Embroidery sewing machine with embroidery frame type detecting function

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to an embroidery sewing machine to which one of a plurality of embroidery frames is exchangeably attached.

2. Description of the Related Art

There have conventionally been provided sewing machines to which one of a plurality of embroidery frames is exchangeably attached according to the size of a workpiece cloth or the area of a sewing region. In the sewing machines of this type, the type of an attached embroidery frame needs to be detected in order that an origin of the sewing region may be determined or the sewing region may be detected. For example, JP-A-6-319880 discloses a sewing machine comprising a rock arm extending downward from a distal end of a sewing arm and a retractable lever mounted on a lower end of the rock arm. In the disclosed sewing machine, the embroidery frame is moved in the positive and negative directions on the X-axis while an abutting portion provided on the lower end of the retractable lever is located within the attached embroidery frame, so that the abutting portion is caused to abut both front and rear of the embroidery frame. The size of the attached embroidery frame is detected on the basis of two locations of the abutting portion.

In the foregoing sewing machine, however, the embroidery frame is attached to the sewing machine and subsequently moved in the two X directions so that the type of the embroidery frame is detected. As a result, the detection of the embroidery frame type takes much time. Further, when the operator has attached an erroneous embroidery frame or an embroidery frame with a sewing region which does not correspond to embroidery data, the operator is informed of the error by means of an error message or the like after the embroidery frame has been attached and its type has been detected. The operator needs to detach the erroneous embroidery frame, rearrange the workpiece cloth onto a correct embroidery frame, and attach the correct embroidery frame to the sewing machine. Thus, replacement of embroidery frame results in waste of time and labor.

As another example, JF-A-2002-52283 discloses an embroidery sewing machine in which one of a plurality of embroidery frames is exchangeably attached to a carriage of an embroidery frame moving mechanism provided on the sewing bed. In the disclosed construction, each embroidery frame includes a connecting portion having concavo-convex patterns (presence or absence of projection) formed at three juxtaposed detecting positions respectively and peculiar to every type of embroidery frame, whereby a detected portion indicative of a type of the embroidery frame. On the other hand, three detecting switches (microswitches) are provided at the carriage side so as to correspond to the detecting positions respectively. The detecting switches detect the respective concavo-convex patterns (presence or absence of projections at respective detecting positions), whereby the type of the attached embroidery frame is determined. This construction, however, requires three detecting switches, thereby complicating the structure for detecting the type of the embroidery frame. Additionally, since the type of the embroidery frame is detected after the embroidery frame has been attached, loss of time also occurs when a wrong embroidery pattern has been attached.

SUMMARY OF THE INVENTION

Therefore, an object of the present invention is to provide an embroidery sewing machine which has a function of detecting the type of a n embroidery frame and which can detect the type of the embroidery frame in a shorter period of time and can reduce the lost time in attachment of a wrong embroidery frame.

The present invention provides an embroidery sewing machine in which a workpiece cloth is moved so that an embroidery pattern is formed thereon, the embroidery sewing machine comprising a plurality of types of embroidery frames differing in a size and/or a shape from each other and holding the workpiece cloth, the embroidery frames being selectively used, a carriage, a moving mechanism moving the carriage independently in two directions perpendicular to each other, a frame holder to which the embroidery frames are selectively attached, the frame holder including a holder body fixed to the carriage and a movable holder mounted to one of a plurality of positions corresponding to the respective types of the embroidery frames relative to the holder body so that the position of the movable holder is exchangeable, a detector detecting a position of the movable holder relative to the holder body, and a determining unit determining the type of the embroidery frame based on a result of detection by the detector.

Before attaching a desired embroidery frame to the frame holder, the operator changes the position of the movable holder relative to the holder body of the frame holder corresponding to the type of the embroidery frame. The position of the movable holder is then detected by the detector, and the type of the embroidery frame is determined by the determining unit. In this case, since the type of the embroidery frame is detected before the embroidery frame is attached to the frame holder, the detection of the type of the embroidery frame can be carried out in a shorter period of time. Further, when a wrong embroidery frame is to be attached to the frame holder, an alarm can be given before attachment. This can save a time required to replace the attached embroidery frame by a correct one and a time required to change workpiece cloths.

In a preferred form, the detector includes a detected body provided with a plurality of detected portions corresponding to the embroidery frames respectively and a detecting element detecting the detected portion of the detected body. As a result, the arrangement of the detector can be simplified. In this case, the detected body is mounted on the movable holder and the detecting element is mounted on either the holder body or the carriage. Alternatively, the detected body is mounted on either the holder body or the carriage and the detecting element is mounted on the movable holder. In each case, the detector detects the detected portion of the detected body, so that the position of the movable holder relative to the holder body can reliably be detected. Further, when the detecting element is fixed to the carriage, the wiring arrangement from the detector can be simplified as compared with the case where the detector is provided at the movable holder side. Consequently, the wiring structure can be simplified.

