月: 2022年12月

What Is a Washer Head Screw?

A washer head screw is a screw with an integrated washer in its design. These screws are designed to securely join parts together, providing a strong bond. The incorporation of washers improves the stability of the joint, helping to withstand vibration and shock, and reducing the likelihood of loosening.

Washer head screws are also convenient for assembly work, as the built-in washer part simplifies the process and enhances work efficiency by reducing the need for re-tightening.

Applications of Washer Head Screws

Washer head screws are used in various industries and applications:

1. Automotive

In automotive assembly and repair, these screws are used in engine assembly, chassis, body panel assembly, and interior panel installation, providing stable joints capable of withstanding vibrations and impacts.

2. Electronic Equipment

Used in assembling circuit boards and enclosures in electronic equipment, these screws help in securely joining enclosure parts, preventing shifting or loosening due to vibration and shock.

3. Furniture Manufacturing

In the furniture manufacturing industry, washer head screws are used to attach metal parts to wood, ensuring stability and durability. They are also user-friendly for furniture that requires assembly by the consumer.

Principle of Washer Head Screws

These screws are typically made by first manufacturing the screw head and then pressing the washer through the head side, making the washer a permanent part of the screw. The manufacturing process usually leaves an unthreaded area near the base of the washer, known as the imperfectly threaded area, which must be considered when fixing thin plates.

How to Select Washer Head Screws

When choosing washer head screws, consider the following:

1. Head Shape

Select the head shape based on the tool used and the space available. Hexagonal heads are useful in tight spaces, while aesthetically pleasing head shapes are preferable for visible areas.

2. Material

Choose materials based on the operating environment and application. Options include stainless steel for corrosion resistance and carbon steel for strength.

3. Length

Select the correct length to ensure a secure connection without causing internal collisions or failing to bond adequately.

4. Screw Pitch

Choose the right thread pitch, which is the distance a screw travels in one turn, to ensure the effective joining of parts. Pitch is typically expressed in metric or inch measurements.

What Is an Optical Connector?

An optical connector is designed for connecting fiber-optic lines, facilitating the complete connection of optical fiber cables for efficient optical signal transmission. These connectors allow for easy and reliable linkage of optical lines, simplifying installation and maintenance. Precision engineering ensures minimal optical loss, enhancing signal transmission and extending reach.

However, due to their precision, the contact area with the optical fiber must be clean to maintain signal quality and efficiency. Handling in clean environments and using protective caps is crucial.

Uses of Optical Connectors

Optical connectors are widely used across various industries:

• Telecommunications: In constructing fiber-optic networks for long-distance communication and high-speed data transmission.
• Data Centers: Connecting servers and storage systems for high bandwidth and signal quality.
• Other Applications: Including television broadcasting, medical and industrial equipment, and in the aerospace and defense sectors, where high-speed and stable data transmission are crucial.

Principle of Optical Connectors

An optical connector typically comprises a housing and a ferrule holding the fiber end. It operates on the principle of direct end-to-end butting, requiring high-precision alignment to minimize connection loss. Connectors are typically mated using an optical adapter with a split sleeve for alignment. The connector ends are often PC-polished (spherical polishing) to avoid air layer formation and achieve minimal loss connections.

Types of Optical Connectors

Common types of optical connectors include:

• SC (Subscriber Connector): Features a cylindrical ferrule with a push-pull latching mechanism, commonly used for single-mode fiber optic cables.
• LC (Luciferous Connector): Small form factor connectors, suitable for high-density cabling environments and used for both single-mode and multimode fibers.
• ST (Straight Tube): Utilizes a bayonet coupling mechanism, ideal for multimode fibers, often used in network equipment and data communication applications.
• FC (Fiber Connector): Features a threaded coupling mechanism, offering durability and high signal quality, typically used in industrial and defense applications for single-mode fibers.

What Is a Ceramic Screw?

Ceramic screws, manufactured from ceramic materials, offer unique properties suitable for various applications. Their resistance to high temperatures and chemicals makes them ideal in environments like industrial furnaces where such conditions are prevalent. Additionally, their electrical insulation properties are beneficial in electronic and electrical circuits, preventing interference with adjacent components.

However, ceramics are more brittle than common metals and are vulnerable to shock and vibration, leading to a higher risk of breakage under excessive loads or impacts. They are often more costly than metal materials, necessitating careful consideration of cost constraints.

Applications of Ceramic Screws

Ceramic screws are used in specific environments due to their unique properties:

1. High-Temperature Environments

With excellent heat resistance, ceramic screws are used in casting and welding processes, and in areas where high temperatures surpass the endurance of metal screws.

2. Chemical Industry

In the chemical industry, ceramic screws are favored for their resistance to corrosive substances, often used in acidic and alkaline environments.

3. Electronics

As insulators, ceramic screws are advantageous in securing circuit boards in electronic equipment and high-voltage areas requiring insulation. They are also suitable for high-frequency and microwave signal transmission.

