JPH0449571Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a device for measuring the specific gravity of solids, and is used to determine the purity of gold, platinum, etc., for example.

(Prior art and its problems) Precious metals such as gold, silver and platinum are widely used for craft decoration or chemical industry.
Due to its rarity, it is extremely expensive. Therefore, when trading precious metals, especially craft ornaments, it is necessary to quickly determine their value. We are trying to distinguish between.

The conventional method for measuring specific gravity for this purpose, as shown in FIG. 2 suspends the object M to be measured and measures its weight W ₁ in the air (as shown in Fig. 4), then raises the lifting platform 5 to lift the object M to be measured.
completely immersed in water 3, its weight in water
Measure W ₂ . Based on this measurement result, S=W ₁
The specific gravity S is determined by calculating ÷(W ₁ −W ₂ ). For example, if W ₁ = 50.4g, W ₂ = 47.1g, S = 50.4
÷ (50.4-47.1) = 15.27, and it can be estimated from the specific gravity table (not shown) that it is 18K gold.

However, according to this conventional method, hanging items such as the hook 2 also enter the water, and due to the buoyancy caused by this, the weight W ₂ of the object M in the water is measured to be smaller than the actual weight, which causes an error. Therefore, accurate specific gravity cannot be determined. Moreover, if the object M to be measured is rod-shaped, chain-shaped, or coin-shaped, it must be tied with a thread-like material in order to hang it from the hook 2, and this thread-like material adds error. It was a difficult task that required a great deal of attention and time to operate the object M to be measured so that it did not come into contact with the container 3 and remained stationary and stable.

In addition, in order to measure the weight of the object to be measured underwater, it is necessary to move the container 2 up and down.
In order to move the water tank up and down, a fairly large-scale device is required, and no matter how sophisticated the device is, it is difficult to prevent the water in the tank from shaking.

For this reason, it takes time to raise the water tank and time for the shaking of the water caused by the rise of the tank to stop before measuring the underwater weight of the object to be measured. The problem is that it takes a considerable amount of time.

(Technical means for solving the problem) In view of the conventional problems, the present invention measures the specific gravity without suspending the object M to be measured, thereby eliminating errors caused by hanging objects such as hooks. remove,
In addition, the present invention provides an apparatus that facilitates and speeds up the work of measuring the weight of an object to be measured in the air and underwater, and that can perform measurements regardless of the shape of the object M to be measured. The technical means for this purpose includes a first container 12 containing the liquid L, a second container 13 that is accommodated in the first container 12 without contact and into which the liquid L in the first container 12 can freely flow in and out, and an aerial mounting section 15 for placing the object to be measured M in order to measure the gravity of the object to be measured M in the air; and a weighing device 17 for receiving and supporting the second container 13; The weighing device 17 includes a sensor 20 that converts the weight acting on the second container 13 into an electrical signal, and a measuring device M.
The output of the sensor 20 when the object M is placed on the aerial mounting section 15 and the object to be measured M are the same as those of the second container 1.
The sensor 2 when placed submerged in liquid
The measurement unit 21 measures the specific gravity of the object to be measured M based on the output of zero.

(Example) Hereinafter, an example of the present invention will be described based on the drawings.

In Figures 1 and 2, specific gravity measuring device 1
1 is a cylindrical first container 12 containing water L, and the first container 1 is accommodated in the first container 12 without contacting it.
A cylindrical second container 13 formed in a net shape so that the water L in the container can freely flow in and out;
A support part 14 is formed integrally with the container 12 to support it on the outside, and a lid body is attached to the upper opening 13a of the second container 13 so as to be openable and closable and on which the object to be measured can be placed. 15 and the lower end 1 of the support part 14
4a, and a support plate 16 having a peripheral wall portion 16a that fits loosely into the supporting plate 16, and a hole portion 16b for passing through the leg portion 12a of the first container 12 without contacting the support plate 16;
The leg portion 12a of the first container 12 is positioned and supported by a support recess 18 formed on the upper surface of the weighing device 17, and the total weight applied to the support tray 16 is transferred to the weighing device 17. It acts on the receiving part 19 of 17.
Note that 19a is a screw for attaching the support plate 16 to the receiving portion 19. 17a is an annular plate,
A hole for forming a support recess 18 is provided and attached to the top surface of the weighing device 17.

