月: 2023年7月

What Is a 6 Wheel Trolley?

A 6 Wheel Trolley is a cart with six wheels.

The height of the hand-held fence is higher than that of a regular 4-wheel cart, and the bottom of the cart is narrower, but often long and narrow. Hand-held fences are available in one- and two-wheel types, and are shaped to be easier to pass through narrow aisles than 4-wheel carts.

The load capacity is larger than that of a 4 Wheel Trolley, about 300 kg. 6 Wheel Trolleys are equipped with casters, but when nothing is loaded on them, the casters in the middle and at one end touch the floor. When loaded with a heavy load, all casters touch the floor.

Uses of 6 Wheel Trolleys

The main uses of 6 Wheel Trolleys are as follows:

1. Luggage Transportation

Trolleys are widely used as tools for efficiently transporting luggage and heavy boxes. They are useful for transporting luggage in hotels, warehouses, stores, etc.

2. Industry and Manufacturing

Trolleys are used to transport equipment and parts in factories and manufacturing sites. They are used to move large machinery and carry parts on assembly lines.

3. Construction

Trolleys are used to move heavy materials and tools at construction sites. They are suitable for carrying concrete blocks, steel frames, tools, etc.

4. Garden and Agriculture

In addition to transporting goods, Trolleys are also used for work in gardens and farms. They are useful for transporting soil, fertilizers, agricultural products, etc.

5. Lawn Mowers and Gardening Equipment

They are sometimes used to transport and store large lawn mowers and gardening equipment.

6. Commercial and Events

Trolleys are used to transport equipment and materials at trade shows and events.

7. Medical Facilities

6 Wheel Trolleys are sometimes used in hospitals and nursing homes to transport patients and medical equipment. 6 Wheel Trolleys are longer and narrower than 4 Wheel Trolleys, making them easier to pass through doors and turn back and forth.

They are equipped with high, hand-held rails so they can be stacked with cargo. They are used in warehouses and factories as well as in narrow bookstores to transport heavy books and other items.

Principle of the 6 Wheel Trolley

The main feature of 6 Wheel Trolleys is that they are more stable than 4 Wheel Trolleys and can carry more load. They also have excellent straightness. Products with the middle caster grounded and the caster at one end floating can be rotated freely and are easy to maneuver.

A locking mechanism is provided under the handrail, and the wheels stop when you step on the lock with your foot. All casters are secured, so they are very safe. 4 Wheel Trolleys have a braking mechanism, but 6 Wheel Trolleys have a chain linkage that allows them to stop securely even on slopes.

Many products cannot be folded, but they can be nested, allowing the carts to be stored together to save space. The 73cm width, which is the standard size for doors in Japan, does not allow a 4 Wheel Trolley to pass through with a large load, but a 6 Wheel Trolley can pass through with a load.

The intermediate shelf, which is an accessory, further increases the strength of the cart and allows it to carry a large number of loads. However, the disadvantage of 6 Wheel Trolleys is that the casters on one end are floating, so they make a lot of clattering noise when loaded and moved, which can be more noisy than a 4 Wheel Trolley.

How to Select a 6 Wheel Trolley

The basic rule for selecting a Trolley is to choose a Trolley that is appropriate for the size and weight of the load to be carried. The load capacity of the cart is an important indicator and should not exceed the weight of the cargo to be transported.

The type and number of wheels should also be selected according to the environment and terrain in which the load is to be carried. Large rubber wheels are suitable for hard floor surfaces, while larger pneumatic wheels are useful on uneven terrain or in environments with many obstacles. In addition, the shape of the pedestal should match the shape of the load to be transported.

If a flat base is required, a platform cart is suitable, while a box-type cart is suitable for cubic-shaped loads. The durability of the cart is also important for long-term use. Especially for industrial applications, a sturdy cart is necessary. In addition, handles for operating the carts should be of appropriate height and shape.

What Is a System Reset IC?

System Reset IC is a semiconductor device that monitors supply voltage and supplies a reset signal to the microcontroller.

