Coupling for a linear actuator and a sliding valve unit for a sliding gate valve of a molten metal vessel

A sliding gate valve for a molten metal vessel, comprising:

• a slider housing:
• a slider valve unit slidably mounted in said slider housing for movement in a longitudinal direction, said slider unit having a push rod;
• a linear actuator mounting on said slider housing;
• a linear actuator that can be mounted in said linear actuator mounting on said slider housing and that can be removed from said linear actuator mounting on said slider housing, said linear actuator having a drive rod movable in the longitudinal direction when said linear actuator is mounted in said linear actuator mounting on said slider housing;
• and
• a coupling having a structure such that when said linear actuator is mounted in said linear actuator mounting and said drive rod is moved toward said slider valve unit said coupling automatically couples said drive rod with said push rod, and such that when said linear actuator is removed from said linear actuator mounting said coupling automatically uncouples said drive rod from said push rod;
• wherein said coupling comprises:
• a first coupling portion on an end of said push rod;
• a second coupling portion on a front end of said drive rod of said linear actuator;
• wherein one of said first and second coupling portions comprises a central peg having projecting pivotal pawls on both sides thereof and an abutment surface;
• and
• wherein the other of said first and second couplings comprises a sleeve having transverse grooves complementary with and capable of receiving said pivotal pawls of said central peg and a front annular portion, such that when said first and second coupling portions are coupled with each other, said central peg is slid in to said sleeve, said pawls engage said transverse grooves and said front annular portion is located between said pawls and said abutment surface.

A sliding gate valve for a molten metal vessel, comprising:

• a slider housing:
• a slider valve unit slidably mounted in said slider housing for movement in a longitudinal direction, said slider unit having a push rod;
• a linear actuator mounting on said slider housing;
• a linear actuator that can be mounted in said linear actuator mounting on said slider housing and that can be removed from said linear actuator mounting on said slider housing, said linear actuator having a drive rod movable in the longitudinal direction when said linear actuator is mounted in said linear actuator mounting on said slider housing;
• and
• a coupling having a structure such that when said linear actuator is mounted in said linear actuator mounting and said drive rod is moved toward said slider valve unit said coupling automatically couples said drive rod with said push rod, and such that when said linear actuator is removed from said linear actuator mounting said coupling automatically uncouples said drive rod from said push rod;
• wherein said coupling has a structure such that when said linear actuator is mounted in said linear actuator mounting and said drive rod is moved toward said slider valve unit said coupling automatically couples said drive rod with said push rod, and such that when said linear actuator is removed from said linear actuator mounting in a direction transverse to the longitudinal direction said coupling automatically uncouples said drive rod from said push rod.

A coupling arrangement for a sliding gate valve of a molten metal vessel in which a slider housing is mounted below an opening of the molten metal vessel and receives a slider valve unit for opening and closing the opening of the molten metal vessel, the slider valve unit being capable of being slid in a longitudinal direction and having a push rod, and in which a linear actuator is provided for moving the slider valve unit and is adapted to be removably mounted in a linear actuator mounting, said linear actuator comprising a drive rod, and said coupling arrangement comprising:

• a first coupling portion on one of the drive rod and the push rod;
• a second coupling portion on the other of the drive rod and the push rod;
• wherein said first coupling portion comprises a coupling member biased into a coupling position and said second coupling portion is engagable by said coupling member such that when the linear actuator is mounted in the linear actuator mounting, before said first and second coupling portions are coupled with each other, and the drive rod is moved toward the push rod, the first and second coupling portions automatically couple with each other;
• and
• an opening in the linear actuator mounting provided in a direction transverse to the longitudinal direction such that the linear actuator can be removed from the linear actuator mounting in the transverse direction through said opening from a state in which said first and second coupling portions are coupled by having said coupling member and said coupling portion slide relative to each other in the direction transverse to the longitudinal direction until said first and second coupling portions are uncoupled from each other.