Sewing machine

Abstract

A sewing machine includes a presser foot (2) mounted pivotably about a horizontally aligned axis (1), which is configured to cooperate with an undertransporting apparatus disposed on a support area (3) for a material to be sewn, which includes two material sliders (4, 5) mounted movably with respect to one another for the continuous transport of the material in a feed direction. Both material sliders (4, 5) are configured to be extended horizontally when viewed in the feed direction both in a region before and in a region after the axis (1) of the presser foot (2).

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a sewing machine.

2. The Prior Art

A sewing machine of the type specified initially is known from DE 74 30 111 U1. This consists of a presser foot mounted pivotably about a horizontally aligned axis, which is configured to cooperate with an undertransporting apparatus disposed on a support area for a material to be sewn, which comprises two material sliders mounted movably with respect to one another for the continuous transport of the material in a feed direction. In this case, one material slider is located in front of the axis of the presser foot and the other material slider is located therebehind when viewed in the feed direction.

As has been shown, the material is not optimally transported in this solution, which is made particularly noticeable due to the fall of the folds.

SUMMARY OF THE INVENTION

It is the object of the invention to improve a sewing machine of the type specified initially.

This object is achieved with a sewing machine of the type specified initially by the features according to the invention.

According to the invention it is therefore provided that both material sliders are configured to be extended horizontally when viewed in the feed direction both in a region before and in a region after the axis of the presser foot.

In other words, the present invention differs from the sewing machine specified initially in particular in that the material sliders are configured to be significantly longer and each extend into the area of movement of the other material slider. This stipulation has the result that the rotatably mounted presser foot which forms the counterpart to the undertransporting apparatus is supported over its entire surface in each operating phase and consequently cannot tilt away as in the sewing machine specified initially.

Other advantageous further developments are discussed below.

BRIEF DESCRIPTION OF THE DRAWINGS

The sewing machine according to the invention including its advantageous further developments discussed below is explained in detail hereinafter with respect to the diagrammatic representation of a preferred exemplary embodiment.

In the figures

FIG. 1 shows in side view a part of the sewing machine according to the invention in a first position;

FIG. 2 shows the undertransporting apparatus according to FIG. 1 in a second position;

FIG. 3 shows the undertransporting apparatus according to FIGS. 1 and 2 in a third position;

FIG. 4 shows in perspective view the undertransporting apparatus according to FIGS. 1 to 3 and

FIG. 5 shows in perspective view as a detail the presser foot with the two material sliders.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

FIGS. 1 to 5 substantially show the so-called undertransport of the sewing machine according to the invention. For the sake of simplicity, reference is again made to the initially specified DE 74 30 111 U1 (see FIG. 1 there) with regard to the more precise arrangement thereof inside the sewing machine, wherein the further technical configuration, in particular the so-called upper transport, can also be designed differently in the sewing machine according to the invention.

The sewing machine shown in FIGS. 1 to 5 (in part) therefore consists of a presser foot 2 mounted pivotably about a horizontally aligned axis 1. This is disposed in a known manner above the axis 1 on a spring-loaded presser bar (not shown) and is configured to be vertically movable. Furthermore, the presser foot 2 is configured to cooperate with the undertransporting apparatus disposed on a support area 3 (shown indicated) for a material to be sewn (material, fabric or the like), which comprises two material sliders 4, 5 mounted movably with respect to one another for the continuous transport of the material in a feed direction, which are configured to be toothed on the material side in a known manner.

Furthermore (see FIG. 2), the presser foot 2 has a feed region 13 and removal region 14 for the material, which is curved away from the material sliders 4, 5, and a contact region 15 extending parallel to the material sliders 4, 5. In this case the axis 1 located transversely to the feed direction is hinged on the contact region 15 of the presser foot 2.

In addition (see FIG. 4) one of the two material sliders 5 is provided with a vertically extending through opening 16 for a sewing needle 17 (see FIG. 3).

It is now essential for the sewing machine according to the invention that both material sliders 4, 5 are configured to extend horizontally when viewed in the feed direction both in a region before and in a region after the axis 1 of the presser foot 2. The respective overhang on both sides is preferably about 1 to 2 cm.

As mentioned initially, this stipulation according to the invention advantageously has the result that the material during sewing is optimally further transported and in particular wrinkles are not formed.

It is particularly preferably provided that the material sliders 4, 5 which have approximately the same length as the presser foot 2 (when viewed in the feed direction), are formed from a plurality of rows of teeth 6 extending parallel to one another and intermeshing displaceably. With reference to FIG. 4, one material slider 4 is formed from two long rows of teeth 6.1 and one short row of teeth 6.2. The other material slider 5 is formed from one broad row of teeth 6.3 and two narrow rows of teeth 6.4 adjoining the broad row of teeth 6.3. Furthermore, the long rows of teeth 6.1 are disposed on both sides of the broad row of teeth 6.3 and the short row of teeth 6.2 is disposed displaceably between the two narrow rows of teeth 6.4. In particular, the short row of teeth 6.2 which is disposed (when viewed in the feed direction) in alignment with the through opening 16 for the sewing needle 17, has proved to be particularly advantageous since during sewing this presses the seam just produced against the presser foot 2 and thereby eliminates any lateral warpage of the material.

