US3220221A

US3220221A - Pivoted latch knitting needle

Info

Publication number: US3220221A
Application number: US191197A
Authority: US
Inventors: William E Sheeler
Original assignee: Textile Machine Works
Current assignee: Textile Machine Works
Priority date: 1962-04-30
Filing date: 1962-04-30
Publication date: 1965-11-30
Anticipated expiration: 1982-11-30
Also published as: GB981975A; DE1585399A1

Description

2 Nov. 30, 1965 w. E. SHEELER PIVQTED LATCH KNITTING NEEDLE Filed April 30, 1962 3,220,221 PIVOTED LATCH KNITTING NEEDLE William E. Sheeler, Sinking Spring, Pa., assignor, by

rnesne assignments, to Textile Machine Works, Wyomissing, Pa., a corporation of Pennsylvania Filed Apr. 30, 1962, Ser. No. 191,197 1 Claim. (Cl. 66-121) This invention relates to pivoted latch needles for knitting machines and more particularly to an improvement in the structure of the head or hook of such needles.

In latch needles and particularly such needles for use in circular machines for knitting sheer tubular fabric such as for ladies stockings or the like, the upper or head end of the needle is provided with an overhanging hook having a circular cross section which must be as little as nineto ten-thousandths of an inch in diameter for the known fine gauge machines. In forming the fabric stitches the needle is raised during which a previously formed stitch opens the latch of the needle and is cleared below the lower end thereof and yarn for a new stitch is laid over the needle between the hook and the open latch. The needle is then lowered to form the new stitch during which the previously formed stitch closes the latch over the tip of the hook thereby permitting the latter stitch to be knocked over or oif the head of the needle. These raising and lowering movements of the needle in forming the fabric stitches which usually occur at high speeds, usually two hundred or more times a minute, cause vibration in the overhanging hook which when coupled with the light, rapidly repeated hammer-like blows on the tip of the hook as the latch is closed, rapidly fatigues the delicate structure of the hook and results in breakage thereof.

It is an object of the invention to provide a pivoted latch needle with a hook which is constructed to overcome the above mentioned and other defects and which will greatly increase the life of the needle in use.

Another object is to provide a pivoted latch needle with a hook having a substantially rectangular cross section, the width of the rectangular section corresponding to the normal permissible width of the hook of the needle and the height of the rectangular section being greater than the normal width of the hook.

A further object of the invention is to provide a method of forming a needle having a butt at one end thereof, and a hook at the other end thereof which is adapted to be closed by a pivoted latch, said method including the steps of forming the needle blank from material having a thickness greater than that normal for .the needle, reducing the material of the upper end portion of the blank from which the hook is to be formed in such a way that it becomes circular in cross section and has a diameter which is greater than the normal diameter of the material of the hook, bending the upper end portion to form the hook, and pressing the sides of the hook to change the cross-sectional shape of the material thereof from a circular to a rectangular shape having a width corresponding to the normal diameter of the material of the hook and a height which is greater than the normal diameter of the material of the hook.

With these and other objects in view, which will become apparent from the following detailed description of the illustrative embodiment of the invention shown in the accompanying drawing, the invention comprises the novel features of construction and method of producing the same, as hereinafter more particularly pointed out in the claims.

United States Patent ICC In the drawings:

FIGURE 1 is a side view on an enlarged scale of a pivot latch needle according to the instant invention;

FIG. 2 is a view on an enlarged scale of the upper or hook end of the needle at one stage of its formation;

FIG. 3 is a cross-sectional view taken along the line and in the direction of the arrows 3-3 of FIG. 2;

FIG. 4 is a view on an enlarged scale of the hook of the needle during another stage in its formation;

FIG. 5 is a view similar to FIG. 4 illustrating a further stage in the formation of the hook of the needle;

FIG. 6 is a view as seen from the right of FIG. 5; and

FIG. 7 is a cross-sectional view taken along the line and in the direction of the arrows 77 of FIG. 5.

Referring to FIG. 1 of the drawing there is shown a needle 10 having a shank portion 11, a butt 12 at the lower end of the shank, a hook 15 at the upper end of the shank, and a latch 16 mounted for pivotal movement adjacent to and adapted to cover the free end or tip of the hook. Commonly the needle, which is referred to hereinafter as gauge for purposes of comparison, is punched or blanked out of flat metallic stock having a thickness of twelve-thousandths of an inch with the butt and shank being formed of varying widths to strengthen these portions against both breaking and bending stresses during use. Following the forming of the blank the upper end is usually swaged or otherwise reduced to a circular cross-sectional shape of a diameter which is approximately nine-thousandths of an inch, the portion of the shank adjacent the upper end is shaped to receive the pivoted latch and the upper end is then bent to form the hook 15.

