Improvements in Flexible Shafting for Transmitting Rotary Motion, and in Coupling Attachments therefor.
Year: 1891

page_text: Date of Application, 30th Nov., 1891-Accepted, 5th Mar., 1892
COMPLETE SPECIFICATION.
Improvements in Flexible Shafting for Transmitting Rotary Motion,
and in Coupling Attachments therefor.
We, Joux MOFFAT, of Irvinebank, Queensland, and Bridge Street Sydney,
New South Wales, Tin-smelter, and WILLIAM WRIGHT VIRTUE, of Bridge
Street Sydney aforesaid, 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 :-
These improvements relate to sectional or jointed shafts with flexible couplings,
for transmitting rotary motion to shearing machines and certain other portable
machines and implements, and to other mechanisms which in operation are moved
about relatively to the point from which driving power is derived. And they also
relate to coupling attachments for connecting the ends of such shafts to the
machine to be driven, and to the driving shaft respectively.
The invention embraces two modified constructions of shaft. In the first design
the shaft is in two rigid sections, which are united with one another and with the
mechanism from which power is derived and with the machine to which power is
being transmitted with flexible connections. In the second design the shaft is
formed in three or more sections, united together by means of special constructions
of universal flexible joints.
In the sheet of explanatory drawings annexed, Figures 1 to 14 relate to the first
design, and Figures 15 to 20 to the second design of shaft.
Figure 1 is a longitudinal section through the shaft and its attachments,
Figure 2 a side elevation thereof,
Figure 3 enlarged longitudinal section through the clutch gear at the driven end
of the shaft,
Figure 4 end plan of the socket of the clutch gear,
Figure 5 side elevation thereof,
Figure 6 side clevation of the stem and key of the clutch gear,
Figure 7 transverse section taken at the head of the clutch stem,
Figure 8 rear side elevation of the lower casing of the elbow joint,
Figure 9 longitudinal section through the lower section of the "elbow" joint
casing enlarged;
Figure 10 longitudinal section through the upper section of the elbow joint
casing enlarged,
Figure 11 top plan of part shewn in Figure 9,
Figure 12 longitudinal section through the casing of the "shoulder” joint and
part of the head bearing of the shaft,
Figure 13 plan of the head clutch socket,
Figure 14 longitudinal sectional elevation through the clutch on the head of the
shaft,
Figure 15 longitudinal section through the head or shoulder joint, one of the
intermediate joints, and the "wrist" coupling of the second design of shaft,
Figure 16 side clevation of same,
Figure 17 longitudinal section through one of the intermediate joints,
Figure 18 longitudinal section through an improved construction of one of the
intermediate joints,
Figure 19 longitudinal sectional elevation through the coupling shewn in
Figure 18,
Figure 20 transverse section through the centre of the coupling.
We will now describe the first design of shaft.
D
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page_text: integral with the part 2, 4 helical spring scated in a cup on the part 2, 5 clutch
shaft, 6 key pins set in the part 3, 7 clutch tube, 8 bayonet slot in part 7, 9 socket
of clutch gear, 10 screwed end of part 7, 11 collar on part 18 tapped, 12 bushing,
13 collar on part 12, 14 stem of clutch, 15 oil spaces, 16 key of clutch, 17 bearing
section of main shaft, 18 sleeve, 19 screwed end of part 12, 20 casing or sheath
tube, 21 reduced section of main shaft, 22 screwed ends of part 21, 23 oil chambers,
24 bearing section of main shaft, 25 bushing, 26 screwed ends of part 27,
27 reduced section of main shaft, 28 sheath tube, 29 bearing section of shaft,
30 screwed end of same, 31 bevil pinion, 32 sleeve or tubular extension of the
lower section of the elbow joint casing, 33 hollowed portion of the lower check of
the part 32, 34 guard check of the part 32, 35 circular slot in the cheek 34,
36 upper section of the elbow joint casing, 37 upper jaw of the part 36, 38 oil hole,
39 pin, 40 reduced part of same screwed, 41 turned end of pin 39, 42 bevil wheel,
43 bevil pinion, 44 screwed end of bearing section 45 of shaft, 46 collar on
bushing 47, 48 sleeve or tubular extension of upper section of elbow joint casing,
49 shoulder, 50 screwed end of reduced section of main shaft 51, 52 sheath tube,
54 reduced section of shaft, 55 screwed end of shaft section 54, 56 clutch socket,
58 slot in part 56, 59 collar on end of part 56, 60) stem, 61 feather or spline,
62 screwed end of part 60, 63 coupling locking points, 64 lower section of shoulder
coupling, 65 claws or hooks of shoulder coupling 64, 66 motion block, 67 motion
pivots, 68 snap spring for locking the pivots 67 in the claws 65, 69 sleeve or
tubular extension of the lower casing of the shoulder joint and clutch mechanism,
70 lower spring barrel and guard integral with the part 69, 71 cup piece, 72 helical
spring, 73 helical ridges cut in the part 70 to fix the spring thereto, 74 upper
spring barrel and guard, 75 shoulder thereon, 76 neck piece integral with the
parts 74 and 75, 77 reduced screwed end of driving spindle, 78 oil tube, 79 collar
on driving spindle supporting the part 74, 80 driving spindle, 81 driving spindle
bearing.
