Improved Mechanism for Converting Rotary into Reciprocating Motion.
Year: 1891

page_text: Date of Application, 22nd July, 1891-Accepted 2nd Apr., 1892
COMPLETE SPECIFICATION.
Improved Mechanism for Converting Rotary into Reciprocating
Motion.
I, WILLIAM WRIGHT VIRTUE, of 18 Bridge Street Sydney, in the Colony
of New South Wales, 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 :-
This invention of mechanism for converting rotary into reciprocating motion in
planes coincident with the axis of rotation, has for its object the reduction of
friction and of loose working and vibration; it is applicable to a great variety of
machines, including shearing and clipping machines and sewing machines, and is
of special utility where a vibratory motion is required at the end of a shaft line
with a minimum expenditure of space for containing the motion-converting
mechanism.
The essential principle of the invention consists in setting an overhung pin
or its mechanical equivalent excentrically upon a rotating shaft in such a way that
the centre-line of such overhung pin will if produced intersect the axis of vibration
of a lever bar, that axis being so placed as also to be met by the axis of rotation
of the shaft if the latter were produced.
Referring to the annexed sheet of explanatory drawings generally illustrative of
methods of application of the invention, Figures 1, 3, 4, 5, 6, 7, and 8 are sectional
elevations, and Figure 2 a plan of the mechanism shewn in Figure 1. The designs
shewn in Figures 1 and 3 differ only in the lengths of the forks or jaws on the
vibrating lever and in the length of the excentric pin. In Figure 4 an alternative
method of construction and setting of the excentric pin is shewn. Figures 5
and 6 illustrate methods of arrangement and construction of parts when the over-
hung excentric pia is used in combination with an intermediate lever or connecting
bar with couical-pendular motion. Figure 7 illustrates a construction wherein the
"motion block is forked. The method of arrangement and construction of the
parts when the centre of vibration is rearward of the end of the rotating shaft is
shewn in Figure 8.
:>
Figures 1, 2, 3, 4, and 7 illustrate the mechanism arranged to vibrate the bar in
a vertical plane; and Figures 5, 6, and 8 the mechanism arranged to vibrate the
bar in a horizontal plane.
The
In all the constructions shewn in these figures, the principle is the same.
several modifications differ from one another in constructive details only.
The same figures of reference indicate corresponding and similar parts in all the
figures.
Referring to Figures 1, 2, and 3, 1 is the bed, 2 shaft bearing, 3 brasses, 4 shaft,
5 screwed end of shaft, 6 balanced disc or crank integral with or secured to the
shaft 4 by screwing or otherwise, 7 overhung excentric pin or shaft cored out to
form an internal oil reservoir 14, 8 bush or bearing fitting truly about the pin or
shaft 7 and formed square exteriorly and exactly fitting the space between the
lever wings 11 of the vibrating piece 10, 9 screwed plug and nut, 12 fulcrum pin,
13 plummer block.
Referring to Figure 4, the solid square motion block 16 takes the place of the
overhung excentric pin or shaft 7 and the bushing 8, 17 is the shank of the motion
block 16, 18 back-nut, 19 internal oil reservoir.
Referring to Figure 5, 20 is the centre pin of the vibrating bar 21, 22 expanded
tail piece on same, 23 centre-pin of gyrating forked lever bar 24, 25 bored end of
bar 21, 26 oil chamber. The part 7 must be turned radially to the point of

