WO2015174568A1

WO2015174568A1 - Bobbin case of sewing machine

Info

Publication number: WO2015174568A1
Application number: PCT/KR2014/004452
Authority: WO
Inventors: 윤영수
Original assignee: 윤영수
Priority date: 2014-05-14
Filing date: 2014-05-19
Publication date: 2015-11-19
Also published as: KR20150130855A

Abstract

The present invention relates to a bobbin case mounted under a needle plate of a sewing machine. The bobbin case comprises: a housing assembly fixed on the lower part of the needle plate of the sewing machine and having a cutaway portion on the side thereof; a bobbin receiving unit, received inside the housing assembly to be relatively rotatable, having a bobbin receiving shaft and an upper thread clamp part; a driving force delivering assembly for delivering driving force to the bobbin receiving unit; a bobbin, inserted into the bobbin receiving shaft and received by the bobbin receiving unit; and a fixing means coupled to the bobbin receiving shaft.

Description

Bobbin device of sewing machine

The present invention relates to a drum collecting device mounted below the needle plate of the sewing machine.

The sewing machine includes a needle plate and a drum collecting device disposed below the needle plate. The bobbin device is a device for supplying the lower thread while rotating in one direction by driving the drive shaft of the sewing machine.

As disclosed in the Republic of Korea Patent No. 1010835, the conventional conventional bobbin device is assembled with the outer bobbin, which is integrally coupled to the drive shaft, the inner bobbin rotatably provided relative to the outer bobbin, and the bobbin case detachably mounted to the inner bobbin. Structure.

The bobbin thread is wound around the bobbin and stored inside the bobbin case. The outer surface of the outer bobbin is provided with an inclined surface for guiding the lower thread, and a hook tip for extending the upper thread formed continuously therefrom.

The outer bobbin is fixed to the drive shaft of the sewing machine and rotates from the lower side of the needle plate by the drive of the drive shaft, and the inner drum is suppressed by the stop member provided on the needle plate, so that the outer bobbin and the inner bobbin rotate relatively. By the relative rotation of the outer bobbin and the inner bobbin, the bobbin thread is guided through the inclined surface formed on the outer surface of the outer bobbin, and the upper thread loop is opened by the hook tip of the outer bobbin, whereby the bobbin thread and the upper thread are entangled with each other to form a stitch. To form.

The conventional drum case has a weak durability in the way that the outer drum is rotated with a relatively large weight eccentricity relative to the drive shaft of the sewing machine.

In addition, the conventional bobbin device has a structure in which the outer bobbin is integrally coupled to the drive shaft of the sewing machine, so that the operation of separating the entire bobbin device from the drive shaft should be preceded when replacing the bobbin device. Accordingly, the work of replacing the bobbin device is cumbersome and time consuming. Moreover, inefficiency of the sewing work is further increased because additional work is required to prevent eccentricity in the process of mounting the outer drum to the drive shaft.

In addition, since the conventional bobbin device has a structure in which the inclined surface for guiding the lower thread is formed in the shape of spirally diverging from the center of the outer bobbin outer surface, the bobbin case and bobbin accommodated inside the bobbin to secure the inclined surface area. The diameter can only be reduced relatively. Accordingly, in a situation where the outer diameter of the outer bobbin is limited in accordance with the sewing machine standard, the amount of bobbin windable around the bobbin is reduced and the relative replacement cycle of the bobbin is short, which is undesirable.

In addition, in the case of a conventional bobbin device, since the elements for fixing the bobbin are integrally formed in the bobbin case, it is troublesome to separate the bobbin case from the inner bobbin in order to take out the bobbin for replacing the lower thread.

On the other hand, for the continuity of sewing operations, it is preferable that the breakage of the lower thread is suppressed as much as possible. There is a possibility that the lower thread is broken by frictional heat due to excessive tension or high-speed rotation applied during the sewing operation, but the conventional bobbin device is not provided with satisfactory means for mitigating it.

