JP5495992B2 - Combination weigher and weighing packaging system using the same - Google Patents

Description

  The present invention relates to a combination weigher for weighing an object to be weighed such as confectionery and a weighing packaging system using the combination weigher.

  Conventionally, for example, there is a combination weigher as a weighing device for weighing an object to be weighed such as confectionery. The objects to be weighed with the combination weigher are generally supplied to a packaging machine and packed in a bag. In such a weighing and packaging system, for example, a packaging machine is installed below the combination weigher, and an object to be weighed to a weight within a predetermined weight range by the combination weigher is supplied to the packaging machine.

  In a conventional combination weigher, for example, a plurality of weighing hoppers for measuring the weight of an object to be weighed, and objects to be weighed that are arranged below the weighing hopper and discharged from the weighing hopper are collected and discharged to a packaging machine. And a collective chute. Further, above each weighing hopper, a supply hopper for supplying an object to be weighed to the weighing hopper, a linear feeder for supplying the object to be weighed to the supply hopper, and a distribution for supplying the object to be weighed to each linear feeder are provided. A feeder and the like are provided. In this combination weigher, a combination of weighing hoppers (discharge combination) that combines the weights of the objects to be weighed supplied to a plurality of weighing hoppers into a weight within a predetermined weight range (allowable range with respect to the target weight) by performing a combination calculation. ) And the gate of the weighing hopper selected for the discharge combination is opened and closed, and the objects to be weighed are discharged onto the collecting chute. The objects to be weighed discharged onto the collecting chute are supplied to the packaging machine from the discharge port below the collecting chute.

  In such a combination weigher, in order to perform normal high-speed operation, it is important to set appropriate values such as the gate opening / closing time of the weighing hopper and values for determining the timing. For example, Patent Document 1 describes a configuration in which a gate opening / closing time of a weighing hopper is set based on an average value of a plurality of data obtained in advance by a predetermined number of combined discharge operations.

  In a packaging machine (for example, a vertical pillow packaging machine), an object to be weighed discharged from a combination weigher is received and packaged while manufacturing a bag. In such a packaging machine, for example, a bag having an upper opening is formed while a packaging material fed from a film roll is formed, and an object to be weighed discharged from the combination weigher through the upper opening is put into the bag. The upper opening is sealed and sealed by performing a lateral seal.

  On the other hand, in order to enable the linkage operation between the combination weigher and the packaging machine, signals are exchanged between the combination weigher and the packaging machine. For example, a packaging machine outputs a discharge request signal for requesting discharge of an object to be measured to a combination weigher at a predetermined timing, and the combination weigher notifies the packaging machine of discharge of an object to be measured at a predetermined timing. A discharge completion signal is output. The combination weigher obtains the discharge combination, and if the discharge request signal from the packaging machine is input, discharges the object to be weighed and outputs the discharge completion signal. The packaging machine responds to the discharge completion signal from the combination weigher. Thus, it is configured to perform a lateral seal.

  In such a weighing and packaging system, if the object to be weighed discharged from the combination weigher is sealed in the horizontal direction before it enters one bag of the packaging machine, the object to be weighed is caught in the seal portion. This results in poor bag making (seal failure). The biting in such a packaging machine is caused by the length from the front end (top) to the end (last end) of the object to be discharged from the combination weigher (hereinafter referred to as “the length of the object to be measured”). This is because the time until the object to be weighed falls and completely fits in the bag becomes longer. In order to prevent this biting, if the time interval for performing the horizontal sealing in the packaging machine is increased, the production capacity will be reduced.

  For example, in Patent Document 2, paying attention to the difference in the length of the objects to be weighed depending on the combination of hoppers from which the objects to be weighed are discharged (discharge combination), a weighing object detection sensor is provided at the discharge port of the collecting chute. And calculating the passage time required to pass from the front end to the end of the object to be weighed through the discharge port of the collecting chute, storing the above passage time corresponding to the repeatedly obtained discharge combination, and the packaging machine The above passage time when the object to be weighed in is stored as an unacceptable passage time, and when obtaining the next discharge combination, refer to the passage time stored corresponding to the discharge combination. Thus, a configuration is described in which biting in the packaging machine is prevented by obtaining a discharge combination on condition that the passage time is less than the non-permissible passage time. In addition, if there is no discharge combination that satisfies the above conditions, discharge the object to be weighed with the combination that removes the condition and the total weight of the object to be weighed is within the specified weight range, Biting in the packaging machine is prevented by delaying the timing of outputting the completion signal.

Japanese Patent Laid-Open No. 5-99732 JP 2006-71515 A

  In a combination weigher, depending on the type, amount, or state of an object to be weighed supplied to a linear feeder or the like for supplying an object to be weighed to a weighing hopper, a suddenly large amount (for example, a target weight of 8) (About 10%) may be supplied. For example, in the case of objects to be weighed that are easily entangled with each other, a large amount of objects to be weighed when they are supplied from the linear feeder to the supply hopper drop to the supply hopper, May be supplied to a weighing hopper. However, in the configurations of Patent Documents 1 and 2, it is considered that the above case is not assumed.

  For example, when a very large amount (for example, about 80% of the target weight) of an object is suddenly supplied to a certain weighing hopper, and the weighing hopper is selected as a discharge combination, a predetermined gate set in advance In the opening / closing operation based on the opening / closing time, it is not possible to discharge all of the large amount of objects to be weighed, and there is a case where the objects to be weighed remain in the weighing hopper or the objects to be weighed are stuck in the gate of the hopper. In such a case, an object to be weighed within a predetermined weight range may not be discharged, resulting in erroneous weighing (defective product).

  In the configuration of Patent Document 1, an average value of a plurality of data (a time required from the beginning to the end of the weighing object to pass through the collection chute discharge port) obtained in advance by a predetermined number of combined discharge operations, and the like Since the gate opening / closing time of the weighing hopper is determined based on the above, it is impossible to cope with a suddenly large amount of objects to be weighed as described above. In the unlikely event that the gate opening / closing time is determined so as to cope with this, the production capacity will be significantly reduced.

  In addition, when the objects to be weighed are discharged from the hopper of the discharge combination including the weighing hopper to which a large amount of objects to be weighed as described above are supplied, the time required for the objects to be weighed to be stored in the bag of the packaging machine Becomes longer, and the object to be weighed bites into the lateral seal portion of the bag, which increases the probability of defective bag making.

  The configuration of Patent Document 2 does not assume a case where a very large amount of objects to be weighed are suddenly supplied to the weighing hopper as described above. It cannot respond to poor bag making.

  Moreover, in the structure of patent document 1, 2, the sensor for detecting the passage of a to-be-measured object is needed at the discharge port of a collection chute. Such a sensor also causes erroneous detection due to dirt or the like.

  The present invention has been made in order to solve the above-described problems. Even when a large amount of objects to be weighed is suddenly supplied to the hopper without causing a significant decrease in production capacity, A combination weigher that can reliably discharge all of the weighed material and prevent erroneous weighing, and can reduce the occurrence of defective bag making in such a packaging machine, and weighing using the same It aims to provide a packaging system.

