JPH0112196Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a soil physical property measuring instrument whose purpose is to measure the physical properties of soil whose physical properties are complex.

Soil is a substance with a granular structure, but it is divided into three phases: a solid phase, a liquid phase, and a gas phase. Its physical properties are complex, and there are various conventional devices for measuring this. However, it was extremely inconvenient as it required a lot of effort to perform calculations after reading the measured values.

In view of these conventional drawbacks, the present invention is characterized by measuring the actual volume of a soil sample placed in a certain container by compressing it at a certain pressure, and directly reading the volume with a dial gauge.

To explain the embodiment of the present invention with reference to the drawings, an air cylinder 2 for compressing air is installed inside the housing 1.
A connecting plate 4 is used at one end of a rod 3 protruding from the front of the cylinder, and a rack 5 is attached parallel to the rod. Reference numeral 6 denotes a large-diameter first gear mounted on a shaft 8 which is supported on a gear block (not shown) fixed to the housing 1.A second gear 7, which forms part of the gear block, is mounted on the shaft 8. be. 11 is a disc having a handle 10 on an eccentric part of the front surface, and the gear 6 is meshed with a toothed part 12a provided on a shaft rod 12 pivotally attached to this disc. Furthermore, a spindle 31 that interlocks with the long and short hands of a dial gauge 13 with a direct-reading reverse scale, which will be described later, is abutted on the connecting plate 4, and by operating this spindle, the long and short hands of the dial gauge are operated. It is something.

Reference numeral 20 denotes a sample chamber which is attached to the flat surface of the housing 1 and has a certain internal capacity.A lid 21 is attached to the upper part of the sample chamber 20 so as to be openable and closable. 22 is a Bourdon tube pressure gauge, 13 is a dial gauge with a reverse scale, and the scale is displayed in ml as the unit of volume.

A reverse scale 16 for marking the 1's digit is provided on the outer peripheral edge of the annular scale plate 15, and black numbers 17 from "0" to "4" are attached, and then inside the numbers 17,
A different color from the number 17, for example "5" in red
Numbers 18 up to "9" are attached. Furthermore, on the inner circumferential edge of the scale plate 15, "0" to "+" digits are marked.
Reverse scales 19 in increments of 10 up to "100" are provided at regular intervals. In addition, each half in the direction from the middle part of the number in the direction where the number increases is made into a red zone 19a,
Also, each half in the direction where the number decreases is a white part 19b.
It is divided into Furthermore, the rear part of the cylinder 2, the sample chamber 20, the pressure gauge 22, and the switching valve 24 for opening to the atmosphere.
are connected by a hard tube 25. 26 is a power input switch, and 27 is a pilot lamp.

Next, to explain how to measure a sample using this device, first, open the switching valve 24 and open the handle 1.
When rotating 0 counterclockwise, dial gauge 1
3, the long hand 14a and the short hand 14b are connected to the shaft 12.
is rotated counterclockwise by , and moved in the direction of "100" in FIG. And Rod 3 is the first
When the rod 3 is moved all the way to the left in the figure, the rod 3 connects to the micro switch 30 attached to the housing 1 and turns it on, turning on the pilot lamp 27. That is, by lighting the pilot lamp 27, it can be confirmed that the tip of the rod 3 is located at the fixed position before measurement, thereby preventing errors in the measured values. In this case, the pressure gauge 22 indicates the atmospheric pressure at the point where the device is located.

Next, after storing a sample for measurement in the sample chamber 20, the lid 21 is sealed, and then the switching valve 24 is switched to shut off the inside of the pipe from the atmosphere. Then the constant pressure created by compressing cylinder 2
P ₂ (from the formula below) is connected to the sample chamber 20 and pressure gauge 2.
Add to 2. This pressure gauge is equipped with a movable pressure setting needle so that the measurer can determine the position at which the pressure gauge needle should be stopped. That is, while watching the movement of the needle of the pressure gauge 22, rotate the handle 10 clockwise so that a pressure of P ₂ - P ₁ Kg is applied, and the needle of the pressure gauge is adjusted to the scale corresponding to the amount of P ₂ Kg pressurized. The air in the cylinder 2 is compressed until it indicates , and the handle 10 is pressed until the pointer of the pressure gauge matches the scale corresponding to the current atmospheric pressure plus the pressure of P ₂ - P ₁ kg.
Rotate clockwise and stop. By rotating this handle 10, the spindle 31 of the dial gauge 13 is moved to the right in FIG. hand,
Indicate the scale corresponding to the pressure. The volume of the sample contained in the sample chamber 20 is measured by reading this scale.

In other words, P ₂ - P ₁ Kg/cm ² is determined by the position of the pressure gauge pointer when the pointer of the dial gauge 13 matches the same value as the volume of a test piece (not shown). do. This is calculated based on the schematic diagram in Figure 2, and according to Boyle's law,
The pressure before piston compression is P ₁ (Kg/cm ² ), and the volume is V ₁
(ml), pressure after compression is P ₂ (Kg/cm ² ), volume is V ₂
(ml), then the formula P ₁ V ₁ = P ₂ V ₂ ... is established.

