JPH02152425A - Dust detector for vacuum cleaner - Google Patents

Abstract

PURPOSE:To contrive a light receiving element and a light emitting element, not to be oscillated against an impact from an external section, and eliminate erroneous working by shielding the light emitting element and the light receiving element for composing a detecting section for detecting dust in a suction passage, with a light- impermeable cover, except the front surfaces of said elements. CONSTITUTION:On a section confronted with the passage wall of a suction passage 11 with one end connected to the suction chamber of a fan motor, a light emitting element 12 and a light receiving element 13 are arranged. The light emitting element 12 permits the front surface 14 of a light emitting surface to be faced into the suction passage 11, and the side sections are shielded with light-impermeable covers 15. Besides, a connecting section 17 with a connecting wire 16 is also integrally sealed. Then, the side sections of the light receiving element 13 are also shielded with light- impermeable covers 15' in the same manner, and the front surface 14' is faced into the passage 11. Besides, the light receiving element 13 is connected to a detecting section 18, and a light quantity reaching the light receiving element 13 from the light emitting element 12 is converted to the electric signal. Based on the electric signal thus converted, dust in the passage 11 is detected by the detecting section 18, and in accordance with the collected dust, the rotation control or the like of the fan motor is performed.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a dust amount detection device for a vacuum cleaner that detects the amount of dust flowing into a suction passage.

BACKGROUND OF THE INVENTION In recent years, there has been a strong desire to improve the cleaning ability of vacuum cleaners, and for this reason, fan motors have been controlled in accordance with the amount of dust sucked in.

The configuration of a conventional dust detection device for a vacuum cleaner that detects the amount of suctioned dust will be explained with reference to FIG. As shown in the figure, an opening 1a is provided in a part of a suction passage 1 through which dust is sucked in by a fan motor, and a light emitting element 2 and a light receiving element 3 are provided which face into the passage 1 through this opening 1a. The light output from the light emitting element 2 reaches the inner surface of the passage 1, the reflected light reaches the light receiving element 3, the amount of light reaching the light receiving element 3 is converted into an electrical signal by the light receiving element, and is input to the detection unit 4. be done.

The detection unit 4 uses the fact that the amount of reflected light reaching the light receiving element 3 changes depending on the amount of dust in the passage 1.
The amount of dust is detected according to the signal from the sensor.

FIG. 4 also shows a perforated cover 8 that prevents dust in the suction passage 6 from adhering to the light emitting element 6 and the light receiving element 7 and causing malfunction.
．． The number 9 is used to indicate the number.

Problems to be Solved by the Invention However, in the conventional configuration shown in FIG. 3, since the light emitting element 2 and the light receiving element 3 are disposed within the opening 1a, when dust flows in the passage 1 as shown by arrow A, , turbulent flow occurs near the opening 1a, dust accumulates or adheres to that area, the amount of light reaching the light-receiving element 3 from the light-emitting element 2 changes, and the adhesion of dust progresses over long-term use, resulting in poor detection accuracy. However, there was a problem in that there was a significant decrease in

Furthermore, in the example shown in FIG. 4 which solves the above problem, the light emitting element 6. The light receiving element 7 may come into delicate contact with the translucent cover 9 and malfunction due to external vibrations, and in order to solve this problem, a large amount of assembly time is required. The purpose of the present invention is to provide a detection device that does not malfunction while avoiding an increase in assembly man-hours and costs.

Means for Solving the Problems In order to achieve the above object, the first means of the present invention is to detect dust in the suction passage according to light reaching a light receiving element from a light emitting element facing into the suction passage. The light-emitting element and the light-receiving element are configured such that the light-emitting element and the light-receiving element are covered with a non-transparent cover except for the front surface.

In the second method, the light emitting element and the light receiving element are integrated with the same cover.

Effect In the first means described above, the light-emitting element and the light-receiving element are shielded with a non-light-transmitting cover except for the front surface, and are not fixed with a printed circuit board, so that the light-receiving and light-receiving elements are able to protect themselves from external shocks. Eliminates malfunctions without vibration. Furthermore, since it is integrated with a non-transparent cover, malfunctions caused by unnecessary transmitted light can be prevented, and stable products can be provided without increasing costs.

