U.S. patent number 3,653,347 [Application Number 05/055,314] was granted by the patent office on 1972-04-04 for automatic apparatus for sewing a seam of a predetermined configuration.
This patent grant is currently assigned to Necchi S.p.A.. Invention is credited to Nereo Bianchi.
United States Patent |
3,653,347 |
Bianchi |
April 4, 1972 |
AUTOMATIC APPARATUS FOR SEWING A SEAM OF A PREDETERMINED
CONFIGURATION
Abstract
A sewing machine including means for automatically sewing a seam
of a particular configuration. Fabric clamp means are guided past
the sewing needle by a guide means which simultaneously imparts a
rectilinear and a rotative motion to the clamp means.
Inventors: |
Bianchi; Nereo (Pavia,
IT) |
Assignee: |
Necchi S.p.A. (Pavia,
IT)
|
Family
ID: |
11235349 |
Appl.
No.: |
05/055,314 |
Filed: |
July 16, 1970 |
Foreign Application Priority Data
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Jul 20, 1969 [IT] |
|
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32418 A/69 |
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Current U.S.
Class: |
112/470.09 |
Current CPC
Class: |
D05B
23/00 (20130101); D05B 39/00 (20130101) |
Current International
Class: |
D05B
39/00 (20060101); D05B 23/00 (20060101); D05b
021/00 () |
Field of
Search: |
;112/2,121.12,121.11,121.15,102,204,205 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Boler; James R.
Claims
I claim:
1. Automatic apparatus for producing seams of a given profile
comprising: a sewing machine having a sewing needle, a needle plate
having an opening therein, a carriage slidable on rectilinear
guides, a fabric-holding clamp mounted on said carriage and
actuating means for same, means for guiding said clamp below the
needle of said sewing machine in accordance with a pre-determined
law of motion, characterized by the fact that the said actuating
means comprises a driving cylinder and piston which actuates said
carriage along said guides, said clamp having a groove of the shape
of the seam to be made, a boss fastened on the base of the sewing
machine and engaged with said groove at said opening of the needle
plate, means pivotally connecting said clamp at its one end to a
point of said carriage, the resultant motion of the clamp during
the operation of the apparatus being thus composed of a linear
translation and a rotation around a point thereof.
2. Apparatus according to claim 1, characterized by the fact that
the said actuating means comprises a hydropneumatic unit and a
movable shaft controlled thereby which is co-operatively engaged
with said carriage, composed of a pneumatic actuating cylinder for
driving said shaft and a pneumatic oil control cylinder for
adjustably controlling the speed of displacement of said shaft.
3. Apparatus according to claim 1, including means for regulating
the movements of said clamp which means comprise valves for
controlling the air flow to said pneumatic cylinder and opposing
parts carried along by the movement of the carriage only in the end
portions of its strokes and further including abutting suitable
feelers which actuate the valves at the end points of the darts,
said valves being arranged to effect a reversal of motion of the
clamp upon the commencement of the sewing of the dart and to effect
the reversal of the movement of the clamp and the stopping thereof
with a small delay, retarding members located at positions
corresponding to the end of the sewing of the dart for effecting
said delay, said valves also being adapted to determine the
direction of movement of the next dart in the direction opposite
the preceding direction.
Description
The present invention relates to an automatic apparatus for sewing
seams of a given profile, consisting of a sewing machine, a fabric
holding clamp and means for actuating same, means for guiding said
clamp below the needle of said sewing machine in accordance with a
predetermined law of motion and means for regulating and
controlling the successive phases of the entire operating
cycle.
In particular, said shaped stitches are of the type adapted to
obtain pleats on certain articles of clothing such as shirts to
impart to them esthetic and functional characteristics. These
pleats, which are commonly known as darts, are usually formed of
two consecutive linear segments slightly shifted in their direction
or continuous sections of small curvature and in all cases assume a
course close to linear.
The object of the present invention is to provide actuating means,
guide means and regulating and control means having characteristics
adapted to simplify the apparatus of the type indicated both in
cost and in operation.
In order to achieve this object, the technical problem to be solved
was to use a single simple means for actuating the fabric clamps
and to use in combination with same guide means for said clamp
which are just as simple in order to obtain the seam of the desired
shape.
