JP4847094B2 - Combination scale - Google Patents

Description

  The present invention relates to a combination weigher that puts a weighed object into a packaging machine or the like.

  2. Description of the Related Art Conventionally, as a combination weigher that selectively discharges an object to be weighed from each weighing hopper to a different chute, for example, there is a structure as shown in FIG. 8 (see Patent Document 1).

  FIG. 8A is a schematic schematic view of a partial cross-section of a conventional combination weigher as viewed from the side, and FIG. 8B is a collective chute (inner chute and two outer chutes) of the same combination weigher. FIG. 8C is a schematic diagram of the two lower chutes, the intermediate hopper, and the discharge hopper of the combination weigher viewed from above.

  In this combination weigher, a conical dispersion feeder 1 is provided above the center substrate 5 to disperse the object to be weighed supplied from an external supply device radially by vibration. A plurality of linear feeders 2 are provided for feeding an object to be weighed sent from 1 to each supply hopper 3 by vibration. Below each linear feeder 2, a supply hopper 3 and a weighing hopper 4 are provided correspondingly, and the plurality of supply hoppers 3 and the weighing hoppers 4 are arranged in a circle around the center base 5. Each weighing hopper 4 is provided with a weight sensor 41 for measuring the weight of the object to be weighed in the weighing hopper 4. An inner chute 6a and two outer chutes 6b and 6c are disposed below the weighing hoppers 4 arranged in a circle. Each weighing hopper 4 is configured to selectively discharge the object to be measured to the inner chute 6a and the outer chute 6b or 6c below the weighing hopper 4. Intermediate hoppers 7a, 7b, 7c are disposed at the lower discharge ports of the inner chute 6a and the outer chutes 6b, 6c, respectively, and two discharge hoppers (8aL) are provided below the intermediate hoppers 7a, 7b, 7c. , 8aR), (8bL, 8bR), (8cL, 8cR). The intermediate hoppers 7a, 7b, and 7c are configured such that the objects to be weighed can be selectively discharged to the two lower discharge hoppers. A lower chute 9L is disposed below the discharge hoppers 8aL, 8bL, 8cL, and a lower chute 9R is disposed below the discharge hoppers 8aR, 8bR, 8cR. Under this combination weigher, for example, two wrapping machines or twin type wrapping machines are arranged, and the objects to be weighed discharged from the discharge ports 9La and 9Ra of the lower chutes 9L and 9R are respectively input to the packaging machine. It is thrown into the mouth.

The control unit 30 controls the operation of the entire combination weigher and performs combination processing. In the combination processing, combination calculation is performed based on the measurement value (measurement value by the weight sensor 41) of the group B weighing hopper 4 arranged above the one outer chute 6b, and the total of the measurement values of the measurement hopper 4 is the target. An optimum combination weighing hopper 4 that is within the allowable range for the weight value and that is closest to the target weight value (referred to as the combination hopper 4B) is selected, and the group C disposed above the other outer chute 6c is selected. A combination calculation is performed based on the measurement value of the weighing hopper 4, and the optimum combination weighing hopper 4 (referred to as a combination hopper 4C) is selected in the same manner. Then, out of the group A consisting of all the weighing hoppers 4, in the groups B and C, the combination calculation is performed based on the weighing values of the weighing hoppers 4 that are not selected as the optimum combination, and the weighing hoppers 4 ( This is designated as combination hopper 4A). The objects to be weighed are discharged simultaneously from the combination hoppers 4A, 4B, 4C selected by the above combination processing. The objects to be weighed in the group A combination hopper 4A are discharged to the inner chute 6a and temporarily held by the intermediate hopper 7a. The objects to be weighed in the group B combination hopper 4B are discharged to the outer chute 6b and temporarily held by the intermediate hopper 7b. Then, the objects to be weighed in the combination hopper 4C of group C are discharged to the outer chute 6c and temporarily held by the intermediate hopper 7c. Thereafter, the objects to be weighed are transferred from the three intermediate hoppers 7a, 7b, 7c to one discharge hopper 8aL, 8bL, 8cL at the same time. Similarly, the objects to be weighed held in the three intermediate hoppers 7a, 7b and 7c in the next weighing cycle are simultaneously transferred to the other discharge hoppers 8aR, 8bR and 8cR. Then, the discharge hoppers 8aL, 8bL, 8cL on the lower chute 9L side and the discharge hoppers 8aR, 8bR, 8cR on the lower chute 9R side perform the discharge operation alternately, so that each discharge is performed three times in two weighing cycles. The objects to be weighed are discharged from the outlets 9La and 9Ra.
Japanese Patent Publication No.8-1395

  According to the above-described conventional configuration, the optimum combination process for determining the combination hoppers 4A, 4B, and 4C for discharging the objects to be weighed to the respective chutes 6a, 6b, and 6c is discharged to each of the two outer chutes 6b and 6c. After selecting the combination weighing hopper 4 (combination hopper 4B, 4C), the optimum combination weighing hopper 4 (combination hopper 4A) to be discharged to the inner chute 6a is selected from the remaining unselected weighing hoppers 4. Therefore, the selection of these three sets of combination hoppers 4A, 4B, and 4C is not necessarily the best selection. For example, when considering the sum of the difference between the combination weight value and the target weight value, which is the sum of the weighing values of the weighing hoppers 4 selected for each of the combination hoppers 4A, 4B, and 4C, for example, in group B, the target The weighing hopper 4 having the second closest combination to the weight value is selected as the combination hopper 4B. In group C, the weighing hopper 4 having the second closest combination to the target weight value is selected as the combination hopper 4C, and the remaining weighing hoppers 4 are selected. When the weighing hopper 4 having the closest combination to the target weight value is selected as the combination hopper 4A, the combination weight values of the combination hoppers 4A, 4B, and 4C The total difference from the target weight value may be small. Therefore, in the conventional configuration described above, the overall combination weighing accuracy of the objects to be weighed discharged to the respective chutes 6a, 6b and 6c, which are discharge paths of the objects to be weighed, is not taken into consideration. There is room for improvement.

