Guide to GearSoft
Software Code: 193
INDEX
1 Introduction ... 5
2 Control panel ... 6
3 Entry of initial data – Gear parameters... 8
3.1 Module or Diametral Pitch ... 9
3.2 Correction factor ... 9
3.2.1 Calculating the correction factor through Wildhaber ... 10
3.3 Moment of inertia ... 10
3.4 Profile development ... 10
3.5 Coning angle ... 11
4 Setting the measurement limits ... 12
4.1 "Profile Measurement" Frame... 12
4.1.1 "dfs-de" button ... 13
4.2 "Z Flank Measurement" Frame ... 13
4.3 "Axes" Frame ... 13
4.4 Number of Measurements ... 13
4.5 Buttons and check-boxes ... 14
4.5.1 Resetting procedure... 14
4.5.2 PATH Procedure ... 14
5 Scan positions and additional measurement options ... 16
5.1 Helix-Involute positioning and measurement ... 16
5.1.1 Automatic lead search B ... 17
5.1.2 Measuring the RIGHT flanks only... 17
5.1.3 Involute Measurement through 3-Axes GMM ... 17
5.1.4 Disable Helix measurement – Disable Involute measurement ... 17
5.2 Determining workpiece axis ... 17
5.2.1 Centring on pins ... 18
5.2.2 Alignment on pins ... 18
5.3 Pitch positioning and measurement ... 19
5.3.1 "Division and concentricity" frame ... 19
5.3.2 "Teeth k deviation control" frame ... 19
5.4 Starting the measurement ... 20
6 Measuring a gear ... 21
6.1 Measuring a non-stored gear... 21
6.2 Measuring a stored gear ... 21
7 Measuring sheet parameters ... 22
7.1 "Profile Limits" frame ... 22
7.2 "Z flank limits" frame ... 23
7.3 "Profile classes" frame ... 23
7.4 "Flank classes" frame... 24
7.5 "Division and concentricity" frame ... 24
7.6 "Taperings" frame ... 24
7.7 Distance between pins calculation... 25
7.8 Crowning... 25
7.9 Identification data ... 25
7.10 Machine corrections... 25
8 Parameters that define quality ... 26
8.1 Profile quality parameters ... 26
8.2 Flank quality parameters... 26
8.4 Classes and evaluation standards ... 29
9 Helix and involute measurement sheet... 31
9.1 Profile graph ... 32
9.2 Helix graph ... 32
10 Division and concentricity measurement sheet ... 34
11 Tolerance areas (K Area) editor and Taperings ... 36
11.1 Inserting the nodes... 37
11.2 Joining nodes to lines or circle arcs ... 38
11.3 Specular tolerance area ... 39
11.4 Reference node inside the tolerance area... 39
11.5 "Taperings" frame ... 40
11.6 Display of the coordinates of the entered nodes ... 41
12 Chart aspect setup... 42
12.1 "Background" frame ... 42
12.2 "Graph" frame ... 42
12.3 "Evaluation standards" frames ... 43
13 Marking the positions... 44
14 Autosave function... 45
14.1 Setting Autosave parameters ... 45
15 Data filing for statistical analysis... 48
16 Program Toolbar ... 49
Index of figures
Figure 1 – Machine axes ... 5
Figure 2 – Control Panel ... 7
Figure 3 – Gear Parameters ... 8
Figure 4 – Correction factor: algebraic sign ... 9
Figure 5 – Calculation of X through Wk ... 10
Figure 6 – Measurement Limits ... 12
Figure 7 - "dfs-de" Window... 13
Figure 8 – Parameters useful for measuring profile and side ... 15
Figure 9 – Scan positions and additional options ... 16
Figure 10 – Pin centring symbol ... 18
Figure 11 - Pin alignment symbol ... 18
Figure 12 - Wk with K = 3 (applicable both to internal and external gears)... 19
Figure 13 – Measurement sheet parameters... 22
Figure 14 – Tapering values ... 24
Figure 15 - Deviations from the ideal involute... 26
Figure 16 – Deviations from the ideal helix... 27
Figure 17 - Max fp errors, max fu, Rp ... 28
Figure 18 – Fp error ... 28
Figure 19 – Fr Error... 29
Figure 20 - helix and involute ... 31
Figure 21 - division and concentricity measurement sheet ... 34
Figure 22 - Tolerance areas and taperings ... 36
Figure 23 – Nodes inside the tolerance area ... 37
Figure 24 – Joining the nodes of the tolerance area with lines ... 38
Figure 25 – Circle arc inside the tolerance area ... 39
Figure 26 – Adding a reference inside the tolerance area... 40
Figure 27 – Tapering value ... 41
Figure 28 - Tolerance area data display ... 41
Figure 29 – Chart aspect setup ... 42
Figure 30 - Best-fit line and area that encloses the trace ... 43
Figure 31 – Marking the involute/helix positions ... 44
Figure 32 - Involute marking example... 44
Figure 33 - Autosave function parameters... 45
Figure 34 – Autosave option: "No Master" ... 47
Figure 35 – Store a new SPC element... 48
1
Introduction
This program is used for controlling parallel axes gears. The following types of controls may be carried out:
Helix and Involute
Division and concentricity
Wildhaber and Distance between Pins
The GMM involute tester is a device fitted with 3 linear movements (X - Y - Z) arranged according to a set of three coordinated axes plus a fourth rotary axis (rotary table W) aligned with the vertical axis (Z).
All four axes are motor-driven and interlocked by a control board.
The workpieces to be measured are placed between two tailstocks: one located in the middle of the rotary table and the other, the height of which can be adjusted to tighten the workpiece, which is also motor-driven.
An analog type detection probe, transferred by the three linear axes, has been installed and is sensitive to one-way movements.
The machine is fitted with a PC and a printer to print the test certificates.
2
Control panel
Figure 2 shows the machine control panel.
The control buttons and selectors are described below:
ST. GEN. button
Turns on power supplies
To be turned on to enable the axes
Active each time the Measurement stage begins
PATH button Aid to measurement programming
ST. CYCLE button To start the automatic sequences
RESET PROBE button To reset the probe indicator
UP button - DOWN button To move the tailstock unit up or down
W+ button To move rotary W axis counterclockwise
W- button To move rotary W axis clockwise
Jog control X+ Moves the head towards X +
Jog control X- Moves the head towards X −
Jog control Y+ Moves the head towards Y +
Jog control Y- Moves the head towards Y −
Jog control Z+ Moves the head towards Z +
Jog control Z- Moves the head towards Z −
EMERGENCY button To stop the axes and interrupt any automatic sequence
GEARING selector
When the selector is switched to ON, paired with JOG movements X and Z, W rotates and therefore generates an involute or a helix, respectively, relative to the gear to be controlled
SPEED selector
3
Entry of initial data – Gear parameters
Figure 3 – Gear Parameters
Access, through dropdown menu File -> New, the "gear parameters" window to enter the nominal data of the gear in question:
Alfa: pressure angle
Beta: angle of the helix on the pitch diameter Helix slope (right or left)
Normal module Number of teeth Correction factor
Internal or external toothing (if this function is enabled)
After having selected the parameters, also select the sensor to be used during the measurement.
If a value of the gear identification parameters was changed, as compared to a previous measurement, option Suggest positions for different toothings permits leaving measurement values unchanged in the next windows. Otherwise values are reset.
When uploading a previously stored file, the foregoing parameters saved in the measurement will also be uploaded automatically.
On opening the program the first time, parameter data will be the same as those set before the last closing procedure.
3.1
Module or Diametral Pitch
If the value of the normal module is unknown, enter the diametral pitch value so that the normal module will be calculated automatically. Vice versa, if the module value is known, the diametral pitch is calculated automatically.
It follows that the 2 parameters are mutually exclusive: only one needs to be calculated for the measurement.
3.2
Correction factor
If the gear correction factor is unknown but the Wildhaber value is known, click "?" to convert the Wildhaber value to correction factor "X".
The figure below shows the direction of the X sign for the external and internal gears.
3.2.1
Calculating the correction factor through Wildhaber
Figure 5 – Calculation of X through WkData that was previously entered in the "Gear parameters" window is summarized in the "Gear data" frame. Data cannot be edited.
Set the Wildhaber (Wk) value inside the "Calculation" frame and also set on how many teeth it is measured (k) to obtain the correction factor (X).
On exiting from the window, the correction factor is indicated in the "Gear parameters" window.
3.3
Moment of inertia
Permits changing the inertial parameters setting in the case of very heavy gears. To be changed only after having contacted MDM technicians.
3.4
Profile development
Indicates whether the development of the involute is to be considered in diameters, in tangential runs or in rotation angles.
The choice will have consequences on the unit of measure of the Y axis in the profile graph.
3.5
Coning angle
For defining toothings with flanks having opposite direction helixes (right and left). When the coning angle is set to zero, the flanks will move in the direction of the relevant helix (the same as that set inside the "Helix slope" frame).
4
Setting the measurement limits
Figure 6 – Measurement Limits
The analog transducer reading instrument located at the top on the left-hand side displays the sensor position as compared to its rest position. The reading range is ± 0.5 mm.
The analog transducer reading instrument located below on the left-hand side displays the sensor position as compared to the relative zero (set the relative zero by pressing
the Reset Probe button on the control panel). The reading range is ± 0.05 mm.
4.1
"Profile Measurement" Frame
The positioning parameters for measuring the involute are expressed in diameters, tangential runs or rotation angles, depending on the selection made inside the "Gear Parameters" window, and include the following items:
Tip: to be set either directly or through the path procedure (see Chapter 4.5.2); this value delimits the involute scan zone towards the tip diameter.
Root: to be set either directly or through the path procedure (see Chapter 4.5.2); this value delimits the involute scan zone towards the root diameter.
Current: displays the probe's current position.
Base diameter: shows the value of the theoretical base diameter
N.B.: the Root < Tip relation is always applicable to the external gears whilst the Tip < Root relation is always applicable to the internal gears.
4.1.1
"dfs-de" button
Figure 7 - "dfs-de" Window
The involute processing start and end values may be calculated if the following quantities are known:
Gearing centre distance
Number of teeth of the coupled gear fhp hob factor
Hob radius factor
Tooth thickness minimum tolerance Tooth thickness maximum tolerance
4.2
"Z Flank Measurement" Frame
The positioning parameters for measuring the helix include:
Length B: to be set either directly or through the path procedure (see Chapter
4.5.2); this value expresses the flank length in the Z direction.
Down: to be set either directly or through the path procedure (see Chapter 4.5.2); this value delimits the helix downwards scan zone. The Length B value is added to this coordinate to delimit the helix scan zone.
4.3
"Axes" Frame
This frame displays the coordinates of the center of the probe in real time.
4.4
Number of Measurements
From 1 to 4 teeth may be set at the most.
4.5
Buttons and check-boxes
LEFT flank Automatic Pos. check-box: the procedure consists in measuring all
the right flanks of the teeth first and then all the left flanks.
If the check-box is enabled, the involute tester will measure the left flanks without asking the operator for the go-ahead, calculating a tooth thickness through the correction factor entered in the "Gear parameters" window. Otherwise, the machine will stop adjacent to the left flank so that the operator may turn the gear to allow the probe to enter the tooth space (this option is recommended if the correction factor is unknown).
Measurement button: for accessing the next dialog window and measuring the
gear (see Chapter 5). This button is active only after having reset the machine (see "Home" button).
Home button: for calling up the involute tester resetting procedure (see Chapter
4.5.1); this procedure is required each time the Personal Computer is rebooted. After this procedure, the origin of the { X,Y } axes, integral with the center of the probe, will match the tailstocks' axis.
Db Set button: moves the machine's Y axis tangential with the base circle, so
that the path procedure is used (see Chapter 4.5.2).
Abort button: aborts any automatic procedure in progress.
Exit button: to exit from the current dialog window.
4.5.1
Resetting procedure
Always reset the axes after having turned on the machine. Proceed as follows to start the HOME procedure:
Make sure that there aren't any messages inside the emergencies box (the only admissible exception is the TAILSTOCK OPEN message).
Use the jog control to move the axes near zero. Press the Home button (buttons area).
Press the Start Cycle button (control panel). Wait until the procedure is finished.
N.B.: Carry out the Home procedure only once, on turning on the machine. As such, there is no need to repeat it before carrying out all the subsequent measurements.
4.5.2
PATH Procedure
Position the head above the lead length, press the DbSet button (buttons area), the Start Cycle button (control panel) and wait until the Y axis is on the base radius. N.B.: Since the y axis must maintain this position throughout the procedure, do not move the jog Y.
Insert the head into a tooth space, turn the W axis slowly until the head is pre-loaded by about 0.1 mm and then press the RESET PROBE button (control panel).
Position the cursor inside the Tip box of the positioning parameters to measure the involute, clicking on it with the mouse.
Switch the GEARING control panel command to ON.
Move the head until it reaches the tip of the tooth using jog x and then press the PATH button (control panel).
Move the head until it reaches the root of the tooth using jog x and then press the PATH button (control panel).
Move the head to the beginning of the helix, bottom side, using jog z- and then press the PATH button (control panel).
Move the head to the end of the helix, top side, using jog z+ and then press the PATH button (control panel).
N.B.: A sound is heard each time the PATH button is pressed.
5
Scan positions and additional measurement
options
Figure 9 – Scan positions and additional options
In this dialog window the user may change the positions and measurements that the program sets by default.
5.1
Helix-Involute positioning and measurement
By default, the measured teeth are equally distributed 360° beginning from tooth number 1, which corresponds to the first one the probe finds on its path on the way to the workpiece.
There is a frame on the left-hand side of the dialog window (see Fig. 9) that displays measurement positioning information, specifically:
tooth number (beginning from the first one detected) positioning of the involute (Z distance)
positioning of the helix: defined in diameters/tangential run/rotation angles depending on the selection made inside the "Gears Parameters" window (see Chapter 3).
The positioning of the involute is set by default as the mean of the "Tip"-"Root" values entered inside the dialog window before this one (see Chapter 4), whilst the positioning of the helix is defined as "Bottom" + "Length B"/2.
These default values are set with the "Standard settings" check-box enabled. Disable "Standard settings" to change the foregoing values.
5.1.1
Automatic lead search B
When this option is active, the "Bottom" parameter entered inside the window before this one (see Chapter 4) will no longer have any significance. In fact, the involute tester will automatically search for the lead and will use, as useful helix length, the "Length B" value centered in this lead.
N.B.: the involute tester's first movement will be to shift to search for the workpiece. As such, it is important that on pressing the Start Cycle button on the control panel, the height of the probe should be included in the lead's length.
5.1.2
Measuring the RIGHT flanks only
When this option is enabled, only the right flanks of the tooth being examined will be measured.
5.1.3
Involute Measurement through 3-Axes GMM
When measuring the involute the machine's kinematism consists of a shift along the X axis equivalent to the tangential run of a circle having a diameter equal to the base diameter of the gear.
There are cases, especially for internal gears, in which this movement is inhibited by the area of the probe's stem. This problem is solved by carrying out the measurement with X = 0 (moving Y and W only) and enabling the "Involute measurement by 3-Axes GMM" check-box.
5.1.4
Disable Helix measurement – Disable Involute measurement
Use these options to measure only the helix or only the involute of the tooth.
Even if one of the two measurements is excluded, the Tip, Root, Bottom and Length B
parameters entered inside the dialog window before this one (see Chapter 4) must in any case be set correctly (if, for instance, the user disables the involute measurement,
Tip and Root are used to determine at which diameter the helix is measured).
5.2
Determining workpiece axis
In this frame the user defines the workpiece axis to carry out the measurements according to a reference system integral with said axis.
One or both of the following options may be used (Chapter 5.2.1 and Chapter 5.2.2). In both cases the following values must be entered:
increased height and diameter of section C1 (pin down). increased height and diameter of section C2 (pin up). increased diameter of section C3 (gear max area).
N.B.: concerning internal gears, only one centring correction has been foreseen. This is why sections C1 and C2 must match (same height and diameter).
5.2.1
Centring on pins
To be used if the toothing is not aligned with the workpiece reference marks (runout correction).
The symbol shown in Fig. 10 appears on the measurement sheet when the measurement is carried out using this option.
Figure 10 – Pin centring symbol
5.2.2
Alignment on pins
To be used to correct any misalignments along the Y axis of the involute tester tailstocks.
The symbol shown in Fig. 11 appears on the measurement sheet when the measurement is carried out using this option.
5.3
Pitch positioning and measurement
The following elements may be measured in addition to the helix and the involute: Division and concentricity (necessary for the "Wildhaber" measurement) Wildhaber (necessary for the "Distance between pins" measurement) Distance between pins
The helix and involute measurements may be excluded by enabling the "Measure only
the Pitch and/or the Wk" option (see Fig. 9).
5.3.1
"Division and concentricity" frame
Click the Measurement check-box to enable the measurement of the division (see Fig. 9).
Edit the diameter at which to carry out the measurement in Measurement Diam. or click the Pitch Diam. button to carry out the measurement at the pitch diameter.
In any case the value must be included between the Foot and Head values specified inside the dialog window before this one (see Chapter 4).
The measurement is carried out at a Z distance equivalent to "Bottom" + "Length B"/2 (see Chapter 4).
If the hobbing Px value is other than zero, the pitch between one tooth and the next will be measured by changing the Z distance by an amount equal to the hobbing Px/number of teeth.
5.3.2
"Teeth k deviation control" frame
In order to measure the Wildhaber, enable the Measurement option inside the "Teeth k deviation control" frame, specifying the k value or using the default value for it, by clicking the Set default button.
Specify the number of measurements to be carried out inside the "N." frame (equally distributed 360°).
If the number of measurements is greater than 1, the maximum, minimum and mean Wk will be supplied.
Only the mean Wk is displayed if the "Distance between Pins" is also required.
N.B.: the Wildhaber may be measured only with the "Division and concentricity" option enabled.
5.4
Starting the measurement
Press the OK key to exit from the dialog window and begin the measuring procedure (after having pressed the St.Cycle button on the control panel).
6
Measuring a gear
Proceed as follows:
6.1
Measuring a non-stored gear
1. Select the New option of the File -> New menu.
2. Enter the parameters of the toothing to be controlled (see Chapter 3).
3. Once the configuration has been confirmed, the measurement window is displayed (see Fig.6).
4. Make sure that there aren't any messages inside the emergencies box (the only one allowed is TAILSTOCK OPEN).
5. Mount the gear to be controlled in between the tailstocks using the UP and DOWN buttons on the control panel. The centre's downward movement stops automatically once it has been clamped and the "TAILSTOCK OPEN" message will be cleared from the emergencies box.
6. Enter the positioning values inside the dialog window (see Chapter 4).
7. Press the Measurement key to display the dialog window of Fig.9. Set the required values (see Chapter 5) and press OK.
8. Press the Start Cycle button on the control panel. The axes reach the starting position automatically.
9. Wait until the procedure is finished. If a stop is required to change flanks, message "PRESS START CYCLE TO BEGIN THE MEASUREMENT" is displayed after having measured the right flanks. Press to continue and wait until the measurement is finished.
10.Remove the gear from the tailstocks (UP button on the control panel). 11.Press the EXIT key inside the dialog window of Fig.6.
6.2
Measuring a stored gear
1. Select the Open option of the File -> Open menu. 2. Select the file of the gear to be controlled. 3. Select the New option of the File -> New menu.
4. Confirm the toothing parameters.
5. Make sure that there aren't any messages inside the emergencies box (the only one allowed is TAILSTOCK OPEN).
6. Mount the gear to be controlled in between the tailstocks using the UP and DOWN buttons on the control panel. The centre's downward movement stops automatically once it has been clamped and the "TAILSTOCK OPEN" message will be cleared from the emergencies box.
7
Measuring sheet parameters
Figure 13 – Measurement sheet parameters
After having carried out the measurement and having pressed the Exit key, the
Measuring sheet parameters window is displayed inside which to set all data useful for
viewing the graphs and evaluating the measurements.
This window may be brought up at any time through the Modification
SheetParameters menu or using the icon that looks like 2 sheets, present at the top.
7.1
"Profile Limits" frame
The user may set Tip and Root values lower than those set before beginning the measurement. These changes will influence the errors and, consequently, the measured class.
Values are expressed as diameters/tangential runs/rotation angles, depending on the choice made when the initial setting of the measurement had been made (see Chapter 3.4).
The user may convert the data inside the displayed unit of measure through the keys located next to the relative boxes ( ).
The profile graph is developed on an XY plane where X represents the error and Y represents the diameters or tangential runs or rotation angles.
The X axis scale may be changed through the Err. Scale parameter whilst the Y axis scale may be changed through the Y Scale parameter.
N.B.: the Y Scale may be changed only if the "Y Scale automatic calculation" option is not set in the "Display and evaluation" window (see Chapter 12.2).
Buttons 80% and 90% are for setting the involute length, subjected to evaluation, to said analyzed involute percentage.
7.2
"Z flank limits" frame
The user may set Bottom and Top helix length values lower than those set before beginning the measurement. These changes will influence the errors and, consequently, the measured class.
It is important to keep in mind that the values set inside this window are relative to those set before beginning the measurement (which are instead absolute values in Z axis).
For example:
let's call Bottom_A and Top_A the absolute values in Z axis to differentiate them from the relative Bottom and Top values.
Therefore:
Bottom = distance_in_z – Bottom_A
if the following value had been set on setting the measurement (see Chapter 4)
Bottom_A = 13 and Length B = 10
this means that
Bottom_A = 13 and Top_A = 13 + 10 = 23;
then Bottom = 0 inside this dialog window will correspond to an absolute distance in z equivalent to distance_in_z = Bottom + Bottom_A = 0 + 13 = 13.
The profile graph is developed on an XY plane, where X represents the error and Y represents the helix length.
The X axis scale may be changed through the Err. Scale parameter whilst the Y axis scale may be changed through the Y Scale parameter.
N.B.: the Y Scale may be changed only if the "Y Scale automatic calculation" option is not set in the "Display and evaluation" window (see Chapter 12.2).
Buttons 80% and 90% are for setting the helix length, subjected to evaluation, to said analyzed helix percentage.
7.3
"Profile classes" frame
Use the fields present inside this frame to change the nominal classes of the profile evaluation parameters.
If the "Customize" option was set inside the "Display and evaluation" window for the profile evaluation standard (see Chapter 12.3), press the Customize button to set the tolerance limits.
7.4
"Flank classes" frame
Use the fields present inside this frame to change the nominal classes of the flank evaluation parameters.
If the "Customize" option was set inside the "Display and evaluation" window for the flank evaluation standard (see Chapter 12.3), press the Customize button to set the tolerance limits.
7.5
"Division and concentricity" frame
Use the fields present inside this frame to change the nominal classes of the pitch evaluation parameters.
If the "Customize" option was set inside the "Display and evaluation" window for the division evaluation standard (see Chapter 12.3), press the Customize button to set the tolerance limits.
The division graphs are developed on an XY plane, where X represents the number of the tooth and Y represents the pitch error.
The error scale may be changed through the Err. Scale parameter.
7.6
"Taperings" frame
If tapering beginning and end lines were defined (see Chapter 11.5), tolerance values may be set and the tapering values may be displayed on the sheet by clicking the Display Values check-box.
The taperings value is displayed at the bottom of the graph (in black if the value is within tolerance and in red if beyond set tolerance).
7.7
Distance between pins calculation
If the Wildhaber-Wk was measured (see Chapter 5.3.2), the distance between pins may be displayed on the "division and concentricity measurement sheet" (see Chapter 10). This is done by enabling the Mdk option and setting the pins' diameter inside the Diameter field (value in mm).
7.8
Crowning
A crowning may be set or displayed both on the helix and the involute.
Select Crowned Flank and/or Crowned Profile. To set a crowning, key in the µm value inside the field next to it. If the crowning is to be calculated, key in 0 inside the adjacent field.
The crowning value (set or calculated) is displayed inside the "Involute measurement and tooth direction sheet" inside the line called "ca" (see Fig. 20).
7.9
Identification data
The user may enter any string inside the following fields: Type of gear Drawing Lot Customer Filing code Operator
that will later be noted down inside the measurement sheets (see Fig. 20 and 21). These strings may be used in the automatic save procedure (see Chapter 14).
If the "Obscure construction data" check-box is set, the gear parameters will not appear in the measurement sheet.
7.10
Machine corrections
The User def. list and User def. rec fields are used to upload certain parameters, supplied by the user, for calculating corrections in gear-cutting machines.
Further to helix and involute errors, the values to be set in the gear-cutting machines are consequently calculated to improve quality.
8
Parameters that define quality
Parameters that define the quality of a gear are defined through errors that represent the deviation of the measurement from the ideal trend.
8.1
Profile quality parameters
The profile's ideal trend is represented by a straight vertical line.
Each deviation from the foregoing line represents a deviation from the ideal profile. There are 3 types of profile errors:
fHαααα: Profile slope deviation. Fαααα: Total profile deviation. ffαααα: Profile form deviation.
The following graph provides an explanatory example.
Figure 15 - Deviations from the ideal involute
8.2
Flank quality parameters
The flank's ideal trend is represented by a straight vertical line.
There are 3 types of flank errors:
fHββββ: Helix slope deviation. Fββββ: Total helix deviation. ffββββ: Helix form deviation.
The following graph provides an explanatory example.
Figure 16 – Deviations from the ideal helix
8.3
Division and concentricity quality parameters
The division errors graphs are represented by histograms. The height of the histogram represents the detected error.
Detected errors are as follows:
fp max: Max single division error. fu max: Max pitch skip.
Rp: Division rejection. Fp: Division sum error. Fp z/8: Partial sum error.
Fr: Concentricity error. Rs: Tooth thickness change.
The graphs displayed in the measurement sheet (see Fig. 21) are as follows:
Single division error fpi for the left and right flanks (or Single pitch deviation): the i-th histogram represents the pitch error between the flank (right or left) of tooth "i" and the flank (right or left) of tooth "i + 1".
The max absolute value error is the fp max error.
If Si= |fp i+1 – fpi |(i.e. the difference between one histogram and the next in absolute
value), then fu max = max { Si }[ i = 1..z ].
If M = max {fpi }[ i = 1..z ] and m = min { fpi }[ i = 1..z ] (where the max and min values are
intended to be algebraic, i.e. calculated taking the signs into account), then Rp = M –
m (which is practically the difference between the graph's highest and lowest histograms).
Figure 17 - Max fp errors, max fu, Rp
Division sum error Fpi for the left and right flank (or Cumulative pitch deviation): the i-th histogram represents the pitch error between the flank (right or left) of the first tooth and the flank (right or left) of tooth "i + 1" (which is the same as doing the algebraic sum of the single division errors, Fpi = Σfpk [ k = 1..i ]).
If M = max { Fpi }[ i = 1..z ] and m = min { Fpi }[ i = 1..z ] (where the max and min values are
intended to be algebraic, i.e. calculated taking the signs into account), then Fp = M –
m (which is practically the difference between the graph's highest and lowest histograms).
If Fi + 8is the pitch error between the flank (right or left) of tooth "i" and the flank (right or left) of tooth "i + 8", then Fp z/8 = max { Fi + 8 }[ i = 1..z ].
One may obtain the teeth's change in thickness from the cumulative errors of the right and left flank pitches. The maximum of these changes is Rs.
Concentricity measurement (Runout):
the difference between the highest and lowest histogram is the Fr error.
Figure 19 – Fr Error
8.4
Classes and evaluation standards
The quality of a gear is identified by the membership class.
Each class is characterized by a max admissible error (called tolerance limit). The lower the numeric identifier of a class, the higher the quality.
In order to determine the membership class of a parameter, the user must find the class with the tolerance limit that is nearest and higher than the value of the affected parameter.
Classes and tolerance limits vary according to the evaluation standard. The program includes 3 types of evaluation standards:
ISO 1328 DIN 3962 AGMA 2015
See Chapter 12.3 to change the adopted evaluation standard.
The following tables specify, for each parameter, the classes available for each evaluation standard.
Table of classes available for helix and involute parameters Standard
Parameter
ISO 1328 DIN 3962 AGMA 2015
fHαααα 0, 1, 2, ….12 1, 2, 3, ….12 A2, A3, A4, …. A12 Fαααα 0, 1, 2, ….12 1, 2, 3, ….12 A2, A3, A4, …. A12 ffαααα 0, 1, 2, ….12 1, 2, 3, ….12 A2, A3, A4, …. A12 fHββββ 0, 1, 2, ….12 1, 2, 3, ….12 A2, A3, A4, …. A12 Fββββ 0, 1, 2, ….12 1, 2, 3, ….12 A2, A3, A4, …. A12 ffββββ 0, 1, 2, ….12 1, 2, 3, ….12 A2, A3, A4, …. A12
Table of classes available for division and concentricity parameters Standard
Parameter
ISO 1328 DIN 3962 AGMA 2015
fp max 0, 1, 2, ….12 1, 2, 3, ….12 A2, A3, A4, …. A12
fu max -- 1, 2, 3, ….12 --
Rp -- -- --
Fp 0, 1, 2, ….12 1, 2, 3, ….12 A2, A3, A4, …. A12
Fp z/8 0, 1, 2, ….12 1, 2, 3, ….12 --
Fr 0, 1, 2, ….12 1, 2, 3, ….12 C2, C3, C4, …. C12
9
Helix and involute measurement sheet
Figure 20 shows an example of a helix and involute measurement sheet.
View the sheet through the Display -> Involute and Helix Graph menu or the corresponding icon:
The first part of the sheet shows the gear parameters and identification data (see Chapter 7.9) followed by the profile graph and the flank graph.
In order to modify the evaluation limits or the nominal classes at any time, modify the sheet parameters (see Chapter 7). In order to modify that which is displayed and the evaluation standards, modify the graph parameters (see Chapter 12).
9.1
Profile graph
The profile graph shows the traces of the measured right and left flanks. The number of the corresponding tooth is on top of each trace.
The red segments identify the profile evaluation zone. The numeric values of said limits are indicated adjacent.
Limits are indicated with 2 different units of measure on the right and left-hand side of the sheet. They are indicated on the right in the unit selected to enter the gear parameters (see Chapter 3). In any case one of the 2 is always displayed in diameters. The graph's scales are also shown on the left-hand side, the error scale at the top and the profile development scale at the bottom.
N.B.: if the development of the profile chosen for the measurement were in diameters, the scale would in any case refer to the shift as compared to the center of the gear. Therefore if for instance the scale were 1 mm, one square would contain a diameter development equivalent to twice the scale, i.e. 2 mm.
The detected errors and the corresponding membership classes are indicated underneath the graph.
Symbol Qn indicates the nominal classes whilst Qr the detected classes. If the detected class is greater than the nominal one, it is displayed in red.
In addition to the detected errors, there is a line reserved to the detected or set crowning (marked by letters "ca") and another line for the mean fHαααα value.
9.2
Helix graph
The helix graph shows the traces of the measured right and left flanks. The number of the corresponding tooth is on top of each trace.
The red segments identify the helix evaluation zone. The numeric values of said limits are indicated adjacent.
The graph's scales are also shown on the left-hand side, the error scale at the top and the helix length scale at the bottom.
The detected errors and the corresponding membership classes are indicated underneath the graph.
Symbol Qn indicates the nominal classes whilst Qr the detected classes. If the detected class is greater than the nominal one, it is displayed in red.
In addition to the detected errors, there is a line reserved to the detected or set crowning (marked by letters "ca") and another line for the mean fHββββ value.
10
Division and concentricity measurement
sheet
Figure 21 shows an example of a division and concentricity measurement sheet.
View the sheet through the Display -> Division and Concentricity Graph menu or the corresponding icon:
The first part of the sheet shows gear parameters, identification data (see Chapter 7.9), the Wildhaber measurement and the distance between pins (if measured). It contains 5 graphs:
Single division error of the left flank Division sum error of the left flank Single division error of the right flank Division sum error of the right flank Concentricity error
The graph's scales are shown on the left-hand side whilst the detected errors and the corresponding membership classes are underneath the graphs.
Symbol Qn indicates the nominal classes whilst Qr the detected classes. If the detected class is greater than the nominal one, it is displayed in red.
