U.S. patent application number 11/678701 was filed with the patent office on 2007-08-30 for sewing machine with sequin sewing device.
This patent application is currently assigned to TOKAI KOGYO MISHIN KABUSHIKI KAISHA. Invention is credited to Kenji SUZUKI.
Application Number | 20070199490 11/678701 |
Document ID | / |
Family ID | 38442816 |
Filed Date | 2007-08-30 |
United States Patent
Application |
20070199490 |
Kind Code |
A1 |
SUZUKI; Kenji |
August 30, 2007 |
SEWING MACHINE WITH SEQUIN SEWING DEVICE
Abstract
In a first shifting operation for shifting a sequin sewing
device from an operative position to an evacuated position or in a
second shifting operation for shifting the sequin sewing device
from the operative position to the evacuated position, descending
movement of a needle bar is inhibited by jumping the needle bar
with a sewing machine maintained in an operating condition. Also, a
jump code is inserted into embroidery data at a position where a
shift is to be made from sequin sewing to ordinary sewing or from
ordinary sewing to sequin sewing. Alternatively, the descending
movement of the needle bar may be inhibited by reducing a rotation
speed of the main machine shift with the machine maintained in the
operating condition.
Inventors: |
SUZUKI; Kenji; (Niwa-gun,
JP) |
Correspondence
Address: |
ROSSI, KIMMS & McDOWELL LLP.
P.O. BOX 826
ASHBURN
VA
20146-0826
US
|
Assignee: |
TOKAI KOGYO MISHIN KABUSHIKI
KAISHA
Kasugai-shi
JP
|
Family ID: |
38442816 |
Appl. No.: |
11/678701 |
Filed: |
February 26, 2007 |
Current U.S.
Class: |
112/98 |
Current CPC
Class: |
D05C 11/06 20130101;
D05C 7/08 20130101 |
Class at
Publication: |
112/98 |
International
Class: |
D05C 3/02 20060101
D05C003/02 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 27, 2006 |
JP |
2006-051157 |
Claims
1. A sewing machine comprising: a machine head including a needle
bar mechanism usable for both sequin sewing and ordinary sewing,
said needle bar mechanism having a vertically-movable needle bar
for sewing; a sequin sewing device provided in correspondence with
the needle bar mechanism and movable between an operative position
where said sequin sewing device can perform sequin sewing and an
evacuated position where said sewing device can not perform sequin
sewing; a needle bar control section that, in a first shifting
operation for shifting said sequin sewing device from the operative
position to the evacuated position or in a second shifting
operation for shifting said sequin sewing device from the evacuated
position to the operative position, inhibits or delays descending
movement of the needle bar of the needle bar mechanism while
maintaining said sewing machine in an operating condition; and a
movement mechanism that moves said sequin sewing device to the
evacuated position in said first shifting operation but moves said
sequin sewing device to the operative position in said second
shifting operation while said needle bar control section inhibits
or delays descending movement of the needle bar.
2. A sewing machine as claimed in claim 1 wherein, when an
embroidery pattern comprising a mixture of a sequin-sewn portion
and an ordinary embroidery portion is to be sewn, not only said
needle bar control section is caused to inhibit or delay the
descending movement of the needle bar but also said movement
mechanism is caused to move said sequin sewing device, in
correspondence with an embroidery pattern position where said first
shifting operation or said second shifting operation is to be
performed.
3. A sewing machine as claimed in claim 1 wherein said needle bar
control section inhibits the descending movement of the needle bar
by jumping the needle bar.
4. A sewing machine as claimed in claim 3 which further comprises:
an embroidery data supply section that supplies embroidery data of
an embroidery pattern comprising a mixture of a sequin-sewn portion
and an ordinary embroidery portion; and a data generation section
that determines, on the basis of supplied embroidery data, an
embroidery pattern position where said first shifting operation or
said second shifting operation is to be performed and inserts a
jump code, instructing a needle bar jump, into the embroidery data
in correspondence with the determined embroidery pattern position,
and wherein, in accordance with the jump code inserted in the
embroidery data, said needle bar control section and said movement
mechanism jump the needle bar and move said sequin sewing device
from the operative position to the evacuated position or from the
evacuated position to the operative position.
5. A sewing machine as claimed in claim 3 which performs embroidery
sewing on the basis of embroidery data of an embroidery pattern
comprising a mixture of a sequin-sewn portion and an ordinary
embroidery portion, and wherein the embroidery data have a jump
code, instructing a needle bar jump, inserted therein in advance in
correspondence with an embroidery pattern position where said first
shifting operation or said second shifting operation is to be
performed, and wherein, in accordance with the jump code inserted
in the embroidery data, said needle bar control section and said
movement mechanism jump the needle bar and move said sequin sewing
device from the operative position to the evacuated position or
from the evacuated position to the operative position.
6. A sewing machine as claimed in claim 1 wherein said needle bar
control section delays the descending movement of the needle bar by
reducing an operating speed of a main machine shaft.
7. A sewing machine as claimed in claim 6 which further comprises:
an embroidery data supply section that supplies embroidery data of
an embroidery pattern comprising a mixture of a sequin-sewn portion
and an ordinary embroidery portion; and a data generation section
that determines, on the basis of supplied embroidery data, an
embroidery pattern position where said first shifting operation or
said second shifting operation is to be performed and inserts a
main-machine-shaft speed reduction instruction, instructing
reduction of the operating speed of the main machine shaft, in the
embroidery data in correspondence with the determined embroidery
pattern position, and wherein, in accordance with the
main-machine-shaft speed reduction instruction inserted in the
embroidery data, said needle bar control section and said movement
mechanism reduces the operating speed of the main machine shaft and
move said sequin sewing device from the operative position to the
evacuated position or from the evacuated position to the operative
position.
8. A sewing machine as claimed in claim 6 which performs embroidery
sewing on the basis of embroidery data of an embroidery pattern
comprising a mixture of a sequin-sewn portion and an ordinary
embroidery portion, and wherein the embroidery data have a
main-machine-shaft speed reduction instruction inserted therein in
advance in correspondence with an embroidery pattern position where
said first shifting operation or said second shifting operation is
to be performed, and wherein, in accordance with the
main-machine-shaft speed reduction instruction inserted in the
embroidery data, said needle bar control section and said movement
mechanism jump the needle bar and move said sequin sewing device
from the operative position to the evacuated position or from the
evacuated position to the operative position.
Description
BACKGROUND OF THE INVENTION
[0001] The present invention relates generally to sewing machines
equipped with a sequin sewing device for sewing a sequin onto a
sewing workpiece, and more particularly an improved sewing machine
capable of moving a sequin sewing device between an operative
position where the sewing device can sew a sequin and an evacuated
position where the sewing device can not sew a sequin.
