JP6446301B2 - Weight sorter - Google Patents

Description

  The present invention relates to a weight sorting apparatus that measures an object to be weighed, such as meat, fish, processed food, and medicine, and sorts the object to be weighed according to the measurement result.

  2. Description of the Related Art Conventionally, in a production line for foods and the like, articles to be manufactured are sequentially carried in from the front stage, weighed while transporting the carried articles, and are carried out from the production line by a carry-out or sorting mechanism to the rear stage. A weight sorter to eliminate is used.

  Since such a weight sorting apparatus is installed and installed in a production line of a manufacturing factory, a measurement error occurs due to the influence of disturbance such as vibration, atmospheric pressure change, temperature change, and humidity change of the manufacturing factory.

  On the other hand, what was described in patent document 1 is known as a conventional weight sorter. The device described in the patent document is a weight selection device that measures an object to be weighed stationary on a load sensor and selects an object to be measured based on the measurement result. Physical quantity data such as atmospheric pressure is measured, correction data corresponding to the physical quantity data is calculated, and the measurement value of the object to be measured is corrected by the correction data.

Japanese Patent No. 4087976

  However, when the measurement value is corrected using the correction data, there is a correction limit range in which the measurement value can be calculated with high accuracy.Therefore, a large disturbance exceeding the correction limit range, such as large vibrations, sudden fluctuations in atmospheric pressure, temperature and humidity, etc. If it occurs, the measured value cannot be corrected with high accuracy.

  For this reason, the conventional weight sorting apparatus described in Patent Document 1 cannot correctly calculate the measured value when subjected to a large disturbance, so the measured value has fallen from the reference range to the reference range due to the disturbance. There is a possibility that the product to be weighed is erroneously determined to be a non-defective product, and the defective product is selected as a non-defective product.

  Therefore, the present invention has been made to solve the above-described conventional problems, and an object of the present invention is to provide a weight sorting device capable of preventing a defective product from being erroneously sorted as a non-defective product. .

  The weight selection device according to the present invention includes a weighing unit that outputs a weighing signal according to the load of the objects to be weighed sequentially, a weighing unit that receives the weighing signal and calculates a measurement value of the weighing object, A sorting unit that determines a direction of sorting the object to be weighed based on the measured value and outputs a sorting signal; and a physical quantity that can act on the weighing unit and change the weighing signal. An environmental measurement unit that measures the environmental data as an environmental data, and an influence calculation unit that receives the environmental data measured by the environmental measurement unit and calculates the degree of influence on the measured value in accordance with a change in the environmental data in a predetermined period And an impact determination unit that determines whether there is an influence on the determination of the selection unit based on whether or not the degree of influence is within a predetermined allowable range, and the selection unit is determined by the influence determination unit The result is influential To output a sorting signal for sorting in one sorting direction, and sorting in another sorting direction according to the judgment by the measurement value from the weighing unit when the determination result of the influence determining unit is unaffected. The selection signal is output.

  With this configuration, the sorting unit outputs a sorting signal for sorting in one sorting direction when the determination result of the influence determining unit has an influence, and according to the measurement value when the determination result of the influence determining unit has no influence. Since a sorting signal for sorting in another sorting direction is output, it is possible to prevent a defective product from being erroneously sorted as a non-defective product due to environmental fluctuations that affect weighing.

  In the weight selection apparatus according to the present invention, the influence degree calculation unit calculates, as the influence degree, a converted value obtained by converting the fluctuation amount of the environmental data in the predetermined period as a change amount of the measured value in grams. It is characterized by that.

  With this configuration, the influence value calculation unit calculates the conversion value obtained by converting the fluctuation amount of the environmental data in the predetermined period as the increase / decrease amount of the measurement value as the influence value, so that the user can determine the increase / decrease amount of the measurement value. Since the degree of influence can be grasped as a converted value converted into grams, the allowable range used by the influence determination unit can be appropriately set. For this reason, it can prevent that the determination of an influence determination part becomes unnecessarily severe.

  Moreover, in the weight selection apparatus according to the present invention, the selection unit determines based on the selection direction determined based on an influence subtraction value obtained by subtracting the converted value within the allowable range from the measurement value and the measurement value. If the sorting direction does not match, the sorting direction is determined as a defective product.

  With this configuration, when the selection direction determined based on the influence subtraction value and the selection direction determined based on the measurement value do not match, the determination of the selection direction may change even if the influence is small. For this reason, it is possible to more reliably prevent a defective product from being erroneously selected as a non-defective product due to environmental fluctuations by determining the sorting direction by regarding the object to be weighed as a defective product.

  In the weight sorting apparatus according to the present invention, the weighing unit includes a transport unit that transports the object to be weighed, and the influence calculation unit is configured to transport the object to be weighed measured by the environment measuring unit. A correction unit that calculates the converted value based on a fluctuation amount of the environmental data in a period on the unit, corrects the measured value using the converted value within the allowable range, and outputs the corrected value to the selection unit; It is characterized by that.

