Precision Target Wheel zax / zfx
- 40 years of experience in the manufacture of precision target wheels
- Precision target wheels for attachment to shafts with a shaft diameter from 8 mm to over 500 mm
- Generation of a reference signal by reference mark (tooth or flag)
- Ferromagnetic target wheels make possible contactless magnetic scanning by a sensor with magnetoresistive sensor elements and therefore the generation of the required output signals for rotational speed and position acquisition
- Possible to manufacture target wheels for rotational speed and position acquisition using eddy currents
- Complete manufacture with bores, threads and slots
- Number of teeth: 25 to 1024
- Modules: 0.3; 0.5; 1.0; 1.25; 1.50; 1.75; 2.0; 2.25
- Standard material: 16MnCr5, stainless steel optional
- Individual inside diameter optionally with feather keyway to prevent movement in relation to the shaft
- Number mounting variants (shrinking, clamping, bolting in place mounting)
- Possible to prevent movement in relation to the shaft using feather keyway
- Multifunctional design makes it possible to use the target wheel as a bearing cover or shaft nut
- High design flexibility due to custom manufacture
- Highest precision due to usage of the latest hobbing machines or turning-milling centres
- Machine tool engineering
- Railway rolling stock
- Torque motors
Description
For the measurement of rotary movements, rotational speed
and position sensors form a unit together with target wheels.
Especially on spindles for machine tools, the sinusoidal output
signals are highly interpolated. To obtain optimal output
signals, target wheels must be manufactured with high precision
for this application. Only in this way can the output
signals from the sensors be generated in the necessary
quality.
High precision standard target wheels made of ferromagnetic
steel with module 0.3, 0.5 and 1 are available ex-works
on short delivery times.
Usage with MiniCoder GEL 2442, 2443, 2444 and 2432
MiniCoders scan target wheels with module 0.3; 0.5 or 1.
Square-wave signals with 5 V DC, 10...30 V DC or 1 Vpp
signals (sin/ cos-shaped track signals) are generated as output
signals.
The target wheels are optionally equipped with a reference
flag, a reference groove or a reference tooth. Depending on
the version or position of the reference mark, a different
MiniCoder variant is used to ensure a defined position for the
reference signal in relation to the track signals.
Maximum rotational speed
Size, inside diameter and design of the target wheel define
the strength and the maximum permitted rotational speed.
In your enquiries please state the maximum rotational speed
at which the related target wheel is to be used. We will then
assess the feasibility.
In certain cases we undertake calculations using the
FEM(1).
Depending on the application and sensor used, target
wheels with different modules are used.
The module is a tooth parameter for tooth wheels and describes
the relationship between the number of teeth and the
pitch circle diameter of the tooth wheel.
For the majority of applications the amount of space available
is limited, here the outside diameter is crucial.
The following applies:
da = Outside diameter
m = Module
z = Number of teeth
Given the same number of teeth, the smaller the module the smaller outside diameter.
Typical rotational speed range for target wheels as a function of the inside diameter and reference mark
Number of teethz | Modulem | Inside diameter di [mm] | Outside diameter da [mm] | Reference mark, referencesignal | Maximum rotational speed(a)nmax [1/min] |
64 | 0.5 | 23 | 33 | Z | 90,000 |
64 | 0.3 | 10 | 19.8 | Z | 140,000 |
128 | 0.3 | 20 | 39 | N | 30,000 |
128 | 0.3 | 17 | 39 | M | 42,000 |
256 | 0.3 | 12 | 77.8 | Z | 50,000 |
256 | 0.3 | 50 | 77.8 | Z | 40,000 |
512 | 0.3 | 20 | 154.2 | Z | 18,000 |
512 | 0.3 | 125 | 154.2 | Z | 25,000 |
(a) Bores, thread, feather keyways not taken into account
Description
Reference marks can be designed as a tooth, groove or flag.
The flag must be made of ferromagnetic material and must
not protrude beyond the tip circle of the target wheel.
