Improvements in and connected with Chain Mortising Machines.
Year: 1895

page_text: PROVISIONAL SPECIFICATION.
Improvements in and connected with Chain Mortising Machines.
I, MURRAY HINCKLEY SPEAR of 36 Lime Street, in the City of London,
Engineer, do hereby declare the nature of this invention to be as follows:-
In certain mortising machines as at present constructed it is the custom to feed
the work up to the cutters; according to this invention it is proposed that the work
should remain stationary in so far as vertical movement is concerned, and that the
cutters shonld be fed down to the work. It is a desideratum in machines of this
class that the chain should only travel when work is to be done, and that when the
cutter is to be brought in contact with the wood the contact should be gradual and
not sudden.
To secure the above results it is proposed that the table should be provided with
suitable feed and clamp apparatus in order that the work may be secured at the
desired point. The cutter chain is mounted on a sprocket-wheel and carried over
the depending arm, both the arm and the wheel are carried on a slide capable of
vertical movement. Motion is imparted to the sprocket-wheel by means of a pulley
preferably operated from a friction clutch, and between the shaft of the pulley and
the shaft of the sprocket-wheel is arranged a driving shaft connected by ball
socketed or slide connections, or by a flexible shaft.
The gradual contact between the cutter and the wood may be secured through
the connection of a foot or like lever carrying a connecting lever which in turn is
connected to the sprocket-wheel slide. Mounted upon the connecting lever are one
or more cams arranged to come within close proximity to the inner periphery of a
gear-wheel. Between the cams and the wheel are placed rollers, and the tendency
of the motion of the wheel is to keep said rollers in the slack or open part of the
cam. The gear-wheel itself is driven by a worm actuated by a worm-wheel which
in turn is actuated by a second worm driven by a stepped pulley which in turn
receives its motion from a second stepped pulley mounted on the main driving shaft.
With this construction the gear-wheel first referred to is constantly revolving at
a predetermined speed with relation to that of the driving shaft, if now the foot
lever be depressed so as to cause the connecting lever to move more rapidly than
the periphery of the first referred to gear-wheel, the rollers between the cam and
said wheel bind to prevent the descent of the cutters at a greater proportionate
speed than that due to the face travel of the gear-wheel.
In lieu of the cam and rollers a ratchet and pawl or other arrangements may be
substituted, as one of the main features of the invention is to obtain a mechanical
regulation of the speed beyond which the cutters shall not be fed. The foot or
like lever may conveniently be made to bring into engagement the friction clutch so
that the desired travel of the chain will be secured, as that chain is also fed down
to the work.
Deted the 11th day of February 1895
PHILIP M. JUSTICE,
55 & 56 Chancery Lane, London, Chartered Patent Agent,
For the Applicant.

page_text: COMPLETE SPECIFICATION.
Improvements in and connected with Chain Mortising Machines.
I, MURRAY HINCKLEY SPEAR of 36 Lime Street, in the City of London,
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:-
In certain mortising machines as at present constructed it is the custom to feed
the work up to the cutters; according to this invention it is proposed that the
work should preferably remain stationary in so far as vertical movement is
concerned, and that the cutters should be fed down to the work. It is a desideratum
in mortising machines that the chain should only travel when work is to be done,
and then when the cutter is to be brought in contact with the wood the contact
should be gradual and not sudden.
In order that the invention may be clearly understood reference is made to the
accompanying drawings in which
Fig. 1 represents a side elevation of a mortising machine and partially indicates
some of the improvements.
Fig. 2 is a front elevation.
Fig. 3 is a side sectional elevation.
Fig. 4 is a plan view on line za of Fig. 3.
Fig. 5 is a side elevation showing the invention applied to apparatus in which the
work is fed to the cutters.
In the construction shown in Figs. 1 to 4 the wood or block to be cut is held by
means of clamp 1 against plate 2 carried by table 3 which is capable of being
moved horizontally by means of rack 4 and pinion 5, the latter being carried by
frame 6 which in turn slides on the face of the machine, and can be raised and
lowered by means of adjusting screw 7. With this arrangement it will be seen that
it is possible to adjust at the desired height the material to be cut, and that while
being cut it can be fed horizontally so as to obtain a long slot when that is desired.
It is also possible to feed the work up to the cutting chain as indicated in Fig. 5,
but it is preferred with this construction of machine to feed the chain down to the
work, and with this end in view it is proposed to mount said chain 8 on the driving
or sprocket wheel 9 and carry it around a second wheel 10 carried on a tapered
arm 11 which may be capable of vertical adjustment by means of set screw 12 in
order that the chain may be tightened from time to time if required, or in order
that a longer or shorter chain may be employed. The sprocket wheel 9 and arm 11
are carried by a sliding piece 13 which can rise or fall in the main frame when
actuated by connecting rod 14, lever 15, counterweight 16 and foot lever 17 as will
be hereinafter more fully explained.
Rotation of the sprocket wheel 9 may be obtained from the driving shaft 18
through a universally jointed shaft 19 which would impart motion to sprocket
wheel shaft 20, but instead of shaft 19 being universally jointed it may be rotated
through sliding connections or a flexible shaft may be used, in which case it would
not be necessary to allow for any outward play of shaft 18 as is necessary with
the construction shown in order that shaft 19 may descend. Shaft 18 is driven by
pulley 21 from pulley 22 loosely mounted on the main driving shaft 23 to which is
secured the main driving wheel 24 carrying a friction clutch or surface which will
only engage with pulley 22 when that is forced upon it by means of the movement
of lever 25 so operated with relation to lever 17 that motion is imparted to the
sprocket wheel and chain before the chain is lowered with slide 13. It is in fact
one of the main features of this invention to so arrange mechanism that the
operator shall be prevented from bringing the chain and work together at a greater
speed than has previously been determined on, and this is an essential matter if
sudden shocks and strains are to be avoided. The method of securing this desired

