JP7388809B2 - Feed-out arm type double chainstitch sewing machine - Google Patents

Description

The present invention relates to a feed-out arm type double chainstitch sewing machine that includes an arm portion on the sewing machine bed portion that extends in the cloth presser feed direction.

Conventionally, a so-called feed-out arm type double ring has been used, in which the sewing machine bed is formed into a U-shape in plan view, an arm is provided along the cloth feeding direction, and a needle plate is provided at the tip of the arm for sewing. A sewing machine is used.
As shown in FIG. 5, this feed-out arm type double chainstitch sewing machine 100 has a sewing machine frame 101 composed of a sewing machine bed section 110, a vertical body section 102, and a sewing machine arm section 103. A first extending portion 111 extends from below 102 toward the upstream side in the cloth feeding direction, and a second extending portion 112 extends from the tip of the first extending portion 111 in the same direction as the sewing machine arm portion 103. and a third extending portion 113 extending from the tip of the second extending portion 112 to the downstream side in the cloth feeding direction.
Rotational force is input from a sewing machine motor (not shown) to an upper shaft provided on the sewing machine arm section 103, and a timing belt extending diagonally from the upper shaft is input to a lower shaft provided on the second extension section 112. Rotational force is transmitted through the Reference numeral 104 in FIG. 5 is a belt cover in which a timing belt is housed (see, for example, FIG. 2 of Patent Document 1).

In addition, other feed-out arm type double chainstitch sewing machines are equipped with a sewing machine bed section having the same shape as shown in FIG. It is spanned in a bent manner along the

Japanese Patent Application Publication No. 04-026458

However, in the above-mentioned conventional feed-out arm type double chainstitch sewing machine, the length of the timing belt is extremely long because the timing belt is stretched from the upper shaft to the lower shaft in an oblique direction or along a curved path. The influence of the elongation becomes large, and there is a risk that the amount of rotation between the upper shaft and the lower shaft will be misaligned, resulting in skipped stitches, etc. during sewing.
For example, when skipped stitches occur, it is difficult to re-stitch from the middle, so re-sewing from the beginning is forced, which poses a problem that greatly impairs work efficiency.
In addition, the timing belt, which is stretched diagonally from the upper shaft to the lower shaft, and the belt cover that stores the belt, are arranged to block the space for handling the sewing product.

SUMMARY OF THE INVENTION An object of the present invention is to provide a feed-out arm type double chainstitch sewing machine that can stably form stitches.

The invention according to claim 1 is
It has a sewing machine frame having a sewing machine bed part, a vertical body part, and a sewing machine arm part,
The sewing machine bed section includes a first extension section extending from below the vertical body section toward an upstream side in the cloth feeding direction, and a first extension section extending from a tip end of the first extension section in the same direction as the sewing machine arm section. A feed-out arm type double chainstitch sewing machine having a second extending portion, and a third extending portion extending downstream in the cloth feeding direction from a distal end portion of the second extending portion,
an upper shaft provided on the sewing machine arm;
a lower shaft provided in the second extension part of the sewing machine bed part;
an intermediate shaft provided below the vertical body part in the first extending part of the sewing machine bed part;
a sewing machine motor that inputs rotational force to the intermediate shaft;
a single first timing belt that transmits rotational force from the intermediate shaft to the upper shaft;
a single second timing belt that transmits rotational force from the intermediate shaft to the lower shaft ,
The sewing machine motor is directly connected to the intermediate shaft so as to rotate concentrically and simultaneously .

The invention according to claim 2 provides a feed-out arm type double chainstitch sewing machine according to claim 1, comprising:
The first timing belt and the second timing belt are belts of the same length.

Even when the upper shaft and lower shaft are placed apart from each other, such as in a feed-out arm type double chainstitch sewing machine, the present invention provides an intermediate shaft and transmits rotational force from the intermediate shaft to the upper shaft using the first timing belt. Since the configuration is such that a second timing belt transmits rotational force from the intermediate shaft to the lower shaft, each timing belt can be shortened and the influence of timing belt elongation can be reduced. It is possible to reduce the deviation in the amount of rotation between the two, thereby suppressing the occurrence of skipped stitches and the like.
Therefore, it becomes possible to form stitches stably.

