TECHNICAL FIELD

[0001] The invention is directed broadly towards a motor guard. In particular, there is provided a modular guard for protecting the motor of a portable power tool.

BACKGROUND

[0002] Portable power tools are used for several different applications. Examples of portable power tools include hand-held construction equipment such as concreting and landscaping tools as well as hand-held gardening equipment such as whipper snippers and hedge trimmers.

[0003] Drive of a portable power tool is provided by a small motor. Combustion based two- stroke and four-stroke engines as well as electrical motors are examples of different types of motor that are typically used to power portable power tools. It is common for the same motor type to be used across several different power tools. For example, the Honda GX35 is a well-known small engine that is used to power a range of portable power tools, including construction equipment, water pumps and gardening tools.

[0004] Irrespective of application, most portable power tools share a similar stick-like design with an exposed motor located towards a first end and an operating head located at an opposing working end. This arrangement ensures that the controls of the motor are within easy reach of the operator, so that the operator can regulate the level of drive provided to the operating head, whilst also permitting simple access to interior components of the motor for maintenance and/or refueling.

[0005] Given their nature and intended use, portable power tools are subjected to harsh operating environments. The motors of portable power tools can be exposed to dust, water and other forms of external debris during use. Such exposure can hinder the working life of the engine, and reduce the reliability of the portable power tool. Furthermore, is it not uncommon for portable power tools to be roughly handled by operators, and regularly subjected to drops or impacts with walls and other surroundings. This can result in damage to the motor, rendering the power tool inoperable.

[0006] Against this backdrop, rudimentary cage guards have been developed to fit around the motor housing of portable power tools. Cage guards provide a limited level of protection against drops and impacts, however provide little to no protection from debris or liquids. [0007] Within this context, there is a need for an improved guard for protecting the motor of portable power tools or to at least provide the public with a useful choice. The present invention was conceived with these shortcomings in mind.

SUMMARY

[0008] In a first aspect, the invention provides a guard for a motor of a portable power tool, comprising an assembly of panels that interconnect to form a cover that is couplable to the motor, with the cover conforming with an external geometry of the motor so as to extend substantially therearound when coupled thereto, wherein the assembly is configured such that each of the panels is selectably detachable from one another whilst the cover remains coupled to the motor.

[0009] Preferably, the assembly of panels includes a primary panel that is adapted to mount to the motor, with the cover being couplable to the motor via the primary panel. The primary panel may be spaced from the motor by a boss. The boss may be integrally formed with the primary panel, projecting from an internal surface thereof. Alternatively, the boss may be provided as a separate component that, in use, is disposed between the primary panel and the motor.

[0010] In some embodiments, the assembly of panels includes at least one secondary panel, with each secondary panel being adapted to interconnect with the primary panel. One of the primary panel and the at least one secondary panel may include a tab and the other of the primary panel and the at least one secondary panel include an aperture, with the panels being connectable with one another by a fastener threaded through the aperture and the tab. Each secondary panel may be spaced from the motor and not mounted thereto.

[0011] Optionally, the assembly of panels may include a plurality of primary panels, with each of the primary panels being adapted to mount to the motor.

[0012] The cover may be configured to provide a barrier that protects the motor from an external operating environment. The cover may be a closed cover configured to substantially encapsulate the motor when coupled thereto. The cover may include a plurality of access ports to permit access to controls of the power tool whilst the cover is coupled thereto. The cover may include a plurality of cooling vents.

[0013] In some embodiments, the barrier may be a thermal barrier, with the cover adapted to insulate the motor from external operating temperatures when coupled thereto. [0014] The barrier may be a debris barrier, with the cover adapted to reduce build-up of debris on or within the motor arising from operation of the power tool when coupled thereto.

[0015] Alternatively or additionally, the barrier may be a splash barrier, with the cover adapted to shield the motor from liquids arising from operation of the power tool when coupled thereto.

[0016] In some embodiments, the panels may be formed from a metallic material. The panels may have an anti-corrosion coating.

[0017] In a second aspect, the invention provides a portable power tool comprising the guard as described herein.

[0018] The power tool may be a concrete vibrator.

[0019] In a third aspect, the invention provides a modular kit for forming a guard to protect a respective motor of a portable power tool, comprising a plurality of panels that are selectably interconnectable with one another to form a cover that conforms to an external geometry of a respective motor so as to extend substantially therearound when coupled thereto, wherein the plurality of panels includes a first base panel that is configured to mount to a first motor; wherein each cover formed by the kit is configured such that each of the respective panels thereof is selectably detachable from one another whilst the cover remains coupled to the motor

[0020] The kit may further comprise a second base panel that is configured to mount to a second motor having a different external geometry to the first motor, with the cover being couplable to the respective second motor via the second base panel.

BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The invention will now be described, by way of non-limiting example only, with reference to the accompanying drawings, in which:

Figure 1 is a perspective view of a guard for a motor of a portable power tool according to an embodiment of the invention, the guard comprising a cover that conforms to an external geometry of the motor;

Figure 2 is an exploded view of the guard of Figure 1 , showing four panels that interlock together to form the cover; Figure 3 is a perspective view of a base panel that is configured to mount to the motor;

Figure 4 is an outer perspective view of a side panel that is configured to interlock with the base panel of Figure 3;

Figure 5 is an inner perspective view of another side panel that is configured to interlock with the base panel of Figure 3;

Figure 6 is a perspective view of a top panel that is configured to mount to the motor and to interlock with the side panel of Figure 5;

Figure 7 is an exploded perspective view of the guard of Figure 1 , schematically showing the coupling of the guard to a motor; and

Figure 8 is a perspective view of a portable power tool having the guard of Figure 1 fitted thereto.

DETAILED DESCRIPTION

[0022] In the following detailed description, reference is made to accompanying drawings which form a part of the detailed description. It will be readily understood that the aspects of the present disclosure, as generally described herein and illustrated in the drawings may be arranged, substituted, combined, separated and designed in a wide variety of different configurations, all of which are contemplated in this disclosure.

[0023] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although any methods and materials similar or equivalent to those described herein can also be used in the practice or testing of the present invention, a limited number of the example methods and materials are described herein.

[0024] In general terms, the guard 100 shown in the Figures comprises a removable cover 102 for protecting the motor 104 of a portable power tool 106. The cover 102 is formed from an assembly of panels 108, 110, 112, 114 that interconnect together to form the cover 102. The panels 108, 110, 112, 114 of the cover 102 are shaped to conform to an external geometry of the motor 104. In this way, when the cover 102 is fitted to the power tool 106, the cover 102 extends substantially around the motor 104 to form a closed cover 102 that substantially encapsulates the motor 104 and protects it from the external operating environment.

[0025] Each of the panels 108, 110, 112, and 114 is designed to be selectably detachable from one another, whilst the remaining panels of the cover 102 remain coupled to the motor 104. In this way, access to serviceable internal components of the motor 104 such as carburetors, air filters and the like is permitted without requiring the guard 100 to be completely removed from the power tool 106. Likewise, re-fueling and/or oil changes can quickly and safely be completed whilst the guard 100 is fitted thereto. Accordingly, the guard 100 provides significant protection to the motor 104 without reducing the ease of use and/or maintenance of the power tool 106.

[0026] In this specification, the term "portable power tool" is taken to encompass any form of hand-held power tool that is typically used outdoors. Non-limiting examples include concrete working tools such as screed, spreaders, trowels and vibrators as well as gardening tools such as hedge trimmers and whipper-snippers. In particular, whilst the guard 100 is described herein as being suitable for use with a concrete vibrating power tool, it is understood that the guard 100 is not limited to power tools for this application only.

[0027] In this specification, the term "motor" is taken to refer to a machine that drives movement of the operating head of the power tool 106. Such machines typically enclosed within a box-like housing that surrounds the moving components. The housing generally has several ports that provide access to serviceable components for required regular maintenance. In particular, whilst the motor 104 as described herein and illustrated in the Figures is a small internal-combustion engine, it is understood that the guard 100 is also suitable for use with electric engines including battery powered electric engines and other forms of engine.

[0028] With particular reference to Figures 1 to 2, the cover 102 of the guard 100 is a shell-like enclosure that, in use, is configured to wrap around a periphery of the motor 104. The cover 102 defines a closed enclosure that is designed to encapsulate the motor 104 within. Accordingly, with the motor 104 being encapsulated by the cover 102, the guard 100 therefore serves as a protective barrier that can protect the motor 104 from its external operating environment. For example, the cover 102 reduces the impact forces that are transmitted to the motor 104 in the event that the power tool 106 is dropped or otherwise impacts an external object. To this end, it is envisaged that the cover 102 may be formed by an energy-absorbing material. [0029] The term "closed cover" is understood to mean that the cover 102 overlays a substantial proportion of the external surface area of the motor 104 that is encapsulated therein, with any openings/apertures within the cover 102 being small in comparison to the surface area of the panels thereof. This is distinct from existing "cage" type guards that feature large exposed openings between the outer roll cage frames. Because the cover 102 is a closed cover, it serves as a splash barrier or shield to direct liquids away from the motor. Likewise, the cover 102 can also serve as a debris barrier to direct particle matter away from the motor 104. For example, the cover 102 can prevent or at least reduce the possibility of splashes or liquid concrete and/or debris fragments from entering the housing of the motor 104 when used to power a concrete vibrating tool. Such liquids can be damaging to internal electrical components of the motor 104 whilst debris can become wedged between moving mechanical components. Furthermore, the cover 102 can have an anti-corrosive coating. Such a coating is beneficial to prevent rusting of the cover 102 itself if repeatedly exposed to high levels of moisture for extended periods.

