Pruning blade with protective teeth and tool bit assembly

Abstract

The utility model relates to a trimming blade with protective teeth and a cutting head assembly, which are characterized in that a cutting surface sinks along the surface of a substrate to form a swing groove when viewed from the orthographic projection of the substrate in the thickness direction, and one side of the cutting surface and the tooth tips of all fixed teeth are arranged at intervals, so that the protective teeth are formed at the tooth tips of all the fixed teeth; and each protective tooth intersects with the tooth tip of the corresponding fixed tooth but extends in a direction different from that of the fixed tooth. The utility model has the beneficial effects that the local surface of the substrate is ground to form the cutting surface, and the whole surface of the substrate does not need to be ground, so that the grinding workload is reduced, the processing difficulty of the substrate is reduced, the production benefit is improved, and the production cost is reduced; secondly, the edge of the cutting face and the tooth tips of the fixed teeth are arranged at intervals to form the protection teeth, under the condition that blocking of the protection teeth to the hair is reduced, the hair feeding amount of the fixed cutter is increased, the hair trimming effect is improved, meanwhile, the protection teeth can be used for isolating the movable cutter, the movable cutter teeth of the movable cutter are prevented from making direct contact with the skin, and the use safety of the fixed cutter is improved.

Description

Technical Field

[0001] The utility model relates to a hair trimming tool, more particularly to a trimming blade with teeth guards for trimming hair and a cutter head assembly comprising the trimming blade, and is mainly used in the field of hair clippers or hair trimming tools. Background Art

[0002] Existing blade assemblies used for trimming hair, beards, and other types of hair primarily consist of a fixed blade and a movable blade that reciprocates along the blade. The fixed blade is equipped with a fixed tooth group consisting of several spaced-apart fixed teeth and fixed tooth grooves, while the movable blade is equipped with a corresponding movable tooth group consisting of several movable teeth and movable tooth grooves that cooperate with the fixed tooth group to cut hair. During use, the fixed blade comes into direct contact with the skin, and the fixed teeth are mostly cut by a grinding wheel. The sharp tips of the fixed teeth can easily injure the skin, posing a safety hazard. Utility Model Content

[0003] In order to solve the above technical problems, the utility model provides a trimming blade and a cutter head assembly with tooth guards. By changing the structure of the fixed teeth on the safety fixed blade, not only can the safety of use during hair trimming be ensured; at the same time, by controlling the height of the tooth guards, the hair feeding efficiency can be improved and the residual length of the hair roots can be reduced during shaving and cutting, thereby improving the hair trimming effect.

[0004] To solve the above technical problems, the technical solution adopted by the utility model is a trimming blade with tooth guards, comprising a base plate, a fixed tooth group provided at the edge of one end of the base plate, the fixed tooth group comprising a plurality of fixed teeth arranged side by side and spaced apart along the edge of one end of the base plate, and fixed tooth grooves formed between adjacent fixed teeth; the length of the fixed tooth group is less than the width of the base plate, wherein:

[0005] As viewed from the orthographic projection of the substrate surface, a cutting surface is provided on the substrate at the fixed tooth group, which is greater than the length of the fixed tooth group but equal to or less than the width of the substrate. The height of the cutting surface is less than the height of the substrate, and the upper edge of the cutting surface is spaced from the tooth tips of each fixed tooth in the fixed tooth group. The lower edge of the cutting surface is at least flush with the bottom of the fixed tooth groove between adjacent fixed teeth or extends beyond the bottom of the fixed tooth groove and is located outside the bottom of the fixed tooth groove.

[0006] From the perspective of the orthographic projection in the thickness direction of the substrate, the cutting surface sinks along the surface of the substrate to form a swinging groove, and one side of the cutting surface is spaced apart from the tooth tip of each fixed tooth, so that a guard tooth is formed at the tooth tip of each fixed tooth. Each guard tooth intersects with the corresponding tooth tip of the fixed tooth but has a different extension direction from the fixed tooth.

[0007] Preferably, a skin-contacting surface in contact with the skin is formed on the base sheet, and the cutting surface is inclined relative to the skin-contacting surface but parallel to the other surface of the base sheet, so that the tip thickness of the fixed teeth is smaller than the root thickness.

[0008] Preferably, when viewed from the thickness orthographic projection direction of the substrate, the height of each tooth guard is greater than or less than the depth of the swing groove; or, the height of each tooth guard is equal to the depth of the swing groove.

[0009] Preferably, each tooth guard is formed at the tooth tip of the corresponding fixed tooth and is inclined relative to the fixed tooth.

[0010] Preferably, the shortest distance between the cutting surface and the skin-contacting surface does not exceed 0.6 mm so that the thickness of the tooth tip of the fixed tooth is greater than the height of the tooth guard.