When a voltage below the normal operating voltage range is applied to a microcontroller, the microcontroller is unable to operate according to the requirements of the control program. As a result, the internal data is destroyed and the electronic equipment cannot operate as originally expected, which may lead to a fatal situation.

The purpose of using System Reset ICs is to prevent such abnormal behavior of the microcontroller program.

Usage of System Reset ICs

The System Reset IC monitors the power supply voltage provided to the microcontroller and connects the output signal of the Reset IC to the microcontroller’s reset input signal terminal for use.

Microcontrollers are used in many devices, including information equipment such as PCs, smartphones, and tablet terminals; general home appliances such as refrigerators, air conditioners, and washing machines; AV equipment such as TVs, BD recorders, and audio equipment; automotive equipment such as cars and motorcycles; office equipment such as printers and scanners; and professional equipment such as measuring instruments and various test equipment. System Reset ICs are also used in many other types of equipment.

Principle of System Reset IC

Generally, an IC consists of three pins: a supply voltage pin (VDD), a GND pin, and a reset signal output pin (OUT).

The IC has a voltage detection function, and when the voltage input to VDD falls below a predetermined voltage, the microcontroller is reset to ensure stable System Reset IC operation.

How to Select a System Reset IC

System Reset ICs reset the microcontroller when the voltage of VDD is lower than the detection voltage, and release the reset when the voltage of VDD is higher than the detection voltage. It is important to select an IC that matches the voltage range of the microcontroller to be used.

Types of System Reset ICs

1. Output Type

There are two types of output types for the OUT pin of System Reset ICs: the Nch open drain type and the CMOS type. The Nch open drain type requires an external pull-up resistor on the OUT pin, while the CMOS type does not require an external pull-up resistor.

For the Nch open drain type, elements other than the microcontroller can be connected, but for the CMOC type, the IC and microcontroller must be connected one-to-one.

2. WDT (Watch Dog Timer) Type

In addition to products that simply detect a predetermined voltage and generate a system reset, there are also types that incorporate a WDT (Watch Dog Timer).

In addition to monitoring the voltage to generate a reset to the system, the built-in WDT also generates a reset to the microcontroller in case of abnormal operation of the microcontroller.

The WDT function is used by connecting the WDT signal output from the microcontroller to the reset IC. The WDT signal output from the microcontroller is a pulse signal with a constant frequency when the microcontroller is operating normally. However, if the microcontroller becomes unstable, the WDT signal will not have a constant frequency.

The reset IC monitors the frequency of the WDT signal and resets the microcontroller if the frequency is abnormal.

3. Type With Delay Timer

A type with a built-in delay timer is also available. This function releases the reset to the microcontroller after a set period of time has elapsed. The reset can be released stably even when excessive voltage fluctuations occur.

What Is a Pulse Logger?

A Pulse Logger is an instrument or device that records a time series of signals that occur rapidly over a short period of time.

By digitally converting signals sent from sensors usually connected to a detector, it can automatically record them as data over time. It is used to analyze events.

Therefore, it is not used alone. It can be incorporated to count the number of signals per unit time sent from a rotating counter, such as a flow meter or an anemometer, to determine its volume and speed.

Uses of Pulse Loggers

Since pulse signals output according to speed or quantity can be digitally converted and recorded, a unit conversion device and a detection device can be incorporated according to the purpose of measurement. It is possible to calculate water, gas, and electricity usage, rainfall, and wind speed.

Pulse Loggers only function to count pulse signals in a time series, but they have less deterioration over time than analog loggers and have excellent preservation properties. Due to their continuous and long-term use, pulse loggers are also used for various environmental measurements at research institutes.

Principle of Pulse Logger

1. Conversion to Digital Signal

Analog signal outputs such as contact signals and DC voltage signals generated by a revolution counter are converted to digital signals through a signal converter and counted. The counts are then continuously recorded in data memory at set time intervals.

By multiplying the number of counts per hour by a factor that matches the measurement objective, the recorded data can be calculated according to the measurement unit. Pulses are not time-stamped, but are recorded in data memory based on the time they occur.

