Cutting assembly

Abstract

A cutting assembly 20 for a hair cutting device 10 includes a plurality of guard teeth 28 and a guard blade 22 that defines an x-axis 50 passing through the tips of the guard teeth, with the plurality of guard teeth arranged along an upper edge of the guard blade. A cutting blade 24 is configured to cooperate with the guard blade to cut hair. The cutting blade includes a plurality of cutting teeth 30 that extend along a cutting edge of the cutting blade and define a cutting axis 150 passing through the tips of the cutting teeth. The guard blade is assembled adjacent to the cutting blade such that the guard blade and the cutting blade are configured to slide relative to each other within a blade plane while maintaining contact with each other. The guard teeth and the cutting teeth overlap, the cutting axis is parallel to the x-axis, and the cutting blade is configured to reciprocate along the cutting axis relative to the guard blade. As a result, the cutting teeth and the guard teeth cooperate to cut hair. The cutting assembly further includes an adjustment mechanism 26 having an input device configured to be operated by a user. The adjustment mechanism is configured to be switched between a neutral configuration and a y-set configuration. In the y-set configuration, the input device of the adjustment mechanism is engaged with a y-gear mechanism such that operation of the input device forces movement of the y-gear mechanism, which moves the cutting blade along a y-axis 250 within the blade plane and perpendicular to the x-axis relative to the guard blade to align the cutting axis with the x-axis in the blade plane. In the neutral configuration, the input device is disengaged from the y-gear mechanism such that the input device can be freely operated without moving the cutting blade along the y-axis relative to the guard blade.

Description

Technical Field

[0001] The present disclosure relates to a cutting assembly for a hair cutting device and a hair cutting device.

Background Art

[0002] Hair cutting devices typically include a guard blade and a cutting blade, which must be perfectly aligned for optimal hair cutting performance.

Summary of the Invention

Problems to be Solved by the Invention

[0003] However, manufacturing tolerances of the cutting blade and tolerances in manual replacement can result in misalignment between the cutting blade and the guard blade.

Means for Solving the Problems

[0004] According to a first specific aspect, a cutting assembly for a hair cutting device is provided, the cutting assembly comprising: a guard blade including a plurality of guard teeth, the guard blade defining an x-axis passing through the tips of the plurality of guard teeth, the plurality of guard teeth being arranged along an upper edge of the guard blade; and a cutting blade configured to cooperate with the guard blade to cut hair, the cutting blade including a plurality of cutting teeth, the plurality of cutting teeth extending along a cutting edge of the cutting blade, the cutting blade defining a cutting axis passing through the tips of the plurality of cutting teeth; the guard blade is assembled adjacent to the cutting blade, such that the guard blade and the cutting blade are configured to slide relative to each other within a blade plane while maintaining contact with each other, the guard teeth and the cutting teeth overlap, and the cutting axis is parallel to the x-axis, the cutting blade is configured to reciprocate along the cutting axis relative to the guard blade, such that the cutting teeth and the guard teeth cooperate to cut hair. The cutting assembly further has an adjustment mechanism including an input device configured to be operated by a user, and the adjustment mechanism is configured to be switchable between a neutral configuration and a y-set configuration, In the y-set configuration, the input device of the adjustment mechanism is engaged with the y-gear mechanism, and as a result, the operation of the input device forces the movement of the y-gear mechanism, which moves the cutting blade along the y-axis perpendicular to the x-axis in the blade plane with respect to the guard blade in order to align the cutting axis with the x-axis in the blade plane, In the neutral configuration, the input device is disengaged from the y-gear mechanism, and as a result, the input device can be freely operated without causing the movement of the cutting blade along the y-axis with respect to the guard blade.

[0005] The input device of the adjustment mechanism can have an elongated rod extending along the rod axis and a wheel at the axial end of the rod. The input device is movable along the rod axis with respect to the y-gear mechanism to engage and disengage from the y-gear mechanism, and thereby can be configured to switch the adjustment mechanism between the y-set configuration and the neutral configuration respectively.

[0006] The y-gear mechanism can have a first worm gear and a second worm gear spaced apart along a direction parallel to the x-axis and fixed by a base, and the base is coupled to the cutting blade. The first worm gear and the second worm gear can each have a first helical worm meshed with a first worm wheel and a second helical worm meshed with a second worm wheel. As a result, when simultaneously engaged by the input device in the y-set configuration, the first worm gear and the second worm gear are configured to move the cutting blade along the y-axis with respect to the guard blade.