[0011] Preferably, viewed from the orthographic projection direction of the substrate surface, the width of the guard teeth formed at the tooth tip of each fixed tooth matches the width of the tooth tip, and the opening width of the fixed tooth groove between adjacent fixed teeth is greater than the width of the tooth tip.

[0012] Preferably, each toothbrush is inclined relative to the cutting surface toward the tip of the fixed tooth, an inner guide arc surface is formed at the connection between the inner side surface of the toothbrush and the fixed tooth, an outer guide arc surface is formed on the outer side surface of the toothbrush, and the skin-contacting surface is tangentially connected to the outer guide arc surface as a whole; wherein,

[0013] The outer guide arc surface and the inner guide arc surface extend toward the end of the mouthpiece and gradually narrow, so that the thickness of the end of the mouthpiece is smaller than the thickness of the connection between the mouthpiece and the fixed teeth;

[0014] Alternatively, the outer guide arc surface and the inner guide arc surface extend toward the end of the mouthpiece and gradually widen, so that the thickness of the end of the mouthpiece is greater than the thickness of the connection between the mouthpiece and the tooth tip of the fixed tooth.

[0015] Preferably, sliding arc surfaces are formed at the ends of the outer guide arc surface and the inner guide arc surface of each toothbrush so that the end surface of each toothbrush is arc-shaped, and the thickness of the end of the toothbrush is less than or greater than the thickness of the connection between the toothbrush and the fixed tooth.

[0016] Preferably, the maximum cross-section of each tooth guard is not less than 0.35mm when viewed from the positive projection direction of the tooth tip of the fixed tooth. 2 .

[0017] On the basis of the above-mentioned trimming blade with tooth guard, the applicant also proposed a technical solution for a cutter head assembly, comprising the above-mentioned trimming blade with tooth guard and a movable knife that swings back and forth along the trimming blade with tooth guard, wherein the movable knife is provided with a movable tooth group consisting of a plurality of movable knife teeth and movable tooth grooves, the length of the movable tooth group is less than the height of the cutting surface and is covered above the fixed tooth group, and when viewed from the thickness projection direction of the substrate, the distance between the tooth tip of each movable knife tooth in the movable tooth group and the extension line of the perpendicular line of the outermost point of the tooth guard is between 0.3 mm and 1.2 mm.

[0018] The beneficial effects of the utility model are:

[0019] 1. Compared with the traditional method of processing the entire surface of the substrate, by setting a cutting surface on the local surface of the substrate and sinking it along the surface of the substrate to form a swing groove, only the cutting surface needs to be ground, and there is no need to grind the entire surface of the substrate, which greatly reduces the processing workload of the fixed knife in the production process and effectively reduces the production cost.

[0020] 2. The cutting surface is sunken along the local surface of the substrate, which relatively reduces the cutting surface height (the cutting surface width when projected from the thickness direction of the substrate). Compared with processing the entire substrate surface, reducing the cutting surface height and the cutting surface processing accuracy is higher, and the minimum flatness of the cutting surface can be controlled within 0.02mm. When the movable knife swings back and forth along the cutting surface, the friction resistance between the movable knife and the fixed knife is smaller, which effectively reduces the temperature rise between the movable knife and the fixed knife, and improves the comfort of using the fixed knife.

[0021] 3. After the cutting surface sinks along the local surface of the substrate to form a swing groove, the two side walls of the swing groove can limit the movable tooth group of the movable knife, avoiding dislocation of the movable knife when it swings back and forth along the cutting surface driven by the driving mechanism, thereby improving the hair trimming performance of the movable knife and the fixed knife. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a front view of a trimming blade with a tooth guard according to an embodiment of the present invention.

[0023] Figure 2 A three-dimensional diagram of a trimmer blade with a tooth guard according to an embodiment of the present invention

[0024] Figure 3 This is a cross-sectional view of a trimming blade with a tooth guard according to an embodiment of the present invention.

[0025] Figure 3A for Figure 3 Enlarged view of point P in the middle

[0026] Figure 3B This is an enlarged structural diagram of the first embodiment of the mouthguard in the embodiment of the present utility model

[0027] Figure 3C This is an enlarged structural diagram of the second embodiment of the mouthguard in the embodiment of the present utility model

[0028] Figure 4 for Figure 3 Cross-sectional structural diagram at KK

[0029] Figure 5 This is the main structural diagram of the cutter head assembly of the utility model embodiment

[0030] Figure 6 This is a cross-sectional structural diagram of the cutter head assembly of the embodiment of the utility model DETAILED DESCRIPTION

[0031] The following is combined with Figures 1 to 6 The following further describes the implementation of the present invention:

[0032] The present utility model is a trimming blade with tooth guards, which is a fixed knife in actual production or assembly. The "fixed knife" in the following description can be regarded as a "trimming blade with tooth guards 4", and the "trimming blade with tooth guards 4" can also be directly understood as a "fixed knife". Defining the trimming blade with tooth guards 4 as a fixed knife does not mean that the technical solution disclosed in this embodiment can only be applied to the fixed knife. The technical solution disclosed in the embodiment can also be adopted on the movable knife 6 according to actual conditions or needs. The trimming blade with tooth guards 4 includes a substrate 1, which is a sheet of material with a certain thickness and two surfaces. A fixed tooth group 2 is provided at the end edge of one of the surfaces of the substrate 1. The fixed tooth group 2 is composed of a plurality of fixed teeth 21 arranged side by side and spaced apart along one end edge of the substrate 1 and fixed tooth grooves 22 between adjacent fixed teeth 21.

