US2746673A

US2746673A - Oscillating and like mechanism for electric fans

Info

Publication number: US2746673A
Application number: US464450A
Authority: US
Inventors: Collins Aubrey Lawrence
Original assignee: Individual
Current assignee: Individual
Priority date: 1954-10-25
Filing date: 1954-10-25
Publication date: 1956-05-22
Anticipated expiration: 1973-05-22

Description

A. COLLINS May 22, 1956 OSCILLATING AND LIKE MECHANISM FOR ELECTRIC FANS Filed Oct. 25, 1954 4 Sheets-Sheet 1 A4 ATTORNEY May 22, 1956 A. L. COLLINS OSCILLATING AND LIKE MECHANISM FOR ELECTRIC FANS Filed Oct. 25, 1954 4 Sheets-Sheet 2 mamm l A; ATTORNEYS May 22, 1956 OSCILLATING Filed Oct. 25, 1954 COLLINS 4 Sheets-Sheet 3 aha f i 102 as 57a 37a 59a 101 4 93 J 0 9 56a K4 ATTORNEY A. L. COLLINS May 22, 1956 OSCILLATING AND LIKE MECHANISM FOR ELECTRIC FANS Filed Oct. 25; 1954 4 Sheets-Sheet. 4

9 INVENTOR BY n,

2%, M M 1:47 ATTORNEYS United States Patent OSCILLATING AND LIKE lVIECHANISM FOR ELECTRIC FANS Aubrey Lawrence Collins, Harrow, England Application October 25, 1954, Serial No. 464,450

8 Claims. (Cl. 230-256) This invention relates to oscillating and like mechanism for electric fans and it has for an object to provide a form and construction of mechanism which is very convenient to operate and is simple to manufacture.

It is now well known to arrange for the electric driving motor and fan rotor to be mounted so as to oscillate or rotate bodily (herein referred to generically as turning) in order that the currents of air produced by the fan may be distributed in space instead of being confined to a stationary beam. Usually the turning can be initiated or stopped at will by manipulation of a control means but in the known arrangements this control means is closely associated with the motor and is therefore disposed upon that portion of the fan which turns, so that if it is to be manipulated easily and safely it is usually necessary first to switch off the fan before putting the turning mechanism into or out of operation. By the present invention this inconvenience can easily be overcome, and moreover the improved fan may readily be adapted for remote control by cords or other means operable while the fan is running. In the present specification the term base is intended to include any part of the structure which remains stationary while the head is turning.

In an electric fan comprising a base, a head which includes an electric motor and fan rotor and which is mounted with freedom to turn relative to said base, and turning mechanism driven by said motor so as to be operative between the head and the base, according to the invention a control member, which mechanically controls the operation of the turning mechanism, is mounted on the base and remains stationary when the head is turning.

According to another aspect of the invention an electric fan is provided comprising a base, a head which includes an electric motor and fan rotor and which is mounted with freedom to turn relative to said base, and turning mechanism driven by said motor so as to be operative between the head and the base, wherein the turning mechanism includes an anchorage member, a brake device adapted to hold the anchorage member against turning relative to the base, and a control member which is disposed upon the base and is adapted to bring the brake device into and out of action to control the turning of the head.

Moreover in an electric fan having its electric motor and fan rotor mounted pivotally upon a base so as to form a head arranged to turn and also having turning mechanism driven by said motor, according to another aspect of the invention the turning mechanism comprises an anchorage member movable relative to the base, a brake device for arresting movement of said anchorage member and thereby rendering the turning mechanism operative, and a control device mounted on said base so as to be free of the turning movement of said head.

Preferably a locking device is provided which is operative between the base and the head to hold the latter against turning, the control member for the brake device conveniently also operating the locking device, one being 'released while the other is applied. The brake device ice may have a non-positive holding action which can be overcome by the force of the turning mechanism if turning movement of the head is obstructed; also the locking device may have a non-positive holding action, which can be overcome by turning the head manually.

A turning mechanism suitable for oscillating the head may comprise a crank driven continuously by the motor and a connecting rod connecting the crank to the anchorage member. The brake device operable between the body and the anchorage member may comprise a nonpositive locating means such as a spring-pressed ball or other resilient catch member on one element adapted to co-operate with one or more recesses in the surface of the other element. If desired a locking device for checking turning of the head relative to the base may be arranged on the same principle. Moreover the control meansmay be in the nature of a change-over device adapted to throw either the brake device or the locking device into action at will, the other being rendered inoperative.