2. Pulse Signal Measurement

If the frequency is f (Hz) and the period is T (sec), the relationship is f = 1/T. Therefore, the data to be measured can be obtained by measuring either of them. Pulse Logger has the following two types of pulse measurement methods:

Direct Method
In the direct method, a fixed time is set for the gate pulse, and the number of pulses to be measured within the gate pulse is counted. The direct method directly measures frequency.

Reciprocal Method
In the reciprocal method, the pulse to be measured is the gate pulse, and a clock signal set to a specific frequency is output. The signal period is obtained by measuring the number of clock signal pulses relative to the gate pulse. Therefore, the reciprocal method measures frequency from the reciprocal of the period.

How to Select a Pulse Logger

1. Difference in the Number of Counts

The method used for measurement is the direct method using frequency (Hz) if the number of counts of pulse signals output per second is large. When the number of counts is small, the reciprocal method is often used, which uses a period based on the length of time per round trip of the pulse signal that is output repeatedly.

2. Difference of Methods

For measuring instruments with short-period time lengths, the number of data points increases and accurate values can be recorded, but it is difficult to recognize short-period data that exceeds the sensitivity. Conversely, if the time length is set to long-period, the instrument cannot measure pulse width or detect short-period pulses because there is no pulse signal within the set measurement time.

Therefore, considering whether the purpose of measurement is short-period or long-period, it is required to select a device with a measurement method that matches the pulse signal strength, data collection period, and the amount of pulse counts, and to adjust the set value.

Other Information on Pulse Loggers

Examples of Pulse Logger Applications

One example of Pulse Logger use is for measuring the rotation speed of copier rollers. The purpose is to measure the number of roller rotations for operation verification in research and development.

By using a temperature measurement unit and acceleration measurement unit at the same time, it is also possible to inspect radiated heat and operation defects of each part. Measurement data can be transferred to a PC via a network for simultaneous measurement and verification.

What Is an Acceleration Logger?

An Acceleration Logger is a device or system that records and measures the acceleration of an object or device.

It is a device that combines an acceleration sensor and a data logging function to measure and record acceleration. The latest products are capable of measuring acceleration up to 400G, and are now mostly compact and lightweight.

This makes it possible to measure the acceleration of rotating objects, the human body, and small animals, which have been difficult to measure in the past. In addition, they support high-speed sampling and are equipped with a large-capacity memory, which broadens the range of measurement.

Applications of Acceleration Loggers

Acceleration Loggers are used in a wide range of industries because of their compact size and ability to measure a wide range of frequencies. They are used to measure vibration in automobiles, logistics, transportation, equipment, sports, and other applications.

Most of them are small and consist of a sensor and a logger in one unit, enabling measurement in places where it has been impossible to install them in the past. They are used for product evaluation tests such as drop tests and shock tests, and for detecting head, hand, and foot movements of the human body.

Taking advantage of Acceleration Logger, it is possible to measure objects that could not be measured with conventional sensors and loggers.

Principle of Acceleration Loggers

Acceleration Loggers are mainly composed of an acceleration sensor, flash memory, CPU, and battery, although each manufacturer is different. Acceleration sensors are mostly 3-axis type sensors, and a single Acceleration Logger can measure acceleration in 3 axes at one time. Furthermore, the measurement range can be up to 400G, making it suitable for drop tests and shock tests.

In addition, recent Acceleration Loggers are lightweight and do not affect changes to the natural frequency of the object being measured. Their small size also makes it possible to measure the motion, tilt, and vibration of people and small animals. By connecting the main body of Acceleration Logger to a PC with a USB cable, it is possible to supply an external power source, monitor acceleration in real time, set various measurement conditions, and download recorded data.

Each electronic component of Acceleration Logger is in standby mode until a command to measure is received, and data is recorded in flash memory. Therefore, data is not lost even if the power is turned off.

How to Select Acceleration Logger

1. Purpose and Measurement Range

It is necessary to consider the purpose of using Acceleration Logger and the range you wish to measure. Acceleration Loggers are used in a variety of applications, and the specifications required will vary depending on the type of acceleration to be measured. First, clarify the intended use, such as in what situations, places, and time periods.

