WO1997016085A1

WO1997016085A1 - Anti-vibration hand covering

Info

Publication number: WO1997016085A1
Application number: PCT/US1995/014162
Authority: WO
Inventors: Jasper N. Smith
Original assignee: Marmon Holdings, Inc.
Priority date: 1995-11-03
Filing date: 1995-11-03
Publication date: 1997-05-09

Abstract

An anti-vibration hand covering (10) having resilient cushions or pads (12, 14, 16, 18, 20, 22, 24, 26, 28) on the palm side of the hand covering formed of cured foamed plastisol, the pads (12, 14, 16, 18, 20, 22, 24, 26, 28) being formed in a predetermined pattern to enhance flexing of the hand when grasping a vibrating object.

Description

ANTI-VIBRATION HAND COVERING

BACKGROUND OF THE INVENTION

This invention relates to providing a resilient cushion between the grasping surface of a hand and a vibrating object being gripped by the hand, so as to lessen the undesirable transmission of vibrations to the hand. More particularly it relates to providing a hand covering such as a mitten, a glove or a partial glove, with resilient cushioned areas on the palm surface, which significantly reduces the transmission of vibrations from an object being held in the hand to the hand. It further relates to methods for forming the resilient cushioned areas or pads.

Cushioned hand coverings, such as gloves, have been provided in the past for reducing the transmission of vibrations from an object being held in a hand to the gripping surface of the hand. Typically the cushioning has been provided in the form of a layer of cushioning material incorporated in the construction of the glove. For instance, sheets of shock absorbing materials have been cut to conform to the shape of the material forming the palm surface of the hand and sown into the glove as the glove parts are assembled. One particular material which has been used for this purpose is Sorbophane, manufactured by Sorbophane Inc. Another is Viscolas, manufactured by EAR Specialty Composites, a division of Cabot Safety Corporation. The incorporation of the sheet of shock absorbing material into a glove not only increases the complexity of assembling the glove and therefore its cost of production, but also the above-mentioned shock absorbing materials are relatively expensive.

Since the sheet of shock absorbing material is held in place by the stitching used to assemble the glove, it is customary for the sheet to cover the entire palm surface. The shock absorbing material necessarily being rather thick, so as to provide the desired cushioning effect, the gloves are somewhat bulky and resistant to bending around an object to be grasped. Anti-vibration hand coverings such as in the form of mittens or gloves, are used when grasping objects which transmit vibrations to the hand. Examples of such objects are jack hammers, vibrating compactors, the metal handles of impact tools, etc.

SUMMARY OF THE INVENTION

It is an object of this invention to provide an anti-vibration hand covering such as a glove which is simpler to manufacture than prior art anti-vibration gloves. It is another object of the invention to provide a method of manufacturing an anti-vibration hand covering which may be used with a wide variety of glove materials and constructions. That is, with various types of sheet materials sown or otherwise joined to form a hand covering, and also hand covering formed of fibers knitted in the shape of a hand covering. It is a further object of this invention to provide a variety of methods of forming anti-vibration pads on material forming the palm surface of a hand covering. It is a still further object of this invention to provide an anti- vibration hand covering which is less expensive to manufacture than currently manufactured anti-vibration hand coverings.

In accordance with this invention, an anti-vibration hand covering is provided which is readily manufactured using a wide variety of materials and construction methods to form the hand covering. Whatever the material used to form the hand covering, cushioning anti-vibration pads are formed on the palm surface of the material by depositing thereon a foam plastisol in a predetermined pattern, which is then cured to form the desired anti-vibration pads. The use of a foam plastisol to form the anti-vibration pads lends itself to a variety of techniques for forming the pads. In a first method of forming the pads, a template having openings formed therein in the desired predetermined pattern of the pads is placed over the material forming the hand covering palm surface. The foam plastisol is then applied to the template which is of a predetermined thickness. A squeegee type device is passed over the template to provide the foam plastisol in a predetermined thickness in the openings. The foam plastisol upon curing expands to form pads of a predetermined thickness. Still other methods of applying the foam plastisol to the underlying material forming the palm surface of the hand covering include the ejection of the foam from a nozzle which is programmed to traverse a predetermined pattern over the underlying material to form the desired pads. The foam may also be applied to the underlying material by forcing it through a screen having the desired pad shapes formed therein. The foam plastisol used to form the resilient cushioned areas or pads in accordance with this invention is preferably a mechanically frothed PVC dispersion. While chemical blowing agents are commonly used for preparing plastisol foam, plastisol foam mechanically frothed by the use of a continuous roamer or mixing head that mechanically aerates or froths the plastisol prior to its delivery to the underlying material is preferred. The mechanically frothed plastisols are characterized by a high percent foam, which is required to provide the desired resilient cushioned areas or pads. By "high percent foam" is meant in excess of about 25% foam, preferably is excess of about 40 to 45% foam. The high percent foam when cured in accordance with conventional procedures, such as in an oven, will result in a solid microcellular foam having a uniform, closed cell structure. This uniform closed cell structure has enhanced compression recovery, which is a very desirable feature for a material forming a resilient cushioned area or pad.

