US20020023796A1 - Transmisson for a steerable drive wheel of a forklift - Google Patents

Transmisson for a steerable drive wheel of a forklift Download PDF

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Publication number
US20020023796A1
US20020023796A1 US09/318,859 US31885999A US2002023796A1 US 20020023796 A1 US20020023796 A1 US 20020023796A1 US 31885999 A US31885999 A US 31885999A US 2002023796 A1 US2002023796 A1 US 2002023796A1
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Prior art keywords
pinion
hypoid
transmission
wheel
spur gear
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US09/318,859
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US6349781B1 (en
Inventor
Rainer Kruse
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ZF Friedrichshafen AG
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ZF Friedrichshafen AG
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60K—ARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES; ARRANGEMENT OR MOUNTING OF PLURAL DIVERSE PRIME-MOVERS IN VEHICLES; AUXILIARY DRIVES FOR VEHICLES; INSTRUMENTATION OR DASHBOARDS FOR VEHICLES; ARRANGEMENTS IN CONNECTION WITH COOLING, AIR INTAKE, GAS EXHAUST OR FUEL SUPPLY OF PROPULSION UNITS IN VEHICLES
    • B60K7/00—Disposition of motor in, or adjacent to, traction wheel
    • B60K7/0007—Disposition of motor in, or adjacent to, traction wheel the motor being electric
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60K—ARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES; ARRANGEMENT OR MOUNTING OF PLURAL DIVERSE PRIME-MOVERS IN VEHICLES; AUXILIARY DRIVES FOR VEHICLES; INSTRUMENTATION OR DASHBOARDS FOR VEHICLES; ARRANGEMENTS IN CONNECTION WITH COOLING, AIR INTAKE, GAS EXHAUST OR FUEL SUPPLY OF PROPULSION UNITS IN VEHICLES
    • B60K17/00—Arrangement or mounting of transmissions in vehicles
    • B60K17/04—Arrangement or mounting of transmissions in vehicles characterised by arrangement, location, or kind of gearing
    • B60K17/043—Transmission unit disposed in on near the vehicle wheel, or between the differential gear unit and the wheel
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60K—ARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES; ARRANGEMENT OR MOUNTING OF PLURAL DIVERSE PRIME-MOVERS IN VEHICLES; AUXILIARY DRIVES FOR VEHICLES; INSTRUMENTATION OR DASHBOARDS FOR VEHICLES; ARRANGEMENTS IN CONNECTION WITH COOLING, AIR INTAKE, GAS EXHAUST OR FUEL SUPPLY OF PROPULSION UNITS IN VEHICLES
    • B60K17/00—Arrangement or mounting of transmissions in vehicles
    • B60K17/30—Arrangement or mounting of transmissions in vehicles the ultimate propulsive elements, e.g. ground wheels, being steerable
    • B60K17/303—Arrangement or mounting of transmissions in vehicles the ultimate propulsive elements, e.g. ground wheels, being steerable with a gearwheel on the steering knuckle or kingpin axis
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B66—HOISTING; LIFTING; HAULING
    • B66F—HOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
    • B66F9/00—Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes
    • B66F9/06—Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes movable, with their loads, on wheels or the like, e.g. fork-lift trucks
    • B66F9/075—Constructional features or details
    • B66F9/07572—Propulsion arrangements
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60K—ARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES; ARRANGEMENT OR MOUNTING OF PLURAL DIVERSE PRIME-MOVERS IN VEHICLES; AUXILIARY DRIVES FOR VEHICLES; INSTRUMENTATION OR DASHBOARDS FOR VEHICLES; ARRANGEMENTS IN CONNECTION WITH COOLING, AIR INTAKE, GAS EXHAUST OR FUEL SUPPLY OF PROPULSION UNITS IN VEHICLES
    • B60K7/00—Disposition of motor in, or adjacent to, traction wheel
    • B60K2007/0046—Disposition of motor in, or adjacent to, traction wheel the motor moving together with the vehicle body, i.e. moving independently from the wheel axle
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60K—ARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES; ARRANGEMENT OR MOUNTING OF PLURAL DIVERSE PRIME-MOVERS IN VEHICLES; AUXILIARY DRIVES FOR VEHICLES; INSTRUMENTATION OR DASHBOARDS FOR VEHICLES; ARRANGEMENTS IN CONNECTION WITH COOLING, AIR INTAKE, GAS EXHAUST OR FUEL SUPPLY OF PROPULSION UNITS IN VEHICLES
    • B60K7/00—Disposition of motor in, or adjacent to, traction wheel
    • B60K2007/0069—Disposition of motor in, or adjacent to, traction wheel the motor axle being perpendicular to the wheel axle
    • B60K2007/0084—Disposition of motor in, or adjacent to, traction wheel the motor axle being perpendicular to the wheel axle the motor axle being vertical
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L2220/00—Electrical machine types; Structures or applications thereof
    • B60L2220/40—Electrical machine applications
    • B60L2220/46—Wheel motors, i.e. motor connected to only one wheel
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T74/00—Machine element or mechanism
    • Y10T74/19—Gearing
    • Y10T74/19642—Directly cooperating gears
    • Y10T74/19679—Spur
    • Y10T74/19684—Motor and gearing
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T74/00—Machine element or mechanism
    • Y10T74/21—Elements
    • Y10T74/2186—Gear casings

