JP5723196B2 - Combination scale - Google Patents

Description

  The present invention relates to a combination weigher for weighing objects to be weighed such as vegetables, fruits or confectionery.

  Generally, objects to be weighed such as vegetables and fruits that have been weighed with a combination weigher to have a predetermined weight are packaged by a packaging machine, for example.

  FIG. 9 is a diagram schematically showing a schematic configuration of a conventional combination weigher of Patent Document 1. As shown in FIG.

  In this combination weigher, an object to be weighed is supplied from a supply device 30 to the central portion of a conical top cone 31a of a main feeder (dispersion feeder) 31, and the main feeder 31 feeds the object to be weighed toward the periphery by vibration. Then, it is conveyed to a plurality of tray-like linear feeders 32 that are radially installed around the main feeder 31.

  A vibration device is attached to the plurality of linear feeders 32, and each linear feeder 32 is vibrated to convey an object to be weighed and put into the plurality of supply hoppers 33. The plurality of supply hoppers 33 temporarily hold the objects to be weighed, open the input gate 34, and load the objects to be weighed into the weighing hoppers 35 disposed below the supply hopper 33. In each weighing hopper 35, the weight of the object to be weighed is measured by the weight sensor 36, and a control unit (not shown) performs a combination operation based on the measured value, so that the total of the measured values matches the combined target weight. A combination of the weighing hoppers 35 of the closest predetermined weight range is obtained, the discharge gate 37 of the weighing hopper 35 selected by this combination is opened, the objects to be weighed are discharged, and the packaging machine 39 is connected via the collecting chute 38. And packaging with a packaging machine 39.

JP 62-1113024 A

  When such a combination weigher is used to produce a packed product containing several pieces by performing a combination weighing of an object to be weighed that has a large surface friction resistance such as bell pepper and is difficult to slip, the main feeder 31 has a certain amount. The supply of the object to be weighed to the linear feeder 32 may be hindered.

  FIG. 10 is a plan view schematically showing five linear feeders 32 (1) to 32 (5) among the conical top cone 31 a of the main feeder 31 and the plurality of tray-like linear feeders 32.

  In the vicinity of the boundary portion between the peripheral edge portion of the conical top cone 31a of the main feeder 31 and the carry-in end of each tray-like linear feeder 32, for example, the number of times selected for the combination within the predetermined weight range is large, and the measurement is performed. In the vicinity A near the carry-in end of a certain linear feeder 32 (3) where the object 20a is supplied to the supply hopper 33 and the object to be weighed 20a is reduced, the linear feeders 32 (2) and 32 (4) on both sides are close to each other. The objects to be weighed 20a stay and overlap to form a so-called bridge, and the carry-in end of a certain linear feeder 32 (3) is blocked by the bridge, so that the object to be weighed into the certain linear feeder 32 (3) is obtained. 20a may not be supplied.

  In such a case, the weighing object 20a cannot be supplied from the certain linear feeder 32 (3) to the corresponding supply hopper 33 (3), and accordingly, the corresponding weighing hopper is supplied from the supply hopper 33 (3). 35 (3), the object to be weighed 20a cannot be input, the number of effective hoppers that can participate in the combination calculation is reduced, the combination accuracy is continuously lowered, and the yield is deteriorated. Further, when the combination of the weighing hoppers within the predetermined weight range is impossible, it causes a decrease in the weighing speed.

  The present invention has been made in view of the above-described points, and an object of the present invention is to eliminate a continuous decrease in combination accuracy caused by the occurrence of a bridge that hinders the supply of objects to be weighed. And

  In order to achieve the above object, the present invention is configured as follows.

(1) A combination weigher according to the present invention includes a dispersion unit that disperses an object to be weighed and dropped from a supply device to the surroundings, and an object to be weighed that is arranged around the dispersing unit and dispersed by the dispersing unit. A plurality of conveying sections that respectively convey and discharge from the conveying end, and are arranged corresponding to the respective conveying sections, hold the objects to be discharged from the conveying end, and move the held objects to be measured downward A plurality of supply units to be supplied, a plurality of measurement units that are arranged corresponding to the respective supply units, hold the objects to be weighed supplied from the respective supply units, and measure the weight of the held objects to be weighed; An operation control unit that controls the supply unit to drop and supply the objects to be weighed to the dispersion unit and the transport unit, and that performs a combination operation based on the measurement values of the objects to be weighed by the weighing unit. A combination scale,
A weighing object sensor for detecting a weighing object at each conveyance end of each conveyance unit and providing a detection output to the calculation control unit;
The arithmetic control unit controls the supply device when the detection output continues a non-detection state in which an object to be weighed is not detected over a predetermined period when the conveyance unit is driven. Then, the object to be weighed is dropped and supplied from the supply device to the dispersing portion.

  The case where the transport unit is driven means, for example, the case where the transport unit is continuously driven, or the case where the transport unit is repeatedly driven over a set time.

  The predetermined period is a period for accurately determining that the cause that the detection output of the object sensor continues the non-detection state is due to the bridge. In other words, even when no bridge is generated, depending on the type of the objects to be weighed, when the objects to be weighed are transported by the transport unit, adjacent objects to be weighed are not continuously transported but spaced apart. May be transported. In such a case, when the portion corresponding to the interval is located at the transport end of the transport unit, the detection output of the object sensor is in a non-detection state in which the object is not detected. This is to prevent erroneous determination that a bridge has occurred based on the detection output.