More conventional foamed plastisols, for instance those foamed by chemical blowing agents normally do not have the desired uniform closed cell structure. Rather, they are more sponge like, and therefore do not have the enhanced compression recovery of a closed cell structure. The open cells of a more conventionally foamed plastisols will absorb liquid materials. Further, due to the open cells, the surface is normally rough, such that they have bee used on the gripping surface of gloves used to handle wet materials. The open cells absorb the liquid form the surface to be grasped, and the rough surface assists in grasping the wet material. While useful for that purpose, conventionally foamed plastisols do not provide the desired resiliency for forming cushioned areas or pads in accordance with this invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an elevation view of the palm face of a glove in accordance with this invention.

FIG. 2 is a cross-sectional view of the glove shown in FIG. l, taken along the line 1-1 in FIG. 1. FIG. 3 is a perspective view showing a first method of making a padded glove in accordance with this invention.

FIG. 4 is a perspective view showing a second method of making a padded glove in accordance with this invention. FIG. 5 is a perspective view showing a third method of making a padded glove in accordance with this invention.

DETAIL DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIG. 1, an anti-vibration hand covering in accordance with this invention, in the form of a glove, will be described. The palm face of a glove 10 of knit construction is shown being provided with anti-vibration cushioning pads 12 through 28. The cushioning pad 12 is provided on the thumb portion of the glove, the cushioning pads 14 through 20 and the palm portion of the glove, and cushioning pads 22 through 28 are provided on the fingers in the region of the first joints of the fingers. The cushioning pads 14 through 20 on the palm are formed with narrow spaces therebetween to permit the normal flexing of the palm when grasping an object. While a particular arrangement and spacing of the pads 14 through 20 is shown, other spacing and shapes which will provide for the flexing of the palm and fingers are contemplated by this invention. As compared to the prior art gloves which used a sheet of cushioning material covering the entire palm face of the glove, the provision of spacing between the pads formed on the palm surface, in accordance with this invention, is important for permitting flexing of the hand when grasping an object. While this invention has been illustrated in FIG. 1 in the embodiment of a glove, the invention may also be embodied in a mitten, a glove with only partial fingers, and even a hand covering which only covers the palm service and is held thereon by straps or other means passing over the back of the hand and possible of the fingers.

Referring to FIG. 2, a cross-section of the pads along the line 2 - 2 in FIG. 1 is shown. The cross-section shown in FIG. 2 is not intended to accurately represent the thickness of the underlying glove material or the thickness of the pads.

Referring to FIG. 3, one method of forming the anti- vibration pads in accordance with this invention will be described. A metal template 30, approximately 1/8" thick, is laid on top of the glove 10 which is held in a predetermined shape by a suitable form. The template 30 is provided with holes in the shape of the pads to be provided on the palm surface of the glove. A plastisol foam 32 is then dispensed on top of the plate and is leveled off by a squeegee 34 having a wiping blade 36 which levels the foam 32 with the top or upper surface of the template 30. The plastisol foam, after being applied in a 1/8" layer, that is the thickness of the template 30, will expand upon curing to a thickness of 3/16" to 1/4". By the term "plastisol" is meant a dispersion of a suitable polymeric substance in a liquid plasticizer. A commonly used polymeric substance for making plastisols is polyvinyl chloride and its copolymers. Plastisols typically contain additive agents such as stabilizers, pigments, fillers and processing aids. A plastisol desirable for use in accordance with this invention is one characterized as being formed with a high percentage foam. Further, when cured by conventions procedures, it results in a microcellular foam with a uniform closed cell structure. For a more complete understanding of plastisols of the type suitable for forming resilient pads in accordance with this invention, and a method of dispensing plastisol foams, reference is made to U.S. Patent No. 5,334,622, issued August 2, 1994 to Robert C. Bergvist and assigned to Rutland Plastic Technologies, Inc. The teaching of that patent are incorporated herein by reference.