page_text: •
intersection of the centres 20 and 23; and the shaft 4 is set so that its axis if
produced would cut that point, radial to which point also the part 7 is bored.
The construction shewn in Figure 6 is analogous to that last described. 27 is
the centre-pin of the vibrating bar 28, which bar is bifurcated rearward of the
centre, where it is provided with two bridge-pieces 29 which form bearings for the
pins 27, 30 are expanded tail pieces, 31 centre pin of the gyrating lever set at right
angles to the pins 27, 32 is the gyrating lever turned at the rear end 33 to fit a
hole in the part 6 bored radially to the point of intersection of the centres 27 and 31:
the shaft 4 must be set so that its axis if produced would also cut that point of
intersection.
The parts 6, 7, and 25 shewn in Figure 5 may be substituted for the parts 6
and 33 shewn in Figure 6, and rice-versa.
Figure 7 illustrates a modified construction of a motion block and a solid
vibrating bar; the motion block is forked so as to grasp the head (or the tail as
the case may be) of the vibrating bar; otherwise the construction is as shewn in
Figure 4. 34 is the centre-pin of the vibrating lever 35, which is provided with
an expanded head 36, 37 jaws or claws of motion block, 38 shank of same, 39 back-
nut, 40 oil chamber.
Referring to Figure 8 in which the fulcrum is shewn rearward of the point at.
which motion is applied, it will be seen that the overhung pin or shaft is struck
outwards, and not inwards as shewn in previous figures; otherwise the construction
is practically identical. 41 is the square bushing or bearing, 42 screwed plug
and nut, 43 centre-pin of the vibrating bar 44, 45 cheek piece of the bar 44.
It will be evident that the construction of the motion block shewn in Figure 7
may be adapted to the combination of parts shewn in Figure 8.
When a motion block or mechanism such as is shewn in Figures 1, 2, 3, 4, 7,
or 8 is used it is only essential that the axis of rotation and the axis of vibration
should be in the same plane, but when connecting bars such as are used in Figures ♬
or 6 are used it is necessary that the axis of rotation and the axis of the over-
hung pin should if produced always cut one another in the axis of vibration of the
lever.
In carrying out and applying my invention, I do not restrict myself to any
particular construction of mechanism so long as the essential principle is retained
of setting the rotating parts and the overhung pin in such a way that their axes if
produced would intersect the axis of vibration.
Having now particularly described and ascertained the nature of this invention
and in what manner the same is to be performed, I claim,―
1. The combination of a rotating disc or crank, a pin or shaft overhung there-
from excentrically, and a vibrating lever with cheeks or jaws, the parts being so
arranged that the axis of rotation and the axis of the overhung pin if produced
would intersect one another in the axis of vibration.
2. The combination of a rotating disc or crank, a forked vibrating lever, and a
connecting bar pivoted to the lever across its centre of vibration and turning at
the rear end in a hole in the disc or crank, the parts being so arranged that the
axis of rotation and the centre-line of the bored hole in the disc or crank would if
produced intersect one another in the axis of gyration.
3. The combination of a rotating disc or crank, a vibrating lever, and a forked
connecting rod pivoted to the lever across its centre of vibration and bored at its
rear end, and a pin overhung excentrically from the disc or crank moving in a hole
in the end of the connecting rod; the parts being so arranged that the axis of
rotation and the axis of the overhung pin if produced would intersect one another
in the axis of gyration..
4. The combination of a bar or lever capable of vibration, jaws or cheeks
thereon, and a pin overhung from a crank or disc and moving between such jaws or
cheeks, such pin being so set that its axis if produced would intersect the axis of

page_text: vibration of the bar or lever; the axes of rotation and vibration being in one
plane.
5.-The combination of a rotating disc or crank, a vibrating bar or lever having
its axis of vibration in the same plane as the axis of rotation, a pin overhung
excentrically on the disc or crank and set radially to the axis of vibration of the
bar or lever and adapted to operate between jaws or cheeks on such bar or lever.
6. The combination of the parts marked 6, 7, 10, 11, and 12, substantially as
described with reference to the drawings annexed.
7. The combination of the parts marked 6, 7, 8, 9 10, 11, and 12, substantially
as described with reference to the drawings annexed.
8. The combination of the parts marked 10, 11, 12, 15, 16, and 17, with or
without the part 18, substantially as described with reference to Figure 4 of the
drawings annexed.
9. The combination of the parts marked 6, 7, 20, 21, 23, 24, and 25, substantially
as described with reference to Figure 5 of the drawings annexed.
10. The combination of the parts marked 6, 27, 28, 29, 31, 32, and 33,
substantially as described with reference to Figure 6 of the drawings annexed.
11. The combination of the parts marked 6, 34, 35 37, and 38, with or
without the part 39, substantially as described with reference to Figure 7 of the
drawings.
12. The combination of the parts marked 6, 43, 44, and 45, with a pin over-
hung excentrically from the part 6 and turned radially to the point at which the
axes of rotation and vibration intersect, substantially as described with reference to
Figure 8 of the drawings annexed.
13. The combination of the parts marked 6, 41, 42 43, 44, and 45, and a pin
overhung excentrically from the part 6 and turned radially to the point at which
the axes of rotation and vibration intersect, substantially as described with reference
to Figure 8 of the drawings annexed.
Dated this 22nd day of July 1891
ABEL & IMRAY,
Agents for the Applicant.