[0002] Heretofore, there have been known sewing machines which are
provided with a sequin sewing device to sew sequins (spangles) onto
a sewing workpiece. Japanese Patent Application Laid-open
Publication No. 2004-167097 (hereinafter referred to as "Patent
Literature 1") discloses a multi-head embroidery sewing machine
equipped with a sequin sewing device and capable of performing
sequin sewing and embroidery sewing in combination. According to
the disclosure of Patent Literature 1, the sequin sewing device is
provided on the left side surface of a needle bar case having a
plurality of needle bars supported therein, and the leftmost one of
the needle bars in the needle bar case is used as a sequin-sewing
needle bar (hereinafter "sequin needle bar"). The sequin sewing
device is vertically movable (i.e., ascendable and descendable)
relative to the needle bar case; namely, when a sequin is to be
sewn, the sequin sewing device is moved to a lowered position,
while, when a sequin is not to be sewn, the sequin sewing device is
evacuated upward to a raised position so as not to hinder ordinary
embroidery sewing.
[0003] The sequin sewing device includes a sequin feed mechanism
for feeding a strip of a multiplicity of continuously-connected
sequins (hereinafter also referred to as "continuous sequin strip")
at a predetermined pitch. More specifically, the continuous sequin
strip is played out or let out from a reel and then placed on the
upper surface of a support plate, after which the continuous sequin
strip is fed out at the predetermined pitch, corresponding to a
size of one sequin, through feeding operation of the sequin feed
mechanism. Sequin located at the leading end of the continuous
sequin strip, having been fed out by the sequin feed mechanism, is
sewn onto a sewing workpiece while being severed from the strip
through cooperation between a fixed knife secured to the support
plate and a movable blade rotatably provided on the support plate.
As the sequin needle bar is moved downward, the movable blade is
rotated by abutting against a needle clamp provided at the lower
end of the sequin needle bar, to thereby sever the leading sequin
from the strip in conjunction with the fixed knife.
[0004] When a sequin is to be sewn in the multi-head embroidery
sewing machine disclosed in Patent Literature 1, the sequin needle
bar is selected, and the sequin sewing device is moved downward to
the lowered position. Conversely, when embroidery sewing is to be
performed in the disclosed multi-head embroidery sewing machine,
other needle bars than the sequin needle bar are selected, and the
sequin sewing device is moved upward away from the lowered
position.
[0005] In many cases, sequin sewing and embroidery sewing are
performed on a sewing workpiece with a same color thread. In such
cases, it is more efficient to perform the sequin sewing and
embroidery sewing in a successive manner by means of the sequin
needle bar with the same colored thread without switching between
the needle bars. For such successive sequin sewing and embroidery
sewing operations, the disclosed multi-head embroidery sewing
machine is arranged to keep the sequin sewing device in the lowered
position throughout the successive sewing operations; this is for
the purpose of successively perform the sequin sewing and
embroidery sewing operations, without the sewing machine being
deactivated, to thereby reduce the necessary working time. As well
known in the art, when one needle bar used for a sewing operation
is to be switched to another (i.e., when so-called "thread color
change" is to be effected), not only the sewing machine is
deactivated, but also the thread of the needle bar having so far
been used for the sewing operation is severed. When the sequin
sewing device is to be vertically moved as well, the sewing machine
is deactivated, because there is a possibility of the movable
blade, moving together with the sequin sewing device, being damaged
if the blade abuts against the needle clamp of the sequin needle
bar. Thus, by performing ordinary embroidery sewing, which uses a
same colored thread as in sequin sewing, by means of the sequin
needle bar and keeping the sequin sewing device in the lowered
position as disclosed in Patent Literature 1, it is possible to
eliminate the needs for deactivating the sewing machine and
selecting a different needle bar from the sequin needle bar, so
that no time is required for such machine-deactivating and
needle-bar-selecting operations. As a result, the necessary working
time can be reduced. Of course, when ordinary embroidery sewing is
performed using the sequin needle bar, the sequin feed mechanism
does not feed out any sequin.
[0006] Although the sewing machine disclosed in Patent Literature 1
can reduce the necessary working time by performing ordinary
embroidery sewing, which uses with the same colored thread as in
sequin sewing, by means of the sequin needle bar with the sequin
sewing device kept in the lowered position, the needle clamp would
undesirably abut against the sequin needle bar as the sequin needle
bar descends because the embroidery sewing with the sequin needle
bar is performed with the sequin sewing device kept in the lowered
position. Namely, the movable blade would be unnecessarily hit by
the needle clamp and thus tends to be broken easily. In addition,
the unnecessary abutment between the needle clamp and the movable
blade would result in greater noise sound of the sewing
machine.
SUMMARY OF THE INVENTION
[0007] In view of the foregoing, it is an object of the present
invention to provide an improved sewing machine which, in
performing ordinary sewing with a sequin needle bar, can prevent
abutment between a needle clamp and a movable blade by moving a
sequin sewing device to an evacuated position, and which can
considerably reduce a necessary working time by allowing the sequin
sewing device to move between an operative position and the
evacuated position without the machine being deactivated.
[0008] In order to accomplish the above-mentioned object, the
present invention provides an improved sewing machine, which
comprises: a machine head including a needle bar mechanism usable
for both sequin sewing and ordinary sewing, said needle bar
mechanism having a vertically-movable needle bar for sewing; a
sequin sewing device provided in correspondence with the needle bar
mechanism and movable between an operative position where said
sequin sewing device can perform sequin sewing and an evacuated
position where said sewing device can not perform sequin sewing; a
needle bar control section that, in a first shifting operation for
shifting said sequin sewing device from the operative position to
the evacuated position or in a second shifting operation for
shifting said sequin sewing device from the evacuated position to
the operative position, inhibits or delays descending movement of
the needle bar of the needle bar mechanism while maintaining said
sewing machine in an operating condition; and a movement mechanism
that moves said sequin sewing device to the evacuated position in
said first shifting operation but moves said sequin sewing device
to the operative position in said second shifting operation while
said needle bar control section inhibits or delays descending
movement of the needle bar.
[0009] In the first shifting operation for shifting the sequin
sewing device from the operative position to the evacuated position
or in the second shifting operation for shifting the sequin sewing
device from the operative position to the evacuated position, the
descending movement of the needle bar of the needle mechanism is
inhibited or delayed with the sewing machine maintained in the
operating condition (e.g., rotation of a main machine shaft
maintained). Thus, the needle bar can be held in an upper position
away from the operative position, or the time for which the needle
bar is held in the upper position, can be increased, without the
sewing machine being deactivated, and the sequin sewing device can
be safely moved from the operative position to the evacuated
position or from the evacuated position to the operative position
while the needle bar is held in the upper position. Such
arrangements can not only prevent unwanted hitting or abutment
between the needle clamp and the movable blade, but also permits
the vertical movement of the sequin sewing device and thus achieves
a significant reduction of the necessary working time.
