ROLLER FREE, MINIATURE, PERISTALTIC PUMP WITH RECIPROCATING ACTUATOR
#1

ROLLER FREE, MINIATURE, PERISTALTIC PUMP WITH RECIPROCATING ACTUATOR
Seminar Report
By
MANU.V.S
S7 MECHANICAL ENGINEERING
(PTDC)
DEPARTMENT OF MECHANICAL ENGINEERING
COLLEGE OF ENGINEERING
THIRUVANANTHAPURAM
2010
[attachment=7955]

ABSTRACT
The conventional modes of pumping are centrifugal, reciprocating, gear pump, lobe pump, vane pump etc. But these types of pumping cannot be used in delicate areas such as medical field, labs, pumping different types of fluids etc. Because the fluid comes into contact with the machine parts and thus it gets contaminated. This cannot be tolerated by the human body. The solution for this problem is Peristaltic pump. Cleanup requires only a change of tubing.
Peristaltic pumps operate on a simple principle. The alternating pattern of squeezing and releasing the tubing moves the fluid through the pump. As a roller passes over the tubing, it is first squeezed then released. The progression of this squeezed area forces fluid to move in front of the roller. The tubing behind the rollers recovers its shape, creates a vacuum, and drawing fluid in behind it. As the roller moves faster, vacuum pockets are created more quickly and the fluid moving through the system picks up speed. The rollers act as check valves to prevent siphoning or loss of prime. The distance between the rollers creates a "pillow" of fluid. This volume is specific to the ID of the tubing and the geometry of the rotor.
Rotary peristaltic pumps face the problem of repeatedly compressed and squeezed simultaneously. In order to solve this problem a novel reciprocating type peristaltic pum is introduced in this section. In this type the tube is only squeeze repeatedly and not stretched. This is done by a cam actuated, motor driven actuator. The tube is continuously squeezed and released. This creates a vacuum inside the tube and this vacuum helps suck the liquid inside the tube. In the next stroke the sucked liquid is pumped out through the delivery valve.
This seminar is intended to present an overall view of peristaltic pumps and to introduce the novel type of reciprocating type peristaltic pump. A study of testing the reciprocating peristaltic pump is also introduced in this section.


1. INTRODUCTION
Peristaltic pumps move fluid by exerting forces on the outside of a pumping chamber which often consists of a flexible tube containing the fluid. Many peristaltic pumps have the advantage that the pump actuator components do not touch the fluid and that the pumping chamber can be made disposable to ensure sterility and prevent cross-contamination. Miniature peristaltic pumps have been micro fabricated using polydimethylsiloxane (PDMS) , PDMS bonded to glass , or glass bonded to silicon . Inmost of these, a series of two or more actuators compress regions of a channel (the pumping chamber) to produce a peristaltic wave. In other miniature peristaltic designs, the pump chamber is created from a section of flexible tubing and the pumping action is created by motor-driven rollers, magnetic balls, or drops of magnetic liquid which compress the tube. Here a novel miniature peristaltic pump which uses a single reciprocating actuator motion to produce pumping is described. This pump uses off-the-shelf tubing and can be manufactured using conventional materials and methods including injection molding, stereo lithography, or CNC machining. A version of the pump where the required linear actuation motion is achieved using a small commercial gear motor and a cam is presented here. The motor actuated pump achieves high flow rates (0.8 ml/min) and can operate under relatively high back pressures of up to 48 kPa. The latter values are on par with or higher than many miniature pump devices. The pump is self-priming, tolerant of bubbles and particles, and can pump liquids, gases, foams, and gels. The pump consumes 90mWof electrical power at 3V, and allows control of flow rate by controlling voltage. Although here we present only one size of the pump, we have created smaller and larger versions which achieve 0.1x to 5x the nominal flow rate and/or higher back pressures (up to 69 kPa).


1
1.1 WHAT IS PERISTALSIS?
Peristalsis is the rhythmic contraction of smooth muscles to propel food through the digestive tract. It helps food and water to reach the stomach easily. It acts as a wave through the alimentary canal.