The parts 1 and 2 are of well-known construction and are in common use in
connection with sheep-shearing machines. The spring 4 serves to keep the
bayonet catch which secures the parts 3 and 7 locked. There is a bayonet slot 8
on each side of the part 7 into which the double key pin 6 gears. The part 9 is a
cup turned in an enlarged part of the clutch shaft 5, from which cup two triangular
pieces are cut as indicated in Figures 4 and 5. The end of the part 7 is screwed
at 10 on to the lower end 11 of the union piece 18, sufficient free clearance being
allowed for the collar 13 of the bushing 12. The stem 14 is made to fit on to the
part 9; the ends of the key 16 come in contact with the vertical faces of the
part 9,
The collar 15 bears against the collar 13. When the shaft is uncoupled
from the machine, the parts marked 1 to 9 remain with the machine. There is
sufficient surplus clearance provided in the part 9 to permit the locking of the
bayonet catch. The part 18 is rotatable about the part 12, but the part 20 is
screwed or brazed to the part 12. This construction of machine coupling and
clutch has many special advantages; it provides a very solid connection and
permits coupling and uncoupling to take place whilst the shaft is in motion.
In practice a shaft for the sheep-shearing machine should be provided with one
bushing 25 in the lower section, and two such bushings in the upper section. The
shaft proper or core may be formed in one piece or in a number of pieces screwed
together as shewn, a thick section being provided wherever there is a bushing.
The casing or sheath is screwed or brazed to the bushings. Oil holes are provided
in the casing between every bushing. The bevil pinion 31 is screwed on to the
upper end of the shaft section 29 and forins a collar thereon; it gears into the
wheel 42, which in turn gears into the pinion 43. The construction of the elbow
casing will be readily understood; it has been specially designed to cover and
protect as far as possible the wheel and pinions through which the motion is
transmitted. The amplitude of motion which the elbow joint permits is slightly
greater than that which can be attained by the elbow of a man's arm.
The part.28 is screwed or brazed.to the part 32, the -part 52 to the part 47, and

page_text: the corresponding parts of the shaft in a similar manner. The end 55 of the
shaft 54 is screwed into the end of the clutch-socket 56, the construction of which
is shewn in detail in Figures 13 and 14. In the latter figure also the construction
of the stem 60 of the clutch-gear is shewn; this stem fits the interior of the part 56
and is provided with a spline pin or feather 61 which slides in the slot 58 in the
socket 56. The overhead or driving spindle 80 is connected with the part 60 by a
universal joint, and the motion is communicated from the latter to the shaft by
means of the spline 61 and the socket piece 56. The collar 79 supports the part 76
which is integral with the part 74. On to the latter the helical spring 72 is
screwed, the end being clipped as shown. The lower end of this spring is screwed
in like manner on to the barrel 70 which is integral with the part 69. When the
shaft is to be detached from the overhead connection, the parts 69 and 70, which
are integral with one another, are screwed back off the spring 72; when this part
of the connection is adrift, the part 60 with its feather slips out of the socket 56.