Referring to FIG. 4, another method of forming the anti-vibration pads in accordance with this invention will be described. Again, the glove 10 is held in a predetermined shape by a suitable form. A nozzle 38 is provided to dispense a metered flow of plastisol on the palm surface of the glove 10. The movement of the nozzle over the palm surface of the glove is controlled so as to dispense the plastisol in a pattern providing the desired shape of the pads. Flow of plastisol from the nozzle may be interrupted as the nozzle position is moved from one pad to another. By coordinating the flow volume of the plastisol and the speed of movement of the nozzle with respect to the glove, the desired thickness of plastisol may be apply to the glove. It should also be recognized the either the glove or the nozzle can be fixed in position and the other moved with respect the fixed, so as to form the desired pads. Referring to FIG. 5, still another method of forming the anti-vibration pads in accordance with this invention will be described. Again, the glove 10 is held in a predetermined shape by a suitable form. According to this method a screen 40 having open cells in the areas to be provided with a pad, and impervious in other areas is placed over the glove 10. A squeegee similar to that shown in FIG. 3 is used to spread the plastisol over the screen and press it through the open cells to form the desired pads.

While the shock absorbing material is shown on the surface of the palm side of the glove in FIG.l, it may as well be applied to the outside palm surface of a glove liner. Thus, when the liner is incorporated within a completed glove, it will be enclosed between the outer layer and the liner of the glove. While one embodiment of the anti-vibration hand covering of this invention has been shown, as well as several methods of manufacturing the anti-vibration hand covering in accordance with this invention, it should be apparent to those skilled in the art that what has been described is considered at the present to be a preferred embodiment of the anti- vibration hand covering and the methods of making it in accordance with this invention. Changes may be made in the anti-vibration hand covering and the method of making it in accordance with this invention without actually departing from the true spirit and scope of this invention. The following claims are intended to cover all such changes and modifications which fall in the true spirit and scope of this invention.

Claims

CLAIMS What is claimed:

1. A method of manufacturing an anti-vibration hand covering having a padded surface comprising the steps of:

A. Selecting the material from which the portion of the glove which is to be padded is to be formed, B. support said material such that one surface of said material is exposed,

C. apply a foamed plastic to said surface of said material in a predetermined pattern,

D. curing said foamed plastic to provide a microcellular foam having a generally uniform closed cell structure, thereby providing a padded surface in the form of a resilient cushion having said predetermined pattern.

2. The method of manufacturing an anti-vibration hand covering having a padded surface of claim 1, wherein said foamed plastic is applied to said surface of said material in a predetermined pattern through openings in a template.

3. The method of manufacturing an anti-vibration hand covering having a padded surface of claim 1, wherein said foamed plastic is applied to said surface of said material in a predetermined pattern by moving a nozzle dispensing said foamed plastic with respect to said material.

4. The method of manufacturing an anti-vibration hand covering having a padded surface of claim 1, wherein said foamed plastic is applied to said surface of said material in a predetermined pattern by pressing said foamed plastic through a screen having the predetermined pattern formed thereon.

5. The method of manufacturing an anti-vibration hand covering having a padded surface of claim 1, wherein said foamed plastic is mechanically frothed with gas under a pressure in excess of atmospheric pressure prior to being applied to said surface of said material.

6. A padded hand covering comprising,

A. a hand covering formed of a suitable material,

B. a layer of foamable plastic deposited on said suitable material in a predetermined pattern on the area of the hand covering to be padded, said layer of foamable material, when cured forming a microcellular foam having a generally uniform, closed cell structure which adheres to said suitable material.

7. The padded hand covering of claim 6, wherein said hand covering is a glove, and said layer of foamable plastic is provided on the portion of said suitable material forming the palm of said glove.

8. A resilient cushion for reducing the transmission of vibrations from an object being gripped by a hand to the hand comprising:

A. a material providing a surface for covering the palm of a hand and means for retaining the surface on a hand,

B. a resilient cushioning material, in the form of a microcellular foam having a generally uniform closed cell structure, secured to and covering at least a predetermined portion of said surface, thereby reducing the transmission of vibrations to the hand from on object being held by the hand.

9. The resilient cushion of claim 8, wherein said resilient cushioning material is a cured mechanically frothed plastisol foam.

10. The resilient cushion of claim 8, wherein said resilient cushioning material is provided in a predetermined pattern which provides for the normal flexing of the palm of the hand when grasping an object.