The solution of the technical problem set forth above is
characterized by the fact that the said actuating means is composed
of a driving cylinder which by its shaft actuates a carriage which
is displaceable on linear guides and bears the fabric clamp which
has a groove of the shape of the seam to be made coupled to a boss
fastened on the base of the sewing machine at the hole of the
needle plate and is hinged at its one end to a point on said
carriage, the absolute movement of the clamp during the operation
of the apparatus being thus composed of a linear translation and a
rotation around a point thereon. In particular the said drive
cylinder is formed of a hydropneumatic unit composed of a pneumatic
actuating cylinder and an oil-control cylinder adapted to make the
speed of displacement of the said shaft connected to the
clamp-holding carriage uniform and adjustable.
Another characteristic of the invention, combined with the
particular systems of actuation and guidance of the fabric clamp,
relates to the carrying out of sewing operations to be effected on
the end portions of the darts. However, in order to form the sewing
of the darts, it is necessary to effect sections of double stitches
at the ends thereof. It is therefore necessary to obtain, at the
start and at the end of the sewing of a dart, namely at the end
thereof, the reversal of the movement of the clamp for a short
period of time necessary for the effecting of the fastening
stitches. Furthermore, for better utilization of the apparatus
which forms the object of the invention, there is not provided at
the end of the sewing an empty return of the clamp into the
starting position but the subsequent stitches start alternately
from opposite ends of the path of the carriage so that the stopping
point of one dart coincides with the starting point of the
next.
In order to obtain this, the means for the regulating and control
of the phases of the operating cycle comprise opposing elements
carried along in the movement of the carriage only in the end
portions of its stroke and interfering with corresponding feelers
which actuate valves at the end points of the darts, said valves
being arranged to effect the reversal of the motion of the clamp at
the start of the sewing of the darts and to effect the reversal of
the motion of the clamp and the stopping thereof with a small
adjustable delay at the end of the sewing of the dart and to
predetermine the direction of motion of the next dart in the
direction opposite the previous one.
In order to obtain the adjustable delay, retarders are provided
connected to said valves and composed of a base and of a pin which
is connected to the feeler actuating the valves and connected in
air-tight manner with a cavity provided in said base to penetrate
into same against the action of a return spring when the opposing
element actuates said feeler; the return time of the said pin
outside of said cavity and therefore the switching of the valve for
the control of the clamp is determined by the regulation of the
section of an opening which places the bottom of said cavity in
communication with the outside.
Other characteristics and advantages will become evident from the
description of the invention and from the accompanying drawings in
which:
FIG. 1 shows an overall view of the apparatus which is the object
of the invention;
FIG. 2 shows a detail of the apparatus of FIG. 1;
FIG. 3 shows the pneumatic diagram with the arrangement of the
various drive, regulating and control members, and
FIG. 4 shows schematically the form of sewing which can be carried
out with the apparatus of FIG. 1.
Referring to FIG. 1, 10 is a table on which there rests a sewing
machine 11 of which there can be noted the base 12, the upright 13
and the head 14. From this head 14 there emerges a needle bar 15
bearing a needle 16. In the lower part of the table 10, resting on
a profiled part 17, there is the footboard 18 which, via the rods
19 and 20, acts on two three-way valves 71 and 83 (FIG. 3) adapted
to control the actuation of the apparatus, as will be described
below.
On the top 21 of the table 10 there are fastened two plates 22 and
23 bearing the shafts 24, 25 and 26. The shaft 26 is supported by
two bushings 27 and 28 provided on the plates 22 and 23
respectively and bears at its two ends a part 29 adapted to
cooperate with the rollers 30 supported by the levers 31 of the two
three-way valves 32 and 33.
On the central portion of the shaft 26 there is secured a bar 34
having threaded holes 35 in which there are screwed blocks 36
adapted to regulate the length of the dart, as will be explained in
further detail below. Between the ends of the bar 34 and the
bushings 27 and 28 there are arranged the springs 37. On a bar 39
fastened on the top 21 of the table 10 there is pivoted at 40 a
U-shaped element 41 against which there rests a head 42 of a
hydropneumatic unit 43 composed of a pneumatic cylinder 44 and an
oil control cylinder 45 adapted to make the speed of displacement
of the shaft 46 of said hydropneumatic unit connected to a carriage
47 adjustable.
The regulation of the speed of displacement of the said shaft 46 is
provided by a flow regulator 120 (FIG. 3) placed between the heads
42 and 121 of the oil control cylinder 45. A bushing 48 is fastened
adjustably to one end of the carriage 47 by means of a tie 49. A
pin 50, which is free to rotate in the bushing 48, bears at the top
a block 51 to which there is fastened the lower plate 52 of the
fabric clamping clamp 53. The plate 52 bears two single-acting
pneumatic cylinders 54 and 55 the rods 56 of which are fastened to
a plate 57 forming the upper part of the clamp 53.
