Technical Field
[0001] The present invention relates to embroidery sewing machines for performing sewing
on cylindrically-shaped embroidering workpieces, such as bodies of sweaters and T-shirts.
Background Art
[0002] In embroidering the body of a T-shirt, for example, it is necessary to position a
cylindrical rotary hook bed, having a rotary hook provided therein, inside the cylindrically-shaped
body set on an embroidery frame. One example of such a construction is disclosed in
Japanese Utility Model Publication No. HEI-1-11751. When a shirt is set on the embroidery frame with the shirt's front body positioned
over the upper surface of the rotary hook bed, as clear from the No. HEI-1-11751 publication,
the shirt's back body hangs from the periphery of the embroidery frame down the rotary
hook bed. Further, with the fashion individualization trends in recent years, there
has been an increasing demand for so-called "combination embroideries" in the embroidery
industry as well. Examples of the combination embroideries include a combination of
an ordinary multi-color embroidery and a decorative embroidery made by sewing of a
tape, string or other material, and an operation for making such combination embroideries
is performed today by a dedicated combination-embroidery sewing machine provided with
two different types of machine heads intended for multi-color embroidering and decorative
embroidering.
[0003] Although combination embroidery can be performed by a single embroidery sewing machine
as long as it is dedicated to combination-embroidery, there has so far been no combination-embroidery
sewing machine capable of embroidering a cylindrically-shaped embroidering workpiece,
for the following reasons. Namely, in order to embroider a cylindrically-shaped embroidering
workpiece, it is necessary to position the rotary hook bed inside the cylindrically-shaped
embroidering workpiece, as noted above. Thus, in order to embroider such a cylindrically-shaped
embroidering workpiece using two types of machine heads, it is necessary to position
two cylindrical rotary hook beds, corresponding to the two machine heads, inside the
cylindrically-shaped embroidering workpiece. Therefore, there would be encountered
not only the inconvenience that kinds of embroidering workpieces that can be embroidered
tend to be limited, but also the inconvenience that, even with an embroiderable embroidering
workpiece, a sufficient embroidering area can not be secured unless the hanging-down
portion of the workpiece has a sufficient margin. One possible approach for avoiding
the above inconveniences is to position only one of the hook bed, corresponding to
the machine head to be next used for embroidering, inside the embroidering workpiece;
however, when the other machine head is to be next used for embroidering after completion
of embroidery by the one machine head, it is necessary to deactivate the embroidery
sewing machine to detach and re-attach the embroidery frame in order to switch the
rotary hook bed that is to be positioned inside the embroidering workpiece, which
would inevitably require extra labor and time. In addition, there are possibilities
of part of the embroidering workpiece, hanging down the rotary hook bed, interfering
with the rotary hook bed and being stained or impaired. For the foregoing reasons,
none of the conventionally-known embroidery sewing machines can not perform combination
embroidery by itself.
Disclosure of the Invention
[0004] In view of the foregoing, it is an object of the present invention to provide an
embroidery sewing machine which can smoothly perform, without any problem, combination
embroidery on a cylindrically-shaped embroidering workpiece using a plurality of types
of machine heads.
[0005] In order to accomplish the above-mentioned object, the present invention provides
an improved embroidery sewing machine for a cylindrically-shaped embroidering workpiece,
which comprises: a head group comprising two or more machine heads disposed in proximity
to each other so that each of the machine heads can perform embroidery sewing on an
embroidering area of an embroidery frame on which the cylindrically-shaped embroidering
workpiece is set, at least one of the two or more machine heads being a multi-needle
machine head having a plurality of needles; a color change mechanism for selectively
positioning a desired one of the needles at a predetermined operating position in
the multi-needle machine head; a rotary hook bed provided for each of the head group
for shared use between the machine heads in the head group and corresponding to one
embroidering workpiece; and a horizontal movement mechanism for disposing individual
ones of the machine heads and the color change mechanism for horizontal movement relative
to the rotary hook beds and horizontally moving the individual machine heads and the
color change mechanism together to place any one of the machine heads in each of the
head groups in positional correspondence to the rotary hook bed.