Definitions

  • the invention concerns a transmission for a steerable drive wheel of a forklift according to the preamble of the main claim.
  • Such transmissions have been disclosed in DE 31 33 027 or DE 44 24 305.
  • the transmissions are pivotable around a vertical axle via a rocking bearing.
  • the transmissions have a spur gear stage and a second reduction stage.
  • the pinion of the spur gear stage can be driven by a slip-on electric motor and drives a spur gear sitting upon a pinion shaft.
  • the pinion teeth of the second reduction stage are located, as a rule, directly upon the vertical pinion shaft.
  • the vertical pinion shaft is supported in the transmission housing by means of roller bearings.
  • the roller bearing in the area of the pinion of the second reduction stage being designated as pinion gearing.
  • the bevel gear of the second reduction stage is non-rotatably connected with the drive wheel by a horizontal output shaft.
  • the required high reduction ratio of the second reduction stage causes very strong reaction forces on the pinion bearing when the forklift is accelerated or decelerated.
  • the maximum load capacity of the pinion bearing and of the toothing is reached as the load stresses increase.
  • the outer dimensions are limited by the enveloping circle when the transmission is pivoted and by the housing in the area of the bevel gear.
  • the housing must project below, not above, the rim of the drive wheel in order that damage to the transmission can be eliminated in case of defective tires of the drive wheel.
  • the problem to be solved by the invention is to provide a transmission with a capacity for high load stresses While being limited by preset limits of the outer dimensions and a preset reduction ratio. Particularly, the invention must obtain a higher load capacity at the pinion bearing and at the pinion teeth.
  • the problem is solved by the fact that the second reduction stage is designed as a hypoid wheel set with positive axle offset.
  • the pinion axle does not cut the bevel gear axle. It is offset around the so-called crossing step or hypoid offset.
  • the diameter of the hypoid pinion (with equal bevel gear diameter and equal ratio) becomes larger than in corresponding bevel gear transmissions.
  • the larger pinion diameter makes possible a thicker piriion shaft and therewith a larger design of the pinion bearing.
  • This larger design of the pinion bearing cannot be used in the transmissions known due to the smaller pinion diameter.
  • the positive offset produces a larger helix angle of the pinion, which determines a larger length per tooth that takes part in the meshing and a larger overlap ratio. This has an advantageous effect upon the load capacity.
  • the maximum thickness of the pinion shaft is obtained when the diameter of the pinion shaft is equal to the root diameter of the hypoid pinion in the transition between the toothing region and the cylindrical part of the pinion shaft.
  • FIG. 1 shows a sectional illustration of the transmission according to the invention
  • FIG. 2 shows in sideview the hypoid wheel set of the transmission according to the invention
  • FIG. 3 shows a topview
  • the transmission shown in FIG. 1 for a forklift creates the operative connection between the electric motor 2 , shown only in part, and the drive wheel 4 .
  • the transmission including the drive wheel 4
  • the transmission is suspended pivotally around the vertical motor shaft axle 8 by means of a rocking bearing 6 .
  • the devices needed for pivoting are known and are not shown, since they are in no way related to the invention.
  • the inner ring 10 of the rocking bearing 6 is integrated in an upper housing part 12 which together with the lower housing part 14 forms the transmission housing.
  • the housing parts are interconnected on the joint 16 by bolts 18 and centering pins 20 .
  • On the motor shaft 22 is fastened the pinion 24 of a spur gear stage.
  • the pinion 24 meshes with a spur gear 26 which is fastened on the free upper end of a vertical pinion shaft 28 , 30 belonging to the hypoid wheel set.
  • the toothed region of the hypoid pinion 30 is located on the free lower end of the pinion shaft 28 .
  • the pinion shaft is supported in the lower housing part 14 by two roller bearings, an upper roller bearing 32 and a lower roller bearing designated as pinion bearing 34 .
  • the bevel gear 36 of the hypoid wheel set is non-rotatably connected by interlocking teeth 37 with a horizontal output shaft 40 .
  • the output shaft 40 is supported in the lower housing part 14 by means of two roller bearings 42 , 44 and is connected with the rim 46 of the output wheel 4 which supports the tire 48 .
  • the pinion bearing 34 undergoes considerable stresses, especially in the radial direction.
  • the pinion bearing 34 abuts axially directly on the toothed region of the hypoid pinion 30 in order to keep as short as possible the distance of the lines of action of the toothing force and of the bearing force. This step minimizes the bearing force of the pinion bearing 34 .
  • this arrangement also limits the maximum diameter of the pinion shaft 28 or of the inner ring of the bearing 34 .
  • the pinion shaft 28 should not have, in the area of the bearing seat, any recesses produced by the cutting of teeth.
  • the diameter of the pinion shaft 28 and therewith the size of the pinion bearing 34 are larger and have more supporting capacity. This is made possible by the fact that the second reduction step is designed as a hypoid wheel set with positive axle offset.
  • FIG. 2 shows a sideview of the hypoid wheel set consisting of hypoid pinion 30 and bevel wheel 36 .
  • the positive axle offset 38 causes the helix angle of the helical or spiral cut pinion around the contact angle to be larger than the helix angle of the bevel wheel.
  • the diameter of the pinion (with equal bevel wheel diameter and equal ratio) becomes larger than in the corresponding bevel-gear drive.
  • the pressure upon the tooth flanks, and therewith the inclination to pitting, turns out to be less.
  • the larger helix angle of the pinion produces a larger transverse module and thus a larger diameter with equal number of teeth. Thereby is made possible a larger diameter of the pinion shaft 28 and of the bearing inner ring of the pinion bearing 34 .
  • the larger design of the pinion bearing 34 allows for a greater load capacity.
  • the transmission according to the invention with the second reduction stage designed as a hypoid wheel set altogether satisfies higher load requirements wherein preset limits of the outer dimensions and a preset reduction ratio must be adhered to. Also clearly seen in FIG. 2, a larger angle ⁇ produces more flank length per tooth taking part in the meshing and a greater overlap ratio.
  • Advantageous values for the axle offset 38 are in the range of the seventh to thirteenth part of the bevel wheel diameter with helix angles of the hypoid pinion of 44° and of the bevel wheel of 31°.
  • FIG. 3 In the topview of FIG. 3 is diagrammatically shown the flange surface of the lower housing part 14 .
  • the spur wheel stage consisting of pinion 24 and spur gear 26 is shown only in outline.
  • the axle offset 38 in travel direction can be clearly seen.
  • the axle offset was produced by the pinion shaft 28 being moved together with the hypoid pinion 30 and the spur gear 26 (FIG. 1) along an orbit 50 around the motor shaft axle 8 or pivot axle.
  • the axle offset was produced by the pinion shaft 28 being moved together with the hypoid pinion 30 and the spur gear 26 (FIG. 1) along an orbit 50 around the motor shaft axle 8 or pivot axle.
  • the axle offset was produced by the pinion shaft 28 being moved together with the hypoid pinion 30 and the spur gear 26 (FIG. 1) along an orbit 50 around the motor shaft axle 8 or pivot axle.

