JPS6411840B2 - - Google Patents

Description

[Detailed description of the invention] (Field of application of the invention) This invention relates to a propeller for a fan motor.

(Prior art) Conventionally, when detecting the rotation of a fan motor with a propeller, it has been common to use a nearby light source, such as a strobe light sensor, to reflect the light from the rotating propeller. For this purpose, marks or stickers were pasted on the upper surface of the propeller.

Furthermore, when measuring or correcting the dynamic balance of a motor, the propeller and propeller assembly are used.

(Problems to be Solved by the Invention) When detecting rotation, the work of pasting marks or stickers to reflect the light source is cumbersome, and even if the dynamic balance is measured with the propeller assembled, the final finished product will not work properly. However, there were problems such as imbalance.

(Means for Solving the Problem) Therefore, in the present invention, a rotation detection mark based on light source reflection is finished integrally on the surface of the propeller itself using a mold, etc., and an identical mark is placed on the inside of the propeller using the rotation detection mark as a reference. A pitch angle display is provided, and by using the angle display, the unbalanced position can be easily corrected after the motor is assembled.

(Function) Therefore, it is not necessary to separately attach a rotation detection mark, rotation can be easily detected by light source reflection, and the dynamic balance of the propeller and propeller assembly can be corrected using the same pitch angle display. This can be done after the motor is assembled.

(Embodiment) In FIG. 1, a portion 10 of a front plate 8 of a propeller 2 having blades 6 attached to the outer periphery of a cylindrical body 4 is shown.
is given a mirror finish using a mold or the like, and the other front plate is given a pear finish 12. Reference numeral 14 denotes a rotating shaft that projects rearward from the front plate 8. The propeller 2 is usually made of synthetic resin or the like. Angular table lines 16 are formed on the inner surface of the cylindrical body 4 at equal intervals with respect to the mirror finished portion 10. Therefore, when detecting rotation, the light beam is reflected by the mirror-finished portion 10, but
It is not reflected on the satin finish portion 12. FIG. 2 illustrates an example of motor rotation detection. When the propeller 2 is rotated by the rotation shaft 14, a beam from a light source, for example, a reflective optical sensor 18 provided close to the front plate 8 of the propeller 2 is emitted onto the mirror-finished portion 10 of the front plate 8.
It reflects and generates a pulse. As shown in FIG. 3, the generated pulse waves 20 are generated once every rotation of the propeller at equal intervals.

Next, in order to measure the amplitude of vibration during rotation of the fan motor 22 to which the propeller 2 is attached, a vibration pickup 24 is used as shown in FIG. The output waveform 26 measured by the vibration pickup 24 is as shown in FIG. The cause of this waveform is thought to be due to imbalance during propeller assembly.

Therefore, when the pulse waveform 20 shown in FIG. 3 is adjusted on the screen into six divisions, one division becomes 60 degrees. When this is synchronized with the vibration waveform 26, a composite waveform as shown in FIG. 6 is obtained. In FIG. 6, A is the peak position of the vibration waveform 26, that is, the unbalanced position of the motor, and B is the pulse wave reference setting position, that is, the position of the mirror finish portion 12. Now, if the difference between A and B is read on the screen and is divided into 1/2, the angular difference between the unbalanced position of the motor and the mirror-finished part of the propeller is 30 degrees. Of course, the composite waveform illustrated in FIG. 6 is merely an example for explanation. It goes without saying that the unbalanced position exists at various angles from the mirror finished portion 10 depending on various circumstances.

As explained above, when the angular difference in the unbalanced position of the motor is determined, the body 4
Using the angle display lines 16 arranged at equal intervals on the inside of the mirror-finished part 10, the unbalanced position relative to the mirror-finished part 10 can be confirmed, and the unbalance can be corrected. The methods are (a) if the unbalance is small, correct it by adding a plumb or the like to that position of the propeller (angular difference position); or (b) if the unbalance is large, correct it. , by removing the mass of the portion of the propeller corresponding to the angle difference between the predetermined angle display lines by cutting or the like.

(Effects) In the present invention, a mirror-finished part for reflecting light is provided on the front plate of the propeller body, making it unnecessary to attach another reflective member such as a sticker, and furthermore, the mirror-finished part on the inner surface of the propeller body is used as a reference. By arranging angle display lines at equal intervals and actually determining the unbalanced position of the motor on the angle display lines based on the angle difference on the screen between the pulse wave caused by light reflection and the vibration wave caused by vibration, it is possible to easily determine the unbalanced position of the motor on the angle display line after propeller assembly is completed. This makes it easy to correct motor imbalance.

[Brief explanation of the drawing]

FIG. 1a is a perspective view of a propeller according to the present invention, seen from the front. Figure b is a perspective view seen from the rear. FIG. 2 is a schematic side view of the arrangement of optical sensors. FIG. 3 is a schematic diagram of pulses due to light reflection. FIG. 4 is a diagram showing vibration waveforms. Figure 5 is a partial sectional view of a fan motor equipped with a vibrating pickup. FIG. 6 is a composite waveform diagram showing the angular difference between a pulse wave and a vibration wave. 2...Propeller, 4...Body, 8...Front plate, 10...Mirror finish section, 12...Pearl finish section, 16...Angle display line, 18...Photo sensor,
20...Pulse wave, 22...Fan motor, 26
...Vibration waveform.

Claims (1)

[Claims] 1. The part of the front surface of the propeller that reflects the beam is formed into a mirror-finished part, and the other part is formed into a non-reflective part, and angle indicators are provided at the same intervals on the inside of the body with reference to the mirror-finished part. A fan motor propeller featuring: 2. A propeller for a fan motor according to claim 1, which has a propeller made of synthetic resin. 3. A propeller for a fan motor according to claim 1, which is provided with an angle display that makes it possible to confirm an unbalanced position of the motor based on the angular difference between the pulse wave and the vibration wave. 4. A propeller for a fan motor according to claim 1, which has a front portion having a satin finish except for the mirror finished portion.