JPH0525326U - Level switch - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a level switch that does not cause a malfunction of level detection even if an object to be measured that is input from above adheres. [Structure] The upper surface of the capacitance type detection unit 3 is covered with an insulator 4 so that malfunction does not occur even if an object to be measured such as a dehydrated cake 6 adheres to this portion.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a capacitance type level switch, and more particularly to a level switch suitable for being attached to a hopper for sewage sludge dewatering cake and detecting the level of the dewatering cake.

[0002]

[Prior Art]

 Capacitance type level switches detect the level of an object to be measured by utilizing the fact that the electrostatic capacity changes according to the amount of adhesion to the electrode of the object to be measured. It is used in the field to detect the level of dehydrated cake in the dehydrated cake hopper for feeding the dehydrated cake to the sludge incinerator.

In the above case, the sensitivity of the level switch is adjusted according to the properties of the dehydrated cake and used. However, since the dehydrated cake is fed into the hopper from above, the dehydrated cake Part of it inevitably adhered to the upper surface of the sensor, and malfunctions occurred frequently even when the sensitivity was adjusted. For this reason, it is necessary for an operator to put his / her hand through the inspection port to remove the dehydrated cake on the upper surface of the level switch, which is a major obstacle to automation.

[0004]

[Problems to be solved by the device]

 The present invention has been completed in order to solve the above-mentioned conventional problems and provide a level switch that does not cause a malfunction even if an object to be measured such as a dehydrated cake adheres to the upper surface. ..

[0005]

[Means for Solving the Problems]

 The present invention made in order to solve the above-mentioned problems is characterized in that the upper surface of the capacitance type detection unit is covered with an insulator.

[0006]

【Example】

 Hereinafter, the present invention will be described in more detail with reference to the illustrated embodiments. In FIG. 1, reference numeral 1 is a level switch of the present invention, and a detection unit 3 is attached to a dehydration cake hopper 2 so as to project as shown in the drawing. The detection unit 3 has a cylindrical shape with an electrode for measuring the capacitance inside, and its upper surface is covered with an insulator 4. As the insulator 4, for example, a resin such as silicon is used, and the coating angle may be about 90 to 180 degrees as shown in FIG.

[0007]

[Action]

 When the level switch 1 of the present invention configured as described above is used by being attached to the hopper 2 for dewatering cake, even when the dewatering cake 6 fed from the upper conveyor 5 adheres to the upper surface of the detection unit 3. Since the insulating material 4 is coated, no malfunction occurs due to the attached dehydrated cake 6. For this reason, by using the level switch 1 of the present invention, it is not necessary for an operator to put his / her hand through the inspection port to remove the dehydrated cake 6 from the upper surface of the level switch 1 as in the conventional case, and frequent inspection is required. This is convenient for automation because it does not need to be performed. The level of the dehydrated cake 6 in the hopper 2 for the dehydrated cake is detected by the level switch 1 of the present invention, and the input amount from the conveyor 5 is automatically controlled according to the output amount and kept constant.

[0008]

[Effect of the device]

 As described above, the level switch of the present invention does not have to be used for level detection, but rather, the upper surface of the detection unit that causes malfunctions is covered with an insulator to improve the level detection reliability. It is a thing. For this reason, the excellent effect can be obtained not only when it is used in the dehydration cake hopper described above, but also when it is used for other adherends to be measured. It should be noted that by covering the upper surface of the sensing portion for capacitance measurement with an insulator, no measurement error will occur, and even if some error occurs, it can be canceled by adjusting the sensitivity. It Therefore, the present invention has an extremely large practical value as a level switch that solves the conventional problems.

[Brief description of drawings]

FIG. 1 is a front view showing an embodiment of the present invention.

FIG. 2 is a side view showing a detection unit according to an embodiment of the present invention.

[Explanation of symbols]

 3 Capacitive sensing unit 4 Insulator

Claims (1)

[Scope of utility model registration request] 1. A level switch characterized in that an upper surface of a capacitance type detection section is covered with an insulating material.