Abstract: The invention relates to a pressure-regulating valve with slide valve, comprising three decreasingly pressurized enclosures: an admission chamber, a discharge chamber and a return chamber. Said valve comprises means for creating a communication, in the intermediate position of the slide valve, between the discharge chamber and the return chamber, which means constitute a restriction whose dimensions are selected so that the fluid flowing therethrough is equal to the maximum value of the flow of fluid between the admission chamber and the discharge chamber. The present invention finds an application in the production of a stable hydraulic handling machine.

Abstract: To enable a tractor bonnet to be opened and closed it is pivotably connected near its front end to longer arms of respective laterally-spaced interconnected bell-crank levers which are pivotably mounted about a common transverse axis on an upstanding sub-frame secured to the tractor's main frame. When the bonnet has been initially moved forwardly, thus pivoting the levers relative to both the bonnet and the sub-frame, the shorter arms of the levers abut against the sub-frame whereafter the rear end of the bonnet is secondarily moved upwardly and forwardly into opened position by pivoting the bonnet relative to the stationary levers. The bonnet is closed by performing the same movements in reverse sequence, a transverse arch preferably being so fixed relative to the main frame as to guide the bonnet near the end of its initial closing movement.