GB2093525A

GB2093525A - Apparatus for adjusting the oscillatory movement of an electric fan

Info

Publication number: GB2093525A
Application number: GB8105221A
Authority: GB
Original assignee: YI HSIN HUANG
Current assignee: YI HSIN HUANG
Priority date: 1981-02-19
Filing date: 1981-02-19
Publication date: 1982-09-02

Abstract

The apparatus includes a main shaft (1) driven by an electric motor, a worm gear (2) coupled with the main shaft (1), a member (6) having a bevel-gear (5) connected thereto, a shaft (11) with a bevel gear on one end, and a movable pivot (8) screwed on the shaft (11). The rotation of the member (6) by a shaft (3) causes the pivot (8) to rotate a gear (15) via a link (13), thereby rotating a gear (20). Also, the rotation of the bevel gears rotates the shaft (11) to adjust the position of the pivot (8) with respect to its rotational axis formed by the shaft (3), thereby varying the angular swing of the electric fan. <IMAGE>

Description

SPECIFICATION Adjustable apparatus for controlling the swing direction of electric fan This invention relates to an adjustable apparatus for controlling the swing direction of electric fan in virtue of the mechanical structure of four-bar linkage and epicyclic train. By varying the distance of the axial centre line between a movable pivot and a driving shaft of this invention, the swing direction of the electric fan can be regulated ranging from 0 -360 as desired.

Conventionally, the swing direction of an electric fan is usually arranged in a fixed pattern such as those of table-type and erecting-type, or as that of the suspension-type which can only make a fixed circumferential rotation. Therefore, the known electric fan is very inconvenient in making any adjustment for the swing direction, and the working efficiency is not fully developed therewith.

The present invention provides a novel and improved adjustable apparatus for controlling the swing direction of electric fan in a desired range.

It is a primary object of the invention to provide an adjustable apparatus for controlling the swing direction of electric fan ranging from 0 to 1800 and 360" as desired.

It is another object of the invention to provide an adjustable apparatus for controlling the swing direction of electric fan as to facilitate the usage, minimizing unnecessary cost, and promoting the utility of electric fans.

With objects in view, the structure of this invention is actuated by a motor through a motor main shaft having worm effect, and, with a variation of the axial direction and rotating speed effected through a worm gear coupled with the main shaft, a swing governor seat connected thereto follows the rotation of the main shaft making a movable pivot coupled with it move left and right therein. As a result, the eccentric position existing between the movable pivot and a driven gear creats a rocking-bar motion and causes the driven gear connected therewith to rotate. As the driven gear is also meshed with a fixed gear, the rotation of the driven gear will drive the fixed gear in epicycle movement; thereby, a circumferential swing of the electric fan is achieved.

Specifically, by varying the position of the movable pivot relative to the swing governor seat, the swing direction of the electric fan can be adjusted in any desired range.

To assist in a better understanding of the invention this will be described with reference to the accompanying drawings in which: Figure 1 is an exploded and perspective view of an adjustable apparatus of this invention for controlling the swing direction of electric fan, Figure 2 is a cross-sectional view of an adjustable apparatus of this invention in combination, and Figure 3 is a schematic illustration showing the operational structure of the four-bar linkage of the adjustable apparatus of this invention for controlling the swing direction of electric fan.

Referring to Fig. 1 and 2, an adjustable apparatus of this invention comprises a main shaft 1 having a worm effect being directly connected to a spindle of an electric-fan motor (as shown with dotted line in Fig. 2); a worm gear 2 meshed with the worm portion of the main shaft 1 and fixed together with a spur gear round a driving shaft 3 which is secured, through a bevel-gear adjusting disc, to a swing governor seat 6 by a cotter bolt 4 on the lower portion of the driving shaft 3.The swing governor seat 6 having a recess 7 on one side, a regulating shaft 11 with a bevel gear at one end, two openings 9 and 10 on both sides, and a movable pivot 8 with an adjusting screw hole 12, are combined in such a way that when the regulating shaft 11 is driven to turn through the engagement with the bevel-gear adjusting disc 5, the movable pivot 8 screwed round the regulating shaft 11 through the adjusting screw hole 12 will move left and right in the recess 7 along the regulating shaft 11. A link 13 is coupled with the movable pivot 8 at one end and secured to a screw hole 16 on a driven gear 15 at another end by a screw bolt 14.The driven gear 15 is connected to the motor casing 18through a driven shaft 17 having male threads on its upper portion, secured therein by a locking screw 19 so as to be fixed in position, and meshed with a fixed gear 20 which is mounted on a strut 21. The pitch diameter of the driven gear 15 is equal to that of the fixed gear 20, and the distance between the axial centre lines of the two gears 15 and 20 is equal to the sum of the pitch radius of the two gears 15 and 20 so that the two gears are always kept in well meshed state. The motor casing 18 is also connected to an axle opening 23 of the fixed gear 20 through a thrust bearing 22 for rotating operations thereat.