[0033] To enhance the working strength of the fixed tooth group 2, the length of the fixed tooth group 2 is smaller than the width of the substrate 1. By controlling the length of the fixed tooth group 2, the teeth 11 are reinforced between the two side edges of the substrate 1 and the fixed tooth group 2 to ensure the working strength and stability of the fixed blade and the fixed tooth group 2. When trimming hair, the movable blade 6 must swing back and forth along the fixed blade, and the movable tooth group 61 cooperates with the fixed tooth group 2 to cut the hair. It can be seen that the end surface flatness of the fixed tooth group 2 of the fixed blade and the movable tooth group 61 of the movable blade 6 is an important technical indicator in the production process. If the flatness is poor, the frictional resistance when the movable tooth group 61 cooperates with the fixed tooth group 2 will be relatively high, resulting in an increased temperature rise between the fixed blade and the movable blade 6, causing a burning sensation on the user's skin, or even burns. Therefore, during the production and processing of the fixed blade, the entire surface of the substrate 1 needs to be polished to reduce the frictional resistance between the movable blade 6 and the fixed blade as the movable blade 6 swings back and forth along the fixed blade, thereby reducing the temperature rise of the movable blade 6 and the fixed blade. However, since the fixed tool has a certain height (or length), if the entire surface of the fixed tool is ground, not only the grinding workload is large, but the processing efficiency is low; moreover, the surface flatness of the fixed tool is difficult to guarantee after multiple grindings, which invisibly increases the difficulty of processing the fixed tool.

[0034] In order to reduce the processing difficulty of the fixed knife, reduce the friction resistance and temperature rise between the fixed knife and the movable knife 6, and improve the safety and comfort of use, the technical solution adopted in this embodiment is: from the orthographic projection of the surface of the substrate 1, a cutting surface 3 is provided on the substrate 1 at the fixed tooth group 2, which is greater than the length of the fixed tooth group 2 but equal to or less than the width of the substrate 1. The cutting surface 3 is formed by local grinding along the surface of the substrate 1. During actual production, the cutting surface height T2 is less than the substrate height T1 but greater than the length of the movable blade tooth 611. Compared with the conventional processing along the entire surface of the substrate 1, by reducing the cutting surface height T2 (from the thickness direction of the substrate 1, it can also be understood as the width of the cutting surface 3), the flatness of the cutting surface 3 can be effectively improved during the grinding process, which is not only easy to produce and process, but also reduces the processing difficulty and improves production efficiency; at the same time, it can also reduce the friction resistance of the movable blade 6 when it swings back and forth along the cutting surface 3, reduce the temperature rise between the movable blade 6 and the fixed blade, avoid the surface temperature of the fixed blade or movable blade 6 due to high friction resistance, and cause the user's skin to feel scorching or even burn the skin, thereby improving the comfort of using the fixed blade.

[0035] When the cutting surface 3 is actually produced, both ends of the cutting surface 3 can completely pass through the substrate 1, so that multiple substrates 1 can be processed uniformly, thereby improving production efficiency. Of course, in order to improve the working strength of the fixed knife, one end of the cutting surface 3 can also pass through the substrate 1, and the other end can be spaced from the edge of the substrate 1; or the two ends of the cutting surface 3 can be spaced from the two side edges of the substrate 1 (such as Figure 1 (as shown by the two dotted lines in the figure), the spacing between the ends of the cutting surface 3 and the edge of the substrate 1 is used to increase the working strength of the fixed blade. However, this processing method can only process a single fixed blade at a time, and the processing efficiency is relatively low. Therefore, in this embodiment, the two ends of the cutting surface 3 are preferably respectively passed through the two sides of the substrate 1.

[0036] When the cutting surface 3 is formed by grinding along the local surface of the substrate 1, as shown in FIG. Figure 1 As shown, from the orthographic projection of the surface of the substrate 1, the upper edge of the cutting surface 3 (the outer edge of the grinding wheel during grinding) is spaced apart from the tooth tips of each fixed tooth 21 in the fixed tooth group 2, and the lower edge of the cutting surface 3 (the outer edge of the grinding wheel during grinding) is at least flush with the bottom of the fixed tooth groove 22 between adjacent fixed teeth 21 or extends beyond the bottom of the fixed tooth groove 22 and is located outside the bottom of the fixed tooth groove 22. In this way, after the cutting surface 3 is processed and assembled with the movable knife 6, when the movable knife 6 swings back and forth along the fixed knife, the movable tooth group 61 can cover the remaining fixed teeth 21 and fixed tooth groove 22 except for the tooth tips of the fixed teeth 21, thereby preventing the tooth tips of the movable teeth 611 in the movable tooth group 61 from directly contacting the skin, thereby improving safety in use. In addition, it can also prevent hair from entering the bottom of the fixed tooth groove 22 and being unable to be cut by the movable teeth 611, thereby avoiding undesirable phenomena such as hair pulling and hair jamming, thereby improving the hair cutting performance and hair cutting stability of the fixed knife and the movable knife 6.

[0037] Secondly, if Figure 3 and Figure 3A As shown, when projected along the thickness direction of substrate 1, cutting surface 3 is recessed along the surface of substrate 1 to form a swinging groove 7. During assembly, movable teeth 61 of movable blade 6 are positioned within swinging groove 7, abutting against the end surface of cutting surface 3 and, driven by the drive mechanism, swinging back and forth along cutting surface 3 to achieve hair trimming. This structure can produce at least the following beneficial effects:

[0038] (1). Compared with the traditional method of processing the entire surface of the substrate 1, by setting a cutting surface 3 on the local surface of the substrate 1 and sinking the swing groove 7 along the surface of the substrate 1, it is only necessary to grind the cutting surface 3, and there is no need to grind the entire surface of the substrate 1, which greatly reduces the processing workload of the fixed knife in the production process and effectively reduces the production cost.

[0039] (2) The cutting surface 3 is sunken along the local surface of the substrate 1, which relatively reduces the cutting surface height T2 (the width of the cutting surface 3 when projected from the thickness direction of the substrate 1). Compared with processing the entire surface of the substrate 1, reducing the cutting surface height T2, the processing accuracy of the cutting surface 3 is higher, and the flatness of the cutting surface 3 can be controlled to be within 0.02mm. When the movable knife 6 swings back and forth along the cutting surface 3, the friction resistance between the movable knife 6 and the fixed knife is smaller, which effectively reduces the temperature rise between the movable knife 6 and the fixed knife, and improves the comfort of using the fixed knife.

[0040] (3) After the cutting surface 3 sinks along the local surface of the substrate 1 to form the swing groove 7, the two side walls of the swing groove 7 can limit the movable tooth group 61 of the movable knife 6, thereby preventing the movable knife 6 from being misaligned when it swings back and forth along the cutting surface 3 driven by the driving mechanism, thereby improving the hair trimming performance of the movable knife 6 and the fixed knife.

[0041] In order to improve the safety of the fixed knife and prevent the tooth tips of the fixed teeth 21 from piercing the skin, a tooth tip of the fixed tooth 21 is spaced apart from the tooth tip of the fixed tooth 21 on the side of the cutting surface 3 close to the tooth tip. In this way, when the cutting surface 3 sinks along the local surface of the substrate 1 to form a swinging groove 7, a tooth guard 4 will naturally form at the tooth tip of each fixed tooth 21, which not only prevents the tooth tip of the fixed tooth 21 from piercing the skin, but also reduces the processing difficulty of the fixed knife, improves production efficiency and improves the safety of the fixed knife. At the same time, when the movable knife 6 swings back and forth along the cutting surface 3 of the fixed knife, the tooth guard 4 can also isolate the movable tooth group 61 of the movable knife 6 to prevent the movable teeth 611 in the movable tooth group 61 from directly contacting the skin and causing skin cuts, thereby ensuring the safety of the cutter head assembly.

[0042] Each mouthguard 4 intersects with the tooth tip of the corresponding fixed tooth 21 but extends in a different direction from the fixed tooth 21, which means that the mouthguard 4 extends in different directions relative to the fixed tooth 21, such as above or below the fixed tooth 21, or extends above and below at the same time. The mouthguard 4 is used to isolate the movable knife 6 to prevent the movable knife teeth 611 of the movable knife 6 from directly contacting the skin, thereby improving the safety of the fixed knife. Moreover, when the mouthguard 4 faces the skin, the mouthguard 4 can also play a role similar to that of a comb, stimulating the nerves of the head, accelerating the blood circulation and blood oxygen supply of the head skin, thereby making the user feel more comfortable on the skin and improving the comfort of using the fixed knife. The setting direction of the mouthguard 4 can be determined according to the actual needs of the user, and this is not further limited in this embodiment.

[0043] In order to improve the comfort of use and the hair trimming effect of the fixed knife, a skin-contacting surface 5 that contacts the skin is formed on the base plate 1. The cutting surface 3 is inclined relative to the skin-contacting surface 5, but is parallel to the other surface of the base plate 1, so that the thickness of the tooth tip of the fixed tooth 21 is less than the thickness of the tooth root. By setting the skin-contacting surface 5 inclined relative to the cutting surface 3, with its inclination direction toward the tooth tip of the fixed tooth 21, the thickness of the tooth tip of the fixed tooth 21 can be further reduced to be less than the thickness of the tooth root of the fixed tooth 21, and the shortest distance T3 between the cutting surface 3 and the skin-contacting surface 5 in the fixed tooth 21 does not exceed 0.6mm, and is preferably between 0.4mm and 0.5mm. When the skin-contacting surface 5 is inserted into the hair clump in contact with the skin, the movable knife 6 that swings back and forth along the cutting surface 3 can control the remaining length of the hair root to the greatest extent, thereby improving the hair trimming effect. Secondly, the inclined skin-contacting surface 5 not only enables the fixed knife to be quickly inserted into the hair clump along the skin, thereby improving the hair feeding efficiency of the fixed knife; at the same time, the inclined skin-contacting surface 5 also enables the fixed knife to slide more freely on the head, thereby improving the user comfort during hair trimming.

[0044] In order to improve the working strength of the tooth guard 4, the shortest distance T3 between the cutting surface 3 and the skin-contacting surface 5 is greater than the tooth guard height T4 (the tooth guard height T4 can also be regarded as the depth of the swing groove 7), wherein the shortest distance T3 between the cutting surface 3 and the skin-contacting surface 5 means that the tooth tip thickness of the fixed tooth 21 is greater than the tooth guard height T4 when viewed from the thickness direction of the base plate 1; since the tooth guard 4 is formed at the tooth tip of the fixed tooth 21 by grinding the local surface of the base plate 1, when the tooth tip thickness of the fixed tooth 21 is greater than the tooth guard height T4, the working strength of the tooth guard 4 can be effectively improved, and deformation of the tooth tip of the fixed tooth 21 when the tooth guard 4 is subjected to force can be avoided, thereby improving the hair trimming performance.

[0045] To reduce the manufacturing complexity of the fixed blade, the height T4 of each guard should be either greater or less than the depth of the swing groove 7, as viewed from the orthographic projection of the thickness of the substrate 1. If the guard height T4 is greater than the depth of the swing groove 7, the highest point of the guard 4 is above the surface of the substrate 1. This requires grinding the entire surface of the substrate 1 during manufacturing, which is relatively labor-intensive and therefore not optimal. On the other hand, if the guard height T4 is less than the depth of the swing groove 7, the highest point of the guard 4 is below the surface of the substrate 1. This requires preliminary grinding of the substrate 1's edge to reduce the thickness, which increases the number of steps required in the fixed blade production process and correspondingly increases production costs. Therefore, the optimal solution is for each guard height T4 to be equal to the depth of the swing groove 7, meaning that the highest point of the guard 4 is on the same level as the base surface. This allows the cutting surface 3 and the swing groove 7 to be formed directly by grinding the substrate 1 surface with a grinding wheel, simplifying the production process and improving production efficiency, effectively reducing the production cost of the fixed blade.

[0046] In order to prevent the mouthguard 4 from affecting the advancement of the fixed knife and causing undesirable phenomena such as hair pulling, hair getting stuck or hair hooking when the fixed knife is inserted into the hair clump, each mouthguard 4 is formed at the tooth tip of the corresponding fixed tooth 21 and is inclined relative to the fixed tooth 21. When trimming hair, the user will insert the fixed knife into the hair clump. If the mouthguard 4 is perpendicular to the fixed tooth 21, the outer side of the mouthguard 4 will hinder the hair, delaying the advancement of the fixed knife and even affecting the user's comfort. Secondly, when the fixed knife exits the hair clump, the inner side of the mouthguard 4 will also hook or pull the hair, causing the user to experience pulling pain. Therefore, the mouthguard 4 is preferably inclined relative to the fixed tooth 21, and the inclination angle a of the mouthguard 4 relative to the fixed tooth 21 is: 90°>a≥150°. In actual production, the inclination angle of the mouthguard 4 relative to the fixed tooth 21 is 110°. By defining the inclination angle between the guard 4 and the fixed teeth 21, the outer and inner sides of the guard 4 form a slope. When the fixed blade is inserted into a hair clump, the inner and outer sides of the guard 4 guide the hair. When advancing, it can separate the hair faster than the fixed teeth 21, speeding up the hair entry into the fixed tooth groove 22, improving hair feeding efficiency and hair cutting performance. When the fixed blade exits the hair clump, the inner side of the guard 4 guides the hair out, preventing hair jamming, hair pulling, and other undesirable phenomena, thereby improving the comfort of the fixed blade.

[0047] To improve hair feeding efficiency and reduce hair obstruction by the mouthpiece 4, the mouthpiece width T5 formed at the tip of each fixed tooth 21 matches the tip width, as viewed from the orthographic projection of the substrate 1 surface, and the opening width of the fixed tooth slot 22 between adjacent fixed teeth 21 is greater than the tip width. While limiting the mouthpiece height T4 as described above, by controlling the mouthpiece width T5 to match the tip width of the fixed teeth 21 and ensuring that the fixed tooth slot opening width T6 is greater than the tip width, hair obstruction by the mouthpiece 4 is minimized. Furthermore, increasing the fixed tooth slot opening width T6 facilitates hair introduction, thereby increasing hair feeding by the fixed blade and improving hair trimming results. Of course, in actual production, the guard teeth 4 can also be made to extend beyond the side walls of the fixed teeth 21 on one or both sides. Although this structure will relatively increase the barrier effect of the guard teeth 4 on hair and reduce the amount of hair entering, by having one or both sides of the guard teeth 4 extend beyond the side walls of the fixed teeth 21, the speed at which hair slides out of the fixed tooth groove 22 can be slowed down, blocking or delaying the escape of hair that has entered the fixed tooth groove 22, buying time for the swing cutting of the movable blade 6, and relatively improving the hair trimming effect. However, using this structure, the production and processing of the fixed tooth groove 22 is somewhat difficult. Therefore, the embodiment of this embodiment is the preferred embodiment.

[0048] Since the above definition stipulates that the mouthguard 4 is inclined relative to the fixed teeth 21, in order to avoid the phenomenon of hair pulling or hair jamming at the connection between the tooth tips of the mouthguard 4 and the fixed teeth 21, an inner guide arc surface 41 is formed at the connection between the inner side surface of the mouthguard 4 and the fixed teeth 21. The inner guide arc surface 41 is formed by grinding the grinding wheel along the local surface of the substrate 1. By providing the inner guide arc surface 41, no matter whether the fixed knife is inserted into the hair clump with the skin-contacting surface 5 in contact with the skin, or is inserted into the hair clump with the other end relative to the skin-contacting surface 5 in contact with the skin, the inner guide arc surface 41 can play a guiding and sliding role, preventing the phenomenon of hair pulling or hair jamming, and improving the comfort of use of the fixed knife; and, when the fixed knife exits the hair clump, the inner guide arc surface 41 can also guide the hair to exit quickly, preventing the mouthguard 4 from hooking the hair, and improving the convenience and comfort of use of the fixed knife.

[0049] When trimming hair, the fixed knife needs to be inserted into the hair clump. In order to prevent the joint between the mouthguard 4 and the fixed teeth 21 from interfering with the advancement of the fixed knife, an outer guide arc surface 42 is formed on the outer side of the mouthguard 4. The outer guide arc surface 42 is formed by grinding along the local surface of the substrate 1 at one time, and is tangentially connected to the skin-contacting surface 5 as a whole. In actual production, the arc radius of the outer guide arc surface 42 is greater than or equal to 0.5 mm. By limiting the outer guide arc surface 42 of the mouthguard 4 to a radius of not less than 0.5 mm, when the fixed knife is advanced along the skin, the outer guide arc surface 42 of the mouthguard 4 can accelerate the advancement of the fixed knife, making the advancement process smoother; secondly, it can also prevent the outer side of the mouthguard 4 from causing punctures or cuts to the skin, thereby improving the safety of the fixed knife.

[0050] During hair trimming, especially when cutting hair, barbers will use different grips to hold the cutting tool depending on the location of hair growth. For example, when trimming the temples above the ears on both sides of the head or the back of the neck, barbers typically hold the cutting tool perpendicular to the skin, using the outer end surface of the fixed teeth 21 of the fixed blade to scrape up and down the hair. To prevent the fixed blade from cutting the skin when scraping perpendicularly up and down, sliding arc surfaces 43 are formed at the ends of the outer guide arc surface 42 and the inner guide arc surface 41 of each guard 4, giving the end surface of each guard 4 an arc shape. The thickness T7 of the end of the guard 4 is less than or greater than the thickness T8 at the connection between the guard 4 and the fixed teeth 21. By forming an arc-shaped sliding surface 43 at the tooth end of the mouthguard 4, no matter which side of the mouthguard 4 faces the skin, the sliding arc surface 43 can make the mouthguard 4 slide along the skin more smoothly, so that the fixed knife can trim the hair more smoothly when it is perpendicular to the skin, thereby improving the comfort and safety of using the fixed knife and effectively preventing the fixed knife from stabbing or cutting the skin.

