月: 2024年1月

What Is a Light Guide?

A light guide, or light guide plate, is an optical component that captures and directs light from a peripheral light source, such as LEDs, to a desired area.

There are two main types: injection-molded light guides and optical fiber light guides. Injection-molded light guides, made from transparent materials like polymethyl methacrylate (PMMA) or polycarbonate (PC), offer design flexibility and can be shaped into various forms like strips or circles, tailoring light distribution and brightness. Optical fiber light guides, typically produced through extrusion molding, are limited to certain cross-sectional shapes but do not require individual molding dies, reducing initial costs.

Optical fiber light guides are bendable and distribute light uniformly without specific optical design. However, they may not be ideal for directional illumination or brightness control.

Uses of Light Guides

Light guides are used in various applications, including automotive interior lighting, industrial equipment, and household appliances. They allow for efficient, uniform light distribution, even from distant LEDs. Automotive applications include bright line lights, backlighting for switches, and lighting for ports and indicator lights.

Injection-molded light guides provide adjustable light direction and are classified into blast, prism, and dot methods, each with distinct illumination characteristics. The blast method offers uniformity without visible patterns, while the prism method is brighter but not suitable for direct illumination. The dot method balances brightness and pattern visibility.

Principles of Light Guides

Light guides manipulate light emission through surface features like protrusions or scattering effects. In a transparent, mirror-like acrylic part, light enters one side, reflects internally, and exits the opposite side. Surface features can scatter light, allowing it to exit in various directions, achieving desired lighting effects.

Structure of Light Guides

Light guides consist of bundled optical fiber strands, encased in a protective steel tube, with socket caps on both ends. Strand types vary based on intensity, wavelength, and heat requirements. Optical processing methods include prism processing, embossing, and dot processing, each providing different lighting effects.

Branching structures in light guides allow light from a single source to be distributed through multiple outlets. While this reduces the number of light sources needed, branching can diminish the light intensity from each outlet.

How to Choose Light Guides

When selecting light guides, consider the application’s specific needs. Optical fiber light guides offer flexibility and uniform line illumination but may require fixed structuring. Injection-molded light guides, while requiring initial investment for molds, are more cost-effective for mass production of similar shapes.

What Is a Spring Washer?

A spring washer is a washer designed to prevent the loosening of bolts or screws through its spring action.

The simplest form, known as a coil spring washer, is created by cutting a metal ring at one point, bending the end upwards, forming a single-layered, spring-like device. It is typically used in conjunction with a flat washer under the head of a bolt for joining components.

When using a spring washer, it is threaded onto the bolt first, followed by a flat washer. The bolt then passes through the components being joined and is secured on the other side with a flat washer and nut. The spring washer exerts continuous force, ensuring the bolt and nut remain tightly fastened.

Spring washers come in various designs, such as coil and wave spring washers, each providing enhanced anti-loosening effects.

Uses of Spring Washers

Spring washers are crucial in fastening applications, stabilizing connections between components and preventing bolt and nut loosening. They are used in machinery, engines, automotive suspensions, and the interiors of household appliances and electronic devices. Some types are also designed to improve electrical contact or absorb vibrations and impacts.

Principles of Spring Washers

Spring washers work by applying opposite force to the bolt or screw head, thereby increasing friction between the bolt and nut threads, preventing loosening. This principle also applies when used with screws, enhancing friction between the screw threads and the threads of the joined component’s hole.

Types of Spring Washers

Selection of spring washers depends on the intended application, target use, and operating environment.

1. Coil Spring Washer

A coil spring washer, resembling a conical shape, is coiled into one or more turns. As a compression spring washer, it generates rebound force when compressed by a tightened bolt, preventing loosening.

2. Wave Washer

A wave washer, or wave spring washer, is a flat circular ring that distorts under external force, generating a counterforce against the bolt’s threads. It is used for lighter tightening applications, offering anti-loosening and anti-rattling benefits.

3. Titanox

Titanox is a high-performance washer that prevents both reverse rotation loosening and loosening due to material contraction. It features a tapered magic ring for preventing reverse rotation and a circular plate spring to maintain force against material contraction. Titanox is particularly effective in wooden structures, mitigating loosening over time.

