Abstract: In a vehicle transmission where there are two ranges of gear ratios, changing between the ratios is achieved by means of a burst of compressed air triggered by depression of the clutch, which compressed air is used to set a valve in a compressed air line to an open or a closed position in dependence upon the position of a range pre-select control. When the valve is open one range is selected. When closed, the other range is produced.

Abstract: A pneumatic tire of braced tread construction has a tread width which is less than its bead width. The sidewalls of the tire each have a flex area located nearer to the tire tread than to the tire bead, which flex area is adapted to exhibit relatively greater flexibility than surrounding areas of the sidewall. The tire is adapted to have a run-flat capability, being of radial ply construction for increased sidewall flexibility, and, when mounted on a wheel, incorporating a lubricant to lubricate areas of contact between the bead and tread regions of the tire when the tire is flat.

Abstract: A hand and guard rail system has a clamp member made up of two identical elements which have semi-circular sectional portions at right angles to one another. The elements co-operate in clamping so that each portion forms a tubular portion to locate a pair of tubular rail members at right angles to each other.

Abstract: A method of, and apparatus for, retarding a vehicle equipped with an epicyclic gearbox in which a reverse gear train is included. In normal operation to engage reverse gear the reverse gear train contains a reaction member which is clamped to reverse the direction of rotation of the gearbox output shaft. To provide for retardation the reverse gear reaction member is not clamped but the clamping means is operated to allow slipping or intermittent operation of the reverse gear train so providing a retarded but not reversed operation of the output shaft.

Abstract: A ferrous-based component is nitrided by subjecting the heated component to an atmosphere of ammonia and then to an atmosphere of an inert gas. The undesirable nitrogen-rich layer which was hitherto produced at the surface of the component in nitriding is reduced or eliminated in the process of the invention.

Abstract: A fluidizing tank for granular refractory material has a porous bottom wall that is displaceable downwardly from a bottom edge of the tank in order to define a gap through which contaminating precipitated particles can fall from the tank, preferably aided by a downward slope of the porous wall. A receptacle housing the tank contains a vibratory sieve for separating the particles from the material falling from the tank so that the sieved material may be returned to the tank, preferably directly by mechanical or suction transfer from the bottom of the receptacle.

Abstract: A truck cab has a panel which extends across the front of the cab immediately below a windscreen for the cab, there being a gap between the top edge of said panel and the main body of the cab, the top edge being so shaped that it acts as a grab rail or handle by which a person can pull themselves up.

Abstract: Two or more carburetors for an internal combustion engine are mounted on a member providing inlet ducts for each carburetor to engine. The member also includes: An engine coolant duct to heat the ducts; and, further an exhaust gas duct to provide rapid heat-up of the inlet ducts on cold starting. A recirculating exhaust gas valve can also be used.

Abstract: A truck having a cab of the tilting variety includes an enclosure for the engine which enclosure is in two parts, the first part carried by the chassis and the second part carried by the cab so that when the cab is tilted the enclosure is opened for access to the engine.

Abstract: A spark ignition engine has a crankshaft speed pulse generator and a plurality of cylinders each cylinder containing a spark plug. Each plug is connectable to a high voltage ignition winding by way of a reed relay. The relays are divided into two groups and, with a periodicity dependent on generator output, a selected relay in each group is closed immediately prior to generation of voltage in the winding and opened when the voltage has been dissipated. Although both plugs connected to the selected relays produce a spark only one of the cylinders contains fuel mixture and, consequently, one one power stroke occurs.

Abstract: Resistance welding apparatus having a power driven welding head carrying a first welding electrode for co-operation with a second welding electrode, wherein the head is switched from a low-force approach operating mode to a high-force squeeze operating mode only when the welding electrodes electrically contact one another, either directly or through a workpiece therebetween, so that no gap exists in which an operator's hand or finger can be crushed between the electrodes upon transition from low-force to high-force operation.

Abstract: A ladder type chassis for a truck is made up of two sub-frames, each comprising two parallel channel-sectioned members interconnected by cross-members, the channel-sectioned members of the first sub-frame facing outwardly to form a wider engine bay than would be the case with conventional inward facing channel-sectioned chassis members.

Abstract: A truck tractor has the fifth wheel mounted on a sub-frame which is pivotally connected between the tractor chassis and the rear axle of the tractor in order to improve the ride and handling of the tractor both when the truck is laden and unladen. Suspension elements are connected between the rear axle and the chassis frame. In one embodiment of the device the suspension elements comprise rubber blocks, and in another embodiment of the device, the suspension elements comprise leaf springs.

Abstract: A vehicle steering wheel has the wheel rim connected to the hub by a dished metallic member that has a plurality of slots extending in spaced overlapping relationship around the dished member. The slotted dished member is relatively strong when steering effort is applied but in the event of driver impact is relatively easily tiltable to spread the impact load on the driver's chest and is then collapsible to absorb substantial impact energy.

Abstract: A Vehicle has energy absorbing means for reducing the severity of occupant injury in an accident comprising a moulding of rigid plastics foam covered with a layer of semi-rigid plastics foam. The rear face of the moulding is formed with a plurality of integral projections which are arranged to collapse, and thereby absorb energy, on occupant impact. The projections may comprise rib-like walls defining a series of discrete cavities, may comprise columns extending to the rear face of the moulding.

Abstract: A coach or bus of integral construction made up of a lower section, housing engine, suspension and service units and ducts, and an upper section incorporating a passenger saloon. The lower section comprises a sequence of boxes serving simultaneously as structural members and running component enclosures. The box walls are of readily replaceable flat panels. The combination of the upper and lower sections provides a much stiffer structure than heretofore found in conventional constructions.

Abstract: An elastomeric glazing strip for dry-mounting a window pane in a frame, the bottom of the channel in the strip for receiving the glass being formed by a web which resiliently flexes into an interior space of the strip for accommodating manufacturing tolerances in the dimensions of the glass and frame.

Abstract: A poppet valve assembly for an internal combustion engine, in which a tappet foot is in screw thread engagement with the end of a valve stem; a retainer collar non-rotatably engages both the valve stem and the tapper foot; and a valve return spring acting on the retainer collar must be compressed in order to disengage the collar from the foot for adjustment of the valve operating clearance.