US2017097A - Laboratory burner - Google Patents

Description

0m. 15, 1935. c. s. HORNBERGER 2,017,097

LABORATORY BURNER Filed Dec. 21, 1931 liuenzofi Ca/A 5. 1707 71601 927 a W Patented Oct. 15, 1935 UNITED STATES LABORATORY BURNER Carl S. Hornberger, Glen Ellyn, Ill., assignor to Central Scientific Company, a corporation of Illinois Application December 21, 1931, Serial No. 582,248

3 Claims.

R to provide a base for such burners having unusual stability; that can be supported in an elevated position on a ring Without employing the customary wire gauze; that can be tilted almost 90 from the horizontal while supported on a ring without any danger of its sliding off; that provides an enlarged mixing chamber for the gas and air; that has a gas jet passage designed to effect a minimum retardance of the velocity of the jet; and that is cheap to manufacture, durable, and simple in form.

Further and other objects and advantages of the invention will become apparent as the disclosure proceeds and the description is read in conjunction with the accompanying drawing, in which Fig. 1 is a series of diagrammatic views illustrating the versatility of the novel burner base;

Fig. 2 is a perspective view showing a preferred form of the invention associated with a supporting ring, it being noted that the burner is firmly seated on the ring although the latter is tilted at a steep angle;

Fig. 3 is a transverse, sectional view taken through the center of the burner;

Fig. 4 is a bottom plan view of the base, a supporting ring being shown in dotted lines;

Fig. 5 illustrates a modified base; and

Fig. 6 shows a modified form of burner tube.

Bunsen burners have been used for years in scientific laboratories as a source of heat. There is probably no laboratory in the country that is not equipped with one or more Bunsen burners.

To those familiar with laboratory routine, the ordinary Bunsen burner has several distinct disadvantages. Like other laboratory burners, Bunsen burners are ordinarily provided with circular bases that furnish only a fair degree of stability. When it is desired to hold the burner in an elevated position in order to heat a particular piece of apparatus, it is customary to set up a ring stand and set the burner on a piece of wire gauze placed over the ring.

If the particular heating job required to be accomplished demands that the burner be held at an angle, it is necessary to clamp the burner in such position.

If the burner, whether it be a Bunsen burner or some other type, is merely seated upon a wire gauze placed over a ring, it often happens that the accidental touching of the gas hose will cause the burner to fall from its support. This tendency is aggravated by the weight of the hose itself. One such experience while performing a laboratory experiment is sufficient to demonstrate the need for a more stable burner base.

The present invention provides a base, suitably adapted to be used with any of the many types of laboratory burners, which is so constructed that it can be placed upon a ring or disk support and will be firmly held thereon by gravity even though the support be tilted at an angle approaching ninety degrees.

In the preferred form of the invention, the base assumes an H-shape and comprises two parallel 15 bar like members or legs l0 and H, integrally connected by a bridge l2. Adjacent each end of the legs ill and H are depending feet it, l4, l5 and Hi, the inner surfaces of which are equidistant from the geometric center of the base.

A laterally'extending hose nipple llprojects horizontally from the center of the base and is preferably ribbed as at ill to firmly grip the gas hose.

Rising from the center of the bridge is a boss 25 I9 bored at 2!] to receive the burner tube or stack H. The bore ends abruptly at 22 to provide a seat for the tube.

An enlarged bore 23 is made from the bottom of the base in axial alinement with the burner tube. 30 The upper end of this bore is gradually tapered or filleted as at 24 to merge with the shoulder 22 of the upper bore.

Gas is introduced into the burner through a passage 25 bored into the hose nipple I! which 35, communicates with the mixing chamber 26 (which comprises the bore 23) by an inclined restricted passage 21. It has been shown by experiment that the best results are obtained when the passage Zlis so inclined that it directs the 40 incoming gas through the upper portion of the mixing chamber 26 and strikes the tube 2! at the greatest possible obtuse angle. This is so because the velocity of the gas" stream is reduced in proportion to the angle at which it strikes the tube or opposing wall, so that if the angle of incidence is the greatest possible obtuse angle, there will be no appreciable reduction of velocity. In consequence, a hotter and more forceful flame may be secured.

The burner tube 2| may be longitudinally slit for a short distance as at 28 and then transversely slit for a fractional portion of its circum- Terence as at 29 to provide the necessary resilience for inserting the tube in its socket.

