Handheld power tool with safety switch

Abstract

A handheld power tool (1) is disclosed, comprising a power tool body (3), a tool (2), a power source (4) configured to supply power to the tool (2), a switch (10) configured to set the power tool (1) to an activated or deactivated state, and an elongated handle (20). The elongated handle (20) comprises a trigger element (30) movably disposed relative to the elongated handle (20), the trigger element (30) moving relative to the handle (20) when a person grips the handle (20). The switch (10) is disposed on the power tool body (3). The power tool (1) comprises a mechanism (7) operably connected to the trigger element (30). The mechanism (7) is configured such that a first mechanism member (11) of the mechanism (7) moves in a direction (d1) toward the switch (10) when the handle (20) is gripped.

Description

[Technical Field]

[0001] The present disclosure relates to a handheld power tool that includes a switch configured to set the power tool to an activated or deactivated state. [Background technology]

[0002] A handheld power tool is a tool intended to be supported by one or both hands of a user during operation. Furthermore, handheld power tools include tools that can be powered by power sources other than simple labor. Power sources may include, for example, combustion engines, electric motors, pneumatic motors, etc. There are many types of power tools available on the market today. Examples include chainsaws, circular saws, trimmers, hedge trimmers, string trimmers, brush cutters, multi-tools, etc. Power tools are used, for example, in industry, construction, gardening, for household tasks, and around the home for purposes such as cutting, shaping, sanding, grinding, routing, polishing, etc.

[0003] Various types of power tools involve several interrelated issues. One issue is safety. That is, power tools may include sharp tools and a powerful power source for powering the tools. Therefore, some power tools include a safety switch that sets the power tool to an activated or deactivated state based on whether a user is gripping the handle of the power tool. Such handles are often provided with a safety mechanism that ensures that the power tool is properly held during operation, for example, that the power tool is held with both hands when in use. Certain power tools, such as hedge trimmers, may be rotated in various directions during operation, and therefore these power tools may be provided with handles and safety switches that allow the user to hold the power tool in several positions, including both horizontal and vertical positions.

[0004] Safety switches of the type described above can significantly enhance safety during the handling of power tools. However, many of these features and functions add cost and complexity to power tools, and in today's consumer market, it is generally advantageous when products such as power tools have conditions and / or characteristics that allow them to be manufactured and assembled in a cost-effective manner.

[0005] Furthermore, an issue when designing a power tool with a safety switch is the reliability and robustness of the safety switch, since power tools typically operate in demanding environments with a lot of dust, debris, water, vibration, etc., and malfunction of the safety switch can cause a dangerous situation.

[0006] Further common considerations when designing power tools are compactness and ease of use, i.e., it is advantageous if the power tool is designed to allow the user to intuitively operate the power tool, and small power tools can be easier and less cumbersome to use than bulkier power tools. Summary of the Invention [Problem to be solved by the invention]

[0007] It is an object of the present invention to overcome or at least mitigate at least some of the problems and disadvantages mentioned above. [Means for solving the problem]

[0008] According to a first aspect of the present invention, the above object is achieved by a handheld power tool comprising a power tool body, a power source configured to power the tool, a switch configured to activate or deactivate the power tool, and an elongated handle to be held by a user of the power tool. The elongated handle comprises a trigger element extending along at least a portion of the elongated handle and movably disposed relative to the elongated handle, the trigger element moving relative to the handle when the user grips the handle. The switch is disposed on the power tool body. The power tool comprises a mechanism operably connected to the trigger element, the mechanism being configured such that a first mechanism member of the mechanism moves toward the switch when the handle is gripped.

[0009] The mechanism is configured such that when the handle is gripped, a first mechanical member of the mechanism moves in a direction toward the switch, thereby providing a power tool with conditions for consistent and reliable activation and deactivation of the switch.

[0010] Furthermore, since the switch is located on the power tool body, conditions are provided for shielding the switch from dust, debris, water, shock, vibration, etc. In this way, a more robust and reliable power tool can be provided. A further result of these features is that a safer power tool can be provided.

[0011] In addition to this, since the switch is located on the power tool body, provisions are made for a smaller power tool, which is therefore easier to use. SUMMARY OF THE INVENTION Accordingly, there has been provided a power tool which overcomes or at least mitigates at least some of the problems and disadvantages set forth above.

[0012] Optionally, the mechanism includes a second mechanism member connected to the trigger element and the first mechanism member, the first mechanism member configured to move relative to the switch upon movement of the second mechanism member, thereby providing a power tool with conditions for consistent and reliable activation and deactivation of the switch in a simple and efficient manner.

[0013] Optionally, the mechanism is configured such that pivotal movement of the second mechanism member causes the first mechanism member to move relative to the switch. This provides a power tool with conditions for consistent and reliable activation and deactivation of the switch. Furthermore, the power tool provides conditions for activation of the switch upon movement of the trigger element in several directions relative to the elongated handle. In this way, the power tool provides conditions that allow a user to grip the elongated handle in a variety of gripping directions simply and efficiently during operation of the power tool.

[0014] Optionally, the second mechanism member is pivotally disposed about the first pivot axis, thereby providing a power tool with a simple and efficient provision for consistent and reliable activation and deactivation of the switch.