The invention is illustrated by way of example in the accompanying diagrammatic drawings, in which:

Figure 1 is a side elevation of the table fan, the controlling means for the turning action being shown in section;

Figure 2 is a fragmentary sectional plan taken on the line 2-2 of Figure 1 and showing the braking member;

Figure 3 is a sectional elevation of a modified construction of fan mounting, this being particularly suitable where the head is required to turn continuously;

Figure 4is a fragmentary sectional elevation of a further construction of mounting;

Figure 5 is a similar view of yet another embodiment of the invention; and

Figure 6 is a similar view of another arrangement.

The table fan shown in Figure 1 has a base 10 upon which a head is mounted, said head being indicated generally at 11 and being in the form of a guard cage, one of the main structural members of which is shown at 12. The head also includes an electric driving motor 13, on the spindle 14 of which a fan rotor 15 is fitted, the blades of the fan being shown at 16. The head 11 is arranged to be movable bodily about an axis 17, this angular movement being herein referred to as turning. For this pur pose a bracket 18 is secured rigidly to the guard cage 12 and is formed with a depending tubular stem 19 which is pivotally mounted in a tubular barrel 20 by means of two

ball races

21 and 22. The tubular barrel 20 forms part of a control unit which is indicated generally at 23 and includes a rearwardly-directed lug 24 which is attached to the stand 10 by means of a horizontal bolt 25, the arrangement being such that the control unit 23 can be swung upwards or downwards through a limited angle and clamped in any desired position within this range. By this means the cage 11, together with the turning axis 17, can be tilted to suit the desired working conditions.

For bringing about the mrning motion the electric motor 13 is provided with a downwardly-directed shaft 26 which is geared to the motor spindle 14 by worm gearing 27 and is therefore adapted to rotate continuously at a slow speed for the Whole time that the fan rotor 15 is running. At its lower end the shaft 26 is provided with a crank disc 28 carrying a crank-pin 29, and this is coupled by a connecting rod 30 to an anchor pin 31 fitted upon the marginal part of a circular anchorage member 32. The anchorage member 32 is arranged to be rotatable relative to a spigot 33 formed upon the bottom of the driving motor 13, a ball bearing 34 being interposed in order to reduce friction. It will be apparent that when the anchorage member 32 is held stationary (by means to be hereinafter described) the anchor pin 31 is fixed in space and therefore the rotating crank pin 29 and connecting rod 30 have the action of oscillating the head 11 about the axis 17, as is well known in connection with electric table fans; on the other hand, when the anchorage member 32 is free to rotate, the motion of the crank pin 29 merely causes said anchorage member 32 to oscillate idly, the head 11 remaining stationary. For the purpose of controlling the anchorage member 32 it is provided with a diametral bridge 35 which is connected by a shaft 36 to a braking member 37 disposed at the bottom of the control unit 23, said braking member 37 being in the form of a circular disc fast upon a spindle 38 which is freely rotatable in the tube 19 and forms the lower part of the shaft 36. The spindle 33 is held against downward movement by a collar 39 which bears against a boss 40 formed upon the bracket 18.

The upper surface of the braking member 37 is formed with an arcuate series of spaced recesses 41, these being shown more clearly in Figure 2, and they are adapted to be engaged by a ball 42 which fits snugly but slidably within a bore 43 formed in the wall of the tubular barrel 20, said ball being adapted to cooperate with the recesses 41 so as to form a non-positive locating means for the braking member 37. The ball 42 is arranged to be pressed resiliently downwards by a stiff coiled compression spring 44 disposed within the bore 43, the upper end of said spring being engaged by a ball 45 adapted to be acted upon by the extremity 46 of a control arm 47, this having a fulcrum at 48 and being rigid with a control lever 49 projecting upwards from the control unit 23. The control arm 47 is formed with two holes 50, either one of which is adapted to be engaged by a resilient ball catch 51 adapted to hold said arm 47 in its raised or its lowered position. In Figure 1 the arm 47 is shown in its raised position in which it allows the coiled compression spring 44 to assume its natural length so that it exerts very little or no force upon the ball 42; on the other hand when the arm 47 is in its lowered position its extremity 46 presses down the spring 44 through the medium of the ball 45, thereby causing the ball 42 to engage one or other of the recesses 41 with suflicient firmness to hold the anchorage member 32 sufficiently strongly to bring about a reliable turning of the head 11 under the force provided by the motor shaft 26 and crank pin 29.