The carriage 47, during its translation controlled by the shaft 46,
moves along the shafts 24 and 25 which prevent the rotation thereof
and carries the clamp 53 along with it in its movement. A boss 58
placed on the base of the machine 12 at the hole of the needle
plate 22 connects with a groove 123 (FIG. 2) provided in the plate
52, reproducing the shape of the dart, and permitting transverse
oscillations of the clamp 53 which is free to rotate with its pin
50 in the bushing 48. In the vicinity of the end of the stroke of
the carriage 47, a finger 59 of the carriage 47 which can be seen
in FIG. 3 comes into contact with the block 36 and, overcoming the
strength of one of the springs 37, depending on the direction of
displacement, carries along with it the bar 34 and accordingly the
shaft 26 fastened to same in the direction towards the end of the
shaft 46 so that the part 29 comes into contact with the roller 30
of one of the valves 32 and 33, opening it. A ring 38 rigidly
connected with the shaft 26 permits the said shaft to rotate so as
to present to the finger 59 of the carriage 47 the surface of the
bar 34 with the blocks 36 placed at the distance corresponding to
the length of the darts which it is desired to obtain.
Referring to FIG. 4, the dart which is to be made is formed of two
linear sections of slight inclination with respect to a horizontal
line and has at its two ends sections of double stitches having the
purpose of stopping the seam in the initial section and in the
final section. Furthermore, it is advisable to start the sewing on
the inside of the dart since the end points thereof extend normally
to the edge of the fabric being worked and, due to inevitable lack
of precision in positioning, it may happen that the first stitches
are made outside the fabric if the sewing is started at the ends of
the dart. The sewing of the dart then takes place starting from the
point 1 and upon arriving at the point 2 there is caused a reversal
of the movement of the clamp, the path from 2 to 1 is reduced and
is continued to point 3. At this point there is another reversal of
the movement of the clamp to double the stitching from the point 3
to the point 4. The two seams are perfectly superimposed even
though, for ease in description, they have been shown separately in
FIG. 4.
At the start of the operation when the main compressed air conduit
is open, the compressed air passes from the feedline 60 through a
solenoid 61 (FIG. 3) into the air filter 62, the pressure gauge 63
and the lubricator 64. Through the conduit 65 the compressed air
arrives at a three-way valve 66 which is closed. Through the
conduit 68 the air which comes from the lubricator 64 via a
four-way valve 69 and the conduit 70 arrives at a two-way valve 71
which is opened when the footboard 18 is in the position of rest
shown in FIG. 3. Via the valve 71, a flow regulator 72, a fast
discharge valve 73, a plenum chamber 74 and a conduit 75, the air
arrives at a pilot 76 which opens the valve 66. The air of the
conduit 65, through the valve 66 which is now open and the conduit
67 arrives at the single-acting cylinders 54 and 55 which in this
way raise the plate 57 of the clamp 53. From the rapid discharge
valve 73, via the conduit 77, the four-way valve 78, the conduit 79
and the switching valve 80, the air arrives at a pilot 81 which
switches the four-way valve 82. The air which emerges from the
lubricator 64 via the conduit 124 arrives at a three-way valve 83
which is closed and via the branch 84 at the three-way valves 32
and 33 which are closed. Now the operator introduces between the
plates 52 and 57 of the clamp 53 the rear part of the shirt and
presses the board 18 into a position intermediate between the
valves 71 and 83. The valve 71 closes, interrupting the flow of air
in the conduits 77 and 75. The interruption of the flow of air into
the conduit 75 causes the closing of the valve 66 by the pilot 76
and the cylinders 54 and 55 discharge with the consequent closing
of the clamp 53 which clamps the fabric between the plates. By
further pressing the footboard 18 until the valve 83 is opened, the
air passing through the conduit 85 and the flow regulator 86
arrives at the pilot 87 which switches the valve 69. The air which
is present in the conduit 68 passes through the valve 69, the
conduit 88, the valve 82, the conduit 89, the rapid discharge valve
90 and arrives in the head 42 of the cylinder 44 causing the rod 46
to move in the direction of the arrow, it carrying along with it
the carriage 47 which bears the clamp 53 so as to obtain the sewing
from 1 to 2 (FIG. 4). At the same moment the air which passes
through the valve 69 through a conduit 91, a flow regulator 92 and
then through a rapid discharge valve 93, a plenum chamber 94, a
rapid discharge valve 95, arrives at the microswitch 96 which
controls the starting of the sewing cycle. The said microswitch 96
remains actuated for the entire duration of the cycle. During the
sewing from point 1 to point 2 shown in FIG. 4, the finger 59 comes
into contact with the block 36, axially displacing the bar 34 and
accordingly the part 29 which comes to interfere with the roller of
the valve 33, opening the latter.
