Samsung SCX 4520, SCX-4521F, SCX4720F Operation Instruction & Installation

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4. Summary of Product

This chapter describes the functions and operating principal of the main components.

4.1 Printer Components

4.1.1 Front View

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4.1.2 Rear View

* This wireless network antenna is not supplied with the machine. It is an option that must be purchased and

installed separately. (Option Function)

** The network port is not fitted as standard on the machine. You can purchase an optional Network Card and

install it separately.

*** If your country has a different telephone connection system, this socket may be blocked.

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4.1.3 Control Panel (SCX-4720F)

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Control Panel (SCX-4520)

Adjusts the brightness of the documents for the current copy job.

Selects the document type for the current copy job.

Allows you to access a list of your PC software programs that an image can be scanned to.

S C A N

You must create the scan list using the Samsung software (Printer Setting Utility) provided with this machine. Also allows you to scan and save documents in a USB flash drive, and manage it when it is inserted into the USB port of your machine. See User Guide Chapter 10, Installing a USB Flash Drive.

Displays the current status and prompts during an operation.

Turns on when the toner cartridge is empty.

Uses to scroll through the available options for the selected menu item.

Confirms the selection on the display.

Enters Menu mode and scrolls through the menus available.

Sends you back to the upper menu level.

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Stops an operation at any time. In Standby mode, clears/cancels the copy options, such as the darkness, the document type setting, the copy size, and the number of copies.

Starts a job.

Selects the number of copies.

Allows you to use special copy features, such as Clone, Collation, Auto Fit, 2Sides on 1pg, 2/ 4 Up (multiple pages on a sheet), and Poster copying.

Makes a copy smaller or larger than the original.

Allows you to save on toner by using less toner to print a document.

Allows you to directly print files stored on a USB flash drive when it is inserted into the USB port in front of your machine.

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4.2 System Layout

The SCX-4720F/4520 is roughly made up Main Control part, Operation Panel part, Scanner part, Line Interface part and Power part. Each Part is separated Module which focus on common and standard design of different kind products. main control part adopting Fax & LBP Printer exclusive Controller is composed of 2 CPU and 1 Board. Scanner part is composed of ADF and Platen and is connected with Main by Harness.

4.2.1 Feeding section

There is a universal cassette which automatically loads paper and the manual feed which supplies paper single sheet at a time. The cassette has a friction pad which separates paper to ensure single sheet feeding, and it has a sensor, which checks when the paper tray is empty.

- Feeding Method: Universal Cassette Type

- Feeding Standard: Center Loading

- Feeding Capacity: Cassette-250 sheets (75g/m2, 20lb paper standard) Manual 1 sheet (Paper, OHP, Envelop, etc.)

- Paper detecting sensor: Photo sensor

- Paper size sensor: None

4.2.2 Transfer Ass’y

This consists of the PTL (pre-transfer lamp) and the Transfer Roller. The PTL shines a light onto the OPC drum. This lowers the charge on the drum’s surface and improves transfer efficiency. The transfer roller transfers toner from the OPC drum surface to the paper.

- Life expectancy: Over 60,000 sheets (at 15~30°C)

4.2.3 Driver Ass’y

- Gear driven power unit. The motor supplies power to the paper feed unit, the fuser unit, and the toner cartridge.

4.2.4 Fixing Part(Fuser)

- The fuser consists of the Heat Lamp, Heat Roller, Pressure Roller, Thermistor, and Thermostat. It fixes toner to the paper using pressure and heat to complete the printing job.

4.2.4.1 Temperature-Intercepting Device (Thermostat)

The thermostat is a temperature sensing device, which cuts off the power to the heat lamp to prevent overheating fire when the heat lamp or heat roller overheats.

4.2.4.2 Temperature Detecting Sensor (Thermistor)

The Thermistor detects the surface temperature of the heat roller, this information is sent to the main processor which uses this information to regulate the temperature of the heat roller.

4.2.4.3 Heat Roller

The surface of the Heat Roller is heated by the Heat Lamp. As the paper passes between the Heat and Pressure rollers the toner is melted and fixed permanently to the paper. The surface of the roller is coated with Teflon. This ensures that toner does not adhere to the roller surface.

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4.2.4.4 Pressure roller

The Pressure Roller mounted under the heat roller, it is made of a silicon resin, and the surface of the roller is coated with Teflon. This ensures that toner does not adhere to the roller surface.

4.2.4.5 Safety Features

• To prevent overheating

- 1st protection device: Hardware cuts off when overheated

- 2nd protection device: Software cuts off when overheated

- 3rd protection device: Thermostat cuts off mains power to the lamp.

• Safety device

- Fuser power is cut off when the front cover is opened

- LSU power is cut off when the front cover is opened

- The temperature of the fuser cover's surface is maintained at less than 80ºC to protect the user and a caution label is attached where the customer can see it easily when the rear cover is opened.

4.2.5 Scanner

This image is read using a photosensitive sensor. It consists of a CCD module, Connection board, ADF board, AFE (Analog Front End), Image Processor (Located in CPU), platen glass and ADF mechanism.

• CCD Module Specification

1.Resolution: 600dpi/A4

2.Maximum scan wide: 8.5”

3.Color filter: Red, Green, Blue

4.Output channel: 3 channels (R, G, B)

5.Effective pixel: 5,400 pixel *3

6.Voltage: 24V & 5V

7.Pre-heating time: Maximum 30 seconds (70% of light output reached)

8.The life span of a lamp: 30,000 hours (25oC)

• Image Processor Specification

1.Operating frequency: 66MHz

2.Image sensor interface: 200/300/600 dpi CIS or CCD

3.Line time: Copy, FAX, Binary (Lineart, Halftone) PC Scan: 1.5ms/Line Color PC Scan (Grey, 256 Color, True Color): 4.5ms/Line

4.A/D conversion: 10bit conversion

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4.2.6 LSU (Laser Scanner Unit)

This is the core of the laser printer. It converts the video data received from the computer into an electrostatic latent image on the surface of the OPC drum. This is achieved by controlling the laser beam and exposing the surface of the OPC drum to the laser light. Arotating polygon mirror reflects the laser light onto the OPC and each side of the mirror is one scan line. The OPC drum turns as the paper feeds to scan the image down the page.

The /HSYNC signal is created when the laser beam from LSU reaches the end of the polygon mirror and this signal is sent to the controller. The controller detects the /HSYNC signal to adjust the vertical line of the image on paper. In other words after the /HSYNC signal is detected the image data is sent to the LSU to adjust the left margin on the paper.

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