It will thus be seen that the anchorage member 32 can be held by lowering the control arm 47, thereby bringing about an oscillatory turning of the head 11; on the other hand, by raising the control arm 47, the braking member 37 and the anchorage member 32 are freed so that the head 11 can remain stationary. The coiled compression spring 44, the ball 42 and the recesses 41 together form non-positive locating means for the braking member 37 and these parts are so designed that the normal gripping action will be ample for holding the anchorage member 32 stationary during normal operation of the fan, but if the turning movement of the head 11 should become impeded by an obstacle, then the braking member 37 can turn relative to the ball 42, thus preventing the fan being overturned or doing any damage.

When the control arm 47 is raised it has the effect of non-positively locking the head 11 and for this purpose the bore 43 is continued upwardly as indicated at 43a and contains a ball 55 adapted to engage a recess 56 formed in a locking disc 57, this conveniently being integral with the inner race of the ball bearing 21, and therefore being fast in relation to the bracket 18 and the head 11. The ball 55 is adapted to be pressed upwardly by a coiled compression spring 58 disposed within the bore 430, the lower end of said spring being engaged by a ball 59 pressing against the extremity 46 of the con trol arm 47. Again the spring 58 is so designed that when the control arm 47 is in its lowered position, said spring 58 can rest freely within the bore 43a, leaving the ball 55 substantially out of engagement with the locking disc 57, but when the control arm 47 is raised, the spring 58 is compressed, causing the ball to be pressed into the recess 56 with sufficient firmness to locate the head 11. Whenever desired however the head 11 can be turned manually, thereby forcing the ball 55 downwards against the force of the spring 58. The locking disc 57 can conveniently be provided with a series of recesses 56 adapted to provide a selection of locked positions for the head 11.

In the example shown in Figure 3 the head 11 comprises mainly the electric motor 13 and bladed fan rotor 15, these parts being mounted upon the top of a pedestal which forms the base 10. The turning movement of the head 11 in this case takes the form of a continuous rotation about the vertical axis 66 of the base 10, and this motion is brought about by connecting the slow vertical shaft 26 of the motor 13 with the anchorage member 32 by means of a driving gear wheel 67 on the shaft 26 meshing with an idler gear wheel 68, which latter in turn meshes with teeth 69 formed around the periphery of the anchorage member 32. Thus when the anchorage member 32 is held stationary the

gearing

67, 68 causes the head 11 to turn continuously, but when the anchorage member 32 is free, it turns idly under the driving influence of the gear wheel 67 and the head 11 remains stationary. For enabling this result to be achieved the motor 13 is mounted in the following manner.

A pair of lugs, one of which is seen at 70, is formed upon the lower part of the motor 13, and these are respectively attached by clamping bolts to a pair of upwardly-directed lugs, one of which is shown at 71, the corresponding bolt being indicated at 72. The two lugs 71 are mounted rotatably upon the top of the pedestal 65 and for this purpose they are formed integrally upon a circular plate 73 having a depending tube 19 which is mounted pivotally in a tubular barrel 20 by means of

ball bearings

21 and 22, these parts being similar to those in Figure l. The locking member 57 is again in the form of a disc which is fast upon the tube 19 and is formed with one or more recesses 56 adapted to be engaged by a ball 55 under the influence of a coiled compression spring 58 to form non-positive holding means for the locking member 57 when the control arm 47 is in its raised position. The control unit 23 in Figure 3 also includes a circular braking member 37 formed with recesses, one of which is seen at 41, for engagement by a ball 42, again so as to secure a non-positive holding action under the compressive force of a coiled spring 44. The braking member 37 is disposed at the lower end of a rod 38 which extends rotatably through the tube 19 and has a collar 39 attached to its upper end so as to hold the braking member 37 against downward movement. A flexible shaft 36a adapted to transmit torsion extends between the upper end of the rod 38 and the bridge portion 35 of the anchorage member 32, so that when the braking member 37 is held against turning, the anchorage member 32 is similarly held. Nevertheless the flexible nature of the shaft 36a enables the motor 13 to be tilted relative to the horizontal by suitable adjustment of the

lugs

70, 71, the adjustment being locked by tightening the bolt 72. When the motor is inclined in this way it still turns about the vertical axis 66, the shaft 36a bending in order to follow the orbital movements of the spigot 33.