  In order to achieve the above object, the combination weigher of the present invention holds a plurality of hoppers having a discharge gate for holding the supplied objects to be weighed and discharging the objects to be weighed. A combination process for obtaining one discharge combination composed of a combination of the hoppers in which the total weight of the objects to be weighed is within an allowable range with respect to a target weight; and a combination of the hoppers selected as the discharge combination at a predetermined first timing A plurality of control means for repeatedly performing a discharge process for discharging the object to be weighed from the hopper by closing the discharge gate after opening the discharge gate and maintaining the gate fully open state for a predetermined time. And a collecting chute for collecting the objects to be weighed discharged from the hopper and discharging them from a discharge port provided at a lower portion thereof, Includes a hopper whose weight ratio, which is the ratio of the weight of the object to be weighed held each time the combination processing is performed, to the target weight (hereinafter referred to as “overweight hopper”) is included in the discharge combination. And when the overload hopper is included, the time during which the overload hopper maintains the gate fully open state during the discharge process is set to be longer than the predetermined time. .

  According to this configuration, when the overload hopper is included in the discharge combination, the time for maintaining the gate fully open state of the overload hopper (gate fully open time) is longer than the predetermined time that is the gate fully open time of the hopper that is not the overload hopper. Thus, even when a large amount of objects to be weighed is suddenly supplied to the hopper, it is possible to reliably discharge all of the objects to be weighed in the hopper and prevent erroneous weighing. Further, only when the excessive amount hopper is included in the discharge combination, the gate full open time of the excessive amount hopper is lengthened, so that the production capacity is not significantly reduced. Further, it is not necessary to add a special mechanical part such as a sensor for detecting the passage of the object to be weighed at the discharge port of the collecting chute, and there is no problem such as erroneous detection of the sensor.

  In addition, the objects to be weighed discharged from the discharge port of the collective chute are supplied into the bag, a packaging machine for sealing the upper end of the bag in response to the discharge completion signal is disposed in the rear stage, and the control means Each time the discharge process is performed, a discharge notification process for outputting the discharge completion signal to the packaging machine is performed at a predetermined second timing. When the overload hopper is included in the discharge combination, the discharge notification process The timing for outputting the discharge completion signal may be configured to be later than the second timing.

  According to this configuration, when the excessive amount hopper is not included in the discharge combination, a discharge completion signal is output to the packaging machine at a predetermined second timing, and when the excessive amount hopper is included in the discharge combination, the discharge completion signal is output. By making the timing later than the second timing, it is possible to delay the timing at which the packaging machine seals the upper end of the bag to which the objects to be weighed are supplied, so that a large amount of objects to be weighed are suddenly supplied. Even if the time required for the object to be discharged from the hopper selected for the discharge combination including the overload hopper to be completely stored in the bag of the packaging machine becomes long, the object to be weighed is sealed at the upper end of the bag. Can be prevented, and the occurrence of defective bag making in the packaging machine can be reduced.

  Further, the control means calculates a gate full open time, which is a time during which the overload hopper maintains the gate fully open state, using the weight ratio of the overload hopper when the overload hopper is included in the discharge combination. Based on the gate full open time calculation formula, the gate full open time longer than the predetermined time is calculated, the gate of the excess hopper is opened and closed based on the calculated gate full open time, and the weight of the excess hopper The discharge notification time is calculated based on a discharge notification time calculation formula for calculating a discharge notification time that is a time from a predetermined time point to the output start time of the discharge completion signal using a ratio, and the calculated discharge The discharge completion signal may be output based on the notification time.

  According to this configuration, the gate full open time calculation formula is created based on the results of experiments or simulations, so that even if a large amount of objects are suddenly supplied to the hopper, It is possible to more reliably discharge all of the objects and prevent erroneous weighing. In addition, by preparing the discharge notification time calculation formula based on the results of experiments or simulations, the discharge notification time calculation formula can be applied from the hopper selected for the discharge combination including the overload hopper to which a large amount of objects to be weighed are suddenly supplied. Even if the weighing object is discharged, it is possible to further prevent the weighing object from biting into the sealed portion at the upper end of the bag, and to further reduce the occurrence of bag making defects in the packaging machine.

  In addition, when the control means is a weighing hopper for measuring the weight of an object to be weighed held by the overload hopper included in the discharge combination, a memory for storing the weight of the object to be weighed by the overweight hopper The overload hopper is included in the currently obtained discharge combination, and the overweight hopper is the weighing hopper, and the weight of the object to be weighed held in the overweight hopper is stored in the storage means in the past. When the stored weight exceeds the maximum value, the object to be weighed is discharged from the hopper selected for the currently obtained discharge combination, and then a new object to be weighed is supplied to the overweight hopper. It is determined whether or not an object to be weighed remains in the overload hopper based on the measured value of the overload hopper in a state where the overweight hopper is not. It may be configured so that the gate full open time correcting said gate full open time calculation formula to be longer issued.

  According to this configuration, the weight of the weighing object of the excess hopper included in the currently determined discharge combination (hereinafter referred to as the “current excess hopper”) is equal to the weight of the weighing object of the excess hopper included in the past discharge combination. When the weight exceeds the maximum value, it is determined whether or not all of the objects to be weighed have been discharged from the current overload hopper. By correcting the gate full-open time calculation formula so that the full-open time becomes longer, it becomes more certain that all the objects to be weighed can be discharged from the over-load hopper if it occurs afterwards, and erroneous weighing can be prevented. .

  In addition, the packaging machine is configured to output a biting detection signal to the control means when the weighted object is bitten in the sealed portion when the upper end of the bag is sealed. And the control means receives the bite detection signal from the packaging machine when the object to be weighed is discharged from the hopper selected as a discharge combination including the overload hopper, and the weight The discharge notification time calculation formula may be corrected so that the discharge notification time calculated with respect to the ratio becomes longer.

  According to this configuration, for example, when the object to be weighed is discharged from the hopper selected for the discharge combination including the overload hopper due to a change in the state of the object to be weighed due to a change in the ambient temperature, etc. If an object to be weighed in the sealed part at the upper end of the bag, correct the discharge notification time calculation formula so that the discharge notification time becomes longer, thereby preventing subsequent biting in the packaging machine. Occurrence of bag-making defects can be reduced.

  The weighing and packaging system of the present invention includes a combination weigher and a rear stage of the combination weigher, and an object to be weighed discharged from the combination weigher is supplied into the bag, and the bag is responsive to a discharge completion signal. The combination weigher, and the combination weigher holds a workpiece to be supplied and has a plurality of hoppers having discharge gates for discharging the workpiece to be weighed. A combination process for obtaining one discharge combination composed of a combination of the hoppers in which the total weight of the objects to be weighed is within an allowable range with respect to a target weight, and the discharge combination selected at a predetermined first timing Opening the discharge gate of the hopper and maintaining the fully open state of the gate, which is a fully open state, for a predetermined time, and then closing the discharge gate to discharge the object to be weighed from the hopper, and Control means for repeatedly performing a discharge notification process for outputting the discharge completion signal to the packaging machine at a predetermined second timing, and a cover disposed below the plurality of hoppers and discharged from the hoppers. A collecting chute for collecting the items to be collected and discharging them from the discharge port provided at the lower portion to the packaging machine, and the control means is configured to store the weight of the items to be weighed held each time the combination processing is performed. It is determined whether or not a hopper whose weight ratio, which is a ratio with respect to the target weight, exceeds a predetermined ratio (hereinafter referred to as “overweight hopper”) is included in the discharge combination. When the overload hopper maintains the gate fully open state when the operation is performed, the time is set longer than the predetermined time, and the discharge completion signal is output in the discharge notification process. The timing is set to be later than the second timing.

