| US2928300A | 1960-03-15 | |||
| US2956460A | 1960-10-18 | |||
| US5609715A | 1997-03-11 | |||
| US20030132541A1 | 2003-07-17 | |||
| US20090026834A1 | 2009-01-29 | |||
| US8413692B1 | 2013-04-09 | |||
| US20110207848A1 | 2011-08-25 | |||
| US20090056850A1 | 2009-03-05 |
| CLAIMS: I claim, 1. An apparatus with a means of developing pressure to force sealant from a vessel for injection of said sealant directly into a puncture on a pneumatic tire. 2. The apparatus in Claim 1 where said vessel is a hollow cylinder and said pressure is developed by a piston moving in said cylinder. 3. The apparatus in Claim 2 where said hollow cylinder contains said sealant. 4. The apparatus in Claim 3 where said cylinder has a narrow bore to develop high pressure to force high viscosity sealant through said cylinder into said puncture. 5. The apparatus in Claim 1 where said sealant is elastomeric and cures. 6. The apparatus in Claim 1 where said sealant remains a viscous liquid for a I ong time. 7. The apparatus in Claim 1 where said vessel is made of a material that can be heated to lower the viscosity of said sealant. |
METHOD AND APPARATUS FOR INJECTING SEALANT DIRECTLY INTO TIRE PUNCTURES
CROSS-REFERENCE TO RELATED APPLICATION
Not applicable
BACKGROUND-DESCRIPTION OF PRIOR ART
Bicycles and e-bikes offer some of the best opportunities to reduce C02 emissions and congestion as well as improving public health and quality of life. The thin light weight tires, however, are prone to getting punctured. The time wasted repairing flats on the side of the road is discouraging to many other wise avid cyclists and is the chief drawback to an otherwise highly reliable form of transportation. Many quit cycling altogether.
All the preventative solutions to date such as adding liquid sealants, thorn proofing tires or aftermarket strips result in increasing the mass of the wheel near the rim thereby increasing the moment of inertia of the wheel set. Not only must the rider overcome the translational momentum of the additional weight, the angular momentum must be overcome as well. This results in poor performance accelerating through intersections or knee injuries.
Most common sealants also dry out after a few months requiring that they be scraped out or have more rotational weight added to the tire. Moreover, when the bike is parked overnight with an undetected puncture at top dead center, liquid sealants leak away and the tire must be pumped up again in the morning. Finally, liquid sealants are generally messy.
The traditional solution of carrying a spare replacement inner tube and replacing it on the side of the road is hazardous near heavy traffic, unpleasant in inclement conditions and an inconvenience without a full tool set and work stand. Vulcanizing patches are unreliable when administered in the field and always require removing the wheel, tire and inner tube then reassembly and re-inflation.
SUMMARY
Injecting high viscosity sealant under high pressure directly into the puncture quickly permanently seals the puncture eliminating the above issues.
ADVANTAGES
By injecting sealant directly into punctures, leaks can be repaired in seconds even before the tire loses much pressure allowing for low maintenance low rotational weight wheel sets. Less skill is required than with vulcanizing patches to reliably stop leaks.
DESCRIPTION OF THE DRAWING
Fig. 1 Cross Section of Punctured Tire and Injector
Reference Numbers To the Drawing
11 narrow bore cylinder
13 piston rod
15 spherical piston head
17 high viscosity sealant
19 thumb plate
21 inside of tire
23 typical puncturing object
DETAILED DESCRIPTION
From hydraulics the pressure in a cylinder is the force on the piston divided by the cross sectional area of the cylinder. If the piston-cylinder arrangement has a small enough cross sectional area, a relatively small force on the piston will result in a large pressure, enough to overcome the viscous forces of the sealant as well as the pressure inside of the vehicle tire. Since most punctures are very small in diameter the puncture can be sealed with just a few micro liters of sealant. One thin 10 cm long tube weighing a few grams can easily repair multiple punctures. METHOD
When the cyclist first becomes aware that the tire is punctured, either by loss of air pressure or directly observing the puncturing object or air leaking from the puncture, he stops, rotates the wheel until the puncture is accessible. After any puncturing object is removed the injector is pressed against the rubber surrounding the puncture with enough force to create a seal between the tire and the injector. The sealant is then pumped into the tire and inner tube. If the puncturing object didn't completely penetrate the tire, the sealant will not flow into the tire and is detected by high static back pressure in the injector.