The parts are replaced by a reverse operation. The spring 72 supports the whole
weight of the shaft and its attachments and allows a universal motion of about 40°,
which is found ample for all practical purposes but may be increased if desired.
The coupling is preferably of the ordinary block and pivot type. The modification
of that construction shewn in Figure 1, or that shewn in Figure 19, may, however,
be used instead. The snap springs 68 prevent the coupling hooks coming out of
gear with the motion pivots. The hooks 65 take the place of the eyes in the
cominon coupling; they are made sufficiently large in the mouth to be easily
hocked on to the motion pins. The coupling is hooked together before it is
connected with the shaft. The ends of the shaft are prolonged as shewn at 63 to
form a lock for the parts when the same have been put together.
An oil tube 78 is fitted as shewn in Fig. 12; it is made sufficiently high on the
outside to feed oil higher than the level of the the collar 59; the leakage of oil
past the part 56 will generally be found sufficient to lubricate the whole upper
section of the shaft.
The description following refers to the second design of shaft.
Referring to Figures 15 and 16, 94 is the tail shaft of a shearing machine or
other apparatus as aforesaid, 95 reduced part of such shaft screwed, 96 locking
horn or point, 97 tail shaft bearing; 98 sleeve thereon, 99 hub or coupling screwed
on to the part 95 and acting as a collar to keep the parts 94, 97, and 98 in position
relatively to one another, 100 claws of coupling, 101 motion block, 102 motion pins,
103 hub of upper coupling claw, 104 trunnion pins on part 98, 105 bayonet sleeve
secured to the end casing of the shaft, 106 bayonet jaw, 107 screwed end of shaft,
108 neck or stem of sleeve 105 screwed to the shaft casing 111, 110 shaft core,
112 neck or stem of cup 113 screwed on to the part 111 and forming a bearing for
the shaft section which passes through it. 114 helical Spring in compression,
115 hub of intermediate coupling hook, 116 claws of hook, 117 motion block,
118 motion pins, 119 coupling hook, 120 neck or stem of sleeve 121, 122 trunnions
on part 121, 123 screwed end of shaft, 124 hub of coupling hook, 125 claws on
same, 126 motion block, 127 motion pius, 128 hub of coupling hook, 129 screwed
end of driving spindle 130, 131 bayonet sleeve rotatable on the part 130, 132 collar
screwed on to the head bearing 133 and supporting the sleeve 131 and through it
the whole shaft.
Referring to Figure 17, 82 are the shaft cores through which power is trans-
mitted, 83 casing tubes, 84 oil spaces, 85 necks of sheath cups 86, 87 lips on
parts 86, 88 helical spring in compression, 89 helical ridges on the parts 86 to grip
the spring 88, 90 body of coupling hooks, 91 claws of same, 92 motion block,
93 motion pins. This form of joint casing may be used generally in connection
with universal joints. The cups 86 are made to very nearly enclose the joint as
shewn and so afford it better protection and prevent the spring 81 from fouling it;
they may also be made so as to prevent undue flexion of the joint by meeting at the
edges when the limit has been attained.
Referring to Figures 18, 19, and 20, 135 is the shaft core, 136 the casing tubes,

page_text: 137 oil space, 138 cup ring screwed on to the shoulder ring 139, 140 shoulder on
ring or sleeve 139, 141 bushing screwed into the end of the tube 136, 142 collar on
the end of the bushing 141, 143 helical spring in compression, 144 motion block,
145 motion pins, 146 coupling hooks, 147 hubs of same, 148 conical ring washer,
149 locking horns or points, 150 cup corresponding with the cup 138.
The shaft is made in as many sections as may be required, each preferably
about six inches long. The flexion of the joints should not be permitted to
exceed 40°..
The spaces between the shaft and the casings form oil chambers which are fed
through oil caps in the casings. In operation, the driving spindles are usually set.
overhead. When this is so the oil fed into the oil chambers lubricates the lower
bearing of the casing, and the leakage therefrom serves the coupling and the upper
bearing of the section next below if the leakage should be insufficient for this
purpose lubrication of the upper bearing may be effected by elevating the lower
end of the shaft so as to make the oil run towards the head. The rings 148 are of
soft metal and are seated in recesses in the end bearings 141 to which they are
fitted. The ends of the springs 143 are bent in and pass through holes bored
through the ring 139 and the tube 136 which are thus locked together;
otherwise they are made to pass through the base of the cup as shown in
Figure 1.
