JPS60113117A - Weigher - Google Patents

Abstract

PURPOSE:To simplify span adjustment by dividing a set weight of an article, whose weight is known, by a weighed signal of this article to operate a proportional constant and storing the proportional constant in a memory and multiplying this proportional constant and a weighed signal of an unknown weight. CONSTITUTION:The weight of the article whose weight is known, for example, a standard weight to be placed on a scale (omitted in a figure) is set by a constant setting dip switch 22, and the weighed signal subjected to zero point correction of the standard weight placed on the scale is supplied to a divider 24, and the set weight by the switch 22 is divided by this weighed signal to calculate a span coefficient. A span adjusting switch 28 is closed to store the span coefficient in a memory 26 for span coefficient, and the switch 28 is opened, and the standard weight is removed, and an article whose weight is unknown is placed on the scale, and a weighed signal subjected to zero point correction from a substractor 14 is supplied to a multiplier 16 together with the span coefficient from the memory 26, and span adjustment is performed, and the multiplication result is displayed on a display part 20.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a weighing device, and particularly to one that performs span correction.

Conventionally, there has been a scale capable of the above-mentioned span correction as shown in FIG. In the figure, 2 is a load cell that generates an analog weighing signal proportional to the weight of an article placed on a mounting table (not shown). Reference numeral 4 denotes an excitation voltage generating section that supplies an excitation voltage to the load cell 2. The analog weight signal from the load cell 2 is amplified by the amplifier 6,
/D converter 8 converts it into a digital weight signal (hereinafter, the digital weight signal will be simply referred to as a weight signal).

The weighing signal of the weight changer 8 when no article is placed on the platform is stored in the zero point memory memo 1/2 via the switch IO, and this signal is stored in the zero point memory memo 1/2 when no article is placed on the platform. The subtractor 14 from the weight signal from the A/D converter 8 in the state
is subtracted by and zero point correction is performed. The zero point corrected weighing signal is sent to a span coefficient di) by a multiplier 16.
It is multiplied by the span coefficient set to 18,
It is displayed on the display section 20. By the way, this was done by operating the dip switch 18 through trial and error so that the span coefficient dip switch 18 had a known weight. However, since such operations are performed by trial and error, they can only be performed by experienced operators, and even for experienced operators it takes a considerable amount of time, resulting in low work efficiency.

The purpose of this invention is to provide a weighing device that allows anyone to easily adjust the span.

Therefore, the present invention includes a weighing section that generates a weighing signal proportional to the weight of the loaded article, and a constant section in which the weight of the article whose weight is known to be loaded on the weighing section is set. , a dividing unit that calculates a proportionality constant by dividing the set weight of the constant unit by a weighing signal when an article of known weight is loaded; a memory that stores the proportionality constant; and a calculation unit of the weighing unit. It is comprised of a multiplier that multiplies the multiple signal by the proportionality constant of the memory.

With this configuration, when an article whose weight is known is loaded onto the weighing section, the dividing section automatically calculates a proportionality constant and stores it in the memory. After that, when the goods are loaded in the weighing section (
The weight signal is multiplied by the proportionality constant, and the span-adjusted weight value is displayed on the display. Therefore, the operator can store the proportionality constant in the memory simply by loading an article of known weight onto the weighing section, and anyone can easily set the proportionality constant.

Hereinafter, this invention will be explained in detail based on two embodiments shown in FIGS. 2 to 7. FIG. 2 shows a first embodiment. In addition, in the same figure, parts equivalent to those of the conventional one are given the same reference numerals, and explanations thereof will be omitted. Reference numeral 22 denotes a constant setting switch, in which the weight of an article whose weight is known to be loaded on the platform, such as a standard weight, is set. 24 is a divider which divides the set weight of the constant setting dip switch 22 by the zero point corrected weighing signal. Reference numeral 26 denotes a span coefficient memory, which stores the denominator value of the divider 24 when the span adjustment switch 28 is closed;
supply to.

Therefore, when the span adjustment switch 2 is closed and the above-mentioned standard weight is placed on the platform, the zero-corrected weight signal is supplied to the divider 24, and at the same time, the divider 24 is supplied with the constant setting signal. For example, the weight of a standard weight set to the dip switch 22 is also supplied, and the divider 24 divides the set weight of the standard weight by the zero point corrected weight signal to calculate a span coefficient. This span coefficient is the span coefficient memory 2.
6 is stored. Then, open the span adjustment switch.