1 is a perspective view of a feed-out arm type double chainstitch sewing machine according to an embodiment of the invention. FIG. 3 is a perspective view showing the right end of the sewing machine frame with the belt cover and motor cover removed. FIG. 2 is a perspective view showing the right end of the sewing machine frame with the belt cover, motor cover, and motor base removed. FIG. 3 is a sectional view taken along the intermediate axis of the first extending portion of the sewing machine bed portion. FIG. 1 is a perspective view of a conventional feed-out arm type double chainstitch sewing machine.

[Schematic configuration of embodiment]
EMBODIMENT OF THE INVENTION Hereinafter, the feed-out arm type double chainstitch sewing machine 10 which is an embodiment of this invention will be described in detail.
FIG. 1 is a perspective view of a feed-out arm type double chainstitch sewing machine 10. As shown in FIG.
A feed-out arm type double chainstitch sewing machine 10 according to an embodiment of the present invention includes a sewing machine frame 20 and a cloth that is pressed from above by a cloth presser against a sewing workpiece on the upper surface of a throat plate 11 provided on a sewing machine bed section 30, which will be described later. a presser mechanism, a needle up-and-down movement mechanism for causing a sewing needle to drop onto a workpiece on the throat plate 11, and a cloth that feeds the workpiece from the lower side of the throat plate 11 in a predetermined cloth feeding direction using a feed dog. A feeding mechanism, a looper mechanism that entwines the looper thread with the upper thread of the sewing needle, and a cloth pulling roller mechanism that feeds the workpiece by rotating a roller separate from the fabric feeding mechanism on the downstream side of the fabric holder in the fabric feeding direction. 40, a thread take-up mechanism for pulling up the upper thread, a thread tensioner for applying tension to the upper thread, and a transmission mechanism 50 for transmitting power from the sewing machine motor 12 to various parts. Note that the other configurations except for the sewing machine frame 20 and the transmission mechanism 50 are the same as the well-known configuration of a feed-out arm type double chainstitch sewing machine, so illustrations and detailed explanations will be omitted.

[Sewing machine frame]
The sewing machine frame 20 includes a sewing machine bed section 30 located at the lower part of the entire feed-out arm type double chainstitch sewing machine 10, a vertical body section 21 erected upward at one end of the sewing machine bed section 30, and a vertical body section 21 that stands upwardly at one end of the sewing machine bed section 30. A sewing machine arm part 22 extending in a predetermined direction from the upper end of the part 21, a belt cover 23 that covers the transmission mechanism 50 on the right side of the vertical body part 21 and the sewing machine bed part 30, and a motor cover 24 that covers the sewing machine motor 12. It is equipped with
Hereinafter, the horizontal direction parallel to the longitudinal direction of the sewing machine arm section 22 will be referred to as the Y-axis direction, the surface side of the sewing machine arm section 22 will be referred to as "left", and the side of the vertical body section 21 will be referred to as "right". Further, the horizontal direction and the direction orthogonal to the Y-axis direction is defined as the X-axis direction. This X-axis direction is parallel to the feeding direction of the workpiece by the feed-out arm type double chainstitch sewing machine 10, and the downstream side in the feeding direction of the workpiece is referred to as "front" and the upstream side as "rear". Further, a direction perpendicular to the X-axis direction and the Y-axis direction is referred to as the Z-axis direction, and one of them is referred to as "upper" and the other is referred to as "lower."

The sewing machine bed section 30 also includes a first extending section 31 extending from below the vertical body section 21 toward the upstream side (rearward) in the cloth feeding direction, and a sewing machine arm section extending from the tip of the first extending section 31. 22, and a third extending portion 33 extending downstream (forward) in the cloth feeding direction from the tip of the second extending portion 32. It has
Since the sewing machine bed section 30 is used as a workbench for the workpiece, the upper surfaces of the first to third extending sections 31 to 33 are connected to each other on the same plane along the XY plane. The entire structure is flat.
Further, at the upper part of the front end of the third extending portion 33, a needle plate 11 is provided which is flush with the upper surfaces of the first to third extending portions 31 to 33.

