A fixed-axis rotating variable jaw guard helmet

Abstract

The present invention relates to a variable chin guard helmet, which uses a first constraint body and a second constraint body to form a kinematic matching pair and is combined with a displacement obtaining mechanism, thereby achieving the goal of constraining the chin guard fork handle to rotate around a fixed axis and to make an opening and closing displacement movement relative to the symmetric plane of the helmet shell body. When the chin guard is in the full helmet structure, the fork handle can be retracted to appear to be in a retracted state relative to the helmet shell body, which is beneficial for the helmet to obtain a good aerodynamic shape. When the chin guard is flipped, the fork handle can be extended outward to avoid being restrained by the helmet shell body and the shield without affecting its conversion between the full helmet structure position and the half helmet structure position. Because the abrupt convex fork handle layout of the traditional variable chin guard helmet is abandoned, the airflow whistling sound can be reduced and the volume can be reduced, thereby improving the comfort and storage of the helmet. Because the retracted fork handle can directly transmit the impact force on the chin guard to the helmet shell body, the force characteristics can be improved, thereby enhancing the safety and reliability of the helmet.

Description

Technical Field

[0001] The present invention belongs to the technical field of safety protection devices, and relates to a helmet for protecting the human head, specifically to a helmet with a jaw guard protection structure, and more specifically to a helmet in which the jaw guard can be rotated on a fixed axis to change its position and posture. Background Art

[0002] People should wear helmets to protect their heads when riding motorcycles, racing cars, racing boats, self-balancing scooters, aircraft, or electric bikes or bicycles. Furthermore, helmets are also necessary when performing tasks in places like spray painting workshops, firefighting and disaster relief, counter-terrorism and riot control, and in harsh environments like mining, coal mining, and excavation. This can help prevent unexpected injuries. As we all know, helmets mainly come in two types: full-face and half-face. Full-face helmets feature a chin guard that hugs the wearer's chin, providing excellent head protection. Half-face helmets, on the other hand, lack a chin guard, but because the chin guard doesn't restrict the wearer's mouth and nose, they can be used for activities like drinking water and talking without removing the helmet, making them more user-friendly.

[0003] There is no doubt that for helmet wearers, full-face helmets have sufficient safety protection, but their user-friendliness is relatively poor. Although half-face helmets are more user-friendly, their safety protection is lacking. In order to combine the advantages of full-face helmets and half-face helmets and effectively eliminate their respective disadvantages, a helmet with a variable chin guard structure has emerged. Its feature is that the chin guard of the helmet can be converted between a full-face structure position and a half-face structure position according to demand, such as Spanish patent application ES2329494T3 and Chinese patent applications CN105901820A, CN109875177A and CN114158814A filed by the applicant of the present patent, etc. The helmets involved in the above patent applications belong to the category of helmets with variable chin guard structures.

[0004] However, existing helmets with variable chin guard structures generally have a common problem, that is, the two fork handles of the chin guard adopt a structural form that is convex relative to the helmet shell body. Specifically, when the helmet is in the full helmet position, the main structure of the chin guard fork handle must be arranged to protrude from the helmet shell body. Only in this way can the chin guard be free from the constraints of the helmet shell body when converted to a half helmet structure helmet and can move in position and posture relative to the helmet shell body. Obviously, this type of variable chin guard helmet with a convex layout fork handle in the full-face helmet position has several shortcomings, specifically: 1) The convex layout fork handle will lead to the deterioration of the aerodynamic performance of the helmet, because the chin guard fork handle protruding from the helmet shell body will inevitably generate turbulence and additional wind resistance during the wearer's riding process, which will not only cause unnecessary resistance, but also have a negative impact on the wearing reliability of the helmet; 2) The convex layout fork handle will lead to worse comfort in wearing the helmet, also due to the turbulence caused by the chin guard fork handle protruding from the helmet shell body, it will produce uncomfortable airflow whistling sound when the wearer rides, in other words, it has a negative impact on the wearer's wearing comfort; 3) The convex layout fork handle will also cause the volume of the helmet to increase, which is obvious. Due to the relatively larger volume of the helmet, on the one hand, the weight of the helmet becomes heavier and the load burden on the wearer increases, resulting in the wearer being easily fatigued. On the other hand, due to the increased volume of the helmet, its storage space becomes larger, which is obviously disadvantageous for warehousing, transportation and storage. 4) The convex layout of the fork handle has another defect, which is that it will cause the structural load-bearing capacity of the helmet to become weaker. The reason is that when the helmet is subjected to a strong external collision impact, the impact force generated by the jaw guard cannot be directly transmitted to the helmet shell body by the fork handle body, but is indirectly and dislocatedly transmitted to the helmet shell body through the connecting parts, resulting in poor impact resistance of the jaw guard, and thus there are certain safety hazards.

