JPH0740383Y2 - Thread tension device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a thread tension device, and more particularly to a thread tension device that holds a thread by two thread tension discs.

[Prior Art] In a conventional thread tension device, two thread tension discs 100 are supported by a support shaft 102 as shown in FIGS. 7A, 7B and 7C, and each thread tension disc 100 has a predetermined width. Protrusions 101 extending in the circumferential direction are provided. Then, the thread T ′ of the protrusion 101
The yarn T'is held by two portions 101a and 101b engaging with the thread T '.

However, in this thread tension device, as the thread T ′ is consumed, a force is applied to T ′ in the direction of arrow A, and the thread T ′ moves to the outside of the protrusion 101 (hereinafter referred to as thread ejection) thread T ′. There is a problem that the holding pressure cannot be applied to.

Further, in the conventional thread tension device shown in FIGS. 8A, 8B and 8C, it is proposed that the thread tension tray 103 is provided with the notch 105 at the first engaging portion with T '. There is. According to this device, the yarn T ′ is prevented from moving to the outside of the protrusion 101 by the side wall 105a of the cutout 105, so that the yarn T ′ can be prevented from being ejected.

However, in this device, there is a problem in that only one portion 104a of the protrusion 104 applies a clamping pressure to the yarn T ', and it becomes impossible to apply a sufficient clamping pressure to the yarn T'.

Therefore, as shown in FIG. 9, a notch 108 smaller than a predetermined width of the protrusion 107 of the thread tension disc 106 is provided to prevent the thread T ′ from being ejected, and the protrusion 107 has two portions 107a and 107b. It is conceivable that the yarn T'is held between the two.

[Problems to be Solved by the Invention] However, like the thread tension device shown in FIG. 9, on the side of the support shaft 12 where the bottom side 108a that defines the notch 108 and the thread T'extending in the notch 108 intersect. When the angle θ'is formed to be larger than 90 degrees, the yarn T'is moved along the bottom side 108a as the yarn T'is consumed, and the yarn T'is ejected. In particular, this problem is likely to occur when a hump-shaped portion of the yarn T'formed between the yarns (hereinafter referred to as a twisted portion of the yarn) passes between the thread tension discs 106.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a thread tension device capable of preventing the thread from coming out and providing a stable clamping pressure.

[Means for Solving the Problem] In order to achieve this object, a thread tension device of the present invention is provided on two thread tension discs supported on a support shaft, and has a predetermined width for engaging with a thread. And a circular protrusion extending in the circumferential direction, and a notch formed in a portion of the protrusion that first engages with the thread and formed to be smaller than a predetermined width, and defining a notch. And the angle on the side of the support shaft where the yarn guiding path extending into the cutout portion intersects is 90 degrees or less.

[Operation] In the thread tension device of the present invention having the above structure, when the twisted portion of the thread passes between the two thread tension trays, the thread tension device moves to the outside of the protrusion along the bottom defining the notch. To prevent

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings.

1 and 2, the sewing machine frame 10 has a support shaft 12
Is fixed, and two disk-shaped thread tension discs 14 and 16 are fitted to the support shaft 12. A threaded portion is formed at the tip of the support shaft 12, and an adjusting knob 18 is screwed into the threaded portion. A winding spring 20 is provided between the adjusting knob 18 and the thread tension disc 16, and the thread tension disc 16 is inserted into the thread tension disc 14.
It is configured to press. Further, the pin 22 for preventing the two thread tension discs 14 and 16 from rotating is provided with the sewing machine frame 10.
It is provided in. A thread hooking body 24 for guiding the thread T drawn out from a thread winding (not shown) toward the thread tension trays 14 and 16 is provided in the sewing machine frame 10 and the thread tension tray 1
A thread guide body 28 for guiding the thread T passing between 4 and 16 to the balance 26 is provided in the sewing machine frame 10.

As shown in FIGS. 2 and 3, the thread tension disc 14 is provided with a protrusion 30 having a predetermined width and extending along the circumferential direction thereof. The protrusion 30 is provided with a notch 32 at a portion that first intersects with the thread T guided from the thread hooking body 24. In addition, the bottom wall 32a that defines the cutout 32 is the thread tension disc 1
Between 4 and 16, the angle θ on the support shaft side with the thread T (thread guide path) passing through the notch 32 is configured to be approximately 80 degrees. The thread tension disc 16 is also formed with a projection 34 having a predetermined width and extending along the circumferential direction thereof.