What Is a Lock Washer?

Lock washers, designed to prevent loosening of bolts, screws, and nuts, play a vital role in securely fastening components together.

A washer is a thin metal ring placed between the head of a bolt (or screw) and the nut. Its primary functions are to prevent loosening and to protect the surface of components from damage during tightening.

Various types of lock washers exist, including nord-lock washers, ribbed-lock washers, spring washers, belleville washers, conical spring washers, and serrated conical spring washers.

Uses of Lock Washers

Lock washers are essential in machinery and vehicles subject to intense vibrations, preventing loosening that could lead to malfunctions or accidents. High-performance lock washers like nord-lock and ribbed lock washers are particularly effective in preventing both rotational and non-rotational loosening.

They are also crucial in electrical and precision machinery, where contact resistance is key. Lock washers increase the contact area, enhancing electrical signal transmission and reducing resistance.

In outdoor or humid environments, corrosion-resistant lock washers made of stainless steel or titanium are used to prevent rust and corrosion by creating a gap between the bolt or nut and the joined material.

Principles of Lock Washers

Lock washers address two main causes of loosening:

Rotational loosening: Caused by vibrations leading to reverse rotation of the bolt or nut.

Non-rotational loosening: Due to material contraction, such as in wood.

Types and principles:

1. Nord-Lock Washer

Nord-lock washers, with their unique two-piece serrated design, prevent rotational loosening by increasing tightening force when a bolt attempts to rotate in the opposite direction.

2. Ribbed-Lock Washer

Ribbed lock washers, with tapered ribs, embed into bolt seats and materials, maintaining tightening force over time to prevent rotational loosening.

Spring washers, with their simple spring-like design, offer cost-effective protection against both rotational and non-rotational loosening. Serrated conical spring washers provide enhanced resistance against loosening due to their serrated surface.

How to Choose Lock Washers

Selection of lock washers should be based on the specific causes of potential loosening, such as vibration, corrosion, or material contraction. Factors like size, type of screws, operating environment, and required resistance properties should guide the choice of washer.

Other Information on Lock Washers

About Magic Ring

The magic ring on titanox washers is a wedge-shaped mechanism that converts vibrations into increased tightening effects. This feature is particularly effective against vibrations from natural events or machinery, ensuring long-term strength and reliability in wooden structures.

What Is WBGT?

WBGT, or wet-bulb globe temperature, is an indicator used to assess heat stress risks in extremely hot environments.

Also known as the wet-bulb black globe temperature or heat stress index, WBGT considers humidity, temperature, and radiant heat, which significantly impact the body’s heat balance. It can be calculated using dry-bulb temperature (Td), wet-bulb temperature (Tw), and black-bulb temperature (Tg). In the presence of solar radiation, WBGT is expressed as WBGT = 0.7Tw + 0.2Tg + 0.1Td. In indoor or shaded conditions, it is WBGT = 0.7Tw + 0.3Tg.

The dry-bulb temperature is the air temperature measured by a thermometer. The wet-bulb temperature indicates air and vapor characteristics. The black-bulb temperature, measured using a virtual blackbody sphere (also known as globe temperature Tg), reflects radiant heat exposure. All measurements for WBGT, Tg, Tw, and Td are in degrees Celsius (°C). Airflow influences black-bulb and wet-bulb temperatures, thus being incorporated into WBGT calculations.

Uses of WBGT

First proposed in the United States in 1954 to prevent heatstroke, WBGT was adopted at U.S. military training facilities for its effectiveness. Now, it is an internationally recognized guideline for sports and occupational environments, standardized by ISO.

WBGT is a standard for sports activities and is also used in workplaces and daily life to ensure comfort and avoid overexertion in hot and humid conditions. Regular reassessment of work environments and practices like salt and fluid replenishment, prioritizing sleep, and ensuring adequate ventilation are crucial. WBGT serves as a vital indicator for maintaining safe conditions.