The present invention has been made to solve the above problems, to provide a sewing apparatus of the sewing machine that is compatible with the conventional sewing machine, while improving durability and easy maintenance.

It is another object of the present invention to provide a sewing apparatus for a sewing machine, in which a bobbin winding amount is increased in the outline size of a standardized packaging apparatus.

Still another object of the present invention is to provide a bobbin device of a sewing machine, in which a bobbin thread phenomenon is suppressed in a working process.

The gist of the present invention based on the recognition of the above-mentioned problem is as follows.

(1) a housing assembly fixed to the lower part of the needle plate of the sewing machine and having a cutout at a side thereof; A bobbin accommodating unit which is accommodated rotatably inside the housing assembly and has a bobbin receiving shaft and an upper thread engaging portion; A driving force transmitting assembly for transmitting driving force to the bobbin receiving unit; A bobbin inserted into the bobbin receiving shaft and accommodated in the bobbin receiving unit; And a fixing means coupled to the bobbin receiving shaft.

(2) The housing assembly, the housing main body provided with the cutout; A front guard coupled to the front of the housing body to receive the bearing; And a rear guard coupled to the rear of the housing body and fixed to the sewing machine, wherein the rear guard is formed with an opening for exposing the upper thread engaging portion in the process of rotating the bobbin receiving unit, wherein (1) The bobbin device of the sewing machine according to).

(3) The bobbin device of the sewing machine according to (1), wherein a spiral portion for guiding the lower thread is formed on the outer surface of the bobbin accommodation unit.

(4) The drum assembly of the sewing machine according to (1), wherein the housing assembly and the bobbin accommodation unit are provided with a pair of guide plates for guiding the lower thread.

(5) The drum assembly of the sewing machine according to (1), wherein holes at the sides of the housing assembly and the bobbin accommodation unit are machined to check the remaining amount of bobbin.

(6) The bobbin device of the sewing machine according to (5), wherein the bobbin is provided with a thread winding amount check mark recognized through the hole.

(7) the drive force transmission assembly, the gear is fixed to the drive shaft of the sewing machine; And a bearing which is provided between the housing assembly and the bobbin receiving unit and engages the gear and the bobbin receiving unit.

(8) The engagement between the bearing and the bobbin accommodation unit is such that the engaging projection provided at a distance from the center of the bearing is accommodated in a receiver formed on the bottom surface of the bobbin accommodation unit. The bobbin device of the sewing machine according to).

(9) The drum assembly of the sewing frame according to (8), wherein an end face of the locking projection is a curved surface.

(10) The drum assembly according to the sewing frame (7), wherein the bearing is formed with a plurality of heat dissipation holes.

In the bobbin device according to the present invention, the bobbin receiving unit is in close contact with the inside of the housing assembly and stably rotates, thereby reducing noise and improving durability problems due to eccentric rotation.

In addition, the drum collecting device is provided with a separate drive transmission means including a gear and a bearing to facilitate maintenance of the drum collecting device.

In addition, the bobbin device is provided with a separate fixing means to be mounted on the bobbin receiving unit, it is easy to replace the lower thread maintenance.

In addition, the bobbin collecting device may naturally be restrained and drawn out between the inner surface of the housing body and the outer surface of the bobbin receiving unit, thereby increasing the bobbin winding amount by securing the maximum inner diameter of the bobbin receiving unit.

In addition, the bobbin device can minimize the phenomenon that the lower thread is turned off by controlling the tension and heat applied to the lower thread in the sewing process.

In addition, the bobbin device can check in advance the amount of winding of the lower thread in the sewing process.

1 and 2 are perspective views of the assembly state of the bobbin device according to an embodiment of the present invention.

3 is an exploded perspective view of a bobbin device according to an embodiment of the present invention.

4 is a rear perspective view of the housing main body according to the embodiment of the present invention;

5 is a rear perspective view of the bobbin receiving unit according to the embodiment of the present invention;

6 is a rear perspective view of a bearing according to an embodiment of the present invention.