  According to this configuration, when the overload hopper is included in the discharge combination, the time for maintaining the gate fully open state of the overload hopper (gate fully open time) is longer than the predetermined time that is the gate fully open time of the hopper that is not the overload hopper. Thus, even when a large amount of objects to be weighed is suddenly supplied to the hopper, it is possible to reliably discharge all of the objects to be weighed in the hopper and prevent erroneous weighing. Further, only when the excessive amount hopper is included in the discharge combination, the gate full open time of the excessive amount hopper is lengthened, so that the production capacity is not significantly reduced. In addition, when the discharge combination does not include an excessive amount hopper, a discharge completion signal is output to the packaging machine at a predetermined second timing, and when the discharge combination includes an excessive amount hopper, the discharge completion signal is output at a second timing. Since the timing when the packaging machine seals the upper end of the bag to which the objects to be weighed are sealed can be delayed by delaying from the timing of the above, an overload hopper that suddenly supplies a large amount of objects to be weighed is included. Even if the time required for the object to be discharged from the hopper selected for the discharge combination to be completely stored in the bag of the packaging machine becomes longer, the object to be weighed bites into the sealing part at the upper end of the bag. Can be prevented, and the occurrence of bag-making defects in the packaging machine can be reduced.

  The present invention has the above-described configuration, and even when a large amount of objects to be weighed is suddenly supplied to the hopper without causing a significant decrease in production capacity, Provided is a combination weigher capable of reliably discharging and preventing erroneous weighing, and further capable of reducing the occurrence of defective bag making in a packaging machine, and a weighing and packaging system using the same. There is an effect that can be.

It is a schematic diagram which shows schematic structure of the measurement packaging system comprised with the combination weigher and packaging machine in embodiment of this invention. It is a block diagram which shows the outline of the control system of the combination weigher in embodiment of this invention. It is a timing chart which shows an example of the opening / closing operation | movement of the gate of the hopper selected as the discharge | emission combination of the combination scale in embodiment of this invention, and operation | movement of the horizontal sealing machine of a packaging machine. (A) is the figure which graphed the gate full open time calculation formula, (b) is the figure which graphed the discharge notification time calculation formula. It is a flowchart which shows an example of operation | movement of the combination scale in embodiment of this invention. It is a flowchart which shows an example of operation | movement of the combination scale in 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.

(Embodiment)
FIG. 1 is a schematic diagram illustrating a schematic configuration of a weighing and packaging system including a combination weigher and a packaging machine according to an embodiment of the present invention.

  The weighing and packaging system includes a combination weigher 1 and a packaging machine 2 that is disposed at a subsequent stage of the combination weigher 1 and in which an object to be weighed discharged from the combination weigher 1 is dropped into a bag for bag making.

  The combination weigher 1 of the present embodiment is provided with a conical dispersion feeder 11 that disperses the object to be weighed supplied from an external supply device (not shown) radially by vibration at the center of the upper part of the device. A weight level sensor 18 such as a load cell is attached to the dispersion feeder 11, and the measurement value of the weight level sensor 18 is output to the combination weigher control unit 31. The combination weigher control unit 31 is based on the measurement value of the weight level sensor 18. A supply device (not shown) is controlled so that the objects to be weighed on the dispersion feeder 11 are kept constant. Around the dispersion feeder 11, linear feeders 12 are provided for feeding the objects to be weighed sent from the dispersion feeder 11 to the respective supply hoppers 13 by vibration. Below the linear feeder 12, a plurality of supply hoppers 13, weighing hoppers 14, and memory hoppers 15 are provided correspondingly and arranged in a circular shape. The supply hopper 13 has a discharge gate 13g for temporarily holding an object to be weighed sent from the linear feeder 12 and discharging the object to be weighed to a weighing hopper 14 arranged below the object.

  The weighing hopper 14 temporarily holds an object to be weighed supplied from the upper supply hopper 13 and discharges the object to the upper collecting chute 16 and a memory hopper disposed obliquely below. 15 and a discharge gate 15b for discharging to the top 15 and configured to selectively discharge the objects to be measured to the upper collecting chute 16 and the memory hopper 15. A weight sensor 19 such as a load cell is attached to the weighing hopper 14, and the weight sensor 19 measures the weight of an object to be weighed in the weighing hopper 14. The measurement value of each weight sensor 19 is output to the combination scale control unit 31.

  The memory hopper 15 has a discharge gate 15 g for temporarily holding an object to be weighed supplied from the weighing hopper 14 obliquely above, and for discharging the object to be measured to the upper collecting chute 16.

  The upper collecting chute 16 is provided below the weighing hopper 14 and the memory hopper 15, and a funnel-shaped lower collecting chute 17 is disposed below the upper collecting chute 16. The objects to be weighed discharged from the weighing hopper 14 and the memory hopper 15 slide down on the upper collecting chute 16 and are collected by the lower collecting chute 17 and discharged from the discharge port 17a to the packaging machine 2. The lower collecting chute 17 and the upper collecting chute 16 constitute a collecting chute.

  FIG. 2 is a block diagram showing an outline of a control system of the combination weigher 1 in this embodiment.

  The combination weigher control unit (control means) 31 includes a CPU, a ROM and RAM memory storing operation programs, operation parameters, and the like of the CPU, a microcomputer including an I / O unit, a timer, and the like. An arithmetic control unit 311 configured by the CPU, an I / O unit and a timer, and a storage unit 312 configured by the memory are included. Then, the CPU of the arithmetic control unit 311 executes the operation program stored in the ROM of the storage unit 312 to control the overall operation of the combination weigher 1 and perform combination processing. The combination weigher controller 31 outputs a discharge completion signal x (FIG. 1) to the packaging machine controller 21 when discharging the objects to be weighed from the combination weigher 1 to the packaging machine 2.

  An operation setting indicator 3 not shown in FIG. 1 includes, for example, a touch screen type display screen, and inputs means for operating the combination weigher 1 and setting its operation, an operation speed, a measured value, and the like. Display means for displaying on the screen.

  The combination weigher control unit 31 exchanges signals with the packaging machine control unit 21 and also exchanges signals with the operation setting display 3. Further, the combination weigher control unit 31 controls a supply device (not shown) based on the measurement value of the weight level sensor 18 input via the A / D conversion circuit 33. Further, the vibration amplitude of the dispersion feeder 11 and its operation time are controlled via the vibration control circuit 32. Further, the vibration amplitude of the linear feeder 12 and its operation time are controlled via the vibration control circuit 34. The actuator for opening and closing the discharge gate 13g of the supply hopper 13 and the discharge gates 14a and 14b of the weighing hopper 14 is controlled via the gate drive circuit 35. The measurement value of the weight sensor 19 attached to the weighing hopper 14 is received via the A / D conversion circuit 36. Further, an actuator for opening and closing the discharge gate 15 g of the memory hopper 15 is controlled via the gate drive circuit 37.

