Abstract:
An advanced sound reducing tape includes a surface treatment which results is reduced noise when the surface treatment comes into contact with various materials. The surface treatment comprises an arrangement of ridges and depressions disposed across a surface of the tape. The tape is vinyl based and therefore low in cost while providing a similar noise reduction as convention cloth tapes. The tape is typically utilized on a harness within an automobile and reduces squeaks when the harness including the tape comes into contact with interior portions of the vehicle which are typically polypropylene, ABS plastic or steel.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims priority under 35 U.S.C. § 119(e) to provisional application Ser. No. 60/014,919 filed on Apr. 10, 1996. 
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not applicable 
     BACKGROUND OF THE INVENTION 
     Tape is used in applications such as part of a wiring harness for an automobile. Ideally, the tape produces no sound when rubbed against various surfaces with which the wiring harness including the tape may come into contact. Typically cloth tape has been utilized which, while providing an acceptable level of sound which is below the level of human hearing when frictionally contacting other surfaces, is relatively expensive when compared to vinyl tapes. Vinyl tapes have been utilized which include a variety of surface finishes such as a smooth surface finish, a satin surface finish, a dull surface finish and a micro surface finish; however all of these vinyl tapes, while being lower in cost than cloth tape, produce unacceptable levels of noise when frictionally contacting various surfaces of a vehicle. 
     BRIEF SUMMARY OF THE INVENTION 
     The invention relates to an advanced sound reduction tape or anti-squeak and rattle (ASR) tape which produces a low level of sound when the tape is rubbed against another material or itself. The tape includes a surface treatment which provides for the reduce level of sound when the tape is brought into frictional contact with other materials. The tape is typically utilized as part of a wire harness within an automobile. The tape provides the noise reduction required at a low cost. 
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
     The invention will be more fully understood from the following detailed description taken in conjunction with the accompanying drawings of the invention in which: 
     FIG. 1 is an isometric view of the ASR tape of the present invention; 
     FIG. 2 is a photomicrograph of the surface treatment of the ASR tape at 30 times magnification; 
     FIG. 3 is a photomicrograph of the surface treatment of the ASR tape at 63 times magnification; and 
     FIG. 4 is a graph of the cost of the ASR tape compared to other tapes. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     An advanced sound reduction or anti-squeak and rattle (ASR) tape is disclosed. In the preferred embodiment the ASR tape is vinyl based, though other materials such as plastic based materials or rubber based materials could also be implemented. The ASR tape includes a surface treatment which provides for reduced sound when the surface of the tape is rubbed against a material. 
     Referring now to FIG. 1 an isometric view of the ASR tape 10 wound on a roll 16 is shown. The ASR tape 10 includes a substrate 12 of, for example, polyvinyl chloride or polyolefins and has a top surface 13 and a bottom surface 14. The top surface 13 has been treated by having its surface embossed in a certain pattern 15 (called Doeskin) which substantially reduces the noise produced when the top surface 13 of the ASR tape 10 comes into contact with various materials. The bottom surface 14 has been provided with a pressure sensitive adhesive, such that the tape 10 can be installed onto various items, for example a wire harness of an automobile, and remain affixed thereto. Other types of adhesives can be used. 
     Referring now to FIG. 2 which is a photomicrograph showing the surface treatment 15 magnified thirty times, and to FIG. 3 which is a photomicrograph showing the surface treatment 15 magnified sixty three times, the surface treatment 15 shown comprises a pattern of ridges 16, 18 and valleys 17. The ridges are generally of two types, one type of ridge 16 being sinuous or meandering and extending continuously for a length. These extended ridges 16 may have numerous reverse curves. A second type of ridge 18 is generally circular and has an indentation or depression in the upper surface. The valleys 17 surround the ridges 16 and 18 and may be correspondingly sinuous or meandering and extend generally along the length of the extending ridges 16 or may be generally circular and extend around the generally circular ridges 18. The surface treatment 15 is configured such that it covers the entire top surface 13 of the tape 10. The tape is embossed by being fed through a roller which has a surface corresponding to the surface treatment 15 described above. 
     The ASR tape 10 is able to provide the noise reduction characteristics of cloth tape at a significantly reduced cost relative to cloth based tapes. The ASR tape 10 can be easily manufactured in various widths and lengths and, like conventional tapes, can be wound on rolls. The ASR tape 10 can also be customized in terms of unwind, roll size, gauge and color. The ASR tape 10 is durable and should easily last the life of the vehicle that it is installed in, while also providing the temperature and chemical resistance of vinyl based tapes. 
     A number of tests, described below, were done on various prior art tapes having surface treatments such as Smooth finish vinyl tape, Micro finish vinyl tape, and Satin finish vinyl tape all available from Plymouth Rubber Company of Canton, Mass. and Cloth tape available from Kendall Corporation of Lexington, Mass. Three methods of testing the ASR tape 10 against the prior art tapes were performed. The first method, known as the Material Itch Noise Impulse Test for linear sliding (MINIT) measures the sound generated when a test sample of the tape is rubbed against a substrate under a load of 2.5 pounds on a two inch square substrate. The sound produced is measured by the Zwicker method in linear units known as Sones, and the noise ratio versus cloth tape is also in units measured by the Zwicker method in sones (N20 statistics). The results are listed below in table 1. 
     
