity can be improved without incurring.

  Further, when the combination process is repeatedly performed by repeating only the first process, the objects to be weighed in the rear holding area 1B are not directly discharged without stopping in the front holding area 1A. The discharge time of the object to be weighed from can be made constant, and the discharge time is not prolonged. Further, when the discharge combination is not obtained in the first process, the frequency of the combination failure can be reduced by performing the second process and obtaining the discharge combination. In addition, the weighing conveyor 1 is configured by a single drive system, and in the combination process, when only the first process is performed, and when both the first process and the second process are performed, the weighing is performed. The operation of the weighing conveyor 1 can be easily switched only by changing the transport distance of the conveyor 1. Furthermore, when only the first process is performed and when both the first process and the second process are performed, by changing the transport speed of the weighing conveyor 1, the transport time of the weighing conveyor is the same, for example. Work efficiency is not reduced. That is, the conveying speed (V1) of the weighing conveyor 1 in which both the holding areas 1A and 1B are selected as the discharging combination, and the conveying speed (V2) of the weighing conveyor 1 in which only the front holding area 1A is selected as the discharging combination. You can do it faster. For example, if the conveyance speed (V1) is twice the conveyance speed (V2), the conveyance time can be made the same.

  As described above, in this embodiment, it is possible to realize both improvement in combination accuracy and improvement in productivity.

  The combination process is not limited to the above example. Another example will be described. In another example of the combination processing, combination calculation is performed using the weights of the objects to be weighed in the front holding area 1A and the rear holding area 1B of all the weighing conveyors 1, and the combination weight is within the target weight range. One combination having the smallest absolute value of the difference between the weight and the combination target weight is obtained and determined as the discharge combination. However, when the rear holding area 1B of a certain weighing conveyor 1 is selected as the discharge combination, it is a condition that the front holding area 1A of the weighing conveyor 1 is also selected as the same discharge combination. According to this combination processing, all combinations that can be discharged are obtained, and the discharge combination is determined from the combinations as described above, so that the combination accuracy can be further improved.

  Further, in the present embodiment, the combination accuracy can be improved as described above. However, in the unlikely event that a combination failure occurs in which there is no combination within the target weight range, the control unit 5 should be replaced. An object to be weighed may be determined, and the weighing conveyor 1 on which the object to be weighed is placed may be informed to the operator by an informing means. Any notification means may be used as long as it can notify the worker. For example, the indicator lamp 23 (refer FIG. 1 (a), (b)) corresponding to each weighing conveyor 1 is provided one by one, and the weighing object to be replaced is placed under the control of the control unit 5. You may comprise so that the indicator lamp 23 corresponding to the conveyor 1 may be lighted or blinked. In the case of the present embodiment, the replacement work is performed on the objects to be weighed in the rear holding region 1B through the opening 22a.

  Various methods for determining the objects to be weighed can be considered. For example, as a first determination method, an average weight of objects to be weighed placed in each holding area is calculated, and a predetermined number of objects to be weighed with a large difference (difference) from this average weight are given priority ( For example, about 1 to 2). When the selected object to be weighed is placed on the rear holding area 1B, the object to be weighed is determined to be replaced. Further, when the selected object to be weighed is placed on the front holding area 1A and the object to be weighed is not placed on the rear holding area 1B, the weighing conveyor 1 on which the selected object to be weighed is placed. The workpiece is reversely conveyed by the length L of the holding area, and the selected object is transferred to the rear holding area 1B. Further, when the selected object to be weighed is placed on the front holding area 1A and the object to be weighed is placed on the rear holding area 1B, for example, Therefore, the weighing object having the largest difference from the average weight may be selected, and the weighing object may be determined as the weighing object to be replaced.

  Further, as a second determination method, the average weight of the objects placed on each holding area is calculated, and the difference (difference) from the above average weight among the objects placed on the rear holding area 1B. It is also possible to select a predetermined number (for example, about 1 to 2) of objects to be weighed with a large weight value, and determine the objects to be weighed to be replaced.

  Further, in the present embodiment, the configuration is such that the operator supplies the objects to be weighed to the weighing conveyors 1 only to the rearmost holding area 1B. You may comprise so that an operator can supply a to-be-measured item to all the holding | maintenance area | regions 1A and 1B of the conveyor 1. FIG. In this case, an object detection means comprising, for example, a photoelectric sensor for detecting that an object to be weighed is supplied (placed) to each holding area 1A, 1B of each weighing conveyor 1 is provided. The detection signal from the object detection means is output to the control unit 5. As a result, the control unit 5 recognizes the weight value (and the weighing conveyor 1) of the object to be newly supplied by the amount of increase in the measurement value of the weight sensor 2, and detects the weight value by the detection signal from the object detection unit. Since it is possible to recognize whether the object to be weighed has been supplied to the holding areas 1A and 1B, for example, a weight value table can be created and combined processing can be performed.

