IMPROVEMENTS IN THE MANUFACTURE OF INDIA-RUBBER AND OTHER BOOTS AND SHOES, AND IN THE PROCESS OF UNITING METAL WITH INDIA-RUBBER TO BE USED IN SUCH Manufacture AND FOR OTHER PURPOSES."
Year: 1881

page_text: LETTERS PATENT to Frederick Richardson, of Providence, Rhode Island,
United States of America, for an Invention of "IMPROVEMENTS IN THE
MANUFACTURE OF INDIA-RUBBER AND OTHER BOOTS AND SHOES, AND IN
THE PROCESS OF UNITING METAL WITH INDIA-RUBBER TO BE USED IN SUCH
Manufacture AND FOR OTHER PURPOSES."
PROVISIONAL SPECIFICATION left by the said Frederick Richardson at tho
Office of the Commissioners of Patents on the 7th December 1881.
FREDERICK RICHARDSON, of Providence, Rhode Island, United States of America,
"IMPROVEMENTS IN THE MANUFACTURE OF INDIA-RUBBER AND OTHER BOOTS AND
SHOES, AND IN THE PROCESS OF UNITING METAL WITH INDIA-RUBBER TO BE
USED IN SUCH MANUFACTURE, AND FOR OTHER PURPOSES."
Invention relates chiefly to improvements in the heels of india-rubber
boot and shoes, consisting essentially in protecting the same by a metal wearing
surface secured to the india-rubber by cementation or otherwise, as hereinafter set
forth, the metal being specially prepared according to my Invention to facilitate
the cementing of the same to the india-rubber. This preparation of the metal for
enabling it to be readily united to india-rubber is applicable for purposes other
than the manufacture of boots and shoes.
The said Invention is partly applicable to boots and shoes, other than such as
are made of india-rubber.
India-rubber boots and shoes, and more particularly india-rubber overshoes, are
subjected to more wear on the heel and more particularly at the rear portion of
the heel than at any other part. As in india-rubber overshoes the heel portion of
the shoe forms a depression into which the heel of the boot or shoe over which it is
to be worn enters, no great increase in thickness at this part is possible; and as
the greatest wear comes on this part of the shoe the rubber is soon worn through,
and water will enter the shoe, destroying its usefulness as a protection in wet
weather.

page_text: The chief object of this Invention is to strengthen and protect this part of the
shoe or the whole heel, and thereby increase the durability of the shoe or boot.
In carrying the said Invention into practice I provide a metallic wearing surface
or guard forming part or the whole of the tread of the heel; holes are made in this
guard through which nails or screws may pass to secure the metal guard to the
heels or the soles, as the case may be; plates or in some cases strips extend from the
outer wearing surface inward between the sole and the heel; these plates are
arranged with openings so that the india-rubber of the sole and the heel may be
united by cementation, secure the metal plate, and with it the heel guard. To
obtain a firm union, sheet india-rubber may be cut of such size and form as will
fill the opening or openings in the plate, or the space between the strips may be so
filled with sheet india-rubber of the thickness of the stripes or plate, and the sole,
heel, and sheets be cemented together. When the whole is subjected to vul-
canization it becomes one mass, and the metal heel-guard is firmly secured within
the vulcanized mass.
I prefer however to secure these metal heel-guards in the following manner :-
I first prefer a roll, press, or stamp, with projections, corresponding with the
shape of the plate or strips forming part of the metal heel-guard to be secured, and
roll, press, or stamp a depression or matrix into either the sole or the heel, or
partly into both, so that when the two are placed together the plate or strips will
fit into the depressions.
To firmly secure the metal heel-guard to the india rubber by cementation I first
placo the metal guards in an acid bath, that is, into diluted sulphuric acid, to
subject the same to the process known as pickling.
From this bath they are washed in water to free them from the acid and are
allowed to dry; the effect of this pickling process is to roughen the surface, remove
all scale or oxides, and cause the coating to firmly adhere to the metal.
I now cover the metal with dissolved india rubber known as rubber cement, and
allow the coat to dry, when another coat of the same cement may be added. The
metal is now ready to be cemented to the india-rubber, or between the. sole and the
heel, by covering the parts in contact with cement, and placing the metal plate
frame or strips in the depressions.
