prove in lathes
Year: 1886

page_text: We, MAX FÜRCHTEGOTT STARKE and MORITZ WEINREBE both of the City of
Dresden Manufacturers 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:-
This Invention relates to Improvements in lathes and it has for its object to
lessening the power required to work them and the causing the driving gear to
work with greater steadiness and precision by means of a duplex arrangement of
the transmission in combination with other improvements hereinafter specified,
And in order that our said invention may be fully understood we shall now
proceed more particularly to describe the same and for that purpose shall refer
to the several figures on the annexed sheets of drawings the same letters of
reference indicating corresponding parts in all the corresponding figures.
Figures 1 and 2 of the accompanying drawings represents in plan and elevation
respectively a treadle mechanism for lathes constructed according to our Invention.
Figure 3 is an end elevation of the complete lathe and figures 4 to 12 illustrate
details hereinafter described.
This lathe is provided with a double acting treadle arrangement, whereby dead
points are obviated and with a rest or seat enabling the turner to use both feet
simultaneously. Two treadle levers A A¹ figures 2 and 3 are employed oscillating
on a shaft or centre A* supported by a frame M as indicated more clearly in
figure 4 which represents a side elevation of a portion of one of the said treadle
levers drawn to a larger scale. These levers are provided at their lower extremities
with pedals in the form of rollers 20 and their upper extremities are connected by
steel or other flexible bands B, B1, to a corresponding pair of pulleys or drums C, C¹,
capable of rotating on a shaft J; supported in screwed cone bearings 1 on the end.
standards N figures 2 and 3. Each pulley C, C is provided with a pawl D which
when the pulley is rotated in the forward direction by depressing the pedal of the
corresponding treadle lever is caused by a spring 32 (fig. 4) to engage with a
ratchet tooth on a ring or disc E keyed upon the shaft J. This shaft also carries a
variable speed pulley. K transmitting motion to a corresponding pulley K' on
a shaft mounted on centres 2 which pulley drives the mandril pulley m
figure 3.
The reciprocating rotary motion imparted by the action of the treadle levers to
the pulleys C is converted into a continuous rotary motion of the shaft J by means
of the pawl and ratchet arrangements hereinbefore described as is well understood

page_text: and the levers A A¹ are coupled together by bands F F¹ connected at one extremity
to the pulley C and O¹ and at the other extremity to opposite extremities of a
band G at right angles to the bands F F passing over a pulley H so that when
the pedal on the lever A for example is depressed the band B is unwound from the
pulley C and the band F is wound up on the same pulley whilst the reverse action
takes place with respect to the lever A¹ pulley C¹ and the bands connected there-
with. A steady and regular action of the driving, gear is thus obtained and the
dead points arising from the use of cranks are entirely obviated.
The pulleys Care retained in position upon the shaft J by a shoulder or enlarge-
ment on the said shaft between the pulleys and by the discs E which are fixed
upon the shaft as hereinbefore described. The diameters of the grooves in the
pulleys K K¹ are so regulated that the same length of cord suffices for all the com-
binations except when a small extra pulley L on the shaft J¹ is used which requires
a shorter cord. The combination of the pulleys K K¹ constitutes a duplex
transmission whereby an additional number of changes in the speed may be
obtained.
When the lathe bed is of such length as to render it necessary for the operator
to change his position in order to reach all parts of the work the treadle levers
are made in two parts forming arms oscillating on a shaft extending the whole
length of the lathe. The upper arms which are connected to the pulleys C are
fixed on this shaft but the lower arms carrying the pedals are capable of being
slidden along the shaft to the position most convenient for the turner.
Figure 5 shows one of the pedals in plan and illustrates the manner in which
they are pivoted to the ends of the treadle levers by means of screwed cone
centres 23 in cheeks 22 carrying the pedal rollers 20.
The lathe is provided with an adjustable seat w (figure 3) supported at each end
by bars u one only of which is shown in the drawing capable of sliding longi-
tudinally on bars S to which they are connected by bolts 4 working in slots in the
latter. The bars S are pivoted to the standards N and are capable of being placed
at any desired angle by means of racks T engaging with corresponding studs 3.on
the standards. One of the bars u is provided with holes and the other with
notches as indicated at w¹ figure 3 for the reception of studs or pins 12 on plates v
one of which is shown detached in figure 6 connected to the seat by a screw centre
or pivot 14. The seat w a portion of which is shown in plan in figure 7 and in end
elevation in figure 8 is capable of adjustment upon this pivot by means of a set
screw working in a slot in the plate v and is provided with an adjustable side
rest a sliding in a groove or slot in the back of the seat and capable of being
retained in any required position by engaging with a suitable rack or notch
provided for this purpose.
The lathe is constructed with a table R figure 3 secured by bolts 10, 11 to a
support fixed by bolts 6, 7 to the standards N. The bolt 6 also holds the bed o
which is further secured to the standard by a bolt 5 and carries a poppet head o'.
Figure 10 is an end elevation partly in section and figure 11 a corresponding
longitudinal section (both drawn to a larger scale) of the said poppet head.
The poppet head is secured by clamping bolts to the bed o The spindle neck of
the mandril a works in a bearing provided with grooves and passages for lubrica-
ting as shown in the drawing. The other end of the mandril is supported by a
çonical centre c capable of adjustment by means of nuts d e in the usual manner.
f is a collar fixed on the mandril by a set screw g, and serving to secure a cylinder h
at the back of the mandril pulley m. This cylinder carries a series of four or
other suitable number of concentric rings h h h³ provided with grooves in their
peripheries which can be slipped over the grooves in the pulley m in order to
change the speed.
.;
The mandril bearings are lubricated by means of oil cups n the drip from the
cone bearing being conveyed through a drainage tube o into a cup q placed
beneath in a recess in the standard. The neck bearing is provided with grooves
for the passage of the lubricant as indicated in figure 11 and a short tube z collects