[0005] In summary, while existing helmets with variable chin guards can transition between full-face and half-face configurations, their convex grips lead to deficiencies in reliability, comfort, safety, and storage. In short, existing helmets with variable chin guards still have room for further improvement and enhancement. Summary of the Invention

[0006] In response to the above-mentioned problems existing in current helmets with variable jaw guard structures, the present invention provides a helmet with a jaw guard that can rotate on a fixed axis to change its position and posture. The purpose is: compared with the existing technology of helmets with variable jaw guard structures, it improves the structure of the jaw guard fork handle and its driving mechanism, so that the jaw guard can be converted between the full helmet structure and the half helmet structure in position and posture while effectively improving the reliability, comfort, safety and storage of the helmet.

[0007] The purpose of the present invention is achieved as follows: a fixed-axis rotating variable jaw guard helmet, which includes a helmet shell body, a jaw guard, two bases and a shield, the helmet shell body has a symmetrical plane, the two bases are separated by the symmetrical plane and are respectively arranged on the two side surfaces of the helmet shell body, and the two bases are fastened to the helmet shell body or the two bases and the helmet shell body are made of an integral structure, the jaw guard has two fork handles, and the two fork handles are respectively arranged on both sides of the helmet shell body; it is characterized in that: two first restraining bodies are provided, and the two first restraining bodies Separated by the symmetry plane and arranged on both sides of the helmet shell body, the first constraint body is fastened to the base and / or the helmet shell body, or the first constraint body and the base and / or the helmet shell body are made as an integral structure; a second constraint body is provided on each of the fork handles, and the second constraint body is fastened to the fork handle or the second constraint body and the fork handle are made as an integral structure; the first constraint body and the second constraint body arranged on the same side of the helmet shell body together constitute at least one pair of motion matching pairs, and these motion matching pairs have a fixed axis that is stationary relative to the helmet shell body. line, and in each pair of kinematic matching pairs, the first constraint body and the second constraint body participating in the contact structure of the kinematic matching pair are composed of a collection of geometric elements distributed at equal distances from the fixed axis, the second constraint body can perform rotational motion, and under the constraint of the first constraint body, the rotational motion is manifested as a fixed-axis rotation around the fixed axis; in addition, a displacement obtaining mechanism is provided, which can generate an opening displacement movement away from the symmetric plane of the helmet shell body in response to the chin guard being opened and separated from its full-face helmet structure position, and can generate a closing displacement movement close to the symmetric plane of the helmet shell body in response to the chin guard being returned to its full-face helmet structure position, and at the same time, the first constraint body forms an axial constraint behavior on the second constraint body during its opening displacement movement and during its closing displacement movement. The characteristic of this axial constraint behavior is that it causes the opening displacement movement and the closing displacement movement of the second constraint body to be manifested as a linear displacement along the direction of the fixed axis of the kinematic matching pair.

[0008] Furthermore, the above-mentioned displacement obtaining mechanism is or includes at least one of the following three displacement obtaining mechanisms a), b), and c):

[0009] a) The first constraint body and the second constraint body are arranged on the same side of the helmet shell body in response to each other, and a first hole is provided on the first constraint body, the base or the helmet shell body, and a push rod corresponding to the first hole is provided on the second constraint body or / and the fork; or / and, the first constraint body and the second constraint body are arranged on the same side of the helmet shell body in response to each other, and a first hole is provided on the second constraint body or / and the fork, and a push rod corresponding to the first hole is provided on the first constraint body, the base or the helmet shell body; the first hole or / and the push rod include at least one first inclined surface in the shape of a slope relative to the symmetry surface of the helmet shell body, and in response to the chin guard being opened, separated from or returned to its full helmet structure position, the push rod and the first hole are in contact at the first inclined surface, and through this contact behavior, the second constraint body can generate a displacement action away from or close to the symmetry surface of the helmet shell body, thereby forming a displacement acquisition mechanism;

[0010] b) A first restraining body and a second restraining body are arranged on the same side of the helmet shell body in response to the first restraining body and the second restraining body, a tension column is provided on the second restraining body and / or the fork handle, and a first limiting structure is provided on the tension column. In addition, a second limiting structure is provided on the first restraining body, the base or the helmet shell body; the first limiting structure and / or the second limiting structure include a first inclined surface, and in response to the chin guard being opened and separated from, or returning to its full-face helmet structure position, the first limiting structure and the second limiting structure are in contact at the first inclined surface included therein, and through this contact, the second restraining body can generate a displacement movement away from or close to the symmetry plane of the helmet shell body, thereby forming a displacement acquisition mechanism;

[0011] c) The first constraint body and the second constraint body are arranged on the same side of the helmet shell body in response to each other, and a groove-shaped track groove is provided on the first constraint body, the base or the helmet shell body, and a load-bearing pin is provided on the second constraint body and / or the fork handle, and the load-bearing pin is inserted into the track groove and constrained by the track groove; or, the first constraint body and the second constraint body are arranged on the same side of the helmet shell body in response to each other, a groove-shaped track groove is provided on the second constraint body and / or the fork handle, and a load-bearing pin is provided on the first constraint body, the base or the helmet shell body, and the load-bearing pin is inserted into the track groove and constrained by the track groove; in addition, a first inclined surface is opened in the track groove, and in response to the process stage of the chin guard being opened and separated from or returned to the full helmet structure position, the load-bearing pin and the track groove have a contact behavior at the first inclined surface, and through this contact behavior, the second constraint body can generate a displacement action away from or close to the symmetry plane of the helmet shell body, thereby forming a displacement acquisition mechanism.