The boot or shoe is now subjected to the process of vulcanization, in which
process as the heat rises, the sulphur contained in the india-rubber melts and is
diffused through the whole mass; when at a still higher temperature it solidifies
and forms the binding material which unites any number of layers of india-rubber
into one homogeneous mass, and consequently firmly secure the imbedded metal
plate, frame, or strip, by which the heel-guard is secured.
This process is applicable to many other uses in which it is desirable to secure
metal to india-rubber or pieces of metal together by means of india-rubber.
In all such cases I clean the surface of the metal with diluted sulphuric acid or
any acid bath that will remove all impurities and secure an intimate union between
the metal and the india-rubber cement.
After covering the metal with one, two, or more coats of india-rubber cement, I
place the india-rubber to be secured to the same under pressure, and subject the
whole to the process of vulcanization, by which the whole becomes one solid mass
and the india-rubber is made to firmly adhere to the metal.
When sheets or other pieces of metal are to be covered with or cemented to india-
rubber to ensure a firin hold and prevent the presence of air between the india-
rubber and metal, which in vulcanizing would ruin the whole by the expansion of
the air by the heat, I place on the previously prepared metal a thin sheet of soft
india-rubber, and roll or press the same firmly on the metal with a heated roll or
plate, so that not only all the air is certain to be expelled, but the sheet becomes
firmly united with the metal and forms a base on which any kind of india-rubber
can be secured by cementation in the usual manner, which cementation is completed
in the vulcanizing oven if a hard surface is required.
India-rubber boots and shoes have but little strength in the heel cap. To give

page_text: them additional strength, I extend the outer rim of the heel or heel-guard upward;
the rim extends above the sole, and not only protects the end of the sole but also
strengthens the heel-cap or counter. The wearing tap may be secured to the shell
by means of a screw, the shell being provided with a raised rim by which the rear
end of the sole is protected. This heel is secured to an india-rubber boot or shoe
partly by cementation and partly by nails. It is also applicable to leather boots
and shoes to which the shell is secured by nails.
The hard cast metal tap furnishes a wearing surface of great durability, and as
the supporting surface is placed on the outer edge of the heel a firmer footing is
insured than is possible with a heel bearing over the whole surface.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Frederick Richardson in the Great Seal Patent Office on the
5th June 1882.
FREDERICK RICHARDSON, of Providence, Rhode Island, United States of America.
"IMPROVEMENTS IN THE MANUFACTURE OF INDIA-RUBBER AND OTHER BOOTS AND
SHOES, AND IN THE PROCESS OF UNITING METAL WITH INDIA-RUBBER TO BE
USED IN SUCH MANUFACTURE, AND FOR OTHER PURPOSES."
This Invention has reference to improvements in the heels of rubber boots and
shoes, and consists in protecting the heels of rubber boots and shoes by a metal
wearing surface secured to the rubber by cementation or otherwise, and further
consists in preparing the metal so that it can be readily cemented to the rubber,
all of which will be more fully set forth hereinafter.
Figure 1 is a perspective view of a rubber shoe, the heel of which is protected
by a metal wearing surface so as to protect the edges of the heel against wear.
Figure 2 shows a plan and section of one of the forms of the metal wearing
surface; Figure 3 is a section of part of a rubber shoe showing the metal heel
guard in solid black. This metal heel guard forms a wearing surface around the
edge of the heel, as shown in Figure 2, and the same is secured partly by
ceinentation and partly by nails, as shown in Figure 3.
Figure 4 shows a plan and section of a metal heel guard provided with an
extended and roughened wearing surface around the edge of the heel. This metal
heel guard is also secured partly by cementation and partly by nails; Figure 5
shews a plan and section of a metal heel guard, the wearing surface of which is
formed of intersecting metal ribs, and the same is secured by cementation, the
openings between the ribs being filled with rubber; Figure 6 is a plan, and
Figure 7, a section of part of a rubber shoe showing a metal plate constructed to
protect the rear portion of the heel and secured partly by cementation and partly
by nails which are clinched over an inner plate, as is clearly shown in Figure 7;
Figure 8 shews a plan and section of a metal heel guard constructed to protect
the rear portion of the heel secured by cementation betwen the rubber sole and the

page_text: rubber heel; Figure 9 represents a plan and section showing a modification of
Figure 8, the inward extensions being so formed that they will firmly hold the
heel guard when cemented between the sole and the heel.