The control arm 47 is extended outwards, as indicated at 49a so as to form an operating lever which can be moved manually if desired. For relatively inaccessible positions however the control arm 47 is formed with a pair of

holes

76 and 77 disposed at opposite sides of the fulcrum 48 and adapted to receive depending

cords

78 and 79 or like control members; thus to move the control arm 47 downwards the cord 78 is pulled and to move it upwards the cord 79 is pulled.

In order that electric current may be fed to the electric motor 13 while it is turning, a slip ring device 80 is incorporated in the control unit 23. The tubular barrel 20 is fitted at its upper part with a casing 81 carrying a pair of electrically-insulated

brushes

82 and 83 which engage a pair of

insulated slip rings

84 and 85, respectively, mounted upon an insulating sleeve 86 upon the tube 19. A flexible electric conductor 87 leads the supply to the

brushes

82 and 83, while a conductor 88 leads from the slip rings 84 and 85, and passing through the plate 73, feeds current into the electric motor 13.

If desired of course the construction shown in Figure 3 can be used in connection with a fan, the head of which has an oscillatory turning movement, a connecting rod and crank-pin mechanism (similar to that in Figure 1) being substituted for the

gearing

67, 68 and 69.

The arrangement shown in Figure 4 is a modified construction which performs the same general function as that in Figure 3. The control unit 23 is mounted at the top of a pedestal 65 forming the base and it incorporates a tubular barrel 20 carrying the

ball bearings

21 and 22, by which the tubular spindle 19 is mounted. The locking member is again in the form of a disc shown at 57a, but in this instance it is disposed at the lower end of the tubular barrel 20. Moreover it has notches such as that indicated at 56a, formed in its periphery for engagement by a ball 55a to form the non-positive holding means. A collar 92 fitted to the lower end of the tube 19 forms the inner race of a ball bearing 93 upon which the braking member 37a, is fitted, said braking member in this instance being of annular shape. It also has one or more notches 41a formed in its circumference for engagement by a corresponding ball 42a to serve as nonpositive holding means. A disc 94 secured to the braking member 37a serves as the attachment for a flexible shaft 36b which extends up the bore of the tube 19 and is attached to the bridge member 35 of the anchorage member 32.

A rotatable casing 95 is fixed to the tubular shaft 19 and carries the lug 71 by which the electric motor 13 is mounted, said motor having depending lugs 70 as in the preceding example. In this case however a pair of conducting brushes 82a and 83a are adapted to cooperate with a pair of slip rings 84a and 85a, the brushes being mounted upon the rotatable housing 95 while the slip rings are on the stationary tubular barrel 20. The current supply is fed into the control unit by a conductor 87:: leading to the two slip rings 84a and 85a; these rings transfer current to the brushes 82a and 830, which feed it to the motor by way of a plug socket 96.

For the purpose of controlling the turning movements of the electric motor 13 a control lever 49a extends radially from the lower end part of a cam member 97 which is substantially cylindrical in shape with a head 98 at its upper end. It fits rotatably within a bore 100 formed in a boss 101 on the side of the control unit 23 and it has at displaced points in its periphery a pair of segmental recesses 102 and 103 which register (for difierent positions of the control lever 49a) with bores 104 and 105, respectively, containing the balls 55a and 42a. In the position of the control lever 49a shown in Figure 4 (corresponding to the turning position of the fan) the recess 103 is out of engagement with the ball 45a so that the latter rests against a circumferential portion of the member 97. The coiled compression spring 44 is therefore compressed and its forces the ball 41 hard against the circumference of the braking member 37a, thereby locking the latter non-positively when said ball 42a engages one of the notches or recesses 41a. This of course prevents rotation of the braking member 37a and therefore holds the anchorage member 32 stationary by means of the flexible shaft 36b. On the other hand the recess 102 is in a position to receive the ball 59a which has the action of relieving substantially the whole of the stress in the compression spring 58; therefore the ball 55a is substantially free and exerts no restraint upon the lockin g member 57a. By turning the control lever 49a through a suitable angle the conditions are reversed, the recess 103 being brought into engagement with the ball 45a to free the braking member 37a, while the ball 59a is pushed into the bore 104 to stress the compression spring 58 and thereby hold the locking member 57a.

