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Patent Searching and Data


Title:
THREAD CUTTING SYSTEM
Document Type and Number:
WIPO Patent Application WO/2021/137836
Kind Code:
A1
Abstract:
In order to sew thread to a work piece on which sewing process will be applied, a thread cutting system that has a sewing needle, sewing area in the form of a planar surface, vacuum element that provides vacuum, is suitable for use in sewing machines suitable for chain stitch sewing, comprises the following; at least one body (1) that provides the connection of the system to the sewing machine and the transport of the system elements; at least one vacuum channel (2) that has at least one vacuum opening (2a) that allows to receive excess thread therein, helps to remove the cut thread from the sewing area by vacuum effect. Moreover, it comprises first cutting blade (3a) and second cutting blade (3b) so as to provide cutting the excess thread; shaft slot (4) suitable for shaft positioning therein; motion shaft (5) suitable for performing a first bidirectional movement along the extension direction and a second movement in a circular direction around the extension direction; cutting element (6) comprising the third cutting blade (6a) for cutting the excess thread, prevents the excess thread from being wound or jammed by providing the excess thread to be cut and to be pushed towards the vacuum channel (2); first movement element (7) that provides the motion shaft (5) to perform the first movement; second movement element (8) that provides the motion shaft (5) to perform the second movement.

Inventors:
KESKİN HÜSEYIN (TR)
Application Number:
PCT/TR2020/051445
Publication Date:
July 08, 2021
Filing Date:
December 30, 2020
Export Citation:
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Assignee:
ASIL GRUP MAKINA SANAYI VE DIS TICARET LTD SIRKETI (TR)
International Classes:
D05B65/06; D05B65/00; D05B69/00; D05B81/00
Foreign References:
US4138957A1979-02-13
GB1369261A1974-10-02
CN207176252U2018-04-03
CN209703017U2019-11-29
TW201317416A2013-05-01
DE102007045597A12008-04-03
CN101353850A2009-01-28
Attorney, Agent or Firm:
DESTEK PATENT, INC. (TR)
Download PDF:
Claims:
CLAIMS

1. A thread cutting system has at least one sewing needle that is movable in a way to move closer and away from the workpiece so as to perform sewing process on a work piece, at least one sewing area in the form of a planar surface that provides the work piece to be positioned horizontally on the floor so as to sew the work piece properly, at least one vacuum element that provides vacuum to cut the treads from the sewing area, is suitable for use in the sewing machines suitable for chain stitch sewing and provides the excess thread not sewn on the workpiece to be cut comprises the following; characterized in that; it comprises the following; at least one body (1) that provides the connection of said system to the sewing machine and carrying the elements of the system; at least one vacuum channel (2) that comprises at least one vacuum opening (2a) extending from the edge close to said sewing needle to the surface of the sewing area distal to the base and removing the excess thread, that is located on the side of the sewing area close to the base in connection with the vacuum element, extends in the direction of progress of the work piece passed between the sewing needle and the sewing area so as to carry out the sewing process and helps to remove the cut thread from the sewing area by vacuum effect; at least one first cutting blade (3a) which is located fixedly on the edge of said vacuum opening (2a) close to said sewing needle and enables the excess thread to be cut; at least one second cutting blade (3b) which is located fixedly on the edge of said vacuum opening (2a) distal to said sewing needle and enables the excess thread to be cut; at least one shaft slot (4) which extends parallel to said vacuum channel (2) in connection with said body (1) and has a structure suitable for locating a shaft in the form of a rod; at least one motion shaft (5) in said motion slot (4), is located with one end over said vacuum opening (2a) and extends parallel to said vacuum channel (2), is suitable for performing a first bidirectional movement along the extension direction and a second movement in a circular direction around the extension direction; at least one cutting element (6) that comprises at least and third cutting blade (6a) that enables cutting the excess yarn by approaching the first cutting blade (3a) or the second cutting blade (3b) on the side close to the vacuum opening (2a), is fixedly connected to the end of the motion shaft (5) close to the vacuum opening (2a), extends towards the vacuum opening (2) so as to be perpendicular to the extending axis of the motion shaft (5), provides cutting said excess thread and at the same time prevents the excess thread from entangling or jamming by pushing the cut excess thread towards said vacuum channel (2), at least one first movement element (7) which is connected to the end of the motion shaft (5) distal to the vacuum opening (2a) and provides the movement shaft (5) to perform the first movement so as to bring the cutting element (6) closer to the first cutting blade (3a) or the second cutting blade (3b); at least one second movement element (8) which is connected to the end of said motion shaft (5) distal to the vacuum opening (2a) and provides said motion shaft (5) to perform said second movement so as to bring said cutting element (6) towards said first cutting blade (3a) with said vacuum opening (2a) or to said second cutting blade (3b) with said vacuum opening (2a).

