PIEZOELECTRIC DISC PUMP USER MANUAL
The Lee Company
A white piezoelectric disc pump with a small orange wire connector is shown.
Website: www.theleeco.com
1. DISCLAIMER
This resource is provided "as is" and without any warranty of any kind, and its use is at your own risk. The Lee Company does not warrant the performance or results that you may obtain by using this resource. The Lee Company makes no warranties regarding this resource, express or implied, including as to non-infringement, merchantability, or fitness for any particular purpose. To the maximum extent permitted by law The Lee Company disclaims liability for any loss or damage resulting from use of this resource, whether arising under contract, tort (including negligence), strict liability, or otherwise, and whether direct, consequential, indirect, or otherwise, even if The Lee Company has been advised of the possibility of such damages, or for any claim from any third party.
2. SPECIAL NOTICES
Throughout this User Manual, special notices relating to the safe and correct operation of the Piezoelectric Disc Pumps are formatted and highlighted as follows:
- [!] CAUTION: Instructions to ensure correct operation of the equipment and/or for avoiding damage to the equipment.
- [!] WARNING: Instructions relating to the safety of the operator and avoiding injury.
3. INTRODUCTION
3.1. Piezoelectric Disc Pump
The Lee Company's piezoelectric disc pumps are a multi-award winning technology which makes use of advances in the field of non-linear acoustics to offer the following unique features:
- silent operation
- ultra-smooth flow
- millisecond responsiveness
- compact form factor
- high-precision controllability
In contrast to conventional air pumping mechanisms (such as diaphragm and piston pumps), the disc pumps do not rely on the bulk compression of air within a cavity. Instead, the disc pumps generate a high amplitude, high frequency acoustic standing wave within a specially designed acoustic cavity. The operating frequency varies part-to-part and with pump operating conditions (e.g. temperature, pressure, etc). A dedicated drive circuit is therefore required to identify and track this frequency over time.
Figure 1 illustrates a schematic of the disc pump, showing the piezoelectric actuator, cavity, air inlet, and air outlet. It also depicts the resulting pressure wave within the cavity.
4. SAFETY
[!] WARNING: The equipment described in this document is intended for use by skilled and competent personnel only. Further, the equipment is provided in a 'bare' format enabling users to integrate it into test fixtures, prototypes and product assemblies.
The user should satisfy themselves that the equipment is, and remains fit for, the intended use. The user accepts that The Lee Company shall not be held responsible or liable for any injury, damage or loss to property, person or otherwise, resulting from use of the equipment.
In order to aid assessment of the safety of the equipment, the following indicative electrical data are provided:
- For typical disc pump driver circuits:
- A.C. voltage on the PCB: 120 Vpp max. (at 20 – 22 kHz)
- D.C. voltage on the PCB: 60 V max.
All disc pumps emit ultrasound in operation. The following data are provided for operation at maximum power (1.4W) at a distance of 30cm:
- Sound pressure level: 70-80 dB SPL @ 30 cm typ. (at 20-22 kHz)1
1 Equivalent to <10 phon per ISO 226:2003 and related studies, 30 cm equivalent measurement distance
[!] WARNING: Take care during use of disc pump driver circuits not to create short circuits between exposed conductive parts of the PCBs. Short circuits may lead to malfunctioning and heating.
5. PIEZOELECTRIC DISC PUMP OVERVIEW
Figure 2 shows piezoelectric pumps from the BL, XP, LT, HP, and US Series, indicating their A- Electrical, B- Pneumatic, and C- Mechanical interfaces.
The piezoelectric disc pump comes in a range of forms, with different mechanical and pneumatic installation requirements, as described in the following section. The table below provides a summary of the differences between the models.
| Series | Mechanical Mounting | Pneumatic Connections | Electrical Connections |
|---|---|---|---|
| BL/XP/LT | 2 off 2.2 mm diameter eyelets | 4 off ~ 3.1 mm diameter barbs. Appropriate links between barbs required, depending on the product | 4.5 mm wide electrical connector to fit 8-way 0.5mm FPC Connector |
| HP | 2 off ~ 3.7 mm diameter barbs. One inlet, one outlet | ||
| US | 3 off 2.2 mm diameter eyelets | X1 ~ 4 mm diameter connector intended for O-ring mounting. |
6. INSTALLATION
6.1. Mechanical - Pump Mounting
All pump series can be mounted via the 2.2 mm diameter eyelets provided. The pump should be mounted using a pair of O-rings (one above and one below, as shown below) and a nylon bolt to isolate the high frequency vibration of the pump and avoid audible noise.
