High efficiency mower blade

Abstract

A cutting blade (100) for a mower can include a mounting portion (130) and a plurality of cutting elements (102, 104, 106, 108). The mounting portion (130) can include a plurality of mounting arms (136) and a mounting hole (132) formed at an axis of the cutting blade. The mounting hole (132) can be configured to interface with a shaft of the mower. Each of the cutting elements (102, 104, 106, 108) is operably coupled to a corresponding one of the mounting arms (136). Each of the cutting elements can include a wing portion (110) at a distal end thereof and a transition region (120) configured to operably couple the wing portion (110) to a respective one of the mounting arms (136). The cutting element can also include a first cutting edge (140) disposed at the wing portion (110) and a second cutting edge (142) disposed at the transition region (120).

Description

Technical Field

[0001] The exemplary embodiments generally relate to a lawnmower blade, and more specifically, to a lawnmower blade designed to provide good performance while reducing power consumption. Background Technology

[0002] Lawn care tasks are typically performed using a variety of tools and / or machines, each constructed to perform a specific task. Some tasks, such as mowing, are usually done by lawnmowers. Lawnmowers can come in many different sizes and vary considerably in design and performance. However, in addition to changes in design, size, and functionality, users have recently gained more choices regarding the power source of lawnmowers. While diesel or gasoline engines have dominated the market for decades, the market for battery-powered lawnmowers is emerging.

[0003] Unlike diesel or gasoline engines, which can be quickly refueled almost anywhere on the job site, battery-powered equipment requires a period of downtime to recharge (unless a new, pre-charged battery is available to replace a depleted one). However, for large jobs, if there isn't enough time to recharge a depleted battery, and the replacement battery or multiple batteries themselves are depleted during operation, even battery replacement may not be sufficient to complete the job. In other words, if the charging rate of a depleted battery cannot keep up with the rate at which the battery in use is draining, then even if a battery is replaced, at least some time must be spent waiting for it to recharge before the work can be completed. Due to the potential limitations of battery charging, it becomes increasingly important that battery-powered equipment has sufficient capacity to complete the work on-site after a single charge (or at least without waiting for any recharging time before completion), thus ensuring the viability and growth of this emerging market.

[0004] To achieve these expectations, improving the efficiency of lawnmowers may be helpful. Furthermore, since the rotation of the lawnmower blades is one of the main sources of power consumption in battery-powered lawnmowers, improving the efficiency of the lawnmower blades themselves could significantly increase the achievable operating time of a given battery-powered lawnmower. Summary of the Invention

[0005] Some exemplary embodiments may provide a cutting blade for a lawnmower. The cutting blade may include a mounting portion and a plurality of cutting elements. The mounting portion may include a plurality of mounting arms and a mounting hole formed at the axis of the cutting blade. The mounting hole may be configured to intersect with the axis of the lawnmower. Each of the cutting elements is operatively coupled to a corresponding one of the mounting arms. Each of the cutting elements may include a wing at its distal end and a transition region configured to operatively couple the wing to a corresponding one of the mounting arms. The cutting element may also include a first cutting edge disposed at the wing and a second cutting edge disposed at the transition region. Attached Figure Description

[0006] Having thus given a general description of the invention, please now refer to the accompanying drawings, which are not necessarily drawn to scale, wherein:

[0007] Figure 1 A top perspective view of a high-efficiency blade according to an exemplary embodiment is shown;

[0008] Figure 2 An exemplary embodiment is shown. Figure 1 Side view of a medium- to high-efficiency blade;

[0009] Figure 3 A top view of a high-efficiency blade according to an exemplary embodiment is shown;

[0010] Figure 4 A bottom view of a high-efficiency blade according to an exemplary embodiment is shown;

[0011] Figure 5 A perspective view of the wing and transition region of a single cutting element of a separate high-efficiency blade, according to an exemplary embodiment, is shown;

[0012] Figure 6 This is according to an exemplary embodiment. Figure 5 Top perspective view of the wing and transition area 120 of a single cut element;

[0013] Figure 7 This is a perspective view of a single cut element as observed from a point in front of the wing, according to an exemplary embodiment;

[0014] Figure 8 This is a perspective view of the wing and transition region as observed from a point displaced at the distal end of the wing, according to an exemplary embodiment.