[Needle vertical movement mechanism]
The needle vertical movement mechanism includes an upper shaft 61 (see FIG. 2) that receives rotational force from the sewing machine motor 12 via a transmission mechanism 50, a needle bar that holds the sewing needle at its lower end, and a needle vertical movement mechanism that transmits the rotational force of the upper shaft 61 up and down. It is equipped with a crank mechanism that converts the reciprocating driving force into reciprocating driving force and transmits it to the needle bar.
The upper shaft 61 is rotatably supported inside the sewing machine arm portion 22 along the Y-axis direction.

[Looper mechanism]
The looper mechanism includes a looper provided below the throat plate 11 and a swinging mechanism that swings the tip of the looper along the Y-axis direction.
A looper thread is inserted through a threading hole in a sharp tip of the looper. Then, the looper advances toward the left with respect to the sewing needle rising under the throat plate, inserting the looper thread into the loop of the needle thread, and retreats toward the right to move the looper. A loop is formed in the thread, and the next needle entry causes the sewing needle to enter the loop of the looper thread. By repeating these operations, loops of the looper thread and loops of the needle thread are alternately inserted to form a knot.

The swing mechanism includes a lower shaft 62 (see FIG. 2) that receives rotational force from the sewing machine motor 12 via a transmission mechanism 50, and a transmission member that converts the full rotation of the lower shaft 62 into reciprocating rotation and transmits it to each looper. These move the looper forward along the Y-axis direction.
The lower shaft 62 is rotatably supported inside the second extending portion 32 of the sewing machine bed portion 30 along the Y-axis direction.

[Cloth feeding mechanism]
The cloth feed mechanism includes a feed dog that protrudes and retracts from an opening (not shown) of the throat plate 11, and a feed transmission mechanism that combines and transmits a reciprocating motion in the Z-axis direction and a reciprocating motion in the X-axis direction to the feed dog. We are prepared.
The feed dog has serrated teeth that appear and retract from a slit-shaped opening formed in the throat plate 11 along the X-axis direction, and combines reciprocating motion in the Z-axis direction and reciprocating motion in the X-axis direction. When moving in the upper part of the ellipse, the tip of the tooth protrudes upward from the opening and moves forward, making it possible to feed the workpiece forward.
The feed transmission mechanism converts the full rotation of the lower shaft 62 described above into a reciprocating motion along the X-axis direction and a reciprocating motion along the Z-axis direction and transmits it to the feed dog, thereby imparting an elliptical motion to the feed dog. is granted.

[Transmission mechanism]
2 is a perspective view showing the right end of the sewing machine frame 20 with the belt cover 23 and motor cover 24 removed, FIG. 3 is a perspective view of the sewing machine frame 20 with the motor base 51, which will be described later, removed, and FIG. 4 is the sewing machine bed. 30 is a cross-sectional view taken along an intermediate axis 52 (described later) of the first extending portion 31 of No. 30. FIG.

The transmission mechanism 50 includes a motor base 51 that supports the sewing machine motor 12, an intermediate shaft 52 that receives rotational force from the sewing machine motor 12, an intermediate shaft sprocket 53 provided on the intermediate shaft 52, and an upper shaft 61. the upper shaft sprocket 54, the lower shaft sprocket 55 provided on the lower shaft 62, the first timing belt 56 that is stretched from the intermediate shaft sprocket 53 to the upper shaft sprocket 54, and the lower shaft sprocket from the intermediate shaft sprocket 53. 55 and a second timing belt 57 that is stretched around the timing belt 55.