2. Measurement Accuracy

Accuracy of Acceleration Logger is an important factor. If you need particularly high precision measurement, you need to choose a product that can measure more precisely; narrowing the range from 400G to 200G, for example, can reduce the cost.

3. Data Recording Capacity

The amount of data a logger can record is also important. If you are taking measurements for long periods of time or need to record data frequently, it is important to select a product capable of recording large amounts of data.

4. Battery Life

The battery life of a logger should be selected based on the measurement period. If the measurement period is long or the logger is to be used outdoors, a battery that can operate for a long time is necessary. Longer life is not necessarily better, but the cost will be higher, so it is best to select the optimum duration for the application.

5. Operability and Data Acquisition Method

Check to see if the Acceleration Logger is easy to use. The method of data acquisition, such as USB connection or wireless communication, is also important. Depending on the application, there may be cases where it is handled by you alone, or by several people, or by workers who are not familiar with it. Consider how the product will be used and select a product that is easy to operate according to the user level. 

6. Durability and Water Resistance

Acceleration Loggers are often used in the field, so choosing a product that is durable and waterproof will ensure long use. Even if the battery is preserved, damage to the device itself or flooding can render it unusable, so it is necessary to be clear about where the logger will be used.

What Is a Two-Fluid Nozzle?

Two-Fluid Nozzles are special nozzles built into equipment used in industrial applications.

These nozzles are designed to mix and inject two different fluids. The principle of the Two-Fluid Nozzle itself, which is incorporated into industrial equipment, is also found in rocket engines, but unlike these high thrust applications, it is generally applied to industrial processes and equipment.

Two-Fluid Nozzles can achieve the required process or treatment by appropriately controlling the fluid supply, pressure, and velocity. For example, in atomizing nozzles, it is important to control the spray angle, particle size, and spray pattern of the liquid. Also, in processes involving reactions, it is necessary to precisely control the mixing ratio of fluids and reaction conditions.

Applications of Two-Fluid Nozzles

The main applications of Two-Fluid Nozzles are as follows:

1. Atomizing and Dispensing

By mixing liquid and gas and atomizing them into a fine mist, paints and coatings can be applied evenly to surfaces. This technology is widely used in painting and anticorrosion coatings.

2. Cooling and Humidification

Two-Fluid Nozzles can be used to cool ambient air by atomizing the liquid into a fine mist. It can also be used as a humidifier to regulate the humidity in the air.

3. Cleaning and Disinfection

By spraying liquid through a nozzle, surfaces and spaces can be kept clean and free of microorganisms and bacteria. It is used in connection with cleaning and sanitation.

4. Chemical Reaction

Two different liquids may be mixed in the nozzle to promote a chemical reaction. This is utilized for specific reaction processes or synthesis.

5. Combustion

Two-Fluid Nozzles may be used to mix and burn fuels and oxidizers. This is an application found in industrial processes and burners that utilize thermal energy.

6. Separation

Two different phases (e.g., gas and liquid) may be separated through a nozzle. This method is intended to remove or separate certain components.

7. Agriculture

Two-Fluid Nozzles are sometimes used to properly inject liquids or gases, for example, in agricultural sprayers.

Principle of Two-Fluid Nozzle

The principle of Two-Fluid Nozzles is to mix two different fluids to achieve a desired process. The general Two-Fluid Nozzle principle is as follows:

1. Fluid Supply

Two-Fluid Nozzles typically draw two different fluids from separate feed paths. Each fluid is fed into the nozzle independently.

2. Mixing

Inside the Two-Fluid Nozzle, the two fluids are mixed. This mixing is accomplished by the nozzle’s internal structure. The area where the fluids are mixed can be adjusted by controlling the velocity, pressure, etc. of the fluids.

3. Injection

The nozzle injects the mixed fluid. The speed and direction of the injected fluid are determined by the nozzle geometry and fluid supply.

