Year: 1892

page_text: Figures 5 to 8 are detail views of various parts of the setting device.
Figure 9 shows the support used in setting circular saws, and
Figure 10 is a cross section of the saw-blade guide.
The combined mechanism is arranged upon a table A resting upon a suitable
pillar or support and receives motion from the main shaft a. By means of the
bevelled friction-wheels a' a motion is conveyed to it through the medium of a
strap upon a strap-pulley B. Upon the shaft of this pulley B is mounted
a toothed wheel e gearing with the wheel rigidly secured upon the shaft cl.
The wheel follows the movements of the shaft and in addition to this is
capable of moving to a slight extent along the said shaft upon the feather d'. By
means of a set-screw the wheel d is retained in the adjusted position.
throwing this wheel d into or out of gear, as the case may be, the setting
mechanism, hereinafter to be described, is set in motion or arrested.
By
The saw-blade is guided, and the emery wheel oscillated, from the shaft c'.
Upon this shaft c' also an eccentric (Figure 1) is keyed, upon the periphery
of which rests the slide C working in the guide e in the supporting table A. Into
this slide C is screwed the spindle e¹, in the head e² of which the roller f is
loosely journalled, so that this roller does not necessarily follow the movements of
the spindle e. Upon the said roller flies the bent frame or yoke D carrying the
emery-wheel and adapted freely to turn about the bolt or rod of the adjustable,
pivotted bracket E (Figures 1 and 4). The emery or grinding-wheel F is mounted
in the frame D in such a manner that its axis in each position exactly coincides
with the vertical plane of the saw-blade, whereby an uneven sharpening of the
teeth is effectively prevented. As the arm of the yoke D enters a groove provided
for the purpose in the roller f the rising and sinking movements of the slide C are
transmitted to the emery-wheel. The pivotted block E is adjustable along a
grooved or slotted supporting segment G, and by tightening the screw 9, the head
of which moves in the groove g₁ of G, it may be retained in any desired position.
The support G is secured to the table by screws or the like.
The conical trunnions or bearings of the emery or like grinding-wheel F are

page_text: supported at /¹ thereby rendering the said grinding wheel adjustable sideways,
bolts or screws i serving to retain it in the adjusted position. To secure a strong
and reliable support for the grinding-wheel F, the conical trunnions & are truncated, so
that the wear of these trunnions both at the end surface and on the circumference
is always uniform. The size and shape of the grinding-wheel may vary according
to the desired shape of the teeth. As the grinding wheel in addition to its
rotation on its own axis, is adapted to oscillate on the bolt or spindle f; the back
of each tooth is so sharpened as to assume a somewhat concave shape and the
grinding is directed towards the point of the tooth, which is one of the require-
ments for a good saw-cut.
Lines I and II show the two extreme positions which the shifting yoke is
capable of reaching upon the supporting segment G. The grinding-wheel is
driven from the pulley 1 by means of a band cord or equivalent and through the
medium of two guide-pulleys 2 and 3, whence the band or cord returns to the
pulley 1. The socket 4 of the guide roller-support 5 is supported by a disc 6 and
may be retained in any required position thereon by means of the bolt or screw 7.
The feeding or guiding mechanism is also operated from the shaft c¹, provided for
this purpose with a tappet or cam k, which at each revolution once depresses the
horizontal arm of the bell-crank lever pivotted at 1. The vertical arm of the
bell-crank lever carrying the blade or arm m, adjustable in the guide / and
exchangeable, then performs a movement in the forward direction and causes the
saw-blade to advance the space of one tooth, whereupon the spring m¹ pulls the
bell-crank lever back to its initial position, in which its vertical arm rests against
the set-screw n. According as this screw n to a greater or less extent is screwed
into the support n', the displacement of the vertical arm of the bell-crank lever
will be confined within narrower or wider limits, and the adjustability of the
feeding device will vary accordingly. The feeding takes place for each successive
tooth separately, in such a manner that after one tooth is sharpened the next tooth
is fed forward and for this purpose the curve of the tappet is such, that the return
of the feeding blade, though very rapid, causes no violent shock of the bell-crank
lever against the screw n.
To secure all the parts of the guiding or feeding mechanism in the proper
positions, previously to setting the machine in operation, the shaft c¹ is acted upon,
being for this purpose adapted for operation by hand; for example, if no circular
saw is to be sharpened or set, a crank-handle o may simply be fitted to c'.
the front end of is made inaccessible by a circular saw-blade, the shaft c¹ may be
driven by means of a hand-wheel o'.
Where
His a device for guiding band and veneer-saw-blades. By turning the hand-
wheel p the bevel pinion J and through it the vertical screw-spindle j are set in
motion, whereby the blade-guide is caused to rise or fall along with the saw-blade
which it guides at the centre and at both ends. y g' are the central and lateral
guides for the vice or screw-holder and the brakes for the saw-blades. These
guides are constructed as follows:-The removable front part r of the guide shown
in Figures 1 to 10 is connected with the portion secured to the supporting table by
means of a screw r'. The saw-blade passes between the two parts and is retained
in position by the slightly yielding action of the front portion which at the same
time acts upon it as a check or brake. By means of the set-screw the result is
secured, that the plates is always in contact with the surface of the saw-blade,
which is desirable both for correctly guiding and properly checking the saw.
When a saw-blade is inserted or removed all the front parts of the guides are
turned up about the screws whereby free access is obtained on the front side.
The saw-blade is secured in the well-known manner to a support L which may also
be raised and lowered by means of the vertical screw-spindle j.
In operating the saw-setting mechanism the wheel d is thrown into gear with
the wheel mounted upon the shaft s'. The front end of this shaft & carries a¦
disc or cam O adapted to actuate the setting mechanism proper. This mechanism
consists of two checks tt', one of which t is movable, and the other t¹ stationary.

