JPS6326129Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a suction force indicating device for a vacuum cleaner.

Conventionally, as shown in Figure 1, some vacuum cleaners have one end connected to an air path that connects the exhaust side of a dust collection chamber in which a filter is housed and the suction side of an electric blower chamber in which an electric blower is housed. transparent cylinder 1
An indicator 4 is constructed by housing a spring 2 and an indicator barrel 3 biased in one direction by the spring 2 in the cylinder 1.
Some indicators detect clogging of a filter that affects the suction force by operating an indicator tube 3 that slides in response to negative pressure, but such an indicator 4 has the disadvantage of having a large number of parts. Further, since the force of the spring 2 varies, the operation of the indicator tube 3 is not reliable, and therefore, there is a drawback that it is not possible to accurately determine the degree of clogging of the filter.

This invention was devised in view of these points, and the object is to obtain a suction force indicating device for a vacuum cleaner that has a small number of parts and has accurate detection accuracy.

This idea is based on a bellows section that is elastically biased in the direction of expansion and compresses in response to the negative pressure in the air path. The expansion and contraction movement of the expansion and contraction member according to the negative pressure in the air path can be determined by the position of the indicator. By forming the bellows portion gradually thinner toward the end, the elastic portion of the bellows portion gradually transitions from the thinner portion to the thicker portion in the axial direction, thereby preventing the elastic member from bending in the axial direction. , the telescopic member is configured to smoothly extend and retract so that clogging of the filter can be accurately detected.

An embodiment of this invention will be described with reference to Figures 2 to 4. First, a dust collection case 10 and a main case 11 are detachably attached. The dust collection case 10 is formed with a suction port 12 and a dust collection chamber 14 which houses a filter 13. The main case 11 is formed with an electric blower chamber 16 which houses an electric blower 15, an air passage 17 which connects the suction side of the electric blower chamber 16 with the exhaust side of the dust collection chamber 14, and an exhaust hole 18.

The main body case 11 is provided with a hollow cylindrical elastic member 19 made of an elastic material such as rubber or plastic. On the outer periphery of the other end of this telescopic member 19 is an indicator portion 21 that is visible through the viewing window 20 of the main body case 11.
An opening 22 is formed at one end to be fixedly held while communicating with the air passage 17, and a bellows part 23 which is biased in the direction of extension by its own elasticity is formed in the longitudinal wall part. has been done. This bellows part 2
3 is gradually reduced toward the other end of the elastic member 19. In addition, the elastic member 19
A leak hole 24 communicating with the outside of the main body case 11 is formed at the other end, and a support portion 25 formed in the main body case 11 is inserted into the leak hole 24 along the longitudinal direction.

In such a configuration, when the electric blower 15 is driven, dust is sucked in together with the suction airflow, captured by the filter 13, and accumulated in the dust collection chamber 14.
The suction airflow purified by the filter 13 is passed through the air passage 17,
The air is discharged to the outside of the main body case 11 through the electric blower chamber 16 and the exhaust hole 18 . When the filter 13 becomes clogged, the negative pressure in the air passage 17 increases, and in response to the increase in negative pressure, the bellows part 2 of the expandable member 19
3 shrinks. This amount of movement is measured as the amount of movement of the instruction section 21 and indicates the clogging state of the filter 13. At this time, the thickness of the bellows part 23 gradually decreases toward the other end of the elastic member 19, so that the part that shrinks is from the other end of the thin part to one end of the thick part. Since the telescopic member 19 moves sequentially and is further guided by the support portion 25, the axis of the telescopic member 19 is bent and the outer periphery does not touch the surrounding wall, and the contraction operation is performed smoothly. Therefore, detection of the clogging state of the filter 13 is accurate. When the negative pressure in the air passage 17 increases further due to clogging of the filter 13, the leak hole 24 slips out from the support part 25 and is fully opened due to the contracting action of the bellows part 23, and the outside air is passed through the elastic member 19 and the air passage 17 to the electric blower room. 1
6, the electric blower 15 is cooled and does not overheat.

In addition, when the negative pressure in the air passage 17 becomes low due to stopping the drive of the electric blower 15, etc., the elastic member 19 that has been contracted in this way tries to expand and return to its original state by expanding the bellows portion 23, but it returns to its original state initially. Since the thin portion of the bellows portion 23 is located on the other end side close to the support portion 25, the support portion 25 can be smoothly inserted into the leak hole 24 without shaking the other end of the elastic member 19.

In this way, the expandable member 19 integrally includes the indicator 21 and is biased in the expansion direction by its own force due to the formation of the bellows portion 23, thereby reducing the number of parts.

As described above, this device has an indicator portion on its outer periphery, and a bellows portion that elastically expands and contracts in response to the negative pressure in the air path, so that the filter eye can be seen. The number of parts required to detect a blockage can be reduced, and by making the wall thickness of the bellows part gradually thinner toward the tip along the axis, the expanding and contracting part of the bellows part can be reduced. It is possible to sequentially transition from a thin section to a thick section along the axial direction, thereby preventing the elastic member from bending in the axial direction during expansion and contraction, preventing contact with external components, and smoothing the expansion and contraction operation. This has effects such as being able to accurately detect clogging of the filter.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal side view showing a conventional example, Fig. 2 is a longitudinal side view showing the whole of an embodiment of this invention, and Fig. 3
The figure is a longitudinal sectional side view showing a part thereof enlarged, and FIG. 4 is a longitudinal sectional side view showing a state in which the bellows part of FIG. 3 is contracted and the leak hole is fully opened. 13... Filter, 14... Dust collection chamber, 15...
Electric blower, 16...Electric blower room, 17...Air path, 19...Extensible member, 21...Instruction section, 23...
...A bellows belly.

Claims (1)

[Scope of utility model registration request] An air passage is provided to connect the exhaust side of the dust collection chamber in which the filter is housed and the suction side of the electric blower chamber in which the electric blower is housed. A hollow cylindrical expandable member that expands and contracts in the direction is provided, the base end of the expandable member is connected to the air passage, the tip is in a free state, and the wall thickness of the bellows part is directed toward the tip side along the axis. A suction force indicating device for a vacuum cleaner, characterized in that the suction force is gradually thinner.