2. ROTARY PERISTALTIC PUMPS

Fig-1
Peristaltic pumps operate on a simple principle. The alternating pattern of squeezing and releasing the tubing moves the fluid through the pump. As a roller passes over the tubing, it is first squeezed then released. The progression of this squeezed area forces fluid to move in front of the roller. The tubing behind the rollers recovers its shape, creates a vacuum, and drawing fluid in behind it. As the roller moves faster, vacuum pockets are created more quickly and the fluid moving through the system picks up speed. The rollers act as check valves to prevent siphoning or loss of prime. The distance between the rollers creates a "pillow" of fluid. This volume is specific to the ID of the tubing and the geometry of the rotor. Flow rate is determined by multiplying pump head
2
speed by the size of the pillow by the number of pillows per revolution. This pillow volume stays very constant except with highly viscous fluids. Among pumps with the same diameter of rotor, pumps with large pillows will deliver higher volumes of fluid per revolution. A greater degree of pulsation exists with these higher flow rates, not unlike the pumping profile of a diaphragm pump. Pumps with small pillows deliver small volumes of fluid per revolution. With many of these small pillows developing in rapid succession, the motion of the fluid appears smoother, similar to that seen in gear pumps.
Fig-1 depicts the principle of a peristaltic pump. Fig-2 shows the actual diagram of a roller peristaltic pump and Fig-3 shows a real life rotary peristaltic pump.


Fig-2











3

Fig-3
3. ADVANTAGES OF PERISTALTIC PUMPS
1. Fluid does not contact any part of the pump except the tubing.
2. No Seals to leak
3. No valves to clog or wear
4. Self priming (up to 30 ft. (8.8 m) in some models)
5. Pumps liquids, gases, solids, or mixed phases
6. Can use one continuous piece of tubing from inlet to outlet
7. Some tubing materials can be easily sterilized.
8. Easily cleaned at the end of the day, saves time, no corners or fluid holes to collect material or bacteria
9. Easy and fast product change—simply change tubing—no cross-contamination
10. Operates in any position (orientation insensitive).
11. Wide range of flow rates
12. Many types of tubing are available.
13. Wide selection of drives/motors
14. Easily repaired
15. Fewer parts to inventory
4
4. DISADVANTAGES OF ROTARY PERISTALTIC PUMPS
• Lesser tube life due to continuous application of both stretching and compression.
• Friction between roller and tube is higher.
5. MINIATURE RECIPROCATING PERISTALTIC PUMPS
A version of the pump where the required linear actuation motion is achieved using a small commercial gear motor and a cam is presented here. The motor actuated pump achieves high flow rates (0.8 ml/min) and can operate under relatively high back pressures of up to 48 kPa. The latter values are on par with or higher than many miniature pump devices . The pump is self-priming, tolerant of bubbles and particles, and can pump liquids, gases, foams, and gels. The pump consumes 90mWof electrical power at 3V, and allows control of flow rate by controlling voltage.
5.1 WORKING

Fig-4



5

Fig-5


Fig-6
6
The pump is shown in Fig. 4 and consists of four stand-alone parts: the pump body, flexible tubing, cam, and motor. To describe its operation, we divide these into seven functional components: flexible tubing, plunger arm, plunger, upstream valve, down stream valve, pre-constriction, and an actuator. The actuator presented here is a DC electric gear motor with a cam. The actuator pushes down the plunger arm, forcing it to rotate counter-clockwise about its attachment to the base. This attachment is the thin (tapers down to 0.3mm thickness), curved section of material on the right. This motion causes the plunger to pinch the tube against a protrusion in the pump base, thus forming and closing the upstream valve (Fig. 4). The thin “web” between the plunger arm and plunger (which tapers down to 0.3mm thickness) then forces the plunger arm to rotate clockwise about the protrusion in the base and pushdown on the pump chamber (the section of the tube under the plunger). This raises the pressure in the pump chamber until
the downstream valve (a passive element where the tube is normally pinched closed at a narrow constriction integrated into the pump body as shown) opens, expelling fluid to the outlet (Fig. 5). After the fluid is expelled and pressure in the pump chamber has decreased, the downstream valve closes. Further rotation of the cam removes the actuator force. The plunger then lifts off the pump chamber and upstream valve. This allows more fluid to enter the pump chamber from the inlet (Fig. 6). A vertical 2.3mm×1.5mm thru-slot in the pump body with the long axis arranged perpendicular to the plane in which the tubing is flattened serves as a preconstruction. This partially compresses but does not close the tube and helps the upstream valve section spring open quickly after the pressure from the plunger arm is released. The complete pumping and valving actions are created from the motion of a single linear actuator. This pumping action is therefore very different from traveling-wave-type compression caused by moving rollers in conventional peristaltic pumps. This allows for use of linear actuators with the pump. This design shall yield longer tubing life than typical roller designs as it subjects the tube