7 is a perspective view of a bobbin according to an embodiment of the present invention.

8 is an exploded perspective view of the fixing means according to the embodiment of the present invention.

9 is an assembled state diagram of the fixing means according to the embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same or equivalent reference numerals are given the same or similar reference numerals.

In addition, throughout the specification, when a portion is to include a certain component, which means that it may further include other components, except for the other components, unless specifically stated otherwise.

In addition, when any component is provided as 'optionally' provided, provided or included, it is not an essential component for the solution of the present invention, but it can be arbitrarily adopted in terms of such a solution. it means.

Hereinafter, the structure and the operation of the drum collecting device will be described in a direction in which the bobbin device of the sewing machine is coupled to the drive shaft of the sewing machine in the front and the opposite direction in the rear.

1 and 2 are perspective views of an assembled state of the bobbin device 10 according to the embodiment of the present invention, Figure 3 shows an exploded perspective view of the bobbin device 10, respectively. 7 is a perspective view of a bobbin according to an embodiment of the present invention, Figure 8 is an exploded perspective view of the fixing means according to an embodiment of the present invention, respectively.

1 to 3, the drum collecting device 10 includes a housing assembly 100 (110, 120, 130), a bobbin receiving unit 200, and a driving force transmitting assembly 300. The bobbin 400 shown in FIG. 7 is fixed by the fixing means 500 shown in FIG. 8 in a state of being accommodated in the bobbin accommodation unit 200. In FIGS. 1 and 2, the bobbin 400 of FIG. 7 and the fixing means 500 of FIG. 8 are omitted for convenience. The bobbin 400 of FIG. 7 and the fixing means 500 of FIG. 8 are illustrated in FIGS. 1 to 3. ) Are omitted for convenience.

First, as shown in Figures 1 to 3, the housing assembly 100 is fixed to the needle plate (not shown) of the sewing machine, the housing is provided with a cutout 114 is drawn out the lower thread (not shown) The main body 110, the front guard 120 coupled to the front of the housing main body 110, and the rear guard 130 coupled to the rear of the housing main body 110 are assembled. In an embodiment, each of the front guard 120 and the rear guard 130 may be assembled to the housing body 110 with bolts (not shown).

Optionally, as shown in FIG. 4, a hole 116 for checking the actual remaining amount of the bobbin 400 may be processed at the side of the housing main body 110, and correspondingly accommodated in the housing main body 110. The hole 226 is also machined in the side surface of the bobbin accommodation unit 200 (see FIG. 5).

In addition, as shown in Figure 3, the side of the housing main body 110 is provided with a guide plate 118 for guiding the lower thread, which is a guide plate provided in the bobbin receiving unit 200 as described later ( 228) to work in pairs.

Between the front guard 120 and the housing main body 110, a bearing 320 constituting the driving force transmission assembly 300 is accommodated. As shown in FIG. 3, the front guard 120 and the front inner surface of the housing main body 110 have a pair of

flanges

122 and 112A for supporting the edge of the bearing 320 to be slid and rotated. It is provided.

As shown in FIG. 3, the bobbin accommodating unit 200 is rotatably received in the rear of the housing main body 110 with the front flange 112 as the boundary. On the rear inner side of the rear guard 130 and the housing body 110, a pair of flanges 132 for supporting the flange 222 provided on the outer side of the rear end of the bobbin receiving unit 200 to be slid and rotated, 112B).

In this case, the interval between the

flanges

112A and 112B provided inside the housing main body and the interval between the pair of

flanges

132 and 112B are such that the bobbin accommodation unit 200 is applied to a predetermined situation, for example, a bobbin thread. It is designed to move finely forward and backward according to strength and weakness.

As shown in FIG. 3, the rear guard 130 has an opening portion 134 for exposing the upper thread catching portion 224 in the process of rotating the bobbin receiving unit 200 by the driving force transmitting assembly 300. It is provided. In addition, the rear guard 130 is formed with a fixed end 136 for fixing the drum assembly 10 extending in the radial direction.