  The linear feeder 12 and its vibration control circuit 34, the supply hopper 13, the weighing hopper 14 and their gate drive circuit 35, the weight sensor 19 and the A / D conversion circuit 36, the memory hopper 15 and its gate drive circuit 37. A plurality of weighing units 41 are provided.

  In the combination processing by the combination weigher control unit 31, one hopper combination in which the total weight value of the objects to be weighed is within an allowable range with respect to the target weight is obtained from the plurality of weighing hoppers 14 and the memory hopper 15, The combination is the discharge combination. When there are a plurality of hopper combinations that fall within the allowable range described above, one hopper combination having the smallest absolute value of the difference between the total weight value of the objects to be weighed and the target weight is obtained and determined as the discharge combination. Here, the measured value by the weight sensor 19 is used for the weight value of the weighing object in the weighing hopper 14, and the weight sensor 19 in the weighing hopper 14 thereabove is used as the weight value of the weighing object in the memory hopper 15. Is stored in the storage unit 312 and is used.

  The objects to be weighed in the hopper (hereinafter also referred to as “discharge hopper”) selected as the discharge combination obtained by the above combination processing are discharged onto the upper collecting chute 16.

  Note that the combination weigher control unit 31 is not necessarily configured by a single control device, and a plurality of control devices are distributed and configured to control the operation of the combination weigher 1 in cooperation with each other. It may be.

  Moreover, the packaging machine 2 is a vertical pillow packaging machine, and as shown in FIG. 1, from a tube 51 serving as a receiving port for an object to be weighed discharged from the combination weigher 1 and a roll of packaging material (not shown). A former 52 for winding the drawn sheet-like packaging material 50 around the tube 51 to form a cylinder, a pull-down belt machine 53 that sucks and sends the packaging material 50 downward, and a cylindrical packaging material A vertical sealing machine 54 that seals 50 stacked vertical edges (sealing by welding), and a horizontal seal (below the upper end of the preceding bag and the lower end of the subsequent bag disposed below the tube 51 ( And a horizontal sealing machine (a pair of sealing jaws) 55 that performs sealing by welding. The horizontal sealing machine 55 has a built-in cutter for separating the preceding bag and the succeeding bag.

  Further, the packaging machine 2 is provided with biting detection means (not shown). This biting detection means is configured by using, for example, a proximity sensor or the like, and when sealing is performed by the horizontal sealing machine 55, the horizontal sealing machine 55 pinches the bag from both sides, but the gap between the two is larger than a predetermined value. The bite is detected. In addition, what is necessary is just to use a well-known thing as a biting detection means.

  Moreover, the packaging machine 2 is provided with the packaging machine control part 21 which controls the operation | movement of the whole. The packaging machine control unit 21 includes a CPU, a ROM and RAM memory in which an operation program and operation parameters of the CPU are stored, an I / O unit, a microcomputer including a timer, and the like. The CPU controls the overall operation of the packaging machine by executing the operation program stored in the ROM. The packaging machine control unit 21 outputs a discharge request signal y requesting the combination weigher 1 to discharge the objects to be weighed to the combination scale control unit 31 and detects the biting by the biting detection unit. The biting detection signal z is output to the combination scale control unit 31. The combination scale control unit 31 can recognize the occurrence of biting in the packaging machine 2 by receiving the biting detection signal z from the packaging machine 2.

  First, an outline of the operation of the weighing and packaging system including the combination weigher 1 and the packaging machine 2 in the present embodiment configured as described above will be described. The operation of the combination weigher 1 is controlled by a combination weigher control unit 31 (hereinafter also simply referred to as “control unit 31”), and the operation of the packaging machine 2 is controlled by the packaging machine control unit 21.

  First, an object to be weighed is conveyed above the combination scale 1 by a supply device (not shown) and placed on the dispersion feeder 11. Then, the objects to be weighed are supplied to the supply hopper 13 through the linear feeders 12 following the dispersion feeder 11 after being dispersed radially by the vibration of the dispersion feeder 11. When the weighing hoppers 14 located below the supply hoppers 13 are empty, the objects to be weighed in the supply hoppers 13 are supplied to the weighing hoppers 14. Further, when the memory hopper 15 located below each weighing hopper 14 is empty, the objects to be weighed in each weighing hopper 14 are supplied to the memory hopper 15.

  And the control part 31 calculates | requires discharge | emission combination from the weighing hopper 14 and the memory hopper 15 by the above-mentioned combination process, and when the discharge request signal y from the packaging machine 2 is input, from the discharge hopper selected as the discharge combination. The objects to be weighed are discharged onto the upper collecting chute 16 and a discharge completion signal x is output to the packaging machine 2. The objects to be weighed discharged from the discharge hopper slide down on the upper collecting chute 16 and are discharged from the outlet 17a of the lower collecting chute 17 to the packaging machine 2.

  The packaging machine 2 fills and packs the objects to be weighed discharged from the combination scale 1 while manufacturing the bags. In this packaging machine 2, a sheet-like packaging material 50 drawn from a roll of packaging material is wound around a tube 51 by a former 52 and formed into a cylindrical shape, and is adsorbed by a pull-down belt machine 53 and sent downward. The stacked vertical edges of the cylindrical packaging material 50 are sealed by the vertical sealing machine 54. Then, the objects to be weighed discharged from the combination weigher 1 are filled into the cylindrical packaging material 50 through the tube 51, and horizontally spread across the upper end of the preceding bag and the lower end of the subsequent bag by the horizontal sealing machine 55. Directional sealing is performed. This horizontal sealing is started in response to the discharge completion signal x from the combination scale 1. By performing the horizontal sealing, the preceding bag becomes a complete bag whose upper and lower sides are sealed because the lower end is sealed by the previous horizontal sealing. Then, the center of the horizontal seal portion is cut by a cutter built in the horizontal sealing machine 55, and the preceding bag and the subsequent bag are separated. Thereafter, the above operation is repeated.

  Hereinafter, the operation of the weighing packaging system of the present embodiment will be described in more detail. FIG. 3 is a timing chart showing an example of the opening / closing operation of the discharge hopper of the combination weigher and the operation of the horizontal sealing machine of the packaging machine in the weighing packaging system of the present embodiment.

  In FIG. 3, when the discharge request signal y is input from the packaging machine control unit 21, the control unit 31 simultaneously opens the gates of the discharge hoppers selected for the discharge combination in response to the discharge request signal y. The object to be weighed is discharged (time t1).

  Then, a discharge completion signal x is output to the packaging machine control unit 21 after the time T2 has elapsed since the gate of the discharge hopper started to open.

  When the packaging machine control unit 21 receives the discharge completion signal x from the combination weigher control unit 31, the packaging machine control unit 21 starts the operation of the horizontal sealing machine 55 and performs horizontal sealing. That is, the object to be weighed discharged from the discharge hopper that has started to open the gate at time t1 is put into the packaging bag by time t2, and the horizontal seal that seals the upper end portion of the packaging bag at time t2 is lateral. It is started by the sealing machine 55.