As can be seen from FIGS. 1 to 4, the material sliders 4, 5 are particularly preferably each disposed on a support element 7, 8, these in turn being configured to extend parallel to one another. In order to achieve space for the thread guide underneath the material sliders 4, 5, these (see in particular FIGS. 4 and 5) are arranged laterally parallel offset to the support elements 7, 8 by means of supporting plates 18, 19.

Furthermore, both support elements 7, 8 are each rotatably hinged on a crank 9 (preferably) at one of their ends (in FIGS. 1 to 4 on the left in the diagram) in order to achieve a horizontal movement of the material sliders 4, 5. In this case, the cranks 9 for the support elements 7, 8 are disposed on a common axis of rotation 10, wherein it is particularly preferably provided that the cranks 9 for the support elements 7, 8 are disposed on mutually opposite sides of the axis of rotation 10. As shown in FIGS. 1 to 3 which reproduce different turning positions of the axis of rotation 10 (slightly to the right, slightly to the left, central), this stipulation in particular in contrast to the aforesaid DE 74 30 111 U1 makes it possible for both support elements 7, 8 to be actuated with a single axis of rotation 10.

It is further provided that both support elements 7, 8 are each displaceably connected to a guide 11 (preferably) at their other ends (in FIGS. 1 to 4 to the right in the diagram) in order to achieve a vertical movement of the material sliders 4, 5. These guides 11 for the support elements 7, 8 are disposed on a common axis of rotation 12, wherein it is particularly preferably provided that the guides 11 for the support elements 7, 8 are disposed on mutually opposite sides of the axis of rotation 12 since in particular compared with DE 74 30 111 U1 this leads to a solution which is easier to produce from the production technology viewpoint and specifically in particular when the guides 11 are configured to be slit-shaped and guide elements 20 disposed on the support elements 7, 8 are displaceably mounted in these.

The basic functioning mode of the sewing machine according to the invention is already obtained from DE 74 30 111 U1 so that reference is made to this in this respect: the oscillating rotary movement of the axes of rotation 10 and 12 has the result that the material sliders 4, 5 move both horizontally and vertically and thereby transport the material in the feed direction, where the presser foot 2 serves as a counterholder and fixing for the sewing process with the sewing needle 17. Thanks to the intermeshing material sliders 4, 5 extending before and after the axis 1 of the presser foot 2, the material is optimally supported at each transporting time point, i.e. an undesired fall of the folds during sewing is effectively prevented.

REFERENCE LIST

• 1 Axis
• 2 Presser foot
• 3 Contact area
• 4 Material slider
• 5 Material slider
• 6 Row of teeth
• 6.1 Long row of teeth
• 6.2 Short row of teeth
• 6.3 Broad row of teeth
• 6.4 Narrow row of teeth
• 7 Support element
• 8 Support element
• 9 Crank
• 10 Axis of rotation
• 11 Guide
• 12 Axis of rotation
• 13 Feed region
• 14 Removal region
• 15 Contact region
• 16 Through opening
• 17 Sewing needle
• 18 Support plate
• 19 Support plate
• 20 Guide element

Claims

1. A sewing machine comprising a presser foot (2) mounted pivotably about a horizontally aligned axis (1), which is configured to cooperate with an undertransporting apparatus disposed on a support area (3) for a material to be sewn, which comprises two material sliders (4, 5) mounted movably with respect to one another for the continuous transport of the material in a feed direction,

2. The sewing machine according to claim 1, wherein the material sliders (4, 5) are formed from a plurality of rows of teeth (6) which extend parallel to one another and intermesh displaceably.

3. The sewing machine according to claim 1, wherein the material sliders (4, 5) are each disposed on a support element (7, 8).

4. The sewing machine according to claim 3, wherein the support elements (7, 8) are arranged extended parallel to one another.

5. The sewing machine according to claim 3, wherein both support elements (7, 8) are preferably each rotatably hinged at one of their ends on a crank (9) in order to achieve a horizontal movement of the material sliders (4, 5).

6. The sewing machine according to claim 5, wherein the cranks (9) for the support elements (7, 8) are disposed on a common axis of rotation (10).

7. The sewing machine according to claim 6, wherein the cranks (9) for the support elements (7, 8) are disposed on mutually opposite sides of the axis of rotation (10).

8. The sewing machine according to claim 3, wherein both support elements (7, 8) are preferably each displaceably connected to a guide (11) at their other ends to achieve a vertical movement of the material sliders (4, 5).

9. The sewing machine according to claim 8, wherein the the guides (11) for the support elements (7, 8) are disposed on a common axis of rotation (12).

10. The sewing machine according to claim 9, wherein the guides (11) for the support elements (7, 8) are disposed on mutually opposite sides of the axis of rotation (12).