[0012] Furthermore, the above-mentioned second constraint body and / or fork handle is provided with a load-bearing member, which is fastened to or made as an integral structure on the second constraint body and / or fork handle; an energy storage spring is provided between the load-bearing member and the first constraint body, or between the load-bearing member and the base support, or between the load-bearing member and the helmet shell body, one end of the energy storage spring rests on the load-bearing member, and the other end of the energy storage spring rests on the first constraint body, the base support or the helmet shell body.

[0013] Furthermore, the first constraint body is provided with and only provided with a first hole groove, and the second constraint body is provided with and only provided with a push rod corresponding to the first hole groove; or the second constraint body is provided with and only provided with a first hole groove, and the first constraint body is provided with and only provided with a push rod corresponding to the first hole groove; the first hole grooves and push rods arranged on the same side of the helmet shell body are all greater than or equal to three in number, and these first hole grooves and push rods are paired one by one, and each pair of first hole grooves and push rods has an equivalent radius with the fixed axis of the motion matching pair as the measurement starting point, and the first slope with a larger equivalent radius has a smaller value of the equivalent slope.

[0014] Furthermore, for all the above-mentioned paired first slots and push rods, the equivalent radius of the first inclined surface of each pair is not equal to each other, and when the second constraint body rotates around the fixed axis of its motion matching pair, the contact behavior of each paired push rod and the first slot at the equivalent radius of their respective first inclined surfaces all presents a timing pattern of synchronous contact and synchronous separation.

[0015] Furthermore, the first constraint body is provided with a second hole slot, and the number of the second hole slots is consistent with the number of the struts provided only on the second constraint body; or the second constraint body is provided with a second hole slot, and the number of the second hole slots is consistent with the number of the struts provided only on the first constraint body; the second hole slots and the struts are paired in a one-to-one correspondence, and the paired second hole slots and the struts include a second inclined surface that is sloped relative to the symmetrical surface of the helmet shell body; in response to the process stage of the jaw guard flipping out of or approaching to sit in its half-helmet structure position, the paired struts and the second hole slots have mutual contact at their second inclined surfaces, and these contact behaviors can prompt the second constraint body to produce a displacement action close to or away from the symmetrical surface of the helmet shell body.

[0016] Furthermore, a buckle is provided on the above-mentioned first restraint body, base or helmet shell body, and a tongue corresponding to the buckle is provided on the load-bearing member. When the jaw guard is in the full helmet structure position or / and the half helmet structure position and is observed along the direction of the fixed axis of the motion matching pair toward the symmetry plane of the helmet shell body: the buckle is located farther away from the symmetry plane of the helmet shell body than the tongue, and when they are projected onto the symmetry plane of the helmet shell body, the projection of at least one buckle intersects with the projection of the tongue.

[0017] Furthermore, there are three first slots arranged on the same side of the helmet shell body. These three first slots all include a first inclined surface. Starting from the slope vertices corresponding to the equivalent radius of each first inclined surface, perpendicular lines are drawn to the fixed axis of the kinematic fit pair, and these perpendicular lines are projected onto the symmetry plane of the helmet shell body. The minimum angles formed between the projections of the three perpendicular lines obtained on the symmetry plane are no less than 90°, and the sum of the three minimum angles formed between the projections of the three perpendicular lines obtained is always maintained at 360°.

[0018] Furthermore, the energy storage spring is a conical spring, and the conical energy storage spring and the fixed axis of the kinematic fitting pair are coaxially arranged.

[0019] Furthermore, the above-mentioned load-bearing member and / or the connecting accessories of the load-bearing member are made of magnetically attractive materials or are magnets, and magnets or magnetically attractive parts are provided on the helmet shell body, the base or the first constraint body to correspond to them and together form a magnetic pair.

[0020] The above-mentioned shield includes two supporting sides, which are separated by the symmetrical plane and are located on both sides of the helmet shell body; at least one base includes an outer cover and a bottom cover, and a driving gear that can rotate on a fixed axis, a rack engaged with the driving gear, and a power spring that can drive the driving gear to rotate are equipped on this base or the helmet shell body. The rack is connected to the supporting sides of the shield, and an arc-shaped outer guide groove is provided on the outer cover and / or the helmet shell body, and an arc-shaped inner guide groove is provided on the bottom cover and / or the helmet shell body. The outer guide groove and the inner guide groove together constitute a constraint guide rail, and the constraint guide rail is used to constrain the position and posture of the rack.

[0021] Furthermore, the above-mentioned base and / or helmet shell body is provided with a locking tooth mechanism, which includes an external tooth arranged on the rack, an internal tooth mounted on the base or the helmet shell body and a locking tooth spring. The body of the internal tooth is constrained by the base and / or the helmet shell body and under its constraint, the movement of the internal tooth is expressed in the form of linear displacement, or in the form of swinging displacement, or in the form of a composite displacement including linear displacement and swinging displacement, wherein the elastic force of the locking tooth spring always tends to force the internal tooth to press against the external tooth.