  The present invention has been made to solve the above-described problems, and in a combination weigher having a plurality of discharge paths, improvement of the combined weighing accuracy as a whole of the objects to be weighed discharged from the weighing hopper to the discharge paths. It aims at providing the combination scale which can aim at.

In order to solve the above-described problems, the combination weigher of the present invention measures the weight of each of the objects to be supplied and selectively discharges them in the first and second directions, Two or more first discharge paths that are provided corresponding to the weighing hoppers and to which the objects to be weighed discharged from the corresponding weighing hoppers in the first direction are transferred, and correspond to the plurality of weighing hoppers, respectively. One or more second discharge paths through which the objects to be weighed discharged from the corresponding weighing hoppers in the second direction are transferred, and control means, respectively, By classifying the weighing hoppers into groups corresponding to the discharge paths, the weighing hoppers belong to the two groups, and the groups are supplied to the weighing hoppers. A combination of weighing hoppers whose combined weight value, which is the sum of the weight values of the objects to be weighed, is within an allowable range with respect to the target weight value, is determined as an appropriate amount combination, and the appropriate amount combination of each of the groups is one by one A first process for obtaining an appropriate combination set that is combined and does not include the same weighing hopper in the appropriate combinations of the different groups to be combined; and each appropriate combination set obtained in the first process And calculating the sum of the difference between the combination weight value and the target weight value of each of the appropriate amount combinations included in the appropriate amount combination set, and selecting one appropriate amount combination set having the smallest difference. A pair obtained as the proper amount combination from the weighing hoppers belonging to the proper amount combinations included in the selected proper amount combination set. Said configured to the discharge path corresponding to the group to perform a second process of determining that the discharge the objects to be weighed, said first process, said first discharge path and the second With respect to the group corresponding to each of all the discharge paths of one of the discharge paths, all the combinations of the weighing hoppers whose combined weight values are within an allowable range with respect to the target weight value are obtained as the first appropriate combination. Third processing for obtaining all semi-suitable combination sets in which the first appropriate combination obtained for each group is combined one by one from each group, the first discharge route and the second discharge route For the group corresponding to each of the other discharge paths of the other, the combination weight value from the weighing hopper excluding each semi-appropriate combination set is allowed for the target weight value. All combinations within the range are obtained, and the combination is set as the second appropriate combination corresponding to each semi-appropriate combination set, and for each of all the semi-appropriate combination sets, the second appropriate combination corresponding to each And a fourth process for obtaining the proper combination set.

  According to this configuration, an appropriate combination set having the minimum difference between the combination weight value of each appropriate combination and the target weight value is selected, and the weighing hoppers belonging to each appropriate combination included in the appropriate combination set are selected. Since the objects to be weighed are discharged to the discharge route corresponding to the target group required as an appropriate amount combination, the accuracy of combination weighing as a whole of the objects to be discharged from the weighing hopper to each discharge route is improved. Can be achieved.

  INDUSTRIAL APPLICABILITY The present invention has the above-described configuration and can improve the combination weighing accuracy as a whole of the objects to be weighed discharged from the weighing hopper to each discharge path in the combination weigher having a plurality of discharge paths. There exists an effect that a combination scale can be provided.

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

(Embodiment)
[First configuration example]
FIG. 1A is a schematic schematic view of a partial cross section of the combination weigher of the first configuration example according to the embodiment of the present invention viewed from the side, and FIG. FIG. 1 is a schematic view of a chute (inner chute and two outer chutes) and a weighing hopper as viewed from above. FIG. 1 (c) is a schematic view of two lower chutes and a discharge hopper as viewed from above. It is.

  In this combination weigher, as shown in FIG. 1 (a), a center base body (body) 5 is supported at the center of the apparatus by, for example, four legs (not shown), and an upper portion is provided with an external supply. A conical dispersion feeder 1 that disperses the object to be weighed supplied from the apparatus radially by vibration is provided. Around the dispersion feeder 1, a plurality of linear feeders 2 are provided for feeding an object to be weighed sent from the dispersion feeder 1 to each supply hopper 3 by vibration. Below each linear feeder 2, a supply hopper 3 and a weighing hopper 4 are provided correspondingly, and the plurality of supply hoppers 3 and the weighing hoppers 4 are arranged in a circle around the center base 5. The dispersion feeder 1, the linear feeder 2, the supply hopper 3, and the weighing hopper 4 are attached to the center base 5, and the drive unit (the vibration device of the dispersion feeder 1 and the linear feeder 2, the supply hopper 3, and the like) A gate opening / closing device of the weighing hopper 4) is accommodated. Each weighing hopper 4 is attached with a weight sensor 41 such as a load cell for measuring the weight of an object to be weighed in the weighing hopper 4. The measurement value by each weight sensor 41 is output to the control unit 20.

  A substantially inverted frustoconical inner chute 6a is disposed below the weighing hoppers 4 arranged in a circle, and the upper opening is concentric around the inner chute 6a and is divided into two outer parts. Chute 6b, 6c is provided. Each weighing hopper 4 has a configuration in which a gate (not shown) is provided so that an object to be weighed can be selectively discharged to the inner chute 6a and the outer chute 6b or 6c below. The groups B and C of the weighing hoppers 4 arranged above the outer chutes 6b and 6c are groups corresponding to the outer chutes 6b and 6c, respectively, and for example, from 9 or 10 weighing hoppers 4 respectively. It is a group. Intermediate hoppers 7b and 7c are disposed at lower discharge ports of the outer chutes 6b and 6c, respectively, and discharge hoppers 8b and 8c are disposed below the intermediate hoppers 7b and 7c. The group A composed of the weighing hoppers 4 of the group B and the group C is a group of the weighing hoppers 4 corresponding to the inner chute 6a. A discharge hopper 8a is disposed at the lower discharge port 6ae of the inner chute 6a. As shown in FIG. 1 (c), lower chutes 9L are arranged below the discharge hoppers 8a and 8b, and lower chutes 9R are arranged corresponding to the discharge hoppers 8a and 8c. Has been. Here, the discharge hopper 8a has a configuration in which a gate (not shown) is provided so that the object to be weighed can be selectively discharged to the two lower chutes 9L and 9R. In addition, the weighing object discharged from the discharge hopper 8b is discharged only to the lower chute 9L, and the weighing object discharged from the discharge hopper 8c is discharged only to the lower chute 9R. The objects to be weighed discharged to the lower chutes 9L and 9R are discharged from the respective discharge ports 9La and 9Ra.

