Patent Application
20050274448
The invention relates generally to installation of a tire sensor or monitoring system into a tire and, more specifically, to tire surface preparation and apparatus for sensor, tag, or antenna installation.
It is common to employ apparatus, including an antenna, for electronically transmitting tire or wheel identification or other data at radio frequency. The apparatus includes a radio-frequency transponder comprising an integrated circuit chip having data capacity at least sufficient to retain identification information for the tire or wheel. Other data, such as the inflation pressure of the tire or the temperature of the tire or wheel at the transponder location, can be transmitted by the transponder along with the identification data.
It is known in the art to employ an antenna to transmit, at radio frequencies, data from a transponder contained within the structure of a tire or tire and wheel assembly. The antenna comprises a wire or strands of wire and may be formed into a loop and may be an exposed conductor or a conductor sheathed in an extruded covering formed from a suitable material such as plastic. The antenna may comprise an enclosed loop or other known configurations. The antenna and transponder package connected thereto may be affixed to a green tire in a pre-build assembly process or attached to a finished tire in a post-cure operation. While the antenna and transponder may be incorporated into a tire during “pre-cure” manufacture, in practice it is very difficult to do this. Both radial ply and bias ply tires undergo a substantial diametric enlargement during the course of manufacture. Bias ply tires are expanded diametrically when inserted into a curing press, which typically has a bladder that forces the green tire into the toroidal shape of the mold enclosing it. Radial ply tires undergo diametric expansion during the tire building or shaping process and a further diametric expansion during the course of curing. Any antenna and the electronic circuitry associated therewith built into the tire must be able to maintain structural integrity and the mechanical connection between the antenna and transponder package during the diametric enlargement of the tire during its manufacture. Once assembled into the tire, any detected malfunction in the antenna, transponder, or antenna to transponder connection that cannot be repaired destroys the utility of the tire and may necessitate a scrapping of the tire. Hence, placement of an antenna-transponder assembly into a tire during its manufacture carries risk that subsequent failure or breakage of assembly components will necessitate the destruction of the otherwise suitable host tire.
In order to protect the electronics from undergoing the rigors of a tire cure cycle, it has been proposed that the antenna and transponder apparatus be applied by adhesive to a designated tire region in a post-cure operation. However, a positive adhesive application of an antenna and transponder assembly to a tire inner sidewall has proven problematic for a number of reasons. Release agents or other contaminants, present on the designated target region of the tire, can act to weaken or inhibit an adhesive bond between the transponder assembly and the tire. Degradation in the quality of the adhesive bond between the tire and the transponder assembly may result in a separation at some point in the useful life of the tire. Failure of the bond between the transponder assembly and the tire resulting from surface agents, therefore, is a concern with long term implications.
There is, accordingly, a need for ensuring a positive adhesive bond between a tire inner wall and a transponder assembly through the process of targeted tire surface preparation. A suitable method and apparatus for eradicating agents and/or contaminants from a designated target area to the exclusion of other non-targeted areas on a tire inner sidewall is desired. Such a method and apparatus for preparing the targeted tire surface must function in an efficient and, preferable, automated manner. Such a procedure further must be flexible in allowing alternative surface preparation techniques and materials to be utilized if so desired or required. Additionally, any suitable method and apparatus must be both cost effective and reliable and operate with minimal environmental impact.
Pursuant to the invention a method and apparatus for cleaning a tire surface for the purpose of adhering a transponder, sensor, or antenna or other device to the target surface. According to one aspect of the invention, the target surface region of an uncured tire is covered in whole or in part by a thin, flexible membrane prior to the application of the lubricating release agent. The tire is then cured and the film removed, revealing a clean liner surface. Pursuant to another aspect of the invention, an organic or inorganic solvent or surfactant may be used to clean release agents off a target surface of a cured tire. Yet another aspect of the invention utilizes buffing or grinding of the target tire surface to remove the release agent and contaminants from the tire. A solvent may be used in combination with buffing or grinding to remove the ground or brushed material from the surface to prevent such material from being reapplied to the tire. Still a further aspect of the invention utilizes a high-pressure fluid jet to clean release agents from the target tire surface. Another aspect of the invention exposes the target tire surface to a laser beam of sufficient intensity to burn away the surface of rubber containing the release agent. A jet of Flume plasma on the target tire surface may also be employed in another aspect of the invention to enhance the ability of the transponder, sensor, or antenna to adhere to the liner.
The invention will be described by way of example and with reference to the accompanying drawings in which:
A tire pressure monitoring system typically consists of a transponder having one or more sensors. The transponder and associated electronics are housed within a package. In order to send or receive RF signals, a transponder must have an antenna. The antenna is preferably annular in configuration in the subject invention but may have alternative shapes if desired. The transponder and antenna assembly may thus be a loop configuration or may alternatively be configured as a patch to be applied to a tire surface. The antenna and associated transponder, for the reasons discussed previously, is preferably affixed by adhesive or other means to the tire by way of a post manufacture procedure. As used herein, an “annular antenna” may be circular, oblong, symmetrical, or asymmetrical without departing from the subject inventive principles. However, the preferred configuration of the antenna is circular and sized to overlap preferably the tire sidewall region to which it attaches. Other locations such as upper side wall or tire crown area are also possible for assembly location. The antenna may comprise a single wire or a plurality of strands. Various commercially available transponders, sensors, and other electrical devices deployed in combination with an annular antenna formed from conventional conductive materials are suitable for use in conformance with the principles of the subject invention.
Acceptable materials for the antenna wire include steel, aluminum, copper, copper alloys or other electrically conducting wire. As disclosed in this patent document, the wire diameter is not generally considered critical for operation as an antenna for a transponder. For durability, stranded steel wire consisting of multiple strands of fine wire is preferred. Other wire options available include ribbon cable, ribbon conductors on fabric strands, flexible circuits, conductive film, conductive rubber, etc.
Referring initially to
An annular antenna 32 is provided and, in the preferred embodiment, embodies a sinusoidal configuration. Antenna 32 may be alternatively configured into alternative patterns as in a patch or comprise a straight wire(s) if desired and may be filament wire, or cord or stranded wire. Acceptable materials for the wire include steel, aluminum, copper, copper alloys or other electrically conducting wire. As mentioned previously, the wire diameter is not generally considered critical for operation as an antenna and multiple strands of fine wire is preferred. The curvilinear or zigzag form of antenna 32 provides flexibility and minimizes the risk of breakage during manufacture and use explained below.
With continued reference to
In combined reference to
Referring to
It will be appreciated that the subject invention achieves the objectives of providing method and apparatus for cleaning a tire target surface for the adhesion of a product such as a sensor, antenna or ID tag. The techniques herein describe for cleaning the target surface, and other variations obvious to one skilled in the art, can be used as alternative substitutions to avoid different system constraints. For example, some techniques are solvent-less and pose no environmental concerns while some are non-invasive and will not damage or alter the surface of the target tire surface. Others are more cost efficient. A user, accordingly, can select the technique that meets the functional objective of cleaning a target tire surface while also meeting the cost and environmental issues associated with commercial implementation of the cleaning system.
Variations in the present invention are possible in light of the description of it provided herein. While certain representative embodiments and details have been shown for the purpose of illustrating the subject invention, it will be apparent to those skilled in this art that various changes and modifications can be made therein without departing from the scope of the subject invention. It is, therefore, to be understood that changes can be made in the particular embodiments described which will be within the full intended scope of the invention as defined by the following appended claims.