[0030] The cover 102 can also serve as a thermal barrier. What is meant by this is that the cover 102 can act as a heat shield, preventing or reducing sunlight from directly reaching the motor 104 housed therein. Furthermore, the cover 102 is preferably made from an insulative material or is at least coated in an insulative coating. For example, the cover 102 may be made from steel and coated with a reflective paint. In this manner, the internal temperature of the motor 104 may be lower when the tool 106 is operated in sunny conditions with the guard 100 fitted than if the guard 100 was not fitted.

[0031] The guard 100 is configured to ensure that access to important controls and components thereof is not negatively affected. Accordingly, it is understood that the cover 102 need not be completely sealed. As shown in the Figures, the cover 102 extends radially around the motor 104, however has open front and rear faces 116, 118. The open rear face 118 permits user access to parts of the motor 104 such as the fuel tank and started cord, whilst the open front face 116 permits axial extension of the working head of the tool 106 therethrough. The open ended configuration of the cover 102 can also permit easy removal of any debris that may accumulate between the guard 100 and the motor 104, without the need to decouple the guard 100 therefrom.

[0032] Best shown in Figure 2, the cover 102 is provided as an assembly of panels including at least one primary panel that is directly mountable to the motor 104. The cover 102 is couplable to the motor 104 via the at least one primary panel. The remaining panels of the assembly (i.e. those that are not considered to be primary panels) are considered to be secondary panels and are not directly mounted to the motor 104. Beneficially, because the secondary panels are not mounted to the motor 104, they can be spaced/held at a distance therefrom. Such spacing creates a gap G (as shown in Figure 8) between the motor 104 and the secondary panel, assisting to dissipate heat generated from operation of the motor 104.

[0033] In the embodiment shown in the Figures, the cover comprises a base panel 108, opposing side panels 110, 112 and a top panel 114. The base panel 108 and the top panel 114 are primary panels, with each being directly mountable to the motor 104. The two side panels 110,112 are secondary panels, and are secured in position in-situ about the motor 104 via respective connections with the base panel 108 and top panel 114. Said connections are provided by respective connection units formed by connection members of the primary and secondary panels. It is understood, however, that the cover 102 does not need to comprise four panels only, and that in other embodiments (not illustrated) the cover may comprise as little as two panels, whilst other embodiments still may include more than four panels.

[0034] Shown prominently in Figure 1, access ports 120 are disposed about the surface of the cover 102. The access ports 120 provide openings through which a user of the power tool 106 may operate controls of the motor 104 whilst the cover 102 is coupled thereto. The ports 120 can also provide access to an internal volume of the motor 104, to enable servicing and/or inspection of components therein. For example, the ports 120 can provide access to the carburetor and air filters of the motor 104. In this way, the usability of the motor 104 is not affected, and it is not necessary for the operator to remove the cover 102 or components thereof in order to control and/or actuate the motor 104. Whilst not shown in the Figures, it is also contemplated that at least some of the access ports 120 may be provided with a seal such as a dust flap, with the seal being removed by the user when access to the port 120 is required. The seals may, for example, be tethered to the panel within which the port is located.

[0035] Additionally, the cover 102 also includes a plurality of cooling vents 122. The cooling vents 122 facilitate the dispersion of heat from the internal volume of the motor 104, optimizing the internal cooling of the components thereof. The cooling vents 122 are also adapted to direct the exhaust of warm air from the motor 104 away from the user during use. With reference to the embodiment shown in the Figures, the cooling vents 122 are provided as slots within each of the primary panels 108 and 114 include cooling vents 122, whilst the secondary panels 110 and 112 do not - this being because the secondary panels 110 and 112 are spaced away from the motor 104 by gap G. It is understood however, that the shape and location of the cooling vents 122 is dependent on the configuration of the motor 104 itself - with it being preferable to align the cooling vents 122 with corresponding 'breathing' openings within the housing of the motor 104 itself.

[0036] Each of the panels 108, 110, 112 and 114 will now be described in detail with reference to Figures 3 to 6.

