US2648108A - Sterilizer - Google Patents

Description

J. B. PENTZ Aug. 11, 1953 STERILIZER Filed June 28, 1948 WATER LEVEL INVENTOR Mm @/Lm;

ATTORNEY Patented Aug. 11, 1953 UNITED vSTATES* PATENT OFFICE James B. Pentz, Staten Island, N. Y. Application .time .28, 194s, serial No. 35,553

1 The invention is concerned with methods of sterilization by means of superheated steam and with apparatus connected therewith. More especially, it is concerned with the cover of such apparatus. The cover may be employed in combination with steam chests such as the ordinary type of sterilizer or the autoclave sterilizer where steam is held under pressure. It is also adapted to various types of cookers. y

The main object of the invention is to reduce if not to eliminate the condensation of steam in a conventional steam chest when provided with a removable cover. As the cover 4extends over an air space which acts as an insulator between it and the portion usually referred to as the boiler, and as the cover is often open, condensation of the steam coming in contact with the cooler surface of the cover is unavoidable, resulting in defective lasepsis because of the drippings from the cover.r I have found that it isthis failure of the heat in the cover to at least equal the heat ofthe walls ofthe steam chest which is responsible for this vdefective asepsis.) kI have also found that the defects are Aimmediately 'corrected by jacking up the heat in thecover'by means independent of the conventional boiling process. This novel attack of the problem not only allows surgical instruments placed in the steam chest to become thoroughly sterilized,

but eliminates permeation of moisture and dripwe n ping of water into such articles as-surgical dressings placed in the steam chest. What'v is no'less important is that these results are lobtained'fin so short a space of time that it Well may besaid that they are instantaneous.

In accordance with the above stated object, I provide the cover of my steam chest with a hot plate, usually by means of an electric current passing through a resistance wire in the well known manner. The hot plate may be either on the inside or on the outside of the cover, but always in close contact therewith.

While my invention is herein illustrated mainly in its application to present day sterilizers, it will be understood that the novel features embodied in the cover will be equally eflicient when the invention is applied to steam chests of other description, as, for instance, pressure cookers. It will be understood, further, that the steam chest may be of any suitable configuration, although here shown as cylindrical in form.

In present day practice, after the process of sterilization has been completed and the sterilized articles are about to be removed from the steam chest, the operator, upon removing the cover, finds the inside of the cover thoroughly 1 Claim. (o1. 21-95) v 2 saturated with condensed steam which apt to drip back into the sterilizer or fall to the floor of the room. f

It also has been found that the surgical dressings, which usually are placed in a tray near the top of the sterilizer adjacent the inside of the cover, become contaminated by the condensations dripping from the cover, especially while the cover is being removed.

The present invention obviates all of the above difficulties by providing an electrical heating unit in close contact with the cover which keeps the entire lsterilizer' equally heated and does away with any cool portion Where the steam may condense and drip back into the surgical,dressings.l Furthermore, in my process no air pockets are formed adjacent the cool cover which tend to delay orA frustrate sterilization. It has been mentioned before that the heating unit may be underneath the cover or over it, but in all cases it must be in close contact with the cover. Other objects and advantages of the invention, not specifically mentioned above, will become apparent from the specification which follows and from the accompanying drawing, in vwhich Figure 1 is a vertical cross section of a sterilizer embodying the present invention, with the usual, standard valves and additional features and xturesomitted for thesake of clarity.

' Figure 2 is a modied form of the invention, also shown in vertical cross section.

Figure 3 is a similar cross section of aV type of the invention provided with the preferred form Qfcover U y L Figurelv is 'a top plan view of the electrical element used for heating the various covers.

Figure 5 shows the present invention adapted to a deep Well pressure cooker.

