US 3,963,045 AGranted

Cushion control accessory for pneumatic or hydraulic cylinders

OwnerVernon Damitzinventor

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Abstract

A control apparatus for use with cylinder assemblies for cushioning the piston as it reaches the end of its stroke so as to control the speed at which the piston approaches the cylinder ends and to prevent damage to the cylinder assembly. The control apparatus includes a body which has an inlet port that is adapted for connection to the cylinder assembly and an outlet port that is aligned with the inlet port and is adapted to vent to atmosphere or for line connection. An expansion chamber is provided within the body and includes a valve for controllably venting the chamber. A first passageway connects the inlet port, outlet port and expansion chamber, and a second passageway connects the inlet port and the first passageway for controlling flow between the inlet port and expansion chamber. A spool-type valve element is provided which moves within the first passageway and controllably opens and closes the inlet port in response to the pressure in said expansion chamber so as to create the cushion in the cylinder. The air pressure in the chamber slowly vents through the valve means in the expansion chamber so as to permit controlled seating of the piston in the cylinder.

Claims7

Dependent claims

A cushion control apparatus, for use with a pneumatic cylinder assembly which has a cylinder and a piston, for cushioning the piston as said piston reaches the end of its stroke and for preventing damage to the cylinder assembly, which comprises:

a. a body having:
an inlet port on one side of the body which is adapted to receive air flow from a cylinder;
an outlet port;
expansion chamber means within said body;
first branched passageway means within said body interconnecting said inlet port, outlet port and said expansion chamber means;
and second passageway means connecting said inlet port and a branch of said first passageway means for cooperating in directing air flow from said inlet port to said chamber means;
b. pressure responsive valve element means for cooperation in directing air flow from said inlet port through said second passageway to said chamber means and for controllably opening said inlet port and closing said inlet port in response to increased pressure in said chamber means so as to cushion said piston, said valve element means being mounted in said first passageway for reciprocal movement therein and said valve element means being generally cylindrical in shape and including land portion means cooperating with said body which means are arranged for providing communication between said second passageway and said expansion chamber means;
c. valve means associated with said chamber means for venting said chamber means to atmosphere so as to controllably release said cushion;
and
d. control valve means are provided in association with said second passageway for cooperating in controlling the flow of air from said inlet port to said expansion chamber means.

7 more elements

A control apparatus for use with a pneumatic cylinder assembly having a cylinder and a piston to cushion the piston at the end of the stroke and minimize damage to the cylinder assembly, said control apparatus comprising:

a. a body having:
i. means defining an accumulator chamber therein,
ii. means defining a primary air flow passageway having:
an inlet port at one end for connection to a cylinder assembly and an outlet port opening to atmosphere,
iii. means defining a valve element receiving passageway for interconnecting said chamber and said primary air flow passageway,
iv. means defining a chamber inlet passageway for directing flow from said primary passageway, at a position upstream of said inlet port and downstream of said valve element receiving passageway, to said chamber,
v. means defining a vent passageway for venting said chamber to atmosphere.
b. chamber inlet valve means operatively associated with said inlet passageway for controlling flow through said inlet passageway means,
c. vent valve means operatively associated with said vent passageway for controlling flow from said chamber through said vent passageway, and
d. pressure responsive valve element means operatively associated with said valve element receiving passageway means for controlling flow through said primary passageway means in relation to the difference in pressure between said chamber and said primary passageway means, said valve element means being mounted for reciprocal movement between an open position and a closed position, and a secondary passageway associated with said valve element means and opening in response to movement thereof for communicating the primary passageway with said chamber.

7 more elements

Dependencies are inferred from the claim text.