The construction shown in Figure 5 is particularly suitable for table fans and enables a compact and simple design of oscillating fan to be obtained. The base 10 embodies the control unit which is again indicated at 23 and carries a control lever 49 movable angularly about a fulcrum 48 to raise and lower a control arm 47. The control unit 23 is of substantially the same form as that in Figure l and includes a tubular barrel 20 having a passage 43, 43a containing the two locking

balls

55 and 42 with their corresponding springs 58 and 44 actuated by the arm 47 through

balls

59 and 45 to hold non-positively either the locking member 57 or the brake member, the other of said members being freed. In this case the

ball bearings

21a and 22a in the barrel 20 form the mounting for a shaft 36c which is in the form of a rigid tube having the brake member 37 fast upon its lower end, while its upper end carries the anchorage member 32 in the form of a disc; thus when the brake member is held by the ball 42, the anchorage member is prevented from rotation. The shaft 360 is utilised as a convenient pivotalmounting for the head, which latter includes a downward tubular stem having a flange at its lower end to receive the locking member 57, the latter being journalled upon the shaft 36c by a ball bearing 112; the upper end of the stern 110 is firmly attached to the bottom of the electric motor 13 and contains a ball bearing 113 also mounted upon the shaft 36c. The motor 13 (with the usual fan rotor-not shown) is free to turn upon the shaft 36c when the ball 55 is released, the oscillatory motion being imparted to it by the crank disc 28, crank pin 29 and connecting rod 30, which latter is pivoted to an eccentrically-placed stud 31 on the anchorage member 32, this of course being held stationary by the holding action of the ball 42 on the brake member 37 when the control arm 47 is in its lowered position. To render the head 11 stationary the control arm is raised, thereby freeing the brake member 37 and causing the ball 55 to hold the locking member 57.

Figure 6 shows another simple construction of mounting which is suitable for use where the turning control is disposed closely adjacent the anchorage member. The head 11 comprises an electric motor body 13 having secured rigidly to its underneath, a vertical shaft 115 extending through the tubular barrel 20, within which it is pivotally mounted by ball bearings. Firmly secured to the bottom of the shaft 115 is the locking member 57 having the recesses 56 which are engaged by the spring-pressed ball 55 as in the preceding examples. The anchorage member 32 is mounted upon the shaft 115 by a ball bearing 34 and in this instance it also forms the brake member 37 for it is formed on its underneath surface with one or more recesses 41 for engagement by the spring-pressed ball 42. In the example shown a connecting rod 30 and crankpin 29 are indicated, to produce an oscillatory turning movement, but of course gearing or other mechanism could equally well be used to couple the spindle 26 to the

anchorage member

32, 37 to produce any other required form of turning motion.

It will be understood that the details described above are given by way of example only, and that various other changes may be made. Although the invention is concerned primarily with the control of the turning movement of the head by manual operation of a control member disposed on the stationary base, it will be appreciated that other means such as a mechanical linkage or even an electromagnetic system may be used for actuating the control member on the base where remote control is required, for the invention still has the advantage that mechanical or electrical connections need not be taken to the head which turns.

What I claim is:

1. An electric fan comprising a base, a head which includes an electric motor and a fan rotor, and which is mounted to turn relative to the base, turning mechanism driven by the motor and including an anchorage member, a releasable brake device arranged to hold said anchorage member stationary to render the turning mechanism operative to turn the head, and a control member which is disposed upon the base and controls the brake device, which brake device comprises a plunger member on the base, a brake rotor movable with the anchorage member and having a recess engageable with the plunger member, and a spring operatively interposed between the control member and the plunger member, so that said spring, when stressed by the control member, presses the plunger member into operative engagement with said recess and at the same time enables the engagement of the plunger member and brake rotor to give way if the head in turning encounters an obstruction.

