CROSS-REFERENCE TO RELATED APPLICATIONS:

This application claims priority of United States Provisional Patent Application Serial No. 61/554,357 entitled "Tire Deflation Apparatus and Method", filed November 1 , 2011.

TECHNICAL FIELD:

The present disclosure is related to the field of apparatuses and methods for use in deflating air-pressurized tires, in particular, large diameter tires used on heavy machinery and mining equipment.

BACKGROUND:

Heavy machinery and equipment used in mining and other like industries often have large diameter tires, some as large as 10 feet in diameter or more, pressurized up to 110 psi or more, as well known to those skilled in the art. When a tire needs servicing, or when the machinery or equipment requires servicing where a tire must be removed first, the tire needs to be deflated before service personnel can perform the service work. If the tire is part of a dual-tire configuration, the tire requiring servicing needs to be deflated to a safe level, such as atmospheric pressure, before work can commence whereas the other tire of the dual configuration also needs to be deflated to a safe level although not all the way to atmospheric pressure. Industry practice dictates that a pressure level of 20 psi in the tire not being worked on in a dual configuration is sufficient to provide a safe environment for service personnel but maintains enough pressure in the tire not being worked on to prevent the bead seal of the tire on the rim from breaking loose, which can add time to the carrying out of the repairs or servicing.

To deflate such large tires, it is known to use a valve core extraction tool that attaches to the valve stem on the tire and permits the removal of the valve core, which is contained in the extraction tool. The extraction tool comprises an exit port that allows the pressurized air in the tire to escape through the exit port when the valve core is removed from the valve stem. The problem with this system is that the time deflate a 10 feet diameter tire having an operation pressure of 110 psi is, on average, 27 minutes or so to a safe pressure before service personnel can work on the tire. It is known that the rate of deflation is a function of the pressure differential between the internal tire pressure and atmospheric pressure. In other words, the rate of deflation is higher when the valve core is removed but as the air pressure in the tire decreases, the rate of deflation of the tire decreases. When the tire is used on mining equipment that generates revenue in the order of $ 0,000.00 per hour, any unnecessary delay in the servicing of the equipment can result in large amounts of lost revenue for the mining operator.

It is, therefore, desirable to provide an apparatus and method for deflating tires that can decrease the deflation time of tires used on heavy machinery and mining equipment. SUMMARY:

A tire deflation apparatus and method is provided. In some embodiments, the apparatus can comprise a venturi tube having a feed tube positioned in the constricted throat of the tube, the feed tube connected to an exit port of a valve core extraction tool, a tool well known to those skilled in the art. In some embodiments, a stream of air can be passed through the constricted throat of the venturi tube wherein a region of low pressure can be formed in the vicinity of the feed tube. When this occurs, a higher-pressure differential can be created between the internal tire pressure and the low- pressure region in the venturi tube, which can also increase the rate at which the tire deflates. In other words, the time to deflate the tire can decrease thereby decreasing the downtime of the equipment or machinery.

For the purposes of this specification and the claims set out herein, the term "air" can comprise atmospheric air, any gas suitable for pressurizing vehicle tires as well known to those skilled in the art, or any combination thereof.

Broadly stated, in some embodiments, an apparatus is provided for use with a valve core extraction tool for deflating an air-pressurized tire, the apparatus comprising: a venturi tube further comprising an inlet, a constricted throat and an outlet; a feed tube having first and second ends, the first end disposed in the constricted throat, the second end configured to operatively couple to an exit port disposed on the valve core extraction tool; and means for operatively coupling the second end to the exit port. Broadly stated, in some embodiments, an apparatus is provided for deflating an air-pressurized tire comprising a valve stem further comprising a valve core disposed therein, the apparatus comprising: a valve core extraction tool configured to operatively attach to the valve stem, the tool further configured to remove the valve core from the valve stem; a venturi tube further comprising an inlet, a constricted throat and an outlet; a feed tube having first and second ends, the first end disposed in the constricted throat, the second end configured to operatively couple to an exit port disposed on the valve core extraction tool; and means for operatively coupling the second end to the exit port.