[0015] Optionally, the second mechanism member is pivotally disposed about a second pivot axis transverse to the first pivot axis, thereby providing a power tool with provisions for consistent and reliable activation and deactivation of the switch. Furthermore, the power tool is provided with provisions for activation of the switch upon movement of the trigger element in several directions relative to the elongated handle. In this way, a power tool is provided with provisions that allow a user to grip the elongated handle in various gripping directions simply and efficiently during operation of the power tool.

[0016] Optionally, the trigger element includes an opening (37) and the second mechanism member includes a knob that protrudes into the opening, thereby providing a simple, efficient, and reliable transmission of motion between the trigger element and the second mechanism member. Furthermore, a power tool is provided that has provisions for switch activation upon movement of the trigger element relative to the elongated handle in several directions. In this way, a power tool is provided that has provisions that allow a user to grip the elongated handle in various positions simply and efficiently during operation of the power tool.

[0017] Optionally, the second mechanism member includes a recess, and the second mechanism member is movable to a position where a section of the first mechanism member protrudes into the recess, thereby providing a power tool with conditions for consistent and reliable activation and deactivation of a switch in a simple, reliable, and cost-effective manner.

[0018] Optionally, the first mechanism member moves in a direction toward the switch when the section of the first mechanism member moves out of the recess, thereby providing a power tool with conditions for consistent and reliable activation and deactivation of a switch in a simple, reliable, and cost-effective manner.

[0019] Optionally, the second mechanism member includes an abutment surface adjacent the recess, the second mechanism member configured to move the first mechanism member toward the switch upon abutting contact between the abutment surface and the first mechanism member. This provides a power tool with a condition for consistent and reliable activation and deactivation of the switch in a simple, reliable, and cost-effective manner. Furthermore, the power tool provides a condition for a distinct trigger point of the trigger element, where the position of the trigger element relative to the elongated handle activates the switch. Additionally, these features enable movement of the trigger element past the trigger point. In this way, the switch can be quickly and efficiently activated by simply gripping the elongated handle, avoiding unintentional deactivation of the switch, which can occur, for example, by loosely gripping the elongated handle, thereby providing a more user-friendly power tool.

[0020] Optionally, the abutment surface is curved, bowl-shaped, or both. This provides a power tool with a defined trigger point for the trigger element, where the position of the trigger element relative to the elongated handle activates the switch. Additionally, these features allow movement of the trigger element past the trigger point. In this way, the switch can be quickly and efficiently activated by simply gripping the elongated handle, avoiding unintentional deactivation of the switch, which can occur, for example, by loosely gripping the elongated handle, thereby providing a more user-friendly power tool.

[0021] Optionally, the abutment surface surrounds the recess. This provides a power tool with a provision for a distinct trigger point of the trigger element, where the position of the trigger element relative to the elongated handle activates the switch. Additionally, these features allow movement of the trigger element past the trigger point. This provides a more user-friendly power tool, as the switch can be quickly and efficiently activated by simply gripping the elongated handle, avoiding unintentional deactivation of the switch, which can occur, for example, by loosely gripping the elongated handle. Furthermore, a power tool is provided with a provision for switch activation upon movement of the trigger element relative to the elongated handle in several directions. This provides a power tool with a provision that allows a user to grip the elongated handle in various gripping directions simply and efficiently during operation of the power tool.

[0022] Optionally, the power tool includes a resilient member biasing the first mechanical member toward the second mechanical member, thereby providing a power tool with conditions for consistent and reliable activation and deactivation of the switch in a simple, reliable, and cost-effective manner. Additionally, biasing the first mechanical member toward the second mechanical member provides a more positive and reliable deactivation of the switch when the user releases their grip on the elongated handle.

[0023] Optionally, the first mechanism member is spherical or elliptical, thereby providing a power tool with conditions for consistent and reliable activation and deactivation of a switch in a simple, reliable, and cost-effective manner.

[0024] Optionally, the mechanism is located on the power tool body, thereby providing provisions for shielding the mechanism from dust, debris, water, shock, vibration, etc. In this way, it is possible to provide a more robust and reliable power tool. In addition, since the mechanism is located on the power tool body, provisions are provided for a more compact power tool, which is therefore easier to use.

[0025] Optionally, the elongate handle includes a gripping portion for being grasped by a person, and the trigger element has an actuation portion that protrudes from the gripping portion of the elongate handle, thereby providing more reliable and accurate activation and deactivation of the switch when a user is grasping the elongate handle and when the user releases their grip on the elongate handle.

[0026] Optionally, the gripping portion of the elongated handle is curved to at least partially surround an area, and the actuation portion protrudes through a slot extending on the gripping portion of the elongated handle and faces the area, thereby providing a power tool with provisions for switch actuation upon movement of the trigger element in various directions relative to the elongated handle, thereby providing a power tool with provisions that allow a user to grip the elongated handle in various gripping directions simply and efficiently during operation of the power tool.

[0027] Optionally, the trigger element is a continuous, one-piece body, which provides a trigger element that is durable and has the conditions and characteristics to be manufactured and assembled in a cost-effective manner.

[0028] Optionally, the switch can be set to a first state that sets the power tool to a deactivated state or a second state that sets the power tool to an activated state. Such switches, for example, mechanically actuated microswitches, are fail-safe, small, and available at low cost.