The second method is that the light-emitting element and the light-receiving element are integrated with a non-light-transmitting cover, which reduces assembly man-hours by concentrating parts and improves the accuracy of the positional relationship between the light-receiving element and the light-emitting element. This allows us to provide more stable products.

Example Embodiments of the present invention will be described below with reference to FIG.

In the figure, 11 is a fan motor (not shown) at one end.
A light-emitting element 12 and a light-receiving element 13 are disposed on opposing portions of the wall of the suction passage connected to the suction chamber.

The light emitting element 12 has a front UfiJ 14, which is a light emitting surface, facing into the suction passage 11, and the side portion is shielded by a non-transparent cover 16. Furthermore, the connecting portion 17 with the connecting wire 16 is also integrally sealed.

On the other hand, the sides of the light receiving element 13 are similarly shielded by non-transparent covers 15', and the front surface 14' faces into the passage 11.

Further, the light receiving element 13 is connected to a detection section 18, and converts the amount of light reaching the light receiving element 13 from the light emitting element 12 into an electrical signal. The detection section 18 detects dust in the passage 11 based on this electric signal.

Next, the operation will be explained. When the fan motor is operated to start sucking in dust, the dust flows through the passage 11 as shown by arrow A. On the other hand, the transmittance of the light from the light emitting element 12 decreases as more dust flows through the passage 11, making it more difficult for the light to reach the light receiving element 13, and the amount of light detected by the light receiving element 13 decreases.

Based on the detection signal from the light receiving element 13, the detection unit 1
B detects dust and performs hearsay control of the fan motor depending on the dust. However, since the light emitting element 12 and the light receiving element 13 are not fixed on a printed circuit board or the like by shielding the parts other than the front surface 14 with a non-transparent material, the light receiving element 13 and the light emitting element 12 are not susceptible to external impact. On the other hand, they do not vibrate on their own, and as a result, their optical axes do not deviate from each other, which eliminates malfunctions caused by changes in the amount of light. Furthermore, since the non-transparent covers 15 and 15' are integrated, it is possible to prevent the detection unit 18 from malfunctioning due to scattering of unnecessary transmitted light, and it is possible to provide a stable product without a cost increase.

Next, another embodiment of the present invention will be described with reference to FIG. In this embodiment, as shown in the figure, a light emitting element 12 and a light receiving element 13 are integrated with a non-transparent cover 19 and arranged.

That is, the light emitting element 12 emits light into the suction passage 11, and the light receiving element 13 detects the amount of light reflected to detect dust. Moreover, by providing a unit of multiple elements, each other's light can be detected. The dust detection range is expanded within the passageway while minimizing interference with dust, making it easier to detect dust stably without malfunction.

Effects of the Invention As described above, the present invention includes a detection unit that detects the amount of dust in the suction passage according to light reaching the light receiving element from a light emitting element facing into the suction passage, and the light emitting element and the light receiving element are Since everything except the front surface is shielded with a non-light-transmitting material, the light receiving element 1 light emitting element does not vibrate by itself in response to external shocks, and as a result, the optical axes of each other do not shift, and changes in light intensity are prevented. It is possible to eliminate malfunctions due to Since it is integrated with a non-transparent cover, it is possible to prevent the detection unit from malfunctioning due to scattering of unnecessary transmitted light.

Furthermore, by reducing costs through unitization, it is possible to provide cheaper and more stable products.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a dust detection unit of a vacuum cleaner showing a first embodiment of the present invention, and FIG. 2 is a cross-sectional view of a dust detection unit of a vacuum cleaner showing another embodiment of the present invention. 3 and 4 are cross-sectional views of a conventional dust detection device for a vacuum cleaner. 11... Suction passage, 12... Light emitting element, 1
3... Light receiving element, 15.15'... Non-transparent cover 18... Detection section. Name of agent: Patent attorney Shigetaka Awano and 1 other person5-
n Expected yS 1 is one--approximate stop word.惺

Claims (2)

[Claims] (1) A detection unit is provided that detects the amount of dust in the passage according to light reaching the light receiving element from a light emitting element facing into the suction passage, and the light emitting element and the light receiving element are non-transparent except for the front surface. A vacuum cleaner dust detection device configured by shielding with a cover. (2) The dust detection device for a vacuum cleaner according to claim 1, wherein the light emitting element and the light receiving element are integrated with a non-transparent cover.