JPH0332726B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention provides a combination weigher, in which a plurality of supply troughs are provided around a dispersion plate, each supply trough is provided with a weighing hopper, the dispersion plate is provided with a conveyor for distributing the object to be weighed on the plate, and the dispersion plate is provided on the supply trough. A conveyor is installed to transport the object to be weighed above to the weighing hopper.
The present invention relates to an improvement in a device for adjusting conveyance conditions for objects to be weighed in a combination weigher in which a control device selects a set of a plurality of weighing hoppers that reach a set weight or a weight close to the set weight. In conventional combination scales, a volume for adjusting the transport force is connected to the transport machine, and the operator has to rely on intuition to adjust the volume, then check the hopper selection result on the control device to start the work and repeat the process of setting conditions several times. I was doing it. Therefore, the adjustment work is time-consuming and is often adjusted to inappropriate conditions.In such cases, it is difficult to find a combination that will reach the set weight, resulting in poor work efficiency. The present invention has been made in view of the above-mentioned conventional circumstances, and its purpose is to facilitate and speed up the adjustment work by automatically adjusting the conveyance state of objects to be weighed in a combination scale before the start of the combination work. Another object of the present invention is to provide a combination scale that always maintains optimal conveyance conditions and has excellent work efficiency. The conveyance condition adjustment device for the object to be weighed in the combination weigher of the present invention includes, in the combination weigher as described above, an input section for inputting the set weight and the conveyance conditions of the supply trough, and a plurality of data of the conveyance conditions stored in advance. The storage unit calculates the weighing average value of the objects to be weighed transported into the weighing hopper for each transport condition, and determines whether the average value is within the tolerance of the set target value of the weighing hopper, and determines the tolerance. If the difference is within the tolerance, a check section determines whether or not it is repeated a predetermined number of times; when the check result of the check section satisfies the average value within the tolerance for a predetermined number of times, the conveyance conditions are changed to the conditions of the supply trough. The present invention is characterized in that it is equipped with a conveyance condition adjustment section that selects and determines the conveyance conditions, and that the conveyance conditions are adjusted before the start of the combination work. A combination scale using an electromagnetic vibrating feeder as a conveyor according to an embodiment of the present invention will be explained with reference to FIGS. An electromagnetic vibration type feeder 3 is provided below the dispersion plate 1 so that the objects to be weighed on the dispersion plate 1 are conveyed in different directions. Supply troughs 2 are arranged in parallel on the outer side of the distribution plate 1, each supply trough 2 is provided with an electromagnetic vibration type feeder 4, and a pool hopper 6 is provided at the discharge end of each supply trough. A weighing hopper 5 having a weighing mechanism is disposed below each pool popper 6. Describing the order of conveyance of the objects to be weighed in the above-mentioned combination weigher, first, the objects to be weighed are fed onto the dispersion plate 1;
The particles are conveyed on the distribution plate 1 by the feeder 3 in the direction of the arrow in FIG. 3 and are dispersed. The feeder 3 is continuously driven. When the pool hopper 6 becomes empty, the feeder 4 of the supply trough 2 is driven for a predetermined period of time, thereby conveying the object to be weighed from the distribution plate 1 to the pool hopper 6. That is, the feeder 4 is driven intermittently. The pool hopper 6 stores the objects to be weighed, and when the weighing hopper 5 is empty, the bottom cover is opened and the objects to be weighed are dropped. The weighing hopper 5 opens only the combined weight selected by the control device,
A combination of predetermined weights is created. Next, to explain the feeders 3 and 4 with reference to FIG. 4, they are 20 leaf springs in the figure, and are connected to the machine frame 22 and the trough 2 (or dispersion plate) via the mounting plate 21 in parallel so that the front side in the conveyance direction is lower. Install. A vibrator magnet 23 is provided on one side of the mounting plate 21, and a movable element 24 is provided on the other side. The movable element 24 is reciprocated up and down by driving the vibrator magnet 23 with a driver to be described later. In such feeders 3 and 4, the conveyance amount can be changed by changing the amplitude, vibration time, vibration frequency, etc., and the conveyance conditions described below are one or more of these. The conveyance condition adjusting device of the present invention will be explained with reference to the principle block diagram of FIG.