From the figure, if the radius of the cylinder is r (cm) and the compression stroke of the piston is l ₁ (cm), then V ₂ =V ₁ −πr ² l ₁ ... is established.

Now, by substituting the expression into the equation, P ₁ V ₁ = P ₂ (V ₁ −πr ² l ₁ ) (p ₂ −V ₁ )V ₁ = P ₂ πr ² l ₁ ∴V ₁ = P ₂ /P ₂ −P ₁ πr ² l ₁ ...Furthermore, a sample Vx (ml) is placed in the sample chamber and compressed with a piston until the pressure in the cylinder, sample chamber, etc. reaches P ₂ [Kg/cm ² ]. The stroke at this time is l ₁
−l ₂ (cm), then substitute (V ₁ −Vx) for V ₁ and (l ₁ −l ₂ ) for l ₁ , and from the equation, P ₁ (V ₁ −Vx)=P ₂ { (V ₁ −Vx) −πr ² (l ₁ −l ₂ )} (P ₂ −P ₁ )Vx＝(P ₂ −P ₁ )V ₁ −P ₂ πr ² l ₁ +P ₂ πr ² l ₂ ∴Vx =V ₁ −P ₂ /P ₂ −P ₁・πr ² l ₁ +P ₂ /P ₂ −P ₁・πr ² l ₂ ... Substitute the above formula into this equation and get Vx=P ₂ /P ₂ −P ₁・πr ² l ₂ ... From the above, the volume of the sample is 0 in the measuring instrument.
The distance ₂ l (cm) from the position x of the piston when a sample of (ml) is loaded and compressed to the y point when a sample of Vx (ml) is loaded is calculated as the cross-sectional area of the cylinder πr ² (cm ₂ )
It can be found by multiplying by P ₂ /P ₂ - _{P 1} .

Furthermore, in order to directly read this volume, set P ₂ /P ₂ −P ₁・r ² = α and set α per 1 mm of the dial gauge to an integer value that is easy to read directly, then P ₂ is =
It becomes P ₁ /α−πr ² . In reality, we use a test piece to find the pressure value of P ₂ , which is αml per 1mm.
Next, determine the starting point of the piston where the scale of the dial gauge and the volume value of the test piece match.

Next, to explain the reverse scale of the dial gauge, as shown in FIG. 4, the long hand 14a indicates "8" between "0" and "1" and "5" and "6". The hour hand 14b is located in the upper half of "10". When the short hand 14b is positioned in the upper half direction 19a of the reverse scale 19 in this way, the long hand 14a indicates the numbers 18 from "5" to "9", and the short hand 14b points below each number. half direction 19
b, the long hand 14a is "0" -
The number 17 up to "4" is indicated. Therefore,
Figure 4 shows "15.8", and Figure 5 shows "11.5".

As described above, the present invention allows the volume of the sample contained in the sample chamber to be directly displayed on the dial gauge simply by operating the handle, so there is no need for the measurer to make any calculations, making measurement easier.
Furthermore, in order to prevent erroneous readings on dial gauges with reverse scales, it is possible to indicate which number to read, depending on the position of the hour hand. It is possible to measure gender. Furthermore, since the measured value can be directly read without any conversion, it also has the advantage that errors in the measured value are relatively less likely to occur.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; Fig. 1 is a partially cutaway plan view, Fig. 2 is an explanatory drawing showing the relationship between the piston and cylinder, and Fig. 3 is a diagram showing the scale plate of a dial gauge. The plan view and FIGS. 4 and 5 are plan views of the dial gauge, respectively. 1...Housing, 2...Air cylinder, 3
... Rod, 4 ... Connection plate, 5 ... Rack, 6,
7... Gear, 12... Shaft rod, 13... Dial gauge, 20... Sample chamber, 23... Pressure gauge, 24...
...Switching valve, 30...Micro switch, 35...
spindle.

Claims (1)

[Scope of utility model registration request] One end of the rod 3 protruding from the air cylinder 2 and the rack 5 located parallel to the rod are fixed by a connecting plate 4, and the micro switch 30 attached to the housing 1 and the tip of the rod 3 are brought into contact with and separated from each other. A blinking pilot lamp 27 is attached to the housing 1, and numbers 17 from "0" to "4" are placed at regular intervals on the outer periphery of the annular scale plate 15 inside the first scale 16 formed for the minute hand. counterclockwise, and further inside the number is "5".
- Numbers 18 up to "9" are provided in the same counterclockwise direction, and "0" is provided on the inner periphery of the scale plate for the hour hand.
- A second scale 19 with numbers in increments of 10 up to "100" is formed in a counterclockwise direction, and each half of the scale in the direction of increasing numbers from the middle part between adjacent numbers is a red zone 19a, and as the numbers decrease, Engage the tip of a spindle 31 interlocked with the long hand 14a and short hand 14b supported by the central axis of the dial gauge 13, each half of which is divided into white parts 19b, into the connecting plate 4,
A soil physical properties measurement container consisting of a cylinder 2, a sample chamber that can be opened and closed and has a constant internal volume, a pressure gauge, and a switching valve for communicating with the atmosphere using a tube.