Figure 10 represents a plan and section showing another modification in which
the plate entering between the rubber sole and the heel is provided with pins
constructed to enter both and thus firmly secure the metal heel guard; Figure 11
represents a plan and section showing another modification of the metal heel guard
constructed to protect the rear of the heel and arranged so as to be secured by
cementation between the rubber solo and the heel; the inwardly projecting arms
unite near the centre, and are grooved to increase the adhesion to the rubber;
Figure 12 shows a plan of the rubber heel rolled or stamped with depressions to
receive the metal plate of the heel guard shown in Figure 11. The heel or the sole
may be rolled or stamped so as to receive the plate of the heel guard, or both may
be so rolled or stamped that each will receive one half of the same and the
depressions rolled or stamped into the heel or sole; either or both are made so as
to form a matrix of the plate, so that either of the forms shown in Figures 8 - 9 - 10,
and 11, or any similar forms may be used.
Figure 13 is an enlarged section showing the inwardly extending arms or plate
of the metal heel guard embedded in the heel and secured by cementing the heel and
guard to the sole; Figure 14 is a section showing the metal heel guard embedded in
the sole; and Figure 15 is a section showing the plate of the heel guard embedded
partly in the sole and partly in the heel and secured by cementation; Figure 16
is a plan, and Figure 17, a section of a metal heel consisting of a heel shell arranged
to be secured to the rubber boot or shoe, and provided with a hard metal wearing
surface cast so as to form a bearing around the edge of the heel increasing in width
towards the rear, and to form two such wearing surfaces, so that when one has
been worn smooth the tap may be turned and a new wearing surface presented.
Figure 18 shows a plan and section of a metal heel consisting of a number of
arms, on the ends of which wearing points are formed by extending the metal at
right angles with the arms down to the tread of the heel. These wearing points
may be made so as to form the rear edge of the heol, as is shown in Figures 13, 14,
and 15; or these wearing points may extend through the heel and be surrounded by
rubber so that they form a wearing surface near the edge of the heel; one half of
Figure 18 represents the first and the other half the latter kind, the broken line
indicating the edge of the heel.
Rubber boots and shoes, and more particularly rubber overshoes, are subjected
to more wear on the heel, and more particularly at the rear portion of the heel than
at any other part. As in rubber overshoes the heel portion of the shoe forms a
depression into which the heel of the boot or shoe over which it is to be worn
enters, no great increase in thickness at this part is possible, and as the greatest
wear comes on this part of the shoe the rubber is soon worn through and water
will enter the shoe, destroying its usefulness as a protection in wet weather. The
object of this Invention is to strengthen and protect this part of the shoe or the
whole heel, and thereby increase the durability of the shoe or boot.
Similar letters of reference indicate corresponding parts in all the Figures.
In the Drawings a, a, represent the metallic wearing surface forming part or the
whole of the tread of the heel; b, b, are partial sections of the various heel guards;
c, c, are holes made in the heel guards through which nails or screws may be
entered to secure the metal guards to the heels or the soles, as the case may be;
d, d, are plates, or in some case strips, extending from the outer wearing surface
inward between the sole and the heel, as is shown in Figures 3-11-13-14, and 15.
These plates are arranged with openings so that the rubber of the sole and the heel
may be united by cementation and thus secure the metal plate and with it the
heel guard. To secure a firm union sheet rubber may be cut of such size and form
as will fill the opening or openings in the plate, as shown in Figures 2-3-5-8,
and 11, or the space between the strips, as shown in Figure 9, may be so filled with
sheet rubber of the thickness of the strips or plate, and the sole, heel, and sheets

page_text: cemented together. When the whole is subjected to vulcanization it becomes one
mass, and the metal heel guard is firmly secured within the vulcanized mass. I
prefer however to secure these metal heel guards in the following manner :-I first
prepare a roll, press, or stamp with projections corresponding with the shape of the
plate or strips forming part of the metal heel guard to be secured, and roll, press,
or stamp a depression or matrix into either the sole, the heel, or partly into both,
so that when the two are placed together the plate or strips will fit into the
depressions. Such a matrix is shown in Figure 12. To firmly secure the metal
heel guard to the rubber by cementation I first place the metal guards into an acid
bath, that is, into diluted sulphuric acid to subject the same to the process known in
the art as pickling. From this bath they are washed in water to free them from
the acid and are allowed to dry.