V The illustration in Fig. 1 shows how easily this It is obvious that 4 to an H-base. For example, a three-legged base,

The amount of air allowed to mix with the incoming fuel is controlled by an adjustable closure which may take the form of a lever 30 pivoted at one end to a boss 3| by a screw 32. The particular shape of the lever shown in the draw,- ing has the advantage of providing 'a'better rate of admission of air when thelever is adjacent its closed position. r r The base is preferably cast in iron or other dense metal in order to give it relatively great mass. This fact in conjunction with the partic' ular form of the base and its relatively low center of gravity gives unusual stability to the burner.

An inspection of the drawing will clearly indicate the manner in which this Hfform of base may be supported 'on a ring stand at various angles. Referring to Fighlfor example, there is shown a distilling flask being heated at its base by two burners and at its neck by a third burner. This furnishes an apt illustration of the utility of the novel base of this invention. Quite often in distilling liquids, it is desirable to employ two burners for heating the liquid. and it is impossible to place twoordinary Bunsen burners in position to heat the liquid without clamping them in tilted position. With the improved base, however, they may be placed upon tilted rings in the desired position and will be held in place solely by gravity. j 7 7 In'the sameillustration, it is ofteri desir'able to heat the neck of the distilling flask in order to preventcondensation taking place along the walls of the neck. It is almost essential that a burner be held at elevated and tilted position to accomplish the necessary heating of the neck.

particular job of-heating may be accomplished byf he present invention. t I The three other'diagrammatic illustrations in ;Fig. 1-apipearing on the right of the distilling apparatus show that it makes 'no difference whether the legs of'the base arejhorizontal or vertical, or whether a soliddisk is used in place of a customary ring. I I I he invention is not limited as shown in Fig. 5 may be used although it does not havethe same degree of stabilitythat the H-base possesses. Likewise the base may be cast in the form of an 'X'or Z or any other shape that would furnish the desired stability.

In practice, the burner bases are made in sizes corresponding to standard ring diameters. These range from one to seven inchesfthat is one inch, two inches, three inches, etcj In a central draft burner'of the type herein disclosed, it hasbeenfound that the enlarged bore" 23 which forms the -mixing'chambe'r 26 constitutes the difference between failure and success'when gas of 700 B. T. UJSper-cubicft.

and up is used. t

' The shoulder formed at the junction of the tube bore 20 and the enlarged bore 23 has the effect of preventing molten or gummy substances 5 whichimay form on the interior of the burner Q purpose of this is to stabilize the flame, especially when highB. T. U. gas is being used, although it is not fully understood how the stabilization is actually accomplished. Apparently the inwardly directed walls of the tube set up eddy currents producing a better admixture of fuel and air, but

irrespective of theory, a more stable flame is secured.

It will be understood that the above specific description of preferred and modified forms of claims.

What I claim, therefore, is:

1." A laboratory burner adapted to be supported in an elevated position on a ring, said burner having a basecomprising two spaced parallel bar-like members joined at their mid-section by a bridge, the bottom faces of said members being substantially flat and coplanar, and supporting means on the base comprising depending feet on thebar like members having supporting faces Which' are equidistant from the center of the bridge and are adapted to engage an edge of the ring and hold the burner'in place when the ring is tilted from the horizontal.

- 2. A laboratory'burner adapted to be supported in an elevated position on a ring, said burner having a base comprising two spaced parallel bar-like members joined at their mid-section'by abridge, said bridge having a' vertical bore to receive a burner tube, a valve for regulating the admittance of air through the bottom of the bore, said bridge being raised above the plane of the bottom of the bar-like membersto afford ready admittance of air to the bore, the bottom faces of said members being substantially flat and coplanar, and supporting means on the base comprising depending feet on the bar-like members having supporting faces which are equidistant from the center of the bridge and are adapted to engage an edge of the ring and hold the burner in place when the ring is tilted from the horizontal.

3. A laboratory burner having an extended base having portions with flat coplanar bottom surfaces adapted to seat on the top surface of a supporting ring or disk, said portions having feet depending therefrom having side faces equidistant from the center of the base and adapted to engage a side face of said ring or disk to hold the burner in place when the ring or disk is tilted from the horizontal.

' CARL S. HORNBERGER.

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