An automatic temperature responsive ventilator including a housing having side walls defining an air passageway and an openwork grid across the passageway. At least one shutter is mounted within the housing, with one end of one shutter element being associated with a bimetallic spring that is received within an opening in one housing side wall. A cap is received over the spring from the outside to hold the spring in place and protect the spring from the elements and from damage during installation. An outer end of the spring is held by a slot in the side wall and an inner end of the spring is secured to a rod that is attached to the shutter. Variations in ambient temperature cause the shutter element to open and close automatically.

BACKGROUND OF THE INVENTION 
The present invention relates to a ventilator structure of the type that is 
normally disposed in the foundation of a dwelling or other type building 
structure. Ventilators are normally spaced around the periphery of a 
building, dwelling structure, or the like so as to permit proper 
ventilation beneath the floor level. Such ventilators are normally 
provided with one or more louvers that are moveable between a closed 
position that generally cuts off air flow through the ventilator, 
desirable during the colder months, and an open position that permits good 
air flow from the outside underneath the structure, normally during the 
warmer months. 
Generally speaking, such vents have included two types, namely manual vents 
where one or more shutters is received in an air passageway with manual 
means to open and close same; and automatic vents where one or more 
shutters is received in a passageway and connected by some means to a 
thermally responsive spring, such as a bimetallic spring whereby the 
shutters automatically open and close, depending upon the ambient 
temperature. The present invention is of the latter type and constitutes 
an improvement over those known to exist. Particularly, the vent of the 
present invention is economical to manufacture, easy to install, utilizes 
a thermally responsive coil spring that, though exposed to ambient 
temperature for reaction thereto, is protected from the elements and 
possible damage due to mounting, and is directly connected to the shutter 
mechanism via a mounting means for same. 
SUMMARY OF THE INVENTION 
It is an object of the present invention to provide an improved, automatic 
ventilator assembly suitable for mounting in the foundation of a dwelling 
structure or the like so as to control the ingress of air beneath the 
floor level of same. 
Another object of the present invention is to provide an improved automatic 
ventilator structure that utilizes a bimetallic spring for automatic 
opening and closing of shutter elements in the vent structure. 
Yet another object of the present invention is to provide an improved 
ventilator assembly where the housing for same is molded of a synthetic, 
polymeric material and is unitary in structure and wherein a bimetallic 
spring operable to automatically open and close shutter elements of said 
ventilator is received within one of the side walls of the housing so as 
to be exposed to ambient temperature while being protected from the 
elements. 
Still further, another object of the present invention is to provide an 
improved automatic ventilator assembly that may be conveniently installed 
in existing openings in foundation walls without the need for mortar. 
Generally speaking, the present invention relates to an automatic 
ventilator structure comprising a housing, said housing having peripheral 
side walls defining an air passageway therethrough; at least one shutter 
element received in said air passageway and mounted to said housing for 
rotary movement between a closed position where the passageway is 
generally closed and an open position where the passageway is generally 
open to the passage of ventilating air therethrough; 
temperature-responsive spring means received in one of said side walls of 
said housing and secured against rotation therein; and rod means connected 
directly between said spring means and said shutter element whereby 
temperature variation effects on said such spring means cause said shutter 
element to move toward an open or closed position. 
More specifically, the automatic ventilator of the present invention 
preferably includes a molded plastic housing that is unitary in structure 
insofar as side walls, protruding connector elements, and grid structure 
are concerned. Behind the grid structure and within the side walls are 
mounted a plurality of shutter elements that are interconnected for 
simultaneous movement. The side walls define an air passageway 
therebetween through which ventilating air may pass or be excluded, 
depending upon the attitude of the shutter elements. One of the side walls 
further defines an opening, generally circular in nature, with a 
peripherally protruding slot in which a coil bimetallic or thermally 
responsive spring is received with an outer end of the spring being 
received in the slot to secure against rotation of the spring in general 
upon experiencing temperature variations. An opposite end of the spring is 
received in a slotted rod, an opposite end of which is secured to one of 
the shutter elements whereby temperature variations significant to produce 
an expansion or contraction effect on the coil spring cause the rod to 
rotate in the appropriate direction and to drive the shutter toward an 
open or closed position. 
The bimetallic spring is received within the side wall opening and 
preferably has a retainer-protector cap secured thereover. An outer end of 
the cap is received in an appropriate recess surrounding the opening 
whereby a continuous outer surface of the side wall exists when the cap is 
in place. Depending from the outer surface of the cap are a plurality of 
prongs having shoulder elements at an opposite free end thereof. Certain 
of the shoulder elements are presented outwardly to engage an inner 
surface of the side wall while certain of the shoulder elements are 
presented inwardly to engage a portion of the spring. The spring is thus 
secured in place within the side wall. 