  Therefore, the predetermined period is preferably determined in consideration of the type of the object to be weighed, the transport distance of the transport unit, and the like, and the object to be weighed supplied from the dispersion unit to the transport unit reaches the transport end of the transport unit. It is good also as a period required for conveyance.

  This predetermined period may be defined by, for example, the number of weighing cycles, may be defined as the number of times of driving the conveyance unit that is driven over a set time, or the setting You may prescribe | regulate as many times of time.

  According to the combination weigher of the present invention, the calculation control unit that controls the driving of the conveyance unit is provided with the detection output of the weighing object sensor that detects the weighing object at each conveyance end of each conveyance unit. Whether or not the object to be weighed is transported to the transport end can be ascertained by driving.

  For example, in the vicinity of the boundary portion between the peripheral edge of the dispersing unit and the carry-in end of a certain transport unit, the object to be weighed stays to form a bridge, and when the object to be weighed cannot be supplied to the certain transport unit, Since there is no object to be weighed in a certain transport unit and the object to be weighed cannot be transported to the transport end, it can be grasped. Therefore, in such a case, since a bridge is generated, the object to be weighed is supplied to the dispersing unit by dropping, and the bridge is broken by the impact when the object to be weighed is dropped from the dispersing unit. It is possible to supply an object to be weighed to a certain transport unit. As a result, it is possible to eliminate a continuous decrease in combination accuracy and a decrease in measurement speed due to the bridge.

  (2) In a preferred embodiment of the combination weigher of the present invention, the combination weigher includes a detection unit that detects the amount of the object to be weighed in the dispersion unit, and the calculation control unit is configured to perform the dispersion based on a detection output of the detection unit. When the amount of the object to be weighed in the section becomes less than the lower limit value, the supply device is controlled to start dropping supply of the object to be weighed to the dispersing section. The apparatus is controlled to stop the supply of the object to be weighed to the dispersing unit.

  According to this embodiment, the calculation control unit starts supplying the objects to be weighed by the supply device when the amount of the objects to be weighed in the dispersing unit becomes less than the lower limit value based on the detection output of the detecting unit. When the upper limit value is exceeded, the supply of the object to be weighed by the supply device is stopped, so that the amount of the object to be weighed in the dispersion unit can be controlled within a predetermined range.

  (3) In the embodiment of the above (2), when the calculation control unit drives the transport unit, the detection output of the measurement object sensor is in a non-detection state where the measurement object is not detected. When continuing for the predetermined period, even if the amount of the object to be weighed in the dispersion unit is equal to or greater than the upper limit value, the supply device is controlled to transfer the object to be weighed from the supply device to the dispersion unit. You may make it supply by dropping.

  The supply of the objects to be weighed from the supply device to the dispersion unit is normally stopped when the amount of the objects to be weighed in the dispersion unit exceeds the upper limit value. When the non-detection state continues for the predetermined period, it is assumed that a bridge has occurred and the object to be weighed is forcibly supplied from the supply device to the dispersion unit regardless of the upper limit value. You can break the bridge.

  (4) In another embodiment of the combination weigher of the present invention, the calculation control unit detects that the object to be weighed has not been detected by the detection output of the object sensor when the transport unit is driven. When the state is continued for the predetermined period, the supply device is controlled from the supply device to the dispersion unit on condition that the amount of the object to be weighed in the dispersion unit is equal to or less than a predetermined amount. Drop and supply the object to be measured.

  The predetermined amount is preferably a small amount so as to increase the impact when dropping and supplying the object to be measured from the supply device to the dispersing portion, and may be a lower limit value in the embodiment of the above (2).

  According to this embodiment, when the detection output of the weighing object sensor continues the non-detection state over the predetermined period, the weighing object is immediately dropped and supplied from the supply device to the dispersion unit as a bridge occurs. Instead, on condition that the amount of the object to be weighed in the dispersion part is equal to or less than the predetermined amount, for example, when the amount of the object to be weighed in the dispersion part is larger than the predetermined amount, the amount is decreased to the predetermined amount. The weighing object can be dropped and supplied from the supply device to the dispersion unit, and the impact energy due to the drop can be reduced compared to the case where the measurement object is dropped and supplied with a large amount of the weighing object in the dispersion unit. You can break up the bridge effectively.

  (5) In another embodiment of the combination weigher of the present invention, the calculation control unit detects the object to be weighed when the detection output of the object sensor detects the object when the transport unit is driven for a set time. When it is in a non-detection state, the transport unit is further driven until the detection output of the object sensor shifts to a detection state in which the object is detected.

  When the transport unit is further driven, it is preferable to continue the drive following the drive for the set time, but the drive for the set time may be temporarily stopped and driven again.

  When the transport unit is driven for a set time, the object to be weighed at the transport end of the transport unit is supplied to the supply unit, and a new object to be weighed is transported to the transport end. Although it should be in the detection state, for example, depending on the type of the objects to be weighed, when being transported by the transport unit, adjacent objects to be weighed are not transported continuously but transported at intervals. In such a case, when the portion corresponding to the interval is located at the transport end of the transport unit, the detection output of the object sensor becomes a non-detection state in which the object to be weighed is not detected. If driving of the transport unit is stopped in this state, the object to be weighed cannot be supplied to the supply unit even if the transport unit is driven for the next set time. May not be able to be charged.

