Patent Application
20240016084
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.
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.
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 mechanism of embodiments of the invention may comprise one or more apparatuses configured to facilitate installation and/or removal of detachable implements with respect to a host garden machine without aid of separate tools. For example, a tool-free implement change mechanism may comprise a motor shaft locking apparatus and/or an implement securing apparatus. An implement securing apparatus of embodiments is configured for affixing detachable implements to a motor shaft assembly of a host garden machine without aid of separate tools. In operation according to embodiments, a motor shaft locking apparatus of embodiments may be engaged to prevent movement of motor shaft (and, correspondingly, the detachable implement) when tightening or loosening an implement securing apparatus used for affixing the detachable implement to the shaft assembly.
In accordance with embodiments of the invention, the apparatuses of a tool-free implement change mechanism are configured for hand-actuation to thereby facilitate their operation without aid of separate tools. For example, an implement securing apparatus of a tool-free implement change mechanism may comprise a hand-actuated implement securing apparatus, such as may comprise one or more manually operated releases for controlling interfacing of the implement securing apparatus with a shaft assembly. The shaft assembly of a host garden machine may be correspondingly configured for controlling interfacing of the implement securing apparatus. A motor shaft locking apparatus of a tool-free implement change mechanism may likewise comprise a hand-actuated motor shaft locking apparatus, such as may comprise one or more manually operable lockers for engaging a portion of the shaft assembly of a host garden machine to discourage shaft rotation. In accordance with some embodiments, a motor shaft locking apparatus of a tool-free implement change mechanism may comprise one or more lockers configured to automatically engage a portion of the shaft assembly of a host garden machine. Irrespective of the motor shaft locking apparatus being configured for manual and/or automatic engagement of a portion of the shaft assembly, the portion of the shaft assembly may be correspondingly configured for engagement by the motor shaft locking apparatus to discourage shaft rotation.
The foregoing has outlined rather broadly the features and technical advantages of the present invention in order that the detailed description of the invention that follows may be better understood. Additional features and advantages of the invention will be described hereinafter which form the subject of the claims of the invention. It should be appreciated by those skilled in the art that the conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims. The novel features which are believed to be characteristic of the invention, both as to its organization and method of operation, together with further objects and advantages will be better understood from the following description when considered in connection with the accompanying figures. It is to be expressly understood, however, that each of the figures is provided for the purpose of illustration and description only and is not intended as a definition of the limits of the present invention.
For a more complete understanding of the present invention, reference is now made to the following descriptions taken in conjunction with the accompanying drawing, in which:
In the example of
A shaft assembly of motor assembly 110 is utilized to drive detachable implement 120 in operation of garden machine 100. Accordingly, in the example of
Tool-free implement change mechanism 130 of embodiments of the invention is shown in the example of garden machine 100 for facilitating changing of detachable implement 120 without aid of separate tools. Tool-free implement change mechanism 130 of the illustrated embodiment includes motor shaft locking apparatus 131 and implement securing apparatus 132 configured to facilitate installation and/or removal of detachable implement 120 with respect to garden machine 100. As described in detail with respect to the examples below, implement securing apparatus 132 of embodiments may be configured for affixing detachable implement 120 to a motor shaft assembly of garden machine 100 without aid of separate tools. Also as described in detail with respect to the examples below, motor shaft locking apparatus 131 of embodiments may be engaged without aid of separate tools to prevent movement of shaft 111 when affixing detachable implement 120 to shaft 111. In accordance with some embodiments, motor shaft locking apparatus 131 may be operable in cooperation with implement securing apparatus 132 to facilitate affixing detachable implement 120 to or removing detachable implement 120 from the motor shaft assembly of garden machine 100 without the use of additional tools. In operation of tool-free implement change mechanism 130, an operator of garden machine 100 may install and/or remove detachable implement 120 by engaging motor shaft locking apparatus 131 (e.g., through manual manipulation or automatic engagement) and loosening or tightening implement securing apparatus 132 through manual manipulation.
