TWI807247B - Sewing Machine Structure - Google Patents

Abstract

A sewing machine structure comprising a needle bar reciprocating on a vertical axis, a connecting rod for pushing the needle bar and a driving shaft for driving the connecting rod. The connecting rod has a first end connected to the driving shaft and a second end connected to the needle bar. The first end is moved on a circular trajectory by the driving shaft. The height of the first end of the connecting rod relative to a needle plate is always lower than the height of the second end relative to the needle plate. When the first end of the connecting rod is displaced counterclockwise from the three o’clock position of the circular trajectory to the twelve o’clock position, the needle bar travels an upstroke displacement distance. The machine structure is suitable for various fabrics.

Description

Sewing Machine Structure

The invention relates to a sewing machine structure, in particular to a sewing machine structure which changes the displacement distance of up and down strokes to adapt to multiple types of cloth.

Nowadays, due to the mature technology of the textile industry and the development of material technology, a variety of fabrics with different material properties from traditional fabrics have been developed. Moreover, with the improvement of economic standards, the appearance and wear are gradually paid attention to, causing people to advocate fashion and fashion. Therefore, to match the diverse and complex designs of fashion designers, sewing methods must also be improved.

Existing sewing machines use mechanisms such as adjusting the differential ratio of the feed teeth or yarn tension to cope with a variety of fabrics of different thicknesses. Regarding the mechanism for adjusting the differential ratio of the feed teeth, as disclosed in patents such as TW I271457 and TW M509814, conventional sewing machines can adapt to the increase in fabric types by adjusting the movement strokes of the front and rear feed teeth so that the amount of cloth brought in by the front feed teeth is the same or more or less than that of the rear feed teeth (such as the differential ratio).

However, the current sewing machine is carried out by changing the surrounding matching components, that is to say, the conventional sewing machine cannot directly change the position of the drive shaft and the stroke distance of the needle bar, so that the conventional sewing machine must take the drive shaft and the stroke of the needle bar into consideration when adjusting the differential ratio of the feed gear or the yarn tension, which makes the design and improvement process of the conventional sewing machine cumbersome.

The main purpose of the present invention is to solve the problem that the conventional sewing machine structure can only change the surrounding matching elements to adapt to multiple types of fabrics.

In order to achieve the above object, the present invention provides a sewing machine structure, which includes a needle bar that is driven to reciprocate on a vertical axis, a connecting rod that pushes the needle bar, and a driving shaft that drives the connecting rod. The connecting rod has a first end that is connected to the driving shaft and a second end that is connected to the needle bar. Further, the height of the first end of the connecting rod relative to a needle plate is always lower than the height of the second end of the connecting rod relative to the needle plate. When the first end of the connecting rod is displaced counterclockwise from the three o’clock position of the circular trajectory to the twelve o’clock position, the needle bar travels an upstroke displacement distance. .

In one embodiment, the driving shaft has a cam assembled with the connecting rod, and the cam is formed with an eccentric portion assembled with the first end.

In one embodiment, the sewing machine structure includes an upper housing and a lower housing connected with the upper housing and provided with the needle plate. The upper housing is formed with a chamber, and the drive shaft, the connecting rod and the needle bar are assembled in the chamber. The housing has a track that is arranged in the chamber and is higher than the drive shaft to restrict the second end to move only along the vertical axis.

In one embodiment, the chamber is divided into a top and a bottom by a center line, the driving shaft is located at the bottom, and the track is located at the top.

In one embodiment, the sewing machine structure includes a lower hook located in the lower housing, and a hook drive shaft arranged in the lower housing, the lower hook has a mounting portion assembled with the hook driving shaft, a straight extension extending from the mounting portion, an oblique extension extending from the end of the straight extension not connected to the installation portion, and a hooking portion extending from the oblique extension toward the installation portion.

According to the content of the foregoing invention, compared with the conventional technology, the present invention has the following features: the upstroke displacement distance of the needle bar at the first end of the connecting rod from the three o’clock position of the circular trajectory counterclockwise to the twelve o’clock position is longer than the downstroke displacement distance of the needle bar at the first end of the connecting rod from the six o’clock position of the circular trajectory counterclockwise to the three o’clock position. For example, the upstroke displacement distance can be designed to be at least 10 mm , so that the types of fabrics that the structure of the sewing machine can adapt to are more diverse. Furthermore, the present invention makes the length of the hooking portion of the lower hook hook shorter than conventional ones through the aforementioned structure, so that the space in the lower casing can be released, thereby making the tangent of the hooking portion more stable.

