Drill unit with a motor unit and a gear unit

Patent metadata

Field	Value
Publication number	US-11858052-B2
Application number	US-202217670581-A
Country	US
Kind code	B2
Filing date	Feb 14, 2022
Priority date	Feb 15, 2021
Publication date	Jan 2, 2024
Grant date	Jan 2, 2024

Abstract

The present disclosure relates to a drill tool ( 1 ), such as a core drill tool ( 1 ), comprising a motor unit ( 2 ) and a gear unit ( 3 ). The motor unit ( 2 ) comprises an electric motor ( 4 ) and a motor drive shaft ( 5 ) that extends along a first longitudinal axis ( 6 ) from the electric motor ( 4 ) and protrudes out of a motor unit housing ( 7 ) via a motor exit aperture ( 8 ) in a housing end part ( 9 ) and comprises a drive shaft gear ( 10 ). The drive shaft gear ( 10 ) is adapted to propel a drill shaft ( 14 ) that extends along a second longitudinal axis ( 15 ) and comprises a tool holder ( 16 ) that is adapted to hold a tool. The housing end part ( 9 ) comprises a wall part ( 17 ) arranged transversally to the longitudinal axes ( 6, 15 ) and is adapted to close the gear unit cavity ( 11 ) and to separate the electric motor ( 4 ) from the gear unit cavity ( 11 ).

First claim

The invention claimed is:

1. A drill tool comprising a motor unit and a gear unit, wherein the motor unit comprises an electric motor and a motor drive shaft that extends along a first longitudinal axis from the electric motor and protrudes out of a motor unit housing via a motor exit aperture in a housing end part and comprises a drive shaft gear, and wherein the gear unit comprises a gear unit housing with a gear unit cavity that in turn comprises at least one cavity gear, wherein the drive shaft gear is adapted to mate with a cavity gear that at least indirectly is adapted to propel a drill shaft that extends along a second longitudinal axis and comprises a tool holder that is adapted to hold a tool, wherein the housing end part comprises a wall part arranged transversally to the first and second longitudinal axes and is adapted to close the gear unit cavity and to separate the electric motor from the gear unit cavity,
wherein the motor unit housing comprises the wall part that separates the gear unit cavity and the electric motor, and
wherein the gear unit housing is open toward the wall part.

2. The drill tool according to claim 1 , wherein the gear unit housing and the motor unit housing together are comprised in a drill tool main housing.

3. The drill tool according to claim 1 , wherein the motor unit housing or the gear unit housing comprises a circumferentially running slot that is adapted to receive a sealing gasket that is adapted to function as a seal between the gear unit housing and the motor unit housing.

4. The drill tool according to claim 1 , wherein the housing end part comprises a circumferentially running sealing flange that extends from the wall part towards and into the gear unit cavity parallel to the first and second longitudinal axes, such that the sealing flange and the gear unit cavity overlap in a direction perpendicular to the first and second longitudinal axes.

5. The drill tool according to claim 4 , wherein the sealing flange and the gear unit housing have corresponding surfaces that are parallel to, and circumvent, the first and second longitudinal axes, and wherein the surfaces have complementary shapes where they abut each other.

6. The drill tool according to claim 5 , wherein the surfaces follow non-cylindrical shapes around the first and second longitudinal axes.

7. The drill tool according to claim 4 , wherein the sealing flange comprises a circumferentially running slot that is adapted to receive a sealing gasket that is adapted to function as a seal between the gear unit housing and the motor unit housing.

8. The drill tool according to claim 1 , wherein the housing end part comprises a circumferentially running first supporting flange that extends from the wall part towards and into the gear unit cavity parallel with the first longitudinal axis, wherein the first supporting flange comprises the motor exit aperture and holds a bearing arrangement for the motor drive shaft, the motor drive shaft extending through the first supporting flange.

9. The drill tool according to claim 8 , wherein the housing end part comprises at least one circumferentially running further supporting flange that extends from the wall part towards and into the gear unit cavity along an axis parallel with the first longitudinal axis, wherein each further supporting flange holds a corresponding bearing arrangement adapted to receive and support a corresponding gear shaft that is attached to a corresponding gear in the gear unit.

10. The drill tool according to claim 1 , wherein the motor unit housing is attached to the gear unit housing with fastening means.

11. The drill tool according to claim 10 , wherein the fastening means engage the gear unit housing and the motor unit housing at a position radially outward of a sealing flange.

12. The drill tool according to claim 1 , wherein the gear unit cavity accommodates a lubricating oil or grease, and the wall part of the motor unit housing together with the gear unit cavity is arranged to encapsulate said liquid.

13. The drill tool according to claim 12 , wherein the drill tool comprises a fan for guiding cooling air towards the motor unit, wherein the cooling air is arranged to be guided to at least one side of the motor unit housing, said at least one side being different from a side of the motor unit comprising the wall part, such that the motor unit is directly cooled by a liquid on one external side and by cooling air on at least one other external side.

14. The drill tool according to claim 13 , wherein the cooling fan is driven by the electric motor and located on a side of the motor unit opposite the side of the motor unit engaging the gear unit cavity.

15. The drill tool according to claim 1 , wherein the electric motor is powered by a battery.

16. The drill tool according to claim 1 , wherein the at least one cavity gear comprises an incoming gear adapted to mate with the drive shaft gear, and an outgoing gear operably coupled to the incoming gear by means of at least one intermediate gear, wherein the outgoing gear is attached to the drill shaft.

Assignees

• Husqvarna Ab

Inventors

• Vidlund Robert
• Carlsson Pär
• Liljenfeldt Peter
• Grennhag David

Classifications

• B23B45/008 Primary

  Gear boxes, clutches, bearings, feeding mechanisms or like equipment · CPC title

• B25B23/141

  Mechanical overload release couplings · CPC title

• F16H35/10

  Arrangements or devices for absorbing overload or preventing damage by overload · CPC title

• B23B2260/044

  Clutches · CPC title

• B23B2260/122

  Safety devices · CPC title