TECHNICAL FIELD
[0001] This disclosure generally relates to a sewing machine.
BACKGROUND DISCUSSION
[0002] A sewing machine equipped with a function commonly known as a free-motion stitching
function, the function configured to process embroidery by fitting a workpiece in
a needlework frame and manually moving the needlework frame on a bed portion of the
sewing machine, is known. For example, in
JP2010-207542A (hereinafter referred to as Patent reference 1), a sewing machine including a sewing
needle at a lower side of a sewing head portion, a darning foot which repeats pressing
and detaching motions synchronized with a movement of the sewing needle on the workpiece,
and a button-hole switch portion equipped near and facing the sewing needle configured
to control a start and a stop of the button-hole stitching is disclosed. With the
disclosed sewing machine, an operator of the sewing machine operates the button-hole
switch equipped at a fixed position near the sewing needle with a finger tip to control
the start and the stop of the free-motion stitching function on performing a free-motion
stitching.
[0003] According to the known sewing machine in Patent reference 1, when the operator performs
the free-motion stitching to process the embroidery to the workpiece, the operator
normally uses the needlework frame for providing a tensioned state of the workpiece
and manually move the needlework frame back and forth and around between hands of
the operator to bring the needlework frame to a desired needlework position.
[0004] In such an occasion, the needlework operation becomes easier when the operator holds
the needlework frame from opposite sides with both hands and moves the needlework
frame to a desired position with respect to a base portion, for example, a bed portion
or an extension table. With the sewing machine of the aforementioned configuration,
the operator controls the start and stop switch for the free-motion stitching, the
switch equipped on the button-hole switch lever that is fixed to a position near the
sewing needle, by the finger tip of one hand while holding the needlework frame by
both hands. As a result, the operator may face an operational difficulty. Thus, an
operational improvement is desired so that the operator may process a needlework with
an operational ease and accuracy. Without such improvement, the operator using a large
size needlework frame may face a situation where the finger tip of the operator does
not reach the start and stop switch for the free-motion stitching when the operator
intends to process the needlework around the center of the needlework frame, especially
for the operators with small fingers operating the aforementioned sewing machine.
[0005] A need thus exists for a sewing machine that improves ease of use on performing a
free-motion stitching by moving the workpiece by hand and simultaneously enables more
subtle adjustments of the sewing needle movements.
SUMMARY
[0006] According to an aspect of the disclosure, a sewing machine for processing a needlework
on a workpiece by manually moving the workpiece on a base portion to a desired position
by an operator includes a sewing needle processing the needlework on the workpiece
on the base portion, a drive source actuating the sewing needle, a control portion
controlling the drive source, an operation portion electrically connected to the control
portion and variably operating the sewing needle, and the operation portion configured
to be attached to a periphery of a frame portion for providing a tensioned state of
the workpiece.
[0007] Instead of providing the operation portion at a fixed position on the sewing machine
as with a conventional sewing machine, the operation portion is provided at the periphery
of the frame portion for providing the tensioned state of the workpiece, so that the
operator may operate the operation portion at a position close to a hand which the
operator of the sewing machine holds and supports the frame portion. Having the operation
portion close to the hand of the operator provides the operator more ease on controlling
the movement of the sewing needle more sensitively relative to the conventional sewing
machine. Even while the operator is using the needlework frame with a large diameter
by holding the needlework frame with palms, the operator may control the operation
portion with a fingertip, for example, of an index finger or a middle finger. As a
result, when processing the needlework to the workpiece, the operator may control
the movement of the sewing needle with more sensitivity and with ease, for processing
the needlework of a desired design, having sewing patterns, embroideries and characters
for example, at a desired position.
[0008] According to the further aspect of the disclosure, the sewing machine includes an
attachment portion arranged between the operation portion and the frame portion for
the operator to change a direction of an operational surface to and from a vertical
direction and a horizontal direction relative to the frame portion on the base portion.
[0009] The attachment portion is provided between the operation portion and the frame portion
for the operator to change the direction of the operational surface to and from a
vertical direction and a horizontal direction relative to the frame portion on the
base portion, so that the operator of the sewing machine using the frame portion manually
may change the direction of the operational surface by changing the attachment portion
for changing the position of the operation portion to and from a vertical direction
and a horizontal direction relative to the frame portion according to the ease of
use by the operator with a simple structural understanding and an easy operation.
The sewing machine provides selections according to the liking of operation by the
operator for providing more ease of operation to the operator. As a result, the operator
is provided with an advantage of having to control the needlework operation with more
sensitivity for processing the needlework of a sensitive design.
[0010] According to another aspect of the disclosure, the sewing machine includes the operation
portion equipped with an operation switch of variable resistance type.
