Patent Abstract:
A strip of bag clips are provided having individual clips each with a bag neck access opening joining a bag neck confining aperture within the clip. The bag neck access opening extends in a transverse direction relative to the length of the strip. Adjacent clips are joined together on adjacent sides via a central or medial and contiguously formed bridge portion defined by laterally formed slots. In one case, the clips are formed from a frangible material. In another case, the clips are formed from a flexible or resilient material. In a further case, the clips are formed from a biodegradable material.

Full Description:
RELATED PATENT DATA  
       [0001]     This application claims priority from U.S. Provisional Patent Application Ser. No. 60/605,185, which was filed Aug. 27, 2004, and U.S. patent application Ser. No. 10/835,327, which was filed Apr. 28, 2004, and which are incorporated by reference herein. 
     
    
     TECHNICAL FIELD  
       [0002]     This invention pertains to clips and arrays of clips for closing the necks of flexible bags. More particularly, the present invention relates to clips and strips of clips capable of being formed from flat material which can be separated by severing a connection between adjacent clips in a strip, including substantially flat material that is not necessarily brittle or frangible and can also be constructed from biodegradable materials.  
       BACKGROUND OF THE INVENTION  
       [0003]     It is previously known to form adjacent clips in a strip so that adjacent clips are attached together by way of narrow, frangible webs of relatively brittle material. Pursuant to U.S. Pat. Nos. 3,164,249; 3,164,250; 4,333,566; and 4,911,293, the clips are formed in strips that include such narrow, frangible webs of relatively brittle material. An individual clip is then either manually or machine manipulated so as to rotate and fracture a single clip from an adjacent clip in a strip, thereby breaking the webs of frangible material and separating an individual clip. However, such constructions are only suitable when clips are made from a relatively brittle, frangible material. Such clip construction is not suitable for use with relatively pliant and forgiving materials. Furthermore, the severing of individual clips in such manner can involve the production of stray chips of plastic or frangible material. These stray dips can be released by a random fracturing process which can contaminate food or other products within a bag, or can also cause malfunctioning of a clip-attaching mechanism. Furthermore, if the webs break in a relatively random manner and not in an intended manner, the webs can remain as sharp projections that protrude from the edge of a clip which can scratch or snag other products, or can scratch or snag the hands of a user or purchaser of the bag.  
         [0004]     U.S. Pat. No. 4,215,606 discloses an alternative construction that minimizes the length of breaking portions between individual clips in a strip. By making the breaking portions of a negligible longitudinal length, an effort is made to avoid the production of undesirable chips of frangible material or snagging projections which can produce the above undesirable results. However, such construction involves a relatively complicated technique using a punch and die anvil of shear tools in order to produce the appropriate clip configuration. Furthermore, the strip of clips is still constructed of a frangible material. Accordingly, such construction cannot appear to provide a construction suitable for use with non-frangible materials, such as biodegradable materials or flexible materials suitable for reuse.  
         [0005]     By way of example, U.S. Pat. No. 4,911,293 discloses a prior art strip  10  of clips  12 , such as clips  12   a - 12   d , which are formed together and which are subsequently severed from one another by bending and fracturing a frangible web connection either by hand or by using a mechanical apparatus, such as one of the machines utilized in U.S. Pat. Nos. 3,163,969 and 3,163,972. As shown in  FIG. 1 , each clip, such as clip  12   a , is provided with an aperture  14  that is accessed by a bag receiving passage  16  to receive a bunched-up open mouth portion of a bag where it is retained therein so as to close the bag. A pair of front surfaces  18  and  20  cooperate to form recessed portions that provide bag receiving passage  16 . More particularly, a pair of tapered, converging fingers  28  and  30  cooperate to provide bag receiving passage  16 .  
         [0006]     Clips, such as  12   a - 12   d , in strip  10  are held together with adjacent clips via pairs of internesting protrusions  22  and  24  which are provided on opposite lateral edges of each respective clip  12 . As disclosed within U.S. Pat. No. 4,911,293, adjacent protrusions  22  and  24  are actually integrally formed together by way of a relatively small segment of interconnecting material that is not visible in  FIG. 1 . Physical manipulation of a single clip, such as clip  12 , relative to a remaining portion of strip  10  causes severing of such segments between protrusions  22  and  24  so as to sever an individual clip  12 , either manually or by way of a machine. Additionally, pairs of projections  32  and  34  are provided within each aperture  14  to further ensure gripping of a bunched together mouth portion of a bag within aperture  14  when a bag is held in such aperture.  
