JP5286453B2 - Overlock sewing machine thread tensioner - Google Patents

Description

  The present invention relates to a thread tension device for an overlock sewing machine that can not only collectively adjust thread clamping pressure in each thread tension adjusting mechanism but also finely adjust the thread clamping pressure.

  When sewing with a sewing machine that uses a plurality of sewing threads such as an overlock sewing machine, it is necessary to change the tension applied to each sewing thread in accordance with the type of stitches (overlock sewing, full-winding sewing, decorative sewing, etc.). Further, it is necessary to change the tension applied to each sewing thread depending on the type of thread used, such as spun thread, cotton thread, filament thread or the like.

  In order to allow the user to easily change the tension applied to each sewing thread, a model has been developed in which the tension applied to each sewing thread is collectively changed with a single dial. However, when sewing is actually performed, there may be a slight difference in the thickness of the cloth. Usually, a fine adjustment lever that can finely adjust the tension applied to each sewing thread is provided.

  For example, in Patent Document 1, a thread tension adjusting device for a sewing machine that can simultaneously switch the thread tensions of a plurality of thread tension units with a conversion knob and adjust the thread tension of each thread tension unit with a manual thread tension dial in that state. It is disclosed. Further, in Patent Document 2, there is provided an overlock sewing thread tension device that can adjust the clamping pressure between two thread tension plates supported so as to be slidable in the axial direction to a desired clamping pressure by an end face cam. It is disclosed.

Japanese Patent No. 3046602 Utility Model Registration No. 2584980 JP 2006-087539 A

  However, in the thread tension adjusting device for a sewing machine and the thread tensioner for an overlock sewing machine disclosed in Patent Documents 1 and 2, the end face cam in the thread tension unit and the thread tension plate are integrated, and the conversion knob Due to the urging force of the spring accompanying the rotation, the position of the thread tension plate moves in the axial direction. Therefore, depending on the amount of movement, the tension applied to the sewing thread fluctuates slightly, and there is a problem that fine adjustment of the thread tension by the manual thread tension dial tends to occur.

  In Patent Document 3, the rotation shaft of the cam and the rotation shaft of the thread tension plate are separate, and the thread of the overlock sewing machine does not move in the axial direction when the thread tension is adjusted by turning the selection dial. A tone device is disclosed. However, in the thread tension device of the overlock sewing machine disclosed in Patent Document 3, when the thread tension is finely adjusted, the thread tension tray moves integrally with the thread tension fine adjustment mechanism. Therefore, there is a possibility that the tension applied to the sewing thread slightly fluctuates due to the fine adjustment operation of the thread tension.

  The present invention has been made in view of such circumstances, and is a case where the thread clamping pressure in each thread tension adjusting mechanism can be collectively adjusted with one dial, and the thread clamping pressure is finely adjusted. Another object of the present invention is to provide a thread tension device for an overlock sewing machine in which the position of the thread tension plate is unchanged.

  In order to solve the above-described problem, the thread tension device of the overlock sewing machine according to the first aspect of the present invention provides a plurality of thread tensions, each end of which is pressure-bonded, that applies a thread clamping pressure that is set in accordance with a sewing method to each sewing thread. A plate, a plurality of urging members for urging the yarn clamping pressure for each thread tension plate, and a plurality of end face cams having different shapes that control the urging force of the urging member are coaxially arranged. An operation dial that is arranged and collectively rotates the plurality of end face cams, and is arranged between the thread tension plate and the urging member, and adjusts the urging force of the urging member. The thread tension plate presser gear that can move to the left and right on the same axis is provided, and the rotation shaft is the same as the interlocking gear that interlocks with the operation dial and the adjustment gear that interlocks with the fine adjustment lever that performs fine adjustment. And the first intermediate gear that operates independently And the second intermediate gear, the first intermediate gear meshing with the end face cam and the interlocking gear, and the second intermediate gear meshing with the thread tension plate presser gear and the adjustment gear, respectively. And when the operation dial is operated, the end face cam, the interlocking gear, and the first intermediate gear, and when the fine adjustment lever is operated, the thread tension plate presser gear, the adjustment gear, and the second intermediate gear, Are meshed with each other.