  Below the lower chutes 9L and 9R of this combination weigher, two unillustrated wrapping machines or a twin-type wrapping machine having two input ports for an object to be weighed are arranged, and the discharge port 9La of the lower chute 9L. And the objects to be weighed discharged from the discharge ports 9Ra of the lower chute 9R are respectively input to the input ports of the packaging machine, and are packed while being packed by the packaging machine.

  The control unit 20 controls the operation of the entire combination weigher and performs combination processing described later to determine the combination of the weighing hoppers 4 to which the objects to be weighed are to be discharged.

  The operation of the combination weigher configured as described above will be described.

  The objects to be weighed supplied from the external supply device to the dispersion feeder 1 are supplied from the dispersion feeder 1 to each supply hopper 3 via each linear feeder 2, and the objects to be weighed are input from each supply hopper 3 to each weighing hopper 4. Is done. A combination process or a combination hopper discharge process, which will be described later, is performed, and an object to be weighed is fed from the supply hopper 3 to the empty weighing hopper 4. Similarly, an object to be weighed is supplied from the linear feeder 2 to the empty supply hopper 3.

  When an object to be weighed is put into the weighing hopper 4 and measurement by the weight sensor 41 is performed, the control unit 20 performs combination processing based on the measurement value of the measurement hopper 4 (measurement value by the weight sensor 41). In this combination processing, the objects to be weighed are placed on the inner chute 6a from the group A consisting of the weighing hoppers 4 (all weighing hoppers 4 in the configuration example of FIG. 1) arranged above the inner chute 6a and corresponding to the inner chute 6a. The weighing hopper 4 of the combination to be discharged (this is referred to as the combination hopper 4A) is determined, and the group B consisting of the weighing hopper 4 disposed above the outer chute 6b and corresponding to the outer chute 6b is moved to the outer chute 6b. A weighing hopper 4 of a combination to be discharged (determined as a combination hopper 4B) is determined, and from the group C consisting of the weighing hopper 4 disposed above the outer chute 6c and corresponding to the outer chute 6c, A combination weighing hopper 4 (this is referred to as a combination hopper 4C) for discharging the object to be weighed to the outer chute 6c is determined. The objects to be weighed are discharged simultaneously from the combination hoppers 4A, 4B, 4C determined in this combination process (combination hopper discharge process).

  Next, details of the combination processing in the present embodiment will be described. The combination process includes a first process and a second process. In the first process, each weighing hopper corresponds to each discharge path (each chute 6a, 6b, 6c in the configuration example of FIG. 1). Each weighing hopper belongs to two groups by classifying into groups, and the combined weight value, which is the sum of the weight values of the objects to be weighed supplied to the weighing hopper for each group, is within the allowable range for the target weight value. A combination of weighing hoppers is determined as an appropriate amount combination, and an appropriate amount combination set for each group is combined, and the appropriate amount combination set of different groups to be combined does not include the same weighing hopper. Ask.

  Subsequently, in the second process, for each appropriate amount combination set obtained in the first process, the sum of the difference between the combination weight value of each appropriate amount combination included in the appropriate amount combination set and the target weight value is calculated, Select one appropriate combination set having the smallest difference, and from the weighing hopper belonging to each appropriate combination included in the selected appropriate combination set, the discharge route corresponding to the target group determined as the appropriate combination Decide to discharge the object to be measured.

  By performing this combination processing, an appropriate combination set having the minimum difference between the combination weight value of each appropriate combination and the target weight value is selected, and the measurement belonging to each appropriate combination included in the appropriate combination set. Since the object to be weighed is discharged from the hopper to the discharge path corresponding to the target group required as an appropriate amount combination, each discharge path (each chute 6a, 6b, 6c in the configuration example of FIG. 1) is discharged from the weighing hopper. It is possible to improve the accuracy of combination weighing as a whole of the objects to be weighed.

  In the combination weigher, a target weight value and an allowable range for the target weight value are determined in advance. The allowable range is determined, for example, with a target weight value as a lower limit value and a value larger than the target weight value as an upper limit value. For example, the target weight value is set to 400 g, and the allowable range is set to 400 g whose lower limit value is the target weight value, and its upper limit value is set to 420 g that is larger than the target weight value. In addition, the allowable range may be a value lower than the target weight value as the lower limit value, and the upper limit value may not be determined (in this case, the upper limit value may be considered infinite).

  Furthermore, the combination processing in the above-described embodiment can be roughly divided into two methods, the first method and the second method, and the control unit 20 performs the combination processing by any method.

  First, combination processing by the first method will be described. FIG. 2 is a flowchart showing the combination processing by the first method. Steps S1 and S2 are the first processing, and steps S3 and S4 are the second processing.

  In step S1, combination calculation is performed on each group of weighing hoppers corresponding to each chute that receives an object to be weighed discharged from the weighing hopper so that the combined weight value is within an allowable range for the target weight value. A combination is determined for each group.

  In step S2, an appropriate amount combination set obtained by combining the appropriate amount combinations of each group one by one is obtained.

  In step S3, for each appropriate amount combination set, the sum of the differences between the combination weight value of each appropriate amount combination constituting the appropriate amount combination set and the target weight value is calculated.