  And the above operation | movement is performed repeatedly. Here, the packaging machine control unit 21 starts the operation of the horizontal sealing machine 55 as soon as the discharge completion signal x is input. However, the horizontal sealing is performed after a predetermined time elapses after the discharge completion signal x is input. The operation of the machine 55 may be started. In addition, the combination weigher control unit 31 starts to open the gate of the discharge hopper as soon as the discharge request signal y is input, but starts to open the gate after a predetermined time has elapsed since the input of the discharge request signal y. May be.

  In the present embodiment, for the weighing hopper 14 and the memory hopper 15 selected as the discharge combination, the opening operation time To from when the gate starts to the fully opened state until the fully opened state and the time for maintaining the fully opened state are maintained. (Gate fully open time) The initial set value T1s of T1 and the closing operation time Tc from the fully open state to the fully closed state starting from the fully closed state are set in advance. Also, an initial set value T2s of a time (discharge notification time) T2 from when the discharge hopper starts to open its gate to when the discharge completion signal x starts to be output is also set in advance. In the present embodiment, the times To, T1s, and Tc in the gate opening / closing operation are set to be the same in the weighing hopper 14 and the memory hopper 15. In addition, in the state where the gate full open time T1 of the weighing hopper 14 and the memory hopper 15 is set to be the same, the amount that can be discharged in the gate opening / closing operation is the same for the weighing hopper 14 and the memory hopper 15. It shall be.

  Then, the control unit 31 calculates a weight ratio r (= Wx / Wt) which is a ratio of the weight value Wx of the objects to be weighed held in each discharge hopper to the target weight value Wt, and sets the weight ratio r to the weight ratio r. Accordingly, the gate fully open time T1 and the discharge notification time T2 are obtained as follows.

For all discharge hoppers selected for the discharge combination,
r ≦ r _t
If so, the gate fully open time T1 and the discharge notification time T2 are the initial set values T1s and T2s, respectively. Incidentally, _{r t} is a predetermined value (e.g., 0.5). If r _t is 0.5, not more than 50% of the weight value Wx is the target weight value Wt of the objects to be weighed which are held in each of all the discharge hoppers, the gate full open time T1 and the discharge notification time T2 Are initial set values T1s and T2s, respectively.

Of the hoppers selected for the discharge combination, the weight ratio r is r> r _t
If there is a hopper (hereinafter referred to as “overload hopper”), the gate full open time T1 of the excess hopper is set to a value greater than the initial set value T1s, and the discharge notification time T2 is set to a value greater than the initial set value T2s. .

The gate full open time T1 of this overload hopper is calculated based on, for example, the gate full open time calculation formula shown by the following formula (1).
T1 = T1s + f (r) (1)
In this equation (1), when f (r) = a (r−r _t ), the gate full open time calculation equation is the following equation (2). Note that a is a predetermined value.
T1 = T1s + a (r−r _t ) (2)
Here, for example, when the weighing cycle is 1 second and To = Tc = 200 (ms), if T1s = 10 (ms), r _t = 0.5, and a = 80, the weight ratio of the excess hopper When r is 0.8, the overload hopper gate full open time T1 = 34 (ms).

In addition, in the equation (1), when f (r) = b√ (r−r _t ), the gate full open time calculation equation is the following equation (3). Note that b is a predetermined value.
T1 = T1s + b√ (r−r _t ) (3)
Here, for example, when the weighing cycle is 1 second and To = Tc = 200 (ms), if T1s = 10 (ms), r _t = 0.5, and b = 50, the weight ratio of the excess hopper When r is 0.8, the gate full open time T1 of the overdose hopper is about 37 (ms).

  FIG. 4A is a graph of the gate full open time calculation formula, where the straight line L1 represents the gate full open time calculation formula shown by the formula (2), and the curve L2 is the gate full open formula shown by the formula (3). Represents the time calculation formula.

  The initial set value T1s for the gate fully open time is a value set according to the target weight value Wt. The target supply amount (the hopper target supply amount) of the objects to be weighed supplied to each weighing hopper 14 is obtained by dividing the target weight value Wt by the combination selection planned number (the planned number of hoppers selected for one discharge combination). The vibration amplitude and operation time of the linear feeder 12 are set according to the hopper target supply amount. In addition, an opening / closing operation pattern including a gate full open time (initial setting value T1s) of a gate that opens and closes in order to discharge objects to be weighed in the hoppers of the supply hopper 13, the weighing hopper 14, and the memory hopper 15 is also a hopper target supply amount ( A value obtained by dividing the target weight value Wt by the planned combination selection number). Therefore, the initial set value T1s of the gate fully open time is a value set according to the target weight value Wt.

  Therefore, in this embodiment, based on the weight ratio r of the weight value Wx of the discharge hopper to be weighed with respect to the target weight value Wt, the presence / absence of the overload hopper is determined. T1 is made longer according to the weight ratio r of the excess hopper.

For example, when the opening operation time To and the closing operation time Tc are constant, the weight value of the object to be weighed in the weighing hopper is changed several times, and the same value as the weight value of the object to be weighed in the weighing hopper is measured each time. The minimum gate full open time during which all objects to be weighed in the hopper can be discharged is obtained through experiments or simulations in advance. From the results, the weight ratio (weight value of the object to be weighed in the weighing hopper ÷ target weight value Wt) and the minimum gate fully open time are obtained from each result. Based on this, a gate full open time calculation formula such as formula (2) or formula (3) is derived and stored in the storage unit 312 in advance. Note that when the weight ratio and the minimum gate full open time at each time are obtained, the target weight value Wt and the initial set value T1s of the gate full open time are known values, and when the equation (2) is derived, a predetermined value is used. a, it may be determined to _{r t,} when deriving the equation (3) may be determined a predetermined value b, _{r t.} In either case, it is approximated. Using the weight ratio and the minimum gate full opening time obtained above, an approximate expression showing the relationship between the weight ratio and the minimum gate full open time is obtained by a well-known method such as the least square method. The equation may be a gate full open time calculation equation.

  Further, instead of using the gate full open time calculation formula, for example, a relationship indicated by a chain line L3 is created based on the result of the above-described experiment or simulation, and the relationship is stored in the storage unit 312 as a table, for example. In some cases, the gate full open time T1 may be obtained by referring to the table.

In addition, the discharge notification time T2 when there is an excessive amount of hopper is calculated based on, for example, a discharge notification time calculation formula expressed by the following equation (4).
T2 = T2s + g (r) (4)
In this formula (4), the discharge notification time calculation formula when g (r) = c (r−r _t ) is the following formula (5). Note that c is a predetermined value.
_{T2 = T2s + c (r-} r t) ··· (5)
In this case, for example, if T2s = 500 (ms), r _t = 0.5, and c = 200, the discharge notification time T2 = 560 (ms) is obtained when the weight ratio r of the excess hopper is 0.8. .

In addition, in the equation (4), the discharge notification time calculation equation when g (r) = d√ (r−r _t ) is the following equation (6). D is a predetermined value.
T2 = T2s + d√ (r−r _t ) (6)
In this case, for example, if T2s = 500 (ms), r _t = 0.5, and d = 140, the discharge notification time T2 is about 577 (ms) when the overweight hopper weight ratio r is 0.8. Become.

