US 3415178 A
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Dec. 10, 1968 Filed May 4, 1967 9 SPEED CONTROL D. BALL ETAL 3,415,178
VENTILATING SYSTEM AND DEVICE 2 Sheets-Sheet 1 SENSOR INVENTOES 00mm ALL Foam;- Gum/[Y ATTORNEYS Dec. 10, 1968 0. BALL ETAL 3,415,178
VENTILATING SYSTEM AND DEVICE Filed May 4, 1967 2 Sheets-Sheet 2 INVENTOIZS ll5v.A- flow/440 544x.
P05527- Gum/[r ATTOENEYS United States Patent 3,415,178 VENTILATING SYSTEM AND DEVICE Donald Ball, Deerfield, and Robert Gurney, Chicago, Ill.,
assignors to ILG Industries, Inc., Chicago, III., a corporation of Delaware Filed May 4, 1967, Ser. No. 636,195 4 Claims. (Cl. 98-33) ABSTRACT OF THE DISCLOSURE A system and device for ventilating a room communicating with an air flow duct through a passageway, including a damper movable into and out of a position in which the passageway is obstructed, with means such as a motor being provided to permit selective movement of the damper to a desired position and to maintain it in such position.
The present invention relates to systems for ventilating individual rooms within a building and, more particularly, is directed to an improved ventilating device adapted to control the flow of air from a room to be ventilated into an exhaust duct.
In modern buildings, particularly apartment and ofiice buildings, it is desirable to provide for the exhaust of air from rooms such as kitchens, bathrooms, conference rooms, small offices and work rooms. In large multistoried buildings, a common approach to this problem has been to provided vertical riser ducts within the building which communicate, through passageways, with various rooms on each floor adjacent the duct. An exhaust fan is provided at the top of the riser and draws air continuously from the rooms through the duct and passageways and exhausts it to the atmosphere. With such a system, which involves a continuous flow of air from each room, a high capacity exhaust fan is needed and, in addition, the heating or air-conditioning equipment must be sized large enough to handle the load represented by this air change. Thus, such a system increases both the initial cost and the operating cost of the building.
Another approach has been to provide a fan in each room which exhausts into the riser duct. The duct in turn may be provided with a large exhaust fan which can be of a lower capacity than the exhaust fan of the duct in the system described above. A system which includes an individual fan for each room involves a significant initial expense and each fan presents the problem of noise in each room as well as a problem of maintenance.
Accordingly, the principal object of the present invention is to provide an improved system for ventilating selected rooms within a building.
Another object of the invention is to provide an improved device for controlling the flow of air from a room to be ventilated into an exhaust duct.
Other objects and advantages of the invention will become apparent with reference to the following description and the accompanying drawings.
In the drawings:
FIGURE 1 is a diagramatic fragmentary elevational view of a building ventilating system showing various of u the features of the invention;
FIGURE 2 is an enlarged perspective view of a ventilating device forming part of the ventilating system of FIGURE 1;
FIGURE 3 is an enlarged elevational view of the de vice of FIGURE 2 with a portion of the device removed for purposes of illustration:
FIGURE 4 is a sectional plan view taken along the line 44 of FIGURE 3;
3,415,178 Patented Dec. 10, 1968 FIGURE 5 is a sectional end view taken along the line 55 of FIGURE 4; and
FIGURE 6 is a wiring diagram for the electrical system of the device shown in FIGURES 2-5.
Very gene-rally, a ventilating system in accordance with the present invention is shown in the illustrated embodiment as incorporated into a building 10 provided with an air flow duct 12 which extends vertically to an opening 14 communicating with the outer atmosphere at the top of the building. A roof ventilator 16 is provided at the opening 14 and may include an exhaust fan (not shown) to effect a flow of air through the duct and outwardly of the building. In very tall buildings, however, the natural draft created by the height of the building may be suflicient to effect an adequate flow of air, in which case an exhaust fan would not be necessary.
As shown, the building 10 includes several floors or levels 18, each of which defines a portion of a room 20 located adjacent the riser duct 12 and separated therefrom by walls 21. Passageways 22 extend through the walls 21 so as to provide communication between each room 20 and the duct 12. Thus, air will be drawn from the various rooms 20 through the passageways 22 into the duct 12 from which it will be exhausted through the opening 14.
