JPH0257225A - Dust detector for vacuum cleaner - Google Patents

Abstract

PURPOSE:To improve detecting accuracy without being directly influenced by variations of a wavelength of infrared rays from outer light, by a method wherein members near a light emitting diode and a light sensor are made in a pitch- dark color or in rich color. CONSTITUTION:Opening parts are provided opposite each other in part of a dust-sucking way 2, and a light emitting diode 7 and a light sensor 8 are located opposite each other in that place. Covers 9, 10 are so formed as to cover the light emitting diode 7 and the light sensor 8. The covers 9, 10 and the dust- sucking way 2 are also formed by resin-molded parts which is not easy to transmit or reflect infrared rays from outer light and wall parts 2a, 2b near each device constituting a sensor part in the dust-sucking way 2 are painted in a pitch-color or in a rich color. Since this detector is so formed that the light sensor 8 of the sensor part receiving light is not influenced by variations of out light, it is possible to make sharp a sensibility of a detecting part 16 and to upgrade the detecting accuracy of the dust detector so possible as to detect fine dust.

Description

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

2. Description of the Related Art Conventionally, this type of dust detection device has a light emitting element and a light receiving element facing a dust suction passage.

The light emitted from the light emitting element is mainly infrared wavelength light, and this light is blocked and the amount of light reaching the light receiving element changes depending on the amount of dust, and the rotation of the fan motor is controlled by changing the output of this light receiving element. or the display would be activated.

By the way, the biggest problem with optical detection means is that the output from the light-receiving element changes depending on the amount of light received, so it is not affected by changes in external light from the surroundings, and changes in the light wind from the light-emitting element become large. The sensitivity of this light-receiving element had to be made dull so that it would only react when the sensor was activated.

Problems to be Solved by the Invention However, if the sensitivity of the light-receiving element is reduced to reduce the influence of changes in external light, it will not be able to cope with changes in the amount of light caused by fine dust. Detection accuracy was not good. Also, under strong light such as direct sunlight,
Changes in the shadows of objects caused by cleaning work may transmit and reflect through the cover covering the light-emitting element and light-receiving element and the dust suction passage, causing a change in the intensity of light to the light-receiving element and performing the same operation as dust detection. In order to take this countermeasure, there was a problem in that the detection accuracy had to be significantly reduced.

The present invention solves these conventional problems,
This is to reduce the influence of infrared wavelength light of external light and prevent the accuracy of the dust detection device from deteriorating.

Means for Solving the Problems The first means of the present invention to achieve the above object is to make the members near the light emitting element and the light receiving element dark black or deep colored, and the second means is as follows: The cover covering the light emitting element and the light receiving element and the dust suction passage are constructed of resin molded parts containing an infrared absorbing material. The hose connected to the suction port of the vacuum cleaner is composed of a core material and upper and lower winding tapes that sandwich the core material, and at least one of the winding tapes is dark black or dark colored.

The dust detection device of the present invention has the above-mentioned configuration so that the intermittent changes in the weak light intensity of the dust detection device caused by the passage of dust are not affected by the strong changes in external light, and the first means is as follows. According to the above, external light is blocked and the influence of external light on a light receiving element is reduced.

According to the second method, the cover covering each element and the dust suction passage are made of resin molded parts containing an infrared absorbing material that approximates the infrared wavelength light emitted from the light emitting element, so that external light such as direct light is prevented. When transmitting and reflecting through resin molded parts, it blocks light with wavelengths similar to the infrared light emitted from the light emitting element, so changes in external light do not reach the light receiving element, and changes in the amount of light due to dust purely passing through the light flux area are prevented. It is something that can be grasped.

According to the third means, the light transmitted and reflected through the hose portion is prevented from reaching the sensor light receiving element, thereby reducing the influence of external light.

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

In Fig. 1, reference numeral 2 denotes a dust suction passage formed integrally with the operating hand/I/1, the upstream end of which is connected to the floor nozzle/I/4 via an extension pipe 3, and the downstream end of the dust suction passage. The section is connected via a hose 5 to an inlet side 6 of the vacuum cleaner.

A part of the dust suction passage 2 has openings facing each other, and a light emitting element 7 and a light receiving element 8 are disposed to face each other. Covers 9 and 1o are configured to cover the light emitting element 7 and the light receiving element 8, respectively.

Further, a hose 6 is connected to the downstream end 11 of the dust suction passage 2. This hose 5 maintains its cylindrical shape and is composed of an upper tape 14 and a lower tape 15 to sandwich a piano wire 12 as a core part for flexibility, a conductive wire 13, etc., and at least One side is dark black or dark colored.

In addition, the covers 9 and 1o of each element and the dust suction passage 2 are made of resin molded parts that are difficult to transmit and reflect external infrared light, and the vicinity of each element that constitutes a part of the sensor of the dust suction passage 2 is The walls 2a, 2b are painted in dark black or deep color.

The light receiving element 8 is connected to the detection unit 16 and converts the amount of light reaching the light receiving element 8 from the light emitting element 7 into an electrical signal, and the detection unit 16 detects the amount of dust in the dust suction passage 2 based on the amount of change in this signal. For example, it is used to control the rotation of a fan motor or to control the display of a display.

In such a configuration, the infrared wavelength light reaching the light receiving element 8 from the light emitting element 7 is blocked by the dust passing through the dust suction passage 2, but at this point, changes in external light are not influenced by the light receiving element 8 of the sensor light receiving section. By not doing so, the sensitivity of the detection unit 16 can be increased, and the detection accuracy of the dust detection device can be increased so that even fine dust can be detected.

Effects of the Invention As is clear from the above embodiments, according to the present invention, detection accuracy can be improved without being directly affected by changes in infrared wavelength light of external light.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway side view of an operating handle of a vacuum cleaner showing an embodiment of the present invention, and FIG. 2 is an overall side view. 1... Operation handle, 2... Dust suction passage, 2a. 2b...Dust suction passage wall, 6...Hose, 7...Light emitting element, 8...Light receiving element,
9,10...Cover 14...Top tape, 15...Bottom tape, 16...
Detection part. Name of agent: Patent attorney Shigetaka Awano and one other person Toni Rin1

Claims (3)

[Claims] (1) A dust suction passage and a detection unit disposed in the dust suction passage that detects the amount of dust in the dust suction passage based on the amount of light reaching the light emitting element and the light receiving element, and detecting the amount of dust in the dust suction passage, Vacuum cleaner dust detection device in dark black or dark color. (2) A dust detection device for a vacuum cleaner in which the cover covering the light emitting element and the light receiving element and the dust suction passage are made of resin molded parts containing an infrared absorbing material. (3) The hose that connects the operating handle part with the dust suction passage facing the light emitting element and the light receiving element and the suction port of the vacuum cleaner is composed of a core material and upper and lower tape wraps that sandwich the core material, and at least one of the tape wrappers is Vacuum cleaner dust detection device in dark black or dark color.