Improvements in Engaging and Disengaging Gear for Machine Belts and Ropes.
Year: 1892

page_text: Date of Application, 12th Sept., 1892-Accepted, 22nd Oct., 1892
COMPLETE
SPECIFICATION.
Improvements in Engaging and Disengaging Gear for Machine
Belts and Ropes.
I, WILHELM MAYBACH, of Cannstatt, in the Kingdom of Württemberg, in the
German Empire, Engineer, 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 :-
My invention relates to an engaging and disengaging gear for machine belts and
ropes, by means of which the belt or rope, when thrown out of gear, is removed
entirely or almost entirely out of contact with the pulleys. My invention also
consists, further, of means permitting only one of several change-belts or -ropes to
be thrown into gear at a time.
My invention will be more readily understood by reference to the accompanying
drawings, in which :
Fig. 1 is an elevation showing two pulleys and a horizontal belt connecting the
saine, and the means for holding the belt out of contact with the pulleys.
Fig. 2 shows the position of the parts when out of gear.
Figs. 3 & 4 are views corresponding to Figs. 1 & 2 of another form of construction,
in which a vertical belt is employed.
Fig. 5 is an elevation showing my improved engaging and disengaging gear for
change-belts or -ropes.
Figs. 6 & 7 are diagrams illustrating two additional positions of the main parts
of the gear shown in Fig. 5.
Fig. 8 is a front elevation representing a modification of this gear, as employed
for four change-belts.
Fig. 9 is a detail side elevation showing the coupling-handle of this gear and the
parts directly connected to the same.
Fig. 10 is a detail sectional elevation of the same parts.
Similar letters denote similar parts throughout the several views.
In Figs. 1 & 2 A is the driving and B the driven pulley, C a tension-roller
adapted to be swung around the pivot P by means of the handle H, e is the belt,
D a solid or at least stiff casing or frame parallel to the belt when the same is
driving the pulley B, and d a rest suspended from the axle of the roller C.
In order to throw the pulley B and the belt e into gear, the right end of
handle H is raised, and the roller C pressed on the belt e, as shown in Fig. 1.
When wanting to disengage the belt, the right end of handle H is depressed, and
the tension-roller C raised, so as to lift simultaneously the portion of the belt e
next to the rest d. The lower half of the belt, in consequence of its weight, will
sink and rest on the casing D, and the side portions will also entirely, or for great
part, lay themselves against the said casing, in consequence of their natural stiffness
(see Fig. 2). The belt e will thus be entirely or almost entirely out of contact with
the pulleys A and B, and the friction and attendant wear will be considerably
reduced or altogether avoided.
In Figs. 3 & 4 I have shown another form of construction in which the pulleys
are located one above the other. The construction in itself is distinguished from
that before described merely by the addition of a stationary rest. D₁ between the
pulleys A and B and opposite the displaceable rest d.
The operation of this mechanism is as follows: Throwing the parts into gear is
accomplished as before described: In order to disengage the belt e, the upper end
of the handle H is turned to the left so as to discontinue the pressure exerted on the
belt by the tension-roller C. The lower portion of the belt e will slip off the
pulley B and lay itself on the lower circular portion of the casing D, owing to its
own weight. The middle portion of the belt will rest on the rests D and d

page_text: respectively. The upper portion, owing to the stiffness of the belt, will bend
slightly outwards so as to come in contact with the upper circular end of the
casing D. The effect of this arrangement is exactly the same as before described,
namely to reduce or to remove entirely the friction between the belt and the
pulleys.
It will be obvious that these two forms of construction may be employed for
belts and ropes inclined at any angle.
I will now describe the means which I employ for engaging and disengaging
several change-belts or -ropes in such a manner, that only one of them can be
engaged at a time. In Figs. 5 to 7 I have shown the construction of this means as
employed for two change-belts, and Figs. 8 to 10 illustrate a modification in which
four change-belts are used.
