Year: 1886

page_text: We SAMUEL ERASTUS MOWER and THADDEUS FOWLER, both of Milford, Con-
necticut, United States do hereby declare the nature of our invention and in what
manner the same is to be performed, to be particularly described and ascertained
in and by the following statement :—
t
This invention has for its object to construct an apparatus by which to rapidly
and economically produce saws from strips or bands of metal and to temper the
saws so made at or near their teeth, leaving the backs of the saws softer than their.
toothed edges.
In the invention herein described, a strip or band of steel, fed into that part of
the apparatus by which the saw is made, is intermittingly acted upon first at one
and then at the other side of the said strip or band by a tooth cutting tool, while
the latter is supported at each side by a die, the teeth being cut and set singly one
after the other.
The dies between which the strip or band is fed longitudinally have recesses
corresponding in shape and size with that of the pieces to be cut from the strip in
order to leave teeth, a part of each of the said dies at one side the notch therein
being beveled or inclined in order to permit the tooth being formed to be bent to
one side or set, the completion of the cutting of each tooth also serving to set it.
The different parts of the tooth forming apparatus referred to are made adjustable
to enable strips or bands of different width and thickness to be operated upon, and
by changing the tooth cutting tool and dies and the length of the feed stroke, the
size of the teeth may be varied.
The strip or band having teeth cut at one edge thereof, as it is delivered from
the saw making part of the apparatus, is at once preferably first heated below the
temper point, and then the toothed edge of the saw so heated is subjected to a
tempering heat and immediatly cooled or tempered, thus hardening the teeth in
excess of the central part and back of the saw, the tempered saw being then
preferably wound upon a reel ready to be subsequently cut into suitable lengths
for use.
The invention herein contained consists in dies to support at both sides the
metal strip or band to be cut at one edge to form a saw, and a tooth cutting tool

page_text: see Fig. 3, in the plate A°, enters the cam groove in the cam disk C, the rotation
of the said cam disk effecting the reciprocation of the carriage and the movement
of the tooth cutting tool backward and forward along the grooves m m of the dies,
the said tool passing from the groove of one into the groove of the other side die
and at such time cutting from the strip or band D between the dies a piece of
metal to leave a tooth of the desired depth or shape, the tooth cutting tool at
alternate strokes cutting through the band or strip from opposite directions, the
band or strip being fed longitudinally during the interval between each stroke of
the tool, the tooth cutting tool cutting out a piece of metal at each successive
stroke to the right and then to the left.
The feeding mechanism for the strip or band D is shown as composed of a slide
block E, provided with a stud 13, and having at its opposite sides walls 34 and 35,
the former wall having an attached toothed wedge 12.
The stud 13 is surrounded by a toothed ring 14, a spring 15 between the stud
and the inner side of the ring normally acting to keep the ring pressed into the
narrowing space between the wedge and strip D, as in Fig. 2, the periphery of
the ring engaging the strip at the point 25 and moving the said strip with the
slide block when the latter is moved in the direction of the arrow thereon, see
Fig. 2, by the arm 1 of the lever E pivoted at e' the other arm 2 being slotted at 3
and joined by a pin 4 to a link 35 pivoted to the lower end of the slide rod F,
provided at its upper end with a head 5, carrying a roller which is acted upon
by the cam B when it is desired to cause the slide block and the devices described
to feed the band or strip forward, the length of the forward or effective stroke
being regulated or determined by the screw N, the inner end of which stops the
slide block E sooner or later in its outward movement.
In Fig. 1 the adjustement of the screw N is such as to regulate a short stroke
for the feed, the roll r not rising to its full extent as the cam retires, the spring S
on the rod F remaining somewhat compressed.
As the slide block E is moved backward the backward movement of the strip
or band with it is prevented by a ring 16 on a fixed stud 13, cooperating with a
fixed but toothed incline 17, the ring 14 during the backward movement of the
slide block E and while the strip or band D is held by the ring 16, being forced
toward the point of the incline by its contact with the strip.
For the production of saws having their teeth of uniform depth it is necessary
that the upper straight edge of the strip or band being fed past the dies and punch
should be kept against a gauge P, and herein the said gauge is held down by
screws 38.
i
The lower edge of the strip D is acted upon by a plunger b surrounded by a
spring & both placed in a sleeve b³ a nut 21 being on the reduced part K of the
plunger to control the movement of the same.
In operation, let it be assumed that the band or strip is placed between the
faces of the two dies each die touching one side of the said band or strip. The
intermitting feed of the band or strip is in the direction of the arrow Fig. 2.
The tooth cutting tool at each stroke to the right and to the left cuts from the
band or strip a piece of metal to leave a space o, which outlines the inclined back.
of one tooth and the vertical face of the tooth next ahead of it, the back of the
latter tooth having been formed by the tooth cutting tool and die at the preceding
stroke of the tool in the opposite direction, and as the tool acts to cut into the
metal and remove a portion thereof as shown at o³ by dotted lines Fig. 8, the said
tool first pushes the part of the metal at o² aside and against the inclined face a³
of the die, and then the metal becoming firmly seated on the die, the tool cuts
through the metal leaving the part o², constituting the point of the tooth turned
aside or set, as it is called and as shown in Fig. 8.
The toothed metal strip or band with its teeth cut and set passes from that
part of the apparatus above described to the tempering apparatus, to be hereinafter

