1. Geared to a higher standard™

2. Rack & Pinion Drives
• ZTRS – Small pinion with bearing support
• ZTR – Small pinion without additional bearing support
• ZR – Traditional style flange mounted pinion
• Rack
• Lubrication
• Mounting

3. ZTRS Part Numbering

4. Support Housing Position

5. ZTRS Rack & Pinion Drives
4 Case Sizes Available:
PH(A)7 – PH(A)(Q)10
Pinion System:
Helical & Straight Tooth
Module 2 – 10
Quality 5 (DIN, AGMA 12)
Feed Force:
Up to 124kN / 27,875lbs helical tooth
Up to 121kN / 27,200lbs straight tooth
Feed Speed:
Up to 4.7 m/s
Linear Backlash:
Standard ZTRS-PH ≤ 21 – 72 µm
Reduced ZTRS-PHA ≤ 7 – 24 µm

6. ZTRS – PH Rack & Pinion Drives
High Force Helical / Straight Tooth System
Integrated lubrication by felt
Know-how and competence pinion (optional) ready to
from two drive specialists connect to the central lubrication
or to a grease cup
Gear unit and gear rack Optimal adaption to the mass
perfectly matched to each moment of inertia by varying the
other, optimal utilization of the gear ratios / number of pinion
gear unit due to support teeth
bearing cover.
Also available as right-angle
Torque reduction more gear unit PHK / PHKX
than 50%
Directly attached STÖBER
Linear backlash reduction servo motors possible
more than 50%
Concentricity of the pinion
Linear stiffness can be ≈ 25µm (optional ≤ 10µm)
increased up to ten times
Information for selection, assembling Removable pinion
Smaller gear unit ratio and lubrication of rack and pinion If necessary, the pinion can be
1 stage instead of 2 stages drives changed.

7. ZTR Part Numbering

8. ZTR Rack & Pinion Drives
6 Case Sizes Available:
PH(A)4 – PH(A)10
Pinion System:
Helical & Straight Tooth
Module 2 – 8
Quality 5 (DIN, AGMA 12)
Feed Force:
Up to 57kN / 12,800lbs helical tooth
Up to 45.5kN / 10,225lbs straight tooth
Feed Speed:
Up to 4.7 m/s
Linear Backlash:
Standard ZTR-PH ≤ 12 – 50 µm
Reduced ZTR-PHA ≤ 4 – 17 µm

9. ZTR– PH Rack & Pinion Drives
Helical / Straight Tooth System
Know-how and competence from Optimal adaption to the mass
two drive specialists moment of inertia by varying the
gear ratios / number of pinion
Gear unit and gear rack perfectly teeth
matched to each other
Also available as right-angle
Torque reduction more gear unit PHK / PHKX
than 50%
Directly attached STÖBER
Linear backlash reduction servo motors possible
more than 50%
Linear stiffness can be Concentricity of the pinion
increased by up to five times ≈ 25µm (optional ≤ 10µm)
Smaller gear unit ratio
1 stage instead of 2 stages
Removable pinion
If it´s necessary, a new pinion is
Information for selection, assembling attachable
and lubrication of rack and pinion
drives

10. ZR Part Numbering

11. ZR Rack & Pinion Drives
6 Case Sizes Available:
PH(A)4 – PH(A)7
Pinion System:
Helical Only
Module 2 – 4
Quality 5 (DIN, AGMA 12)
Feed Force:
Up to 12.3kN / 2765lbs helical tooth
Feed Speed:
Up to 6.8 m/s
Linear Backlash:
Standard ZR-PH ≤ 31 – 57 µm
Reduced ZR-PHA ≤ 10 – 19 µm

12. ZR– PH Rack & Pinion Drives
Helical Tooth System
Know-how and Optimal adaption to the mass
competence from two drive moment of inertia by varying the
specialists gear ratios / number of pinion
teeth
Gear unit and gear rack
perfectly matched to each
other Also available as right-angle
gear unit PHK / PHKX
To bridge large distances
between gear unit and rack Directly attached STÖBER
servo motors possible
Small distance between
Concentricity of the pinion
point of force and bearings
≈ 25µm
of the gearbox.
optional ≤ 10µm
 high bearing service life
 low deflection
Cost-efficient alternative
Suitable for high-speed Removable pinion
applications, because of the large If necessary, a new pinion is
pinion diameter attachable
Information for selection, assembling
and lubrication of rack and pinion
drives