7
to only one deformation mode compression); while roller-based designs subject the tubing to both compression and longitudinal stretch. This design requires no additional valves or internal seals. Fig-7 shows a real life reciprocating peristaltic pump.

Fig-7

5.2 Materials

Pump Body:

Delrin Acetal Plastic

Tubing:
Polyvinyl chloride (PVC)
Silicone rubber
Fluoropolymer
5.3 Advantages of Reciprocating Peristaltic pump

• Less wear and tear on tube as only one type of loading come into it (Compression)
• Longer tube life

8
6. Testing the pump

Fig-8
Fig. 8 shows the measurement setup. The flow rate is measured using a flow meter connected between two open, identical reservoirs 1 and 2 (each with 15.9mm inner diameter) filled with deionized water and exposed to atmospheric pressure. The pump draws water directly from reservoir 1. A negligible pressure difference is required to cause flow from reservoir 2 to 1 and to maintain approximately equal liquid levels in both reservoirs. The reservoirs have identical geometry and so measured flow rate is one-half of the flow rates flowing through the pump. This measurement setup is used to avoid unsteady pulsations (order 1 s or faster time scales) in the flow meter. The pressure is measured using a pressure transducer. The pump is operated at constant voltage, and measured current with the respective power supply .The pump is operated for 2min per voltage step and show here the middle 30 s of each data series of flow rate and electrical current (to reject transients associated with pumping and filter instrument noise). For the measurements of Fig. 8 & 9, flow rate and pressure were recorded continuously as back pressure increased. The data was then divided into 20 s segments and the time average pressure and flow rate for each segment is plotted.
9
7. RESULTS
Flow rate dependence on driving voltage and back pressure
The flow rate is measured as a function of driving voltage and back pressure. Fig. 9 shows the measured flow rate at driving voltages in range of 1.75–3 V. 3V was the maximum rated voltage of the gear motor, and 1.75Vwas approximately the lowest voltage which would start the motor. Flow rate increased linearly with increasing driving voltage against a constant back pressure.
















Fig-9
Fig. 10 shows measured flow rate as a function of pump back pressure for operation at 3V. Flow rate decreases from 780_l/min with increasing back pressure up to the maximum back pressure of 48 kPa. The decrease in flow rate with increasing back pressure is likely due to a decrease in net stroke volume. It is attributed to increased intermittent backflows through the downstream valve.





10

Fig-10
8. TYPICAL APPLICATIONS OF PERISTALTIC PUMPS
Dialysis machines
Open-heart bypass pump machines
Infusion pump
Auto Analyzer
Sewage sludge
Aquariums, particularly calcium reactors
Analytical chemistry experiments
Agriculture
Food manufacturing
Beverage dispensing
Chemical
Engineering
Pharmaceutical production
11
Print and packaging
Paint and pigments
Pulp and paper
Science and research
Water and Waste
































12


9. CONCLUSION

A miniature peristaltic pump design which can use a single (linear) actuator motion to effect both valving and pumping actions is presented here. The pump is self-priming, tolerant of bubbles and particles, can pump liquids, foams, and gases, and can be manufactured using conventional materials and methods such as injection molding or CNC machining. All designs presented here were fabricated from Delrin acetal plastic and a flexible silicone tube acts as the pump chamber. The motor actuated pump’s flow rate is linearly dependent on driving voltage in the range of 1.75–3V against a constant back pressure, allowing for easy regulation of flow rate. Pump flow rate decreases from 780_l/min with increasing back pressure up to the maximum back pressure of 48 kPa. The pump consumes ~90mW of power, pumping against minimal back pressure at 3V. However it is estimated that only 6% of this power is used to drive the liquid while over
60% of the power is consumed by the motor and gearbox, motivating improvement in the choice of the actuator. This pump system measures 8mm×22mm×35mm and weighs about 3.6g.