4. Application

The injected mixed fluid is used according to the desired process. For example, in an atomizing nozzle, the fluid is sprayed onto tiny particles for application or cooling. In the case of chemical reactions, two fluids are mixed to facilitate a reaction.

A key element is the design and control of the Two-Fluid Nozzle. Proper adjustment of the fluid supply, pressure, velocity, and nozzle geometry can improve mixing uniformity and efficiency. Two-Fluid Nozzle materials are also chosen to be resistant to the properties of the fluid being injected.

Types of Two-Fluid Nozzles

Common types of Two-Fluid Nozzles are as follows:

1. Atomizing Nozzle (Spray Nozzle)

This nozzle mixes liquid and gas and atomizes them into a fine mist. They are used for dispensing, cooling, humidifying, disinfecting, air freshener dispensing, etc.

2. Mixing Nozzle

These nozzles are used to mix two different liquids to obtain a homogeneous mixture. It is used in chemical reaction processes and synthetic reactions.

3. Separating Nozzle

Separation nozzles separate two different phases (e.g. gas and liquid) and are used to remove or separate specific components.

4. Gas Ejector

A nozzle that injects a high-velocity gas and draws a low velocity fluid around it to mix it. It is used for suction and mixing of gases.

5. Injector

This is a nozzle that injects one fluid and draws and mixes another fluid with it. It is used in agricultural sprayers.

6. Jet Ejector

A jet ejector is a nozzle that injects a high-speed fluid, thereby suctioning and mixing a low-speed fluid. Also called an ejector nozzle, it is used for mixing liquids and gases.

7. Shield Gas Nozzle

A nozzle through which gas flows to prevent reactions during welding and cutting. Used to prevent highly reactive environments during certain processes.

What Is a Photomicrosensor?

Photomicrosensors are small optical sensors with built-in amplifiers.

It can detect the presence or absence of an object and its position using light. Photomicrosensors are available in reflective and transmissive types, and are called “photointerrupters” and “photo-reflectors,” respectively. These sensors are mainly used in various familiar products for built-in devices.

Applications of Photomicrosensors

Photomicrosensors are classified into four types depending on the object to be detected.

1. Reflective Type

This type of sensor uses a reflection of light. They are used for detecting the presence of paper in a printer and for simple barcode reading. 

2. Transmissive Type

This simple sensor detects objects by light passing through a slit, and is used to detect IC cards, train tickets, etc.

3. Separate Type

This type of sensor allows the distance between the light-emitting and light-receiving parts to be adjusted by moving the light-emitting part. This type of sensor is used to detect the passage of an object when a person buys a product from a vending machine or wins a prize in a game machine.

4. Actuator Type

This is a sensor that combines levers called actuators. It is used in ticket vending machines and vending machines to detect the passage of banknotes.

Principle of Photomicrosensors

The principle of photomicrosensors varies depending on the type. It is important to select the most suitable one of these sensors depending on the object to be detected and the location where it is used.

1. Reflective Type

The reflective type has a structure in which the light-emitting element and the light-receiving element are installed in parallel. Light emitted from the light emitter hits an object, is reflected, and is received by the light receiver.

The object is detected by this reflected light. Although it is easy to install, the disadvantage is that the objects to be detected and the distance to be detected are limited. 

2. Transmissive Type

Transmissive sensors have a structure in which the light emitting element and the light receiving element are installed facing each other. Light emitted from the light emitting element is directly received by the light receiving element. If there is no object, the light is received as it is, but if there is an object, the light does not reach it.

It is simple and does not require alignment of the optical axis, but its disadvantage is that the size of the object to be examined is limited.

3. Detached Type

Separated type has a structure in which the light emitting and light receiving parts face each other in a separated state. Since the light emitting and light receiving elements are separated, the position can be freely determined, but the disadvantage is that the optical axes must be aligned.

4. Actuator Type

The actuator type has a structure that combines a see-through sensor and a lever that rotates. By using a lever to block light, even objects that allow light to penetrate can be detected. However, the disadvantage is that the parts around the lever have a limited life span, limiting the period of use.