Both claw hooks of cach pair are identical in construction. The months are
sufficiently wide to admit the motion pins into them; these pins are subsequently
secured in and prevented from becoming unlocked from the claws of the hooks
by the horns which are formed on the ends of the shaft to which the claws are
secured by screwing, and which extend almost to the motion block. The coupling
can be immediately taken apart by screwing back the claws whereby the horns are
withdrawn and the jaw left open. The helical springs which enclose the joints
are arranged so as always to be in compression; and they are sufficiently strong to
exert upon the couplings the degree of tension necessary to prevent "kinking" and
to prevent undue flexion of the shaft. The construction of the parts adjacent to
the driven machine must be adapted to operate with the tail shaft and tail bearing
thereof. In uncoupling the shaft shewn in Figures 15 and 16 from the machine,
the parts 98 and 108 are grasped, one in each hand, and pulled apart (thus
throwing the helical springs which enclose the joints into compression), and are then
twisted relatively to one another so as to disengage the trummion pins 104 from the
jaws 106. The claw 103 which has jaws open permanently may then be unhooked
off the motion pins 102. These parts are re-coupled by a reverse operation and
are maintained in working position by means of the helical springs.
construction of the head coupling and the method of latching and unlatching it is
practically identical.
The
If the helical springs are made sufficiently stiff it will be unnecessary to use the
locking horns. It is preferred, however, that only one claw of each pair should be
provided with these attachments, in order that any one of the couplings may be
taken adrift without unscrewing the claws.
The bases or hubs of the claw hooks form collars on the shaft sections, and take
against the end bearings of the casing tubes and prevent end play of the shaft
cores therein, except in the case of the cores at the extreme ends which are made of
surplus length to allow of the coupling and uncoupling of the bayonet catches at
the ends of the shafts.
In an alternative construction, casing tubes are not used, but collars are secured
to the shaft cores and against such collars the bases of the parts 85, 108, 112, or
their equivalents bear. In such a construction the springs operate as previously
described. It is preferred, however, that the section of shaft next the driven
machine should be encased.
The conditions which the helical springs should fulfil are, to resist elastically
flexion of the shaft at the joint at which they are fixed, and to operate together to
keep the joints or couplings in tension by bringing about a tendency to separate the

page_text: When
several sections from one another. When the bayonet coupling gear shewn in
Figures 15 and 16 is used, it is essential that the construction be such that the
sleeve 105 may be slid back relatively to the shaft 110 and the sleeve 98.
the section of shaft next the machine is encased the construction shewn in
Figure 15 is employed, but when it is not encased a collar or ring is fixed upon the
shaft and a helical or volute spring is placed around the shaft, bearing at one end
against such collar or ring and at the other against the part 10s. The operation
of locking and unlocking is in such case performed in a mauner precisely similar to
that before described.
In lieu of the bayonet coupling gears described, spring couplings as employed for
the intermediate joints may be used.
Horns such as 63 may also be used for the purpose of locking the ordinary hook
and eye coupling used in some forms of flexible shafts.
We are aware that flexible or jointed shafts are known which consist of two
rigid sections provided with shoulder, elbow, and wrist flexible connections, and we
do not claim such a combination broadly as our invention. We do not, however,
restrict ourselves specifically to the construction of the several parts as described
herein and as illustrated in the drawings, the mechanical details generally being
capable of modification and variation within the limits of the invention as set forth
in the claiming clauses which follow.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be used, we declare that what we
claim is :-
1. The combination of a tube or bushing 3, and a shaft 5 rotatable therein, both
of which parts are in mechanical connection with the driven machine, a coupling
between the shaft 5 and the main shaft and adapted to allow surplus longitudinal
play, one or more locking pins on the part 3, a bayonet slot in the casing of the
main shaft, and a spring to keep the bayonet joint locked, substantially as
described.
2. A clutch for the purposes set forth constructed substantially as described
with reference to Figures 3 to 7 of the drawings.
3. The combination of the parts marked 5, 9, 14 and 16 in the drawings,
substantially as described.