Next, referring to FIGS. 3 and 5, the bobbin receiving unit 200 has a cup shape in which the front side is sealed by the bottom surface 210 and the side wall 220 extends in the rear side.

The bottom surface 210 is provided with a hole-shaped receiver 212 that engages with the engaging projection 322 of the bearing 320 shown in Figure 6, the bobbin 400 on the inner surface of the bottom surface 210 The inserted bobbin receiving shaft 214 extends backward. On the side of the bobbin receiving shaft 214, the slide groove 214A into which the clip 540 is inserted is formed symmetrically.

At the rear end of the side wall 220, a hook-shaped upper thread engaging portion 224 extends in the rotational direction. The upper thread catching part 224 serves to hang the upper thread loop supplied from the sewing needle (not shown) in the sewing process. In addition, a spiral portion 229 for guiding the lower thread is formed in a part of the middle region of the side wall 220. In this case, the spiral portion 229 covers a portion of the circumferential surface of the side wall 220.

As described above, the flange 222 accommodated and supported between the rear guard 130 and the pair of

flanges

132 and 112B provided on the rear inner surface of the housing body 110 on the outer side of the rear end of the side wall 220. Is provided. In addition, a hole 226 for processing the remaining amount of the bobbin 400 is processed in a predetermined region of the side wall 220, and the hole 226 is formed in the hole 116 provided on the side of the housing main body 110. Corresponding.

In addition, as shown in Figure 3, the side wall 220 is provided with a guide plate 228 for guiding the lower thread, which cooperates in pairs with the guide plate 118 of the housing body 110 described above. .

Next, as shown in FIG. 3, the driving force transmitting assembly 300 includes a gear 310 fixed to a driving shaft (not shown) of the sewing machine, a front guard 120 of the housing assembly, and a bobbin receiving unit ( It includes a bearing 320 installed between the 200.

In an embodiment, the gear 310 has a flat cross shape and is provided with a hole 312 into which the drive shaft is inserted, and a bolt fastening hole 314 for fixing to the side of the drive shaft.

The gear receiving portion 324 meshing with the gear 310 is protruded in the axial direction on the front surface of the bearing 320 in the form of a plurality of protrusions around the center. As described above, the rear surface of the bearing 320 is provided with a locking projection 322 for engaging the receiver 210 of the bottom surface 210 (see Fig. 6).

As shown in Figure 6, the end face shape of the locking projection 322 is preferably configured in a curved shape to adjust the tension applied to the lower thread. When the tension applied to the lower thread in the sewing process exceeds a predetermined threshold, the bobbin receiving unit 200 is moved to the rear by the tension of the lower thread, and accordingly the locking projections 322 and the receiver 212 of the curved shape The engagement state is weakened or in some cases released momentarily. Accordingly, the engaging force between the locking projections 322 and the receiver 212 becomes smaller than the tension applied to the lower thread so that the rotation of the bobbin receiving unit 200 is suppressed and the lower thread is disconnected due to excessive tension. Can be effectively prevented.

A plurality of heat dissipation holes 326 are provided around the center of the bearing 320. Friction heat generated from the bobbin receiving unit 200 and the bobbin 400 at high speed can be effectively cooled by the air entering and exiting through the heat dissipation hole 326, and thus may be broken due to heat of the lower thread. Can be reduced.

On the other hand, the gear 310 is not separated from the drive shaft in the process of replacing the drum unit 10, the drum unit 10 in the state in which the bearing 320 is assembled through the above-mentioned gear receiving unit 324 It can be replaced by simply inserting into the gear 310, it is possible to easily replace the entire collection device 10.

Next, referring to FIG. 7, the bobbin 400 has a structure in which a circular plate 420 is integrally formed from both ends of the tubular winding 410. The bobbin receiving shaft 214 of the bobbin receiving unit 200 is inserted into the tubular winding part 410.

The mark 422 recognizable through the

holes

116 and 226 provided in the housing main body 110 and the bobbin accommodation unit 200 is grooved in the center direction inside the at least one circular plate 420.