Other Information on Photomicrosensors

Photomicrosensor Circuit Design

Important characteristics to consider when designing are the photocurrent and resistance, which indicate how much output is available from the amount of forward current. The key point when designing is to consider and select the optimum level of forward current before designing the limiting resistance value. Also, if a reverse voltage is applied, design a diode in reverse parallel with the LED.

By designing the worst-case value, it is possible to ensure normal operation even when the characteristics are biased toward the worse side in terms of function. While considering the above points, it is necessary to supply an appropriate level of current externally. Designing while considering how much forward current is required for the photosensitive side to operate will ensure normal operation.

In the design of phototransistor output type, the temperature dependence of dark current and photocurrent must be taken into consideration. When detecting an object with high transmittance or an object smaller than the shape and dimensions of the surface to emit and receive light, the photocurrent with and without the object must be measured and their ratio must be calculated.

What Is Millimeter Wave Radar Evaluation Kit?

Millimeter wave radar evaluation kit is a device that uses millimeter wave band radio waves to measure the positional relationship with an evaluation object. It can measure not only distance to an object but also angle and relative velocity with high accuracy.

The use of the millimeter wave band offers the following advantages:

• Resistant to Environmental Changes
  Because it uses radio waves, it is resistant to environmental changes. Measurements can be made without being affected by weather or illumination.
• Excellent Resolution
  Resolution improves in higher frequency ranges, such as 77 GHz. It can distinguish and recognize multiple objects even if they are located in close proximity to each other.

Applications of the Millimeter Wave Radar Evaluation Kit

An example of where the millimeter wave radar evaluation kit is used is in the automatic detection of automobiles.

Compared to trains and airplanes, automobiles are vehicles that are more prone to collisions with other objects. Object detection systems are being developed to assist in avoiding collisions.

While low-frequency radar has been used in the past, the use of high-resolution millimeter-wave radar is rapidly advancing. Legislation on the use of millimeter-wave radar is being developed around the world.

In recent years, the application of millimeter-wave radar is being considered not only for automobiles but also for drones.

Principle of Millimeter Wave Radar Evaluation Kits

Detection of objects is made possible by sensing radio waves in the millimeter wave band.

Radio waves have the characteristics of waves and travel through the air at a specific vibration. The specific frequency of oscillation is called frequency, and they are classified according to their frequency. Millimeter wave bands are waves with frequencies between 30 GHz and 300 Hz.

The higher the frequency of the wave, the stronger the straightness. The higher the frequency, the stronger the straightness, which means that information is less impaired, and thus a large amount of information can be transmitted faster. In addition, the short wavelength of the millimeter wave band enables highly accurate sensing even in smaller sizes.

The millimeter wave band has been used in automobiles and other vehicles, but in recent years it has also been introduced in the field of communications, such as smartphones, where it is being discussed as 5G and can transmit information at higher speeds than 4G.

However, there are challenges to the introduction of millimeter wave bands in the telecommunications field. One of them is the maintenance of base stations. The shorter wavelength of the millimeter wave band shortens the distance that radio waves can reach. The solution to this problem is to increase the number of base stations, but this may take time due to cost issues.

What Is a Liquid Level Sensor?

A liquid level sensor is a sensor that can determine the type of liquid flowing in a container or piping. It can detect when liquid flow in a pipe is interrupted or when another liquid is mixed in.

It can discriminate between two types of liquids that have been measured in advance. The sensor can determine which liquid is flowing in the piping, whether it is mixed in or not, or whether neither is flowing in the piping.

Liquids, such as tap water, distilled water, alcohol, chemicals, cleaning solutions, and oil, can be detected. Some models are under development, and future developments are expected.

Applications of Liquid Level Sensors

Liquid level sensors are small and easy to install, so they are installed on pipes and other equipment in factories. In food factories and other places where safety is important, it is critical to determine whether a liquid leaking from a pipe is water or a chemical, so some factories are installing liquid type determination sensors to help with maintenance.

Although there are only some liquid level sensors on the market today, they are needed in many areas, and we can expect to see more examples of their use in the future as further development progresses.