2. The thread cutting system according to claim 1 , characterized in that; said work piece is fabric.

3. The thread cutting system according to claim 1 , characterized in that; said vacuum opening (2a) has a square form.

4. The thread cutting system according to claim 1 , characterized in that; said first cutting blade (3a), said second cutting blade (3b) and/or said third cutting blade (6a) is in the form of a knife or razor blade.

5. The thread cutting system according to claim 1 , characterized in that; said motion shaft (5) is in the form of a cylindrical rod.

6. The thread cutting system according to claim 1 , characterized in that; said first movement element (7) is a piston with pneumatic feature.

7. The thread cutting system according to claim 1 , characterized in that; said second movement element (8) comprises a piston with pneumatic property, at least one rack gear connected with said piston and at least one gearwheel that receives rack gear. 8. The thread cutting system according to claim 1 , characterized in that; said cutting element (6) comprises at least two third cutting blades (6a), one of which is located on the edge close to said first cutting blade (3a), enables said excess thread to be cut by approaching said first cutting blade (3a) and another one of which is located on the edge close to said second cutting blade (3b), enables cutting said excess thread by bringing the same closer to said second cutting blade (3b).

9. The thread cutting system according to claim 1 , characterized in that; it comprises at least one cutting element (6) that comprises at least two third cutting blades (6a) which is formed by sharpening a first edge positioned close to and parallel to said first cutting blade (3a) on the edge close to said vacuum opening (2a) and a second edge positioned close and parallel to said second cutting blade (3b), enables cutting said excess thread by approaching said first edge to said first cutting blade (3a) or said second edge to said second cutting blade (3b) and at least one interface between said first edge and said second edge, extends parallel to said vacuum channel (2), prevents the excess thread from twisting or jamming by pushing the cut excess thread towards said vacuum channel (2).

10. The thread cutting system according to claim 1 , characterized in that; it comprises at least one sensor element which is preferably an optical sensor that is located close to said vacuum opening, enables the detection of the approach of an inlet edge located on the progress direction and an outlet edge located on the opposite side to the progress direction of the workpiece advanced during the sewing process, to said vacuum opening (2a).

11. The thread cutting system according to claim 1 , characterized in that; it comprises, in case said inlet edge approaches said vacuum opening (2a) in the direction of the information received from said sensor element that is in connection with said sensor element, in case said cutting element (6) approaches to said first cutting blade (3a) and said outlet edge approaches said vacuum opening (2a), a control element that provides control of the operation of said first movement element (7) and said second movement element (8) so as to bring said cutting element (6) closer to said cutting blade (3b).

Description:
THREAD CUTTING SYSTEM

Technical Field

The invention relates to a thread cutting system that provides cutting excessive sewing thread on the sewing machines.

Particularly, the invention relates to a thread cutting system used in chain stich sewing machines during sewing that provides cutting excess sewing thread on the fabric edge left without being stitched.

