Text preview for : chap05.pdf part of HP Designjet This is the service manual for designjet models 250,330, and 350C.
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Functional Overview
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Introduction
The HP DesignJet 330 and 350C follow on from and replace the DesignJet 230 and 250C. The HP DesignJet 230 and 250C originally replaced the DesignJet 220 but are now no longer produced. The HP DesignJet 330 and 350C (like the DesignJet 230 and 250C) have inherited much of the system architecture and features of the DesignJet 220. Their writing system, however, is based on that of the DesignJet 650C. This chapter describes only the main features new to the DesignJet 230 and 250C and DesignJet 330 and 350C. Before reading it, read the functional overview of the DesignJet 220 ' HP DesignJet 220 and HP DesignJet 200 Plotters - Service Manual," part number C3187 90000. (Information on the DesignJet 650C ' HP C2858B/C2859B DesignJet 650C Service Manual," part number C2858 90000 Rev B).
Loading Sheet Media
The actions performed by the plotters in loading sheet media are similar to those of the DesignJet 220. (There are some differences due to the different position of the media sensor.) The following diagram shows the sheet media loading sequence. The vertical arrows represent movement of the media. The thick horizontal bars represent movement of the carriage to sense the media edges.
0
1 2 3 4 7 5 15
6 8 9 11 10
12 13 14
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During sheet media loading, the plotter: 0 Detects the front edge of the media. (Media sensor located before pinch arm stops.) 1 Grips and advances the media. 2 Moves the media forwards and backwards to check whether it is still present and correctly gripped. 3 Advances the media and rechecks media presence. (The loading process fails if the media sensor detects no media.) 4 Actuates the bail so that the media can advance under it. 5 Moves the media to a given absolute position. 6 Again moves the media forwards and backwards to check for its presence. (The loading process fails if the media sensor detects no media.) 7 Moves the carriage to sense the right and left edges and to check dimensions. 8 Advances the media six inches. 9 Checks the right edge of the media for skew (misalignment). (The loading process fails if the skew is greater than the allowed limits.)
330 350C
10 If the media is slightly misaligned, the plotter gives you the opportunity to realign it. After realigning, the right edge of the media is checked again for skew (misalignment). (The loading process fails if the skew is greater than the allowed limits or if the aligned media is too far away from the load line.) 11 Advances the media until the media sensor detects the end of the media. 12 Checks the position of the right edge of the media. 13 Extrapolates the skew to the upper and lower edges of the media. 14 Calculates the media dimensions: print margin, length and width. 15 Moves the sheet to the printing position and resets the media axis servo position.
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330 350C
Loading Roll Media on the DesignJet 330 and 350C
The following diagram shows the Roll media loading sequence. The vertical arrows represent movement of the media. The thick horizontal bars represent movement of the carriage to sense the media edges.
1 2 3 4 9 5 6 7 8 11 12 10 13
During roll media loading, the plotter: 1 Grips and advances the media. 2 Moves the media forwards and backwards to check whether it is still present and correctly gripped. 3 Advances the media and rechecks media presence. (The loading process fails if the media sensor detects no media.) 4 Actuates the bail so that the media can advance under it. 5 Again moves the media forwards and backwards to check for its presence. (The loading process fails if the media sensor detects no media.) 6 Advances the media several inches and rechecks media presence. (The loading process fails if the media sensor detects no media.) 7 The plotter stops and allows you to realign the media. 8 Again moves the media forwards and backwards to check for its presence. (The loading process fails if the media sensor detects no media.) 9 Moves the media backwards several inches. 10 Moves the carriage to sense the right and left edges and to check dimensions. 11 Advances the media several inches.
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12 Checks the right edge of the media for skew (misalignment). (The loading process fails if the skew is greater than the allowed limits.) 13 Moves the sheet to the printing position and resets the media axis servo position.
330 350C
Roll Media
When a roll feed assembly is installed on the DesignJet 330 and 350C roll media can be used. The roll feed assembly consists of: D D D D A roll feed frame A spindle Two media stops A built in cutter
The roll feed assembly is installed below the sheet media entry path, to allow the ease of loading for sheet media. When roll media is loaded into the plotter, it is passed around a diverter roll, which optimizes the infeed path to the plotter. Once a plot is completed, the built in cutter is manually slid across the paper to cut the plot from the roll. For further information ' User's Guide, chapter 2.
Removing Static Charge from the Media
An anti static brush located under the entry platen prevents static charge from building up on the media. A charge can cause the media to stick to itself and jam the plotter.
Gripping the Media
When you load the media, it is gripped by the pinch arms. There is no pinch arm sensor on the DesignJet 230 and 250C but there is one on the DesignJet 330 and 350C.