In this state, when the standard weight is removed and an article of unknown weight is placed on the platform, the subtracter 14 supplies the zero-corrected weight signal to the multiplier 16, and at the same time, the span coefficient memory 26 outputs the span coefficient. The coefficients are provided to multiplier 16. The multiplier 16 multiplies the zero point corrected weighing signal by a span coefficient to adjust the span of the weighing signal. The span-adjusted weighing signal is displayed on the display unit 20.

A second embodiment is shown in FIGS. 3 to 7. In this embodiment, span adjustment is performed by polygonal line approximation as shown in FIG. In other words, up to 1ooog is a straight line 3o
Adjust the span according to 100o to 2000o.
Up to g, perform span adjustment according to straight line 32, and
From 0 to 3000g, the Teshan adjustment is carried out along the straight line 34.

FIG. 4 shows a schematic block diagram of this embodiment.

In the same figure, 3o is the span adjustment switch
o" key, "2000J key, r'3ooo" key.
It has two keys. Press the +0OOJ key on the inside of this span adjustment switch 3o, and set the weight to 1000 on the platform.
When a standard weight of g is placed, the subtracter 14 generates a weight signal w1 corresponding to 1000 g, and the weight signal w1 is stored in the weight memory 32. At the same time, the weight 1000 set to this value is supplied from the constant section 34 to the calculation section 36. The calculation unit 36 is also supplied with the weighing signal W1, and the calculation unit 36 receives l O
OO/Vl is calculated to calculate the span coefficient (the gradient of the straight line 3o in FIG. 3). This span coefficient M1 is stored in the span coefficient memory 38.

Similarly, when the key "2oOo" of the span adjustment switch 3o is pressed and a 2000g standard weight is placed on the platform, the training signal w2 at that time is stored in the weight memory 4o.

At the same time, the set weight 2000 is supplied from the constant section 42 to the calculation section 36. The arithmetic unit 36 is supplied with wl from the weight memory 32 and w2 from the subtractor 14, and the result is 1000/(W2-
Wl) (7) Perform the calculation to calculate the span coefficient M2 (the gradient of the straight line 32 in FIG. 3). This span coefficient M2
is stored in the span coefficient memory 44.

Similarly, key 1-3000J of span adjustment switch 30
Press and place a 3000g standard weight on the platform.
The set weight “3000” is supplied from the constant unit 48 to the calculation unit 36. The calculation unit 36 receives W2 from the weight memory 40.
W3 is also supplied from the subtracter 14, and +000/(W3-W
2) and calculate the span coefficient M3 (straight line 3 in Figure 3).
Calculate the gradient of 4). This span coefficient M3 is stored in the span coefficient memory 50.

When an article of unknown weight is placed on the platform without pressing any key of the span adjustment switch 30, the weighing signal W is converted into the stored value vi+, W2, W2 of the weight memo IJ 32.40 in the comparator 52. compared to wi. If W4W+, the comparator 52 supplies the span coefficient M1 from the span coefficient memory 3 days to the arithmetic unit 54. The calculation unit 54 multiplies the weight signal W by the span coefficient M1 and supplies the result to the display unit 20.

If Wl<W(W2), the comparison unit 52 supplies the span coefficient M2 from the span coefficient memory 44 to the calculation unit 54.The calculation unit 54 is supplied with Wl from the weight memory 32, and (w−w+) - Performs the calculation of M2+1OOO and supplies it to the display unit 20.

If W2 (W), the comparison unit 52 supplies the span coefficient M3 from the span coefficient memory 50 to the calculation unit 54.

The calculation unit 54 is supplied with W2 from the weight memo 1J40, performs the calculation of (W-W2)·M3+2000, and supplies the result to the display unit 20.

FIG. 5 shows a block diagram when the embodiment of FIG. 4 is implemented using a microcomputer.

In the figure, a CPU 56 is supplied with a weighing signal from the A/D converter 8, and is also supplied with a switching signal from the winter panties adjusting switch 30. The CPU 56 processes these signals in accordance with the program stored in the ROM 5B while exchanging data with the RAM Mf 30.
The weight of the stolen span is displayed on the display section 20.

