Hydraulic shock absorber

Abstract

A piston is slidably fitted in a cylinder for dividing the interior of the cylinder into upper and lower cylinder chambers. The upper cylinder chamber communicates with the lower cylinder chamber through a check valve. The lower cylinder chamber communicates with a reservoir through a check valve. The upper cylinder chamber communicates with the lower cylinder chamber through an extending side damping valve. The lower cylinder chamber communicates with the reservoir through a contracting side damping valve. A piston rod is connected to the piston. When the piston rod is in an extending stroke, a damping force is generated by the extending side damping valve. When the piston rod is in a compressing stroke, a damping force is generated by the contracting side damping valve. The reservoir includes a connecting hole having an opening. A baffle plate is provided within the reservoir and above the opening of the connecting hole. Arrangement of the baffle plate above the opening of the connecting hole defines an entrance portion through which hydraulic fluid flows from the connecting hole to the reservoir. The cross sectional flow area of the entrance portion is gradually expanded, thereby decreasing the flow velocity of the hydraulic fluid to restrain generation of eddies to prevent cavitation and aeration.