JPS6266148A - Soil water content detecting element - Google Patents

Abstract

PURPOSE:To detect the water content by decreasing an error by a soil temperature, by providing temperature and humidity detecting elements in the vicinity of an opening part of a cylindrical case whose tip has an acute angle, and which has an opening, and a lead leading-out port on the lower side face, and the upper side face, respectively. CONSTITUTION:The upper and the lower parts of a case 5 are joined by a screw part 6, and a supporting base 4 is fixed to a joint part. On the lower side face of the case 5, a network window 7 by a water repellent material is provided so as to be opposed to a temperature detecting element 1 and a humidity detecting element 2, and a distance from the center of the window is graduated 10. The case 5 is erected vertically on the ground and a head 9 is hit with a hammer, and the detecting elements 1, 2 are made to reach a prescribed part by using the scale 10 as a reference. After soil and a detecting element have reached a heat balance, a temperature and a relative humidity of an air-gap in the soil are detected simultaneously by the elements 1, 2. According to this constitution, soil water can be detected without having a mechanical mechanism and without causing a measuring error due to a soil temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a soil moisture detection terminal used for automating water supply in greenhouse horticulture and the like.

Conventional technology Water supply in the field of greenhouse horticulture generally relies on human experience and intuition, making accurate water supply impossible and difficult to automate. Therefore, there has been a demand for a soil moisture detection end that can accurately measure soil moisture and is highly reliable.For this reason, conventional soil moisture detection ends have been developed using, for example, strip-shaped nylon ribbons to detect moisture. The device was housed in a cylindrical case with an opening, and this case was buried in the soil to utilize mechanical expansion and contraction due to surrounding humidity to detect moisture in the soil.

Problems to be Solved by the Invention However, in conventional soil moisture detection terminals, a nylon ribbon is used as the detection element, and its mechanical expansion and contraction is the principle of moisture detection. There were problems such as measurement errors due to differences in soil temperature.

The present invention has been made in consideration of the above-mentioned problems, and aims to provide a highly reliable soil moisture detection terminal with a compact detection terminal mechanism and less soil temperature error.

Means for Solving the Problems In order to achieve the above object, the underground sensing end of the present invention includes an electronic temperature sensing element and a humidity sensing element, and houses these sensing elements, and has an acute-angled tip. The cylindrical case has an opening in the lower side surface and a lead wire hole for the temperature and humidity sensing element in the upper side surface, and the temperature and humidity sensing element is provided near the opening.

Function: With this configuration, the temperature and absolute moisture in the soil are electrically detected by the electronic temperature and humidity sensing element.

EXAMPLE An example of the present invention will be described below with reference to FIGS. 1 and 2. In FIG. 1, 1 is a temperature sensing element, and 2 is a humidity sensing element, both of which are made of a ceramic semiconductor material. Reference numeral 3 is a lead wire electrically connected to the temperature sensing element 1 and the humidity sensing element 2. Reference numeral 4 denotes a support base on which the temperature sensing element 1, the humidity sensing element 2, and the lead wire 3 are fixed.

Reference numeral 5 denotes a case, and 6 a threaded portion.The case 5 has a cylindrical shape with a pointed tip, and its upper and lower parts are joined by the threaded portion 6. The support stand 4 is located at the joint between the upper and lower parts of the case 6, and is fixed within the case 6 with a screw portion 6. Reference numeral 7 denotes an opening, which has a mesh-like shape and is made of a water-repellent material.

It is located on the lower side of the case S and faces the detection element 1.degree.2. Reference numeral 8 denotes a lead wire extraction hole located on the upper side surface of the case 5. 9 is a hammer head, which is installed at the top of the case 6. A scale 1o is provided on the upper side surface of the case 6, and the distance from the center of the opening is graduated.

In the above configuration, the case 6 is stood perpendicular to the soil surface, the hammer head 9 is struck with a hammer, and the detection elements 1 and 2 are placed in the soil at the roots of the cultivated plants using the scale 1o as a guide. Insert into. Then, when the surrounding soil and the sensing end reach thermal equilibrium, the temperature and relative humidity of the soil void in equilibrium with the soil moisture are detected through the opening 7 by the sensing element 1, respectively.
2 and converts it into an electrical signal via a lead wire.

In this way, the soil temperature is detected simultaneously with the relative humidity, and the relative humidity is detected electrically rather than mechanically.

As described above, according to this embodiment, by using a temperature and humidity sensing element made of a ceramic semiconductor material as a sensing element, detection errors due to differences in soil temperature can be eliminated, and there is no mechanical mechanism. Temperature and humidity can be detected electrically, making the detection end more compact.

FIG. 2 shows a second embodiment, in which the humidity sensing element is constructed of a heating cleaning type humidity sensing element 11.

According to this configuration, characteristic deterioration due to adhesion of contaminants in the soil to the humidity sensing element can be regenerated by heating cleaning, and the reliability of the soil moisture sensing element is improved and its lifespan is extended.

Effects of the Invention As is clear from the description of the embodiments above, the present invention includes a temperature sensing element, a humidity sensing element, and a method for storing these sensing elements.
A cylindrical case having an acute-angled tip, an opening on the lower side surface, and a lead wire extraction hole for the temperature and humidity sensing element on the upper side surface, and the temperature and humidity sensing element is provided near the opening. Because of this, it is possible to create a compact detection end that does not have a mechanical mechanism and is free from measurement errors due to differences in soil temperature, and its industrial effects are significant.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a soil moisture detection end in one embodiment of the present invention, and FIG. 2 is a sectional view of a soil moisture detection end in another embodiment. 1... Temperature detection element, 2... Humidity detection element, 3... Lead wire extraction hole, 5...
-Case, 7...Opening, 8...Lead wire, 10...Scale.

Claims (4)

[Claims] (1) It houses a temperature sensing element, a humidity sensing element, and these temperature and humidity sensing elements, and has an acute-angled tip, an opening on the lower side, and a lead wire for the temperature and humidity on the upper side. A soil moisture detection end comprising a cylindrical case having a take-out hole, the temperature and humidity detection element being provided near the case opening. (2) The soil moisture detecting device according to claim 1, wherein the humidity detecting element is a heating cleaning type humidity detecting element. (3) The soil moisture detection end according to claim 1, wherein the case opening is formed of a waterproof material. (4) The soil moisture detection end according to claim 1, wherein a scale is formed on the side surface of the case to indicate the distance from the opening.