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Heavy-duty tyre changer
Page 94
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An electro-hydraulic tyre changer for the removal and refit of heavy-duty, commercial and industrial tyres quickly—even those that are stuck to the rim —has been announced by Harvey Frost and Co Ltd. The changer is known as the Presto and is said to be the first of its type to be manufactured in Britain; it will handle tyres on flat-base rims up to a maximum wheel diameter of 4ft Bin. (1430mm).
The tyre changer consists of a strong metal frame from which are suspended four pressure feet, adjustable laterally by an hydraulic ram, the base of the frame being fitted with an hydraulic vertical thrust ram. Both rams are actuated by an electrically operated pump and controlled by two levers mounted at the side of the frame.
. The wheel assembly is loaded on to the press table via a built-in roller conveyor and located over the head plate of the vertical ram, while the upper ram positions the pressure feet so as to meet the tyre bead when the lower ram is raised.
Hydraulic pressure then forces the tyre down clear of the locking ring permitting its easy removal. With the wheel reversed, further pressure of the vertical ram completely removes the tyre from the rim.
Made by: Harvey Frost and Co Ltd, Dunmow Road, Bishop's Stortford, Herts.