JPH0517032Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention has the configuration described in the generic concept of claim 1 of the utility model registration, that is, a movable clamp surface that is crimped to a fixedly provided clamp surface via a spring. , with blades with cutting edges arranged transversely to these clamping surfaces, and a casing attached to the device, the fixedly provided clamping surfaces being on the inside of the front wall of the casing. a movable clamping surface is provided in the casing against a pressing member that is slidable over the bolt and presses against the clamping surface by means of a spring; A bolt inserted extending at an acute angle to the clamping surface is fixed to the rear wall of the casing opposite the fixed clamping surface, and this is formed through an opening in the front of the upper sewing part of the sewing machine. The present invention relates to a sewing thread tightening and cutting device for a sewing machine, which is configured to be provided in a recessed portion of the sewing machine.

For example, if the thread becomes tangled and sewing is interrupted,
At the end of sewing, the two threads threaded through the sewing machine must be separated. In order to separate both threads and firmly hold the end of the cut thread leading to the sewing machine, a device for fixing the thread after cutting is disclosed in a patent published by the Federal Republic of Germany.
It is publicly known from the publication No. 2814965. The device consists of two dish-shaped clamp plates, one of which is resiliently supported and the other pressed.

This known device is fixed to the sewing machine as an external, separate machine part. A blade is inserted between both clamp plates on the side of the clamp surface. The two threads coming out of the object to be sewn are placed between the clamp plates and then torn into two by the blade. The two threads passing through the needle or the looper of the sewing machine are held at their ends by a clamp plate, from which they are pulled out when the next sewing operation begins.

The object of the invention is therefore to provide a thread tightening and cutting device for a suture thread of the above-mentioned type, such that after the thread has been cut off, the thread has a clean cross-section of the fiber ends in the cross-sectional plane. It is also an object of the present invention to provide a device that can be integrated into a sewing machine casing.

The suture thread tightening and cutting device according to the present invention solves this problem by fixing the bolt to the rear wall of the casing facing the fixed clamp surface and , the thread tightening and cutting device is arranged in a recess formed through an opening in the front face of the upper sewing machine part of the sewing machine.

The cutting edge of the blade, set at an acute angle to the clamping surface on the one hand, and the large clamping surface, which does not penetrate the mandrel, on the other hand, make it possible to separate the thread in a "pull" section. . This has the advantage that the cross-section can be created with very little tension and that twisting, which causes fraying, can therefore be easily avoided. The sides of the casing that constitute the fixed clamping surfaces are arranged in such a way that the user of the sewing machine is forced to pull the thread down along the casing of the sewing machine until it reaches the clamping and cutting area of the device. Conveniently, the thread tightening and cutting device passes through a dovetail guide inside the sewing machine casing. The end of the casing of the thread tightening and cutting device, configured in the shape of a nose, fixes it in the guide of the sewing machine casing.

Other advantageous aspects of the present invention are described in claims 2 and below.

That is, one configuration is such that the front wall of the device protrudes from the front face of the sewing machine such that the thread insertion gap between the front wall and the front face is formed through the clamping surfaces. be. The other configuration is such that a notch or gap exists between the other side wall and the front wall of the casing. It is also preferred that the edge of the front wall facing the side wall is bent and protrudes beyond the fixed clamping surface. Furthermore,
The blade may be fixed to the side wall and/or the bottom, or the bottom and/or side wall may be provided with a guide part with a hook so that the device engages with the casing of the sewing machine, or it may be dovetail-shaped or dovetailed. It is also preferable that the guide portion inserted into the joint-shaped guide is formed in the casing of the sewing machine, or that the bolt for the pressing member is fixed to the guide portion or the side wall.

The invention will be explained in detail with reference to the illustrated embodiments.

In the sewing machine 1 schematically shown in FIG.
At the front of the upper sewing machine part 5, on the front surface or below the rear edge 7 of the front face 3, a small thread tightening and cutting device 9, hereinafter referred to only as device 9, is fitted into the housing 11 of the sewing machine 1. Therefore, the device 9 is located above the sewing material carrying surface 16 and behind the needle bar 13 provided with the needles 15.

In FIG. 2, which is a rear view of the upper sewing machine part 5, the position of the front wall 17 of the casing 19 of the device 9 can be seen. The front wall 17 projects from the front face 3 of the sewing machine 1 and forms a narrow gap 21 between the front face 3 and the front wall 17.

The casing of the device 9 basically consists of a side wall 23, a bottom 25, a front wall 17 and a rear wall 27, the rear wall 27 having a nose-shaped hook 31 and a rectangular plate-shaped guide continuation of the side wall 23. Part 29 is attached.

Bolts 33 are attached to the rear wall 27, e.g.
It is pasted into the hole or fixed by screwing. A low hole 37 is provided at the free end of the bolt 33.
A pressure element 35 is mounted which has a sleeve-shaped neck 38.
A spring 39 is wound around the bolt 33, and the front wall 1
A pressing member 35 is pressed against the inner surface of 7. The inner surface constitutes a fixed clamping surface 41, and the front surface of the pressing member 35 constitutes a movable clamping surface 43 (FIG. 5).