[0011] When the operation portion adopts the operation switch of a variable resistance type,
the operator may control the movement of the sewing needle in a continuously changing
manner in, for example, a stitch width (a distance to move the sewing needle), a speed
to move the sewing needle in an up and down direction, and the speed to move the sewing
needle in the horizontal direction. As a result, the operator is provided with the
advantage of having to control a more sensitive three-dimensional movement of the
sewing needle.
[0012] According to the further aspect of the disclosure, the sewing machine includes the
operation portion equipped with a retaining portion in a clip form configured to retain
an object for retaining. The operation portion is configured to attach to and detach
from an object retained by the retaining portion.
[0013] The operation portion equipped with the retaining portion in the clip form may attach
to and detach from an object retained by the retaining portion. For example, the retaining
portion may directly retain the workpiece when the operator process the needlework,
for example an embroidery, to the workpiece without using the frame portion by retaining
the workpiece directly by hand to provide the tensioned state of the workpiece. In
this instance, the operator may retain the operation portion at a desired position,
which is close to the hand retaining the workpiece. When the position of the workpiece
is moved by hand, the operation portion is moved together with the workpiece being
moved. In other words, the operation portion is positioned consistently close to the
hand in order to sensitively control the movement of the sewing needle with ease.
[0014] According to another aspect of the disclosure, the sewing machine includes the operation
portion equipped with the retaining portion in the clip form configured to directly
retain the workpiece.
[0015] The operation portion equipped with the retaining portion in the clip form may directly
retain the workpiece when the operator process the needlework, for example the embroidery,
to the workpiece without using the frame portion by retaining the workpiece directly
by hand to provide the tensioned state of the workpiece. In this instance, the operator
may retain the operation portion at a desired position, which is close to the hand
retaining the workpiece. When the position of the workpiece is moved by hand, the
operation portion is moved together with the workpiece being moved. In other words,
the operation portion is positioned consistently close to the hand in order to sensitively
control the movement of the sewing needle with ease.
[0016] According to further aspect of the disclosure, the sewing machine includes the operation
portion being detached from the frame portion configured to be placed within a pedal
portion provided for a foot operation by the operator to variably control a movement
of the sewing needle according to a foot operated amount by the operator.
[0017] The operation portion being detached from the needlework frame is disposed within
the pedal portion that is configured to be stepped on by the operator for operation,
so that the operator may control the sewing needle movement according to the amount
the pedal portion is pressed by foot. As a result, the operator may select to use
the operation portion as a foot controller to be controlled by foot depending on the
ease of operation.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The foregoing and additional features and characteristics of this disclosure will
become more apparent from the following detailed description considered with the reference
to the accompanying drawings, wherein:
[0019] Fig. 1 is a perspective view of a sewing machine according to a first embodiment;
[0020] Fig. 2 is a block diagram showing a control system configuration of the sewing machine
illustrated in Fig. 1;
[0021] Fig. 3A is a drawing illustrating an attachment condition of an operation portion
(i.e. an attachment configuration A) where the operation portion is attached laterally
relative to a needlework frame;
[0022] Fig. 3B is a drawing illustrating an attachment condition of an operation portion
(i.e. an attachment configuration B) where the operation portion is attached perpendicularly
relative to the needlework frame;
[0023] Fig. 4 is a perspective view of the operation portion with the needlework frame where
the operation portion is attached perpendicularly relative to the needlework frame;
[0024] Fig. 5 is a drawing describing a structure to attach the operation portion to the
needlework frame in the attachment configuration A;
[0025] Fig. 6 is a drawing illustrating the operation portion illustrated in Fig. 1 being
disassembled to describe an internal structures;
[0026] Fig. 7 is a perspective view of the operation portion integrated with the needlework
frame according to a second embodiment;
[0027] Fig. 8 is a perspective view of the operation portion according to a third embodiment
showing the position on the operation portion where to equip a retaining portion that
retains the operation portion;
[0028] Fig. 9 is a drawing illustrating substantial parts of a clip structure of the retaining
portion being enlarged;
[0029] Fig. 10 is a drawing describing the operation portion according to a fourth embodiment
to be contained internally in an upper case; and
[0030] Fig. 11 is a cross-sectional view of the upper case illustrated in Fig. 10 describing
a position of the operation portion being contained therein.
DETAILED DESCRIPTION
[0031] Embodiments of a sewing machine 1 will be described as follows referring to Figures.
[0032] A first embodiment of the sewing machine 1 will be described as follows. Fig. 1 is
a perspective view of the sewing machine 1 according to a first embodiment, and Fig.
2 is a block diagram showing a control system configuration of the sewing machine
1 illustrated in Fig. 1.