  In this case, if a combination failure occurs in the combination process, the operator can easily replace the objects to be weighed. In this case, the determination of the object to be weighed may be performed based on the operator's judgment. Further, the control unit 5 calculates the average weight of the objects to be weighed placed in each holding area, and gives priority to the objects to be weighed having a large difference (difference) from the average weight (for example, 1). It is also possible to select the object to be weighed and replace it, and notify the operator of the holding areas 1A and 1B on which the object is placed by the notifying means. Any notification means may be used as long as it can notify the worker. For example, an indicator lamp corresponding to each holding area 1A, 1B of each weighing conveyor 1 is provided, and the indicator lamp corresponding to the holding area 1A, 1B on which an object to be replaced is placed is turned on under the control of the control unit 5. Or you may comprise so that it may blink.

  Moreover, in one structural example of this embodiment, the area | region of the upper side of the belt of the weighing conveyor 1 is equally divided into two in the circumference direction, and two holding areas 1A and 1B are provided, and the surface area of the belt is arranged in the circumference direction. Although four divided areas D are equally divided into four sections, the present invention is not limited to this. For example, if two or more holding regions having a predetermined length L are provided in the upper region of the belt of the weighing conveyor 1 and four or more divided regions having a predetermined length L are provided in the surface region of the belt. Good. For example, a configuration with two holding areas and five divided areas is possible. In this case, each of the two holding areas is not an area obtained by dividing the upper area of the belt into two equal parts.

  For example, as shown in FIG. 4, the area on the upper side of the belt of each weighing conveyor 1 is equally divided into three, the area on the front side in the conveying direction is set as the front holding area 1 a, and the center area is set as the center holding area 1b, and the rear side area is a rear holding area 1c. Then, the surface area of the belt of each weighing conveyor 1 is equally divided into six divided areas in the circumferential direction so that the three divided areas positioned on the upper side of the belt coincide with the three holding areas 1a, 1b, 1c. It may be configured. In this case, the operator may supply the object to be weighed only from the opening 22a to the rear holding area 1c. Alternatively, as described above, the operator opens all the upper parts of the apparatus main body 22 and each holding area 1a. It is also possible to provide a weighing object detecting means for 1b and 1c so that the weighing objects can be supplied to all the holding areas 1a, 1b and 1c.

  The combination process in this case can also be performed in the same manner as in the above-described configuration example. For example, the weight value of only the front holding region 1a located at the forefront in the transport direction in each weighing conveyor 1 may be used for the combination calculation. In this case, when the discharge combination is not obtained, the weight values of the two holding regions 1a and 1b in the front in the transport direction may be used for the combination calculation. Further, in this case, when no discharge combination is obtained, the weight values of all the holding areas 1a, 1b, and 1c may be used for the combination calculation. Other methods may also be used.

  Moreover, in this embodiment, since the crosspiece 21 is provided on the boundary between the divided areas D adjacent to each other, even if the object to be weighed easily rolls, the object to be weighed placed on each holding area is another holding area. It can be prevented from moving by rolling. In the case of an object to be weighed that does not roll, the crosspiece 21 need not be provided. Further, in the case where the upper part of the apparatus main body 22 is opened without providing the crosspieces 21, in order for an operator to place an object to be weighed, a mark indicating each holding area is provided on the belt or frame of the weighing conveyor 1 or the like. It should be provided. For example, the mark may be a line indicating the boundary between the holding areas. Such a mark is not necessary when the opening 22a is provided. In this case, the opening 22a serves as a mark indicating a holding area for supplying an object to be weighed. In short, in the case of an object to be weighed that does not roll, it is only necessary to have a mark that allows the operator to recognize (view) the holding area to which the object to be weighed is supplied.

  In addition, when the object to be weighed easily rolls, guide plates for preventing the object to be weighed are provided on both sides of the weighing conveyor 1 so that the object to be weighed does not fall from both sides of the weighing conveyor 1. May be.

  Further, in this embodiment, the surface area of the belt of the weighing conveyor 1 is equally divided into four or more divided areas in the circumferential direction. If the mark which can recognize the holding | maintenance area | region which supplies a to-be-measured object is provided, it can also be set as the structure which does not divide the surface area of a belt into a division area. In this case, the plurality of holding regions may not be a region in which the region on the upper side of the belt of the weighing conveyor 1 is equally divided into a plurality. For example, the upper region of the belt of the weighing conveyor 1 includes a plurality of holding regions each having a predetermined length L in the circumferential direction, and the conveyance distance by one conveyance operation of the weighing conveyor 1 is determined as the holding region. It may be configured to perform the transport operation as an integral multiple of the length L (L, 2L, etc.).

  In this embodiment, the weighing conveyor 1 is used for each of the plurality of weighing units Cw for weighing the objects to be weighed, and the objects to be weighed discharged from one end of the weighing conveyor 1 are conveyed by the collective conveyor 3. Therefore, the level difference between the weighing conveyor 1 and the collective conveyor 3 can be reduced, and the impact when the objects to be weighed discharged from the weighing conveyor 1 selected as the discharge combination are transferred onto the collective conveyor 3 can be reduced. Less. Therefore, even an object to be weighed that is easily broken or damaged by an impact when dropped can be measured without being damaged.