[0007] Simultaneously engaging the two worm gears spaced apart along a direction parallel to the x-axis in the y-set configuration means that the two sides of the cutting blade can be moved simultaneously, reducing the possibility of accidental angular movement of the cutting blade with respect to the guard blade without the need for a guide.

[0008] The rod can have a first y-key and a second y-key spaced along the rod axis by the same amount as the first worm gear and the second worm gear. The rod can pass through the first helical worm and the second helical worm. In the y-set configuration, the first y-key is configured to engage the first helical worm, and the second y-key can be configured to engage the second helical worm, such that rotation of the wheel of the input device forces rotation of the first helical worm and the second helical worm. This forces corresponding rotation of the first and second worm wheels, whereby the cutting blade is moved along the y-axis relative to the guard blade. In the neutral configuration, the first y-key and the second y-key are configured to disengage from the first and second helical worms, such that rotation of the wheel of the input device does not move the cutting blade relative to the guard blade.

[0009] The guard blade can have a plurality of rod holders, the plurality of rod holders having openings through which the rod is passed and along which the rod is movable along the rod axis, the openings in the rod holders being elliptical to allow movement of the rod along the y-axis.

[0010] A bias element can be disposed between the guard blade and the base, which biases the guard blade away from the base, such that the cutting axis is biased away from the x-axis in the direction towards the guard blade. As a result, the cutting teeth do not project beyond the guard teeth. This is important for ensuring the safety of the mechanism. The teeth of the cutting blade are typically much sharper than the teeth of the guard blade, and thus biasing the cutting blade to prevent projection of the cutting teeth improves user safety.

[0011] The first worm wheel and the second worm wheel have eccentric protrusions, which engage with individual battless on the guard blade and are configured to apply a force from the base to the guard blade that counteracts the force applied to the guard plate by the biasing element, and by operating the input device, fine adjustment of the position of the cutting axis along the y-axis with respect to the guard blade is enabled.

[0012] The adjustment mechanism can further be configured to be switched to an x-set configuration, in which the input device is disengaged from the y-gear mechanism and engages with an x-gear mechanism configured to move the cutting blade along the cutting axis, and as a result, the operation of the input device forces the movement of the x-gear mechanism, which moves the cutting blade along the cutting axis with respect to the guard blade.

[0013] The input device can be configured such that movement along the rod axis of the input device switches the adjustment mechanism between the y-set configuration, the x-set configuration, and the neutral configuration.

[0014] The x-gear mechanism can have a third helical worm disposed between the first worm gear and the second worm gear and configured to engage with a base gear on the base, and as a result, when the third helical worm is rotated by the input device, the cutting blade is moved along the cutting axis with respect to the guard blade.

[0015] The base gear can have an internal thread on the base that corresponds to the external thread of the third helical worm.

[0016] The rod can have an x key disposed between a first y key and a second y key. In a y set configuration, the x key can be configured to disengage from a third helical worm, such that operation of the input device does not move the cutting blade along the cutting axis. In an x set configuration, the x key can be configured to engage with the third helical worm, the first y key can be configured to disengage from the first helical worm of the first worm gear, and the second y key can be configured to disengage from the second helical worm of the second worm gear, such that operation of the input device forces rotation of the third helical worm, whereby the cutting blade is moved along the cutting axis relative to the guard blade and the cutting blade is not moved along the y axis relative to the guard blade. In a neutral configuration, the x key can be configured to disengage from the third helical worm, such that operation of the input device does not move the cutting blade relative to the guard blade.

[0017] The adjustment mechanism can be further configured to switch to an angle set configuration, in which the input device is disengaged from the y gear mechanism and engaged with an angle gear mechanism, such that operation of the input device forces movement of the angle gear mechanism, which moves the cutting blade to rotate about an angle axis perpendicular to both the cutting axis and the y axis.

[0018] The angle gear mechanism can have a part of the y gear mechanism.

[0019] The input device can be configured such that movement along the rod axis of the input device switches the adjustment mechanism among the y set configuration, the angle set configuration, and the neutral configuration. The input device can be configured such that movement along the rod axis of the input device switches the adjustment mechanism among the y set configuration, the angle set configuration, the x set configuration, and the neutral configuration.

[0020] The angle gear mechanism can have the first worm gear or the second worm gear.