In this case, as the bobbin receiving unit 200 rotates, the hole 226 of the bobbin receiving unit 200 is periodically aligned with the hole 116 of the housing main body 110 in a stationary state, and is installed externally in the aligned state. By instantly recognizing the state of the mark 422 using an image device (not shown), it is possible to confirm in advance the replacement time of the lower thread. For example, as the amount of the lower thread remaining in the bobbin 400 decreases, the exposed area of the mark 422 increases, and when the exposed area reaches a predetermined value, the replacement timing is determined based on a signal transmitted from the imaging apparatus. Able to know.

On the other hand, in the present invention, the cup-shaped bobbin receiving unit 200 as the rotating element is a structure that is mounted in close contact with the inside of the cylindrical housing main body 110 as a fixed element and the lower thread is the inner surface of the housing main body 110 and the bobbin By allowing it to be naturally constrained and drawn between the outer surfaces of the receiving unit 200, unlike the prior art, a separate face element having a spiral shape emanating from the center in order to guide the lower thread to the outer surface of the outer bobbin is unnecessary. Accordingly, the inner diameter of the bobbin accommodation unit 200 and the diameter of the circular plate 420 can be secured to the maximum, and the bobbin winding amount in the bobbin 400 even in a situation where the outer diameter of the entire bobbin device is limited according to the sewing machine standard. Is advantageously increased.

Next, referring to FIG. 8, the fixing means 500 according to the embodiment of the present invention may include a cover 510, a locking slider 520, a tab 530, and a clip 540. 9 illustrates a state in which the cover 510, the locking slider 520, and the tab 530 are assembled.

The cover 510 is composed of a disc shaped cover body 512 and a fixed shaft 513. On the upper surface of the cover body 512, a rail 512A into which the locking slider 520 is inserted and a locking hole 512B into which the bent portion 532 of the tab 530 is inserted are fixed. The fixed shaft 513 is configured in a tubular shape, the inner diameter of the clip 540 is designed to be fitted to fit in the elastically contracted state, the outer diameter of the tubular winding portion 410 of the bobbin can be inserted It is designed to be. The interior of the fixed shaft 513 is designed to limit the insertion of the clip 540 over a predetermined distance (not shown). One of the clips 540 is open and is inserted into the slide groove 214A provided in the bobbin accommodation shaft 214 of the bobbin accommodation unit 200 through the open portion. The center of the locking slider 520 is provided with a central hole 524 substantially coincident with the inner diameter of the fixed shaft 513, and at the end side, a locking hole 522B having the same shape as the locking hole 512B of the cover body 512. Is provided. The center of the tab 530 is provided with a central hole 534 substantially coincident with the inner diameter of the fixed shaft 513, and at the end side of the locking slider 520 and the locking

holes

522B and 512B of the cover body 52. There is provided a bend 532 to be inserted. The tab 540 is hinged to the cover 510 while the bent portion 532 passes through the locking

holes

522B and 512B.

The manner in which the fixing means 500 is fixed to the bobbin receiving shaft 214 is that the fixing shaft 513 receives the bobbin while the clip 540 is engaged by the slide groove 214A of the bobbin receiving shaft 214. The inner wall surface of the fixed shaft 513 is inserted into the shaft 214 to pressurize the outer surface of the clip 540. In this case, the elastic deformation force of the clip 540 provides a friction force between the slide groove 214A and the inner wall surface of the fixed shaft 513. Release of the engagement state between the fixing means 500 and the bobbin receiving shaft 214 is performed by pulling the tab 540 hinged to the cover body 512.

Unlike the related art, the fixing means 500 is separated from the bobbin receiving unit 200, thereby releasing the locking state of the fixing means 500 while maintaining the mounting state of the bobbin receiving unit 200. Since only 400) can be replaced, changing the bobbin thread is simple and easy.

