JP2960363B2 - Bobbin case - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bobbin case having a full rotation kettle, and more particularly to a structure for guiding a lower thread drawn from an end wall of a bobbin case to a lower thread tension spring.

[0002]

2. Description of the Related Art FIG. 8 is a perspective view of a bobbin case 1, a bobbin 2 and an inner hook 3 showing a typical prior art. An outer hook (not shown) that is driven to rotate about a horizontal rotation axis is accommodated in a state where an inner hook 3 having a rail 4 formed on an outer peripheral surface thereof is prevented from rotating, and a bobbin case 1 is accommodated in the inner hook 4. The bobbin case 1 houses the bobbin 2 around which the bobbin thread 5 is wound.

The bobbin case 1 has a substantially C-shaped peripheral wall 6 opened upward in FIG. 8, an end wall 7 for closing one end of the peripheral wall 6 in the axial direction, and a slidable one-diameter line direction on the end wall 7. And an operation piece 9 for displacing the latch 8 in the one diameter line direction. On the peripheral wall 6, the bobbin case 1
A lower thread fitting hole 10 which is a lower thread fitting recess into which the lower thread 5 of the bobbin 2 housed therein is inserted as shown by a virtual line 5a in FIG. And a lower thread insertion hole 11 extending from the lower thread fitting hole 10 to the lower end of the lower thread tension spring 12. A spring fitting hole 14 into which the part 13 is partially fitted is formed. A part of the free end portion 13 of the lower thread tension spring 12 that fits into the spring fitting hole 14 is bent inward in the radial direction, whereby the lower thread tension spring 12 and the outer peripheral surface of the peripheral wall 6 are Bobbin thread 5 drawn out from between as shown by virtual line 5a
However, it is prevented from getting out from between the lower thread tension spring 12 and the outer peripheral surface of the peripheral wall 6.

The base end 15 of the lower thread tension spring 12 is fixed to the peripheral wall 6 by a bolt 16, and the pressing force of the lower thread tension spring 12 against the outer peripheral surface of the peripheral wall 6 is changed by another adjusting bolt 17. The tension of the lower thread 5 pulled out from the bobbin case 1 can be adjusted.

The bobbin 2 housed in the bobbin case 1 has a pair of flanges 21a and 21b,
1a and 21b. Further, the inner hook 3 has a peripheral wall 23 on which the rail 4 is formed.
And a bottom 24 extending in one diameter direction at one axial end of the peripheral wall 23, and a stud 25 erected on the bottom 24 toward the open end. An annular fitting recess 26 is formed at the free end of the stud 25.

The end wall 7 of the bobbin case 1 also has a peripheral wall 6
The stud 25 is inserted into the cylindrical portion 27 while the bobbin case 1 is mounted on the inner hook 3, and is formed on the end wall 7. Projecting outward from the central hole 28 formed, and passing through a first through hole 29 formed in the latch 8 to partially fit into a second through hole 30 formed in the operation piece 9 and exposed to the outside. doing. In such a state, the periphery of the latch 8 facing the first through hole 29 is fitted into the fitting recess 26 of the stud 25, and the bobbin case 1 is thus prevented from falling out of the inner hook 3.
The lower thread 5 of the bobbin 2 stored in the bobbin case 1 is drawn out through the space between the lower thread tension spring 12 and the outer peripheral surface of the peripheral wall 6 as shown by a virtual line 5a as described above. It is configured so that sewing can be performed with a preferable tension.

[0007]

In such a conventional technique, the bobbin thread 5 is wound around the bobbin 2, so that each of the flanges 21a and 21b is moved from the winding drum 22 to each of the flanges 21.
Since only the bobbin 2 can be wound in a range extending between the outer peripheral portions of the a and 21b and the amount of sewing by one bobbin 2 is limited, only the lower thread is wound without using the bobbin 2 as shown in FIG.
The bobbin 31 shown in FIG. In order to take out the lower thread 5 without rotating the winding bobbin 31 in the bobbin case 1, the lower thread 5 is pulled out from the center. For this reason, in the bobbin case 1 shown in FIG. 8, the bobbin thread 5 pulled out from the center of the bobbin 31 is sandwiched between the outer peripheral surface of the bobbin 31 and the inner peripheral surface of the peripheral wall 6 of the bobbin case 1. As a result, undesired tension other than the tension caused by the lower thread tension spring 12 is generated. Therefore, a bobbin case that can easily mount the lower thread between the peripheral wall and the lower thread tension spring is desired regardless of whether the bobbin 31 or the bobbin 2 is used.

