US1734545A

US1734545A - Means for delivering preheated air to combustion chambers

Info

Publication number: US1734545A
Application number: US243900A
Authority: US
Inventors: Gerrit Van Daam
Original assignee: Individual
Current assignee: Individual
Priority date: 1927-12-31
Filing date: 1927-12-31
Publication date: 1929-11-05
Anticipated expiration: 1946-11-05

Description

G. VAN DAAM Nov. 5, 1929.

1,734,545 MEANS FOR DELIVERING PREHEATED AIR TO COMBUSTION CHAMBERS Filed Dec. 31, 1927 g 4 J )l p n .Q r 2 m a emufl/ w r a E? 7 I w J 1 I Q n a. r 6 6 0 Patented Nov. 5, 1929 ennnrr VAN-,DAAM, or BUFFALO, NEW YoRx MEANS FOR nnmvnnrnernnnna'rnn AIR ro COMBUSTION CHAMBERS Application filed December'ifl, 1927. Serial No. 243,900.

My invention relates to delivering preheated air to combustion chambers, andis especially applicable to the combustion of coal where the unburned gases rise from the fuel bed and are mixed with the preheated air delivered thereto to facilitate the combustion of said gases.

The invention also comprises the control of the flow of air to be preheated and delivered to the combustion chamber in order to meet the conditions of the fuel bed and the temperature of the combustion chamber 'so that when the combustion chamber is relativelycold the flow of air will be restricted and as the chamber becomes heated the how of air will be relatively increased.

Referring to the drawings which illustrate merely by way of example, suitable means for effecting the invention Fig. 1 is a side elevation of the air heating element.

Fig. 2 is a longitudinal central section of same.

Fig. 3 is an elevation of the discharge end.

Fig. 4 is an elevation of the inlet end.

Fig. 5 is a detail in part section on an enlarged scale of the thermostat control unit.

Fig. 6 is a similar view of a modification.

Fig. 6 is a cross-section of same.

Similar numerals refer to similar parts hroughout the several views.

The heating element or body8 is preferably an integral casting in helical formation, but provided with an axial reinforcing extension 9 integral with the spiral. The spiral is cast with double

helical walls

10 and 11 forming a space 12 between these walls which provides a helical passage in annular cross-section from one end to the other. The inner space 13 enclosed in the inner wall 11 is a closed air space.

The device is secured at the inlet end to the door 14 of the combustion chamber and extends therefrom into the combustion chamber above the fuel bed.

The means for securing the heating ele ment to the doo-ror wall of the combustion chamber comprises the flanged element 15 Y which is threaded on to the nozzle 16 of the heating element. The flange 17 engages the inner face of the door 14 or wall of the coinbustion chamber. The element 15 is provided with the threaded nozzle formation 18 which extends through the door 14 or wall of the combustion ch amber, and receivesthe threaded end of the inlet formation or head 19, and forms a clamp therewith.

The discharge end of the heating element is provided with the cap 20 threaded thereon and having a series of air discharge vents 21.

Any suitable thermostat controlled valve is provided for automatically controlling the inlet of air to element 8.

InFig. 2 is shown a strip 28 secured to the inner recessed side of element 15, and to which is secured the valve rod 24 carrying the valve 25. This rod 24 is responsive to changes of temperatureto expand or contract to operate the valve25, sothat a greater supply ofair is admitted to the element 8, as its temperature increases.

In accordance with the arrangement shown in Fig. 5, a cap 22, provided withthe peripheral inlet ports 23 is'disengageably secured to the inner side of element 15. Through the endof the cap 22 projects the axially extending and movable stem or spindle 24; to the innerend of which is secured the valve 25, controlling the passage of air into the heating element 8. A helical bimetallic thermostat element 26 is secured at oneend to the valve stem or'spindle 24 near its outer end, and at its other end to the cap 22. As'this helix is within the passage of the heating element, it responds to variations of temperature to control the valve.

In the modification shown in Figs. 6 and 6 the bi-inetallic thermostat element 27 is in the form of a flat ribbon bent into a spiral; one end secured to a stationary support, the

other end secured to the spindle or valve stem 28, so that the action is to rotatethe spindle instead of moving it longitudinally. The rotating spindle 28 mo es the valve 29 to bring its ports 30 into and out of register with ports 31.

It will be noted that, in accordance with this arrangement, the valve and its thermostat control forms with the cap 22 a selfcontained unit which is readily and disengageably secured in position.

It will be noted that the annular and helical air passage-way 12, confined between the

walls

10 and 11, is of comparatively narrow cross-section and is almost entirely surrounded by the products of combustion in the combustion chamberand, due to its c'omparatively long and tortuous course, the air passtherethrough is heated approximately to the temperature of the combustion chamber before discharging through the vents 21.

hat I claim is 1. An air heating element for combustion chambers, comprising a body providing an annular air passage in helical formation extending from one end of said element to the other, and provided with an air inlet atone end and air discharge vents at the other end and means for supporting said element at its inlet end with the discharge vents-delivering to the combustion chamber.

2. In a. device of the character described, the combination of a heating element comprising two concentric tubes in helical for mation, having an axial reinforcing extension integral therewith and forming a passage between the wallsof said'tubesfrom one end of the element to the other, and provided with an inlet at one end and discharge vents at the other end and means for supporting the element at its inlet'end.

3. In a device of the character described, the combination of a heating element comprising two concentric tubes in helical formation forming a passage between the walls of said tubes from one end'of the element to the other, and provided with an inlet at one end and discharge vents at the other'e'nd, means for supporting the element at its inlet end, and a self-containing thermostat controlled valve unit disengageably secured in the inlet passage of the heating element.

l. In a device of the character described, the combination of a heating element comprising two concentric tubes in helical formation, providing a passage between the walls of said tubes from one end of the element to the other, and provided with an inlet at one end and discharge vents at the other end, means for supportingthe element at its inlet end, and a self-containing valve controlling thermostat unit disengageably secured in the air intake passage to the heatingunit.

5. In a device of the character'described, the combination of a heating element comprising two concentric tubes in helical formation, providing a passage between the walls of said tubes from one end of the elen't to the other, and provided with an inlet at one end and discharge vents at the other end, means for supporting the element at its inlet end, anda valve controlling thermostat unit, comprising an 'apertured ca'p,a valve, a valve spindle and abi-Inetallic coil associated with the cap, said cap being disengageably secured in the inlet passage of the heating element.

6. In a device of the character described, the combination of a heating element comprising two concentric tubes in helical formation, providing a passage between the walls of said tubes from one end of the element to the other, and provided with an inlet at one end and discharge vents at the other end,

means for supporting the element at its inlet end, comprising a flanged element threaded Onto said inlet end and an air intake head threaded onto the fiangedelement to form a clamp with a supporting wall.

7. Ina device of the character described, the combination of a heating element comprising two concentric tubes in helical formation, providing a passage between the walls of said tubes from one end of the element to theother, and provided with an inlet at one end and discharge vents at the other end, means for supporting the element at its inlet end, and a self-containing valve controlling thermostat -unit, comprising an apertured cap, a valve, a valve spindle and a bimetallic coil for rotating the spindle associated with the cap, said cap being disengageably secured in the inlet passage of the heating element.

GERRIT VAN DAAM.