JPS5929209Y2 - Automatic water measurement device - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a device that measures the amount of water in a container to be measured as a change in water level displacement.

Conventionally, for example, when performing a soil test by placing a soil sample that has absorbed water into the elastic sleeve of a pressure vessel that is controlled to a constant pressure and applying pressure to it, the applied pressure causes the soil sample to move into the elastic sleeve of the pressure vessel. Water is drained into the connected fixed container, or depending on the soil type, the main pore space expands and the water in the fixed container is absorbed into the sample area.In other words, when pressure is applied to the sample, depending on the soil type, The changing amount of water can be measured by using a light source and a photoelectric element to detect the water level in a fixed container when no pressure is applied to the sample and when pressure is applied, that is, the set water level, and when the water level increases or decreases from this level. The motor is rotated in reverse to move the light source and the photoelectric element up and down until each set water level is detected, and the change in water amount is measured by the amount of vertical movement.

However, such conventional devices have the disadvantage that dust adhesion to the light source, photoelectric element, or fixed container, or dust contamination with the water in the fixed container interferes with water level detection, making it impossible to measure changes in water volume.

The present invention aims to improve the above-mentioned drawbacks, and one embodiment thereof will be described below with reference to the drawings.

The drawing shows a case where changes in water volume are measured in a soil test, 1 is a container to be measured in which changes in water volume are to be measured, and in this case, the pressure is controlled to a constant pressure by a pressure control device 2,
This is a pressure vessel in which a soil sample 4 that has absorbed water is inserted into an elastic sleeve 3.

Reference numerals 5 and 6 designate a three-contact type water level detector and a vertically movable container that communicate with the elastic sleeve 3 of the pressure vessel 1, respectively.

Reference numeral 7 designates a rotational-linear motion conversion mechanism, which is fixed to, for example, the vertical motion container 6, and is comprised of a female screw 7a and a male screw shaft 7b screwed into the female screw 7a.

Reference numeral 8 denotes a DC motor that stops and moves the vertically moving container 6 up and down via this mechanism 7.

5a to 5c are three contacts of the water level detector 5, and 9 determines the water level state based on the open/closed state of these three contacts 5a to 5c,
The water level is the set water level (contacts 5a and 5b are closed, contact sb
, 5c is open), and when the water level has increased above the set level (contact 58
5C is closed) and when the water level decreases below the set level (when contacts 53 to 5C are open), outputs a stop signal to stop the motor 8, a reverse rotation signal to rotate it in the reverse direction, and a forward rotation signal to rotate it forward, respectively. This is a state determination circuit.

This state determination circuit 9 is set to "O" when the contacts 5a to 5c are closed, for example.

210? 1. When contacts 5a and 5b are closed and 5b and 5c are open, "O", "1', and when contacts 5a to 5c are open, it is 1"
Two comparators 9a that serve as the output of u 111
1 s 9 b 1, a NAND circuit 9a2 which receives these outputs as input, and both comparators 9a1゜9b,
It consists of a series circuit of an exclusive OR circuit 9b2 and a NOT circuit 9b2, which receive the output of .

10 is a control circuit for the motor 8 connected to the state determination circuit 9, and is used to stop the motor 8 and rotate it in forward and reverse directions.

11 is a potentiometer connected to the male threaded shaft 7b of the rotary-linear conversion mechanism 7, and 12 is an amplifier for amplifying the output of the potentiometer 11.

In the above configuration, the water level of the water level detector 5 and the vertical motion container 6 when the pressure F is not applied to the sample 4 is set as the set water level.

At this time, the open/close states of the contacts 5a to 5c of the water level detector 5 are as shown in the figure: contacts 5a, 5t) are closed, and contacts 5b, 5c are closed.
is in the open state.

In this state, is the output of comparator 9a1-9b1? lQTT.

11171, and the output of the NAND circuit 9a2 is
However, since the output of the exclusive OR circuit 9b2 is 1" and the output of the NOT circuit 9b3 is "0", the control circuit 10 becomes an open circuit and the motor 8 is in a stopped state.