[0008] Accordingly, an object of the present invention is to provide a bobbin case that can easily take out a bobbin thread regardless of whether it is a bobbin or a winding bobbin.

[0009]

The present invention according to claim 1 has a peripheral wall and an end wall for closing one end in the axial direction of the peripheral wall, and a bobbin thread is fitted on the peripheral wall. A lower thread tension spring is provided for forming a mating concave portion and resiliently contacting the outer peripheral surface of the peripheral wall to close the lower thread fitting concave portion. A hole is formed, and on the peripheral wall,
A first lower thread guide groove into which the lower thread is fitted from the peripheral edge of the end wall to the lower thread fitting recess is formed, and the lower thread takeout hole is
A latch formed at a center portion including the center axis of the end wall and having a first through hole communicating with the lower thread take-out hole formed at the center portion is formed on the end wall at one diameter line of the bobbin case. One end in the longitudinal direction along the lower thread guide groove is provided so as to be displaceable in a direction approaching / separating from the lower thread guide groove on the one diameter line, and the latch is provided in the first through hole in a state of being stacked on the latch. An operation piece having a communicating second through-hole is connected to one end in the longitudinal direction so as to be angularly displaceable, and a first through-hole and a first lower thread are provided on an outer surface of the latch facing the operation piece. A second lower thread guide groove extending between the guide grooves is formed, and the operation piece communicates between the second through hole and the outer surface on one side in the width direction perpendicular to the longitudinal direction of the operation piece. A thread insertion hole is formed, and the lower thread insertion hole faces the latch from the outer surface of the operation piece. As it becomes the inner surface near a bobbin case, characterized in that it is formed to be inclined in the direction toward the second lower yarn guiding groove of the latch. According to the present invention, in a bobbin case having a peripheral wall and an end wall, a lower thread is stored in a state of being wound around a bobbin or in a state of a winding bobbin, and a lower thread take-out hole formed in the end wall. Thus, the bobbin thread in the bobbin case can be pulled out of the bobbin case from the central portion of the bobbin or the bobbin bobbin. The bobbin thread thus taken out from the end wall of the bobbin case through the bobbin thread take-out hole fits into the bobbin thread guide groove formed in the peripheral wall, and in this state, the bobbin thread is moved to the outer periphery of the peripheral wall. The lower thread is inserted into the lower thread guide groove and the lower thread fitting recess by guiding the lower thread to the lower thread fitting recess by inserting the lower thread into the lower thread fitting recess along the surface. The lower thread is returned to the free end side of the lower thread tension spring again by disposing the lower thread to the free end side of the lower thread tension spring, so that the lower thread extends from the fitting recess to the free end of the lower thread tension spring. Can be elastically pressed by the lower thread tension spring. The bobbin thread thus taken out from the bobbin thread take-out hole of the end wall of the bobbin case is easily interposed between the bobbin thread tension spring and the outer peripheral surface of the peripheral wall to stabilize the bobbin thread on the bobbin thread path. In this state, the lower thread can be pulled out with a desired tension.
The bobbin case is provided with a latch and an operation piece for displacing the latch. The latch has a first through hole, and a first through hole and an outer surface facing the operation piece. A second lower thread guide groove extending between the lower thread guide grooves is formed. The lower thread drawn out from the lower thread take-out hole of the end wall fits into the second lower thread guide groove between the latch and the operation piece, and can be guided to the lower thread guide groove. In addition, it is possible to prevent the lower thread from being sandwiched between the latch and the operation piece and to generate an undesirably large tension, and to supply the lower thread smoothly. Further, in the operation piece,
Since the lower thread insertion hole is formed between the second through hole and the outer peripheral surface of the operation piece, the lower thread inserted through the lower thread take-out hole and drawn out from the first and second through holes to the lower thread is removed. The lower thread can be inserted only by inserting it into the insertion hole and pulling it into the second lower thread guide groove. With this, the lower thread is angularly displaced in the direction away from the latch, and the lower thread is inserted into the lower thread insertion hole and the second lower thread guide hole. 1
There is no need to pull out the through-hole, so that the operation piece is inserted in the lower thread insertion hole while being arranged substantially parallel to the latch, and is pulled so as to be interposed between the latch and the operation piece. Thereby, since it is possible to insert the lower thread into the second lower thread guide groove, no labor is required to fit the lower thread into the second lower thread guide groove, and the workability can be remarkably improved. . Moreover, the lower thread insertion hole is formed so as to be inclined in a direction approaching the second lower thread guide groove of the latch from the outer surface of the operation piece toward the inner surface facing the latch. The lower thread can be guided to the second lower thread guide groove of the latch without being lifted, and the work of mounting the lower thread in the second lower thread guide groove can be easily performed.