                       TABLE 1______________________________________                     Noise Ratio vs.Sample Description            Substrate                     Cloth Tape______________________________________Smooth Finish Vinyl Tape            ABS      5.6Micro Finish Vinyl Tape            ABS      3.8Satin Finish Vinyl Tape            ABS      2.2Doeskin ASR Vinyl Tape            ABS      1.8Cloth Tape (Polyken 165)            ABS      1.0______________________________________ 
    
     The sound data has been normalized to cloth tape as 1.0, since cloth tape has been the industry standard for these type of applications. As can be seen from Table 1, the Doeskin ASR tape produces a noise level of 1.8 as compared to the cloth tape. The noise level of the Doeskin ASR tape is below that of the Satin Finish vinyl tape and well below that of the Micro finish vinyl tape and the Smooth finish vinyl tape, while only slightly above the cloth tape. 
     A second method of testing the sound produced by tape is known as the National Technical Systems (NTS) Test Method. This method measures the sound generated when a sample of the tape is vibrated against a substrate under a load of three pounds on a two inch by four inch surface. The sound measured is in decibels (dba). The noise ratio versus cloth tape is as also in dba, and is the ratio average of ten samples. The results from this test are shown below in table 2. 
     
                       TABLE 2______________________________________                     Noise Ratio vs.Sample Description            Substrate                     Cloth Tape______________________________________Smooth Finish Vinyl Tape            ABS      1.17Dull Finish Vinyl Tape            ABS      1.29Doeskin ASR Vinyl Tape            ABS      1.04Cloth (Polyken 165)            ABS      1.0______________________________________ 
    
     This test indicates that the Doeskin ASR vinyl tape produces sound well below the smooth finish vinyl tape and the dull finish vinyl tape, while producing sound only slightly louder than the cloth tape. 
     A third test was done similar to the NTS described above; however in this set of tests, the tape was rubbed against a sample of itself. The results from this test are shown below in table 3 
     
                       TABLE 3______________________________________             Noise Ratio vs.Sample Description             Cloth tape______________________________________Smooth Finish Vinyl Tape             1.15Dull Finish Vinyl Tape             1.19Doeskin ASR Vinyl Tape             0.94Cloth (Polyken 165)             1.0______________________________________ 
    
     Table 3 shows that when the tape sample is rubbed against itself, the noise ratio for the ASR tape is less than the smooth vinyl tape and the dull finish vinyl tape as well as being below the cloth tape. 
     Referring now to FIG. 4, a graph is shown which compares the relative cost of conventional cloth tape, conventional vinyl tape and ASR tape. The cost has been normalized to the cost of cloth tape. Conventional vinyl tape has a relative cost of approximately fifty percent the cost of cloth tape. The ASR tape, while slightly more expensive than the conventional vinyl tape, is still well below the cost of cloth tape, at approximately sixty percent the cost of cloth tape. 
     Having described preferred embodiments of the invention it will now become apparent to those of ordinary skill in the art that other embodiments incorporating these concepts may be used. Accordingly, it is submitted that the invention should not be limited to the described embodiments but rather should be limited only by the spirit and scope of the appended claims.