US3116679A

US3116679A - Ventilating fans

Info

Publication number: US3116679A
Application number: US158307A
Authority: US
Inventors: Solem Thorolf
Original assignee: Individual
Current assignee: Individual
Priority date: 1961-12-11
Filing date: 1961-12-11
Publication date: 1964-01-07
Anticipated expiration: 1981-01-07

Description

Jan. 7, 1964 T. SOLEM VENTILATING FANS Filed Dec. 11, 1961 .Iilll'r f /v VEN ToK United States Patent 3,116,679 VENTHJATING FANS Thorolf Solem, Stangebrua, Hamm, Norway Filed Dec. 11, 1961, Ser- No. 158,307 3 Claims. (Cl. 98-416) The present invention relates to improvements in ventilating fans.

An object of the invention is to provide a ventilating fan having a compact construction, which does not restrict the free air passage, and with details which can be simply and cheaply fabricated retaining the necessary strength and durability.

According to the present invention there is provided a ventilation fan comprising an open-ended housing, a motor mounted therein for driving the blades of the fan, a cover mounted on one end of the housing for movement in a predetermined direction between a first position in which the cover leaves the housing end open, and a second closing position, spring means urging the cover into the second position against said end, first cam means mounted on the motor for rotation about an axis parallel to the direction of cover movement, and second cam means secured to the cover and cooperating with said first cam means. Respective cam faces of the first and second cam means which are obliquely inclined relative to the axis are in conforming engagement with each other under the urging of the spring means. The faces extends in respective circular arcs about the axis, whereby the cover is moved from the second to the first position when the first cam means rotate about the axis.

For a better understanding of the present invention, and to show how the same may be carried into effect, reference 'will now be made, by way of example, to the accompanying drawing, in which:

FIGURE 1 is a vertical section through the axis of a ventilating fan, and

FIGURE 2 is a section along the line II-II in FIG- URE 1.

An open-ended housing 1 is inserted into a ventilation channel in a Wall and has at one end a peripheral flange 2 which abuts the Wall and is secured thereto. Radial arms 3 secure a motor 4, which drives fan blades 5, centrally within the housing 1. Between the motor 4 and a cover 6, which shields the inlet opening of the housing 1, a rotatable sleeve 7 is positioned co-axial with the motor. The sleeve 7 has a circular rib 7 which rotatably engages in a corresponding groove formed in the adjacent end part 4' of the motor housing. Radial arms 8 fix an outer ring 9 to the sleeve 7, the ring 9 being housed in an annular groove it} in the flange 2.

A pair of guiding rods 11, parallel to the axis of the motor 4, are supported by, and axially displaceable through bores in, the arms 3. One end of each rod 11 projects from the housing 1 to support the cover 6 while the other end of each rod 11 extends in the other direction beyond the arms 3. On these other ends are mounted helical springs 12 which act through pins passed through the rods 11 to urge the rods 11 into the housing 1.

A number of cam pieces 13 are secured to the inner surface of the sleeve 7 and are evenly distributed around said inner surface. Each cam piece 13 has a cam surface 13' which co-operates with a cam surface 14' of corresponding cam pieces 14 which project from the inside of the cover 6. The cam pieces 14 are arranged so that they can penetrate the sleeve 7 with the cam profiles 14' engaging the cam profiles 13.

The sleeve 7 is rotated by means of a line 15 the ends of which are secured to the ring 9. The pitch of the cam surfaces 13', 14 is so chosen that by rotating the sleeve approximately a quarter of a revolution the cover Patented Jan. 7, 1954- 6 is moved from a fully opened position to a closed position where the cover 6 is pressed against the flange 2 by the springs 12. During this movement the rods 11 pass freely between two adjacent arms 8.

A clockwise rotation of the sleeve 7, and thus the cam surfaces 13, from the position shown in FIGURE 2, allows the cam pieces 14 to penetrate the sleeve 7 under the action of the springs 12. The rotation can be continued until the cover 6 bears against the flange 2.

By rotating the sleeve 7 in the opposite direction the cam surfaces 13 acting on the cam surfaces 14 force the guiding rods 11 against the action of the springs 12 and thereby move the cover 6 outwardly until the cover reaches the fully opened position.

The current to the motor 4 is controlled by a tumbler switch 16 the tumbling arm 17 of which projects between two radial arms 8. These two arms 3 co-operate with the arm 17 to switch the current on and off in the fully open and closed position respectively of the cover 6.

The springs 12 exert axial forces on the guiding rods 11 which act through the cover 6, cam pieces .13, 14 and sleeve 7, and hold the rib '7' engaged in the circular groove in the end part 4'.

In the embodiment shown and described, the cams 'formoving the cover 6 do not project outside a prolongation of the circumference of the motor and consequently the free air passage is not restricted.

What I claim is:

1. A ventilating fan comprising in combination, a housing having two open ends, a fan driving motor in said housing, a housing cover, means for fixedly mounting said motor in said housing and for mounting the cover on the housing for movement of the cover toward and away from one of said open ends of the housing, said mounting means including a plurality of arm members extending between said housing and said motor in respective angularly spaced radial directions, a plurality of guiding rods, means for slidably mounting said guiding rods on respective ones of said arm members for movement toward and away from said one of said open ends, said housing cover being fastened to said guiding rods, spring means including a plurality of coil springs mounted on said guiding rods and connected to said housing and to said cover for urging the cover toward said one of said open ends of the housing, a first cam member and a second cam member, means rotatably securing said first cam member to said motor for rotation about an axis of said housing passing through said open ends, means fixedly securing said second cam member to said cover, said first and second cam members each having a plurality of cam faces obliquely inclined relative to said axis and extending in respective circular arcs about said axis, the cam faces of each cam member conformingly engaging the cam faces of the other cam member, and means for rotating said first cam member.

2. The device as defined in claim 1 wherein said last mentioned means include a sleeve member fixedly fastened to said first cam member, and means for rotating said sleeve member about said axis.

3. The device as defined in claim 1 together with switch means responsive to rotation of said first cam member for controlling said motor.

References Cited in the file of this patent UNITED STATES PATENTS 1,890,758 Townsend Dec. 13, 1932 FOREIGN PATENTS 84,361 Norway Aug. 7, 1954 108,911 Sweden Nov. 2, 1943 152,665 Sweden Dec. 13, 1955