  FIG. 4B is a graph of the discharge notification time calculation formula, in which the straight line L4 represents the discharge notification time calculation formula shown by the formula (5), and the discharge notification shown by the curve L5 by the formula (6). Represents the time calculation formula.

  It should be noted that the objects to be weighed discharged from all the hoppers selected as the discharge combination are slipped down the collecting chutes 16 and 17 completely in the bag of the packaging machine 2 as the amount thereof is large (the weight value is large). Since the time until the storage becomes longer, the initial set value T2s of the discharge notification time is a value set according to the target weight value Wt. On the other hand, the larger the amount of objects to be weighed from one hopper (the larger the weight value), the longer the time for discharging all objects to be weighed from the hopper, and The time until it slides down and is completely stored in the bag of the packaging machine 2 becomes longer.

  Therefore, in the present embodiment, the presence / absence of the excessive amount hopper is determined based on the weight ratio r of the weight value Wx of the hopper to be weighed with respect to the target weight value Wt, and the discharge notification time T2 when the excessive amount hopper is included in the discharge combination. Is increased in accordance with the weight ratio r of the excess hopper.

For example, the total weight of the objects to be weighed in a plurality of weighing hoppers is set to a weight within an allowable range with respect to the target weight value Wt that can be selected for the discharge combination, and the weight value of the objects to be weighed in a certain weighing hopper (overweight) (Value) is increased, and the discharge gates of the plurality of weighing hoppers are opened to discharge the objects to be weighed (in this case, the discharge gates need not be closed). The time (discharge notification time) required from when the discharge gate at this time is started to when all of the objects to be weighed are stored in the bag of the packaging machine 2 is obtained through experiments or simulations in advance. Then, the excessive weight value is changed several times, and the discharge notification time at each time is similarly obtained by performing an experiment or simulation. From these results, the weight ratio (overweight value / target weight value Wt) and the discharge notification time at each time are obtained. Based on this, a discharge notification time calculation formula such as formula (5) or formula (6) is derived, and stored in the storage unit 312 in advance. The initial setting value of the target weight value Wt discharge notification time T2s is a known value, the predetermined ratio r _t have asked when determining the previously gate full open time calculation formula. When the equation (5) is derived, the predetermined value c may be obtained, and when the equation (6) is derived, the predetermined value d may be obtained. In either case, it is approximated. In addition, using the weight ratio and the discharge notification time obtained above, an approximate expression indicating the relationship between the weight ratio and the discharge notification time is obtained by a known method such as the least square method, and the approximate expression is calculated as the discharge notification. It is good also as a time calculation formula. Further, in the case of obtaining the discharge time of notification calculation formula in either method, to calculate the predetermined ratio r _t as an unknown value, it is configured to use the calculated value as the predetermined ratio r _t of the discharge notification time calculation formula You can also. In this case, there is a predetermined ratio r _t in the gate full open time calculation formula and a discharge notification time calculation formula is different. In the following description, a predetermined ratio r _t in the gate full open time calculation formula and a discharge notification time calculation formula will be described when the same.

  Further, instead of using the discharge notification time calculation formula, for example, a relationship indicated by a chain line L6 is created based on the result of the above-described experiment or simulation, and the relationship is stored in the storage unit 312 as a table, for example. When an excessive amount hopper is included, the discharge notification time T2 may be obtained with reference to the table.

  5 and 6 are flowcharts showing an example of the operation of the combination weigher according to the embodiment of the present invention. This operation is performed by the control unit 31. Information necessary for performing the following operations (for example, target weight Wt, weight ratio r, gate fully open time initial setting value T1s, discharge notification time initial setting value T2s, gate full open time calculation formula, and discharge notification time) All the calculation formulas and the like are stored in the storage unit 312, and all information such as measurement values to be stored during the operation is also stored in the storage unit 312.

  Further, in this operation example, a supply stop flag and an overdose flag are provided corresponding to each weighing hopper 14, an overdose hopper discharge flag is provided for the entire combination weigher, and each flag area is stored in the storage unit 312. Is provided. Hereinafter, setting a flag (setting a value to 1) is referred to as turning on the flag, and dropping a flag (setting a value to 0) is referred to as turning off the flag. These flags are all turned off at the start of the first operation after the combination weigher is turned on. Here, when the weighing hopper 14 is an overload hopper, the weighing object is not supplied from the weighing hopper 14 to the memory hopper 15, but this is not restrictive. Also, here, a weight sorter (not shown) is installed at the subsequent stage of the packaging machine 2, and in this weight sorter, whether the weight of the object to be weighed packed by the packaging machine 2 is within a predetermined weight range. The product is inspected to determine whether it is not within the predetermined weight range, and is rejected as a defective product.

  First, in step S1 of FIG. 5, it is determined whether or not there is a weighing hopper whose supply stop flag is ON. If there is, the process proceeds to step S11, and if not, the process proceeds to step S2.

  In step S2, supply processing is performed. In this supply process, the discharge gate 14b of the weighing hopper 14 above the empty memory hopper 15 is opened and closed to supply the object to be weighed from the weighing hopper 14, and the empty weighing hopper 14 is supplied to the empty measurement hopper 14. The discharge gate 13g of the upper supply hopper 13 is opened and closed to supply the object to be weighed from the supply hopper 13. However, the object to be weighed is not supplied from the weighing hopper 14 in which the excessive amount flag is ON to the memory hopper 15.

Next, in step S3, the weighing value of each weighing hopper 14 (the weight value of the object to be weighed held by each weighing hopper 14 measured by each weight sensor 19) is acquired, and whether or not it is an overload hopper is determined. The overload flag corresponding to the weighing hopper 14 that has been determined and determined to be an overdose hopper is turned ON (weighing process). The determination as to whether or not it is an overdose hopper is made by calculating the aforementioned weight ratio r for each weighing hopper 14, comparing the weight ratio r with a predetermined ratio r _t, and when exceeding the predetermined ratio r _t , the weighing hopper 14 Is determined as an overdose hopper.

  In the next step S4, the combination process described above is performed to obtain a discharge combination.

  In the next step S5, it is determined whether or not there is an overdose hopper in the discharge combination by determining whether or not there is an overdose flag corresponding to the selected hopper in the discharge combination obtained in step S4. If not included, the process proceeds to step S21. If not included, the process proceeds to step S6.

  And if the discharge request signal y is input from the packaging machine in step S6, it will progress to step S7 and will perform discharge processing. In this discharge process, the objects to be weighed are discharged onto the upper collecting chute 16 from the hopper selected as the discharge combination. In this step S7, the gate fully open time of the hopper for discharging the object to be weighed is an initial set value (T1s).

  In the next step S8, it is determined whether or not the excessive hopper discharge flag is ON. If it is not ON, the process proceeds to step S10. If it is ON, the excessive hopper discharge flag is turned OFF in step S9 and the process proceeds to step S10. move on. In step S10, the discharge completion signal x is output to the packaging machine control unit 21 at a timing based on the initial set value T2s of the discharge notification time, and the process returns to step S1.

