The present disclosure describes various embodiments of a concealed or hidden door closer that is installed in a rail of a door assembly. In some embodiments, the door frame and door closer components are configured to allow the door assembly to be readily installed as either a left or a right hand hinged door.

A coupling device for coupling folding elements of a folding device has first and second coupling elements that lock the folding elements relative to each other. The coupling device has a locking device with sliding element whose rearward part, when the second folding element is not closed, is in a rest position in which a locking member of the sliding element engages a locking receptacle of the first coupling element when the coupling elements are latched. In the rest position, the locking member contacts a guiding contour of the second coupling element and unlocking of the locking member from the locking receptacle by pulling on the coupling elements is prevented. When the second folding element is closed, the rearward part of the sliding element contacts the frame causing the locking member to move along the guiding contour out of the locking receptacle; the locking action is released.

An operator for a vehicle side door includes: a drive unit; a pinion gear fixed to an output shaft of the drive unit; a rack including a rack gear, the rack gear being configured to engage with the pinion gear; a connecting arm pivotally supported on a vehicle body side bracket fixed to the vehicle body, the connecting arm being connected to a front end of the rack; and a contact stopper fixed to a rear end of the rack, wherein the side door moves in a direction of opening the door when the rack moves forward by the rotation of the pinion gear and the side door moves in a direction of closing the door when the rack moves backward by rotation of the pinion gear, and the contact stopper is configured to come into contact with the drive unit when the rack moves forward by a specified amount.

A recording apparatus includes a lower unit including a recording unit that performs recording on a medium, and an upper unit including a reading unit that reads a document image, the upper unit being disposed above the lower unit and being configured to open and close with respect to the lower unit. The upper unit includes an arm that maintains an open state of the upper unit by being supported by the lower unit. The lower unit has a cam groove that receives a protrusion disposed on the arm and that has a route along which the protrusion moves in a certain direction when the upper unit opens or closes. A recess that the protrusion enters and that supports the protrusion from below is disposed in the cam groove and the open state of the upper unit is maintained by the protrusion entering the recess.

A door actuator linkage includes a lever extending along a longitudinal axis, which merges into a linkage head with an offset, wherein the linkage head is formed for rotationally fixed mounting on an output shaft of a door actuator, wherein a free space for cable routing is formed by the offset. The free space is delimited by the linkage head and by an offset surface of the lever, wherein the lever protrudes up to an imaginary boundary surface, which is defined perpendicular to the longitudinal axis. The offset surface is withdrawn partially from this boundary surface in order to expand the free space.

A pneumatic door closer includes a rotary energy-storing mechanism including a housing and a driving mechanism. The driving mechanism includes a cylinder, a second piston assembly and a sealing element, the sealing element is in an air tight connection with the cylinder and the second piston assembly, to form a closed space filled with high pressure gas in the cylinder. The second piston assembly drives the closed space into a first air chamber and a second air chamber in communication with each other. The driving mechanism also includes a first piston assembly connected to the second piston assembly. The pneumatic door closer also includes a transmission mechanism having one end received in the housing and another end connected to the door frame.

A pneumatic door closer includes a rotary energy-storing mechanism including a housing and a driving mechanism. The driving mechanism includes a cylinder, a second piston assembly and a sealing element, the sealing element is in an air tight connection with the cylinder and the second piston assembly, to form a closed space filled with high pressure gas in the cylinder. The second piston assembly drives the closed space into a first air chamber and a second air chamber in communication with each other. The driving mechanism also includes a first piston assembly connected to the second piston assembly. The pneumatic door closer also includes a transmission mechanism having one end received in the housing and another end connected to the door frame.

A door driving mechanism for connecting a door operator (30) to a swing door leaf (14) is provided. The door driving mechanism comprises a guiding member (22) fixedly arranged to the door leaf (14); and a driving arm (24) at one end being rotationally driven by the door operator (30), wherein said driving arm (24) is slidably connected to the guiding member (22) at a fixed position in relation to the door leaf.

A pneumatic door closer includes a rotary energy-storing mechanism including a housing and a driving mechanism. The driving mechanism includes a cylinder, a second piston assembly and a sealing element, the sealing element is in an air tight connection with the cylinder and the second piston assembly, to form a closed space filled with high pressure gas in the cylinder. The second piston assembly drives the closed space into a first air chamber and a second air chamber in communication with each other. The driving mechanism also includes a first piston assembly connected to the second piston assembly. The pneumatic door closer also includes a transmission mechanism having one end received in the housing and another end connected to the door frame.

The present invention relates to novel lignin-derived compounds and compositions comprising the same and their use as redox flow battery electrolytes. The invention further provides a method for preparing said compounds and compositions as well as a redox flow battery comprising said compounds and compositions. Additionally, an assembly for carrying out the inventive method is provided.