Engine Valve Dynamics Volts

Transcription

1 Application Note 4 Dec 2009 Engine Valve Dynamics THE PROBLEM A diesel engine manufacturer had a requirement to measure the stroking motion of a valve with: Max. Displacement = 10 mm Bandwidth = 50 KHz Tests would be performed indoor without engine fi ring. The Solution A Philtec model D125 probe was installed at a angle to the valve stem and positioned on the lower part of the valve fl are can detect valve motion. The sensor was calibrated to the valve fl are with very good results. 10 mm Stroke Model D125 Calibration To Valve Probe at 45 with 4 mm Gap To Valve Shaft Volts Fiber Optic Probe Gap, mm The D125 probe is shown in the picture to the right. A special threaded adapter with compression fi t- ting was supplied. This adaptor was mounted on the engine bulkhead, and it allowed for adjustment and locking of the probe position.

2 8 June 2005 DMS DIGITAL SENSOR UPDATES The easiest way to get a DMS sensor up and running is to use operating software. Two programs are available: A LabVIEW beta project A Visual Basic demonstration project. This free software can be found on our website at /firmware.htm minidms APPLICATION A customer purchased two minidms systems for mounting on a large centrifuge. This required small lightweight sensors and electronics. The sensor tips would be exposed to 100 G s. The sensor models with 30 Ft long fi beroptic cables sheathed with pvc tubing are shown below: mdms-d21-b1c8e and mdms-rc60-b1c8e Firmware is the internal programming code of the sensors. The fi rmware is updated frequently as the product line evolves. Updates might be issued to fi x bugs in the code, to increase speed, to improve a function of the sensor, or to add new functionality. The most current version of the fi rmware (presently 2.546) is always found at the above address. Your customers can update their DMS units by downloading the current fi rmware using their own PC. The process is simple and self-prompting. RS232 A complete RS232 command instruction set is provided on the fi rmware update page. This instruction set has now been updated with specifi c details on how to achieve 5 KHz data transfer rates. Lab FOR PROGRAMMERS VIEW and Visual Basic drivers for operation of DMS units are provided at this link with their source code. Programmers can use the code as a starting point for their own development work.

3 10 June 2005 JET ENGINE TESTS Thrust Reversors Philtec has supplied sensors for aircraft fl ight tests for the measurement of displacement of thrust reversors. The requirements of the application are: ±15 mm displacement -55 C to +150 C 300 Hz Frequency Response The Sale The customer purchased 7 sensors, model D170-C1EPT5, shown in the drawing here. AMPLIFIER Ø8.38 SS INTERLOK Ø 9.52 x 16L COLLAR 30 mm mm 17 Ft 7.9 SQUARE CROSS SECTION Ø 4.76 O. D. Ø 4.32 Fiber Bundle 250 C MAX. TEMP. Engine Tests Philtec has supplied sensors for aircraft engine tests for the measurement of displacement of engine support structures during a catastrophic loss of an engine. The requirements of the application are: 30 mm displacement side-viewing probes with custom mounting standard frequency response The Sale The customer purchased 10 sensors with 40 foot long cables, model D171-BEST7, with custom mounting brackets incorporated into the sensor tip design. D171-BEST7

4 13 June 2005 SMALL SENSORS for STRONG ELECTRO-MAGNETIC FIELDS The Problem To make accurate non-contact displacement measurements of very small components in strong electromagnetic fields. The Sale The customer purchased 2 sensors with 4 spare tips, model D21-BC6ET7 with 20 ft long fiberoptic cables having an in-line connector 3 Ft from the sensor tips. PVC over nylon wrap was used to cover most of the fiberoptics. Two tip designs were required: one right angle and one very short straight tip 0.1 long. The fi beroptics to the short straight tip were covered only with pvc to keep the size as small as possible. The right angle tip was formed using brass tubing (non-magnetic) and the tip collar was made from machinable plastic The electronics were built with a 10 KHz cutoff frequency

5 27 Jun 2005 SENSORS FOR AUTOMOTIVE CRASH TESTS A car door latch linkage was sent to us for an evaluation. The customer needed a sensor to measure the deflection of a part in the linkage during crash testing. They needed to determine if the car door would open during the crash test and if so, at what point during the crash sequence. APPLICATION The Problem The linkage part to be measured is very small The part rotates about a pivot point as it moves The part is dull 4 mm displacement is required The Solution Philtec s model D100 sensor with a spot size of 2.5 mm and range of 10 mm seemed a good fit. We fixtured the test parts and made some successful measurements which are shown in the video clip below. Since this target is not perpendicular to the sensor and it rotates as it translates, the response of the sensor to the motion of this target must be calibrated in-situ by the customer. Door Latch Assembly Model D100 Probe click on image above to view video clip must have Acrobat 5.0 or higher