[0015] Figure 9 An example of an embodiment of the process is shown. Figure 3 A cross-sectional view of the wing section taken by line A-A'; and

[0016] Figure 10An example of an embodiment of the process is shown. Figure 3 The cross-sectional view taken by line B-B'. Detailed Implementation

[0017] Some exemplary embodiments will be described more fully below with reference to the accompanying drawings, which illustrate some, but not all, exemplary embodiments. In fact, the examples described and illustrated herein should not be construed as limiting the scope, applicability, or configuration of this disclosure. Rather, these exemplary embodiments are provided to adapt this disclosure to meet legal requirements. The same reference numerals always refer to the same elements. Furthermore, as used herein, the term “OR” is interpreted as a logical operator whose result is true when one or more of its operands are true. As used herein, operative coupling should be understood to involve direct or indirect connections that enable functional interconnection of components operatively coupled to each other.

[0018] Some exemplary embodiments can provide lawnmower blades with design features and geometries that define a structure capable of delivering high performance with less power consumption. In this regard, for example, the high-efficiency blade described herein comprises multiple (e.g., four) blade elements, each including two cutting edges. These cutting edges are configured with a sweeping structure having a lift geometry that increases lift by more than 50% (in some cases up to 63% or more) and reduces drag by at least 40% compared to conventional blade designs. Therefore, the structure provided herein enables an efficient and superior cutting experience.

[0019] The following will refer to Figures 1 to 10 An exemplary embodiment will be described. Figure 1 A top perspective view of a high-efficiency blade 100 according to an exemplary embodiment is shown. Figure 2 A side view of the high-efficiency blade 100 is shown. Figure 3 and Figure 4 The top and bottom views of the high-efficiency blade 100 are shown respectively. Figure 5 A perspective view of the wing 110 and transition region 120 of a single cutting element of the high-efficiency blade 100 is shown (cut from a perspective view at the blade axis of the high-efficiency blade 100). Figure 6 yes Figure 5 Top perspective view of the wing 110 and transition region 120 of a single cut element. Meanwhile, Figure 7 This is a perspective view of a single cut element as seen from a point in front of wing 110, and Figure 8 This is a perspective view taken from a point where the wing 110 has been displaced at its distal end. Figure 9 It shows along Figure 3 A cross-sectional view of wing 110 taken along line A-A', and Figure 10 It shows along Figure 3The cross-sectional view taken by line B-B'.

[0020] Now for reference Figures 1 to 8 The high-efficiency blade 100 may include multiple cutting elements (e.g., a first cutting element 102, a second cutting element 104, a third cutting element 106, and a fourth cutting element 108). These cutting elements are configured to define a balanced and symmetrical structure to improve the ease with which the high-efficiency blade 100 rotates about a shaft driven by the lawnmower's engine. The high-efficiency blade 100 also includes a mounting portion 130 to which each cutting element is attached. The mounting portion 130 may include a mounting hole 132 located at its center. The mounting hole 132 may have any shape required for engagement with the lawnmower's shaft. Thus, for example, the mounting hole 132 may have a circular shape (as shown) or other shapes, such as star-shaped, rectangular, triangular, or many other geometries. The mounting portion 130 may engage with the lawnmower's shaft directly or indirectly (e.g., through a mounting structure operatively coupled to the shaft). In any case, the mounting portion 130 (particularly the mounting hole 132) may define a rotation axis 134 of the high-efficiency blade 100.

[0021] The mounting portion 130 may also include corresponding examples of mounting arms 136 for each of the first cutting element 102, the second cutting element 104, the third cutting element 106, and the fourth cutting element 108. The mounting arms 136 may have a significantly smaller desired width than the wing portion 110, thereby minimizing the weight of the mounting portion 130. By maintaining the low weight of the mounting portion 130 and by providing good aerodynamic characteristics for the wing portion 110, the lift provided by the high-efficiency blade 100 can be increased and the power required to rotate the high-efficiency blade 100 can be reduced. Furthermore, by employing a balanced configuration with four equally spaced cutting elements, corresponding cutting edges, and lift surfaces, the efficiency of the high-efficiency blade 100 can be increased by more than 20% compared to a more conventional two-cutting-edge design.

[0022] Each of the cutting elements may include a first cutting blade 140 and a second cutting blade 142. The first cutting blade 140 may extend through the leading edge of the wing 110, and the second cutting blade 142 may extend through the leading edge of the transition region 120. In an exemplary embodiment, the first cutting blade 140 may extend completely through the leading edge of the wing 110, and the second cutting blade 142 may extend completely through the leading edge of the transition region 120. However, the first cutting blade 140 and the second cutting blade 142 may be configured to extend only a portion (not all) of the leading edges of the wing 110 and the transition region, respectively. In the context of this disclosure, the leading edge should be understood as the direction of rotation indicated by reference to arrow 144 (i.e., clockwise when viewed from above).

[0023] The wing 110 may be a sheet material (e.g., a fin or wing) shaped to extend from the proximal end 200 of the wing 110 (see...). Figure 8 and 9 The wing portion 110 has a substantially uniform shape to its distal end 202. The proximal end 200 of the wing portion 110 may be attached to the distal end 204 of the transition region 120. The proximal end 206 of the transition region 120 may be attached to the mounting portion 130. In an exemplary embodiment, the first cutting edge 140 of each of the cutting elements may be in the same plane (e.g., the cutting plane 210) such that the rotation of the high-efficiency blade 100 carrying the first cutting edges 140 of all the cutting elements passes uniformly through the cutting plane 210 (see...). Figure 2 ).like Figure 8 As shown, the wing 110 can be formed to curve from the first cutting edge 140 to the trailing edge 220 of the wing 110 (on a substantially consistent arc).

[0024] In an exemplary embodiment, the trailing edge 220 of each of the wings 110 of the cutting element may also be located in the same plane spaced apart from the cutting plane 210 (e.g., Figure 2 (See trailing edge plane 230 shown). Meanwhile, the trailing edge 220 and the first cutting blade 140 of each of the cutting elements can extend substantially parallel to each other from the proximal end 200 to the distal end 202 of the wing 110. The trailing edge 220 can also be chamfered compared to a similar design without chamfering features to further increase the efficiency of the high-efficiency blade 100 by approximately 2%. In some embodiments, the mounting portion 130 (and therefore the mounting arm 136) can be located in a plane within approximately the middle path between the cutting plane 210 and the trailing edge plane 230 (or within approximately 40% to 60% of the path between the cutting plane 210 and the trailing edge plane 230).

[0025] The chord length of the wing 110 is chosen to be approximately 4.6 inches. This chord length can improve efficiency by approximately 3% due to the aerodynamic characteristics of the resulting wing. Figure 9 As shown, for a chord length of approximately 4.6 inches at wing 110, the angular difference (i.e., wing angle of attack) measured between the cutting plane 210 and the straight line directly from the first cutting edge 140 to the trailing edge 220 is approximately 17 degrees. However, in various exemplary embodiments, any value ranging from approximately 10 degrees to 30 degrees can be used. Wing angles of attack within this range offer good lift and efficiency improvements. Furthermore, the efficiency is improved by approximately 17% when the wing angle of attack is 17 degrees compared to a design without a wing angle of attack.

[0026] like Figures 1 to 8As shown, relative to the transition region 120, the wing 110 (and the corresponding portion of the mounting portion 130, which is operatively coupled to a corresponding one of the transition regions 120 of the cutting element) is in a swept configuration. Specifically, as... Figure 3 As shown, the angular difference between the straight line 250 extending along the first cutting edge 140 and the radial line 255 extending from the axis 134 at the mounting hole 132 to the blade tip (i.e., the intersection between the distal end 202 of the wing 110 and the first cutting edge 140) is approximately 30 degrees. This angular difference defines the swept angle 260, or the angle at which the first cutting edge 140 sweeps (forward in this example) relative to the mounting arm 136.

[0027] In an exemplary embodiment, the width of the mounting arm 136 (e.g.) Figure 10 The width of the mounting arm 136 (as shown) can be approximately 43% of the chord length of the wing 110. Therefore, in this example, since the chord length is 4.6 inches, the width of the mounting arm 136 can be approximately 2 inches. The transition region 120 can be configured to provide a transition from the mounting arm 136 to the wing 110 (both in the form of accommodating the sweep angle 260), a transition from the narrower (e.g., 2-inch) mounting arm 136 to the wider (e.g., 4.6-inch chord length) wing 110, and a transition from the flat mounting arm 136 to the curved wing 110. Therefore, the transition region 120 can be configured to both widen and twist, while also curving from the proximal end 206 to the distal end 204 of the transition region 120. In this respect, for example, the transition region 120 bends forward by approximately 30 degrees (e.g., to the right when viewed from above, but generally towards the leading edge of the wing 110) to provide the sweep angle 260. Because the mounting arm 136 is flat and located between the trailing edge plane 230 and the cutting plane 210, the transition region 120 is also twisted, causing the tail (or rear end) of the transition region 120 to rise from the tail or rear end of the mounting arm 136 to contact the trailing edge 220 of the wing. Simultaneously, the front or leading edge of the transition region 120 falls from the front or rear end of the mounting arm 136 to contact the first cutting edge 140. The second cutting edge 142 follows this transition and therefore includes a curve extending upward away from the cutting plane 210 while curving at an angle in a direction away from the trailing edge 220 of the wing 110. The second cutting edge 142 extends upward and away from the cutting plane 210, allowing it to combine with the significant lift provided by the wing 110 to function as a cover blade.