  In step S4, one appropriate combination set having the smallest difference is selected, and the weighing hoppers of the appropriate combination of each group constituting the set are determined as hoppers to be discharged to the chute corresponding to the group.

  The case where the combination process by the above first method is applied to the first configuration example will be described. In this case, the control unit 20 has a built-in memory, and information necessary for performing combination processing in advance (information on which weighing hopper each group is configured with, information on a target weight value, allowable range, and the like) Is also stored in the memory, and information generated in combination processing (information on combination weight values, information indicating the appropriate amount combination and the weighing hopper of the appropriate amount combination set, information obtained in steps S3 and S4, etc.) is stored in the memory. Remember.

  In step S1, for each group A, B, C corresponding to each chute 6a, 6b, 6c, the weight value of the object put into each weighing hopper 4 (measured value by weight sensor 41). By performing the combination calculation based on the above, all combinations of the weighing hoppers 4 in which the total weight value (combination weight value) of the objects to be weighed are within the allowable range with respect to the target weight value are obtained, and these combinations are set as appropriate combinations. . Here, a plurality of appropriate amount combinations are usually obtained for each group A, B, and C, and one appropriate amount combination of group A and an appropriate amount combination of groups B and C include one or more identical weighing hoppers 4. Is selected.

  In step S2, an appropriate amount combination set obtained by combining the appropriate amount combinations of the groups A, B, and C one by one is obtained. At this time, the same weighing hopper 4 is not selected for the appropriate combination of group A and the appropriate combination of group B, which constitutes an appropriate appropriate combination set, and is the same as the appropriate combination of group A and the appropriate combination of group C. Appropriate combinations of the groups A, B, and C are combined so that the weighing hopper 4 is not selected.

  In step S3, for each appropriate amount combination set, the difference between the combination weight value of each appropriate amount combination constituting the appropriate amount combination set and the target weight value is obtained, and the sum of these differences is calculated. Here, the difference between the combination weight value and the target weight value is an absolute value obtained by subtracting the target weight value from the combination weight value, and is zero or a positive value.

  In step S4, one appropriate combination set having the smallest difference calculated in step S3 is selected, and the weighing hopper 4 of the appropriate combination of group A constituting the group A should be discharged to the inner chute 6a. The combination hopper 4A is determined, the weighing hopper 4 of an appropriate amount combination of the group B is determined as the combination hopper 4B to discharge the object to be measured to the outer chute 6b, and the weighing hopper 4 of the appropriate amount combination of the group C is set to the outside The combination hopper 4C to be discharged to the chute 6c is determined.

  Based on the determination in step S4, the control unit 20 simultaneously opens the gates of the weighing hoppers 4 (4A, 4B, 4C) so that the objects to be weighed are discharged to the chutes 6a, 6b, 6c. Discharge the sample (combined hopper discharge process).

  In step S1, the combinations of the weighing hoppers 4 in which the combination weight values are within the allowable range with respect to the target weight value are obtained for each of the groups A, B, and C. Of the combinations of the weighing hoppers 4 whose values are within the allowable range with respect to the target weight value, priority is given to a combination having a small difference between each combination weight value and the target weight value (same as above, zero or positive value). N (n is a plurality), for example, 10 may be selected and combined in an appropriate amount. As a result, the number of appropriate combination sets obtained in step S2 is reduced, the processing time in steps S2 to S4 can be shortened, and the time required for the combination process can be shortened. In this case, the difference between the combination weight value and the target weight value is calculated in step S1, but the difference calculated here may be used in the subsequent step S3.

  Next, combination processing by the second method will be described. FIG. 3 is a flowchart showing combination processing by the second method. Steps S11 to S14 are the first processing, and steps S15 and S16 are the second processing.

  In step S11, by performing a combination operation on each group (first each group) of the weighing hopper corresponding to each chute of one of the inside and the outside that receives the object to be discharged from the weighing hopper, An appropriate amount combination whose combination weight value is within an allowable range with respect to the target weight value is obtained for each first group.

  In step S12, a quasi-appropriate amount combination set obtained by combining the appropriate amount combinations of the first groups obtained in step S11 one by one is obtained.

  In step S13, for each group (second group) of the weighing hopper corresponding to the other chute of the inside and the outside, an appropriate amount combination of each second group corresponding to each semi-appropriate amount combination set is obtained. . For each second group, a combination calculation is performed on the weighing hopper excluding each semi-appropriate amount combination set to obtain a combination whose combination weight value is within an allowable range with respect to the target weight value. Is an appropriate amount combination of each second group corresponding to each semi-appropriate amount combination set.

  In step S14, an appropriate amount combination set is obtained by combining each of the semi-appropriate amount combination sets with an appropriate amount combination of the second group corresponding to each set.

  In step S15, for each appropriate amount combination set, the sum of the differences between the combination weight value and the target weight value of each appropriate amount combination constituting the appropriate amount combination set is calculated.

  In step S16, one appropriate combination set having the smallest difference is selected, and the weighing hoppers of the appropriate combination of each group constituting the set are determined as hoppers to be discharged to the chute corresponding to the group.

  A case where the combination processing by the second method described above is applied to the first configuration example will be described. In this case, the control unit 20 has a built-in memory, and information necessary for performing combination processing in advance (information on which weighing hopper each group is configured with, information on a target weight value, allowable range, and the like) Is stored in the memory, and information generated in combination processing or the like (information on combination weight value, information on appropriate amount combination, semi-appropriate amount combination set and weighing hopper of appropriate amount combination set, information obtained in steps S15 and S16) Etc.) in the memory.

  In step S11, each weighing hopper is applied to one of the inner chutes (6a) and the outer chutes (6b, 6c), for example, each of the groups B, C corresponding to the outer chutes 6b, 6c. 4 is performed based on the weight of the object to be weighed (measured value by the weight sensor 41), so that the total weight value (combined weight value) of the object to be weighed is within the allowable range with respect to the target weight value. All combinations of certain weighing hoppers 4 are obtained, and those combinations are determined as appropriate combinations. Here, a plurality of appropriate amount combinations are usually obtained for each of the groups B and C.

