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EP-4240136-B1 - SYSTEMS AND METHODS FOR TOOL-FREE GARDEN MACHINE DETACHABLE IMPLEMENT CHANGE

EP4240136B1EP 4240136 B1EP4240136 B1EP 4240136B1EP-4240136-B1

Inventors

  • LUO, Heng

Dates

Publication Date
20260513
Application Date
20201109

Claims (15)

  1. A garden machine (100) comprising a system for removably coupling a detachable implement (120) to the garden machine (100), the system comprising: a motor shaft locking apparatus (131) configured to engage a motor shaft assembly of the garden machine (100) and discourage movement of a shaft (111) of the motor shaft assembly, wherein the motor shaft locking apparatus (131) comprises one or more lockers (211) for engaging a first portion of the shaft assembly of the garden machine (100) discouraging shaft rotation when the motor shaft locking apparatus (131) engages the motor shaft assembly, and wherein the first portion of the shaft assembly is configured in correspondence with the one or more shaft locking apparatus for the discouraging shaft rotation, wherein a locker (211) of the one or more lockers (211) is in communication with a safety interlock to prevent operation of the motor when the motor shaft locking apparatus (131) is engaged; and wherein the one or more lockers (211) comprise a sliding locker (211) having a wide slot section (212) configured for unimpeded rotation of the shaft when the motor shaft locking apparatus (131) is disengaged and a narrow slot section (213) configured for discouraging rotation of the shaft when the motor shaft locking apparatus (131) is engaged; and an implement securing apparatus (132) configured for lockedly affixing the detachable implement (120) to the shaft (111) of the motor shaft assembly through manual manipulation and for removal through manual manipulation when the motor shaft locking apparatus (131) is engaged.
  2. The garden machine of claim 1, wherein the implement securing apparatus (132) and the motor shaft locking apparatus (131) cooperate to facilitate installation and removal of the detachable implement (120) from the shaft (111) without aid of tools other than the implement securing apparatus (132) and the motor shaft locking apparatus (131).
  3. The garden machine of claim 1, wherein the motor shaft locking apparatus (131) further comprises: a biased actuator (214) configured to encourage relative movement of the sliding locker (211) to interface with the first portion of the shaft assembly when the shaft (111) is insufficiently aligned with the narrow slot section (213); or an energy storage apparatus (217) biasing the sliding locker (211) to a position in which the first portion of the shaft assembly is disposed in the wide slot section (212); or both the biased actuator (214) and the energy storage apparatus (217).
  4. The garden machine of claim 1, wherein the implement securing apparatus (132) comprises: one or more manually operated releases controlling interfacing of the implement securing apparatus (132) with the shaft (111), wherein a second portion of the shaft (111) is configured in correspondence with the one or more manually operated releases for the controlling interfacing of the implement securing apparatus (132); and wherein the one or more manually operated releases optionally comprise a pawl (531) having a bias applied thereto encouraging the pawl (531) to engage the second portion of the shaft and discourage movement of the implement securing apparatus (132) during operation of the garden machine (100).
  5. The garden machine of claim 1, wherein the garden machine (100) comprises a lawn mower and the detachable implement (120) comprises a grass cutting blade.
  6. The garden machine of claim 1, wherein the detachable implement (120) is a detachable grass cutting blade and wherein the garden machine (100) is a lawn mower, the system comprising: the motor shaft locking apparatus (131) being manually actuated; and the implement securing apparatus (132) configured interface with a second portion of the shaft (111), wherein the implement securing apparatus (132) includes one or more manually operated releases controlling rotation of the implement securing apparatus (132) relative to the shaft (111), wherein the implement securing apparatus (132) and the motor shaft locking apparatus (131) cooperate to facilitate installation and removal of the detachable grass cutting blade from the shaft (111) without aid of tools other than the implement securing apparatus (132) and the motor shaft locking apparatus (131), and wherein the second portion of the shaft (111) is configured in correspondence with the one or more manually operated releases for the controlling interfacing of the implement securing apparatus (132); and wherein the one or more manually operated releases optionally comprise a pawl (531) having a bias applied thereto encouraging the pawl (531) to engage the second portion of the shaft and discourage movement of the implement securing apparatus (132) during operation of the garden machine (100).
  7. The garden machine of claim 6, wherein the motor shaft locking apparatus (131) further comprises: an energy storage apparatus (217) biasing the sliding locker (211) to a position in which the first portion of the shaft assembly is disposed in the wide slot section (212); or a biased actuator (214) configured to encourage relative movement of the sliding locker (211) to interface with the first portion of the shaft assembly when the shaft is insufficiently aligned with the narrow slot section (213); or both the biased actuator (214) and the energy storage apparatus (217).
  8. The garden machine of claim 1, wherein the motor shaft locking apparatus (131) comprises a pull wire (215) and the sliding locker (211) is engageable by applying tension to the pull wire (215).
  9. A method for removably coupling a detachable implement (120) to the garden machine (100) of any of claims 1 to 8, the method comprising: engaging the motor shaft locking apparatus (131) through slidably moving a locker (211) of the one or more lockers (211) to discourage movement of the shaft (111) of the motor shaft assembly; disengaging a manually operated release of the implement securing apparatus (132) affixing the detachable implement (120) to the shaft (111) of the motor shaft assembly through manual manipulation; and twisting the implement securing apparatus (132) relative to the shaft (111) while the release is disengaged and the shaft (111) is discouraged from movement, wherein the implement securing apparatus (132) and the motor shaft locking apparatus (131) cooperate to facilitate removal of the detachable implement (120) from the shaft (111) without aid of tools other than the implement securing apparatus (132) and the motor shaft locking apparatus (131).
  10. The method of claim 9, wherein: the locker (211) engages a first portion of the shaft assembly of the garden machine (100) when the motor shaft locking apparatus (131) is engaged; the first portion of the shaft assembly is configured in correspondence with the locker (211) for the discouraging shaft rotation; and the locker (211) optionally comprises a wide slot section (212) configured for unimpeded rotation of the shaft (111) when the motor shaft locking apparatus (131) is disengaged and a narrow slot section (213) configured for discouraging rotation of shaft (111) when the motor shaft locking apparatus (131) is engaged.
  11. The method of claim 10, further comprising: applying a bias force encouraging relative movement of the locker to interface with the first portion of the shaft assembly when the shaft (111) is insufficiently aligned with the narrow slot (213) section.
  12. The method of claim 10, further comprising: overcoming a bias force encouraging the locker (211) to a position in which the first portion of the shaft assembly is disposed in the wide slot section (212) when engaging the motor shaft locking apparatus (131).
  13. The method of claim 10, wherein: a second portion of the shaft (111) is configured in correspondence with the one or more manually operated release for controlling interfacing of the implement securing apparatus (132); and the disengaging the manually operated release optionally comprises overcoming a bias force applied to a pawl (531) of the manually operated release to pivot an end of the pawl (531) away from the second portion of the shaft (111).
  14. The method of claim 9, wherein the garden machine (100) comprises a lawn mower and the detachable implement (120) comprises a grass cutting blade.
  15. The method of claim 9, wherein engaging the motor shaft locking apparatus (131) through slidably moving a locker (211) of the one or more lockers (211) to discourage movement of the shaft (111) of the motor shaft assembly comprises applying tension to the pull wire (215).

