Dell 5330dn Service Manual page 32

2.2.2.2 Transfer
It consists of a PTL (Pre-transfer Lamp) and a transfer roller. A PTL sheds light on an OPC drum, lowers an
electric potential of an OPC drum's surface, and improves the efficiency of the transfer.
A transfer roller transfers toner on an OPC drum to the paper.
Life span: Print over 150,000 sheets (In 16~27 )
2.2.2.3 Driver Ass'y
By driving the motor, the system takes power. It consists of a main motor for feeding fuser and duplex
reverse turn, and a deve-motor for a print cartridge.
- Main Motor : DC 24V, Rated RPM : 1604rpm
- Deve Motor : DC 24V, Rated RPM : 1424 rpm
2.2.2.4 Fuser
It is consisted of a heat lamp, heat roller, pressure roller, thermistor and thermostat. It sticks the toner on
a paper by heat and pressure to complete the printing job.
- E-coil Heator : 1,300 Watt 50W
1) Thermostat
When a heat lamp is overheated, a Thermostat cuts off the main power to prevent over-heating.
- Non-Cotact type Thermostat
2) Heat roller
The heat roller transfers the heat from the e-coil to apply a heat on the paper. The surface of a heat roller
is coated with Teflon, so toner does not stick to the surface.
3) Pressure roller
A pressure roller mounted under a heat roller is made of a silicon resin, and the surface also is coated
with Teflon. When a paper passes between a heat roller and a pressure roller, toner adheres to the
surface of a paper permanently.
4) Items for safety
Protecting device for overheating
- 1st protection device: Hardware cuts off when overheated
- 2nd protection device: Software cuts off when overheated
- 3rd protection device: Thermostat cuts off main power.
Safety device
- A fuser power is cut off when a front cover is opened
- Maintain a temperature of fuser cover's surface under 80(C for user, and attach a caution label at
where customer can see easily when customer open a rear cover.
2.2.2.5 LSU (Laser Scanner Unit)
It is the core part of the LBP which switches from the video data received to the controller to the electrostatic
latent image on the OPC drum by controlling laser beam, exposing OPC drum, and turning principle of
polygon mirror. The OPC drum is turned with the paper feeding speed. The /HSYNC signal is created when
the laser beam from LSU reaches the end of the polygon mirror, and the 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 paper. The
one side of the polygon mirror is one line for scanning.
Service Manual
Product spec and feature
2-21