  In step S12, a quasi-optimal amount combination set obtained by combining the appropriate amount combinations of the groups B and C one by one is obtained.

  In step S13, the combination calculation is performed based on the weight of the objects to be weighed put into the weighing hopper 4 excluding any one semi-appropriate amount combination set from the group A of the weighing hopper 4 corresponding to the inner chute 6a. Thus, all combinations of the weighing hoppers 4 in which the combination weight value is within the allowable range with respect to the target weight value are obtained, and these combinations are set as an appropriate amount combination of the group A corresponding to the arbitrary one semi-appropriate amount combination set. Similarly, an appropriate amount combination of group A corresponding to each of all the semi-appropriate amount combination sets obtained in step S12 is obtained.

  In step S14, an appropriate amount combination set is obtained by combining each of the semi-appropriate amount combination sets with an appropriate amount combination of group A corresponding to each.

  In step S15, for each appropriate amount combination set, the difference between the combination weight value of each appropriate amount combination constituting the appropriate amount combination set and the target weight value is obtained, and the sum of these differences is calculated. Here, the difference between the combination weight value and the target weight value is an absolute value obtained by subtracting the target weight value from the combination weight value, and is zero or a positive value.

  In step S16, one appropriate combination set having the smallest difference calculated in step S15 is selected, and the weighing hopper 4 of the appropriate combination of group A constituting the group A should be discharged to the inner chute 6a. The combination hopper 4A is determined, the weighing hopper 4 of an appropriate amount combination of the group B is determined as the combination hopper 4B to discharge the object to be measured to the outer chute 6b, and the weighing hopper 4 of the appropriate amount combination of the group C is set to the outside The combination hopper 4C to be discharged to the chute 6c is determined.

  Based on the determination in step S16, the control unit 20 simultaneously opens the gates of the weighing hoppers 4 (4A, 4B, 4C) so that the objects to be weighed are discharged to the chutes 6a, 6b, 6c. Discharge the sample (combined hopper discharge process).

  In step S11, for each of the groups B and C, all combinations of the weighing hoppers 4 in which the combination weight value is within the allowable range with respect to the target weight value are obtained and set as appropriate combinations. Of the combinations of the weighing hoppers 4 that are within the allowable range for the target weight value, the one having a small difference between each combination weight value and the target weight value (same as above, zero or a positive value) is given priority and given n Individual (n is plural), for example, 10 may be selected and combined in an appropriate amount. As a result, the number of semi-appropriate amount combination sets obtained in step S12 is reduced, the processing time in steps S12 to S16 and the like can be shortened, and the time required for the combination process can be shortened. In this case, in step S11, the difference between the combination weight value and the target weight value is calculated. The difference calculated here may be used in the subsequent step S15.

  In step S13, the combination weight value is set to the target value by performing the combination calculation based on the weight of the objects to be weighed put into the weighing hopper 4 excluding any one semi-appropriate amount combination set from the group A. One combination of the weighing hoppers 4 that is within an allowable range for the weight value and has the smallest difference from the target weight value is obtained, and the combination is an appropriate combination of the group A corresponding to any one of the above-mentioned semi-appropriate combination sets. As described above, it is preferable that an appropriate amount combination of group A corresponding to each of all the semi-appropriate amount combination sets is obtained. In this case, there is one appropriate combination of group A corresponding to any one semi-appropriate combination set, and in step S14, the appropriate combination of group A corresponding to each of all of the semi-appropriate combination sets is added. And an appropriate combination set.

  If an appropriate amount combination is obtained for the group A of the weighing hopper 4 corresponding to the inner chute 6a in step S11, in step S12, each of the appropriate amount combinations of group A obtained in step 11 is a semi-appropriate amount combination set. Become. In this case, in step S13, an appropriate combination of groups B and C is obtained corresponding to each of all the semi-appropriate combination sets determined in step S12. In step S14, for each of all the semi-appropriate combination sets, What is necessary is just to obtain | require the appropriate amount combination set which combines the appropriate amount combination of the corresponding groups B and C one by one.

  After the combination process is performed as described above, the discharge process from the weighing hopper 4 is performed.

  FIG. 4 shows the gates of the weighing hopper 4 (combination hoppers 4A, 4B, 4C), the intermediate hoppers 7b, 7c, and the discharge hoppers 8a, 8b, 8c of the combination weigher of the first configuration example of the present embodiment. It is a timing chart which shows an example of operation. This timing chart is shown using the following conditions. Assuming that the gate opening time ta of the weighing hopper 4 is 150 ms, the stability and combination time tb is 700 ms, the weighing cycle T is 850 ms. The stability and combination time tb is the stabilization time of the weight sensor 41 attached to the weighing hopper 4 after the weighing hopper 4 is closed and the weighing object is supplied from the supply hopper 3 to the weighing hopper 4. Is the time required for the weight of the object to be measured to pass and the combination process to be completed. Further, the gate opening time t1 of the intermediate hoppers 7b and 7c and the gate opening time t2 of the discharge hoppers 8a, 8b and 8c are 200 ms, respectively. Further, it is assumed that the time from the opening of the weighing hopper 4 gate to the discharge hopper 8a or the intermediate hoppers 7b and 7c reaching the discharge hopper 8a or the intermediate hoppers 7b and 7c is 400 ms. It is assumed that the time from when the gate is closed until the end of the object to be weighed reaches the discharge hopper 8a or the intermediate hoppers 7b and 7c is 700 ms corresponding to the stability and combination time tb. Further, it is assumed that the time from when the gates of the intermediate hoppers 7b and 7c are opened until the top of the objects to be discharged discharged from the intermediate hoppers 7b and 7c reaches the discharge hoppers 8b and 8c is 200 ms. It is assumed that the time t3 from when the gates of the intermediate hoppers 7b and 7c are closed until all the objects to be weighed discharged from the intermediate hoppers 7b and 7c reach the discharge hoppers 8b and 8c is 200 ms. A broken line extending from the start time of the gate opening operation of each upper hopper (4A, 4B, 4C, 7b, 7c) to a line indicating the operation timing of the lower hopper (7b, 7c, 8a, 8b, 8c). Indicates the time when the top of the object to be weighed discharged from the upper hopper reaches the lower hopper, and from the end time of the opening operation of each upper hopper to the line indicating the operation timing of the lower hopper The extending broken line indicates the time when the last of the objects to be weighed discharged from the upper hopper reaches the lower hopper. For example, the objects to be weighed discharged from the combination hoppers (4A, 4B, 4C) during the time 0.0 to 0.15 (sec) start at the lower hoppers (8a, 7b, 7c). A broken line indicates that the arrival time is 0.4 (sec) and the last time is 0.85 (sec).