  With this configuration, when the converted value calculated based on the fluctuation amount of the environmental data has a strong correlation with the error of the measured value, the converted value can be used to correct the measured value. As a result, the accuracy of the measurement value can be improved.

  Moreover, in the weight selection apparatus according to the present invention, the influence degree calculation unit calculates an influence level represented by a stepwise level value as the influence degree, and the influence determination unit includes a predetermined one of the influence levels. A level value is set as the allowable range.

  With this configuration, the user can easily store stepwise influence level values (level 1 to level 4 etc.) using an index such as the measured environmental data variation rate and select the level value. An allowable range can be set.

  The weight selection apparatus according to the present invention may further include a storage unit that stores the degree of influence at a predetermined timing, and a display unit that displays the degree of influence stored in the storage unit together with the allowable range. Features.

  With this configuration, the user can confirm the influence level and the allowable range on the display unit, identify the cause of the influence level exceeding the allowable range, and improve the manufacturing equipment in which the weight sorter is installed. it can.

  The present invention can provide a weight sorting device that can prevent a defective product from being erroneously sorted as a non-defective product.

It is a perspective view which shows the outline | summary of the weight selection apparatus which concerns on one embodiment of this invention. It is a block diagram which shows the internal structure of the weight selection apparatus which concerns on one embodiment of this invention. It is a figure which shows the structure of the signal processing part of the weight selection apparatus which concerns on one embodiment of this invention. (A) is a weighing signal mixed with vibration components before being corrected by the signal processing unit, (b) is a correction signal generated by the correction signal generating unit, and (c) is a vibration effect removed. It is a weighing signal. (A) is a side view which shows the conveyance part of the weight selection apparatus which concerns on one embodiment of this invention, (b) is a figure which shows the time change of a weighing signal. It is a figure which shows the structure of the environment measurement part of the weight selection apparatus which concerns on one embodiment of this invention. (A), (b), (c) is a figure which respectively shows the time change of the weighing signal of the weight selection device which concerns on one embodiment of this invention, an influence degree, and influence determination. It is a figure which shows the structure of the selection part of the weight selection apparatus which concerns on one embodiment of this invention. It is a figure which shows the change of a measured value when the selection part of the weight selection apparatus which concerns on one embodiment of this invention removes the bias as an influence degree. It is a figure which shows the example of a display of the display part of the weight selection apparatus which concerns on one embodiment of this invention.

  Hereinafter, embodiments of a weight sorting apparatus according to the present invention will be described with reference to the drawings. 1 to 10 show an embodiment of a weight sorting apparatus according to the present invention.

  First, an outline of the weight sorting apparatus 1 will be described. As shown in FIG. 1, the weight sorting device 1 includes an apparatus main body 2, a transport unit 3, and a carry-in sensor 4. A distribution unit 5 is connected to the subsequent stage of the weight selection device 1.

  The weight sorting apparatus 1 is installed on the downstream side of the belt conveyor 14 constituting a part of the production line. The weight sorter 1 is sequentially loaded with a predetermined interval in the direction of arrow A, such as meat, fish, processed food, and pharmaceuticals. The weight of the weighing object W is measured, and the obtained measurement value (hereinafter referred to as a measurement value) is output as a measurement result.

  Further, the weight sorting apparatus 1 determines the object to be weighed W as a non-defective product or a defective product depending on whether or not the measured value is within the range of the reference value. Furthermore, the weight sorting apparatus 1 determines the weight rank of the object to be weighed W corresponding to a plurality of reference values based on the obtained measured values.

  Further, the measurement result, the pass / fail determination result, and the weight rank determination result are displayed on the display unit 10, and a sorting signal based on the judgment result is output to the sorting unit 5 connected to the subsequent stage of the weight sorting device 1. It is like that. The sorting unit 5 sorts the objects to be weighed W according to the sorting signal output from the weight sorting device 1.

  Next, a detailed configuration of the weight sorting apparatus 1 will be described. As shown in FIGS. 1 and 2, the apparatus main body 2 includes a weighing unit 21, a general control unit 7, a display unit 10, a setting unit 11, and a storage housing 2 a that stores these units. Has been.

  The transport unit 3 transports the object W to be weighed in from the belt conveyor 14 in the direction of arrow A under predetermined transport conditions. The object to be weighed W is conveyed by being accelerated or decelerated so as to have an optimum speed for measurement by the running conveyor 31, further conveyed by the weighing conveyor 32, and the weight is measured by the weighing unit 21 while being conveyed. It has become so.

  The weighing conveyor 32 conveys an object to be weighed under predetermined conveyance conditions. In addition, the object to be weighed W is further transported to the sorting unit 5 at the subsequent stage after weighing and is sorted.

  The transport unit 3 includes a running conveyor 31 and a weighing conveyor 32. The run-up conveyor 31 performs the run-up of the object to be weighed W before the object to be weighed W conveyed from the preceding belt conveyor 14 moves to the weighing conveyor 32, and includes two rollers 31a and 31c, And an endless conveying belt 31b wound around the roller.