0, the condition adjustment section 12 of the dispersion feeder and the condition adjustment section 14 of the supply feeder are connected to a central processing unit CPU. The input section 8 is equipped with an input operation section consisting of a numeric keypad for input, a display section for setting weight, etc., an indicator light for displaying the hopper to be combined, etc., and is connected to the central processing unit.
The set weight is input to the CPU, the conveyance conditions to each feeder, etc. The hopper selection section 9 determines whether the combined weight of the weighing hoppers 5 calculated by the central processing unit CPU is the set weight or a weight close to it, and opens the discharge gate 7 of the weighing hoppers 5 forming the combination. Each of the discharge gates 7 is provided with a gate driving circuit, that is, a driver 16, and the driver 16 is connected to the hopper selection section. The check section 10 is designed to check the weight of the object to be weighed stored in the weighing hopper 5 by setting a check standard as described below based on the set weight. It is something that can be conveyed to people. The conveyance condition adjustment units 12 and 14 are drive circuits for the dispersion feeder 3 and the supply feeder 4, that is, the driver 1, respectively.
1 and 13, respectively, and the check part 1
Based on the command 0, if the weight is light, the conveyance conditions are increased, and if the weight is heavy, the conveyance conditions are adjusted to be lowered. The adjustment amount of the conveyance conditions at this time, for example, the conveyance time of the feeder 4, is determined by storing the adjusted conveyance time per unit weight in the adjustment section 14 in advance.
The transportation time should be adjusted to correspond to the excess or deficiency of weight. When adjusting the amplitude, the weight relative to the set weight is calculated as a percentage, and the amplitude is increased or decreased in proportion to that percentage. The weighing hopper 5 is connected to the central processing unit CPU via the A/D converter 17, and each weighing hopper 5
The weights of the objects to be weighed are calculated, and the respective weights are combined to determine the combination in the hopper selection section 9. Further, a drive circuit for the pool hopper 6, that is, a driver 18, is connected to the central processing unit CPU to supply the object to be weighed into the empty weighing hopper 5, and also to drive the supply feeder 4 of the empty weighing hopper 6 to remove the weighing material from the pool hopper 6. Store the object to be weighed in. Next, the check criteria for the transport conditions of objects to be weighed will be described. For example, when combining four hoppers with a set weight of 200g, the conveyance conditions are f, g,
When h and i were taken, the following table was obtained (unit: g).

[Table] To obtain 200g with four hoppers, the set target value should be 50g/hopper, and the standards are as follows: (a) Set the average value and allowable value of scales 1 to 10 in advance, and set the condition f. , g, h, i, are within tolerance. (b) In addition to the above standard (a), a standard deviation value to be used as a standard is determined in advance, and variations in conditions f, g, h, and i are also taken into account and used as a standard. That is, even if the average value is within the tolerance, if the standard deviation value is large and the individual data vary, the conveyance conditions are readjusted (especially useful in the case of a supply trough). The average value of each of the above conditions is f=47.4 g=49.4 h=48.8 i=53, and if the average value is 50±1 in criterion (a), condition (g) is selected. Since it cannot be determined that condition (g) is necessarily appropriate with a single check, set a predetermined number of measurements (for example, three times) under condition (g) and check whether condition (g) satisfies the standard for the predetermined number of times. I'll do what I do. (c) Another criterion may be to determine whether more or less of the combined weights under each condition f, g, h, and i fall within the set weight tolerance. Next, the automatic adjustment of conveyance conditions in the embodiment of the present invention will be explained with reference to the flowchart of FIG. 5. First, the process starts with the power turned on (30), and the set weight and the number of hoppers to be combined are set (31). Next, after starting the adjustment operation (32), the conveyance conditions (A: for example, the amplitude, frequency, and vibration time of the feeder) are set automatically or manually from the input section (33),
The counter in the central processing unit CPU is set to 0 (34). After the supply feeder 4 is driven to store the objects to be weighed in the pool hopper 6, the objects to be weighed are stored in the weighing hopper 5 (35) and weighed (36). Based on the above standard (b), it is determined whether the weight of the object to be measured satisfies the standard (37), and if the standard is satisfied, the counter is counted by one (38), and the number of repetitions of the condition that satisfies the standard is a predetermined number. (39). If the predetermined number is reached, this condition is memorized (40) and a combination operation is performed (41). If the predetermined number is not reached, the same transport conditions are set (44), the hopper 5 is fully opened and discharged (45), and steps (35), (36), (37), (38), and (39) are repeated. In step (37), if the object to be weighed is negative, the conditions are increased by a predetermined amount (42), if it is positive, the conditions are lowered (43), and the object to be weighed is discharged (45).
