JPH0332909Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a shutter opening/closing device for a ventilation fan that opens and closes the shutter electrically.

A conventional shutter opening/closing device is shown in FIGS. 1 to 3. Figure 1 is a schematic circuit diagram, in which 1 is a fan motor, 2 is a synchronous motor, 3 is a DC electromagnetic plunger that energizes the clutch of synchronous motor 2, 4 is a full-wave rectifier, and 5 is a synchronous motor. This is a micro switch that opens and closes the energizing circuit to the motor 2.

2 and 3 are schematic structural diagrams of the entire ventilation fan. In each figure, 6 is a shutter, which is supported by a pin 7 on the main body 8 of the ventilation fan, and a drive arm 9 at one end.
is provided. This drive arm has a return spring 10.
and one end of the wire 11 are respectively hooked. The other end of the return spring 10 is hooked onto the main body 8 to apply tension to the drive arm 9. 12 is the main body 8
The shutter opening/closing mechanism is fixed to the 1
3 is a clutch actuator of the synchronous motor 2, 14 is the output shaft thereof, 15 is a wire take-up pulley fixed to the output shaft 14, a cam 16 is integrally provided, and the wire 11 is attached. It is being 17 is a retaining ring that fixes the wire take-up pulley 15 to the output shaft 14;
18 is an operating lever for opening and closing the contacts of the micro switch 5; 19 is a plunger pin of the DC electromagnetic plunger 3;
The clutch actuator 13 is provided opposite to the clutch actuator 13 of the clutch actuator 13.

The conventional device is configured as described above, and when the power is turned on, the fan motor 1 rotates, and at the same time, the DC electromagnetic plunger 3 also operates, pushing out the plunger pin 19 and engaging the clutch actuator 13 of the synchronous motor 2. energize. On the other hand, the micro switch 5 is closed and the synchronous motor 2 also rotates. As a result, the wire take-up pulley 15 rotates to wind up the wire 11 and the shutter 6 begins to open as shown by the arrow in FIG. In this way, the wire take-up pulley 15 rotates, and when the cam 16 presses the operating lever 18 of the micro switch 5, the micro switch 5
is opened and the synchronous motor 2 stops.
In other words, the opening operation of the shutter 6 has been completed. Next, when the power is turned off, the fan motor 1 stops, and at the same time, the electricity to the DC electromagnetic plunger 3 also stops, so the clutch actuator 13 of the synchronous motor 2 is also deenergized, and the tension of the return spring 10 causes the wire to be wound. The pulley 15 reverses and returns to close the shutter 6. Further, the operating lever 18 of the micro switch 5 is also pressed, and the micro switch 5 is closed.

In the above operation, when the power is turned on, the wire take-up pulley 15 rotates, and the micro switch 5 is opened by the cam 16, the synchronous motor 2 stops, but immediately after this stop, it rotates slightly in reverse.
This is due to the rotational play of the reversal prevention mechanism inside the synchronous motor 2. Due to this reversal, the operating lever 18 of the micro switch 5 may also return slightly and the micro switch 5 may be closed again, so that the synchronous motor 2 starts rotating again and rotates until the micro switch 5 is opened. Thereafter, this operation will be repeated, that is, chattering will occur. However, since the microswitch 5 generally has a hysteresis movement, it is sufficient to use a switch with a large hysteresis movement. However, variations in the movement of the hysteresis may cause chattering, and furthermore, it is generally difficult to manage the movement of the hysteresis so that it becomes larger than a certain value. Conventional devices had the above-mentioned drawbacks.

This idea was made with the aim of improving the drawbacks of the conventional device as described above.The cam was rotatably provided separately from the wire take-up pulley, and the cam had an angle that limited the rotation of the synchronous motor. By providing an interlocking means for receiving and interlocking rotation between the cams and a spring that is formed integrally with the cam in a substantially arc shape and that provides resistance against the rotation of the cam, it is independent of the hysteresis movement of the switch. To provide a shutter opening/closing device for a ventilation fan that does not generate chattering.

An embodiment of this invention will be described below.

