KR102015312B1 - Sewing machine - Google Patents

Abstract

The sewing machine has a frame 15, a fabric support plate 16, and a needle bar 6 with sewing needles 7, which, together with other sewing parts, operate in a stitch forming area to form a seam. A transfer foot 20 attached to the transfer foot bar 22 is used to transfer the fabric 18 along the transfer direction T. A presser foot 21 attached to a presser foot bar 23 is used to clamp the fabric 18 against the support plate during the holding time within the stitch forming period. With respect to the support plate 16, the transfer foot (to alternately hopping the rise and fall of the transfer foot 20 on the one hand and the presser foot 21 on the other hand) 20 and the hopper mechanism 19 are connected to the presser foot 21. The hopper mechanism 19 is coupled via a hopper element 24 to the transfer bar 22, the presser foot bar 23 and the hopper drive 25. A joint connection of the hopper element 24 with the hopper drive 25 via a drive element 32 is constituted by a guiding groove 33, depending on the thickness of the fabric, without starting the hopper element 24. With respect to the drive element 32 on the one hand, on the other hand along the displacement path perpendicular to the support plate 16, there is a relative displacement of the transfer foot bar 22 and the presser foot bar 23. As a result, a sewing machine is provided having a hopper mechanism that is not substantially affected by the fabric thickness.

Description

Sewing machine {SEWING MACHINE}

The content of the German patent application DE 10 2012 207 257.8 is incorporated herein by reference.

The present invention relates to a sewing machine, and more particularly, to a sewing machine for stitching a durable sewing machine, that is, a very tough or very tough fabric.

Many different embodiments of sewing machines, in particular durable sewing machines, are known.

One object of the present invention is to provide a hopper mechanism connected to a presser foot for clamping the fabric and a transfer foot for conveying the fabric for alternating hopping of the rise and fall relative to the support plate. Is to develop a sewing machine so that it is practically not affected by the fabric thickness.

This object is achieved according to the present invention by the following sewing machine.

As a sewing machine,

-With frames,

Fabric support plate,

A needle bar with sewing needles which, together with other sewing parts, operates in a stitch forming area to form a seam,

A transport foot attached to a transport foot bar used to transport the fabric along a transport direction,

A presser foot attached to a presser foot bar used to clamp the fabric against the support plate during the holding time in the stitch forming period;

A hopper connected to the support foot and the presser foot for alternately hopping the rise and fall of the presser foot on the one hand and on the other hand to the support plate. ) Instrument

Including,

The hopper mechanism is coupled via a hopper element to the transfer bar, the presser foot bar and the hopper drive,

A joint connection of the hopper element with the hopper drive via a drive element is constituted by a guiding groove, depending on the thickness of the fabric, without starting the hopper element, on the one hand and on the other hand Relative displacement of the transfer foot bar and the presser foot bar is made along a displacement path perpendicular to the support plate,

The drive element is connected to the frame via a frame lever.

The hopper drive through the drive element with the guiding groove and the joint connection according to the invention of the hopper element ensure that the thickness or strength of the fabric to be sewn does not affect the hopper movement of the transfer foot and the presser foot. do. The transfer foot and the presser foot can be driven in the same way by a hopper drive for hopping up and down, even if it is a very thin or very thick fabric. The guiding groove of the joint connection of the hopper element with the drive element can be formed in the drive element or the hopper element. The frame lever connection, in which the drive element is connected to the frame via the frame lever, ensures reliable coupling of the drive element.

Via a first joint to the transfer foot bar,

Via a second joint to the presser foot bar,

The hopper mechanism configured as a triangular lever mechanism with a triangular lever as a hopper element coupled to the drive element via a third joint can be compactly formed with a relatively small number of mechanical elements.

In the sliding guiding groove in which the guiding bolt of the hopper element is guided, the drive element configured as the sliding groove plate is a robust variant of the drive element.

The slide block in which the guiding bolts are guided in the sliding guiding grooves avoids twisting in the area of the guiding grooves and reduces wear.

