New or Improved Method and Machinery for Cutting or Finishing the Teeth of Gear Wheels.
Year: 1894

page_text: Date of Application, 5th June, 1894-Accepted, 21st July, 1894
COMPLETE SPECIFICATION.
New or Improved Method and Machinery for Cutting or Finishing
the Teeth of Gear Wheels.
I, JOHN LEONARD KUNZ, of 482 Market Street in the City of Milwaukee, in
the County of Milwaukee, in the State of Wisconsin, in the United States of
America, Manufacturer, 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, that is to say :-
My invention relates to an improved method of cutting the teeth on gear wheels,
and also to an improved machine for use in carrying out my improved method.
The object of my invention is to provide suitable means whereby all the teeth
upon a gear wheel may be cut simultaneously.
In the accompanying drawings illustrating my invention,
Figure 1 is a side elevation of my improved gear cutting machine.
Figure 2 is a horizontal sectional view of the same, taken on line 2-2 of Fig. 1.
Figure 3 is a vertical sectional view of the same, taken on line 3-3 of Fig. 1.
Figure 4 is a horizontal sectional view taken on line 4-4 of Fig. 3.
Figure 5 is a vertical sectional view illustrating a somewhat different form of
construction of the die holding device.
Figure 6 is a sectional view of the valve for governing the operation of the
machine.
Referring by letter to said drawings, A designates a suitable base, which is
conveniently made in the form of a suitable cylinder for the reception of water.
A piston B is fitted within the cylinder A, and is arranged to reciprocate vertically
therein, said piston carrying at its upper end, a suitable table B¹. Adjacent to
the sides of the table B₁ are arranged any number of guides C C, which are
arranged to engage in any desired manner, with the said table, so as to guide in its
vertical movement, up or down.
-
.
A socket D is formed centrally in the table B¹ for the reception of an arbor or
spindle d, in the manner shown more particularly in Fig. 3.
This arbor or spindle
is arranged to support the rough casting of a gear wheel while the operation of
finishing the teeth thereon is being performed.
Upon the top of the frame formed by the guides C C, is provided a suitable
head-block E, in the underside of which is secured, in any desired manner, a die
of the exact contour upon its inside to which it is desired to form the outside of the
gear.
In the particular form of construction illustrated in Figs. 1, 3 and 4 of the
drawings, the device for shaping the outside of the gear, carried at the upper end
of the frame, comprises a suitable casting F, which is approximately of the same
shape as the die proper F', and to which said die is secured, in any desired manner,
as by screws or bolts ff.
In the operation of cutting or finishing the teeth of gear wheels by my improved
method, the rough casting G of the gear wheel is arranged upon the arbor or
spindle d, in the manner illustrated in the drawings, being preferably arranged
upon the upper side of a supporting block G', which is preferably of the same
external contour as the finished gear, and is arranged upon the table B' in such
position as to register with the die F¹ in the head-block so that by a vertical
upward movement of the piston and the table, the said supporting block G' will
pass into mesh with the die F¹. In adjusting the casting G of the gear in position
upon the supporting block G', the said casting is arranged with its teeth in register
with the teeth of the supporting block, and it follows that by the described

