Thermal sensor

Claim 2

A thermal sensor adapted for use in an internal combustion engine induction system having an inlet for air at ambient temperature and an inlet for heated air, valve means controlling air flow through said inlets, a vacuum motor positioning said valve means to allow heated air flow in direct relation and ambient temperature air in inverse relation with a vacuum signal and having a fitting for receiving the vacuum signal, and a source of vacuum, said thermal sensor comprising first and second shells defining a chamber therebetween, at least one of said shells being adapted for exposure to the air flow in said induction system downstream of said inlets and being formed of metal to provide rapid heat transfer to and from said chamber, fitting means adapted to connect said chamber to said vacuum source to create a subatmospheric pressure in said chamber, one of said shells having an air bleed opening into said chamber for admitting air to increase the pressure therein and further having a valve seat surrounding said air bleed within said chamber, a spherical valve ball formed of non-hygroscopic plastic associated with said valve seat for varying air flow through said air bleed to create a controlled vacuum signal within said chamber, and a bimetal strip disposed within said chamber and biasing said ball toward said valve seat with a force that varies inversely with the temperature created by heat transfer through said metal shell to cause said ball to admit air through said air bleed to create a vacuum signal which varies inversely with such temperature, said fitting means being further adapted to connect said chamber to said vacuum motor fitting to deliver said vacuum signal to said vacuum motor whereby said vacuum motor may position said valve means to allow increased heated air flow and decreased ambient temperature air flow when the induction air flow downstream of said inlets is below a predetermined temperature and to allow decreased heated air flow and increased ambient temperature air flow when the induction air flow downstream of said inlets is above the predetermined temperature.

Claim 3

A thermal sensor adapted for use in an internal combustion engine induction system having an inlet for air at ambient temperature and an inlet for heated air, valve means controlling air flow through said inlets, a vacuum motor positioning said valve means to allow heated air flow in direct relation and ambient temperature air in inverse relation with a vacuum signal and having a fitting for receiving the vacuum signal, and a source of vacuum, said thermal sensor comprising first and second shells defining a chamber therebetween, at least one of said shells being adapted for exposure to the air flow in said induction system downstream of said inlets and being formed of metal to provide rapid heat transfer to and from said chamber, fitting means adapted to connect said chamber to said vacuum source to create a subatmospheric pressure in said chamber, one of said shells having an air bleed opening into said chamber for admitting air to increase the pressure therein and further having a valve seat surrounding said air bleed within said chamber, a spherical valve ball formed of acetal resin associated with said valve seat for varying air flow through said air bleed to create a controlled vacuum signal within said chamber, and a bimetal strip disposed within said chamber and biasing said ball toward said valve seat with a force that varies inversely with the temperature created by heat transfer through said metal shell to cause said ball to admit air through said air bleed to create a vacuum signal which varies inversely with such temperature, said fitting means being further adapted to connect said chamber to said vacuum motor fitting to deliver said vacuum signal to said vacuum motor whereby said vacuum motor may position said valve means to allow increased heated air flow and decreased ambient temperature air flow when the induction air flow downstream of said inlets is below a predetermined temperature and to allow decreased heated air flow and increased ambient temperature air flow when the induction air flow downstream of said inlets is above the predetermined temperature.