Now, if pressure F is applied to sample 4, sample 4 will change depending on the soil quality.
Water is drained from the area toward the water level detector 5 and the vertical motion container 6, or conversely, water is absorbed into the sample 4 area.

The water level of the water level detector 5 decreases or increases due to this suction and water, thereby causing the contacts 5a to 5c to open or close.

When the water level decreases below the set water level and contacts 5a to 5c open,
The outputs of comparators 9a1 and 9b1 are! l M, 1″
Therefore, the output of the NAND circuit 9a2 becomes "Ou", the output of the exclusive 1A circuit 9b2 becomes "O", and the output of the NOT circuit 9b3 becomes "1".

Further, when the water level increases above the set water level and the contacts 5a to 5c close, the comparators 9a, 9b.

The output of ``Q?1, II Q +1'' becomes ``1'', the output of NAND circuit 9a2 becomes ``1'', the output of exclusive OR circuit 9b2 becomes ``On'', and the output of NOT circuit 9b3 becomes ``1''. Become.

In either case, the output of the NOT circuit 9b3 becomes "1", so the control circuit 10 becomes a closed circuit, and the NAND circuit 9a2
The outputs "0" and "1" actuate the forward and reverse rotation circuits of the control circuit 1o, respectively, to rotate the motor 8 in the forward and reverse directions. be moved up or down.

As a result, the water in the container 6 is sent to the water level detector 6, or conversely, the water in the detector 6 is sent to the container 6, and the water level is controlled to the set water level, as well as the amount of upward movement or downward movement of the vertical movement container 6. Alternatively, the amount of water absorbed or discharged, that is, the change in the amount of water, can be measured by the amount of forward rotation or reverse rotation of the motor.

For example, changes in the amount of water can be directly read from the water amount scale attached to the vertical movement container 6, and can also be known from the electrical output obtained through the amplifier 12 from the potentiometer 11 connected to the male screw 7b as shown.

In addition, although the example describes the case where the amount of absorbed water is measured in the test of the soil sample, the present invention can be generally applied to the case where changes in the amount of water are measured.

As described above, since the present invention uses a contact type water level detector, water level detection malfunctions may occur due to dust adhesion or contamination, unlike devices configured using conventional photoelectric water level detectors. , and there is no risk of malfunction, and changes in water volume can be reliably measured based on the amount of vertical movement of the vertically movable container and the amount of forward and reverse rotation of the motor, and when changes in water volume are output electrically using potentiometers, etc. as in the example, Not only does data processing become easier, but by changing the installation position of the contact type water level detector in the vertical direction, the water level setting and water volume setting can be changed, and the water level status can be changed by changing the open/closed state of the contact. A state determination circuit that outputs a stop signal and a forward/reverse rotation signal enables the motor to stop and rotate forward/reverse quickly and reliably, making measurement operations smoother and preventing water volume changes. While the water level is being measured, the water level is automatically returned to the set water level, so it is particularly effective in measuring changes in the amount of water relative to the set water level, and it is also possible to measure the number of changes.

BRIEF DESCRIPTION OF THE DRAWINGS The drawing is a configuration explanatory diagram showing one embodiment of the device of the present invention. 1... Container to be measured, 5... Contact type water level detector, 5a to 5c... Contact, 6...
Vertical movement container, 8...motor, 9...state determination circuit, 10...control circuit for motor 8.

Claims (1)

[Scope of utility model registration request] A contact type water level detector that detects the water level when the amount of water in the container to be measured is a set amount of water and when it has increased or decreased from the set amount of water, for a container to be measured in which a change in water amount is to be measured;
The vertical movement container, which is stopped and moved up and down by stopping and forward/reversing the motor, is connected to the water level detector, which determines the set water level and the state of the water level when it increases or decreases from the set water level by the open/closed state of the contact. The water volume is characterized by being connected to a state determination circuit that outputs a stop signal that stops the motor and a check rotation signal that causes reverse IE rotation to the motor control circuit when the water level reaches a set level and when the water level increases or decreases from the set water level, respectively. Automatic measuring device.