Located within each passageway 22 is an air flow control device 24 which includes a frame or housing 26 which is effective to plug the passageway 22 but which defines an opening 28 through which air may flow. A damper 30 is mounted on the frame 26 and is movable between a closed position in which it obstructs or closes the opening so as to preclude the passage of air therethrough and an open position in which air is free to flow through the opening. The damper 30' is biased to the closed or obstructing position and a motor 32 is provided to permit selective movement of the damper to a non-obstructing position when desired.
More particularly, the housing 26 of the device 24 is of a rigid sturdy construction and includes a top wall 36, a bottom wall 38, end walls and 42, and a back wall 44, all of which are preferably formed of sheet metal. The back wall 44 is positioned nearest the riser duct 12 when the device is mounted within a passageway 22. The end walls 42 include flanges 46 along their front edges, i.e., those edges furthest from the back wall 44. The flanges facilitate the securing of the device within a passageway 22 and also facilitate the attachment to the front of the housing of a grill 48 (FIG. 2) which is the only portion of the device visible to an occupant of the room 20.
The back wall 44 is formed to provide the opening 28 which is of a rectangular configuration. Those portions of the back wall located along the vertically extending side edges of the opening 28 are offset outwardly away from the interior of the housing to form flanges 50 which streamline the opening and provide a nozzle effect for the air flowing through the opening.
Mounted adjacent the rearward or outer surface of the 'back wall 44, i.e., that surface opposite the interior of the housing, is a bafile 52 defined by a plate 53 fiorined into a V-shape and mounted on the bight or mid-portion of a U-shaped rod 54 or ball so as to position it with the apex of the V nearest the back wall 44 andwith diverging halves of the plate '52 projecting away from the back wall in opposite directions. The rod 54 also positions the baffle in slightly spaced relation to the back wall and, hence, to the plane of the opening 28. That surface of the baflle located nearest the back wall and facing in a direction opposite to the flow of air through the opening 28 is covered with a layer 55 of sound deadening material such as a fiberglass or a plastic foam.
The housing 26 is of such a size as to span the passageway 22 in both height and width so as to preclude air from flowing intermediate the housing and the surfaces of the walls 21 defining the passageway. Thus, the only flow of air through the passageway is through the opening 28.
The damper 30 is mounted on the back wall 44 for pivotal movement by means of a hinge 56 supported with the hinge axis disposed vertically. The damper 30 is of sufficient size to obstruct or close the opening 28 when properly positioned relative to the opening, and a spring 58 is provided at the hinge 56 to bias the damper toward the closed position.
The hinge 56 mounts the damper 30 relative to the back wall 44 so as to provide a space between the damper and back wall when the damper is parallel to the back wall. This space is occupied by a layer of insulating material, preferably resilient, which is bonded to the rearward surface of the damper and is effective to minimize vibrations or rattling of the damper and to minimize or eliminate sounds which might tend to be created as the damper is swung into the closed position by the biasing spring 58.
Movement of the damper 30 to the open position is effected by the motor 32 housed within a motor enclosure 60 provided at one corner of the interior of the housing 26. The motor enclosure includes a top wall 62, from the underside of which the motor 32 is suspended (FIG. The motor 32 is a preferred embodiment is a selfstarting synchronous clutch motor rated at 5 watts and geared down to four revolutions per minute. The motor has a drive shaft which extends upwardly through the top wall 62 and on which is mounted a pulley 66 positioned above the top wall. The pulley includes vertically spaced flanges 68 and 70, positioned above the top wall, the uppermost of which is provided with an opening or hole 72 (FIG. 4) which receives one end of a cord 74 connected at its opposite end to that edge of the damper which is located farthest from the axis of the hinge 56. As the pulley 66 is rotated by the motor 32, the cord 74 is coiled upon the pulley core until the damper has reached the fully open position. In the illustrated embodiment, this position is defined by the engagement of the damper with a portion of the motor enclosure 60. However, an adjustable stop may also be provided, thereby permitting control of the amount of air being handled. At such point, the motor stalls so that a constant torque is applied to the pulley to maintain the damper in the open position, but no added strain is placed upon the motor. Of course, when the current supplied to the motor is interrupted, the torque will no longer be applied and the damper will be urged toward the closed position by the force of the biasing spring 58, unwinding the cord 74 from the pulley as it moves.