Claim 4

A thermal sensor adapted for use in an internal combustion engine induction system having an inlet for air at ambient temperature and an inlet for heated air, valve means controlling air flow through said inlets, a vacuum motor positioning said valve means to allow heated air flow in direct relation and ambient temperature air in inverse relation with a vacuum signal and having a fitting for receiving the vacuum signal, and a source of vacuum, said thermal sensor comprising first and second shells defining a chamber therebetween, at least one of said shells being adapted for exposure to the air flow in said induction system downstream of said inlets and being formed of metal to provide rapid heat transfer to and from said chamber, fitting means adapted to connect said chamber to said vacuum source to create a subatmospheric pressure in said chamber, one of said shells having an air bleed opening into said chamber for admitting air to increase the pressure therein and further having a valve seat surrounding said air bleed within said chamber, a spherical valve ball formed of acetal resin associated with said valve seat for varying air flow through said air bleed to create a controlled vacuum signal within said chamber, and a bimetal strip disposed within said chamber and biasing said ball toward said valve seat with a force that varies inversely with the temperature created by heat transfer through said metal shell to cause said ball to admit air through said air bleed to create a vacuum signal which varies inversely with such temperature, said fitting means being further adapted to connect said chamber to said vacuum motor fitting to deliver said vacuum signal to said vacuum motor whereby said vacuum motor may position said valve means to allow increased heated air flow and decreased ambient temperature air flow when the induction air flow downstream of said inlets is below a predetermined temperature and to allow decreased heated air flow and increased ambient temperature air flow when the induction air flow downstream of said inlets is above the predetermined temperature.

Claim 5

A thermal sensor adapted for use in an internal combustion engine induction system having an inlet for air at ambient temperature and an inlet for heated air, valve means controlling air flow through said inlets, a vacuum motor positioning said valve means to allow heated air flow in direct relation and ambient temperature air in inverse relation with a vacuum signal and having a fitting for receiving the vacuum signal, and a source of vacuum, said thermal sensor comprising first and second shells defining a chamber therebetween, at least one of said shells being adapted for exposure to the air flow in said induction system downstream of said inlets and being formed as a metal die casting having a plurality of fins extending therefrom to provide rapid heat transfer to and from said chamber, fitting means adapted to connect said chamber to said source to create a subatmospheric pressure in said chamber, one of said shells having an air bleed opening into said chamber for admitting air to increase the pressure therein and further having a valve seat surrounding said air bleed within said chamber, a spherical valve ball formed of non-hygroscopic plastic associated with said valve seat for varying air flow through said air bleed to create a controlled vacuum signal within said chamber, and a bimetal strip disposed within said chamber and biasing said ball toward said valve seat with a force that varies inversely with the temperature created by heat transfer through said metal shell to cause said ball to admit air through said air bleed to create a vacuum signal which varies inversely with such temperature, said fitting means being further adapted to connect said chamber to said vacuum motor fitting to deliver said vacuum signal to said vacuum motor whereby said vacuum motor may position said valve means to allow increased heated air flow and decreased ambient temperature air flow when the induction air flow downstream of said inlets is below a predetermined temperature and to allow decreased heated air flow and increased ambient temperature air flow when the induction air flow downstream of said inlets is above the predetermined temperature.

Claim 6

A thermal sensor adapted for use in an internal combustion engine induction system having an inlet for air at ambient temperature and an inlet for heated air, valve means controlling air flow through said inlets, a vacuum motor positioning said valve means to allow heated air flow in direct relation and ambient temperature air in inverse relation with a vacuum signal and having a fitting for receiving the vacuum signal, and a source of vacuum, said thermal sensor comprising first and second shells defining a chamber therebetween, at least one of said shells being adapted for exposure to the air flow in said induction system downstream of said inlets and being formed as a metal die casting having a plurality of fins extending therefrom to provide rapid heat transfer to and from said chamber, fitting means adapted to connect said chamber to said source to create a subatmospheric pressure in said chamber, one of said shells having an air bleed opening into said chamber for admitting air to increase the pressure therein and further having a valve seat surrounding said air bleed within said chamber, a spherical valve ball formed of non-hygroscopic plastic associated with said valve seat for varying air flow through said air bleed to create a controlled vacuum signal within said chamber, and a bimetal strip disposed within said chamber and biasing said ball toward said valve seat with a force that varies inversely with the temperature created by heat transfer through said metal shell to cause said ball to admit air through said air bleed to create a vacuum signal which varies inversely with such temperature, said fitting means being further adapted to connect said chamber to said vacuum motor fitting to deliver said vacuum signal to said vacuum motor whereby said vacuum motor may position said valve means to allow increased heated air flow and decreased ambient temperature air flow when the induction air flow downstream of said inlets is below a predetermined temperature and to allow decreased heated air flow and increased ambient temperature air flow when the induction air flow downstream of said inlets is above the predetermined temperature.

