JPH0753145B2 - Vacuum cleaner - Google Patents

Description

TECHNICAL FIELD The present invention relates to an electric vacuum cleaner having a switching element for controlling the rotation speed of an electric blower.

(Prior Art) In recent years, for example, a hand-held electric vacuum cleaner as shown in FIG. 5 and a canister-type electric vacuum cleaner that travels on the floor described in Japanese Utility Model Publication No. 58-98058 are known. And
The electric vacuum cleaner shown in FIG. 5 controls the suction force stepwise or steplessly so that the suction force suitable for the application can be obtained.
And a control circuit for controlling the terminal switching element 2,
The structure is such that the voltage input to the electric blower 3 is changed or the input is periodically turned off.

By the way, in an electric vacuum cleaner provided with these control circuits, the input current is usually several amperes, and if the current is attempted to be controlled by the three-terminal switching element 2 such as a transistor, the heat generation of the three-terminal switching element 2 becomes large. Therefore, the heat sink 4 is required. When the input current is large, the heat dissipation plate 4 also has to be large.

Reference numeral 8 is a rectifying plate having a diffuser function, which is provided so as to cover the fan 9 of the electric blower 3.

Therefore, in the cleaner body 5, the heat dissipation plate 4 to which the three-terminal switching element 2 is attached is separated from the circuit board 6 on which the control circuit is mounted, and is located in the air passage that connects the electric blower 3 and the exhaust port 7. By adopting such a structure, a structure for enhancing the cooling effect is adopted.

In addition, as shown in the description of Japanese Utility Model Publication No. 58-98058, 3
There is also known a structure in which a terminal switching element and a control circuit are attached to a heat radiating plate, and the heat radiating plate is positioned in an air passage that connects the electric blower and the exhaust port to enhance the cooling effect.

(Problems to be Solved by the Invention) In the conventional structure shown in FIG. 5, the space for accommodating the dedicated heat dissipation plate 4 is required in the air passage in the cleaner body 5, and therefore the cleaner body is required. There is a restriction on the downsizing of the vacuum cleaner 5, and if it is attempted to downsize the cleaner body 5, it becomes difficult to dispose the large heat dissipation plate 4 in the air passage, and the heat dissipation plate 4 must be made smaller. However, there is a problem that the 3-terminal switching element 2 having a large current capacity must be used and the expensive 3-terminal switching element 2 must be used.

Further, the structure described in Japanese Utility Model Laid-Open No. 58-98058 has the same problem.

The present invention is intended to solve such a problem, and is capable of sufficiently cooling the switching element, using an inexpensive switching element having a small maximum rated current, and also capable of downsizing the cleaner body. The purpose is to provide a machine.

(Means for Solving Problems) According to the present invention, an electric motor, a fan rotatably driven by the electric motor, and a fan provided in communication with the dust collecting chamber are provided in a cleaner body having the dust collecting chamber provided therein. An electric blower formed of a rectifying plate having a diffuser action and rectifying the air flow from the fan, and a switching element for controlling the rotation speed of the electric blower are provided, and the rectifying plate is formed of a material having high thermal conductivity, The switching element is closely attached and fixed to the rectifying plate.

Further, in the present invention, the switching element is provided at a position facing and close to one of the blowout holes formed in the rectifying plate.

(Operation) In the electric vacuum cleaner of the present invention, since the switching element is closely attached and fixed to the rectifying plate made of a material having a diffuser function of the electric blower and having high thermal conductivity, the rectifying plate is used as a heat radiating plate, so that the switching is performed. The heat generated from the element is quickly transferred to the rectifier plate, which has a large surface area and high thermal conductivity, and the total amount of intake air hits the rectifier plate. Since heat is taken away by the switching element and heat is efficiently dissipated from the switching element, it becomes possible to pass a larger current close to the maximum rating to the switching element,
It becomes possible to use an inexpensive switching element having a small maximum rated current, and it is not necessary to provide a storage space for a dedicated heat dissipation plate inside the cleaner body, and the cleaner body is downsized.