The hopper gear is connected to the hopper gear via the gear lever and the hopper drive shaft and can provide the hopper lift of the transfer foot bar and the presser foot bar, allowing the hopper drive to be adjusted to the individual sewing requirements. Let's do it. The hopper gear can be driven by the arm shaft of the sewing machine, and also the movement of other sewing components, in particular the needle bar, can be derived from this arm shaft. With the hopper gears, the hopper lifting can be particularly continuous. The frame lever connecting the drive element to the frame can form a parallelogram arrangement with the gear lever according to the invention. This kind of parallelogram arrangement is stable.

A driven pivotable needle bar frame in which the needle bar for fabric needle transfer can be pivotally driven by a needle bar frame connected to the frame via a needle bar frame coupling point is a robust possibility for transporting the fabric. . Fabric needle transfer of this kind can be arranged to be synchronized with the transfer foot movement.

The coupling of the frame lever, in which the frame lever is coupled to the frame by the needle bar frame coupling point, enables a compact structure. Then a separate frame holder for the drive element is not needed.

EMBODIMENT OF THE INVENTION Hereinafter, one Embodiment of this invention is described in detail with reference to drawings.
1 is a side view of the sewing machine seen from the operator's viewpoint.
2 is an exploded view of the hopper mechanism and the needle bar mechanism of the sewing machine.
3 shows the hopper mechanism and needle bar mechanism according to FIG. 2 in an assembled form, the fabric being 2 mm thick, for the support plate the presser foot in the upper position, the transfer foot in the lower position, the needle The bar is in the lower position.
4 is a view similar to FIG. 3 depicting the hopper mechanism and needle bar mechanism with the presser foot in the lower position, the transfer foot in the upper position, and the needle bar in the upper position relative to the fabric support plate. .
FIG. 5 shows the hopper mechanism and the needle bar mechanism in a position corresponding to that according to FIG. 3 except that the fabric thickness is 20 mm.
6 shows the hopper mechanism and the needle bar mechanism in the bar position according to FIG. 4, with the fabric thickness being 20 mm.
7 shows the presser foot reaching the lower position, the conveying foot also at the lower position and the needle bar between the lower and upper positions relative to the support plate, between the positions according to FIGS. 3 and 4. The hopper mechanism and the needle bar mechanism at the current position are shown in a description similar to that of FIGS. 3 and 4.
FIG. 8 shows the hopper mechanism and the needle bar mechanism in the bar position according to FIG. 7 except that the fabric thickness is 20 mm.

The sewing machine 1 shown in FIG. 1 includes a base plate 2 such as a housing, an upper arm 3, and a stand 4 connecting them. Therefore, the sewing machine 1 is composed of a C-shape as a whole. The upper arm 3 is equipped with an arm shaft 5, whereby the needle bar 6 with the needle 7 can be driven up and down by a crank drive, not shown in detail. By means of the arm shaft 5 via the shaft 9 and the belt drive 8 mounted on the base plate 2, a gripper mounted on the base plate 2 and assigned to the needle 7 is driven. Also not shown in detail. In cooperation with the needle bar movement, the gripper movement, as is already known, results in the formation of a seam in the stitch area.

 At the level of the belt drive 8 a flange section 10 is arranged on the arm shaft 5. By the flange section 10, the arm shaft 5 is rotatably connected in alignment with the drive shaft 11 of the arm shaft drive motor 12. Adjacent to the flange section 10, the drive shaft 11 is mounted by an axial / radial bearing 12a. The hand wheel 14 is coupled to the free end 13 of the drive shaft 11 and is also rotatably connected to the drive shaft 11 by a radial screw, not shown.

The sewing machine 1 is manufactured for sewing an rugged and / or strong fabric, in particular for sewing materials such as leather, very heavy cloth and / or panels such as plastic panels, for example.

The components of the sewing machine 1 are supported and mounted by the frame 15 of the sewing machine 1, the base plate 2 being part of the latter. The part of the base plate 2 is also a fabric support plate 16, which in turn is partly formed by the stitching plate 17. In the area of the stitching plate 17, the fabric 18 rests on the support plate 16 in the stitch forming area (see FIG. 2). In the latter area, the sewing needle 7 works with other sewing parts, for example a gripper, to form a seam.