Claim 7

A thermal sensor adapted for use in an internal combustion engine induction system having an inlet for air at ambient temperature and an inlet for heated air, valve means controlling air flow through said inlets, a vacuum motor positioning said valve means to allow heated air flow in direct relation and ambient temperature air in inverse relation with a vacuum signal and having a fitting for receiving the vacuum signal, and a source of vacuum, said thermal sensor comprising a lower shell having an upturned rim, an upper shell having a downturned rim received within said lower shell rim, said shells defining a chamber therebetween, at least one of said shells being adapted for exposure to the air flow in said induction system downstream of said inlets, said shells being formed as sheet metal stampings to provide rapid heat transfer to and from said chamber, said lower shell having a first fitting adapted to connect said chamber to said vacuum source to create a subatmospheric pressure in said chamber, said upper shell having a threaded aperture, a plug adjustably received in said aperture and having an air bleed opening into said chamber for admitting air to increase the pressure therein and further having a tapered annular valve seat surrounding said air bleed within said chamber, a spherical valve ball formed of acetal resin associated with said valve seat for varying air flow through said air bleed to create a controlled vacuum signal within said chamber, and a bimetal strip having one end riveted to the underside of said upper shell within said chamber and having its free end disposed biasing said ball toward said valve seat with a force that varies inversely with the temperature created by heat transfer through said metal shells to cause said ball to admit air through said air bleed to create a vacuum signal which varies inversely with such temperature, said lower shell having a second fitting adapted to connect said chamber to said vacuum motor fitting to deliver said vacuum signal to said vacuum motor whereby said vacuum motor may position said valve means to allow increased heated air flow and decreased ambient temperature air flow when the induction air flow downstream of said inlets is below a predetermined temperature and to allow decreased heated air flow and increased ambient temperature air flow when the induction air flow downstream of said inlets is above the predetermined temperature.

Claim 8

A thermal sensor adapted for use in an internal combustion engine induction system having an inlet for air at ambient temperature and an inlet for heated air, valve means controlling air flow through said inlets, a vacuum motor positioning said valve means to allow heated air flow in direct relation and ambient temperature air in inverse relation with a vacuum signal and having a fitting for receiving the vacuum signal, and a source of vacuum, said thermal sensor comprising a lower shell having an upturned rim, an upper shell having a downturned rim received within said lower shell rim, said shells defining a chamber therebetween, at least one of said shells being adapted for exposure to the air flow in said induction system downstream of said inlets, said shells being formed as sheet metal stampings to provide rapid heat transfer to and from said chamber, said lower shell having a first fitting adapted to connect said chamber to said vacuum source to create a subatmospheric pressure in said chamber, said upper shell having a threaded aperture, a plug adjustably received in said aperture and having an air bleed opening into said chamber for admitting air to increase the pressure therein and further having a tapered annular valve seat surrounding said air bleed within said chamber, a spherical valve ball formed of acetal resin associated with said valve seat for varying air flow through said air bleed to create a controlled vacuum signal within said chamber, and a bimetal strip having one end riveted to the underside of said upper shell within said chamber and having its free end disposed biasing said ball toward said valve seat with a force that varies inversely with the temperature created by heat transfer through said metal shells to cause said ball to admit air through said air bleed to create a vacuum signal which varies inversely with such temperature, said lower shell having a second fitting adapted to connect said chamber to said vacuum motor fitting to deliver said vacuum signal to said vacuum motor whereby said vacuum motor may position said valve means to allow increased heated air flow and decreased ambient temperature air flow when the induction air flow downstream of said inlets is below a predetermined temperature and to allow decreased heated air flow and increased ambient temperature air flow when the induction air flow downstream of said inlets is above the predetermined temperature.