Principles of WBGT in Preventing Heat Stroke

• WBGT below 21: Low heatstroke risk, but caution needed in events like marathons.
• WBGT 21-25: Increased risk of heatstroke; stay hydrated and watch for symptoms.
• WBGT 25-28: Regular breaks recommended, especially during intense activities.
• WBGT 28-31: High heatstroke risk; limit intense activities and take frequent breaks.
• WBGT above 31: Exercise should be discontinued, particularly for children.

Guidelines for daily life include:

• WBGT below 25: Low risk but caution during intense activities.
• WBGT 25-28: Incorporate breaks during vigorous activities.
• WBGT 28-31: Avoid outdoor exposure in hot weather.
• WBGT above 31: High risk for older adults; stay indoors and avoid heat exposure.

Types of WBGT

WBGT calculations are based on three measurements: dry-bulb, wet-bulb, and black-bulb temperatures.

1. Dry-Bulb Temperature

Direct air temperature measurement using a standard thermometer.

2. Wet-Bulb Temperature

Measured with a thermometer wrapped in wet gauze, indicating equilibrium temperature with cooling from water evaporation.

3. Black-Bulb Temperature

Measured using a thermometer in a black-painted, thin copper ball, reflecting perceived temperature in shaded conditions.

How to Choose WBGT

WBGT values can be determined using online heat index information or by using a WBGT measuring device for more accurate readings. Handheld types, prevention guideline-based types, and large-display types are available, though accuracy can be affected without a black bulb for measuring solar and radiant heat.

What Is Protective Clothing?

Protective clothing is specialized apparel designed to prevent health hazards caused by environmental conditions during work. It is essential in occupations where regular clothing or work attire poses significant health risks. These garments vary, tailored to address specific threats in different work environments.

Common examples include firefighting gear, known for its heat and flame resistance, and dust-resistant clothing for dusty environments with. Chemical protective clothing is used for handling toxic substances, while infection prevention clothing is vital in medical settings to prevent virus transmission. These garments typically cover the entire body and may include wind resistance, helmets, eyewear, masks, gloves, and shoes. Some are designed for single-use, emphasizing the importance of proper handling and disposal.

Uses of Protective Clothing

Protective clothing caters to a variety of applications, each suited to specific work environments. For instance, dust-resistant clothing is essential in industries like metalworking, cleaning, and food processing. High-pressure washing protective clothing is used in tasks involving chemicals or high-pressure water jets. Different types of protective clothing are essential for safety and health in diverse work settings.

Principles of Protective Clothing

Protective clothing combines multi-layered materials to shield against health hazards. These fabrics offer breathability, insulation, and heat dissipation, ensuring wearer protection without compromising comfort. Dust-resistant clothing, for example, uses particle-impermeable fabrics, while high-pressure washing protective garments are made of water-resistant, durable materials. The challenge lies in balancing maximum protection with comfort and usability.

Types of Protective Clothing

Additional types of protective clothing include:

• Chemical Protective Clothing: Provides protection against hazardous substances, available in various forms like full-body suits and washable garments.
• Radiation Protective Clothing: Shields from radiation using materials like lead, covering the entire body and sealing gaps for maximum protection.
• Electrical Insulation Protective Clothing: Protects against electrical shocks, made from high-insulation materials and offering heat resistance and durability.
• Biohazard Protective Clothing: Guards against biohazards, constructed from virus and bacteria-proof materials, often worn with protective accessories for full body coverage.

How to Choose Protective Clothing

When selecting protective clothing, consider the specific hazards of the work environment and the level of protection required. Different garments provide varying levels of protection, often with limitations under certain conditions or for limited durations. Understanding these specifications is crucial to ensure adequate safety and health protection in various occupational settings.

What Is a Notifier?

A notifier is a device designed to monitor environmental conditions and alert individuals to potential dangers. Common types of notifiers include fire alarms, smoke detectors, heat sensors, gas leak detectors, water leak detectors, and earthquake sensors. These devices are crucial for early detection of anomalies, helping to prevent or minimize harm to people and property. Notifiers monitoring power abnormalities are also prevalent, detecting issues like power outages, interruptions, or voltage drops, and alerting facility management or personnel through alarms, emails, or phone calls. This article focuses on notifiers that monitor power abnormalities.