         [0007]     The above-described techniques of bending and fracturing one or more frangible web connections will not work well on closure clips that are constructed of non-frangible materials, such as biodegradable materials and flexible or resilient materials. Accordingly, improvements are needed in light of the above-described deficiencies of the prior art presented herein.  
       SUMMARY OF THE INVENTION  
       [0008]     A strip of bag clips are provided having individual clips each with a bag neck access opening joining a bag neck confining aperture within the clip. The bag neck access opening extends in a transverse direction relative to the length of the strip. Adjacent clips are joined together on adjacent sides via a central or medial and contiguously formed bridge portion defined by laterally formed slots. In one case, the clips are formed from a frangible material. In another case, the clips are formed from a flexible or resilient material. In a further case, the clips are formed from a biodegradable material.  
         [0009]     According to one aspect, a closure clip unit is provided with a plurality of closure clips integrally formed in a strip of essentially flat material. Each closure clip has an aperture provided in the clip with an entrance to the aperture provided at a lateral edge of the strip, and a central tab integrally provided between each successive clip of the strip and a respective next adjacent one of the clips.  
         [0010]     According to another aspect, a strip of closure clips is provided having a plurality of closure clips integrally formed in a strip of biodegradable material.  
         [0011]     According to yet another aspect, a bag closure clip is provided with a closure body of thin, flexible biodegradable sheet material with a bag confining mouth and a narrow opening located in a longitudinal side edge and a contiguous web in a lateral side edge configured to be integrally formed with another closure clip in the form of a multi-closure strip. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0012]     Preferred embodiments of the invention are described below with reference to the following accompanying drawings.  
         [0013]      FIG. 1  is a side elevational view of a strip of clips according to a prior art construction;  
         [0014]      FIG. 2  is a perspective view of a roll of an elongated strip of dips according to one construction of the present invention;  
         [0015]      FIG. 3  is an enlarged, plan view of a strip of clips according to the present invention;  
         [0016]      FIG. 4  is a sectional view taken along lines  4 - 4  of  FIG. 3 . 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0017]     This disclosure of the invention is submitted in furtherance of the constitutional purposes of the U.S. Patent Laws “to promote the progress of science and useful arts” (Article 1, Section 8).  
         [0018]     Reference will now be made to a preferred embodiment of Applicant&#39;s invention comprising a clip and a strip of clips for closing flexible bags. While the invention is described by way of a preferred embodiment, it is understood that the description is not intended to limit the invention to such embodiment, but is intended to cover alternatives, equivalents, and modifications which may be broader than the embodiment, but which are included within the scope of the appended claims.  
         [0019]     In an effort to prevent obscuring the invention at hand, only details germane to implementing the invention will be described in great detail, with presently understood peripheral details being incorporated by reference, as needed, as being presently understood in the art.  
         [0020]      FIG. 2  illustrates a strip  110  of individual clips  112  according to one aspect of the present invention. Clips  112  are often referred to as closure clips. Each clip  112  has a central aperture  114  that communicates with a bag receiving passage, or a slit  116  that is provided in each dip  112  so as to extend in a lateral direction relative to strip  110 . According to one construction, strip  110  is formed from a relatively flexible material such as polypropylene. An alternative resilient or flexible material comprises a high impact polyethylene. Further alternatively, strip  110  of clips  112  can be formed from a biodegradable material such as paper, wax-impregnated paper, any of a number of wood fiber based products, biodegradable plastics, or other natural or biodegradable materials that break down when exposed to elements within the environment. Even further alternatively, strip  110  of clips  112  can be formed from a relatively brittle, frangible material, as previously utilized within the prior art techniques presently known within the field. Further alternatively, strip  110  can be formed from wood or metal, such as steel, aluminum, or copper.  
         [0021]     For the case where strip  110  is formed from a ductile material such as copper, one benefit of the present invention can clearly be discerned because copper is not frangible under tactile manipulation. More particularly, prior art techniques for severing individual clips from a strip will not work with a ductile material such as copper. However, the use of the strips and clips described herein can be implemented even with ductile materials when the clips are cut or severed from a strip by way of an automatic clip-applying machine. Prior art techniques utilize an automatic clip-applying machine that used a pusher with a rounded tip to displace one clip relative to another and to cause fracture between interconnections on adjacent protrusions. Such technique will not work well with a ductile material, such as copper.  
         [0022]     As shown in  FIG. 2 , strip  110  can be stored as a roll  150  in order to facilitate dispensing of individual clips  112  from strip  110 . For example, roll  150  can be incorporated into a rotary unwind apparatus of a clip dispensing machine that has opposed cutting edges that are driven together to co-act and sever individual clips  112  from strip  110  of roll  150 .  