6 29 Jun 2005 A section SENSOR FOR AUTOMOTIVE CONVERTIBLE TOP TESTS from the support frame of an automotive convertible top was sent to the factory for an evaluation. APPLICATION The Problem The part to be measured is black anodized 3/8 Minimum Gap Needed To Avoid Interference At Least 1/4 Operating Range Required Model RC190 Probe Calibration setup The customer needed a sensor to measure the lateral (horizontal) position of the frame after it opened and returned to the closed position. The requirement was for the frame to return to its rest position within ±1/8. The bottom edge of the frame has a lip that protrudes ¼. Therefore the sensor needs to operate at a standoff distance greater than ¼ to avoid interference with the lifting of the frame. ¼ Measure Here A model RC190-R sensor with ambient light rejection was built and calibrated to the black target. Ambient Light Rejection (Option R) was added because of the low signal strength of light reflected from the black anodized frame. Volts Model RC190-R Calibration To Black Frame Sample SENSITIVITY = 12.4 mv/mil Probe tip 1 The model RC190 sensor meets this requirement. It can be used to make measurements for gaps of 350 to 800 mils Gap, mils Linear Range ± 1% = mils

7 7 July 2005 MULTI-CHANNEL PASSTHRU for HIGH VACUUM (10-7 Torr)* two or more sensors are required to measure in BvFWhen high vacuum our multi-channel vacuum passthru BvF is a great saver of space and money. One BvF assembly can pass up to 8 D model sensors (two legs each) or 5 RC model sensors (three legs each) APPLICATION The Problem Six sensors were required to pass thru an ISO100 vacuum fl ange: DMS-RC units DMS-RC unit DMS-D units All 6 sensors had 14 foot long cables in vacuum and 9 foot long cables outside the vacuum chamber. The RC171 and the D170 sensors have very large fi ber bundles. A problem we faced in producing this order was getting all 6 sensors to fi t into the passthru ports which are distributed over a 25 mm circular area. The photo below shows the problem was solved by making the fi beroptic ends with different leg lengths, thereby avoiding interference with the collar hardware. * Inside the BvF, a Ø 25 mm fused fi beroptic image rod passes the sensor signal channels across the vacuum bulkhead. The glass rod is sealed with a Swagelok TM Ultra-torr compression fi tting which is welded to the I.D. of the BvF. Precision machined end caps contain 16 ports on each end for accurate alignment of the fi beroptic bundles.

8 High Pressure Application 17 July 2006 An OEM customer has an application requiring exceptional stability from sensors under pressure. Application Requirements model DMS-D63 Pressure Range - 0 to 1200 psi Stability Under Pressure % Pressure Stability Test A stability test is required for each of these sensors. To perform this test, we install the probe into a pressure vessel with no target external to the probe tip. We monitor the signal reflected back from the window inside the probe tip. The DMS heaters are turned on and the system allowed to reach thermal stability. The Solution - model DMS-D63-T7W A straight thread o-ring seal compression fi tting is brazed to the probe tip at a prescribed fixed distance from the tip end, and a sapphire window is bonded to a ledge inside the probe tip. The customer encloses the DMS sensors in a constant temperature box to minimize drift. Data recording begins at 0 psi for 1 minute and then continues at 400 psi for at least 10 minutes. The data shown below shows a stability under pressure better than 0.025%. ratio, % DMS-D63-T7W ser 292 Pressure Stability Test At 400 psi time, minutes 97.4 DMS-D63-T7W ser 292 Pressure Stability Test At 400 psi ratio, % time, minutes

9 Special Applications 1 Dec 2006 FLIGHT READY HARDWARE Philtec delivered two model D171 sensors with specifi cations suitable for aircraft fl ight: Amplifi er Oper. Temperature -40 C to +71 C Vibration 5 g rms, 5 Hz to 2000 Hz, in any axis MS style connector for (+28 Volt) input power and output signal HIGH PRESSURE TEST A custom sensor model RC171 was delivered for use in a pressure vessel with: 4000 psi 450 C target surface temperature To penetrate and seal the pressure vessel this special probe tip was fabricated with a 6 length of 1/4 annealed SS tubing upon which a Swagelok compression fi tting was installed. A sapphire window was bonded to the sensor tip to seal the fiberoptics. Axial load PSI GLASS SHAPE MEASUREMENT Philtec has received a purchase order to 100 supply ten 10DMS racks each equipped with 10 model RC171 sensors. The customer has supplied glass samples to be used for calibrations of the sensors. Inside the pressure vessel 4000 PSI Axial sensors DMS UPDATE Radial sensors The current version of the DMS Operating Software posted on the web is 0.999h. This corrects some problems found with version 0.999g. Sample 450 C

10 13 March 2007 SPACE SCIENCE - Measure in vacuum NASA JPL Project Early this month we delivered to Nasa s JPL a complex sensor system for high vacuum measurements. The delivered system comprised the following elements: 11 sensors, model mdms-rc100-bvf-c1e having 50 Foot long fi beroptic cables; 25 Feet in vacuum and 25 Feet in ambient One model 10DMS Rack Two model BvF Multi-Channel Vacuum Passthru Assemblies One model Bv3 Single Channel Vacuum Passthru Flange BvF Bv3 is a world leader providing innovative solutions for non-contact displacement measurements in high vacuum.

