Claims:
I claim
1. In a roof ventilating device having plural louvers on opposite sides thereof adapted to swing open in response to a differential in air pressure across the louvers, an improved means for simultaneously driving all the louvers to open position irrespective of said pressure differential response comprising: an actuating lever adjacent each louver biased into a released position in which the levers drive their respective louvers to open position, a latch member for each of said actuating levers holding it in a restrained position out of driving engagement with its respective louver, and a single elongated flexible resilient member having a closed loop configuration stretched under tension into association with each of said plurality of latch members and holding them in actuating member-restraining position, and release means for releasing the tension of said resilient member thereby simultaneously releasing all of said latch members permitting all of said louvers to be driven simultaneously to open position.
2. A roof ventilating device as claimed in claim 1 in which said release means includes a manually operable member for momentarily releasing the tension of said resilient member.
3. A roof ventilating device as claimed in claim 1 in which said release means includes a first manually operable member accessible from the exterior of said ventilating device and a second manually operable member accessible from the interior of said ventilating device, both of said manually operable members functioning when operated to release the tension of said resilient member.
4. A roof ventilating device as claimed in claim 1 in which said release means includes a fusible link exposed to the temperature of the gases passing through the roof ventilating device.
Description:
BACKGROUND OF THE INVENTION
The invention herein is concerned with power driven roof exhausters or building roof ventilators adapted to have their louvers forcibly opened by spring loaded means tripped in response to high temperature. The power exhausters or ventilators are normally of the type adapted to be mounted on top of a building roof curb which frames a vertical opening in a building roof by upstanding walls. The ventilator or power roof exhauster (if provided with a fan and motor) includes spring loaded dampers normally urged to a vertically closed position. Higher than atmospheric air pressure inside the building (as might be caused by hot air or by the action of a power driven fan) forces the dampers open against torsional springs or other type means urging the dampers closed. An example of the torsionally loaded damper is shown in copending application, Ser. No. 61,251 filed Aug. 5, 1970, and now U.S. Pat. No. 3,651,750. Attention is also invited to U.S. Pat. No. 3,396,652 wherein is shown a power roof exhauster with each damper capable of being forcibly opened by spring means whenever the heat fusible link is rupted adjacent each louver.
BRIEF SUMMARY OF THE INVENTION
It is an object of this invention to provide a power roof exhauster or heat relief vent having a release mechanism responsive to heat above a predetermined temperature for causing louvers thereof to be forced to an open position.
It is a further object of this invention to provide release mechanism capable of releasing plural mechanism adjacent respective louvers which will move the louvers to an open position.
It is a still further object of this invention to provide means for manually causing release of plural mechanism and opening of respective louvers.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be more fully understood and further objects and advantages thereof will become apparent when reference is made to the following detailed description of the preferred embodiment of the invention and the accompanying drawings in which:
FIG. 1 is a perspective view of a building roof ventilator or power exhauster mounted on a roof curb;
FIG. 2 is an elevation view of a building roof ventilator or power exhauster similar to FIG. 1;
FIG. 3 is a cross-sectional view (slightly enlarged) taken along line 3--3 of FIG. 2, and showing the fan and motor arrangement of the power roof exhauster embodiment;
FIG. 4 is a perspective view of a base frame only of a roof ventilator (or power roof exhauster) showing particularly the heat releasible mechanism for causing latch mechanism to function;
FIG. 5 is a cross-sectional view taken along line 5--5 of FIG. 4;
FIG. 5A is a cross-sectional view similar to FIG. 5, but showing the latch mechanism released and showing the louver in the process of being opened; and
FIG. 5B is a cross-sectional view similar to FIG. 5A, but showing the louver in fully opened position.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawing and, in particular, to FIGS. 1 and 2, there are shown in perspective and frontal views respectively a roof ventilator or power roof exhauster designated generally by the numeral 10. It is mounted on top of a building roof curb 12 which frames a vertical opening in the roof. Upstanding walls of the curb provide a support for receiving a base of a frame of a ventilator or power roof exhauster and define a passage for air or hot gases. Side walls of the ventilator, as shown in FIGS. 1 and 2, are provided with spring loaded louvers 14 which are normally biased to a closed vertical position. A cover 15 is provided over the frame.
FIG. 3, which is a cross-sectional view of FIG. 2, shows an axial fan 16 located in an orifice or throat 18 and driven by an electric motor 19. This arrangement defines the power roof exhauster as distinguished from a roof ventilator which does not include the motor, fan or orifice. FIG. 4 illustrates a base 13 with release mechanism associated therewith. It is to be understood that this base is capable of being, as shown in FIG. 4, for use with a ventilator; or it is capable of being used in conjunction with the fan, motor and orifice, as shown in FIG. 3, to define a power exhauster. In either embodiment the release mechanism is identical.
