JP4291972B2 - sewing machine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a sewing machine according to the superordinate concept of claim 1.
[0002]
[Prior art]
In the general type of sewing machine known from DE 3 144 966 C1, the knife is actuated to reciprocate up and down by means of a remarkably complex design of articulated lever system. In order to move the knife to the upper non-cutting position and the lower cutting position, a two-position linear drive in the form of a pneumatically actuated double action piston / cylinder drive is provided, which pivots the entire lever system Move.
[0003]
[Problems to be solved by the invention]
The object of the present invention is to embody a general type of sewing machine so that a simple way can be taken to move the knife from an upper position to a lower position and in the opposite direction.
[0004]
[Means for Solving the Problems]
According to the invention, this problem is solved by the features of claim 1. The gist of the present invention is that the two-position linear drive is a coupling mechanism that operates between the guide rod carrying the knife and the crank or eccentric drive. Thus, the connection mechanism can be extended and shortened.
[0005]
Advantageous embodiments will become apparent from the dependent claims.
Details of the invention will become apparent from the following description of exemplary embodiments in conjunction with the drawings.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
A two-needle sewing machine is schematically shown in the drawing and has, as is conventional, an upper arm 1, a lower floor plate 2 of a housing type, and a vertical stand (support) 3 connecting them. As usual, a needle bar (needle rod) 5 is mounted on the arm 1 for vertical displacement in the vertical needle bar guide 4; the arm shaft (not shown) is moved by a motor (not shown) as is conventional. It can be driven to reciprocate up and down via a crank (not shown). At its lower end, the needle bar 5 has two needles 6, 7. Assigned to the needles 6 and 7, a needle plate 8 is arranged on the upper side of the floor plate 2, and a hook (not shown) is arranged below the needle plate 8.
[0007]
A vertical knife guide 9 is arranged on the arm 1, a vertical guide rod 10 is guided to the guide for vertical displacement, and a knife 12 is installed at the lower end of the connecting piece 11. A pair of knives 13 is assigned to the knife 12, and the knife 13 is formed on the needle plate 8, for example, at the edge of the slit 14. The knife 12 extends through the slit and sinks into the needle plate 8.
[0008]
With respect to the sewing material conveyance direction 14 a shown in FIG. 2, the knife 12 is arranged downstream of the needles 6 and 7. As seen in the transport direction 14a, the knife is centered between the two needles 6 and 7, as shown in FIG. Aligned with the needle plate 8, the sewing machine has a support plate 15 for the material to be sewn. There is a first material, such as a jacket front, placed on the support plate 15. A second material 17, for example a piping piece, is placed on it. A third material 18, for example a flap, is further placed on only one side. These three blanks 16, 17, 18 are sewn together by a two-needle sewing machine and are simultaneously separated by corresponding cutting movements of the knife 12 in cooperation with a pair of knives 13 to form a slit (not shown). . Except for the guide rod 10, the two-needle sewing machine described so far is well known, for example, from DE 42223966 C1 (corresponding to US Pat. The document also teaches the previously described inserts for slitting material 16, 17, 18 sewn together and stitched together in a pocket flap.
[0009]
The cutting action of the knife 12 due to the up and down movement of the knife 12, which is not well known about this, is brought about by a knife drive electric motor 19 mounted on the arm 1. The motor directly operates the extension feed drive device 21 substantially vertically by a crank or eccentric drive mechanism 20. The feed drive device 21 is connected to the guide rod 10 by a joint 22, that is, it constitutes a coupling mechanism between the drive mechanism 20 and the guide rod 10. In the vicinity of the joint 22, that is, at a distance above the knife guide 9, the guide rod 10 is guided by the guide piece 23 so as to be displaceable on the vertical guide rail 24. By means of the guides 9, 23, 24, the guide rod is protected against deviations which intersect the vertical and longitudinal direction of its displacement and against rotation about its longitudinal axis.
[0010]
The feed drive device 21 is a two-position linear drive device. It is a double-action piston-cylinder drive device operating pneumatically, the housing 25 has a bearing 26, the crank or crank to the so-called prospect that the eccentric pin 27 is mounted in the eccentric drive mechanism 20 (eyelet). A piston 28 acting on both sides is disposed in the housing 25 for longitudinal displacement of the feed drive 21; a piston rod 29 is mounted on it and exits the housing 25 on the opposite side of the bearing 26. It extends and is sealed towards the housing. The piston rod 29 is connected to the joint 22 near its outer free end. In the vicinity of both ends, the compressed air pipes 30 and 31 communicate with the housing 25 and are operated by solenoid valves 32 and 33. The solenoid valves 32 and 33 and the drive motor 19 are operated by a joint control unit 34. The compressed air is supplied from a compressed air source (not shown).
[0011]
When the feed drive 21 is actuated by a compressed air pipe 30 (which is the lower pipe in FIG. 2), the piston rod 29 is retracted into the housing 25 shown in FIG. 2 (shown in solid lines in FIG. 2). There is a knife 12 in the upper position, it does not engage with the blanks 16, 17, 18 and the operator is not damaged by the knife 12.
[0012]
However, when the compressed air pipe 30 is released and the compressed air pipe 31 is actuated, the piston rod 29 moves down the housing 30 and moves the guide rod 10 with the knife 12 downward, as indicated by the dotted line in FIG. Press to the indicated cutting position. If the drive motor 19 is switched on at the same time, the knife 12 performs a vertical cutting motion in the vicinity of the paired knife 13 and cuts slits in the three materials 16-18 sewn together. The operation of the drive motor 19 and the feed drive device 21 is configured in the control unit 34 and is connected to the sewing drive mechanism of the sewing machine so that the vertical cutting motion by the drive motor 19 is only at the cutting position extending below the feed drive device 21. At the same time, it is carried out only when the materials 16, 17, 18 are sewn simultaneously. If the knife 12 is moved to the upper non-cutting position (which is also the rest position at the same time), the blanks 16 to 18 are not disturbed on the support plate 15.
[Brief description of the drawings]
FIG. 1 is a view with a part of a partial side view of a sewing machine according to the present invention taken along arrow I in FIG. 2 removed.
2 is a partially opened front view of the sewing machine according to the arrow II in FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Upper arm 2 Floor board 3 Stand 5 Needle bar 6,7 Needle 10 Guide rod 12 Knife 15 Support plate 16,17,18 Sewing material 19 Drive motor 20 Crank thru | or eccentric drive mechanism 21 Feed drive device