page_text: described, and which is supported upon a framework A', 'Aº, of suitable shape to
sustain the different parts of the said tempering apparatus.
The toothed metal strip or band is fed forward through slots 60 in the sides of
a jacket 61, within which is located burners 62 62 screwed upon nipples of a
base 63 attached to the bed plate A7, the base 63 being connected by a pipe 64,
and projection 65, with a gas supplying reservoir 66, the, said burners forming
a preliminary heater and by which that portion of the toothed metal strip or band
above the burners 62 62 is moderately heated.
groove of a
screws 68.
From the preliminary heater the toothed metal strip or band passes through a
guide carried by an upright 67 attached to the bed-plate A7 by
The depth of the groove in the guide 2³ is such as to enable one edge only of
the toothed metal strip or band to project above the guide, the said edge so
projecting receiving against its opposite sides the flame from blow pipes 69, con-
nected by rubber pipes 70 with pipes 71, of a reservoir 72 containing compressed
air, the said blow pipes also having connected to them pipes 73 fitted to the short
pipe 74 inserted in the gas reservoir 66, the blow pipes being thus supplied with
gas and air in usual manner.
.
The projecting edge of the toothed strip or band is raised to a temper heat by
the blow pipe flame, directed against it from opposite sides, and immediately
thereafter receive upon it water or other tempering fluid from a small discharge
tube 75 of a cock 76, supplied with water by the pipe 77 in communication with
a water supply pipe preferably under a head or pressure.
The water discharged upon the heated metal band effects the hardening of
that edge which was brought to tempering heat by the blow pipes leaving
the main part or body thereof and its opposite or untoothed edge, soft or
unhardened.
The saw tempered as described at its toothed edge, is wound upon a reel 79
supported upon a post 80, fitted, loosely in a foot 81 and rotated by a sheave S2,
connected by a belt 83 with a second sheave 84 rotating on an arm 85 secured to
the column A, the, sheave 84 being connected and revolved by a belt SG passing
over a sheave 87 on the main shaft a, and rotating with the said shaft, the metal
strip or band being fed to the saw making machine from a reel 88 loose on the
post 89 of a foot 90.
If desired the preliminary heater may be dispensed with and the edge of the
metal strip or band be subjected to the action of the blow pipes without first
moderately heated, but in practice it is prefered to employ the construction
shown in the drawing, and if desired it will be understood that the band might be
raised to tempering heat by a single blow pipe.
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed we declare that what
we claim is:
1. The dies to support at both sides the metal strip or band to be cut at one
edge to form a saw, and the tooth cutting tool to cut into the said band from
one and then from the other side, combined with suitable mechanism to feed the
said band intermittingly between the said dies, substantially as described.
2. The dies d³ beveled or inclined at a combined with the tooth cutting too!
to notch or cut the band to form teeth set and set the same as the-are-cut;
substantially as described.
3. The tooth cutting mechanism containing dies a tooth cutter, and feeding
devices to move the metal strip or band, combined with an apparatus to the
heat the said strip or band at its toothed edge and to temper the saw, leaving
the toothed edge harder than the body and back of the band, substantially as
described.
:

page_text: 4. The herein described improvement in the art or method of manufacturing
saws from bands or strips of metal which consists in feeding the strip or band
into a tooth cutting machine, cutting teeth at one edge thereof, and passing the
toothed strip through a tempering apparatus adapted to temper and harden
the toothed edge leaving the body and back of the saw comparatively soft or
untempered, substantially as described.