[0051] To improve the working strength of the mouthguard 4, the outer guide arc surface 42 and the inner guide arc surface 41 of the mouthguard 4 extend toward the end of the mouthguard 4 and gradually narrow, so that the thickness T7 of the end of the mouthguard 4 is less than the thickness T8 of the connection between the mouthguard 4 and the fixed teeth 21. By controlling the outer guide arc surface 42 and the inner guide arc surface 41 of the mouthguard 4 to gradually narrow along the end of the mouthguard 4, the thickness T8 of the connection between the mouthguard 4 and the fixed teeth 21 can be correspondingly increased, so that the end and root of the mouthguard 4 (that is, the connection between the tooth tips of the mouthguard 4 and the fixed teeth 21) have different thicknesses. When the mouthguard 4 contacts the skin and is subjected to force, the increase in the thickness T8 of the connection between the mouthguard 4 and the fixed teeth 21 can effectively improve the working strength of the mouthguard 4, prevent the mouthguard 4 from deformation, and thus improve the working stability of the mouthguard 4. Secondly, the narrower thickness T7 of the end of the mouthpiece 4 can also pre-lift the hair when the fixed blade is inserted into the hair clump, increasing the amount of hair that the fixed blade can insert at a time, reducing the user (i.e., the barber) from having to repeat multiple operations at the same location, reducing workload, and improving hair trimming efficiency. When the fixed blade is shaving in the opposite direction, the mouthpiece 4 can directly contact the skin. The narrower mouthpiece 4 can also act like the teeth of a comb, stimulating the head nerves, accelerating blood circulation and blood oxygen supply to the head skin, thereby providing the user with a more comfortable skin feel and improving the comfort of using the fixed blade. Of course, the outer guide arc surface 42 and the inner guide arc surface 41 can also extend toward the end of the mouthpiece 4 and gradually widen, so that the thickness T7 of the end of the mouthpiece 4 is greater than the thickness T8 at the connection between the tooth tips of the mouthpiece 4 and the fixed teeth 21. However, gradually widening the mouthpiece 4 is more difficult to process, so the embodiment mode of this embodiment is the preferred implementation mode.

[0052] In order to minimize the obstruction of the mouthguard 4 on the hair, increase the amount of hair entering the fixed tooth groove 22, and improve the hair trimming efficiency, the maximum cross-sectional area of each mouthguard 4 is not greater than 0.35mm when viewed from the positive projection direction of the tooth tip of the fixed tooth 21. 2, but smaller than the cross-sectional area between the tooth width of the fixed tooth 21 and the thickness of the substrate 1.

[0053] like Figures 5-6 As shown, based on the above-mentioned safety trimming blade, the applicant also proposes a technical solution for a cutter head assembly, including the above-mentioned trimming blade with a tooth guard and a movable blade 6 that reciprocates along the trimming blade with a tooth guard. The movable blade 6 is provided with a movable tooth group 61 consisting of a plurality of movable blade teeth 611 and movable tooth grooves 612. The length of the movable tooth group 61 is less than the cutting surface height T2 and is placed above the fixed tooth group 2. In addition, when viewed from the orthographic projection direction of the thickness of the substrate 1, the distance T9 between the tooth tip of each movable blade tooth 611 in the movable tooth group 61 and the extension line of the perpendicular to the outermost point of the tooth guard 4 is between 0.3mm and 1.2mm, preferably less than 0.8mm and greater than 0.5mm. When a barber needs to trim the user's head behind the ears or the back of the neck, the cutter head cannot fit the skin well for trimming due to the body curve at the ears or the back of the neck. To this end, the barber will make the cutter head component perpendicular to the skin and directly use the fixed teeth 2121 of the safety trimming blade to contact the skin. At this time, the distance between the movable cutter teeth 611 of the movable cutter 6 and the guard teeth 4 of the safety trimming blade directly determines the length of the hair roots remaining on the skin. By setting the distance T9 between the tooth tip of the movable cutter tooth 611 and the outermost point of the guard teeth 4 to be less than 0.8mm and greater than 0.5mm, the cutter head assembly can form a fine cut. After the trimming is completed, there is no need to use a manual razor (also called a scraper, which is the most common manual blade used in barber shops for fine trimming along the skin surface) for secondary fine trimming, thereby avoiding consumer disputes caused by cutting the skin due to improper operation.

[0054] The above embodiments should not be regarded as limiting the present invention, but any improvements based on the spirit of the present invention should be within the scope of protection of the present invention.