11 APPLICATION Three mini-dms sensors were purchased for use in a cryogenic imaging system to measure the small gap between a 4K super-conducting magnetic sensor and the vacuum window to the outside world. The magnetic sensor surface will be coplanar with the FO sensor surfaces. The FO sensors will be looking at mirrored targets on the thin vacuum window to measure the gap. The three readouts will also be used for leveling the magnetic sensor coplanar to the window. Sensor requirements: 3 mm range static speed high magnetic field moderate vacuum cryogenic temperature, 4 K Ø 1.54 mm max. allowable probe size mdms-d47-c1c7efv2t3 Sensors for Extreme Environments SOLUTION 15 Oct 2007 To operate in a high magnetic fi eld at 4 K, probes were supplied using brass tips (T3) and tefl on tubing (C7) to sheath the fi beroptic cable (there is no light in the vacuum chamber). To seal vacuum at the bulkhead, the customer selects the Fv2 vacuum feedthru. To solve the problem of 3 mm range with a 1.54 mm diameter probe, we created the model D47 sensor. This new model has almost the same range as our model D64, but the sensor tip diameter is much smaller, only 1.5 mm. 100 mdms-d47 D FUNCTION Distance To Target, mm

12 MEASUREMENTS OF GLASS SHAPE 40 This month we delivered 40 model mcdms-rc171-c1et1 sensors in 10DMS racks to a manufacturer of auto glass windows. These are used to check the shape of windows in production. This application was fi rst highlighted in our E-Newsletter of August 2005: 27 Feb 2008 AUTOMOTIVE GLASS WINDOW SHAPE CONTROL have delivered a total of 21 racks and 210 sensors for this ap- 210 We plication. LVDT s have been traditionally used to gage window shape. The problem with LVDT s is that they can move the glass window when they make contact, shift the glass position, and thereby create measurement errors. Philtec s non-contact fi beroptic probes have solved the problem, and they have been incorporated into the customer s factory gaging process. Calibrations To Window Glass Every Philtec sensor has to be calibrated to each type glass in production. Glasses used In this project have included clear glass, green tinted glass and laminated glass, ranging from 1.6 mm to 5 mm thick.

13 Flight Test Sensors 13 Feb sensors were delivered to a military customer for in-fl ight testing. These sensors were built to meet the following criteria: Max. Displacement = 5 mm Required Accuracy = 100μm Model RC60 Tip Exposure = 450 C at 6 bars pressure Tip Outer diameter = 2 mm Sensor Cable must have two connections Amplifi er Box As Small As Possible Strong Vibration Environment 1,000 volt isolated output Solutions - The Smallest Box We designed a 123 box and circuit board. The box has dimensions 25 x 50 x 75 mm (1 x 2 x 3 ). It is shown here beside our standard RC box and a minidms box. The 123 box has 4 x Ø4.5 mm thru holes for mounting. It has an alodined conductive coating for grounding purposes and a MIL-DTL Micro-D connector for input and output. Solutions - Fiberoptic Cables We provided a 3-part fi beroptic system: 1. The 123 box with connectorized cable 2. An extension cable 3. The sensor tip with connectorized cable Solutions - Sensor Tip To survive the 450 C pressure and vibration environment we used brazed sapphire windows and compression fi ttings on the sensor tips. PLEASE NOTE Due to their small size, the 123 circuit boards have reduced capability...limited high speed and high gain capability, no options A (heater) and no O, G or V10 outputs. RC mdms 123 The new features shown here, the 123 box, micro-d connectors, fi beroptic extension cables and brazed windows are not presently available on our price list. If you develop customer interest in any of these features, please RFQ the factory for price and availablility.

14 Application Note March 2009 Bending Light THE PROBLEM A customer required a curved fi ber optic probe to measure the motion of a target as shown here. As suggested by the customer, we ground and polished the face of the probe parallel to the face of the target, which meant that the ends of the fi bers were polished to a +30 angle. When we illuminated the fi bers to calibrate the probe it was discovered the light beam was bent 50 from the desired horizontal projection... Light Is Bent Away From Target Target Motion THE SOLUTION A Snell s Law calculation showed that changing the polish angle from +30 to -30 should bend the light beam down to 10 off the horizontal direction. The probe was ground and repolished at -30. The resulting beam of light emitted at the desired horizontal projection Light Beam From Probe Is Centered 50 From Horizontal 30 Axis of Fibers Calculated Center of Light Beam 10 off Horizontal Grind & Repolish At -30 To Fix Problem -30 OTHER APPLICATIONS This concept of bending light can be applied to other applications that can only permit the use of straight probes. For example, where space restrictions do not allow the installation of a bent or curved probe to achieve perpendicularity to a target, polishing a straight probe tip to the appropriate angle can achieve the desired perpendicularity of the light beam...

15 27 August 2010 D Philtec : Philtec 1. Silicon Wafer Production Philtec mdms-rc100-t7 Chuck 2 Silicon Wafer Production Philtec D63-H1T1/T4 50 KHz 3. Soil Testing torsional shear test machines ±20 Philtec D63-BEPT1 shear strain resolution 4. Gear Testing P recision gear test machines Philtec mdms-d63-t7 Recorded gear signatures...