[0022] Furthermore, the above-mentioned second constraint body is provided with a first card slot that responds to the jaw guard being in the full helmet structure position, and the second constraint body is provided with a second card slot that responds to the jaw guard being in the half helmet structure position; an insertion card including an inclined thrust structure is equipped on the base support and / or the helmet shell body, and the insertion card is in contact with the second constraint body; in addition, at least one thrust spring is also provided on the base support and / or the helmet shell body, one end of the thrust spring is in contact with the body of the insertion card, and the other end of the thrust spring is in contact with the base support or the helmet shell body, and the elastic force of the thrust spring always forces the insertion card to be in contact with the second constraint body; when the jaw guard rotates and drives the second constraint body to rotate so that the first card slot or the second card slot thereon comes into contact with the inclined structure of the insertion card, the body of the insertion card will produce a displacement action close to or away from the fixed axis of the motion matching pair.

[0023] Furthermore, an internal snap structure is provided on the body of the above-mentioned plug-in card, and an external snap structure is provided on the body of the internal snap tooth. When the plug-in card makes a displacement action away from the fixed axis of the motion matching pair, the internal snap structure of the plug-in card body can touch the external snap structure on the body of the internal snap tooth and drive the internal snap tooth to produce an unlocking displacement action to disengage from the external snap tooth.

[0024] Furthermore, a sloped top-opening structure is provided on the body of the above-mentioned plug-in card or the body of the inner card tooth, and a lifting slope corresponding to the top-opening structure is provided on the body of the rack. When the shield is in the buckled state, if the plug-in card makes a displacement action away from the fixed axis of the motion matching pair, the top-opening structure can touch the lifting slope and the contact behavior can generate a lifting displacement action that causes the shield to be opened.

[0025] Furthermore, the outer latch includes two concave tooth grooves and the inner latch includes at least one convex protruding tooth, or the inner latch includes two concave tooth grooves and the outer latch includes at least one convex protruding tooth, and when these protruding teeth and the tooth grooves are engaged, the locking tooth mechanism is in a locking tooth state, wherein in the locking tooth mechanism, when the locking tooth state stage occurs: in the case where the outer latch includes two concave tooth grooves and the inner latch includes at least one convex protruding tooth, when a protruding tooth appears in the tooth groove farther away from the jaw guard fork handle and engages with it, The lower edge of the guard is completely fastened to the jaw guard, and when there is no protruding tooth in the tooth groove farther away from the jaw guard fork handle to engage with it, a breathable gap appears between the lower edge of the guard and the jaw guard; in the case where the inner teeth include two concave tooth grooves and the outer teeth include at least one convex tooth, when there is a protruding tooth in the tooth groove closer to the jaw guard fork handle to engage with it, the lower edge of the guard is completely fastened to the jaw guard, and when there is no protruding tooth in the tooth groove closer to the jaw guard fork handle to engage with it, a breathable gap appears between the lower edge of the guard and the jaw guard.

[0026] Furthermore, the above-mentioned card insertion has an arc-shaped stabilizing structure, which is arranged at the top end of the card insertion and has an inverse bow layout with the arc opening opening outward. When the card insertion is completely out of the first card slot and the second card slot on the second constraint body, the arc surface of the inverse bow layout of the stabilizing structure is in contact with the second constraint body.

[0027] The above-mentioned second constraint body is provided with a passive tooth, and a driving gear that can rotate about a fixed axis is provided on the base support, the helmet shell body or the first constraint body, and the driving gear maintains an engaged state with the passive tooth on the second constraint body; in addition, a torsion spring is provided, one end of the torsion spring rests on the active tooth, and the other end of the torsion spring rests on the base support, the helmet shell body or the first constraint body. The active gear can generate fixed-axis rotation under the action of the torsion spring, and the rotation of the active gear drives the second constraint body to rotate around the fixed axis of the motion matching pair through the passive tooth.

[0028] Furthermore, the driving gear has only one special-shaped tooth, the tooth width of which is greater than the tooth width of the other normal teeth of the driving gear. All the teeth of the driving gear, including the special-shaped tooth, are distributed in a complete 360° circumference, and when the chin guard is flipped from the full-face helmet structure position to the half-face helmet structure position, the driving gear rotates one full circle.