[0021] In the angle set configuration, the angle key is configured to engage with the first helical worm or the second helical worm, the first y key is configured to disengage from the first helical worm, the second y key is configured to disengage from the second helical worm, and the x key can be configured to disengage from the third helical worm, such that the operation of the input device results in an angular rotation of the cutting blade relative to the guard blade and does not move the cutting blade along the cutting axis or the y-axis relative to the guard blade.

[0022] According to a second aspect, a hair cutting device is provided, which has a handle, a cutting assembly according to the first aspect, and a drive mechanism configured to reciprocate the cutting blade along the cutting axis relative to the guard blade.

[0023] These and other aspects will become apparent from the embodiments described below and will be described with reference to the embodiments.

Brief Description of the Drawings

[0024]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Modes for Carrying Out the Invention

[0025] The following exemplary embodiments will be described with reference to the following drawings, which are merely exemplary.

[0026] FIG. 1 shows a hair cutting device 10 having a handle 12 and a cutting assembly 20 configured to cut hair.

[0027] FIGS. 2 and 3 show an assembled view and an exploded view of the cutting assembly 20, respectively.

[0028] The cutting assembly 20 has a guard blade 22, a cutting blade 24, and an adjustment mechanism 26.

[0029] The cutting blade 24 is configured to cooperate with the guard blade 22 to cut hair. Specifically, the guard blade 22 has a plurality of guard teeth 28 arranged along the upper edge of the guard blade 22. The guard blade 22 defines an x-axis 50 passing through the tips of the guard teeth 28. The cutting blade 24 has a plurality of cutting teeth 30 extending along the cutting edge of the cutting blade 24 and defining a cutting axis 150 passing through the tips of the cutting teeth 30.

[0030] The guard blade 22 and the cutting blade 24 are substantially planar, and the guard blade 22 is assembled adjacent to the cutting blade 24 such that the cutting teeth 30 overlap the guard teeth 28, and the guard blade 22 and the cutting blade are configured to slide within a blade plane that is parallel to the respective planes of the guard blade 22 and the cutting blade 24 relative to each other. While sliding within the blade plane, the guard blade 22 and the cutting blade 24 are configured to remain in contact. In this example, the cutting axis 150 is made to be on the same straight line as the x-axis 50 in FIG. 2. In some examples, the cutting axis 150 may not be on the same straight line as the x-axis 50, but can be configured to be parallel to the x-axis 50. In other examples, the cutting axis 150 may not be parallel to the x-axis 50, but is configured to be parallel to the x-axis 50 for optimal alignment during use. Therefore, the adjustment mechanism can be configured to correct the alignment of the cutting axis 150 to be parallel to the x-axis 50.

[0031] In use, the cutting blade 24 is configured to reciprocate along the cutting axis 150 relative to the guard blade 22, such that as a result, the cutting teeth 30 and the guard teeth 28 cooperate to cut the hair. Returning to FIG. 1, the hair cutting apparatus 10 has a drive mechanism 16 configured to reciprocate the cutting blade 24 along the cutting axis 150 relative to the guard blade 22.

[0032] Returning to FIGS. 2 and 3, in this example, the cutting assembly 20 has a base 32 that is coupled to the cutting blade 24 and constrained by the guard blade 22.

[0033] The base 32 is constrained relative to the guard blade 22 along the x-axis 50 by a pair of buttresses 48 that project from the guard blade 22, each buttress 48 having an overhang. To constrain relative movement between the guard blade 22 and the base 32 in a direction perpendicular to the blade plane, the side surfaces of the base 32 have grooves provided under the overhangs of the buttresses 48. The side surfaces of the base 32 also abut the individual buttresses 48, such that the buttresses 48 prevent relative movement between the base 32 and the guard blade 22 in a direction parallel to the x-axis 50. The base 32 is movable relative to the guard blade 22 along the y-axis 250, which is perpendicular to the x-axis 50 and parallel to the blade plane. The base 32 is biased along the y-axis 250 relative to the guard blade 22 by a biasing element 52 in the form of a pair of compression springs 52 that act between a pair of stops 60 of the guard blade 22 and the base 32 to bias the base 32 away from the guard teeth 28. The counterforce along the y-axis 250 to the force applied by the biasing element 52 is provided by the base 32 abutting the buttresses 48, which, as will be explained in more detail below, provides adjustment of the base 32 along the y-axis 250 relative to the guard blade 22.