[0033] As shown in Fig. 1, the sewing machine 1 includes a main body 1a of the sewing machine
1 and an operation portion 10 with which an operator of the sewing machine 1 controls
the movement of a sewing needle 2. The main body 1 a of the sewing machine 1 includes
a bed portion 1b, which serves as a base portion, having a flat upper surface where
a needlework, for example an embroidery, is processed, an upright arm portion 1c that
vertically erects from an end of the bed portion 1b, a horizontal arm portion 1 d
that extends from an upper end of the upright arm portion 1 c facing and being parallel
to the bed portion 1b, and a sewing head portion 1 e that extends downward from a
free end of the horizontal arm portion 1d being extended.
[0034] The sewing needle 2 to stitch the needlework, for example the embroidery, is attached
to a lower portion of the sewing head portion 1e. With the sewing machine 1 having
such a configuration, the sewing needle 2 is driven up and down or to right and left
by drive sources 3 (a first drive source 3a and a second drive source 3b), which is
controlled by a controller 4, which serves as a control portion, as shown in Fig.
2.
[0035] An extension table K may be attached to a free end of the bed portion 1 b, which
serves as the base portion of the sewing machine 1 illustrated in Fig. 1, for ease
of operation to process the needlework, for example the embroidery, to a workpiece
100. An upper surface of the extension table K is a continuous surface in a same level
as an upper surface of the bed portion 1b. The extension table K is detachably attached
to fit into the bed portion 1 b. On the extension table K and the bed portion 1 b,
a needlework frame 50, which serves as a frame portion, is used when the needlework
is processed. On the extension table K and the bed portion 1b, the operator may manually
move the needlework frame 50, which provides a tensioned state of the workpiece 100
within the area being surrounded by the frame, to any desired direction, for example
closer to the operator, to a feed direction, or to a right and left of the operator,
for processing the needlework at a desired position.
[0036] The operation portion 10 according to the first embodiment is configured to manually
adjust the movement of the sewing needle 2 so that the operation to process the needlework
is easier when the operator of the sewing machine 1 performs a stitching method commonly
known as a free-motion stitching where the operator manually moves the workpiece 100.
[0037] As shown in Fig. 1, the operation portion 10 is selectively attached to a periphery
50a of the needlework frame 50 in an annular form.
[0038] An exterior of the operation portion 10 is formed with a casing 30 made of two parts
and shaped so that the operator may firmly hold the operation portion 10. The operation
portion 10 is equipped with an operation switch 20 having an operational surface 20a
that may be operated by the operator. The operation switch 20 is projected from a
surface that is formed when the two parts of the casing 30 mate with each other in
one direction. In Fig. 1, the operation switch is projected to a vertical direction
relative to the surface that is formed when the two parts of the casing 30 mate. The
casing 30 includes a first casing 31 having a U-shaped cross section and a second
casing 32 likewise having a U-shaped cross section. The first casing 31 and the second
casing 32 are joined at an end surface of each and retained in such state by means
of a screw or similar fixing member. As shown in Fig. 1, the operation switch 20 is
arranged on the surface of the operation portion 10 in the vertical direction, so
that the operator may operate the operation switch 20 by using for example a tip of
at least one of fingers, for example an index finger, a middle finger, or a thumb,
while maneuvering the needlework frame 50 to a desired position. The operation switch
20 adopts a variable resistance type switch. The operation switch 20 may be configured
with a switch type other than the variable resistance type when the switch may detect
a movement of the operator. For example, the operation switch 20 may be of a pressure
sensitive type, which provides continuously changing outputs with respect to the pressure
being provided by a finger operation.
[0039] The operation portion 10 according to the first embodiment adopts a harness H1, a
wire to establish an electrical connection between the main body 1a of the sewing
machine 1. A method to establish the connection is not limited to such, for example,
the connection between the operation portion 10 and the main body 1a of the sewing
machine 1 may be established wirelessly by radio, without using the harness H1.
[0040] With the sewing machine1 being disclosed here, when the sewing machine 1 is operated,
the operation of the operation switch 20 is converted to an electrical signal when
the operator manually operates the operational surface 20a of the operation switch
20. The converted operational signal is fed via the harness H1 as an input to the
controller 4, which serves as the control portion, built-in to the main body 1 a of
the sewing machine 1. When the controller 4 receives the operational signal from the
operation portion 10, the controller 4 sends an instruction to drive the first drive
source 3a and the second drive source 3b so that the sewing needle 2 is controlled.
[0041] When the operation switch 20 as illustrated in Fig. 1 is pressed at the operational
surface 20a by the operation of the operator, the operational surface 20a is pushed
into the casing 30 by the pressure. The operation switch 20 is configured to return
to the original position when the pressure is released. Such operational movements
are converted to electrical signals and fed to the controller 4 as the operational
signal input.