Referring to Fig. 1 and 2, this invention is actuated to work through a control box (not shown) for supplying power to the motor which when turns, the motor power will, through the main shaft 1 with worm effect, reduce its speed and change its axial direction for driving the driving shaft 3 which in turn moves the bevel-gear adjusting disc 5 and rotates the regulating shaft 11 engaged therewith round the axial line of the driving shaft 3, so that the movable pivot 8 screwed round the regulating shaft 11 will be moved left and right in the recess 7. Furthermore, the movable pivotS, the screw bolt 14, the driven shaft 17 of the driven gear 15, and the motor casing 18 constitute a four-bar linkage thereof.Under the influence and control of the distance between the movable pivot 8 and the driving shaft 3, a different swing amplitudes are provided by the driven gear 15 accordingly.

The changeable distance between the movable pivot 8 and the driving shaft 3 is the most significant factor required for regulating the swing angle of this invention. As a bevel-gear adjusting disc 5 is meshes with the bevel gear of the regulating shaft 11, any rotation made by the bevel-gear adjusting disc 5 will cause the regulating shaft 11 to turn. On the other hand, as the regulating shaft 11 is screwed with the movable pivot 8, whenever the regulating shaft 11 turns, the non-rotatable pivot 8 will only move left and right along the regulating shaft 11 in the recess 7, thus the swing direction control of the electric fan is achieved.

Concerning the academic appiication of this invention explanation is made with reference to Fig. 3 which is a graphic illustration of the four-bar linkage operation of this adjustable apparatus.

As shown in Fig. 3, O, is the centre of the driven shaft, and 02 is the driven shaft while D is the distance between the two shafts. The eccentric position C1 of the link connected to the driven shaft and the axial centre O, constitute a rocker thereat with a fixed distance between C1 and O,. But, asto the other end of the lind and the position of the movable pivot C2, the distance between the connecting point C2 and the axial centre 02 is of a variable.

In the above configuration, when C, "C2 " 2 = D + R2, the LC," O. 02 is the largest and designated as L(p.

When C, ' 2 = D - R2, the LC,'O,O2 is the smallest and designated as LO.

If D = O, 2, according to the law of cosine: cos(p = R,2 + - (D + R2)2/2R,D = R1 - R22 - 2DR2/2R1D = R12 - R2212R1D - R2IR1 cos fl = R,2 + D2 - (D - R2)2/2R1D = R12- R22+ 2DR2/2R1D = R12- R22I2R1D + R2/R1 Concluding from cos (p and cos fl, and R1 h 0: a) when R, = R2, cos ç = -R2/R, = -1, the ç = 1 80 ; cos fl = R2/R, = 1,the 8 = 0 ; therefore, cp - 8 = 180" - 0" = 180"; and b) when R2 = 0, cos (p = Rt2/2R,D = R112D i.e.

cos (p = cos fl = R,/2D; cos fl = R:/2R,D = R,/2D i.e.

(p = B,.-. ç - 8 = 0.

As above expressed, when R, = R2, the turning angle of the driven gear is 1809 and, as a result of its inertia effect, the driven shaft rotates in 360" following the movement of the swing governor so that the direction of the electric fan also rotates in 360".

When R2 = 0, the driven gear is in stationary condition, and the direction of the electric fan remains no change. Since R2 is the variable from R, to 0, the swing angle of the electric fan can be adjusted to any desired direction.

While a preferred embodiment has been illustrated and described, it will be apparent that many changes may be made in the general construction and arragement of the invention without departing from the spirit thereof, and it is therefore desired that the invention be not limited to the exact disclosure but only to the extent of the appending claims.