4. The combination of the parts marked 2, 3, 4, 5, 6, 7, 8, and 17 in the
drawings, and a coupling between the parts 5 and 17, substantially as described.
5. The construction of the elbow joint casing substantially as described and as
illustrated in Figures 8 to 11 of the drawings.
6. The combination of the elbow joint and elbow joint casing, constructed and
operating substantially as described with reference to Figures 1 and 2 and 8 to 11
of the drawings.
7. The combination of the parts lying between the part marked 21 and the
driven machine, substantially as described and as illustrated in Figures 1 to 7 of
the drawings.
8. The combination of the slotted socket 56 secured to the head of the core or
rotating part of the shaft and moving in the part 69, the stem 60 secured to a
shoulder joint, a spline or feather on the part 60, and a resilient and flexible support
for the part 69, substantially as described.
9. The combination of the parts marked 56, 60, 61, 69, 70, 72, 74, 76, 80,
and 81, and a universal coupling between the parts 60 and 80, substantially as
described.
10. The combination of the parts lying between the parts 52 and 54 and the
parts 80 and 81, substantially as described with reference to Figures 1, 2, 12, 13,
and 14 of the drawings.
11. The combination of the parts marked 70, 72, 74, 54, and 80 in the
drawings, and a universal joint between the parts 54 and 80, substantially as
described.

page_text: 12. The combination with the part 70 as illustrated, of an oil tube 78, sub-
stantially as described and for the purposes set forth.
13. A flexible shaft consisting essentially of a number of shaft sections cach
encased in sections of tube, said sections of shaft being united in a universal joint
or coupling, and said sections of tube secured together at the ends by helical
springs which are set as to resist elastically flexion of the shaft and to tend to set
its sections in line with one another, substantially as described.
14. A flexible tube for enclosing or encasing a flexible shaft, consisting of a
number of rigid sections held together by such shaft or by couplings connecting
the parts thereof and secured at the ends by helical springs, which are so set as to
elastically resist flexion of the shaft and to tend to set its sections in line with one
another.
15. The combination of shaft sections 82, universal joints or couplings uniting
the same, tubes 83, bearings 85, and spring 88 in compression, with or without the
horns such as 149, substantially as described.
16. A flexible jointed shaft comprising sections of shaft encased in sections of
tube carrying end bearings, the spaces between the shafts and the tubes forming
oil reservoirs, and said sections of shaft and of tube being united with universal
joints or couplings and springs, respectively, substantially as described and
illustrated.
17. The combination of shaft sections 135, horns or projections 149, claw
hooks 146, motion block 144, and motion pins 145, substantially as described.
18. In a flexible shaft coupling of the hook and eye type, the employment of
horns or projections such as 63 to form a lock, substantially as described.
19. The construction of a universal coupling substantially as described with
reference to Figures 18 to 20 of the drawings.
20. A flexible shaft consisting essentially of a number of shaft sections united
together with universal couplings and with springs which keep the couplings in
tension and offer au elastic resistance to the bending of the shaft.
21. The combination of shaft sections such as 82, cups or barrels such as 86
integral with bearings 85 for the shaft sections, a flexible joint between the shaft
sections, a spring such as 88 in compression secured to the cups or barrels 86, and
collars secured to the shaft sections 82 and in contact with the bearings 85,
substantially as described.
22. The combination of the sleeve 98 having trunnions or pivots 104, bayonet
sleeve 105 integral with or secured to the shaft casing 111, shaft section 110
capable of endwise movement in the casing 111, a universal coupling between the
shafts 94 and 110, and a spring 114 operating as described.
་
23. The combination of a fixed bearing 133, a sleeve 122 having bayonet jaws
which grasp the trunnions or pivots 127 on the shaft sleeve 121, shafts 110 and 130
and a universal coupling connecting the same, and springs 114 operating as
described.
24. The combination with the sleeve 105 and the parts therewith connected
and operating therewith, of a collar fixed rigidly to the shaft 110, and a helical or
volute spring in compression between such collar and sleeve, substantially as
described.
T
11
2
W. LLOYD WISE,
Per F. J. Brougham,
46, Lincoln's Inn Fields, London, W.C., Agent for the Applicants.