According to a second aspect of the present invention, the free end of the lower thread tension spring is formed to be bent in a direction away from the outer peripheral surface of the peripheral wall. According to the present invention, since the free end of the lower thread tension spring is bent in a direction away from the outer peripheral surface of the peripheral wall, the lower thread pulled out from the lower thread take-out hole of the end wall is guided to the lower thread guide groove. Can be easily inserted under the lower thread tension spring from a gap formed between the free end of the lower thread tension spring and the outer peripheral surface of the peripheral wall,
The mounting operation of the lower thread tension spring of the lower thread can be easily performed.

[0011]

[0012]

[0013]

FIG. 1 is a perspective view of a bobbin case 41 showing an embodiment of the present invention. The bobbin case 41 detachably attached to the inner rotary hook (see FIG. 8) has a substantially C-shaped peripheral wall 42 divided in the circumferential direction, and an end wall for closing one end of the peripheral wall 42 in the axial direction. 43. Such a bobbin case 41 is made of steel or stainless steel. A lower thread fitting recess 45 into which the lower thread 44 is fitted is formed in the peripheral wall 42 by being inserted in the thickness direction of the peripheral wall 42, and the lower thread is elastically brought into contact with an outer peripheral surface 46 of the peripheral wall 42. Lower thread tension spring 4 for closing thread fitting recess 45
7 are provided. The base end portion 48 of the lower thread tension spring 47
Is fixed to the peripheral wall 42 by a fixing bolt 49, and the peripheral wall 42 on the free end portion 51 side is adjusted by an adjustment bolt 50.
It is configured to be able to adjust the pressing force to the pressure.

A lower thread take-out hole 52 through which the lower thread 44 is inserted is formed in the end wall 43 at a central portion including the central axis of the peripheral wall 42 and the end wall 43. The lower thread 44 pulled out of the bobbin case 51 from the lower thread take-out hole 52 fits into the lower thread guide groove 53 formed in the peripheral wall 42 and is guided to the lower thread fitting recess 45. . By providing such a lower thread guide groove 53, the lower thread 44 is attached to the lower thread tension spring 47 and the peripheral wall 42 by tension or slack acting on the lower thread 44.
Is prevented from slipping out from between the outer peripheral surface 46 and the outer peripheral surface 46. A latch 55 in which a first through hole 54 communicating with the lower thread take-out hole 52 is formed at the end wall 43 has one end in the longitudinal direction close to the lower thread guide groove 53 on one diameter line of the bobbin case 41. The latch 55 is provided with an operation piece 57 having a second through-hole 56 communicating with the first through-hole 54 in a state where the second through-hole 56 is communicated with the first through-hole 54 in a state of being stacked on the latch. The latch 55 is connected so as to be angularly displaceable in the directions of arrows C1 and C2 with the vicinity of one longitudinal end of the latch 55 as the center of angular displacement. The peripheral wall 42 and the end wall 43 form a substantially cylindrical bobbin case main body 58 with a bottom, and the bobbin case main body 58, the lower thread tension spring 47, the latch 55, the operation piece 57, To form the bobbin case 41.