The air of the valve 33, via the conduit 97 and the switch valve
98, arrives at the pilot 99 which switches the valve 82; the same
air which passes from the valve 33 via the conduit 100 arrives at
the pilot 101 which switches the valve 78 to prepare it for the
subsequent operations. With the switching of the valve 82, the air
of the conduit 88, passing through the conduit 102 and the rapid
discharge valve 103, enters into the head 104 of the cylinder 44,
displacing the rod 46 in the direction opposite that of the arrow A
so as to obtain the sewing from the point 2 to the point 3 of FIG.
4. During the sewing from point 2 to point 3, the bar 34, no longer
acted on by the finger 59, returns into its position of rest by
means of the return spring 37. In this way the roller 30 is no
longer in contact with the part 29 and the valve 33 closes,
discharging the conduits 97 and 100, the air of which, via the
conduit 114, the switching valve 109, the conduit 110 and the
needle valve 115, is discharged into the atmosphere, the pilot 125
not succeeding in switching the valve 69, since the pilot 87, when
the footboard 18 has been released, is still not discharged, being
connected to the flow regulator 86 which regulates the flow during
the discharge of the conduit 85. In the proximity of point 3 the
finger 59 of the carriage 57 engages the block 36 axially
displacing the bar 34 in such a manner that the part 29 comes into
contact with the roller 30 of the valve 32, opening it. The air
which is present in the conduit 34 via the valve 32, the conduit
105 and the switch valve 80 arrives at the pilot 81 and switches
the valve 82, while by means of a conduit 106 connected with the
conduit 105 the air arrives at the pilot 107 which switches the
valve 78. The air of the conduit 88, via the valve 82, the conduit
89 and the rapid discharge valve 90, enters the head 42 of the
cylinder 44, displacing the rod 46 in the direction indicated by
the arrow A until it arrives at the point 4, since the bar 34 not
being acted on any longer by the finger 59, returns into its
position of rest by means of the return spring 37. In this way the
roller 30 is no longer in contact with the part 29 and the valve 32
closes, placing the conduit 105 in discharge, the air of which
arrives via the conduit 108, the switching valve 109 and the
conduit 110 at the pilot 125 which switches the valve 69,
overcoming the resistance of the pilot 87. The switching of the
valve 69 causes the interruption of the flow of air in the conduits
88 and 91, in this way stopping the clamp 53 and stopping the
sewing machine. At the same time, the air, via the conduit 70 and
the valve 71 which is open, the flow regulator 72, the rapid
discharge valve 73, and the plenum chambers 74 and 112 actuates the
microswitch 113 which controls the thread cutter and via the
conduit 75 actuates the pilot 76 which opens the valve 66,
permitting the flow of air into the conduit 67 which actuates the
cylinders 54 and 55 which raise the plate 57 of the camp 53, thus
permitting the removal of the sewn fabric.
Via the conduit 77 and the valve 78, the machine is prepared for
the next sewing cycle at which the sewing will start at point 4 and
terminate at 1. The closing clamps of the paths 3-4 and 2-1 can be
made of variable length to satisfy given requirements in the
garment industry. For such purpose there are provided on the valves
32 and 33 two retarders 126 formed by a base 127, a pin 28 which
can slide against the action of a spring 129 within a cavity
provided on the upper surface of the base 127. The pin 128 has a
head 130 connected to the curved end of a shaft 131 connected to
the arm 31 of the valves 32 and 33. The cavity within which the pin
128 slides communicates with the outside through a hole, not shown,
the passage opening of which can be regulated by means of a screw
132. When the part 29, after having pressed against the roller 30,
at the end of the sewing of the end sections of the dart, releases
it, pulled back by the spring 37 into its dart, releases it, pulled
back by the spring 37 into its position of rest, the valve 32 or 33
which has been opened by the part 29 and has thus reversed the
direction of movement of the clamp must remain open for a certain
period of time in order to obtain the double closing seam, since
the closing of the said valve causes the stopping of the machine
and the stopping of the movement of the clamp. By regulating by
means of the screw 132 the opening which places the bottom of the
cavity of the base 127 in communication with the outside there is
obtained a faster or slower return of the pin 128 by the spring 129
and accordingly an adjustable time of rise of the arm 31 which
determines the desired retardation in the closing of the valve.
* * * * *