Protruding connector elements from the housing are provided to optionally 
receive a collar which may be secured thereto. The collar generally 
includes side walls defining an opening therewithin that corresponds in 
general to the size of the passageway of the vent housing and further has 
an outwardly extending peripheral flange around the side walls. A vent 
with a collar attached may be suitably employed in an opening, a 
foundation, or the like, with the protruding peripheral flange of the 
collar contacting an outer surface of the structure wall and covering any 
space between the vent housing and the wall per se.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Referring to the figures, preferred embodiments of the present invention 
will now be described in detail. FIG. 1, for example, illustrates a 
ventilator according to teachings of the present invention in a preferred 
environment for use of same, that is a foundation wall W of a dwelling 
structure or the like where the ventilator provides means for ingress of 
ventilating air beneath the floor with the capability of controlling the 
amount of air depending upon ambient temperature. The vent generally 
indicated as 10 is thus shown mounted in the wall W. Under normal 
construction of the wall W from brick as shown, a rectangular shaped 
opening would be provided in the wall wherein the ventilator may be 
received and appropriately secured. 
As to the particular details of the preferred ventilator construction, a 
housing generally indicated as 20 is provided, being represented by an 
openwork grid structure 21 which is preferably of unitary construction 
with side walls 22, 23, 24 and 25. Side walls 22, 23, 24 and 25 define an 
air passageway in which a plurality of shutter elements 31a, 31b, and 31c 
are received and mounted to side walls 23 and 25 by mounting elements 32 
for limited rotary movement thereat between an opened and closed position, 
with the exception of one end of one of the shutter elements. As shown in 
FIG. 2, shutter element 31a has a special mounting at one end which will 
be described hereinafter. Housing 20 further has a plurality of 
protuberances 26 secured thereto having openings 27 therethrough. A collar 
generally indicated as 13 may also be provided which is made up of a 
plurality of side walls 14 having peripheral flanges 15 secured thereto 
and extending outwardly therefrom. Collar 13 is thus received adjacent 
protuberances 26 and has openings 16 in certain of the side walls thereof 
that correspond to the openings 27 in protuberances 26 of housing 20. In 
this fashion, collar 13 may be totally secured to protuberances 26 or 
certain of the matching openings may receive a securement pin 17 while 
certain receive an elongated element 18 that not only secures the collar 
to the housing, but extends into the side of wall W so as to secure the 
ventilator in place (See FIG. 1). In this fashion, utilizing collar 13 a 
ventilator 10 according to the present invention may be installed without 
the need for mortar, and moreover will fit various size openings in a 
foundation wall, where the difference between the size of the opening and 
the ventilator housing will be covered by the peripheral flange 15 of 
collar 13. 
Housing 20 may further be provided with a screen 30 that is located behind 
grid 21 and secured in place. Screen 30 precludes the passage of insects 
through the air passageway of the ventilator structure. Referring 
particularly to FIGS. 2 through 6, one of the side walls, 23 as 
illustrated, further defines a generally cylindrical opening 28 having a 
peripheral slot 29 extending outwardly therefrom and being generally 
surrounded by a contersunk recess 28'. A thermally responsive coil spring 
40 is receivable in opening 28 with an outer end of same extending into 
slot 29 to secure spring 40 against rotation. Only a portion of spring 40 
is illustrated in phantom in FIG. 3 for the sake of clarity. An inner end 
of spring 40 is secured to a mounting rod 34 for shutter element 31a. Rod 
34 is secured at one end 34' to shutter element 31a and has a slotted 
opposite end 35 in which the inner end of spring 40 is received and held 
by lip 35'. End 34' of rod 34 is preferably non-circular in shape, and 
most preferably is rectangular. A like shaped hole in shutter element 31a 
receives end 34' whereby relative rotation between the two is precluded. 
Rod 34 further has a collar element 36 intermediate its length to properly 
position same with respect to spring 40 and the interior of housing side 
wall 23. Spring 40 is thus received within side wall 23 of housing 20 and 
is held thereby by a cap 45 that is securably received in opening 28. Cap 
45 has an interior shoulder 46 with a plurality of prongs 47 and 49 around 
same, located in a generally circular pattern. Prongs 47 and 49 have 
shoulder sections 48 and 50 respectively at outer free ends of same. 
Shoulder sections 48 and 50 extend in opposite directions whereby shoulder 
sections 48 may reside against the interior surface 23' of side wall 23 
while shoulder sections 50 engage the side of coil spring 40. Cap shoulder 
46 resides in countersink 28' of opening 28 while shoulders 48 and 50, as 
mentioned above, extend inwardly and reside against the inner surface 23' 
of side wall 23 or coil spring 40 respectively so as to maintain coil 40 
in place and protect same against the elements or damage during 
installation. Since cap 45 resides in countersink 28', a continuous smooth 
outer surface is provided along side wall 23. 
Shutter elements 31a, 31b and 31c are preferably interconnected by an 
elongated strip 33 that extends therebetween within housing 20 and is 
secured to each shutter by studs 33' for pivotal movement. In this 
fashion, as spring 40 is affected by ambient temperature to contract or 
expand, drive rod 34 turns in the responsive direction and causes shutter 
element 31a to rotate towards a closed or an open position, depending upon 
the particular temperature. In like fashion, since connector strip 33 is 
secured between all of the shutter elements, all of the elements 
simultaneously move in the direction of an open or closed position. 
In a preferred situation, the housing and collar of the ventilator of the 
present invention are each of unitary construction, having been molded 
from a thermoplastic, polymeric material. 
Having described the present invention in detail, it is obvious that one 
skilled in the art will be able to make variations and modifications 
thereto without departing from the scope of the invention. Accordingly, 
the scope of the present invention should be determined only by the claims 
appended hereto.