Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
  • B25F—COMBINATION OR MULTI-PURPOSE TOOLS NOT OTHERWISE PROVIDED FOR; DETAILS OR COMPONENTS OF PORTABLE POWER-DRIVEN TOOLS NOT PARTICULARLY RELATED TO THE OPERATIONS PERFORMED AND NOT OTHERWISE PROVIDED FOR
  • B25F5/00—Details or components of portable power-driven tools not particularly related to the operations performed and not otherwise provided for
  • B25F5/001—Gearings, speed selectors, clutches or the like specially adapted for rotary tools
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
  • F16C35/00—Rigid support of bearing units; Housings, e.g. caps, covers
  • F16C35/04—Rigid support of bearing units; Housings, e.g. caps, covers in the case of ball or roller bearings
  • F16C35/06—Mounting or dismounting of ball or roller bearings; Fixing them onto shaft or in housing
  • F16C35/063—Fixing them on the shaft
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
  • F16C35/00—Rigid support of bearing units; Housings, e.g. caps, covers
  • F16C35/04—Rigid support of bearing units; Housings, e.g. caps, covers in the case of ball or roller bearings
  • F16C35/06—Mounting or dismounting of ball or roller bearings; Fixing them onto shaft or in housing
  • F16C35/067—Fixing them in a housing
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16H—GEARING
  • F16H57/00—General details of gearing
  • F16H57/02—Gearboxes; Mounting gearing therein
  • F16H57/021—Shaft support structures, e.g. partition walls, bearing eyes, casing walls or covers with bearings
  • F16H57/022—Adjustment of gear shafts or bearings
  • F16H2057/0221—Axial adjustment
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16H—GEARING
  • F16H55/00—Elements with teeth or friction surfaces for conveying motion; Worms, pulleys or sheaves for gearing mechanisms
  • F16H55/02—Toothed members; Worms
  • F16H55/17—Toothed wheels
  • F16H55/18—Special devices for taking up backlash
  • F16H55/20—Special devices for taking up backlash for bevel gears
• • 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
  • Y10T74/1966—Intersecting axes
  • Y10T74/19665—Bevel gear type
• • 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
  • Y10T74/19688—Bevel

Definitions

• the invention relates to a power tool which comprises a housing, an output shaft connected a rotation motor to via an angle drive, wherein the angle drive comprises a drive spindle with a pinion, and a bevel gear connected to the output shaft, and a thrust bearing axially supporting the drive spindle relative to the housing.
• the play between the gears is crucial .
• This play depends mainly on the axial position of the pinion and, hence, the drive spindle.
• the acceptable tolerance for the axial position of the pinion relative to the bevel gear is no more than +/- 0.01 mm.
• a common way of adjusting the pinion position is to use shims, but that technique is cumbersome and not accurate enough.
• the multiple contact surfaces between the shims, the drive spindle bearing and the housing also add to a slightly resilient support of the bearing and an accuracy of +/- 0.01 mm of the drive spindle and pinion position is not at all guaranteed.
• the shims technique is rather time consuming and not suitable in mass production.
• the main object of the invention is to provide a power tool with an angle drive wherein an accurate enough setting of the pinion to bevel gear play is easily and safely accomplished.
• Fig. 1 shows a longitudinal section through the forward end of a power tool including the angle drive according to a first embodiment of the invention
• Fig. 2 shows, on a larger scale, a fraction II of Fig. 1,
• Fig. 3 shows a side view of a lock element comprised in the power tool illustrated in Figs .1 and 2,
• Fig. 4 shows a front view of the lock element in Fig. 3
• Fig. 5 illustrates the pinion bearing arrangement according to a second embodiment of the invention
• Fig. 6 shows a lock element for securing the setting of the pinion the embodiment illustrated in Fig. 5.
• a section through a power tool which comprises a housing 10 supporting an output shaft 11 driven by a rotation motor (not shown) , and an angle drive 12 connecting the motor to the output shaft 11.
• the angle drive 12 comprises a drive spindle 15 coupled to the motor and being formed integrally as a one-piece member with a pinion 16, and a bevel gear 17 formed integrally with the output shaft 11.
• the output shaft 11 At its forward end the output shaft 11 is journalled in a ball bearing 18, whereas the rear end of the output shaft 11 comprises an extension 20 which is supported in the housing 10 by a needle bearing 21.
• the drive spindle 15 is rotatively journalled in the housing 10 via a needle bearing 22 for transferring radial forces and a ball bearing 24 for transferring axial forces to the housing 10.
• a needle bearing 22 for transferring radial forces
• a ball bearing 24 for transferring axial forces to the housing 10.
• both the drive spindle 15 and the output shaft 11 are exposed to axial forces which are transferred to the housing 10 via the bearings 18 and 24.
• the bearing 24 comprises an angular contact bearing of the type having a full number of balls 25 without any separating ball cage.
• the bearing 24 comprises an outer ring 26 secured between a shoulder 27 in the housing 10 and a ring screw 28 co-operating with a threaded portion 29 in the housing 10.
• the bearing 24 also includes an inner ring 31 which at its forward end is formed with a internal thread 32 for co-operation with a threaded portion 33 on the drive spindle 15. At its rear end, the inner ring 31 is formed with a number of axially directed teeth 34 for cooperation with an annular lock element 35.
• the lock element 35 is formed with inwardly directed teeth 36 for co-operation with axially directed splines 37 on the drive spindle 15, and has axially directed teeth 39 for engagement with the teeth 34 on the inner ring 31.
• the lock element 35 is also provided with a circumferential groove 40 for supporting an O-ring seal 41.
• a lock ring 42 supported in a peripheral groove 43 on the drive spindle 15.
• the output shaft 11 and the bearing 18 are first put in place. Then, the thrust bearing 24 is assembled and mounted on the drive spindle 15 with the inner ring 31 threaded onto the drive spindle portion 33 as far as possible. Thereafter, the drive spindle 15 together with the bearing 24 is introduced into the housing 10 until the outer ring 26 of the bearing 24 rests against the shoulder 27 in the housing 10. The outer ring 26 is secured to the housing 10 by mounting and tightening of the ring screw 28. In this position the pinion 16 engages the bevel gear 17, but there is a substantial play between the gear teeth.
• the axial play between the pinion 16 and the bevel gear 17 is to be set to obtain a correct engagement between the gear teeth of the pinion 16 and bevel gear 17. This is accomplished by rotating the inner ring 31 of the thrust bearing 24 such that the inner ring 31 moves backwards pressing the balls 25 against the outer ring 26. This results in a forward movement of the drive spindle 15, and when the drive spindle 15 has come to a position where the play between the pinion 16 and the bevel gear 17 is nill and there is experienced a certain resistance against rotation the inner ring 31. Then, the inner ring 31 is rotated backwards a certain predetermined angle for obtaining the correct desired play in the angle drive.
• the lock element 35 is shoved along the drive spindle splines 37 until the axially directed teeth 39 engage the teeth 34 of the inner ring 31. Then, the lock ring 42 is mounted in the groove 43 in the drive spindle 15. Now, the inner ring 31 is rotationally locked, and the set play between the pinion 16 and bevel gear 17 is safely maintained.
• the inner ring of the bearing 124 is divided into two halves 131 a, b one of which 131a is supported against a shoulder 127 on the drive spindle 115.
• the other inner ring half 131 b is axially locked by a lock ring 128.
• the outer ring 126 of the bearing 124 has a rear extension with an external thread 132 arranged for co-operation with a threaded portion 133 of the housing 110.
• the outer ring 126 is formed with two grooves (not illustrated) on which is mounted a lock element 135 in the form of a sheet steel washer with two inwardly directed teeth 136 for co-operation with the non-illustrated grooves on the outer ring 126.
• the outer ring 126 is safely locked against further rotation in that a rear flange 142 on the lock element 135 is deformed into engagement with axially directed teeth 134 at the end of a forward section of the housing 110. Thereby, the outer ring 126 is maintained in its correct position.
• Assembling the thrust bearing according to this embodiment of the invention is similar to the process described above, namely put together the bearing 124 separately with the drive spindle 115 and introducing this assembly into the housing 110, thereby threading the outer ring 126 into the threaded portion 133 of the housing 110 until there is experienced a torque resistance when rotating the angle drive. Then, the outer ring 126 is rotated a predetermined angle in a reverse direction, thereby pulling the bearing 124 and the drive spindle 115 a distance corresponding to the desired gear teeth play between the pinion 116 and the bevel gear 117. Then, the lock element 135 is deformed to engage the teeth 134 on the housing 110, so as to secure the obtained angular position of the outer ring 126 and the set play between the gear teeth of the angle drive.
• both the above described bearing arrangements are based on the inventive idea that either one of the ball bearing rings of the thrust bearing is axially adjustable, whereas the other one of the bearing rings is rigidly secured to the housing or the drive spindle, alternatively. This means an accurate and simple setting of the axial play between the pinion and the bevel gear of the angle drive.

Landscapes

• Engineering & Computer Science (AREA)
• General Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Gear Transmission (AREA)
• Mounting Of Bearings Or Others (AREA)

Priority Applications (3)

Applications Claiming Priority (2)

Publications (1)

Family

ID=29398648

Family Applications (1)

Country Status (5)

Cited By (10)

Families Citing this family (18)

Citations (3)

Family Cites Families (18)

• 2003
  • 2003-10-03 SE SE0302623A patent/SE526996C2/sv not_active IP Right Cessation
• 2004
  • 2004-10-04 WO PCT/SE2004/001406 patent/WO2005032769A1/en not_active Ceased
  • 2004-10-04 EP EP04775500A patent/EP1667820B1/en not_active Expired - Lifetime
  • 2004-10-04 US US10/574,534 patent/US7963346B2/en active Active
  • 2004-10-04 JP JP2006532229A patent/JP4982181B2/ja not_active Expired - Lifetime

Patent Citations (3)

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