It describes the process of assembling and detaching the bobbin device 10 of the sewing machine according to the present invention. First, the gear 310 constituting the driving force transmission means is fixedly coupled to a drive shaft (not shown) located under the needle plate of the sewing machine. Next, as shown in FIG. 3, after mounting the bearing 320 and the housing main body 110 constituting the driving force transmission means to the rear of the front guard 120 in sequence, the front guard 120 and the housing main body. Join 110. Next, the bobbin receiving unit 200 is mounted on the housing main body 110, and the rear guard 130 is coupled to the rear end of the housing main body 110. Subsequently, the bobbin 400 is fixed using the fixing means 500 in a state where the bobbin 400 is inserted into the bobbin accommodation shaft 214 of the bobbin accommodation unit 200. Finally, the installation work is completed by fixing the fixed end 136 of the rear guard 130 to the sewing machine at a predetermined position in a state where the bearing 320 of the drum collecting device 10 is engaged with the gear 310 pre-installed on the drive shaft. . The process of separating the bobbin device 10 for the purpose of replacement or maintenance is performed by releasing the engagement of the fixed end 136 and the sewing machine and relieving the engagement of the gear 310 and the bearing 320. .

As described above, the gear 310 is not separated from the driving shaft during the detachment process of the drum collecting device 10, and the drum collecting device 10 in which the bearing 320 is assembled through the gear receiving unit 324. It can be carried out by simply inserting or detaching the gear 310, it is possible to easily detach the entire collection device 10.

In addition, since each component element of the drum collecting device 10 according to the present invention is provided and assembled separately, the replacement cost may be reduced when the component unit is replaced.

The operation of the book collecting device 10 according to the present invention will be described. The gear 310 is rotated by the drive of the drive shaft provided in the sewing machine. It rotates by the drive of the motor (not shown) provided to the sewing machine of a drive shaft. The bearing 320 is rotated by the driving of the gear 310 in an engaged state via the gear 310 and the gear receiving portion 324. In this case, the edge of the bearing 320 is supported to be slidably rotated between the flange 122 of the front guard 120 and the front flange 112A of the housing body 110. The bobbin receiving unit 200 rotates by driving the bearing 320 in a state where the bobbin receiving unit 200 is engaged with the locking protrusion 322 provided on the rear surface of the bearing 320 and the receiver 212. In this case, the bobbin receiving unit 200 has its front end supported by the front flange 112A of the housing main body 110 and its rear end flange 222 is the rear flange 112B and the rear of the housing main body 11. It is supported to be slid and rotated between the flange 132 of the guard 130. The housing assembly 100 is fixed to the sewing machine and does not rotate. As the bobbin receiving unit 200 rotates inside the housing assembly 100, the lower thread is guided to the spiral portion 229 and the pair of

guide plates

228 and 118 and supplied to the outside.

In the bobbin device 10 according to the present invention, the bobbin accommodation unit 200 is accommodated inside the housing assembly 100 and rotated, so that noise can be reliably reduced, and the eccentric rotation of the bobbin accommodation unit 200 is minimized. By being suppressed, durability can be improved.

The foregoing descriptions relate to specific embodiments of the present invention but are not to be construed as limiting the scope of the present invention as matters disclosed for the purpose of explanation are always disclosed.

For example, in the embodiment, the housing assembly has a structure in which the cylindrical housing body 110, the front guard 120, and the rear guard 130 are assembled as separate components, but may be manufactured integrally, such as casting. In the case of the detachable structure, there is an advantage in that partial replacement is possible in case of partial breakage of the component elements of the housing assembly, and in the case of the integral structure, manufacturing cost can be reduced.

In addition, in the embodiment, the structure in which the bearing 320 and the bobbin receiving unit 200 are engaged is illustrated as engaging the engaging projection 322 and the receiver 212 formed to be spaced apart from the center, but also engaged in the form of gears In this case, it is possible to release the engagement between the bearing 32 and the bobbin receiving unit 200 according to the tension applied to the bobbin thread by adjusting the dimensions of the gear.

In addition, in the embodiment, the receiver 212 engaged with the locking protrusion 322 is a hole shape, but may be configured in a groove shape.

In addition, although the planar shape of the gear 310 in the embodiment illustrated a cross shape, other planar shapes are possible.

In addition, in the embodiment, but the locking projection 322 provided on the rear surface of the bearing 320 is provided as an integral, it may be a structure provided and assembled as a separate component.

In addition, the mark 422 formed on the circular plate 420 of the bobbin 400 is a predetermined mark recognizable by the image device, and is not limited to the groove shape as in the embodiment.

In addition, the pair of

guide plates

118 and 228 provided in the housing main body 110 and the bobbin accommodation unit 200 may be provided as separate components as in the embodiment, or the housing main body 110 or the bobbin accommodation may be provided. It may be provided integrally to the unit 220.

In addition, in the embodiment illustrated the case in which the fixed end 136 of the rear guard 130 is mounted directly fixed to the sewing machine, for example, when the sewing machine specifications, such as industrial sewing machine is different as shown in Figure 3 fixed It is also possible that the end 136 is fixed to the sewing machine via a separate fixing support 600.

In addition, in the embodiment, the fixing means 500 and the bobbin receiving shaft 214 are fixed in the winding part 410 of the bobbin 400. Optionally, the bobbin receiving shaft 214 is designed to completely penetrate the windings 410 of the bobbin and pass through the locking slider 520 of the fixing means 500 and the

central holes

524, 534 of the tab 530. It is also possible to end the bobbin receiving shaft 214 with the inner circumference of the

central holes

524 and 534. In this case, the unlocking may be performed by hingedly moving the tab 530 so that the locking slider 520 is guided to the rail 512A of the cover body 510 and slightly moved.

Accordingly, all such modifications and variations can be understood as fall within the scope of the invention as set forth in the claims or their equivalents.

Claims

A housing assembly fixed to the lower part of the needle plate of the sewing machine and having a cutout at a side thereof; A bobbin accommodating unit which is accommodated rotatably inside the housing assembly and has a bobbin receiving shaft and an upper thread engaging portion; A driving force transmitting assembly for transmitting driving force to the bobbin receiving unit; A bobbin inserted into the bobbin receiving shaft and accommodated in the bobbin receiving unit; And a fixing means coupled to the bobbin receiving shaft.
The method of claim 1, wherein the housing assembly,

A housing body having the cutout; A front guard coupled to the front of the housing body to receive the bearing; And a rear guard coupled to the rear of the housing body and fixed to the sewing machine,

The rear guard, the bobbin device of the sewing machine, characterized in that the opening is formed for exposing the upper thread engaging portion in the process of rotating the bobbin receiving unit.
The bobbin device of the sewing machine according to claim 1, wherein a spiral portion for guiding a lower thread is formed on an outer surface of the bobbin accommodation unit.
The bobbin device of the sewing machine according to claim 1, wherein the housing assembly and the bobbin accommodation unit are provided with a pair of guide plates for guiding the lower thread.
The bobbin device of the sewing machine according to claim 1, wherein a hole for checking the remaining amount of bobbin is machined from the side of the housing assembly and the bobbin accommodation unit.
The bobbin device of the sewing machine according to claim 5, wherein the bobbin is provided with a thread winding check mark recognized through the hole.
The method of claim 1, wherein the drive force transmission assembly,

A gear fixed to the drive shaft of the sewing machine; And a bearing installed between the housing assembly and the bobbin receiving unit and engaged with the gear and the bobbin receiving unit.
The method of claim 7, wherein the engagement between the bearing and the bobbin receiving unit,

The hooking device of the sewing machine, characterized in that the locking projection spaced apart from the center of the bearing is accommodated in the receiver formed on the bottom surface of the bobbin receiving unit.
The bobbin device of the sewing machine according to claim 8, wherein the end face of the locking projection is a curved surface.
8. The sewing apparatus of the sewing machine according to claim 7, wherein the bearing is provided with a plurality of heat dissipation holes.