  According to this embodiment, when the transport unit is driven for a set time and the detection output of the object sensor is in the non-detection state, the transport unit is further driven until the detection state is entered, It is possible to stop the driving of the transport unit in a state where the product has been transported to the transport end, and then to drive the transport unit over a set time, thereby allowing the object to be weighed into the supply unit.

  According to the present invention, the object to be weighed stays in the vicinity of the boundary portion between the peripheral edge of the dispersion part and the carry-in end of the certain conveying part, and a bridge is formed so that the object to be weighed is not supplied to the certain conveying part. In such a case, since it can be grasped based on the detection output of the weighing object sensor for detecting the weighing object at the conveyance end of the conveyance unit, in such a case, from the supply device to the dispersion unit The fall of the object to be weighed is dropped, and the bridge is broken by the impact at the time of dropping, so that the object to be weighed can be supplied to the certain conveyance unit, and thereby the continuous combination accuracy caused by the bridge In addition, a decrease in weighing speed can be eliminated.

FIG. 1 is a schematic diagram showing a schematic configuration of a combination weigher according to an embodiment of the present invention. FIG. 2 is a block diagram showing a schematic configuration of the combination weigher of FIG. FIG. 3 is a flowchart for explaining the operation of the combination weigher. FIG. 4 is a flowchart showing details of the supply device control of FIG. FIG. 5 is a flowchart showing details of the linear feeder control of FIG. FIG. 6 is a flowchart showing details of the linear feeder control of FIG. FIG. 7 is a time chart for explaining the operation of the combination weigher of FIG. FIG. 8 is a schematic diagram showing a schematic configuration of a combination weigher according to another embodiment of the present invention. FIG. 9 is a schematic configuration diagram of a conventional combination weigher. FIG. 10 is a plan view schematically showing the main feeder and some linear feeders.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a schematic diagram showing a schematic configuration of a combination weigher according to an embodiment of the present invention. The combination weigher of this embodiment has a conical top cone 3 that radially disperses the objects 20 to be weighed and dropped from the supply device 1 at the center of the upper portion of the device, and a main that vibrates the top cone 3. A feeder (distributed feeder) 4 is provided.

  The object to be weighed 20 is not limited, but is suitable for weighing vegetables such as peppers, tomatoes and potatoes, fruits such as oranges and apples, or confectionery packed in pillows, and in particular, combination weighing. It is suitable for manufacturing a net packaged product or the like containing several pieces.

  The supply device 1 conveys an object to be weighed 20 such as bell pepper supplied from a belt conveyor (not shown) by vibration and drops it to the center of the top cone 3 to supply. In the top cone 3, the object to be weighed 20 supplied from the supply device 1 to the central portion thereof is conveyed toward the peripheral portion by vibration. Around the top cone 3, a plurality of linear feeder pans 6 for conveying the objects 20 to be weighed sent from the top cone 3 to a plurality of supply hoppers 12 and a plurality of linear feeder pans 6 for vibrating the linear feeder pans 6. Feeders 8 are provided radially. A plurality of supply hoppers 12 serving as supply units are provided below the peripheral edge of the linear feeder pan 6, and a weighing hopper 13 serving as a weighing unit is provided below the supply hopper 12. It is arranged in a circle.

  Under the supply hopper 12 and the weighing hopper 13, a closing gate 12 a and a discharging gate 13 a that can be opened and closed are respectively provided. The supply hopper 12 receives the object 20 to be weighed 20 which is transported by the linear feeder pan 6 and dropped and discharged from the transport end 6a which is the front end thereof. 12a is opened, and the object 20 is dropped and discharged and put into the weighing hopper 13. Each weighing hopper 13 is connected to a weight sensor 10 such as a load cell for measuring the weight of the object 20 in the weighing hopper 13, and a measured value from each weight sensor 10 is output to the control device 9.

  The plurality of linear feeder pans 6 and the plurality of linear feeders 8 that respectively vibrate the respective linear feeder pans 6 constitute a plurality of transport units that transport the objects to be weighed 20 to the corresponding supply hoppers 12.

  The weighing hopper 13 can discharge the objects 20 to the collecting chute 14. When a combination of the weighing hoppers 13 from which the objects to be weighed 20 are to be discharged is obtained from the plurality of weighing hoppers 13 by the combination calculation by the control device 9, and a discharge request signal is input from the packaging machine 15, the combination is applicable. The objects 20 to be weighed are discharged from the weighing hopper 13 to the collecting chute 14 and further discharged to the lower packaging machine 15.

  In this embodiment, the amount of the weighing object supplied from the supply device 1 to the top cone 3 is measured by the top cone weight sensor 5 supporting the top cone 3 and the main feeder 4, and the measured value is controlled. It is given to the device 9. In the control device 9, based on the weight of the weighing object 20 on the top cone 3 measured by the top cone weight sensor 5, the amount of the weighing object 20 on the top cone 3 is kept within a preset range. Thus, the supply device 1 is controlled. That is, based on the detection output of the top cone weight sensor 5, the control device 9 drives the supply device 1 to supply when the amount of the weighing object 20 on the top cone 3 becomes less than the lower limit value. Is started, and when the value exceeds the upper limit value, the driving of the supply device 1 is stopped to stop the supply operation. The lower limit value and the upper limit value are set in advance by operating the operation setting display unit 11.

