JPS6349496B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vacuum cleaner featuring a cooling configuration for semiconductor devices, and its purpose is to reliably cool semiconductor devices by utilizing the inherent characteristics of vacuum cleaners. shall be.

In recent years, vacuum cleaners with power consumption control devices have been commercialized from the perspective of energy conservation, and these control devices are equipped with bidirectional three-terminal control in order to reduce manufacturing costs and provide diverse functions. Elements such as rectifying elements have come into use. In addition, magnetic relays were conventionally used to turn on and off the power by remote control, but due to reasons such as dust getting into the contacts and poor durability, semiconductor relays were considered and put into practical use. It has been. When using semiconductor devices in vacuum cleaners, the most important consideration is how to prevent the semiconductor devices from overheating. Needless to say, semiconductor devices have the characteristic that they generate self-heating when current flows through them, and if this exceeds an upper limit, they will be destroyed.
Particularly in vacuum cleaners, the electric blower generates heat on its own, raising the exhaust temperature, and if the air inflow decreases due to a clogged filter, the exhaust passage temperature itself may approach the upper temperature limit of the semiconductor element. Something happened. For this reason, in the past, a method was used in which a heat sink was provided to which the semiconductor element was fixed, and this heat sink was installed on the intake side in front of the electric blower to cool it by the intake air flow. Another disadvantage is that the wiring structure becomes complicated to electrically connect the semiconductor element and the power supply section on the main body side of the vacuum cleaner, which increases the manufacturing cost.

The present invention solves these conventional problems, and one embodiment thereof will be described below with reference to the accompanying drawings. In the figure, 1 is a main body made of synthetic resin;
Reference numeral 2 denotes an electric blower supported within the main body 1 through a support 3 having elasticity, and 4 is a partition wall formed integrally within the main body 1 so that the support 3 is brought into close contact with the main body 1 to prevent air leakage. The support body 3 is held by being wound around the outer circumference of the blower section 2a of the electric blower 2, and its outer circumference is supported by contacting the partition wall 5 integrally formed with the main body 1, The wall 5, the support 3 and the outer wall 6 of the main body 1 form a compartment 7. The side of the partition wall 4 opposite to the contact surface of the support body 3 communicates with the front negative pressure section 8 of the electric blower 2, and is constantly cooled by air sucked in from the suction port 9 of the main body 1. Reference numeral 10 denotes a metal heat sink held and housed by a rib body 11 provided in the compartment 7, to which a semiconductor element 12 for controlling current is attached. The heat dissipation plate 10 is brought into close contact with the side of the partition wall 4 that is in close contact with the support body 3 to radiate heat to the partition wall 4 side and prevent the temperature of the semiconductor element 12 from rising excessively. 13
is the control circuit section and is housed in compartment 7. 14 is a lead wire connecting the control circuit section 13 and the power supply side.

Next, the electric circuit will be briefly explained based on FIG. The control circuit section 13 includes a trigger element 17 for sending a signal to the semiconductor element 12 fixed to the heat sink 10, a variable resistor 18 for adjusting the signal current of the trigger element 17, and a capacitor 19. The current flowing through the blower 2 is controlled to change the rotation speed of the electric blower 2. capacitor 2
0 is a protection circuit for the semiconductor element 12, and an input switch 22 for remote control.
An auxiliary element 23 that causes current to flow through the control circuit when turned off, a trigger element 24 that sends a signal to this auxiliary element 23, a capacitor 25, and a hand switch 22.
A resistor 26 is provided to turn the current flowing into a minute current.

In the above circuit, after applying voltage to the power supply,
When the hand switch 22 is turned on, the capacitor 25
A capacitance is stored in the auxiliary element 23, and when a constant voltage is reached, a signal is sent from the trigger element 24 and current flows to the auxiliary element 23. When the auxiliary element 23 becomes conductive, current flows through the control circuit, and when a certain capacity is stored in the capacitor 19, a signal is sent from the trigger element 17 to the semiconductor 12, and current flows through the main circuit, causing the electric blower 2 to rotate. do. The semiconductor element 12 generates self-heating due to the flow of a large current, and if a certain limit is exceeded, the junction part inside the semiconductor element 12 is destroyed, so it must be constantly cooled with a heat sink or the like.

In the above configuration, the compartment 7 is formed by the support 3 fitted around the outer periphery of the electric blower 2, the compartment 4, and the partition wall 5, and is isolated from the exhaust flow of the electric blower 2, so that the temperature can be reduced. Rising air does not flow in, and fine dust that has passed through the filter device does not adhere to the control circuit section 13.
Furthermore, the temperature of the heat sink 10 increases due to the self-heating effect of the semiconductor element 12, but since the heat sink 10 is in close contact with the partition wall 4, the heat is transferred to the partition wall 4, and the partition wall 4 is cooled by the suction air. Semiconductor element 12
The temperature rise is limited to a constant value. In addition, when assembling the product, the heat sink 10 and the control circuit section 13 are removed from the partition chamber 7.
Since the electric blower 2 is installed after the electric blower is stored in the holder, no extra effort is required for assembly.

Further, in this embodiment, a bidirectional three-terminal control rectifier element is shown as the semiconductor element 12, but it is obvious that the present invention is not limited to this.

As described above, according to the present invention, even if the semiconductor element generates heat by itself, the heat sink is isolated from the exhaust flow and is closely attached to the partition wall, so it can be easily cooled and a vacuum cleaner with fewer malfunctions can be used. Can be provided. Furthermore, in terms of ease of assembly, since the heat sink and the semiconductor element are arranged on the housing side of the electric blower, there is no need for special wiring processing or an air leak prevention structure, and the advantage is that it can be manufactured at low cost.

[Brief explanation of drawings]

Fig. 1 is a side view showing a section of a vacuum cleaner according to an embodiment of the present invention, Fig. 2 is a sectional view of a compartment of the same vacuum cleaner, and Fig. 3 is A of Fig. 2. -A
4 is a sectional view taken along line BB in FIG. 2, FIG. 5 is a sectional view taken along line CC in FIG. 1, and FIG. 6 is a circuit diagram of the vacuum cleaner. DESCRIPTION OF SYMBOLS 1... Main body, 2... Electric blower, 3... Support body, 4... Partition wall, 8... Front negative pressure part, 10... Heat sink, 12... Semiconductor element.

Claims (1)

[Claims] 1 The front side communicates with the front negative pressure part of the electric blower, and the rear side has a partition wall of the main body made of synthetic resin in which the front part of the support that supports the electric blower is brought into close contact with the outer periphery of the support body. a partition wall defined by the partition wall, a support body, and the partition wall; and a semiconductor element disposed within the partition chamber and having a metal heat sink, and the heat sink is located on the partition wall. A vacuum cleaner attached to the back.