  In the first aspect of the present invention, a plurality of thread tension plates, each of which is press-bonded at one end side, are applied to each sewing thread, and a plurality of thread tensioning pressures are applied to each thread tension plate. And a plurality of end face cams having different shapes that control the biasing force of the biasing member are coaxially arranged, and an operation dial that rotates the plurality of end face cams collectively. I have. As a result, when the end cam is rotated by the operation dial and the thread clamping pressure set for each thread tension tray is adjusted, the position of each thread tension tray may fluctuate because one end side is crimped. There is little possibility that the tension applied to the sewing thread will fluctuate. In addition, a thread tension plate presser gear that is arranged between the thread tension plate and the biasing member and can move left and right on the same axis so as to adjust the biasing force of the biasing member is provided. Thus, the thread clamping pressure can be finely adjusted for each thread tension adjusting mechanism provided for each sewing thread of the thread tensioner, and the thread tension plate does not move even when the thread clamping pressure is finely adjusted. Therefore, there is no possibility that the tension applied to the sewing thread will fluctuate due to the fine adjustment operation of the thread clamping pressure, and the thread clamping pressure can be adjusted with high accuracy. In addition, there are an interlocking gear that interlocks with the operation dial, an adjustment gear that interlocks with the fine adjustment lever that performs fine adjustment, and a first intermediate gear and a second intermediate gear that have the same rotating shaft and operate independently. The first intermediate gear is meshed with the end face cam and the interlocking gear, and the second intermediate gear is meshed with the thread tension plate presser gear and the adjustment gear. At the time of batch adjustment by operation of the operation dial, the end face cam and the interlocking gear and the first intermediate gear mesh with each other, so that the biasing force of the biasing member can be adjusted collectively by the end face cam. On the other hand, at the time of fine adjustment by operating the fine adjustment lever, the thread tension plate presser gear and adjustment gear and the second intermediate gear mesh with each other. Therefore, the thread tension pressure is slightly adjusted for each thread tension adjusting mechanism provided for each thread by the thread tensioner. Can be adjusted.

  The thread tension device of the overlock sewing machine according to the second aspect of the present invention is the first aspect of the invention, wherein the thread tension tray is composed of two plates, and the two plates are in a state where they are pressed against each other. The urging force of the urging member is increased or decreased by the thread tension plate presser gear.

  In the second invention, the thread tension tray is composed of two trays, and the force applied by the biasing member is increased or decreased by the thread tension tray presser gear in a state where the two trays are pressure-bonded to each other. Thus, the thread clamping pressure can be finely adjusted for each thread tension adjusting mechanism, and the thread tension plate does not move even when the thread clamping pressure is finely adjusted. Therefore, there is no possibility that the tension applied to the sewing thread will fluctuate slightly due to the fine adjustment operation of the thread clamping pressure, and the thread clamping pressure can be adjusted with high accuracy.

  According to a third aspect of the present invention, there is provided the thread tension device of the overlock sewing machine according to the first or second aspect, wherein the thread tension plate presser gear is screwed onto a connecting shaft of the thread tension plate presser that is in contact with the thread tension plate. The thread tension plate presser gear is configured to move to the left and right along the connecting shaft of the thread tension plate presser when the thread tension plate presser gear rotates.

  In the third aspect of the invention, the thread tension plate presser gear is screwed to the connecting shaft of the thread tension plate presser that is in contact with the thread tension plate, and the thread tension plate presser gear is rotated to rotate the thread tension plate presser gear. Since it can move left and right along the connecting shaft of the thread tension plate presser, the thread clamping pressure can be finely adjusted for each thread tension adjusting mechanism by rotating the thread tension plate presser gear, and the thread clamping pressure Even when fine adjustment is performed, the thread tension plate does not move. Therefore, there is no possibility that the tension applied to the sewing thread will fluctuate due to the fine adjustment operation of the thread clamping pressure, and the thread clamping pressure can be adjusted with high accuracy.

