Patent ID: 7703279
Filing Date: 2010-04-27
Classification: F15B

Abstract:
1. A cylinder for moving a machine element within the cylinder at a first velocity and at a second velocity which is different than the first velocity wherein the machine element has a first side and a second side located opposite to the first side wherein a shaft is attached to the second side of the machine element wherein the shaft moves the machine element within the cylinder, the cylinder comprising: a compartment having a length defined between a first end wall and a second end wall wherein the compartment has a first side wall and a second side wall that connect the first end wall to the second end wall wherein the first side wall and the second side wall are located between the first end wall and the second end wall of the compartment and further wherein the first side wall is located at a distance from the second side wall wherein the first side wall and the second side wall have a first length and the first end wall and the second end wall have a second length wherein the first length is greater than the second length wherein the first end wall, the second end wall, the first side wall and the second side wall define an interior of the compartment wherein the shaft moves the machine element within the interior of the compartment between the first end wall and the second end wall of the compartment at the first velocity; a first light detector adjacent to the interior of the compartment wherein the first light detector detects a first intensity of light within the interior of the compartment wherein the first intensity of the light corresponds to a position of the machine element within the interior of the compartment wherein the first light detector is located at a distance from the first end wall of the compartment; a first base that connects the first light detector to the first side wall wherein the base is located at a distance from the second side wall and further wherein the distance from the first base to the second side wall is greater than the distance from the first side wall to the second side wall and further wherein the distance from the first light detector to the second side wall is greater than the distance from the first side wall to the second side wall; a second light detector adjacent to the interior of the compartment wherein the second light detector is located at a distance from the first end wall of the compartment wherein the distance of the first light detector from the first end wall is different than the distance of the second light detector from the first end wall wherein the second light detector detects a second intensity of light within the interior of the compartment wherein the second intensity of the light corresponds to the position of the machine element within the interior of the compartment; a second base that connects the second light detector to the first side wall wherein the second base is located at a distance from the second side wall and further wherein the distance from the second base to the second side wall is greater than the distance from the first side wall to the second side wall and further wherein the distance from the second light detector to the second side wall is greater than the distance from the first side wall to the second side wall; and a microprocessor electrically connected to the first light detector and the second light detector wherein the microprocessor determines the first velocity of the machine element via the first light detector and the second light detector wherein the first velocity is determined based on the first intensity of light and the second intensity of light.