Referring to FIG. 3, the load applied to the receiving part 19 is converted into an electrical signal by the load cell 20, and the output thereof is subjected to various calculations by the measuring part 21 to measure and display the specific gravity. It is something. The measurement unit 21 includes an amplifier 22 that amplifies the output of the load cell 20 and outputs an analog signal according to the load;
An A-D converter 23 that converts an analog signal into a digital signal, a processing device 24 consisting of a microcomputer, a memory 25, a first key 26a, and a second key.
It consists of an input key section 26 having keys 26b, and a display section 27.

These configurations will be explained in more detail along with their functions. As shown in FIG. 2, there is water L in the first container 12.
By pressing the first key 26a without placing the object M on the lid 15 or inside the second container 13, the output of the load cell 20 at that time, that is, the output of the load cell 20 at that time, The weight A of the second container 13 is reset, and "0" is stored in the memory 25 and "0" is also displayed on the display section 27. At this time, the gravity acting on the second container 13 is
3 itself (support part 14, lid body 15, saucer 1
6 etc.) from the second container 13 by water L.
It is calculated by subtracting the buoyant force given to .

Next, by placing the object M to be measured on the lid 15, its air weight is measured and the display unit 2
7, but by pressing the second key 26b in this state, the air weight M1 is stored in the memory 25.
stored within. Next, the object to be measured M is placed in the second container 13 with the first lid 15 opened, and water
When the lid 15 is closed again, the underwater weight M2 of the object M is measured, and in parallel with this measurement, S=M1÷(M1-M2)... ...(1) is performed by the processing device 24, and the specific gravity S, which is the result of the calculation, is displayed on the display section 27.

Here, when the object M is lifted after measuring the weight in the air of the object M, the weight in the air becomes zero, but by detecting this, the display unit 2
7, the display of weight is automatically switched to the display of specific gravity S, and the fact that it is the display of weight or specific gravity is also displayed. The display section 27 also displays the value of the specific gravity S as well as the processing device 2.
The specific gravity table stored in the storage device in 4 and the unit price of each precious metal are referred to, and the quality of the object to be measured (for example, "K18"), the net weight of the precious metal, and the price are displayed. . In addition, in the present invention, the specific gravity does not necessarily have to be displayed on the display section 27, and the processing device 24
It is not necessary for the specific gravity to exist as a numerical value in the memory 25; the point is that it is sufficient that something substantially equivalent to the specific gravity is measured and the value of the object M to be measured is recognized.

According to the embodiment described above, the object to be measured M is placed in the lid body 15.
The device is placed on top to measure its weight in the air, and then placed in the second container 13 and submerged in water to measure its weight in the water.Therefore, there is no need for hanging items such as hooks as in the past. This eliminates errors and enables highly accurate measurements. Furthermore, the specific gravity of the object M can be measured by inserting the first key 26a or the second key 26b before and after placing the object M on the lid 15, and by putting the object M into the second container 13. Therefore, the specific gravity can be measured extremely easily and quickly. and,
Since the object M to be measured can be placed or placed in the second container 13 so as to be immersed in the water L, there is no need to prevent it from coming into contact with the container as in the conventional case.
The measurement work is easy, and the object M to be measured may have any shape as long as it can be placed on the lid 15 and can fit into the second container 13. In addition, when measuring a large number of objects in sequence, if you take out the previous object from the water L, the amount of water L will decrease slightly, but each time you make a measurement, press the first key 2.
6a to reset, this does not pose any problem to the measurement.

In the above embodiment, the specific gravity of the object to be measured M is determined by setting the specific gravity of the water L to 1, which is usually sufficient, but in order to obtain it more accurately, the temperature of the water L is measured and the specific gravity of the water L is determined. The specific gravity may be determined and multiplied by S determined by the above equation (1). Furthermore, when a liquid other than water is used, the specific gravity of the liquid may be multiplied in the same manner as described above.