[0029] Optionally, the power tool includes a main handle having a main trigger for controlling the speed of the power source. Thus, the switch may be a safety switch connected to the main trigger such that the main trigger is disabled when the safety switch is in a first state and the main trigger is enabled when the switch is in a second state.

[0030] Optionally, the power tool includes interlocking guide surfaces for guiding the direction of movement of the trigger element relative to the handle, thereby providing a power tool with the conditions for consistent and reliable actuation and deactuation of a switch in a simple, reliable and cost-effective manner.

[0031] Optionally, the interfitting guide surfaces include an aperture and a guide pin projecting into the aperture, thereby providing a power tool with provisions for consistent and reliable activation and deactivation of the switch in a simple, reliable, and cost-effective manner.

[0032] Optionally, the power tool is a hedge trimmer, a string trimmer, or a brush cutter. Further features and advantages of the present invention will become apparent upon review of the appended claims and the following detailed description.

[0033] The various aspects of the present invention, including its particular features and advantages, will be readily understood from the illustrative embodiments discussed in the following detailed description and the accompanying drawings. [Brief explanation of the drawings]

[0034] [Figure 1] 1 is a perspective view of a handheld power tool according to some embodiments. [Figure 2] 2 is a cross-sectional view of a portion of the power tool shown in FIG. 1; [Figure 3] 3 is a cross-sectional view of some components of the power tool shown in FIGS. 1 and 2; [Figure 4]4 is a cross-sectional view of the components shown in FIG. 3 with the trigger element moved to an actuated position relative to the elongated handle of the power tool. [Figure 5] FIG. 5 is a perspective view of a switch assembly of the power tool according to the embodiment shown in FIGS. [Figure 6] FIG. 6 is a cross-sectional view of the switch assembly shown in FIG. 5. [Figure 7] 7 is a cross-sectional view of the switch assembly shown in FIG. 6 with the second mechanism member pivoted to an actuated position. [Figure 8] 5 is a cross-sectional view of the elongated handle of the power tool according to the embodiment shown in FIGS. 1 to 4. FIG. [Figure 9] 9 is a cross-sectional view of the elongate handle shown in FIG. 8 with the trigger element moved to an actuated position. DETAILED DESCRIPTION OF THE INVENTION

[0035] Aspects of the present invention will now be more fully described. Like numbers refer to like elements throughout. Well-known functions or constructions are not necessarily described in detail for the sake of brevity and / or clarity.

[0036] 1 shows a perspective view of a handheld power tool 1 according to some embodiments. According to the embodiment shown, the handheld power tool 1 is a hedge trimmer. According to further embodiments, the handheld power tool 1 referred to herein is another type of handheld power tool, such as a string trimmer, brush cutter, power cutter, chainsaw, circular saw, multi-tool, etc.

[0037] The characterization of handheld power tool 1 as "handheld" means that handheld power tool 1 is configured to be supported by one or both hands of a user during operation. Handheld power tool 1 according to the illustrated embodiment is configured to be supported by both hands of a user during operation, as described further herein. Handheld power tool 1 is referred to as "power tool 1" in several places herein for brevity and clarity.

[0038] Power tool 1 includes power tool body 3, tool 2, and a power source configured to power tool 2. Power tool body 3 houses several components and systems of power tool 1, such as the power source, as described further herein. Power tool body 3 may further include several additional components not visible in FIG. 1 that are typically found on power tools and therefore need not be described in detail here. These components include, but are not limited to, a gearbox, an attachment for attaching tool 2 to power tool 1, electrical wiring circuitry, an electronic controller for controlling the operation of power tool 1, external buttons, levers, and various controls. In the alternative form shown, tool 2 is a saw-tooth blade for cutting hedge branches, i.e., a reciprocating cutting tool.

[0039] The power tool 1 comprises an elongated handle 20 that is held by a person using the power tool 1. Furthermore, the power tool 1 comprises a main handle 5 having a main trigger 6 for controlling the speed and operation of the power source of the power tool 1. Thus, according to the embodiment shown, the handheld power tool 1 is configured to be supported by both hands of a user during operation, i.e., one hand gripping the elongated handle 20 and the other hand gripping the main handle 5.

[0040] According to the illustrated embodiment, the elongated handle 20 may be referred to as the front secondary handle, and the main handle 5 may be referred to as the rear primary handle. As shown in FIG. 1 , the elongated handle 20 is elongated and bent into a curved shape to form a continuous rounded rectangular shape and enclose an area and is attached to the power tool body 3. In operation, the elongated handle 20 may be grasped by a person using the power tool 1 at essentially any position along its length. For example, a person using the power tool may grasp the elongated handle 20 at a first lateral region, a middle region, or a second lateral region. In this manner, a user may operate the power tool 1 in a variety of orientations, as further described herein.

[0041] FIG. 2 shows a cross-sectional view of a portion of the power tool 1 shown in FIG. 1. In FIG. 2, some components of the power tool 1 have been removed for visibility and clarity. A portion of the power tool body 3 and a portion of the tool 2 of the power tool 1 are visible in FIG. 2. Additionally, the power source 4 of the power tool 1 is visible in FIG. 2. According to the embodiment shown, the power source 4 is an electric motor powered by a battery. FIG. 1 shows a battery 40 of the power tool 1. According to further embodiments, the power source 4 may be powered by another type of configuration, such as a power cord. Furthermore, according to further embodiments, the power source 4 referred to herein may be a type of power source other than an electric motor, such as a combustion engine, a pneumatic motor, etc.

