JP2552888Y2 - Probe rod insertion device for soil thermal resistance measurement - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a probe rod insertion device for measuring soil thermal resistance for measuring the thermal resistance of soil, for example, when an electric power cable or the like is buried underground.

[0002]

2. Description of the Related Art For example, when burying a power cable or the like underground, it is necessary to consider the heat resistance of the covering of the cable, and therefore, it is necessary to determine the allowable current of the power cable. In such a case, the thermal resistance of the soil, which is related to the allowable current of the cable, is measured.

Conventionally, to measure the thermal resistance of soil, a probe bar equipped with a heat source and a thermocouple is inserted into the soil, and radiant heat from the heat source in the probe bar is passed through the soil by a thermocouple. A method of measuring the temperature and calculating the temperature gradient from the temperature change to obtain the thermal resistance has been used. At this time, in order to insert the probe bar for measuring the soil thermal resistance into the soil, a guide bar having the same diameter as the probe bar is previously driven into the soil with a hammer into a required length, and then,
After the guide bar is pulled out, a probe bar is similarly driven into the formed hole with a hammer.

[0004]

[Problem to be solved by the invention] However,
If the soil is hard, for example, when the probe is driven into the probe with a hammer, the probe is repeatedly subjected to an impact load, which causes the internal thermocouple to separate and the probe itself to bend, causing In some cases, it was difficult to reuse the needle bar. The probe bar is cumbersome to manufacture and therefore expensive, and if not reusable, the cost for the measurement is high and undesirable.

Accordingly, an object of the present invention is to enable the probe bar to be inserted into the soil without applying an impact load to the probe bar, avoiding damage to the probe bar, enabling reuse, and enabling soil re-use. It is an object of the present invention to provide a probe insertion device for measuring soil thermal resistance which can reduce the cost for measuring the thermal resistance of the soil.

[0006]

The above object is achieved by the probe rod insertion device for measuring soil thermal resistance according to the present invention. In summary, the present invention provides a clamp means for detachably holding a probe bar equipped with a heat source and a thermocouple for measuring soil thermal resistance, and a driving press for vertically moving the clamp means. Means, a base attached to the drive pressing means, temporarily fixed to the ground with a temporary anchor, the clamp means, a pair of clamp members for gripping the probe bar,
A toggle clamp mechanism that enables the pair of clamp members to be brought into and out of contact with each other, wherein the drive pressing unit includes a hydraulic cylinder connected to one of the pair of clamp members via a connecting member. This is a probe rod insertion device for measuring soil thermal resistance.

[0007]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective view of a probe rod insertion device for measuring soil thermal resistance according to the present invention. Referring to FIG. 1, in the present embodiment, the probe insertion device for measuring soil thermal resistance according to the present invention includes a plate-like base 1, and a guide hole for inserting the probe bar in the center of the base 1. 13 are provided.
Further, the base 1 is provided with driving and pressing means, that is, hydraulic cylinders 2 and 2 in this embodiment, which are located on the left and right of the guide hole 13, and the piston rods 2 </ b> A and 2 </ b> A can move up and down at the top. Extends. Piston rod 2A, 2A
One end of each of the connecting members 3 and 3 extending laterally is fixed, and clamp means 4 are provided at the other ends of the connecting members 3 and 3 so as to face each other.

As shown in detail in FIG. 2, the clamp means 4 includes clamp members 4C and 4D having semicircular grips 4A and 4B, and a conventionally known toggle clamp mechanism 6,6. And can be separated from each other.
Further, a semi-cylindrical elastic support, for example, neoprene rubber 5, 5 or the like is adhered to the inside of the semicircle of the gripping portions 4A, 4B, and the tip is operated by operating the toggle clamp mechanisms 6, 6. The body of the rod 12 can be firmly grasped from the left and right.

In this embodiment, the clamp member 4D is integrally fixed to the end of one connecting member 3, but the clamp member 4C is slidably fitted to the other connecting member 3. Thus, the clamp operation of the probe bar 12 by the toggle clamp mechanisms 6, 6 is facilitated.

The hydraulic cylinders 2 and 2 have connecting hoses 8 and
A branch box 11 is connected to the hydraulic cylinders 2 and 2 via a control valve 9 to distribute hydraulic oil supplied from a hydraulic source (not shown) via a supply hose 10 to the hydraulic cylinders 2 and 2. .

