Flat Head Pin

A flat-head pin includes: (a) a pin shaft with a pin point; (b)a flat pin head affixed to an end of the pin shaft distal to the pin point; wherein the flat pin head is characterized by a cuboid shape, preferably a tapered cuboid shape with a plurality of transverse gripping ribs spaced a distance, s, from each other. The flat pin head is characterized by a tapered cuboid shape with a plurality of transverse gripping ribs spaced a distance, s, preferably wherein the distance s is relatively large and there are relatively few gripping ribs, such as 3-5 transverse gripping ribs.

TECHNICAL FIELD

The present invention relates to pins used in connection with sewing; and in particular, to pins with an easy-grasp head to facilitate their use.

BACKGROUND

Pins with improved heads for sewing applications are known in the art. For example, there is disclosed in U.S. Design Patent No. D860,633 a pin with an elongate tapered ribbed head. Further improvements to the tapered ribbed head are seen in U.S. Design Pat. Application No. 29/768,007 and International Patent Application No. PCT/US2022/011470. Flat head pins are popular in the marketplace, but prior designs were found inferior to the present invention and may have been perceived as being hard to pick up, hard to grip, manipulate or control, particularly when trying to penetrate tougher materials like denim.

SUMMARY OF INVENTION

There is provided in accordance with the invention a flat-head pin comprising:(a) a pin shaft with a pin point,(b) a flat pin head affixed to an end of the pin shaft distal to the pin point;wherein the flat pin head is characterized by a cuboid shape, preferably a tapered cuboid shape with a plurality of transverse gripping ribs spaced a distance, s, from each other.

It has been found in accordance with the present invention that a flat head pin characterized by a tapered cuboid shape with a plurality of transverse gripping ribs spaced a distance, s, from each other was vastly preferred by seamstresses over other flat-head pin designs, especially when distance s is relatively large and there are relatively few gripping ribs, 3-5 transverse gripping ribs, for example.

Still further features, advantages and further aspects will become apparent from the discussion which follows and the accompanying drawings.

DETAILED DESCRIPTION

Referring to the drawings, there is illustrated a flat-head pin15including a pin shaft20with a pin point22, a flat pin head24affixed to an end26of the pin shaft distal to pin point22. The flat pin head is characterized by a tapered cuboid shape28with upper and lower surfaces28a,28b,lateral surfaces28c,28d,inner surface28eand outer surface28fand a plurality of transverse gripping ribs30,32,34,36spaced a distance, s, from each other. The gripping ribs are transverse in that they are substantially perpendicular to pin shaft20.

The distance, s, is typically from 0.7 mm to 1.25 mm; suitably about 1 mm in a preferred embodiment. Flat pin head24has a thickness, t, of from 1 mm to 1.6 mm; suitably about 1.3 mm in a preferred embodiment as well as a length, L, of from 7 mm to 13 mm; suitably around 10 mm in a preferred embodiment.

Transverse gripping ribs30,32,34,36have a width, w, of from 0.5 mm to 1.0 mm; suitably about 0.75 mm in a preferred embodiment. The transverse gripping ribs project laterally as shown from flat pin head lateral surfaces28c,28da distance, d, of from 0.2 mm to 0.8 mm from the sides of the pin head and somewhat less from the upper and lower surfaces of the flat pin head. Distance d may be about 0.5 mm and generally from 1.0 to 2 times the distance the ribs project from the upper and lower surfaces of the pin head.

It is appreciated from the drawings that flat pin head24tapers from an inner characteristic width, iw, adjacent the pin shaft to a longer outer characteristic width, ow, wherein the widths refer to the distance across the upper and lower surfaces perpendicular to shaft20. Inner characteristic width of the flat pin head iw, is from 6 mm to 9 mm; suitably about 7-8 mm, while outer characteristic width of the flat pin head, ow, is from 7 mm to 10 mm with the proviso that ow is greater than iw. A taper thus occurs over a length L of the flat pin head.

Flat pin head24has an inner terminal portion40adjacent the pin shaft and an outer terminal portion42distal to the pin shaft. Widths44,46(transverse widths along upper and lower surfaces28a,28b) of the inner and outer terminal portions are greater than the width, w, of the gripping ribs.

Outer terminal portion42of the flat pin head has an arcuate outer edge.

Typically, the flat pin head has from 3-5 transverse gripping ribs, suitably 4 transverse gripping ribs. Note that that pin shaft20is centrally affixed to inner surface28eof flat pin head24, that is located at the midpoints of the thickness and width of flat pin head24head as shown inFIG.4.

Pin head24is preferably made of a thermoplastic polymer material. The thermoplastic polymer material is preferably chosen from heat-resistant thermoplastic polymers with a melting temperature greater than 200° C. Polypropylene and polyethylene, which have lower melting points, may not be sufficiently heat resistant to avoid damage from a hot iron which is a requirement in many sewing operations so that a garment is not damaged by molten resin. Suitable polymers include nylon polymers such as nylon 6 and nylon 6,6. The pinhead may be attached to the pin shaft by melt-bonding with or without an adhesive and/or surface roughening. For example, the pin head may be injection molded onto the shaft if so desired.

Seamstress Evaluation

The inventor provided 13 prior art flat-head designs (pins numbered1-13) and five new tentative designs (pins numbered14-18) to be evaluated for seamstress preference. The designs were evaluated by eight (8) seamstress panelists on a scale of 1-10 for utility and ease of use. The 8 seamstress were shown the pins independently—so as not to have any group/peer influence (in a group testing scenario, sometimes evaluators start to emulate the leader even if they have a different opinion on an item). All of the panelists selected the same pin as best, number15inFIG.7, giving it the highest rating of all the pins. The response was surprising, the panelists were all very impressed by the presently presented design of pin15(having the features and dimensions noted above) to the exclusion of the other flat-head pin designs. And that is what makes the selection of #15so fascinating—neither seamstress knew what the others had selected as it was tested independently—they all picked #15in an independent setting. The results were also surprising since pin18was substantially identical to pin15, except pin18had many more gripping ribs, spaced a distance of slightly less than 0.5 mm, whereas the rib spacing in pin15which was about 1 mm.