330 350C
Pinch Arm Sensor
The pinch arm sensor is a switch sensor that is attached to the spittoon. It detects the position of the pinch arm lever. Linkage, attaching the lever to a cam, causes the cam to release the switch as the pinch arms are raised. The pinch arm sensor is electrically connected to the main PCA.
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Providing a Force on Top of the Media
Bail
The bail provides a normal force on top of the media. Unlike on the DesignJet 220, there is no bail sensor on the DesignJet 230 and 250C and DesignJet 330 and 350C.
Bail Lift Mechanism
The bail features an automatic lift mechanism driven by the media motor using a series of gears and actuated by the cartridge carriage. The mechanism is different from that used in the DesignJet 220. The new cable based design eliminates the torque on the axle of the bail lift cam and thus improves reliability. The new mechanism is also more accessible. (Removal ' page 6 29.)
Moving the Carriage
Carriage Drive Mechanics
Motor, Belt and Pulley D The carriage (Y axis) drive consists of a DC motor directly driving a single belt and the carriage. This replaces the dual belt system of the DesignJet 220. D The motor assembly itself provides the tension needed on the belt, eliminating the need for a separate pulley tensioner. D The belt clamps itself to the carriage; there are no separate belt clamps. D The interface between the motor shaft and belt is friction based. D You can remove the belt without having to remove the pulley on the left end of the belt. Carriage Guidance The carriage moves along on just one stainless steel slider rod. It is guided by two integrated bronze bushings, which are self lubricating, and a back wheel. Positional Feedback An encoder strip, similar to that on the DesignJet 650C, provides feedback on the position of the carriage. The strip does not require adjustment.
Take care not to cut yourself on the encoder strip inside the plotter.
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Detecting the Lines and Media Edges
Line Sensor
The line sensor on the cartridge carriage is used to: D D D D Detect the left and right media edges. Detect and measure lines drawn on media when performing accuracy calibration. Scan the setup and alignment sheets. Find the platen roller reference mark.
330 350C
Providing Ink
Print Cartridges
The DesignJet 250C uses the same four print cartridges as does the DesignJet 650C. The DesignJet 350C uses the same three color print cartridges as does the DesignJet 750C and 755CM plotters and the same black cartridge as the DesignJet 650C. The DesignJet 230 and 330 plotters use only the black cartridge which is used in the DesignJet 650C. Distance between Carriage and Media The distance between the carriage and the writing surface can determine image sharpness. As the distance increases, the drop shape and directionality degrade and are more difficult to predict. You can change the distance using the adjusting screw on the carriage. (Details ' chapter 7.)
Carriage (Side View)
Adjusting Screw Back Slider
Beam Crosssection
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ÎÎ
Bail-Lift Engaging Tab Integrated Line Sensor
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Producing an Image
Print Mode Characteristics
Note that the firmware can recognize from the plot data whether a plot is color or monochrome. You do not set this parameter on the front panel.
230 250C
Monochrome Plots on Paper (or vellum or translucent) Fast Resolution (dpi) Passes per Swath (#) Carriage Speed (ips) Carriage Axis Depletion Media Axis Depletion Pass Advance (swaths) Bidirectional Minimum Pass Time (sec) 300x300 1 26.67 No No 1 Yes 0.5 Normal 600x600 addressable 2 26.67 Yes Yes 0.5 Yes 0.75 Best 600x600 addressable 2 26.67 Yes Yes 0.5 No 0.75
230 250C
Monochrome Plots on Film The characteristics for monochrome plots on film are the same as for monochrome plots on paper, except for the minimum pass time: Minimum Pass Time (sec) 7.6 3.8 3.8
230 250C
Monochrome Plots on Special Paper Fast Resolution (dpi) Passes per Swath (#) Carriage Speed (ips) Carriage Axis Depletion Media Axis Depletion Pass Advance (swaths) Bidirectional Minimum Pass Time (sec) 300x300 1 26.67 No No 1 Yes 0 Normal 600x600 addressable 2 26.67 Yes Yes 0.5 Yes 0 Best 600x600 addressable 2 26.67 Yes Yes 0.5 No 0
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230 250C
Color Plots on Special Paper Fast Resolution (dpi) Passes per Swath (#) Carriage Speed (ips) Carriage Axis Depletion Media Axis Depletion Pass Advance (swaths) Bidirectional Minimum Pass Time (sec) 300x300 1 16.67 No No 1 Yes 0 Normal 300x300 1 16.67 No No 1 No 0 Best 300x300 2 16.67 No No 0.5 No 0
330 350C
Monochrome Plots on Paper and Film Media Fast Resolution (dpi) Passes per Swath (#) Carriage Speed (ips) Carriage Axis Depletion Media Axis Depletion Pass Advance (swaths) Bidirectional Minimum Pass Time (sec): Paper Film 300x300 1 26.67 No No 1 Yes Normal 600x600
addressable
Normal 300x300
addressable
Best 600x600
addressable
Best 300x300
addressable
2 26.67 Yes Yes 0.5 Yes
2 26.67 Yes Yes 0.5 Yes
2 26.67 Yes Yes 0.5 No
1 26.67 Yes Yes 0.5 No
0.5 7.6
.75 3.8
.75 3.8
.75 3.8
.75 3.8
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330 350C
Monochrome Plots on Coated Media Fast Resolution (dpi) Passes per Swath (#) Carriage Speed (ips) Carriage Axis Depletion Media Axis Depletion Pass Advance (swaths) Bidirectional Minimum Pass Time (sec) 300x300 1 26.67 No No 1 Yes 0 Normal 600x600
addressable
Normal 300x300
addressable
Best 600x600
addressable
Best 300x300
addressable
2 26.67 Yes Yes 0.5 Yes 0
1 26.67 No No 1 No 0
2 26.67 Yes Yes 0.5 No 0
1 26.67 No No 1 No 0
330 350C
Color Plots on Paper and Coated Media Fast Resolution (dpi) Passes per Swath (#) Carriage Speed (ips) Carriage Axis Depletion Media Axis Depletion Pass Advance (swaths) Bidirectional Minimum Pass Time (sec) 300x300 1 16.67 No No 1 Yes 0 Normal 300x300 1 16.67 No No 1 No 0 Best 300x300 2 16.67 No No 0.5 No 0
330 350C
Color Plots on Film The characteristics for color plots on film are the same as for color plots on paper, except for the passes per swath (#) and pass advance (swaths): Passes per Swath (#) Pass Advance (swaths) 1 1 2 0.5 4 0.25
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330 350C
Color Plots on Glossy Paper The characteristics for color plots on glossy media are the same as for color plots on paper, except for the passes per swath (#), pass advance (swaths) and bidirectional abilities: Fast Passes per Swath (#) Pass Advance (swaths) Bidirectional 4 0.25 No Normal 4 0.25 No Best 6 0.167 No
Servicing the Cartridges
Service Station
The service station is based on that of the DesignJet 650C, with some differences. D The service station is easier to access and remove, and is replaceable as one unit. D The absence of a drop detector implies a different cartridge maintenance algorithm to guarantee correct nozzle conditions. The plotter warms the nozzles and spits ink: - Before each plot. - After each cartridge change. - While printing, depending on: cartridge, humidity, temperature, and plot ink density. D The ventilation holes, which were located on the service station sled on the DesignJet 650C, are now located on the ink separator to prevent them from becoming clogged.
Spittoon
A single, redesigned spittoon is located on the right side of the plotter.
Primer
The plotters feature a manual primer, based on that of the DeskJet 1200, instead of the automatic one of the DesignJet 650C. (See ' User's Guide, w Cleaning the cartridge nozzles.) D A bellows assembly provides a vacuum to suck ink from the nozzles. The suction tubes have a wider diameter than those of the DesignJet 650C, to help prevent clogging. D An ink separator isolates the bellows from the cartridges, preventing ink contamination of the bellows. Although the primers for the DesignJet 230/250C and DesignJet 330/350C look identical, their characteristics are different. Installing the incorrect primer can damage the cartridges or reduce the servicing of the cartridges. For the correct part numbers for the primers ' chapter 10.
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Plotter Architecture
The plotters have a multiprocessor architecture similar to that of the DesignJet 650C. The following diagram gives an overview of the architecture:
Main Processor (80960CA)
Internal Memory (ROM/RAM)
Expansion Memory (SIMM DRAM)
Upgrade Memory (SIMM ROM)
80960 BUS
Swath RAM (1 Mbyte)
Support & Shuffler ASIC
Encoders & Motor Drivers
IEEE 1284 ASIC Bitronics
Host
RS232C
EEPROM (512 Byte)
Servo Processor (8052)
Nozzle Timing ASIC
Cartridge Drivers
Carriage's Line Detector
Sensors & Front Panel
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Electronics Module
The electronics module includes the main PCA, power supply and fan. It is one exchangeable part; you do not need to open it. If you replace the electronics module, remember to swop any SIMMs from the old module to the new one.
Main PCA Connections
Front Panel 330 350C
J1
Pinch-arm Sensor Cover Sensor Media Sensor Carriage
J13 J2 J3 J5 J6
Media Encoder Media Motor
Electronics Module
J8 J7 J11 Parallel J12 Serial
U19 Firmware SIMM U20 RAM SIMM
Carriage Motor
Sensors
There is no bail sensor for the DesignJet 230 and 250C and DesignJet 330 and 350C. There is no pinch arm sensor on the DesignJet 230 and 250C but there is one on the DesignJet 330 and 350C. The following sensors connect to the main PCA: D The cover sensor is a mechanical switch that detects if the plotter cover has been raised. If you open the cover while the plotter is plotting, the plot is cancelled! D The media sensor detects the presence of media. It is also used to determine media size.
330 350C
D The pinch arm sensor detects whether the pinch arms have been raised. The servo processor uses the sensor to determine the pinch arm position during the initialization sequence.
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ROM
The plotter firmware code is contained on either an in built masked ROM (soldered to the main PCA) or a flash ROM SIMM (installed in the inner most socket at the back of the plotter). If both are present, the plotter recognizes the code on the ROM SIMM instead of that on the in built ROM. The power on LED sequence tells you whether the plotter is using code from in built ROM or from a ROM SIMM. (Details ' page 8 3.) To find out the firmware code revision level that the plotter is using, print a user setup sheet or a service configuration plot.
RAM
The plotters have a standard four megabytes of on board RAM. They also have one RAM expansion socket, which can hold an optional 4 , 8 , 16 or 32 megabyte DRAM SIMM. The socket is the outer most one at the back of the plotter.
EEROM
EEROM is used as nonvolatile storage for calibration and configuration data. Useful information from the EEROM is printed on the service configuration plot ' page 8 49 (DesignJet 230/250C) or page 8 50 (DesignJet 330/350C). The EEROM is soldered to the Main PCA in both new and rebuilt electronic modules. If you clear the EEROM or replace the electronics module, perform all calibrations. Also note that the factory spittoon value on the cleared or new EEROM is 0%. Keep in mind that the value printed on the service configuration plot may greatly underestimate the amount of ink in the spittoon. Future PC based plotter diagnostics will enable you to download information from the old EEROM and upload it to the new EEROM. (Clearing the EEROM ' page 8 54/8 55.)
Input/Output Interfaces
Like the DesignJet 220, the plotters have both a parallel (Bi Tronics) and a serial (RS 232 C) interface. Unlike the DesignJet 650C, they have no modular input/output (MIO). You can connect the plotters to a network by means of an HP JetDirect EX or HP JetDirect EX Plus3 external print server. (See also ' chapter 1, w Network Connections, and chapter 10, w Accessories.) Bi Tronics In addition to the operating modes of the DesignJet 220, the Bi Tronics interfaces of the DesignJet 230 and 250C and DesignJet 330 and 350C feature the extended capability port (ECP) forward and reverse operating modes, providing for faster communication. RS 232 C The supported baudrates are 1200, 2400, 4800, 9600, 19200 and 38400, with eight bits and no parity, or seven bits with either odd or even parity. Mark parity is not supported. Both XON/XOFF and DTR handshaking are supported. ENQ/ACK handshake is not supported.
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Power Supply
An auto ranging power supply is located in the electronics module. (Specifications ' chapter 1, Power Requirements.")
WARNING
The primary side of the power supply contains rectified line voltage that can be lethal when touched even if the ON/OFF switch is OFF. In any case, you should not need to open the electronics module. It is one exchangeable part.
Water Condensation
In humid environments, water may condense on the side plates. A wick attached to the underside of the right side plate routes water drops away from the main PCA electronics.
Memory Usage
It is difficult to calculate the amount of plotter memory needed to plot a drawing of any given file size. Memory is used, not just to hold the input data, but also for system overhead, processing work space, and storage of the internal representation of the plot. Some types of graphics require relatively large amounts of memory. Examples are wide lines, raster fill patterns, polygons, and user defined lines.
Plot Orientation
The output orientation of the drawing also has an impact on memory usage. Compare a plot of horizontal lines with one of vertical lines. Lines plotted parallel to the carriage axis take up considerably less memory than those plotted perpendicular to it. The plotter builds graphic display objects on a swath by swath basis. A horizontal line can be contained in one swath. A vertical line spans many swaths and therefore requires more entries in the plotter's internal display list.
Raster Image Processor
The raster transfer language (RTL) provides a solution to insufficient memory on the plotter. When all the data is sent to the plotter in the order left to right and top to bottom, the plotter is able to plot the data as it receives it. For this to happen, software (a raster image processor) in the computer must first rasterize all the data. The software issues a command (referred to in RTL as no negative motion) telling the plotter that it will not receive data for any media location on which it has already plotted. The use of no negative motion is called flow mode. Data flows through the plotter without being stored in a display list, so the size of the file that you can send is almost unlimited.
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Carriage PCA
The carriage PCA is based on that of the DesignJet 650C. It connects to the main PCA through a long 60 conductor (2x30) trailing cable. The carriage PCA contains: D D D D Optical line sensor Thermistor circuit Linear encoder Cartridge nozzle firing circuit
Some electronic components on the DesignJet 250C and 350C carriage PCA are not present on the DesignJet 230 and 330 carriage PCA. At power on the plotter firmware identifies whether the carriage is for a color or a monochrome model, and behaves accordingly.
Front Panel PCA
The plotters use the same front panel PCA as the DeskJet 550 and DesignJet 220.
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