[0034] The cutting blade 24 is configured to reciprocate along a cutting axis 150 with respect to the base 32. In this example, the cutting blade 24 is constrained to move only along the cutting axis 150 with respect to the base 32, such that the cutting blade does not move along the y-axis 250 with respect to the base 32. Accordingly, when the base 32 is moved along the y-axis 250 with respect to the guard blade 22, the cutting blade 24 is also moved along the y-axis 250 with respect to the guard blade 22 by a corresponding amount. By abutting against the base 32 and being held in place by the bi-directional torsion spring element 34, the cutting blade 24 is constrained such that it cannot move with respect to the base 32 along the y-axis 250.

[0035] Accordingly, biasing the base 32 with the biasing element 52 towards the lower edge of the guard blade 22 (opposite the upper edge of the guard blade 22 where the guard teeth 28 are disposed) biases the cutting blade 24 towards the lower edge of the guard blade 22 as well. This biases the cutting axis 150 away from the x-axis 50 in a direction towards the lower edge of the guard blade 22, such that the cutting teeth 30 do not project beyond the guard teeth 28. Biasing the cutting blade 24 in this direction is an important safety feature of the cutting assembly 20. The cutting teeth 30 are typically much sharper than the guard teeth 28, and thus biasing the cutting blade 24 to prevent the projection of the cutting teeth 30 improves user safety.

[0036] The bi-directional torsion spring element 34 is coupled between the base 32 and two points on the cutting blade 24 spaced along a direction parallel to the cutting axis 150. The torsion spring element 34 simultaneously prevents the cutting blade 24 from moving away from the base 32 along the y-axis 250, biases the cutting blade 24 with respect to the guard blade 22 perpendicular to the blade plane to ensure that the guard blade 22 and the cutting blade 24 remain in contact, and biases the cutting blade 24 towards a central position along the cutting axis 150 with respect to the base 32.

[0037] The adjustment mechanism 26 has an input device configured to be operated by a user to adjust the cutting assembly 20. In this example, the input device has an elongated rod 40 extending along the rod axis 350 and a wheel 42 at the axial end of the rod 40. In this example, the rod 40 has a plurality of keys 45 (best seen in FIG. 3) spaced along the rod 40. The keys 45 are special-shaped protrusions from the rod 40, which cooperate with corresponding key slots in the gear set to engage with an individual gear set. In this example, the rod axis 350 is parallel to the x-axis 50 and the cutting axis 150.

[0038] The adjustment mechanism 26 in this example is configured to be switched between a y-set configuration, an angle-set configuration, an x-set configuration, and a neutral configuration, which will be described in more detail below with reference to FIGS. 4-7. In some examples, the adjustment mechanism may be configured to perform switching only between the y-set configuration and the neutral configuration. In some examples, the adjustment mechanism can be configured to perform switching only between the y-set configuration, the x-set configuration, and the neutral configuration. In other examples, the adjustment mechanism may be configured to perform switching only between the y-set configuration, the angle configuration, and the neutral configuration.

[0039] In this example, the adjustment mechanism 26 is configured to switch between configurations by moving the input device along the rod axis 350.

[0040] In this example, the adjustment mechanism 26 has a first worm gear 44 and a second worm gear 46 spaced along a direction parallel to the rod axis 350. The first worm gear 44 has a first helical worm 44a and a first worm wheel 44b that mesh together. The second worm gear 46 has a second helical worm 46a and a second worm wheel 46b that mesh together (best shown in FIG. 3). The rod 40 passes through the first helical worm 44a and the second helical worm 46a, such that the first helical worm 44a and the second helical worm 46a are spaced along the rod axis 350.

[0041] In this example, the first worm wheel 44b and the second worm wheel 46b are fixed to the base 32 on opposite sides of the base, and as a result, they rotate about an axis perpendicular to both the x-axis 50 and the y-axis 250. The first worm wheel 44b and the second worm wheel 46b each have eccentric protrusions 44c, 46c, which engage with individual battens 48 protruding from the guard blade 22 and are configured to provide a force along the y-axis 250 to the base 32 that counteracts the force applied to the base 32 by the compression spring 52. Thus, rotation of the first worm wheel 44b and the second worm wheel 46b in the same direction pushes the batten 48 of the guard blade 22 away from the cutting edge of the cutting blade 24, or allows the batten 48 to approach the cutting edge of the cutting blade 24 under the action of the compression spring 52, and as a result, the cutting axis 150 is controllably moved along the y-axis 250.