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  • Engineering & Computer Science (AREA)
  • Transportation (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • Structural Engineering (AREA)
  • Civil Engineering (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Geology (AREA)
  • Gear Transmission (AREA)
  • General Details Of Gearings (AREA)
  • Forklifts And Lifting Vehicles (AREA)
  • Arrangement And Mounting Of Devices That Control Transmission Of Motive Force (AREA)
  • Power Steering Mechanism (AREA)

Abstract

In a transmission for a steerable drive wheel (4) of a forklift, which transmission is pivotable around a vertical axle (8) and contains a spur gear stage (24, 26) and a second reduction stage formed by a pinion shaft (28, 30) and a bevel wheel (36), the second reduction stage is designed as hypoid wheel set (30, 36) with positive axle offset. Unlike the designs known already, it is hereby possible, by adhering to preset limits of the outer dimensions and a preset reduction ratio, to obtain a toothing of more supporting capacity and a thicker pinion shaft (28) so that the loads of the tooth flanks are canceled and it is possible to use a design of a high loaded pinion bearing (34) having more supporting capacity.

Description

    BACKGROUND OF THE INVENTION
  • The invention concerns a transmission for a steerable drive wheel of a forklift according to the preamble of the main claim. Such transmissions have been disclosed in DE 31 33 027 or DE 44 24 305. In the forklift the transmissions are pivotable around a vertical axle via a rocking bearing. The transmissions have a spur gear stage and a second reduction stage. The pinion of the spur gear stage can be driven by a slip-on electric motor and drives a spur gear sitting upon a pinion shaft. The pinion teeth of the second reduction stage are located, as a rule, directly upon the vertical pinion shaft. The vertical pinion shaft is supported in the transmission housing by means of roller bearings. The roller bearing in the area of the pinion of the second reduction stage being designated as pinion gearing. The bevel gear of the second reduction stage is non-rotatably connected with the drive wheel by a horizontal output shaft. [0001]
  • The required high reduction ratio of the second reduction stage causes very strong reaction forces on the pinion bearing when the forklift is accelerated or decelerated. The maximum load capacity of the pinion bearing and of the toothing is reached as the load stresses increase. For certain applications, it is not possible to enlarge the dimensions of the transmission, due to a lack of installation space. The outer dimensions are limited by the enveloping circle when the transmission is pivoted and by the housing in the area of the bevel gear. The housing must project below, not above, the rim of the drive wheel in order that damage to the transmission can be eliminated in case of defective tires of the drive wheel. [0002]
    • SUMMARY OF THE INVENTION
  • Departing from the already known transmission, the problem to be solved by the invention is to provide a transmission with a capacity for high load stresses While being limited by preset limits of the outer dimensions and a preset reduction ratio. Particularly, the invention must obtain a higher load capacity at the pinion bearing and at the pinion teeth. The problem is solved by the fact that the second reduction stage is designed as a hypoid wheel set with positive axle offset. [0003]
  • In such a known hypoid wheel set described, for example, in Niemann's “Maschinenelements” Vol. 3, 1983, the pinion axle does not cut the bevel gear axle. It is offset around the so-called crossing step or hypoid offset. In positive offset, the diameter of the hypoid pinion (with equal bevel gear diameter and equal ratio) becomes larger than in corresponding bevel gear transmissions. The larger pinion diameter makes possible a thicker piriion shaft and therewith a larger design of the pinion bearing. This larger design of the pinion bearing cannot be used in the transmissions known due to the smaller pinion diameter. The positive offset produces a larger helix angle of the pinion, which determines a larger length per tooth that takes part in the meshing and a larger overlap ratio. This has an advantageous effect upon the load capacity. [0004]
  • When the pinion bearing abuts directly axially on the teeth of the hypoid pinion, an advantage is obtained by minimizing the bearing stresses. [0005]
  • The maximum thickness of the pinion shaft is obtained when the diameter of the pinion shaft is equal to the root diameter of the hypoid pinion in the transition between the toothing region and the cylindrical part of the pinion shaft. [0006]
  • A specially silent operation of the transmission and a high load capacity are obtained when the gears of the hypoid wheel set are spiral cut.[0007]
    • BRIEF DESCRIPTION OF THE DRAWING(S)
  • The invention is explained in detail herebelow with reference to the enclosed drawings in which [0008]
  • FIG. 1 shows a sectional illustration of the transmission according to the invention; [0009]
  • FIG. 2 shows in sideview the hypoid wheel set of the transmission according to the invention; [0010]
  • FIG. 3 shows a topview.[0011]
    • DESCRIPTION OF THE PREFERRED EMBODIMENT(S)