Referring first to
Motor shaft locking apparatus 131 of the illustrated embodiment is configured for locking shaft 111 from rotation to facilitate installation and/or removal of detachable implement 120. Accordingly, motor shaft locking apparatus 131 of the example of
In the illustrated example, a second end of shaft 111 extends from the bottom of motor assembly 110, wherein locker 211 of motor shaft locking apparatus 131 is disposed in juxtaposition with a portion of shaft 111 at this second end. It should be appreciated, however, that motor shaft locking apparatus 131 may be disposed in different or alternative locations with respect to shaft 111 according to some embodiments of the invention. For example, motor shaft locking apparatus 131 may be disposed in a position at the top of motor assembly 110, such as to place locker 211 in juxtaposition with a portion of shaft 111 extending between the first end interfaced with detachable implement 120 and a motor housing of motor assembly 110. Moreover, although a single instance of motor shaft locking apparatus 131 (and components thereof) are shown, embodiments of the invention may implement multiple instances of a motor shaft locking apparatus (or components thereof). For example, a first instance of motor shaft locking apparatus 131 may be disposed at the bottom of motor assembly 110 and a second instance of motor shaft locking apparatus 131 (or some components thereof) may be disposed at the top of motor assembly 110.
Locker 211 of motor shaft locking apparatus 131 is configured to interface with a portion of shaft 111 for discouraging rotation of the shaft. In operation according to embodiments, motor shaft locking apparatus 131 is configured to allow free rotation (i.e., unimpeded by motor shaft locking apparatus 131) of shaft 111 when motor shaft locking apparatus 131 is disengaged. However, motor shaft locking apparatus 131 is configured to discourage rotation (e.g., prevent or substantially impede) of shaft 111, and correspondingly detachable implement 120, when engaged for facilitating installing and/or removing detachable implement 120.
Locker 211 of the illustrated embodiment of motor shaft locking apparatus 131 includes wide slot section 212 and narrow slot section 213 configured for selectively allowing and discouraging rotation of shaft 111. In operation according to embodiments of the invention, when shaft 111 is within wide slot section 212, shaft 111 and locker 211 do not interface and shaft 111 is free to rotate. However, when shaft 111 is within narrow slot section 213, shaft 111 and locker 211 interface and shaft 111 is discouraged from rotation. Accordingly, shaft 111 of embodiments may be configured for interfacing with locker 211 for discouraging rotation of the shaft. For example, a portion of shaft 111 disposed in juxtaposition with locker 211 may be provided with a square cross-section configured to cooperate with narrow slot section 213 of locker 211 to discourage rotation of shaft 111 when motor shaft locking apparatus 131 is engaged. Correspondingly, the portion of shaft 111 disposed in juxtaposition with locker 211 is configured to be compatible with wide slot section 212 for allowing free rotation of shaft 111 when motor shaft locking apparatus 131 is disengaged.
It should be appreciated that, although the foregoing example of locker 211 is described with respect to a narrow and wide slot configuration for selectively allowing and discouraging rotation of shaft 111, embodiments of the invention may utilize additional or alternative configurations for lockers of motor shaft locking apparatus 131. For example, locker implementations of embodiments may utilize clamps, grippers, ratchets, open-ended tines, etc. for interfacing with a portion of shaft 111 to selectively discourage rotation. A portion of shaft 111 disposed in juxtaposition with such locker configurations may be provided with one or more features (e.g., grippable or non-slip surface, teeth or ratchet catch, mating surface shape, etc.) configured to cooperate with the locker to discourage rotation of shaft 111 when motor shaft locking apparatus 131 is engaged and compatible with allowing free rotation of shaft 111 when motor shaft locking apparatus 131 is disengaged.
In operation of motor shaft locking apparatus 131 illustrated in
An actuator assembly of motor shaft locking apparatus 131 in the example of
In accordance with some embodiments, motor shaft locking apparatus 131 may be automatically engaged, such as upon powering off of the motor, upon cessation of rotation of shaft 111, etc. Accordingly, motor shaft locking apparatus 131 of embodiments may comprise one or more lockers configured to automatically engage a portion of the shaft assembly of a host garden machine. For example, a servo or other electrically controlled actuator may be coupled to locker 211, such as via pull wire 215 and tension spring 216, to facilitate moving locker 211 relative to shaft 111 for interfacing/de-interfacing with the shaft upon powering off/powering on garden machine 100. As another example, a centrifugal slide mechanism may be implemented with respect to locker 211 facilitate interfacing of locker 211 with shaft 111 after cessation of rotation of the shaft. Such a centrifugal slide mechanism may be implemented in combination with a manual (e.g., using actuator 214 coupled to pull wire 215 and spring 216) or automatic (e.g., servo or other electrically controlled actuator) release to facilitate de-interfacing of locker 211 and shaft 111 upon operation of garden machine 100.