4. Medical Devices

Due to their high biocompatibility, ceramic screws are used in medical devices and dental tools, such as artificial joints and dental implants, playing a crucial role as components introduced into the human body.

Principle of Ceramic Screws

Ceramic screws are available in various shapes like hexagon socket head cap screws, pan head screws, flat head screws, and mounting screws, allowing selection based on application needs. They are produced using standard ceramic processing methods such as cutting and forming. Forming methods include press forming and extrusion while cutting involves shaping ceramics using machine tools such as lathes, machining centers, and milling machines.

Post-formation, parts undergo sintering at high temperatures to bond ceramic particles and strengthen the structure. The sintering process varies in temperature and time based on the material. Ceramic screws may also receive surface coatings or protective layers to enhance wear and corrosion resistance.

How to Select Ceramic Screws

Consider the following when choosing ceramic screws:

1. Screw Shape

Select the screw shape based on installation efficiency and fastening needs. Button head or flat head screws are suitable for applications requiring close adhesion, while truss head screws distribute pulling force more evenly.

2. Dimensions and Screw Diameter

Choose screw dimensions and diameters to match the application and ensure secure fastening. Metric screw diameters, typically prefixed with ‘M’, are commonly used.

3. Types of Ceramics

Various types of ceramics offer different properties. Select ceramics with high heat resistance for high-temperature environments and those with excellent corrosion resistance for chemical environments. Choose the ceramic type that best suits the application’s requirements.

What Is a Cap Screw?

A cap screw is a bolt with a cylindrical or countersunk bolt head and a hexagonal hole drilled in its upper end face.

Generally, “cap screw,” “socket screw,” and “hexagon socket head cap screw” are also used as synonyms.

The standards for cap screws are as follows:

• ASME/ANSI B18.3 Hexagon Socket Head Screws

Usage of Cap Screws

Figure 1. Example of cap bolt use (1)

Cap screws are primarily used to mount and secure components on small machines and equipment where space is limited for installation.

To tighten cap screws, use a tightening tool such as a hexagonal wrench (Allen wrench) appropriate for the size of cap screw. Compared to a wrench or a monkey wrench, a hexagonal wrench has the advantage of applying a stronger tightening force with less force and requiring less work space around the bolt when tightening.

Figure 2. Example of cap bolt use (2)

However, since hexagonal wrenches are available in millimeter and inch sizes, care must be taken in selecting a hexagonal wrench. Also, by drilling a counterbored hole slightly larger than the diameter of the cylindrical head of the cap screw and slightly deeper than the height of the head, the cap screw can be installed without the head protruding.

Counterbore holes are drilled in the mounting area so that the bolt head is hidden. The interference between the bolt head and other parts is avoided, resulting in a clean and neat appearance.

Principle of Cap Screws

Cap screws are fastened by means of a screw (in this case, “screw” refers only to the screw shape), the same as an ordinary hexagonal bolt. Cap screws are often used to fasten directly onto a tapped female thread without using a nut.

Instead of inserting a wrench into the bolt head like a hexagonal bolt, a wrench with a hexagonal cross section is inserted into the hexagonal hole and tightened. For this reason, it is necessary to secure a space between the bolt heads and other parts. However, the cap screw tightening tool does not require space outside the bolt head because of the hexagonal wrench, allowing the cap screw to be placed close together.

Used when high tightening force and high strength are required. It is important to select the appropriate material and strength classification for the location and application.

Types of Cap Screws

Figure 3. Type and shape of cap bolts (1)

Cap screws are classified by the shape of the cap screw head and the shape of the hole for the fastening tool.

Types by cap screw head shape are as follows:

• Hexagon socket head cap bolt
• Hexagon socket low head bolts
• Hexagon socket countersunk bolt
• Hexagon socket button bolt

Figure 4. Type and shape of cap bolts (2)

In addition to the hexagonal hole, there is a hexagonal star-shaped groove Torx hole.

Other Information on Cap Screws

Tightening Tools for Cap Screws

Figure 5. Type and shape of cap bolt tightening tool

The most commonly used tools for tightening cap screws are L-shaped Allen wrenches (hexagonal bar wrenches), T-handle Allen wrenches, screwdriver Allen wrenches, and hexagonal bits. Hexagonal wrenches and hexagonal bits have either a “flat” or “ball point” tip shape on the side where the cap screw is inserted.

The shape of the tip of the ballpoint is R-processed at the corner so that the hexagonal wrench can be tightened even when the hexagonal wrench is at an angle.

What Is a Tool Balancer?

A tool balancer is a device that suspends tools, such as hand tools, via a wire or air hose in areas where manual labor is performed.

When a suspended tool is used, the wire or air hose extends to the length pulled and retracts to its original length when released. This feature allows the tool to be kept out of the way when not in use, maintaining a tidy workspace and improving work efficiency. Tool balancers are also beneficial for suspending heavy tools that are difficult to hold for extended periods.