A representative circuit for controlling the operation of the motor 32 is illustrated in FIGURE 6. This circuit is also preferably electrically coupled to the lighting circuit of the room in which the device 24 is located so that the lights of the room are turned on, and the motor 32 is energized by the same switch 76.
More specifically, the circuit comprises the switch 76 connected in series with a resistance 80 of a thermal relay 82 (FIG. 5) and the series combination is connected to a voltage supply such as the AC electrical power supply for the room. The motor 32 is connected in series with a normally open switch 86 of the thermal relay 82 which is closed after a very short period of time by the heat generated by the passage of current through the resistance 80. The serially connected thermally operated switch 86 and the motor 32 are connected to the power supply. In a preferred embodiment, the resistance 80 and switch 86 are provided by a thermal relay tube 82 manufactured by the Amperite Corporation, and sold as 4 Part Number 115N069. Such a tube is capable of prolonging the current flow to the motor for 2 to 3 minutes. Other time delay devices could of course also be used.
In the operation of the circuit, when the switch 76 is closed to energize the lights within a room 20, current begins to flow through the resistance and, in a short period of time, creates sufficient heat to close the switch 86, thereby energizing the motor 32. When the switch 76 is opened, as when the lights in the room are turned off, the switch 86 will remain closed for a predetermined period of time, that is, until the heat created by the resistance 80 has been sufficiently dissipated. Thus, current will continue to flow through the motor 32 after the lights in the room have been turned off.
The circuit also includes a double pole safety switch 88 which, when open, disconnects both the resistance circuit and the motor circuit from the power supply and which therefore permits maintenance personnel to service the device while the room lights are on. The switch 88 is operated by a toggle 90.
The operation of the ventilating system and device can now be readily understood. When the lights are turned on in a room 20 provided with a device 24, the motor 32 is energized and rotates the pulley 66 through a clutch associated with the motor. Rotation of the pulley causes the cord 74 to become coiled around the pulley core so as to retract the cord and withdraw the damper 30 to an open position in which the damper abuts and engages the motor enclosure 60. Although the damper ceases to move, the motor continues to operate. The stalling of the clutch motor maintains a tension on the cord 74 and, thus, maintains the damper in the open position. While the damper is open, air is drawn from the room 20 into the air flow duct 12 and exhausted from the building.
When the room lights are turned olf, the current flow to the motor is not immediately interrupted and the damper is maintained in the open position for a predetermined period of time, e.g., 2 to 3 minutes. When the switch 86 eventually opens, the motor ceases to apply a torque to the pulley 66 and the pulley unwinds as a result of the biasing force of the spring 58 which urges the damper to the closed position.
It should be appreciated that not all rooms will be exhausting simultaneously during normal operating conditions. Hence, the load on the air conditioning plant and heating plant is not as great as with a continuous exhaust system, and these plants can be of lesser capacity and, thus, represent less of an initial investment and less of an operating expense. In like manner, the central exhaust fan need not have as great a capacity and will also be less costly to install and operate. Furthermore, the proposed system is more economical to operate than the individual exhaust fan system since the device 24 is less costly than a fan both in installation and operation. The individual fans also create significantly more noise than the device 24.
It is desirable to provide for a constant fiow of air through each of the devices 24 when the damper 30 is in the open position. That is, it is desirable to insure that the opening of the damper 30 in any of the rooms 20 will result in a predictable rate of flow of air from the room. It will be appreciated, however, that the rate of How of air is a function of the pressure within the riser duct 12 which is, in turn, a function of the number of dampers 30 which are open and the operating characteristics of the fan, if any, at the top of the duct. For example, the rate of flow of air past one open damper 30 will be much greater if all other dampers are closed than if all other dampers are open, all other factors remaining constant.
In order to provide for a relatively constant exhaust of air from any room, regardless of the use or non-use of any or all of the devices 24 in the remaining rooms, a control system 92 is provided (FIG. 1) and includes, in addition to the motor operated fan, a speed control 94 for the fan motor, and a pressure sensor 96 located within the riser duct 12. Preferably, the fan motor is of such a construction that its speed is dependent upon the voltage supplied to it. The speed control 94 is, in effect, a voltage regulator, the output of which is controlled by an electrical resistance (not shown). The sensor 96 converts changes in pressure to changes in the electrical resistance which controls the output of the speed control.