page_text: result as shown in the drawings is as follows:-Mounted on the main driving
shaft 23 is a stepped pulley 26 the belt of which passes around a second like
pulley 27 carried on a worm shaft 28 which drives worm wheel 29 mounted on
worm shaft 30 which gears with worm wheel 31 which is loosely mounted on the
shaft or pivot 32 which carries lever 15. Secured to lever 15 is a lug or cam 33
placed in close proximity to the inner periphery of wheel 31, and said lug or cam
has tapered recesses between which and the wheel are placed rollers 34. Now the
constant rotation of wheel 31 in the direction of the arrow tends to keep rollers 34
in the largest portion of the recesses, and consequently there is no binding action
between them the cam and the wheel. If now the operator attempts to suddenly
depress the foot lever 17 and consequently impart a sudden downward motion to
slide 13 through rod 14 and lever 15, the last named as its lower end rises carries
lug 33 up, and rollers 34 jam between the lug and the wheel. It follows therefore
that the lower end of lever 15 can only rise as rapidly as wheel 31 rotates and that
is governed by the gearing before described. Although this is an efficacious
manner of securing the desired end it is not to be understood that the invention
is limited to this particular arrangement, as the same results can be obtained by
means of a ratchet and pawl, or by other mechanical contrivances.
In the drawings the method by which the friction clutch 22 and lever 15 are
operated from the foot lever is as follows:-Pivoted at 41 on lever 17 is a second
lever 42 provided with slots 43 and 44. In slot 43 rests pin 45 on lever 25 while
slot 44 embraces the pivot point 46 of lever 17. With this construction when the
operator wishes to start the machine he first depresses the outer end of foot
lever 42 which turns on pivot 41, and slot 44 travels up around pivot 46, thus
raising the outer end of lever 25 which being pivoted at 47 throws friction
clutch 22 into contact with driving wheel 24, thus starting the cutting chain,
the slight play of pin 45 in slot 43 not preventing this action. Levers 42 and 17
being thus brought into the same plane are further depressed, the pivot point now
being 46, and thus the chain is lowered to its work as before described, while
slot 43 permits of this motion without in any way affecting the position of the
friction clutch.
To employ the brake or stop mechanism in the cheaper construction of machines
in which the work is fed up to the cutters it is only necessary to connect same to
the upward table feed instead of to the downward cutter feed. In the construction
shown in Fig. 5 the upward feed is secured by means of a toothed segment 48
which gears with rack or screw 7 which passes loosely through guide piece 49 and
is lifted without rotation. When it is desired to raise the work before starting the
machine said screw is turned and segment 48 acts as a nut. When the machine is
to be started the foot lever is employed and the brake or stop mechanism operates
in the same manner as previously described.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. In mortising machines mechanically regulating the speed at which the
cutters and material to be cut are brought in contact, substantially as described.
2. In mortising machines the arrangement of actuating levers in such a manner
that the first movement starts the cutters, and the continued movement brings said
cutters and work in contact, substantially as set forth.
3. The improvements in mortising machines substantially as described and as
illustrated in the accompanying drawings.
Dated the 9th day of November 1895.
PHILIP M. JUSTICE,
55 & 56 Chancery Lane, London, Chartered Patent Agent,
For the Applicant.