Locker 211 of embodiments is preferably configured to retain a disengaged configuration of motor shaft locking apparatus 131 (e.g., locker 211 remains in a position relative to shaft 111 wherein the shaft remains within wide slot section 212) when actuator 214 is not actuated. For example, motor shaft locking apparatus 131 of the embodiment illustrated in
It should be appreciated that there may be situations in which shaft 111 may be in a position so as to prevent or resist interfacing, or fully interfacing, with motor shaft locking apparatus 131 for discouraging rotation of the shaft. For example, shaft 111 may be radially positioned on occasion such that shaft 111 does not readily fit into the narrow slot section 213 (e.g., shaft 111 may be rotationally oriented such that the sides of the square cross-section are not sufficiently parallel to the inner surfaces of narrow slot section 213 to allow locker 211 to slide relative to the shaft to engage motor shaft locking apparatus 131). Accordingly, locker 211 of embodiments may become “jammed” with shaft 111 disposed at the transition between wide slot section 212 and narrow slot section 213 as force is applied to locker 211 by actuator 214.
The actuator assembly of motor shaft locking apparatus 131 may be configured to accommodate situations in which shaft 111 may not sufficiently align with locker 211 to result in motor shaft locking apparatus 131 becoming engaged. For example, tension spring 216 disposed inline with pull wire 215 of the illustrated embodiment may be configured to accumulate pulling force as actuator 214 is being actuated while locker 211 is “jammed” to nevertheless encourage locker 211 in a direction for narrow slot section 213 interfacing with shaft 111. Upon shaft 111 slightly rotating, the shaft may sufficiently align with locker 211 to allow the accumulated pulling force to encourage interfacing between locker 211 and shaft 111. For example, an operator of garden tool 100 may slightly rotate detachable implement 120, while actuator 214 is being actuated, to cause shaft 111 to come into alignment with locker 211. Additionally or alternatively, the transition between wide slot section 212 and narrow slot section 213 may be configured (e.g., tapered, sloped, etc.) to encourage slight rotation of shaft 111 to come into alignment with locker 211. As shaft 111 comes into alignment with locker 211, force accumulated by tension spring 216 of embodiments encourages relative movement of locker 211 to interface with the shaft and motor shaft locking apparatus 131 becomes engaged.
The locker and actuator assemblies of motor shaft locking apparatus 131 of embodiments of the invention may include features in addition to or in the alternative to the features of the examples above. For example, the actuator assembly may include latching apparatus (e.g., friction fit, latch, lock, catch, clasp, etc.) configured to hold the actuator in an actuated and/or non-actuated position. As another example, a safety interlock (e.g., power disconnect switch, ignition ground switch, etc.) may be provided in communication with the actuator and/or locker to prevent operation of the motor when the motor shaft locking apparatus is engaged.