In the embodiments described above, the memory 25 may be a storage device or a register within the processing device 24. The calculation for determining the specific gravity S can be performed in various ways, and can be performed by a suitably programmed microcomputer or by a hard logic circuit. In addition, if it is integrated with a substance other than the object to be measured, such as a platinum ring with a diamond attached, you can enter the weight or specific gravity value of the substance to determine the object to be measured. It is possible to determine the specific gravity of only To do so, press input key 2
6, it is recommended to use a numeric keypad or symbol keys to enter the type, specific gravity, or weight of the substance other than the object to be measured. You may also enter the type and current price. Load cell 20
Although a device using a semiconductor pressure sensitive element or a strain gauge, or other devices can be used as the device, it is desirable from the viewpoint of accuracy to use a device that causes as little displacement as possible due to changes in load. The second container 13 may be a mesh-like one, or it may be a regular non-net-like container with an appropriate number of holes provided at appropriate locations. It is sufficient if it can freely flow in and out of the container 13. Instead of the lid body 15,
A mounting section may be fixedly provided near the opening 13a. In addition, these first containers 12 and second containers 1
3, the support portion 14, and the support plate 1.
6. Various shapes can be adopted for the receiving portion 19. Second container 13 located near the water surface
By making the horizontal cross-sectional area of the portion 13b as small as possible, the change in the buoyancy of the second container 13 due to the change in the water surface when the object M is placed in the water L is so small that it can be ignored. , which is desirable from the point of view of accuracy.

Although the case where the object to be measured M is a precious metal has been described above, it can also be used to check the purity and authenticity of other substances such as jewelry, plastic, copper products, die-cast products, etc.

(Effect of the invention) According to the invention, after the object to be measured is placed on the aerial mounting section and its weight in the air is measured, the second container is placed so that the object to be measured is immersed into the liquid without being suspended. Since the device can be placed inside the device, there is no need for hanging items such as hooks as in the past, and highly accurate measurements can be performed without any errors caused by this. In addition, there is no need for hanging work as in the conventional method, there is no need to be careful not to come into contact with the container, and the shape of the object to be measured is rod-shaped.
Even if it is chain-shaped or coin-shaped, it can be easily measured. Since it is possible to perform measurements by simply operating the appropriate keys before and after placing the object to be measured on the aerial mounting section and then placing it into the second container, it is possible to determine the specific gravity extremely easily and quickly. can be measured. Therefore,
From the measured specific gravity, the value of the object to be measured can be quickly expressed in various ways.

In particular, according to the present invention, the second container is immersed in the liquid from the beginning, and in this state, the reference point (○ point) of the measuring device that supports it can be taken, so that the second container is submerged in the liquid. When measuring the weight, the buoyant force applied to the second container can be not measured, so that the buoyant force of the second container is almost ignored when measuring the weight in the air and the weight in the water of the object to be measured. This allows for more accurate weighing.

That is, according to the present invention, the aerial weight of the object to be measured is measured with the aerial mounting section supported by the second container while the second container is immersed in water, so that the underwater weight of the object to be measured can be measured. This is done under exactly the same conditions as in the case where the method is used, and therefore the specific gravity of even a small weight object such as a precious metal can be measured extremely accurately.

Further, according to the present invention, the second container for weighing the object to be measured is supported by the measuring device, and there is no need for the second container to move up and down, and for this reason, the liquid in the second container is shaken. Since there is no movement, the weight of the object to be measured in the air and underwater can be measured quickly and accurately.

[Brief explanation of the drawing]

1 to 3 show embodiments of the present invention,
FIG. 1 is an exploded perspective view of a specific gravity measuring device, FIG. 2 is a sectional front view of the specific gravity measuring device, FIG. 3 is a block diagram of the specific gravity measuring device, and FIG. 4 is a front view of a conventional specific gravity measuring device. L...Water (liquid), M...Object to be measured, 11...
Specific gravity measuring device, 12...first container, 13...second
Container, 15...Lid (aerial placement part), 17...Measuring device, 20...Load cell (sensor), 21
...Measurement unit, 24...Processing device, 26a...First
Key, 26b...Second key.

Claims (1)

[Scope of utility model registration request] A first container containing a liquid, a second container accommodated in the first container in a non-contact manner and into which the liquid in the first container can freely flow in and out; The measuring device includes an aerial mounting section for placing an object to be measured in order to measure the gravity inside the container, and a weighing device for receiving and supporting a second container.
A sensor that converts the weight acting on the container into an electrical signal, an output of the sensor when the object to be measured is placed on the aerial mounting section, and an output of the sensor when the object to be measured is placed submerged in the second container. A measuring unit that measures the specific gravity of the object to be measured based on the output of the sensor when the object is placed.