[0042] Additionally, in Figure 2, a cross section of the elongate handle 20 is seen. As seen in Figure 2, the elongate handle 20 includes a trigger element 30 that extends along at least a portion of the elongate handle 20. The trigger element 30 is movably positioned relative to the elongate handle 20 such that when a person grasps the elongate handle 20, the trigger element 30 moves relative to the elongate handle 20, as described further herein.

[0043] 2 also shows the switch 10 and mechanism 7 of the power tool 1. As will be described further herein, the switch 10 is operably connected to the trigger element 30 via the mechanism 7. In other words, the mechanism 7 operably connects the trigger element 30 and the switch 10. The switch 10 is configured to set the power tool 1 to an activated or deactivated state based on the position of the trigger element 30. The switch 10, as seen in FIG. 2, is disposed on the power tool body 3.

[0044] FIG. 3 shows a cross-sectional view of some components of the power tool 1 shown in FIGS. 1 and 2. A handle assembly 20' and a switch assembly 10' of the power tool are visible in FIG. 3. The handle assembly 20' includes an elongated handle 20, and the switch assembly 10' includes a switch 10. The switch assembly 10' and the handle assembly 20' are configured to be attached to the power tool body 3 of the power tool 1 shown in FIGS. 1 and 2. The switch assembly 10' and the handle assembly 20' may be rigidly attached to the power tool body 3 of the power tool 1. Hereinafter, unless otherwise specified, reference will be made simultaneously to FIGS. 1 to 3.

[0045] The switch assembly 10' includes a protrusion 46, and the handle assembly 20' includes a recess 48. The protrusion 46 is formed as a guide pin and is configured to protrude into the recess 48 of the handle assembly 20' when the switch assembly 10' and the handle assembly 20' are in an assembled state, as shown in FIG. 3 . The protrusion 46 and the recess 48 facilitate assembly and alignment of the switch assembly 10' and the handle assembly 20'. According to the illustrated embodiment, the switch assembly 10' includes two protrusions 46, and the handle assembly 20' includes two recesses 48. However, only one of the protrusions 46 and one of the recesses 48 are visible in FIG. 3 . According to further embodiments, the switch assembly 10' may include one or more recesses, and the handle assembly 20' may include one or more protrusions configured to protrude into the recess of the switch assembly 10' when the switch assembly 10' and the handle assembly 20' are in an assembled state.

[0046] The elongated handle 20 includes a grip portion 21 that is gripped by a person. The trigger element 30 has an actuation portion 31 that protrudes from the grip portion 21 of the elongated handle 20. The grip portion 21 of the elongated handle 20 is bent to at least partially surround region A. The actuation portion 31 protrudes from a slot 22 that extends over the grip portion 21 of the elongated handle 20 and faces region A. The trigger element 30 is movably disposed in the slot 22. In FIG. 3 , the trigger element 30 is shown in an inactivated position. As described further herein, the trigger element 30 is configured to assume the inactivated position when not subjected to an external force, such as the gripping force of a user's hand.

[0047] Also visible in FIG. 3 is second mechanism member 12 of mechanism 7. Second mechanism member 12 of mechanism 7 is operably connected to trigger element 30 and configured to move upon movement of trigger element 30. According to the embodiment shown, trigger element 30 includes an opening 37, and second mechanism member 12 includes knob 16 that protrudes into opening 37 of trigger element 30. In this manner, second mechanism member 12 is operably connected to trigger element 30. According to further embodiments, second mechanism member 12 of mechanism 7 may be operably connected to trigger element 30 in another manner. By way of example, second mechanism member 12 may include an opening, and trigger element 30 may include a knob that protrudes into the opening of second mechanism member 12 of mechanism 7.

[0048] Figure 4 shows a cross-sectional view of the components shown in Figure 3 with the trigger element 30 moved to an activated position relative to the elongate handle 20. In Figure 4, the trigger element 30 is shown in a position corresponding to a situation where a user grasps a central portion p0 of the gripping portion 21 of the elongate handle 20. The mobility of the trigger element 30 relative to the different portions p0 of the gripping portion 21 of the elongate handle 20 and the elongate handle 20 is further described with reference to Figures 8 and 9 below.

[0049] As seen in FIG. 4 , second mechanism member 12 of mechanism 7 moves as a result of movement of trigger element 30 to the actuated position. According to the embodiment shown, second mechanism member 12 is pivotally disposed relative to switch assembly 10′ about a first pivot axis ax1 and a second pivot axis ax2, with second pivot axis ax2 transverse to first pivot axis ax1. As described further herein, according to the embodiment shown, second pivot axis ax2 is perpendicular to first pivot axis ax1. Additionally, second pivot axis ax2 extends through first pivot axis ax1.

[0050] According to further embodiments, second mechanism member 12 may be movably positioned relative to switch assembly 10′ in another manner, such as about a single pivot axis ax1, ax2. The position of second mechanism member 12 of mechanism 7 shown in FIG. 4 is referred to below as the actuated position, although second mechanism member 12 of mechanism 7 and trigger element 30 of elongate handle 20 are movable to different actuated positions, as further described below.

