Improvements in Grinding the Flats of Carding Engines and in Apparatus Employed therefor.
Year: 1888

page_text: Date of Application, 21st Aug., 1888
Complete Specification Left, 18th May, 1889-Accepted, 22nd June, 1889
Improvements in Grinding the Flats of Carding Engines and in
Apparatus Employed therefor.
We. JOHN THOMPSON of the firm of Messieurs Curtis Sons and Company
Engineer, and THOMAS BARKER, Foreman, both of Phoenix Works Manchester in
the County of Lancaster do hereby declare the nature of this invention to be as
follows:-
The object of our invention is to grind the wire on the flats used in revolving flat
carding engines so that the points of the wire on each flat when in working position
shall be parallel to or equidistant from the wire on the cylinder throughout the whole
length of the said flat.
"
It is found that as each flat is supported upon the guiding frame or bend at its
extreme ends the weight of the flat itself tends to cause a deflection therein which
brings the central points of the wire on the said flat nearer to the cylinder than those
at the ends thereof. The chains also which act inside the supports of the flat tend to
increase the deflection which although slight causes unequal carding of the fibre under
treatment.
To overcome this defect we grind the wires on the flats in a gradual curve so that
the deflection of the body of the flat brings all the points parallel to those on the
cylinder.
For this purpose we make use of an emery roller with a slightly barrelled surface
that is to say larger in diameter at the centre than at the ends.
If preferred an emery disc or a narrow drum may be used instead of this barrelled
roller but in this case the disc or drum must be guided as it travels along the
surface of the flat by a rod bar or other fixture curved to produce the desired surface
of the said flat.
Dated this 20th day of Aranet 1888
CHARLES A. DAVIES,
4, St. Ann's Square, Manchester, Agent for the Applicants.
COMPLETE SPECIFICATION.
Improvements in Grinding the "Flats" of Carding Engines and in
Apparatus Employed therefor.
We JOHN THOMPSON of the firm of Messieurs Curtis Sons and Company
Engineers and THOMAS BARKER, foreman both of Phoenix Works Manchester in
the County of Lancaster do hereby declare the nature of this invention and in what
manner the same is to be performed, to he particularly described and ascertained in
and by the following statement :—
The object of our invention is to grind the wire of the "flats" used in "revolving-
flat" carding engines, so that the points of the wires on each "flat" when in working
position shall be parallel to or equidistant from the wire of the cylinder throughout
the whole length of the said flat.
It is found that as each flat is supported upon the guiding frame or "bend" only
at its extreme ends, the weight of the flat itself tends to cause a deflection downwards
in the centre thereof, which brings the central points of the wire on the said flats
nearer to the surface of the cylinder than those at or towards the ends thereof.
The chains also which act inside the supports of the flat tend to increase this
deflection which although but slight causes unequal carding of the fibre under
treatment.

page_text: Our invention is designed to remedy this defect and the means which we propose to
employ for that purpose will be readily understood on reference to the sheet of
drawings hereunto annexed and the following explanation thereof.
Fig. 1. represents in elevation a "flat" being ground upon our improved principle,
a being the "flat" and the grinding roller, and we would here observe that for the
sake of more clearly showing the principle of our invention we have somewhat
exaggerated the deflection of the flat caused by its own weight when supported by its
two ends, and also the curve given to the grinding roller.
It will be evident that when grinding a flat in the position shown at Fig. 1. (that is
face upwards and with a downward deflection in the centre) if a cylindrical grinding
drum be employed, as usual, the tendency would be to grind away both ends more
than the centre, and that when the flat was placed in working position, (that is face
downwards as shown at Fig. 2 and with the deflection reversed) the wires at the
central part would be nearer to the wires of the card cylinder c than the outer parts
or ends which had been more ground away as above described.
To overcome this defect we grind the wires of the flats in a gradual curve parallel
with the curve of the deflection (as shown at Fig. 1.) so that the reverse deflection of
the body of the flat when turned over face downwards, or in its working position as
shown at Fig. 2 will bring the points of the wires on the flat exactly parallel to those
on the main cylinder.
For this purpose we make use of an emery grinding roller 6 with a slightly barrelled
surface, that is to say larger in diameter at the centre than towards the ends as shown
(exaggerated) at Fig. 1.
If preferred an emery disc or a narrow drum d (Fig. 3.) may be used instead of
this barrel shaped roller, but in this case the disc or drum d must be guided as it
travels along the surface of the flat a by a rod bar, or other fixture e curved to produce
the desired surface of the flat.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed we declare that what we
claim is :-
First. Grinding the wire of the flats when laid face upwards to a slight curve
corresponding to that caused by their deflection, so that when turned over face
downwards (or in working position) the reversed deflection shall bring their surface
into a straight line exactly parallel with the surface of the main carding cylinder.
Secondly. We claim for the above purpose the construction and use of a grinding
cylinder of a barrelled form or of a narrow grinding wheel or disc in combination
with a fixed curved guiding surface, all substantially as and for the purposes herein-
before set forth.
Dated this 17th day of May 1889
CHARLES A. DAVIES,
4, St. Ann's Square, Manchester, Agent for the Applicants.