[0042] According to the first embodiment, the movement of the sewing needle 2 during the
needlework operation is variably controlled with a stitch width, which is a distance
that the sewing needle 2 moves horizontally relative to the bed portion 1b and the
extension table K. Instead, the movement of the sewing needle 2 may be variably controlled,
for example, with a sewing speed or a needle stop position.
[0043] The operation portion 10 may be attached in either a vertical position or a horizontal
position relative to the needlework frame 50, depending on the ease of operation of
the operator. The operation portion 10 may be attached to the periphery 50a of the
needlework frame 50 in a horizontal configuration as Fig. 3A illustrates, or in a
vertical configuration as Fig. 3B illustrates, and may change the configuration freely
depending on the ease of operation of the operator. Fig. 3A illustrates an attachment
configuration A, where the operation portion 10 is attached to the needlework frame
50 so that the operation switch 20 is operated by pressing in a horizontal direction.
Fig. 3B illustrates an attachment configuration B, where the operation portion 10
is attached to the periphery 50a of the needlework frame 50 so that the operation
switch 20 is operated by pressing in an upward and downward direction, that is in
the vertical direction relative to the bed portion 1b.
[0044] A structure of the needlework frame 50 according to the first embodiment is described
as follows. Fig. 4 is a perspective view of the operation portion 10 attached to the
periphery 50a of the needlework frame 50 in the attachment configuration B. The needlework
frame 50 tucks the workpiece 100 (shown in an imaginary line) between an upper frame
and a lower frame to provide the tensioned state of the workpiece 100 within the area
being surrounded by the frame. The needlework frame 50 includes an inner frame 51,
which is a frame in a position inward in a radial direction of the needlework frame
50, and an outer frame 52, which is a frame in the position outward in the radial
direction of the needlework 50, when the workpiece 100 is being tucked down between
the aforementioned frames. When the workpiece 100 is held between the inner frame
51 and the outer frame 52 and a tightening screw 21 equipped on the outer frame 52
is tightened by turning in a clockwise direction, a diameter of the outer frame 52
is reduced with respect to the inner frame 51, so that the workpiece 100 is retained
to the needlework frame 50. When the tightening screw 21 is turned in the direction
opposite to the direction turned to tighten, the workpiece 100 may be removed from
the needlework frame 50.
[0045] An attachment structure between the operation portion 10 and the needlework frame
50 is described next. As Fig. 4 illustrates, the operation portion 10 is attached
to the periphery 50a of the needlework frame 50 via an attachment member 60 made of
a metal (or of other material, for example, resin). In other words, between the operation
portion 10 and the attachment member 60 are retained, and between the attachment member
60 and the needlework frame 50 are retained. The attachment details are described
based on Fig. 5 as follows. Fig. 5 is a drawing describing the attachment structure
with major portions being enlarged for the attachment configuration A.
[0046] In Fig. 5, the inner frame 51 of the needlework frame 50 includes a bottom surface
54 having a horizontal plane that is configured to be placed on and contact in a plane
to the bed portion 1 b during the needlework operation, a top surface 55 at the side
opposite to the bottom surface 54, a first extended portion 56 that extends horizontally
inward in a radial direction from an inner portion of the top surface 55, and a second
extended portion 57 that extends horizontally outward in a radial direction to a length
nearly five times longer than the first extended portion 56 from an outer portion
of the top surface 55. A top surface of the first extended portion 56 and a top surface
of the second extended portion 57 are portions consisting of the top surface 55 of
the needlework frame 50.
[0047] The attachment member 60, which fits to and retains the needlework frame 50, includes
a frame retaining portion 61 that attaches to the first extended portion 56 and the
second extended portion 57 at the top surface of the inner frame 51 and a casing retaining
portion 62 that extends vertically from the frame retaining portion 61, which fits
to at least one side of and retains the operation portion 10 in a vertical configuration
or in a horizontal configuration. The frame retaining portion 61 attaches to the top
surface side of the inner frame 51 by engaging with the first extended portion 56
and the second extended portion 57 of the inner frame 51. The casing retaining portion
62 includes a portion in a plate form extending from a one end side of the frame retaining
portion 61 in a lateral direction. As shown in Fig. 5, the one end side is the side
outward in a radial direction of the inner frame 51, when the attachment member 60
is attached to the inner frame 51. The aforementioned lateral direction is the direction
in an axial direction of the inner frame 51, when the attachment member 60 is attached
to the inner frame 51. According to the first embodiment, as shown in Fig. 5, the
casing retaining portion 62 in a plate form, which extends from the one end side of
the frame retaining portion 61, is equipped in a vertically upward direction in the
axial direction of the inner frame 51. According to the first embodiment, the frame
retaining portion 61 and the casing retaining portion 62 are integrally formed with
a metal, which may be formed with other materials, for example, resin.
