Improvements in Valves for Air Compressors and the like.
Year: 1897

page_text: Date of Application; 27th Feb., 1897
Complete Specification Left, 24th Nov., 1897-Accepted, 8th Jan.,
1898
PROVISIONAL SPECIFICATION.
Improvements in Valves for Air Compressors and the like.
I, JAMES MCCULLOCH, of Portreath, in the County of Cornwall, Engineer, do hereby
declare the nature of this invention to be as follows:-
This invention relates to inlet and outlet valves of the gridiron type for use in air
compressors and like apparatus, said valves having bevelled faces and guides at the
back and face whereby they are caused to act more efficiently and wear longer with-
out repair than valves of the kind as hitherto constructed.
In one form of valve, constructed according to this invention, a bevelled face is
formed at the outer edge of the circular flat face of the valve proper, and a corres-
ponding bevel is formed in the flat face of the seat. The valve is also provided with
pins or projections extending centrally from its back and face, the pin at the back
working in a recess in the cover or other suitable part of the valve casing, and the
pin at the face working in a hole in the valve seat. By these means the valve is
accurately guided in its travel to and from the valve seat and uneven wear of the
face is prevented, thus avoiding the loss of air or the like by leakage.
In another form of this valve a central recess is provided in the valve and into the
said recess, a pin or stud attached to the cover or other part of the valve case,
projects so as to guide the valve in its travel.
Deted this 27th day of February 1897
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.
I, JAMES MCCULLOCH, of Portreath, in the County of Cornwall, Engineer,
do hereby declare the nature of this invention and in what manner the
same is to be performed, to be particularly described and ascertained in and by the
following statement :—
This invention relates to inlet and outlet valves of the gridiron type for use in air
compressors and like apparatus, and is designed to provide a construction of valve
which shall be capable of acting more efficiently and lasting longer without repair
then are valves of this kind as ordinarily constructed.
According to the said invention I provide improved means for accurately guiding
the valve in its travel or lift thus avoiding uneven wear of the valve face such as
would lead to loss of air or the like by leakage. To this end I provide a central pin

page_text: or projection on the valve face, and a central recess or socket at the back of the
valve, the pin passing through a central aperture in the valve seat and the recess
or socket receiving a pin or stud attached to the valve cover or other part of the valve
case.
In order that the invention may be clearly understood and readily carried into
effect, I will proceed to describe the same by aid of the accompanying drawings, in
which:
Figure 1 is a plan, and
Figure 2 a section on the line xx, Figure 1, shewing an arrangement of valve
according to my invention, the valve casing being omitted.
Figure 3 shews in plan half of the valve and half of the valve seat..
a is the valve proper, a¹ being the central pin and a² the rceess or socket above
referred to. b is the valve cover which is recessed as at 6 and has a pin or
projection 62 fitting in the socket a².
1
c is the valve seat which has a central aperture c¹ in which the pin a¹ of the 1
valve works.
It will thus be seen that the pin a' and socket a² form guides for the valve and
ensure the latter remaining always parallel with the seat as it opens and closes.
The valve seat c has the upper edge thereof bevelled or inclined as at c², the
bevelled portion extending to the edge of the valve, and the valve a being
correspondingly bevelled.
The valve a is also provided with segmental apertures a³ arranged opposite
corresponding solid portions c³ of the valve seat.
It will be obvious that I may vary the arrangement of the pins a' and 62 without
departing from the nature of my said invention. For instance both pins may be
arranged on the valve and the socket a² may be formed in the valve cover if
desired.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what I
claim is
1. A valve for an air compressor or the like provided with means substantially as
described for guiding the valve in its travel or lift.
2. An air compressor valve constructed and operating substantially as herein before
described with reference to the accompanying drawings.
Dated this 23rd day of November 1897.
HASELTINE, LAKE & Co.
45 Southampton Buildings, London, W.C., Agents for the Applicant.