Broadly stated, in some embodiments, a method is provided for deflating an air-pressurized tire disposed on a wheel rim using a valve core extraction tool, the method comprising the steps of: providing an apparatus, comprising: a venturi tube further comprising an inlet, a constricted throat and an outlet, a feed tube having first and second ends, the first end disposed in the constricted throat, the second end configured to operatively couple to an exit port disposed on the valve core extraction tool, and means for operatively coupling the second end to the exit port; attaching the valve core extraction tool to a valve stem disposed on the rim, the valve stem further comprising a valve core disposed therein; operatively coupling the second end to the exit port; passing a stream of air through the venturi tube from the inlet through the constricted throat to the outlet; and operating the valve core extraction tool to remove the valve core from the valve stem wherein pressurized air disposed in the tire can pass through the exit port and the feed tube to the constricted throat of the venturi tube and exit therefrom via the outlet.

Broadly stated, in some embodiments, a method is provided for deflating an air-pressurized tire disposed on a wheel rim, the method comprising the steps of: providing a valve core extraction tool; providing an apparatus, comprising: a venturi tube further comprising an inlet, a constricted throat and an outlet, a feed tube having first and second ends, the first end disposed in the constricted throat, the second end configured to operatively couple to an exit port disposed on the valve core extraction tool, and means for operatively coupling the second end to the exit port; attaching the valve core extraction tool to a valve stem disposed on the rim, the valve stem further comprising a valve core disposed therein; operatively coupling the second end to the exit port; passing a stream of air through the venturi tube from the inlet through the constricted throat to the outlet; and operating the valve core extraction tool to remove the valve core from the valve stem wherein pressurized air disposed in the tire can pass through the exit port and the feed tube to the constricted throat of the venturi tube and exit therefrom via the outlet.

Broadly stated, in some embodiments, the use of an apparatus in combination with a valve core extraction tool is provided for deflating an air- pressurized tire, the apparatus comprising: a venturi tube further comprising an inlet, a constricted throat and an outlet; a feed tube having first and second ends, the first end disposed in the constricted throat, the second end configured to operatively couple to an exit port disposed on the valve core extraction tool; and means for operatively coupling the second end to the exit port. Broadly stated, in some embodiments, the use of an apparatus is provided for deflating an air-pressurized tire comprising a valve stem further comprising a valve core disposed therein, the apparatus comprising: a valve core extraction tool configured to operatively attach to the valve stem, the tool further configured to remove the valve core from the valve stem; a venturi tube further comprising an inlet, a constricted throat and an outlet; a feed tube having first and second ends, the first end disposed in the constricted throat, the second end configured to operatively couple to an exit port disposed on the valve core extraction tool; and means for operatively coupling the second end to the exit port.

Broadly stated, in some embodiments, the apparatus can further comprise a first hose configured to operatively couple the second end to the exit port.

Broadly stated, in some embodiments, the apparatus can further comprise means for coupling the inlet to a source of compressed air.

Broadly stated, in some embodiments, the coupling means can further comprise a second hose configured to operatively couple the inlet to the source of compressed air.

Broadly stated, in some embodiments, the source of compressed air can further comprise an air compressor. Broadly stated, in some embodiments, the apparatus can further comprise an air pressure control system disposed between the feed tube and the coupling means.

BRIEF DESCRIPTION OF THE DRAWINGS: Figure 1 is a block diagram depicting one embodiment of a tire deflation apparatus.

Figure 2 is a block diagram depicting another embodiment of the apparatus of Figure 1.

