US401391A

US401391A - Regulating-valve for dental vulcanizers

Info

Publication number: US401391A
Authority: US
Publication date: 1889-04-16
Anticipated expiration: 1906-04-16

Description

(No Model.)

. L. STUCK. REGULATING VALVE FOR DENTAL VULOANIZERS.-

No. 401,391. Patented Apr. 16, 1889.

N PUERS. MwUtMgraphor. WllWglcn. D, C.

UNITED STATES PATENT LEVI STUCK, OF HART, MICHIGAN.

SPECIFICATION forming part of Letters Patent No. 401,391, dated April 16, 1889. Application filed May 1'7, 1888. Serial No. 274,228. (No model.)

To aZZ whom it may concern.-

Be it known that I, LEVI STUCK, of Hart, in the county of Oceana and State of Michigan, have invented certain new and useful Improvements in Regulating-Valves for Dental Vulcanizers; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it pertains to make and use it, reference being had to the accompanying drawing, which forms part of this specification. 7

- My invention relates to an improvement in regulating-valves for dental vulcanizers; and it consists in the combination of a dental vulcanizer, a cylinder which is connected thereto and which has a valveseat in its bottom, and a blow-off pipe with a spring-actuated valve, a graduated stem connected with the valve, and an adjustable screw cap or cover for the cylinder, as will be more fully described here inafter.

The object of my invention is to provide a regulatingwalve for dental vulcanizers which will open at a certain regulated pressure and begin to allow the steam to escape, so as to give notice to the operator that the vulcanizing point has been reached, and thus notify him to note the time from the opening until the pressure of the steam has reached the highest regulated point, and thus dispense with the necessity of keeping a close watch upon the thermometer connected to the vulcanizer, as has heretofore been the case.

The accompanying drawing represents a device which embodies my invention, the cylinder being shown in section.

A represents an ordinary vulcanizer, and B the cylinder, which is screwed into its top or at any other suitable point. Through the bottom of this cylinder is made a straight opening, so as to receive the guide E of the valve, and in the bottom of the cylinder is made a valve-seat upon which the valve 0 rests. The opening through the bottom of the sc1'ewthreaded portion of the cylinder is made straight, so as to correspond to the shape of the guiding portion of the valve which fits in this opening. When the pressure of the steam becomes sufficiently great to raise the valve from its seat against the pressure of the spring G, placed upon the valvestem H and regulating the pressure of the valve upon its seat, the steam escapes freely through the escape-pipe I, which extends from the bottom of the cylinder. The steam, in passing through the opening in the bottom of the cylinder, bears directly against the whole bottom of valve, and hence the valve will immediately allow the steam to escapeas soon as the regulated pressure has been reached.

The valvestem II projects through the screw-cover J of the cylinder, and is provided with a head, L, at its upper end, so as to enable the valve to be lifted from its seat by the operator whenever he so desires. In the valvestem are made a number of grooves, which form a graduated scale which represents the different pressures of steam which are to be used. The lowest groove represents the greatest pressure and the highest the least. The screw-cap is vertically adjustable upon the cylinder in relation to the graduations on the valve-stem, so that the valve can be set at any desired pressure. In proportion as the cap is unscrewed it rises upon. the valve-stem, and of course lessens the tension of the spring upon the valve accordingly. If one of the marks upon the stem indicates a pressure of 300, it is only necessary to move the cap until its upper edge coincides with this mark, and. then the steam will. blow off at this pressure.

After the plate has been placed in the vulcanizer and the cap has been adjusted to the pressure, say, of 300, the operator can go on about his business, and need pay no further attention to the vnleanizer, for when the heat reaches 300 the valve will open and the steam will begin. to escape. The escape of the steam does not indicate the safety-point, but simply serves as a notice to .the operator that the heat has reached 300 and that he is to compute the time from that moment. \Vith the constant escape of steam the rise in temperature is slightly retarded, so that it will take just about forty minutes for the heat to reach 330. The operator, knowing that it will take just forty minutes to reach 330, and that forty minutes are required to complete the vulcanizing of the plate, he can go on with his work in any part of the building after the steam once begins to blow ofl at 300 without paying any further attention to anything except the passage of time. At the end of forty minutes he will find that the heat has reached 330, when the plate will be perfectly finished.

Heretofore safety-valves have been applied to dental Vulcanizers; but they have served no other purpose than to prevent the pressure of steam from reaching a dangerous or explosive point; but my invention, while similar so far as a spring-actuated valve is concerned, diifers entirely in operation and principle from these safety-valves, because my valve is not intended as a safety-valve, but is intended to notify the operator that the vulcanizing-point has been reached and to note the time after that moment and to allow the temperature to gradually increase up to any desired degree. Where the operator has had heretofore to keep a close watch upon the temperature, my invention enables him to dispense with this trouble and to simply note the time from the moment the steam begins to blow off.

By the constant and continuous increase of pressure obtained by the use of a valve constructed to operate as here shown a much finer and tougher quality of vulcanized rubber is produced than if the heat were run at once to 330 and continued there thirty minutes. The escape of steam decreases to a certain degree the rapid increase of heat in the vulcanizer and retards its rising accordingly, and hence the time between the point at which the steam begins to blow ofi and the point at which the vulcanizer is completed is about forty minutes. The flame which heats the Vulcanizer, whether gas or oil, is difficult to so control that the heat shall not rise too high nor sink too low in the operation. My invention saves the operator valuable time in watching the thermometer and all possible liability of spoiling the plates being vulcanized, as the regulating-valve controls the entire operation by gradually and continually reducing the heat and increasing the discharge as the steam increases in pressure. 5 As soon as the forty minutes have elapsed from the time the steam begins to blow oif the operator turns oif the heat and the plate is finished without the slightest liability of being burned or injured in any manner.

Having thus described my invention, I claim- The combination, with a vulcanizer, of a cylinder provided with a valve-seat and a blow-off pipe, the valve, the graduated Valvestem, a spring applied to the valve-stem, and an adjustable cap, by means of which the pressure of the spring is regulated to correspond to the graduations on the stem,- substantially as shown and described.

In testimony whereof I affix my signature in presence of two witnesses.

LEVI STUCK.

Witnesses:

O. A. GURNEY, J. O. RICHMOND.