FIGS. 4 and 5 are schematic diagrams showing an embodiment of this invention. In the figure, the cam 21 is rotatably provided on the output shaft 14 of the synchronous motor 2. A wire take-up pulley 22 is separate from the cam 21 and is fixed to the output shaft 14.
The cam 21 is provided with interlocking pawls 23 and 24 as interlocking means for winding up and returning, while the wire take-up pulley 22 is provided with a cam drive pawl 25. 26 is a substantially arc-shaped spring provided integrally with the cam 21, and 27 is a spring pressing pin provided in the shutter opening/closing mechanism 12. The structure other than this is the same as the conventional device described above, and the explanation will be omitted.

In the apparatus configured as described above, when the power is turned on, the wire take-up pulley 22 rotates and the shutter 6 begins to open. At this time, the cams 21 do not start rotating at the same time, but the wire take-up pulley 22 rotates and the cam drive claw 25 moves the winding interlocking claw 2 of the cam 21.
When the rotation reaches position 3, the cam 21 and the wire take-up pulley 22 start to rotate in conjunction with each other due to the contact between the driving claw 25 and the interlocking claw 23 for winding, and the cam 21 starts rotating when the micro switch 5 is operated. Since the lever 18 is pressed, the micro switch 5 is opened,
The synchronous motor 2 stops. At this time, a resistance force against rotation is applied to the cam 21 by the spring 26 and the spring pressing pin 27, but the synchronous motor 2 overcomes this force and rotates. Next, when the power is turned off, the wire take-up pulley 22 is reversed by the return spring 10, and the shutter 6 begins to close. At this time, since the cam 21 is given a resistance force against rotation by the spring 26 and the spring pressing pin 27, it does not start reversing at the same time, but the wire take-up pulley 22 reverses and the cam drive claw 25 rotates against the cam 21. When the reverse rotation reaches the return interlocking pawl 24 of 21, the reverse rotation is started for the first time, the operating lever 18 of the micro switch 5 is deenergized, and the micro switch 5 is closed.

As is clear from the above configuration and operation, the power is turned on, the wire take-up pulley 22 rotates, and the cam 2
1, the micro switch 5 is opened and the synchronous motor 2 is stopped immediately or even if it is slightly reversed, the micro switch 5 will not close again regardless of the hysteresis movement, and no chattering will occur.

As explained above, this invention has the advantage that since the spring is formed integrally with the cam, a separate component is not required as the spring, the number of components can be reduced, and costs can be reduced.

[Brief explanation of the drawing]

Fig. 1 is a schematic circuit diagram of a conventional device, Fig. 2 is a schematic structural diagram of a conventional device, Fig. 3 is a sectional view taken along line A-A in Fig. 2, and Fig. 4 is a schematic diagram showing an embodiment of this invention. The structural diagram, FIG. 5, is a sectional view taken along the line B--B in FIG. 4. In the figure, 2 is a synchronous motor with a clutch, 3 is a DC electromagnetic plunger (clutch energizing means), 5 is a switch, 6 is a shutter, 8 is the main body of the ventilation fan, 11 is a wire, 12 is a shutter opening/closing mechanism, and 13 is a synchronizer. Clutch actuator of the eggplant motor, 14 is an output shaft, 18 is a switch operation lever, 21 is a cam, 22 is a wire take-up pulley, 23 and 24 are interlocking pawls (interlocking means),
26 is a spring (biasing means). In each figure, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Scope of utility model registration request] The synchronous motor is equipped with a synchronous motor with a clutch for opening and closing the shutter of the ventilation fan, a biasing means for the clutch, a switch for opening and closing energization of the synchronous motor, and a cam mechanism for biasing the operating lever of the switch. A wire take-up pulley is fixed to the output shaft of the motor, a cam for energizing the operating lever for opening and closing the switch is rotatably provided on the output shaft of the synchronous motor, and the cam is provided with a limit to the rotation of the synchronous motor. In the ventilation fan shutter opening/closing mechanism provided with an interlocking means for interlockingly rotating the cam itself by receiving the cam between the angles, the cam is formed integrally with the cam in a substantially arc shape,
A ventilating fan shutter opening/closing device characterized in that a spring is provided which generates a pressing force with a pressing pin provided near the cam and provides a resistance force due to the pressing force against the rotation of the cam.