JPH0532072Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention is applied to a sewing machine, and includes an inner hook for storing a bobbin thread, and an outer hook for intertwining the bobbin thread pulled out from the inner hook with the upper thread. The present invention relates to a rotary kettle provided with a kettle.

[Prior Art] The suturing motion of a sewing machine involves the point of a needle provided on the outer hook of a rotary hook getting into a loop of the needle thread that is generated when the needle thread is positioned below the object to be sewn as the needle moves up and down. By rotating the tip, the lower thread is passed through the upper thread when the upper thread is routed around the rotary hook.

By the way, as shown in FIG. 6, the inner hook 100 of the rotary hook of the sewing machine has a notch 106 formed in the upright wall surface 102 through which the bobbin thread wound around the bobbin case 104 housed in the inner hook 100 is pulled out. There is.

However, after the point of an outer hook (not shown) disposed outside the inner hook 100 enters the needle thread loop located below the object to be sewn as the needle moves downward, the rotation of the outer hook causes the When the outer hook rotates with the needle thread held at the tip, the intermediate portion of the needle thread held at the tip may get caught in the notch 106 of the inner hook 100.

In this case, it becomes difficult for the needle to properly pull up the needle thread, causing thread entanglement, thread skipping, thread breakage, etc., which in turn becomes a factor that impedes productivity in the sewing process.

[Problems to be Solved by the Invention] Taking the above facts into consideration, the object of the present invention is to provide a rotary hook for a sewing machine that can prevent the upper thread from getting caught.

[Means for Solving the Problems] The present invention provides a rotary hook for a sewing machine that includes an outer hook that rotates in response to a driving force, and an inner hook that is housed in the outer hook with a bobbin case built-in. The present invention is characterized in that the inner hook is provided with a cantilever-shaped entanglement prevention member that covers, at intervals, an entrance portion of a notch through which the bobbin thread wound around the bobbin case is pulled out from the inner hook.

[Function] In this way, a cantilever-shaped entanglement prevention member is provided that covers the entrance of the notch through which the bobbin thread wound around the bobbin case housed in the inner hook is pulled out from the inner hook when the sewing machine is in operation. Therefore, even when the upper thread is pulled by the tip of the outer hook and rotates around the outer hook, the tangle prevention member prevents the upper thread from entering the notch even if the upper thread corresponds to the notch of the inner hook. The upper thread is properly pulled onto the needle because it does not pull or sag on the notch in the hook.

[Embodiment] Figs. 1 to 5 show an embodiment of a rotary hook of a sewing machine according to the present invention.

FIG. 5 shows a partial perspective view of a sewing machine 10 to which a rotary hook of a sewing machine according to the present invention is applied.

As shown in FIG. 5, at one end of the cantilevered arm body 12 of the sewing machine 10 is a bobbin 1 having a needle thread 14 wound thereon.
Two threads 6 are supported, and these windings 16 can be rotated about their shafts by pulling out the upper thread 14.

Further, a thread tension device 18 for pulling out the upper thread 14 is provided on the side surface 12A of the other end of the arm body 12. This thread tension device 18 is connected to the guide hole 20,
20, a plurality of cylindrical protrusions 24, and a guide plate 26. Therefore, the needle thread 14 pulled out from the bobbin 16 passes through the guide hole 20 of the bending plate 22 and is guided upward along the outer circumferential surface of the protrusion 24. After that, the needle thread 14 is guided upwardly along the outer peripheral surface of the protrusion 24 after passing through the guide hole 20 of the bending plate 22. The needle 30 is guided through the guide plate 28 and into the needle hole 32 formed at the tip of the needle 30.

Two needles 30 are provided and are fixed to a needle bar 31 that reciprocates in the vertical direction by a drive device (not shown) built into the sewing machine body 12. Therefore,
As the needle bar 31 reciprocates, the needle 30 also reciprocates in the vertical direction.

Further, from the other end of the arm body 12, a presser plate 34 is provided.
hangs down, and a flat presser portion 36 formed at the tip of the presser plate 34 presses the object to be sewn. Elongated holes 38 are formed in the portions of the presser portion 36 corresponding to the needles 30, respectively, so that the tip portions of the needles 30 can pass therethrough.

A rectangular opening 42 is formed in the bed 40 that constitutes the sewing machine 10 together with the arm body 12.
This opening 42 is located at the throat plate 4 disposed in the middle of the opening 42.
3, and a rotary hook 44 is disposed in each of the divided openings 42. An opening (not shown) is formed in the needle plate 43 so that the needle 30 can pass therethrough. Also,
A feed mechanism 45 is formed on the throat plate 48 so that the object to be sewn can be moved little by little during operation of the sewing machine.

As shown in FIG. 3, the rotary hook 44 has an outer hook 46.
It consists of 50 inner pots. The outer hook 46 is rotated around a vertical axis (in the direction of arrow A in FIG. 4) by a driving means (not shown). A recess 48 having a circular shape in plan view is formed in the outer hook 46, and an inner hook 50 is coaxially disposed in the recess 48 and is rotatable around the axis.

Further, a sharp tip portion 47 is formed on the side surface of the outer hook 46. The tip portion 47 locks the needle thread 14 by entering the loop of the needle thread 14 formed below the object to be sewn, and rotates the needle thread 14 around the outer hook 46 as the outer hook 46 rotates. I'm starting to let them do it.