page_text: the oil from the neck and delivers it to a cup q¹ standing in a recess in the front
standard.
The driving cord is controlled by a guide levert pivoted at 8. On the left hand
side of the pivot s there is a slot or recess in the lever t (figure 12) into which a
screw or stop u³ projects in order to limit the movement of the said lever. The
cord is passed through a ring X (figure 10) fixed by a thumb screw y to a bent
rod secured by a set screw w¹ to the lever t.
For controlling the tension of the driving cord a tension pulley 24 figure 3 is
employed, the devices for operating this pulley are illustrated drawn to a larger
scale in plan in figure 9. A bar 26 guided by two brackets 25 and pressed
forwards by a spring 27 is provided with two notches which engage with screws 28
Through the front end of the bar is passed a spindle 29 which can be fixed in
position by a thumb or set screw 30. This spindle 29 carries the tension pulley 24
the driving cord can be tightened or slackened so as to transmit motion or not to
the mandril as required by sliding the bar 26 longitudinally in the brackets or
guides 25.
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,
First. In lathes with duplex transmission the arrangement of two treadle
levers A each provided at their lower extremities with two pedal rollers 20
oscillating on screwed cone centres 23 the said treadle levers being made in either
one or in two parts the lower portions of the levers in the latter case being capable
of sliding along the shaft or centre of oscillation substantially as herein before
described and illustrated in figures 1, 2, 3 and 4 of the accompanying drawings.
Second. In lathes with duplex transmission the combination of the drum or
pulleya c the toothed discs E, the pawls D and the springs 32 with the bands B, G
and F for the purpose of obtaining a steady and constant movement of rotation
substantially as herein before described and illustrated in figures 1, 2, 3 and 4 of
the accompanying drawings.
Third. In a lathe with duplex transmission the arrangement of the corresponding
variable speed pulleys K K¹ in combination with the tension pulley 24 and the
mandril pulley m provided with concentric sliding rings h¹ ª h³ as and for the
purpose substantially as hereinbefore described and .illustrated in figures 3, 9, 10,
and 11 of the accompanying drawings.
Fourth. In a lathe with duplex transmission the arrangement of the driving
cord guide X in combination with the levers v and t substantially as hereinbefore
described and illustrated in figures 10 and 11 of the accompanying drawings.
Fifth. In a lathe with duplex transmission the arrangement of the oil cup
in the recess in the poppet head standard in combination with the oil tube
substantially as herein before described and illustrated in figures 10 and 11 of the
accompanying drawings.
Sixth. In a lathe with duplex transmission the arrangement of the adjustable
seat w with the side supports and sliding bars u substantially as hereinbefore
described and illustrated in figures 3, 5 6, 7 and 8 of the accompanying drawings.
Seventh. The general combination or arrangement of parts forming the improved
lathe hereinbefore described with reference to the accompanying drawings.
Dated this noth dose of Januam1000