  As shown in FIG. 4, the objects to be weighed discharged simultaneously from the combination hoppers 4A, 4B, and 4C are collected and temporarily held in the discharge hopper 8a and intermediate hoppers 7b and 7c, respectively. The objects to be weighed collected in the intermediate hoppers 7b and 7c are simultaneously transferred to the discharge hoppers 8b and 8c and temporarily held. The objects to be weighed transferred to the respective discharge hoppers 8a, 8b, 8c in this way are discharged from the respective discharge hoppers 8a, 8b, 8c at different timings, and the two lower chutes 9L, 9R. Alternately discharged. The objects to be weighed discharged from the discharge hopper when the gate is opened at times TR1 to TR6 are discharged to the lower chute 9R, and the objects to be weighed are opened from the discharge hopper at times TL1 to TL6. Is discharged to the lower chute 9L. In the discharge hopper 8a, a discharge operation is performed so that the objects to be weighed are discharged alternately to the lower chute 9R and the lower chute 9L, and this discharge operation cycle is equal to the weighing cycle T. For example, when the gate of the discharge hopper 8a is opened at time TR2 and the object to be weighed is discharged to the lower chute 9R, the gate of the discharge hopper 8b is opened at time TL3 and the object to be weighed is moved to the lower chute 9L. Further, at time TR3, the gate of the discharge hopper 8c is opened, and the object to be weighed is discharged to the lower chute 9R. Subsequently, when the gate of the discharge hopper 8a is opened at time TL4 and the object to be weighed is discharged to the lower chute 9L, the gate of the discharge hopper 8c is opened at time TR4 and is measured to the lower chute 9R. The material is discharged, and further, at time TL5, the gate of the discharge hopper 8b is opened, and the object to be weighed is discharged to the lower chute 9L. The timing at which the objects to be weighed are alternately discharged to the lower chute 9R and the lower chute 9L is shifted by a time of T / 3. By operating as described above, the object to be weighed is discharged to the two lower chutes 9L and 9R three times during the two weighing cycles (2 × T). Accordingly, a high-speed discharge operation is possible such that the objects to be weighed are discharged three times from the discharge ports 9La and 9Ra in two measurement cycles.

[Second configuration example]
FIG. 5A is a schematic schematic view of a partial cross section of the combination weigher of the second configuration example according to the embodiment of the present invention as viewed from the side, and FIG. It is the schematic diagram which looked at the chute (the inner chute and the two outer chutes) and the weighing hopper from above.

  In the combination weigher of this configuration example, the discharge hoppers 8a, 8b, 8c and the lower chutes 9L, 9R in the first configuration example are not provided, and the object to be weighed is temporarily held in the lower discharge port 6ae of the inner chute 6a. A collecting hopper 7a for discharging is disposed. Other configurations are the same as those of the first configuration example, and the description thereof is omitted. Here, the hoppers 7b and 7c that are disposed in the lower discharge ports 6be and 6ce of the outer chutes 6b and 6c and are called the intermediate hoppers in the first configuration example are called collective hoppers.

  Below this combination weigher, three packaging machines (not shown) or a packaging machine having three input ports for objects to be weighed are arranged, and the weighing objects discharged from the respective collecting hoppers 7a, 7b, 7c. Each item is put into the input port of the packaging machine and packed while being packed in the bag by the packaging machine.

  The control unit 20 controls the operation of the entire combination weigher, performs the combination processing described above, and combines the weighing hoppers 4 (combination hoppers 4A, 4B, 4C) to discharge the objects to be weighed to the chutes 6a, 6b, 6c. ). Then, the gates of the combination hoppers 4A, 4B, and 4C determined by the combination process are simultaneously opened to discharge the objects to be weighed. The objects to be weighed are collected in the collecting hoppers 7a, 7b, 7c and temporarily held. Thereafter, the gates of the collecting hoppers 7a, 7b and 7c are simultaneously opened, and the respective objects to be weighed are discharged to the respective inlets of the packaging machine which is an external device.

  In the present configuration example, the objects to be weighed discharged from the weighing hopper 4 to the respective chutes 6a, 6b, 6c are loaded into the input ports of different packaging machines and packaged.

[Third configuration example]
FIG. 6A is a schematic schematic view of a partial cross section of the combination weigher of the third configuration example according to the embodiment of the present invention viewed from the side, and FIG. It is the schematic diagram which looked at the chute (two inner chutes and two outer chutes) and the weighing hopper from above.

  In this configuration example, the inner chute is divided into two inner chutes 6d and 6e in the second configuration example shown in FIG. 5, and the lower discharge ports 6de and 6ee of the inner chutes 6d and 6e are covered. Collective hoppers 7d and 7e for temporarily holding and discharging the weighing objects are provided. In FIG. 6A, the inner chute 6e and the collecting hopper 7e are hidden behind the inner chute 6d and the collecting hopper 7d. The configuration other than the above is the same as the second configuration example, and the description thereof is omitted.

