Air induction box

Claim 2

An air induction box having a primary air inlet adjacent one end portion for receiving a supply of primary air under pRessure from a supply duct and having an outlet for delivering air toward a point of use, a return air inlet in said box upstream of said outlet for delivering secondary air into the box, means within said box and responsive to the flow of primary air therethrough to induce a flow of secondary air into said box through said return inlet for mixture with said primary air and delivery out of said outlet, and means in said inlets and operable in response to temperature changes at the point of use to increase the rate of flow through one inlet and decrease the rate of flow through the other inlet, or vice versa, by substantially corresponding amounts and thereby maintain a substantially constant volume flow of mixed air out of said outlet, the improvement in said induction box comprising, a regulator module attached to and constituting a unit of said box, said module including: a. a support connected to said one end portion of said box downstream of the supply duct and upstream of said primary inlet and defining a passage establishing communication between the supply duct and the primary inlet, b. a damper mounted on said support and adjustable to various open positions with respect to said passage to vary the rate of flow therethrough, c. a reversible actuator mounted on said support and effective when operated to adjust said damper, and d. a control responsive to changes in pressure downstream of said damper for causing operation of said actuator as a function of such pressure changes thereby to maintain a substantially constant pressure between said damper and said primary inlet.

Claim 3

An air induction box as defined in claim 1 in which said regulator module is disposed within said box, said one end portion of said box including means adapted for attachment to said supply duct.

Claim 4

An air induction box as defined in claim 2 further including a heater disposed within said box between said last-mentioned means and said regulator module, said heater being activated in response to the flow rate through said return inlet increasing to a predetermined value and being operable when activated to raise the temperature of the primary air flowing through said primary inlet.

Claim 5

An air induction box as defined in claim 1 in which said regulator module is attached to the upstream end of said box and is disposed outside of the box.

Claim 6

An air induction box as defined in claim 4 in which said support comprises a plate covering the upstream end of said box, said passage extending through said plate and being defined in part by a pipe attached to said plate and connected to the supply duct.

Claim 7

An air induction box as defined in claim 1 in which said damper is mounted swingably in said passage, said reversible actuator comprising an expandible bellows mounted on said support and connected to swing said damper, said control also being mounted on said support and being operable to govern expansion of said bellows.

Claim 8

An air induction box as defined in claim 1 in which said damper comprises a resiliently yieldable diaphragm connected to said support and adapted to be flexed to different positions to cover different areas of said passage and vary the rate of flow therethrough, said actuator comprising a chamber sealed at one end by said diaphragm and communicating at its opposite end with the supply duct whereby the pressure in the supply duct is effective to flex said diaphragm.

Claim 9

An air induction box as defined in claim 1 further including a heater disposed within said box upstream of said primary air inlet, said heater being activated in response to the flow rate through said return inlet increasing to a predetermined value and being operable when activated to raise the temperature of the primary air flowing through said primary inlet.

Claim 10

An air induction box adapted for connection at one end to a supply duct and having a primary air inlet near said one end for receiving primary air under pressure from the supply duct, said box having an outlet near its opPosite end for delivering air toward a point of use, a return air inlet in said box upstream of said outlet for delivering secondary air into the box, means within said box and responsive to the flow of primary air therethrough to induce a flow of secondary air into the box through said return inlet for mixture with said primary air and delivery out of said outlet, and means in said inlets and operable in response to temperature changes at the point of use to increase the rate of flow through one inlet and decrease the rate of flow through the other inlet, or vice versa, by substantially corresponding amounts and thereby maintain a substantially constant volume flow of mixed air out of said outlet, the improvement in said induction box comprising, a regulator module attached to and constituting a unit of said box, said regulator module including: a. a support disposed inside of said box between said one end and said primary air inlet and defining a passage establishing communication between the supply duct and the primary air inlet, b. a damper mounted on said support and within said box and adjustable to various positions opening different areas of said passage to vary the rate of flow therethrough, c. a reversible actuator mounted on said support and within said box and effective when operated to adjust said damper, and d. a control mounted on said support and within said box and responsive to changes in pressure downstream of said damper for causing operation of said actuator as a function of such pressure changes thereby to maintain a substantially constant pressure between said damper and said primary inlet.