Referring to the drawing in detail, in Figure 1 there is shown in a diagrammatic Way a conventional sterilizer comprising a chest I0 having a base portion II and a cover I2, with the usual heating element I3 in a chamber I4 at the base II of the chest I0. The chest I 0 is provided with brackets I5 and I6 secured therein for supporting a pair of removable trays I'I and I8. These trays have openings I9 for the reception of hooks for placing them into and removing them out of the chest I0. The trays I'I are used for holding surgical instruments, and the trays I8 are for bandages and other surgical dressings to be sterilized. The cover I2, which may be hinged or bolted to the chest I0, contains a heating unit I3 in a chamber 2|, formed by the shield I2'. The shield l2' may be provided With perforations along its upper surface to allow heat to escape, or it may be omitted altogether. The shield I2 is removably secured to the cover I2 in any suitable manner by means omitted from the drawing. When the steam strikes the inner surface 40 of the cover I2, the cover is heated by the heating element I3', which prevents the condensation of steam on the surface 40, so that no water may drip onto the bandage tray I8 during sterilization and no Water will drip to the iioor when the cover I2 is removed from the chest I after sterilization.

The heating elements I3 and I3' are preferably circular in plan and cross section and are sheathed or covered with an insulating material 22. The terminals of the heating elements are adapted to be connected to a plug 23 which, in turn, is connected to the house current. When the shield I2 is omitted, the heating unit is exposed. It may be of any suitable form. In some cases, it may be provided by a flat iron.

The apparatus may be used both for sterilization with steam, in which case the water in the steam chest is heated by the electric element I3, or for dry heat sterilization, in which case the chest is emptied of the Water, as by means of a petcock 4I shown in Figure 1. When sterilizing by steam, the level of the water is usually maintained above the tray I1 which holds the surgical instruments. When sterilization is done by dry heat, the surgical dressings are placed in the upper tray I8, the heat again being applied through the electrical element I3, but an absorbing pad 42, preferably of asbestos, is placed over the element I3. To prevent the burning out of the heat element, the absorbing pad 42 is kept moist by allowing water to drip onto it from the cup 24.

In the modified form of sterilizer shown in Figure 2, the tray I8 containing the surgical dressings may be dry heat sterilized in a separate container 25 having an exposed heating unit 26 connected to a plug 2l. In this modification, it is immaterial whether the steam chest is emptied of water or not, in so far as sterilization of surgical dressings is concerned.

The container 25 is flared at the base to snugly fit over the shield I2' and may be removed by the bail 28. In this type of the invention, the circular brackets 23 may be interrupted so that the interrupted flange in the tray I8 may be inserted from the bottom of the container 25 and rotated for locking and removing.

Figure shows a type adapted to a pressure cooker 30 which may or may not be of the deep Well character. The cooker is shown seated in 4 an electric range 3| which has an independent electrical heating unit 32.

In the type illustrated in Figure 3, the cover comprises a dome 32 and a flange 33 which may or may not be bolted to the steam chest I0. It consists of metal plates 34 and 35 which are sealed together at the flanged portion 33 but separated at the dome portion to form a chamber 38 for accommodating a heating unit I3. To prevent air pockets which often are formed during sterilization at or near the cover of the steam chest, the steam which enters the chamber 36 through the upper port 31 causes the heavier air to be driven out through the lower port 38, these ports being provided in the absorbing lining 39 and the metal plate 35.

Many variations in the structure of the device and in the character and disposition of its elements may be made by those skilled in the art Without departing from the substance and spirit of the invention, the scope of which is cOvered by the claim which follows.

I claim:

In a steam chest for sterilizing surgical instruments and dressings, a removable top cover for said chest, spaced trays for respectively holding said instruments and dressings, said tray for said dressings being disposed above said other tray and adjacent said cover, and means in contact with said cover for heating said dressings independently of the steam in said chest.

JAMES B. PENTZ.

References Cited n the file of this patent UNITED STATES PATENTS Number Name Date 553,561 Lundholm Jan. 28, 1896 802,601 Scanlan Oct. 24, 1905 1,122,271 Golden Dec. 29, 1914 1,744,854 Zinna Jan. 28, 1930 1,830,287 Ohlin Nov. 3, 1931 1,969,614 Klopfenstein Aug. 7, 1934 1,975,082 Bucy Oct. 2, 1934 2,047,973 Lawton et al. July 21, 1936 2,085,573 Buttolph June 29, 1937 2,240,001 Harvey Apr. 29, 1941 2,362,117 David Nov. 7, 1944 2,415,238 Emerson Feb. 4, 1947 OTHER REFERENCES The Principles and Practice of Textile Printing, by Knecht and Fothergill, third edition, Charles Griffen and Company, Ltd., London, 1936, see page 184.

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