[0006] By selectively placing either one of the plurality of machine heads in each of the
head groups in positional correspondence to one rotary hook bed in the aforementioned
manner, the present invention can perform different types of embroidery or sewing
with the respective machine heads although only one rotary hook bed is to be positioned
inside the embroidering workpiece. As a result, combination embroidery with the plurality
of types of machine heads can be performed by one embroidery sewing machine smoothly
without any problem. Further, with the arrangement that the color change mechanism
for the multi-needle machine heads is caused to slide together with the horizontal
movement mechanism for the head groups, the present invention can significantly simplify
the construction of the entire horizontal movement mechanism.
Brief Description of Drawings
[0007]
Fig. 1 is a front view of an embroidery sewing machine in accordance with an embodiment
of the present invention;
Fig. 2 is a plan view showing the embroidery sewing machine with an upper machine
frame and machine heads omitted for clarity;
Fig. 3 is a sectional side view taken along the I - I line of Fig. 1;
- (a) of Fig. 4 is an enlarged front view of a color change mechanism and horizontal
movement mechanism of the embroidery sewing machine, and (b) of Fig. 4 is a plan view
of the color change mechanism and horizontal movement mechanism;
Fig. 5 is an enlarged side view of one of multi-needle machine heads;
Fig. 6 is an enlarged side view of one of single-needle machine heads;
(a) of Fig. 7 is a front view showing, in further enlarged scale, an example specific
construction of the color change mechanism, and (b) of Fig. 7 is a sectional side
view of the color change mechanism;
(a) of Fig. 8 is a front view showing, in further enlarged scale, an example specific
construction of the horizontal movement mechanism, and (b) of Fig. 8 is a sectional
side view of the horizontal movement mechanism;
(a) of Fig. 9 is a front view showing, in a further enlarged scale, an example specific
construction of a mechanism for transmitting rotation of a main shaft motor to a machine's
main shaft disposed in a left region of the front of the sewing machine, and (b) of
Fig. 9 is a sectional side view of the rotation transmission mechanism;
(a) of Fig. 10 and (b) of Fig. 10 are a front view and plan view, respectively, showing
an example state in which the multi-needle machine head has been placed in positional
correspondence to a rotary hook bed; and
(a) of Fig. 11 and (b) of Fig. 11 are a front view and plan view, respectively, showing
an example state in which a desired sewing needle (color thread) has been selectively
slid via the color change mechanism of Fig. 10.
Best Mode for Carrying Out the Invention
[0008] Fig. 1 is a front view of an embroidery sewing machine in accordance with an embodiment
of the present invention, Fig. 2 is a plan view showing the embroidery sewing machine
with an upper machine frame 1 and machine heads 3 and 4 omitted for clarity, and Fig.
3 is a sectional side view taken along the I - I line of Fig. 1. Reference numeral
1 indicates the machine frame and 2 a machine table. The table 2 includes a vertically-movable
front table 2a. Six head pairs (groups), each comprising two types of machine heads
3 and 4, are provided on a front surface of the machine frame 1. One of the machine
heads 3 in each of the head pairs (groups) is a multi-needle lock-stitching machine
head having a plurality of (e.g., nine) sewing needles, while the other machine head
4 is a single-needle lock-stitching machine head intended for decorative embroidery
and capable of sewing a tape or the like. One rotary hook bed 5 provided with one
rotary hook 6 is disposed under each of the head pairs (groups). Base sash frame 7
is provided on the table 2 and driven to move two-dimensionally in X and Y directions
via frame drive sections 8 and 9. A plurality of embroidery frames 10 are supported
on the base sash frame 7 in corresponding relation to the rotary hook beds 5, and
a cylindrically-shaped embroidering workpiece, such as the body of a T-shirt, can
be set on each of the embroidery frames 10.
[0009] (a) of Fig. 4 is a front view showing, in enlarged scale, parts of a color change
mechanism 20 and horizontal movement mechanism 30, and (b) of Fig. 4 is a plan view
of the parts of the color change mechanism 20 and horizontal movement mechanism 30.
As clearly seen from Fig. 4, a pair of upper and lower guide rails 13, each composed
of a plurality of rails 13a connected in series, are disposed on the front surface
of the machine frame 1. The machine heads 3 and 4 of each of the head pairs are fixed
to a mounting plate 12 that is in turn fixed to a slider 14 movably provided on the
two guide rails 13. The machine heads 3 and 4 of each of the head pairs are slidable
relative to the machine frame 1. Fig. 5 is an enlarged side view of one of the multi-needle
machine heads 3, and Fig. 6 is an enlarged side view of one of the single-needle machine
heads 4.