State of the Art

In the sewing machines, the sewing thread on a bobbin is sewn to a workpiece that is generally a fabric in a serial manner by means of a needle that carries out the sewing process. Particularly in chain stich sewing machines, the sewing process is performed with the sewing needle located at the inlet of the sewing line by means of pricking and coming of the workpiece surface serially as soon as the user inserts the workpiece to be sewn into a sewing line where the sewing process is carried out and in the meanwhile, the thread is provided to be sewn on the workpiece in the form of a ring chain along a linear line by moving the workpiece along the sewing line. The sewing thread must be cut at a point close to the inlet edge of the work piece entering the sewing line first and the output edge of the same that exits last from the sewing line so as to complete the chain stitching process. A thread cutting system or mechanism is used for this process in said sewing machines so as to cut the excess thread which is the continuation of the chain stitch and is not sewn to the surface of the workpiece at a point that is close to said inlet and outlet edges of the workpiece. In this mechanism, the excess thread is cut with the approach of a pair of blades to each other that are located behind the sewing thread on the sewing line and the remaing cut thread is removed from the sewing line by means of a vacuum channel.

Current thread cutting systems can have two separate mechanisms called horizontal or guillotine. In the horizontal type thread cutting systems, among these, there is a vacuum opening that allows the excess thread to enter into the vacuum channel that is located after the sewing needle on the sewing line, enables the cut thread to be removed from the sewing line and the pair of blades that provides cutting the excess thread are located on the edge of the vacuum opening that is at a distance to the sewing needle. Thus, first the excess thread is entered into the vacuum opening and then is cut by a pair of blades in the vacuum channel. However, in the horizontal type thread cutting systems, the remaining uncut thread length connected to the inlet edge of the workpiece due to positioning of the blade pair after the vacuum opening is excessive or cannot be cut properly. The workpiece is required to be slid forward and backward on the sewing line by the user so as to cut the excess thread at the outlet edge of the workpiece and this situation leads to loss of both efficiency and time. Since the excess thread first enters the vacuum opening, adverse conditions may occur such as cutting the overcasting stich applied so as to clean the eaves of the workpiece edge or fabric edge by pair of blades. Moreover, the pair of blades in the system must operate continuously depending on the operation mode of this type of thread cutting systems and thus this causes extra energy loss, reduced lifetime based on rapid wear and increased occurrence of technical failures.

In another cutting system called guillotine type thread cutting systems, said pair of blades are located on the sewing line, such that they are positioned at a distance from the sewing needle, on the edge of the vacuum opening closer to the sewing needle. Thus, first of all the excess thread is cut by means of the pair of blades and then the cut thread is removed by the vacuum channel as soon as it enters into the vacuum opening. Therefore, the workpiece does not need to be slid forward and backward by the user and the fabric edge or overcasting stitch is prevented from being cut off accidentally. However, the system is required to be operated for a while after the cutting process so as to pull the cut excess thread into the vacuum channel in this type of thread cutting systems and this situation leads to extra energy and time loss in conditions where it is required to apply serial and excessive sewing process. Moreover, as a result of the excess thread twisting or dispersing after the cutting process of the pair of blades, negative situations may occur such as the cut thread’s not entering the vacuum channel properly or sticking around the other parts included in the cutting line etc. due to excess thread’s not entering the vacuum opening and the thread’s having less tension. While this situation leads to disruption of the sewing quality and sewing errors, it also causes technical problems such as breaking of the thread and decalibration of the machine. The process time extends due to the requirement of cleaning the sewing line between each sewing process by the operator.

