Wheelwright machines – Rubber tire mounting and/or demounting apparatus – For collapsing or shifting tire axially
Reexamination Certificate
2000-05-17
2001-09-18
Smith, James G. (Department: 3723)
Wheelwright machines
Rubber tire mounting and/or demounting apparatus
For collapsing or shifting tire axially
C157S001240
Reexamination Certificate
active
06289962
ABSTRACT:
FIELD OF THE INVENTION
The invention concerns a tire removal apparatus and more specifically an apparatus for pressing a pneumatic tire off a rim of a motor vehicle wheel.
BACKGROUND OF THE INVENTION
A typical tire removal apparatus which operates by pressing a pneumatic tire off the rim of a motor vehicle wheel comprises a pressing blade which is mounted pivotably in a substantially horizontal plane of pivotal movement on a machine frame structure, in particular of a tire fitting and removing machine. The pressing blade is operable to release the pneumatic tire from the rim of the wheel before the tire is totally removed from the wheel. In that procedure, the tire is pressed over the hump of the rim. In such a machine the pressing blade is mounted to the machine frame structure pivotably horizontally in a fixed plane. As rims and pneumatic tires for motor vehicle wheels are of different sizes which are generally between 12 inches and 20 inches, that apparatus suffers from the disadvantage that it is only in rare cases that the pressing blade can be fitted accurately at the same level as the wheel axis. This means that the procedure for pressing the tire off the rim cannot be implemented in the optimum fashion, thereby entailing the risk of damaging the tire, for example by virtue of causing crushing deformation thereof, as well as the rim. Furthermore it is frequently necessary for the pressing blade to be applied to the tire a plurality of times, so that as a result the procedure for pressing the tire off the rim takes up a considerable amount of time.
SUMMARY OF THE INVENTION
An object of the present invention is to provide an apparatus for pressing a pneumatic tire off a motor vehicle wheel rim, which facilitates the procedure involved.
Another object of the present invention is to provide an apparatus for pressing a pneumatic tire off a motor vehicle wheel rim, which while being of a simple structure affords enhanced versatility of operation and operator-friendliness.
Still a further object of the present invention is to provide an apparatus for pressing a pneumatic tire off a motor vehicle wheel rim, which ensures enhanced accuracy of operation and thus more reliable operating results.
In accordance with the invention the foregoing and other objects are attained by an apparatus for pressing a pneumatic tire off the rim of a motor vehicle wheel, comprising a pressing blade mounted pivotably on a machine frame structure, in a substantially horizontal plane of pivotal movement. A lift means is operable to lift the motor vehicle wheel in an upright arrangement with its wheel axis into the plane of pivotal movement in which the tire-removal pressing region of the pressing blade is disposed.
In a preferred feature, the height at which the pressing blade is pivoted in the above-mentioned horizontal plane of pivotal movement with its pressing region which is substantially at the vertical center of the pressing blade, being therefore the level at which the pressing blade is mounted pivotably to the machine frame structure, at least approximately corresponds to the maximum radius of a motor vehicle wheel and is preferably at least approximately between about 50 and 60 cm above the floor surface on which the machine stands.
In another preferred feature the lift means has a wheel support plate which, particularly in the raised position of the lift means, can be locked in a working position so that the raised motor vehicle wheel can be rolled horizontally movably on the wheel support plate. That makes it possible to provide for accurate positioning of the motor vehicle wheel relative to the pressing blade in a horizontal direction, thereby avoiding damage to the wheel rim.
In a further preferred feature the lift means may further have rollers with substantially parallel roller axes, on which the motor vehicle wheel is mounted rotatably about its wheel axis in an upright arrangement on the lift means, when the wheel support plate is lowered. That arrangement provides that the motor vehicle wheel can be turned into the desired position about its wheel axis, for the operation of pressing the tire off the wheel rim.
The lift height can be limited by a setting means which can be pre-adjusted in dependence on the wheel diameter and which can be electrical or mechanical in operation. The pre-settable setting means is also set to the height at which the pressing region of the pressing blade is movable in the horizontal plane over the floor surface. For that purpose, the setting means, which can be of a mechanical nature, can have a scale in a vertical direction, along which a mechanical abutment is displaceable in dependence on the wheel diameter. The vertical scale is calibrated or preset to the height of the plane in which the pressing region of the pressing blade, in particular at the center thereof, is supported pivotably on the machine frame structure.
The setting means may also operate electrically, in which case the height of the horizontal plane of the pressing region of the pressing blade and the respective diameter of the motor vehicle wheel are taken into consideration. The drive for the lift means is then controlled in dependence on the electrical setting means.
Further objects, features and advantages of the invention will be apparent from the description hereinafter of a preferred embodiment.
REFERENCES:
patent: 3782442 (1974-01-01), James
patent: 3905413 (1975-09-01), Myers
patent: 4072178 (1978-02-01), Du Quesne
patent: 4884611 (1989-12-01), Schmidt
Shook Hardy & Bacon L.L.P.
Smith James G.
Snap-on Deutschland Holding GmbH
LandOfFree
Tire removal apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Tire removal apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Tire removal apparatus will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2441656