FIG. 6 shows a flowchart for setting the span coefficients M1'I M2 and M3. It is assumed that the weights of three types of standard weights, 1000, 2000, and 3000, are stored in the RAM 60 using a keyboard (not shown). In step 62, the span adjustment switch 30 key [10
Determine whether QOj is pressed. If it is pressed, in step 64 1000 is set to the current weight signal W (
LOOOG standard weight weighing signal) to calculate the span coefficient M1, and store this. Next, in step 66, the weighing signal W is stored as Wl, and the process returns to step 62.

When it is determined in step 62 that the key ``100OJ'' is not pressed, the process moves to step 68, and the key ``200J'' is pressed.
Determine whether or not is pressed. If it is pressed, in step 70, 1000 is divided by the weight signal W (weight signal of a standard weight of 2000 g) minus Wl to calculate the span coefficient M2 and store this. Next, in step 72, the weighing signal W is stored as W2, and in step 62
Return to

If the key "2000" has not been pressed on the 6th day, the process moves to step 74, and it is determined whether the key r3000J has been pressed. When pressed, in step 76, divide 1000 by the current weight signal W (3000 g standard weight weight signal) or (minus W2) to calculate the span coefficient MS, and store this. After step 76, the process returns to step 62. Also, when it is determined in step 74 that the key "3000J" is not pressed, the process returns to step 62.
, M3, etc. settings are completed. In addition, the key "1ooo",
Before or immediately after "2000" and "r30oo" are pressed, 1000g, 2000g, 300 respectively.
0g (7) A standard weight is placed on the platform. 'Next, FIG. 7 shows a flowchart for span adjustment when weighing an article whose weight is unknown. First, in step 7, when the weight signal W is more than w1, in step 80 the weight signal W is multiplied by the span coefficient Ml to calculate the span adjustment weight signal Y, and in step 82 Y is displayed. 20, and the process returns to step 78.

When the weighing signal W is not less than Wl in step 78,
In step 84, it is determined whether the weight signal W is less than or equal to w2. If it is less than W2, in step 86, the sum obtained by subtracting Wl from the transfer air weight signal W is multiplied by the span coefficient M2,
1000 is added to this multiplication value to calculate the span adjustment weight signal Y, and step 82 is executed as described above.

In step 84, when the weight signal W is below W2, the process moves to step 88, where the weight signal W minus W2 is multiplied by the span coefficient M3, 2000 is added to this multiplied value, and the span adjustment is calculated. Compute the superimposed signal Y and perform step 82 as described above.

As described above, according to this invention, the span coefficient is calculated and stored in the memory, so anyone can easily adjust the span.

In the first embodiment described above, the weight of the standard weight is set using the dip switch 22, but it may also be set in a memory separate from the span coefficient memory 26 using the numeric keypad. Also,
Conversely, in the second embodiment, the weight of the standard weight is set in the RAM 60 using the numeric keypad, but it may also be set using a delay switch. Although the first embodiment is constructed using a logic circuit, it may be constructed using a microcomputer as in the second embodiment.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of a conventional weighing device, Fig. 2 is a block diagram of a first embodiment of a weighing device according to the present invention, and Fig. 3 is a span adjustment principle underlying the second embodiment. , FIG. 4 is a schematic block diagram of the second embodiment, FIG. 5 is a block diagram of the second embodiment constructed using a microcomputer, and FIG. 6 is a block diagram of the second embodiment. FIG. 7 is a flowchart showing the process of calculating the span coefficient in the case of FIG. 5. FIG. 2.4...Measuring part, 22.34.42.48...Constant part, 24.36...Division part, 26.38.44.5
0...Memory, 16.54...Multiplication section. Patent applicant Yamato Seiko Co., Ltd. Agent Satoshi Shimizu and two others

Claims (1)

[Claims] (1) A weighing section that generates a weighing signal proportional to the weight of the loaded article, a constant section to which the weight of the article whose weight is known to be loaded on the weighing section is set, and a constant section that generates a weighing signal proportional to the weight of the loaded article; a division section that calculates a proportionality constant by dividing the set weight of the constant section by the weight signal of the weighing section when a known article is loaded; a memory that stores the proportionality constant; A weight training device comprising a multiplier that multiplies a weight signal by a proportionality constant stored in a memory.