Uses of Tool Balancers

Tool balancers are utilized in various workplaces to suspend tools for manual tasks. Common settings include automotive assembly lines, machine tool setup areas, and electrical product assembly lines.

Tools typically suspended include hand tools such as wrenches, electric screwdrivers, air impact wrenches, and air guns. Using multiple tool balancers allows for the selection and use of the necessary tools as needed.

Principles of Tool Balancers

Tool balancers are designed to exert a force on the wire that slightly exceeds the weight of the tool, ensuring smooth extension and retraction. The wire extends when a tool is pulled and retracts to its original length upon release.

The primary mechanisms for generating rewinding force are springs and electric motors. In spring-operated balancers, the winding force increases with the length of wire unwound. To counteract this and maintain a constant pulling force, the winding section is designed with a tapered helix shape, allowing the radius to increase as the spring’s elastic force grows. Electric motor types adjust the take-up torque based on the weight of the suspended tool.

For suspending air tools, an air hose is used in place of wire in tool balancers. The hose is designed to withstand the force of suspending the tool while also providing an internal air channel to supply air to the tool.

What Is a Combination Air Filter/Regulator/Lubricator (FRL)?f

An FRL combination refers to three pieces of air equipment installed in the middle section of a pneumatic circuit. The components are a filter, a regulator, and a lubricator. It is also called a “three-piece air set” and has been used for a long time.

They are mainly installed in pneumatic circuits to supply air normally. The capacity and other factors are considered and installed according to the operating pressure and the amount of air used. During maintenance, it is necessary to remove water from the filter and replenish the lubricator drive oil.

Uses of FRLs

Rarely an air combination unit is not installed where pneumatic equipment is installed.

They are installed in front of the pneumatic devices that drive the solenoid valves, air cylinders, etc., and are used to protect these devices. Filters are installed to remove moisture, regulators to optimize pneumatic pressure, and lubricators to lubricate drive units. Many oil-free pneumatic systems have been available in recent years so the lubricator may be omitted.

Principle of FRLs

An air combination is divided into three parts, the filter, regulator, and lubricator, each of which has its role.

The filter is initially used to remove moisture from compressed air. Compressed air used in pneumatic circuits contains a lot of moisture. If compressed air is introduced into the drive unit in this state, the moisture will corrode the drive unit. In addition, the drive unit is coated with grease to ensure smooth operation, and the moisture may wash away the grease. Therefore, a filter is used to remove the moisture first.

Next, a regulator maintains the optimum pressure for the equipment. The drive unit has a fixed allowable air pressure, and if the air pressure exceeds the upper limit, the drive unit may fail. The regulator reduces the pressure to prevent excessive pressure from being applied to the drive unit.

Finally, although the drive unit is coated with grease in advance, air pressure and humidity gradually deplete the grease. To supplement this grease, drive oil is supplied by a lubricator.

Thus, the FRL combination is a component that preserves the air drive system through three elements.

What Is a Selector Switch?

A selector switch is a switch that selects from multiple options. Typically featuring a disk-shaped or square knob, it can be rotated to choose different options. These switches are simple to operate, allowing quick selection by turning the knob. This is especially useful when multiple choices or modes are available.

Selector switches are mechanically operated, ensuring reliable and trustworthy operation. However, they are limited to selecting from a predefined set of options and may not accommodate new choices or settings without modification.

Uses of Selector Switches

Selector switches have various applications, including:

1. Audio Equipment

In audio equipment, selector switches are used to choose different input sources and control volume levels, facilitating user preference for music or content and volume adjustments. They often include switches for sound effects and equalizer settings.

2. Industrial Control Panels

In industrial control panels, selector switches are employed to alternate between operating modes of manufacturing processes, such as starting/stopping a production line or switching production modes. They are crucial for manual control by operators.

3. Electronics

In electronics, selector switches enable switching between different operational modes or settings, like adjusting camera settings or changing phone modes. They simplify and expedite function changes.

Principle of Selector Switches

Selector switches operate by physically switching between different electrical circuits. They consist of a knob or lever, contacts, and a housing. Inside, electrical contacts made from conductive materials like copper, silver, or gold, open and close with the knob’s movement, forming circuits for electric current flow.

The external case, typically hard plastic, insulates the conductive parts and provides protection and stability during use.

How to Select a Selector Switch

When choosing a selector switch, consider:

1. Number of Notches

The number of notches represents the switch’s options or positions. Select based on the required choices.

2. Frame Dimensions

Frame dimensions are crucial for ensuring adequate mounting space on the device or panel. Consider dimensions, especially if placing multiple buttons on the same panel.

3. Contact Configuration

Contact configuration refers to the contact system for each option. Choose the number of contacts and their operation at each position based on the application.

4. Return Method

The return method determines if the switch automatically returns to its original position after use. Non-return types stay in the selected position, while return types revert. Non-return is suitable for applications requiring consistent selection rather than temporary operation.