An exemplary door closer includes a body, a regulation screw, and an indicator. The body includes a surface and a cavity extending from the surface into the body, and the cavity includes an internal threading. The regulation screw is mounted in the cavity and includes an external threading engaged with the internal threading. The indicator is engaged with the regulation screw and positioned at least partially within the cavity. The indicator is positioned to project beyond the surface when the regulation screw is withdrawn to a reference position relative to the body.

Certain embodiments relate to an adjustment indicator mechanism for a door closer including a tubular portion and an adjustment screw mounted to the tubular portion. A housing is configured for mounting to the door closer, and includes a channel and indicia adjacent the channel, each of the indicia corresponding to a respective size of the door closer. An adjustment transmission includes a first component configured for coupling with the adjustment screw. An indicator transmission is engaged with the adjustment transmission and mounted in the housing. An indicator is movably mounted to the housing such that a portion of the indicator is visible via the channel. The indicator is engaged with the indicator transmission such that movement of the indicator transmission causes the indicator to selectively align with the indicia to thereby indicate the current size of the door closer.

A driving device for a door opener includes a motor driving a first transmission member to rotate. Rotation of the first transmission member causes lateral displacement of a sliding member which moves jointly with a connecting rod. A return spring is mounted around the connecting rod. An adjusting ring is in threading connection with the connecting rod and abuts against the return spring. When the first transmission member does not rotate, rotation of the adjusting ring causes displacement of the adjusting ring in the lateral direction to change an extent of pre-compression of the return spring. When the first transmission member rotates in a direction, the connecting rod and the adjusting ring together move in the lateral direction towards the first transmission member, and the return spring is compressed. When the first transmission member rotates in a reverse direction, and the return spring restores its length.

An exemplary method involves operating a door operator coupled to a door. The door operator includes a motor operable to move the door in at least one direction and a controller operable to control the motor. The method generally involves a calibration procedure including: with the door at a first position and the door having an initial speed, initiating, by the controller, measurement of a time duration; in response to the door reaching a target speed different from the initial speed, ceasing, by the controller, measurement of the time duration; and determining, by the controller, a maximum speed based on the time duration. The method further includes performing at least one operation based upon the maximum speed.

An example door closer includes a casing and a pinion rotatably mounted to the casing. The pinion is operable to rotate through a plurality of movement zones, and the door closer is configured to exert forces on the pinion as the pinion moves through the plurality of movement zones. The door closer further includes a plurality of adjustment mechanisms, each operable to adjust the force exerted on the pinion as the pinion travels through a corresponding movement zone. The casing is provided with indicia that correlate each of the adjustment mechanisms to the corresponding movement zone.

An exemplary door closer has an adjustable size and includes a rotatable member operable to adjust the size and an indicator mechanism configured to indicate the current size. The indicator mechanism includes a cover mounted to a housing of the door closer and a dial rotatably mounted to the cover. The dial is engaged with the rotatable member such that the dial rotates in response to rotation of the rotatable member. The cover includes an indicating region, and the dial includes a display surface including indicia relating to the sizes of the door closer. The display surface is non-perpendicular to the rotational axis of the rotatable member. When the door closer has been adjusted to a particular size, indicia relating to the particular size are indicated by the indicating region.

One embodiment relates to a door operator including an operator body including a rotatable pinion, an arm connected to the pinion, an inductive sensor mounted adjacent the arm, and a controller in communication with the inductive sensor. The inductive sensor includes an inductor comprising a plurality of nested coils, and each of the coils is curved about the pinion. The controller is configured to provide the inductive sensor with a varying power signal, and the inductive sensor is configured to inductively link the inductor to the arm in response to the varying power signal. The inductive sensor has a characteristic which varies in response to the rotational position of the arm when the inductor is inductively linked with the arm. The controller is further configured receive information relating to the characteristic, and to determine the rotational position of the arm based upon the received information.

A closing device includes an actuator mechanism and a hydraulic damper mechanism. The actuator mechanism includes a pushrod urged by a resilient member towards its extended position. The hydraulic damper mechanism includes a piston, a first rack and pinion gearing for converting the translational motion of the pushrod into a rotational motion of a first pinion, a transmission, which includes a second rack and pinion gearing, between the first pinion and the piston for transmitting and converting the rotational motion of the first pinion into a translational motion of the piston, a one-way valve allowing fluid flow from a first side to a second side of the cylinder cavity when opening the hinged member, and a restricted fluid passage between the first and second sides of the cylinder cavity. The transmission provides together with the pinions of the first and second rack and pinion gearings a reduction gearing between the pushrod and the piston so that the piston reciprocates over a smaller distance than the pushrod.

An example door closer includes a casing and a pinion rotatably mounted to the casing. The pinion is operable to rotate through a plurality of movement zones, and the door closer is configured to exert forces on the pinion as the pinion moves through the plurality of movement zones. The door closer further includes a plurality of adjustment mechanisms, each operable to adjust the force exerted on the pinion as the pinion travels through a corresponding movement zone. The casing is provided with indicia that correlate each of the adjustment mechanisms to the corresponding movement zone.

An automatic door operator is disclosed, including: an actuating unit configured to output torque; a lead screw having a first end connected to an output end of the actuating unit and a second end extending away from the output end; a lead screw nut screwed to the lead screw; a slider attached to the lead screw nut, the slider being provided with a rack portion extending in a direction parallel to an axial direction of the lead screw, and during a movement of the lead screw nut from a first extreme working position away from the first end of the lead screw to a second extreme working position close to the second end of the lead screw, a length of an overlap between the rack portion and the lead screw in the axial direction gradually increasing; a housing having a guide hole configured to be slidably engaged with the slider; and an output shaft mounted in a mounting hole disposed on the housing, the output shaft having a gear portion positioned in the guide hole and engaged with the rack portion. The automatic door operator is high in transmission efficiency, small in size and low in running noise.