  Furthermore, in this embodiment, as will be described later, the object to be weighed 20 stays in the vicinity of the boundary between the peripheral edge of the top cone 3 and the carry-in end of a certain linear feeder pan 6, and a bridge is generated. When it is determined that the object to be weighed 20 is not supplied to the linear feeder pan 6, the object to be weighed 20 is forcibly dropped from the supply device 1 to the top cone 3 and is weighed from the supply device 1 onto the top cone 3. The bridge is broken by using an impact when the object 20 is dropped and supplied.

  The operation setting display unit 11 is configured using, for example, a touch panel or the like, and performs operation of the combination weigher, setting of operation parameters thereof, and the like, and displays an operation speed, a combination measurement value, and the like on a screen.

  The control device 9 performs operation control of the supply device 1 and overall operation of the combination weigher, and performs combination calculation. In the combination calculation, the weight of the weighing object 20 in the weighing hopper 13 is measured by the weight sensor 10, and the measured value is set as the weight of the weighing object 20 in the weighing hopper 13. From the plurality of weighing hoppers 13, one combination is obtained in which the combined weight that is the sum of the weight values of the objects to be weighed 20 is equal to the combined target weight or the closest weight within the allowable range.

  In the case where the object to be weighed 20 is an object having a large surface frictional resistance such as bell pepper and not slippery, the peripheral edge of the top cone 3 of the main feeder 4 and the carry-in end of a certain linear feeder pan 6 are used. In some cases, the object to be weighed 20 stays in the vicinity of the boundary portion to cause a bridge. When such a bridge occurs, the supply of the weighing object 20 to the certain linear feeder pan 6 is hindered, and the weighing object 20 cannot be conveyed, and as a result, corresponds to the certain linear feeder pan 6. The weighing object 20 is not supplied to the supply hopper 12, the weighing object 20 cannot be put into the corresponding weighing hopper 13 from the supply hopper 12, and the number of weighing hoppers 13 that can participate in the combination calculation is reduced. The accuracy will be continuously reduced.

  Therefore, in this embodiment, when it is determined that a bridge has occurred, the object to be weighed 20 is forcibly supplied from the supply device 1 to the top cone 3 to be supplied to the top cone 3 from the supply device 1. The bridge is broken by an impact caused by the drop of the weighing object 20.

  For this reason, in this embodiment, a plurality of objects to be weighed 7 that respectively detect the objects to be weighed 20 at the conveying end 6a that is the tip of each of the plurality of linear feeder pans 6 are provided. 7, when the non-detected state in which the workpiece 20 is not detected at the transport end 6 a of the linear feeder pan 6 continues as described later, a bridge is generated and the transport end 6 a of the linear feeder pan 6 is covered. Assuming that the object to be weighed 20 is not transported, the drop object 20 is forcibly supplied from the supply device 1 to the top cone 3.

  In this embodiment, for example, a photoelectric sensor is used as the weighing object sensor 7 that detects the weighing object 20, but the photoelectric sensor is not limited, and an image captured by a weight sensor such as a load cell, a limit switch, or a camera is used. Other sensors such as an image sensor to be processed may be used.

  FIG. 2 is a block diagram showing a schematic configuration of the control system of the combination weigher in this embodiment, and the same reference numerals are given to the portions corresponding to FIG.

  As shown in FIG. 2, the control device 9 includes a CPU unit 16 as an arithmetic control unit, a memory unit 17, an A / D conversion circuit unit 18, a gate drive circuit unit 19, a vibration control circuit unit 21, An I / O circuit unit 22 connected to the packaging machine 15 and an I / O circuit unit 25 to which a detection output of the object sensor 7 is given.

  The CPU unit 16 serving as a calculation control unit controls each unit and performs a combination calculation. The memory unit 17 stores an operation program for the combination weigher, operation parameters to be set, and the like, and serves as a work area for operations on the CPU unit 16. The A / D conversion circuit unit 18 includes a weight sensor 5 for detecting the weight of the weighing object 20 on the top cone 3 and a weight sensor 10 for detecting the weight of the weighing object 20 of each weighing hopper 13. The analog signal is converted into a digital signal and output to the CPU unit 16. The CPU 16 is also provided with detection output from the above-mentioned object sensor 7 for detecting the object 20 to be measured at the conveyance end 6 a of each linear feeder pan 6 via the I / O circuit unit 25.

  The gate drive circuit unit 19 controls the opening / closing of the supply gate 12 a of the supply hopper 12 and the discharge gate 13 a of the weighing hopper 13 based on a control signal from the CPU unit 16. The vibration control circuit unit 21 controls each vibration operation of the supply device 1, the main feeder 4, and each linear feeder 8 based on a control signal from the CPU unit 16. The CPU unit 16 is connected so as to be able to communicate with the operation setting display unit 11.

  The control device 9 controls the operation of the supply device 1 and the entire combination weigher by the CPU unit 16 executing the operation program stored in the memory unit 17.

  In the combination weigher, it is necessary to set a large number of operation parameters for performing the operation as described above, and the setting is performed by the operator using the operation setting display unit 11, and the value of the set operation parameter is the CPU unit. 16 and stored in the memory unit 17. The operation parameter includes a combination target weight which is a target value in the combination calculation and an allowable range thereof, vibration amplitude and driving time (one vibration duration time) of each of the feeders 4 and 8, the predetermined number of times described above, and the like.

