JPH0536180Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] This invention relates to a balance for measuring the weight of powder, liquid, etc.

[Conventional technology]

BACKGROUND OF THE INVENTION Conventionally, as a balance for weighing objects to be measured such as powders and liquids, a balance shown by reference numeral 1 in FIG. 6 has been known. Reference numeral 11 in the figure is a base. A support 12 is provided on this base 11, and a lever 13 is provided on this support 12. A weighing pan 14 for storing an object to be measured is provided at one end of the lever 18, and a weight 15 is provided at the other end. The weight of the weight 15 is set so that the lever 13 is balanced when a predetermined weight of the object to be measured is placed in the weighing pan 14. The balance 1 configured as described above adds the object to be measured little by little into the weighing pan 14, and when the weight of the object in the weighing pan 14 reaches a predetermined value, the weight of the object to be measured in the weighing pan 14 reaches a predetermined value. Then, the lever 13 is balanced and it can be seen that a predetermined weight of the object to be measured is stored in the weighing pan 14.

[Problem that this idea attempts to solve]

However, in the case of this balance 1, the mass of the lever 13 is large relative to the change in the weight of the object to be measured, so even if the weight of the object to be measured reaches a predetermined value, the lever 13 does not suddenly move. , its inclination angle changes gradually. Therefore, there is a problem in that it takes time to confirm or detect that the weight of the object to be measured in the weighing pan 14 has reached a predetermined value, resulting in a time lag. In particular, powder or liquid is continuously supplied to the weighing pan 14 by a feeding device or the like.
In the case of supplying the powder or liquid into the container, there was a problem in that due to the above-mentioned time lag, too much powder or liquid was filled, making it impossible to accurately weigh the powder or liquid.

[Purpose of invention]

The object of this invention is to provide a balance in which, when weighing an object with a lever, the lever rapidly tilts when the weight of the object reaches a predetermined value.

[Structure of the idea]

In order to achieve the above object, this invention includes a lever whose central portion is rotatably supported by a support body, a lever provided with its longitudinal direction aligned with the longitudinal direction of the lever, and a container whose both ends are positioned on both sides of the rotation center of the lever;
The container has a liquid stored in the container in an amount that is about half or less of the internal volume of the container.

〔Example〕

An embodiment of this invention will be described below with reference to FIGS. 1 to 5.

FIG. 1 shows a balance 2 according to this invention.

This balance 2 has a base 21. A wedge-shaped support 22 is provided at the center of the base 21.
is provided. A long plate-shaped lever 23 is placed on this support 22 . This lever 23
is supported at its center by the support body 22, and is arranged with its longitudinal direction aligned with the longitudinal direction of the base 21. A cylindrical fitting base 24 is provided on one end of the lever 23 . A cell 25 is placed on this fitting base 24 . This cell 25 is a cylindrical container for storing the powder to be weighed, and is connected to the fitting base 24.
It is removably fitted to the inner peripheral surface of. On the other hand, a weight 26 is mounted and fixed on the other end side of the lever 23. Moreover, a cylindrical container (container) 27 whose both ends are sealed is provided at the center of the lever 23 . This cylindrical container 27 is disposed with its axis directed in the longitudinal direction of the lever 23 and with both ends positioned at both ends with the support 22 in between. This cylindrical container 27 contains mercury (liquid) 28 sealed therein. The amount of mercury 28 in this cylindrical container 27 is smaller than the internal volume of the cylindrical container 27, and can be adjusted as appropriate depending on the weight to be weighed. And this mercury 28 is
Due to the slight inclination of the lever 23, the fluid flows from one end of the cylindrical container 27 to the other end, or from the other end to the one end. In addition, stoppers 29, 29 are provided below the lever 23 and on the upper surface of both ends of the base 21 so as to protrude upward. When the lever 23 is tilted at a certain angle or more, its lower surface abuts the upper end of the stopper 29, preventing it from tilting any further.

Next, we will discuss the action of the balance 2 as described above in the second section.
This will be explained with reference to Figures a and b.

First, as shown in Figure 2a, lever 2 of balance 2
3 is tilted so that the weight 26 side is located below the fitting base 24 side. In this state,
Mercury 28 in the cylindrical container 27 is located on the weight 26 side. From this state, the powder to be weighed is dropped into the cell 25 and gradually filled.
When the weight of the powder stored in the cell 25 reaches a predetermined value, the lever 23 gradually begins to move in the direction in which the cell 25 descends. Then, the mercury 28 in the cylindrical container 27 moves slightly toward the cell 25 side. As a result, the center of gravity of the mercury 28 moves toward the cell 25, and the lever 23 further tilts in the direction in which the cell 25 side descends. In this way, the inclination of the lever 23 and the movement of the mercury 28 occur continuously, and the lever 23
The cell 25 rapidly tilts in the downward direction, resulting in the state shown in FIG. 2b.