Figure 3 provides an example of mechanical pump mounting using two O-rings and a nylon bolt to prevent audible noise.
Figure 4 shows images illustrating the O-ring appearance as the nylon bolt is tightened. O-rings should be well compressed as shown in (b). Under tightening (a) or over tightening (c) may lead to audible noise.
Figure 5 shows the BL/XP/LT Series Mounting Geometry with dimensions in mm [inches].
Figure 6 shows the HP Series Mounting Geometry with dimensions in mm [inches].
Figure 7 shows the US Mounting Geometry with dimensions in mm [inches].
6.2. Pneumatic - Pump Manifolding
6.2.1. Inlet filtration requirements
[!] TAKE NOTE: All disc pumps should be operated with an inlet filter to prevent ingestion of debris that might otherwise shorten the operational life of the pump. The Lee Company recommends that a non-shedding filter with a pore size less than 3 microns is used.
6.2.2. BL/XP/LT Series pumps
For the BL, XP and LT pumps, which all have 4 pneumatic ports, it is important to connect the ports correctly depending on the pump configuration (series or parallel) to avoid poor performance and damage to the pump.
The configuration can be determined from the description of the product purchased or from the pump label, as shown below:
Figure 8 illustrates how to identify the pump configuration by the label, showing "xxSnn" for series configuration and "xxPnn" for parallel configuration.
BL/XP/LT Series pumps - series configuration pumps
For series configuration pumps:
- Ports 2 and 4 must be linked (see the pump Accessories for suggested coupler)
- Port 3 is inlet
- Port 1 is discharge
Figure 9 shows BL/XP/LT Series, series configuration pumps with port numbering, indicating DISCHARGE (PORT 1), PORT 2, PORT 3 (INLET), PORT 4, and LINK PORTS 2 & 4.
BL/XP/LT Series pumps – parallel configuration pumps
For parallel configuration pumps:
- Ports 2 and 4 are the common inlet and should be linked*
- Ports 1 and 3 are the common discharge and should be linked *
* (see the pump Accessories for suggested coupler)
Figure 10 shows BL/XP/LT Series, parallel configuration pumps with port numbering, indicating COMMON DISCHARGE (PORTS 1 & 3), PORT 2, PORT 4 (COMMON INLET).
6.2.3. HP Series pumps
For HP Series pumps:
- Ports 2 is the inlet
- Ports 1 is the discharge
Figure 11 shows HP Series pumps with port numbering, indicating DISCHARGE (PORT 1) and INLET (PORT 2).
6.2.4. US Series pumps
For US Series pumps:
- Port 1 is the outlet
- The inlet is filtered and not connectable
Figure 12 shows US Series pumps with port numbering, indicating FILTERED INLET and PORT 1 (OUTLET).
6.3. Electrical - Pump "Flexi Tail" Connector
The disc pump uses an FFC (flat flex connector) compatible with most 8-way 0.5mm pitch FFC connectors. The General Purpose Disc Pump Drive PCB has such a connector, and it is important that the disc pump.
- Ensure the connector is fully open, by sliding the brown clasp of the connector horizontally out from the driver.
- Slide the Disc Pump "Flexi Tail" into the connector housing. Initially some friction is felt, continue pushing the connector in until a hard stop is reached.
- Push the connector closed, applying even pressure to each end.
- Visually inspect the connection, ~5mm should be exposed which would verify that the "Flexi Tail" is properly seated into the connector.
Figure 13 illustrates the process of connecting a pump to the Drive PCB.
7. SYSTEM OPERATION
Once the disc pump has been installed correctly, it can be made to provide pneumatic output (pressure and/or flow) by applying a suitable a.c. drive signal to the pump electrical contacts. Details of this drive signal such as the waveform, frequency and voltage, must be continuously optimised to provide high pump efficiency.
Several suitable drive circuits are available from The Lee Company, and technical resources allowing engineers to integrate these circuits into their own products are available on request.