Thus, in the operation of the system, a change in the pressure within the riser duct 12, caused for example by the opening or closing of dampers 30 within rooms 20, acts through the sensor 96 to cause a change in the electrical resistance which controls the output of the speed control 94, thereby varying the speed of the fan and compensating for the change in pressure. A fairly constant pressure within the riser duct, and a fairly constant flow of air from the rooms 20 when the duct 30 is open, is thus assured.
A ventilating system and device for use therein have thus been shown and described with respect to a particular structural embodiment. It should be apparent, however, that various modifications may be made in the system and device shown and described without departing from the scope of the invention.
For example, the system as shown is adapted to exhaust air from rooms in a building. However, if a static pressure is maintained in the air flow duct, the system might also be used to provide a flow of air into the rooms. In such case, it may be desirable to mount the damper 30 on the duct side of the opening 28. Also, it should be apparent that the damper can be used to control the passage of light into a room, and to serve as a firedamper under certain circumstances.
Finally, various systems such as the system 92 could be devised for insuring a constant pressure in the duct 12, including a control vent in the ventilator 16 to vary the size of the opening at the upper end of the duct and, thus, vary the flow of air from the duct.
Various features of the invention are set forth in the following claims.
What is claimed is:
1. A system for providing ventilation for a plurality of separate rooms defined by walls of a building, each of said rooms to be ventilated being provided with an electrically energized light source and an electrical light ing circuit for supplying energy to said light source, said lighting circuit including a switch for controlling the passage of current through said lighting circuit, said system comprising an air flow duct extending in proximity to each of the rooms to be ventilated and communicating with the atmosphere outside the building to eflect a flow of air through said duct, means defining a passageway in a Wall of each room providing communication between the room and said duct, a damper adjacent said passageway movable between a closed position to obstruct the flow of air through said passageway and an open position to permit the flow of air through said passageway, and selectively operable means for effecting movement of said damper between said closed and said open positions, said selectively operable means including an electrically operable motor, and an electrical circuit for supplying current to said motor, said motor circuit being electrically connected to said light switch so as to enable said light switch to control the flow of current through said motor circuit as well as through said lighting circuit so that energization or de-energization of the light of the room also initiates or ceases the operation of said motor.
2. In a building which includes a ventilation duct extending between at least one room of the building and the exterior thereof and in communication with the room through a passageway for effecting a flow of air through the duct, a device for controlling the flow of air through the passageway into the duct comprising a frame positioned adjacent the walls defining the passageway, a damper pivotally mounted on said frame and capable of precluding the flow of air through the passageway when in an obstructing position relative thereto, means pivotally mounting said damper on said frame for movement between said obstructing position and a non-obstructing position, electrically operated means for effecting pivotal movement of said damper from said obstructing to said non-obstructing position, an electrical circuit for supplying electrical energy to said electrically operated means, a switch for permitting the flow of current through said circuit when said switch is in a closed position, and means for maintaining the flow of current through said circuit for a predetermined period of time after the switch is opened.
3. In a building which includes a ventilation duct extending between at least one room of the building and the exterior thereof and in communication with the room through a passageway for effecting a flow of air through the duct, a device for controlling the flow of air through the passageway into the duct comprising a frame positioned adjacent the walls defining the passageway, a damper pivotally mounted on said frame and capable of precluding the flow of air through the passageway when in an obstructing position relative thereto, means pivotally mounting said damper on said frame for movement between said obstructing position and a non-obstructing position, and selectively operable means for effecting pivotal movement of said damper between said obstructing and said non-obstructing positions, said selectively operable means including an electrically powered motor having a driven shaft, a pulley coupled to said shaft and adapted to be rotated thereby, an elongated cord connected at one end to said pulley so as to be coiled on said pulley when said pulley is rotated, said cord being connected at its other end to said damper so as to move said damper to said non-obstructing position when said cord is so coiled, an electrical circuit for supplying current to said motor, and a control switch within said circuit for controlling the flow of current therethrough.
4. A device in accordance with claim 3, wherein said motor is a clutch motor which is adapted to maintain a torque on said pulley when said damper is in the nonobstructing position.
References Cited UNITED STATES PATENTS 3,130,908 4/1964 Henne 98-33 X 3,150,584 9/1964 Allander 9833 LLOYD L. KING, Primary Examiner.