2 shows an exploded view of the details of the hopper mechanism 19 and the needle bar mechanism 19a. The hopper mechanism 19 carries the transfer foot 20 for alternately hopping the rise and fall with respect to the stitching plate 17 of the transfer foot 20 on the one hand and the presser foot 21 on the other hand. (See FIG. 3) and the presser foot 21. The needle bar mechanism 19a is connected to the needle bar 6 and is part of the needle bar drive for needle transfer of the fabric 18, not shown.

To simplify the representation of relative positions, the Cartesian xyz coordinate system is used below. The x-direction extends to the right in FIG. 1. The y-direction extends into the drawing perpendicular to the plane of the drawing of FIG. 1. The z-direction extends upward in FIG. 1. The arm shaft 5 extends parallel to the x-direction. The z-axis is perpendicular to the support plate 16.

The conveying foot 20 is attached to the conveying foot bar 22 and used to convey the fabric 18 along the conveying direction T which extends in the positive y-direction, together with the sewing needle 7.

The presser foot 21 is attached to the presser foot bar 23 and used to clamp the fabric 18 against the stitching plate 17 during the holding time in the stitch forming period of the sewing machine 1. .

By the hopper element 24, the hopper mechanism 19 is coupled to the transfer foot bar 22 and to the presser foot bar 23 and the hopper drive 25. The hopper mechanism 19 is configured as a triangular lever mechanism with a triangular lever as the hopper element 24. By means of the first joint by the joint bolt 26, the triangular lever 24 is coupled to the conveying foot lever 27, which is conveyed by the conveying foot joint 28 to the conveying foot bar 22. Coupled. By means of the second joint by the joint bolt 29, the triangular lever 24 is coupled to the presser foot bar 23. In addition, a washer 29a is arranged between the hopper element 24 and the joint bolt 29. By means of the third joint and the slide block 31 by the joint bolt 30, the triangular lever 24 is coupled to the drive element 32 of the hopper mechanism 19. The drive element 32 transmits the drive movement of the hopper drive 25 to the triangular lever 24. The drive element 32 is configured as a sliding groove plate with a sliding groove 33, also referred to as a linear guide. The sliding groove 33 extends on the surface of the sliding plate 32 facing away from the person viewing FIGS. 2 to 6. 2 and 3, the sliding groove 33 is indicated by the dotted line. The sliding groove 33 extends approximately parallel to the z-axis, ie at the smallest possible angle.

The joint connection with the drive element 32, ie the hopper element 24 via the sliding groove plate, ie the hopper drive 25 of the triangular lever, is constructed on the basis of sliding or guiding groove 33, so that the fabric 18 Depending on the thickness of, i.e., depending on the fabric thickness, without activating the hopper element 24 by the hopper drive 25, on the one hand with respect to the drive element 32, on the other hand and also perpendicular to the support plate 16 Along the displacement path V (see the double arrow in FIG. 2 and the arrows in FIGS. 3 and 5) perpendicular to the stitching plate 17, there is a relative displacement of the transfer foot bar 22 and the presser foot bar 23. do.

To complete the hopper drive connection, the drive element 32 has a drive joint by a joint bolt 34, whereby the gear drive lever of the hopper drive 25 is pressed onto the drive element 32 by the presser foot lever 35. ) Is coupled in the form of. The presser foot lever 35 is rotatably connected to the presser foot shaft 36. The presser foot shaft 36 corresponds to the hopper drive shaft. The presser foot shaft 36 is driven by a presser foot gear 37, also referred to as a hopper gear. The hopper lift of the hopper drive 25 may be defined by the presser foot gear 37. This is caused by the rotational position of the gear adjustment shaft 38 of the presser foot gear 37. The presser foot gear 37 is movably connected to the arm shaft 5, as indicated by the dashed line in FIG. 2, by the eccentric connection 39 and the tension bar 40. The presser foot gear 37 is a tab gear having a plurality of gear tabs 41. The function of this tap gear is described in EP 2 330 241 A1 with an example of a stitch adjusting gear.

