Connecting device for modular frame construction

A releasable joint for modular frame construction comprising a first elongated frame member and a second frame member and a connection device for releasably securing the two frame members together,

• the first frame member having a T-shape slot extending longitudinally of the first frame member and defined by a channel opening at an external face of the first frame member of a constant width and by an inner chamber inward of the channel wider than the channel and defining internal chamber shoulder surfaces on each side of the channel,
• the second frame member having an external end face with a central slide bore extending into the second frame member open at the end face,
• the connection device including a hook member and a spring;
• the hook member being elongated about an axis and having a slide portion on an inner end and a hook portion on an outer end, the hook portion having a head at the outer end of the hook member joined by a shank to a remainder of the hook member,
• the head as seen in a first longitudinal side view having a first width normal the axis of the hook member which is wider than a width of the shank in the first longitudinal side view so that the head presents head shoulder surfaces directed axially towards the inner end of the hook member,
• the head as seen in a second longitudinal side view having a second width normal the axis of the hook member which is less than the first width of the head,
• the first longitudinal side view and the second longitudinal side view are disposed relative to each other at a displacement angle about the axis of the hook member as seen in axial end view,
• the slide portion of the hook member longitudinally slidably received within the slide bore with the hook member rotatable about its axis relative the second frame member,
• the spring coupled between the second frame member and the hook member biasing the hook member longitudinally out of the slide bore and biasing the hook member to rotate in one direction about its axis relative the second frame member,
• a camming recess in the slide portion opening radially of the axis and presenting a camming surface therein,
• the second frame having an actuator bore extending transverse to the slide bore from an outer open end into the slide bore,
• an actuator member displaceable within the actuator bore between an outer position and an inner position,
• the actuator member having a camming protuberance at its inner end for engaging the camming surface,
• the camming protuberance extending into the recess so that engagement between the camming surface and the camming protrusion prevents withdrawal of the hook member from the casing member and the spring biases the hook member to urge the camming surface into engagement with the camming protuberance which engagement determines the position of the hook member relative the casing member both axially and rotationally;
• in moving the actuator member from the outer position towards the inner position, the camming protuberance cams on the camming surface against the bias of the spring to both draw the hook member axially inwardly into the casing member and rotate the hook member relative the casing member through the displacement angle,
• the first width of the head being greater than the width of the channel,
• the second width of the head being less than the width of the channel,
• with the end face of the second frame member engaging the external face of the first frame member with the slide bore centered on the channel in an unlocked position, the actuator is in its outer position and the hook portion is in a rotational position which presents the second width of the head disposed so that the hook portion passes through the channel and the hook portion extends from the slide bore sufficiently that the head shoulder surfaces of the hook portion are in the inner chamber inward of the chamber shoulder surfaces and from which unlocked position on movement of the actuator member to the inner position, the hook portion is rotated through said displacement angle to a position which presents the first width of the head disposed so that the head does not pass through the channel and the hook member is drawn axially into the slide bore to engage the head shoulder surfaces with the chamber shoulder surfaces drawing the external face of the first frame member into a frictional engagement with the end face of the second frame member.

A device for connecting a first and a second elongated frame members in a perpendicular relationship relative to each other, said device comprising:

• (a) a first connecting member being transversely housed within said first frame member at one end thereof and having a transverse bore;
• (b) a second connecting member being housed within a longitudinal central bore of said first frame member at said one end thereof and being slidably and rotatably received within said transverse bore of said first connecting member;
• (c) a rotatable locking head being attached to an end of said second connecting member which extends outwardly from said one end of said first frame member, said locking head being adapted to rotate and engage within an elongated groove formed along one side of said second frame member;
• (d) a spring for biasing axial and rotating movement of said second connecting member relative to said first connecting member, and
• (e) a set screw threadably received in said first connecting member and having a conical tip for urging against a conical shaped recess provided on said spring biased second connecting member which is adapted to slide and rotate between an off-center position where said conical tip is off-center relative to a center of said conical shaped recess and a center position where said conical tip is at the center of said conical shaped recess;
• (f) whereby turning said set screw in one direction urges said spring biased second connecting member to slide and rotate axially within said transverse bore towards one direction until said rotatable locking head tightly engaged with said second frame member thereby connecting and locking said first and second frame members, and turning said set screw in the other direction urges said spring biased second connecting member to slide and rotate axially within said transverse bore towards an opposite direction until said rotatable locking head disengaged from said second frame member thereby disconnecting said first and second frame members.