(Example) Hereinafter, the structure of one example of the vacuum cleaner of the present invention will be described with reference to the drawings.

The vacuum cleaner of this embodiment is a handy type small vacuum cleaner using a battery as a power source.

In FIGS. 1 to 3, reference numeral 11 denotes a cleaner body, and the cleaner body 11 is formed in a case shape, and a handle 12 is integrally provided on the upper rear side. The interior of the cleaner body 11 is divided into front and rear by a partition wall 14 having a communication port 13 formed therein, and a front side of the partition wall 14 is a dust collection chamber 15 in which a dust collection filter (not shown) is mounted. . Also,
A suction port 16 is provided at the front end of the cleaner body 11 facing the dust collecting chamber 15.
Is formed with an opening. Further, an exhaust port 17 is formed in the rear portion of both side surfaces of the cleaner body 11, for example.

Further, 31 is an electric blower, and this electric blower 31 is an electric blower.
32, a fan 33 that is rotationally driven by the electric motor 32, and a rectifying plate 21.

The current plate 21 is made of a material having a high thermal conductivity, such as metal such as aluminum, and is provided on the outer circumference of the disk portion 22 with a cylindrical portion 23.
And is fixed in the cleaner body 11 adjacent to the rear side of the communication port 13 of the partition wall 14. A cylindrical fitting portion 24 is formed so as to project at the center of the rear surface of the disc portion 22 of the current plate 21. Also, this rectifying plate
A plurality of blowout holes 25 are formed in the outer edge portion of the disc portion 22 of 21 and the rear surface of the disc portion 22 has a spiral curvilinear shape by a plurality of ribs 26 corresponding to the blowout holes 25. A flow path 27 is formed.

The front end of the electric motor 32 is fitted and fixed to the fitting portion 24 of the rectifying plate 21, and the fan 33 is attached to the rotating shaft of the electric motor 32 that penetrates the disc portion 22 of the rectifying plate 21 and projects forward. Is fixed, and the fan 33 is covered with the current plate 21 except the front surface. Further, the fan 33 is connected to the communication port 13 of the partition wall 14.
A front plate 35 having a nozzle-shaped opening 34 facing each other, a rear plate 36 parallel to the front plate 35, and a plurality of blades 37 radially provided between the front plate 35 and the rear plate 36. There is.

Further, on the rear surface of the rectifying plate 21, a three-terminal switching element 41 such as a transistor or a triac for controlling the rotation speed of the electric blower 31 is provided at a position facing and close to one outlet 25 of the rectifying plate 21 with a screw 42. It is fixed in close contact with. Further, the terminals of the three-terminal switching element 41 are connected to the connection board 44 from which the lead wire 43 is led out.

Further, a battery 46, which is a power source of the electric motor 32, is provided in the rear portion of the cleaner body 11, and a circuit board on which a control circuit for controlling the three-terminal switching element 41 is mounted, for example.
47 are provided. In addition, the handle of the cleaner body 11
On the front part of 12, there is an operator 48 for operating the electric blower 31.
Is provided.

Next, the configuration of the electric circuit for controlling the electric blower 31 of the above embodiment will be described with reference to FIG.

A transistor is used as the three-terminal switching element 41, the anode of the battery 46 is connected to the collector of this transistor, and one end of the electric motor 32 is connected to the emitter. The other end of the electric motor 32 is connected to the cathode of the battery 46. Furthermore, a series circuit including a resistor 51 and a variable resistor 52, which is a transistor control circuit, is connected in parallel between both electrodes of the battery 46.
The base of the transistor is connected to the slider of 52.

Then, by operating the variable resistor 52, the base voltage is changed, and the rotation speed of the electric motor 32 is changed.

Next, the operation of the above embodiment will be described.