[0048] In addition, the casing retaining portion 62 includes a hook portion 63, which serves
as an attachment portion, in a distal end side 62a. The attachment portion 63 is L-shaped
and hooks and fits to the casing 30 of the operation portion 10 when attaching the
operation portion 10 thereto. The hook portion 63, which projects outward in a radial
direction relative to the casing retaining portion 62, is equipped in multiple numbers,
for example two in the first embodiment, so that the operation portion 10 is stably
retained. The hook portion 63 includes a third extended portion 64 that extends from
a portion between the distal end side 62 and a proximal end side 62b of the casing
retaining portion 62 and a fourth extended portion 65 that extends vertically upward
from a distal end side of the third extended portion 64. In other words, the casing
retaining portion 62, the third extended portion 64, and the fourth extended portion
65 together form a key shape. Surrounded by the third extended portion 64, the fourth
extended portion 65 and the distal end side 62a of the casing retaining portion 62,
a groove portion 66 is formed. The groove portion 66 is configured to retain the operation
portion 10 by hooking at an opening 33, to be further described later, which is formed
on a side of the casing 30 of the operation portion 10. On at least one side of the
operation portion 10, two hooking structures of the aforementioned are formed between
the casing retaining portion 62 and the casing 30. In Fig. 5, only one of the two
hooking structures is shown.
[0049] An attachment portion of the casing 30 to be attached to the hook portion 63 of the
attachment member is described next. As shown in Fig. 5, the first casing 31 and the
second casing 32, each having a substantially U-shaped cross section, are joined at
the fitting surface at each end and are retained by a method, for example, an ultrasonic
welding, to form the casing 30. According to the first embodiment, the casing 30 is
formed with the opening 33 on the side to be attached to the casing retaining portion
62. According to the first embodiment, as shown in Fig. 5, the opening 33 is formed
on one side of the second casing 32, which is configured to be held firmly by the
operator. At an end of the opening 33, a tucking portion 32a of the second casing
32 fits between the casing retaining portion 62 and the fourth extended portion 65
and is retained thereat. Fig. 5 illustrates that the tucking portion 32a is formed
in the vertical direction similarly to the casing retaining portion 62 and the fourth
extended portion 65.
[0050] To attach the operation portion 10 to the attachment member 60, the hook portion
63 projected outward is inserted into the opening 33 formed on the second casing 32
and slides the operation portion 10 vertically downward. In doing so, the tucking
portion 32a is inserted to the groove portion 66 of the hook portion 63. As a result,
the casing retaining portion 62 and the operation portion 10 are retained to each
other.
[0051] An internal structure of the operation portion 10 is described next. As shown in
Fig. 6, the operation portion 10 is internally equipped with switch elements 40, which
compose the operation switch 20. The switch elements 40 are assembled to the second
casing 32 side. After the switch elements 40 are assembled, the second casing 32 is
covered with the first casing 31 and is retained in a closed state with a screw, by
welding or other retaining means to form the operation portion 10.
[0052] The switch elements 40 include, as principal parts, a switch portion 41 that the
operator operates with a finger, a variable resister board 42 equipped with variable
resister portions 42a, 42b, referred to as resister board patterns as necessary, that
detects a resistance value based on the pressed amount of the switch portion 41, a
lever 43 for a contact fitting 43b equipped with the contact fitting 43b that divides
the resistance value detected by the variable resister portions 42a, 42b relative
to the pressed amount of the switch portion 41, and a spring 44 disposed between the
second casing 32 and the switch portion 41 to bias the switch portion 41 pressed by
the operator back to the original position.
[0053] The switch portion 41 is rotationally supported to rotate at a first rotational portion
32b, projecting internally from the second casing 32 as center, as shown in Fig. 6.
The switch portion 41 includes an operational surface 41a having a smoothly slanted
surface where the operator operates as a switch with a body portion, for example a
left hand finger, when the operator operates the sewing machine 1. The operational
surface 41 a is disposed in a state to project outward from a peripheral end of the
casing 30 of the operation portion 10. The operator presses and releases the operational
surface 41 a with, for example, a finger to operate the sewing machine 1, so that
the operator may perform the needlework while keeping on checking the sewing state.
[0054] The spring 44 is assembled to the first rotational portion 32b and biases the switch
portion 41 pressed by the operator to a direction to return to the original position,
which is a clockwise direction in Fig. 6.
