Abstract: The present invention is directed to an actuator piston assembly for use in a rocker arm system. The actuator piston assembly is capable of actuating at least one engine valve during for example engine braking. The actuator piston assembly includes a piston body having a hollow interior, a screw assembly received within the hollow interior of the screw assembly, a biasing assembly for biasing the piston body with respect to the screw assembly, a cap assembly located within the hollow interior, wherein the biasing assembly interacts with the cap assembly and the screw assembly, and a securing assembly for movably securing the piston body to the screw assembly.

Abstract: In engine brakes of the type in which a master piston is reciprocated by an associated internal combustion engine part to hydraulically pressurize hydraulic fluid in a plenum, after which a trigger valve is opened to apply that hydraulic pressure to a slave piston which opens an exhaust valve in the engine to produce a compression release event, an electronically controlled trigger valve is used in place of the conventional mechanically operated trigger valve. The electronically controlled trigger valve can be much simpler and cheaper than the mechanical trigger valve it replaces, and it can also be readily controlled to automatically vary the timing of the compression release events if desired.

Abstract: A clip valve for limiting the stroke of an exhaust-valve-operating hydraulic actuator piston in a compression release engine brake has a plunger which follows the actuator piston down until the motion of the plunger is stopped by a retaining ring in a bore in which the plunger reciprocates. When the plunger is thus stopped, an aperture in the slave piston is uncovered, thereby allowing pressurized hydraulic fluid to escape from the actuator piston cylinder and preventing further downward motion of the actuator piston. The clip valve apparatus is constructed to facilitate assembly of the plunger and retaining ring in the bore, as well as to provide secure and fail-safe retention of those components in the bore. The parts of the clip valve are simplified and preferably also reduced in number as compared to the prior art.

Abstract: In an internal combustion engine equipped with a turbocharger and a compression release engine brake, excessive stress in the engine and engine brake during operation of the engine brake at relatively high engine speeds is prevented by limiting the intake manifold pressure increase produced by the turbocharger, particularly at higher engine speeds. When the engine brake is turned on, a pressure sensor is enabled to sense the gas pressure in the intake manifold. When the pressure sensor detects that the intake manifold pressure is above a predetermined threshold level, the pressure sensor applies gas from the intake manifold to a pneumatic actuator. The pneumatic actuator opens a pressure relief valve which releases gas from the intake manifold to the ambient atmosphere.

Abstract: In a compression release engine braking system for a turbocharged internal combustion engine, excessive stress associated with opening the exhaust valves of the engine near top dead center of engine compression strokes when the engine is turning at high speed is prevented by reducing the intake manifold pressure from what it otherwise would be at that high speed. This is done by retarding the turbocharger so that its speed is less than it otherwise would be at high engine speed. Turbocharger retarding can be accomplished in any of several ways such as by restricting the flow of engine exhaust gas to or from the turbocharger, or by allowing a portion of the exhaust gas to bypass the turbocharger.

Abstract: Two members which initially have a very loose, complementary dovetail relationship to one another are firmly secured together by causing the material of a ductile locking member to flow into the space which initially exists between the complementary dovetail shapes. This technique is especially suitable for joining materials which are otherwise difficult to unite. For example, this technique can be used to secure an insert of tungsten carbide or ceramic in a main member of steel. Wear or bearing inserts of hard material can be secured in this way to the hydraulic pistons (especially the master pistons) used in compression release engine brakes.

Abstract: In a compression release engine brake, the starting point for the forward stroke of the slave piston is automatically adjusted when the engine brake is turned on, e.g., to remove the clearance which is typically provided between the slave piston and the associated internal combustion engine exhaust valve mechanism. Two elements in the engine brake move apart during the first forward stroke of the slave piston. Hydraulic fluid enters a chamber formed between these two members and is tarpped there when the returning slave piston closes the aperture through which the fluid entered that chamber. The return strokes of the slave piston are thus foreshortened. The closing of the above-mentioned aperture by the slave piston constitutes the sole means by which hydraulic fluid is trapped in the chamber. No other check valve element is required.

Abstract: Hydro-mechanical brake timing means are provided to control the timing of an engine braking system of the gas compression type for an internal combustion engine wherein the engine braking system includes a hydro-mechanical mechanism which opens the exhaust valve near the top of the compression stroke of the engine so that the energy absorbed by the engine during the compression stroke is not returned to the engine during the expansion stroke. In accordance with the present invention, hydro-mechanical means are provided in the exhaust valve actuating mechanism whereby the clearance in that mechanism is reduced to a value which maximizes the retarding power developed by the engine whenever the engine brake is activated.

Abstract: An improved solenoid adapted for use in a solenoid actuated valve or switch is disclosed. Increased speed of operation and increased capacity result from the incorporation of a plate or disc type of armature which is relatively unrestrained with respect to the actuating mechanism for the valve or switch device to be operated thereby, whereby the effective air gap in the magnetic circuit may be substantially reduced.