[0010] As shown in Fig. 5, the multi-needle machine head 3 includes an arm 15 and a needle
bar case 16 slidably supported on the arm 15, and the needle bar case 16 includes
a plurality of (e.g., nine) sewing needles 17. As will be later described, the needle
bar case 16 is slid horizontally via the color change mechanism 20 so that any desired
one of the sewing needles 17 can be selectively positioned at a predetermined operating
position (selected position). Machine's main shaft 18 extends through each of the
machine heads 3 and 4, and, through rotation of the machine's main shaft 18, the sewing
needle 17 positioned at the operating position (selected position) in the multi-needle
machine head 3 and the sewing needle 19 in the machine head 4 are moved up and down.
[0011] The color change mechanism 20 for positioning a desired one of the plurality of (nine)
sewing needles 17 of the machine head 3 at a selected position is provided on the
front surface of the machine frame 1. The color change mechanism 20 too is fixed,
via a mounting plate 21, to the slider 14 slidably provided on the guide rails 13.
Thus, the color change mechanism 20 too is slidable relative to the machine frame
1. Fig. 7 shows, in a further enlarged scale, an example specific construction of
the color change mechanism 20, in which (a) is a front view of the color change mechanism
20 and (b) is a sectional side view of the color change mechanism 20.
[0012] As shown in Fig. 7, the color change mechanism 20 includes a frame member (base)
22 of a channel-like sectional shape fixed to the mounting plate 21, a ball screw
23 rotatably supported on the frame member 22, and a moving member 26 mounted on a
nut member 24 screwed on the ball screw 23 and slidable along guide shafts 25. Drive
motor 27 is fixed to the frame member 22 and has its motor shaft connected to one
end of the ball screw 23, to thereby constitute a drive section. Thus, by activation
of the drive motor 27, the ball screw 23 is rotated so that the moving member 26 is
caused to slide together with the nut member 24. Rod 28 is connected to the needle
bar case 16 of the machine head 3 of each of the head pairs and has one end connected
to the moving member 26, which thereby constitutes a slide drive member. As the moving
member 26 is slid by being driven by the drive motor 27, the needle bar case 16 is
slid in a left-right direction via the rod 28. As shown in Fig. 6, the machine head
4 has a hole 29 to permit passage therethrough of the rod 28.
[0013] As shown in Fig. 1 or 4, the horizontal movement mechanism 30 for causing each of
the head pairs and color change mechanism 20 to slide together is provided on the
front surface of the machine frame 1. Fig. 8 shows, in a further enlarged scale, an
example specific construction of the horizontal movement mechanism 30, in which (a)
is a front view of the horizontal movement mechanism 30 and (b) is a sectional side
view of the horizontal movement mechanism 30. As shown in Fig. 8, the horizontal movement
mechanism 30, which is constructed in a similar manner to the color change mechanism
20, includes a frame member 31 fixed to the machine frame 1, a ball screw 32 rotatably
supported on the frame member 31, and a moving member 35 mounted on a nut member 33
screwed on the ball screw 32 and slidable along guide shafts 34. Drive motor 36 is
fixed to the frame member 31 and has its motor shaft connected to one end of the ball
screw 32. The individual mounting plates 12 having the head pairs fixed thereto and
the mounting plate 21 having the color change mechanism 20 are interconnected via
a connecting rod 37, and the mounting plate 21 is connected with the moving member
35 of the horizontal movement mechanism 30 via the connecting rod 37. Thus, as the
drive motor 36 of the horizontal movement mechanism 30 is driven to cause the moving
member 35 to slide, the individual machine heads 3 and the color change mechanism
20 are caused to slide together in the horizontal (leftward or rightward) direction.
Then, either one of the machine heads 3 or 4 is placed in positional correspondence
to the rotary hook bed 5, so that embroidery sewing is performed using the thus-positioned
machine head 3 or 4. At that time, the machine's main shaft 18 is caused to slide
together with the machine heads 3 and 4. Fig. 4 shows a state of the machine in which
the single-needle machine head 4 is in positional correspondence to the rotary hook
bed 5, while Fig. 10 or 11 shows a state of the machine in which the multi-needle
machine head 3 is in positional correspond to the rotary hook bed 5.