The maximum pneumatic output provided by a pump at a given drive power can be visualised by a load-line, as shown in Figure 14 below. The maximum pressure which can be generated (when there is no 'flow' requirement) is referred to as the Stall Pressure. The maximum flow rate which can be generated (when there is no pressure drop through the system) is referred to as the Free Flow. As the pump can be driven anywhere from 0 – 100% of the specified output, all flow and pressure combinations within the load-line envelope can be achieved.
Figure 14 shows a typical pump load-line, illustrating the relationship between Pressure and Flow, with 'Stall Pressure' and 'Free flow' indicated.
8. ACCESSORIES
8.1. UACX0500500H (prototype C-coupler)
The C-coupler provides a convenient method for linking ports in the series configuration pumps in prototype systems, as described in Section 6.2.
Materials: Accura Extreme Polymer
Notes: Note that these prototype components are fabricated by SLA and are therefore not recommended for use in mass-produced products. The Lee Company make no guarantees concerning the performance of this component with respect but not limited to: Burst pressure, Working pressure, Materials/environmental compatibility, UV exposure.
Figure 15 shows Part UACX0500500H (C-coupler).
8.2. UACX0500550H (prototype Y-coupler)
The Y-coupler provides a convenient method for linking ports in the parallel configuration pumps in prototype systems, as described in Section 6.2.
Figure 16 shows Part UACX0500550H (Y-coupler).
Materials: Accura Extreme Polymer
Notes: Note that these prototype components are fabricated by SLA and are therefore not recommended for use in mass-produced products. The Lee Company makes no guarantees concerning the performance of this component with respect but not limited to: Burst pressure, Working pressure, Materials/environmental compatibility, UV exposure.
8.3. UACX0500750H (Filter)
It is recommended that the pump inlet is connected to a filter with a pore size of <3 µm to prevent ingress of debris which may reduce the performance of the pump.
Figure 17 shows Part UACX0500750H (Filter).
Materials: Polypropylene Housing, Glass Microfibre membrane
Notes: 30 mm HPLC Syringe Filter, Non-sterile, Pore size of 1.2 µm.
9. SUPPORT
The support section of The Lee Company website www.theleeco.com/discpumps provides technical information, FAQs, troubleshooting and documentation for download, including a range of application notes.
For additional technical support, please contact your Lee Sales Engineer.
10. CERTIFICATE OF CONFORMITY
EC and UKCA Declaration of Conformity
Products: Piezoelectric disc pumps and related modules, drive electronics and accessories
Models:
- Piezoelectric disc pumps: UBLB5xxxxxxx (BL Series Disc Pumps), UXPB5xxxxxxx (XP Series Disc Pumps), UHPB5xxxxxxx (HP Series Disc Pumps), UHPB5xxxxxxx (US Series Disc Pumps)
- Piezoelectric disc pump modules: UxxC5xxxxxxx (Smart Pump Modules incorporating any of the XP, BP, LT or HP Pump Series)
- Drive electronics and accessories: UEKA0300000A (General Purpose Disc Pump Driver), UEKA0300050A (Evaluation Kit Motherboard), UACX0500100E (Breakout Board), UACX0500400E (SPM Communication Cable)
Manufacturer: LEE Ventus Ltd, Melbourn Science Park, Royston, Herts, SG8 6EE, UK
EU Authorised Representative: The Lee Company Scandinavia AB, Stormbyvägen 2-4, 163 55 Spånga, Sweden
Declaration: We hereby declare that the products above comply with all relevant provisions of the following directives:
- Restriction of Hazardous Substances Directive 2011/65/EU
- The Restriction of the Use of Certain Hazardous Substances in Electrical and Electronic Equipment Regulations 2012 No. 3032
Standards: The products have been evaluated in accordance with the following harmonised standards:
- EN IEC 63000:2018
A technical file for each product is retained at the manufacturer's address.
Signed by Tom Harrison, Managing Director.
11. REVISION HISTORY
| Revision | Date | Details |
|---|---|---|
| v01 | 07 June 2023 | Branding changes, inclusion of accessories and Certificate of Conformity |
| 220513 | 13 May 2022 | Initial release. |
The Lee Company | Miniature Precision Fluid Control