The selection of the reference mark is defined by the size
and rotational speed of the target wheel used, as both parameters
have an effect on the forces acting on the reference
mark. In case of new designs we recommend the usage of
a target wheel with reference mark variant "Z".
ZAN / ZFN = Reference mark - flag
ZFM = Reference mark - groove
ZAZ / ZFZ = Reference mark - tooth
Depending on the reference mark, target wheels have the following item numbers as identifiers:
Standard target wheels
ZANxxxx Reference mark as flag (reference flag is between two teeth)
ZAZxxxx Reference mark as tooth (reference tooth is aligned with a tooth)
Custom target wheels
ZANxxxx Reference mark as flag (reference flag is between two teeth)
ZAMxxxx Reference mark as groove (reference groove is between two teeth)
ZAZxxxx Reference mark as tooth (reference tooth is aligned with a tooth)
The target wheels are marked with item number and serial number.
Standard target wheels
Available ex-works on short delivery times
Dimensional drawing standard target wheels with reference mark tooth - ZAZ
Design of standard target wheels ZAZ
Number of teethz | Modulem [mm] | Outside ø da [mm] | Inside ø di min [mm] | Inside ø di max. [mm] | Shoulder ø dr [mm] |
100 | 0.5 | 51.0 | 12 H7 | 30 H7 | 48 |
125 | 0.5 | 63.5 | 12 H7 | 40 H7 | 60.5 |
128 | 0.5 | 65.0 | 12 H7 | 40 H7 | 62 |
200 | 0.5 | 101 | 12 H7 | 70 H7 | 98 |
256 | 0.5 | 129 | 12 H7 | 90 H7 | 126 |
250 | 0.3 | 75.6 | 12 H7 | 45 H7 | 72.6 |
256 | 0.3 | 77.4 | 12 H7 | 50 H7 | 74.4 |
360 | 0.3 | 108.6 | 12 H7 | 70 H7 | 105 |
Standard target wheels
Available ex-works on short delivery times
Dimensional drawing standard target wheels with reference mark flag - ZAN
Design of standard target wheels ZAN
Number of teethz | Modulem [mm] | Outside ø da [mm] | Inside ø standard [mm] | Inside ø di max. [mm] | Shoulder ø dr [mm] |
100 | 0.5 | 51.0 | 12 H7 | 30 H7 | 47 |
125 | 0.5 | 63.5 | 12 H7 | 40 H7 | 60 |
128 | 0.5 | 65.0 | 12 H7 | 40 H7 | 61 |
200 | 0.5 | 101.0 | 12 H7 | 70 H7 | 97 |
250 | 0.3 | 75.6 | 12 H7 | 45 H7 | 72 |
250 | 0.5 | 126.0 | 25 H7 | 85 H7 | 122 |
256 | 0.3 | 77.4 | 12 H7 | 50 H7 | 74 |
256 | 0.5 | 129.0 | 25 H7 | 90 H7 | 125 |
360 | 0.3 | 108.6 | 25 H7 | 70 H7 | 105 |
500 | 0.3 | 150.6 | 25 H7 | 110 H7 | 147 |
512 | 0.3 | 154.2 | 25 H7 | 110 H7 | 151 |
Custom target wheels
Upon customer request Lenord + Bauer will manufacture
your target wheels to your specific requirements. Please
send us a design drawing of your target wheel (if possible as
a dxf file) to[email protected].
Assembly
With this method the target wheel is not manufactured to exactly fit the shaft, instead the inside diameter is made slightly smaller. The target wheel cannot be fitted to the shaft at normal temperatures. By heating the target wheel the material expands and can be pushed onto the shaft. As the target wheel cools it shrinks and is pressed firmly onto the shaft.
Bolting to shaft shoulder
The target wheel is pushed onto the shaft and fastened to the shaft shoulder using screws.
The target wheel is pushed onto the shaft and pressed against this component using a shaft nut. Upon request the target wheel can also be equipped with an integrated shaft nut, for this purpose a corresponding thread is cut on the inside diameter.
Prevention of movement in relation to the shaftFor special applications feather keyways on the inside diameter of the target wheel provide protection against twisting.