[0014] Fig. 9 shows, in enlarged scale, an example specific construction of a mechanism
for transmitting rotation of a main shaft motor 43 to the machine's main shaft disposed
in a left region of the front of the machine, in which (a) is a front view of the
rotation transmission mechanism and (b) is a sectional side view of the rotation transmission
mechanism. As clearly seen from Fig. 9, a spline shaft 38 is connected to the left
end of the machine's main shaft 18. The spline shaft 38 has mounted thereon bearings
39 slidable along the axis of the spline shaft 38 and rotatable with the spline shaft
38. Main shaft pulley 40 and driven pulley 41 are fixed to the bearings 39. The main
shaft pulley 40 is connected, via a timing belt 42, with the main shaft motor 43 fixed
to the rear surface of the machine frame 1. The driven pulley 41 is connected with
a rotary hook shaft pulley 46 via a timing belt 44 and intermediate pulley 45. The
rotary hook shaft pulley 46 is fixed to one end portion of a rotary hook shaft 47.
As seen in Fig. 3, the rotary hook shaft 47 extends through the individual rotary
hook beds 5, and the rotary hook 6 in each of the rotary hook beds 5 is rotatable
by rotation of the rotary hook shaft 47. Thus, through activation of the main shaft
motor 43, the machine's main shaft 18 and rotary hook shaft 47 are rotated, so that
not only the sewing needle 17 or 19 is moved up and down but also the rotary hook
6 is rotated. Via the spline shaft 38 and spline bearings 39, the driving force of
the main shaft motor 43 is transmitted to the main shaft 18 with axial sliding movement
of the shaft 18 permitted. In Fig. 9, a position of the spline shaft 38 when the machine
head 4 is in positional correspondence to the rotary hook bed 5 (i.e., the state of
Fig. 4) is indicated by a solid line, while a position of the spline shaft 38 when
the machine head 3 is in positional correspondence to the rotary hook bed 5 (see Fig.
10) is indicated by an imaginary line.
[0015] The following paragraphs describe an example manner in which combination embroidery
sewing is performed in the instant embodiment.
First, a cylindrically-shaped embroidering workpiece is set on the embroidery frame
10, and then the embroidery frame 10 is mounted on the base sash frame 7. When decorative
embroidery sewing, such as sewing of a tape, is to be performed on the embroidering
workpiece, the single-needle machine head 4 in each of the head pairs is placed, via
the horizontal movement mechanism 30, in positional correspondence to the associated
rotary hook bed 5. Then, the main shaft motor 43 is activated so that the sewing needle
19 is moved up and down, the rotary hook 6 is rotated and the base sash frame 7 is
moved on the basis of embroidery data. In this manner, decorative embroidery sewing,
such as sewing of a tape, is performed by the single-needle machine head 4, during
which time up-and-down movement of any one of the sewing needles 17 in the multi-needle
machine head 3 that is not currently in positional correspondence to the rotary hook
bed 5 is inhibited through the well-known jump control.
[0016] When multi-color embroidery is to be performed, the multi-needle machine head 3 in
each of the head pairs is placed, via the horizontal movement mechanism 30, in positional
correspondence to the associated rotary hook bed 5, and then the sewing needle 17
of a desired color thread is selectively positioned at a predetermined position (selected
position) through driving by the color change mechanism 20. Fig. 11 shows a state
in which the sewing needle 17 of a desired color thread has been selectively positioned
at a predetermined operating position (selected position) through driving by the color
change mechanism 20. Then, the main shaft motor 43 is activated, so that the sewing
needle 17, positioned at the operating position (selected position), is moved up and
down, the rotary hook 6 is rotated and the base sash frame 7 is moved on the basis
of the embroidery data. In this manner, embroidery sewing, using the desired color
thread, is performed by the multi-needle machine head 3, during which time up-and-down
movement of any one of the sewing needles 19 in the single-needle machine head 4 that
is not currently in positional correspondence to the rotary hook bed 5 is inhibited
through the well-known jump control.