In the patent document numbered US4138957A, a vacuum thread cutting system developed for use in the automatic sewing machines is disclosed. Said system comprises the following; the sewing line where the cutting process is carried out, the movement elements that enable the progress of the workpiece to be sewn, the sewing needle performing the sewing process, the vacuum channel and vacuum source that allows the cut thread to be pulled, the vacuum channel opening that allows the thread to enter the vacuum channel and the cutting blades located at the edge of the vacuum channel. The structure of this system is suitable for the horizontal type thread cutting system, the thread cutting blades are located on the side of the vacuum channel mouth distant from the sewing needles and thus the loosening/slumping of the thread that occur in guillotine type thread cutting systems is prevented. Said systems include channel grooves to allow the thread to enter the vacuum channel more properly. However, in said document, no solution is proposed so as to prevent negative situations such as the length of uncut thread remained due to the inlet edge of the workpiece, or not being able to cut properly, the requirement of sliding the workpiece back and forth on the sewing line, cutting the workpiece edge or overcasting stitch etc. due to the positioning of the cutting blade after said mouth.

As a result, in the chain stitch machines, a thread cutting system that provides to cut the excess thread which is the continuation of the thread sewn to the workpiece and is not sewn on the workpiece surface, properly from a point close to the workpiece, to remove the cut thread efficiently by preventing the cut thread from getting stuck in a piece of the sewing machine, to eliminate extra movement of the user on the workpiece for the cutting process and to prevent accidental cutting of the workpiece edge or surging stitch, is required to be developed.

Aim of the Invention

The present invention is related to a thread cutting system which fulfils the above mentioned requirements, eliminates all disadvantages and brings some additional advantages.

The main aim of the inventive thread cutting system is to provide a thread cutting system that provides cutting the excess thread that is not sewn on the workpiece in chain stitch machines properly at a point close to the workpiece and provides the cut thread to be removed effectively from the area where sewing is carried out.

Another aim of the invention is to provide a thread cutting system that prevents the cut thread during and after the cutting process from getting caught or jammed in a part of the sewing machine.

Another aim of the invention is to provide a thread cutting system that operates in a practical and fast manner without requiring an extra movement or process of the user during the cutting process.

Another aim of the invention is to provide an effective thread cutting system that provides long life operation by saving energy and reducing wear duration of the parts by preventing the system from excessive operation before and after the cutting process. In order to achieve the above mentioned aims in general, a thread cutting system that has a sewing needle suitable for sewing a thread to a workpiece on which sewing process will be applied, at least one sewing area in the form of a planar surface, at least one vacuum element that provides vacuum, is suitable for use in sewing machines suitable for chain stitch sewing, comprises the following; at least one body that provides the connection of the system to the sewing machine and the transport of the system elements; at least one vacuum channel that has at least one vacuum opening that allows to receive excess thread therein, helps to remove the cut thread from the sewing area by vacuum effect. Moreover, it comprises at least one first cutting blade and at least one second cutting blade so as to provide cutting the excess thread; at least one shaft slot suitable for shaft positioning therein; at least one motion shaft suitable for performing a first bidirectional movement along the extension direction and a second movement in a circular direction around the extension direction; at least one cutting element comprising at least a third cutting blade for cutting the excess thread; first movement element that provides the motion shaft to perform the first movement; at least one second movement element that provides the motion shaft to perform the second movement.

The structural and characteristic features of the present invention will be understood clearly by the following drawings and the detailed description made with reference to these drawings and therefore the evaluation shall be made by taking these figures and the detailed description into consideration.

Figures Clarifying the Invention

In order to understand the advantages of the present invention with its structure and additional elements, it shall be evaluated with the following defined figures.

Figure - 1 : Is a front perspective view of the inventive thread cutting system.

Figure - 2: Is a side view of the inventive thread cutting system.

Figure - 3: Is a plan view of the inventive thread cutting system.

Part References

1 . Body

2. Vacuum channel

2a. Vacuum opening

3a. First cutting blade

3b. Second cutting blade 4. Shaft slot

5. Motion shaft

6. Cutting element

6a. Third cutting blade

7. First movement element

8. Second movement element

Detailed Description of the Invention

In this detailed description, the preferred embodiments of the inventive thread cutting system is described only for clarifying the subject matter in a manner such that no limiting effect is created.

