US790562A - Manhole-cover. - Google Patents

Description

' No. 790,562. PATENTED MAY 23, 1905.

J.IFA.DOIRSEY. I MANHOLE COVER.

APP LIOATION FILED FEB. 17.1906.

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UNITED STATES Patented. May 23, 1905.

JOHN F. DORSEY, OF PORTSMOUTH, VIRGINIA.

MANHOLE-COVER.

SPECIFICATION forming part of Letters Patent No. 790,562, dated May 23, 1905.

Application filed February 17, mos. Serial No. 246,061.

.To all whom it may concern:

Be it known that I, JOHN F. DORSEY, a citizen of the United States, residing at Portsmouth, in the county of Norfolk and State of Virginia, have invented certain new and useful Improvements in Manhole- Covers and Joints, of which the following is a specification.

My'invention relates to manhole plates or covers and joints therefor.

The object of my invention is to provide manhole and hand-hole plates for steam-boilers and the like that are incapable of having their packing blown out by pressure, which often happens with disastrous results.

By my invention I am also enabled to make a joint and renew the packing thereof when the boiler or tank is full of water, which cannot be accomplished with the devices now in use.

The invention will be more fully understood from the accompanying drawings, forming a part of this specification, in which Figure 1 is a sectional elevation through the parts pertinent to my invention. Fig. 2 is an elevation of the same with several members drawn apart. Fig. 3 is a plan of the plate and its packing. Fig. I is a plan of the compression plate or disk. Fig. 5 is an enlarged part-sectional elevation showing the details of the joint.

In the drawings, in which like referencenumerals indicate similar parts in all the views, 1 is the boiler or tank shell, through which an opening is made for the manhole or hand-hole in the ordinary manner.

2 is the plate, having a raised part 3, forming the flange 4;. The plate has a bolt 5 screwed into it and having threads the entire length thereof and extends from the plate a suitable distance, as shown.

6 is a clamping disk or plate having a flange or rim 7 around it at right angles to the plane of the web or disk portion 6, and therefore forms a dished or flanged depressed surface.

7, Fig. 4:, is an aperture for the passage of the bolt 5 and will be further described hereinafter.

8 is a gasket of some compressible packing portion 3 of the plate 2. The united parts as above described are then inserted into the boiler through the opening provided for the purpose and the guard applied and secured to the boiler by its nut.

9 is the clamping-nut for the packing and is located between the plate 6 and the guard or dog 10 and is screwed up after the nut 11 is tightened.

Referring to Fig. 5, when the plate 6 is compressed by the nut 9 the packing 8 is distorted and fills the very small clearance-space 12 between the portion 2 and. the packing, preventing an escape of steam between the shell 1 and the flange 7 of the disk or plate 6.

As shown, my invention provides for a joint made upon the manhole .or hand-hole plate, the packing not being located upon the inner surface ,of the boiler or tank shell. Therefore the packing cannot be blown out and remains tight for all pressures, the maximum of which may be very high without affecting the efficiency of thejoint.

t is usual to place the packing upon the flange of the plate and insert it into the boiler, the packing being next to the inside surface of the boiler-shell, so that they often blow out and leak. In my present invention I have provided means to make a safe and steamtight joint which is both cheap and eflicient and is confined to the edge of the manhole or hand-hole opening and not within the boiler.

I am not confined to the precise details shown in the drawings, as I may make such changes as may be deemed expedient without departing from the subject-matter claimed or sacrificing any of the advantages thereof.

Having described my invention, what I claim, and desire to secure by Letters Patent, is

1. An elliptical manhole-plate comprising a flanged independent member and a dished member, a ring of rectangular or square packing upon the flanged member and compressed by the edges of the dished member, and means carried by both plates to expand the packing in one direction against the edges of the manhole.

2. An irregular manhole plate or cover comprising a flanged member and an interlocking member adapted to slip over the flanged memher, a ring of square or rectangular packing between the said members, a bolt secured to one member and movably passing through the other, and means actuated by the said bolt to expand the packing against the edges of the manhole by the interlocking member in one direction.

3. A manhole 0r hand-hole plate having the flanged plate 2, the interlocking member 6, the flange 7, the square or rectangular packing 8, the clamping-bolt 5 and the guard or dog 10 substantially as shown and described.

In testimony whereof I have hereunto a1- fixed my signature, in the presence of two witnesses, this 14th day of February, 1905.

JOHN F. DORSEY.

Witnesses:

WALTER B. BURROW, THOMAS M. BOYLE.

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