[0029] A shield locking and unlocking mechanism is provided at the lower edge of the above-mentioned shield and on the main body of the chin guard, and the shield locking and unlocking mechanism includes an inner buckle structure provided at the lower edge of the shield and an outer buckle structure provided on the main body of the chin guard, the inner buckle structure includes a locking structure, and the outer buckle structure includes a bougie that can be forced to give way and a lock hook provided on the bougie; in addition, the shield locking and unlocking mechanism also includes a first unlocking key and / or a second unlocking key, the first unlocking key and the second unlocking key are arranged on the main body of the chin guard and they can both serve as actuating members for unlocking the shield, wherein the first unlocking key is arranged adjacent to the bougie and can touch the bougie during its actuation, and the second unlocking key is arranged at the lower edge of the chin guard, and the second unlocking key can unlock the chin guard in the position of the full helmet structure, And the bougie can be controlled in linkage during the actuation of the second unlocking button; when the chin guard is in the full-helmet structure position and the shield is completely buckled on the chin guard, the shield locking and unlocking mechanism can have three working conditions: a) when the first unlocking button and the second unlocking button are not touched, the lock hook on the bougie is in the original position, and the lock hook in the original position can hook into the locking structure of the inner buckle structure to thereby lock the shield; b) when the first unlocking button is controlled and during its actuation, the first unlocking button can touch the bougie and, through the touching behavior, can cause the lock hook of the bougie to leave its original position to thereby unlock the shield; c) when the second unlocking button is controlled and during its actuation, the second unlocking button can drive the bougie and, through the driving behavior, can cause the lock hook of the bougie to leave its original position to thereby unlock the shield.

[0030] The present invention discloses a fixed-axis rotating variable chin guard helmet, which adopts a structural scheme of arranging a first constraint body and a second constraint body on a base, and utilizing them to form a kinematic matching pair including a stationary fixed axis relative to a helmet shell body. The most significant feature of the helmet helmet is that under the constraint of the first constraint body, the second constraint body can not only rotate around the fixed axis, but also make a displacement movement away from or close to the symmetry plane of the helmet shell body along the fixed axis, thereby enabling the body of the chin guard fork handle to produce an opening and closing displacement movement relative to the symmetry plane of the helmet shell body. In other words, the chin guard can be displaced away from the symmetry plane of the helmet shell body during the process of being lifted up and separated from its full-face helmet structure position, and can be displaced close to the symmetry plane of the helmet shell body during the process of returning to its full-face helmet structure position. Compared with conventional helmets with variable chin guard structures, the variable chin guard helmet of the present invention, on the one hand, can extend its fork outward when the chin guard is flipped to avoid being restrained by the helmet shell and the shield, thereby not affecting its conversion between the full-face helmet structure position and the half-helmet structure position. On the other hand, when the chin guard is in the full-face helmet structure position, its fork can be in a retracted and collapsed structure relative to the helmet shell. This brings the following benefits: first, in the full-face helmet structure, which is commonly worn while driving, the chin guard fork can become a seamless whole with the helmet shell, eliminating the abrupt protruding fork layout of the conventional variable chin guard structure. Therefore, the airflow whistling sound caused by the fork protruding too much from the helmet surface during driving can be effectively eliminated, thereby improving the wearing comfort of the helmet and reducing the size of the helmet, thereby improving its storage capacity. Secondly, the chin guard in the retracted structure layout in the full-face helmet structure position can directly abut the helmet shell. Therefore, when the chin guard is subjected to impact or collision, the force applied to the chin guard can be directly transmitted to the helmet shell, which will inevitably greatly improve the safety and reliability of the helmet. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is an axonometric view of a fixed-axis rotating variable jaw guard helmet of the present invention, with the jaw guard in a full-face helmet structure position and the shield in a completely buckled-down state;

[0032] Figure 2 yes Figure 1 A side view of a fixed-axis rotating variable jaw guard helmet according to the present invention in the illustrated state;

[0033] Figure 3 yes Figure 1 A front view of a fixed-axis rotating variable jaw guard helmet according to the present invention in the illustrated state;

[0034] Figure 4 This is an axonometric view of a fixed-axis rotating variable jaw guard helmet of the present invention, with the jaw guard in a full-face helmet structure position and the shield in a fully opened state;

[0035] Figure 5 yes Figure 4 A side view of a fixed-axis rotating variable jaw guard helmet according to the present invention in the illustrated state;

[0036] Figure 6 yes Figure 4 A front view of a fixed-axis rotating variable jaw guard helmet according to the present invention in the illustrated state;

[0037] Figure 7 This is an axonometric view of a fixed-axis rotating variable jaw guard helmet of the present invention, with the jaw guard in a half-helmet structure position and the shield in a completely buckled-down state;

[0038] Figure 8 yes Figure 7 A side view of a fixed-axis rotating variable jaw guard helmet according to the present invention in the illustrated state;

[0039] Figure 9 yes Figure 7 A front view of a fixed-axis rotating variable jaw guard helmet according to the present invention in the illustrated state;

[0040] Figure 10 This is an axonometric view of a fixed-axis rotating variable jaw guard helmet of the present invention, with the jaw guard in a half-helmet structure position and the shield in a fully opened state;

[0041] Figure 11 yes Figure 10 A side view of a fixed-axis rotating variable jaw guard helmet according to the present invention in the illustrated state;

[0042] Figure 12 yes Figure 10 A front view of a fixed-axis rotating variable jaw guard helmet according to the present invention in the illustrated state;

[0043] Figure 13 This is an exploded diagram of the assembly of the main parts of a fixed-axis rotating variable jaw guard helmet of the present invention;