In another preferred form, the detecting element includes a rotary potentiometer having a detecting member brought into contact with one of the detected portions of the detected body. The rotary potentiometer itself is relatively inexpensive and a single detector can detect a plurality of detected portions. Consequently, the detector can be simplified in the arrangement and rendered inexpensive.

In further another preferred form, the detected portions of the detected body have heights or widths differing from each other along a direction in which the movable holder is moved respectively. Alternatively, each detected portion of the detected body includes a tapered face having a height or a width changing therealong. In each case, the arrangement of the detected body can be simplified.

In further another preferred form, the holder body includes a guide mechanism guiding the movable holder to one of the positions by sliding movement and a positioning mechanism positioning the movable holder at the one of the positions. Consequently, the operator can easily displace the movable holder. Further, the movable holder can reliably be fixed to each position when the holder body includes a fixing mechanism fixing the movable holder positioned by the positioning mechanism to the holder body. In this case, the positions at which the movable holder is positioned by the positioning mechanism correspond to the detected portions of the detected body respectively.

As more concrete construction of the frame holder, each embroidery frame has both sides opposite to each other, and the frame holder is formed generally into a C-shape and includes a body fixed to the carriage and extending in one direction, the body of the frame holder having both ends, and two arms extending substantially perpendicularly from the ends of the body to support both sides of the embroidery frame respectively. In this case, the holder body of the frame holder includes the body and either one of the arms, and the movable holder includes the other arm mounted thereon so as to be displaceable relative to the body of the frame holder. Alternatively, each embroidery frame has both sides opposite to each other, and the frame holder is formed generally into a C-shape and includes a body fixed to the carriage and extending in one direction, the body of the frame holder having both ends, and two arms extending substantially perpendicularly from the ends of the body to support both sides of the embroidery frame respectively. In each case, the embroidery frame can be supported at two portions thereof, whereupon the embroidery frame can be moved with high rigidity.

BRIEF DESCRIPTION OF THE DRAWINGS

Other objects, features and advantages of the present invention will become clear upon reviewing the following description of the embodiment with reference to the accompanying drawings, in which:

FIG. 1

is a perspective view of the overall embroidery sewing machine in accordance with an embodiment of the present invention;

FIG. 2

is a plan view of a frame holder to which a largest embroidery frame is attached;

FIG. 3

is an enlarged plan view of the left latter half of the frame holder used in the embroidery sewing machine;

FIG. 4

is a plan view of the frame holder to which a third larger embroidery frame is attached;

FIG. 5

is a left side view of the latter half of the frame holder;

FIG. 6

is a schematically exploded perspective view of the left latter half of the frame holder;

FIG. 7

is a front view of a detector;

FIGS. 8A

to

8

E are front views of the detector and a detected body, showing operations of these components;

FIG. 9

is a block diagram showing a control unit; and

FIG. 10

is a perspective view of the detected body in a modified form.

DETAILED DESCRIPTION OF THE INVENTION

An embodiment of the present invention will be described with reference to

FIGS. 1

to

9

. In the embodiment, the invention will be applied to a multi-needle embroidery sewing machine which can perform an embroidery sewing using six embroidery threads and to which one of five embroidery frames having different sizes or sewing regions is attached. In the following description, the back-and-forth direction will be referred to as “the Y direction,” whereas the right-and-left direction as viewed from the operator will be referred to as “the X direction.”

Referring to

FIG. 1

, an overall construction of the multi-needle embroidery sewing machine M is shown. A support base

3

is placed on a mounting base (not shown) to support the embroidery sewing machine M. The support base

3

is formed generally into a U-shape and has an open front and includes a pillar

4

extending upward from a rear curved portion of the support base

3

. A sewing arm

1

extends frontward from an upper end of the pillar

4

. The arm

1

has a distal end on which a needle bar case

6

is mounted so as to be moved in the right-and-left direction (X direction). A cylindrical bed

2

is formed integrally with the support base

3

so as to extend frontward from the rear of the support base

3

. A thread loop taker and the like (not shown) is provided in an interior of a distal end of the cylinder bed

2

.

