Improvements in Friction Clutches applicable to Screw Drivers, Cork Screws and other Apparatus.
Year: 1898

page_text: Date of Application, 17th Sept., 1898
Complete Specification Left, 17th June, 1899-Accepted, 16th Sept.,
1899
Improvements in Friction Clutches applicable to Screw Drivers,
Cork Screws and other Apparatus.
I, ALEXANDER THOMSON MACFARLANE, of 58, Hydepark Street, in the County of
the City of Glasgow, Engineer, do hereby declare the nature of my invention to
be as follows:-
This invention has reference to improvements in friction clutches applicable
to screw drivers, cork screws and other apparatus.
The improvements consist in fitting to the body part of these articles an angled
toothed or ratchet wheel, and in having an outer moveable ring disc encircling
the wheel and operated by a handle. Rollers or balls are interposed between the
teeth of wheel and the encircling ring so as to give a friction grip to the latter
in its forward travel and to release in the backward travel.
Springs may be fitted in recesses in the teeth of ratchet wheel.
In the case of a friction clutch for transmitting power a sliding or oscillating
gripping or clutch disc would be thrown into and taken out of gear with the ring
disc by means of an eccentric or cam mounted on shaft and operated by levers
or other suitable mechanism.
Dated the 16th day of Sontember 1898
W. R. M. THOMSON & Co.,
96, Buchanan Street, Glasgow, Agents,
Improvements in Friction Clutches applicable to Screw Drivers,
Cork Screws and other Apparatus.
I, ALEXANDER THOMSON MACFARLANE, of 58, Hydepark Street, in the County of
the City of Glasgow, do hereby declare the nature of my 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: -
This invention has reference to improvements in friction clutches applicable
to screw drivers, cork screws and other apparatus.
The improvements consist in fitting to the body part of these articles an angled
toothed or ratchet wheel, and in having an outer movable ring disc encircling
the wheel and operated by a handle. Rollers or balls are interposed between the
teeth of wheel and the encircling ring so as to give a friction grip to the latter
in its forward travel and to release in the backward travel.
Springs may be fitted in recesses in the teeth of ratchet wheel.