Principle of Liquid Level Sensors

Liquid level sensors are new sensors, and a type that uses the difference in dielectric constant of liquids is currently on the market. Another type, currently under development, uses optical fibers.

In the type that detects differences in the dielectric constant of a liquid, the sensor part is immersed in the liquid and the dielectric constant is measured. It is possible to determine the type of liquid, determine the state of emptiness, and detect leaks. In addition to tap water, alcohol, various chemical solutions, and oil, this type can also be used for highly viscous liquids such as paints and adhesives.

The optical fiber type can be used for measurement in explosion-proof areas by using a bend-resistant optical fiber for the detection section. This type can also be used to measure liquids such as oil and gasoline, which can ignite.

Another type of liquid identification device that is still in the research and development stage but is being considered is one that determines the type of liquid based on the rate at which the temperature of the liquid rises. This device consists of a liquid type sensing section with a heating element and a temperature sensing element, and a liquid temperature sensing section. A single pulse voltage is applied to the liquid type sensing section to generate heat, and the liquid temperature is measured at the liquid temperature sensing section. The type of liquid can be determined from the change in liquid temperature before the pulse voltage is applied and after a certain period has elapsed after the voltage is applied.

What Is a Clean Locker?

A Clean Locker is a locker used to maintain a clean room environment.

Clean rooms are special spaces where particulates and microorganisms are strictly controlled, and are mainly used in semiconductor manufacturing, biopharmaceutical manufacturing, aerospace industry, and optical equipment manufacturing.

Uses of Clean Locker

When entering and exiting clean rooms, there are usually special procedures and strict clothing regulations to prevent outside contaminants. Reasons include the need to control microscopic particles and microorganisms in clean rooms in order to maintain the quality of products and materials.

In addition, workers wear special gowns (clean suits), masks, and gloves and use a special “clean room entry” to remove particles and microorganisms before entering the work area. Clean Lockers are installed in the Clean Room Entry and are responsible for removing sweat and secretions from the clean suits used in the clean room and keeping them clean.

Basically, workers change into the clean suits stored in the Clean Locker before entering the clean room, and upon completing their work, they return the clean suits to the Clean Locker. This minimizes the impact of contaminants emitted by workers. The main applications by industry are as follows:

1. Clean Rooms in Laboratories and Factories

Used to protect people and goods from contamination when working in clean rooms.

2. Pharmaceutical Plants and Medical Institutions

Used to maintain cleanliness when manufacturing, handling, or adjusting drugs or medical devices.

3. Food Processing Industry

Clean Lockers are used in food production processes to meet hygiene standards.

4. Laboratories in Research Facilities and Hospitals

Clean Lockers are used to store laboratory materials and equipment to prevent infection and increase the reliability of test results.

5. Semiconductor Manufacturing

In the manufacturing process of fine semiconductors, workers are placed in clean rooms to prevent the ingress of particulate matter, and Clean Lockers are used to control clothing and equipment.

Principle of Clean Locker

The main principles of Clean Lockers used in clean rooms are:

1. Physical Isolation

Clean Lockers are hermetically sealed and constructed to exclude external contamination.

2. Hygiene Control

Clean Locker provides a sanitary space for workers to store their clothing and the belongings they bring in. In Clean Locker, ozone decomposition, ammonia decomposition, and ultraviolet decomposition are used to decompose secretions on clean suits.

3. Pressure Control

The air pressure inside a clean room is generally kept higher than that outside. Clean Lockers, as part of this pressure control, are also built with a higher pressure than the air pressure inside the clean room. This keeps outside contaminants from entering the clean room as workers pass through clean room entries.

4. Air Filtering

Clean Lockers filter the air inside to keep it clean. Typically, HEPA (High Efficiency Particulate Arresting) or ULPA (Ultra High Efficiency Particulate Arresting) filters are used, capturing more than 99.97% of particulates.

Types of Clean Lockers

The main types of Clean Lockers used in clean rooms are as follows:

1. Garment Storage Lockers

This Clean Locker is mainly used for storing clean suits. It has ozone decomposition and other functions to decompose secretions attached to clean suits.