The detailed description and technical content of the present invention are described as follows in conjunction with the drawings:

1 to 5, the present invention provides a sewing machine structure 10, the sewing machine structure 10 includes a needle bar 11, a connecting rod 12 and a drive shaft 13, wherein the needle bar 11 is connected to the connecting rod 12, the needle bar 11 is driven by the connecting rod 12 and reciprocated on a vertical shaft 111, the driving shaft 13 is connected to the end of the connecting rod 12 away from the needle bar 11, and the driving shaft 13 drives the sewing machine structure 10 when it is in operation. Connecting rod 12 activities. The connecting rod 12 is connected to the driving shaft 13 and the needle bar 11. The connecting rod 12 has a first end 121 connected to the driving shaft 13 and a second end 122 connected to the needle bar 11. When the connecting rod 12 is driven by the driving shaft 13, the first end 121 of the connecting rod 12 moves on a circular track 123. When the first end 121 moves on the circular track 123 , the height of the first end 121 relative to a needle board 14 is always lower than the height of the second end 122 relative to the needle board 14 . 1, when the first end 121 of the connecting rod 12 is displaced counterclockwise from the six o'clock position (such as 124) of the circular track 123 to the twelve o'clock position (such as 125) of the circular track 123, the needle bar 11 is narrowed. During the narrowing process of the needle bar 11, when the first end 121 of the connecting rod 12 is displaced counterclockwise from the three o’clock position (as marked 126) of the circular track 123 to the twelve o’clock position (as marked 125) of the circular track 123, the needle bar 11 travels an upstroke displacement distance 112. When the first end 121 of the connecting rod 12 is counterclockwise from the six o’clock position (as marked 124) of the circular track 123 When moving to the three o'clock position of the circular track 123 (as indicated by reference numeral 126 ), the needle bar 11 travels a down stroke displacement distance 113 , and the up stroke displacement distance 112 is longer than the down stroke displacement distance 113 .

The present invention changes the circular trajectory 123 when the first end 121 of the connecting rod 12 is driven by the drive shaft 13 , thereby achieving the purpose of changing the upstroke displacement distance 112 and the downstroke displacement distance 113 of the needle bar 11 . For example, through the present invention, the upstroke displacement distance 112 can be designed to be at least 10 mm, so that the sewing machine structure 10 can increase the types of fabrics it can adapt to. More specifically, the present invention does not adopt the conventional mechanism of changing the differential ratio of the feeding gear or the yarn tension, but makes the upstroke displacement distance 112 of the needle bar 11 longer than the downstroke displacement distance 113, so that the sewing machine structure 10 is no longer limited by the old sewing technology and can respond to more diverse types of fabrics.

Referring again to FIGS. 1 to 5 , from the perspective of the current drawing in FIG. 1 , when the first end 121 of the connecting rod 12 moves counterclockwise from the twelve o'clock position (such as 125 ) of the circular locus 123 to the six o'clock position (such as 124 ) of the circular locus 123 , the needle bar 11 will exit the needle. When the needle bar 11 is out of the needle, when the first end 121 of the connecting rod 12 is displaced counterclockwise from the twelve o’clock position (as marked 125 ) of the circular track 123 to the nine o’clock position (as marked 127 ) of the circular track 123 , the needle bar 11 travels the upward stroke displacement distance 112 , when the first end 121 of the connecting rod 12 is counterclockwise from the nine o’clock position (as marked 127 ) of the circular track 123 When the needle moves to the six o'clock position (eg, 124 ) of the circular track 123 , the needle bar 11 travels the distance 113 in the down stroke. In other words, regardless of whether the needle bar 11 is in the needle-out or needle-retracting process, each upstroke displacement distance 112 of the needle bar 11 when the first end 121 of the connecting rod 12 moves on the circular trajectory 123 from the three o'clock position to the nine o'clock position is greater than each downstroke displacement distance 113 of the needle bar 11 when the first end 121 of the connecting rod 12 moves on the circular trajectory 123 from the nine o'clock position to the three o'clock position, so that the The sewing machine structure 10 can sew more diverse cloth types.

On the other hand, the driving shaft 13 has a cam 131 assembled with the connecting rod 12. The cam 131 is formed with an eccentric portion 132 for assembling with the first end 121 of the connecting rod 12. The eccentric portion 132 drives the connecting rod 12 to move by pushing the first end 121.

On the other hand, referring to Fig. 1, the sewing machine structure 10 has an upper housing 15 and a lower housing 16, wherein the upper housing 15 is formed with a chamber 151 for the drive shaft 13, the connecting rod 12 and the needle bar 11 to be arranged therein, and the drive shaft 13, the connecting rod 12 and the needle bar 11 are assembled in the chamber 151. Also, the upper housing 15 has a rail 152 arranged in the chamber 151, the rail 152 is connected to the second end 122 of the connecting rod 12 and is higher than the drive shaft 13, the rail 152 restricts the second end 122 of the connecting rod 12 to move only along the vertical axis 111, and simultaneously assists in stabilizing the movement of the needle bar 11. In another embodiment, the chamber 151 is divided into a top 154 and a bottom 155 by a centerline 153 , the driving shaft 13 is located at the bottom 155 , and the track 152 is located at the top 154 .