The outward appearances of a ventilator and a power roof exhauster are identical. In either embodiment air passes upwardly through curb 12, through the frame and to the atmosphere through the louver openings.
As previously indicated louvers 14 may be of the type disclosed in copending U.S. Pat. application, Ser. No. 61,251 filed Aug. 5, 1971. The louvers are biased to a normally closed position in respective openings of frame 15. Air inside the ventilator or power exhauster frame at a pressure slightly above atmospheric is sufficient to cause the louvers to swing open in opposition to means urging the louvers closed. Air is thereby exhausted to the atmosphere.
Mechanism is provided for forcibly opening the louvers in the event the temperature of the air rises to a predetermined level. This provides an exit for hot air or gases as would be caused, for example, by a fire. In FIG. 4, there is illustrated a plurality of actuating members 20 pivotally mounted on a bracket 22 secured to the top of base member 13. Torsion springs 24 are adapted to urge actuating members 20 to an outward position. In FIG. 4 and in the cross-sectional view of FIG. 5 the actuating members are shown in a restrained or cocked position against the bias of spring 24. They are retained in this position by means of respective latches 26 which are pivotally mounted to bracket 28 secured to the inside periphery of base portion 13. The latch includes a catch portion 30 near its upper extremity for the purpose of providing a surface for cooperating with U-bolt 32 in order to hold actuating member 20 in cocked position. See FIG. 5. The surface defining catch portion 30 is disposed at an angle sufficient to hold the horizontal portion of U-bolt 32 when the latch is retained in the position shown in FIG. 5 by restraint of cable 34. However, any relaxation of cable 34 permits U-bolt 32 to slip off the angularly disposed catch portion 30. The actuating member 20 is then free to pivot outwardly for causing louver 14 to swing open. When one latch is released, all latches become released.
A loop-like cable arrangement comprised of cables 34 with tension coil spring 40 defines an arrangement to hold all actuating members 20 cocked, or to permit them to be simultaneously released. Cables 34 are arranged into a loop which pas through eyelets 36 attached at the lower portion of latch 26. The loop is completed by a heat-fusible link 38 on one side and a tension coil spring 40 on the other. Fusible link 38 is by-passed by a cable portion 42 which is provided for the purpose of retaining the cables 34 in a loop even after rupture of link 38. The cables will hang somewhat loosely through the four eyelets 36.
Under normal operating conditions the release mechanism has a static function to retain the actuating members 20 in cocked position. The mechanism does not interfere with air passing through a ventilator or power exhauster and over the louvers to the atmosphere. The louvers swing freely in response to any inside pressure slightly above atmospheric sufficient to overcome whatever means are provided which tend to close the louvers. However, in the event of fire, the temperature in the building causes fusible-link 38 to part. This permits the loop defined by cables 34 to expand or relax so that there is less tension on latches 26. The latch will be caused to pivot. This permits the horizontal bar of U-bolt 32 to slip off catch portion 30. The tension on the loop applied by spring 40 is normally sufficient to hold latches 26 in position. However, upon parting of link 38, the loop becomes larger, and the spring tension is reduced or is relaxed altogether. Even if some spring tension remains after rupture of link 38, the sudden, even if only temporary, relaxation of pull on latches 26 permits bars 32 to slide off catches 30 with resulting release of spring loaded actuating members 20.
It will be noted in FIG. 4, that manual release means are provided for effective tripping of actuating members 20, even without parting of fusible link 38. An outside release is operatively attached to handle 43. Cable 44 passes therethrough and is anchored at one end to an eyelet 46 in base member 13. The other end of cable 44 is attached to the end of spring 40, or to cable 34 close to the end of the spring. By pulling handle 43, spring 40 is stretched to enlarge the loop of cables 34. This releases the tension applied to latches 26 by cables 34 whereby actuating members slip off catch portion 30. A pull on handle 43 followed by quick relaxation to interfere with constant tension on latch 26 is another method of obtaining release.
Another manual release, accessible from the inside of the building, is provided. A cable 48 is similarly attached to spring 40 at the end opposite to where cable 44 was attached. A manual pull on cable 48 causes it to slide through eyelet 50 and stretch spring 40 for interfering with the constant tension on latches 26 applied by cables 34.
A release mechanism has been disclosed capable of causing opening of louvers in a ventilator or power roof exhauster. The release of cocked actuating members is effected by interfering with the normal tension applied by the cable loop. This tension is changed either by the parting of a fusible link or by manual interference with a spring tension.
An installation having a power exhaust unit as disclosed in FIG. 3 is provided with a similar release arrangement for opening louvers 14.
One embodiment of the invention has been disclosed. Obvious modifications can be made thereto without departing from the spirit of the invention.