FIG. 2 is an exploded perspective view showing a state where the lower thread tension spring 47 is removed from the bobbin case main body 58. The free end portion 51 of the lower thread tension spring 47 has
Is attached to the peripheral wall 42, and the angle θ1 is set in a direction away from the outer peripheral surface 46 toward the upstream side in the outer hook rotating direction A.
The lower thread insertion portion 59 is formed so as to be inclined, and a lower thread removal portion 60 is formed on the end wall 43 side and bent inward at a substantially right angle in the radial direction. A lower thread tension spring 47 is provided on the side of the peripheral wall 42 on the base end 48 side of the lower thread removal portion 60.
The lower thread guide surface 61 is formed so as to be inclined at an angle θ2 from the base end portion 48 toward the free end portion 51 toward the inner side in the radial direction in the state of being attached to the lower thread guide surface 61. The angle θ1 is a lower thread 4 having a diameter of about 0.2 to 0.5 mm at its tip.
The angle at which 4 can be inserted is selected, for example, 3 to 10 degrees.
The angle θ2 of the lower thread guide surface 61 is selected to be 5 to 30 degrees.

The peripheral wall 42 also includes the lower thread pull-out preventing portion 6.
A groove 62 into which 0 is fitted is formed to extend in the circumferential direction.
In this way, the lower end of the lower thread tension spring 47 is formed at the free end portion 51 with the lower thread guide portion 61 having the lower thread guide surface 61, so that the lower thread 44 is pulled from the lower thread guide groove 53 to the corner 80. In the hooked state, it is guided to the free end portion 51 side, interposed between the outer peripheral surface 46 and the lower thread insertion portion 59, and further, the lower thread 44 is rotated in the direction of arrow E and pulled toward the base end portion 48 side. When the lower thread 44 is moved along the lower thread guide surface 61 as shown by arrow D in FIG.
The lower end of the free end portion 5 can pass through the lower thread insertion portion 59 and the outer peripheral surface 46 of the peripheral wall 42 as described above.
It can be interposed between the contact portion 63 between the base 1 and the base end portion 48 and the outer peripheral surface 46 of the peripheral wall 42. The lower thread 44
Is disposed in a state of being fitted into the lower thread guide groove 53 and the lower thread fitting concave portion 45 so as to be covered by the lower thread tension spring 47 from the outside, and the lower thread 44 is again loosened. By pulling back to the end portion 51 side, the lower thread 44 is arranged on the outer peripheral surface 46 of the peripheral wall 42 from the lower thread fitting concave portion 45 to the free end portion 51 of the lower thread tension spring 47, and is resilient by the lower thread tension spring 47. It can be pressed spontaneously. At this time, the lower thread 4
4, the lower thread 44 is not pressed by the contact portion 63 on the outer peripheral surface 46 of the peripheral wall 42 because the lower thread 4 is fitted into the lower thread guide groove 53 and the lower thread fitting recess 54, and therefore the lower thread The tension at 44 does not undesirably change during sewing, and a high-quality seam can be formed. Since the bobbin case 41 accommodates the bobbin bobbin (see FIG. 9), the tubular portion 27 is not formed as in the conventional bobbin case 1 shown in FIG.

FIG. 3 is a perspective view showing the latch 55.
As described above, the first through hole 54 is formed in the latch 55. A second lower thread guide groove 68 extending linearly between the first through hole 54 and the lower thread guide groove 53 is formed on an outer surface 67 of the latch 55 facing the operation piece 57. The second lower thread guide groove 68 causes the lower thread 44 to be sandwiched between the latch 55 and the operation piece 57 in a state where the latch 55 and the operation piece 57 are stacked and arranged substantially in parallel. Therefore, the lower thread 44 can be smoothly guided to the lower thread guide groove 53 of the peripheral wall 42 without generating an undesired tension or slack.