The operation of the thread tension device configured as described above will be described.

The thread T passing between the two thread tension discs 14 and 16 is given a holding pressure at the two holding pressure applying portions B and C by the respective protrusions 30 and 34 after passing through the notch 32. And the thread T,
In particular, the twisted portion of the thread T extends from the notch 32 to the holding pressure applying portion B.
When moving to, the yarn T moves along the bottom wall 32a in the direction of arrow D, that is, toward the inside of the protrusions 30 and 34 so that the holding pressure by the applying portion B is not applied.

The present invention is not limited to the above-described embodiment, and various modifications can be added.

For example, in the present embodiment, the angle θ on the support shaft 12 side between the bottom wall 32a and the thread T is configured to be approximately 80 degrees, but the angle at which the thread T does not move to the outside of the protrusion. You may That is, as shown in FIG. 4, the angle θ on the support shaft 12 side between the bottom wall 40a of the notch 40 provided in the protrusion 38 and the thread T may be not more than 90 degrees with the upper limit being 90 degrees.

Alternatively, a semicircular cutout 42 may be provided as shown in FIG. In this case, the angle θ on the support shaft 12 side between the tangent line Q of the circumferential wall 42a of the cutout portion 42 and the yarn T (yarn guiding path) at the portion where the yarn T and the yarn T intersect is 90 degrees or less. The cutout 42 is formed.

Again, as shown in FIG. 6, the notch 44 may be formed so as to be slanted with respect to the protrusion 46. Notch in this case
It is not the bottom wall that defines 44 but the bottom line 44a, and although not shown, the angle between the bottom line 44a and the thread T (thread guide path) on the support shaft side is 90 degrees or less. Needless to say.

[Effects of the Invention] As described in detail above, according to the thread tension device of the present invention, the thread can be reliably held between the two portions of the protrusion of the thread tension tray, and the thread can be prevented from being ejected. A stable and stable thread tension can be obtained.

[Brief description of drawings]

1 to 3 show an embodiment embodying the present invention. FIG. 1 is an external perspective view showing a thread tension device of this embodiment, and FIG. 2 is a partial enlargement of the thread tension device. Sectional drawing, FIG. 3 is an explanatory view for explaining the relationship between the thread tension tray and the thread, FIG. 4 is an explanatory view for explaining the relationship between the thread tension tray and the thread of the first modified example of the present invention, and FIG. FIG. 7 is an explanatory view for explaining the relationship between the thread tension disc and the thread of the second modification of the present invention, FIG. 6 is a sectional view showing the thread tension disc of the third modification of the present invention, and FIG. Is a perspective view of the first conventional tension disc, FIG. 7b is a sectional view of the above-mentioned tension disc,
7c is an explanatory view for explaining the relationship between the thread tension tray and the thread, FIG. 8a is a perspective view of a second conventional thread tension tray, and FIG. 8b is a sectional view of the thread tension tray. FIG. 8c is an explanatory view for explaining the relationship between the thread tension tray and the thread, and FIG. 9 is an explanatory view for explaining the relationship between the third conventional thread tension tray and the thread. In the figure, 10 is a machine frame, 12 is a support shaft, 14 and 16 are thread tension discs, 30, 34, 38 and 44 are protrusions, 32, 40, 42 and 44 are notches, 32a,
40a is a bottom wall, 42a is a circumferential wall, and 44a is a bottom line.

Claims (1)

[Scope of utility model registration request] A thread tension tray (14, 16) is provided on a support shaft (12) attached to a sewing machine frame (10) for holding a thread (T) between them. In the thread tension device, circular protrusions (in the circumferential direction) provided on the two thread tension discs (14, 16) and having a predetermined width for engaging with the thread (T) ( 30,34,38,46) and the notch (32,40) formed at the first engaging portion of the protrusion (30,34,38,46) with the thread and formed smaller than the predetermined width. , 42, 44) and defining the notch (32, 40, 42, 44) at the bottom (32a, 40a, 4)
2a, 44a) and the thread guide path extending into the cutout portion (32, 40, 42, 44) has an angle of 90 degrees or less on the side where the thread tension device intersects.