As shown in FIG. 1, the inner hook 50 has a substantially cylindrical shape, and a cylindrical recess 52 is formed along the axial direction. A bobbin case 56 on which a bobbin thread 54 is wound is housed in the recess 52. Medium pot 50
A bobbin case holding rod 58 is attached to the axial center of the recess 52.
is provided in a protruding manner, and the bobbin case holding rod 58 is inserted into the shaft center through hole 60 of the bobbin case 56 when the bobbin case 56 is accommodated in the recess 52 . Further, a bobbin case holding piece 62 is attached to the tip of the bobbin case holding rod 58.
The bobbin case 5 is attached so as to be bendable at substantially right angles to the axial direction of the bobbin case 8 and housed in the recess 52.
6 is prevented from falling out.

In addition, as shown in FIGS. 1 and 2, the inner pot 50
A notch 66 is formed in the upper edge 64A (one end in the axial direction) of the side surface 64 when viewed from the radial direction. The middle portion and lower end portion of this notch portion 66 are closed by a leaf spring 65 provided on the side surface 64 of the inner hook 50. Further, the upper end of the notch 66 serves as a passage for pulling out the bobbin thread 54 wound around the bobbin case 56. On the upper edge 64A of the side surface 64 in the vicinity of the notch 66, there is provided a cantilever-supported yarn entanglement prevention member 68 that covers the entrance of the notch 66 with its intermediate portion spaced a short distance from the entrance. .

As shown in FIG. 2, this thread entanglement prevention member 68 is approximately parallel to and in a non-contact state with the upper edge 64A of the side surface 64 of the inner hook 50, except for the vicinity of the attachment portion to the side surface 64, and is in a non-contact state. When the bobbin thread 54 is cut, the operator can easily pull out the bobbin thread 54 through the gap and notch 66 between the thread entanglement prevention member 68 and the upper edge 64A.

Next, the operation of the above embodiment will be explained.

After the object to be sewn consisting of two pieces of cloth or the like to be sewn together is placed on the throat plate 43, the drive device of the sewing machine 10 is driven. As a result, the needle bar 31 moves up and down, so that the needle 30 fixed to the needle bar 31 also moves up and down. When the tip of the needle 30 passes through the object to be sewn, the needle thread 14 passing through the needle hole 32 formed at the tip of the needle 30 also passes through the object to be sewn. Then, as the needle 30 moves upward, the needle thread 14 is loosened, and the needle thread 14 below the sewing object is loosened.
creates a small loop. Then, the tip 47 of the outer hook 46, which rotates in response to the driving force, enters the loop. Therefore, the needle thread 14 rotates as the outer hook 46 rotates. At the same time, bobbin case 5
The bobbin thread 54 wound around the hook 6 is inserted into the notch 6 of the inner hook 50.
6, passes through the upper thread 14, and stitches the object to be sewn by the cooperation of the upper thread 14 and the lower thread 54.

By the way, when the upper thread 14 is routed around the rotary hook 44 by the point 47 of the outer hook 46, the middle part of the upper thread 14 touches the upper surface of the inner hook 50 as shown in FIG. A thread entanglement prevention member 6 is attached to the notch 66 formed in the hook 50 so as to cover the entrance of the notch 66.
8 is provided.

Therefore, even if the upper thread 14 rotates as the outer hook 46 rotates and touches the upper surface of the inner hook 50, the thread entanglement prevention member 68 prevents the thread from getting caught in the notch formed in the inner hook 50. There is no such thing as entering or pulling on the portion 66. For this reason, the needle 30
Since the needle thread 14 can be properly pulled upward, thread entanglement, thread skipping, thread breakage, etc. can be prevented.

[Effects of the invention] As explained above, in the rotary hook of the sewing machine according to the present invention, even if the upper thread rotates according to the outer hook, the tangle prevention member prevents it from being caught at the entrance of the notch of the inner hook. This has the effect of improving productivity in the sewing process.

[Brief explanation of the drawing]

1 to 5 show an embodiment of the rotary hook of a sewing machine according to the present invention, FIG. 1 is an overall perspective view of the inner hook and bobbin case, FIG. 2 is a side view of the inner hook, and FIG. 3 is a side view of the inner hook.
The figure is an overall perspective view of the outer hook with the inner hook accommodated, FIG. 4 is an explanatory diagram of the operation, FIG. 5 is a partial perspective view of the sewing machine, and FIG. 6 is a second view of the inner hook of a conventional rotary hook. FIG. 10...Sewing machine, 14...Upper thread, 44...Rotary hook, 46...Outer hook, 50...Inner hook, 54...Lower thread, 56...Bobbin case, 66...Notch, 6
8... Thread entanglement prevention member.

Claims (1)

[Scope of utility model registration request] an outer hook that rotates in response to a driving force; an inner hook that is housed in the outer hook with a bobbin case built-in;
In the rotary hook of the sewing machine, the inner hook is provided with a cantilever-like entanglement prevention member that covers at intervals an entrance of a notch through which the bobbin thread wound around the bobbin case is pulled out from the inner hook. A rotary pot of a sewing machine that is characterized by: