Note: Descriptions are shown in the official language in which they were submitted.
W~'32/0~ Pcr/u~91/r)7287
TI~LE
ROTATING MACHINERY DIAGNOSTIC SYSTEM
Technical Field
-
The invention relates to a system for maintaining
equipment whlch includes two machines having
interconnected shafts which includes measuring alignment
and bearing temperature and instructing the mechanic to
perform needed maintenance.
Backaround Art
Wherever two rotating shafts are coupled together it is
important that their axis of rotation be the same.
Misalignment of the sha~t causes vibrations which cause
excessive wear and even destruction of couplings,
bearings, seals, gears and other components. Today,
misalignment is the primary cause of more than 50 percent
of all rotating machinery failures in many industries.
Therefore, most owners of rotating machinery rou~inely
inspect their equipment and make appropriate adjustments
to correct misalignment.
There are well known equations which can be used to
determine how to adjust the position of two coupled
machines so that the interconnected shafts between them
are properly aligned. To use the equations one must make
certain measurements, insert those measuremen~s in the
equations and solve them. The solutions will tell the
user how much and in what direction to move the machines
so that their shafts will be properly aligned. Although
W092/0~ CT/U~91/S)7287
2r~7 ~57 - - 2
these equacions are well known they are seldom used.
People in the field are unwilling to take the time to
make the necessary measurements and solve the equations.
Many are also comfortable in using the equations because
they fear they will enter the wrong measurements or make
other mistakes.
The result is that most alignments are now done by trial
and error or visual inspection. The trial and error
method is costly and time consuming. Through experience
many people have developed a "feel" for proper alignment
and rely upon that "feel" to do the job. However,
misalignments of a few thousands of an inch cannot be
seen, yet they can cause serious damage. Usually an
alignment is considered to be proper when it in fact is
not.
United States Patent No. 4,436,438 discloses a calculator
which will tell any mechanic how to align coupled
machinery. Through a unique visual display the
calculator tells the mechanic what measurements to make
and in what order to make them.l The mechanic simply
enters those measurements in the sequence specified by
the calculator and the device will tell him how much to
shim the front and back feet of one of the coupled
machines so that the coupled shafts will be properly
aligned. Although this calculator represented a
significant advance in the alignment field, it has
several shortcomings. It cannot store information from
several machines nor transmit information. All data must
be manually entered. Users of the calculators of the
prior art could only compensate for temperature changes
and sag in measuring equipment by following detailed
written instructions or using estimated conversion
,.
W092/~1 P~ 91/0728,
- 3 -
factors. There are no safeguards to assure that actual
data was taken or entered. The calculator cannot provide
customized instructions to the mechanic. The calculator
cannot accept other information about the coupled
macnines such as bearing temperature or conditlons, such
as bearing noise, which are observed by the mechanic.
Yet, that information is important to a preventive
maintenance program.
Disclosure of ~nvention
We provide a rotating equipment diagnostic system that
overcomes the shortcomings of the calculator of United
States Patent No. 4,463,438. Our system includes a
keyboard for entry of numerical data and observations
about any rotating system. Like the calculator of the
'438 patent, we provide a visual display which shows the
technician what measurements to take and an LCD which
display the data as it is entered and the results from
the alignment method selected. Our system, however, is
capable of receiving data electronically from optical
sensors or electronic gauges or from an external computer
or other source which contains information about the
system. Additionally, our system can store information
about any rotating machinery for later use.
We prefer to provide a memory card which enables the user
to install a variety of memory containing customized
programs and one or more databases~ Such programs may
allow the user to receive data from electronic sensors,
~ive the user a route to follow in checking equipment,
compare data taken at other times on the same machine,
contain tolerances for the machines which are routinely
inspected, or provide other data processing. Moreover,
'. ~ ' ..
'
W0~2/0~1 PCr/US~)1/07287
; 4
our calculator allows the user to input custom programs
into the unit.
We also provide a two line, forty character LCD display
~hich displa-y-a prin~e~ me~sages. These messages could be
short commands requiring the user to enter data or
notices that simply advise the mechanic who does the
alignment about conditions of the machines or other
useful information.
We also prefer to provide a bar code reader which permits
users to place bar codes on their equipment and thereby
identify each machine ~eing examined.
The system is compact and easy to transport to and from
the jobsite. It can operate on AC or battery power.
Because it can be made from off the shelf components and
employs printed circuitry it is durable and relatively
inexpensive to produce.
Other details, objects and advantages of the invention
will become apparent as a description of a present
preferred embodiment of the invention proceeds.
BriQf Description of Drawinqs
In the accompanying drawings, we have shown a present
preferred embodiment of the invention in which:
Figure 1 is a perspective view of a present preferred
embodiment of the invention;
Figure 2 is a top plan view of the face plate of the
embodiment cf Pig~re l;
. '
WO92/0~1 PCT/U~1/07287
- 5 ~ ~7
Flgure 3 is a block diagram of a present preferred
embodiment of the invention;
Figures 4 is a detailed circuit diagram of the processing
and memory portion of the circuit of the embodimen~ of
the Figure 3;
Figure S is a detailed circuit diagram of the removable
card having a memory and remote computer data entry
portion of the circuit of the embodiment of Figure 3;
Figure 6 is a detailed circuit diagram of the electronic
indicator data entry portion of the circuit of the
embodiment of Figure 3;
F~gure 7 is a detailed circuit diagram of the keyboard
portion of the circuit of the embodiment of Figure 3;
Fi~ure 8 is a detailed circuit diagram of the bar code
reader interface portion of the circuit of Figure 3; and
Figure 9 is a detailed circuit diagram of the liquid
crystal display portion of the circuit of the embodiment
of Figure 3.
Referring to Figures 1 and 2, the calculator is comprised
of a f ace plate 2 fitted onto a housing 4 in which the
circuitry is cantained. The face of the device con~ains
a data entry keyboard 8, power switch 10, method
selection switches 11 thru 19, special function Iceys 20,
alignment keys 21 and LCD display 22. A plurality of
light emitting diodes are provided for identifying
measurements to be taken which are in squares 24 and f or
identifying gauge readings to be ~aken which are in
W092/0~1 PCT/US91/072~7
2~ 7 - 6
circles 25. Blocks 30 and 31 represent the coupled
machines being examined. Arrows within those blocks
illuminate to indicate a direction that the machine
should be moved to align the coupled shafts. Discs 32
and 33 indica~e coupling ends and llne 34 is the coupling
centerline. The diodes light in sequence to tell the
user what data to enter. Because measurements are often
made in eighths of an inch, I prefer to include keys for
those fractions in the data entry keyboard 8 as shown.
Our keyboard also permits entry of negative numbers by
use of the minus "(-)" key. A question mark key
enables the user to enter an unknown value ~ihich can be
solvPd through equations contained in the memory.
We also prefer to store tolerances for each machine to be
inspected. If the results of the measurements and
calculations show a misalig~ment a diode below the " "
or "x" above keys 21 will illuminate to indicate that the
alignment or offset is within our outside tolerable
values. our system is capable of receiving data
electronically from optical measuring devices or
electronic gauges which are connected to the calculator
at ports 71 and 73. Also, we can use a bar code reader
which plugs into port 41 to identify the equipment being
examined and have data about each unit stored in memory.
We also provide an R5232 port 51 to permit our unit to be
connected to a remote computer to which data may be
transferred for storage or analysis.
Best Mode for Carryina Out the Invention
To operate our calculator the user turns on the power
with switch 10 and selects the method he intends to use
with switches 11 thru i9. If he wisnes to use the
WO92~0fi~l PCJ/~S')1/07287
,~r~ 7
-- 7
indicator reverse method (M1), he pushes key 11. An
adjacent diagram 26 illustrates the gauge configuration
for this method. We prefer to provide a segmented light
board under the face plate to backlight the keys. This
backllghting is activated by key 27. Then the mechanic
enters measurements and readings in the sequence given by
diodes 24 and 25. After all data has been entered the
calculator will make the necessary calculation. Then the
mechanic can read in display 22 the amount to shim or
move the machine in the direction indicated by the arrows
in boxes 30 and 31. The calculator will automatically
store information until a new method key is pressed.
Should the user want to keep the information for other
purposes, he can do so by pushing the "Store" key 29.
To illustrate one operation of the invention ln detail,
suppcse the mechanic has chosen the indicator reverse
method (M3). First he will set his gauges as shown in
diagram adjacent key 13. Then he presses the power
switch 10 and key 13. LED's 24 and 25 will light in
sequence to tell the mechanic to enter the appropriate
distances and readings. To enter the data the mechanic
presses the appropriate numerical keys on the keyboard
and the entry is displayed on display 22. If the display
is correct he presses the "Enter" key which enters the
reading into the calculator's memory, clears the display
and causes another LED to light calling for entry of the
next reading. If the mechanic has typed the wrong
numbers and the display is incorrect, he can clear the
display with the "Clear" key and type in the correct
figures. After all entries have been made, appropriate
arrows in box 31 will light to tell the user the
direction to move the machine to be shimmed (MTBS) to
achieve a proper alignment. The dis~ance to shim both
WO(~2~0~l P~TiU~91/U72~7
~ J~57
the front foot and the back foot will appear
automaticall~ in display 22. To check any of the data
entries one can use the recall (RCL) key which will
recall the data entries in order. As each entry is
recalled the appropriate LED's will light to indicate
which measurement is being displayed.
To determine the required horizontal movement the
mechanic depresses the vertical/horizontal (Vert. Hori.)
key which sets the display at zero and causes LED 25 to
light. Both planes are calculated simultaneously but
displayed separately by pressing the vertical/horizontal
key. In using this procedure the user normally will have
to adjust his gauges to compensate for indicator sag
caused by the bending of the mounting hardwar~. In our
unit one can preprogram a notice which tells the mechanic
what compensatory steps should be taken for a particular
machine. The two indicator method works the same way as
the indicator reverse method.
Should the machine to be shimmed have more than two
support points the Intermediate Feet (Intm Feet) key
enables one to determine how much to shim the
intermediate feet. After answers have been obtained for
the front and back feet the operator presses the
intermediate feet key. Then LED 25 will light to signal
that the distance from the front foot to the intermediate
foot should be entered. After the operator enters that
value arrows in box 30 or 31 will light and the amount by
which the intermediate foot must be shimmed will appear
in display 22.
W0~2/0~1 PCT/U591/07287
Z~7~4~3~7
. g
~f one discovers that the machine to be shimmed was
resting on three rather than four feet the gauge readings
will be inaccurate. The clear indicator (Clear Ind) key
will ciear the data which was entered for both gauge
readings. Then the user can correct the "soft foot"
condition, take new gauge readings and enter the new
readings. The distance measurement~ will be retained by
the calculator and need not be entered again.
Those skilled in the art will recognize that the
procedures just described are substantially the same as
the procedure used to operate the calculator of United
States Patent No. 4,463,438. The accuracy of the method
of the '438 patent, however, is dependent upon the
correctness of the data measured, read and entered by the
mechanic. Such human error can be eliminated with the
present calculator. That calculator cannot also retain or
analyze data apart from solving the alignment equations.
We prefer to provide keys which allow the user to retain
and monitor movements and soft foot conditions which
occur over time. By pressing the "Monitor Moves" key the
user will cause the calculator to retain the data
determined for movement of the machine to be shimmed
based upon the data then entered. This data can be
transmitted to an external computer for analysis or
compared to other data according to a program provided.
If a pattern of movement appears this may indicate to the
mechanic that a bearing problem is developing or another
problem is occurring with the machin Therefore, he
will be able to take corrective measures before the
machine fails. Those measures could be taken during the
scheduled shut down of the machinery. Similarly, by
pressing the "Monitor Soft Ft" key the user can tell the
~092/0~l PCTiU~91/07287
- 10 -
calculator that a softfoot condition exists and enter
qauge readings before and after foot adjustments are
made. From this data the calcuiator will tell the user
how to shim the machine to correct the softfoot
con~ition.
There are peculiar equipment configurations which may
requlre special procedures to make an alignment. For
example, it may not be possible because of equipment
configuration to place indicator gauges or take
measurements which are required for the alignment
equations of methods 1, 2 and 3 indicated by keys 11 thru
13. In such circumstances, special technical
applications can be programmed into the calculator to
accommodate these particular circumstances. These
technical applications can be called up by pressing the
"Tech. Appl." key 17. Pressing that key activates a
particular technical application program. That
application may involve taking additional measurements.
It may also involve specific written instructions which
are displayed in liquid crystal display 22.
In many plants certain individuals are assigned to make
regular inspections of plant equipment. These routes
typically include a list of the equipment to be
inspected. Each piece of equipment being identified by a
number or location. With the present calculator, it is
possible to provide a program which describes the route
to be followed by the mechanic. By pushing the "Route"
key the calculator will display in sequence the
identification of the equipment to be inspected. As the
data for each identified piece of equipment is collected
and entered the calculator will record the time of the
ent.y and the correctlve measures indicated. This
W092~0~l PCr/US9l/07287
;7~j57
informa~ion can later be played out from the calculato~
to tell the manager or the maintenance engineer that the
inspec~ions had actually been done and provide the time
of their inspections. ~nowledge of the tlme at whlch
lnspectiorls were made may prove useful in the event o~
equipmen~ failure or in circumstances where current data
appears to be inconsistent with previous data or expected
data. The additional keys "Add Route" and "Skip Route"
allow the user to include additional equipment
identification to the list of routes or to skip a unit in
the listed route.
During the inspection the mechanic may be asked to make
certain observations such as whether an oil leak appears
near the equipment or whether vibration is seen or heard.
The "Enter Notes" key allows the user to inform his
supervisor about the equipment and insert responses
through the keyboard.
It is well known that temperature affects alignment.
Therefore, misalignment indicated during a cold reading
may not necessarily correspond to a misalignment when the
equipment has been operating. Accordingly, we provide
keys 14 and 15 to enable the user to record whether the
equipment is hot or cold. If, for any particular
equipment, alignment differences between cold conditions
and hot conditions are significant, a program can be
provided to accommodate those differences and enable an
alignment to be made whether the system is hot or cold.
"
There are conditions when the normal aliynment
corrections cannot be followed. We provide keys 18 and
19 to allow the user to select an alternative method such
as the compound move, key 19, which recalculates verticai
W0~2/0~l PCr/US91/n72~7
?3 ~i 5 7 -- 12
adjustments in such a manner that both the machine to be
shimmed (MTBS) and the stationary machine (SM) can be
shimmed up to accomplish the vertical alignment when
original answers indicate that the MTBS had to go down
which movement proves to be diff iCuit .
Key 18 enables us to recalculate necessary movements of
what was originally identified as the stationary machine.
Normally, the machine to be shimmed is considered to be
on the right side. However, with our system the machine
to be shimmed may be on the left.
It is very diff~cult in most situations to create a
perfect alignment of coupled shafts. Nevertheless, a
perfe-t alignment is not always required to produce
acceptable bearing wear and equipment life. Accordingly,
it is possible with our system to record tolerances for
individual equipment. After the identification of the
e~uipment has been entered, and appropriate measurements
have been taken and recorded, our calculator will not
only indicate the distances which the machine to be
shimmed must be moved to place the shafts in alignment,
but will also indisate whether that distance is within
tolerances for the machine. This is done by pressing the
vertical, horizontal alignment key (Vert. Hori.) or the
angularity and offset (Angle Offset) key. Diodes under
either the "check" or "x" next to the angularity and
orfset key will illuminate to indicate whether or not
values calculated are within tolerance. If they are out -
of tolerance, the operator may proceed to realign the
machine. When that is done he can enter the new gauge
readings. Then the calculator will indicate whether the
vertical alig~ment, horizontal alignment, angularity and
offset of the coupled shaFts are within toierances.
W092/0~1 PCr/US~ 7287
- 13 - ~r~
As previously mentioned, the supervisor or plant engineer
may want to have the user receive certain notices about
particular equipment. With our calculator he can do that
by recording the notice in memory. When the user enters
an identification of the equipment and a notice has been
recorded, a diode 23 adjacent the "Notices" key will
illuminate. The user then presses the "Notices" key to
acknowledge that he has read the notice in the liquid
crystal display 22.
We prefer to program the calculator to round off all
answers to the nearest one-tenth (i.e. 0.10 thousandths)
because the thinnest shim stock available is 0~50
thousandths.
We also prefer to provide interlocks to prevent loss of
data and incorrect entries. We further prefer to
electronically bypass the "Clear" key when answers are in
the display. Finally, the "Enter" key will cause data
put in the display to be entered and progression ta the
next data entry to automatically occur. An interlack is
pjrovided so that subsequent depressing of the enter key
will not cause progression or any data entry to occur
unless new data has been put into the display. This
interlock feature helps prevent omission of required
data.
The Preferred Circuitry
Figure 3 is a block diagram of the preferred circuitry of
our invention which illustrates how current flows within
the device. A detailed circuit diagram appears in
Figures 4 thru 9. In this circuit, we prefer to use the
components listed in Table I which also contains the
Wo 9~/~6~1 Pcr/~lsg~/o72s7
~r~ 14 -
reference number given each component in the drawings.
Most components are available from a variety of sources
by giving the listed part number. Therefore, sources are
identified for only those parts which are not available
~rom several manufacturers.
TABLE I
Drawina Ref. Part No. Description
27, 74, 80 65C22 Rockwell versatile
interface adaptor (VIA)
42 HBCR-2000/10 Hewlett-Packert bar code
interface
44 74HC373 Latch
46 6116 Static 2k x 8 RAM
52 MAX232 Maxim driver
54 65C52 Rockwell UART chip
74HC00 Gate
56 DS 1217 series Dallas Semiconductor IC
IC card for removable cards
having a memory
57 74HC4075 Gate
58 74HC237 Decoder
65C102 Rockwell CPU
61 74HC14 Inverter Gate
62 27C256 32 K EPRO~
63 16K ROM
64 51256 32K RAM
66 RCT 12421 Dallas Semiconductor
Clock
67 74HC139 Decoder
68 74HC137 Decoder
: -
: '
W092/0~l PCT/US~1/07287
Z~ 57
1~ --
69 74HC08 AND Gate
72 74KC366 Electronic switch
73 LCT 1092 Maxim A/D converter
Referring to Figures 3 and 7 the keyboard 8 is connectedthrough a versatile interface adaptor (VIA) 80 to central
processing unit 60 shown in Figure 4. A second VIA 27
connects liquid crystal display 22 to the processing unit
60. A 32~ erasable programmable memory 62, two 16K
ROM's 63 and 32K static RAM 64, form the base memory for
the system. We prefer to ~rovide a clock 66 connected to
the CPU and memories. CPU 60 is connected to a power
source through inverter gates 61. Decoders 67 and 68
with gates 69 provide decoding for the CPU and memories.
As shown in Figure 5, we prefer to provide a removable
card 56 having a memory which may contain a program
having instructions applicable to particular rotating
machinery with associated gates 57, inverter gates 61 and
decoder 58. This enables us to provide preselected
programs for each calculator so that our system is I
tailored to particular uses and equipment specified by
the customer. These programs may have anything from
specific technical applications to notes from the
supervisor that appear in display 22. Additionally, we
provide an RS232 port 51 with associated decoder 52, UART
54 and gates 55. This enables the user ~o connect the
unit to a remote computer 50 shown by a chain line block
in Figure-3. Then the user can transmit data for storage
or analysis or receive data such as instructions to the
user.
Referring to Figures 3 and 6, we en ble dat~ to be
entered in our system electronically from dial indicators
.
W092/OhWl PcT/uS9l~o7287
2~ v~ 7
- 16 -
through ports 71 or from a temperature probe 75 or other
analog device through port 73. Data coming in through
port 73 passes through analog di~ital converter 76 to VIA
74 and then on to the CPU and memory for storage or
processing. Presently, there are three types of
electronic dial indicators. To enable our system to be
used for all three types of such indicators, we provide a
switch 72 for each input port. This switch and
associated circui~ between dial indicator port 71 allows
our system to recognize the type of electronic indicator
which has been indicated and then allow data to flow
from that indicator into our system. We may also receive
data from a bar code reader wand 40 indicated by a
chainline box in Figure 3. So that the signal from the
bar code reader is useful to our system we provide the
interface circuitry of Figure 8. That circuit includes a
bar code interface unit 42 with associated latch 44 and
memory 46. This portion of the circuit processes the
information which comes in from the wand 40 and then
transmits the data to the processing unit and memory. We
prefer to also connect to the bar code interface a buzzer
or piezo sounder 43 which tells the user that the system
has received the information from the bar code over which
the wand has been passed.
While we have shown and described a present preferred
embodiment of the invention, it is to be distinctly
understood that the invention is not limited thereto but
may be variously practiced within the scope of the
following claims.