The front wall 17 and the side wall 23 are not directly connected,
They are joined to each other via the bottom portion 25, with a slit-like gap 45 formed therebetween. Above that, the front wall 17
is slightly distorted at the position facing the gap 45, and the cutting edge 47 of the blade 49 fixed to the front wall 17 can be seen from the side (third
(Fig.), is covered by a partially curved edge 50. The cutting edge 47 is placed at an acute angle on the front wall 1.
It extends downward to the right and away from the upper edge of 7 (from the upper left). The blade 49 is the pressing member 35
and the side wall 23, essentially parallel to the axis of the bolt 33. Blade 49 is secured to side wall 23 by a plastic drift pin 52.

Casing 11 of sewing machine 1 for guide part 29
A dovetail guide 51 is mounted inside the guide 51 into which the device 9 is inserted through an opening 53 in the front face 3 and held tightly therein by the hook 31. has been done.

The gap 45 essentially coincides with the gap 21 formed by the front face 3 of the sewing machine and the front wall 17 of the device 9 when the device 9 is inserted. On the other hand, the opening 53
is not only the front side 3 but also the casing 11 of the sewing machine 1.
, so that when the device 9 is inserted, the side wall 23 effectively covers the rear opening portion of the opening 53 (FIG. 6). Needless to say, the device 9 can be fixed by screw connection or as shown in FIG.
Casing 11 passing through the hole of guide portion 29
This is done by means of plastic bolts 55 attached to the.

The workpiece 57 is withdrawn from the area of the needle 15 in order to bisect both the upper thread 59 and the lower thread 61 which extend from the already sewn workpiece 57 to the sewing machine 1 . Accordingly, both threads 59, 61 which extend between the sewing machine 1 and the workpiece 57 extend along the front surface 3, possibly even around the edge 7 to touch the sewing machine 1 and downward. , where both threads slide behind the front wall 17 of the device 9 and against the clamping surface 41
It moves by passing between and 43. Further pulling on the workpiece 57 causes the threads 59, 61 to slide downwardly along the cutting edge 47 in a "pull" cut and be severed with a sharp cut. needle 15
Alternatively, both threads 59, 61 leading to the free arm of the sewing machine 1 are held close to the cut end between the clamping surfaces 41 and 43, so that they can be easily pulled out for the next operation. There is.

Naturally, the device 9 can also be inserted at other locations on the sewing machine 1. One possible location is the rear upper corner of the free arm. The device 9 is economical to manufacture and can be easily replaced if necessary.

[Brief explanation of the drawing]

Fig. 1 is a schematic perspective view of the sewing machine, Fig. 2 is a partial rear view of the sewing machine, Fig. 3 is an elevational view of the thread tightening and cutting device, and Fig. 4 is a sewing machine with a built-in thread tightening and cutting device. FIG. 5 is a plan view of the thread tightening and cutting device (the outline of the sewing machine is shown in chain lines), and FIG. 6 is a thread tightening and cutting device according to a different embodiment. 1... Sewing machine, 3... Front, 5... Upper sewing machine part, 9... Thread tightening and cutting device, 19... Casing, 27... Rear wall, 33... Bolt, 41
... Clamp surface, 43 ... Opening.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A thread tightening and cutting device for sewing thread attached to a sewing machine, including a movable clamp surface that is crimped to a fixed clamp surface via a spring, and these clamp surfaces. a blade with a cutting edge disposed transversely to the device, and a casing attached to the device, with a fixedly provided clamping surface being formed by the inside of the front wall of the casing; A movable clamping surface is provided in the casing in contact with a pressing member that presses the clamping surface with a spring so as to be able to slide on the bolt, and furthermore, the cutting edge of the blade is provided against both clamping surfaces. In a suture thread tightening and cutting device inserted at an acute angle, the bolt 33 is fixed to the rear wall 27 of the casing 19 opposite the fixed clamping surface 41, and the device 9 is installed on a sewing machine. 1. A thread tightening and cutting device for a sewing thread, characterized in that it is provided in a recess formed through an opening 53 in the front face 3 of the upper sewing machine part 5 of 1. (2) The front wall 17 of the device 9 is arranged so that the gap 21 for insertion of the threads 59, 61 between the front wall 17 and the front surface 3 is formed through the clamping surfaces 41, 43.
The device according to claim (1) of the utility model registration, characterized in that it protrudes from the front surface 3 of the sewing machine 1. (3) Rear side wall 23 and front wall 17 of casing 19
Utility model registration claim No. 4 characterized in that there is a notch or gap 45 between
The device described in paragraph (2). (4) The device according to claim (3) of the utility model registration claim, characterized in that the edge 50 of the front wall 17 facing the side wall 23 is bent and protrudes beyond the fixed clamping surface 41. . (5) The blade 49 is connected to the side wall 23 and/or the bottom 25
The device according to claim (4) of the utility model registration claim, characterized in that the device is fixed to: (6) Utility model registration claim No. 1 characterized in that a guide portion 29 with a hook portion 31 is provided on the bottom portion 25 and/or side wall 23 so that the device 9 is engaged with the casing 11 of the sewing machine 1. (1)
The device according to any one of (5) to (5). (7) The utility model according to claim (6), characterized in that the guide portion 29 inserted into the dovetail-shaped or dovetail-shaped guide 51 is formed in the casing 11 of the sewing machine 1. Device. (8) The device according to any one of claims (1) to (7) for utility model registration, characterized in that the bolt for the pressing member 35 is fixed to the guide portion 29 or the side wall 23. .