[0037] With reference to Figure 3, the base panel 108 is configured as a dish that provides a seat for the motor 104 to be received therein. In particular, the base panel 108 comprises a central platform 124 and an upstanding peripheral lip 126 that projects upwardly therefrom. In use, the platform 124 provides a substantially flat resting surface for the power tool 106, with the lip 126 cupping around the motor 104 thereof and supporting it therein. Accordingly, it is understood that the base panel 108 is shaped to conform to a particular shape or external geometry of motor 104 - that is, there may be different base panels 108 depending on which motor 104 the guard 100 is designed to be coupled to.

[0038] The platform 124 is adapted to mount directly to the housing of the motor 104. Specifically, two bosses 128 are provided on an inner face of the platform 124. As shown, the bosses 128 are integrally formed with the platform 124. It is understood, however, that the bosses 124 can, alternatively, be provided as separate components, installable between the platform 124 and the motor 104. In a further alternative (as shown in Figure 7) each boss 128 can comprise both an integrally formed projection as well as a separate spacer component. Each boss 128 includes a central aperture 130 that is arranged to coaxially align with mounting holes of the motor 124. The central aperture 130 extends through the panel 108 such that a screw S is insertable therethrough. It is understood that the number and arrangement of the bosses 128 is selected to suit the external geometry of the motor 124. In this way, inserting screws S through the boss and into the mounting holes fixedly mounts the base panel 108 to the motor 104 - as is shown in Figure 7. Advantageously, when the guard 100 is coupled to the motor 104, the bosses 128 space the platform 124 away from the underside of the motor 124 and thereby permit airflow. This airflow assists in ensuring that cooling of the motor 104 is not impeded by installation of the guard 100.

[0039] Returning to Figure 3, the lip 126 comprises a pair of ramped surfaces 132 that extend along opposing side edges of the platform 124 and a pair of end walls 134 that extend along the front and rear edges thereof. The ramped surfaces 132 are adapted to extend away from the motor 104, so as to provide a cooling channel between the motor 104 and the guard 100. The end walls 134 extend substantially vertically from the platform 124, to thereby limit axial movement of the motor 104 relative to the guard 100. An additional boss 128 is provided on the rear end wall 134.

[0040] A plurality of tongue-like tabs 136 project upwardly from the lip 126. The tabs 136 are a connection member that form part of the connection unit that provides the interlocking of the primary panels and the secondary panels. As shown, a pair of tabs 136 extend from each of the ramped surfaces 132 along the sides of the base panel 108. It is also contemplated, however, that in other embodiments the tabs may also/alternatively extend from the end walls 134. Each tab 136 includes a central hole within which a fastener F is receivable - the connection of the secondary panels to the primary panels will be discussed later with particular reference to Figure 7.

[0041] Turning now to Figures 4 and 5, the side panels 110, 112 will be described. As shown in each of the Figures, the profile of the side panels 110, 112 is identical to each other - owing to the external geometry of the motor 104 to which the guard 100 is designed to couple. As a result of this, the side panels 110, 112 are interchangeable with one another, which is useful during assembly and manufacturing of the guard 100. It is understood, however, that in other cases the side panels 110, 112 may not be identical. The body of each side panel 110, 112 includes central web portion 138 that is disposed between upper and lower flanges 140, 142. In the illustrated embodiment, the upper flange 140 of each side panel is angled inwardly with respect to the planar web portion 138 and lower flange 142. A pair of tabs 136 project from the upper flange 140, substantially perpendicular to the body of the panel 110, 112.The tabs 136 of the side panel are configured to form a connection with the top panel 114.

[0042] Apertures 144 are located within the lower flange 142 of the panels 110, 112, and provide the other part of the connection unit described hitherto. As is best shown in Figure 7, each aperture 144 is arranged to form a connection unit with an abutting tab 136 of the base 108. Specifically, each tab 136 is arranged directly inside of a corresponding aperture 144 of the base 108, so as to provide a smooth external surface of the cover 102. It is envisaged that at least one of the aperture 144 or tab 136 of each connection unit is threaded, such that insertion of a threaded fastener F through the connection pair securely interlocks the respective side panel 110, 112 to the base 108. The side panels 110, 112 can quickly and easily be detached from the base 108 by removing the respective fastener F. In an alternative embodiment, it is contemplated the base 108 and the side panels 110, 112 may include other intermeshing connection members that secure together via a releasable snap-fit. [0043] Turning now to Figure 6, which shows the top panel 114 of the cover 102. The top panel 114 has a stepped profile that includes a central portion 146 and two side portions 148 that together form a top-hat shape that is adapted to sit as a lid atop the motor 104. As such, it is understood that the profile of the top panel 114 conforms with the upper side of the housing of the motor 104, and that, depending on the shape of the motor itself, the profile of the top panel 114 may differ from that illustrated. To this end, different top panels 114 may be provided to fit different shapes/types of motor 104.