[0051] FIG. 5 shows a perspective view of the switch assembly 10′ of the power tool 1 according to the embodiment shown in FIGS. 1-4. In FIG. 5, the second mechanism member 12 of the mechanism 7 is shown in the inactivated position. As can be clearly seen in FIG. 5, the knob 16 of the second mechanism member 12 has a curved convex shape. Furthermore, according to the illustrated embodiment, the opening 37 of the trigger element 30 shown in FIGS. 4 and 5 has a matching curved concave shape. In this manner, the interface between the knob 16 and the opening 37 allows for angular displacement of the second mechanism member 12 relative to the opening 37 of the trigger element 30 in a simple, reliable, and efficient manner.

[0052] Figure 6 shows a cross section of the switch assembly 10' shown in Figure 5. In Figure 6, the cross section is taken through a plane that includes the second pivot axis ax2 of the second mechanism member 12. Also in Figure 6, the cross section is taken through a plane that is perpendicular to the first pivot axis ax1 of the second mechanism member 12. In Figure 6, the second mechanism member 12 of the mechanism 7 is shown in the unactuated position.

[0053] As seen in Figure 6, mechanism 7 includes a first mechanism member 11. As described further herein, mechanism 7 is configured such that when elongated handle 20 is gripped, first mechanism member 11 of mechanism 7 moves in direction d1 toward switch 10. According to the embodiment shown, second mechanism member 12 is in abutting contact with first mechanism member 11. Thus, according to the embodiment shown, second mechanism member 12 is connected to trigger element 30 and first mechanism member 11 shown in Figure 4 by being in abutting contact with trigger element 30 and first mechanism member 11.

[0054] More specifically, according to the embodiment shown, second mechanism member 12 includes recess 14. As can be seen in FIG. 6 , section 11′ of first mechanism member 11 protrudes into recess 14 when second mechanism member 12 is in the inactivated position. Thus, second mechanism member 12 is movable to a position where section 11′ of first mechanism member 11 protrudes into recess 14. According to the embodiment shown, first mechanism member 11 is spherical. According to further embodiments, first mechanism member 11 may have a different form or shape, such as curved, elliptical, etc.

[0055] Furthermore, according to the embodiment shown, the mechanism 7 includes a resilient member 17 that biases the first mechanism member 11 in the direction d2 toward the second mechanism member 12. In this manner, abutting contact between the first mechanism member 11 and the second mechanism member 12 can be ensured regardless of the pivotal position of the second mechanism member 12 relative to the switch assembly 10'. The resilient member 17 may include a spring, such as a coil spring. Alternatively, the resilient member 17 may include another type of resilient element.

[0056] 6, the second mechanical member 12 includes an abutment surface 15 adjacent to the recess 14. According to the embodiment shown, the abutment surface 15 surrounds the recess 14. The second mechanical member 12 is configured to move the first mechanical member 11 in a direction d1 toward the switch 10 through abutment contact between the abutment surface 15 and the first mechanical member 11. In other words, the first mechanical member 11 is configured to move relative to the switch 10 when the second mechanical member 12 moves.

[0057] 7 shows a cross-section of the switch assembly 10' shown in FIG. 6 with the second mechanism member 12 pivoted to the actuated position. As seen in FIG. 7, the first mechanism member 11 moves in a direction d1 toward the switch 10 due to abutting contact between the abutment surfaces 15 of the first mechanism member 11 and the second mechanism member 12 as the second mechanism member 12 pivots to the actuated position. Additionally, as seen in FIG. 7, according to the illustrated embodiment, the section 11' of the first mechanism member 11 moves out of the recess 14 as the second mechanism member 12 pivots to the actuated position.

[0058] First mechanical member 11 is configured to actuate switch 10 by pressing against switch 10 when displaced in direction d1 toward switch 10. Switch 10 may be a mechanically actuated microswitch that closes an electrical circuit when actuated by the pressing force of first mechanical member 11 and breaks the electrical circuit when the pressing force is removed. In this manner, switch 10 can be actuated in a simple, reliable, and efficient manner. Furthermore, these features of mechanism 7 enable the use of mechanically actuated microswitches that are fail-safe, compact, and available at low cost.

[0059] As will be understood from the description herein, mechanism 7 is configured to move first mechanism member 11 relative to switch 10 upon pivotal movement of second mechanism member 12. According to the illustrated embodiment, abutment surface 15 is bowl-shaped and has a radius of curvature approximately equal to the distance between abutment surface 15 and the point where first and second pivot axes ax1, ax2 intersect with one another. In other words, according to the illustrated embodiment, mechanism 7 is configured so that the distances from the point where first and second pivot axes ax1, ax2 intersect with one another to different portions of abutment surface 15 are approximately equal across abutment surface 15. These features thereby provide early actuation of the switch while allowing movement of second mechanism member 12 past the trigger point, i.e., the point where second mechanism member 12 triggers actuation of switch 10. This provides a more user-friendly power tool. Furthermore, the features of mechanism 7 provide a switch assembly 10′ that is well-suited for efficient operation in various types of power tools, as will be described further herein.