The operation of the probe insertion device for measuring soil thermal resistance according to the present invention having the above structure will be described. First, the base 1 is placed on the ground to be measured, and temporarily fixed to the ground by the temporary anchor 7. I do.

Then, the probe clamp 12 is gripped and fixed by the clamp means 4 by operating the toggle clamp mechanisms 6 and 6.
Next, pressurized oil is supplied to the hydraulic cylinders 2 and 2, and the adjusting valve 9 is operated to lower the piston rods 2A and 2A, thereby forcing the probe bar 12 into the soil.

Therefore, according to the device of the present invention, the probe bar 1
The probe bar 12 can be inserted into the soil without an impact load being applied to the probe 2. Therefore, the probe can be used repeatedly without causing the thermocouple inside the probe bar to peel off and without causing the probe bar 12 to bend. Further, a pair of clamp members 4C,
By including the 4D and the toggle clamp mechanism 6 that allows the clamp members 4C and 4D to come and go, the body of the probe bar 12 can be firmly and quickly gripped from the left and right, and can be operated on site. The properties are good.

As a practical matter, the following calculation is made for the adjustment of the pressure oil. That is, the allowable ground bearing capacity of the ground is 1.
Assuming that the probe bar 12 is 3 to 2.6 kg / cm ² (hard ground) and the diameter of the probe bar 12 is 20 mm, the sectional area (A) is A = 3.14.
cm ² , and the probe bar 12 can be pushed into the soil with a force higher than the earth bearing force. Therefore, if, for example, 5 kg / cm ² is applied to the probe bar 12, the insertion pressure (P) is P =
3.14 x 5１４16 kg.

Therefore, the pressure of the hydraulic cylinders 2, 2 is
For example, if the tongue is set to 10 tons, the tightening force of the toggle clamp mechanisms 6, 6 is 240 kg / cm ² , and the coefficient of friction between the elastic support 5 and the probe bar 12 is 0.3 to 0.5, the clamp 4 is gripped. Force (F) is F = (0.3-0.5) × 24
0 = 72 kg to 120 kg, which is much larger than 16 kg, and the device of the present invention can operate very effectively.

Although the hydraulic cylinders 2 and 2 are used as the driving and pressing means for pressing the probe bar 12 in the above embodiment, a driving and pressing means using a screw mechanism such as a panda jackie may be employed. .

[0017]

As described in detail above, the probe bar insertion device for measuring soil thermal resistance according to the present invention inserts a probe bar equipped with a heat source and a thermocouple into the soil to heat the soil. When measuring the resistance, the probe bar is detachably gripped by the clamp means, and a hydraulic press or a drive pressing means provided with a screw mechanism for vertically moving the clamp means is provided on the base. Is designed to be fixed to the ground via a temporary anchor, so that it can be inserted into the soil without impact load on the probe bar, thus avoiding damage to the probe bar and reducing reuse. This has the effect of making it possible to reduce the measurement cost, and is practically useful. In addition, by providing a pair of clamp members and a toggle clamp mechanism that allows the clamp members to come and go as the clamp means,
The body of the probe bar can be firmly and quickly gripped from the left and right, and the operability on site is good.

[Brief description of the drawings]

FIG. 1 is a perspective view of a probe bar insertion device for measuring soil thermal resistance according to the present invention.

FIG. 2 is a detailed perspective view of a clamping means.

[Explanation of symbols]

 Reference Signs List 1 base 2 hydraulic cylinder (drive pressing means) 2A piston rod 4 clamping means 6 toggle clamp mechanism

Claims (1)

(57) [Scope of request for utility model registration] 1. Clamping means for detachably holding a probe bar equipped with a heat source and a thermocouple for measuring soil thermal resistance therein, and drive pressing means for vertically moving said clamp means. , attached to the drive pressing means, and a base on which is temporarily fixed to the ground at the temporary anchor, the clamp
The means comprises a pair of clamp members for gripping the probe bar,
Toggle clamp that allows the pair of clamp members to be connected and separated
A driving mechanism, wherein the driving and pressing means is
The hydraulic system connected to one of the pair of clamp members
A probe rod insertion device for measuring soil thermal resistance, comprising a cylinder.