Casement window opening control device with sliding arms

A casement window restrictor comprising:

• a bracket adapted for attachment to a pivotable window sash;
• a first arm having a first end and a second end, said first end pivotally coupled to said bracket;
• an elongated second arm having a first end and a second end, at least a portion proximate to said first end of said second arm slides longitudinally while coupled to a portion of said first arm;
• means for biasing said second end of said first arm into a first arm position;
• a base member adapted for attachment to a master window frame of a casement window;
• said base member comprising a through-opening;
• a hook received in said through-opening of said base member and configured to pivot therein from a first hook position to a second hook position;
• a portion of said hook in said first hook position configured for engagement within an opening in said second end of said second arm, with said first arm in said first arm position and the window sash in a closed position, and configured for disengagement from the opening in said second end of said second arm when said hook is pivoted into said second hook position;
• and
• a safety button configured to prevent said pivoting of said hook into said second hook position when in a first safety button position and to permit said hook to pivot when in a second safety button position;
• and
• wherein said first arm position of said first arm comprises a substantially upright position.

A device, for selectively restricting an amount of pivotal travel of a window sash hingedly coupled to a master window frame and configured to rotate into an open position from a closed position, said device comprising:

• a bracket adapted for attachment to the window sash;
• a first arm having a first end and a second end, said first end pivotally coupled to said bracket;
• a second arm having a first end and a second end, at least a portion proximate to said first end of said second arm slidably coupled to said first arm;
• said second end of said second arm comprising an opening;
• biasing means for positioning said first and second arms into a first position;
• a base member adapted for attachment to the master window frame;
• said base member comprising a through-opening;
• a hook received in said through-opening of said base member and configured to pivot therein from a first hook position to a second hook position;
• a portion of said hook in said first hook position configured for engagement with said opening in said second end of said second arm when the window sash is moved into the closed position with said first arm in said first position;
• and said portion of said hook configured for disengagement from said second arm when said hook is pivoted into said second hook position;
• a safety button configured to prevent said pivoting of said hook into said second hook position when in a first safety button position, and to permit said hook to pivot when in a second safety button position;
• wherein said first position of said first arm comprises a substantially upright position;
• and
• a spring configured to bias said safety button into said first safety button position and bias said hook into said first hook position.