  The weighing conveyor 32 is supported by the upper part of the weighing unit 21 for weighing the workpiece W, and includes two rollers 32a and 32c, an endless conveying belt 32b wound around these rollers, and a roller 32c. It is comprised with the motor which is not shown in figure which drives. The roller 32c is rotationally driven by a motor.

  The carry-in sensor 4 is disposed between the run-up conveyor 31 and the weighing conveyor 32, and includes a transmission photoelectric sensor including a pair of light projecting units 4a and light receiving units 4b. The light projecting unit 4a is disposed on the apparatus main body 2 side of the transport belt 32b, and the light receiving unit 4b is disposed on the other side surface of the transport belt 32b so as to face the light projecting unit 4a.

  The carry-in sensor 4 indicates that the object to be weighed W has started to be loaded when the object to be weighed W passes between the light projecting part 4a and the light receiving part 4b and the light receiving part 4b is shielded by the object to be weighed W. Is supposed to be detected. The carry-in start signal detected by the carry-in sensor 4 is output to the general control unit 7 in the apparatus main body 2.

  The weighing unit 21 is a load sensor that supports the weighing conveyor 32 and outputs a weighing signal based on the load of the workpiece W. The weighing unit 21 has a configuration of an electric resistance wire type balance (load cell), and measures the load applied to the weighing unit 21 while the workpiece W is being conveyed by the weighing conveyor 32.

  The weighing section 21 has a metallic strain body (not shown) and a bridge circuit made of an electric resistance wire (strain gauge) attached to a stress concentration portion of the strain body. The weighing unit 21 receives a load and deforms the stress concentration portion of the strain generating body, whereby the electric resistance wire is compressed and the electric resistance value is decreased, and the electric resistance wire is expanded and the electric resistance value is increased. Since the resistance value of the bridge circuit changes, this change in resistance value is measured as a weighing signal.

  The strain body has a fixed end and a free end, and the fixed end is fixed to the fixed base, and the lower end of the support portion 21a that receives the load of the weighing conveyor 32 is connected to the free end. . As the weighing unit 21, an electromagnetic balance type balance (force balance) or a differential transformer type balance may be used.

  The weighing unit 21 is provided with an environment measuring unit 100. The environment measuring unit 100 measures physical quantities such as vibration and temperature exerted on the weighing unit 21 by the installation environment of the weight sorting apparatus 1, and the measured data is stored in the environment. Output as data. A detailed configuration of the environment measuring unit 100 will be described later.

  The comprehensive control unit 7 includes a signal processing unit 71, a weighing unit 72, a storage unit 73, a control unit 74, a selection unit 76, and a mode switching unit 77.

  As shown in FIG. 3, the signal processing unit 71 includes an amplifier 94, an A / D converter 96, and a filter 97. The weighing signal from the weighing unit 21 is amplified by the amplifier 94, and the amplified signal is obtained. Digital conversion is performed by the A / D converter 96, and the digitally converted signal is filtered by the filter 97.

  Specifically, the signal processing unit 71 performs filter processing on the weighing signal from the weighing unit 21 using a filter selected from a plurality of low-pass filters of different types and characteristics, and signals only the low-frequency component of the weighing signal. It is made to pass through as a processed weighing signal.

  Note that there may be one low-pass filter selected by the signal processing unit 71 or a combination of a plurality of low-pass filters. As this low-pass filter, there are a FIR (Finite Impulse Response) filter and an IIR (Infinite Impulse Response) filter.

  The FIR filter is a finite impulse response filter that outputs a fixed time (finite time) when an impulse response waveform is input, and the IIR filter is an infinite impulse response that outputs an attenuation waveform of the impulse response waveform infinitely. It is a filter.

  Here, the FIR filter constitutes a low-pass filter that passes a predetermined low-frequency component with respect to the weighing signal converted into a digital signal by the A / D converter 96, and performs a simple averaging process or a known window function. The weighted averaging process used is performed.

  The IIR filter is an analog that directly receives a weighing signal (analog weighing signal) from the weighing unit 21 and outputs a processed signal to the A / D converter 96 using hardware whose characteristics can be changed, such as a switched capacitor filter. You may comprise by a filter and you may comprise by the digital filter which receives the digital weighing signal from the A / D converter 96.

  Further, the signal processing unit 71 includes a correction unit 78, and the correction unit 78 corrects the weighing signal based on the fluctuation amount of the environmental data measured by the environment measurement unit 100. The correction unit 78 corrects the fluctuation amount smaller than the fluctuation amount of the environmental data, which becomes an influence limit described later as an allowable range, as a correction limit.

  The correction unit 78 includes a correction signal generation unit 78A and a signal synthesis unit 78B. The correction signal generation unit 78A generates a correction signal for the environmental data output from the environment measurement unit 100. The signal synthesizer 78B synthesizes the correction signal with the weighing data.

  For example, when the environmental data is vibration, the correction signal generation unit 78A uses a response signal of the control target model with respect to the vibration signal, and generates a correction signal for removing the vibration effect from the weighing signal output from the weighing unit 21. Generate.