         [0023]      FIG. 3  illustrates an enlarged detailed view of a selected portion of strip  110  showing a plurality of adjacently formed clips  112 .  FIG. 4  further illustrates such construction taken along section line  4 - 4  of  FIG. 3 .  
         [0024]     As shown in  FIG. 3 , strip  110  is formed from a single continuous piece of material, such as polypropylene or some other previously mentioned suitable material. One technique involves cutting strip  110  from a relatively thin sheet of material. Another technique involves stamping, machining, or laser cutting strip  110  from a sheet of material. Other techniques involve cutting strip  110  between a pair of intermeshing rotary cutting dies.  
         [0025]     In the forming process, individual clips  112  are contiguously joined together by way of a narrowed strip, isthmus, or web  152 . Each strip  152  is provided along a central, or medial portion of strip  110 , and a pair of laterally positioned slots  154  and  156  are provided immediately adjacent opposite sides of strip  152 , respectively. Accordingly, slots  154  and  156  cooperate to define strip  152  as being a relatively narrow strip between adjacent clips  112 , compared with a lateral width of strip  152 .  
         [0026]     Each clip has aperture  114  cooperating with a respective bag receiving passage  116  which is provided between a pair of opposed front surfaces  118  and  120 . Front surfaces  118  and  120  terminate in a converging pair of fingers  128  and  130  so as to provide a relatively narrow gap, or passage  116  into aperture  114  for receiving a bunched-up open neck portion of a flexible bag, such as a plastic bag.  
         [0027]     As shown in  FIG. 4 , individual clips  112  within strip  110  are shown with relatively narrow bag receiving passage  116  entering into aperture  114 . Likewise, the relative scale of slots  156  are shown with respect to a selected one of clips  112 .  
         [0028]     According to the construction depicted in  FIGS. 2-4 , it is understood that bag closure clips can be manufactured in a continuous strip and stored in a roll from non-frangible materials, such as biodegradable materials. Suitable biodegradable materials include paper, paper products, cardboard, and other traditional biodegradable materials. However, such a strip of closure clips can also be constructed from biodegradable plastics, such as biodegradable thermal plastics. Once such plastic is Polyactide (PLA), a biodegradable thermal plastic. Another material comprises Polyactic acid binder for joining together cellulose and other biodegradable materials. Even another material includes poly vinyl alcohol (PVOH). Even another material includes biodegradable polyester amide. An even further product includes a biodegradable polymer which is capable of being thermoformed.  
         [0029]     According to the construction depicted in  FIGS. 2-4 , a plurality of closure clips are integrally formed in a strip with a central tab integrally provided between adjacent clips. According to one construction, the central tab has a width of at least about 10 percent of the width of the strip. In some cases, the central tab has a width from about 20 percent to about 30 percent of the width of the strip. In even further other cases, the strip has a width of greater than about seven percent of the width of the strip. Furthermore, some further desirable constructions provide a central tab with a width of about 25 percent of the width of the strip.  
         [0030]     Construction of the central tab, or web, is configured to enable severing of clips from a strip using a pair of coacting cutting edges, such as cutting edges provided between a pair of complementary cutting dies. In contrast, prior art techniques utilize a finger that bends one clip relative to another in order to impart fracture of the frangible interconnecting webs provided between adjacent clips. The provision of such a central tab or web, which is configured to be cut between a pair of coacting cutting edges, enables the use of non-frangible materials, such as polypropylene, in constructing a strip of closure clips. Furthermore, such construction enables utilization of biodegradable material which tends to not be brittle or frangible, and which cannot be readily fractured using the prior art techniques discussed above. Accordingly, a strip of closure clips can be formed from a resilient plastic material, or from a contiguous sheet of biodegradable material.  
         [0031]     Furthermore, paper and paper products can be used to formulate such a strip of clips. For example, the provision of materials with a high content of wood fiber within paper or cardboard, along with an adhesive binder, enables the production of a fairly rigid strip of clips. Such strip of clips can be severed along the central connecting tab by a pair of coacting cutting edges by a clip cutting machine that is used to apply and sever clips from a strip during a bagging operation for products such as thermoformed articles, as well as food products.  
         [0032]     In compliance with the statute, the invention has been described in language more or less specific as to structural and methodical features. It is to be understood, however, that the invention is not limited to the specific features shown and described, since the means herein disclosed comprise preferred forms of putting the invention into effect. The invention is, therefore, claimed in any of its forms or modifications within the proper scope of the appended claims appropriately interpreted in accordance with the doctrine of equivalents.

Technology Classification (CPC): 8