As mentioned above, for this balance 2, lever 2
Since the cylindrical container 27 containing the mercury 28 is provided in the center of the cell 3, the lever 23 suddenly tilts when the weight of the powder filled into the cell 25 reaches a predetermined value. Therefore, it is possible to quickly confirm or detect that the weight of the powder has reached a predetermined value, and the accuracy of weighing can be improved. In particular, mercury 2
8 has a large specific gravity, even a slight movement of its center of gravity will cause a large moment to be applied to the lever 23, making it possible to tilt the lever 23 more rapidly. Further, since the mercury 28 has a large surface tension, it tends to move as a liquid within the cylindrical container 27 in a lump. For this reason, mercury2
8 rapidly moves toward the cell 25 as a whole once it starts moving, and therefore the lever 23 can be tilted rapidly. Furthermore, mercury 28
Since it has a large surface tension, it does not remain wet on the inner wall surface of the cylindrical container 27. Therefore, the weight distribution inside the cylindrical container 27 does not vary depending on the amount of mercury remaining on the inner wall surface of the cylindrical container 27, and therefore, the weighing accuracy can be improved.

In the above embodiment, mercury is used as the liquid sealed in the cylindrical container 27, but it is not limited to this, and water, alcohol, etc. may also be used.
In short, it only needs to be liquid. Further, in the above embodiment, the cylindrical container 27 whose both ends are closed is used as a container.
However, there is no need to be limited to this; for example, a container with an open top may be used, and any shape of container may be used as long as it can store liquid.
Furthermore, in the above embodiment, the cylindrical container 27
are arranged in the center of the lever 23 with both ends thereof being positioned symmetrically on both sides of the lever 23 with the support body 22 in between, but there is no need to limit it to this; You can leave it there.

Next, a description will be given of a filling device 3 that weighs and fills a certain amount of powder into a cell 25 using the above-mentioned balance 2.

This filling device 3 includes a table 31, on which the balance 2 is placed.

On the other hand, a photoelectric switch 32 is provided on the table 31 near one end of the lever 23. This photoelectric switch 32 is designed to be able to detect the inclination of the lever 23. Further, on the table 31, an air cylinder 33 is placed and fixed on the other end side of the base 21.
The tip of the piston rod of the air cylinder 33 is connected to the other end of the base 21, so that the base 21 and the lever 23 placed thereon can be moved in the longitudinal direction.

On the other hand, above the fitting table 24, a gutter 34 provided in the vibrating feeder is provided. This gutter 34 has a U-shaped cross section and is arranged approximately at right angles to the longitudinal direction of the lever 23.
It is provided so as to be inclined from one end side to the other end side. A hole 34a is provided in the bottom plate of the gutter 34 above the fitting base 24. And gutter 34
Powder flowing inside from above falls into the cell 25 placed on the fitting base 24 through the hole 34a. Further, the powder that has not fallen from the hole 34a is stored in a storage bottle 35 provided below the lower end of the gutter 34.

Further, a guide plate 36 is provided on the bottom plate of the gutter 34 where the hole 34a is provided. This guide plate 36 is pivoted on the inner surface of the side wall of the gutter 34 in a state perpendicular to the bottom plate of the gutter 34. Further, an air cylinder 37 is provided on the side wall of the gutter 34 on the side opposite to the guide plate 36.
This air cylinder 37 is arranged with its axis oriented substantially perpendicular to the gutter 34, and the tip of its piston rod is connected to the guide plate 36. By protruding the piston rod, the air cylinder 37
As shown in Figure b, the guide plate 36 is inserted into the hole 34.
The hole 34a protrudes upstream from the hole 34a to prevent powder from flowing into the hole 34a. Furthermore, by retracting its piston rod, the air cylinder 37 draws the guide plate 36 toward the inner surface of the side wall of the gutter 34, as shown in FIG. 4a, and the powder can flow into the hole 34a. It is becoming more and more like this.

Next, the operation of the filling device 3 as described above will be explained with reference to FIG. 5. FIGS. 5a to 5d illustrate the step-by-step process of weighing and filling powder using the filling device 3. The operation of the filling device 3 described below is automatically operated by a control device (not shown).

FIG. 5a is a diagram showing a state in which the lever 23 is arranged so that the fitting base 24 is shifted from directly below the gutter 34. In this state, the cell 25 is fitted and placed on the fitting table 24.

Next, the air cylinder 33 is actuated, and as shown in FIG.
The lever 23 is moved so that the cell 25 is located below the hole 34a of the gutter 34, as shown in FIG. The lever 2 is then reset by a reset device (not shown).
The lever 23 is tilted so that the weight 26 side of No. 3 is located below the fitting base 24 side, and the cylindrical container 27
Place the mercury 28 inside toward the weight 26 side.