  According to the present invention, when the end face cam is rotated by the operation dial to adjust the thread clamping pressure set for each thread tension tray, the position of each thread tension tray is fluctuated because one end side is crimped. There is little possibility that the tension applied to the sewing thread will fluctuate. In addition, a thread tension plate presser gear that is arranged between the thread tension plate and the biasing member and can move left and right on the same axis so as to adjust the biasing force of the biasing member is provided. Thus, the thread clamping pressure can be finely adjusted for each thread tension adjusting mechanism provided for each sewing thread of the thread tensioner, and the thread tension plate does not move even when the thread clamping pressure is finely adjusted. Therefore, there is no possibility that the tension applied to the sewing thread will fluctuate due to the fine adjustment operation of the thread clamping pressure, and the thread clamping pressure can be adjusted with high accuracy.

It is a front view which shows the structure of the thread tension device of the overlock sewing machine which concerns on embodiment of this invention. It is a schematic diagram which shows the structure of the connection mechanism of the operation dial of the thread tensioner of the overlock sewing machine which concerns on embodiment of this invention, and a thread tension adjustment mechanism. It is the top view and front view which show the structure of the thread tension adjusting mechanism of the thread tension device of the overlock sewing machine which concerns on embodiment of this invention. It is a right view which shows the structure of the adjustment gear of the thread tension adjusting mechanism of the thread tensioner of the overlock sewing machine which concerns on embodiment of this invention. It is a front view for demonstrating the mechanism part for performing fine adjustment among the thread tension adjustment mechanisms of the thread tension device of the overlock sewing machine which concerns on embodiment of this invention.

  Hereinafter, a thread tension device of an overlock sewing machine according to an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a front view showing a configuration of a thread tensioner of an overlock sewing machine according to an embodiment of the present invention.

  As shown in FIG. 1, the thread tension device 1 of the overlock sewing machine according to the present embodiment includes a thread tension adjusting mechanism 2, 2, 2, 2 for left needle, right needle, upper looper, and lower looper. Are provided on the same axis. The thread tension adjusting mechanisms 2, 2, 2, 2 are sandwiched between the support plates 4, 5 and can rotate in conjunction with the operation dial 3. That is, by rotating the operation dial 3, the thread clamping pressure in each thread tension adjusting mechanism 2 can be adjusted at once.

  FIG. 2 is a schematic diagram showing a configuration of a connection mechanism between the operation dial 3 and the thread tension adjusting mechanism 2 of the thread tension device 1 of the overlock sewing machine according to the embodiment of the present invention. As shown in FIG. 2, a selection gear 31 is connected to the operation dial 3, the selection gear 31 is connected to the interlocking gear 32, and the interlocking gear 32 is connected to the thread tension adjusting mechanism 2 via an intermediate gear 33b. It is.

  FIG. 3 is a plan view and a front view showing the configuration of the thread tension adjusting mechanism 2 of the thread tensioner 1 of the overlock sewing machine according to the embodiment of the present invention. 3A is a plan view of the thread tension adjusting mechanism 2 as viewed from above the overlock sewing machine, and FIG. 3B is a view of the thread tension adjusting mechanism 2 as viewed from the side where the user operates the overlock sewing machine. A front view is shown.

  As shown in FIG. 3, the thread tension adjusting mechanism 2 has a thread tension tray 21 sandwiching the sewing thread, which is crimped to one end side. The thread tension tray 21 is composed of symmetrical plates 21a and 21b that are opposed to each other, and the other tray 21b is pressure-bonded to one tray 21a by a biasing force.

  A base plate 22 is provided on the other end side of the thread tension adjusting mechanism 2, and the base plate 22 is provided with a protrusion 23 that controls the operation of the end face cam 24. The shape of the end face cam 24 is changed for each thread tension adjusting mechanism 2. As the operation dial 3 rotates, the interlocking gear 32 and the intermediate gear 33b rotate, and the end face cam 24 of the thread tension adjusting mechanism 2 connected to the intermediate gear 33b rotates.

