JPS6152688B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a vacuum cleaner.

Generally, in the case of a vacuum cleaner, the suction air volume decreases due to an increase in the amount of dust collected, and the dust collection power decreases, so it is necessary to compensate for the decrease in the suction air volume by increasing the input to the electric blower. Therefore, conventionally, in a vacuum cleaner with a built-in electric blower 1 as shown in Fig. 1, a circuit board 2 and a relay 3 with built-in circuit members as shown in Fig. 2 are located inside the rear of the main body. It is protected from the exhaust heat of the blower 1, and a manual regulator 5 is provided inside the handle 4 at the top of the main body. As shown in FIG. 2, the electric blower 1 is connected to a power source via a cord reel 6, and has a relay contact 8 that is opened and closed by a relay 3 based on the operation of a hand switch 7.
and a triax 9 as an example of a power control element are connected in series. Here, a series protection circuit including a resistor R1 _and a capacitor _C1 is connected in parallel to the triac 9. A trigger element 10 such as a diagonal is connected to the gate of the triax 9, and the other end of the trigger element 10 is connected to a semi-fixed resistor R ₂ between the variable resistor R ₃ and the charging capacitor C ₂ in the manual regulator 5. It is connected to the. A hysteresis correction circuit including resistors R ₄ and R ₅ and a capacitor C ₃ is connected to the preceding stage of these. Therefore, the relay contact 8 is opened and closed for the power supply via the relay 3 by remote control operation of the hand switch 7 at the hand of the hose, and when in use, the input to the electric blower 1 is controlled by the triax 9 triggered by the trigger element 10. It has been adjusted. However, when the dust collection power decreases, the conduction angle of the triax 9 is reduced by varying the variable resistor _R3 by operating the manual regulator 5, and the input to the electric blower 1 is increased to reduce the suction air volume. Although this method compensates for the decrease in intake air volume, the input to the electric blower increases, which may lead to burnout of the electric blower. Also,
It is a manual adjustment and it is troublesome as you have to go back to the vacuum cleaner itself.

The present invention was developed in view of the above points, and it is possible to automatically control the input of the electric blower according to the load, that is, the intake air volume, thereby improving cleaning efficiency and preventing burnout of the electric blower. The purpose is to obtain a vacuum cleaner that can prevent the above.

In the present invention, when a leak air path is formed and the suction air volume decreases due to filter clogging, etc., the negative pressure on the electric blower side increases and the air volume flowing into this leak air path also increases. By detecting a change as a resistance change by a temperature detection element, the input of the electric blower can be automatically controlled using the detection signal.

A first embodiment of the present invention will be described based on FIGS. 3 and 4. Components that are the same as those shown in FIGS. 1 and 2 are designated by the same reference numerals, and description thereof will be omitted. First, as shown in FIG. 3, a dust collection intake passage 13 is formed through which air is taken in from a suction port 11 via a filter 12, and this dust collection intake passage 1
A leak air path 15 is formed which communicates with the outside air via the leak hole 14 while communicating with the outside air through the leak hole 14. and,
A temperature detection element 16 such as a thermistor is installed in the leak hole 14 so as to receive the amount of leak air. As shown in Figure 4, the circuit configuration is a semi-fixed resistor connected in parallel to the semi-fixed resistor _R2 .
A series circuit of R ₆ and temperature detection element R _T 16 is connected. Here, the temperature detection element 16 is simply R
Although it is shown as _T , in reality, a correction circuit is added within the element so that only the slope of the attenuation from the current temperature can be detected, and R _T is simplified to include this correction function. . Furthermore, semi-fixed resistors R ₂ and R ₆ are for manufacturing adjustment.

In such a configuration, semi-fixed resistors R ₂ , R ₆
The conduction phase angle of the triax 9 is set based on the above, and the input to the electric blower 1 is controlled by the triax 9. Therefore, during the suction operation, when the pressure loss in the dust collection intake air passage 13 is small, that is, when the filter 12 is not clogged and the intake air volume is large, the leak hole 14
Since the amount of leak air in the leak air path 15 is small, the resistance change of the temperature detection element R _T 16 is small, and the input to the electric blower 1 is maintained and controlled at the initial state.