page_text: upward movement of the table, the casting G will be forced bodily through the
die F', the teeth upon the periphery of said casting being thereby shaped so as to
conform to the teeth of the die.
Water is introduced into the cylinder in base A, through a suitable pipe H
which leads to a force pump and is controlled by a valve H¹ by means of which
the supply of water may be shut off, when the movement of the piston has
..progressed to the desired point, so as to carry the gear entirely through the die.
A second pipe I communicates with the interior of the cylinder, and is arranged to
carry off the water therefrom in order to permit the piston to descend, said latter
pipe being controlled by a valve I' which may be opened when the table B¹ has
reached a predetermined level, when the piston, the table carried thereby and work
-upon-the-table-will-be-permitted-to-descend-by gravity.
In order to effect the stoppage-of-the piston and the parts carried thereby
automatically, I find it convenient to employ an upwardly extending rod J, which
is operatively connected with the lever h, upon the stem of the valve H', upon
which rod is arranged an adjustable collar j adapted for engagement with a
shoulder J¹ upon the table B¹, whereby the rod J may be operated to adjust the
valve H¹ to cut off the supply of water at the instant when the vertical movement
of the piston has carried the gear entirely through the die. As a matter of
convenience I prefer to construct the valve H' in the form of a three-way valve,
the arrangement being such that when the lever h is actuated to cut off the supply
of water, the water from the pump will be permitted to discharge through a relief
pipe, and the operation of the machine thereby stopped automatically without
the necessity of stopping the motion of the pump. By the adjustable arrangement
of the collar jupon the rod J, said collar may be placed at a point upon said rod
necessary to stop the movement of the machine at any desired level.
As a further and separate improvement, I prefer to arrange a suitable lever i on
the stem of the valve 1' and to connect the lower end of the rod K with said lever,
and to provide upon said rod a collar k, adapted for engagement with a shoulder or
stop L, upon the table B', at the instant when the table has reached the limit of
its upward movement, so as to instantly open the valve I' for the escape of the
water from the cylinder. This collar kis conveniently made adjustable in the same
manner as the collar j.
If desired, also, a second collar k' may be arranged upon the rod K, in such a
manner as to be engaged by a shoulder or stop L₁ upon the table, so as to auto-
matically close the valve I' when the limit of the downward movement of the
table is reached, so as to prevent the escape of water from the cylinder.
In the particular form of construction illustrated in Figs. 3 and 4 of the drawings,
the die F is shown as of the same diameter upon its outside as the supporting
block F, to which it is secured, and simply fastened to the lower face of said
supporting block by screws or bolts ff, the block F being also held in engagement
with the head-block E by means of the same bolts or screws.
In some cases, however, it may be preferable to form the supporting block for
the die, in the form shown in Fig. 5, in which a casting M is provided upon its
upper side with a central stud m, adapted to pass through a central aperture e, in
the head-block E, and screw threaded at its upper end as at m¹ for engagement
with a retaining nut. The lower side of this casting M is recessed as at M', and
provided with internal teeth in like manner to the block F, and is counterbored as
at m³ for the reception of the die N.
By this construction, the die and its support may be readily placed in position
in the head-block, by inserting the stud m in the aperture e, and securing the same
by a suitable nut.
The recess M' is of sufficient depth to permit the gear to pass bodily through
the die N as the cutting operation is performed. By the insertion of the die into
the annular opening in the lower side of the supporting block M, a very firm
.support is afforded for the die against lateral strain."
In the usual methods of cutting gear teeth, the teeth are finished separately, and

page_text: he operation is necessarily rendered slow and tedious by reason of the necessity
of the frequent adjustment of the gear during the process of cutting the teeth,.
while by my improvement I am enabled to cut or finish all of the teeth upon a gear
wheel simultaneously, at a given stroke or movement of the piston.
I am therefore, enabled to provide a machine for this class of work having a
much greater capacity for work than any of the ordinary types of gear cutting
machines.
My improved machine is of much simpler construction, and is much cheaper to
manufacture than any of the usual forms of gear cutting machines.
By the employment of hydraulic power for actuating the machine, all the
pressure necessary to cut all of the teeth simultaneously in any desired size of gear
wheel may be obtained.
It will be observed that with the particular arrangement of parts illustrated in
the drawings and herein described, the induction valve will remain closed after the-
piston has been returned to its initial position, so that in order to again start
the machine it becomes necessary for the operator to elevate the rod J so as to
open the induction valve for the admission of water to the cylinder. If desired,.
any suitable device might be employed for enabling the operator to adjust the rod,
although said adjustment may be readily effected by the operator directly grasping
the rod, and moving the same longitudinally, and it is not deemed necessary to
illustrate such operating device in the drawings, as the same forms no essential part
of my present invention.
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. The hereindescribed method of cutting or finishing the teeth upon gear
wheels, consisting in forcing the rough casting or blank from which the gear wheel
is to be formed, bodily through a suitable die, and simultaneously shaping all of the
teeth upon the wheel, substantially as described.
2. The hereindescribed method of cutting or finishing the teeth upon gear
wheels, consisting in forcing the rough casting of a gear bodily through a die, and
simultaneously removing a thin shaving from all of the surfaces of all the teeth,.
substantially as described.
3. The hereindescribed method of cutting or finishing the teeth upon gear
wheels, consisting in forcing a rough casting of a wheel having teeth cast upon its
periphery, bodily through a die, and simultaneously removing the scale from all
of the wearing surfaces of said teeth, so as to give a uniform size and contour to all.
of the teeth upon the periphery of the wheel, substantially as described.
4. A machine for cutting or finishing the teeth upon gear wheels, comprising a
suitable base, a plunger movably engaged therewith, and carrying a supporting
table for the rough casting or blank of a gear, a head-block opposed to said
plunger, a die shaped upon its inside to conform to the outside of the finished
gear, and supported in said head-block in alignment with the plunger, and a
support centrally secured to said supporting table, and shaped upon its outside to
conform to the inside of said die, and adapted to sustain the rough casting of the
gear centrally thereon, whereby a longitudinal movement of the plunger will
operate to force said casting bodily through the die and simultaneously shape or
finish all of the teeth, substantially as described.
Deted this 5th dev of May 1894.
W. H. Beck,
JOHN LEONARD KUNZ.
115, Cannon Street, London, E.C., Consulting Engineer and Patent Agent..