Patent Application
20160167466
The invention relates generally to an apparatus for detecting flaws in tires and to an improved probe for a high voltage tire testing system.
As new tires are generally expensive, it is becoming increasingly important to repair damaged tires rather than replace them with new tires, particularly for commercial fleet owners. Repairing a damaged tire is usually very simple and inexpensive, especially repairing simple holes or objects that become embedded in the treaded portion of the tire. However, it is necessary to inspect the tread portion for cracks, fissures, or holes and to repair if necessary.
While visual or machine inspection is reasonably accurate, flaws frequently are missed. The detection rate has been estimated to be on the order of 50%. Missed flaws, during retreading, can create problems in that they allow high pressure air to force its way through the flaws and into the tire structure, causing separation, heat and degradation of the tire, and which in turn can cause a failure of the tire either in the retread shop (“mold blows”) or failure of the tire on the road. Thus an improved machine having greater accuracy is desired.
The invention provides in a first aspect an apparatus for testing a tire, the tire having opposed sidewalls joined together by a crown section, the crown section having an inner surface and an outer surface, the apparatus comprising a support frame, first and second rollers connected to the support frame and arranged to support to support a crown portion of the tire, a probe having a support bracket for receiving a section of chainmail therein, wherein the chainmail is positioned in the tire, wherein the chainmail section is in electrical communication with a first electrode, wherein one of said rollers is a second electrode, and a power supply in electrical communication with the first and second electrode in order to create an electric potential between the first and second electrode.
The invention provides in a second aspect an apparatus for testing a tire, the tire having opposed sidewalls joined together by a crown section, the crown section having an inner surface and an outer surface, the apparatus comprising a support frame, first and second rollers connected to the support frame and arranged to support to support a crown portion of the tire, a probe having a support bracket for receiving a section of chains therein, wherein the section of chains is comprised of a plurality of a first chain member extending in a first direction, wherein each first chain member is in contact with at least one cross chain member, wherein the section of chains is positioned in the tire and in electrical communication with a first electrode, wherein one of said rollers is a second electrode, and a power supply in electrical communication with the first and second electrode in order to create an electric potential between the first and second electrode.
The invention provides in a third aspect an electrode probe useful for testing a tire, the tire having opposed sidewalls joined together by a crown section, the crown section having an inner surface and an outer surface, the apparatus comprising a support frame, first and second rollers connected to the support frame and arranged to support to support a crown portion of the tire, a probe having a support bracket for receiving a section of chainmail therein, wherein the chainmail is positioned in the tire, wherein the chainmail section is in electrical communication with a first electrode, wherein one of said rollers is a second electrode, and a power supply in electrical communication with the first and second electrode in order to create an electric potential between the first and second electrode.
The invention provides in a fourth aspect an electrode probe useful for testing a tire, the tire having opposed sidewalls joined together by a crown section, the crown section having an inner surface and an outer surface, the apparatus comprising a support frame, first and second rollers connected to the support frame and arranged to support to support a crown portion of the tire, a probe having a support bracket for receiving a section of chains therein, wherein the section of chains is positioned in the tire and is in electrical communication with a first electrode, wherein the section of chains is comprised of a plurality of a first chain member extending in a first direction, wherein each first chain member is in contact with at least one cross chain member, wherein one of said rollers is a second electrode, and a power supply in electrical communication with the first and second electrode in order to create an electric potential between the first and second electrode.
The invention will be described by way of example and with reference to the accompanying drawings in which:
The carcass defect testing apparatus 10 comprises a probe 100 having an arm 102 that is connected to a first electrode 110. The first electrode is connected to the control panel or controller system and to a high voltage source. The arm 102 is preferably formed from an insulating material. The first electrode is formed of two conductive plates 120, 130 which are spaced apart and isolated by insulators 122, 124 and 126. A first pair of wire lobes 140,142 are connected to the first conductive plate 120 and are of a sufficient length to engage the inner surface of the carcass in the crown region 128, opposite the tread. A second pair of wire lobes 150,152 are connected to the second conductive plate 130. The second pair of wire lobes 150,152 are positioned to engage the inner sidewalls 131, 133 of the tire and inner crown region 128. The probe 100 further includes a support bar 158 having a chainmail section 160 received therein. The chainmail section extends downwardly from the first electrode 110 and is lowered into engagement with the inner surface of the tire. As shown in
In an alternate embodiment of the invention, the chainmail section may be replace by a section of chains oriented as follows. The section of chains is comprised of a plurality of first chain members, wherein the first chain members extend in a first direction. Preferably, the first chain members are oriented in parallel relation with respect to each other. The first direction is preferably in the vertical direction. The section of chains further includes at least one cross chain member which contacts or interlinks or joins with each first chain member. Preferably, there are at least two cross-chain members. Preferably the cross-chain members are oriented in a ninety degree direction transverse to the direction of the first chain members.
The inventor has found that by replacing the strands of loose chains with the chainmail section that the detection of flaws improved from a rate of detection of approximately 50% with 25% repeatability, to a substantially improved detection rate of 90% with 100% repeatability. The probe 100 and/or the electrode 110 can be used in conjunction with other tire defect testers such as shown in U.S. Pat. No. 6,050,136, U.S. Pat. No. 4,516,068, and U.S. Pat. No. 8,733,160. The disclosures of each of these patents are hereby incorporated by reference.
The first pair of lobed wires 140,142 and the second pair of lobed wires 150,152 and the chainmail section 160 are all electrified when the first electrode is energized. The second electrode is located in the metal roller. When a tire is to be tested, the outer circumference of the tire or tread is positioned on the first and second rollers 40,50 so that a portion of the outer tread surface is in engagement with the first and second rollers 40,50. The probe 100 and the first electrode 110 is positioned inside the tire. The first and second electrodes are connected to a controller system such as described in U.S. Pat. No. 8,733,160. During operation, the tire is rotated by the operator or motor and the first and second electrodes are energized by the controller system. Pulses from the first electrode 110 pass through the tire, to a current sensing module in the controller. If a flaw is present in the tire tread, the insulation provided between the high voltage electrode and the ground will break down, and current will flow. The operator watches or listens for arcing to occur from either of the electrodes 110,50. If arcing occurs, the operator stops rotating the tire and switches off the system. The controller system compares the current generated to the threshold setting. The controller determines if the threshold setting is exceeded, and notifies the operator if the threshold setting is exceeded.
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.