Claims

CLAIMS 1. An adjustable apparatus for controlling the swing direction of an electric fan comprising: a) a motor main shaft having worm effect; b) a worm gear meshed with a worm portion of said main shaft and secured round a driving shaft; c) a bevel-gear adjusting disc attached to said driving shaft; d) a swing governor seat having a recess on one side, a regulating shaft with a bevel gear at one end, an opening for receiving said regulating shaft, and a movable pivot with an adjusting screw hole for coupling with said regulating shaft, being connected to said driving shaftthrough said bevel-gear adjusting disc; e) a link coupled with said movable pivot at one end; f) a driven gear matched with a driven shaft, connected to said link at another end, and secured to a motor casing; and g) a fixed gear mounted on a strut, connected to said motor casing through a thrust bearing, and meshed with said driven gear, whereby a desired swing direction control can be achieved with the combination thereof. 2. An adjustable apparatus for controlling the swing direction of an electric fan as claimed in Claim 1 wherein the swing direction control is made by means of varying the position of said movable pivot. 3. An adjusting apparatus for controlling the swing direction of an electric fan as claimed in Claims 1 or 2 wherein said movable pivot is coupled with said regulating shaft in threads so that when said regulating shaft rotates, said movable pivot will not make any turn but moves back and forth instead along said regulating shaft, thereby making the distance between said movable pivot and said driving shaft changeable therein. 4. An adjustable apparatus for controlling the swing direction of an electric fan as claimed in Claim 1 wherein the combination of said swing governor seat, said link, said driven gear, and said motor casing constitutes a four-bar linkage thereof. 5. An adjustable apparatus for controlling the swing direction of an electric fan as claimed in Claim 4 wherein, as the distance between said movable pivot and said driving shaft being a variable while the distance between said driven gear and said driven shaft as well as said motor casing being nonvariable in dimensions, the movement made by said movable pivot can effectively regulate the swing direction of an electric fan ranging from 0 to 1800 and 360 as desired. 6. An adjustable apparatus for controlling the swing direction of an electric fan as claimed in Claim 1 wherein, as the pitch diameter of said driven gear being equal to that of said fixed gear, and the distance between the axial centre lines of said driven gear and said fixed gear being equal to the sum of the pitch radius ofsaid driven gear and said fixed gear, said driven gear and said fixed gear therefore constitute an epicyclic train therein. 7. An adjustable apparatus for controlling the swing direction of an electric fan, constructed and arranged substantially as hereinafter described with reference to and shown in the accompanying drawings. New claims or amendments to claims filed on 1912182. Superseded claims 1 to 7. New or amended claims: CLAIMS

1. Apparatus for selectively varying the degree of swing of an oscillatable fan comprising: a shaft adapted to be driven from a motor of the fan, a member rotatable on a longitudinal axis of the shaft and driven by the shaft, an apicyclictrain device including a first member fixed relative to a stationary support of the fan and a second member adapted to move epicyclically of the fixed member, and a link mechanism connecting the rotatable member and the said second member for moving the said second member epicyclically of the fixed member when drive is transmitted by the shaft, the link mechanism being connected to the rotatable member by a pivot selectively movable in an axial direction of the shaft.

so that, by selectively varying the distance between the movable pivot and the said axis of the shaft, an axis of rotation of the fan is constrained to move selectively in a curved path in the range 0"- 360 relative to a central longitudinal axis of the said fixed member.

2. Apparatus as claimed in Claim 1 wherein the movable pivot comprises a screw member carried by the rotatable member and rotatable on a longitudinal axis thereof relative to the rotatable member and a travelling member adapted to combine with the screw member so that when the screw member rotates relative to the rotatable member, the travelling member moves longitudinally of the screw member.

3. Apparatus as claimed in Claim 2 wherein means is provided for rotating the screw member.

4. Apparatus as claimed in Claim 3 wheirein the means for rotating the screw member includes gears in engagement one with another.

5. Apparatus as claimed in Claim 4 wherein the gears are bevel gears.

6. Apparatus as claimed in Claim 5 wherein one of said gears is arranged such that a central longitudinal axis thereof is co-axial with said shaft.

7. Apparatus as claimed in any one of the preceding claims wherein the rotatable member, the link mechanism, the said second member of the epicyclic train device and the said stationary support in combination comprise a four-bar linkage.

8. Apparatus as claimed in any one of the preceding claims wherein the said first member and the said second member of the epicyclic train device comprise respectively a first spur gear and a second spur gear, the pitch diameter of the spur gears being equal and the distance between the axis of rotation of the rotatable spur gear and the centre of the fixed spur gear is equal to the sum of the pitch radius of the rotatable spur gear and the fixed spur gear so that the rotable spur gear and the fixed spur gear constitute an epicyclictrain.

9. Apparatus for selectively varying the degree of swing of an oscillatable fan constructed and arranged substantially as herein described with reference to and as illustrated in the accompanying drawings.