[0042] In this example, therefore, both the first worm gear 44 and the second worm gear 46 together form a y-gear mechanism, which, when engaged by the first y-key 45a and the second y-key 45b of the input device (i.e., the rod 40), respectively, allows the cutting blade 24 to be moved along the y-axis relative to the guard blade 22 to finely adjust the alignment of the cutting axis 150 and the x-axis 50 during operation of the input device, as best shown in FIGS. 4-7. This will be described in detail below with reference to FIG. 5.

[0043] In this example, the guard blade 22 has a plurality of guard rod holders 54 (best seen in FIG. 3), and the base 32 has a plurality of base rod holders 58. Each of the rod holders 54, 58 has an opening through which the rod 40 is passed and along which the rod 40 is movable along the rod axis 350. In this example, the first helical worm 44a is disposed between a pair of base rod holders 58, and the second helical worm 46a is disposed between another pair of base rod holders 58 spaced apart along a direction parallel to the x-axis 50 to fix each of the helical worms 44a, 46a in a predetermined position along the rod axis 350. The opening in the guard rod holder 54 is elliptical with a longer dimension parallel to the y-axis 250 to allow movement of the rod 40 along the y-axis 250 relative to the guard blade 22.

[0044] In this example, the first worm gear 44 forms an angular gear mechanism by itself (without the second worm gear 46), which allows the cutting blade 24 to rotate relative to the guard blade 22 about an angular axis perpendicular to both the x-axis 50 and the y-axis 250 upon operation of the input device when engaged by the key 45 of the input device. This is described in more detail with reference to FIG. 7. In other examples, the second worm gear 46 can form an angular gear mechanism by itself. Thus, the angular gear mechanism can have a part of the y-gear mechanism. In other examples, there can also be a completely different gear mechanism used to adjust the angle of the cutting blade 24 relative to the guard blade 22. In a further example, there may be no angular gear mechanism.

[0045] In this example, the adjustment mechanism 26 has a third helical worm 56, which in this example is disposed between the first helical worm 44a and the second helical worm 46a. The rod 40 also passes through the third helical worm 56. The third helical worm 56 is configured to engage a base gear of the base 32, which in this example is an internal thread (not shown) of the base 32 that meshes with the external thread of the third helical worm 56, such that rotation of the third helical worm 56 results in movement of the cutting blade 24 along the cutting axis 150 relative to the guard blade 22. In other examples, the third helical worm engages a rack on a base extending parallel to the x-axis 50, enabling movement of the cutting blade along the cutting axis 150 (parallel to the x-axis 50) relative to the guard blade 22. In this example, the third helical worm 56 and the base gear form an x-gear mechanism, which enables the cutting blade 24 to be moved along the x-axis relative to the guard blade 22 under the operation of the input device when engaged by the x-key 45c of the input device (i.e., the rod 40). This is described in detail below with reference to FIG. 6.

[0046] FIG. 4 shows the cutting assembly in the neutral position. In the neutral configuration, the input device is disengaged from the y-gear mechanism, the angular gear mechanism, and the x-gear mechanism, such that the input device can be freely operated (i.e., the wheel 42 can be freely rotated) without causing movement of the cutting blade 24 relative to the guard blade 22 along the y-axis 250 or the cutting axis 150, or any movement due to angular rotation.

[0047] The first helical worm 44a, the second helical worm 46a, and the third helical worm 56 are all locked in place by friction between the elements, which is increased by the biasing element 52 pressing the elements together.

[0048] FIG. 5 shows the cutting assembly 20 in the y-set configuration, where the wheel 42 is pulled away from the guard blade 22 and the cutting blade 24 along the rod axis 350 in order to switch the adjustment mechanism 26 from the neutral configuration to the y-set configuration, and as a result, the adjustment mechanism 26 is engaged with the y-gear mechanism. In this example, the first y-key 45a engages with the first key slot 47a in the first helical worm 44a, and the second y-key 45b engages with the second key slot 47b in the second helical worm 46a, whereby the y-gear mechanism is engaged. The key 45 may be a rectangular protrusion from the rod 40 that interlocks with corresponding rectangular slots in the helical worms 44a, 46a, 56. In other examples, the key 45 and the corresponding interlock slots can have a multi-faceted cross-section, such as a hexagonal cross-section, or a cross-section having more than six sides, such as ten sides. Alternatively, the cross-section may be an angularly repeating cross-section, such as spikes that are angularly repeated many times to form a star shape. The greater the number of repeating angular sections the cross-section has, the more likely it is that rotation of the rod 40 about the rod axis 350 is enabled to move the rod 40 along the rod axis 350 to interlock with the corresponding slots.