A thread cutting system whose representative view is given in Figure 1 , is developed with the present invention, is suitable for use in sewing machines suitable for chain stitch sewing and enables the cutting of excess thread that is not sewn to the workpiece, has at least one sewing needle that is movable in a way to move closer and away from the workpiece so as to perform sewing process on a work piece preferably a fabric, at least one sewing area in the form of a planar surface that provides the work piece to be positioned horizontally on the background so as to sew the work piece properly, at least one vacuum element that provides vacuum to cut the threads from the sewing area comprises the following; at least one body (1 ); at least one vacuum channel (2) that comprises at least one vacuum opening (2a) extending from its edge close to the sewing needle to the surface of the sewing area at a distant to the base and removing the excess thread, preferably in the form of a square, that is located on the side of the sewing area close to the base in connection with the vacuum element, extends in the direction of progress of the work piece passed between the sewing needle and the sewing area so as to carry out the sewing process and helps to remove the cut thread from the sewing area by vacuum effect. Moreover it comprises; at least one first cutting blade (3a) that is located on the side of the vacuum opening (2a) close to the sewing needle in a fixed manner and enables to cut the excess thread, is preferably in the form of a blade or a razor blade; at least one second cutting blade (3b) that is located on the side of the vacuum opening (2a) distal to the sewing needle in a fixed manner and enables to cut the excess thread, is preferably in the form of a blade or a razor blade; at least one shaft slot (4) that extends parallel to the vacuum channel (2) in connection with the body (1), has a structure suitable for locating a rod-formed shaft therein; at least one motion shaft (5) that is located in the shaft slot (4) with one end on the vacuum opening (2a) and extends parallel to the vacuum channel (2), is suitable for performing a first bidirectional movement along the extension direction and a second movement in a circular direction around the extension direction, is preferably in the form of a cylindrical rod; at least one cutting element (6) that comprises at least a third cutting blade (6a) that enables cutting the excess thread by approaching the first cutting blade (3a) or the second cutting blade (3b) on the side close to the vacuum opening (2a), is fixedly connected to the end of the motion shaft (5) close to the vacuum opening (2a), extends towards the vacuum opening (2) so as to be perpendicular to the extending axis of the motion shaft (5), provides cutting said excess thread and at the same time prevents the excess thread from entangling or jamming by pushing the cut excess thread towards said vacuum channel (2). Said thread cutting system also comprises at least one first movement element (7) which is connected to the end of the motion shaft (5) distal to the vacuum opening (2a) and provides the movement shaft (5) to perform the first movement so as to bring the cutting element (6) closer to the first cutting blade (3a) or the second cutting blade (3b), has preferably a piston with pneumatic feature; at least one second movement element (8) which preferably comprises a piston with pneumatic feature in connection with the end of the motion shaft (5) distal to the vacuum opening (2a), at least one rack in connection with said piston and at least one gear wheel receiving the rack gear, enables the motion shaft (5) to perform the second movement so as to bring the cutting element (6) towards the first cutting blade (3a) with the vacuum opening (2a) or towards the second cutting blade (3b) with the vacuum opening (2a).