The needle bar case

6

includes, for example, six needle bars (none of them shown) and six thread take-up levers

15

both vertically movable. Sewing needles

13

are mounted to lower ends of the needle bars respectively. Only one of the sewing needles

13

is shown. A thread holder

16

is mounted on an upper part of the arm

1

. Six thread spools (not shown) are set on the thread holder

16

. Embroidery threads (needle threads) of six different colors are supplied via thread tension regulators

14

and thread take-up levers

15

to sewing needles

13

respectively. The thread holder

16

is switchable between a retracted position as shown in

FIG. 1 and a

position where the thread holder

16

is rearwardly spread generally into a V-shape.

The needle bar case

6

is moved in the X direction by a needle bar selecting mechanism (not shown) so that one of the needle bars to be driven is selected. Only the selected needle bar and corresponding thread take-up lever

15

are driven by a driving force transferred from a sewing machine motor

107

(see

FIG. 9

) provided in the pillar

4

via a needle bar vertically driving mechanism (not shown) provided in the arm

1

, so that the selected needle bar and corresponding thread take-up lever

15

are vertically driven. At this time, the needle bar vertically driving mechanism forms embroidery stitches in cooperation with a thread loop taker (not shown) also driven by the motor

107

using the selected embroidery thread of the selected color.

Three carriages

5

are mounted on the support bases

3

respectively. Each carriage

5

is located over the cylinder bed

2

and freely moved independently in the X and Y directions perpendicular to each other. A frame holder

8

is mounted on each carriage

5

. An embroidery frame

7

(see

FIGS. 2 and 4

) holding workpiece cloth is detachably attached to the frame holder

8

. An embroidery frame detector

9

(see

FIGS. 2

to

5

) is provided on the frame holder

8

for detecting a type of the embroidery frame

7

. The carriage

5

, frame holder

8

, embroidery frame

7

and embroidery frame detector

9

will be described in detail later.

An operation panel

11

on which the operator enters various input is provided on the right side of the arm

1

. The operation panel

11

includes a display

10

on which an image of embroidery pattern and the like is displayed. The operation panel

11

is displaceable (foldable) between a retracted position as shown in

FIG. 1 and a

use position where the display

10

is directed frontward.

The embroidery sewing machine M further comprises a control unit

100

(see

FIG. 9

) for controlling the overall embroidery sewing machine. Based on embroidery data and the like, the control unit

100

controls the sewing machine motor

107

, the needle bar selecting mechanism, the moving mechanism and the like, whereby an embroidery sewing operation is automatically carried out for the workpiece cloth held on the embroidery frame

7

.

The carriage

5

will now be described. The carriage

5

includes a Y-direction carriage

20

and an X-direction carriage

21

mounted on the Y-direction carriage

20

as shown in

FIGS. 2 and 4

. The Y-direction carriage

20

extends in the X direction over the left and right support bases

3

. The support bases

3

have guide grooves

22

formed in the upper sides so as to extend in the Y direction respectively. Only one of the guide grooves

22

is shown in FIG.

1

. Two legs

23

only one of which is shown are inserted into the guide grooves

22

respectively. Left and right ends of the Y-direction carriage

20

are coupled to the paired legs

23

respectively. Driving force of a Y-direction drive motor

110

is transmitted via a Y-direction driving force transferring mechanism to the legs

23

. Consequently, the Y-direction carriage

20

is moved freely in the Y direction.

The X-direction carriage

21

is formed into the shape of an oblong plate and includes a coupling member

32

provided in the front thereof as shown in

FIGS. 2 and 4

. The X-direction carriage

21

further includes a pair of engagement members

31

provided on the rear right and left ends thereof respectively. The engagement members

31

are in engagement with guide grooves

30

formed in the Y-direction carriage

20

so as to extend in the X direction respectively. The X-direction carriage

21

is connected at two positions by two connecting pins

29

respectively to an endless timing belt

27

as shown in

FIGS. 2 and 4

. The timing belt

27

extends between a pulley

25

and a driven pulley

26

. The pulley

25

is mounted on an output shaft of an X-direction driving motor

24

mounted on the left end of the Y-direction carriage

20

. The driven pulley

26

is mounted on the right end of the Y-direction carriage

20

. As the result of the aforesaid construction, the driving force of the X-direction driving motor

24

is transferred via the timing belt

27

to the X-direction carriage

21

, which is guided by a guide groove

30

thereby to be moved in the X direction within the Y-direction carriage

20

.

Thus, the Y-direction carriage

20

is moved freely in the Y direction relative to the support base

3

by the Y-direction driving motor

110

and the like, whereas the X-direction carriage

21

is moved freely in the X direction within the Y-direction carriage

20

by the X-direction driving motor

24

and the like. Consequently, the frame holder

8

coupled to the X-direction carriage

21

is moved freely in the X and Y directions.