1, FIG. 5 to FIG. 7, in one embodiment, the lower housing 16 is connected to the upper housing 15 and provided for the needle plate 14. The sewing machine structure 10 includes a lower crochet needle 17 and a lower crochet needle driving shaft 18. The lower crochet needle 17 is moved back relative to the needle plate 14 . The lower crochet needle 17 includes a mounting portion 171, a straight extension portion 172, an oblique extension portion 173 and a hook yarn portion 174. The installation portion 171 is connected to the lower hook hook drive shaft 18 and driven by the lower hook hook drive shaft 18. The straight extension portion 172 extends from the installation portion 171. The obliquely extending portion 173 extends toward the installation portion 171 . In the present invention, by changing the upstroke displacement distance 112 and the downstroke displacement distance 113 of the needle bar 11, the sewing machine structure 10 can be implemented with the lower crochet needle 17 of the present invention instead of using the conventional lower crochet needle. Further, through the reduced size of the hooking portion 174 of the lower hook 17 , the sewing machine structure 10 can release the space in the lower housing 16 , so that the lower hook 17 can cut the thread more stably.

To sum up, the above is only a preferred embodiment of the present invention, and should not limit the scope of the present invention, that is, all equivalent changes and modifications made according to the scope of the patent application of the present invention should still belong to the scope of the patent of the present invention.

10: Sewing machine structure 11: Needle bar 111: vertical axis 112: Upstroke displacement distance 113: Downstroke displacement distance 12: Connecting rod 121: first end 122: second end 123:Circular track 124: Six o'clock position 125: twelve o'clock position 126: three o'clock position 127: Nine o'clock position 13: drive shaft 131: cam 132: Eccentric part 14: Needle plate 15: Upper shell 151: chamber 152: track 153: center line 154: top 155: bottom 16: Lower shell 17: Lower crochet 171: Installation department 172: straight extension 173: Diagonal extension 174: hook yarn department 18: Lower crochet driving shaft

Fig. 1 is a schematic diagram (1) of the needle bar action of the sewing machine structure of the present invention. Fig. 2 is a schematic diagram (2) of the needle bar action of the sewing machine structure of the present invention. Fig. 3 is a schematic diagram (3) of the action of the needle bar of the sewing machine structure of the present invention. Fig. 4 is a schematic view (four) of the needle bar action of the sewing machine structure of the present invention. Fig. 5 is a schematic diagram of some components of the structure of the sewing machine of the present invention. Fig. 6 is a schematic diagram (1) of the lower crochet needle of the sewing machine structure of the present invention. Fig. 7 is a schematic diagram (2) of the lower crochet needle of the sewing machine structure of the present invention.

10: Sewing machine structure

11: Needle bar

112: Upstroke displacement distance

12: Connecting rod

121: first end

122: second end

125: twelve o'clock position

13: drive shaft

131: cam

14: Needle plate

15: Upper shell

151: chamber

152: track

153: center line

154: top

155: bottom

16: Lower shell

Claims (6)

A sewing machine structure comprising a needle bar driven to reciprocate on a vertical axis, a connecting rod for pushing the needle bar, and a driving shaft for driving the connecting rod, the connecting rod has a first end assembled with the driving shaft, and a second end assembled with the needle bar, the first end is moved on a circular trajectory by the driving shaft, the sewing machine structure is characterized in that: The height of the first end of the connecting rod relative to the needle plate is always lower than the height of the second end of the connecting rod relative to the needle plate. When the first end of the connecting rod is displaced counterclockwise from the three o’clock position of the circular trajectory to the twelve o’clock position, the needle bar travels an upstroke displacement distance. The sewing machine structure according to claim 1, wherein the drive shaft has a cam which is combined with the connecting rod, and the cam is formed with an eccentric part which is combined with the first end. The sewing machine structure as described in claim 1 or 2, wherein the sewing machine structure comprises an upper housing and a lower housing connected with the upper housing and providing the needle plate. The upper housing is formed with a chamber, the drive shaft, the connecting rod and the needle bar are assembled in the chamber, and the housing has a track that is arranged in the chamber and higher than the drive shaft to limit the second end to move only along the vertical axis. The sewing machine structure according to claim 3, wherein the chamber is divided into a top and a bottom by a center line, the driving shaft is located at the bottom, and the track is located at the top. The sewing machine structure as described in Claim 4, wherein the sewing machine structure comprises a lower hook located in the lower housing, and a hook drive shaft arranged in the lower housing, the lower hook has a mounting portion assembled with the hook driving shaft, a straight extension extending from the mounting portion, an oblique extension extending from the end of the straight extension not connected to the installation portion, and a hooking portion extending from the oblique extension toward the installation portion. The sewing machine structure as described in claim 3, wherein the sewing machine structure comprises a lower hook located in the lower housing, and a hook drive shaft arranged in the lower housing, the lower hook has a mounting portion assembled with the hook driving shaft, a straight extension extending from the mounting portion, an oblique extension extending from the end of the straight extension not connected to the installation portion, and a hooking portion extending from the oblique extension toward the installation portion.

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