Referring now to
Implement securing apparatus 132 of the illustrated embodiment includes fastener 311 configured to interface with shaft 111 for affixing detachable implement 120 to the shaft assembly. Fastener 311 may, for example, be integral with or act on implement securing apparatus 132 for facilitating use of implement securing apparatus 132 in affixing detachable implement 120 to the shaft assembly. For example, a portion of the first end of shaft 111 may be configured for interfacing with fastener 311 sufficiently to hold detachable implement 120 and/or transfer power thereto from motor assembly 110 during use of garden tool 100. As shown in
Shaft 111 of embodiments of the invention may be provided with one or more features in addition to the aforementioned fastener interface to facilitate affixing detachable implement 120 to the shaft assembly and/or transfer power to the detachable implement. For example, structures such as a backer plate, torque plate, thrust plate, etc. may be provided with respect to shaft 111 for use in affixing detachable implement 120 to the shaft assembly and/or transferring power to the detachable implement. In the illustrated example, torque plate 430 is configured to provide an additional interface between shaft 111 and detachable implement 120. A portion of the first end of shaft 111 may, for example, be configured for interfacing with torque plate 430 sufficiently to transfer power from motor assembly 110 to detachable implement 120 through torque plate 430 during use of garden tool 100. As shown in
In accordance with some embodiments of the invention, one or more features may be provided to facilitate affixing detachable implement 120 to shaft 111 in a proper orientation. For example, detachable implement 120 may comprise an implement configuration for which a particular face is to face away or toward motor assembly 110, is to be affixed in a particular radial orientation with respect to the shaft, etc. As one example, a grass cutting blade detachable implement 120 may comprise a mulching blade configuration in which airfoil surfaces are provided for creating air circulation within an area below the mower deck for repeated cutting of grass clippings. Proper operation of such a mulching blade configuration may depend upon a particular face of the blade facing the mower deck. One or more structures may be provided to facilitate such desired/proper orientation of detachable implement 120. For example, tangs 432 and 433 may each be provided in different sizes, shapes, locations, etc. to encourage a particular orientation of detachable implement 120 when affixed to shaft 111. As shown in the example of
In accordance with embodiments of the invention, implement securing apparatus 132 is configured for installing or removing detachable implement 120, such as in association with motor shaft locking apparatus 131, without aid of separate tools. Accordingly, implement securing apparatus 132 of embodiments is configured for hand-actuation, such as being shaped to accommodate manipulation by hand and/or utilizing one or more manually operated releases for controlling interfacing of the implement securing apparatus with a shaft assembly. For example, the embodiment of implement securing apparatus 132 illustrated in
In providing for locking implement securing apparatus 132 onto shaft 111, and thus reliably securing detachable implement 120 thereto throughout operation of garden machine 100, one or more manually operated releases for controlling interfacing of the implement securing apparatus with a shaft assembly may be utilized. For example, as shown in
In operation according to embodiments, the engagement between the pawls 531 and toothed portion 412 as a result of the biasing force of springs 532 discourages relative rotation between fastener 311 of implement securing apparatus 132 and shaft 111 in one direction (e.g., avoiding undesired unthreading of fastener 311 and threaded portion 411 during spinning of detachable implement 120). However, when an operator desires to remove implement securing apparatus 132 (e.g., to change detachable implement 120), portions of pawls 531 protruding from implement securing apparatus 132 may be depressed, the biasing force of springs 532 overcome, and the pawls pivoted to disengage from toothed portion 412. As pawls 531 pivot and disengage from toothed portion 412, implement securing apparatus 132 (and correspondingly fastener 311) may be rotated by hand and removed from shaft 111, wherein shaft 111 may be discouraged from rotating with the rotation of implement securing apparatus 132 through motor shaft locking apparatus 131 engaging shaft 111. In accordance with embodiments, the engagement of pawls 531 with toothed portion 412 of shaft 111 allows relative rotation in the opposite direction so that the operator may easily rotate implement securing apparatus 132 (and correspondingly fastener 311) with respect to shaft 111 in order to securely mount detachable implement 120. The fastener/shaft engagement implemented according to embodiments of the invention does not require fastener 311 to be tightened on shaft 111 very tight as the locking action of pawls 531 and toothed portion 412 may be utilized in discouraging loosening of implement securing apparatus 132 (e.g., fastener 311 becoming loose on shaft 111). Accordingly, torque applied by hand is sufficient for both tightening and loosening implement securing apparatus 132 of embodiments of the invention. As can be appreciated from the foregoing, motor shaft locking apparatus 131 and implement securing apparatus 132 of embodiments of tool-free implement change mechanism 130 allows an operator to interface implement securing apparatus 132 onto shaft 111, affixing detachable implement 120 thereto, by hand without need to use one or more wrenches or other, separate tools.
Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification. As one of ordinary skill in the art will readily appreciate from the disclosure of the present invention, processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized according to the present invention. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps.
Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/CN2020/127460 | 11/9/2020 | WO |