  Moreover, in this embodiment, by arrange | positioning the weighing conveyor 1 on both sides of the collective conveyor 3, the length of the collective conveyor 3 can be shortened and the discharge | emission time of a to-be-measured object can be shortened. Further, the combination weigher can be made compact, and the operator can easily perform the operation of supplying the objects to be weighed. In addition, since the work for supplying the objects to be weighed is simply placed on the weighing conveyor 1, even an unskilled worker can easily perform the work compared to the case of supplying the objects to the hopper like a conventional combination weigher. be able to. The weighing conveyor 1 may be arranged only on one side of the collective conveyor 3. However, in this case, the length of the collective conveyor 3 is increased in order to arrange a predetermined number of the weighing conveyors 1 and Since the discharge time of an object also becomes long, when shortening a measurement cycle, it is preferable to arrange | position on both sides as mentioned above.

  In the present embodiment, the combination process is performed when the discharge command signal is input from the subsequent apparatus, but the present invention is not limited to this. For example, when combination processing is performed at a predetermined time interval set in advance and a discharge command signal is input, the weighing conveyor 1 and the collective conveyor 3 whose holding areas are selected as the discharge combination are driven to dispose the objects to be weighed. May be discharged. Further, when a discharge command signal is not input from the rear stage apparatus, or when there is no rear stage apparatus and another worker receives the objects to be weighed discharged from the collective conveyor 3, the predetermined time interval is set in advance. Combination processing may be performed.

  Moreover, you may make it the collective conveyor 3 drive always. If the motor for driving the conveyor is not driven, power is not consumed. However, since extra power is consumed when the motor is started, it is preferable to drive the motor so as to reduce power consumption as a whole.

  INDUSTRIAL APPLICABILITY The present invention is useful as a combination weigher or the like that does not damage even an object to be weighed that is easily broken or damaged by an impact when dropped.

DESCRIPTION OF SYMBOLS 1 Weighing conveyor 2 Weight sensor 3 Collective conveyor 4 Operation indicator 5 Control part 21 Crosspiece 1A, 1B, 1a, 1b, 1c Holding area D Divided area

Claims (7)

It has an endless conveyor belt that circulates, and an upper region of the conveyor belt is divided so as to have n holding areas (n is a plurality) having a predetermined length in the circumferential direction, and conveys the predetermined length. A belt conveyor that can be intermittently transported as a unit of distance, a plurality of weighing conveyors that carry and manually feed the objects to be weighed on the holding area and discharge from one end,
A conveyor to which the objects to be weighed discharged from each of the weighing conveyors are supplied, convey the objects to be weighed, and discharge them to the outside;
A plurality of weight sensors each provided corresponding to the weighing conveyor and measuring the weight of an object to be weighed supplied on the weighing conveyor;
Weight calculating means for calculating the weight of an object to be weighed supplied to each of the holding regions based on the measured value of the weight sensor;
A combination means for obtaining a discharge combination comprising a combination of the holding areas in which the total weight of the objects to be weighed is within a target weight range;
A combination weigher comprising: weighing conveyor control means for conveying the weighing conveyor so as to discharge the objects to be weighed in the holding area selected for the discharge combination. The combination means includes
Performing a first process for obtaining the discharge combination consisting of a combination of only the holding areas located in the foremost direction of conveyance in each of the weighing conveyors;
As a result of the first processing, when there is no combination that falls within the target weight range and the discharge combination is not obtained, the holding area that is not located at the foremost position in the transport direction on the weighing conveyor and the holding area The combination weigher according to claim 1, wherein the combination weigher is configured to perform a second process for obtaining the discharge combination including a combination including all the holding regions in front of the other.   The combination weigher according to claim 1, wherein the weighing object is manually supplied only to the holding region located at the rearmost side in the transport direction of the weighing conveyor.   The combination weigher according to claim 1, further comprising weighing object detection means for detecting that the weighing object is supplied to each of the holding regions. The weighing conveyor is
A surface area of the conveyor belt is divided into m pieces (m is an integer of 4 or more) of the predetermined length in the circumferential direction, and the divided area located on the upper side of the conveyor belt is the holding area. The combination weigher according to claim 1, configured to match.   The combination weigher according to claim 5, wherein the conveyor belt is provided with a crosspiece on a boundary between the divided regions adjacent to each other. The plurality of weighing conveyors constitute first and second weighing conveyor groups arranged with the conveying conveyor interposed therebetween,
In each of the first and second weighing conveyor groups, the weighing conveyors constituting each are arranged in parallel,
The measuring conveyors of each of the first and second measuring conveyor groups are arranged such that the conveying conveyor is located on the one end side and the conveying direction intersects with the conveying conveyor. The combination scale according to any one of the above.

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