A temperature activated door spring device includes a spring having a coil with a contiguous upper arm and lower arm. The coil includes an inner hinge pin hole and has a circumferential edge sized to mount on the top of a hinge knuckle. A collar is affixed within the inner hinge pin hole wherein the inner hinge pin hole is encompassed by the collar sized to accept an inserted hinge pin. A pellet hole is located proximate an extended end of the upper arm, wherein the pellet hole is sized to accept a fusible pellet. An upper portion of the pellet hole traverses through the upper arm and a lower portion of the pellet hole traverses through the lower arm so that when a fusible pellet is inserted into the pellet hole it holds the upper arm and the lower arm together in a spring loaded position.

An exit device located in a door frame having a door strike including a latchbolt assembly, a pushbar assembly, and a link assembly. The latchbolt assembly includes an extended position configured to engage the door strike, and a retracted position configured to move past the door strike. The pushbar assembly moves from a released position to a pressed position to move the latchbolt assembly from the extended position to the retracted position. The link assembly is operatively connected to the pushbar assembly and includes a security link having an elongated aperture and a pin configured to extend through the elongated aperture about which the security link rotates. A keeper surrounds the pin and supports the security link for rotation. In the event of extreme heat, the keeper melts and the security link moves to a position to substantially prevent opening of the door.

A latch control device includes a connecting seat divided by two integrally formed walls into a hollow portion and a mounting portion spaced from the hollow portion. A detecting module is disposed between the two walls. A locking member is pivotably mounted between the two walls. A first restraining member is disposed in the mounting area and is configured to lock or unlock the locking member, controlling pivotal movement of the locking member. When the locking member is not pivotable, a latch of a door lock in the hollow portion is restrained in the hollow portion, preventing opening of a door to which the door lock is mounted. When the locking member is pivotable, the locking member can pivot while the door pivots, permitting opening of the door.

A fire door operator for a rolling door includes a housing defining an axis. An outer main gear in the form of an annular ring is mounted within the housing for rotation about the axis and formed with exterior gear teeth and radially inwardly spaced interior teeth. Planet gears are meshed with the interior teeth and a sun gear is meshed with the planet gears for rotation about the axis. A carrier is secured to the planetary gears and coupled to the shaft. A lock normally locks the main gear in relation to the housing. A drive selectively rotates the sun gear and the carrier to transmit rotational power to a rolling door shaft when secured to the carrier. A releasing device selectively releases the lock to allow free rotation of the main gear and the carrier to allow a rolling door to be lowered under its own weight.

An exit device located in a door frame having a door strike including a latchbolt assembly, a pushbar assembly, and a link assembly. The latchbolt assembly includes an extended position configured to engage the door strike, and a retracted position configured to move past the door strike. The pushbar assembly moves from a released position to a pressed position to move the latchbolt assembly from the extended position to the retracted position. The link assembly is operatively connected to the pushbar assembly and includes a security link having an elongated aperture and a pin configured to extend through the elongated aperture about which the security link rotates. A keeper surrounds the pin and supports the security link for rotation. In the event of extreme heat, the keeper melts and the security link moves to a position to substantially prevent opening of the door.

A backplate for a door actuator includes at least one first mounting element and a second mounting element, wherein one of the two mounting elements is formed for fastening to a mounting surface, in particular door, casing or wall, and the other mounting element is formed for receiving the door actuator. The backplate also includes, at least one connecting assembly, which in a retaining position, keeps the two mounting elements together and, in a release position, does not keep the two mounting elements together, and at least one shape memory assembly with a shape memory element made from shape memory material, wherein, upon thermal activation, the shape memory assembly moves the connecting assembly to the release position.

In one aspect the present invention provides a door strike which prevents the opening of an associated door when the door strike has been heated to an elevated temperature of at least about 1000° F., preferably when the door strike is at higher temperatures such as are present during a fire in a building structure. The door strike includes a thermally responsive element which retards the normal operation of the door strike when it is at an elevated temperature. A further aspect of the invention is a method for controlling the undesired spread of a fire or smoke between adjacent spaces separated by the door wherein a fire or smoke condition exists in at least one of these spaces, via the provision of a door strike having a thermally responsive element which retards the normal operation of the door strike when it is at an elevated temperature.

A power transfer device for a fire door operator having a pair of drive gears includes a bridge gear box having a drive shaft suitable for being coupled to an external drive. An idle spur gear is fixed to the drive shaft. A pair of spur gears are coupled to the idle spur gear to rotate in response to rotations of the idle spur gear. Spur gear shafts are coupled to the spur gears and arranged to be coupled to the drive gears of the operator so that rotation of the drive shaft by an external drive is translated to simultaneous rotations of the drive gears of the operator.

A hot melt safety door holder device includes: a first fixing part on one side of swing end of swing door sheet; a holder with a transverse through hole and the outer hole end faces towards the first fixing part; a second fixing part in the transverse through hole, the first radial end faces towards the outer hole end of transverse through hole, the second radial end faces towards the inner hole end; a conically cylindrical space, formed between the periphery of the second fixing part and the transverse through hole, and the inside and outside diameters of the end between the transverse through hole and the second fixing part corresponding to the space tapering end of conically cylindrical space are fitted with each other. The shape of the low-melting metal material filled in the conically cylindrical space matches the shape of conically cylindrical space, resulting in equal wall thickness.

A latch control device includes a connecting seat divided by two integrally formed walls into a hollow portion and a mounting portion spaced from the hollow portion. A detecting module is disposed between the two walls. A locking member is pivotably mounted between the two walls. A first restraining member is disposed in the mounting area and is configured to lock or unlock the locking member, controlling pivotal movement of the locking member. When the locking member is not pivotable, a latch of a door lock in the hollow portion is restrained in the hollow portion, preventing opening of a door to which the door lock is mounted. When the locking member is pivotable, the locking member can pivot while the door pivots, permitting opening of the door.