[0044] Apertures 144 are disposed within each of the side portions 148. The apertures 144 of the top panel 114 are arranged to coaxially align above tabs 136 of the respective side panels 110, 112, and form a connection unit therewith. In this manner, each of the side panels 110, 112 is securely interlocked with the top panel 114, which in turn is coupled to the motor 104. Accordingly, each side panel 110, 112 can be quickly and easily removed from the cover 102 by removing the fasteners F that attach it to the base panel 108 and top panel 114 - whilst the remaining panels remain coupled to the motor 104. Likewise, removal of either one of the base panel 108 or the top panel 114 is permitted by removing the fasteners F that attach said panel to the side panels 110, 112 and the mounting screws S that couple said panel to the motor 104 - whilst the remainder of the cover 102 remains in place.

[0045] Like the base panel 108, the top panel 114 is a primary panel that is designed to mount directly the motor 104. Whilst not clear in Figure 6 (but illustrated in Figure 7), an inner face of each central portion 146 includes a boss 128. The boss 128 is located so as to coincide with a corresponding mounting hole of the motor 104. In use (i.e. when the guard 100 is coupled to the motor 104) the boss 128 spaces the top panel 114 from the upper surface of the motor 104, so as to permit airflow there between. The relative spacing of each of panels 108, 110, 112, 114 from the motor 104 provide respective gaps G that together form an air jacket 149 between the motor 104 and the cover 102. The air jacket 149 substantially envelopes the motor 104, extending around a circumference thereof. This air jacket 149 facilitates air flow around the motor 102, encouraging the dissipation of heat energy from within the motor 104 - through both the open end faces 116, 118 and the cooling vents 122 of the guard.

[0046] Whilst not limiting, it is envisaged that the guard 100 as described herein can be provided as a modular kit 150. The kit 150 includes at least one base panel 108 as described herein, and at least one secondary panel 110/112. Together, the panels of the kit 150 can be assembled to form a cover 102 that is couplable to a particular type of motor 104. As previously described, the base panel 108 has a particular geometry enabling it to be directly mounted to the motor 104, whilst the secondary panel(s) are designed to interlock with the base panel 108. Advantageously, it is contemplated that the kit also includes at least one second base panel 108' that is designed to mount to a different type of motor 104' - permitting the selectable assembly of several different versions of cover 102 suited for the selected motor type 104/104'. The second base panel 108' is shaped to conform to the motor 104', in particular the profile or shape of the panel 108' and the location of the mounting boss 128. Further, because the secondary panels 110, 112 are not directly mounted to the motor, the secondary panel(s) 110/ 112 can be shared between the different versions of cover 102 formed from the kit 150, designed to fit around similarly sized motors 104. This modularity is facilitated because the arrangement and spacing between the connection members 136/144 of the different base panels 108' remains standard or constant.

[0047] Turning finally to Figure 8, which shows the guard 100 installed upon a concrete vibrator tool 106. As shown in the Figure, the working head 152 of the tool 106 extends axially through and away from the open front face 116 of the guard 100, whilst the motor 104 is substantially encapsulated within and protected by the cover 102 of the guard 100 that extends radially therearound. Whilst described hitherto as an accessory that is selectably installable onto a power tool 106 as an aftermarket improvement thereto, it is contemplated that the guard 100 can, alternatively, be factory fitted to a power tool 106 and sold together therewith.

[0048] Summarily, it is to be understood that guard 100 as described herein provides several performance advantages and durability improvements for portable power tools 106. For example, the splash and debris barrier afforded by the cover 102 of the present invention provides significantly increased protection for the motor 104 than existing cage guards and results in a more reliable tool. Furthermore, the simplicity of assembly and ability to remove singular panels thereof without the need to remove the entire guard mean that such protection is provided without comprising usability and accessibility of the power tool 106.

[0049] The reference in this specification to any prior publication (or information derived from it), or to any matter which is known, is not, and should not be taken as an acknowledgment or admission or any form of suggestion that that prior publication (or information derived from it) or known matter forms part of the common general knowledge in the field of endeavor to which this specification relates. [0050] Throughout this specification and the claims which follow, unless the context requires otherwise, the word ‘comprise’, and variations such as ‘comprises’ and ‘comprising’, will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps.

LEGEND