The five types of embroidery frames

7

will be described. Each embroidery frame

7

includes an embroidery frame body (inner frame)

91

formed into the shape of a rectangular frame having rounded corners and an outer frame

92

detachably fitted with an outer periphery of the embroidery frame body

91

. Each embroidery frame

7

further includes a pair of arms

93

and

94

fixed to both opposite ends of the embroidery frame body

91

respectively. A piece of workpiece cloth is held between the embroidery frame body

91

and the outer frame

92

thereby to be held in a stretched state inside the embroidery frame body

91

. In this case, a generally rectangular sewing region

90

having a predetermined size is set inside the embroidery frame body

91

. The arms

93

and

94

are disposed so as to be symmetrical with each other about the center of the embroidery frame

7

. Each of the arms

93

and

94

has an engagement groove

95

and an engagement hole

96

for attachment of the embroidery frame

7

to the frame holder

8

.

The five types of embroidery frames

7

differ from one another in the size (shape) of an embroidery frame body

91

and accordingly have respective sewing regions

90

differing from one another in the size (shape) thereof. Further, the embroidery frames

7

inclusive of the respective arms

93

and

94

have different lateral dimensions or widths. The width of the embroidery frame becomes larger as the size of the embroidery frame body is increased. One of the embroidery frames

7

is selectively used according to the size of an embroidery frame to be formed (the size of the sewing region

90

), the size of workpiece cloth or the like.

FIG. 2

shows the largest embroidery frame

7

, whereas

FIG. 4

shows the third largest embroidery frame

7

. When each of the embroidery frames

7

need to be distinguished from each other in the following description, the largest one will be referred to as “embroidery frame

7

A”, whereas the third largest one will be referred to as “embroidery frame

7

B.”

The frame holder

8

will be described. The frame holder

8

includes a holder body

35

fixed to the coupling member

32

of the X-direction carriage

21

and a movable holder

36

mounted on the holder body

35

so as to be displaceable or movable, as shown in

FIGS. 2 and 4

. The frame holder

8

is thus formed into a C-shape and has a front opening. The movable holder

36

is slid by the guiding mechanism

38

thereby to be guided relative to the holder body

35

. Further, the movable holder

36

is positioned by a positioning mechanism

40

at one of five positions corresponding to the widths of the five embroidery frames

7

respectively. The movable holder

36

thus positioned is fixed to the holder body

35

by a fixing mechanism

39

.

The holder body

35

includes a main body

41

formed into the shape of an oblong plate and a right arm

42

extending forward substantially perpendicularly from a right end of the main body

41

as shown in

FIGS. 2 and 4

. The main body

41

is elongated in the X direction and has a downwardly bent front edge. The holder body

35

is thus generally formed into an L-shape. The main body

41

includes a central portion fixed by two small screws

43

and

44

to an upper face of the coupling member

32

of the X-direction carriage

21

. The right arm

42

has a distal end provided with an engaging pin

45

engaging an engagement groove

95

of the embroidery frame

7

. A leaf spring

46

is mounted on the right arm

42

so as to be located in the rear of the engaging pin

45

. The arms

93

and

94

of the embroidery frame

7

are adapted to be held between the leaf spring

46

and the right arm

42

when the embroidery frame

7

has been inserted from the front.

The movable holder

36

includes an oblong coupling portion

50

and a left arm

51

extending forward from a left end of the coupling portion

50

(substantially perpendicularly from the main body

41

) as shown in

FIGS. 2 and 4

. The coupling portion

50

and the left arm

51

are formed integrally with the movable holder

36

generally into an L-shape. The coupling portion

50

is adapted to be coupled to an upper face of the main body

41

. The left arm

51

is disposed opposite the right arm and includes an engaging pin

54

engaging the engagement hole

96

of the embroidery frame

7

and a leaf spring

55

. The arms

93

and

94

of the embroidery frame

7

are adapted to be held between the leaf spring

55

and the left arm

51

when the embroidery frame

7

has been inserted from the front. Accordingly, the left and right arms

93

and

94

of the embroidery frame

7

are supported on the left and right arms

51

and

42

respectively.

The coupling portion

50

has a rising wall

52

extending from the central portion to the right end thereof as shown in

FIGS. 5 and 6

. The rising wall

52

has an upper end provided with a rearwardly bent attachment portion

53

. A detected body

80

is attached to the underside of the attachment portion

53

as will be described later.

An auxiliary plate

37

is attached to the underside of the holder body

35

so as to hold the holder body

35

between itself and the movable holder

36

as shown in

FIGS. 5 and 6

. The auxiliary plate

37

is formed into a rectangular shape and has left and right ends formed with a pair of screw holes

67

and

68

with which thread portions

65

a

and

66

a

of the fixing mechanism

39

are threadedly engaged respectively as shown in FIG.

6

. Two guide pins

61

a

and

61

b

are formed on the upper side of the auxiliary plate

37

so as to be located inside the screw holes

67

and

68

respectively.

The guiding mechanism

38

is constructed as follows. The main body

41

of the holder body

35

has a first guide groove

60

extending in the X direction from the left end to the central portion thereof as shown in FIG.

6

. The paired guide pins

61

a

and

61

b

are inserted through the first guide groove

60

. The guide pins

61

a

and

61

b

have distal ends which are inserted into a pair of pin holes

63

a

and

63

b

formed in the left end of the movable holder

36

respectively. The coupling portion

50

of the movable holder

36

has a second guide groove

62

extending in the X direction from the central portion to the right end thereof. The holder body

35

has a pin hole

43

a

formed therein to the right of the first guide groove

60

. A small screw

43

is inserted through the second guide groove

62

and the pin hole

43

a

to be engaged with a screw hole (not shown) of the coupling member

32

. Accordingly, the guide pins

61

a

and

61

b

fitted in the respective pin holes

63

a

and

63

b

are guided along the first guide groove

60

, and the small screw

43

is guided along the second guide groove

62

. As a result, the movable holder

36

and accordingly the auxiliary plate

37

are guided in the right-and-left direction relative to the holder body

35

. The guiding mechanism

38

is thus constructed.

The fixing mechanism

39

includes a pair of fixing knobs

65

and

66

having lower ends formed with threaded portions

65

a

and

66

a

respectively as shown in FIG.

6

. The movable holder

36

has two pin holes

69

a

and

69

b

. The threaded portions

65

a

and

66

a

of the fixing knobs

65

and

66

are inserted through pin holes

69

a

and

69

b

and the first guide groove

60

of the holder body

35

to be engaged with screw holes

67

and

68

of the auxiliary plate

37

. When the fixing knobs

65

and

66

are located so as to be directed frontward as shown by solid line in

FIGS. 2 and 3

, the holder body

35

is held tightly between the moving holder

36

and the auxiliary plate

37

, whereby the movable holder

36

is fixed to the holder body

35

. On the other hand, threaded engagement of the screws

65

a

and

66

a

with the respective screw holes

67

and

68

is loosened when the fixing knobs

65

and

66

are turned clockwise as shown by two-dot chain line in

FIGS. 2 and 3

to be changed to positions where the fixing knobs

65

and

66

are directed obliquely leftward. Consequently, the movable holder

36

can be slid in the X direction relative to the holder body

35

.

The positioning mechanism

40

includes a positioning member

71

having a front end mounted to the movable holder

36

and five positioning holes

74

a

to

74

e

formed in the holder body

35

so as to be located in front of the first guide groove

60

, as shown in FIG.

6

. The positioning member

71

has a semispherical engagement convexity

71

b

formed on a rear end of a leaf spring

71

a

so as to project downward. The engagement convexity

71

b

is inserted through an insertion hole

73

formed through the movable holder

36

, projecting from the underside of the movable holder

36

to be engaged with any one of the positioning holes

74

a

to

74

e

. The positioning holes

74

a

to

74

e

are formed so as to correspond to the widths of the five embroidery frames

7

. With slide of the movable holder

36

in the X direction, the engagement convexity

71

b

of the positioning member

71

is disengaged from one of the positioning holes

74

a

to

74

e

and slightly brought up against the spring force of the leaf spring

71

a

. Consequently, the engagement convexity

71

b

is moved while sliding on the upper side of the holder body

35

(between the positioning holes

74

a

to

74

e

). When the engagement convexity

71

b

corresponds with the subsequent one of the positioning holes

74

a

to

74

e

, the spring force engages the engagement convexity

71

b

with that positioning hole. This provides clicking. As a result, the movable holder

36

is positioned and fixed at any one of five positions having different distances between the right arm

42

and them by the positioning mechanism

40

. One of the five embroidery frames

7

is attachable when the movable holder

36

is positioned at any one of the positions.