However, as the amount of dust collected increases and the filter 12 becomes more clogged, the intake air volume of the dust collection intake air passage 13 decreases and the load increases, the leak air passage 15 is sucked in from the leak hole 14. The amount of leak air increases. At this time, the temperature detection element R _T 1
6 is located in the leak air path 15 and receives the amount of leak air, so it is cooled and its resistance attenuates and changes, making the conduction phase angle of the triax 9 smaller than the initial state and increasing the input to the electric blower 1. let This operation can be increased up to the upper limit of the rating of the electric blower 1. In this way, during cleaning, the input to the electric blower 1 is automatically adjusted based on the temperature detection element R _T 16 according to the degree of load, so cleaning efficiency can be improved without any troublesome operations. I can do it.

Next, a second embodiment of the present invention will be explained with reference to FIG. In this embodiment, as shown in FIG. 3, a manual regulator 5 is also used.
The variable resistor R ₇ and the temperature detection element R _T 16 in the semi-fixed resistor R ₆ can be switched by a changeover switch 17. This results in
Input control of the electric blower 1 can be performed either automatically or manually. Therefore, regardless of load fluctuations, it is possible to properly clean delicate parts etc. by manual control as needed. Here, in FIG. 5, the changeover switch 17 is the manual regulator 5.
It is shown as a volume with a switch linked to the
They may be provided separately (the same applies to the following embodiments).

Further, a third embodiment of the present invention will be explained with reference to FIG. Like the second embodiment, this embodiment also uses a combination of automatic and manual control, in which the variable resistor R ₇ of the manual regulator 5 and the temperature detection element R _T 16 are connected in series, and the temperature detection element R _T A changeover switch 17 is connected in parallel to 16. Thereby, when automatic control is performed by the temperature detection element R _T 16, the upper limit range that is automatically adjusted thereby is controlled by the variable resistor R ₇ . That is,
When the changeover switch 17 is ON, the temperature detection element R _T 16 is short-circuited and manual control is performed by the manual regulator 5. When the changeover switch 17 is turned OFF, automatic control is performed by the temperature detection element R _T 16, but the upper limit is the variable resistance. Variably controlled according to the value of _R7 . Therefore, even if the input is increased by changing the variable resistor _R7 as necessary, it can be manually adjusted within a range that does not interfere with cleaning, and cleaning can be performed with peace of mind.

Furthermore, a fourth embodiment of the present invention will be explained with reference to FIG. This embodiment also uses a combination method, in which a temperature detection element R _T 16, a semi-fixed resistor R ₆ and a changeover switch 1 are used.
7 is connected in parallel to variable resistor _R7 . This causes the changeover switch 17 to
When the temperature detection element R _T 16 is turned on and automatic control is performed, the lower limit range of the automatically adjusted input is controlled by the variable resistor R ₇ of the manual regulator 5. Therefore, in the event that something with a large specific gravity is left behind during cleaning and causes a problem, the lower limit of the input control can be adjusted to a point where nothing is left behind even during automatic adjustment.

As described above, the present invention provides a temperature detection element whose resistance value is variable according to the amount of leak air in the leak air path, and connects this to the power control element for input control of the electric blower. The input of the electric blower can be automatically controlled according to fluctuations, and the input of the electric blower is controlled to increase as the resistance value of the temperature detection element decreases, preventing burnout of the electric blower. The cleaning efficiency can be improved with a simple circuit configuration without any operation, and the reliability of the control can also be improved.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway side view showing a conventional example, Fig. 2 is a circuit diagram thereof, Fig. 3 is a partially cutaway side view showing a first embodiment of the present invention, and Fig. 4 is its circuit. 5 is a circuit diagram showing a second embodiment of the invention, FIG. 6 is a circuit diagram showing a third embodiment of the invention, and FIG. 7 is a circuit diagram showing a fourth embodiment of the invention. It is a circuit diagram. DESCRIPTION OF SYMBOLS 1... Electric blower, 9... Triax 9 (power control element), 13... Intake passage for dust collection, 15...
...Leak air path, 16...Temperature detection element.

Claims (1)

[Claims] 1. In a vacuum cleaner in which a dust collection chamber housing a filter and an electric chamber housing an electric blower are arranged side by side, a dust collection intake passage is formed between the filter and the electric blower, and this dust collection intake passage A leak passage communicating with outside air is provided in the leak air passage, and a temperature detection element whose resistance value decreases as the leak air volume increases is provided in the middle of the leak air passage, and this temperature detection element controls the input of the electric blower. A vacuum cleaner, characterized in that the vacuum cleaner is connected to a power control element and is controlled to increase the input to the electric blower as the resistance value of the temperature detection element decreases.