  • The transmission shown in FIG. 1 for a forklift creates the operative connection between the [0012] electric motor 2, shown only in part, and the drive wheel 4. In the forklift the transmission, including the drive wheel 4, is suspended pivotally around the vertical motor shaft axle 8 by means of a rocking bearing 6. The devices needed for pivoting are known and are not shown, since they are in no way related to the invention. The inner ring 10 of the rocking bearing 6 is integrated in an upper housing part 12 which together with the lower housing part 14 forms the transmission housing. The housing parts are interconnected on the joint 16 by bolts 18 and centering pins 20. On the motor shaft 22 is fastened the pinion 24 of a spur gear stage. The pinion 24 meshes with a spur gear 26 which is fastened on the free upper end of a vertical pinion shaft 28, 30 belonging to the hypoid wheel set. The toothed region of the hypoid pinion 30 is located on the free lower end of the pinion shaft 28. The pinion shaft is supported in the lower housing part 14 by two roller bearings, an upper roller bearing 32 and a lower roller bearing designated as pinion bearing 34. The bevel gear 36 of the hypoid wheel set is non-rotatably connected by interlocking teeth 37 with a horizontal output shaft 40. The output shaft 40 is supported in the lower housing part 14 by means of two roller bearings 42, 44 and is connected with the rim 46 of the output wheel 4 which supports the tire 48.
  • Upon accelerations or decelerations of the forklift, the pinion bearing [0013] 34 undergoes considerable stresses, especially in the radial direction. The pinion bearing 34 abuts axially directly on the toothed region of the hypoid pinion 30 in order to keep as short as possible the distance of the lines of action of the toothing force and of the bearing force. This step minimizes the bearing force of the pinion bearing 34. But this arrangement also limits the maximum diameter of the pinion shaft 28 or of the inner ring of the bearing 34. For reasons of processing and durability, the pinion shaft 28 should not have, in the area of the bearing seat, any recesses produced by the cutting of teeth.
  • Compared to known transmissions having the same outer dimensions and the same reduction ratios, the diameter of the [0014] pinion shaft 28 and therewith the size of the pinion bearing 34 are larger and have more supporting capacity. This is made possible by the fact that the second reduction step is designed as a hypoid wheel set with positive axle offset.
  • FIG. 2 shows a sideview of the hypoid wheel set consisting of [0015] hypoid pinion 30 and bevel wheel 36. The positive axle offset 38 causes the helix angle of the helical or spiral cut pinion around the contact angle to be larger than the helix angle of the bevel wheel. Thereby the diameter of the pinion (with equal bevel wheel diameter and equal ratio) becomes larger than in the corresponding bevel-gear drive. The pressure upon the tooth flanks, and therewith the inclination to pitting, turns out to be less. The larger helix angle of the pinion produces a larger transverse module and thus a larger diameter with equal number of teeth. Thereby is made possible a larger diameter of the pinion shaft 28 and of the bearing inner ring of the pinion bearing 34. The larger design of the pinion bearing 34 allows for a greater load capacity.
  • Another advantage of the thicker pinion shaft results from the greater rigidity and the accompanying lower flexure of the pinion shaft under load whereby an even support of the toothing is obtained. [0016]
  • The transmission according to the invention with the second reduction stage designed as a hypoid wheel set altogether satisfies higher load requirements wherein preset limits of the outer dimensions and a preset reduction ratio must be adhered to. Also clearly seen in FIG. 2, a larger angle ∝ produces more flank length per tooth taking part in the meshing and a greater overlap ratio. Advantageous values for the [0017] axle offset 38 are in the range of the seventh to thirteenth part of the bevel wheel diameter with helix angles of the hypoid pinion of 44° and of the bevel wheel of 31°.
  • In the topview of FIG. 3 is diagrammatically shown the flange surface of the [0018] lower housing part 14. The spur wheel stage consisting of pinion 24 and spur gear 26 is shown only in outline. The axle offset 38 in travel direction can be clearly seen. Based on a design of the transmission without hypoid wheel set, the axle offset was produced by the pinion shaft 28 being moved together with the hypoid pinion 30 and the spur gear 26 (FIG. 1) along an orbit 50 around the motor shaft axle 8 or pivot axle. Hereby could be prevented an enlargement of the enveloping circle in the critical range of the spur gear 26 and a change of the center of distance 52 or of the reduction ratio between pinion 24 and spur gear 26.
    • REFERENCE NUMERALS
  • [0019]
     2 electric motor 30 hypoid pinion
     4 drive wheel 32 roller bearing
     6 rocking bearing 34 pinion bearing
     8 motor shaft axle (= swivel axis) 36 bevel wheel
    10 inner ring 37 interlocking teeth
    12 upper housing part 38 axle offset
    14 lower housing part 40 output shaft
    16 joint 42 roller bearing
    18 bolt 44 roller bearing
    20 centering pin 46 rim
    22 motor shaft 48 tire
    24 pinion 50 orbit
    26 spur gear 52 center distance
    28 pinion shaft

Claims (3)

1. A transmission for a steerable drive wheel of a forklift having a transmission housing (12, 14), pivotable around a vertical axle (8) and lodgeable in the vehicle chassis, upon which an electric motor (2) can be superposed coaxially with the rocking axle (8), a spur gear stage consisting of a pinion (24) and a spur gear (26) and a second reduction stage consisting of a pinion shaft (28, 30) and a bevel wheel (36) wherein said pinion (24) of said spur gear stage can be non-rotatably connected with the output shaft (22) of said electric motor (2), said spur gear (26) is non-rotatably connected with the vertical pinion shaft (28) of said second reduction stage and said bevel wheel (36) of said second reduction stage can be non-rotatably connected by a horizontal output shaft (40) with the drive wheel (4), and wherein said second reduction stage is designed as hypoid wheel set (30, 36) with positive axle offset (38).
2. The transmission according to claim 1, wherein the pinion bearing (34) abuts axially directly on the teeth of the hypoid pinion (30).
3. The transmission according to claim 1, wherein the gears (30, 36) of said hypoid wheel set are spiral cut.
US09/318,859 1998-06-12 1999-05-26 Transmission for a steerable drive wheel of a forklift Expired - Lifetime US6349781B1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE19826067 1998-06-12
DE19826067A DE19826067B4 (en) 1998-06-12 1998-06-12 Transmission for a steerable drive wheel of a material handling vehicle
DE19826067.9 1998-06-12

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US6349781B1 US6349781B1 (en) 2002-02-26
US20020023796A1 true US20020023796A1 (en) 2002-02-28

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DE (1) DE19826067B4 (en)
IT (1) IT1312213B1 (en)

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CN104325877A (en) * 2014-09-28 2015-02-04 中国船舶工业系统工程研究院 Electric wheel structure directly driven by motor