For example, when the engagement convexity

71

b

is in engagement with the leftmost positioning hole

74

a

, the movable holder

36

is mounted to assume the leftmost position, whereupon the largest embroidery frame

7

A can be attached to the frame holder

8

, as shown in

FIGS. 2 and 3

. In this state, the movable holder

36

is released from the fixing by the fixing mechanism

39

and then moved by the positioning mechanism

40

to a position corresponding to the third positioning hole

74

c

while being guided rightward by the guiding mechanism

38

. Subsequently, the movable holder

36

is fixed by the fixing mechanism

39

again. Thus, the third largest embroidery frame

7

B can be attached to the frame holder

8

as shown in FIG.

4

.

In attaching the embroidery frame

7

to the frame holder

8

, the operator puts both arms

93

and

94

of the embroidery frame

7

between the leaf springs

46

and

55

and the right and left arms

42

and

51

, inserting the arms

93

and

94

while the front portion of the embroidery frame

7

is inclined slightly upward. The embroidery frame

7

is then returned to the horizontal state and the engaging pin

54

of the left arm

51

is engaged with the engagement hole

96

of the arm

93

, whereas the engaging pin

45

of the right arm

42

is engaged with the engagement groove

95

of the arm

94

. As a result, the embroidery frame

7

is supported at two points by the frame holder B. Since the arms

93

and

94

have the same structure, the embroidery frame

7

may be attached to the frame holder

8

in the reversed state.

The embroidery frame detector

9

for detecting the five types of embroidery frames

7

will now be described. The embroidery frame detector

9

includes a detected body

80

made from a synthetic material and attached to the underside of the attachment portion

53

of the movable holder

36

and a detecting element

83

mounted on the coupling member

32

of the X-direction carriage

21

. The detected body

80

is formed into the shape of a square bar elongated in the X direction and has an underside becoming higher stepwise from a right end to a left end so as to correspond to five positions, whereby five detected portions

82

a

to

82

e

are formed, as shown in

FIGS. 6 and 8A

to

8

E. Spaces between centers of detected portions

82

a

to

82

e

adjacent to each other are approximately the same as spaces between the positioning holes

74

a

to

74

e

of the positioning mechanism

40

.

In the embodiment, the detecting element

83

comprises a rotary potentiometer having a detecting member

84

projecting frontward as shown in FIG.

7

. The detecting member

84

is adapted to be brought into contact with any one of the detected portions

82

a

to

82

e

. The detecting member

84

is biased clockwise about a shaft

85

by a coil spring incorporated in the detecting element

83

. A variable resistor incorporated in the detecting element

83

varies its resistance value as the detecting member

84

is rotated about the shaft

85

. When supplied with a predetermined voltage, the detecting element

83

delivers an output signal which is indicative of the changes in the resistance value depending upon a rotational position of the detecting member

84

or changes in the current value with the changes in the resistance value. A stopper

86

is mounted on the coupling member

32

so as to protrude frontward. Even when brought out of contact with the detected portions

82

a

to

82

e

, the detecting member

84

is stopped by the stopper after having been turned by a predetermined angle. Wiring

87

from the detecting element

83

is drawn upward.

FIGS. 8A

to

8

E illustrate a manner of detecting the type of the embroidery frame

7

by the embroidery frame detector

9

. When the movable holder

36

is moved in the right-and-left direction, the detected body

80

attached to the movable holder

36

is also moved with the latter. Accordingly, the detecting member

84

of the detecting element

83

is turned about the shaft

85

when brought into contact with any one of the detected portions

82

a

to

82

e

formed on the detected body

80

. When the movable holder

36

is positioned at a desired position by the positioning mechanism

40

, the detecting member

84

of the detecting element

83

is brought into contact with any one of the detected portions

82

a

to

82

e

corresponding to the determined position. In this case, when the detecting member

84

is in contact with any one of the detected portions

82

a

to

82

e

, the detecting element

83

delivers an output signal with any one of current values I

1

to I

5

. Accordingly, the detecting element

83

detects any one of detected portions

82

a

to

82

e

corresponding to the position of the movable holder

36

, whereupon the type of the embroidery frame

7

to be attached to the frame holder

8

can be detected indirectly.

For example, in order that the largest embroidery frame

7

A may be attached, the engagement convexity

71

b

is engaged with the positioning hole

74

a

so that the movable holder

36

is fixed, as shown in FIG.

2

. The detecting member

84

is then brought into contact with the detected portion

82

a

, so that the embroidery frame

7

(

7

A) to be attached is detected, as shown in FIG.

8

A. Further, in order that the third largest embroidery frame

7

B may be attached, the engagement convexity

71

b

is engaged with the positioning hole

74

c

so that the movable holder

36

is fixed, as shown in FIG.

4

. The detecting member

84

is then brought into contact with the detected portion

82

c

, so that the embroidery frame

7

B to be attached is detected, as shown in FIG.