  Then, the signal synthesis unit 78B corrects the correction signal (FIG. 4B) generated by the correction signal generation unit 78A with respect to the weighing signal mixed with the vibration component output from the weighing unit 21 (see FIG. 4A). Is added in the opposite phase or subtracted in the same phase, thereby removing the vibration component from the weighing signal output from the weighing unit 21. Thereby, as shown in FIG.4 (c), the weighing signal from which the vibration influence was removed is obtained.

  Note that the signal processing unit 71 also corrects the drift of the weighing signal due to temperature fluctuations at predetermined time intervals for temperature fluctuations within a predetermined correction limit. The predetermined time that is the interval for performing correction in this case corresponds to the predetermined period of the present invention.

  The weighing unit 72 calculates (gram-converts) the measured value of the workpiece W based on the signal-processed weighing signal output from the signal processing unit 71. Individual measurement values calculated by the measurement unit 72 are stored in the storage unit 73 as calculation data.

  Further, in the weighing unit 72, after a predetermined reference time Tk has elapsed as shown in FIG. 5B, after the carry-in sensor 4 detects that the object to be weighed W has been carried into the weighing conveyor 32, A measured value is calculated for the object W to which the weighing signal is output from the weighing unit 21.

  Here, the reference time Tk is detected by the loading sensor 4 that the object to be weighed W has started to be loaded onto the weighing conveyor 32, and then the weighing object W is completely transferred to the weighing conveyor 32, and further from the weighing unit 21. This is the time required for the output weighing signal to stabilize.

  More specifically, the reference time Tk is the speed of the weighing conveyor 32 (m / min), the length of the weighing conveyor 32 in the direction of arrow B (mm), and the length of the weighing object W in the direction of arrow B (the direction of conveyance of the object W) ( mm), the size of the workpiece W, the processing capacity of the line, and other conditions.

  Further, as shown in FIG. 5B, when the reference time Tk elapses, the object W is moved by L1 from the loading start detection position P0 to the mass measurement position Ps as shown in FIG. 5A. The measurement is performed after the mass measurement position Ps.

  The calculation of the measured value is performed in a measurement period Ts (see FIG. 5B) after the reference time Tk elapses until the workpiece W is unloaded from the weighing conveyor 32. This measurement period Ts corresponds to a predetermined period in the present invention.

  In the weighing unit 72, inspection conditions (parameters) such as the measurement range, measurement capability, and inspection accuracy are selected according to the type (particularly size) of the object to be weighed W. Depending on the type of the weighing object W, for example, the measurement range is selected from 6 g to 600 g, and the measurement capability is selected at a maximum of 150 pieces / min.

  In this case, the reference time Tk per object W is set to a minimum of 400 msec, and the reference time Tk may be 400 msec or more. It is set according to capacity, production and other conditions.

  The storage unit 73 includes a storage medium and the like. The condition parameters including the predetermined transport condition of the object W to be weighed by the weighing conveyor 32 and the predetermined signal processing condition of the signal processing unit 71 are the types of the object to be weighed W. It corresponds to memorize.

  The storage unit 73 stores a conveyance speed and LPF (Low Pass Filter) characteristics corresponding to each product number assigned to each product type of the object to be weighed W. The storage unit 73 stores upper and lower reference values as a non-defective range for determining the quality of the object W.

  Here, the conveyance speed is the speed of the conveyance unit 3 that conveys the workpiece W, and the LPF characteristic indicates what kind of characteristic the low-pass filter is, and the non-defective range is determined as non-defective. This is the range of the weight of the object W to be measured.

  The stored information is stored in advance by a setting operation from the setting unit 11 or connection with an external device. The storage unit 73 stores various data such as measurement values and pass / fail judgment results.

  The control unit 74 reads a predetermined transport condition and a predetermined signal processing condition from the storage unit 73 according to the type of the object to be weighed W, and controls the weighing conveyor 32 and the signal processing unit 71, respectively.

  The control unit 74 controls the transport unit 3 and the signal processing unit 71 by sequentially switching condition parameters corresponding to a plurality of types stored in the storage unit 73. In addition, the control unit 74 drives and controls the rotation speed (rpm) of a motor (not shown) so as to control the conveyance speed of the workpiece W by the conveyance unit 3.

  The selection unit 76 includes a determination circuit and the like, and the influence based on the quality determination result based on the comparison between the measurement value calculated by the measurement unit 72 and the quality determination reference value and the influence degree calculated by the influence degree calculation unit 120. Based on both the presence / absence determination results, the direction in which the object W is selected is determined and a selection signal is output. In addition, the sorting signal is output to the sorting unit 5 connected to the subsequent stage of the weight sorting device 1 so that the weighing object W is sorted as a non-defective product and a non-defective product due to weighing, and a weighing product subjected to environmental changes. ing. Further, these determination results are output to the storage unit 73, and the determination results for each object W are stored. The detailed configuration of the selection unit 76 will be described later. In addition to the pass / fail determination using the measured value calculated by the weighing unit 72, a selection signal may be output based on the rank determination result of the weight rank divided into a plurality of divisions.