  FIG. 3 is a flowchart for explaining the entire processing operation of the combination weigher of this embodiment.

  First, the control device 9 performs ON / OFF control of the supply device 1 based on the detection output of the top cone weight sensor 5 to control the supply amount of the object 20 to be measured on the top cone 3. (Step s1).

  Next, the main feeder control for supplying the object 20 to the linear feeder pan 6 by controlling the driving of the main feeder 4 for vibrating the top cone 3 to disperse the object 20 on the top cone 3 to the surroundings is performed. (Step s2).

  Next, the driving of the linear feeder 8 that vibrates the linear feeder pan 6 is controlled, and the linear feeder pan 6 corresponding to the empty supply hopper 12 is vibrated so that the weighing object 20 on the linear feeder pan 6 is moved to the empty feeder hopper 6. Linear feeder control for supplying to the supply hopper 12 is performed (step s3).

  Next, the process proceeds to the supply hopper control in step s4. In this supply hopper control, the input gate 12a of the supply hopper 12 corresponding to the empty weighing hopper 13 is opened, the object 20 is input to the empty measurement hopper 13, and the process proceeds to step s5.

  In step s5, when the weighing object 20 is inserted into the weighing hopper 13, the weight of the weighing object 20 charged into the weighing hopper 13 is measured by the corresponding weight sensor 10, and the measured value is sent to the control device 9. Perform the weighing control.

  Next, based on the weight of the weighing object 20 put in the weighing hopper 13, combination calculation is performed, and whether the combined weight, which is the total weight of various weights of the weighing object 20, is equal to the combination target weight? Alternatively, an optimum combination that is a combination of the weighing hoppers 13 that is heavier than the combination target weight and close to the combination target weight is selected (step s6).

  Thereafter, it is determined whether or not a discharge command signal is input from the packaging machine 15 (step s7), and when a discharge command signal is input, the discharge of the weighing hopper 13 of the optimum combination selected by the combination calculation is performed. Weighing hopper control for opening the gate 13a and discharging the object 20 to be weighed is performed (step s8), and the process returns to step s1. Thereafter, the weighing object 20 of the optimum combination is discharged to the packaging machine 15 by repeating the same weighing cycle as described above.

  FIG. 4 is a flowchart showing details of the supply device control in step s1 of FIG.

  First, it is determined whether or not the supply device forced drive flag is on (step s100). This supply device forcible drive flag is a flag for forcibly supplying the object 20 to be weighed from the supply device 1 onto the top cone 3 when it is determined that a bridge has occurred as will be described later.

  When this supply device forced drive flag is on, a bridge has occurred, and the supply device is forcibly driven on the assumption that the object to be weighed 20 should be dropped and supplied onto the top cone 3 from the supply device. Is turned on (step s101), the forced drive timer is set to start measurement of the forced drive time (step s102), the drive signal for the supply device 1 is turned on, and the supply device 1 is turned on. The to-be-measured object 20 is dropped and supplied to the top cone 3 by forcibly driving (step s103), the supply device forcible driving flag is turned off, and the process ends (step s104).

  In step s100, when the supply device forced flag is not turned on, it is determined whether or not the supply device forced drive flag is turned on (step s105). When the supply device forced drive flag is turned on, the supply device 1 is forcibly driven. Assuming that the time is within, the forced drive timer for measuring the forced drive time is subtracted (step s106), and it is determined whether or not the time is up (step s107).

  In step s107, when the time is up, the drive signal to the supply device 1 is turned off to stop the forced supply operation of the weighing object 20 by the supply device 1 (step s108), and the supply device forced drive flag is turned off. (Step 109). If the time is not up in step s107, the process ends.

  In step s105, when the supply device forced drive flag is not turned on, the weight value of the object 20 on the top cone 3 is read by the top cone weight sensor 5 (step s110), and the supply device 1 performs normal supply. It is determined whether or not the supply device driving flag indicating that the operation is in progress is on (step s111). If the flag is on, it is determined whether or not the measured value is equal to or higher than the upper limit value (step s115). ), When the value is equal to or greater than the upper limit value, the drive signal to the supply device 1 is turned off to stop the normal supply operation of the weighing object 20 by the supply device 1 (step s116), and the supply device driving flag is turned off to end the operation. (Step s117). In step s115, when the measured value is not greater than or equal to the upper limit value, the process ends.

  In step s111, when the supply device driving flag is not turned on, it is determined whether or not the measured value is less than the lower limit value (step s112). When the measured value is less than the lower limit value, the drive signal for the supply device 1 is turned on. Then, the normal supply operation of the object to be weighed 20 by the supply device 1 is started (step s113), and the supply device driving flag is turned on to end the operation (step s114). In step s112, when the measured value is not less than the lower limit value, the process ends.

  5 and 6 are flowcharts showing details of the linear feeder control in step s3 of FIG.