Referring to Figs. 5-7, A¹ A" are the driving and B₁ B" the corresponding
driven pulleys; ee" are the driving-belts, and CC the corresponding tension-
rollers. These rollers are pivoted at the ends of levers and respectively, both
loosely and independently mounted on a shaft l. The rear ends of the double-
armed levers are constantly drawn upwards by means of springs m¹ and m
respectively. The levers and are linked to cranks g' and g" respectively by
means of connecting-rods k¹ and ", the ends of which are joined to the levers
between the shaft and the tension-rollers. The cranks g¹ and 9" are mounted on a
shaft G and form with each other an angle of about 60°. H is a handle by means
of which shaft G may be turned, and is formed with a disc m having a cam n,
adapted to snap into a recess, o', of the spring o, secured at r.
The operation of this mechanism is as follows: When the handle H is in the
extreme right position (Fig. 5), the roller C¹ is depressed and the roller C¹¹ raised,
that is to say, the belt el is engaged with the pulleys A' and B₁, and the belt ell
disengaged from the pulleys A and B. When throwing the handle H over to
the left into the central position illustrated by Fig. 6, both the rollers C¹ and C
will be raised and both the belts e¹ and e" disengaged. The handle H is locked in
this position by the cam n snapping into the recess o¹ of the spring o.
When
throwing the handle H full over to the left, the roller C₁ will be raised and the
belt e' disengaged, whereas the roller C will be depressed and thrown into gear,
as shown in Fig. 7.
The action of the springs m¹ and m presents the peculiarity that when one of
the rollers C and C is depressed, both springs keep the same on the belt; for
instance when the roller C¹ is depressed (Fig. 5), the spring m³ presses the same
downward directly, the spring m tends to depress the roller C" and to draw the
crank " downwards by means of the connecting-rod ". The shaft G will thus
be subjected to a torsional strain, and the crank g¹, being secured to the shaft, will
be depressed, exerting a downward pressure on the lever and the roller C'. The
same effect will occur when the roller C is raised, and the roller C" depressed, as
will be understood with reference to Fig. 7. When the handle H is in the middle
position (Fig. 6), the cranks g' and g₁ are situated symmetrically to the handle,
so that the springs m' and m¹ will each tend to turn the handle in another direction
with the same force; the spring o, therefore, will easily be able to hold the handle
in this position.
It will be obvious that the two springs m¹ and m" may be replaced by a single
spring secured to the disc m at a point between the cranks g¹ and g" or between
their continuations, on the opposite side of the disc m. It will be further obvious
that the connecting-rods k¹¹¹ may be joined to the levers at the ends, where
the springs m' m" are fastened in the construction illustrated by the drawings; in this
case the springs m' ml would be secured to those arms of the levers i¹¹, on which the
tension-rollers CC'" are provided. I may also secure the springs m¹ m" on
the same side of the shaft on which the tension-rollers C' C are located, the
springs being constructed in such a manner as to exert a downward pressure on the
levers and ".
In Figs. 8-10 I have illustrated the construction of my improved gear as

page_text: employed for operating four change-belts. The pulleys, belts, tension-rollers, the
levers to which the latter are secured, and the springs depressing said levers are not
shown in these figures, being arranged substantially as illustrated by Fig. 5 and
described with reference thereto. The connecting-rods are joined to
the cranks ggg on the cranked shafts G G¹. The cranks g' and g" form
with each other an angle of about 60° (as in Fig. 5), and the relative position of the
cranks and is a similar one. The inner ends of the shafts G G₁, which almost
touch one another (see Fig. 10), are provided with toothed wheels hh. Each of
these wheels is provided with a circular flange 7 projecting beyond the face of the
teeth, except on a short portion of the periphery, where it is cut off, as shown at q',
Fig. 9. Opposite this notch 7' a cam n is secured to each of the toothed wheels h
and h, this cam being adapted to snap into a recess o' of the spring o, as already
described. The handle H is located above the toothed wheels and h¹, and
provided with a toothed disc p which may be brought into gear with either of the said
toothed wheels by shifting it laterally to this end, the disc p is loosely mounted on
its shaft p', or the shaft itself may be shifted together with the disc.