The intermediate shaft 52 is supported along the Y-axis direction at the front end of the first extending portion 31 of the sewing machine bed portion 30 and directly below the vertical body portion 21 .
This intermediate shaft 52 is rotatably supported around the Y-axis by two bearings 521 disposed inside the first extension part 31 at its left end and longitudinally intermediate part, and at its right end. It protrudes to the right from one extension part 31.
Further, the right end portion of the intermediate shaft 52 is connected to the output shaft of the sewing machine motor 12, and an intermediate shaft sprocket 53 is provided between the sewing machine motor 12 and the first extension portion 31. The intermediate shaft sprocket 53 is fixedly connected to the intermediate shaft 52, and the intermediate shaft sprocket 53 and the intermediate shaft 52 rotate integrally.

The motor base 51 is fixedly mounted on the right end surface of the first extension portion 31, and the aforementioned intermediate shaft 52 passes through the motor base 51. A bearing 511 that rotatably supports the intermediate shaft 52 is also provided inside the motor base 51.
Furthermore, the motor base 51 fixedly supports the sewing machine motor 12 at its right end. The sewing machine motor 12 is supported by a motor base 51 so that its output shaft is directed leftward and is concentric with the intermediate shaft 52 described above.
The output shaft of the sewing machine motor 12 and the right end of the intermediate shaft 52 are connected by a coupling 512.
As a result, rotational force is directly input to the intermediate shaft 52 and the intermediate shaft sprocket 53 from the sewing machine motor 12.

The above-mentioned upper shaft 61 is installed with its right end projecting rightward from the right end of the sewing machine arm section 22, and the upper shaft sprocket 54 is installed at the right end of the upper shaft 61. The upper shaft sprocket 54 is fixedly connected to the upper shaft 61, and the upper shaft sprocket 54 and the upper shaft 61 rotate integrally.

The lower shaft 62 mentioned above is installed with its right end protruding rightward from the right end of the second extension 32 of the sewing machine bed section 30, and the lower shaft sprocket 55 is attached to the right end of the lower shaft 62. Equipped. The lower shaft sprocket 55 is fixedly connected to the lower shaft 62, and the lower shaft sprocket 55 and the lower shaft 62 rotate integrally.

Both the first timing belt 56 and the second timing belt 57 are endless annular belts, and the same belts having the same length are used. That is, the respective arrangements are set so that the distance between the intermediate shaft 52 and the upper shaft 61 and the distance between the intermediate shaft 52 and the lower shaft 62 are equal.
The intermediate shaft sprocket 53, the upper shaft sprocket 54, and the lower shaft sprocket 55 are all toothed sprockets, and the first timing belt 56 and the second timing belt 57 are toothed belts. Therefore, the teeth of each of the sprockets 53 to 55 and each of the timing belts 56, 57 mesh with each other, allowing accurate transmission of rotation.

The transmission mechanism 50 also includes a tension roller (not shown) that presses the first timing belt 56 tensioned between the intermediate shaft sprocket 53 and the upper shaft sprocket 54 inward at position a, and a tension roller (not shown) that presses the first timing belt 56 tensioned between the intermediate shaft sprocket 53 and the upper shaft sprocket 54, and between the intermediate shaft sprocket 53 and the lower shaft sprocket. 55 and a tension roller (not shown) that presses the second timing belt 57 stretched inward at position b.
As a result, the slack in each timing belt 56, 57 can be eliminated, and the range in which each timing belt 56, 57 meshes with each sprocket 53 to 55 can be made larger than 180°, reducing the occurrence of tooth skipping. Rotation can be transmitted more accurately.

[Operation of transmission mechanism]
In the transmission mechanism 50 having the above configuration, rotational force is input to the intermediate shaft 52 when the sewing machine motor 12 is driven.
Then, the rotational force is transmitted from the intermediate shaft sprocket 53 to the upper shaft sprocket 54 via the first timing belt 56, and the upper shaft 61 rotates.
As a result, the needle up and down movement mechanism moves the sewing needle up and down.
Further, rotational force is transmitted from the intermediate shaft sprocket 53 to the lower shaft sprocket 55 via the second timing belt 57, and the lower shaft 62 rotates.
As a result, the looper mechanism swings the looper, and the cloth feeding mechanism executes the feeding operation of the feeding dog.
Therefore, the sewing needle and the looper work together to form a double chain stitch, and the feed dog feeds the workpiece at a predetermined sewing pitch to execute the double chain stitch.