The effect of this pickling process is to roughen the surface, remove all scale or
oxides, and cause the coating to firmly adhere to the metal. I now cover the
metal with dissolved india-rubber, known in the art as rubber cement, and allow
the coat to dry, when another coat of the same cement may be added. The metal
is now ready to be cemented to the rubber or between the sole and the heel by
covering the parts in contact with cement and placing the metal plate, frame or
strips, into the depressions. The boot or shoe is now subjected to the process of
vulcanization, in which process as the heat rises the sulphur contained in the rubber
melts and is diffused through the whole mass, when at a still higher temperature
it solidifies and forms the binding material which unites any number of layers of
rubber into one homogeneous mass, and consequently firmly secures the embedded
metal plate, frame, or strip by which the heel guard is secured.
This process is applicable to many other uses in which it is desirable to secure
metal to rubber, rubber to metal, or pieces of metal together by rubber.
In all such cases I clean the surface of the metal with diluted sulphuric acid or
any acid bath that will remove all impurities and secure an intimate union between
the metal and the rubber cement. After covering the metal with one, two, or
more coats of rubber cement, I place the rubber to be secured on the same under
pressure and subject the whole to the process of vulcanization, by which the
whole becomes one solid mass and the rubber is made to firmly adhere to the
metal.
When sheets of metal or other metal surfaces are to be covered with or cemented
to rubber to ensure a firm hold and prevent the presence of air between the rubber
and metal, which in vulcanizing would ruin the whole by the expansion of the air
by the heat, I place on the previously prepared metal a thin sheet of soft rubber,
and roll or press the same firmly on the metal with a heated roll or plate, so that
not only all the air is certain to be expelled, but the sheet becomes firmly united
with the metal and forms a base on which any kind of rubber can be secured
by cementation in the usual manner, which cementation is completed in the
vulcanizing oven if a hard surface is required.
Rubber boots and shoes have but little strength in the heel cap. To give them
additional strength I extend the outer rim of the heel or heel guard upward. In
Figures 4-5-8, and 17 the rim e extends above the sole and not only protects the
end of the sole but also strengthens the heel cap or counter. In the heel shown
in Figures 16 and 17 the wearing tap A is secured to the shell B by means of the
screw C. The shell B is provided with the raised rim e, by which the rear end of
the sole is protected. This heel is secured to a rubber boot or shoe partly by
cementation and partly by nails. It is also applicable to leather boots and shoes
to which the shell is secured by nails. The hard cast metal tap A furnishes a
wearing surface of great durability, and as the supporting surface is placed on the
outer edge of the heel a firmer footing is ensured than is possible with a heel
bearing over the whole surface.
Having thus described my Invention I claim as new and desire to secure by
Letters Patent,―
First, A rubber boot or shoe, the heel of which is provided with a metal wearing

page_text: surface secured by cementation, substantially as described as a new article of
manufacture.
Second. The combination with a rubber boot or shoe of a heel provided with
a metal wearing surface, secured partly by cementation and partly by nails, as
described.
Third. The improvement in the art of making rubber boots or shoes, the same
consisting in forming depressions on the sole or the heel, or on both, and cemonting
within the same a plate, frame, or strips, forming part of a metal wearing surface
constructed to protect the heel as and for the purpose. set forth.
Fourth. The combination with a boot or shoe of the heel shell B, having the
tap A made of hard cast metal and provided with two marginal wearing surfaces
secured by means of a screw, substantially as described.
Fifth. The improvement in the art of securing metal to rubber or vice versa, the
same consisting in freeing the metal from scale and oxides by an acid bath,
covering the metal with rubber cement, and securing the rubber to the metal by
cementation, as described.
Sixth. The improvement in the art of securing metal to rubber or vice versa,
the same consisting in freeing the metal from scale and oxides by an acid bath,
covering the same with cement, and pressing a thin sheet of soft rubber on the
metal with heat, and then cementing the rubber and metal together before
vulcanization.
In witness whereof, I, the said Frederick Richardson, have hereunto set my
hand and seal, this 19th day of December, in the year of our Lord One
thousand eight hundred and eighty one.
In the presence of
J. A. MILLER, jr.
FREDERICK RICHARDSON. (L.S.)