[0060] 6 , when the second mechanism member 12 is pivoted to the inactivated position, the first mechanism member 11 moves in a direction d2 away from the switch 10 due to the biasing force of the elastic member 17 such that the section 11′ of the first mechanism member 11 protrudes into the opening 14 of the second mechanism member 12. This causes the switch 10 to be deactivated when the first mechanism member 11 moves in the direction d2 away from the switch 10. In this manner, the switch 10 is deactivated in a simple, reliable, and efficient manner. As will be understood from what is described herein, according to the embodiment shown, the direction d2 away from the switch 10 is, in this context, the same direction as the direction d2 toward the second mechanism member 12.

[0061] FIG. 8 shows a cross-sectional view of the elongated handle 20 of the power tool 1 according to the embodiment shown in FIGS. 1-4. In FIG. 8, one housing portion of the elongated handle 20 has been removed for visibility. As can be seen in FIG. 8, the trigger element 30 is a continuous, one-piece body, i.e., made from a single, continuous piece of material. The trigger element 30 may be made, for example, from a polymer material. These features provide the trigger element 30 with the conditions and properties that make it suitable for being manufactured and assembled in a durable yet cost-effective manner.

[0062] As described above, the trigger element 30 has an actuation portion 31 that protrudes from the grip portion 21 of the elongated handle 20. The grip portion 21 of the elongated handle 20 is bent to surround region A. The actuation portion 31 protrudes from a slot 22 that extends over the grip portion 21 of the elongated handle 20. The actuation portion 31 faces region A, and the trigger element 30 is movably disposed in the slot 22. The slot 22 is oriented inward toward region A surrounded by the elongated handle 20. The trigger element 30 is disposed within the elongated handle 20. The shape of the trigger element 30 may be designed to correspond to the shape of the elongated handle 20. The actuation portion 31 of the trigger element 30 extends through the slot 22 in the elongated handle 20 into region A. When a person grasps the grip portion 21 of the elongated handle 20, the actuation portion 31 is simultaneously grasped. The trigger element 30 is movable within the elongate handle 20, such that the trigger element 30 may move within the elongate handle 20 when the actuation portion 31 is gripped.

[0063] In FIG. 3 , the trigger element 30 is shown in an inactivated position. According to the illustrated embodiment, the inactivated position may also be referred to as a center position, since the trigger element 30 is aligned with the axis of symmetry of the elongated handle 20 when in the inactivated position. As described further herein, the chigger element 30 is configured to assume the inactivated position when not subjected to an external force, such as the gripping force of a user's hand. According to the illustrated embodiment, the power tool 1 includes a resilient member 38 configured to bias the chigger element 30 toward the inactivated position. The features and function of the resilient member 38 are further described with reference to FIG. 9 below.

[0064] As shown in FIG. 8 , the grip portion 21 of the elongated handle 20 is bent to surround region A, allowing a user to grip various portions p0, p1, and p2 of the grip portion 21 of the elongated handle 20. This allows the user to operate the power tool 1 in various orientations. Hereinafter, portion p0 of the grip portion 21 of the elongated handle 20 will be referred to as the central portion p0, portion p1 of the grip portion 21 of the elongated handle 20 will be referred to as the first side portion p1, and portion p2 of the grip portion 21 of the elongated handle 20 will be referred to as the second side portion p2. The central portion p0 of the grip portion 21 of the elongated handle 20 may also be referred to as the intermediate region of the grip portion 21. The first side portion p1 of the grip portion 21 of the elongated handle 20 may also be referred to as the first lateral region of the grip portion 21. The second side p2 of the grip portion 21 of the elongated handle 20 may also be referred to as a second lateral region of the grip portion 21.

[0065] FIG. 9 shows a cross-sectional view of the elongated handle 20 shown in FIG. 8 , with the trigger element 30 moved to the actuated position. In FIG. 9 , the trigger element 30 is shown in the actuated position, which corresponds to a situation in which a user is gripping the first side p1 of the grip portion 21 of the elongated handle 20. Hereinafter, unless otherwise specified, FIGS. 1 to 9 will be simultaneously referred to. As can be seen by comparing FIG. 8 and FIG. 9 , the trigger element 30 is moving in a direction toward the first side p1 in FIG. 9 . Due to the relative movement between the opening 37 of the trigger element 30 and the elongated handle 20, the trigger element 30 moves the second mechanism member 12 to a position where the first mechanism member 11 is pressed against the switch 10. Therefore, due to the relative movement between the trigger element 30 and the elongated handle 20, the switch 10 is actuated when the user is gripping portions p0, p1, and p2 of the grip portion 21 of the elongated handle 20.

[0066] As can be seen in FIGS. 8 and 9 , the power tool 1 includes interlocking guide surfaces 35, 35′, 35″, 41, 41′, 41″ for guiding the direction of movement of the trigger element 30 relative to the elongated handle 20. More specifically, according to the embodiment shown, the interlocking guide surfaces 35, 35′, 35″, 41, 41′, 41″ include a plurality of openings 41, 41′, 41″ and a plurality of guide pins 35, 35′, 35″. Each guide pin 35, 35′, 35″ protrudes into one of the openings 41, 41′, 41″. According to the embodiment shown, the elongated handle 20 includes openings 41, 41′, 41″ and the trigger element 30 includes guide pins 35, 35′, 35″. According to further embodiments, the trigger element 30 may include multiple apertures and the elongate handle 20 may include multiple guide pins that each protrude into one of the apertures in the trigger element 30 .

