Year: 1886

page_text: I, OSCAR FREDRIK JONSSON, Electrician, of Stockholm, in the Kingdom of
Sweden, 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:-
The object of this invention is a friction coupling for rapidly revolving engine
shafts, particularly for the coupling of dynamo machines. On the annexed
drawing Figure 1 is a longitudinal section of the friction coupling, and Figure 2 a
side view of the same.
A is the shaft, on which the motor acts either directly or by means of gearings,
and B is the shaft, which is to be coupled with the former. On the shaft B a
pulley or wheel C is secured, the border of which D is bent perpendicularly against
the plan of the pulley. In the inside of this border a strip E of leather or another
suitable material is pressed into a groove turned out therein, and provided with
flutes or points. On the end of the shaft A a centre piece F is secured, which is
placed into the pulley C and is provided with four slots going radially out from
the centre, in which slots friction blocks may glide out and in. The outer ends of
the friction blocks are rounded on the same circular arc as the leather strip pressed
in and placed outside of the outer border of the centre piece. In order to guide
the blocks sideways, plates H are screwed fast over the slots, The blocks are
actuated by spiral springs I tending to press the same towards the circumference.
In each block is a link bar L pivoted on a pin K, the inner, towards the centre
directed end of which link bar is forked, thus clasping another link bar M on which
it is pivoted, this other link bar is going in the direction of the shaft A, and being
provided with a tail N projecting towards the pulley C, and entering into a hole
in the centre F. The other end of the link bar M is pivoted in a wing of a gliding
piece P which is gliding on the shaft A, and which piece may, by means of a lever,
be pushed back and to on the shaft, but cannot be turned round on the same.
The plate secured on the border of the pulley C has only for purpose to protect
the inner parts of the coupling, and to give the coupling a nice exterior
appearance.
The friction coupling works in the following manner. The centre piece F and
the coupling piece P partake always in the rotary motion of the shaft A. In order
that the blocks G may not by the centrifugal force be brought towards the circum-
D...All

page_text: ference, and get into contact with the pulley C, the tail N of the link bar M has
a shoulder R which is brought to encounter the edge of the hole O. The tail
is thus prevented from entering into the hole as well by the centrifugal force
acting upon the blocks as by the spiral springs I pressing outwards. These latter
ones may however be excluded, if the blocks are made sufficiently heavy. If the
parts have the position indicated above, and the coupling of the shaft B is wanted,
then the box P is conducted towards the centre F, whereby the shoulder R is
caused to glide over the edge of the hole O, so that the tail N can glide in to the
hole. The same is obviously effected simultaneously with all the four brake blocks.
These blocks are then free and may thus, as well by pushing the box inwards as
by the centrifugal force, be conducted outwards and pressed against the leathering
in the pulley C, and bringing this pulley and thereby the shaft in rotation.
the disengaging the box P is pushed in the opposite direction, until the shoulder R
of the tail N is brought outside of the edge of the hole, O, when the coupling is
locked. From this disposition it appears, that the greater the speed of rotation is,
the greater the pressure between the brake blocks and the pulley will be and the
surer the coupling is working. It also appears herefrom, that the lever, by which
the box is pushed back and to, needs not to be fixed in either position.
At
Having now particularly described and ascertained the nature of the said
Invention, and in what manner the same is to be performed, I declare that what
I claim is
A friction coupling, consisting of a centre (F) secured on the one end of the
shaft (A) and provided with slots, in which brake blocks (G) connected respectively
with a box (P) movable on the shaft, may by the agency of pivoted link bars
(L and M) and by means of the centrifugal force be pressed outwards against the
inner border of a pulley (b) secured on another shaft (B) and provided with a
leathering E, and prevented from coming into contact with the said pulley thereby
that a shoulder (R) on the tail (N) of the link bar (M), which tail enters into a
hole (O) in the centre (F), is stopped by the edge of the said hole.
Dated this 30th day of June 1886