Claims

1. A trimmer blade with tooth guards, comprising a base plate (1), a fixed tooth group (2) provided at an edge of one end of the base plate (1), the fixed tooth group (2) comprising a plurality of fixed teeth (21) arranged side by side and spaced apart along the edge of one end of the base plate (1), and fixed tooth grooves (22) formed between adjacent fixed teeth (21); characterized in that The length of the fixed tooth group (2) is smaller than the width of the substrate (1), wherein: From the orthographic projection of the substrate (1) surface, a cutting surface (3) is provided on the substrate (1) at the fixed tooth group (2), which is greater than the length of the fixed tooth group (2) but equal to or less than the width of the substrate (1); the height (T2) of the cutting surface is less than the substrate height (T1); the upper edge of the cutting surface (3) is spaced from the tooth tip of each fixed tooth (21) in the fixed tooth group (2); and the lower edge of the cutting surface (3) is at least flush with the bottom of the fixed tooth groove (22) between adjacent fixed teeth (21) or exceeds the bottom of the fixed tooth groove (22) and is located outside the bottom of the fixed tooth groove (22); When viewed from the orthographic projection in the thickness direction of the substrate (1), the cutting surface (3) is sunken along the surface of the substrate (1) to form an oscillating groove (7), and one side of the cutting surface (3) is spaced apart from the tooth tips of each fixed tooth (21), so that a guard tooth (4) is formed at the tooth tip of each fixed tooth (21), and each guard tooth (4) intersects with the tooth tip of the corresponding fixed tooth (21) but has a different extension direction from the fixed tooth (21).

2. The trimming blade with teeth guard according to claim 1, characterized in that A skin-contacting surface (5) in contact with the skin is formed on the base sheet (1), and the cutting surface (3) is inclined relative to the skin-contacting surface (5) but parallel to the other surface of the base sheet (1), so that the thickness of the tooth tip of the fixed tooth (21) is smaller than the thickness of the tooth root.

3. The trimming blade with teeth guard according to claim 1, characterized in that Viewed from the thickness orthographic projection direction of the substrate (1), the height (T4) of each tooth guard is greater than or less than the depth of the swing groove (7); or, the height (T4) of each tooth guard is equal to the depth of the swing groove (7).

4. The trimming blade with teeth guard according to claim 1, characterized in that Each guard tooth (4) is formed at the tooth tip of the corresponding fixed tooth (21) and is inclined relative to the fixed tooth (21).

5. The trimming blade with teeth guard according to claim 2, characterized in that The shortest distance (T3) between the cutting surface (3) and the skin-contacting surface (5) does not exceed 0.6 mm, so that the thickness of the tooth tip of the fixed tooth (21) is greater than the tooth guard height (T4).

6. The trimmer blade with teeth guard according to claim 1, characterized in that Viewed from the orthographic projection direction of the substrate (1) surface, the tooth guard width (T5) formed at the tooth tip of each fixed tooth (21) matches the tooth tip width, and the fixed tooth slot opening width (T6) between adjacent fixed teeth (21) is greater than the tooth tip width.

7. The trimmer blade with teeth guard according to claim 1, characterized in that Each tooth guard (4) is inclined relative to the cutting surface (3) toward the tip of the fixed tooth (21), an inner guide arc surface (41) is formed at the connection between the inner side surface of the tooth guard (4) and the fixed tooth (21), an outer guide arc surface (42) is formed on the outer side surface of the tooth guard (4), and the skin-contacting surface (5) is tangentially connected to the outer guide arc surface (42) as a whole; wherein, The outer guide arc surface (42) and the inner guide arc surface (41) extend toward the end of the tooth guard (4) and gradually narrow, so that the thickness (T7) of the end of the tooth guard (4) is smaller than the thickness (T8) of the connection between the tooth guard (4) and the fixed tooth (21); Alternatively, the outer guide arc surface (42) and the inner guide arc surface (41) extend toward the end of the tooth guard (4) and gradually widen, so that the thickness (T7) of the end of the tooth guard (4) is greater than the thickness (T8) of the connection between the tooth guard (4) and the tooth tip of the fixed tooth (21).

8. The trimmer blade with teeth guard according to claim 1, characterized in that A sliding arc surface (43) is formed at the end of the outer guide arc surface (42) and the inner guide arc surface (41) of each guard tooth (4), so that the end surface of each guard tooth (4) is in an arc shape, and the thickness (T7) of the end of the guard tooth (4) is less than or greater than the thickness (T8) of the connection between the guard tooth (4) and the fixed tooth (21).

9. The trimming blade with teeth guard according to claim 1, characterized in that The maximum cross section of each guard tooth (4) is not less than 0.35mm when viewed from the positive projection direction of the tooth tip of the fixed tooth (21). 2 .

10. A cutter head assembly, characterized in that The invention comprises a trimming blade with a tooth guard according to any one of claims 1 to 9 and a movable knife (6) that swings back and forth along the trimming blade with the tooth guard, wherein the movable knife (6) is provided with a movable tooth group (61) consisting of a plurality of movable knife teeth (611) and movable tooth grooves (612), the length of the movable tooth group (61) is less than the cutting surface height (T2) and is covered above the fixed tooth group (2), and the distance (T9) between the tooth tip of each movable knife tooth (611) in the movable tooth group (61) and the extension line of the perpendicular line of the outermost point of the tooth guard (4) is between 0.3 mm and 1.2 mm when viewed from the thickness projection direction of the substrate (1).

Images