[0028] In some exemplary embodiments, an aerodynamic aperture 300 may be provided in the transition region 120 to further improve efficiency. The aerodynamic aperture 300 may be located approximately at the midpoint between the distal end 204 and the proximal end 206 of the transition region 120. In some cases, the aerodynamic aperture 300 may be circular, rectangular, or other geometrically shaped. However, compared to the same design without an aerodynamic aperture 300, employing a square-shaped (e.g., with rounded corners) aerodynamic aperture at the midpoint of the transition region 120 can increase the efficiency of the high-efficiency blade 100 by approximately 11%.

[0029] The high-efficiency blade 100 of the exemplary embodiment employs a combination of various efficiency-enhancing features to maximize efficiency. However, it should also be understood that multiple combinations of subsets of the above features can also be used to improve efficiency, without the need to combine all the features. The combination of all the above features has been shown to provide up to 63% more lift per pound of drag and reduce drag by 40% compared to the comparable lift provided by currently available standard lawnmower blades.

[0030] Therefore, some exemplary embodiments may include a cutting blade for a lawnmower. The cutting blade may include a mounting portion and a plurality of cutting elements. The mounting portion may include a plurality of mounting arms and a mounting hole formed at the axis of the cutting blade. The mounting hole may be configured to intersect with the axis of the lawnmower. Each of the cutting elements may be operatively coupled to a corresponding one of the mounting arms. Each of the cutting elements may include a wing located at its distal end and a transition region configured to operatively couple the wing to a corresponding one of the mounting arms. The cutting element may also include a first cutting edge disposed at the wing and a second cutting edge disposed at the transition region.

[0031] In exemplary embodiments, the cutting blade may include additional, optional features, and / or may modify or extend the aforementioned features. Examples of some modifications, optional features, and extensions are described below. It should be understood that modifications, optional features, and extensions may be added individually, or they may be added cumulatively in any desired combination. In exemplary embodiments, the first cutting edge of each of the cutting elements may extend linearly from the proximal end of the wing through the leading edge of the wing to the distal end of the wing, and the first cutting edge of each of the cutting elements may be located in the cutting plane. In exemplary embodiments, the wing may further include a trailing edge disposed opposite to and substantially parallel to the first cutting edge extending on the wing, and the trailing edge of each of the cutting elements may be located in the trailing edge plane. In some cases, the mounting portion may be located in a plane covering approximately half the path between the trailing edge plane and the cutting plane. In exemplary embodiments, the trailing edge may be chamfered. In some cases, a second cutting edge may extend from the proximal end of the transition region through the leading edge of the transition region to the distal end of the transition region. In an exemplary embodiment, the second cutting edge and the first cutting edge can form a continuous cutting surface, and the second cutting edge can extend away from the cutting plane as it moves from the distal end of the transition region toward the proximal end of the transition region. In some cases, the second cutting edge bends away from the trailing edge as it moves from the distal end of the transition region toward the proximal end of the transition region. In an exemplary embodiment, the chord length of the wing from the first cutting edge to the trailing edge can exceed twice the width of the mounting arm. In some cases, the transition region can be configured such that the width of the transition region from the leading edge to the trailing edge gradually decreases from the chord length of the wing at the distal end of the transition region to the width of the mounting arm at the proximal end of the transition region. In an exemplary embodiment, the transition region can include an aerodynamic aperture disposed on a portion thereof. In some cases, the aerodynamic aperture can be square in shape with rounded corners. In an exemplary embodiment, the aerodynamic aperture is disposed at the center of the transition region. In some cases, the electronic connection assembly can include a wired connection between the electrical system of the host device and the motor. In an exemplary embodiment, the wing can be configured to bend from the first cutting edge toward the trailing edge, thereby limiting the angle of attack to approximately between 15 degrees and 20 degrees. In some cases, the wing can sweep relative to the mounting arm at a sweep angle between approximately 20 and 40 degrees. In an exemplary embodiment, this sweep angle is approximately 30 degrees. In some cases, the cutting blade may include four cutting elements equidistant from each other. In an exemplary embodiment, the wing may be curved, and the mounting portion is flat. A transition region is flat at its proximal end and curved at its distal end to transition from the mounting portion to the wing. In some cases, the distal end of the transition region may include a first portion extending downward from the plane of the mounting portion to the first cutting edge, and a second portion extending upward from the plane to the trailing edge of the wing.