  First, the number k for specifying the plurality of linear feeders 1 to n is set to an initial value “1” (step s301). Next, it is determined whether or not the drive flag of the linear feeder 8 (k) is turned on (step s302). The drive flag of the linear feeder 8 is set for the linear feeder 8 corresponding to the supply hopper 12 that has been emptied by putting the object 20 into the weighing hopper 13 in the supply hopper control (step s4) of FIG. Is done. When the drive flag of the linear feeder 8 (k) is on, the drive time timer of the linear feeder 8 (k) is set and measurement of the drive time is started (step s303), and the linear feeder 8 (k) The driving flag is turned on (step s304), the driving of the linear feeder 8 (k) is started, and the process proceeds to step s306 in FIG. 6 (step s305).

  In step s306 in FIG. 6, the weighing object sensor 7 (k) that detects the weighing object 20 at the conveyance end 6a of the linear feeder pan 6 (k) corresponding to the linear feeder 8 (k) detects the weighing object. If it is detected, the detection flag of the linear feeder 8 (k) is turned on (step s307), the count value of the detection counter (k) is reset to “0”, and the process returns to step s324. Move. In step s306, when the object to be weighed is not detected by the object sensor 7 (k), the detection flag of the linear feeder 8 (k) is turned off, and the process proceeds to step s324. As described above, the detection flag corresponds to ON (detection state) or OFF (non-detection state) of the detection output of the weighing object sensor 7 (k) corresponding to the linear feeder 8 (k). The detection counter is a counter for detecting whether or not the detection output of the weighing object sensor 7 (k) corresponding to the linear feeder 8 (k) continues the non-detection state for a predetermined period. In s307, since the detection flag is on (detected state), the count value is reset in step s308.

  Referring to FIG. 5 again, in step s302, when the driving flag of linear feeder 8 (k) is not turned on, a driving flag indicating that linear feeder 8 (k) is being driven is turned on. (Step s310), and if not turned on, the process proceeds to step s324 in FIG.

  In step s310, when the driving flag indicating that the linear feeder 8 (k) is being driven is turned on, it is determined whether or not the detection flag of the linear feeder 8 (k) is turned on (step s311). ). When the detection flag of the linear feeder 8 (k) is on, the process proceeds to step s315 in FIG.

  If the detection flag of the linear feeder 8 (k) is not turned on in step s311, it is determined whether or not the weighing object sensor 7 (k) corresponding to the linear feeder 8 (k) has detected the weighing object. If it is detected (step s312), the detection flag of the linear feeder 8 (k) is turned on to reset the count value of the detection counter (k) to “0”, and the process proceeds to step s315 in FIG. In step s312, when the weighing object sensor 7 (k) does not detect the weighing object, the process proceeds to step s315 in FIG.

  In step s315 of FIG. 6, a timer for measuring the driving time of the linear feeder 8 (k) is subtracted to determine whether or not the time is up (step s316). When the time is up, the linear feeder 8 (k) It is determined whether or not the detection flag is on (step s317). When the detection flag is on, the driving flag of the linear feeder 8 (k) is turned off (step s322), and the linear feeder 8 (k) is driven. Stop and move to step s324.

  In step s317, when the detection flag of the linear feeder 8 (k) is not turned on, the detection output of the weighing object sensor 7 (k) corresponding to the linear feeder 8 (k) even if driving for a set time is performed. Is a non-detected state (off) in which the object 20 is not detected, that is, the object 20 is measured at the conveying end 6a (k) of the linear feeder pan 6 (k) corresponding to the linear feeder 8 (k). Therefore, the drive time timer of the linear feeder 8 (k) is set to extend the drive time (step s318), and the count value of the detection counter of the linear feeder 8 (k) is incremented by 1 (step s319). It is determined whether or not the count value of the detection counter has reached a predetermined number, for example, 3 or more (step s320).

  In step s320, when the count value of the detection counter becomes 3 or more, the detection flag is turned off over a period of time that is three times the set driving time of the linear feeder 8 as a predetermined period. The detection output of the object sensor 7 (k) continues in the non-detection state (off), and it is determined that a bridge has occurred. The supply device forced drive flag in FIG. 4 is turned on, and the process proceeds to step s324. In step s320, when the count value of the detection counter is not 3 or more, the process proceeds to step s324.

  In step s324, the number k is incremented by 1, and it is determined whether or not the number k is n + 1 (step s325). If not, the process returns to step s302 and the same processing is performed for the next linear feeder 8. To do. In step s325, when n + 1 is reached, the process ends.

  FIG. 7 shows an example of a time chart used for explaining the operation of this embodiment. FIG. 7A shows the level of the measured value of the object 20 measured by the top cone weight sensor 5. ) Shows the driving state of the feeding device 1, FIG. 5C shows the driving state of the main feeder 4, and FIG. 4D shows the first (k = 1) of the plurality of linear feeders 1 to n. The detection output of the weighing object sensor 7 (1) corresponding to the linear feeder 8 (1), FIG. 9 (e) shows the driving state of the first linear feeder 8 (1), and FIG. The detected output of the weighing object sensor 7 (n) corresponding to the (k = n) linear feeder 8 (n) shows the drive of the nth (k = n) linear feeder 8 (n). (H) shows the driving state of the feeding gate 12a of the supply hopper 12, and (i) shows the driving state of the discharging gate 13a of the weighing hopper 13. (j) shows the discharge command signal from the packaging machine 12, respectively.

  FIG. 7 shows an example in which a bridge is generated near the carry-in end of the linear feeder pan 6 (1) vibrated by the first linear feeder 8 (1) shown in FIG.