Needles as described above are used in circular knitting machines for the manufacture of fine gauge womens hosiery. Such machines normally have a cylinder diameter of 3% inches, the cylinders being slotted to receive 400 or more needles. The machines also comprising a sinker-head supporting a series of sinkers, one sinker being interposed between each adjacent pair of needles.

During the operation of the needle to form yarn stitches, the needle is raised to a high clearing level and yarn is laid over the needle between the hook 15 and latch 16 which is at this time in open position as indicated in FIG. 1. As the needle is then lowered the yarn is caught in the hook to be drawn or measured over the sinkers to form a stitch. As the needle is again raised to receive yarn for the next stitch the newly formed stitch is held by the sinkers and stripped downwardly along the needle to open the latch, if it has been closed, and as the needle continues to rise the new stitch is cleared below the end of the open latch and onto the shank of the needle. After the yarn is again laid over the needle between the hook and open latch, the needle is again lowered to form the yarn into a new stitch and draw it through the previously formed stitch. During this downward movement of the needle the previously formed stitch rides upwardly along the needle to close the latch over the tip of the hook and as the needle continues its downward movement to its lowest position the previously formed stitch passes upwardly over the closed latch and is knocked over the top of needle.

Because of the necessarily close spacing of the sinkers and the fact that the hook of each needle together with both legs of the stitch being formed thereby must be moved through the space betwen adjacent sinkers the maximum permissible width, i.e. the diameter in the conventional needle described above, of the material of the hook is limited. Normally in order to provide as much strength in the hook as possible the diameter of the material of the hook for the different fine needle gauges approximates the permissible diameter for the needle count in which a needle of that gauge is to be employed. Hereinafter such diameter or width will be referred to as the normal width. In 80 gauge needles usually employed in such machines such normal width is nine-thousandths of an inch as previously mentioned.

The repeated raising and lowering movements of the needles in -forming the stitches as described above, which may occur as many as two hundred or more times a minute, tend to set up a vibration in the hook and this vibration together with the slight hammer blows on the tip of the hook as the latch is closed, causes the delicate structure of the conventional hook to become fatigued and results in breakage thereof.

In order to increase the strength of the hook of the needle and thereby increase its resistance against fatigue without at the same time increasing its width beyond the normal width, the blank of the needle of the instant invention, the 80 gauge needle again being used for purposes of comparison, is preferably punched out of sheet material thicker than that normally used for a needle of such gauge, e.g. having a thickness of thirteen-thousandths of an inch which is the normal thickness of the material from which a coarser or 75 gauge needle is formed. The upper portion of the needle blank from which the hook 15 is to be formed is reduced by swaging to a circular cross-sectional shape of a diameter, indicated at A in "FIG. 2, of approximately eleven-thousandths of an inch. Following bending of the upper end of the blank to form the hook 15 as indicated in FIG. 4, the sides of the hook are flattened by pressing or the like to change the cross-sectional shape of the material thereof to substantially a rectangle (FIGS. 6 and '7) having a width indicated at B of approximately nine-thousandths of an inch which corresponds to the normal cross-sectional diameter of material of the hook of the usual 80 gauge needle as above set forth and the resulting displacement of material caused by the pressing action acts to increase the vertical dimension or height of the rectangular area, indicated by the dimension C in FIG. 7, from its original dimension of eleven-thousandths of an inch to approximately tWelve-thousandths of an inch.

Thus there is provided a needle of a predetermined gauge in which the thickness of the shank portion is slightly greater than the normal thickness of the shank for the same gauge needle and in which the material of the hook portion is reshaped from a circular cross section to a substantially rectangular cross section having a width which corresponds to the normal permitted cross-sectional diameter of the hook for a needle of this gauge and a height which is greater than the normal cross-sectional diameter of the hook.

It is to be understood that while the novel improvements have been described herein in connection with an gauge latch needle, the invention is not to be construed as limited to 80 gauge needles but as being applicable to any time gauge later needle in which the above mentioned problems are present.

The improvements specifically shown and described by which the. above described results are obtained can be changed and modified in various ways without departing from the invention herein disclosed and hereinafter claimed.

What is claimed is:

A pivoted latch knitting needle of a predetermined gauge having a shank, a butt at one end of said shank and a hook at the other end of said shank, and a pivoted latch for closing said hook, said shank and butt having a width between the sides thereof which is greater than the normal width of said needle of predetermined gauge, and said hook being substantially rectangular in cross section, the Width of said rectangle corresponding substantially to the normal width of said hook of said needle of predetermined gauge and the height of said rectangle being greater than said width.

References Cited by the Examiner UNITED STATES PATENTS 140,150 6/1973 Mayne 163-5 140,611 7/1973 Bullard 163-5 485,021 10/1992 Sprowles 66-123 2,685,787 8/1954 Noe 66121 2,854,836 10/1958 Morris 66-121 RUSSELL C. MADER, Primary Examiner.

DONALD W. PARKER, Examiner.