[0010] As an example, the needle bar control section is a needle
jump mechanism, which inhibits the descending movement of the
needle bar by placing the needle bar in a jump state.
[0011] As another example, the needle bar control section is a main
machine shaft speed control device (i.e., device for controlling
the operating speed of the main machine shaft), which inhibits the
descending movement of the needle bar by reducing the operating
speed of the main machine shaft.
[0012] According to a specific embodiment of the present invention,
when an embroidery pattern comprising a mixture of a sequin-sewn
portion and an ordinary embroidery portion is to be sewn, not only
the needle bar control section is caused to inhibit the descending
movement of the needle bar (i.e., jump the needle bar) or delays
the descending movement (reduces the operating speed of the main
machine shaft), but also the movement mechanism is caused to move
the sequin sewing device, in correspondence with an embroidery
pattern position where the first shifting operation is to be
performed.
[0013] For example, when ordinary embroidery sewing (i.e.,
operation for sewing an ordinary embroidery portion of the
embroidery pattern) is to be performed, after sequin sewing (i.e.,
operation for sewing a sequin-sewn portion of the embroidery
pattern), by means of the same needle bar as used in the sequin
sewing, the needle bar used in the sequin sewing is temporarily
placed in a jump state or the operating speed of the main machine
shaft is reduced, and then the sequin sewing device is moved from
the operative position to the evacuated position. After that, the
jump state of the needle bar is canceled or the operating speed of
the main machine shaft is brought back to the normal operating
speed, to thereby perform the ordinary embroidery sewing. Thus, the
movable blade attached to the sequin sewing device located in the
evacuated position is no longer hittable by the needle clamp of the
vertically-moved needle bar. Thus, during the ordinary embroidery
sewing with the same needle bar as in the sequin sewing, it is
possible to prevent the movable blade from being unnecessarily hit
by the needle clamp of the needle bar and thereby prevent the
movable blade from being easily broken. Also, with the
aforementioned arrangements, no hitting sound is produced between
the movable blade and the needle bar, so that the present invention
can prevent noise sound, produced by the sequin needle bar during
the ordinary embroidery sewing, from becoming great. Conversely,
when sequin sewing is to be performed, after ordinary embroidery
sewing, with the same needle bar as used in the ordinary embroidery
sewing, the descending movement of the needle bar used in the
ordinary embroidery sewing is inhibited (i.e., the needle bar is
jumped) or delayed (i.e., the operating speed of the main machine
shaft is reduced), and then the sequin sewing device is moved from
the evacuated position to the operative position. After that, the
descending movement inhibition (jump state) of the needle bar is
canceled or the operating speed of the main machine shaft is
brought back to the normal operating speed, to thereby perform the
sequin sewing. Namely, in each of the first and second shifting
operations, the vertical movement of the sequin sewing device is
effected with the needle bar placed in the jump state, and thus,
the positional shifting of the sequin sewing device is effected
without the operation of the sewing machine (rotation of the main
machine shaft) being stopped. As a result, the present invention
can significantly reduce a waste of the working time as compared to
the conventional counterpart in which the positional shifting of
the sequin sewing device is effected with the sewing machine
deactivated.
[0014] As an example, the sewing machine of the present invention
further comprises: an embroidery data supply section that supplies
embroidery data of an embroidery pattern comprising a mixture of a
sequin-sewn portion and an ordinary embroidery portion; and a data
generation section that determines, on the basis of supplied
embroidery data, an embroidery pattern position where the first
shifting operation or the second shifting operation is to be
performed and inserts a jump code instructing a needle bar jump (or
main-machine-shaft speed reduction instruction instructing
reduction of the operating speed of the main machine shaft) into
the embroidery data in correspondence with the determined
embroidery pattern position. In accordance with the jump code
inserted in the embroidery data, the needle bar control section and
the movement mechanism jump the needle bar (or reduce the operating
speed of the main machine shaft) and move the sequin sewing device
from the operative position to the evacuated position or from the
evacuated position to the operative position.
[0015] As another example, the embroidery data have a jump code
instructing a needle bar jump (or main-machine-shaft speed
reduction instruction instructing reduction of the operating speed
of the main machine shaft) inserted therein in advance in
correspondence with an embroidery pattern position where the first
shifting operation or the second shifting operation is to be
performed, and, in accordance with the jump code (or
main-machine-shaft speed reduction instruction) inserted in the
embroidery data, the needle bar control section and the movement
mechanism jump the needle bar (or reduce the operating speed of the
main machine shaft) and move the sequin sewing device from the
operative position to the evacuated position or from the evacuated
position to the operative position.
[0016] The following will describe embodiments of the present
invention, but it should be appreciated that the present invention
is not limited to the described embodiments and various
modifications of the invention are possible without departing from
the basic principles. The scope of the present invention is
therefore to be determined solely by the appended claims.
BRIEF DESCRIPTION OF DRAWINGS
[0017] FIG. 1 is a perspective view showing a general outer
appearance of a multi-head sewing machine in accordance with a
first embodiment of the present invention;
[0018] FIG. 2 is a left side view showing in enlarged scale a part
of an example sequin sewing device attached to one of the machine
heads in the embodiment of the present invention, which
particularly shows the sequin sewing device lowered to its
operative position;
[0019] FIG. 3 is a left side view of the sequin sewing device,
which shows the sequin sewing device raised to its evacuated
position;
[0020] FIG. 4 is a right side view showing in enlarged scale a part
of a sequin feed mechanism in the embodiment of the present
invention;
[0021] FIG. 5 is a block diagram showing an example control system
of the embroidery sewing machine according to the embodiment of the
present invention;
[0022] FIG. 6 is a flow chart showing an embodiment of processing
performed in the embodiment for automatically creating needle bar
jump data on the basis of embroidery data and then inserting the
created needle bar jump data in the embroidery data;
[0023] FIG. 7 is a diagram showing an embroidery pattern that
comprising a mixture of sequin-sewn portions and ordinary
embroidery portions; and
[0024] FIG. 8 is a schematic diagram showing example formats of
embroidery data corresponding to the embroidery pattern of FIG. 7,
of which (a) shows original embroidery data before insertion of
jump codes and (b) shows embroidery data after insertion of jump
codes.
DETAILED DESCRIPTION OF EMBODIMENTS
[0025] FIG. 1 shows a four-head embroidery sewing machine equipped
with four sewing machine heads and constructed in accordance with
an embodiment of the present invention. Needle bar cases 2 are
provided in corresponding relation to the sewing machine heads, and
a needle plate 30 is disposed under each of the needle bar cases 2.