  In response to the discharge command signal from the packaging machine 15 shown in FIG. 6 (j), the discharge gate 13a of the weighing hopper 13 selected by the combination calculation is opened (ON) as shown in FIG. ) And the weighing object 20 is discharged to the packaging machine 15. In response to the opening operation of the discharge gate 13a of the weighing hopper 13, the input gate 12a of the supply hopper 12 corresponding to the weighing hopper 13 discharged from the weighing object 20 is empty. As shown in h), it is opened (turned on) and the object 20 to be weighed is put into the weighing hopper 13.

  In response to the opening operation of the supply gate 12a of the supply hopper 12, the linear feeder 8 corresponding to the supply hopper 12 which has been emptied by inputting the object 20 into the measurement hopper 13, for example, FIG. ), (G) linear feeders 8 (1), 8 (n) are driven over the driving time. The main feeder 4 shown in FIG. 3C is driven in synchronization with the linear feeder 8.

  Before the linear feeders 8 (1) and 8 (n) are driven, the weighing object sensors 7 (1) and 7 (n) corresponding to the linear feeders 8 (1) and 8 (n) Since the objects 20 to be weighed at the respective transport ends 6a (1) and 6a (2) of the feeder pans 6 (1) and 6 (2) are detected, as shown in FIGS. The detection output is ON corresponding to the detection state. In addition, after the driving of the linear feeders 8 (1) and 8 (n) is started, the feed ends 6a (1) and 6a (n) of the linear feeder pans 6 (1) and 6 (n) are covered. Since the weighing object 20 is dropped and supplied to the supply hopper 12 and the objects to be weighed 20 do not exist at the transport ends 6a (1) and 6a (n), the objects to be weighed as shown in FIGS. The detection outputs of the weighing object sensors 7 (1) and 7 (n) are turned off corresponding to the non-detection state.

  In the linear feeder 8 (n) shown in FIG. 6 (g) in which no bridge is generated, the feeding end 6a (n) of the linear feeder pan 6 (n) is newly provided by the driving for the set driving time T1. Since the object to be weighed 20 is transported, the detection output of the object to be weighed sensor 7 (n) is turned on to detect the new object to be weighed 20 and indicate the detection state, as shown in FIG. Become. In this way, when the bridge is not generated and the object to be weighed 20 is continuously conveyed through the linear feeder pan 6 (n), as shown in FIGS. Every time 8 (n) is driven over the driving time T1, the weighing object 20 at the conveying end 6a (n) of the linear feeder pan 6 (n) is dropped and supplied to the supply hopper 12, and a new weighing object is obtained. As a result of 20 being conveyed to the conveyance end 6a (n), the detection output of the object sensor 7 (n) changes from the ON state corresponding to the detection state to the OFF state corresponding to the non-detection state, and then returns to the detection state. The corresponding on state is entered.

  On the other hand, in the linear feeder 8 (1) shown in FIG. 5 (e), the object sensor 7 (1) of the weighing object sensor 7 (1) can be driven as shown in FIG. The detection output continues to be in the off state while shifting from the on state corresponding to the detection state to the off state corresponding to the non-detection state. That is, the new object 20 is not conveyed to the conveyance end 6a (1) of the linear feeder pan 6 (1). Therefore, as shown in FIG. 5E, the driving time T1 of the linear feeder 8 (1) is extended and the driving is continued.

  The objects 20 to be weighed on the linear feeder pan 6 are not always continuously conveyed between the objects to be weighed 20, and are not continuous depending on the supply status of the objects 20 to be weighed from the main feeder 4. Thus, there may be a gap between the front and rear objects 20 to be weighed. In such a case, even if the linear feeder 8 is driven over the driving time T1, if the portion corresponding to the interval is located at the transport end 6a of the linear feeder pan 6, the detection output of the object sensor 7 is Since the weighing object 20 is not detected, the new weighing object 20 is conveyed to the conveying end 6a (1) of the linear feeder pan 6 (1) of the linear feeder 8 (1). The drive time T1 of the linear feeder 8 (1) is extended and the drive is continued.

  In FIG. 7, since a bridge is formed near the carry-in end of the linear feeder pan 6 (1) vibrated by the first linear feeder 8 (1) shown in FIG. 7 (e), the linear feeder 8 ( Even if the driving of 1) is continued, as shown in FIG. 4D, the detection output of the object sensor 7 (1) remains off corresponding to the non-detection state.

  Therefore, in this embodiment, even if the driving is continued over a predetermined period T2 (= T1 × 3), for example, three times the set driving time T1, the detection of the object sensor 7 (1) is performed. When the output remains off, it is determined that a bridge has occurred, and as shown in FIG. 5B, the supply device 1 is driven for a certain period T3 to forcibly supply the object 20 to be dropped. To do. The bridge is broken by an impact when the object 20 is forcibly dropped and supplied from the supply device 1 to the top cone 3.

  In FIG. 7, while the forced supply of the object to be weighed from the supply device 1 to the top cone 3 is performed three times, as shown in FIG. It is conveyed to the conveying end 6a (1) of the feeder pan 6 (1), and the detection output of the object sensor 7 (1) is turned on corresponding to the detection state. As a result, as shown in FIG. 9E, the driving of the linear feeder 8 (1) is stopped, the driving of the main feeder 4 is stopped, and the normal operation is resumed.