  Below this combination weigher, four packaging machines (not shown) or a packaging machine having four input ports for objects to be weighed are arranged and discharged from each of the collecting hoppers 7b, 7c, 7d and 7e. The objects to be weighed are respectively input into the input ports of the packaging machine, and are packed while being packed in the packaging machine.

  The control unit 20 controls the operation of the entire combination weigher and performs the above-described combination processing, and the combination weighing hoppers 4 (combination hoppers 4B, 4C) to discharge the objects to be weighed to the chutes 6b, 6c, 6d, 6e. 4D, 4E). Then, the gates of the combination hoppers 4B, 4C, 4D, and 4E determined by the combination process are simultaneously opened to discharge the objects to be weighed. The objects to be weighed are collected in the collecting hoppers 7b, 7c, 7d and 7e and temporarily held. Thereafter, the gates of the respective collecting hoppers 7b, 7c, 7d, and 7e are simultaneously opened, and the respective objects to be weighed are discharged to the respective inlets of the packaging machine that is an external device.

  In this configuration example, the objects to be weighed discharged from the weighing hopper 4 to the chutes 6b, 6c, 6d, and 6e are respectively fed into the inlets of different packaging machines and packaged.

  In this configuration example, the division positions of the inner chutes 6d and 6e are different from the division positions of the outer chutes 6b and 6c, but the groups D and E corresponding to the inner chutes 6d and 6e are divided at the same position. Alternatively, the same group of weighing hoppers 4 as the groups B and C corresponding to the outer chutes 6b and 6c may be used. In this case, each of the collecting hoppers 7b, 7c, 7d, and 7e can be arranged almost linearly.

[Fourth configuration example]
FIG. 7A is a schematic schematic view of a partial cross section of the combination weigher of the fourth configuration example according to the embodiment of the present invention viewed from the side, and FIG. It is the schematic diagram which looked at the chute (inner chute and outer chute) and the weighing hopper from above.

  In this configuration example, neither the inner chute nor the outer chute is divided in the second configuration example shown in FIG. 5, and the object to be weighed is temporarily held in the lower discharge port 6fe of the inner chute 6f. A collecting hopper 7f is provided for discharging the collected objects, and a collecting hopper 7g for temporarily holding and discharging the objects to be weighed is provided at the lower discharge port 6ge of the outer chute 6g. The configuration other than the above is the same as that of the second configuration example, and the description thereof is omitted (in this case, the discharge hoppers 8f and 8g and the lower chute 9 indicated by the chain line in FIG. 7A are not provided). Configuration).

  Below the combination weigher, two packaging machines (not shown) or a packaging machine having two input ports for the objects to be weighed are arranged, and the objects to be weighed discharged from the respective collection hoppers 7f and 7g are , Each is put into the input port of the packaging machine, and packed while being packed in a bag by the packaging machine.

  The control unit 20 controls the operation of the entire combination weigher and performs the above-described combination processing, so that the combination weighing hoppers 4 (referred to as combination hoppers 4F and 4G) for discharging the objects to be weighed to the chutes 6f and 6g. decide. Then, the gates of the combination hoppers 4F and 4G determined in this combination process are simultaneously opened to discharge the objects to be weighed. The objects to be weighed are collected in the collecting hoppers 7f and 7g and temporarily held. Thereafter, the gates of the collecting hoppers 7f and 7g are simultaneously opened, and the respective objects to be weighed are discharged to the respective inlets of the packaging machine which is an external device.

  In the present configuration example, the objects to be weighed discharged from the weighing hopper 4 to the respective chutes 6f and 6g are put into the inlets of different packaging machines and packaged.

  In this configuration example, as shown by the chain line in FIG. 7A, the objects to be weighed discharged from the respective collection hoppers 7f and 7g are temporarily held and discharged below the respective collection hoppers 7f and 7g. Discharge hoppers 8f and 8g are disposed, and one lower chute 9 is disposed for feeding the objects to be weighed discharged from each of the discharge hoppers 8f and 8g into one input port of the packaging machine. It can also be configured. In this case, a single packaging machine having one input port (not shown) is arranged below the combination weigher, and alternately discharges the objects to be weighed from the discharge hoppers 8f and 8g twice in one weighing cycle. The object to be weighed is discharged to the lower chute 9. Therefore, a high-speed discharge operation is possible such that the object to be weighed is discharged twice from the discharge port 9a of the lower chute 9 in one weighing cycle.

  Similarly, in the configuration example shown in FIG. 6, the objects to be weighed discharged from the respective collection hoppers 7b, 7c, 7d, 7e are temporarily held and discharged below the respective collection hoppers 7b, 7c, 7d, 7e. And a lower chute for feeding the objects to be weighed discharged from each of the four discharge hoppers into one input port of the packaging machine, and in one weighing cycle It is also possible to configure so that the object to be weighed is discharged from the outlet of the lower chute to the packaging machine four times. Further, in this configuration, instead of one lower chute, two lower chutes 9L and 9R are arranged as shown in FIG. 1, and the objects to be weighed sequentially from the four discharge hoppers are two lower chutes. You may comprise so that it may distribute to 9L and 9R alternately. In this case, the objects to be weighed are discharged to the two lower chutes 9L and 9R twice in one weighing cycle, and the objects to be weighed are discharged from the discharge ports 9La and 9Ra to the two input ports of the packaging machine.

  The combination process described in the present embodiment is provided with one or more inner chutes and one or more outer chutes for the weighing hoppers 4 arranged as shown in the above configuration example, The present invention can be applied to a configuration in which the weighing hopper 4 can be selectively discharged to the inner chute and the outer chute located below. For example, in the configuration examples shown in FIGS. 1, 5, and 6, the outer chute may be divided into three or more, or the inner chute may be divided into three or more. Also good. In the configuration example shown in FIG. 7, the inner chute may be divided into two or more.