[0055] The lever 43 for the contact fitting 43b, which rotates in relation to a rotation
of the switch portion 41, is rotationally supported with respect to the variable resister
board 42 retained internally to the second casing 32 and rotates in an amount relative
to the pressed amount of the switch portion 41. An end of the lever 43 for the contact
fitting 43b is rotationally supported at a second rotational portion 43a as center
and the other end is arranged to move by pressing the switch portion 41. In other
words, one end of the lever 43 for the contact fitting 43b is rotationally supported
and the other end is configured to move rotationally with respect to the variable
resister board 42 being retained when the operational surface 41 a is pressed with
the switch portion 41. The lever 43 for the contact fitting 43b returns to the original
position with the biasing force of the spring 44 when the pressure from the pressing
is released. The lever 43 for the contact fitting 43b is provided with the contact
fitting 43b of electrically conductive material, for example copper, at a location
between one end and the other end of the lever 43 for the contact fitting 43b. The
contact fitting 43b is pushed to a direction of the variable resister board 42 by
rotating together with the lever 43 for the contact fitting 43b when the switch portion
41 is pressed for operation. The contact fitting 43b is connected to the variable
resister portions 42a, 42b, provided on the variable resister board 42. When the lever
43 for the contact fitting 43b is pressed for operation, the contact fitting 43b moves
slidingly on the variable resister portions 42a, 42b. Upon this movement of the contact
fitting 43b, when a predetermined voltage, for example 5V, is applied to terminals
at ends of the variable resister portions 42a, 42b, a short circuit position changes
and an internal resistance of the variable resister board 42 changes. As a result,
a voltage according to the operation amount of the operational surface 41 a is successively
detected.
[0056] Although with the first embodiment, the switch portion 41 and the lever 43 for the
contact fitting 43b are formed and assembled independently, the switch portion 41
and the lever 43 for the contact fitting 43b may be integrally formed and assembled
as one component. In this instance, a total number of parts and total man-hour for
assembly may be reduced.
[0057] The variable resister board 42 is provided internally in the operation portion 10
at a position where the switch portion 41 is being pushed in, in other words, on a
rotational path of the switch portion 41 as Fig. 6 shows. The variable resister board
42 includes resistors 42c, the variable resistor portion 42a (the resister board pattern),
which is electrically connected to the resistors 42c, the variable resistor portion
42b (the resister board pattern), which is electrically connected to the variable
resistor portion 42a via the contact fitting 43b. The variable resistor portion 42a
(the resister board pattern) and the variable resistor portion 42b (the resister board
pattern) are electrically connected at a side where the switch portion 41 is provided.
When the contact fitting 43b moves, the position connected with the variable resistor
portions 42a, 42b, which is the short circuit position, changes, so that the resistance
value between terminals that are not short circuited, which are a first terminal portion
Ta and a second terminal portion Tb, changes. To each of the first terminal portion
Ta and the second terminal portion Tb, an internal harness H2 of an electrically conductive
material is connected, for example, by soldering. Each of the other end of the internal
harnesses H2 are electrically connected to a first connector A, which is provided
at an end in a longitudinal direction of the casing 30.
[0058] As shown in Fig. 1, at the first connector A, which is provided on the operation
portion 10 and at a second connector B, which is provided on a side at a vertically
lower location of the main body 1a of the sewing machine 1, opposite ends of the external
harness H1 is detachably attached to provide an electrical connection. The second
connector B is electrically connected by another harness with the controller 4, which
is internally provided in the sewing machine 1.
[0059] The controller 4, which serves as the control portion, is electrically connected
with the drive sources 3 (the first drive source 3a and the second drive source 3b),
as shown in Fig. 2. The controller 4 controls the drive sources 3 according to the
changes of internal resistance in the variable resister board 42, which is internally
provided in the operation portion 10.
[0060] The drive sources 3 includes the first drive source 3a, which is the drive source
to move the sewing needle 2 up and down, and the second drive source 3b, which drives
the sewing needle 2 in a reciprocating motion in the horizontal direction for controlling
the stitch width. The drive sources 3 are driven based on instructions from the controller
4.
[0061] In the first embodiment, the controller 4 sends an instruction based on the change
in the resistance value of the variable resister board 42, which is internally provided
in the operation portion 10, to the second drive source 3b for controlling the second
drive source 3b. As a result, the operator may control the stitch width, the distance
to move the sewing needle 2, by operating the operational surface 41 a of the operation
portion 10. In addition to varying the distance to move the sewing needle 2, the second
drive source 3b may be configured to vary a speed to move the sewing needle 2 in an
up and down direction and the horizontal direction for providing more sensitive three-dimensional
movement of the sewing needle 2.
