Abstract: A handle grip comprises an end cap and an elastomeric sleeve. The end cap is retained in the sleeve by projecting legs having barbed enlargements which are to lie between the handle and engage in recesses in the internal surface of the sleeve. The end cap may comprise a separate cover. The sleeve may have axial channels in its inner surface for receiving the legs or barbed enlargements thereon during insertion of the end cap.

Abstract: A valve for a respirator has an elastomeric valve member (18) of generally dished form with an annular channel (25) around its central portion (24). The member (18) is secured at its center by a shouldered conical stem (19) and seals round its periphery (23). The channel (25) allows a sudden collapse of resistance to opening force in the direction of the arrow A above a predetermined amount, but a positive biassing action towards closure. The edges of the channel (26,27) are slightly axially displaced from one another. Both inlet and outlet valves of a respirator may be equipped with such a valve member.

Abstract: A hydraulically damped mounting device has two anchor parts connected by a resilient wall which applies a spring force to relative vibrations of the anchor parts. Also connected to the anchor parts are two bellows walls each defining a corresponding chamber for hydraulic fluid, which chambers are interconnected by a passageway. The bellows walls deform substantially freely of spring resistance and so the volume of the corresponding chamber can change without spring resistance. Thus there is a pumping action of fluid between the chambers, giving a damping action due to the passageway, and hence the spring and damping characteristics of the mount are independently selectable.

Abstract: Air inhaled into a respirator encounters an air guide positioned inside the face-piece of the respirator which acts as a baffle for the air. The passage between the two contains elongate ridges which are shaped to impede and direct the air and to maintain the spacing of the air guide relative to the face-piece. Because of this, the air guide and face-piece can be made symmetrical, with an air inlet canister and a secondary speech outlet module being applied, in either orientation, to laterally symmetrically disposed apertures in the face-piece.

Abstract: A sight-corrective lens is attached between an eyepiece of a respirator and the eye of the wearer by a monocular mount into which the lens fits as if into a standard spectacle frame. Attachment devices for the mount are apertured lugs on a surround of the eyepiece and tabs on the mount. By making the tab and mount in one position of different tangential width from the tab and mount in the other, a desired unique positioning of the lens is assured. The mount may have a seal ring of which the deformable ridge is pretensioned against the eyepiece by the fitting of the tabs in the lugs to prevent ingress of moisture or particles between them.

Abstract: To make a skirt part of a surface-effect vehicle readily and reliably retainable to the vehicle while able to be folded to be sent to the position of use, the skirt part has an enlarged bead to be slid into a restricted-mouth channel on the vehicle, the core of the bead being an elongate spiral spring of stainless steel. End-plugs are fitted to prevent endwards escape from the channel.

Abstract: A hydraulically damped mounting device has two anchor parts, in the form of a sleeve and a tube, connected together by a resilient wall. The resilient wall and the sleeve define a working chamber for hydraulic liquid which is connected to a compensation chamber by a passageway. The passageway may extend directly through the tube or peripherally of the sleeve. The compensation chamber is bounded by a bellows wall, permitting the volume of the compensation chamber to change freely as vibrations of the tube relative to the sleeve change the volume of the working chamber, without the bellows wall being subject to tensile stresses. The sleeve may be formed in two parts which are forced together during manurfacture, enabling a compact construction to be achieved.

Abstract: The pivoted jaws (2,3) of a buckle for a strap (4) are held together by fastening means (22,23) which define a first closed position of the buckle, but which are such as to allow closer approach of the jaws when they squeeze the strap between them. A moment is exerted, if the strap is pulled, between an edge (9) over which it is turned and which is offset from the pivot (10) and this has the effect of causing closer approach of the jaws and thus an increasedly positive hold. Teeth (20) on one of the jaws are of a saw-tooth profile to permit movement of the strap in one direction even when the buckle is closed. Both jaws may be respective one-piece integral plastics mouldings.

Abstract: A hydraulically damped mounting device has two anchor points joined by a resilient spring. The resilient spring and a partition define a working chamber for liquid, the working chamber being in communication with a compensation chamber via a passage. The compensation chamber is bounded by flexible bellows. A flexible diaphragm defines, together with the partition a gas pocket. Relative movement of the anchor points causes a change in pressure in the working chamber. High frequency vibrations are absorbed by movement of the diaphragm with little resistance to movement. Low frequency vibration cause liquid movement through the passage with a strong damping effect. This affect may be controlled by suitable selection of the length and diameter of the passage. Preferably, a bleed orifice extends from the gas pocket to compensate for thermal changes in the volume of the pocket.

Abstract: A strong joint for hoses for the cooling and crankcase ventilation systems of vehicles is made between a hose 1 and a branch by inserting the flared end 3 of a rigid cylindrical insert 4 into a hole 9 in the hose 1 to distort the margin around the hole. A second hose 6 is then positioned over the insert 4 so that its end abuts the margin of the hole and the joint is sealed and secured by an encapsulation which is vulcanized in situ.A curable polymeric liner 5 may be sandwiched between the insert 4 and the spout 6 and also vulcanized to act as a bond.The second hose may be omitted, leaving the insert as a projection to which a second hose may be fitted by other means.

Abstract: To achieve highly fluid-tight sealing of a rigid insert into an orifice in flexible material (101), the insert is made in two parts (103, 106) which can be pressed together with purely axial movement, one part deforming slightly relative to the other at least during the movement, until they adopt as a result of interengagement between them a relationship in which they exert a predetermined sealing pressure on the edge portion of the flexible material between their radially extending flanges (108, 109). A bead (102) may be accommodated in an oversize recess (122) in the flanges. A sub-assembly such as an eyepiece (111) is held fluid tight in one (103) of the parts. Detent means (107, 116) are designed to maintain a sealing contact even if the flexible material (101) or sealing ring (118) creep or set. Though the orifice has an endless edge it is not necessarily circular in outline.

Abstract: A respirator speech transmitter has a projecting tube with a one-way valve at one end and the other end being covered by a baffle having an inner skirt extending around the tube. An outer skirt extends from the tube to surround the inner skirt so that an annular convoluted passageway which increases in annular width as it extends from the tube formed between the outer surface of the tube, the inner skirt and the outer skirt. This convoluted passageway has excellent acoustic properties yet prevents ingress of contaminants. In a modification the valve is at the same end of the tube as the baffle.

Abstract: A piston-cylinder arrangement comprising a cylinder member and piston means mounted slideably therein, the piston means comprising a piston member and a packing member mounted on the piston member for movement therewith, wherein said packing member has first and second axially spaced radially outer surfaces dimensioned such that each contacts slidingly against said cylinder wall and wherein the piston means comprises a lubricant reservoir in communication with the space between said surfaces, which space is substantially closed by said cylinder wall.