  The mode switching unit 77 issues a command to the control unit 74, and switches the operation mode of the weight sorting apparatus 1 between the main operation mode and the setting mode. Here, the actual operation mode is a normal operation mode in which the weight sorting device 1 performs weighing, weight calculation, and pass / fail judgment of the workpiece W, and the setting mode is for operation in the operation mode. This is an operation mode for confirming whether or not various parameters can be set and operation in the operation mode can be performed normally.

  As shown in FIG. 1, the display unit 10 is provided at the upper end of the apparatus main body 2 on the transport unit 3 side, and is configured by a display device such as a liquid crystal display. The display unit 10 displays the operation state of the weight sorting device 1, the measured value of the object to be weighed W, the determination result, and displays related to parameter setting and operation confirmation. The display unit 10 and the setting unit 11 may be integrated as a touch panel so that numbers, characters, and the like displayed on the display unit 10 are input from the setting unit 11 by a touch operation.

  The distribution unit 5 is connected to the subsequent stage of the weight sorting device 1 and includes a distribution mechanism unit 5a and a conveyor belt 5b. The distribution mechanism unit 5a is configured by a flipper mechanism that can distribute in three directions.

  The distribution mechanism unit 5a only needs to be able to distribute in three directions, a non-defective product by measurement and a defective product, and a measured product that has undergone environmental changes. For example, a dropout mechanism, an air jet mechanism, an extrusion mechanism, etc. You may comprise with the distributed distribution mechanism.

  The conveyor belt 5b is composed of a roller 5c, a roller (not shown) disposed opposite to the roller 5c, and an endless conveyor belt wound around these rollers. The weighing object W is conveyed downstream at a predetermined speed.

  In the present embodiment, as shown in FIG. 1, the weight sorting apparatus 1 includes an environment measurement unit 100 and an influence degree calculation unit 120.

  As shown in FIG. 6, the environment measuring unit 100 measures a physical quantity acting on the weighing unit 21 and outputs it as environment data. The environment measuring unit 100 includes a vibration sensor 101, an atmospheric pressure sensor 102, a temperature sensor 103, and a humidity sensor 104.

  Here, the weight sorting device 1 is subject to vibrations generated by other devices and vehicles, atmospheric pressure fluctuations caused by opening and closing doors of installed rooms, and temperature fluctuations and humidity fluctuations due to heat generated by other devices and the own machine. Works. Such vibrations, pressure fluctuations, temperature fluctuations, and humidity fluctuations may adversely affect the measurement of the load of the object W to be weighed by the weighing unit 21.

  Specifically, even if the weighing signal is corrected by the signal processing unit 71, if the change in the environment is sudden or exceeds the correction range, the corrected weighing signal is displayed. The effects of environmental changes remain. For this reason, the to-be-measured object W which should be determined to be inferior goods will be determined to be non-defective. Therefore, in the weight sorting apparatus 1, the sorting unit 76 sorts the objects to be weighed under the influence of the environmental variation based on the vibration, atmospheric pressure variation, temperature variation, and humidity variation measured by the environment measuring unit 100. The sorting signal for output can be output.

  The vibration sensor 101 is provided at a fixed end of the strain generating body of the weighing unit 21 and measures vibration (displacement) acting on the weighing unit 21. The vibration sensor 101 is composed of an acceleration sensor having one or more axes having the same frequency characteristics as the weighing unit 21.

  In the present embodiment, the vibration sensor 101 is composed of one triaxial acceleration sensor that detects triaxial accelerations of the X axis, the Y axis, and the Z axis, and the X axis direction of vibration at the fixed end of the strain generating body. The vibration component in each direction of the Y-axis direction and the Z-axis direction is detected and output.

  Here, the X-axis direction is the conveyance direction of the object to be weighed by the belt conveyor 14, and the Y-axis direction is a direction (width direction of the belt conveyor 14) perpendicular to the conveyance direction of the object to be weighed W on the horizontal plane. Yes, the Z-axis direction is the vertical direction. Further, as the vibration sensor 101, an acceleration sensor having a natural frequency higher than the natural frequency of the strain body is used.

  The atmospheric pressure sensor 102 measures the atmospheric pressure acting on the weighing unit 21 and is composed of an absolute pressure sensor that measures the absolute pressure of the atmospheric pressure. The temperature sensor 103 measures the temperature acting on the weighing unit 21, and the humidity sensor 104 measures the humidity acting on the weighing unit 21.

  Each of the vibration sensor 101, the atmospheric pressure sensor 102, the temperature sensor 103, and the humidity sensor 104 includes an A / D converter and a sensitivity correction unit (not shown). The A / D converter converts the detected signal from an analog signal to a digital signal by the A / D converter. The sensitivity correction unit performs amplitude correction on the detected signal with a predetermined sensitivity ratio.

  The influence degree calculation unit 120 receives the environmental data measured by the environment measurement unit 100, and calculates the influence degree that the fluctuation of the environmental data has on the measurement value. The influence degree calculation unit 120 calculates the influence degree so that the influence degree increases as the fluctuation amount of the environmental data in the predetermined period increases.