Sequin sewing device 1 is attached to the left side and/or right
side of each of the needle bar cases 2; in the illustrated example,
the sequin sewing device 1 is attached to only the left side of the
associated needle bar case 2. Each of the needle bar cases 2
comprises a multi-needle structure, and, in the case where the
sequin sewing device 1 is attached to only the left side of the
associated needle bar case 2 as in the illustrated example, the
leftmost needle in the needle bar case 2 is used as a sequin-sewing
needle bar (i.e., sequin needle bar). As conventionally known in
the art, an embroidery frame 31 is driven in left-right (X) and
front-rear (Y) directions in accordance with predetermined sewing
data.
[0026] FIG. 2 is a left side view showing in enlarged scale one of
the sequin sewing devices 1 The sequin sewing device 1 includes a
mounting base 4, on which are supported a reel 5 having a
continuous sequin strip 3 wound thereon and a sequin feed mechanism
6. The mounting base 4 is mounted, via two connecting arms 8, on a
base 7 that is in turn fixed to the left side surface of the needle
bar case 2. Each of the connecting arms 8 is pivotably connected at
its opposite ends to the mounting base 4 and fixed base 7, and the
mounting base 4 is vertically movable (i.e., ascendable and
descendable) relative to the fixed base 7 (and hence the needle bar
case 2). Air cylinder 9 is provided on the mounting base 4 and
fixed to a bracket 10 that is pivotably connected to the mounting
base 4. Rod of the air cylinder 9 has a distal end fixed to a
bracket 11 that is pivotably connected to the fixed base 7. Through
activation of the air cylinder 9, the mounting base 4 vertically
moves relative to the fixed base 7, so that the entire sequin
sewing device 1 vertically moves between a lowered position (i.e.,
operative position) where the sewing device can sew a sequin and a
predetermined evacuated position (i.e., upper position shown in
FIG. 3) where the sewing device is evacuated above and away from
the lowered position.
[0027] FIG. 4 is a right side view showing in enlarged scale a part
of the sequin feed mechanism 6. The sequin feed mechanism 6 is
attached to a supporting plate 12 that is in turn mounted on a
lower portion of the mounting base 4. Support plate 13 for
supporting thereon sequins is horizontally attached to the lower
end of the supporting plate 12, and a continuous sequin strip 3 let
out from the reel 5 is led onto the upper surface of the support
plate 13. Pivot arm 15, pivotable by a motor 14 fixed to the
mounting base 4, is supported on the supporting plate 12. Feed
lever 16 is pivotably connected to a free end portion of the pivot
lever 15. The feed lever 16 is driven in a forward-rearward
direction, by means of the motor 14, so as to sequentially feed the
continuous sequin strip 3 at a predetermined pitch. Movable blade
17 is rotatably supported on a lower portion of the supporting
plate 12, and a fixed blade 18 is formed on an end edge portion of
the support plate 13 adjacent to the movable blade 17. The movable
blade 17 is normally retained, by means of a torsion spring 19, in
an evacuated position spaced upward from the fixed blade 18. The
movable blade 17 is pressed by a needle clamp 21 provided at the
lower end of a needle bar 20 as the needle bar 20 descends. As the
movable blade 17 is pressed by the needle clamp 21 of the
descending needle bar 20, the movable blade 17 pivots, against the
biasing force of the torsion spring 19, to cooperate with the fixed
blade 18 to sever the leading sequin from the fed continuous sequin
strip 3. As the needle clamp 21 ascends together with the needle
bar 20, the movable blade 17 returns to the evacuated position by
the biasing or restoring force of the torsion spring 19. The sequin
feed mechanism 6 is of the well-known type and has a construction
as disclosed in Patent Literature 1 discussed above, and thus a
detailed description of the sequin feed mechanism 6 is omitted
here.
[0028] FIG. 5 is a block diagram showing an example control system
of the embroidery sewing machine according to the instant
embodiment of the present invention. Various operations performed
by the embroidery sewing machine are controlled by a microcomputer
that includes a CPU (Central Processing Unit) 41, ROM (Read-Only
Memory) 42 and RAM (Random Access Memory) 43. Panel section 44
comprises switches and various other operators operable by a user
to make various settings, selections, instructions, etc., a display
and various other components. Storage section 45, which may
comprise a hard disk, removable storage medium, etc., stores
various control programs for carrying out the present invention,
various operation control programs, embroidery-pattern sewing data
corresponding to various embroidery patterns, etc. To a computer
bus 46 are connected, via interfaces (I/Fs), drivers (e.g., a
motor, solenoid, cylinder and the like) 47-51 for controllably
driving various mechanisms of the sewing machine. For simplicity,
FIG. 5 shows only the drivers 47-51.
[0029] Main machine shaft driver 47 includes a main machine shaft
motor. As well known in the art, a main machine shaft is rotated in
accordance with a machine operation instruction, in response to
which the needle bars selected in the individual machine heads are
driven vertically. The rotation of the main machine shaft is
stopped in accordance with a machine stop instruction. The
embroidery frame driver 48 includes X-axis and Y-axis driving
motors for driving the embroidery frame 31 in the X-axis and Y-axis
directions. As well known in the art, the embroidery frame 31 is
driven, in the X-axis and Y-axis directions, in accordance with a
stitch-by-stitch sewing pattern (sewing widths and directions)
corresponding to embroidery-pattern sewing data. The color change
driver 49 includes motors for sliding the needle bar cases 2 of the
individual machine heads. As also well known in the art, when a
colored thread change is to be effected, the needle bar cases 2 of
the individual machine heads are slid to select one of the needle
bars which has a desired colored thread set thereon. When sequin
sewing is to be performed, the needle bar 20 corresponding to the
sequin sewing device 1 is selected. The needle bar jump driver 50
includes solenoids etc, for placing the needle bars 20 of the
individual machine heads in a jump-sewing state. As also well known
in the art, if the needle bar 20 is jumped, the needle bar 20 is
held in a predetermined upper jump position and prevented from
being driven vertically, even when the main machine shaft is
rotating. The sequin driver 51 includes a driver (i.e., the
aforementioned motor 14) for driving the sequin feed mechanism 6 of
the sequin sewing device 1, and an elevating driver (i.e., the
aforementioned air cylinder 9). The driver (motor 14) for driving
the sequin feed mechanism 6 is controlled, by the CPU 14, in
correspondence with each sequin sewing stitch during a sequin
sewing operation. The elevating driver (air cylinder 9) is
controlled, by the CPU 14, to move the sequin sewing device 1 to
the lowered or operative position prior to the start of the sequin
sewing operation and move the sequin sewing device 1 to the
evacuated position after the end of the sequin sewing
operation.