In order to modify the evaluation limits or the nominal classes at any time, modify the sheet parameters (see Chapter 7). In order to modify that which is displayed and the evaluation standards, modify the graph parameters (see Chapter 12).
11
Tolerance areas (K Area) editor and
Taperings
After having carried out the measurement, a tolerance area may be set on the helix and involute graphs.
4 different types of tolerance may be set through the following menus:
Modify -> Tolerance areas editor and Taperings -> Left flank profile Modify -> Tolerance areas editor and Taperings -> Right flank profile Modify -> Tolerance areas editor and Taperings -> Left flank helix Modify -> Tolerance areas editor and Taperings -> Right flank helix
The following dialog window is displayed after having selected the type tolerance:
Figure 22 - Tolerance areas and taperings
Use the white window on the left-hand side with an active cursor (a red cross) to draw the tolerance area.
Create the area by first drawing some dots (nodes) and then joining the dots with lines or circle arcs.
The X axis of the graph, the unit of measure of which is µm, is the admissible error (the tolerance). The Y axis represents, in the case of the involute, the development of the profile (in tangential runs, diameters or rotation angles depending on the measurement choice made). The Y axis represents the helix length in the case of the helix.
The positioning of the tolerance area along the Xs axis has no importance at all since the program automatically positions the area on the detected trace. As such, only the positioning along the Ys axis is important.
11.1
Inserting the nodes
First of all insert the dots that delimit the tolerance area.
The positioning of the cursor inside the white area is highlighted at the top on the right-hand side (X and Y coordinates). In order to insert a node, click the mouse inside the required dot or enter the values directly at the top on the right-hand side inside editable fields X and Y and then press the "Add node" button.
Use button next to the Y field to convert coordinate Y from other units of measure (diameters, tangential runs or rotation angles) to the one used in the measurement. If a mistake is made, simply click the mouse adjacent to the wrong dot and press "Delete dot".
11.2
Joining nodes to lines or circle arcs
Once the nodes have been defined, simply press the "Line" button and follow the directions inside the frame at the bottom to join the dots (in practice, click the mouse near the dots to form the required lines).
N.B.: to join 3 dots, press the "Line" button only once and then click in sequence near the 3 nodes.
Figure 24 – Joining the nodes of the tolerance area with lines
3 dots are needed to form a circle arc: arc start dot, central dot and arc end dot. In order to create the arc, press the "Circle" button and then the 3 foregoing dots in sequence.
Figure 25 – Circle arc inside the tolerance area
11.3
Specular tolerance area
After having created a tolerance area for one flank (whether right or left), the area created for the opposite flank is shown when the area for the other flank is created. If the area to be defined is the mirror image of the previously entered one, simply press the "Turn over mirror-like" button otherwise press "Delete all" to delete the current area and create a different one.
11.4
Reference node inside the tolerance area
As stated above, the program automatically positions the area onto the detected trace but the positioning may be forced through the "Add reference" button.
By adding a reference node the trace will be forced to cross that dot.
Press the mouse on the required dot or enter coordinates X and Y at the top on the right-hand side and then press the "Add reference" button.
Figure 26 – Adding a reference inside the tolerance area
11.5
"Taperings" frame
The "Taperings" frame is active only for the profile.
Given two horizontal lines on the profile graph, the tapering is nothing other than the distance, in X, of the dots intersecting the lines (see figure below).
Figure 27 – Tapering value
Set the tapering start and end lines by clicking the mouse at the required Y coordinate (in any X position) or edit the value directly and then press Tapering Start or Tapering End. The zone between the beginning and the end of the tapering is gray. (For the display see Chapter 7-7.6.)
11.6
Display of the coordinates of the entered nodes
After having created a tolerance area, the user may view the coordinates of the entered nodes at any time through the Display -> K Area Data menu option or with the following icon: .
Figure 28 - Tolerance area data display
If the nodes are too near to one another, the coordinates might overlap partially. To ward off this problem, change the graph display scales (Y Scale and/or error Scale).
12
Chart aspect setup
Access the dialog window "Chart aspect setup" via the Modify -> Graph parameters menu or the icon.
Figure 29 – Chart aspect setup
12.1
"Background" frame
The background may be changed from the millimeter sheet to white, passing through a stippled background.
12.2
"Graph" frame
In addition to the measurement trace, the best-fit line and the area that encloses the entire trace (a parallelogram with sides parallel to the best-fit line that contains every point of the curve) may also be viewed.
The following figure shows the same trace, first with no additional graph, then with the addition of the best-fit line and lastly with the addition of the area that encloses the trace.
Figure 30 - Best-fit line and area that encloses the trace
If a tolerance area was set (see Chapter 11) using the "Show diagram k only" option, the best-fit lines and trace-containing areas will be excluded from that displayed.
The "Y Scale automatic calculation" option sets the best Y Scale for viewing the trace (also see Chapters 7.1 and 7.2).
12.3
"Evaluation standards" frames
The following measurement evaluation standards may be changed inside these frames: DIN 3962 (see Chapter 8.4).
ISO 1328 (see Chapter 8.4). AGMA 2015 (see Chapter 8.4).
None: shows the graph only and excludes the measurement and quality values. Exclude quality: shows the measurement values only and excludes the detected quality.
13
Marking the positions
Access the "Involute/helix positions marking" dialog window through the Modify ->
Markings menu or through icon .
Figure 31 – Marking the involute/helix positions
Use this window to mark certain positions on the graph (of the profile or helix).
Specify the unit of measure in "Involute marking" with which the position on the profile is specified.
Specify the position of the marking and the label to be displayed inside the Involute and Helix frames.