  In each configuration example of the present embodiment, the weighing hoppers 4 are arranged in a circle, but the configuration is not limited to this configuration. For example, the weighing hoppers 4 are arranged not only in a circular shape but also in an annular shape including polygonal shapes such as an ellipse, a rectangle, and a rectangle, and outer and inner chutes are arranged corresponding to the arranged weighing hoppers 4. It only has to be done. Further, in the configuration in which the weighing hoppers 4 are arranged in the above rectangular shape, the weighing hoppers 4 are arranged in two lines in a straight line without the weighing hoppers 4 being arranged on the two short sides of the rectangle. Other configurations may be used. In this case, for example, one inner chute having a rectangular upper opening shape is disposed between two outer chutes having a rectangular upper opening shape for receiving an object to be weighed discharged from the weighing hopper 4. The weighing hopper 4 is arranged on the boundary between each outer chute and the inner chute. In this configuration, any one of the outer chutes and the inner chutes may be divided into a plurality.

  Further, in each configuration example, the control unit 20 does not necessarily need to be configured by a single control device, and a plurality of control devices are arranged in a distributed manner so that they cooperate to control the operation of the combination weigher. It may be configured.

  The combination weigher according to the present invention is useful for a combination weigher provided with a plurality of discharge paths for objects to be weighed discharged from each weighing hopper.

(A) is the schematic schematic diagram of the partial cross section which looked at the combination weigher of the 1st structural example of embodiment of this invention from the side, (b) is the collective chute (inner chute) of the combination weigher And two outer chutes) and a weighing hopper when viewed from above. FIG. 10C is a schematic diagram when two lower chutes and a discharge hopper of the combination weigher are viewed from above. It is a flowchart which shows the combination process by the 1st method in the combination scale of embodiment of this invention. It is a flowchart which shows the combination process by the 2nd method in the combination scale of embodiment of this invention. It is a timing chart which shows an example of operation | movement of the combination scale of the 1st structural example of embodiment of this invention. (A) is the schematic schematic diagram of the partial cross section which looked at the combination weigher of the 2nd structural example of embodiment of this invention from the side, (b) is the collective chute (inner chute) of the combination weigher And two outer chutes) and a weighing hopper when viewed from above. (A) is a schematic schematic diagram of a partial cross section of the combination weigher of the third configuration example of the embodiment of the present invention as viewed from the side, and (b) is an assembly chute (two pieces of the combination weigher) It is the schematic diagram which looked at the inner side chute and the two outer side chutes) and the weighing hopper from above. (A) is the schematic schematic diagram of the partial cross section which looked at the combination weigher of the 4th structural example of embodiment of this invention from the side, (b) is the collective chute (inner chute) of the combination weigher And an outer chute) and a weighing hopper as viewed from above. (A) is the schematic schematic diagram of the partial cross section which looked at the combination weigher of the conventional example from the side, (b) is the collective chute (inner chute and two outer chutes) and the weighing hopper of the same combination weigher. It is the schematic model seen from the upper part, (c) is the schematic model figure which looked at two lower chutes, the intermediate hopper, and the discharge hopper of the combination weigher from the upper part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Dispersing feeder 2 Linear feeder 3 Supply hopper 4 Weighing hopper 5 Center base | substrate 6a, 6d, 6e, 6f Inner chute 6b, 6c, 6g Outer chute 7a, 7b, 7c, 7d, 7e, 7f, 7g Intermediate hopper (collection hopper)
8a, 8b, 8c, 8f, 8g Discharge hoppers 9L, 9R, 9 Lower chute 20 Control unit

Claims (1)

A group of weighing hoppers for weighing the objects to be weighed respectively and selectively discharging in the first and second directions;
Two or more first discharge paths that are respectively provided corresponding to the plurality of weighing hoppers and to which the objects to be weighed discharged from the corresponding weighing hoppers in the first direction are transferred;
One or more second discharge paths that are respectively provided corresponding to the plurality of weighing hoppers and to which the objects to be weighed discharged from the corresponding weighing hoppers in the second direction are transferred;
Control means,
The control means includes
The weighing hoppers belong to the two groups by classifying the weighing hoppers into groups corresponding to the discharge paths, and the weighing objects supplied to the weighing hoppers for the groups. A combination of weighing hoppers whose combined weight value, which is the sum of the weight values of the objects, is within an allowable range with respect to the target weight value, is determined as an appropriate amount combination, and the appropriate amount combinations of the respective groups are combined one by one, And a first process for obtaining an appropriate amount combination set that does not include the same weighing hopper in the appropriate amount combinations of the different groups to be combined;
For each appropriate amount combination set obtained in the first process, a sum of differences between a combination weight value and a target weight value of each appropriate amount combination included in the appropriate amount combination set is calculated, and the sum of the differences is calculated. Select one of the appropriate quantity combination sets that is the minimum, and correspond to the group of objects that are determined as the appropriate quantity combination from the weighing hoppers that belong to each of the appropriate quantity combinations included in the selected appropriate quantity combination set And a second process for determining that the object to be weighed is discharged into the discharge path ,
The first process includes
A combination of the weighing hoppers whose combination weight value is within an allowable range with respect to a target weight value for a group corresponding to each of all the discharge paths of one of the first discharge path and the second discharge path. A third process for determining all the semi-optimal combination sets obtained by combining all the first appropriate combination obtained from each group and obtaining the first appropriate combination obtained from each group;
For a group corresponding to each of the other discharge paths of the other one of the first discharge path and the second discharge path, a combination weight value is set as a target from among the weighing hoppers excluding each semi-appropriate combination set. All combinations that are within an allowable range for the weight value are obtained, and the combinations are set as the second appropriate amount combinations corresponding to the respective semi-appropriate amount combination sets. A combination weigher comprising: a fourth process for obtaining the appropriate amount combination set obtained by combining two appropriate amount combinations one by one.

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