13


10. REFERENCES

[1] D.J. Laser, J.G. Santiago, A review of micropumps, J. Micromech. Microeng. 14
(2004) R35–R64.

[2] B.D. Iverson, S.V. Garimella, Recent advances in microscale pumping technologies:
a review and evaluation, Microfluid Nanofluid 5 (2008) 145–174.

[3] N.J. Graf, M.T. Bowser, A soft-polymer piezoelectric bimorph cantileveractuated
peristaltic micropump, Lab Chip 8 (2008) 1664–1670.

[4] W. Mamanee, A. Tuantranont, N.V. Afzulpurkar, N. Porntheerapat, S. Rahong,
A. Wisitsoraat, PDMS based thermopneumatic peristaltic micropump for
microfluidic systems, J. Phys.: Conf. Ser. 34 (2006) 564–569.

[5] O.C. Jeong, S.W. Park, S.S. Yang, J.J. Pak, Fabrication of a peristalticPDMSmicropump, Sens. Actuators A 123–124 (2005) 453–458.















14
Reply
#2
hi...
thanks for uploading..
cud u pls mail me more details of this topic...
mail id is
naveen_mahres1989[at]yahoo.co.in
Reply
#3
sorry, we can't send it to your id. it is not allowed.
Reply
#4
ok.. then how can i get more details of the topic.. can u suggest any links or sites..??
Reply
#5
did you read the entire report?
Reply
#6

do you have the powerpoint slides of this topic?
Reply

Important Note..!

If you are not satisfied with above reply ,..Please

ASK HERE

So that we will collect data for you and will made reply to the request....OR try below "QUICK REPLY" box to add a reply to this page
Popular Searches: miniature circuit breaker ppt, miniature golf courses for home, free download reciprocating pump, solar reciprocating pump sprayer project, peristaltic self inflation tyre system paper, constuction of single acting reciprocating pump ppt, singal acting reciprocating pump ppt,

[-]
Quick Reply
Message
Type your reply to this message here.

Image Verification
Please enter the text contained within the image into the text box below it. This process is used to prevent automated spam bots.
Image Verification
(case insensitive)

Possibly Related Threads...
Thread Author Replies Views Last Post
  pistonless pump for rocket seminar presentation 8 8,099 07-01-2015, 10:44 PM
Last Post: seminar report asees
  Camless engine with elctromechanical valve actuator computer science crazy 1 3,000 25-01-2013, 11:16 AM
Last Post: seminar details
  ROTARY DISTRIBUTOR DIESEL FUEL INJECTION PUMP project report helper 1 3,282 16-03-2012, 01:04 PM
Last Post: seminar paper
  Pistonless Pump for Rockets full report and ppt project topics 4 6,712 13-02-2012, 12:14 PM
Last Post: seminar paper
  Transit Mixer & Concrete Pump project topics 5 4,760 08-11-2011, 09:49 AM
Last Post: seminar addict
  PERISTALTIC PUMP project report tiger 3 3,851 27-07-2011, 02:10 PM
Last Post: smart paper boy
  Centrifugal and Reciprocating Compressors seminar class 0 1,813 18-02-2011, 09:33 AM
Last Post: seminar class
  Sensors and Actuator System Of Special Hyper Redundant Robot project report helper 0 1,575 02-11-2010, 05:40 PM
Last Post: project report helper
  Piezoelectric actuator seminar surveyer 0 1,454 30-10-2010, 05:24 PM
Last Post: seminar surveyer
  RECIPROCATING PUMPS project report helper 0 2,415 13-10-2010, 04:00 PM
Last Post: project report helper

Forum Jump: