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Universal Dispensing Pump
Speedex
"SPEEDEX - The universal liquid-dispensing
pump"
This high performance laboratory pump is unique
in its kind,because it can dispense liquids with a resolution of 50 ul with a
range of volumes programmable from 100 ul to 5000 ml. (the range can be extended
to higher volumes).
ADVANTAGES
 | High precision:
the dual reciprocating piston dispensing system allows a resolution of 50 ul
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| Wide flow range:
from 1 ml/min to 1.5 l/min with a single pump model
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| Excellent Riproducibility:
the constant flow is maintained over time, contrary to other dispensing
system such as peristaltic and diaphragm pumps subject to aging and
requiring continuous re-calibrations.
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| Chemically inert:
all parts in contact with the pumped fluid are made from chemically-inert
materials, such as PTFE, glass and PEEK.The instruments is therefore
suitable for critical applications such as those involving: aggressive
liquids, organic solvents, biological solutions, etc.
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| Flexible and versatile:
meets all pumping, dispensing and trasferring needs within an unrivalled
wide range of flowing rates and volume capacity.
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| Progrmmable and multifunctional:
a fully-programmable electronic controller offers a wide choice of operating
modes: continuous pumping or transferring at constant flow rate,
manually-controlled or automatic dispensing of programmed volumes,
multi-step and multi-cycle dispensing with individually programmable flow
rate, delay time and volume for each step.
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| Pulsation-free:
the unique design of the pumping system allows a continuous flow rate free
from pulsation and interruptions. A very high accuracy and reproducibility
can be obtained both in terms of flow rate and delivered volume: excellent
for low-pressure chromatography and flash chromatography.
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| Pedal Control:
A pedal control is available as a useful accessory for applications
requiring hand-free operations or for remote operations such as: dispensing
of hazardous fluids under a fume-hood, or bottling in small volume
productions.
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| Self-priming:
the system is entirely self-priming, thanks to the special piston
construction and the absence of dead volume zones.
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| Maintenance-free
the careful choice of materials and the advanced construction techniques
make this pump a virtually maintenance-free device.The hydraulic circuits
only need to be cleaned every time the fluid type is changed: the continuous
flow function simplifies and speeds up the operation.
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| Easy to use:
requires no special skills and can be used by any operator |
The pumping system
is composed of two calibrated glass syringes, 100cc each, with the pistons
operating in reciprocating mode.
The piston are made of solid, virgin PTFE, the sealing is guaranteed by a
particular system with the O-R seals separated from the solvent by a special ́under-skini
system.
The hoses are in semiflexible PTFE and the couplings are screw-type with
nipples in PEEK.
Two PTFE valves of diaphragm-type provide automatic flow reversal when
the two syringes reach the travel limit.
The piston shafts of the two syringes are guided by two high-precision
linear bearings and are driven in a perfectly complementary manner by a
backlash-free timing belt and pulley system.
The high-torque stepper motor (4Nm) guarantees a resolution of 400 steps
per revolution of the motor shaft.The advancement of the pistons is
approximately 0.05 mm per motor commande pulse.Since the delivery of the
syringes is perfectly linear and corresponds to 100 ml for a piston stroke of
100 mm, a final resolution of 50ul is obtained for each command pulse sent to
the motor.
The system microcontroller supplies the stepper motor with discrete steps
or continuous rate at the required speed as needed by the specific duty. The
particular mechanical system design is such that each movement produces exactly
the delivery of equal amounts of solvent, at a constant flow rate and is
linearly proportional to the movement speed.
The limit switch system automatically reverses the direction of the motor
shaft rotation when the syringe pistons reach the upper or lower travel limit.
This system is completely trasparent to the control system, which continues to
send pulses for the delivery of the liquid. When one syringe is completely
empty, its mate, always moving in the apposite direction, (which always moves in
a direction opposite to that of its mate) will have just been filled up. At this
point the automatic system will reverse the rotation of the motor and change the
combination of the 2 valves status. The next command pulse will make the just
filled syringe begin the delivery cycle, while the empty
syringe will start the aspiration cycle.
The valve system (normally closed in stand-by or when switched-off) and
the perfect syringes sealing, implicitly guarantee the complete absence of
siphoning effects during quiescent periods, prevent the contact of the
stationary solvent with air, pollutants, stop evaporation or, worse,
crystallization in case of saline solutions.
The self-priming system: the particular conical shape of the piston top
and the syringe caps, the use of water-repellant material such as PTFE, and the
absence of dead volumes, bleed every trace of air after just a few starting
cycles carried out by the system. This also occurs, abviously, for the washing
of the pumping components and for the complete emptying of the system during
maintenance or prolonged rest periods. The changing of the solvent and the
subsequent ́rinsingi with the new solvent is also greatly facilitated by this
feature.
The outgoing flow is perfectly constant and virtually free of
interruptions, even when the ́exchangingi of functions between the two syringes
takes place: to maintain the maximum precision regarding the absolute value of
the liquid dispensed, a signal is nonetheless generated corresponding to the
short ́deadi time occuring during the motor direction reversal and the exchange
of the four solenoid valves (time during which the solvent is not delivered).
The microcontroller takes this time into account and consequently adjusts the
real value of the volume delivered both in every instant and overall.
The dual reciprocating pistons design guarantees a solution flow that is
continuous and constant for any quantity: while one syringe is at the injection
stage, the other is being filled, and the functions are interchanged
autotomatically at the end of the stroke without interrupting the filling
operation. The maximum quantity of solution that can be transferred is thus
limited only by capacity of the storage reservoir from which the solvent is
drawn directly.
PUMP TYPE: volumetric,
dual reciprocating piston dispensing
PUMPING UNIT: calibrated glass syringe, capacity 105cc
PISTONE STROKE: 105mm
PISTON MATERIAL: PTFE with O-R gasket mounted with the
"under-skin" technique
SYRINGE PLUG: pressure-type, in PTFE
COUPLINGS: screw-type with conical nipples in PEEK suitable for
semiflexible hoses in PTFE(6 mm)
VALVES:2 diaphragm solenoid valves, normally closed. 24V DC
electromagnets, 100%; valve body:PTFE
PISTON MOVEMENT: linear with precision ball bearing and eye swivel for
compensating asymmetries.
TRASMISSION: trasmission system with steel-reinforced positive drive
timing belt with coupled pulleys for backlash-free operation
DRIVE: stepper motor with 4 Nm torque, step angle 1.8°, operating in
"half step" mode for a total of 400 steps/revolution
RESOLUTION: one step of the motor corresponds to a piston advancement of
approximately 0.05mm, i.e. 50 ul of solution delivered
PISTON MOTION INVERSION: automatic a the end of the piston stroke, with
optical position sensor
AVERAGE DEAD TIME (MOTION REVERSAL AND VALVE COMMUTATION): about 60 msec
DRIVE SPEED: from zero to 30 mm/second(max) corresponding to a flow rate
of approximately 1,5 liters/minute. The theoretic maximum flow is limited in
pratice to 1.5 liters/minute by the section of the hoses and the injector in
order to limit the internal pressure rise
SIZE AND WEIGHT: 180 x 230 mm, height 550 mm. Weight 12 Kg
POWER: 115-230V AC, 50-60Hz single phase, electrical input 65VA
ELECTRONIC
CONTROLLER
For indipendent operation, the instrument has been equipped with an electronic
handheld remote control unit that allows the operator to controll all
operations,choose functions, and change the operating parameters. This accessory
consists of a terminal equipped with a membrane keyboard (21 keys) and a backlit
LCD alphanumeric display with four lines of 16 characters each.
The terminal is connected directly by means of a flexible cable to a connector
on the side panel of the pump. This cable carries the signals for controlling
the pump and also supplies power to the remote control unit.
FUNCTIONS
The functions that the user can set and carry out using the remote control
terminal are the following:
-Manual start/stop of the pump by means of the key or the optional pedal unit
(connected to the pedal input). The type of command given can be: a) momentary,
for as longs as the key (or pedal) is held down, or b) starting with START or
stopping with STOP.
-Dispensing of present aliquots of solvent constant speed
-Dispensing of preset aliquots of solvent in three separate stage (e.g., slow
flow, fast flow, very slow flow or other combinations by choice)
-Dispensing of preset aliquots of solvent at constant speed and repeated for a
preset number of times and with automatic waiting time between one addition and
the next.
-Display of the following parameters: volume delivered, delivery speed, waiting
time between two additions, number of additions.
REMOTE CONTROL TERMINAL
DISPLAY: backlit dot matrix LCD. Alphanumeric characters, 4 lines of 16
characters
KEYBOARD: policarbonate membrane-type, 21 Keys
SOUND SIGNAL: internal buzzer
POWER: supplied directly from the pump circuits through the command cable
CONTROL: internal 8-bit microprocessor with EEPROM memory for permanent
parameters storage
FUNCTIONS:
| manual start/stop of the pump by means of a key or the
optional pedal unit (connected to the pedal input) The type of command given
can be: a) momentary, for as long as the key (or pedal) is held down, or b)
starting with START or stopping with STOP
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| Setting and dispensing of preestablished aliquots of
solvent at constant speed
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| Setting and dispensing of preestablished aliquots of
solvent in three separate stages (e.g. slow flow, fast flow, very slow
flow-or other combinations by choice)
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| Setting and dispensing of preestablished aliquots of
solvent at constant speed and repeated for a preset number of times
MAXIMUM VOLUME SETTING: 6500 ml
MINIMUM VOLUME SETTING: 100ul
RESOLUTION: 50 ul
MAXIMUM DELIVERY SPEED: 1500 ml/minute
MINIMUM DELIVERY SPEED: 1 ml/minute
NUMBER OF REFILLS: manual or preset, from 1 to 99
TIME INTERVAL BETWEEN REFILLS(AUTOMATIC): 1-99 seconds, resolution 1
sec
SIZE AND WEIGHT: 180 x 100 x 40 mm; wheight approx. 200 g |
MAIN APPLICATIONS:
-Universal laboratory dispensing, even for large volumes
-Repetitive multi-dispensing
-Low pressure cromatography
-Decanting of solvents and liquids in general (including aggressive liquids)
-Continuous circulation pump for organic or biological fluids
-Burette for automatic titration
-Continuous flow spectrophotometric analyses
-Biological studies on the perfusion of organs
-On-line process control
-Feeding of reactors for monitoring of pH, conductivity, etc.
-Dispensing under a hood or remote dispensing
-Semi-automatic filling of bottles or phials for small volume productions
(cosmetics, herbal preparation, pharmaceuticals, foods, etc.)
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