[0049] The first y-key 45a and the second y-key 45b are spaced apart along the rod axis 350 by the same amount as the first worm gear 44 and the second worm gear 46 (or, by the same amount as the first helical worm 44a and the second helical worm 46a). As a result, by moving the input device along the rod axis 350 relative to the base 32, the first worm gear 44 and the second worm gear 46 can be simultaneously engaged and disengaged, whereby the first y-key 45a and the second y-key 45b are moved relative to the first worm gear 44 and the second worm gear 46.

[0050] In the y-set configuration, the rotation of the wheel 42 of the input device forces the rotation of the first helical worm 44a and the second helical worm 46a, which in turn forces the corresponding rotation of the first worm wheel 44b and the second worm wheel 46b, thereby causing the cutting blade 24 to move along the y-axis 250 relative to the guard blade 22.

[0051] As shown in FIG. 4, when all the keys 45a - d are disengaged from either or both of the first key slot 47a or the second key slot 47b, the y-gear mechanism is disengaged, and as a result, the rotation of the wheel 42 does not move the cutting blade 24 along the y-axis 250 relative to the guard blade 22.

[0052] Engaging two worm gears spaced along a direction parallel to the x-axis 50 simultaneously in the y-set configuration means that both sides of the cutting blade 24 can be moved simultaneously, reducing the possibility of accidental angular movement of the cutting blade 24 relative to the guard blade 22 without the need for a guide.

[0053] FIG. 6 shows the cutting assembly 20 in the x-set configuration, where the wheel 42 is pulled out further along the rod axis 350 away from the guard blade 22 and the cutting blade 24 from the y-set configuration. As a result, the adjustment mechanism 26 is disengaged from the y-gear mechanism and engaged with the x-gear mechanism. In this example, the x-gear mechanism is engaged by the x-key 45c engaging the third key slot 47c in the third helical worm 56. The x-key 45c is disposed between the first y-key 45a and the second y-key 45b.

[0054] In the x-set configuration, the rotation of the wheel 42 of the input device forces the rotation of the third helical worm 56, which moves the cutting blade 24 along the cutting axis 150 relative to the guard blade 22. Since the y-gear mechanism is disengaged in the x-set configuration, the operation of the wheel 42 does not move the cutting blade 24 along the y-axis 250 relative to the guard blade 22.

[0055] As shown in the neutral configuration in FIG. 4, when all keys 45 are disengaged from the third key slot 47c, the x-gear mechanism is disengaged. As a result, the rotation of the wheel 42 does not move the cutting blade 24 relative to the guard blade 22 along the cutting axis 150 (or x-axis 50).

[0056] Returning to FIG. 5, in the y-set configuration, the x-key 45c is configured to be disengaged from the third helical worm 56. As a result, the operation of the input device does not move the cutting blade 24 relative to the guard blade 22 along the cutting axis 150, but only moves the cutting blade 24 relative to the guard blade 22 along the y-axis 250.

[0057] FIG. 7 shows the cutting assembly 20 in the angle-set configuration, where the wheel 42 is further withdrawn along the rod axis 350 from the x-set configuration. As a result, the adjustment mechanism 26 is disengaged from the y-gear mechanism and the x-gear mechanism, and the adjustment mechanism 26 is engaged with the angle-gear mechanism.

[0058] In this example, the angle-gear mechanism is engaged by the engagement of the angle key 45d with the first key slot 47a in the first helical worm 44a. In this example, the angle key 45d is disposed between the first y-key 45a and the second y-key 45b. In this example, the angle key 45d is disposed between the first y-key 45a and the x-key 45c.

[0059] In the angle-set configuration, the rotation of the wheel 42 of the input device forces the rotation of the first helical worm 44a, which forces the rotation of the first worm wheel 44b, which results in the angular rotation of the cutting blade 24 relative to the guard blade 22. Since the y-gear mechanism and the x-gear mechanism are disengaged in the angle-set configuration, the operation of the wheel 42 does not move the cutting blade 24 relative to the guard blade 22 along the y-axis 250, or along the x-axis 50 or the cutting axis 150.

[0060] Returning to FIGS. 5 and 6 for description, in the y-set configuration and the x-set configuration, the angle key 45d is configured to disengage from the first helical worm 44a. As a result, the operation of the input device does not angularly rotate the cutting blade 24 relative to the guard blade 22.