[0044] Figure 14 This is a schematic diagram of the installation layout of the base support and the first constraint body of a fixed-axis rotating variable jaw guard helmet of the present invention;

[0045] Figure 15 This is a schematic plan view of the installation layout of the base support and the first constraint body of a fixed-axis rotating variable jaw guard helmet of the present invention;

[0046] Figure 16 This is a schematic diagram of the layout of the chin guard fork and the second restraining body of a fixed-axis rotating variable chin guard helmet of the present invention;

[0047] Figure 17 yes Figure 16 A schematic cross-sectional view of the jaw guard and its fork handle shown;

[0048] Figure 18 A side view of a fixed-axis rotating variable chin guard helmet according to the present invention, showing the behavior of the chin guard during the process of opening and separating from the full-face helmet structure;

[0049] Figure 19 It is a front view schematic diagram of a fixed-axis rotating variable chin guard helmet of the present invention, showing the behavior of the fork handle during the process of the chin guard being opened and separated from the full-face helmet structure;

[0050] Figure 20 This is a schematic diagram of the behavior of the main parts of a displacement obtaining mechanism embodiment of a fixed-axis rotating variable jaw guard helmet according to the present invention when viewed in a circular section along an equivalent radius;

[0051] Figure 21 This is a schematic diagram of the behavior of the main parts of another embodiment of the displacement obtaining mechanism of the fixed-axis rotating variable jaw guard helmet of the present invention when viewed in a circumferentially expanded section along the equivalent radius;

[0052] Figure 22 This is a schematic diagram of the behavior of the main parts of another embodiment of the displacement obtaining mechanism of the fixed-axis rotating variable jaw guard helmet of the present invention when viewed in a circular section along the equivalent radius;

[0053] Figure 23 This is a schematic diagram of the structural layout of the fixed-axis rotating variable jaw guard helmet of the present invention, which has a load-bearing member and an energy storage spring component, and the jaw guard fork is in a retracted state;

[0054] Figure 24 This is a schematic diagram of the structural layout of the fixed-axis rotating variable jaw guard helmet of the present invention, which has a load-bearing member and an energy storage spring component, and the jaw guard fork is in an outwardly extended state;

[0055] Figure 25 This is a state diagram of the process when the jaw guard of the fixed-axis rotating variable jaw guard helmet of the present invention is converted from a full-helmet structure position to a half-helmet structure position;

[0056] Figure 26 This is a state diagram of the process when the jaw guard of the fixed-axis rotating variable jaw guard helmet of the present invention is converted from a half-helmet structure position to a full-helmet structure position;

[0057] Figure 27 This is an isometric diagram of the state of the locking gear mechanism of the fixed-axis rotating variable jaw guard helmet of the present invention when the shield is in a fully engaged state;

[0058] Figure 28 yes Figure 27A front view of the working posture of the locking gear mechanism of the shield in the illustrated state;

[0059] Figure 29 yes Figure 27 A partial axonometric view of the working posture of the locking gear mechanism of the shield in the illustrated state;

[0060] Figure 30 This is an isometric diagram of the state of the locking gear mechanism of the fixed-axis rotating variable jaw guard helmet of the present invention when the shield is in a slightly open state;

[0061] Figure 31 yes Figure 30 A front view of the working posture of the locking gear mechanism of the shield in the illustrated state;

[0062] Figure 32 yes Figure 30 A partial axonometric view of the working posture of the locking gear mechanism of the shield in the illustrated state;

[0063] Figure 33 This is an isometric diagram of the state of the locking gear mechanism of the fixed-axis rotating variable jaw guard helmet of the present invention when the shield is in a fully opened state;

[0064] Figure 34 yes Figure 33 A front view of the working posture of the locking gear mechanism of the shield in the illustrated state;

[0065] Figure 35 yes Figure 33 A partial axonometric view of the working posture of the locking gear mechanism of the shield in the illustrated state;

[0066] Figure 36 This is an assembly diagram and exploded view of the fixed-axis rotating variable jaw guard helmet of the present invention, including the inserting card and the inner card teeth;

[0067] Figure 37 This is a schematic diagram of a fixed-axis rotating variable jaw guard helmet according to the present invention, in which the lifting structure on the inserting card lifts up the lifting inclined surface on the rack to cause the lower edge of the shield to separate from the jaw guard;

[0068] Figure 38 This is a side view of the fixed-axis rotating variable jaw guard helmet of the present invention, with the shield in a slightly open state;

[0069] Figure 39 This is a front view of the fixed-axis rotating variable jaw guard helmet of the present invention, with the shield in a slightly open state;

[0070] Figure 40 Schematic diagram of a fixed-axis rotating variable jaw guard helmet provided with an automatic pop-up jaw guard device according to the present invention;

[0071] Figure 41This is an axonometric diagram of the core components of the shield locking and unlocking mechanism of the fixed-axis rotating variable jaw guard helmet of the present invention;

[0072] Figure 42 The present invention is a schematic diagram describing three working conditions of the shield locking and unlocking mechanism of the fixed-axis rotating variable jaw guard helmet. DETAILED DESCRIPTION