  Here, the fluctuation amount of the environmental data includes the fluctuation amount of the displacement from the vibration sensor 101, the fluctuation amount of the pressure from the atmospheric pressure sensor 102, the fluctuation amount of the temperature from the temperature sensor 103, and the fluctuation amount of the humidity from the humidity sensor 104. It is.

  The influence degree calculated by the influence degree calculation unit 120 is, for example, an influence level obtained by stepwise evaluating the amount of change in environmental data during a predetermined period. For example, as shown on the right side of FIG. 7B, the influence degree calculation unit 120 evaluates the fluctuation amount of the environmental data in five stages from the influence level 1 to the influence level 5. The graphs of FIGS. 7A and 7B show the weighing signal and the degree of influence when there is a temperature variation as environmental data. In this case, the influence level of FIG. It is expressed by an index such as the rate of change (%) based on temperature. Specifically, values such as Level 1 ± 2%, Level 2 ± 3%, Level 3 ± 5%, Level 4 ± 8% are associated, and the temperature at the start of operation is used as a reference value. The temperature fluctuation level is set.

  The influence degree calculated by the influence degree calculation unit 120 is, for example, a converted value obtained by converting the fluctuation amount of the environmental data in a predetermined period into a gram as an increase / decrease in the measured value.

  The conversion value as the influence degree calculated by the influence degree calculation unit 120 is, for example, a graph of the influence degree shown in FIG. In FIG.7 (b), the influence degree as the converted value converted into grams is shown on the vertical axis, and time is shown on the horizontal axis. This graph shows that there are two portions where the degree of influence is outside the allowable range.

  In FIG. 7B, the measurement period Ts as the predetermined period includes a part where the influence is outside the allowable range. If there is such an influence degree that is out of the allowable range within the measurement period Ts, the measurement value calculated by the measurement unit 72 is not calculated correctly.

  Note that when the influence degree is calculated from vibration, the converted value of the influence degree at a certain time corresponds to the displacement amount measured by the vibration sensor 101. Therefore, the influence degree of vibration repeats fluctuations in one direction and the other direction in a short period of time compared to the influence degree of temperature and humidity. As for the degree of influence of atmospheric pressure, the atmospheric pressure fluctuation due to opening and closing of the door repeats fluctuation in one direction and the other direction in a short period of time.

  As shown in FIG. 8, the selection unit 76 includes a measurement determination unit 81 that performs pass / fail determination based on whether or not the measurement value is within a predetermined reference range, and whether or not the influence is within a predetermined allowable range. An influence determination unit 82 that determines whether or not there is an influence on the determination of the measurement determination unit 81 is provided.

  When the result of the influence determination unit 82 has an influence, the sorting unit 76 assumes that the determination of the measurement determination unit 81 is performed with the measurement value affected by the environmental change, and the measurement value affected by the environmental change. A sorting signal for sorting the weighing object W for which the pass / fail judgment has been performed in a predetermined sorting direction is output, and when the determination result of the influence determination unit 82 has no influence, according to the determination result of the weighing determination unit 81, A sorting signal for sorting in a sorting direction according to another pass / fail judgment different from the sorting direction of the weighing object W that has been judged pass / fail by the measured value affected by the environmental variation is output.

  That is, the determination result of the influence determination unit 82 is prioritized over the determination result of the measurement determination unit 81. When there is an influence, the pass / fail determination is made based on the measurement value subjected to the environmental change without being influenced by the determination result of the measurement determination unit 81. A sorting signal for sorting the measured object W is output.

  When the weighing determination unit 81 receives the weighing value as the weight of the weighing object W output from the weighing unit 72, the weighing determination unit 81 reads the upper limit value and the lower limit value of the weight stored in advance in the storage unit 73, and calculates the weighing object. The weight of W is compared with the upper limit value and the lower limit value, respectively, and it is determined whether or not the weight of the object to be weighed W is within the allowable weight range determined by the upper limit value and the lower limit value. Yes.

  The influence determination unit 82 determines that there is an influence when the influence degree is out of a predetermined allowable range. For example, when the influence of the object to be weighed W deviates from the allowable range during the measurement period Ts as shown in FIG. 7B, the end of the measurement period Ts as shown in FIG. 7C. It is determined that there is an influence at the timing. Note that the degree of influence outside the allowable range outside the measurement period Ts is not determined in a period outside the determination target.

  Here, it is assumed that the measured value of the object to be weighed W output from the weighing unit 72 is g1 as shown in FIG. In this case, if it is affected by environmental fluctuations, the original measured value is g2, and the measured value has changed from outside the reference range to g1 within the reference range due to environmental fluctuations. The to-be-measured item W is judged as a non-defective product as a non-defective product. In such a case, if the degree of influence is out of the predetermined allowable range, the influence determination unit 82 outputs a selection signal for selecting as a weighing product that has undergone environmental fluctuation. If the degree of influence is within a predetermined allowable range, the degree of influence is corrected by the correction unit 78 described above, and the measurement value g2 of the original object W is output from the measurement unit 72 as a measurement value. Therefore, it is determined as a defective product.