13. Rack & Pinion Drawings on the Web

14. Gear Rack
Sizes Available:
Module 2-10
Lengths Available:
0.5, 1.0, 2.0 meters
Quality:
AGMA 8 – 12
DIN 4 -10
Helical & Straight
Precision Levels:
Basic = Soft
Precision = Quenched & Tempered
High-Precision = Induction-Hardened
Ultra-Precision = Hardened & Ground

15. Gear Rack Precision
Rack Quality Minimum
Rack Pitch Deviation GTf Typical
Level Backlash *
(Positioning Accuracy) Applications
(Lowest to Highest) (Repeatability)
Light Loads &
Soft ~0.06 mm < 0.150 mm per meter
Medium Accuracy
(DIN 9, ~AGMA 9) (0.0024”) (0.0018”/ft)
(Plasma, low loads)
Medium Loads &
Quenched & Tempered ~0.04 mm < 0.100 mm per meter
Medium Accuracy
(DIN 8, ~AGMA 10) (0.0016”) (0.0012”/ft)
(plasma)
Hardened & Ground ~0.03 mm < 0.060 mm per meter Heavy to Medium
(DIN 7/8, ~AGMA 10/11) (0.0012”) (0.0008”/ft) Material handeling, woord
working, linear axis)
Hardened & Ground < 0.048 mm per meter
(DIN 6, ~AGMA 12) Heavy Loads & High Accuracy
(0.0006”/ft)
(Machine Tool, Multiple Pinion
Hardened & Ground Contact, lifting axis, water jet)
~0.02 mm < 0.030 mm per meter
(DIN 5)
29 series
(0.0008”) (0.0004”/ft)
Hardened & Precision < 0.012 mm per meter Heavy Loads &
Ground (DIN 4) Very High Accuracy
48 series
(0.0001”/ft) (High precision machine tool)

16. Rack Part Number
28.20.100
Series Number Module & Holes Length
25 – Soft First Digit – Module 1.0 to 10.0 025 – ¼ meter
27, 34 – Induction-Hardened Second Digit - Mounting Holes 050 – ½ meter
28 – Hardened & Ground 100/105 – 1.0 meter
29 – Helical Hardened & Ground 150/155 – 1.5 meter
33 – Quenched & Tempered 200/205 – 2.0 meter
35, 37 – Round Rack
36 – Stainless Steel Rack
38 – Helical Quenched & Tempered
39 – Helical Induction-Hardened
46 – Hardened & Ground DIN 4
47 – Helical Soft
48 – Helical Hardened & Ground DIN 4
49 – Integrated Rack

17. Mounting
Tolerances/Instructions

18. Geared to a higher standard™

19. Advantages of Removeable
Pinions
• The bolt connection of the pinion to the output shaft
of the gearbox allows for changing the pinion.
• Reasons for a pinion change:
– Strong contamination leading to increased wear
– Strong wear as a result of lubrication failure or lack of
manual lubrication
– Crash
– Other defects or failures

20. Disadvantages of Welded
Pinions
• Change of pinion is impossible
• Risks of welding:
– Crack formation
– Thermal deformations
– Notching effect leading to the risk of break down
– Welding spots in the gear teeth

21. Reduction of Torque – ZTRS /
ZTR

22. Reduced Linear Backlash >
50%Higher Precision – ZTRS / ZTR

23. Increase of Linear Stiffness >
10X

24. Increase of Linear Stiffness –
ZTRS
Gearbox Gearbox
C=250Nm/arcmin C=250Nm/arcmin
d=100mm
d=50mm
F=10.000N F=10.000N
• Torque T=Fxr 500Nm 250Nm
• Tors. Defl. φ=M/C 2arcmin 1arcmin
• Lin. Defl. s = d/2 x tan φ 29,1µm 7,3µm
• Lin. Stiffn. CL = F / s 344N/µm 1370N/µm
• Increase 400%

25. Increase of Linear Stiffness –
ZTRS ZR ZTRS
Fv
FB
Fv
fZTRS
fZR
FS
FA FB
Gearbox
C=250Nm/arcmin
Gearbox
C=250Nm/arcmin FA At the same feed force the bending in the
d=100mm
tooth engagement is approximately half!
d=50mm
F=10.000N F=10.000N