FIG. 4 is a perspective view showing the operation piece 57.
As described above, the second through hole 56 is formed in the operation piece 57. The operation piece 57 has a lower thread insertion hole 70 communicating between the second through hole 56 and the outer surface 69 of the operation piece 57.
Is formed.

FIG. 5 is an enlarged sectional view taken along section line VV of FIG. 4, FIG. 6 is an enlarged sectional view taken along section line VI-VI of FIG. 4, and FIG. FIG. 5 is an enlarged view showing the vicinity of an insertion hole. In this embodiment, the lower thread insertion hole 70 is parallel to the second lower thread guide groove 68 at an angle θ3 with respect to the longitudinal direction of the operation piece 57, and faces the latch 55 from the outer surface 71. The lower bobbin guide groove 6 of the latch 55 in the stacked state
8 and is inclined at an angle θ4 in a direction approaching the reference numeral 8. The angle θ3 is selected, for example, from 30 to 60 degrees, and the angle θ4 is selected, for example, from 45 to 60 degrees. Thereby, the lower thread 44 drawn out from the bobbin case 41 through the lower thread take-out hole 52, the first through-hole 54, and the second through-hole 56 is fitted into the lower thread insertion hole 70 and pushed in. It can be easily guided to the second lower thread guide groove 68.
Therefore, the direction C in which the operation piece 57 is separated from the latch 55
1 (see FIG. 1), there is no need to insert the lower thread between the operation piece 57 and the latch 55 and fit the lower thread into the second lower thread guide groove 68, 2 lower thread guide groove 6
8 can be easily carried out.

[0020]

According to the first aspect of the present invention, the bobbin case having the peripheral wall and the end wall is accommodated in a state in which the lower thread is wound around the bobbin or in a state of the winding bobbin.
Drawn out from the lower thread take-out hole formed in the end wall,
This allows the bobbin thread in the bobbin case to be drawn out of the bobbin case from the central portion of either the bobbin or the bobbin bobbin. The bobbin thread thus taken out from the end wall of the bobbin case through the bobbin thread take-out hole fits into the bobbin thread guide groove formed in the peripheral wall, and in this state, the bobbin thread is moved to the outer periphery of the peripheral wall. The lower thread is inserted into the lower thread guide groove and the lower thread fitting recess by guiding the lower thread to the lower thread fitting recess by inserting the lower thread into the lower thread fitting recess along the surface. The lower thread is returned to the free end side of the lower thread tension spring again by disposing the lower thread to the free end side of the lower thread tension spring, so that the lower thread extends from the fitting recess to the free end of the lower thread tension spring. Can be elastically pressed by the lower thread tension spring. The bobbin thread thus taken out from the bobbin thread take-out hole of the end wall of the bobbin case is easily interposed between the bobbin thread tension spring and the outer peripheral surface of the peripheral wall to stabilize the bobbin thread on the bobbin thread path. In this state, the lower thread can be pulled out with a desired tension. The bobbin case is provided with a latch and an operation piece for displacing the latch. The latch has a first through hole, and a first through hole and an outer surface facing the operation piece. A second lower thread guide groove extending between the lower thread guide grooves is formed. The lower thread pulled out from the lower thread take-out hole of the end wall fits into the second lower thread guide groove between the latch and the operation piece, and can be guided to the lower thread guide groove. ,
Undesirably large tension is prevented from being generated by the lower thread being sandwiched between the latch and the operation piece, and the lower thread can be supplied smoothly. Further, since the lower thread insertion hole is formed in the operation piece between the second through hole and the outer peripheral surface of the operation piece, the lower thread insertion hole is inserted through the lower thread take-out hole to be drawn out from the first and second through holes. Insert the lower thread into the lower thread insertion hole
Can be inserted simply by pulling it into the lower thread guide groove.
This eliminates the need to pull out the lower thread from the lower thread insertion hole and the first through hole in a state where the operation piece is angularly displaced in the direction away from the latch, and therefore, the operation piece remains substantially parallel to the latch. The lower thread can be inserted into the second lower thread guide groove by inserting the lower thread into the lower thread insertion hole and pulling the lower thread so as to be interposed between the latch and the operation piece. No effort is required to fit the lower thread guide groove 2 into the lower thread guide groove, and workability can be remarkably improved. Moreover, the lower thread insertion hole is formed so as to be inclined in a direction approaching the second lower thread guide groove of the latch as it goes from the outer surface of the operation piece toward the inner surface facing the latch.
The lower thread can be guided to the second lower thread guide groove of the latch without lifting the operation piece, and the work of mounting the lower thread in the second lower thread guide groove can be easily performed.