(Other embodiments)
In the above-described embodiment, if the detection output of the weighing object sensor 7 remains off even if the linear feeder 8 continues to be driven for a predetermined period, the supply device immediately determines that a bridge has occurred. 1 is driven to forcibly supply the object 20 to be weighed, but as another embodiment of the present invention, when it is determined that a bridge has occurred, the supply device 1 is immediately driven to measure the object to be weighed. Rather than supplying 20 by dropping, the apparatus waits until the amount of the object to be weighed 220 on the top cone 3 detected by the top cone weight sensor 5 falls to a predetermined amount, for example, the lower limit value, and reaches the lower limit value. Later, the supply device 1 may be driven to drop and supply the object 20 to be weighed. In this case, since the amount of the object to be weighed 20 on the top cone 3 is small, the impact when dropping the object to be weighed 20 from the supply device 1 is increased, and the bridge can be effectively broken.

  In the above-described embodiment, when it is determined that a bridge has occurred, the feeding device 1 is driven over a certain period of time to drop and feed the object 20 onto the top cone 3. However, as another embodiment of the present invention, When the bridge collapses and the detection output of the object sensor 7 does not turn on, until the amount of the object 20 on the top cone 3 reaches the upper limit value or until the limit value exceeding the upper limit value is reached. Alternatively, the supply device 1 may be driven to supply the object 20 to be dropped onto the top cone 3.

  Furthermore, as another embodiment of the present invention, as shown in FIG. 8, a flexible ring-shaped frame body 26 is installed so as to surround the periphery of the top cone 3, and the lower end of the frame body 26 is arranged. The number of objects 20 to be weighed transferred from the top cone 3 to the linear feeder pan 6 may be regulated by adjusting the installation height.

  When the object to be weighed 20 that easily rolls onto the top cone 3 from the supply device 1 is dropped and supplied by the frame body 26, the object to be weighed 20 rolls on the top cone 3 and is excessively supplied to the linear feeder pan 6. Can be prevented.

  In the above-described embodiment, the amount of the object 20 to be weighed on the top cone 3 is detected by the top cone weight sensor 5. However, as another embodiment of the present invention, instead of the weight sensor, above the top cone 3. For example, an ultrasonic type level detector is provided, and the level detector detects the amount of the object 20 on the top cone 3 and controls the amount of the object 20 on the top cone 3. Also good.

DESCRIPTION OF SYMBOLS 1 Supply apparatus 3 Top cone 4 Main feeder 5 Top cone weight sensor 6 Linear feeder pan 7 Weighing object sensor 8 Linear feeder 9 Control device 10 Weight sensor 12 Supply hopper 13 Weighing hopper 15 Packaging machine 16 CPU part 20 Weighing object

Claims (5)

A dispersion unit for dispersing the object to be weighed and dropped from the supply device to the surroundings;
A plurality of conveyance units that are respectively arranged around the dispersion unit and convey the objects to be weighed dispersed in the dispersion unit and discharge them from the conveyance end;
A plurality of supply units that are arranged corresponding to the respective conveyance units, hold the objects to be weighed discharged from the conveyance end, and supply the held objects to be weighed downward,
A plurality of measuring units arranged corresponding to each supply unit, holding the objects to be weighed supplied from each supply unit, and weighing the weight of the objects to be weighed;
An arithmetic control unit that controls the supply unit and the transport unit to drop and supply the objects to be weighed to the dispersion unit, and performs a combination operation based on the measurement values of the objects to be weighed by the measuring unit;
A combination weigher comprising:
A weighing object sensor for detecting a weighing object at each conveyance end of each conveyance unit and providing a detection output to the calculation control unit;
The arithmetic control unit controls the supply device when the detection output continues a non-detection state in which an object to be weighed is not detected over a predetermined period when the conveyance unit is driven. Drop and supply the objects to be weighed from the supply device to the dispersion unit.
A combination weigher characterized by that. A detection unit for detecting the amount of the object to be weighed in the dispersion unit;
The arithmetic control unit controls the supply device based on the detection output of the detection unit to control the supply device when the amount of the measurement object in the dispersion unit is less than a lower limit value. When the falling supply of the object is started and the upper limit value is exceeded, the supply device is controlled to stop the falling supply of the object to be weighed to the dispersion unit.
The combination weigher according to claim 1. The arithmetic control unit, when driving the transport unit, when the detection output of the object sensor continues a non-detection state in which the object to be measured is not detected over the predetermined period, Even if the amount of the object to be weighed in the dispersion unit is equal to or higher than the upper limit value, the supply device is controlled to drop and supply the object to be weighed from the supply device to the dispersion unit.
The combination weigher according to claim 2. The arithmetic control unit, when driving the transport unit, when the detection output of the object sensor continues a non-detection state in which the object to be measured is not detected over the predetermined period, On the condition that the amount of the object to be weighed in the dispersion unit is equal to or less than a predetermined amount, the supply device is controlled to drop and supply the object to be weighed from the supply device to the dispersion unit.
The combination weigher according to claim 1 or 2 . If the detection output of the object sensor is in a non-detection state in which the object to be weighed is not detected when the transport unit is driven for a set time, Until the detection output of is shifted to a detection state in which an object to be weighed is detected, further driving the transport unit;
The combination weigher according to claim 1.

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