2. Lockers for Storing Personal Belongings

These lockers are used to store personal belongings (e.g., cell phones, wallets, etc.) that workers bring into the Clean Locker.

3. Lockers for Storing Equipment and Parts

These lockers are used to store equipment, parts, tools, etc. used in the Clean Locker.

4. Lockers for Storing Contaminated Materials

These lockers are used to store gowns, masks, used equipment, etc. that have been used in the Clean Locker but can no longer be kept clean.

What Is an Oil Cooler?

An oil cooler is a device that maintains the proper temperature of oil used in machinery.

While a device that regulates the temperature of air is called an “air conditioner,” an oil cooler, as the name suggests, controls the temperature of oil. The general structure is not much different from that of an air conditioner, which performs heat treatment through refrigerant gas.

Motor and bearing parts of a machine rotating at high speed generate heat, which may cause unexpected breakdowns or malfunctions. Oil coolers can efficiently remove heat from machines and thus have the ability to support the stable operation of machines.

Uses of Oil Coolers

Oil coolers are often used in machine tools such as machining centers and CNC lathes, which require high precision.

When a spindle rotates at high speed, thermal displacement occurs, adversely affecting machining accuracy. Therefore, by cooling the temperature of the oil used with oil coolers, thermal displacement can be minimized and stable continuous machining can be achieved.

Oil coolers can also be used when production sites using machine tools have problems, such as inconsistent machining accuracy or yield rates.

Principle of Oil Coolers

A typical oil cooler consists of a compressor that compresses air, a condenser, a decompression mechanism, and an evaporator.

• Compressor
  In the compressor, refrigerant gas is subjected to high pressure, resulting in high temperature and high pressure.
• Condenser
  Refrigerant gas under high pressure in the compressor is cooled and condensed by air in the atmosphere, changing it into a liquid.
• Pressure Reducing Mechanism
  The high-temperature, high-pressure liquid is depressurized to a liquid that is easy to evaporate.
• Evaporator
  The liquid produced via the decompression mechanism is brought into contact with machine oil. The liquid then removes heat from the oil and evaporates, becoming a low-temperature, low-pressure gas. This phenomenon is called heat of vaporization and helps cool any substance.

Some of them are also equipped with inverters, while others are not. Without an inverter, temperature control can only be controlled by turning the operation on and off, resulting in a large error from the set temperature. If you want to control oil temperature with higher precision, it is common to choose one with an inverter.

Other Information on Oil Coolers

1. Benefits of Oil Coolers

The primary role of oil coolers is to keep the engine oil at the proper temperature. Engine oil is formulated to perform best at temperatures between 80-100℃.

Cooling the engine oil with oil coolers provides a variety of benefits. The most important effect is to maintain lubricity. Automobiles are made up of a combination of various metal parts such as gears, bearings, and sliding bearings called bushings.

Also, in an engine, the piston slides through the piston chamber. To reduce friction between these parts, oil is essential. By keeping the temperature of the oil in the proper range with oil coolers, the sliding resistance between parts is reduced and the machine can continue to operate normally.

Especially in the case of engines, as output increases, heat from exhaust gases, combustion chambers, and cylinder walls causes the engine oil temperature to rise. Therefore, the temperature is regulated using the power of cooling water. Note that water-cooled oil coolers can prevent the engine oil temperature from dropping too low compared to other oil coolers. This is because the coolant never gets lower than room temperature.

2. Performance Requirements for Oil Coolers

While sufficient cooling capacity is required for automotive oil coolers, there are various other requirements. First, they must be compact and lightweight. Since automobiles are required to have a large occupant space, components that fit inside the engine compartment must always be compact. Lightweight is also an important requirement in terms of fuel efficiency.

Another requirement is that the oil flow resistance must not be too large. If the oil flow resistance is too large, the amount of oil circulating will be reduced and the cooling capacity will also decrease. Also, in a low-temperature environment, the oil needs to warm up quickly. To warm up the oil quickly at low temperatures, it can be said that oil flow resistance is an important requirement.