page_text: In the case of friction clutch for transmitting power a sliding or oscillating
gripping or clutch disc would be thrown and taken out of gear with the ring
disc by means of an eccentric or cam mounted on shaft and operated by levers
or other suitable mechanism.
And in order that my said invention and the manner of carrying same into
practice may be properly understood I have hereunto appended two sheets of
explanatory drawings in which the same letters of reference are used to indicate
corresponding parts in all the figures where shown. Figures 1 and 2 are a sec-
tional elevation and horizontal section respectively of a cork screw having my
improvements applied thereto. While Figures 3 and 4 are similar views showing
my improvements as applied to a screw driver. Figures 5 and 6 are a sectional
plan view and transverse section showing my improvements as applied to a friction
clutch. Figures 7 and 8 are similar views of a modified form of friction clutch
from that shown in Figures 5 and 6. Figure 8 being taken on the lines 7-7
and 8-8 of Figure 7. While Figures 9 and 10 are corresponding views showing
my improvements as applied to gear for barring engines.
Referring to these drawings:
In the arrangement of cork screw shown in Figures 1 and 2 the socket end of
screw a is formed with a collar a¹ and on a square continuation of this is mounted
the ratchet wheel 6 having teeth 61 cut, with rollers or balls c fitted therein. The
handle a is formed with a recess to receive ratchet wheel 6 and on end of ratchet
wheel and handle a washer a³ is formed. The action is as follows. When enter-
ing the screw a into a cork the handle a² is moved to and fro which by gripping
on the forward movement of the handle drives the screw into cork, and by releas-
ing on the backward stroke enables the screw to be entered into cork without
shifting the hand. To take off the cork after being drawn, a stop d is passed
through collar a¹ on screw, and by inserting same into hole formed in handle a²
the latter is locked and the cork taken off in the usual manner; a spring d¹ being
fitted to bring back the stop d and unlock the handle.
In the arrangement shown in Figures 3 and 4, illustrating my improvements
as applied to a screw driver, the ordinary driver a is similar to that described
in the cork screw, and a square is formed on same on which is mounted the rat-
chet wheel having teeth 61 cut, and rollers c fitted therein. Fitted into the
handle is an annular piece a engaging with rollers c in ratchet wheel b. The
action is as follows:-To drive a screw, the point is entered into the slot in screw
and the handle as held firmly in hand, and by turning handle to and fro the
rollers can be made to engage and release automatically while the screw is being
forced into position. By cutting the teeth 61 in ratchet wheel in the reverse
manner from that shown a screw driver may be made so that the opposite action
from that described will take place and the screw can be taken out of place.
In the application of my improvements to friction clutches as shown in
Figures 5 and 6, a sliding piece A is mounted on and has motion imparted to it
by the shaft A, the inner end of sliding piece being recessed. The ratchet wheel >>
is mounted loose on the shaft A¹ and has teeth 6' cut in same and rollers or
balls c. The driving pulley B is attached to the wheel b. On the end of the
sliding piece A a recess A2 is formed to receive the ends of levers C or other
suitable mechanism for imparting the sliding motion to same. Springs 62 may be
fitted at the back of the rollers or balls c to keep same against inner face of
sliding piece A. The clutch is shown in gear and the action of working is as
follows: To throw the clutch out of gear, by turning the hand wheel C¹ or other
suitable mechanism the lever C is moved forward on a spindle (and the sliding
piece A is moved back until the recessed part of it is over the rollers e and fric-
tional contact is diminished and allows the sliding piece A to turn with shaft A¹,
and ratchet wheel 6 and pulley B to be stationary Plates 6 are fastened on
ends of ratchet wheel b to prevent rollers e from moving from their true position
on ratchet wheel, and the end of sliding piece A is covered with plate to prevent
grit from entering the working faces.

page_text: In the arrangement shown in Figures and 8, the ratchet wheel b is formed
with teeth 6 of a different section; Figure 8 shows the section. The clutch is
shown in gear and the action of same is as follows:-The rollers o are formed with
a smaller part on which are turned collars c¹ which are moved by the mechanism
as shown on Figure 5 so that by moving the rollers from the position shown into
that on the other side only a rolling action will take place and the shafting will
revolve without moving the driving pulley.
In the arrangement shown in Figures 9 and 10. The ratchet wheel b is
mounted on the shaft A' and has teeth 6¹ and rollers c and round which is an
annular ring A mounted on another shaft A³.
The action is as follows: -Connected to the shaft A³ on which the annular
ring A is formed is the barring engine or other means of moving shaft and con-
nected to the shaft A' on which the ratchet wheel b is mounted is the pinion
gearing with rack on fly wheel or other mass to be moved. On turning the first
shaft A motion is imparted to the second shaft A¹ on which ratchet wheel b is
mounted by the rollers or balls c fitted in same, but should the fly wheel or mass
to be moved move with a greater velocity than the speed imparted to the ratchet
wheel 6 by the annular ring A then the clutch will be automatically thrown out
of gear. A recess may be formed on gear wheel or pinion so that by suitable
levers or mechanism the pinion may be disengaged from the fly wheel or mass
to be moved.
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:-
First. Friction clutches constructed and operated substantially as set forth.
Second. In friction clutches for the purposes described the combination of rat-
chet wheel annular ring disc, and rollers or balls interposed between these, sub-
stantially as set forth.
Third. The combination of screw driver and clutch devices substantially as set
forth.
Fourth. The combination of cork screw and clutch devices, substantially as
set forth.
Dated the 14th June 1800
W. R. M. THOMSON & Co.,
96, Buchanan Street, Glasgow, Agents.