  If it is determined in step S5 that the excessive amount hopper is included in the discharge combination, the process proceeds to step S21. In step S21, the measurement value of the excessive amount hopper (weighing hopper 14) included in the discharge combination is stored in the storage unit 312. Is stored in an overdose hopper weighing value storage area. Next, in step S22, it is determined whether or not the measurement value stored this time in step S21 has exceeded the maximum measurement value (the past maximum measurement value) stored in the excess hopper measurement value storage area. If it does not exceed, the process proceeds to step S24, and if it exceeds, the supply stop flag corresponding to the weighing hopper 14 that is the current overload hopper is turned on (step S23), and the process proceeds to step S24.

  Next, in step S24, the gate full open time of the excess hopper is calculated based on the above-described gate full open time calculation formula, and in step S25, the discharge notification time is calculated based on the above discharge notification time calculation formula.

  And if the discharge request signal y is input from a packaging machine by step S26, it will progress to step S27 and will perform discharge processing. In this discharge process, as in step S7, the objects to be weighed are discharged from the hopper selected as the discharge combination onto the upper collecting chute 16, but the gate fully open time of the overload hopper is set to the time calculated in step S24. The gate fully open time of the hoppers other than the excessive amount hopper is the initial set value (T1s) as in step S7. Then, the excessive amount flag corresponding to the excessive amount hopper that has discharged the object to be weighed is turned OFF.

  Next, in step S28, the overdose hopper discharge flag is turned ON. In step S29, the discharge completion signal x is output to the packaging machine control unit 21 at the timing based on the discharge notification time T2 calculated in step S25, and the process returns to step S1.

  If there is a weighing hopper 14 in which the supply stop flag is ON in step S1, the process proceeds to step S11, and the hoppers other than the weighing hopper 14 in which the supply stop flag is ON are the same as in step S2. The supply process is performed. That is, in step S11, when the weighing object to be weighed is held in the weighing hopper 14 above the empty memory hopper 15, and the overload flag of the weighing hopper 14 is OFF, the weighing hopper 14 stores the memory. The object to be weighed is supplied to the hopper 15 and the object to be weighed is supplied from the supply hopper 13 above the weighing hopper 14 whose supply stop flag is OFF and empty.

  Next, in step S12, as in step S3, the weighing value of each weighing hopper 14 is acquired, it is determined whether or not it is an overdose hopper, and an overdose flag corresponding to the overdose hopper is turned on (weighing process). In step S13, it is determined whether there is no object to be weighed in the weighing hopper 14 for which the supply stop flag is ON (that is, whether the weighing value of the weighing hopper 14 is zero). If not, the supply stop flag of the weighing hopper 14 is turned off in step S14, and the process proceeds to step S4. If it is determined that the object to be weighed remains, the gate full open time calculation formula is corrected in step S15 and the process proceeds to step S4.

  In step S15, the calculation formula is corrected so that the gate full-open time at an arbitrary weight ratio r obtained by the gate full-open time calculation formula becomes longer. Specifically, for example, when the gate full open time calculation formula is the formula (2), the value of the predetermined value a is increased. For example, the value of the predetermined value a is increased by 1.2 times. Further, when the gate full open time calculation formula is the formula (3), the value of the predetermined value b is increased. For example, the value of the predetermined value b is multiplied by 1.2.

  Moreover, the control part 31 will perform the following processes, if the biting detection signal z is input from the packaging machine control part 21. FIG. That is, when the biting detection signal z is input in step S41 of FIG. 6, it is determined whether or not the excessive hopper discharge flag is ON. If not, the process proceeds to step S45, and if it is ON, step S43 is determined. , The discharge notification time calculation formula is corrected, the excessive hopper discharge flag is turned OFF, and the process proceeds to step S45.

  In step S43, the calculation formula is corrected so that the discharge notification time at an arbitrary weight ratio r obtained by the discharge notification time calculation formula becomes longer. Specifically, for example, when the discharge notification time calculation formula is the formula (5), the value of the predetermined value c is increased. For example, the value of the predetermined value c is increased to 1.2 times. Further, when the discharge notification time calculation formula is the formula (6), the value of the predetermined value d is increased. For example, the predetermined value d is increased to 1.2 times.

  Next, in step S45, for example, an alarm notifying that the biting has been detected by the packaging machine is output from the operation setting display 3, and the operation of the combination weigher is stopped (step S46). In this case, since the biting has occurred in the packaging machine and the operation is stopped, the operator restarts the operation of the packaging machine and the combination weigher after performing a predetermined recovery procedure.

  When the operation is stopped by performing steps S43 and S44, when the combination weigher control unit 31 performs step S25 after restarting the operation, the discharge notification is calculated based on the discharge notification time calculation formula corrected in step S43. Calculate time.

  In this embodiment, when an excessive amount hopper is included in the discharge combination, the gate fully open time T1 of the excessive amount hopper is set to a time longer than the gate full open time T1s of the hopper that is not the excessive amount hopper, thereby suddenly measuring a large amount. Even when an article is supplied to the hopper, all the objects to be weighed by the hopper can be reliably discharged to prevent erroneous weighing. Further, only when the excessive amount hopper is included in the discharge combination, the gate full open time T1 of the excessive amount hopper is lengthened, so that the production capacity is not significantly reduced. Here, the gate full open time calculation formula for calculating the gate full open time T1 of the overload hopper is created based on the results of experiments or simulations, so that the discharge of all the objects to be weighed by the overload hopper is more reliably performed. It is possible to further prevent erroneous measurement.

  In addition, when an excessive amount of hopper is included in the discharge combination, the timing for outputting the discharge completion signal x to the packaging machine 2 can be delayed to delay the timing for the horizontal sealing machine 55 of the packaging machine 2 to seal. Even if it takes a long time to completely store the objects to be discharged from the hopper selected in the discharge combination including the overload hopper to which a large amount of objects are supplied in the bag of the packaging machine 2 Further, it is possible to prevent the object to be weighed from biting into the lateral seal portion (sealing portion) of the bag, and to reduce the occurrence of bag making defects in the packaging machine 2. Here, when an overdose hopper is included in the discharge combination, a discharge notification time calculation formula for calculating a discharge notification time T2 for determining the timing of outputting the discharge completion signal x to the packaging machine 2 is obtained as a result of an experiment or a simulation. By making it based on this, it is possible to further reduce the occurrence of bag-making defects due to biting of objects to be weighed at the seal portion of the bag of the packaging machine 2.

  In this embodiment, when the overload hopper is included in the discharge combination, the gate full open time T1 of only the overload hopper is lengthened. However, the gate full open time T1 of other hoppers included in the discharge combination is also long. May be. However, for example, when the packaging speed set in the packaging machine 2 is faster than the discharge speed of the objects to be weighed set in the combination weigher 1, the gate full open time T1 of only the overload hopper is lengthened and the combination processing is made constant. By performing the cycle, it may be possible to maintain a constant speed without delaying the discharge speed of the combination weigher 1.