[0030] In this specification, an operation for shifting the sequin
sewing device 1 from the operative position to the evacuated
position will be referred to as "first shifting operation", while
an operation for shifting the sequin sewing device 1 from the
evacuated position to the operative position will be referred to as
"second shifting operation". When the first shifting operation is
to be performed may be either automatically determined by the CPU
41 in accordance with a progression of the embroidery sewing
operation or automatically instructed at predetermined timing by
instruction data, inserted in embroidery data, in accordance with a
progression of the embroidery sewing operation, or may be
instructed at appropriate timing in response to operation by a
human operator of the sewing machine.
[0031] Further, during ascending/descending movement, via the
sequin driver 51, of the sequin sewing device 1, i.e. during the
first or second shifting operation, the CPU 41 performs needle bar
control for inhibiting or delaying the descending movement of the
needle bar while keeping the sewing machine in the operating
condition (i.e., without the sewing machine being deactivated).
First embodiment of the needle bar control comprises inhibiting the
descending movement of the needle bar by means of a needle bar jump
mechanism, as will be described in detail below.
[0032] According to the first embodiment of the needle bar control,
the CPU 41 and needle bar jump driver 50 function as a needle bar
control section, and the needle bar jump driver 50 is driven to
cause the needle bar 20 to jump under the control of the CPU 41. By
the jumping of the needle bar 20, undesired interference between
the ascending or descending sequin sewing device 1 and the needle
bar mechanism can be avoided even when the sequin sewing device 1
is caused to ascend or descend without the rotation of the main
machine shaft being stopped; particularly, it is possible to
prevent the needle clamp 21 from hitting the movable blade 17. Once
the sequin sewing device 1 is positioned in the predetermined
operative position or evacuated position after completion of the
descending/ascending movement, the jump control of the needle bar
20 is terminated, after which the needle bar 20 is driven
vertically in accordance with the rotation of the main machine
shaft. Further, when the ordinary embroidery sewing operation is to
be performed by means of the needle bar 20 corresponding to a
needle bar position where the sewing device 1 is disposed, it is
performed with the sequin sewing device 1 held in the upper
evacuated position; thus, the needle clamp 21 of the
vertically-driven (i.e., ascending and descending) needle bar 20
can be reliably prevented from hitting the movable blade 17 of the
sequin sewing device 1.
[0033] The aforementioned control for causing the needle bar 20 to
jump at the time of the first or second shifting operation is
advantageous particularly in a case where, during sewing of one
embroidery pattern, switching is performed as necessary between the
sequin sewing operation and the ordinary embroidery sewing
operation, using the same needle bar 20 (i.e., the same colored
thread) as used in the sequin sewing operation, with the sewing
machine maintained in the operating condition (i.e., without the
rotation of the main machine shaft being stopped). Namely, for
sewing of an embroidery pattern that comprises a mixture of
sequin-sewn portions and ordinary embroidery portions, i.e. that
requires a combination of sequin sewing and ordinary embroidery
sewing operations using a same colored thread, the human operator
can position the sequin sewing device 1 in the operative position
or in the evacuated position with the sewing machine maintained in
the operating state (i.e., without stopping the rotation of the
main machine shaft) by performing the first or second shifting
operation to vertically move the sequin sewing device 1 while
jumping the needle bar 20; in this way, it is possible to smoothly
perform the sequin sewing and ordinary embroidery sewing, using the
same thread needle bar 20, while alternately switching between the
sequin sewing and ordinary embroidery sewing operations. Further,
in such a case, throughout the ordinary embroidery sewing, the
needle clamp 21 of the vertically-driven (i.e., ascending and
descending) needle bar 20 can be reliably prevented from hitting
the movable blade 17 of the sequin sewing device 1, because the
sequin sewing device 1 is held in the upper evacuated position away
from the operative position.
[0034] Next, with reference to a flowchart of FIG. 6, a description
will be given about processing performed in the instant embodiment
for automatically creating needle bar jump data on the basis of
embroidery data and then inserting the created needle bar jump data
in the embroidery data. According to this embodiment, an embroidery
pattern to be sewn comprises a mixture of sequin-sewn portions and
ordinary embroidery portions i.e. that requires a combination of
sequin sewing and ordinary embroidery sewing in such a form that,
here and there in the embroidery pattern, a partial pattern change
occurs from sequin sewing to ordinary embroidery sewing or from
ordinary embroidery sewing to sequin sewing with a same colored
thread used. It is assumed here that original embroidery data
supplied from an embroidery pattern data memory (i.e., the
aforementioned storage section 45) are in the conventionally-known
format with no needle bar jump code set in correspondence with a
partial pattern change position of the embroidery pattern. Thus,
through the processing of FIG. 6, the instant embodiment
automatically creates jump data and inserts the created jump data
in the embroidery data at a necessary pattern change position.
[0035] By the human operator operating an operation start switch
after selecting a desired embroidery pattern, the sewing machine is
activated to start embroidery sewing, so that the processing of
FIG. 6 is started up. Let it be assumed that, in an original stage
at the start of the embroidery sewing, the sequin sewing device 1
is in the upper evacuated position. At step S1 of FIG. 6,
embroidery data groups, each having n stitches ("n" represents a
predetermined plural number), are sequentially pre-read from among
the embroidery data stored in the embroidery pattern data memory.
Namely, the stored embroidery data are sequentially pre-read per
n-stitch group; more specifically, the embroidery data group of 1st
to n-th stitches is first pre-read collectively, then the
embroidery data group of (n+1)-th to 2n-th stitches is pre-read
collectively, and so on. The number of pre-read stitches n need not
always be constant and may be varied as necessary. Each pre-read
embroidery data group of n stitches is stored into a working area
of the RAM 43 and then used in determination operations at steps to
be described below, and a "non-data jump code" etc. generated at
steps to be described below are inserted in the embroidery data
stored in the working area.
[0036] At step S2, a determination is made, on the basis of the
pre-read embroidery data group of n stitches, as to whether or not
the second shifting operation is to be performed for shifting the
sequin sewing device 1 from the evacuated position to the operative
position, i.e. whether the sequin sewing device should be lowered.
More specifically, it is determined, at step S2, whether the sequin
sewing device 1 is currently in the evacuated position and the
pre-read embroidery data group of n stitches contains a sequin code
(sequin feed-out instruction). The sequin code is an instruction
code for instructing feed-out of a sequin per predetermined stitch.
If the second shifting operation is to be performed as determined
at step S2, a further determination is made, at step S3, as to
which position of the embroidery data is an embroidery pattern
position where the second shifting operation is to be performed.