26. Upgraded Load Capacity
 By using the support bearing the bending is
halved!
 Width crowning optimized for the bending
 Significantly improved contact pattern
 Reduced contact pressure at the tooth flank
 Increased safety, respectively higher lifetime,
especially with dirty or insuffient lubrication

27. Summary
Gearbox Gearbox
C = const. C = const.
• Pinion diameter factor 1 1.6 – 2.3
• Linear Stiffness factor – only dia. effect 1 2.6 – 5.3
• Linear Stiffness factor – only bend. effect 1 2
• Total Linear Stiffness Factor 1 5.2 – 10.6

28. Ratio Reduction – ZTRS / ZTR

29. Bearing Load – ZR vs ZTRS
ZR ZTRS
Fv
FB
Fv
FS
FA FB
The load at the A-
FA By using the same feed force,
bearing is limiting
the feed force the bearings are loaded only 25%!

30. Bearing Load – ZR vs ZTRS
ZR ZTRS
Fv
FB
Fv
FS
The feed force can be increased FA FB
FA until the maximum torque of the
gearbox or rack and pinion is
reached!

31. Felt Pinion to Lubricate – ZTRS
Felt pinion
Location of
lubrication port.

32. Lubrication
LUBRICATION IS CRITICAL TO MAINTAIN QUALITY AND
LIFE
– Felt Lubrication Gear:
Available with RH for helical pinions
LH for helical racks
Also straight for straight tooth rack & pinions
– Lubricator:
125CC dispensers
475cc

33. Catalog Values
The performance data of rack and pinion drives is listed in the STÖBER catalog called Rack
and Pinion Drives.
The data in the catalog is prepared to be very user-friendly.
All values are converted on the linear axis.
M2B  Fv2B max. permissable acceleration feed force
M2N  Fv2N rated feed force
M2NOT  Fv2NOT emergency-off feed force
∆φ2  ∆s linear backlash without meshing of the teeth at the rack and pinion
C2  CLges total linear spring rigidity including the assembled pinion
Kv  Speed constant – speed [m/s] of the linear axis per 1000 RPM of the motor
KM1  Torque constant – needed torque at the input per 1000 N feed force
without dynamic effects – mass inertia
For general information as well as for calculation with ServoSoft, some additional gear data is
indicated.
m  module
Z  number of teeth
dw  pitch circle diameter

34. Catalog Values
The calculated specified performance data takes into account all concerned
load-bearing components.
Rated feed force – Fv2N – depends on the lowest value of the gearbox rated
torque and/or the force in case of a bearing lifetime Lh=20.000h at
n1=500 1/min.
Max. permissable acceleration feed force – Fv2B – depends on the lowest value
of the max. permissable acceleration torque of the gearbox (M2B) and/or the static
load carrying capacity of the bearings in connection with a 3 safety factor
(2 with ball bearings), 1.25 flange bolting safety factor, and torque of the
rack and pinion teeth.
Emergency-off feed force – Fv2NOT – depends on the lowest value of the
emergency-off torque of the gearbox (M2NOT) and the flange bolting and
2 safety factor of the rack and pinion teeth.

35. ZTRS / ZTR / ZR Input Options
MT/
MT
MT/ME/MF

36. Example DMS
Stober Alpha
PH521F0100MT SP140-MF2-28
40mm Mod 2 helical pinion 75mm Mod 3 helical pinion
10:1 ratio (single stage) 28:1 ratio (single stage)
3 arcmin (55Nm/arcmin) 5 arcmin (53Nm/arcmin)
0.5m/s velosity ////1.0m/s2 acc/dec 0.5m/s velosity ////1.0m/s2 acc/dec
5500 lb load 5500 lb load
DETAILS
0.017mm linear backlash (317% >) 0.054mm linear backlash
1.3 arcmin of torsional deflection (196%>) 2.54 arcmin of torsional deflection
7.5µm of linear deflection (369%>) 27.7µm of linear deflection
477.3N/µm of linear stiffness (367%>) 129.9N/µm of linear stiffness
$4024.00 GB & Pinion $490.00/meter $4356.00 GB & Pinion ($590.00/meter)