In this state, the powder is flowed from the upper part of the gutter 34, and the air cylinder 37 is operated to position the guide plate 36 at the position shown in FIG. 4a.
Then, the powder flowing through the gutter 34 falls downward from the hole 34a and is stored in the cell 25. In this way, when the weight of the powder stored in the cell 25 reaches a predetermined value, the lever 23 moves as described above.
The cell 25 tilts rapidly in the downward direction, and as shown in FIG.
The situation will be as shown below.

On the other hand, in the state shown in FIG. 5b, that is, in a state where the cell 25 side of the lever 23 is higher than the weight 26 side, the end of the lever 23 on the cell 25 side is located just in front of the photoelectric switch 32. After that, the weight of the powder in the cell 25 reaches a certain value, and the lever 23
When the end of the cell 25 side suddenly moves downward,
A photoelectric switch 32 detects this and sends a signal to a control device (not shown). Based on this signal, a control device (not shown) sends a signal to the air cylinder 37 to cause the piston rod of the air cylinder 37 to protrude. As a result, the guide plate 36 of the gutter 34 is located above the hole 34a, as shown in FIG.
The liquid flows downward without entering a and is stored in the storage bottle 35. In this way, the supply of powder to the cell 25 is stopped.

When a predetermined weight of powder is stored in the cell 25 as described above, the air cylinder 33 is operated and the lever 23 is moved toward the air cylinder 33 as shown in FIG. 5d. Then, the cell 25 filled with powder is taken out.

As mentioned above, this filling device 3 includes a balance 2 whose lever 23 rapidly tilts when the filling weight of powder reaches a predetermined value, a photoelectric switch 32 which detects the tilt of this balance 2, and a photoelectric switch 32 that detects the tilt of this balance 2. Photoelectric switch 32
An air cylinder 37 and a guide plate 36 that receive a signal from the air cylinder and stop the powder from falling, and this filling device 3
Since it has a control device that controls the whole, when the weight of the powder filled into the cell 25 reaches a predetermined value, the lever 23 is suddenly tilted, thereby quickly supplying the powder to the cell 25. can be stopped. In this way, the response from when the predetermined weight is reached until the supply of powder is stopped is quick, so there is no need to supply too much powder, and the powder can be weighed with the desired accuracy (accuracy of about 1/100g). can be done. Further, since the filling and weighing of powder into the cell 25 can be performed automatically, it is possible to reduce labor costs and shorten working time. Furthermore, since the above-mentioned filling device 3 has a simple structure, the cost can be kept low compared to a case where an expensive electronic balance is combined with a control device and a powder supply device.

[Effect of idea]

As explained above, according to this invention, a lever is supported at its center by a support so as to be freely rotatable, a container is provided on the lever with its longitudinal direction aligned with the longitudinal direction of the lever and both ends are positioned on either side of the pivot center of the lever,
Since the container is provided with a liquid stored in an amount of approximately half or less of its internal volume, when the substance to be measured is filled, the liquid moves gradually until the amount of the substance to be measured reaches a predetermined amount, and then, after the amount of the substance to be measured reaches the predetermined amount, the liquid flows into the side filled with the substance to be measured all at once.

As a result, the lever gradually rotates during filling, and when the filling amount reaches a predetermined amount, the lever is rotated rapidly, thereby quickly determining or detecting quantitative filling. In addition, it is possible to improve the accuracy of weighing.

Moreover, since the liquid has viscosity and the free surface of the liquid is almost maintained during the rotation of the lever, the movement from the initial rotation of the lever to the object to be measured is performed smoothly. The impact force with the container can be small.

As a result, the load acting on the lever support portion of the support can be reduced, and the durability of the support can be improved.

[Brief explanation of the drawing]

Fig. 1 is a front view showing a balance which is an embodiment of the invention, Fig. 2 is a front view showing the operation of the balance according to the invention, and Fig. 3 is a front view showing a filling device which is an embodiment of the invention. A perspective view, FIG. 4 is a plan view showing the action of the gutter of the filling device, FIG. 5 is a front view showing the action of the filling device in order, and FIG. 6 is a front view showing an example of a conventional balance. FIG. 7 is a front view showing a state in which the levers are balanced in a conventional balance. 2... Balance, 22... Support, 23... Lever,
27... Cylindrical container (container), 28... Mercury (liquid).

Claims (1)

[Scope of utility model registration request] A lever whose central portion is rotatably supported by a support body, the longitudinal direction of which is provided along the longitudinal direction of the lever, and whose both ends sandwich the center of rotation of the lever. A balance comprising a container located on both sides, and a liquid stored in the container with an amount less than about half of its internal volume.