JPS6327829U - - Google Patents

Description

[Brief explanation of the drawing]

Fig. 1 is a diagram showing the liquid level detection principle of the sensor section of this invention, Fig. 2 is a diagram showing the relationship between the liquid level of the conical part of the sensor and the light receiving power of the optical fiber, and Fig. 3
The figure shows the relationship between the liquid level of the multi-stage conical lens and the light receiving power of the optical fiber, Figure 4 shows one embodiment of this invention, and Figure 5 shows another embodiment used in the collimating lens. A cross-sectional view of the sensor and its surroundings when this occurs, and FIG. 6 are schematic diagrams showing conventional detection means. In the figure, 1 is an optical fiber, 2 is a collimating lens, 3 is a conical lens, 4 is a liquid level, 5 is an incident light, 7 is a reflected light, 8 is a multistage conical lens, 9
10-1 and 10-2 are a conical part, 10-1 and 10-2 are cylinder parts, 11 is a truncated cone part, 12 is a light source, 13 is an enlarged collimating lens, 14 is a beam splitter, 15 is a coupling lens, and 16 is a photoelectric conversion part. Note that the same reference numerals in each figure indicate the same or corresponding parts.

Claims (1)

[Claims for Utility Model Registration] (1) A non-conductive liquid level sensor comprising: a light projecting means; a light projecting fiber that projects light from the light projecting means; The collimating lens to be connected and the collimating lens that is joined to the collimating lens and whose tip has an apex angle of 9
The inclination angle of the cylindrical part and the side wall is 45 degrees in the conical part which is 0 degrees.
A sensor whose diameter gradually decreases in a stepwise direction from the junction of the collimating lens in the direction of the tip by connecting one or more body parts with a truncated cone part having a diameter of 90 degrees, or the tip has an apex angle of 90 degrees. Connect one or more body parts each consisting of a polygonal prism part and a polygonal truncated pyramid part whose opposite sides are parallel and whose side plate inclination angle is 45 degrees to a polygonal pyramid part whose opposite sides are parallel, and from the collimating lens junction part. and a sensor whose sides gradually contract in a stepwise direction, and the sensor controls the amount of light projected through the collimating lens from the side wall or the side plate depending on the degree of contact with the liquid on the side wall or the side plate. a light-receiving optical fiber that changes the amount of reflection and receives the reflected light reflected from the side wall or the side plate via the collimating lens; and a photoelectric conversion that converts the light received by the light-receiving fiber into an electrical signal. and converting the electrical signal output of the photoelectric conversion means into a predetermined output according to the position of the liquid contacting part of the conical part and one or more truncated conical parts, or the polygonal pyramid part or one or more truncated polygonal pyramid parts of the sensor. and a plurality of comparison output means for outputting a signal indicating the presence or absence of the liquid in contact with the liquid at each position, the transmitting light fiber and the receiving light fiber share one optical fiber. A liquid level sensor that is an optical fiber that emits and receives light. (2) The light projecting means includes: a point-emitting light source; an expanding collimating lens that expands the distribution of the light emitted by the point-emitting light source; and transmitting the light that has been expanded in distribution by the expanding collimating lens, and Practical use characterized by comprising: a beam splitter that changes the incident direction of the reflected light; and a coupling lens that collects the light that has passed through the beam splitter and projects it onto the projection light fiber. A liquid level sensor according to claim 1 of the patent registration claim. (3) The liquid level sensor according to claim 1, wherein the collimating lens is a distributed index rod lens. (4) The collimating lens is a cylinder with a hollow interior, and the wall on the opposite side of the light emitting/receiving optical fiber has a shape having a convex surface on the side of the light emitting/receiving optical fiber. A liquid level sensor according to claim 1 of the patent registration claim. (5) Utility model registration claim 1, characterized in that the photoelectric conversion means includes a photoelectric conversion element.
Liquid level sensor described in section.