DETAILED DESCRIPTION OF EMBODIMENTS: Referring to Figure 1 , one embodiment of apparatus 10 to deflate a tire is shown. In some embodiments, apparatus 10 can comprise venturi tube 12, further comprising one end of feed tube 14 disposed in constricted throat 32 of tube 12, wherein the other end of feed tube 14 can be configured to be connected to exit port 19 of valve core extraction tool 18 upon which, communication can be established between exit port 19 and throat 32. In some embodiments, hose 16 can be used to connect exit port 19 to feed tube 14. In some embodiments, apparatus 10 can comprise means for establishing a flow or stream of air through venturi tube 12. In some embodiments, the means can comprise hose 28 connecting a source of compressed air, such as from an air compressor (not shown) to inlet 30 of venturi tube 12. When extraction tool 18 is attached to valve stem 26 disposed on rim 22 of wheel 20, wherein tire 24 can be disposed thereon, and when hose 16 connects exit port 19 to feed tube 14, extraction tool 18 can be used to remove the valve core from valve stem 26. In so doing, pressurized air in tire 24 can exit through exit port 19 and pass through hose 16 and feed tube 14 into throat 32 of venturi tube 12. As compressed air from the compressor enters venturi tube 12 through inlet 30 via hose 28, a low pressure region can be created in throat 32 thereby resulting a pressure differential, as between the air pressure in tire 24 and throat 32, that can be greater than the pressure differential between the air pressure in tire 24 and atmospheric pressure.

In some embodiments, a method to deflate a tire can comprise the following steps. Extraction tool 18 can be attached to valve stem 26. Exit port 19 can be connected to feed tube 14. In some embodiments, hose 16 can be used to connect exit port 19 to feed tube 14. A stream of air can be passed through venturi tube 12 to create a region of low pressure in the vicinity of feed tube 14 disposed in constricted throat 32 before the air exits venturi tube 12 via outlet 34. In some embodiments, the stream of air can be provided from an air compressor (not shown) operatively connected to inlet 30 via hose 28. Extraction tool 18 can then be operated to remove the valve core from valve stem 26 to allow the pressurized air in tire 24 to pass through exit port 19 to throat 32 of venturi tube 12 via hose 16 and feed tube 14. As the pressure in throat 32 can be lower than atmospheric pressure, the rate of deflation of tire 24 can be greater than if exit port 19 is left unconnected thereby allowing pressurized air tire 24 to escape to the atmosphere.

Referring to Figure 2, another embodiment of apparatus 10 is shown. In this embodiment, apparatus 10 can further comprise air pressure control system 35. In some embodiments, system 35 can comprise air valve 36, as well known to those skilled in the art, disposed between hose 16 and feed tube 14. In further embodiments, valve 36 can comprise an electrical solenoid control mechanism to open and close valve 36. In some embodiments, valve 36 can be configured as a normally open valve, although it can be configured as a normally closed valve in other embodiments. In some embodiments, system 35 can further comprise pressure switch 38, as well known to those skilled in the art, operatively connected to valve 36 via control wires 40 wherein pressure switch 38 is operatively connected to line 16 via tee-line 17 to provide communication to pressurized air disposed in line 16. System 35 can further comprise activator switch 42 operatively connected to pressure switch 38 via control wires 44. In some embodiments, when system 35 is installed in apparatus 10, activator switch 42 can be used to operate apparatus 10 to start the deflation of a tire. In other embodiments, activator switch 42 can be used to simply activate pressure switch 38. In some embodiments, pressure switch 38 can monitor the air pressure in hose 16, and when the air pressure in hose 16 reaches a predetermined pressure, as set and/or configured on pressure switch 38, pressure switch 38 can then operate valve 36 to close. In operation, system 35 can be configured, in some embodiments, to enable apparatus 10 to deflate a tire to a predetermined air pressure, and then automatically stop the deflation process to prevent further depressurization of the tire. This can be useful in deflating one tire in a dual-tire configuration to a safe pressure, such as 20 psi, to allow service personnel to work on the other tire in the dual-tire configuration, as noted earlier in this specification. In some embodiments, apparatus 10 can be used to deflate the tire without service personnel having the monitor the pressure during the deflation process; apparatus 10 can be left unattended to deflate a tire until the air pressure in the tire reaches the predetermined air pressure as set or configured on pressure switch 38.

Although a few embodiments have been shown and described, it will be appreciated by those skilled in the art that various changes and modifications might be made without departing from the scope of the invention. The terms and expressions used in the preceding specification have been used herein as terms of description and not of limitation, and there is no intention in the use of such terms and expressions of excluding equivalents of the features shown and described or portions thereof, it being recognized that the invention is defined and limited only by the claims that follow.