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
ZTRS – PH Rack & Pinion Drives High Force Helical / Straight Tooth System Integrated lubrication by feltKnow-how and competence pinion (optional) ready tofrom two drive specialists connect to the central lubrication or to a grease cupGear unit and gear rack Optimal adaption to the massperfectly matched to each moment of inertia by varying theother, optimal utilization of the gear ratios / number of piniongear unit due to support teethbearing cover. Also available as right-angleTorque reduction more gear unit PHK / PHKXthan 50% Directly attached STÖBERLinear backlash reduction servo motors possiblemore than 50% Concentricity of the pinionLinear stiffness can be ≈ 25µm (optional ≤ 10µm)increased up to ten times Information for selection, assembling Removable pinionSmaller gear unit ratio and lubrication of rack and pinion If necessary, the pinion can be1 stage instead of 2 stages drives changed.
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
ZTR– PH Rack & Pinion Drives Helical / Straight Tooth SystemKnow-how and competence from Optimal adaption to the masstwo drive specialists moment of inertia by varying the gear ratios / number of pinionGear unit and gear rack perfectly teethmatched to each other Also available as right-angleTorque reduction more gear unit PHK / PHKXthan 50% Directly attached STÖBERLinear backlash reduction servo motors possiblemore than 50%Linear stiffness can be Concentricity of the pinionincreased by up to five times ≈ 25µm (optional ≤ 10µm)Smaller gear unit ratio1 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
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
ZR– PH Rack & Pinion Drives Helical Tooth SystemKnow-how and Optimal adaption to the masscompetence from two drive moment of inertia by varying thespecialists gear ratios / number of pinion teethGear unit and gear rackperfectly matched to eachother Also available as right-angle gear unit PHK / PHKXTo bridge large distancesbetween gear unit and rack Directly attached STÖBER servo motors possibleSmall distance between Concentricity of the pinionpoint of force and bearings ≈ 25µmof the gearbox. optional ≤ 10µm high bearing service life low deflection Cost-efficient alternativeSuitable for high-speed Removable pinionapplications, because of the large If necessary, a new pinion ispinion diameter attachable Information for selection, assembling and lubrication of rack and pinion drives
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)
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
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
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%
Increase of Linear Stiffness – ZTRS ZR ZTRS Fv FB Fv fZTRS fZR FS FA FB GearboxC=250Nm/arcmin Gearbox C=250Nm/arcmin FA At the same feed force the bending in the d=100mm tooth engagement is approximately half! d=50mmF=10.000N F=10.000N
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
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
Bearing Load – ZR vs ZTRS ZR ZTRS Fv FB Fv FS FA FBThe load at the A- FA By using the same feed force,bearing is limiting the feed force the bearings are loaded only 25%!
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!
Felt Pinion to Lubricate – ZTRS Felt pinion Location of lubrication port.
LubricationLUBRICATION IS CRITICAL TO MAINTAIN QUALITY ANDLIFE– Felt Lubrication Gear: Available with RH for helical pinions LH for helical racks Also straight for straight tooth rack & pinions– Lubricator: 125CC dispensers 475cc
Catalog ValuesThe performance data of rack and pinion drives is listed in the STÖBER catalog called Rackand 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 forceM2N Fv2N rated feed forceM2NOT Fv2NOT emergency-off feed force∆φ2 ∆s linear backlash without meshing of the teeth at the rack and pinionC2 CLges total linear spring rigidity including the assembled pinionKv Speed constant – speed [m/s] of the linear axis per 1000 RPM of the motorKM1 Torque constant – needed torque at the input per 1000 N feed force without dynamic effects – mass inertiaFor general information as well as for calculation with ServoSoft, some additional gear data isindicated.m moduleZ number of teethdw pitch circle diameter
Catalog ValuesThe calculated specified performance data takes into account all concernedload-bearing components.Rated feed force – Fv2N – depends on the lowest value of the gearbox ratedtorque and/or the force in case of a bearing lifetime Lh=20.000h atn1=500 1/min.Max. permissable acceleration feed force – Fv2B – depends on the lowest valueof the max. permissable acceleration torque of the gearbox (M2B) and/or the staticload 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 therack and pinion teeth.Emergency-off feed force – Fv2NOT – depends on the lowest value of theemergency-off torque of the gearbox (M2NOT) and the flange bolting and2 safety factor of the rack and pinion teeth.
Example DMS Stober AlphaPH521F0100MT SP140-MF2-2840mm Mod 2 helical pinion 75mm Mod 3 helical pinion10:1 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/dec5500 lb load 5500 lb load DETAILS0.017mm linear backlash (317% >) 0.054mm linear backlash1.3 arcmin of torsional deflection (196%>) 2.54 arcmin of torsional deflection7.5µm of linear deflection (369%>) 27.7µm of linear deflection477.3N/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)