Self-opening and self-closing slide assembly

A self-opening and self-closing slide assembly comprising:

• a first rail having a side wall, a release portion, a guide groove and a first passage, the release portion located on the side wall and in the first passage, the guide groove located on the side wall and having a longitudinal groove and a transverse groove which communicates with the longitudinal groove;
• a second rail slidably connected to the first rail and having a side wall, a protrusion and a second passage, the protrusion connected to the side wall of the second rail and facing the first passage of the first rail;
• a third rail slidably connected to the second rail and having a push block facing the second passage of the second rail;
• a movable unit having a base, a first resilient member, a push member, a movable member and a second resilient member, the base connected to the side wall of the first rail and having a longitudinal section, a room and a guide passage, the room substantially parallel to the longitudinal section, the guide passage having a longitudinal guide groove and a transverse guide groove which communicates with the longitudinal guide groove, the first resilient member being biased between the base and the push member, the push member located corresponding to the second rail, the movable member movably connected to the base and having a first leg, a second leg, a guide path and an engaging portion, the first leg and the second leg respectively located corresponding to the guide passage and the room of the base, the guide path having a first longitudinal guide path, a second longitudinal guide path and a mediate path, the first and second longitudinal guide paths located on two sides of the engaging portion, the mediate path communicating with the first and second longitudinal guide paths and located corresponding to the engaging portion, the second resilient member located in the room of the base and contacting the second leg of the movable member;
• a passive unit having a link, a connection unit and a first spring, the link having a first protrusion and a second protrusion, the first protrusion located in the guide groove of the first rail, the second protrusion located corresponding to the protrusion of the second rail, the connection unit connected between the movable member and the link, the first spring connected between the link and the connection unit;
• a synchronic unit having a synchronic member and a second spring, the synchronic member pivotably connected to the second rail and having a first contact portion and a second contact portion, the first contact portion facing the side wall of the first rail and located corresponding to the release portion, the second contact portion located corresponding to the push block of the third rail, the second spring connected between the synchronic member and the second rail;
• a hooking unit having a hooking member and a contact member, the hooking member pivotably connected to the third rail and having a hooking portion, the contact member fixed to the third rail and located corresponding to the movable member;
• when the third rail is located at a retracted position relative to the first rail, the second rail is retracted in the first rail, the hooking portion of the hooking member is engaged with the engaging portion of the movable member, the push member is pushed by the second rail and compresses the first resilient member, the first resilient member generates a force in a first direction and the force is applied to the push member, the second leg of the movable member contacts the second resilient member, the push block of the third rail is located corresponding to the second contact portion of the synchronic member;
• wherein, when the third rail is pushed by a pushing force, the hooking portion of the hooking member is disengaged from the engaging portion of the movable member and is moved to the first longitudinal guide path of the movable member, when the pushing force is disappeared, the force in the first direction of the first resilient member is released, the second rail is pushed by the push member and moves relative to the first rail, when the third rail is continuously pulled, the push block of the third rail contacts the second contact portion of the synchronic member so that the second rail is pulled along with movement of the third rail, the protrusion of the second rail pushes the second protrusion of the link so that the first protrusion of the link moves along the longitudinal groove of the guide groove of the first rail, the movable member is moved by the link and the connection unit, the movable member moves along the longitudinal guide groove of the guide passage of the base, when the first protrusion is engaged with the transverse groove of the guide groove, the protrusion of the second rail presses on a top of the second protrusion of the link, the first leg is located in the transverse guide groove of the guide passage and the second resilient member is compressed by the second leg and generates a force in a second direction, when the first contact portion of the synchronic member contacts the release portion of the first rail, the synchronic member swings an angle and the second contact portion of the synchronic member is disengaged from the push block of the third rail, and
• wherein, when the third rail is retracted relative to the first rail, the first contact portion of the synchronic member is separated from the release portion of the first rail and the second contact portion returns to a position located corresponding to the push block, when the contact member pushes the movable member, the movable member is disengaged from the transverse guide groove of the guide passage and the hooking portion of the hooking member contacts the engaging portion of the movable member, the force of the second resilient member retracts the third rail relative to the first rail and the first protrusion of the link is separated from the transverse groove of the guide groove.