Uses of Notifiers

Notifiers monitoring power abnormalities are vital in protecting sensitive equipment in industrial settings, medical facilities, server rooms, and data centers. They ensure quick response in the event of power disruptions, safeguarding against equipment malfunction and data loss. These devices also play a significant role in disaster preparedness, aiding early detection of power issues during earthquakes or natural events, thereby facilitating timely evacuation and safety measures.

Principles of Notifiers

Notifiers monitoring power abnormalities typically detect voltage changes. They convert AC to DC power, supplying it to a detection circuit that includes a comparison circuit for setting a reference voltage. When voltage exceeds this reference, an output signal activates an alarm. Some models also measure AC power frequency, issuing alerts if deviations occur. Detection sensitivity is adjustable, balancing the need for early detection against the risk of false alarms.

How to Choose a Notifier

Selecting the right notifier involves considering the power source type, specific abnormal conditions to be monitored, alarm communication methods, and installation conditions. Factors include the voltage and frequency of the power source, the need for detection of outages, interruptions, or fluctuations, and the preferred method of alarm communication, whether audible, visual, or remote. Durability and environmental resistance are also crucial for ensuring long-term reliable operation, especially in outdoor or harsh environments.

What Is a Spot Cooler?

A spot cooler is a localized air conditioning device that cools air internally and delivers it as focused airflow. Known also as a cooling fan or portable cooler, it differs from conventional air conditioners by targeting specific zones for cooling, offering energy savings and easy installation without construction work. Spot coolers come in various sizes for both domestic and commercial use. Domestic models are compact and versatile, operating on standard 100V household outlets. Commercial models, operating at 200V, provide greater cooling capacity, making them suitable for use in larger spaces like factories or outdoors.

Uses of Spot Cooler

Spot coolers are ideal for areas where traditional air conditioning is impractical or too costly. They are widely used in factories, warehouses, assembly lines, and commercial kitchens, providing localized cooling for workers or specific areas. These coolers are also useful in domestic settings for targeted cooling in garages, pet areas, or during specific activities like cooking or ironing. They can enhance comfort in various scenarios, from factory floors to outdoor events.

Structure of Spot Cooler

Similar to small air conditioners, spot coolers have heat exchangers and compressors. They intake air, cool it, and release it from the front, while expelling hot air from the back. This design focuses cooling on a narrow area, making spot coolers less suitable for large, sealed spaces. They collect water in a tank, requiring disposal when full. Regular filter cleaning is necessary to maintain efficiency.

Types of Spot Coolers

Spot coolers come with additional functionalities like dehumidification, heating, and clothes drying. Multifunctional models can be used throughout the year, providing versatility compared to seasonal appliances. Their portable design allows for reuse in different spaces, offering practicality over multiple fixed air conditioners.

How to Choose a Spot Cooler

When choosing a spot cooler, consider its suitability for open spaces, as they can increase room temperature in enclosed areas. Rain-resistant models are beneficial for outdoor use. Noise level is also a crucial factor, with domestic models averaging around 50dB. Evaporative coolers, using water’s latent heat, offer an eco-friendly alternative with lower noise and power consumption, though they provide different cooling effects compared to traditional spot coolers.

What Is Line Tape?

Line tape, also known as lane marking or floor marking tape, is an adhesive tape used for demarcating areas and creating visual cues in various settings. Made from materials such as vinyl, PVC, or polyester, it is available in a range of colors and widths, making it versatile for different applications.

Uses of Line Tape

Line tape is widely used in industrial, commercial, residential, and other environments. In industrial facilities, it is essential for safety and organization, marking safe zones around equipment or designating storage areas. Retail stores use line tape for aesthetic purposes, creating patterns on floors or demarcating different sections. Its utility extends to enhancing workflow, productivity, and customer satisfaction in various settings.

Principles of Line Tape

Line tape operates on the principle of providing clear and visible markers for safety, organization, and efficiency. Visual cues like bright yellow lines or alternating color patterns help communicate essential information about walkways, restricted zones, storage areas, and workspaces. Proper installation and maintenance are crucial for its effectiveness and durability.

