US1676677A - Dental flask - Google Patents

Description

July 10, 1928.

M. L. AXELROD DENTAL FLASK Filed Jun'za, 192e Patented July l0, 1928.

Unirse srares l '1,676,677 ATEN'r OFI-fics. f

MEYER L. AXELROD, OF CILLEVJLAND,` OHIO, ASSGNOR TO OHO CHEMICAL & MANU- FACTURINGCOMPANY, OF CLEVELAND, OHIO, A CORPORATION OF OHIO.

DENTAL mask.

Application led June 28,

r This invent-ion relates to flasks for use by dentists and dental laboratories for molding and vulcanizing rubber, molding and curing bakelite, and similar purposes. and its chief object is to provide a self-heating flask of simple and durable construction and reliable operation which can be manufactured at reasonable cost. Another object is to provide a self-heating flask in which the temperature is under thermostatic control so that a predetermined temperature can be maintained without attention by the operator, thereby preventing injury to the mold contents by overheating. To these and other ends the invention comprises the novel features hereinafter described.

One forni ot my improved flask is illustrated in the accompanying drawings, in which Fig. l is a perspective view oit the complete lask. I

Fig. 2 is a plan view (on .line 2 2, Fig. 8) ot' the lower part of the iiask, with the electrical heating element or coil in dotted lines.

Fig. 3 is a central cross section on the plane indicated at 3--3, Fig. 1.

F ig. 4 is a diagram showiiig the preferred method of connecting the heating elements with a source of current.

The flask shown comprises separable upper and lower body portions 10, 1l. The upper portion 10 has a removable cover provided with ears 14 to receive screws l5 eX- tending through aligned ears 16 into bosses 17 on the lower part to hold the two parts together under pressure. The lower body portion -11 has a removable bottom 18 provided with ears 19 aligned with the bosses 17 to receive the screws 21 by which the said bottom 18 is held in place. To insure proper assembly ot the parts the lower is provided with recesses 22 alongside of the bosses 17, Fig. 2, to receive closely tit-ting fingers 23 on the upper part, as will be readily understood.

The heating elements 24, 25, are housed in the cover 12 and bottom 18. which are made hollow for the purpose and are closed by means of inner plates 26, 27., removably secured by screws 28. The terminals of `the lower heating element are brought out to contact pins 29 carried by but insulated :trom a bracket 8() mounted on the bottom 18. The cover 1.2 may have a central hol- 1926. Serial No. 118,941, 1

low rib 31 to house a removable thermostat 32 carried by but insulated from said rib. One end ot the thermostat (which is 'shown as the conventional two-metal type) is connected to the contact-.pin 33 and theother is adapted to engage a contact 34 connected with one terminal ot the heating element 24. The other terminal oi the heating element is connected to contact pin 35, as clearly indicated in Fig. 4. The pins 33,' 35 are carried by but insulated from a bracket 36 mounted on the cover 12. The heating elements 24, 25 are embedded in refractory insulating bodies 37, which may adhere to or be otherwise secured to the plates 26, 27.

Fig. 4 illustrates diagrammatically a convenient way ot connecting the heating elements to the source of current, not shown. ln this ligure, 40 represents a cord having two conductors 41, 42, connected to terminal pins 43, 44, carried by an insulating plug,7 not shown. Conductors 4l and 42 are connected at their other ends to sockets 45, 46, carried by insulating caps, not shown, which latter also carry sockets 47, 48 connected together by an insulated flexible conductor 49. lt will be apparent that when the pins 43, 44 are connected with the terminals of a source of current and pins 29, 33, 85 are plugged into the caps carrying the sockets 45, 46, 47, 48, current will flow through the thermostat and heating elements in series. It' the temperature to which the thermostat is subjected rises above a predetermined point the thermostat tleXes and opens the circuit, closing it again when the temperature Jr'alls. In this way a substantially constant temperature is maintained, as will be readily understood. For simplicity a non-adjustable thermostat is shown, but it will be understood that the invention is not limited to that type. In order to vary the temperature with the type shown it is necessary to remove the cover plate 2ok by taking out the screws, whereupon the thermostat may be removed and another substituted, to maintain a higher or lower temperaturgLas may be desired.

he pressure needed in vulcanizing or curing can be applied by setting up the screws 15. Preferably, however, these screws are used merely to hold the parts together, the necessary pressure being applied by means of any suitable press, not shown. For this purpose the bottom of the flask is made flat, as indicated, Eand the top may be provided with `.radial ribs 38, lush with the thermostat housing 3l, to distribute the pressure and there avoid breakage of the cover, as will be readily understood: The screws 15 can then be set up and the flask removed, or it can remain in the press during part or all of the period of heating.

My improved flask is convenient by reason of the fact that not only can the two halves be separated, as is customary, but also the bottom andtop can be removed. Moremimportant, however, is itsself-heating feature, whichadapts vit to vulcanization by dry heat instead oi by,steam.l This 'feature is especially important in making bakelite dentures, as described. in my copending application Serial No. 73,60l, liled December 7, 1925, which the `hakelite must be kept dry while being` curedf It is to be understood that the invention is not limited to the specific construction herein illustrated and described but can be embodied in other forms without departure from its spirit.

l claim- A self-heating dental iiask composed of separable upper and lower sections having hollow upper and lower walls, electrical heating elements housed in the top of t-he upper section and the bottom of the lower section,

means for connecting the heating elements with Va source of current, and a thermostat` MEYER L. AXELROD.

Images