[0062] With the sewing machine 1 according to the first embodiment, the operator of the
sewing machine 1 may control the operation portion 10 at a position closer to a hand
by using a finger, for example the index finger, while holding and supporting the
needlework frame 50 manually. In this instance, a sensitive movement of the sewing
needle 2 is controlled with ease. Even when the operator is using the needlework frame
50 with a large diameter, the sewing machine 1 according to the first embodiment is
advantageous in that the operator may control the operation portion 10 at a position
close to the hand holding the needlework frame 50 so that the operator may control
the operation portion 10 at the fingertip. As a result, when processing needlework
to the workpiece 100, the operator may control the movement of the sewing needle 2
with more sensitivity and with ease, for processing needlework of a desired design.
[0063] An attachment configuration to the needlework frame 50 of the operation portion 10
according to the first embodiment is selectable between the configuration in which
the operational surface 41a is at a top or at a side depending on the ease of the
operator. The operator may attach the operation portion 10 to the needlework frame
50 in the configuration of a choice based on the ease of operation. By selecting the
attachment configuration such that provides the operational surface 41 a of the operation
portion 10 near to the fingertip for operation, the operation to process sensitive
needlework by the operator, who holds the needlework frame 50 with both hands and
controls the movement of the sewing needle 2 using the fingertip, becomes easier.
[0064] Adopting the variable resistance type switch for the operation switch 20 is advantageous
in providing a sensitive movement of the sewing needle 2 (the stitch width of the
sewing needle 2) in a continuously changing manner at a reduced cost.
[0065] The sewing machine 1 according to the second embodiment is described as follows.
Fig. 7 is a perspective view of the operation portion 10 according to a second embodiment
[0066] Aside from the operation portion 10 being integrally formed in resin with the needlework
frame 50, as shown in Fig. 7, the configuration of the second embodiment is similar
to the configuration of the first embodiment. The second embodiment is mainly described
with the differences from the first embodiment as follows.
[0067] The operation portion 10 according to the second embodiment is integrally formed
with the inner frame 51 of the needlework frame 50, which extends outward in a radial
direction from an outer periphery side of the inner frame 51. The operation switch
20 of the operation portion 10 is provided on a surface at the distal end of the portion
extended from the inner frame 51. The external harness H1 for the electrical connection
to the main body 1a of the sewing machine 1 is connected to one of the side portions
of the portion extended from the inner frame 51.
[0068] According to the configuration according to the second embodiment, because the operation
portion 10 is integrally formed with the inner frame 51 of the needlework frame 50,
the attachment member 60 provided with the first embodiment for attaching the operation
portion 10 to the needlework frame 50 is unnecessary. As a result, a configuration
in a periphery of the needlework frame may be simplified, the cost to provide the
configuration may be reduced, and the ease of operation by the operator moving the
needlework frame 50 to process the needlework is improved.
[0069] The sewing machine 1 according to the third embodiment is described as follows. Fig.
8 is a perspective view describing characteristics of the operation portion 10 according
to the third embodiment. Fig. 9 is a drawing illustrating substantial parts of a clip
structure of a retaining portion 80 shown in Fig. 8 being enlarged.
[0070] Aside from having the retaining portion 80 in a clip structure being fixed to one
side of the operation portion 10 as a difference, as shown in Fig. 8, the configuration
of the third embodiment is similar to the configuration of the first embodiment. The
third embodiment is mainly described with the differences from the first embodiment
as follows.
[0071] The operation portion 10 according to the third embodiment detachably attaches to
the needlework frame 50 with a clip structure, which is the retaining portion 80 such
that retains the workpiece 100 for processing with an easy operation when the operator
processes the needlework to the workpiece 100.
[0072] The retaining portion 80 is provided on one surface, the surface for example on a
side, of the first casing 31, which is one member consisting of the casing 30 of the
operation portion 10, as shown in Fig. 8. In detail, the retaining portion 80 is provided
on the surface perpendicular to the surface where the operation switch 20 is provided.
[0073] The retaining portion 80 includes a first plate 81 having a pivot point 81 c at a
location near the middle of a first end 81 a and a second end 81 b of the first plate
81 where the first plate 81 rotates as the center, a second plate 82 configured to
hold the workpiece 100 between the first plate 81 at the first end 81a, and a biasing
member 83, for example a torsion spring, for biasing the first end 81a of the first
plate 81 in a direction of the second plate 82, which is a counterclockwise direction
in Fig. 9, as main portions. According to the third embodiment, one surface (the surface
on the side, for example) of the first casing 31 is serving the purpose of the second
plate 82, as Fig. 8 shows.
