An Improved Device for Tightening or Adjusting the Chains of Velocipedes.
Year: 1898

page_text: Date of Application, 11th Mar., 1898
Complete Specification Left, 29th Nov., 1898-Accepted, 21st Jan., 1899
WIELENFABRICK
lands.]
"WILHELMINA," of Zeist, in the Kingdom of the Nether-
An Improved Device for Tightening or Adjusting the Chains of
Velocipedes.
I, DAVID YOUNG, Patent Agent, of the Firm of D. Young & Co., of 11 and 12,
Southampton Buildings, London, W.C., do hereby declare the nature of this
invention to be as follows:-
This invention relates to an improved device which is adapted to be applied to
the rear-wheel axles of velocipedes for tightening or adjusting the chains. With
the known chain-adjusters on the rear fork ends of velocipedes, the axle of the
rear-wheel is generally moved unequally in tightening the chain, so that it is
brought into an inclined position relatively to the crank-shaft or pedal-shaft.
This interferes with good transmission of power to the rear wheel and has also
the effect of rapidly wearing-away the tyre, in many cases even completely destroy-
ing the tyre, since the latter rubs on the tubes or stays forming the rear fork.
The chain-adjuster forming the subject of this invention permits adjustment of
the rear wheel axle in such a manner that the said axle shall always remain
exactly parallel to the crank-shaft or pedal-shaft. The adjustment of the tension
is effected rapidly in the most convenient manner and the improved adjusting
device can also be applied to existing velocipedes.
On each of the two ends of the rear wheel axle is arranged a round or otherwise
suitably-shaped plate outside the fork ends. These plates are provided with a
projection in their central aperture which projection extends into a groove or
notch cut in the said axle, so that, by turning the plates, the axle will be com-
pelled to turn therewith. Between each plate and the fork-end, and between the
nut which firmly connects the axle of the wheel with the frame, and this fork end,
are preferably arranged washers.
The said plates are preferably of exactly the same dimensions and form, and are
milled or grooved at their periphery. They are provided on the inside with a
spiral groove which runs from the centre to or nearly to the circumference. This
groove is preferably made of a slightly dove-tailed form.
The fork ends are formed with longitudinally-arranged axle-ways in the usual
manner. Near the commencement of each of these axle-ways, on the end of the
fork, is provided a projecting pin which fits into the spiral groove in the corre-
sponding plate and is similarly formed slightly dove-tailed.
If the rear wheel be inserted into the fork ends, and the spirally-grooved plates
placed in position on the axle as above described in such a manner that the com-
mencing part of the groove, which is widened for this purpose, comes opposite
the pin, and then the nut is slightly screwed up, the pin will be pressed into this
spiral groove. If now one or both of the plates be turned by hand, which can be

page_text: very easily done by means of the milling or grooves at the periphery thereof, the
axle is also turned and the pin at the ends of the forks force the rear wheel to
move in the axle-ways either forwards or backwards according to the direction
of rotation, and always exactly parallel to the crank-shaft, so. that the two chain
or sprocket-wheels always lie exactly in a straight line and the wheel is in its
proper position in the rear fork.
T
By turning the plates, the rear axle can consequently be always kept at an equal
distance from the pins at both sides of the frame so as to uniformly tighten the
chain. As soon as this is effected, the lock-nuts are tightened; so that the rear
wheel is again firmly connected with the velocipede-frame.
The cones of the rear wheel axle (when these are movable) are secured by lock-
nuts since otherwise they would run back in the rotation of the plates or of the
axle in tightening the chain.
"Toted this 11th date of Manak 1000
An Improved Device for Tightening or Adjusting the Chains of
Velocipedes.
I, DAVID YOUNG, Patent Agent, of the Firm of D. Young & Co., of 11 and 12,
Southampton Buildings, in the County of London, 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:-
_
This invention relates to an improved device which is adapted to be applied to
the rear wheel-axles of velocipedes for tightening or adjusting the chains. With
the known chain-adjusters on the rear fork ends of velocipedes, the axle of the
rear-wheel is generally moved unequally in tightening the chain, so that it is
brought into an inclined position relatively to the crank-shaft or pedal-shaft.
This interferes with good transmission of power to the rear wheel and has also
the effect of rapidly wearing away the tyre, in many cases even completely destroy-
ing the tyre, since the latter rubs on the tubes or stays forming the rear fork.
The chain-adjuster forming the subject of this invention permits adjustment of
the rear wheel-axle in such a manner that the said axle shall always remain
exactly parallel to the crank-shaft or pedal-shaft. The adjustment of the tension
is effected rapidly in the most convenient manner, and the improved adjusting
device can also be applied to existing velocipedes.
4
In the accompanying drawing
Figure 1 is a side elevation, and
Figure 2 a plan of the rear wheel-axle, together with a horizontal section through
the chain-tensioning device, and
Figure 3 is a vertical transverse section of the same on the line I-II, on the
right-hand side of Figure 1.
On each of the two ends of the rear wheel-axle A is arranged a round or other-
wise suitably-shaped plate B outside the fork ends C, C. These plates are pro-
vided with a projection in their central aperture which projection extends into
a groove or notch a formed in the said axle A, so that, by turning the plates, the
axle will be compelled to turn therewith. Between each plate B and the fork-.
end C, and between the nut M, which firmly connects the axle of the wheel with
the frame, and each plate B, are preferably arranged washers m m¹.
C's.

page_text: The plates B, B are preferably of exactly the same dimensions and form, and
are milled or grooved at their periphery. They are provided on the inside with a
spiral or helical groove b which runs from the centre to or nearly to the circum-
ference. This groove is preferably made of a slightly dove-tailed form.
The fork ends C are formed with longitudinally-arranged axle-ways D in the
usual manner. Near the commencement of each of these axle-ways, on the
end C of the fork, is provided a projecting pin E which fits into the spiral groove b
in the corresponding plate B, B, and is similarly formed slightly dove-tailed.
If the rear wheel be inserted into the fork ends, and the spirally-grooved plates B
placed in position on the axle A as above described in such a manner that the
commencing part 61, Figure 1 of the groove b; which is widened for this purpose,
comes opposite the pin, and then the nut M is slightly screwed up, the pin E will
be pressed into this spiral or helical groove. If now one or both of the plates be
turned by hand, which can be very easily done by means of the milling or grooves
at the periphery thereof, the axle is also turned and the pins E at the ends of the
forks force the rear wheel to move in the axle-ways D either forwards or backwards
according to the direction of rotation, and always exactly parallel to the crank-
shaft, so that the two chain or sprocket-wheels always lie exactly in a straight line
and the wheel is in its proper position in the rear fork.
By turning the plates, the rear axle can consequently be always kept at an equal
distance from the pins E at both sides of the frame so as to uniformly tighten the
chain. As soon as this is effected, the lock-nuts M are tightened; so that the rear
wheel is again firmly connected with the velocipede-frame.
The cones of the rear-wheel axle (when these are movable) are secured by lock-
nuts, since otherwise they would run back in the rotation of the plates or of the
axle in tightening the chain.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, as communicated to me by
my foreign correspondent, I declare that what I claim is:-
The improved chain-adjuster comprising the discs or plates mounted on the axle
of the driving-wheel and cach provided with a spiral or helical groove the con-
volutions whereof continually recede from the said axle, and pins on the frame
of the machine in engagement with the grooved discs or plates respectively, sub-
stantially as herein before described.
Dated this 29th day of November 1898.
D. YOUNG & Co.,
11 and 12, Southampton Buildings, London, W.C.,
Agents for the Applicant.