page_text: The movable cheek is supported by the piece to fitted within a dove-tailed
groove u. t designates two rails by leaning against which the rails & t¹ retain the
proper position. The cheeks t t¹ are adjustable according to the pitch of the saws,
screws being provided for fixing them in the adjusted position. The spring u', one
end of which is secured to the supporting table A, while the other end is attached
to the sliding piece to of the cheek t, constantly presses the slide to into contact
with the disc and causes it to shift inwardly and outwardly to suit the projections
and recesses of the saw. When the cheek t is thus moved inwardly the inclined
setting tooth presses the tooth of the saw passing between the two cheeks & and t¹
against a correspondingly inclined surface provided on the stationary cheek t',
Figures 5 to 8. A similar movement in the opposite direction is performed by the
setting tooth of the stationary cheek t¹, so that two teeth are set simultaneously.
The movable cheek t then recedes and the steering or feeding mechanism above
described causes another pair of saw-teeth to advance for setting. The saw-blade
is constantly kept in contact with the movable cheek by spring-action applied in
any suitable manner. The stationary setting cheek with its support may be removed
when the setting device is not required, so that free access to the front part of the
table is afforded to the saw-blades. N Figure 9 is an auxiliary support intended
to replace the guide H when a circular saw is to be set, which saw the said support
receives at y. The circular saw is moreover held between two leather discs, which
by their friction exercise a convenient checking action upon it. The sharpening
and setting may not take place simultaneously. When the piece H is raised by
means of the hand-wheel p both the saw-blade and the grinding-wheel may
during the operation be brought into any desired position by suitably screwing
up the arm m in the guide and correspondingly screwing inwards or outwards the
screw-spindle.
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. In a machine such as described a support such as G with the grinding-wheel
supporting yoke so arranged that the grinding-wheel may be set to the required
angle, while being in all positions capable of oscillating in the plane of the saw-
blade substantially as described and illustrated in the accompanying drawings.
2. In a machine such as described the operating mechanism, such as shown in
Figures 1, 2 and 3 whereby the grinding-wheel is raised and lowered, as required,
and the teeth of the saw are fed forward to an adjustable extent substantially as
described and illustrated in the accompanying drawings.
3. In a machine such as described a supporting table with lateral resilient saw-blade
guides such as illustrated in Figures 1 and 10 in combination with an arrangement
for raising and lowering the saw-blades as required, substantially as described and
illustrated in the accompanying drawings.
4. In a machine such as described a setting device as shown in Figures 5 to 8
operated by means of an abutting disc or cam substantially as described and illus-
trated in the accompanying drawings.
Dated this 26th day of April 1892.
W. P. THOMPSON & BOULT,
Agents for the Applicant.