[0074] When the operator presses the second end 81 b of the first plate 81 to the direction
of the first casing 31, the first plate 81 rotates with the pivot point 81c as the
center in clockwise direction in Fig. 9, that is in the direction where the first
end 81 a of the retaining portion 80 detaches from the first casing 31 (the second
plate 82) to define a space therebetween. When the workpiece 100 is inserted to the
aforementioned space and the pressure at the second end 81 b is released, the first
end 81 a of the first plate 81 returns to the original position by a biasing force
of the biasing member 83, which is the position shown in Fig. 9. As described above,
with the simple configuration and operation, the operation portion 10 may be easily
retained to the workpiece 100.
[0075] The configuration according to the third embodiment allows the operator to retain
the operation portion 10 at a position close to the hand holding the workpiece 100
when processing the needlework (embroidery, for example) to the workpiece 100 by retaining
the workpiece 100 directly by hand without using the needlework frame 50. In this
instance, when the position of the workpiece 100 is moved by hand, the operation portion
10 is moved together with the workpiece 100 being moved. In other words, the operation
portion is positioned consistently close to the hand in order to sensitively control
the movement of the sewing needle 2 with ease.
[0076] The sewing machine 1 according to the fourth embodiment is described as follows.
Fig. 10 is a drawing describing the operation portion 10 according to a fourth embodiment
to be contained internally in an upper case 91, which serves as a pedal portion. Fig.
11 is a cross-sectional view showing an internal configuration of the operation portion
10 according to the fourth embodiment.
[0077] Aside from the operation portion 10 configured to be used as a foot controller 90
for operating the sewing machine 1 with a pedal operation as the difference, the configuration
of the fourth embodiment is similar to the configuration of the first embodiment.
The fourth embodiment is mainly described with the differences from the first embodiment
as follows.
[0078] With the fourth embodiment, the operation portion 10, as shown in Fig. 1, which detachably
attaches to the needlework 50, is detached from the needlework frame 50. The fourth
embodiment is
characterized in that the upper case 91 (the pedal portion) of a detachable state, which the operator may
operate as a pedal, being disposed on the surface of the operation switch 20, so that
an amount pressed by the foot of the operator becomes the amount of the operation
switch 20 being pressed.
[0079] The foot controller 90 includes, the upper case 91 (the pedal portion) having a surface
92a for the operator to step on, the operation portion 10 disposed at a flip side
of the surface 92a of the upper case 91 and operated according to the amount the upper
case 91 being pressed by the foot, and a lower case 95 for containing the operation
portion 10, as principal portions.
[0080] The upper case 91 includes a third plate 92 having the surface 92a for the operator
to step on and first peripheral walls 93 extending downward from peripheral portions
of the third plate 92. The upper case 91 is a box form with the lower portion being
open. One end of the upper case 91 is rotationally supported by the lower case 95
so that the upper case 91 is rotational with respect to the lower case 95. The upper
case 91 is configured to contain the lower case 95 internally, when the operator steps
on the surface 92a. On a reverse surface 92b, which is the flip side of the surface
92a of the third plate 92, a protruded portion 92c is provided for pressing the operation
switch 20 of the operation portion 10. The protruded portion 92c is provided closer
to another end 92d of the upper case 91, a free end opposite to the end being rotationally
supported by the lower case 95. The protruded portion 92c is provided for pressing
the operation switch 20 with more ease.
[0081] The lower case 95 includes a fourth plate 96 that provides a bottom portion, second
peripheral walls 97, extending upward from peripheral portions of the fourth plate
96. The lower case 95 is a box form with the upper portion being open. One end of
the lower case 95 rotationally supports the upper case 91. The lower case 95 is configured
to be surrounded by the upper case 91 when the operator steps on the surface 92a.
Inside thereof, the lower case 95 is provided with an open space 95a where the operation
portion 10 is disposed and a positioning member 95b for retaining the position of
the operation portion 10 disposed in the open space 95a.
[0082] The operation portion 10 is inserted into the lower case 95 in a state in which the
upper case 91 is rotated in an opening direction with respect to the lower case 95,
then the upper case 91 is rotated in a closing direction to contain the operation
portion 10 inside the foot controller 90. The operation portion 10 is positioned so
that the protruded portion 92c contacts the operation switch 20.
[0083] As can be seen from above, when the operation portion 10, detachably attached to
the needlework frame 50 being detached from the needlework frame 50, is provided with
the upper case 91 (the pedal portion) in a detachable state configured to be stepped
on by the operator being positioned at the surface of the operation switch 20, the
operator may operate the operation switch 20 according to the amount the upper case
91 (the pedal portion) is pressed by foot. In such a case, the operator may select
to use the operation portion 10 as a foot controller 90 to be controlled by foot depending
on the ease of operation.