[0061] In this example, switching between the neutral configuration, the y-set configuration, the x-set configuration, the angle-set configuration, or any suitable combination of these configurations is achieved by pulling the rod 40 along the rod axis 350 to engage and disengage various keys on the rod 40 with the y-gear mechanism, the x-gear mechanism, and the angle-gear mechanism. The input device of this example is described as an elongated rod with a wheel, but in other examples, the input device can be any suitable form of input part that can be operated by the user to switch the adjustment mechanism between the y-set configuration and the neutral configuration, and optionally between the x-set configuration and / or the angle configuration. In a further example, the input device such as the rod and the wheel can be arranged at any angle relative to the blade. As a result, the rod axis of the rod extends in a direction perpendicular to the x-axis or the cutting axis and parallel to the y-axis, and when the adjustment mechanism is engaged with the corresponding y-gear mechanism, the movement of the cutting blade along the y-axis is enabled.

[0062] It should be understood that the spacing of the keys on the input device can be configured to suit any order or combination of configurations. It should also be understood that in some examples, there is no wheel 42 at the end of the rod, and instead the user can operate the rod 40 itself. The wheel 42 improves the ergonomics of the adjustment mechanism 26 for the user by making the rod 40 easier to grip and turn, but the wheel can be any suitable feature that makes the rod easier to grip and turn.

[0063] For optimal shaving, the cutting axis 150 should be aligned as close as possible to the x-axis 50 along the y-axis. Therefore, it is highly useful to be able to finely adjust the position of the cutting blade 24 along the y-axis 250. Further, being able to switch between the neutral configuration and the y-set configuration means that accidental movement of the cutting blade 24 relative to the guard blade 22 due to accidental operation of the input device can be avoided simply by placing the adjustment mechanism 26 in the neutral configuration. Further, being able to switch between other configurations allows the position of the cutting blade 24 relative to the guard blade 22 to be finely adjusted to an optimal position. This is because each direction can be controlled independently.

[0064] Modifications to the disclosed embodiments can be understood and implemented by those skilled in the art who practice the principles and techniques described herein upon consideration of the figures, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. One processor or other unit can perform the functions of a plurality of items recited in the claims. The mere fact that certain means are recited in mutually different dependent claims does not indicate that a combination of these means cannot be used advantageously. A computer program can be stored or distributed in a suitable medium, such as an optical storage medium or a solid-state medium, supplied together with or as part of other hardware, but can also be distributed in other forms, such as via the Internet or other wired or wireless communication systems. Any reference signs in the claims should not be construed as limiting the scope of the invention.

Claims

1. A cutting assembly for a hair cutting device, comprising a plurality of guard teeth and a guard blade defining an x-axis passing through the tips of the guard teeth, the plurality of guard teeth being arranged along an upper edge of the guard blade, the guard blade; a cutting blade that cooperates with the guard blade to cut hair, the cutting blade including a plurality of cutting teeth, the plurality of cutting teeth extending along a cutting edge of the cutting blade and defining a cutting axis passing through the tips of the cutting teeth, the cutting blade; the guard blade being assembled adjacent to the cutting blade; the guard blade and the cutting blade sliding relative to each other within a blade plane while maintaining contact with each other; the guard teeth and the cutting teeth overlapping; and the cutting axis being parallel to the x-axis; the cutting blade reciprocates along the cutting axis relative to the guard blade, and the cutting teeth and the guard teeth cooperate to cut hair; the cutting assembly further having an adjustment mechanism including an input device operable by a user, the adjustment mechanism being switchable between a neutral configuration and a y-set configuration; in the y-set configuration, the input device of the adjustment mechanism is engaged with a y-gear mechanism, and operation of the input device forces movement of the y-gear mechanism, the movement being to align the cutting axis and the x-axis within the blade plane, and to move the cutting blade along the y-axis within the blade plane and perpendicular to the x-axis relative to the guard blade; in the neutral configuration, the input device is disengaged from the y-gear mechanism; the input device is freely operable without moving the cutting blade along the y-axis relative to the guard blade, the cutting assembly.

2. The input device of the adjustment mechanism has an elongated rod extending along a rod axis and a wheel at an axial end of the rod, the input device being movable along the rod axis relative to the y-gear mechanism to engage and disengage with the y-gear mechanism, and the adjustment mechanism being switchable between the y-set configuration and the neutral configuration respectively, the cutting assembly according to claim 1.