[0073] The present invention will be further described below with reference to specific embodiments. Figure 1 —42:

[0074] A fixed axis rotating variable jaw guard helmet, comprising a helmet shell body 1, a jaw guard 2, two bottom brackets 3 and a shield 4 (see Figure 13 ), wherein the helmet shell body 1 has a symmetry plane P, the two bottom brackets 3 are separated by the symmetry plane P and are respectively placed on the two side surfaces of the helmet shell body 1, and the two bottom brackets 3 are fastened to the helmet shell body 1 or the two bottom brackets 3 and the helmet shell body 1 are made of an integral structure, Figure 14 and Figure 15 The embodiment shown is a case where the base 3 is fastened and connected to the helmet shell body 1 by screws. When the base 3 and the helmet shell body 1 are made into an integral structure, the base 3 can be regarded as a part of the helmet shell body 1; the jaw guard 2 has two fork handles 2a, and the two fork handles 2a are respectively placed on both sides of the helmet shell body 1 (see Figure 3 、 Figure 6 、 Figure 9 and Figure 12 The main structure of the shield 4 is made of a transparent material that does not hinder the helmet wearer's observation. The function of the shield 4 is to prevent wind, sand and rain from entering the interior of the helmet to avoid negatively affecting the helmet wearer's driving experience. It should be noted that the position of the shield 4 in the present invention can be selected according to the needs of the user, and the buckle and flip operation can be completed manually. Figures 1 to 3 The situation shown is when the chin guard 2 is in the full-face helmet structure position and the shield 4 is in a fully engaged state. At this time, the shield 4 can play the best role in protecting against wind, sand and rain. Figures 7 to 9 The situation shown is that the chin guard 2 is in the half-helmet structure position and the shield 4 is in a fully buckled state. In this case, the shield 4 can prevent wind, sand, rain, etc. from blowing directly into the eyes and thus does not affect the wearer's vision; Figures 4 to 6 、 Figures 10 to 12 The shield 4 is shown in a fully opened state, which is suitable for use in scenes with no wind, sand or rain or with little wind, sand or rain. Here, the phrase "the two forks 2a are placed on both sides of the helmet shell body 1" means that the two forks 2a are separated by the symmetry plane P of the helmet shell body 1 and are placed on both sides of the helmet shell body 1 (see Figure 3 、 Figure 6 、 Figure 9 and Figure 12 ), wherein the symmetry plane P of the present invention refers to such a plane (see Figure 1 、 Figure 4 、 Figure 7 and Figure 10 ): When the wearer wears the helmet normally, the symmetry plane P passes through the wearer's mouth, nose and top of the skull and separates the wearer's eyes and ears on both sides of it, that is, the symmetry plane P is an imaginary plane with the property of dividing the helmet shell body 1 in the middle, and being arranged on the same side of the helmet shell body 1 also means being arranged on the same side of the symmetry plane P. At the same time, there is an intersection line S between the symmetry plane P and the outermost surface of the helmet and the surfaces of some parts and accessories; in addition, the helmet shell body 1 mentioned in the present invention is a general term, which includes both the main body of the helmet shell cover and other various spare parts such as windshields, covers, hangers, seals, fasteners and other functional parts or decorative parts that are fastened to or attached to the shell cover main body. It is worth noting that the best layout of the base 3 in the present invention is to be arranged on the side of the helmet shell body 1 close to or near the ears of the helmet wearer (such as Figures 1 to 15 As shown in the figure, the preferred layout of the jaw guard 2 is that the main bodies of the two forks 2a are placed on both sides of the symmetry plane P of the helmet shell body 1 and are arranged in correspondence with the position of the base 3; it is also worth noting that the base 3 of the present invention can be a complete independent part (not shown in the figure), and in particular, the base 3 can also be a component composed of various parts or assembled together. Figure 13 The base 3 in the illustrated embodiment is composed of multiple parts including the outer cover 3a and the bottom cover 3b. The present invention has the following three major features in terms of structural design and layout, movement realization and function achievement:

[0075] 1) First, a major feature of the present invention is reflected in its structural setting. There are two first restraining bodies 5, which are separated by the symmetry plane P and are placed on both sides of the helmet shell body 1 (see Figure 13), the first constraint body 5 is fastened to the base 3 and / or the helmet shell body 1, or the first constraint body 5 and the base 3 and / or the helmet shell body 1 are made as an integral structure, that is, the first constraint body 5 can be fastened to the base 3 or the helmet shell body 1 alone, or the first constraint body 5 can be fastened to the base 3 and the helmet shell body 1 at the same time. In addition, the first constraint body 5 can be made as an integral structure with the base 3 or the helmet shell body 1 alone, or the first constraint body 5 can be made as an integral structure with the base 3 and the helmet shell body 1 at the same time; here, when the first constraint body 5 and the base 3 are made as an integral structure, the first constraint body 5 can be regarded as a part of the base 3, especially when the base 3 includes multiple parts, if the first constraint body 5 and any one of the parts are made as an integral structure, it is also regarded as the first constraint body 5 and the base 3 are made as an integral structure, and the first constraint body 5 can be regarded as a part of the base 3 ( Figure 13 In the illustrated case, the first restraint 5 and the bottom cover 3b of the base 3 are examples of being manufactured as an integral structure); similarly, when the first restraint 5 and the helmet shell body 1 are manufactured as an integral structure, the first restraint 5 can also be regarded as a part of the helmet shell body 1. In addition, the present invention provides a second restraint 6 on each of the fork handles 2a, and the second restraint 6 is fastened to the fork handle 2a (not shown in the figure) or the second restraint 6 is manufactured as an integral structure with the fork handle 2a (as shown in the figure). Figure 13 、 Figure 16 and Figure 17 As shown), when the second constraint body 6 and the fork handle 2a are made into an integral structure, the second constraint body 6 can be regarded as a part of the fork handle 2a.