Then, in correspondence with the determined embroidery pattern
position, a "sequin lowering instruction" for instructing that the
second shifting operation be performed and a non-data jump code
(i.e., a code instructing only a needle bar jump with zero stitch
data) are generated, and the thus-generated non-data jump code is
inserted in the embroidery data for an appropriate number of
stitches. The number of stitches for which the non-data jump code
is to be inserted is set to correspond to a time required to lower
the sequin sewing device 1 from the evacuated position to the
operative position, and the number is varied in accordance with the
number of rotations of the main machine shaft. For example, if the
non-data jump code is inserted for three stitches, the embroidery
frame 31 is kept unmoved (i.e., kept in the jump state) at sewing
timing of these stitches (because of the zero stitch data), during
which time the sequin sewing device 1 is lowered from the evacuated
position to the operative position. For example, at step S3, the
i-th stitch with no sequin code set therefor and (i+1)-th stitch
with a sequin code set therefor are identified, and a boundary
between the i-th stitch and the 1+i)-th stitch is determined to be
an embroidery pattern position where the second shifting operation
is to be performed. Then, a non-data jump code for an appropriate
number of stitches is inserted in the embroidery data following the
i-th stitch, and a sequin lowering instruction is inserted in
correspondence with the first one of the appropriate number of
stitches.
[0037] At next step S4, a determination is made, on the basis of
the pre-read embroidery data group of n stitches, as to whether or
not the first shifting operation is to be performed for shifting
the sequin sewing device 1 from the operative position to the
evacuated position. In order to avoid waste of the working time
resulting from frequent ascending and descending movement of the
sequin sewing device, the sequin sewing device 1 in the instant
embodiment is moved upward from the operative position to the
evacuated position only after it has been confirmed that more than
a predetermined number of stitches with no sequin code have
occurred in succession, rather than being moved upward immediately
upon detection of a stitch with no sequin code occurring in the
embroidery data. Therefore, in the instant embodiment, it is
determined, at step S4, that the first shifting operation should be
performed, i.e. the sequin sewing device should be caused to ascend
or raised (namely, YES determination is made at step S4), only when
absence of the sequin code has been detected in succession for a
predetermined number of stitches (e.g., 100 stitches) following
detection of a stitch with no sequin code. Such a "predetermined
number of stitches" may be variably set as desired by the human
operator of the sewing machine. Let it be assumed here that, in the
determination at step S4, whether or not the sequin code has not
appeared (i.e., has not been detected) in succession for a
predetermined number of stitches (e.g., 100 stitches) is determined
regarding not only the current pre-read embroidery data of n
stitches but also the last pre-read embroidery data of n stitches.
All through the predetermined number of stitches (e.g., 100
stitches), the sequin sewing device 1 is maintained in the lowered
position and thus the movable blade 17 is hit by the needle clamp
21 although the ordinary embroidery sewing is being performed;
however, the instant embodiment accepts the hitting by the needle
clamp 21 as inevitable, in order to give priority to minimization
of the waste of the working time. With the sequin sewing device 1
maintained in the lowered position all through the predetermined
number of stitches, the ordinary embroidery sewing is carried out
with no sequin feed-out, because there is no sequin code recorded
for these stitches. Needless to say, the sequin sewing device 1 may
be raised immediately upon detection of when a stitch with no
sequin code, without a leeway being set for the ascending movement
of the sequin sewing device 1 as noted above; in this case, it is
possible to completely prevent the movable blade 17 from being hit
by the needle clamp 21.
[0038] With a YES determination at step S4, a "sequin raising
instruction" for instructing that the first shifting operation be
performed is generated, at step S5, in correspondence with an
embroidery pattern position having been determined to be a position
where the first shifting operation is to be performed (i.e., an
embroidery pattern position the predetermined number of stitches
after the detection that the stitch with no sequin code). Also, at
step S5, a non-data jump code is generated and inserted in the
embroidery data for an appropriate number of stitches, in a manner
similar to the above-described. As also stated above, the number of
stitches for which the non-data jump code is to be inserted is set
to correspond to a time required to raise the sequin sewing device
1 from the operative position to the evacuated position.
[0039] At following step S6, a determination is made as to whether
or not an "operation routine" of the sewing machine has already
been started. If the "operation routine" has not yet been started
as determined at step S6, the operation routine is started at step
S7. At the "operation routine" step S7, the main machine shaft is
rotated, and the embroidery data stored in the working area of the
RAM 43 are sequentially read out, stitch by stitch, so that
embroidery sewing (sequin sewing or ordinary embroidery sewing) is
performed in accordance with the read-out embroidery data. If, on
the other hand, the "operation routine" has already been started as
determined at step S6, a determination is made, at step S8, as to
whether or not an embroidery data group of next n stitches should
be read. For example, once a quantity of unprocessed embroidery
data in the working area reaches a predetermined number of stitches
as the embroidery sewing progresses, a pre-read instruction is
generated by the "operation routine" step S7. When generation of
such a pre-read instruction has been detected, the processing
returns from step S8 to step S1 in order to pre-read the embroidery
data of the next n stitches. Thus, the aforementioned operations of
steps S2-S5 are repeated to generate a "sequin lowering
instruction" or "sequin raising instruction" and "non-data jump
code" and insert the thus-generated instruction and jump code into
the embroidery data of the next n stitches in question. Once the
main machine shaft is rotated at the start of the embroidering, the
operation of the sewing machine is performed in a continuous manner
so that the "operation routine" step S7 is carried out
continuously, unless a machine stop instruction is given. When a
colored thread change is to be effected, for example, the sewing
machine is deactivated temporarily even during the course of
embroidery pattern sewing, so as to effect cutting of the sewing
thread so far used and selection of and switching to the needle bar
corresponding to a new colored thread. On the other hand, when a
shift is to be made from the sequin sewing to the ordinary
embroidery sewing, or vice versa, no machine stop instruction is
generated and thus the operation of the sewing machine is continued
without being stopped, unless a colored thread change is
instructed. Thus, in the case where the embroidery data to be
supplied from the embroidery pattern data memory (storage section
45) are in the conventional format, and when a shift is to be made
from the sequin sewing to the ordinary embroidery sewing, or vice
versa, with no colored thread change, any machine stop instruction
inserted in the embroidery data is deleted as a jump code is
inserted through the operation of step S3 or S5. Further, when the
embroidery pattern sewing is to be ended, an end instruction is
generated, in place of a pre-read instruction, by the "operation
routine" step S7, in response to which the processing of FIG. 6 is
brought to an end.
[0040] The following paragraphs describe a specific example of the
sewing operation performed in the instant embodiment, in relation
to a case where an embroidery pattern to be sewn is of a type
comprising a mixture of sequin-sewn portions and ordinary
embroidery portions, i.e. requiring a combination of sequin sewing
and ordinary embroidery sewing as illustrated in FIG. 7. In FIG. 7,
A1-A3 indicate ordinary embroidery sewing (ordinary embroidery
portions), and B1 and B2 indicate sequin sewing (sequin-sewn
portions). Let it be assumed here that the ordinary embroidery
sewing A1-A3 and the sequin sewing B1 and B2 are performed with a
same colored thread and in the order of "embroidery sewing
A1.fwdarw.sequin sewing B1.fwdarw.embroidery sewing
A2.fwdarw.sequin sewing B2.fwdarw.embroidery sewing A3. Also assume
that each of the ordinary embroidery sewing A1 and A3 requires 100
stitches or more while the ordinary embroidery sewing A2 requires
less than 100 stitches.