By the presser foot gear 37, the hopper lift of the hopper movement of the transfer foot bar 22 and the presser foot bar 23 can be performed in succession.

The drive element 32, ie the sliding groove plate, is connected to the frame lever 43 via an additional joint by a joint bolt 42. The frame lever is connected to the frame 15 of the sewing machine 1 shown in FIG. 2 via an additional joint by a joint bolt 44. This joint connection to the frame 15 of the frame lever 43 is also a connection point to the needle bar frame 45 which is part of the needle bar mechanism 19a. The needle bar frame 45 comprises a guiding sleeve section 46 on which the needle bar 6 and the conveying foot bar 22 are guided. To transport the fabric 18, the needle bar frame 45 is pivoted about a joint axis provided by a joint bolt 44 extending parallel to the x-axis via a needle bar drive, not shown. The joint bolt 44 provides a coupling point for the needle bar frame 45 on the one hand and for the frame lever 43 on the other hand.

The presser foot lever 35 on the one hand and the frame lever 43 on the other form a parallelogram arrangement with the drive element 32.

Pretensioning of the presser foot bar 23 towards the stitching plate 17 is performed by adjusting screws 47 acting on the presser foot bar 23 via the pretensioning spring 48.

In addition, in the exploded view according to FIG. 2, an additional joint holding clamp 49 is shown for axial play-free joint connection.

3 shows that the presser foot bar 23 is in the upper position, the transfer foot bar 22 is in the lower position, and the needle bar 6 is shown in the lower position in the relative position. The hopper mechanism 19 and the needle bar mechanism 19a of FIG. The transfer foot 20 in this position clamps the fabric 18 against the stitching plate 17 so that the fabric 18 can be reliably transferred.

In the view of the relative bar position according to FIGS. 3 and 4, the fabric 18 has a thickness of 2 mm.

Because of the relatively thin fabric 18, the transfer foot bar 22 in its lowered position, shown in FIG. 3, descends further in the negative z-direction over the stitching plate 17. This is because the hopper element 24 can be displaced with respect to the drive element 32 in the negative z-direction with the transfer foot bar 22 and the presser foot bar 23, so that the hopper lift of the hopper mechanism 19 Does not affect (see arrow V in FIG. 3).

FIG. 5 shows the relative bar position according to FIG. 3 of the transfer foot bar 22, the presser foot bar 23 and the needle bar 6 in the case of a very thick fabric 18 ′. The fabric 18 'has a thickness of 20 mm. As a result, the transfer foot 20 at its lower position clamping the fabric 18 'according to FIG. 5 is substantially displaced in the positive z-direction as compared to the position according to FIG. 3. The joint connection of the drive element 32 and the hopper element 24 is because the hopper element 24 can be displaced due to the linear guide through the sliding groove 33 in the positive z-direction (see arrow V in FIG. 5). This can be balanced.

The thickness of the fabrics 18, 18 ′ has no practical effect on the hopper movement, in particular on the hopper lift of the transfer foot 20 and the presser foot 21. Even for very thin fabrics, such as fabric 18, for example, or very thick fabrics such as fabric 18 ', transfer foot 20 and presser foot 21 are hoppers that hop up and down. It can be driven in the same way by the drive 25.

4 shows a presser foot bar 23 in the lower position where the presser foot 21 clamps the fabric 18 on the stitching plate 17, in the case of a thin fabric 18, and the transfer foot bar 22. And needle bar 6 show the relative bar position of the state in the upper position.

Between FIG. 3 and FIG. 4, the change in the relative position of the transfer foot bar 22 on the one hand and the presser foot bar 23 on the other hand is applied to the hopper drive 25 associated with the hopper mechanism 19. Happens by In comparison with FIG. 3, in FIG. 4, the presser foot lever 35 is pivoted counterclockwise about the axis of the presser foot shaft 36, thus pressing the presser foot lever 35, the drive element 32. And the parallelogram with frame lever 43 were thus pivoted. The drive element 32 carries the triangular lever, ie the hopper element 24, through the connection of the joint bolt 30 and the sliding groove 33 via the slide block 31, and the latter pivoting counterclockwise. Let's do it. This means that in FIG. 4 as compared to FIG. 3, the presser foot bar 23 is lowered and the transfer foot bar 22 is raised.