According to the second aspect of the present invention, since the free end of the lower thread tension spring is bent in a direction away from the outer peripheral surface of the peripheral wall, the free end is pulled out from the lower thread take-out hole of the end wall. In a state where the lower thread is partially fitted in the lower thread guide groove, the lower thread tension spring can be easily lowered from a gap formed between the free end of the lower thread tension spring and the outer peripheral surface of the peripheral wall. Can be inserted into
The mounting operation of the lower thread tension spring of the lower thread can be easily performed.

[0022]

[0023]

[Brief description of the drawings]

FIG. 1 is a perspective view showing a bobbin case 41 according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view showing a state in which a lower thread tension spring 48 is removed from a bobbin case main body 58.

FIG. 3 is a perspective view showing a latch 55;

FIG. 4 is a perspective view showing an operation piece 57.

FIG. 5 is an enlarged cross-sectional view taken along the line VV of FIG. 4;

FIG. 6 is an enlarged sectional view taken along the line VI-VI in FIG. 4;

FIG. 7 is an enlarged view showing the vicinity of a lower thread insertion hole 70;

FIG. 8 shows a typical prior art bobbin case 1 with a bobbin 2;
FIG.

9 is a perspective view showing a winding bobbin 31. FIG.

[Explanation of symbols]

 41 bobbin case 42 peripheral wall 43 end wall 44 bobbin thread 45 bobbin thread fitting recess 46 outer peripheral surface 47 bobbin thread tension spring 48 base end section 51 free end section 52 bobbin thread take-out hole 53 bobbin thread guide groove 54 first through hole 55 latch 56 second through-hole 57 operation piece 59 bobbin thread insertion part 60 bobbin thread removal prevention part 61 bobbin thread guide surface 68 second bobbin thread guide groove 70 bobbin thread insertion hole

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) D05B 57/26

Claims (2)

(57) [Claims] 1. A peripheral wall and an end wall for closing one end in the axial direction of the peripheral wall. A lower thread fitting concave portion into which the lower thread is fitted is formed in the peripheral wall, and a peripheral thread of the peripheral wall is formed on the peripheral wall. A lower thread tension spring is provided to resiliently close the lower thread fitting recess, a lower thread insertion hole through which the lower thread is inserted is formed in the end wall, and a peripheral edge of the end wall is formed in the peripheral wall. A first lower thread guide groove into which the lower thread is fitted from the lower thread fitting recess to the lower thread fitting recess is formed, and the lower thread take-out hole is formed in a central portion including the center axis of the end wall, and the end wall has A latch formed with a first through-hole communicating with the lower thread take-out hole formed in the center portion, and having one end in the longitudinal direction along one diameter line of the bobbin case with respect to the lower thread guide groove; The latch is provided so as to be displaceable in the direction of approaching / separating on the diameter line, and the latch communicates with the first through hole in a state of being stacked on the latch. An operation piece in which a through hole is formed is connected to the vicinity of one end in the longitudinal direction so as to be angularly displaceable, and an outer surface of the latch facing the operation piece extends between the first through hole and the first lower thread guide groove. A second lower thread guide groove extending is formed, and the operation piece has a lower thread insertion hole that communicates between the second through hole and the outer surface on one side in the width direction perpendicular to the longitudinal direction of the operation piece. The lower thread insertion hole is formed so as to be inclined in a direction approaching the second lower thread guide groove of the latch as it goes from the outer surface of the operation piece toward the inner surface facing the latch. And bobbin case. 2. The bobbin case according to claim 1, wherein the free end of the lower thread tension spring is formed to be bent in a direction away from the outer peripheral surface of the peripheral wall.