When a current flows through the electric motor 32 via the three-terminal switching element 41, the fan 33 rotates to generate a suction force. In addition,
This suction force is generated by the 3-terminal switching element 41
It can be changed by controlling the rotation speed of 32. Then, the dust sucked from the suction port 16 together with the suction airflow is captured and stored by a dust collection filter (not shown) mounted in the dust collection chamber 15.

By the way, the current plate 21 has a diffuser action for improving the suction efficiency. That is, the airflow is a fan
After being sucked into the fan 33 from the opening 34 of the front plate 35, the air flows between the outer peripheries of the front plate and the rear plate 36, and then the current plate 21
After being blown out rearward from the blowout hole 25 at the outer edge of the
Is discharged to the outside of the cleaner body 11 through the exhaust port 17.

Further, during cleaning, the heat generated from the three-terminal switching element 41 has a large surface area and has a high thermal conductivity.
Promptly. At the same time, the air flow of the entire intake air flowing along the rectifying plate 21 rapidly cools the rectifying plate 21 and the three-terminal switching element 41 fixed to the rectifying plate 21, so that the heat dissipation effect of the three-terminal switching element 41 is improved. it can. Moreover, since the three-terminal switching element 41 is located facing and close to the blowout hole 25 of the rectifying plate 21, the blowout hole is formed.
A fast airflow that is throttled at 25 is a 3-terminal switching element
By strongly blowing on the 41, the heat dissipation effect of the three-terminal switching element 41 can be further improved.

Since the heat dissipation effect of the three-terminal switching element 41 is high in this way, a larger amount of current close to the maximum rating can be passed through the three-terminal switching element 41. Therefore, if the maximum current to be passed through the electric motor 32 is the same, a less expensive three-terminal switching element 41 having a smaller maximum rated current than the conventional one can be used.

Further, since the rectifying plate 21 is used as a heat radiating plate, the cost can be further reduced, and it is not necessary to provide a dedicated heat radiating plate storage space, and the cleaner body 11 can be made smaller.

(Effect of the invention) According to the electric vacuum cleaner of the present invention, the rectifying plate having a large surface area of the electric blower and having a high thermal conductivity is closely fixed to the switching element, and the rectifying plate is used as a heat radiating plate. The heat generated from the switching element is quickly transferred to the rectifier plate, and the total amount of intake air hits the rectifier plate, and the fast airflow passing through the rectifier plate quickly removes heat from the rectifier plate and the switching element, resulting in heat dissipation efficiency of the switching element. Can be improved, more current near the maximum rating can be applied to the switching element, and an inexpensive switching element with a smaller maximum rated current can be used. It is not necessary to provide the vacuum cleaner, and the vacuum cleaner body can be downsized.

[Brief description of drawings]

FIG. 1 is a partially cutaway side view showing an embodiment of an electric vacuum cleaner of the present invention, FIG. 2 is a perspective view of the vicinity of the current plate, and FIG.
The figure is a sectional view of the vicinity of the three-terminal switching element of the same as above, FIG. 4 is a circuit diagram of the same as above, and FIG. 5 is a partially cutaway side view showing an example of a conventional vacuum cleaner. 11 …… Vacuum cleaner body, 15 …… Dust collection chamber, 21 …… Rectifier plate, 25…
… Blowout hole, 31 …… electric blower, 41 …… 3-terminal switching element.

Claims (2)

[Claims] 1. A cleaner body having a dust collecting chamber provided therein, which communicates with the dust collecting chamber, rectifies an electric motor, a fan rotationally driven by the electric motor, and an air flow from the fan, and a diffuser. An electric blower including a rectifying plate having an action, and a switching element for controlling the rotation speed of the electric blower are provided, and the rectifying plate is formed of a material having high thermal conductivity, and the switching element is closely attached to the rectifying plate. An electric vacuum cleaner characterized by being fixed. 2. The electric vacuum cleaner according to claim 1, wherein the switching element is provided at a position facing and close to one of the blowout holes formed in the rectifying plate.