3. The y-gear mechanism has a first worm gear and a second worm gear that are spaced apart along a direction parallel to the x-axis and fixed by a base, the base being coupled to the cutting blade, the first worm gear and the second worm gear each having a first helical worm meshed with a first worm wheel and a second helical worm meshed with a second worm wheel, and when engaged simultaneously by the input device in the y-set configuration, the first worm gear and the second worm gear move the cutting blade along the y-axis relative to the guard blade. The cutting assembly according to claim 1 or 2.

4. The rod has a first y-key and a second y-key spaced apart along the rod axis by the same amount as the first worm gear and the second worm gear, the rod passing through the first helical worm and the second helical worm. In the y-set configuration, the first y-key engages the first helical worm, the second y-key engages the second helical worm, rotation of the wheel of the input device forces rotation of the first helical worm and the second helical worm, which forces corresponding rotation of the first and second worm wheels, and the cutting blade is moved along the y-axis relative to the guard blade. In the neutral configuration, the first y-key and the second y-key are disengaged from the first and second helical worms, and rotation of the wheel of the input device does not move the cutting blade relative to the guard blade. The cutting assembly according to claim 2 or 3.

5. The guard blade has a plurality of rod holders including openings through which the rod passes, the rod being movable along the rod axis, and the openings in the rod holders are elliptical to allow movement of the rod along the y-axis. The cutting assembly according to claim 3 or 4.

6. The biasing element is disposed between the guard blade and the base, the biasing element biases the base away from the guard blade, the cutting axis is biased away from the x-axis in a direction towards the guard blade, and the cutting teeth do not project beyond the guard teeth. The cutting assembly according to any one of claims 3 to 5.

7. The first worm wheel and the second worm wheel have eccentric protrusions, and the protrusions engage with individual battless of the guard blade to apply a force from the base to the guard blade that counteracts the force applied to the guard plate by the biasing element, and by operating the input device, fine adjustment of the position of the cutting axis along the y-axis with respect to the guard blade is enabled. The cutting assembly according to claim 6.

8. The adjustment mechanism can be further switched to an x-set configuration, in which the input device is disengaged from the y-gear mechanism and engages with an x-gear mechanism that moves the cutting blade along the cutting axis, and the operation of the input device forces the movement of the x-gear mechanism, and the movement moves the cutting blade along the cutting axis with respect to the guard blade. The cutting assembly according to any one of claims 1 to 7.

9. The x-gear mechanism is disposed between the first worm gear and the second worm gear and has a third helical worm that engages with a base gear of the base. When the third helical worm is rotated by the input device, the cutting blade is moved along the cutting axis with respect to the guard blade. The cutting assembly according to claim 3 or 8.

10. The base gear has an internal thread on the base that corresponds to the external thread of the third helical worm. The cutting assembly according to claim 9.

11. The rod has an x-key disposed between the first y-key and the second y-key. In the y-set configuration, the x-key is disengaged from the third helical worm, and the operation of the input device does not move the cutting blade along the cutting axis. In the x-set configuration, the x-key engages with the third helical worm, the first y-key is disengaged from the first helical worm of the first worm gear, the second y-key is disengaged from the second helical worm of the second worm gear, the operation of the input device forces the rotation of the third helical worm, the cutting blade is moved along the cutting axis with respect to the guard blade, and the cutting blade is not moved along the y-axis with respect to the guard blade. In the neutral configuration, the x key is disengaged from the third helical worm, and operation of the input device does not move the cutting blade relative to the guard blade. The cutting assembly according to claim 9 or 10, dependent on claim 4.

12. The adjustment mechanism is further switchable to an angle setting configuration, in which the input device is disengaged from the y gear mechanism and engaged with an angle gear mechanism, and operation of the input device forces movement of the angle gear mechanism, the movement rotating the cutting blade about an angle axis perpendicular to both the cutting axis and the y axis. The cutting assembly according to any one of claims 1 to 11.

13. The angle gear mechanism has a part of the y gear mechanism. The cutting assembly according to claim 12.

14. In the angle setting configuration, an angle key engages with the first helical worm or the second helical worm, the first y key is disengaged from the first helical worm, the second y key is disengaged from the second helical worm, the x key is disengaged from the third helical worm, and operation of the input device results in angular rotation of the cutting blade relative to the guard blade and does not move the cutting blade along the cutting axis or along the y axis relative to the guard blade. The cutting assembly according to claim 14, dependent on claim 4 or 11.

15. A hair cutting device, comprising: a handle; the cutting assembly according to any one of claims 1 to 14; and a drive mechanism for reciprocating the cutting blade along a cutting axis relative to a guard blade. A hair cutting device.

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