In an exemplary embodiment of the thread cutting system developed with the present invention, it is passed between the sewing needle of the workpiece to be sewn and the sewing area and thus chain stitching is made on the surface of the workpiece. In the meantime, the motion shaft (5) and the cutting element (6) connected to the motion shaft (5) are provided to perform the first movement and to be brought to the level of the first cutting blade (3a) by means of the first movement element (7). When the excess thread that is connected to the inlet edge of the workpiece which is advanced linearly, located on the direction of progress and is not sewn on the surface of the workpiece, approaches to the vacuum opening (2a), the motion shaft (5) and the cutting element (6) are rotated by performing the second movement by means of the second movement element (8) and are brought closer to the first cutting blade (3a). Therefore, it is provided to cut the excess thread connected to the inlet edge of the workpiece and to transfer the cut thread directly to the vacuum channel (2) by being vacuumed through the vacuum opening (2a). Then, it is provided to rotate the cutting element (6) by means of the second movement element (8) such that it is distal from the vacuum opening (2a) and to bring the motion shaft (5) and cutting element (6) to the level of the second cutting blade (3b) with the first movement by means of the first movement element (7). When the excess thread that is connected to the outlet edge of the workpiece which is advanced linearly, located on the opposite direction of progress and is not sewn on the surface of the workpiece, approaches to the vacuum opening (2a), it is provided to bring the motion shaft (5) and the cutting element (6) to the second cutting blade (3b) by rotation by means of the second movement element (8). Therefore, it is provided to cut the excess thread connected to the outlet edge of the workpiece at a point closer to the workpiece and to transfer the cut thread directly to the vacuum channel (2) by being vacuumed through the vacuum opening (2a). Then the system becomes ready for a new sewing and cutting process by providing the rotation of the cutting element (6) by means of the second movement element (8) such that it is distal from the vacuum opening (2a). Therefore, it is provided to cut the excess thread connected to the inlet edge of the workpiece similar to the guillotine type thread cutting systems and to cut the excess thread connected to the outlet edge of the workpiece similar to the horizontal type thread cutting systems.

The thread cutting system disclosed in a preferred embodiment of the invention comprises the following; at least one cutting element (6) that comprises at least two third cutting blades (6a), one of which is located on the edge close to said first cutting blade (3a), enables said excess thread to be cut by approaching said first cutting blade (3a) and another one of which is located on the edge close to said second cutting blade (3b), enables cutting said excess thread by bringing the same closer to said second cutting blade (3b).

The thread cutting system disclosed in another preferred embodiment of the invention comprises the following; at least one sensor element which is preferably an optical sensor that is located close to said vacuum opening, enables the detection of the approach of an inlet edge located on the progress direction and an outlet edge located on the opposite side to the progress direction of the workpiece advanced during the sewing process, to said vacuum opening (2a).

The thread cutting system disclosed in another preferred embodiment of the invention comprises, in case said inlet edge approaches said vacuum opening (2a) in the direction of the information received from said sensor element that is in connection with said sensor element, in case said cutting element (6) approaches to said first cutting blade (3a) and said outlet edge approaches said vacuum opening (2a), a control element that provides control of the operation of said first movement element (7) and said second movement element (8) so as to bring said cutting element (6) closer to said cutting blade (3b).

The thread cutting system disclosed in another preferred embodiment of the invention comprises the following; at least one cutting element (6) that comprises at least two third cutting blades (6a) which is formed by sharpening a first edge positioned close to and parallel to said first cutting blade (3a) on the edge close to said vacuum opening (2a) and a second edge positioned close and parallel to said second cutting blade (3b), enables cutting said excess thread by approaching said first edge to said first cutting blade (3a) or said second edge to said second cutting blade (3b) and at least one interface between said first edge and said second edge, extends parallel to said vacuum channel (2), prevents the excess thread from twisting or jamming by pushing the cut excess thread towards said vacuum channel (2). Therefore, it is provided to shorten the movement distance of said cutting element (6) realized parallel to said vacuum channel (2) and to reduce the wear rate of said third cutting blades (6a) based on usage by obtaining a cutting element (6) with an integral structure that comprises said third cutting blades (6a) moved so as to cut the excess thread.

The excess thread is provided to be cut according to both the guillotine type and the horizontal type by means of the thread cutting system developed with the present invention, by moving said cutting element (6) that cuts the excess thread in a bidirectional manner and rotating the same around the direction of progress. Thus, excess threads on both sides of the work piece are provided to be cut effectively and to be transferred directly into said vacuum channel (2). Therefore, an efficient, effective and fast thread cutting system that prevents the excess thread from jamming/being stuck and eliminates extra effort of the user, increases the sewing quality by decreasing the occurrence of failure and reduces the process time, is achieved.