Description

TECHNICAL FIELD The present invention relates generally to garden machines having detachable implements and, more particularly, to techniques facilitating installation and/or removal of detachable implements with respect to a host garden machine without aid of separate tools. BACKGROUND OF THE INVENTION Various configurations of garden machines are commonly used in performing routine tasks in daily life. For example, garden machines such as lawn mowers, string trimmers, grass edgers, chainsaws, etc. are used every day by persons performing work and leisure related tasks. These garden machines often comprise a motor of some form (e.g., electric motor or internal combustion motor) outputting power via a shaft which drives an implement configured for the related task. As examples, a lawn mower may drive an implement in the form of a grass cutting blade, a string trimmer may drive an implement in the form of string spool head, a grass edger may drive an implement in the form of an edging blade, and a chainsaw may drive an implement in the form of a bar and chain. An implement may be configured to be detachable from a host garden machine. For example, detachable implements may be utilized to accommodate selection of an implement configuration for a particular task (e.g., selectively installing a grass cutting blade configured for mulching or clipping collection, etc.) and/or to facilitate replacing or repairing a damaged implement (e.g., removal and reinstalling a grass cutting blade after sharpening its previously dulled edges or replacing a dull grass cutting blade with a sharp grass cutting blade, etc.). Typically, one or more tools are required for changing (e.g., removing and/or installing) a detachable implement. For example, a hand tool in the form of a wrench (e.g., open-end wrench, socket wrench, or adjustable wrench) in the appropriate size for engaging a fastener affixing the implement to a shaft assembly of the garden machine is needed for changing a detachable implement. Additionally, a hand tool in the form of a brace or second wrench is often needed to prevent movement of the shaft and implement when tightening or loosening the fastener affixing the implement to a shaft assembly of the machine for changing the detachable implement. Garden machines having detachable implements are often operated in areas away from repair facilities or places in which it is convenient or customary to store tools appropriate to changing detachable implements. For example, a lawn mower may be operated in a home environment in which the owner has a very limited selection of tools, and thus appropriately sized hand tools for changing a detachable implement may not be available to the operator. In another example, a lawn mower may be operated in a field or other large parcel of land relatively far from a supply of tools and, although a replacement grass cutting blade may be carried by the operator, sufficient tools for changing the grass cutting blade may not be available. In a similar example, a chainsaw may be operated in forest relatively far from a supply of tools and, although a replacement bar and/or chain may be carried by the operator, sufficient tools for changing a damaged bar and chain may not be available. Accordingly, it is often inconvenient and sometimes even impossible to change a detachable implement despite the implement having been configured for detachment and reattachment. CN 105 612 905 A describes a lawn-trimmer and brush-cutter mechanism in which a springloaded stop post on the motor cover engages a Y-shaped groove on the rotor to hold it stationary. This rotor lock aims to facilitate the tool-free removal or attachment of the cutting head. US 2005/155227 A1 describes a spring-biased, elongated locking member that slides through recesses in the motor housing and gearbox casting; when the external end is pressed, its half-hex locking portion engages a hexagonal bushing press-fit on the armature shaft to stop rotation. Releasing the pressure lets the spring return the member to its unlocked position, allowing tool-free shaft locking for blade changes. BRIEF SUMMARY OF THE INVENTION The present invention is directed to systems and methods which provide for tool-free detachable implement change. In accordance with embodiments of the present invention, changing (e.g., installation and/or removal) of detachable implements with respect to a host garden machine is facilitated through the use of a tool-free implement change mechanism without aid of separate tools. Tool-free implement change mechanisms of embodiments may, for example, be provided for use in changing various implements, such as grass cutting blades, string spool heads, leaf blowers, cultivators, hedge trimmer blades, brush cutters, edging blades, bars and chains, etc., attached/attachable to the motor assemblies of corresponding garden machines (e.g., lawn mowers, string trimmers, grass edgers, chainsaws, etc.). A tool-free implement change