[0032] Benefiting from the teachings presented in the foregoing description and related drawings, those skilled in the art will conceive of many modifications and other embodiments of the invention set forth herein. Therefore, it should be understood that the invention is not limited to the specific embodiments disclosed, and that modifications and other embodiments are intended to be included within the scope of the appended claims. Furthermore, while the foregoing description and related drawings describe exemplary embodiments in the context of certain exemplary combinations of elements and / or functions, it should be understood that different combinations of elements and / or functions may be provided by alternative embodiments without departing from the scope of the appended claims. In this regard, for example, combinations of elements and / or functions different from those explicitly described above are also contemplated as being set forth in some of the appended claims. If advantages, benefits, or solutions to problems are described herein, it should be understood that such advantages, benefits, and / or solutions may apply to some exemplary embodiments but not necessarily to all exemplary embodiments. Therefore, any advantages, benefits, or solutions described herein should not be considered critical, necessary, or indispensable to all embodiments or the embodiments claimed herein. Although specific terms are used herein, they are used in a general and descriptive sense only and are not intended to be limiting.

Claims

1. A cutting blade for a lawnmower, the cutting blade comprising: The mounting section includes a plurality of mounting arms and a mounting hole formed at the axis of the cutting blade, the mounting hole being configured to intersect with the axis of the lawnmower; as well as Multiple cutting elements, each of which is operatively coupled to a corresponding one in the mounting arm. Each of the cutting elements includes: a wing located at a distal end of the cutting element; and a transition region configured to operatively couple the wing to a corresponding one of the mounting arms. The cutting element further includes a first cutting blade disposed at the wing and a second cutting blade disposed at the transition region. In each of the cutting elements, the first cutting edge extends linearly from the proximal end of the wing through the leading edge of the wing to the distal end of the wing, and the first cutting edge of each of the cutting elements is located within the cutting plane. The wing also includes a trailing edge, which is disposed opposite to and extends substantially parallel to the first cutting edge on the wing. The trailing edge of each of the cutting elements lies within a trailing edge plane. Wherein, the second cutting edge extends from the proximal end of the transition region through the leading edge of the transition region to the distal end of the transition region, and The second cutting edge and the first cutting edge form a continuous cutting surface. When the second cutting edge moves from the distal end of the transition region toward the proximal end of the transition region, the second cutting edge extends away from the cutting plane.

2. The cutting blade according to claim 1, wherein, The mounting portion is located in a plane approximately halfway between the trailing edge plane and the cutting plane.

3. The cutting blade according to claim 1, wherein, The trailing edge is chamfered.

4. The cutting blade according to claim 1, wherein, As the second cutting edge moves from the distal end of the transition region toward the proximal end of the transition region, the second cutting edge bends away from the trailing edge.

5. The cutting blade according to claim 1, wherein, The chord length of the wing from the first cutting edge to the trailing edge is more than twice the width of the mounting arm.

6. The cutting blade according to claim 5, wherein, The transition region is configured such that the width of the transition region from its leading edge to its trailing edge gradually decreases from the chord length of the wing at the far end of the transition region to the width of the mounting arm at the near end of the transition region.

7. The cutting blade according to claim 6, wherein, The transition region includes an aerodynamic hole located in a portion of the transition region.

8. The cutting blade according to claim 7, wherein, The aerodynamic port is square in shape with rounded corners.

9. The cutting blade according to claim 8, wherein, The aerodynamic hole is located at the center of the transition region.

10. The cutting blade according to claim 8, wherein, Electronic connection components include wired connections between the electrical system of the host device and the motor.

11. The cutting blade according to claim 1, wherein, The wing is configured to curve from the first cutting edge toward the trailing edge, thereby limiting the angle of attack to between 15 and 20 degrees.

12. The cutting blade according to claim 1, wherein, The wing sweeps relative to the mounting arm at a sweep angle between 20 and 40 degrees.

13. The cutting blade according to claim 12, wherein, The sweep angle is approximately 30 degrees.

14. The cutting blade according to claim 1, wherein, The cutting blade comprises four cutting elements spaced equidistant from each other.

15. The cutting blade according to claim 1, wherein, The wing is curved and the mounting portion is flat, and The transition region is flat at its proximal end and curved at its distal end to transition from the mounting portion to the wing portion.

16. The cutting blade according to claim 15, wherein, The distal end of the transition region includes: a first portion extending downward from the plane where the mounting portion is located to the first cutting edge; and a second portion extending upward from the plane to the trailing edge of the wing.

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