Repeat steps (33) (34) (34) (35) (36) (37). The conveyance condition (A) in the above flowchart is set for either the feeder 3 of the distribution plate or the feeder 4 of the supply trough. When adjusting the conveyance conditions of both feeders 3 and 4, the flowchart shown above is repeated for the distribution plate and the supply trough (see FIG. 6). In the above embodiment, the adjustment work was performed at the beginning of the combination work, but it is optional that automatic adjustment may be performed when the combination cannot be obtained in the middle of the work. According to the present invention, as described above, since the conveyance conditions of the supply trough are appropriately adjusted prior to the combination weighing operation, a combination with high measurement accuracy can be quickly obtained from the beginning of the combination weighing. Also, calculate the average value of the weight conveyed into the weighing hopper for each of the plurality of conveyance conditions input in advance, and determine whether the average value is within the tolerance of the set target value of the weighing hopper, Furthermore, if it is within the tolerance, it is confirmed that it is returned a predetermined number of times, and the conveyance conditions of the supply trough are determined, so that the weighing value of each weighing hopper is set to an appropriate conveying state close to the set target value, Moreover, instead of adjusting the conveyance conditions each time to equalize the weight values of each weighing hopper as in the cited example, the conveyance conditions are adjusted before the start of the combination work, and the supply trough is driven under optimal conditions to achieve the set goals. Since the values vary within a small range, each weighing hopper has more chances to be selected for a combination, which can eliminate the problem of only a specific weighing hopper being selected consecutively, and increase the number of combinations. Processing speed is improved. By doing so, we will reach our intended purpose.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing the principle of the conveyance condition adjusting device of the present invention, Fig. 2 is a front view of the combination weigher, Fig. 3 is a plan view thereof, Fig. 4 is a detailed view of the feeder, Figs. 5 and 6. FIG. 2 is a flowchart showing the order of adjustment of conveyance conditions. In the figure, 1...distribution plate, 2...supply trough, 3,
4... Feeder, 5... Weighing hopper, 8... Input section, 9... Hopper selection section, 10... Conveyance condition check section, 12, 14... Conveyance condition adjustment section.

Claims (1)

[Claims] 1. A plurality of supply troughs are provided around the distribution plate, each supply trough is provided with a weighing hopper, and the distribution plate is provided with a conveyor for dispersing the object to be weighed on the plate, and the distribution plate is provided with the distribution plate in the supply trough. In a combination weigher, a combination weigher is provided with a conveyor for conveying the above-mentioned object to be weighed to a weighing hopper, and a control device selects a set of a plurality of weighing hoppers that reach a set weight or a weight close to the set weight. an input unit for inputting a plurality of data of the transport conditions; a storage unit for pre-storing a plurality of data of the transport conditions; and a storage unit that calculates a weighing average value of the objects to be weighed transported into the weighing hopper for each transport condition, and calculating the average value of the weighing object in the weighing hopper. A check section that determines whether or not the set target value is within the tolerance, and if it is within the tolerance, determines whether or not it is repeated a predetermined number of times, and the check result of the check section is the average value within the tolerance. a conveyance condition adjustment section that selects and determines the conveyance condition as the condition of the supply trough when the condition is satisfied a predetermined number of times, and adjusts the conveyance condition before starting the combination work.