[0067] As can be seen in FIGS. 8 and 9 , according to the illustrated embodiment, the openings 41, 41′, 41″ are substantially triangular in shape. Due to the shape of the openings 41, 41′, 41″ according to the illustrated embodiment, the trigger element 30 receives a force in an upward direction in FIGS. 8 and 9 , i.e., toward the central portion p0 of the gripping portion 21, even when one of the first and second sides p1, p2 is gripped. Therefore, as can be understood from the above and by comparing FIGS. 8 and 9 , when the first side p1 is gripped, the trigger element 30 moves toward the first side p1 and the central portion p0 simultaneously due to the interlocking guide surfaces 35, 35′, 35″, 41, 41′, 41″.

[0068] When the central portion p0 is gripped, the abutting contact between the guide pin 35, 35', 35" and the opening 41, 41', 41" is released and the guide pin 35, 35', 35" moves into position within the respective opening 41, 41', 41". The interlocking guide surfaces 35, 35', 35", 41, 41', 41" allow the trigger element 30 to move within the elongated handle 20 in a predetermined manner upon gripping different portions p0, p1, p2 of the gripping portion 21 of the elongated handle 20. Furthermore, the interlocking guide surfaces 35, 35', 35", 41, 41', 41" limit the relative movement between the trigger element 30 and the elongated handle 20.

[0069] As described above, the power tool 1 includes a resilient member 38 configured to bias the chigger element 30 toward the inactivated position. According to the illustrated embodiment, the resilient member 38 is configured to bias the chigger element 30 in a downward direction relative to the elongated handle 20 in FIGS. 8 and 9 , i.e., away from the center p0 of the grip portion 21 of the elongated handle 20. Furthermore, due to the shape of the openings 41, 41′, 41″ in the illustrated embodiment, the trigger element 30 is subjected to a force in an upward direction in FIGS. 8 and 9 , i.e., toward the center p0 of the grip portion 21, regardless of the direction of movement of the chigger element 30 relative to the elongated handle 20 from the inactivated position. In this manner, the resilient member 38 is compressed when the chigger element 30 moves from the inactivated position relative to the elongated handle 20, regardless of the direction of movement therefrom, as can be seen by comparing FIGS. 8 and 9 . These features provide simple and precise control of the movement of the chigger element 30. According to the embodiment shown, the resilient member 38 is a torsion spring attached to the elongated handle 20. The resilient member 38 includes an arm 38' that abuts a portion of the chigger element 30.

[0070] According to further embodiments, the power tool 1 may include a blade spring configured to bias the chigger element 30 toward the inactivated position. Such a blade spring may be attached to the elongated handle 20, for example, at attachment points 39, 39' shown in FIG. 8 , and the blade spring may include a central portion that abuts the chigger element 30 to bias the chigger element 30 toward the inactivated position. Alternatively or additionally, the power tool 1 may include one or more other types of resilient elements, such as one or more coil springs, resilient elements, etc., for biasing the chigger element 30 toward the inactivated position.

[0071] Due to the features of mechanism 7 and the fact that second mechanism member 12 is pivotally disposed relative to switch assembly 10' about a first pivot axis ax1 and about a second pivot axis ax2 that is transverse to first pivot axis ax1, second mechanism member 12 is capable of 360-degree rotation. Furthermore, as best seen in FIG. 5, the function and attachment of second mechanism member 12 relative to switch assembly 10' is similar to a Cardan joint, except for the fact that a Cardan joint is typically configured to transmit torque, for example, in a power transmission.

[0072] 6 and 7, the features of mechanism 7 provide for early actuation of switch 10 as trigger element 30 moves relative to elongated handle 20. Additionally, the features of mechanism 7 allow trigger element 30 to move past the position at which switch 10 is actuated. In this manner, a more user-friendly power tool 1 can be provided that has a better feel and comfort when gripping elongated handle 20.

[0073] Furthermore, the features of mechanism 7 allow switch assembly 10' to be used with various types of power tools without further modification, or at least with minimal modification, which reduces manufacturing, development, and assembly costs of the power tools.

[0074] According to embodiments herein, the switch 10 may be set to a first state in which the power tool 1 is set to a deactivated state or a second state in which the power tool 1 is set to an activated state. The switch 10 may be a safety switch connected to the main trigger 6 such that the main trigger 6 is disabled when the switch 10 is in the first state and is enabled when the switch 10 is in the second state.

[0075] Thus, the switch 10 of the power tool 1 may be configured to place the power tool 1 in either an activated state or an inactivated state. An "activated state" means that the tool 2 attached to the power tool 1 may be set to a state in which it is moving. An "inactivated state" means that the tool 2 is not set to a state in which it is moving. Thus, when the power tool 1 is in an "activated state," the power source 4, the main trigger 6, and other parts associated with the movement of the tool are enabled. When the power tool 1 is in an "inactivated state," either the power source 4 or the main trigger 6, and other parts associated with the movement of the tool 2 are disabled.

[0076] The switch 10 may typically be set to either a first state or a second state. The switch 10 and power tool 1 are configured such that when the switch 10 is in the first state, the power tool 1 is in an unactivated state, and when the switch 10 is in the second state, the power tool 1 is in an activated state. To accomplish this, the switch 10 may be electrically or mechanically connected to all or any of the power source 4, the main trigger 6, or any other associated components of the power tool 1. Such configurations are within the knowledge of one skilled in the art and may not need to be described further herein.