Claims (6)

Upper arm (1); lower the floor plate (2): upper Kia over beam (1) and the floor plate stand to bind (2) (3), at least one material (16, 17, 18) A support plate (15) assigned to the floor plate (2); a needle bar (5) attached to the arm (1) and movable up and down and having at least one needle (6, 7); A knife (12) attached to the arm (1) and movable up and down to cut a slit in at least one material (16, 17, 18); and connected to a drive motor (19) to cut the knife (12) up and down In a sewing machine comprising a crank or eccentric drive mechanism (20) for generating movement; and a two-position linear drive ( 21 ) for moving the knife (12) to a lower cutting position and an upper non-cutting position ,
The knife (12) is attached to a guide rod (10 ) movably attached to the arm (1); and a two-position linear drive for displacement of the guide rod (10) with the knife (12) The sewing machine is characterized in that the device ( 21 ) is arranged as a coupling mechanism between the crank or eccentric drive mechanism (20) and the guide rod (10). 2. The sewing machine according to claim 1, wherein the two-position linear drive device ( 21 ) is a double action piston / cylinder drive device that operates by air action.   The sewing machine according to claim 2, wherein the housing (25) of the two-position linear drive device is connected to a crank or an eccentric drive mechanism (20). The sewing machine according to claim 2 or 3, wherein the piston rod (29) of the two-position linear drive device ( 21 ) is connected to the guide rod (10) by a joint (22).   The sewing machine according to any one of claims 1 to 4, wherein the crank or eccentric drive mechanism (20) is directly mounted on the drive motor (19). Sewing machine according to any one of the preceding claims, characterized in that the control unit (34) is provided for common control of the two-position linear drive ( 21 ) and the drive motor (19). .

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