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* Cited by examiner, † Cited by third party
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DE10130100A1 (en) 2001-06-21 2003-01-16 Zahnradfabrik Friedrichshafen Gearbox for a steerable drive wheel
DE10132318A1 (en) * 2001-07-06 2003-01-23 Kordel Antriebstechnik Gmbh Single-wheel driving mechanism for floor conveyor vehicle, has driven running wheel directly connected with bevel gear which is rotatably supported by stationary pivot of gear housing
DE10252192A1 (en) * 2002-11-09 2004-05-27 Zf Friedrichshafen Ag Axle transmission unit for rail car, comprising bevel gear located in particularly low position for compact size
DE10330032A1 (en) * 2003-07-03 2005-01-20 Zf Friedrichshafen Ag bevel gear
BRPI0406454A (en) 2003-11-12 2005-12-20 Mattel Inc Spiral propelled vehicle
EP1541402B1 (en) * 2003-12-11 2008-04-02 Kanzaki Kokyukoki Mfg. Co., Ltd. Hydraulic transaxle and vehicle comprising it
FR2875439B1 (en) * 2004-09-21 2007-03-02 Conception & Dev Michelin Sa GROUND CONNECTION FOR A VEHICLE COMPRISING A WHEEL AND AN INTEGRATED SUSPENSION WITH A WHEEL
DE102005017723A1 (en) * 2005-04-15 2006-10-26 Zf Friedrichshafen Ag Drive unit for an industrial truck
CN100371200C (en) * 2005-09-27 2008-02-27 马燕翔 Automobile steering roller drive mechanism
DE102005055567A1 (en) * 2005-11-22 2007-06-21 Zf Friedrichshafen Ag Drive for an industrial truck
DE102005058400A1 (en) * 2005-11-30 2007-05-31 Jungheinrich Ag Driving and steering system for wheel of industrial truck, has electronic control unit, which consists of printed circuit board, arranged coaxially between traction motor and steering motor or steering motor and steering gear
US20070289791A1 (en) * 2006-06-17 2007-12-20 Manfred Kaufmann Sideloader with improved visual operability
US20070289798A1 (en) * 2006-06-17 2007-12-20 Manfred Kaufmann Sideloader forklift with all wheel steering
US20110024219A1 (en) * 2007-05-10 2011-02-03 Aarhus Universitet Omni rotational driving and steering wheel
DE112009001482T5 (en) 2008-07-09 2011-04-21 McLaren Performance Technologies, Inc., SOUTHFIELD Axially compact storage for a wheel within a transmission
EP2199137B1 (en) * 2008-12-18 2012-06-20 Klingelnberg AG Lateral wheel motor assembly
DE102010028929A1 (en) 2010-05-12 2011-11-17 Zf Friedrichshafen Ag Steerable drive assembly for industrial lorry, has angle gear box including intermediate gear, which is connected with driving wheel of vertically aligned drive shaft and output wheel of horizontally aligned driven shaft
DE102010040756A1 (en) 2010-09-14 2012-03-15 Zf Friedrichshafen Ag Wheel drive unit for use in material handling equipment e.g. electrical propelled forklift, to transport goods in horizontal position, has vertically extending housing comprising displacement bodies that project into lubricant
DE102010062291A1 (en) * 2010-12-01 2012-06-06 Zf Friedrichshafen Ag Drive arrangement for industrial vehicle, comprises drive motor and gear housing with shifted gear for driving drive wheel, where gear wheel of shifted gear is rotationally connected on wheel shaft of drive wheel
JP2012210899A (en) * 2011-03-31 2012-11-01 Aisin Seiki Co Ltd In-wheel motor device
ES2493924T3 (en) * 2011-09-29 2014-09-12 Siemens Aktiengesellschaft Industrial gearbox
DE102011087326A1 (en) 2011-11-29 2013-05-29 Zf Friedrichshafen Ag Drive unit for industrial truck, has gearbox having gear stage, where gear stage consists of pinion and output wheel, and pinion and output wheel are connected with each other in toothing engagement
DE102011121795B4 (en) * 2011-12-21 2013-09-19 Kordel Antriebstechnik Gmbh Drive unit for a steerable impeller
DE102013200388A1 (en) * 2013-01-14 2014-07-17 Zf Friedrichshafen Ag Drive for a truck with steering assistance
DE102013225708A1 (en) * 2013-12-12 2015-06-18 Zf Friedrichshafen Ag Drive for an industrial truck
DE102014225139A1 (en) * 2014-12-08 2016-06-09 Zf Friedrichshafen Ag Drive unit for an industrial truck and industrial truck
DE102015222965A1 (en) 2015-11-20 2017-05-24 Zf Friedrichshafen Ag Drive unit and wheel drive with drive unit
DE102016216425A1 (en) 2016-08-31 2018-03-01 Zf Friedrichshafen Ag Drive arrangement for an industrial truck
US20190168620A1 (en) * 2017-12-01 2019-06-06 Divergent Technologies, Inc. Integrated wheel assemblies using motor and speed reducer
DE102018216856A1 (en) * 2018-10-01 2020-04-02 Zf Friedrichshafen Ag Gearbox for a steerable drive wheel of an industrial truck
DE102018221210A1 (en) 2018-12-07 2020-06-10 Zf Friedrichshafen Ag Gearbox for a steerable drive wheel of an industrial truck
US11655891B2 (en) 2020-09-09 2023-05-23 Mahindra N.A. Tech Center Method of machining an axle carrier housing
US11535057B2 (en) 2020-09-09 2022-12-27 Mahindra N.A. Tech Center Axle assembly with sealed wheel end bearings and sealed pinion input bearings
US11225107B1 (en) 2020-09-09 2022-01-18 Mahindra N.A. Tech Center Axle carrier housing with reinforcement structure
US11648745B2 (en) 2020-09-09 2023-05-16 Mahindra N.A. Tech Center Modular tooling for axle housing and manufacturing process