[0077] According to one alternative, the switch 10 may be connected to the power source 4 such that the power source 4 is on when the switch 10 is in the second state and the power source 4 is off when the switch 10 is in the first state. According to a second alternative, the switch 10 is connected to the primary trigger 6 such that the primary trigger 6 is enabled when the switch 10 is in the second state and the primary trigger 6 is disabled (e.g., locked) when the switch 10 is in the first state. These two alternatives may be combined.

[0078] In general, the power tool 1 may be configured to be started when the gripping portion 21 of the elongated handle 20 is grasped and the main trigger 6 of the rear handle 5 is pressed. The switch 10 may be a mechanically actuated microswitch that closes an electrical circuit (i.e., the second state) when actuated by the pressing force of the first mechanical member 11, and breaks the electrical circuit (i.e., the first state) when the pressing force of the first mechanical member 11 is removed.

[0079] As used herein, references to directions or positions such as "up" or "down" or "upper" or "lower" or "upward" or "downward" are with respect to a situation in which the hand-held power tool is held parallel to the ground, e.g., horizontally, in which the middle center of the handle may be oriented orthogonally, such as vertically, away from the ground.

[0080] The above describes various exemplary embodiments, and it is understood that the present invention is defined solely by the appended independent claims. Those skilled in the art will appreciate that the exemplary embodiments may be modified and different features of the exemplary embodiments may be combined to create embodiments other than those described herein, without departing from the scope of the invention as defined by the appended independent claims.

[0081] As used herein, the terms "comprising" or "comprises" are open-ended and include one or more stated features, elements, steps, components, or functions, but do not exclude the presence or addition of one or more other features, elements, steps, components, functions, or groups thereof.

Claims

1. A handheld power tool (1), An electric tool body (3), Tool (2) and a power source (4) configured to power the tool (2); a switch (10) configured to set the power tool (1) in an activated or deactivated state; and an elongated handle (20) that is held by a person using the power tool (1); The elongated handle (20) includes a trigger element (30) consisting of only one part that extends along the entire elongated handle (20) and is movably disposed relative to the elongated handle (20), and the trigger element (30) moves relative to the handle (20) when a person grasps the handle (20); The switch (10) is disposed on the power tool body (3), The power tool (1) comprises a mechanism (7) operatively connected to the trigger element (30); The mechanism (7) comprises a first mechanism member (11) and a second mechanism member (12) connected to the first mechanism member (11); the second mechanism member (12) is connected to the trigger element (30); The second mechanism member (12) is configured to pivotally move about a first pivot axis (ax1) when the handle (20) is gripped; the second mechanical member (12) has a recess (14), and the second mechanical member (12) is movable to a position where a section (11') of the first mechanical member (11) protrudes into the recess (14); the second mechanism member (12) has an abutment surface (15) adjacent to the recess (14); The second mechanical member (12) is configured to move the first mechanical member (11) in a direction (d1) toward the switch (10) by abutment contact between the abutment surface (15) and the first mechanical member (11) when the section (11') of the first mechanical member (11) moves out of the recess (14) during pivotal movement of the second mechanical member (12).

2. The power tool (1) according to claim 1, wherein the second mechanism member (12) is arranged to be pivotable about a second pivot axis (ax2) that intersects the first pivot axis (ax1).

3. The power tool (1) according to claim 1 or 2, wherein the trigger element (30) comprises an opening (37), and the second mechanism member (12) comprises a knob (16) that protrudes into the opening (37).

4. 2. The power tool (1) according to claim 1, wherein the abutment surface (15) is curved, bowl-shaped, or both.

5. The power tool (1) according to claim 1 or 2, further comprising an elastic member (17) that biases the first mechanical member (11) in a direction (d2) toward the second mechanical member (12).

6. The power tool (1) according to claim 1 or 2, wherein the first mechanical member (11) is spherical or elliptical.

7. The power tool (1) according to claim 1 or 2, wherein the mechanism (7) is arranged on the power tool body (3).

8. The power tool (1) according to claim 1 or 2, wherein the elongated handle (20) has a grip portion (21) that is gripped by a person, and the trigger element (30) has an actuation portion (31) that protrudes from the grip portion (21) of the elongated handle (20).

9. 9. The power tool (1) of claim 8, wherein the grip portion (21) of the elongated handle (20) is bent to at least partially surround the area (A), and the actuation portion (31) protrudes from a slot (22) extending on the grip portion (21) of the elongated handle (20) and faces the area (A).

10. 3. The power tool (1) according to claim 1 or 2, wherein the power tool (1) comprises interlocking guide surfaces (35, 35', 35'', 41, 41', 41'') for guiding the direction of movement of the trigger element (30) relative to the handle (20).

11. 11. The power tool (1) according to claim 10, wherein the interfitting guide surfaces (35, 35', 35'', 41, 41', 41'') comprise an opening (41, 41', 41'') and a guide pin (35, 35', 35'') protruding into the opening (41, 41', 41'').

12. The power tool (1) according to claim 1 or 2, wherein the power tool (1) is a hedge trimmer, a string trimmer or a brush cutter.

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