[0041] In a case where embroidery data of an embroidery pattern as
illustrated in FIG. 7 are stored in an external memory, the stored
embroidery data are read out from the external memory into the
sewing machine and then stored into the embroidery pattern data
memory (storage section 45) that is, for example, in the form of a
hard disk. Then, for how many switches a non-data jump code is to
be generated at the time of raising/lowering the sequin sewing
device 1 is set, and at which one of successive stitches of the
ordinary embroidery sewing following the sequin sewing the sequin
sewing device 1 is to be evacuated upward, i.e. how many stitches
of the ordinary embroidery sewing have to be counted before the
sequin sewing device 1 is evacuated upward (namely, the
predetermined number of stitches noted above in relation to step S4
of FIG. 6) is set. Here, it is assumed that a non-data jump code is
generated for three stitches and the sequin sewing device 1 is
evacuated when 100 stitches or over of the ordinary embroidery
sewing have occurred following the sequin sewing. As noted above,
these numbers of stitches may be preset or variably set by the
human operator. Further, the number of stitches for which a
non-data jump code is to be generated may be determined in
accordance with the current number of rotations of the sewing
machine, or may be set individually or separately for the upward
evacuating movement and for the lowering movement.
[0042] Once sewing is started by activation of the sewing machine,
a desired sequin needle bar is selected in accordance with colored
thread data. At an initial stage of the sewing, the sequin sewing
device 1 is still kept in the upper evacuated position because no
sequin code has been detected yet from the pre-read embroidery
data. Through execution of the operation routine S7 of FIG. 6, the
ordinary embroidery sewing A1 is performed using the sequin needle
bar. Then, once the data of the sequin sewing B1 are pre-read in
accordance with a progression of the ordinary embroidery sewing A1,
not only a non-data jump code is generated and inserted, along with
a "sequin lowering instruction", in a predetermined embroidery
pattern position, where a stitch with no sequin code set therefor
switches to a stitch with a sequin code set therefor, for three
stitches immediately before the stitch with a sequin code. For
reference purposes, a format of original embroidery data is
schematically shown in (a) of FIG. 8, and a format of embroidery
data having the "sequin lowering instruction", "sequin raising
instruction" and "non-data jump code" inserted therein is
schematically shown in (b) of FIG. 8. Thus, when the ordinary
embroidery sewing A1 has been completed through the execution of
the operation routine step S7 of FIG. 6, the sequin needle bar is
placed in the jump state for three stitches and the sequin sewing
device 1 is lowered to the operative position while the sequin
needle bar is placed in the jump state, in accordance with the
"sequin lowering instruction" and "non-data jump code" inserted as
data for the next stitch; throughout such a period, the rotation of
the main machine shaft is maintained.
[0043] Then, once the sewing has progressed to a stitch with a
"sequin code" following the sewing of the stitches of the "non-data
jump code" through the execution of the operation routine step S7
of FIG. 6, the jump state of the sequin needle bar is canceled so
that sewing responsive to the vertical movement of the needle bar
is permitted, the sequin feed mechanism 6 is activated, in
accordance with the "sequin codes", to feed a continuous sequin
strip 3, and thus, the sequin sewing B1 is performed. Then, once
the data of the ordinary embroidery sewing A2 are pre-read in
accordance with a progression of the sequin sewing B1, a
determination is made, at step S4 of FIG. 6 and in an embroidery
pattern position where a shift is made to the ordinary embroidery
sewing, as to whether the first shifting operation is to be
performed for shifting the sequin sewing device 1 from the
operative position to the evacuated position. More specifically, at
step S4 of FIG. 6, a determination is made as to whether or not the
ordinary embroidery sewing A2 has lasted for 100 stitches or more
following the sequin sewing B1. In the illustrated example, where
the ordinary embroidery sewing A2 is less than 100 stitches, a NO
determination is made at step S4, so that the operation of step S5
of FIG. 6 is skipped; thus, the sequin sewing device 1 is not
evacuated and no non-data jump code is generated either. In this
case, the sequin sewing device 1 is still kept in the lowered
position when the ordinary embroidery sewing A2 is to be performed,
through the operation routine, following the sequin sewing B1;
however, because of absence of the "sequin code", the continuous
sequin strip 3 is not fed so that the ordinary embroidery sewing A2
can be performed safely.
[0044] Then, once the data of the sequin sewing B2 are pre-read in
accordance with a progression of the ordinary embroidery sewing A2,
a determination is made, at step S2 of FIG. 6 and on the basis of
recognition of a sequin code, as to whether the second shifting
operation is to be performed for shifting the sequin sewing device
1 from the evacuated position to the operative position. Because
the sequin sewing device 1 is still kept in the lowered position at
this stage, there is no need to perform the second shifting
operation, and thus, a NO determination is made at step S2. Thus,
generation and insertion of a "sequin lowering instruction" and
"non-data jump code" is not executed at step S3 of FIG. 6. Upon
completion of the ordinary embroidery sewing A2 through the
execution of the operation routine, a shift is made to the sequin
sewing B2. Because the sequin sewing device 1 is still kept in the
lowered position at this stage and because "sequin codes" are
included in the stitch data, the sequin feed mechanism 6 is
operated, in accordance with the sequin codes, to feed the
continuous sequin strip 3, so that the sequin sewing B2 is
performed.
[0045] Then, once the data of the ordinary embroidery sewing A3 are
pre-read in accordance with a progression of the sequin sewing B2,
a determination is made, at step S4 of FIG. 6 and in an embroidery
pattern position where a shift is made to the ordinary embroidery
sewing, as to whether the first shifting operation is to be
performed for shifting the sequin sewing device 1 from the
operative position to the evacuated position. Because, in this
case, the ordinary embroidery sewing A3 lasts for 100 stitches or
more, a YES determination is made at step S4 of FIG. 6, so that the
processing goes to step S5. At step S5, not only a "non-data jump
code" for three stitches is generated and inserted, along with a
"sequin raising instruction", between the last stitch of the sequin
sewing B2 and the first stitch of the ordinary embroidery sewing
A3. Upon completion of the sequin sewing B2 through the execution
of the operation routine, the feeding of the continuous sequin
strip 3 is stopped and the sequin needle bar is placed in the jump
state for three stitches, during which time the sequin sewing
device 1 is moved upward from the operative position to the
evacuated position. Throughout such a period, the rotation of the
main machine shaft is maintained. Immediately after that, the jump
state of the sequin needle bar is canceled, so that the ordinary
embroidery sewing A3 is performed on the basis of the embroidery
data of the embroidery sewing A3. At this stage, the sequin sewing
device 1 is still kept in the evacuated position, and thus, the
movable blade 17 of the sequin sewing device 1 is not hit by the
needle clamp 21 of the vertically-moving needle bar 20. After
completion of the ordinary embroidery sewing A3, the sewing machine
is deactivated.
