Abstract: The invention concerns pneumatic actuators for valves comprising a body closed by head flanges, two pistons moving in said body in opposite directions, an output shaft that turns actuated by the pistons, and a stop device on each head flange to limit the stroke of the pistons when they move away from each other towards the head flanges. On at least one side of the actuator body an adjusting device (22) is provided which includes stop means (26, 27) at varying distances from each other in a direction parallel to the movement of the pistons and arranged in a position to intercept and limit the stroke of the pistons when the latter move towards each other.

Abstract: An engine valve actuator for an internal combustion engine is provided. The actuator includes a housing having an opening. An adjustment member is disposed in the housing and defines a fluid chamber having a chamber wall. A piston is also disposed in the opening. The piston defines a piston chamber and has a pressure surface, a protrusion extending from the pressure surface, and a groove disposed in the pressure surface surrounding the protrusion and in fluid communication with the piston chamber. A fluid passageway is adapted to controllably communicate pressurized fluid to the housing opening. A push rod is operatively engageable with the piston and is adapted to controllably actuate an engine valve of the engine.

Abstract: The guide has a barrel segment and a bushing segment. The barrel segment couples to the upper end of the pump barrel. The bushing segment has a bushing stop. The length of the guide is adjustable so as to vary the length of the bushing stop from the barrel. By varying the length of the guide, the travel of the plunger is adjusted to provide for a small compression chamber without the plunger contacting the barrel.

Abstract: An engine valve actuator for an internal combustion engine is provided. The engine valve actuator includes a housing having an opening. An adjustment member is disposed in the housing and defines a chamber. A piston is disposed in the opening of the housing and has a protrusion adapted to be received in the chamber of the adjustment member. The piston has a first position where the protrusion of the piston is disposed in the chamber and a portion of the piston contacts a corresponding portion of the adjustment member and a second position where the portion of the piston is separated from the corresponding portion of the adjustment member. A fluid passageway is adapted to provide pressurized fluid to the opening. The pressurized fluid acts on the piston to move the piston towards the second position to thereby allow pressurized fluid to enter the chamber to prevent the piston from returning to the first position.

Abstract: The invention pertains to a hygienic three way valve for dispensing medicinal, pharmaceutical and food products or other fluid materials which require the processing of fill products without contamination while providing a positive control over the the fill product. The novel hygienic three way valve provides a positive control over fill products by utilizing a fluid activated piston having a positive shut off provided by a substantially cylindrical sealing head in combination with tapered sealing seats that receive the upper and lower sealing surfaces of the substantially cylindrical sealing head. A pneumatic or fluid means is provided for activating the piston and a leak detection port is disposed through the wall of the main valve body communicating with the piston.

Abstract: A positive control fill valve for dispensing fillable materials which eliminates dripping, splashing, sloshing and contamination of fill materials is provided with a fluid activiated fill piston having a substantially cylindrical piston sealing head cooperating with a tapered seat for receiving the piston filling head in combination with a leak detection port for positively detecting potential leaks between the fluid activated fill piston and the product fill chamber. The novel fill valve preferably includes at one end, a pneumatic means for opening and closing the fill valve piston and at the other end, a fill chamber having a tapered seat for positively seating the sealing head of the pneumatically activated piston with a product inlet means disposed therebetween and a two seal arrangement separating the pneumatic chamber at one end from the product dispensing chamber at the other end and a leak detection port disposed intermediate the two seals.

Abstract: First and second pistons are provided in a body, the first piston is restricted by the body and the second piston, and the second piston is restricted by the body and a second piston restricting part. Thus, the first piston can be stopped at three positions, and the respective stop positions can be adjusted. Therefore, when rotation speeds of left and right rotating bodies are switched among three levels by a hydraulic motor, a difference of the number of rotations between the left and right rotating bodies can be eliminated, and a vehicle can be suppressed from deviating from a course while it is going straight. Further, a mounting area of the hydraulic pump can be decreased and a structure can be made simple. The rotation speed of the hydraulic motor is changed among the three levels by a simple structure and simple control without using a complex structure such as a servo valve and complex control.

Abstract: A device for adjusting the central position of the pistons and the angular position of the pinion in a valve driving actuator comprises a tubular body in which are tightly movably arranged a first and second pistons having opposite racks, meshing with a central pinion which can turn through discrete angles. The main feature of the invention is that the inventive device further comprises limit means for limiting the stroke of the pistons toward the pinion, which means can be accessed from the outside of the tubular body.