JPS5819358Y2 - Blower blade mounting device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a blower blade mounting device that fixes a blower blade by engaging and holding a drive pin of a drive shaft in a retaining groove provided in a shaft insertion portion.

Conventionally, for example, in the case of a blower blade for an electric fan, a substantially cylindrical metal snub is embedded in the center of a plastic fan boss by insert molding, and a retaining groove is provided at one end of the sleeve. A spinner nut screwed into the tip of the sleeve is brought into contact with the other end of the sleeve, so that the retaining groove is pressed into engagement with a drive pin protruding from the drive shaft.

However, since such a conventional structure uses a metal sleeve, molding of plastic is troublesome and costs are high.

The present invention has been made in view of the above circumstances, and includes a shaft insertion portion having a retaining groove in which the base end of the drive pin is engaged, which is provided on the fan boss by integral molding of plastic, and further includes a A reinforcing rib having a support surface continuous with the engagement groove is provided by integral molding of plastic, and the support surface of the reinforcing rib supports substantially the entire length of the drive pin except for the tip. There is no need to provide a sleeve for the body, and the cost can be reduced because plastic can be easily molded.Although it is integrally molded from plastic, it can sufficiently resist the clamping force of the mounting body. The purpose is to provide equipment.

An embodiment in which the present invention is applied to an electric fan will be described below with reference to the drawings.

Reference numeral 1 denotes a base on which a support column 1a is erected, and 2 a fan head supported at the upper end of the support support 1a through a neck piece 3 so as to be able to swing freely, and a motor (not shown) for driving the blades is installed inside. has been done.

Reference numeral 4 denotes a blower blade fixed to a rotating shaft 5 of a motor as a drive shaft as will be described later, and 6 a guard that covers the blower blade 4.

Now, to explain the blower blade 4 in detail, 7 is a bottomed cylindrical fan boss with four blower blades 8 protruding from the outer periphery. A cylindrical shaft insertion portion 10 is formed by integral molding of plastic.

Reference numeral 11 indicates four approximately U-shaped engagement grooves formed at 90° intervals at one end of the shaft insertion portion 10, that is, the end opposite to the fan head 3; Four reinforcing ribs are provided on the inner surface of the fan boss 7 in a radial pattern centered on the shaft insertion portion 10 so as to be continuous with each engagement groove 11, and the tip of the reinforcing rib 12 is inserted through the four reinforcing ribs. The support surface 12a is perpendicular to the hole 9 and located on the same horizontal plane as the bottom surface of the engagement groove 11.

Reference numeral 13.13 denotes an inclined guide surface formed in a chevron shape oriented in the direction of the engaging grooves 11, 11 from approximately the middle part of the adjacent engaging grooves 11. It is provided.

Reference numeral 14 denotes a drive pin that is press-fitted into an insertion hole 5a provided in the rotating shaft 5, and has both ends protruding from the outer circumferential surface of the rotating shaft 5 by about 2.5 times the thickness of the shaft insertion portion 10, respectively.

Reference numeral 15 denotes a plastic spinner nut as a mounting body, which has a boss 15a protruding from the center and a side hole 1.
A metal fastening body 16 having a diameter of 6 a is insert-molded, and a screw hole 16 a is screwed into a screw portion 5 b formed at the tip of the rotating shaft 5 .

Then, the rotating shaft 5 is inserted into the insertion hole 9 of the shaft insertion part 10, the drive pin 13 is aligned with the engagement groove 11, and the screw hole 16a of the tightening body 16 is screwed into the threaded part 5b of the rotating shaft 5. When inserted, the shaft insertion part 10 is pressed in the direction of the drive pin 14 by the tightening body 16, and the base end of the drive pin 14 is engaged and held in the engagement groove 11, and the base end of the drive pin 14 is excluded. The receiver is supported by contacting the support surface 12 a of the reinforcing rib 12 over substantially its entire length, thereby fixing the blower blade 4 to the rotating shaft 5 .

As described above, according to this embodiment, unlike the conventional structure, there is no need to provide a separate metal sleeve, and moreover, it is sufficient to simply integrally mold plastic, so that manufacturing costs can be reduced significantly.

Further, the base end of the drive pin 14 is engaged with and held in the engagement groove 11, and approximately the entire length of the drive pin 14 excluding the base end is supported by the support surface 12a of the reinforcing rib 12 which also serves to reinforce the fan boss 7.
Since the receiver is supported by the fan boss 7, the clamping force from the clamping body 16 can be supported by the wide area of the fan boss 7. Therefore, the fan boss 7 is made of integrally molded plastic and has relatively weak strength. However, the fan boss 7 is the tightening body 1.
It can withstand the clamping force of 6 without cracking.

Furthermore, since the drive pin 14 contacts the engagement groove 11 and the support surface 12a of the reinforcing rib 12, the receiver is supported over a wide area.
The fan boss 7 can be molded to have a thin and uniform wall thickness, the dimensional accuracy will not deteriorate due to molding marks, etc., and the gap between the insertion hole 9 and the rotating shaft 5 can be minimized. .

Therefore, the blower blade 4 can be attached to the rotating shaft 5 without any play.

In addition, in the conventional structure, if the metal sleeve was not sufficiently oil-removed after cutting, the plastic blower blades would crack due to oil, but in this example, a metal sleeve is required. Because it doesn't do that, the blower blades won't break.

Further, although the above embodiment has been described as being applied to an electric fan, it can also be applied to the blowing blades of various types of blowers other than electric fans, and the mounting body may be constructed so that the blowing blade 4 is biased in the axial direction by a spring. .

As explained above, the present invention allows the blower blade to be easily manufactured by integral molding of plastic without the need for a metal sleeve, resulting in lower costs, and even though it is made of plastic, the clamping force of the mounting body can be reduced. It is possible to provide a mounting device for a blower vane that can sufficiently withstand.

[Brief explanation of the drawing]

The drawings show an embodiment in which the present invention is applied to an electric fan, in which Fig. 1 is a schematic side view, Fig. 2 is an enlarged vertical sectional view of the main part, and Fig. 3 is an enlarged perspective view of the main part. It is. In the drawing, 4 is a blower blade, 5 is a rotating shaft (drive shaft), 7 is a fan boss, 8 is a blade, 10 is a shaft insertion part, 11 is an engagement groove,
12 is a reinforcing rib, 12a is a support surface, 13 is a drive pin,
15 is a spinner nut (attachment body), and 16 is a tightening body.

Claims (1)

[Scope of utility model registration request] A fan boss includes a cylindrical shaft insertion portion formed by integral molding of plastic, with a plurality of air blowing blades protruding from the outer periphery and a drive shaft inserted through the center portion, and a fan boss provided at one end of the shaft insertion portion. a retaining groove in which a base end of a drive pin protrudingly provided on the drive shaft is engaged; and a base end of the drive pin provided integrally with the fan boss by integral molding of plastic so as to be continuous with the retaining groove. A reinforcing rib having a supporting surface that supports substantially the entire length of the receiver except for a portion thereof, and a reinforcing rib that presses the fan boss toward the drive pin to engage the drive pin in the retaining groove and supports the receiver on the support surface. A mounting device for a blower blade, comprising a mounting body for fixing the blade.