2. An electric fan comprising a base, a head which ineludes an electric motor and a fan rotor, and which is mounted to turn relative to the base, turning mechanism driven by the motor and including an anchorage member, a ball bearing connecting the anchorage member with the head so as to allow free relative rotation therebetween, a releasable brake device arranged to hold said anchorage member stationary to render the turning mechanism operative to turn the head, and a control member which is disposed upon the base and controls the brake device, which brake device comprises a plunger member on the base, a brake rotor movable with the anchorage member and having a recess engageable with the plunger member, and a spring operatively interposed between the control member and the plunger member, so that said spring, when stressed by the control member, presses the plunger member into operative engagement with said recess and at the same time enables the engagement of the plunger member and brake rotor to give way if the head in turning encounters an obstruction.

3. An electric fan comprising a base, a head which in cludes an electric motor and a fan rotor, and which is mounted to turn relative to the base, turning mechanism driven by the motor and including an anchorage member, a releasable brake device arranged to hold said anchorage member stationary to render the turning mechanism operative to turn the head, a locking member which is rotatable as one with the head, a locking plunger member engageable with a recess formed in the locking member, and a control member which is disposed upon the base and controls both the brake device and the locking plunger member, which brake device comprises a plunger member on the base, a brake rotor movable with the anchorage member and having a recess engageable with the plunger member, and a spring operatively interposed bctween the control member and the plunger memher, so that said spring, when stressed by the control member, presses the plunger member into operative engagement with said recess and at the same time enables the engagement of the plunger member and brake rotor to give way if the head in turning encounters an obstruction.

4. An electric fan according to claim 3, in which a spring is opcratively interposed between the locking lunger and the control member, which spring enables the engagement of the locking plunger member and the locking member to give way if turning force is applied to the head to change its angular position while the locking plunger member is engaged.

5. An electric fan comprising a base, a head which includes an electric motor and fan rotor and which is mounted to turn relative to said base, turning mechanism driven by said motor so as to be operative between the head and the base, the turning mechanism including an anchorage member, a brake device adapted to hold the anchorage member against turning relative to the base, a control member which is disposed upon the base and is adapted to bring the brake device into and out of action to control the turning of the head, the brake device comprising a brake rotor movable as one with the anchorage member and having a recess in its surface, a brake plunger disposed within a passage in the base, into which passage the control member extends, and a compression spring interposed between the control member and the brake plunger so that the control member acts through said compression spring to press the brake plunger into engagement with the recess in the brake rotor to locate the brake rotor non-positively against turning.

6. An electric fan according to claim 5, including a locking rotor rotatable as one with the head, a locking plunger disposed within that end of the passage opposite to the brake plunger and aranged to engage a recess in the locking rotor, and a compression spring interposed between the control member and the locking plunger whereby force is applied by the control member through the compression spring to the locking plunger to lock the head non-positively against rotation.

7. An electric fan comprising a base, a head which includes an electric motor and a fan rotor and which is mounted with freedom to turn relative to said base, turning mechanism including an anchorage member which is disposed on the head and is rotatable relative to said head but needs to be held stationary to make the turning mechanism effective, a brake device on the base, a flexible shaft resistant to torsion connecting the anchorage member to the brake device, thereby enabling the head to be tilted relative to the axis of turning, and a control member which is disposed upon the base and is adapted to bring the brake device into and out of action to control the turning of the head.

8. An electric fan comprising a base, a head which includes an electric motor and fan rotor and which is mounted with freedom to turn relative to said base, turning mechanism driven by said motor so as to be operative between the head and the base, and including an anchorage member which needs to be held stationary to bring the turning mechanism into action, a control unit which is mounted on the base, a rigid shaft which is carried by the control unit and upon which the head is pivotally mounted so as to enable said head to execute the turning motion, said anchorage member being fixed to said rigid shaft, which control unit comprises a brake device engageable with the rigid shaft to hold the anchorage member against turning, a locking device operable to hold the head against turning, and a movable control member arranged in one position to bring the brake device into operation and in another position to bring the locking device into operation.

References Cited in the file of this patent UNITED STATES PATENTS 1,252,595 McEwen Jan. 8, 1918 1,597,752 Aalborg Aug. 31, 1926 1,775,081 Aron Sept. 9, 1930 1,958,182 Cote May 8, 1934 1,991,080 Buttner Feb. 12, 1935