[Technical effects of embodiments of the invention]
In the above-mentioned sending arm type double chainstitch sewing machine 10, an intermediate shaft 52 is provided below the vertical trunk section 21 in the first extending section 31 of the sewing machine bed section 30, and the intermediate shaft 52 is connected to the intermediate shaft 52 via the first timing belt 56. The rotational force is transmitted from the intermediate shaft 52 to the upper shaft 61 via the second timing belt 57, and the rotational force is transmitted from the intermediate shaft 52 to the lower shaft 62 via the second timing belt 57.
This makes it possible to shorten each of the timing belts 56 and 57 and reduce the influence of elongation of the timing belts 56 and 57, thereby reducing the discrepancy in the amount of rotation between the upper shaft 61 and the lower shaft 62. Occurrence of flying, etc. can be suppressed. Therefore, it becomes possible to form stitches stably.
In particular, in the case of the feed-out arm type double chainstitch sewing machine 10, by reducing the occurrence of skipped stitches, it is possible to reduce the frequency of re-stitching and improve productivity.

Furthermore, since the first timing belt 56 and the second timing belt 57 are the same belt with the same length, the amount of elongation of the first timing belt 56 and the second timing when the sewing machine motor 12 is driven are different. The difference in the amount of elongation of the belt 57 can be further reduced, and the occurrence of skipped stitches and the like can be suppressed, making it possible to form seams more stably.

[others]
In the feed-out arm type double chainstitch sewing machine 10, the sewing machine motor 12 is directly connected to the intermediate shaft 52 so as to rotate concentrically and simultaneously, but the invention is not limited thereto.
For example, the sewing machine motor 12 is arranged below the table on which the feed-out arm type double chainstitch sewing machine 10 is installed, the output shaft and the intermediate shaft 52 of the sewing machine motor 12 are equipped with pulleys, and a transmission belt such as a V-belt is installed. A configuration may also be adopted in which rotational force is input from the sewing machine motor 12 to the intermediate shaft 52.

In addition, although the above-mentioned sending arm type double chainstitch sewing machine 10 is equipped with the cloth pulling roller mechanism 40, this cloth pulling roller mechanism 40 is not essential, and the cloth pulling roller mechanism 40 is not provided. However, it is possible to perform double chainstitching.

10 Feed-off arm type double chainstitch sewing machine 11 Throat plate 12 Sewing machine motor 20 Sewing machine frame 21 Vertical body section 22 Sewing machine arm section 23 Belt cover 24 Motor cover 30 Sewing machine bed section 31 First extension section 32 Second extension section 33 Three extensions 50 Transmission mechanism 52 Intermediate shaft 53 Intermediate sprocket 54 Upper shaft sprocket 55 Lower shaft sprocket 56 First timing belt 57 Second timing belt 61 Upper shaft 62 Lower shaft 512 Coupling C workpiece

Claims (2)

It has a sewing machine frame having a sewing machine bed part, a vertical body part, and a sewing machine arm part,
The sewing machine bed section includes a first extension section extending from below the vertical body section toward an upstream side in the cloth feeding direction, and a first extension section extending from a tip end of the first extension section in the same direction as the sewing machine arm section. A feed-out arm type double chainstitch sewing machine having a second extending portion, and a third extending portion extending downstream in the cloth feeding direction from a distal end portion of the second extending portion,
an upper shaft provided on the sewing machine arm;
a lower shaft provided in the second extension part of the sewing machine bed part;
an intermediate shaft provided below the vertical body part in the first extending part of the sewing machine bed part;
a sewing machine motor that inputs rotational force to the intermediate shaft;
a single first timing belt that transmits rotational force from the intermediate shaft to the upper shaft;
a single second timing belt that transmits rotational force from the intermediate shaft to the lower shaft ,
A feed-out arm type double chainstitch sewing machine, wherein the sewing machine motor is directly connected to the intermediate shaft so as to rotate concentrically and simultaneously . 2. The feed-out arm type double chainstitch sewing machine according to claim 1, wherein the first timing belt and the second timing belt are belts of the same length.

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