5 and 6 again show "presser foot bar 23 rising, conveying foot bar 22 lowering, needle bar 6 lowering" on the one hand (see FIG. 5) and "presser foot bar on the other hand". (23) shows the change between the relative bar position of the lowering, raising the feed foot bar 23, raising the needle bar 6 "(see FIG. 6). Because of the thick fabric 18 ′ compared to the application in FIGS. 3 and 4, the hopper element 24, ie the triangular lever, in FIGS. 5 and 6 is positive with respect to the drive element 32, ie with respect to the sliding groove plate. it is displaced in the z-direction (see arrow “V” in FIG. 5). By the principle of a parallelogram drive in which the hopper drive 25 acts on the hopper element 24 via the drive element 32, nothing changes. Thus, there is a hopper movement of the presser foot bar 23 and the transfer foot bar 22, which is not affected by the fabric.

In a variant that is not shown, guiding, ie sliding grooves, such as sliding groove 33, may be formed in the triangular lever 24. In this variant, a joint bolt with a slide block is arranged, in particular in the drive element 32.

7 shows that in the case of a thin fabric 18, the presser foot bar 23 is reaching the lower position, the conveying foot bar 22 is in the lower position and the needle bar 6 is lowered in accordance with FIG. 3. The relative bar position of the state between the position and the upper position according to FIG. 4 is shown.

8 shows the relative bar position according to FIG. 7 in the case of a thick fabric 18 ′.

Claims (7)

As the sewing machine 1,
A frame 15,
A fabric support plate 16,
A needle bar 6 with sewing needles 7 which, together with other sewing parts, operates in a stitch forming area to form a seam,
A transfer foot 20 attached to a transport foot bar 22 used for transporting the fabric 18; 18 'along the transport direction T,
A presser foot 21 attached to a presser foot bar 23 used to clamp the fabric 18 (18 ') against the support plate 16 during the holding time within the stitch forming period. )and,
The transfer foot for alternately hopping the rise and fall of the transfer foot 20 on the one hand and on the other hand the presser foot 21 on the support plate 16. 20 and a hopper mechanism 19 connected to the presser foot 21.
Including,
The hopper mechanism 19 is coupled via a hopper element 24 to the transfer bar 22, the presser foot bar 23 and the hopper drive 25,
A joint connection of the hopper element 24 with the hopper element 25 via a drive element 32 is constituted by a guiding groove 33, depending on the thickness of the fabric, of the hopper element 24. Of the conveying foot bar 22 and the presser foot bar 23 along the displacement path V perpendicular to the support plate 16 on the one hand, relative to the drive element 32 without maneuvering Relative displacement is done,
The drive element 32 is connected to the frame 15 via a frame lever 43,
The drive element 32 is connected to the hopper gear 37 via a gear lever 35 and a hopper drive shaft 36, by means of a hopper gear 37 the transfer foot bar 22 and the presser foot. Sewing machine, characterized in that the hopper lift of the bar (23) is provided. The method of claim 1,
The hopper mechanism 19 is, as the hopper element 24,
Is coupled to the transfer foot bar 22 via a first joint 26,
Is coupled to the presser foot bar 23 via a second joint 29,
Coupled to the drive element 32 via a third joint 30.
And a triangular lever mechanism having a triangular lever. The method of claim 1,
The drive element (32) is configured as a sliding groove plate, and the guiding bolt of the hopper element (24) is guided in the sliding guiding groove (33) of the sliding groove plate. The method of claim 3, wherein
The guiding bolt is sewing machine, characterized in that guided in the sliding guiding groove (33) through a slide block (31). The method of claim 1,
The needle bar 6 for fabric needle transfer can be pivotally driven by a needle bar frame 45 connected to the frame 15 via a needle bar frame coupling point 44. . The method of claim 5,
And the frame lever (43) is coupled to the frame (15) by means of the needle bar frame coupling point (44).
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