  In the present embodiment, the weight of the weighing object of the overload hopper included in the currently determined discharge combination (hereinafter referred to as “current overload hopper”) is the weight of the overload hopper included in the past discharge combination. If the weight exceeds the maximum weight, it is determined whether or not all the objects to be weighed have been discharged from the current overweight hopper. By correcting the gate full open time calculation formula so that the gate full open time becomes longer (step S15), it becomes more certain that all of the objects to be weighed can be discharged from the excess quantity hopper when the excess quantity hopper is generated thereafter. Incorrect weighing can be prevented.

  In this embodiment, for example, when the object to be weighed is discharged from the hopper selected as the discharge combination including the excessive hopper due to a change in the state of the object to be weighed due to a change in the ambient temperature or the like, the packaging machine If the object to be weighed in the seal portion of the bag in 2, the discharge notification time calculation formula is corrected so that the discharge notification time T <b> 2 becomes longer (step S <b> 43), and the subsequent biting in the packaging machine 2 is performed. It is possible to reduce the occurrence of defective bag making.

  Further, in this embodiment, it is not necessary to add a special mechanical component such as a sensor for detecting the passage of the object to be weighed to the discharge port 17a of the collective chute, and there is a problem such as erroneous detection of the sensor. Absent.

  In addition, the structure of the combination balance 1 in this embodiment is an example, and can be variously changed. For example, the memory hopper 15 may not be provided. In the case where the memory hopper 15 is not provided, the weighing hopper 14 does not need to discharge the objects to be measured in two directions, and only needs to be able to discharge the objects to be measured onto the collecting chute 16. In this case, the discharge combination is determined by the combination of only the weighing hopper 14.

  Even if a large amount of objects to be weighed are suddenly supplied to the hopper without causing a significant decrease in production capacity, the present invention reliably discharges all of the objects to be weighed in the hopper, resulting in erroneous weighing. It is useful as a combination weigher and a measuring and packaging system using the same.

DESCRIPTION OF SYMBOLS 1 Combination scale 2 Packaging machine 3 Operation setting display 11 Dispersion feeder 12 Linear feeder 13 Supply hopper 14 Weighing hopper 15 Memory hopper 16 Upper assembly chute 17 Lower assembly chute 17a Discharge port 18 Weight level sensor 19 Weight sensor 21 Packaging machine control part 31 Combination Weighing Control Unit 50 Packaging Material 51 Tube 52 Former 53 Pull-down Belt Machine 54 Vertical Sealing Machine 55 Horizontal Sealing Machine

Claims (6)

A plurality of hoppers having a discharge gate for holding the supplied objects to be weighed and discharging the objects to be weighed;
A combination process for obtaining one discharge combination composed of a combination of the hoppers in which the total weight of the objects to be weighed is within an allowable range with respect to the target weight, and the discharge combination is selected at a predetermined first timing. Control means for repeatedly performing a discharge process for discharging the object to be weighed from the hopper by opening the discharge gate of the hopper, maintaining the gate fully open state for a predetermined time, and then closing the discharge gate. When,
A collecting chute arranged below the plurality of hoppers, for collecting the objects to be weighed discharged from the hoppers, and discharging them from a discharge port provided at a lower part,
The control means is configured so that each time the combination process is performed, a hopper whose weight ratio, which is a ratio of the weight of the objects to be weighed with respect to the target weight, exceeds a predetermined ratio (hereinafter referred to as “overweight hopper”) is discharged. It is determined whether or not it is included in a combination, and when the overload hopper is included, the time during which the overload hopper maintains the gate fully open state when performing the discharging process is configured to be longer than the predetermined time. A combination weigher. An object to be weighed discharged from the discharge port of the collecting chute is supplied into the bag, and a packaging machine that seals the upper end of the bag in response to a discharge completion signal is disposed in the rear stage.
The control means includes
Each time the discharge process is performed, a discharge notification process for outputting the discharge completion signal to the packaging machine at a predetermined second timing is performed.
2. The combination weigher according to claim 1, wherein when the overload hopper is included in the discharge combination, a timing for outputting the discharge completion signal in the discharge notification process is set to be later than the second timing. The control means, when the overload hopper is included in the discharge combination,
The gate full open time longer than the predetermined time based on a gate full open time calculation formula for calculating a gate full open time that is a time for the overload hopper to maintain the gate full open state using the weight ratio of the overload hopper And opening and closing the gate of the excess hopper based on the calculated gate full open time,
The discharge notification time is calculated based on a discharge notification time calculation formula for calculating a discharge notification time that is a time from a predetermined time point to an output start time point of the discharge completion signal using the weight ratio of the excess hopper. The combination weigher according to claim 2, configured to output the discharge completion signal based on the calculated discharge notification time. The control means includes
Storage means for storing the weight of the overweight hopper when it is a weighing hopper for weighing the weight of the overweight hopper held in the discharge combination,
The overweight hopper is included in the discharge combination currently determined, the overweight hopper is the weighing hopper, and the weight of the object to be weighed held in the overweight hopper is stored in the storage means in the past When the object to be weighed is discharged from the hopper selected for the currently determined discharge combination and the new object to be weighed is not supplied to the excess hopper It is determined whether or not an object to be weighed remains in the overload hopper based on the measurement value of the overload hopper, and when it is determined that the object is remaining, the gate fully open time calculated for any of the weight ratios The combination weigher according to claim 3, wherein the combination weigher is configured to correct the gate full-open time calculation formula so as to be longer. The packaging machine
When the upper end of the bag is sealed, when the bite of the object to be weighed occurs in the sealed portion, it is configured to output a biting detection signal to the control means,
The control means includes
When the bite detection signal is input from the packaging machine when the object to be weighed is discharged from the hopper selected as the discharge combination including the overload hopper, the discharge calculated for any of the weight ratios The combination weigher according to claim 3, configured to correct the discharge notification time calculation formula so that the notification time becomes longer. A combination weigher and a packaging machine that is arranged at the rear stage of the combination weigher, and in which a weighing object discharged from the combination weigher is supplied into the bag and seals the upper end of the bag in response to a discharge completion signal Prepared,
The combination weigher is
A plurality of hoppers having a discharge gate for holding the supplied objects to be weighed and discharging the objects to be weighed;
A combination process for obtaining one discharge combination composed of a combination of the hoppers in which the total weight of the objects to be weighed is within an allowable range with respect to the target weight, and the discharge combination is selected at a predetermined first timing. A discharge process for discharging the object to be weighed from the hopper by closing the discharge gate after maintaining the gate fully open state for a predetermined time after the discharge gate of the hopper being opened is fully opened. Control means for repeatedly performing discharge notification processing for outputting the discharge completion signal to the packaging machine at a predetermined second timing each time it is performed;
A collecting chute disposed below the plurality of hoppers, for collecting the objects to be weighed discharged from the hoppers, and discharging them from the discharge port provided at the lower part to the packaging machine,
The control means is configured so that each time the combination process is performed, a hopper whose weight ratio, which is a ratio of the weight of the objects to be weighed with respect to the target weight, exceeds a predetermined ratio (hereinafter referred to as “overweight hopper”) is discharged. It is determined whether it is included in a combination, and when the overload hopper is included, the time during which the overload hopper maintains the gate fully open state when performing the discharge process is set to be longer than the predetermined time, and The timing for outputting the discharge completion signal in the discharge notification process is configured to be later than the second timing.
Weighing packaging system.

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