Claim 11

An air induction box adapted for connection at one end to a supply duct and having a primary air inlet near said one end for receiving primary air under pressure from the supply duct, said box having an outlet near its opPosite end for delivering air toward a point of use, a return air inlet in said box upstream of said outlet for delivering secondary air into the box, means within said box and responsive to the flow of primary air therethrough to induce a flow of secondary air into the box through said return inlet for mixture with said primary air and delivery out of said outlet, and means in said inlets and operable in response to temperature changes at the point of use to increase the rate of flow through one inlet and decrease the rate of flow through the other inlet, or vice versa, by substantially corresponding amounts and thereby maintain a substantially constant volume flow of mixed air out of said outlet, the improvement in said induction box comprising, a regulator module attached to and constituting a unit of said box, said regulator module including: a. a support disposed inside of said box between said one end and said primary air inlet and defining a passage establishing communication between the supply duct and the primary air inlet, b. a damper mounted on said support and within said box and adjustable to various positions opening different areas of said passage to vary the rate of flow therethrough, c. a reversible actuator mounted on said support and within said box and effective when operated to adjust said damper, and d. a control mounted on said support and within said box and responsive to changes in pressure downstream of said damper for causing operation of said actuator as a function of such pressure changes thereby to maintain a substantially constant pressure between said damper and said primary inlet.

Claim 12

An air induction box as defined in claim 9 further including a heater disposed within said box upstream of said primary inlet, said heater being activated in response to the flow rate through said return inlet increasing to a predetermined value and being operable when activated to raise the temperature of the primary air flowing through said primary inlet.

Claim 13

An air induction box having a primary air inlet adjacent one end for receiving a supply of primary air under pressure from a supply duct and having an outlet for delivering air toward a point of use, a return air inlet in said box upstream of said outlet for delivering secondary air into the box, means within said box and responsive to the flow of primary air therethrough to induce a flow of secondary air into said box through said return inlet for mixture with said primary air and delivery out of said outlet, and means in said inlets and operable in response to temperature changes at the point of use to increase the rate of flow through one inlet and decrease the rate of flow through the other inlet, or vice versa, by substantially corresponding amounts and thereby maintain a substantially constant volume flow of mixed air out of said outlet, the improvement in said induction box comprising, a regulator module attached to and constituting a unit of said box, said module including: a. a support attached to and covering said one end of said box upstream of said primary inlet and including a pipe adapted for connection to the supply duct and defining a passage establishing communication between the supply duct and the primary inlet, b. a damper mounted on said support outside of said box and adjustable to various open positions with respect to said passage to vary the rate of flow therethrough, c. a reversible actuator mounted on said support outside of said box and effective when actuated to adjust said damper, and d. a control on said support and responsive to changes in pressure downstream of said damper for causing operation of said actuator as a function of such pressure changes thereby to maintain a substantially constant pressure between said damper and said primary inlet.

Claim 14

An air induction box having a primary air inlet adjacent one end for receiving a supply of primary air under pressure from a supply duct and having an outlet for delivering air toward a point of use, a return air inlet in said box upstream of said outlet for delivering secondary air into the box, means within said box and responsive to the flow of primary air therethrough to induce a flow of secondary air into said box through said return inlet for mixture with said primary air and delivery out of said outlet, and means in said inlets and operable in response to temperature changes at the point of use to increase the rate of flow through one inlet and decrease the rate of flow through the other inlet, or vice versa, by substantially corresponding amounts and thereby maintain a substantially constant volume flow of mixed air out of said outlet, the improvement in said induction box comprising, a regulator module attached to and constituting a unit of said box, said module including: a. a support attached to and covering said one end of said box upstream of said primary inlet and including a pipe adapted for connection to the supply duct and defining a passage establishing communication between the supply duct and the primary inlet, b. a damper mounted on said support outside of said box and adjustable to various open positions with respect to said passage to vary the rate of flow therethrough, c. a reversible actuator mounted on said support outside of said box and effective when actuated to adjust said damper, and d. a control on said support and responsive to changes in pressure downstream of said damper for causing operation of said actuator as a function of such pressure changes thereby to maintain a substantially constant pressure between said damper and said primary inlet.