JPH01135326A - Electric cleaner - Google Patents

Abstract

PURPOSE: To enhance safety by holding the input changeover resistor of an electromotor by a magnetic fixing metal fitting and fixing the same to an air guide made of a resin within the range attracted to the magnetic force of an electromotor. CONSTITUTION: An electromotive blower 1 is constituted of a DC electromotor 2, a fan 3 and an air guide 4 made of a resin. Further, the input changeover resistor 5 of the DC electromotor 2 is held by a magnetic fixing metal fitting 6 and fixed to the air guide within the magnetic force acting range of the DC electromotor 2. As a result, even in the worst case such as a safe device such as a fuse is not operated at a time of the abnormality of the lock or the like of the electromotive blower 1, the resistor 5 is attracted and attached to the electromotor along with the fixing metal fitting 6 by the magnet of the electromotor. Therefore, the resistor is not exposed to the outside and there is no danger of ignition and safety becomes high.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a vacuum cleaner for general household use.

2. Description of the Related Art Most modern vacuum cleaners are input-switchable, and resistors are generally used as a means of switching inputs because they are inexpensive.An example of this is explained below with reference to Figure 2. .

21 is a DC motor 22, 77 n 23, air guide 24
An electric blower 26, a switch 26, and a battery 27
28 is a dust collecting box having a suction port 29 at the tip and a filter 30 inside, and is detachably attached to the main body 21. Reference numeral 31 denotes an input switching resistor held by the fixing member 3≧, and is attached to the rear of the air guide 24 with a screw 33 in order to promote effective cooling of the resistor 31. Furthermore, the air guide 24 is made of resin because it is inexpensive and lightweight. Reference numerals 34 and 36 are fuses provided to prevent a fire in the vacuum cleaner body 21 and burnout of the electric motor 22 due to heat generated by the electric motor 22 and the resistor 31 when the electric motor 22 is locked. 34 does not pass through the resistor 31, and the fuse 36 is connected in series with the resistor 31. The former will be referred to as "strong" and the latter as standard J circuit. Here, depending on whether the current passes through the input switching resistor 31 or not, the electric blower 2
5 input is switched.

Problems to be Solved by the Invention In the above configuration, a fuse is provided for safety, but even in the worst case where the fuse does not operate, the risk of fire must be prevented.

If the user forgets to turn off the vacuum cleaner and leaves it unattended, the danger becomes even greater, especially since rechargeable vacuum cleaners have an internal power source.

The situation when a fuse does not operate will be explained using a conventional example. When the electric blower locks up for some reason and the fuse does not operate, a large current of several tens of amperes flows in the "strong" circuit, causing the lead wires to break instantly, causing smoke, but not before ignition. Not enough. In the "Standard" circuit, even in the "Strong" circuit, a large current does not flow, so the lead wires do not break and the motor 22 and fuse 3
6, the current continues to flow. At this time, the resistor 31 reaches a temperature of several hundred degrees because there is no cooling at all. Therefore, the heat of the resistor 31 is transmitted to the fixture 32, and when the fixture 32 is attached, the air guide 24 is melted, making it difficult to hold the resistor 31. In the worst case scenario, the main body will also melt and be exposed to the outside. If there is anything flammable nearby, there is a risk of it catching fire.

The present invention eliminates the @ point in the prior art.
The purpose is to provide a highly safe vacuum cleaner.

Means for Solving the Problems The present invention solves the above-mentioned conventional drawbacks by holding the input switching resistor of the electric motor with a magnetic fixture, and
It is fixed to a resin air guide within the range where it is attracted by the magnetic force of the electric motor.

Effect: By taking the above-mentioned technical means of the present invention, when the electric blower is locked, the temperature of the resistor increases rapidly due to the lack of cooling air, which is transmitted through the fixing fittings and softens the fixing part of the resin air guide. , the resistor tries to fall, but the magnet of the motor attracts the resistor along with the identification metal fittings and attracts the motor.

Therefore, the resistor is not exposed to the outside and there is no risk of fire.

EXAMPLE An example of the present invention will be described below with reference to FIG. 1st
The figure is a configuration diagram of a DC electric blower. 1 company DC motor 2
, a fan 3, and a resin air guide 4; 7 Behind the shear guide 4 and the DC motor 2
It is installed within the range where it is attracted by the magnetic force of the built-in magnet.

As is clear from the above configuration, when the resistor 6 and the DC motor 2 are in series and the DC motor 2 is locked, the resistor 6
Since there is no air to cool the resistor 5, the temperature of the resistor 5 rises rapidly. This heat is transmitted through the fixing metal fitting 6 and the oil-proof air guide 4
The resistor 6 tries to fall by softening the fixing part of the resistor 6, but the magnet of the DC motor 2 attracts the resistor 5 together with the fixing fitting e to the DC motor 2 and attracts it. Furthermore, since the resistor 5 is attracted to the DC motor 2, heat is transferred to the outer shell of the DC motor 2, promoting heat radiation and suppressing temperature rise. Therefore,
The resistor 5 is not exposed to the outside and the risk of fire is reduced.

Effects of the Invention As described above, the present invention provides a highly safe vacuum cleaner that reduces the risk of fire even in the worst case where safety devices such as fuses do not operate in the event of an abnormality such as locking of an electric blower. It is.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway sectional view of a DC electric blower section of a rechargeable vacuum cleaner showing an embodiment of the present invention, Fig. 2 is a sectional view of a conventional rechargeable vacuum cleaner, and Fig. 3 is a circuit diagram of the same. It is. 1... Electric blower, 2... DC motor, 3... Fan, 4... Resin air guide, 6... Resistor, 6...Fixing metal fittings. Name of agent: Patent attorney Toshio Nakao and 1 other person/-
- Is it an electric transport machine? -Direct 2a Accent Motion 3---Fan 4---1 Air Card 5-11 Pay Raft

Claims (1)

[Claims] It has an electric blower consisting of a DC motor, a fan, and a resin air guide, and a resistance for switching the input of the DC motor.The resistance is held by a magnetic fixture, and the above resistance is controlled within the magnetic field of the DC motor. A vacuum cleaner fixed to an air guide.