8

C.

The type of each of the other embroidery frames is detected in the same manner as described above. More specifically, when the engagement convexity

71

b

is in engagement with the positioning hole

74

b

, the detecting member

84

is brought into contact with the detected portion

82

b

as shown in FIG.

8

B. When the engagement convexity

71

b

is in engagement with the positioning hole

74

d

, the detecting member

84

is brought into contact with the detected portion

82

d

as shown in FIG.

8

D. When the engagement convexity

71

b

is in engagement with the positioning hole

74

e

, the detecting member

84

is brought into contact with the detected portion

82

e

as shown in FIG.

8

E. Consequently, the embroidery frame

7

to be attached can be detected in each of the above-described cases.

A control unit

100

will now be described. The control unit

100

controls the overall operation of the embroidery sewing machine M. Referring to

FIG. 9

, the control unit

100

comprises a computer

101

and an input-output interface

106

via which signals are supplied into and delivered from the computer

101

. The computer

101

includes CPU

102

, ROM

103

, RAM

104

and a bus

105

connecting the former components to one another. To the input-output interface

106

are connected a drive circuit

108

for the sewing machine motor

107

, a drive circuit

109

for the X-direction drive motor

24

, a drive circuit

111

for the Y-direction drive motor

110

and the like. The detecting element

83

and the operation panel

11

are also connected to the input-output interface

106

. ROM

103

stores an embroidery frame type determining program for determining the type of the embroidery frame

7

, embroidery data used for execution of an embroidery sewing operation and the like. RAM

104

stores various data such as data of current values read from the detecting element

83

and the like. The aforesaid embroidery data includes data indicative of a needle location for every stitch relative to workpiece cloth (or movement amounts of the embroidery frame

7

in the X and Y directions) and the like. The control unit

100

controls the sewing machine motor

107

and the moving mechanism (the X direction drive motor

24

and the Y direction drive motor

110

) based on the embroidery data, so that the carriage

5

and accordingly the embroidery frame

7

supported on the frame holder

8

are moved in the X and Y directions, whereby an embroidery forming operation is carried out on the workpiece cloth.

An embroidery frame type determining program will be described. The control unit

100

determines a type of the embroidery frame

7

to be attached based on the signal delivered from the detecting element

83

and the embroidery frame type determining program. In order that a desired embroidery frame

7

may be attached, the movable holder

36

is positioned at a predetermined position and fixed by the positioning mechanism

40

. The detecting member

84

of the detecting element

83

is then brought into contact with any one of the detected portions

82

a

to

82

e

of the detected body

80

corresponding to the position of the movable holder

36

to be held in the state. The resistance value of the detecting element

83

varies according to a rotational angle of the held detecting member

84

. An output signal (one of current values I

1

to I

5

) according to the resistance value is supplied to the control unit

100

. The control unit

100

determines the embroidery frame

7

to be attached based on the supplied output signal. Accordingly, the control unit

100

serves as a determining unit.

For example, when the engagement convexity

71

b

is in engagement with the positioning hole

74

a

, the control unit

100

reads the current value I

1

and the embroidery frame

7

A is determined as shown in FIG.

2

. Further, when the engagement convexity

71

b

is in engagement with the positioning hole

74

c

, the control unit

100

reads the current value I

3

and the embroidery frame

7

B is determined as shown in FIG.

4

. When the embroidery frame

7

to be attached does not correspond to the size of embroidery data selected by the operator, the control unit

100

having determined the type of the embroidery frame

7

displays an alarm message on the display

10

of the operation panel

11

or produces alarming sound to inform the operator that the embroidery frame

7

is unsuitable.

The following effects can be achieved from the above-described embroidery sewing machine. The embroidery frame

7

is supported on the frame holder

8

mounted on the carriage

5

in the foregoing embodiment. On this occasion, the position of the movable holder

36

relative to the holder body

35

of the frame holder

8

is changed according to the type of the embroidery frame

7

, and the embroidery frame detector

9

is provided for detecting the position of the movable holder

36

. Accordingly, when the movable holder

36

is just positioned so as to correspond to a desired embroidery frame

7

, the position of the movable holder

36

is detected by the embroidery frame detector

9

, whereby the type of the embroidery frame

7

to be attached is determined. Consequently, since the type of the embroidery frame

7

is determined before attached to the frame holder

8

, the detection of the type of the embroidery frame

7

can be carried out in a short period of time.