[0046] As described above, the instant embodiment is arranged in
such a manner that, when embroidery sewing is to be performed using
the sequin needle bar before or after sequin sewing, the
raising/lowering of the sequin sewing device 1 is effected, with
the sequin needle bar placed in the jump state, without the sewing
machine being deactivated. Thus, the instant embodiment can
reliably prevent the movable blade 17 from being unnecessarily hit
by the needle clamp 21 and thereby prevent the movable blade 17
from being easily broken. Also, because no hitting sound is
produced between the movable blade 17 and the needle bar 21, the
instant embodiment can prevent noise sound, produced by the sequin
needle bar during embroidering, from becoming great. Further,
because the raising/lowering of the sequin sewing device 1 is
effected with the sequin needle bar placed in the jump state, the
embodiment can significantly reduce a waste of the working time as
compared to the conventional counterpart in which the
raising/lowering of the sequin sewing device is effected with the
sewing machine deactivated. Furthermore, in a case where the number
of embroidering stitches is relatively small and thus the operating
efficiency may be lowered if the sequin sewing device is raised and
lowered, the raising/lowering of the sequin sewing device may be
omitted.
[0047] Next, a description will be given a second embodiment of the
needle bar control, where, at the time of the aforementioned first
shifting operation or second shifting operation, control is
performed for delaying the descending movement of the needle bar
with the sewing machine maintained in the operating condition. In
the second embodiment, the CPU 41 functions as a needle bar control
section, which delays the descending movement of the needle bar 20
by reducing the moving speed of the needle bar 20. Because,
normally, the needle bar 20 is driven vertically in interlocked
relation to the rotation of the main machine shaft, the speed
reduction of the needle bar 20 can be achieved by reducing the
rotation speed of the main machine shaft. Raising/lowering of the
sequin sewing device 1, similar to the aforementioned
raising/lowering (i.e., the aforementioned first shifting operation
or second shifting operation), is effected while the descending
movement of the needle bar 20 is being delayed.
[0048] In order to carry out the second embodiment, it is only
necessary to insert a "main-machine-shaft speed reduction
instruction" in embroidery data, in place of the "non-data jump
code" that is inserted in the first embodiment for instructing the
raising/lowering of the sequin sewing device 1 (i.e., the
aforementioned first shifting operation or second shifting
operation). Thus, once the "main-machine-shaft speed reduction
instruction" is given during an embroidery sewing operation, the
rotation speed of the main machine shaft is reduced in response to
the main-machine-shaft speed reduction instruction, and thus, the
vertically-driven speed of the needle bar 20 is reduced in a
predetermined portion of its stroke so that the descending
movement, from a raised position, of the needle bar 20 is delayed.
Therefore, the raising/lowering of the sequin sewing device 1
(i.e., the aforementioned first shifting operation or second
shifting operation) can be effected during a leeway period before
the start of the descending movement, from the raised position, of
the needle bar 20. Note that the number of rotations of the main
machine shaft at the time of the speed reduction may be preset or
variably set as desired by the human operator of the sewing
machine.
[0049] Therefore, in this second embodiment too, when embroidery
sewing is to be performed using the sequin needle bar before or
after sequin sewing, the raising/lowering of the sequin sewing
device 1 can be effected without the sewing machine being
deactivated. Further, because the descending movement of the needle
bar is delayed, the second embodiment can prevent the movable blade
17 from being unnecessarily hit by the needle clamp 21 and thereby
prevent the movable blade 17 from being easily broken. Also,
because no hitting sound is produced between the movable blade 17
and the needle bar 21, the second embodiment can prevent noise
sound, produced by the sequin needle bar during embroidering, from
becoming great. Further, the second embodiment can significantly
reduce a waste of the working time as compared to the conventional
counterpart in which the raising/lowering of the sequin sewing
device is effected with the sewing machine deactivated.
[0050] As described above, each of the embodiments is arranged in
such a manner that embroidery data are pre-read per predetermined
number of stitches and the "non-data jump code" or
"main-machine-shaft speed reduction instruction", intended to shift
the sequin sewing device 1 vertically between the evacuated
position and the operative position, is generated and inserted
substantially concurrently with (or slightly ahead of the sewing
operation. However, the present invention is not so limited and may
be arranged in such a manner that, when embroidery data of a
desired embroidery pattern have been read from an external memory
to the sewing machine before the operation of the sewing machine is
started, all of the embroidery data of the embroidery pattern are
checked, then all "sequin lowering instructions", "sequin raising
instructions" and "non-data jump codes" (or "main-machine-shaft
speed reduction instructions") to be inserted are generated and
inserted into the embroidery data and then the operation of the
sewing machine is started. In another alternative, "sequin lowering
instructions", "sequin raising instructions" and "non-data jump
codes" (or "main-machine-shaft speed reduction instructions") may
be inserted in advance in embroidery data of a desired embroidery
pattern, and such embroidery data having the jump codes (or
"main-machine-shaft speed reduction instructions") inserted therein
may be read from an external memory or the like into the sewing
machine.
[0051] Further, arrangements may be made such that the sequin
sewing device 1 can be held in an intermediate position
(hereinafter referred to as "lower evacuated position") between the
operative position and the aforementioned evacuated position
(hereinafter referred to as "upper evacuated position"). If the
sequin sewing device 1 is caused to vertically move only between
the operative position and the lower evacuated position at the time
of switching between sequin sewing and ordinary embroidery sewing
using the sequin needle bar, it is possible to reduce the time
required for the vertical movement of the sequin sewing device 1.
In such a case, it is better to evacuate the sequin sewing device 1
to the upper evacuated position when the sewing machine has been
deactivated. Namely, the evacuated position used may be any one of
two or more predetermined evacuated positions, rather than just
one, as long as it is a position where the sequin sewing device 1
can not perform sequin sewing (i.e., where the movable blade 17 is
not hit by the needle clamp 21).
[0052] The drive means for vertically moving the sequin sewing
device 1 is not limited to the air cylinder 9 and may be an
electric motor or other actuator.
[0053] Further, whereas the embodiments of the present invention
have been described above in relation to the multi-head,
multi-needle sewing machine equipped with the sequin sewing device
1, the present invention may be applied to sewing machines of
various other types equipped with a sequin sewing device.
* * * * *