  When the configuration without the correcting unit 78 is used, if the selection direction determined based on the influence subtraction value obtained by subtracting the converted value from the measurement value does not match the selection direction determined based on the measurement value, The sorting direction may be determined by considering it as a defective product. In the case of FIG. 9, the weighing value is g1, the influence subtraction value obtained by subtracting the converted value from the weighing value is g2, the sorting direction determined based on g1 is the good product direction, and the sorting direction determined based on g2 is the defective product direction. Thus, the sorting directions do not match and are sorted as defective products. By determining in this way, it is possible to prevent a defective product from being erroneously selected as a non-defective product.

  The quality determination result determined by the sorting unit 76 is output to the display unit 10 and displayed as a non-defective product or a defective product. Further, when it is determined that there is no influence, a sorting signal corresponding to the pass / fail judgment result is output to the sorting unit 5 connected to the subsequent stage of the weight sorter 1 so that the object to be weighed W is sorted as a non-defective product or a defective product. It has become. Further, the pass / fail judgment result is output to the storage unit 73, and the pass / fail judgment result for each object W is stored.

  In addition, the degree of influence of the inspected object W is stored in the storage unit 73. The influence degree memorize | stored in the memory | storage part 73 is displayed on the display part 10 in the aspect as shown in FIG. 10 with the influence degree limit which shows the tolerance | permissible_range.

  In FIG. 10, a data display area 10 i is provided in the left half of the display unit 10, and environmental data or a measurement waveform measured by the environment measurement unit 100 is displayed in the data display area 10 i. In FIG. 10, vibration data is displayed as environmental data in the data display area 10i.

  A display switching button 10a is provided at the lower part of the display unit 10. By operating the display switching button 10a, the data to be displayed in the data display area 10i is switched to any of vibration, temperature and measurement waveform. Or switching to one of vibration and temperature, or switching to one of predetermined environmental data and a measurement waveform.

  In addition, an overlay button 10b is provided below the display unit 10, and two or more data can be superimposed on the data display area 10i by operating the overlay button 10b. For example, vibration, temperature, and measurement waveform can be superimposed, vibration, measurement waveform can be superimposed, and temperature and measurement waveform can be superimposed.

  Further, an enlargement / reduction button 10c is provided at the lower part of the display unit 10, and the display magnification of the display content in the data display area 10i can be changed by operating the enlargement / reduction button 10c.

  Further, a return button 10d is provided at the lower part of the display unit 10, and the installation environment monitor function for displaying environmental data in the data display area 10i can be terminated by operating the return button 10d.

  Further, a front button 10e and a next button 10f are provided at the lower part of the display unit 10, and environmental data or measurement waveform data for the previous object W is displayed in the data display area by operating the front button 10e. When the next button 10f is operated, the environmental data or the measured waveform data for the next object W is displayed in the data display area 10i.

  Further, a determination result display area 10g is provided at the upper right of the display unit 10, and a quality determination result is displayed in the determination result display area 10g. FIG. 10 shows that the character “NG” is displayed in the determination result display area 10g and the pass / fail determination result is bad.

  As described above, the weight sorting apparatus 1 according to the present embodiment is measured by the environment measuring unit 100 that measures the physical quantity that can act on the weighing unit and can change the weighing signal as environmental data, and the environment measuring unit 100 measures. An influence degree calculation unit 120 that receives environmental data and calculates an influence degree to the measurement value according to a change in the environmental data in a predetermined period, and a selection part based on whether the influence degree is within a predetermined allowable range. And an influence determining unit 82 that determines whether or not there is an influence on the determination 76.

  The sorting unit 76 outputs a sorting signal for sorting in one sorting direction when the determination result of the influence determining unit 82 has an influence, and from the weighing unit 72 when the determination result of the influence determining unit 82 has no influence. A sorting signal for sorting in another sorting direction is output according to the determination by the measured value.

  With this configuration, the sorting unit 76 outputs a sorting signal for sorting in one sorting direction when the determination result of the influence determining unit 82 has an influence, and the measured value when the determination result of the influence determining unit 82 has no influence. Accordingly, since a sorting signal for sorting in another sorting direction is output, it is possible to prevent a defective product from being erroneously sorted as a non-defective product due to environmental fluctuations that affect weighing.

  Further, in the weight sorting apparatus 1 according to the present embodiment, the influence degree calculation unit 120 calculates, as the influence degree, a conversion value obtained by converting the fluctuation amount of the environmental data in the predetermined period as the increase / decrease amount of the measured value in grams.

  With this configuration, the influence calculation unit 120 calculates the conversion value obtained by converting the fluctuation amount of the environmental data in the predetermined period as the increase / decrease amount of the measurement value as the influence value, so that the user can change the increase / decrease amount of the measurement value. Since the degree of influence can be grasped as a converted value converted into grams, the allowable range used by the influence determination unit 82 can be appropriately set. For this reason, it is possible to prevent the determination by the influence determination unit 82 from becoming unnecessarily strict.