[0017] By selectively placing, through driving by the horizontal movement mechanism 30,
either one of the two types of machine heads 3 and 4 in positional correspondence
to the associated single rotary hook bed 5 as noted above, the instant embodiment
permits selective embroidery sewing by the two types of machine heads 3 and 4 although
only one rotary hook bed 5 is to be positioned inside the embroidering workpiece.
As a result, combination embroidery sewing on the cylindrically-shaped embroidering
workpiece can be performed by the single embroidery sewing machine smoothly without
any problem. Further, with the arrangement that the color change mechanism 20 is caused
to slide together with the machine heads 3 and 4, the instant embodiment allows a
color change operation to be readily performed in the multi-needle machine head 3
with the conventional construction and control. If a construction where the color
change mechanism 20 is not caused to slide is employed, then there arise needs for
an extra structure to permit sliding movement of the machine heads 3 relative to the
color change mechanism 20, control to calculate a sliding movement amount of the machine
head 3, etc. which would result in a considerably complicated construction of the
machine. However, the present invention can eliminate such complexity and thereby
achieve a simplified construction.
[0018] Whereas the slide drive mechanism of the color change mechanism 20 and the slide
drive mechanism of the horizontal movement mechanism 30 in the embodiment have been
described above as ball-screw-based rotary-to-linear converting structures, the present
invention is not so limited, and the slide drive mechanisms may be other suitable
structures, such as cam-based rotary-to-linear converting structures or linear-motor-based
linear movement structures. Further, the two types of machine heads in each of the
head pairs (groups) are not limited to a combination of multi-needle and single-needle
machine heads, and alternatively both of the two machine heads may be multi-needle
machine heads. In the case where the two machine heads are multi-needle machine heads,
it is possible to increase the number of thread colors that can be used; in this case,
one color change mechanism 20 can be shared between the paired multi-needle machine
heads. Further, each of the head groups may comprise three different types of machine
heads. Furthermore, the present invention is applicable to not only to multi-head
sewing machines but also sewing machines provided with only one head pair or head
group comprising two or more machine heads.
1. An embroidery sewing machine for a cylindrically-shaped embroidering workpiece, said
embroidery sewing machine comprising:
a head group comprising two or more machine heads disposed in proximity to each other
so that each of the machine heads can perform embroidery sewing on an embroidering
area of an embroidery frame on which the cylindrically-shaped embroidering workpiece
is set, at least one of the two or more machine heads being a multi-needle machine
head having a plurality of needles;
a color change mechanism for selectively positioning a desired one of the needles
at a predetermined operating position in the multi-needle machine head;
a rotary hook bed provided for each of the head group for shared use between the machine
heads in the head group and corresponding to one said embroidering workpiece; and
a horizontal movement mechanism for disposing individual ones of the machine heads
and said color change mechanism for horizontal movement relative to the rotary hook
beds and horizontally moving the individual machine heads and said color change mechanism
together to place any one of the machine heads in each of the head groups in positional
correspondence to said rotary hook bed.
2. An embroidery sewing machine as claimed in claim 1 wherein a plurality of the head
groups are arranged horizontally at predetermined intervals and a plurality of the
rotary hook beds are arranged horizontally at predetermined intervals in corresponding
relation to the plurality of the head groups, and wherein said horizontal mechanism
moves the plurality of the head groups and said color change mechanism together horizontally
relative to the rotary hook beds.
3. An embroidery sewing machine as claimed in claim 1 or 2 wherein each of the multi-needle
machine heads in each of the heads groups includes a slidable needle bar case having
a plurality of sewing needles arranged horizontally,
said color change mechanism includes a slide drive member connected to the needle
bar case of each of the multi-needle machine heads, a drive section for selectively
positioning a desired one of the needles of each of the needle bar cases at a predetermined
operating position by driving said slide drive member to slide by a predetermined
amount, and a base having said drive section fixed thereto,
the machine heads in each of the head groups are interconnected via a mounting plate,
the mounting plate being mounted for horizontal movement relative to a machine frame
so that each of the machine heads is movable horizontally relative to the machine
frame, and
said horizontal movement mechanism includes an interlocking member interconnecting
the mounting plate and the base of said color change mechanism and a drive mechanism
for horizontally moving the interlocking member, the interlocking member being horizontally
moved by the drive mechanism so that each of the machine heads and said color change
mechanism are horizontally moved together.