Not applicable.
Not applicable.
1. Field of the Invention
The present invention relates to the manufacture of equipment for sewing technologies and methods for the sewing industry, the embroidered goods industry, the knitted goods industry, the leather industry and the shoe industry. The present invention comprises a technology for obtaining multi-thread single-line shuttle stitches.
2. Description of Prior Art and Existing Problems
At present only one type of machine for producing a single-line shuttle stitch line and only one type of shuttle stitch is known: a double-thread shuttle stitch making said stitch line (U.S. Pat. No. 2,862,468: ornamental stitch sewing machines).
The availability of just one type of shuttle stitch strongly hinders the potential for changes in the parameters of the stitch, which are limited to changing the step of the stitch and the thread tension. A shuttle stitch is rarely used in the sewing of knitted goods due to its low elasticity. At the same time, the shuttle stitch is sufficiently reliable and has a nice finished appearance.
In addition, the contemporary chain stitch used in sewing knitted goods has good elasticity but is not very reliable, and tends to deform the seam, causing corrugation, which creates the appearance of a defect in the finished product.
Hence, there is a demand for combining the benefits of these two kinds of stitches in a new type of stitch.
Another problem in sewing technology is the optimization of stitch line properties along the length of the line. The loads to which the stitch is exposed are different in different areas of a sewn article. In addition, the conditions of the stitch line operation are different, whereas the stitch line remains uniform along its length. For example, an article, such as a sleeve, is subject to various deformations in different areas: stretching at the elbow and corrugation at the bend. Also, the uniform stitch line often joins several layers of material, while the materials can be heterogeneous (woven fabric, knitted fabric, leather, etc.). Thus, the average properties of the uniform stitch line are intended to cover variable requirements, which ultimately limits the technological possibilities of creating new goods without the existing difficulties.
Further, the shuttle stitch structure assumes uneven deformation under stretching, where alternating stretched and squeezed areas are created (stretched areas occur around the perforation in the material, i.e. in the point of conjunction of the top and bottom threads, while the squeezed areas occur in the interval between two perforations). Such uneven deformation of the seam causes corrugation.
Thus, the main drawbacks of the contemporary single-line shuttle stitch line, which limit its application and degrade its operational properties and the appearance of the finished product, are as follows:
The aim of the present invention is a further improvement in the class of the shuttle stitch, due to the elimination of the drawbacks described above, by using the following principles:
These and other objects and advantages of this invention are described in detail in the description of the invention contained herein.
The present invention comprises variations in the manufacturing of multi-thread single-line shuttle stitch lines, consisting of a system of top threads and a system of bottom threads, which threads are conjoined at the material perforation points. The top threads are joined with the bottom ones in a pre-determinable sequence, variable along the stitch line. This effect is obtained due to the following:
The proposed stitch line structure consists of a system of several top and several bottom threads joined through the perforations in the material. Such structure provides for mutual compensation of stretched and squeezed areas of the material and eliminates corrugation of the seam. Another benefit is the potential for changing or transforming the structure along the length of the stitch line in the process of the production of the stitch line. It permits the optimization of the properties of the seam in terms of its appearance, elasticity, wear resistance, etc.
The sequence of interaction of the top and the bottom threads is determined by the required structure of the stitches. The sequence of interaction can be controlled mechanically or digitally. These methods of control and programming are well known and widely used—e.g., in knitwear fabrics manufacturing (U.S. Pat. Nos. 4,467,737 and 4,359,953).
The loading of every upper thread into its needle and of every bottom thread into its shuttle can be provided by various methods used in conventional multi-thread sewing machines. (U.S. Pat. Nos. 3,433,191 and 4,993,335).
A means for sequentially engaging a required needle and a means for sequentially engaging a required shuttle at one moment, providing for conjunction of one of the top threads with one of the bottom threads, is not known from the prior art. These means could be provided by various ways. One of the ways is taught in the present invention. It comprises a needle unit (mechanism) and a shuttle unit (mechanism).
The needle unit is comprised of a revolver (needle revolver) with needle bars located along its periphery and oriented along its rotation axis. The shuttle unit also is comprised of a revolver (shuttle revolver), where the shuttles are similarly located along its periphery. Both revolvers are equipped with a device which provides for enabling the current couple. Both revolvers are provided with a means for turning and fixation. A Geneva wheel can be used for such purpose. (A Geneva wheel is a well-known mechanism in sewing machines; see, e.g., U.S. Pat. No. 4,702,183).
The utilization of both revolvers, due to the rotation of the needles and the shuttles around the rotation axes of the respective revolvers, can provide for the respective intertwining of the top threads with each other and of the bottom threads with each other.
The present invention can be easily understood from the detailed description of the preferred embodiment by reference to the attached drawings.
The principal steps of the multi-thread single-line shuttle stitch line formation cycle are as follows:
The cycles can be performed by the following mechanisms and devices. The mechanism for needle revolver discrete rotation (10) turns needle revolver (11), bringing desired needle (e.g., 5a) into operating position; the simultaneous mechanism of shuttle revolver discrete rotation (12) brings desired shuttle (e.g., 6a) into operating position; thus, the current couple of needle 5a and shuttle 6a is enabled. With this, the catching device (14) of mechanism (13) catches shoulder (15a), thus enabling needle bar (12a). The current couple then works in the manner of conventional sewing machines, i.e., as shown above in paragraphs 1, 2 and 3 of the principal steps of a multi-thread single-line shuttle stitch line formation cycle.
As described in paragraph 4 of the same, at the moment of the shift of the material for a small stitch (t), the mechanisms for the discrete rotation of needle revolver (10) and shuttle revolver (11) turn needle revolver (8) and shuttle revolver (9) respectively, bringing desired needle bar (any of the needle bars; e.g., (12b)) and desired shuttle (any of the shuttles; e.g., (6c)) into the operating position. (The remainder of the needle bars (12a) and the shuttles (6a and 6b) are idle at this moment, as the current couple (5b and 6c) only operates at the given moment.) After this, a new stitch is formed.
The sewing machine can be designed with:
The solid needle revolver (
The modular needle revolver (
The module (
While this invention has been described in terms of a specific embodiment thereof, it is to be understood that it is not limited thereto, but rather only to the extent set forth hereafter in the claims, which follow.