Further, when the operator is attaching a wrong embroidery frame

7

, an alarming operation can be carried out before the wrong embroidery frame

7

is attached. Consequently, a wrong embroidery frame

7

not corresponding to the embroidery data can be prevented from being attached. This can save a period of time required to replace the attached embroidery frame

7

by a correct one and a period of time required to detach the workpiece cloth from one embroidery frame and re-attach it to another one.

The embroidery frame detector

9

includes the detecting element

83

comprising the relatively inexpensive rotary potentiometer and the single detected body

80

having the five detected portions

82

a

to

82

e

. As a result, the construction and arrangement of the detecting element

83

can be simplified and the detecting element

83

can be produced at low costs. The detected body

80

can also be simplified. Consequently, the overall embroidery frame detector

9

can be simplified. Further, since the detecting element

83

is disposed at the carriage

5

side, the wiring arrangement from the detecting element

83

can be simplified as compared with the case where the detecting element is disposed at the movable holder

36

side. Additionally, the frame holder

8

is provided with the guiding mechanism

38

for changing the position of the movable holder

36

, the fixing mechanism

39

and the positioning mechanism

40

. Consequently, the operator can change the position of the movable holder

36

readily and reliably.

The invention should not be limited to the foregoing embodiment. The embodiment can be modified or expanded as follows. In the foregoing embodiment, the detected body

80

is attached to the attachment portion

53

of the movable holder

36

so that the detected portions

82

a

to

82

e

are located higher and higher from the right to the left. However, the detected body

80

may be attached to the attachment portion

53

so that the detected portions

82

a

to

82

e

are directed in the back-and-forth direction, instead. In this case, the detecting member

84

of the detecting element

83

may be attached so as to be brought into contact with the detected portions

82

a

to

82

e

. Accordingly, the difference in the width of the detected body

80

is detected by the detecting element

83

, whereby the type of the embroidery frame

7

is determined.

In the foregoing embodiment, the detected body

80

is formed with five detected portions

82

a

to

82

e

located higher and higher from the right to the left so as to correspond to the embroidery frames

7

respectively. However, the detected body

80

A may be made of a tapered member without the stepped portions of the detected portions

82

a

to

82

e

and a tapered face of the tapered member may serve as a plurality of detected portions, as shown in

FIG. 10

, instead. When the detected body

80

A is constructed as described above, a range of value of current from the detecting element

83

is previously set so as to correspond to the size of the embroidery frame, so that the type of the embroidery frame

7

is detected according to the current value. In this arrangement, too, the detected portion

81

may be directed in any direction.

Only the flat embroidery frames

7

can be attached in the foregoing embodiment. However, a cap frame used to form embroidery on a peripheral portion of a cap may be attachable. In this case, too, it is desirable that the cap frame can also be detected by the detecting element such as the potentiometer.

The invention is applied to a multi-needle embroidery sewing machine M in the foregoing embodiment. However, the invention may be applied to any type embroidery sewing machine to which a plurality of embroidery frames are attachable, such as single needle embroidery sewing machines.

The operator manually changes the position of the movable holder

36

in the foregoing embodiment. However, the invention may be applied to an embroidery sewing machine in which the position of the movable holder is automatically changed on the basis of image data or the like selected on the operation panel.

The holder body

35

comprises the body

41

and the right arm

42

in the foregoing embodiment. However, the holder body may comprise only the body

41

, and the left and right arms

51

and

42

serving as movable holders may be mounted on the holder body so as to be displaceable.

The detecting element

83

is attached to the carriage

5

(the X direction carriage

21

) in the foregoing embodiment. However, the detecting element

83

may be attached to the holder body if the detected portion of the detected body is detectable.

The detected body

80

is attached to the movable holder

36

and the detecting element

83

is attached to the carriage

5

in the foregoing embodiment. However, the detected body may be attached to the carriage or the holder body, whereas the detecting element may be attached to the movable holder, instead.

The foregoing description and drawings are merely illustrative of the principles of the present invention and are not to be construed in a limiting sense. Various changes and modifications will become apparent to those of ordinary skill in the art. All such changes and modifications are seen to fall within the scope of the invention as defined by the appended claims.

Number	Name	Date	Kind
4763586	Takenoya et al.	Aug 1988	A
6568337	Durville	May 2003	B1

Number	Date	Country
A 6-319880	Nov 1994	JP
A 2002-52283	Feb 2002	JP

Embroidery sewing machine with embroidery frame type detecting function

Information

Patent Number

Date Filed

Date Issued

Inventors

Original Assignees

Examiners

Agents

CPC

US Classifications

Field of Search

US

International Classifications

Abstract

Description

Claims

Priority Claims (1)

US Referenced Citations (2)

Foreign Referenced Citations (2)