Device for shutting a sliding door

A device for moving a sliding door laterally, said device comprising:

• a housing including a first end having an air hole formed therein and including a second end having an orifice formed therein, said housing including an inner peripheral surface formed therein and including an inner diameter,
• at least one barrel slidably engaged in said housing and including a first end having a plug secured thereon and slidably engaged in said housing, said barrel including a second end extended outwardly of said housing via said orifice, said plug including an annular groove formed therein so as to define a first side wall arranged closer to said first end of said housing and a second side wall arranged closer to the second end of said housing, said plug including a first end having at least one notch formed in said first side wall and communicating with said annular groove, said plug including an outer diameter slightly less than the inner diameter of said housing,
• a sealing ring engaged in said annular groove, said sealing ring including an outer diameter slightly greater than the inner diameter of said housing for engaging with said inner peripheral surface of said housing, and
• a spring engaged in said housing and said barrel, said spring including a first end secured to said first end of said housing and including a second end secured to said second end of said barrel for biasing said barrel inward of said housing and for allowing said barrel to be pulled outwardly of said housing for extending a length between said first end of said housing and said second end of said barrel,
• said sealing ring being caused to engage with said first side wall so as to allow air to bypass said plug via said notch when said barrel is moved outwardly of said housing, and said sealing ring being caused to engage with said second side wall so as to make an air tight seal between said plug and said housing and so as to force the air to flow out of said housing via said air hole when said barrel is released and is moved inward of said housing by said spring.