When View is ticked, the label will be displayed on the graph (see figure below). Figure 32 - Involute marking example
14
Autosave function
A measurement may be saved in the usual manner through the "File -> Save" or "File ->
Save with name…" menu or with the relative icon .
As an alternative, use the Autosave function that saves the file inside preset folders with names defined through specific parameters, specifically with that which had been entered in 2 of the identification fields that may be edited in the Sheet parameters
section (see Chapter 7.9).
The foregoing 2 fields must univocally identify the type of measured gear: two measurements having 2 matching identification fields represent the same gear.
The measurements of the same gear are saved inside the same folder with different names that indicate the day and time in which the measurement was carried out.
The first time (and only the first) that a specific type of gear is measured, which had never been measured before, and therefore not present inside the archive, another copy of the file, called "master file", will be saved inside a different folder.
A measurement may be saved with the Autosave function through menu "File ->
Autosave" or with the relative icon .
14.1
Setting Autosave parameters
In order to set the autosave parameters, use the Modify -> Autosave Setup menu.
Figure 33 - Autosave function parameters
The dialog window contains two frames: Modify parameters and Autosave structure. The current setting of the parameters is displayed inside Autosave structure whilst they may be modified in Modify parameters.
A modification inside the Modify parameters frame will lead to a change inside the
Autosave structure frame in real time.
The Autosave function is based on 2 parameters that may be chosen among those that identify the gear (see 7.9). These 2 parameters may be selected through Level 2 and
Level 3 of the Modify parameters frame.
An autosave folder is created through the settings shown in Fig. 33 inside which 2 folders
will be created: master and measure. A folder with a name that is the same at that which had been entered inside the Customer identification field will be created in each of the foregoing 2 folders. A folder will be created inside, with a name that is the same as the one that had been entered inside the File code identification field, inside which the files will be saved.
The name of these files will depend on how the File name field of the Modify
parameters frame was set. With the setting shown in Fig.33, the name will contain the
day and time in which the measurement was carried out.
The name of the "master file" will be the same as the one that was entered inside the
File code identification field.
For example:
If on April 21st, 2009 at 12:30 a gear is measured and "MDM-Mecatronics" is entered inside the Customer identification field, and "579-001" is entered inside the File code
field, the autosave function creates the following files:
C:\autosave\master\MDM-Mecatronics\579-001\579-001.fee master file
C:\autosave\measure\MDM-Mecatronics\579-001\21Apr09_1230.fee
If the same gear is measured (the user does not change that which had been entered inside the Customer and File code identification fields) at 12:45 of the same day, the autosave function will add the following file only:
C:\measure\MDM-Mecatronics\579-001\21Apr09_1245.fee
To delete Level 2 or Level 3 from the master file structure, click the corresponding "No Master" option (see figure below).
Figure 34 – Autosave option: "No Master"
In order to change the active logic unit ("C" by default), click at the bottom on "Change active logic unit" and select the required one.
15
Data filing for statistical analysis
Measurement data may be filed for future statistical analyses: go to the SPC -> Save
menu or use icon .
Figure 35 – Store a new SPC element
Enter a name in File name and press Add. Press Reset to create a new file.
Press button to change target path.
Select the QS-Stat check-box to create a file that may be used by Q-DAS' QS-Stat program.
N.B.: this function is only a statistical program-based interface and does not run statistical analyses.
16
Program Toolbar
This is the program's toolbar.
Figure 36 - Toolbar
The toolbar in Fig. 36 contains:
1: To set a new measurement (see Chapter 3). 2: To open a stored file.
3: To save a measurement.
4: To save the graph in Pcx image format.
5: To modify the sheet parameters (see Chapter 7). 6: To mark the positions (see Chapter 13).
7: Graph display and evaluation (see Chapter 7). 8: To print the graph.
9: GearSoft info.
10: To view the helix and involute measurement sheet (see Chapter 9).
11: To view the division and concentricity measurement sheet (see Chapter 10). 12: To view machine parameters.
13: To view K Area data (see Chapter 11.6). 14: To file SPC data (see Chapter 15). 15: Autosave function (see Chapter 14).
17
Machine warning messages
MESSAGE DESCRIPTION SOLUTION
Head overloaded
The sensor is beyond its safety stroke. A buzzer starts ringing at the same time this message is displayed and the axes lock.
Any automatic procedure is aborted.
Move the axes using the jog control to discharge head pressure.
Emergency button pressed
The red button on the control panel is pressed: this disables the motors and closes the air supply.
Any automatic procedure is aborted.
Restore button contact by turning it clockwise.
Tailstock open
The gear support pin is not inserted or tightened properly.
Gear measurement is enabled in any case.
Press the DOWN button on the control panel until the message is cleared.
Axes disabled
Motor drivers are disabled. If movements are to be enabled, press the ST. GEN. button on the control panel. Not enough air
pressure
Air supply pressure has dropped to below the safety values, disabling the motors.
Any automatic procedure is aborted.
Check the pressure gauge and then the feed system.
Drivers alarm
One of the drivers is in alarm state. Any automatic procedure is aborted.
Wait 10 seconds, press the ST. GEN. button on the control panel and check the signals inside the electric panel.
If the problem persists, contact technical service.
Axes limit stop One of the axes has reached its limit stop.
Set the axis back to its stroke limits using the jog control.
Servo Error
One of the axes' routine movements has run into an obstacle and this disables the motors.
Any automatic procedure is aborted.
Check both the cleanliness of the granite on which the axis slides as well as air pressure. If the problem persists, contact technical service.
