Hardware accessories are the key components that determine the performance of doors and windows. The design of doors and windows is primarily based on the architectural design of door and window performance, with the goal of meeting the functional requirements of the building, and reasonably determining the performance and related design requirements of doors and windows. Hardware accessories are the components responsible for tightly connecting the frames and leaves of doors and windows. Without their existence, doors and windows would only become dead leaves and lose their meaning. What are the hardware accessories for doors and windows? The main hardware accessories for doors and windows include: door closers, window openers, hinges, hinges, guide rails, pins, sealing strips, pulleys, hand cranks, handles, glass clips, etc.

（1） What is a door closer?

Automatic door closer, also known as door spring, can generally be divided into three categories based on its installation position: door top closer, door bottom spring, and floor spring. The external door closer is equipped with a hydraulic buffer oil pump device, which can automatically close the door when it is opened. Its main feature is that the door closes slowly and there is no collision sound after closing. It can be used on the doors of schools, hospitals, office buildings, hotels, and other places. Embedded door top closer, as it is installed in the groove of the door leaf and frame, does not affect the appearance of the door when it is closed. It is suitable for use on the doors of high-end hotel rooms. Door bottom spring, also known as automatic door bow, is available in two types: horizontal and vertical. Its function is equivalent to a double spring hinge, which can automatically close the door leaf when it is opened. When the door leaf does not need to close automatically, open the door leaf to 90 °. The bottom spring of the door can be used on spring-loaded wooden doors or doors that open both inside and outside. The ground spring consists of two main parts: upper and lower. The upper structure consists of a top shaft and a top shaft sleeve plate, while the lower structure consists of a rotating shaft rod and a base. The ground spring not only allows the door leaf to automatically close, run smoothly, and have no noise, but also adjusts the speed of automatic closing of the door leaf. When the opening angle of the door leaf is less than 90 °, the doors and windows can be automatically closed in both directions inside and outside; When the door leaf is opened to 90 °, it can be fixed and not moved. This type of ground spring, due to its main structure buried underground, can maintain the appearance of the door leaf and is often used on the doors of more advanced buildings.

（2） What is a window opener? What are the types of window openers? Manual and electric window openers.

1. Manual window opener

The purpose of a manual window opener is to open ventilation windows in higher positions through a certain device. According to the principle of the thermal effect of air, the hot air and light harmful gases that should be eliminated can only be effectively eliminated through high positioned windows. A manual window opener generally consists of five parts: the executing component for opening the window (such as a scissor type window opener), the corner connector, the operating component, the connecting rod, and the decorative cover plate. The window opening execution component determines the width of the window, the weight of the window opener, and the presence or absence of locking function. Corner connectors are transmission components, and their deformation determines the ability of window openers to adapt to different window types and installation conditions. The operating components can be in the form of a handle or a joystick. The handle type operation has simple components and low cost. The power output of the rocker operated component is uniform, not easily damaged, requires high machining accuracy, and has high costs. The manual window opener is suitable for both lower hanging inner window opening and upper hanging outer window opening. The hanging outward window requires special outward opening accessories. From the analysis of the force situation of the window opener, the lower hanging inner window with the hinge located at the bottom is more labor-saving. The upper hanging outward opening window with hinges is more laborious, and it is important to be cautious when using a four link accessory, as the four link accessory will cause a significant settlement of the center of gravity of the window when it is opened. If the weight of the window is too large, the force of the window opener may not be enough to lift the window and close it.

2. Electric window opener

The simplest electric window opener is to match the mechanical window opening actuator with a driving motor and a switch. There are also rack and pinion window openers and chain window openers. However, from the requirements of product stability and service life, window openers need to be dustproof, moisture-proof, and even waterproof. Dust accumulation can cause wear and tear on the window opener, moisture can rust the window opener, and water can short-circuit the circuit of the window opener. The condensation caused by changes in indoor relative humidity is a common occurrence in buildings with poor window insulation performance or changes in indoor environment, especially in greenhouse buildings. A comprehensive and thorough analysis and understanding of the environmental conditions under which window openers are used is crucial for selecting the right type of window opener. Internationally, there is an internal screw type window opener for fully enclosed dustproof, moisture-proof, and waterproof windows. This type of window opener has a thrust of up to 1000 Newtons, low noise, and low power consumption. When choosing a window opener, it is also important to pay attention to whether its installation is convenient, as the installation conditions on the construction site may be very limited.

There are currently two types of automatic control systems for electric window openers. The greenhouse control system is a system that controls the opening and closing of windows based on the measured values of temperature, humidity, sunlight, wind intensity, and rainfall, and compares them with pre-set values.

Automatic smoke and heat exhaust system is a newly developed fire protection concept internationally, which means that when a fire alarm generates smoke and heat, the windows used for smoke and heat exhaust will automatically open. Due to the increasingly comprehensive fire protection requirements for building materials in modern architecture, the fire resistance performance of materials is precisely defined from the perspective of flame retardancy. Therefore, once a fire occurs, smoke and the harmful substances contained therein can cause more direct harm to personnel. Or in other words, harmful smoke hinders active rescue and passive escape behaviors. From the study of the development process of fires, it can be seen that in the initial stage of fire occurrence, a large amount of smoke and heat energy are first generated. Smoke rises and gathers on the upper floors of buildings due to the effect of heat.

（3） The main varieties of hinge hardware are divided into three types: room door hinges, drawer guides, and cabinet door hinges.

The door hinges are made of both full copper and stainless steel materials. The standard area of a single hinge is 10cm x 3cm and 10cm x 4cm, with a central axis diameter between 1.1cm and 1.3cm, and a hinge wall thickness between 2.5mm and 3mm. When selecting a hinge, in order to open it easily and without noise, it is better to choose a hinge with a central axis containing ball bearings. The drawer guide rail is divided into two types: two section rail and three section rail. When selecting, the brightness of the surface paint and electroplating, the gap and strength of the load-bearing wheel determine the flexibility and noise of the drawer opening and closing. A wear-resistant and evenly rotating load-bearing wheel should be selected.

Cabinet door hinges are divided into two types: detachable and non detachable. They are also divided into three types based on the covering position after the cabinet door is closed: large bend, medium bend, and straight bend. Generally, medium bend is the main type. When selecting hinges, in addition to visual inspection and smooth surface, attention should be paid to the good reset performance of the hinge spring. The hinge can be opened 95 degrees, and both sides of the hinge can be pressed with force by hand. The supporting spring pieces should not deform or break, and a very sturdy product is considered a qualified quality product.

（4） Sealing strip

All sealing strips are made of imported materials, which have strong anti-aging property and durability. After installation, your door can still be opened and closed freely and is beautiful and energy-saving.

（5） Handle

The materials of the handle include zinc alloy, copper, aluminum, stainless steel, plastic, logs, ceramics, etc. In order to match various styles of furniture, the shape and color of the handles are diverse and colorful. The handle, which has undergone electroplating and electrostatic spray painting, has wear resistance and corrosion resistance. When selecting it, in addition to matching the decoration style of the room, it should also be able to withstand a large tensile force. Generally, the handle should be able to withstand a tensile force of more than 6 kilograms