This mechanism is operated as follows: In order to engage one of the belts
operated by the cranks g" and 1, while either of the other two belts is engaged, the
handle H, which in this case is placed directly above the toothed wheel h, is
raised to the vertical position, Figs. 9 & 10. The cranks and are thereby
brought into the elevated position shown in Figs. 8 & 6, and the corresponding
belts disengaged from the pulleys. The cam n of the toothed wheel / will snap-
into the recess o¹ of the spring o, and the cranks and will be locked in their
position. The notch q' will assume the only position in which it permits of the.
disc p being shifted sideways, so that the latter may be brought to engage with
the toothed wheel '; the notch q¹ of this wheel is of course in the same position
as that of the toothed wheel, as both the cranks gl and 911 are elevated, and the
corresponding belts disengaged. It will be obvious that by turning the handle H
downwards to the right or to the left either of the belts operated by the cranks gl
or gill may be thrown into gear with the corresponding pulleys. It will be further
obvious that only one of the four belts can be engaged at a time.
This mechanism for operating four change-belts is obtained merely by a dupli-
cation of the mechanism shown in Figs. 5-7 and by making the handle H
displaceable laterally.
Instead of providing the flanges on the wheels h h', I may form the disc with
a circular flange having an appropriate notch.
I wish it to be understood that the devices illustrated by Figs. 1-4 m
may be
applied to the mechanisms represented in Figs. 5-10, and I prefer to employ these
devices in any case where belts or ropes are brought to engage with their pulleys
by means of tension-rollers.
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 combination, with a driving and a driven pulley, a belt or rope placed on
the same, and a pivoted roller adapted to throw the belt or rope and pulleys into
gear, of a rest connected to the roller and adapted to remove the belt or rope
from the pulleys, and a casing adapted to support the greater portion of the belt
or rope, when the same is disengaged, for the purpose set forth.
2. The combination, with the driving pulley A, the driven pulley B, the belt or
rope e, and the tension-roller C pivoted by means of the handle H, of the rest d,
adapted to be displaced together with the roller C, and the casing D, substantially
as and for the purpose described.
3. The combination, with the driving pulley A, the driven pulley B, the belt or
rope e, and the tension-roller C pivoted by means of the handle H, of the rest d,
adapted to be displaced together with the roller C, the casing D and the stationary
rest D', substantially as and for the purpose described.

page_text: 4. An engaging and disengaging gear for change-belts and -ropes, by means of
which but one of the belts may be thrown into gear at a time, for the purpose
described.
5. In an engaging and disengaging gear for change-belts and -ropes, the combi-
nation, with the pulleys, belts or ropes, and tension-rollers, of means for elevating
and depressing the rollers in such a manner, that only one of them may be thrown
into gear at a time, for the purpose set forth.
6. In an engaging and disengaging gear for change-belts and -ropes, the combi-
nation, with the driving pulleys A' A", the driven pulleys B' B", the belts e ell,
the levers, and tension-rollers C₁ C, of springs tending to press the rollers
on the belts, connecting-rods, the cranks and o", forming an angle with
each other, the shaft G, handle H; and means for locking the same in its middle
position, for the purpose set forth.
7. In an engaging and disengaging gear for change-belts and -ropes, the combi-
nation, with the driving pulleys A₁ A", the driven pulleys B' B", the belts el ell,
the levers, and tension-rollers C¹C", of the springs m¹ m¹¹, connecting-
rods kk, the cranks g' and 9", forming an angle with each other, the shaft G,
handle H, the disc m having cam n and the spring o having recess o¹, substantially
as and for the purpose described.
,
8. In an engaging and disengaging gear for change-belts and -ropes, the combi-
nation, with two cranked shafts G G having their cranks gggg linked to
the levers carrying the expanding-rollers by means of connecting-rods kkkk
of the toothed wheels h¹ secured to the adjoining ends of the shafts G and G', the
laterally displaceable handle H adapted to engage with the toothed wheels h h by
means of a toothed disc p, and means for allowing the lateral displacement of the
handle only when the cranks on the side from which it is shifted are in such a
position as to maintain the corresponding belts or ropes disengaged, substantially as
shown in Fig. 8 of the accompanying drawings and described with reference thereto,
for the purpose set forth.
9. In an engaging and disengaging gear for change-belts and -ropes, the con-
struction of the toothed wheels provided with circular flanges q having
notches q', and with cams n adapted to snap into recesses o¹ of springs o, sub-
stantially as shown and described with reference to Figs. 9 & 10 in the accompanying
drawings, for the purpose specified.
Dated this 12th day of September 1892.
WILHELM MAYBACH,
By Geo. H. Rayner,
37, Chancery Lane, London, W.C., Agent for the Applicant.