  Further, in the weight sorting apparatus 1 according to the present embodiment, the sorting unit 76 performs the sorting determined based on the sorting direction and the measured value determined based on the effect subtraction value obtained by subtracting the converted value within the allowable range from the measured value. If the direction does not match, the sorting direction is determined by considering it as a defective product.

  With this configuration, when the selection direction determined based on the influence subtraction value and the selection direction determined based on the measurement value do not match, the determination of the selection direction may change even if the influence is small. For this reason, it is possible to more reliably prevent the defective product from being erroneously selected as a non-defective product due to environmental changes by determining the sorting direction while regarding the workpiece W as a defective product.

  Further, in the weight sorting apparatus 1 according to the present embodiment, the weighing unit 21 includes the transport unit 3 that transports the workpiece W, and the influence calculation unit 120 is the sample to be measured that is measured by the environment measurement unit 100. A correction unit 78 calculates a converted value based on the fluctuation amount of the environmental data during a period in which W is on the transport unit 3, corrects the measured value using the converted value within the allowable range, and outputs the corrected value to the selection unit 76. .

  With this configuration, when the converted value calculated based on the fluctuation amount of the environmental data has a strong correlation with the error of the measured value, the converted value can be used to correct the measured value. As a result, the accuracy of the measurement value can be improved.

  Moreover, in the weight selection apparatus 1 according to the present embodiment, the influence degree calculation unit 120 calculates the influence level represented by the stepwise level value as the influence degree, and the influence determination unit 82 determines the predetermined level among the influence levels. The level value is set as the allowable range.

  With this configuration, the user can easily store stepwise influence level values (level 1 to level 4 etc.) using an index such as the measured environmental data variation rate and select the level value. An allowable range can be set.

  Moreover, the weight selection apparatus 1 according to the present embodiment includes a storage unit 73 that stores the degree of influence at a predetermined timing, and a display unit 10 that displays the degree of influence stored in the storage unit together with an allowable range.

  With this configuration, the user confirms the influence level and the allowable range on the display unit 10 to identify the cause of the influence level exceeding the allowable range and improve the manufacturing facility in which the weight sorting apparatus 1 is installed. be able to.

  As described above, the weight sorting apparatus according to the present invention has an effect of preventing erroneous determination of a defective product as a non-defective product, and weighs objects to be weighed such as meat, fish, processed food, and pharmaceutical products. Thus, it is useful as a weight sorting device for judging pass / fail.

DESCRIPTION OF SYMBOLS 1 Weight sorter 3 Conveying part 10 Display part 21 Weighing part 32 Weighing conveyor 71 Signal processing part 72 Weighing part 73 Storage part 76 Sorting part 78 Correction part 81 Weighing judgment part 82 Influence judgment part 100 Environmental measurement part 120 Influence degree calculation part Ts Measurement period (predetermined period)
W Object to be weighed

Claims (6)

A weighing unit (21) for outputting a weighing signal in accordance with the load of the objects to be weighed (W) that are sequentially inserted;
A weighing unit (72) that receives the weighing signal and calculates a measurement value of the object to be weighed;
In a weight selection apparatus comprising: a selection unit (76) that determines a direction of selecting the object to be measured based on the measurement value and outputs a selection signal;
An environmental measurement unit (100) that acts on the weighing unit and measures, as environmental data, a physical quantity that can change the weighing signal;
An influence calculation unit (120) that receives the environmental data measured by the environmental measurement unit and calculates an influence on the measurement value according to a change in the environmental data in a predetermined period;
An influence determination unit (82) that determines whether or not there is an influence on the determination of the selection unit based on whether the degree of influence is within a predetermined allowable range,
The selection unit outputs a selection signal for selection in one selection direction when the determination result of the influence determination unit has an influence, and when the determination result of the influence determination unit has no influence, the selection unit outputs the selection signal. A weight sorting apparatus that outputs a sorting signal for sorting in another sorting direction according to determination by a measured value.   The said influence degree calculation part calculates the conversion value which carried out the gram conversion of the fluctuation | variation amount of the said environmental data in the said predetermined period as the increase / decrease amount of the said measured value as said influence degree. Weight sorting device.   The selection unit determines that the selection direction determined based on the subtraction value obtained by subtracting the converted value within the allowable range from the measurement value does not match the selection direction determined based on the measurement value. The weight sorting apparatus according to claim 2, wherein the sorting direction is determined by considering it as a non-defective product. The weighing section has a transport section (3) for transporting the object to be weighed,
The influence calculation unit calculates the converted value based on a variation amount of the environmental data during a period in which the object to be measured measured by the environment measurement unit is on the transport unit;
The weight selection device according to claim 2, further comprising a correction unit (78) that corrects the measurement value using the converted value within the allowable range and outputs the corrected measurement value to the selection unit. The influence calculation unit calculates an influence level represented by a stepwise level value as the influence,
The weight selection apparatus according to claim 1, wherein the influence determination unit sets a predetermined level value among the influence levels as the allowable range. A storage unit (73) for storing the influence degree at a predetermined timing;
The weight selection apparatus according to any one of claims 1 to 5, further comprising a display unit (10) for displaying the influence degree stored in the storage unit together with the allowable range.

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