Family Cites Families (25)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3213700A (en) * 1963-05-06 1965-10-26 Rockwell Standard Co Gear drives
US3534825A (en) * 1968-08-05 1970-10-20 Eaton Yale & Towne Vehicle drive and steer mechanism
US3765259A (en) * 1971-02-25 1973-10-16 600 Machine Tools Ltd Forward and reverse drive mechanism for a machine tool
GB1414135A (en) * 1971-11-24 1975-11-19 Cragg H Wheel chairs
US3812736A (en) * 1972-08-30 1974-05-28 Gen Electric Reversing mechanism
DE2616310C3 (en) * 1976-04-12 1986-08-21 Siemens AG, 1000 Berlin und 8000 München Drive for an electric rail vehicle
AU7256081A (en) 1980-07-21 1982-01-28 Imi Enots Ltd. Quick acting releasable tube coupling
US4372176A (en) * 1980-09-22 1983-02-08 Terry Clegia L Tapered tooth helical gear drive train for eliminating the need for end thrust bearings
US4391157A (en) * 1980-10-17 1983-07-05 Deere & Company Bevel gear and pinion drive with biased thrust bearing
DE3133027C2 (en) * 1981-08-20 1986-10-16 Carl Hurth Maschinen- und Zahnradfabrik GmbH & Co, 8000 München Gear for a steerable drive wheel of a fluorine transport vehicle
DE8124384U1 (en) * 1981-08-20 1986-04-10 Carl Hurth Maschinen- und Zahnradfabrik GmbH & Co, 8000 München Gear for a steerable drive wheel of an industrial truck
US4518287A (en) * 1982-07-07 1985-05-21 Western Gear Corporation Method of face mill generation of spiral bevel gears with integral central structure and resulting product
US4513839A (en) * 1983-05-06 1985-04-30 Yale Materials Handling Corporation Disc brake arrangement for steering and traction unit
FR2550139B1 (en) * 1983-08-02 1985-11-29 Glaenzer Spicer Sa IMPROVED DOUBLE JOINT TRANSMISSION DEVICE, PARTICULARLY FOR VEHICLE
US4612816A (en) * 1983-10-28 1986-09-23 Lazar Chalik Gear assembly
GB2155416B (en) * 1984-01-21 1988-03-09 Kubota Ltd Vehicle front wheel drive
RU2025615C1 (en) * 1991-12-18 1994-12-30 Евгений Анисимович Кирсанов Reduction gear
JP2866247B2 (en) * 1992-02-25 1999-03-08 住友重機械工業株式会社 Series and series of orthogonal gear units with motor
DE4230429C2 (en) * 1992-09-11 1997-10-16 Roland Man Druckmasch Bevel gear for a printing machine
IT1266360B1 (en) * 1993-05-20 1996-12-27 Bonfiglioli Riduttori Spa MULTI-STAGE ANGULAR REDUCER.
US5558174A (en) * 1994-01-26 1996-09-24 Schaeff, Incorporated Drive train assembly
DE4413759A1 (en) * 1994-04-21 1995-10-26 Otto Michael Militzer Drive for personnel transportation systems, esp. travolators
DE4424305C2 (en) * 1994-07-09 2000-01-05 Zf Hurth Gotha Gmbh Drive unit for an industrial truck consisting of electric motor and gearbox
JP3661888B2 (en) * 1995-10-31 2005-06-22 アイシン精機株式会社 Method for wrapping bevel gears with toothed teeth
IT1285601B1 (en) * 1996-03-08 1998-06-18 Bonfiglioli Riduttori Spa MULTI-STAGE ANGULAR REDUCER

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104325877A (en) * 2014-09-28 2015-02-04 中国船舶工业系统工程研究院 Electric wheel structure directly driven by motor

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DE19826067A1 (en) 1999-12-16
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US6349781B1 (en) 2002-02-26
ITMI990860A1 (en) 2000-10-23

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