  As the end face cam 24 rotates, the contact position with the protrusion 23 changes, and the end face cam 24 moves in the direction of the rotation axis, that is, in the direction of the arrow in FIG. Moving. In accordance with the movement of the end face cam 24, the urging force of the compression spring (biasing member) 25 to the thread tension tray presser gear 26 and the thread tension tray presser 27 varies. That is, the end face cam 24 moves to the left as the end face cam 24 and the projection 23 come into contact with each other at a shallow position on the end face of the end face cam 24, and the thread tension plate presser gear 26 of the compression spring (biasing member) 25. And the urging | biasing force to the thread tension plate presser 27 which can move along a rotating shaft without rotating becomes large. Accordingly, since the pressing force by which the thread tension tray presser 27 presses the other tray 21b of the thread tension tray 21 against the one tray 21a increases, the thread clamping pressure for sandwiching the sewing thread in the thread tension tray 21 increases.

  On the other hand, the end face cam 24 moves to the right as the end face cam 24 and the protrusion 23 come into contact with each other at a deeper position on the end face of the end face cam 24, and the thread tension plate presser gear 26 of the compression spring (biasing member) 25. And the urging force to the thread tension plate presser 27 is reduced. Accordingly, since the pressing force by which the thread tension tray presser 27 presses the other tray 21b of the thread tension tray 21 against the one tray 21a is reduced, the thread clamping pressure for sandwiching the sewing thread in the thread tension tray 21 is reduced. By designing the shape of the end face cam 24 so that a desired thread clamping pressure is generated according to the rotation of the operation dial 3, a plurality of thread tensions composed of two plates are obtained by rotating the operation dial 3. The thread clamping pressure for clamping the sewing thread in the plates 21, 21, 21, and 21 can be collectively adjusted.

  Moreover, not only the adjustment in a lump, but also the thread clamping pressure for clamping the sewing thread in each thread tension tray 21 can be finely adjusted. In the present embodiment, the intermediate gear 33a and the intermediate gear 33b are gears that operate separately and independently, and only have the same rotation axis. When finely adjusting the thread clamping pressure for clamping the sewing thread in the thread tension tray 21, only the thread tension tray presser gear 26 is rotated via the intermediate gear 33a by rotating the adjustment gear 30.

  A thread is formed on the inner diameter of the thread tension plate presser gear 26 and is threadedly engaged with a thread on the surface of the connecting shaft 271 connected to the thread tension plate presser 27. That is, by forming a female screw on the inner diameter of the thread tension plate presser gear 26 and forming a male screw on the surface of the connecting shaft 271 of the thread tension plate presser 27, the thread tension plate presser gear 26 is rotated. The thread tension plate presser gear 26 moves in the direction of the connecting shaft 271 (left and right direction). As a result, the biasing force of the compression spring (biasing member) 25 to the thread tension plate presser 27 can be increased or decreased.

  FIG. 4 is a right side view showing the configuration of the adjustment gear 30 of the thread tension adjusting mechanism 2 of the thread tension device 1 of the overlock sewing machine according to the embodiment of the present invention. The adjustment gear 30 is formed integrally with the adjustment lever 30a. By rotating the adjustment lever 30a in the vertical (arrow) direction, the intermediate gear 33a rotates and the thread tension plate presser gear 26 rotates.

  FIG. 5 is a front view for explaining a mechanism part for performing fine adjustment in the thread tension adjusting mechanism 2 of the thread tensioner 1 of the overlock sewing machine according to the embodiment of the present invention. FIG. 5 shows a front view of the thread tension adjusting mechanism 2 as viewed from the side on which the user operates the overlock sewing machine.

  As shown in FIG. 5, the adjustment gear 30 rotates in accordance with the upward or downward rotation operation of the adjustment lever 30a shown in FIG. As the adjustment gear 30 rotates, the thread tension plate presser gear 26 rotates via the intermediate gear 33a.

  The thread tension plate presser gear 26 is screwed with a thread on the surface of the connecting shaft 271 connected to the thread tension plate presser 27. Therefore, by rotating the thread tension plate presser gear 26, the position of the thread tension plate presser gear 26 moves in the connecting shaft direction (left-right direction). When the thread tension plate presser gear 26 moves rightward along the connecting shaft 271, the compression spring (biasing member) 25 is compressed, and the biasing force to the thread tension plate presser 27 increases. On the contrary, when the thread tension plate presser gear 26 moves to the left along the connecting shaft 271, the compression spring (biasing member) 25 is extended, and the biasing force to the thread tension plate presser 27 is reduced.

  When the urging force to the thread tension tray presser 27 increases, the pressing force of the thread tension tray presser 27 pressing the other tray 21b of the thread tension tray 21 against the one tray 21a increases, so that the sewing thread on the thread tension tray 21 is increased. The thread clamping pressure for sandwiching the thread increases. When the urging force to the thread tension tray presser 27 is reduced, the pressing force of the thread tension tray presser 27 pressing the other tray 21b of the thread tension tray 21 against the one tray 21a is reduced, so that the sewing thread in the thread tension tray 21 is reduced. The thread clamping pressure for sandwiching the thread is reduced.

  As described above, according to the present embodiment, when the end face cam 24 is rotated by the operation dial 3 and the thread clamping pressure set for each thread tension tray 21 is adjusted, each thread tension tray 21 is Since the one end side is crimped, the position does not change, and the tension applied to the sewing thread is less likely to change. Further, a thread tension plate presser gear which is arranged between the thread tension plate 21 and the biasing member 25 and can move left and right on the same axis so as to adjust the biasing force of the biasing member 25. 26, the thread tensioning plate 21 can finely adjust the thread clamping pressure for each thread tension adjusting mechanism 2 provided for each sewing thread, and the thread tension tray 21 even when the thread clamping pressure is finely adjusted. Does not move. Therefore, there is no possibility that the tension applied to the sewing thread will fluctuate due to the fine adjustment operation of the thread clamping pressure, and the thread clamping pressure can be adjusted with high accuracy.

  In addition, various modifications can be added to the above-described embodiment without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 1 Thread tension device 2 Thread tension adjustment mechanism 3 Operation dial 21 Thread tension tray 21a One tray 21b The other tray 23 Projection part 24 End surface cam 25 Compression spring (biasing member)
26 Thread tension plate presser gear 27 Thread tension plate presser 30 Adjustment gear 30a Adjustment lever 33a, 33b Intermediate gear 271 Connecting shaft

Claims (3)

A plurality of thread tension plates each of which is crimped on one end side, each of which applies a thread clamping pressure set in accordance with the sewing method,
A plurality of biasing members for biasing the thread clamping pressure for each thread tension plate;
A plurality of end face cams having different shapes, which control the biasing force of the biasing member, are arranged coaxially;
An operation dial for collectively rotating the plurality of end face cams;
A thread tension plate presser gear, which is arranged between the thread tension plate and the biasing member and can move left and right on the same axis so as to adjust the biasing force of the biasing member. Prepared,
An interlocking gear interlocking with the operation dial;
An adjustment gear linked to a fine adjustment lever for fine adjustment,
Having a first intermediate gear and a second intermediate gear that have the same rotation axis and operate independently;
The first intermediate gear is meshed with the end face cam and the interlocking gear, and the second intermediate gear is meshed with the thread tension plate presser gear and the adjustment gear, respectively.
When the operation dial is operated, the end face cam, the interlocking gear, and the first intermediate gear are used.When the fine adjustment lever is operated, the thread tension plate presser gear, the adjustment gear, and the second intermediate gear are used. Overlock sewing machine thread tensioner characterized by engaging each other. The thread tension plate is composed of two plates,
2. The overlock sewing machine according to claim 1, wherein the biasing force of the biasing member is increased or decreased by the thread tension tray presser gear in a state where the two trays are pressure-bonded to each other. Thread tensioner.   The thread tension plate presser gear is screwed into a connecting shaft of a thread tension plate presser that is in contact with the thread tension plate, and the thread tension plate presser gear is rotated by rotating the thread tension plate presser gear. 3. A thread tensioner for an overlock sewing machine according to claim 1, wherein the thread tensioner is moved left and right along the connecting shaft of the thread tension plate presser.

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