Types of Line Tape

Different types of line tape cater to specific needs. Vinyl line tape is durable and chemical-resistant, ideal for high-traffic industrial use. PVC line tape, known for its flexibility, is great for marking curved or uneven areas. The choice depends on the specific requirements of the environment where the tape will be used.

How to Choose Line Tape

Choosing the right line tape involves considering factors like the surface type, durability, color, width, removability, and cost. Tapes should be selected based on the surface they will adhere to, the expected foot or vehicle traffic, and the need for temporary or permanent markings. Color and width should align with the intended use and safety regulations, and cost should be weighed against long-term effectiveness.

What Is Prepress?

Prepress encompasses the processes involved in preparing materials for printing, including creating printing plates and desktop publishing (DTP). It involves tasks like manuscript planning, text input, page layout, and outputting manuscript films for printing machines. With advancements in DTP, all prepress tasks are now achievable on computers, allowing sophisticated operations such as image import, processing, and page layout refinement.

Prepress has evolved with the proliferation of DTP and image setters, enabling direct plate making from manuscripts without the need for film output. This development has made prepress more efficient and cost-effective, particularly in publishing and commercial printing.

Uses of Prepress

Prepress plays a critical role in determining the quality of printing and binding. It involves standardizing colors for consistent reproduction and ensuring precision in the printed material. Digital prepress, which uses computers for most tasks, has become the dominant method in the industry, streamlining the process and reducing costs and lead times significantly.

Principles of Prepress

In prepress, the primary objective is to prepare a design and layout ready for printing. This stage involves proofreading data corrections, color sample checks, and finalizing the manuscript for metal plate creation and printing. The duration of prepress work varies depending on the readiness of the data and the extent of required revisions.

Structure of Prepress

Printed material production comprises three stages: prepress, press, and post-press. Prepress involves manuscript adjustments, design, character sizing, color tuning, and creating print data. It includes planning content, formatting advertisements or publications, creating images and designs, typesetting, image processing, layout assembly, and final plate completion. The press stage encompasses the actual printing process, while post-press involves finishing tasks like processing, binding, and shipping.

Types of Prepress

Prepress includes photoretouching, a vital image processing technology. Tasks in photoretouching range from cutting and erasing/transplanting parts of images to color conversion, restoration, and composite processing. Color proofing is another crucial aspect, involving outputting color proofs using plate data and digital proofing systems to ensure accuracy and consistency in color standards.

What Is a Soundproof Box?

A soundproof box is a container or room specifically designed to isolate internal sounds and prevent external noises from penetrating. This isolation is achieved using specialized walls and sound-absorbing materials. Soundproof boxes are used in various settings, from music studios and karaoke rooms to industrial and nanotechnology applications.

In nanotechnology, soundproof boxes are particularly vital. They house sensitive equipment like scanning probe microscopes (SPMs), protecting them from external noise and vibrations that could affect measurement accuracy. These boxes are essential for ensuring precise observations and analyses of minute material surfaces.

Uses of Soundproof Boxes

Soundproof boxes are crucial in nanotechnology for housing SPMs, including atomic force microscopy (AFM), scanning tunneling microscopy (STM), and scanning near-field optical microscopy (SNOM), rely on minimal interference for accurate results. Even minor vibrations or sounds can significantly impact these sensitive measurements, making soundproof boxes an indispensable part of the setup.

Principles of Soundproof Boxes

Soundproof boxes in nanotechnology are designed to mitigate both airborne and vibration noises. They utilize sound-absorbing materials and structures to reduce airborne noise. Vibration noises are addressed through vibration isolation plates, anti-vibration mats, and materials on the box’s floor. This combination ensures the highest level of noise and vibration reduction, crucial for the accuracy of SPM measurements.

Structure of Soundproof Boxes

The structure of a soundproof box typically includes outer walls made of materials like metal or aluminum, with layers of sound-absorbing materials for effective noise reduction. The inner walls are also lined with sound-absorbing materials, and some boxes feature a hollow multilayer soundproof structure for enhanced performance. The doors of these boxes are designed with high sealing capability to maximize soundproofing effectiveness, ensuring an optimal environment for sensitive nanotechnology equipment.