[0076] 2) Another major feature of the present invention is its ability to constrain and obtain circumferential motion. The first constraint body 5 and the second constraint body 6 arranged on the same side of the helmet shell body 1 together form at least one pair of kinematic matching pairs. These kinematic matching pairs share a fixed axis O1 that is stationary relative to the helmet shell body 1 (see Figure 13 、 Figure 23 and Figure 24 ), and in each pair of kinematic matching pairs, the first constraint body 5 and the second constraint body 6 participate in forming the contact structure A of the kinematic matching pair, which is composed of a set of geometric elements that are equidistantly distributed from the fixed axis O1 (such as Figure 23 and Figure 24As shown), the second constraint body 6 can perform rotational motion and under the constraint of the first constraint body 5, the rotational motion is manifested as a fixed-axis rotation around the fixed axis O1; in other words, the first constraint body 5 and the second constraint body 6 arranged on the same side of the helmet shell body 1 can have multiple pairs of motion matching pairs at the same time, and each pair of these motion matching pairs is composed of the contact structure A of the first constraint body 5 and the second constraint body 6, and the contact structure A of each pair is coaxially arranged. From the perspective of simplifying the structure and reducing interference, it is undoubtedly a better solution to let the first constraint body 5 and the second constraint body 6 arranged on the same side of the helmet shell body 1 have only one pair of motion matching pairs; specifically, the main structure of the contact structure A can be a discrete geometric element, such as scattered points, scattered and small contact surfaces, etc., or it can be a continuous geometric element, such as a contact surface with a larger area, a longer contact line or annular surface, etc. In particular, the best form of the contact structure A is a continuous and relatively complete cylindrical surface or circular hole surface (such as Figure 13 As shown); It is not difficult to find that in the same pair of kinematic matching pairs, the contact structure A of the second constraint body 6 must be affected and constrained by the contact structure A of the first constraint body 5 (this constraint is just like the matching of the shaft and the hole). Of course, other components are allowed to participate in the auxiliary constraint of the rotational motion of the second constraint body 6 (not shown in the figure); Here, the cylindrical surfaces where the contact structures A of the first constraint body 5 and the second constraint body 6 of each pair of kinematic matching pairs are located can overlap to form a cylindrical surface, but they are also allowed to have a certain matching clearance and the situation where the cylindrical surfaces are inconsistent due to matching needs, assembly needs and deformation adaptation needs are allowed ( Figure 23 and Figure 24The situation shown is an example in which a fitting gap is left between the contact structure A of the first constraint body 5 and the contact structure A of the second constraint body 6). At the same time, it is also allowed that the cylindrical surfaces on which the contact structures A of the first constraint body 5 and the second constraint body 6 are distributed have certain errors such as cylindricity, roundness or circular runout. As long as these errors do not affect the posture (that is, position and posture, the same below) conversion of the jaw guard 2 and the normal use of the helmet, they are regarded as within the allowable engineering error range and can therefore be ignored. It should be noted that the jaw guard 2 in the present invention can change its position and posture, and therefore the second constraint body 6 is a moving part that can change its position and posture relative to the helmet shell body 1, and the first constraint body 5 is a static part that does not move relative to the helmet shell body 1. Therefore, as the second constraint body 6 in the same motion matching pair, its contact structure A must be restricted by the contact structure A of the first constraint body 5. In view of the geometric properties of the contact structure A in the present invention that is distributed on a cylindrical surface (or a circular hole surface) with the fixed axis O1 as the axis, the part of the rotational movement in the movement of the second constraint body 6 is manifested as a fixed-axis rotation around the fixed axis O1. Therefore, it can be said that the fixed-axis rotation of the second constraint body 6 around the fixed axis O1 of the motion matching pair is completed under the constraint dominated by the first constraint body 5. Regarding the layout of the fixed axis O1, the present invention includes but is not limited to the following two preferred layout situations: ① The fixed axes O1 of the motion matching pairs placed on both sides of the helmet shell body 1 are coaxially arranged, and the fixed axis O1 is perpendicular to the symmetry plane P of the helmet shell body 1 (such as Figure 3 、 Figure 6 、 Figure 9 、 Figure 12 、 Figure 23 and Figure 24 ② The kinematic matching pairs disposed on both sides of the helmet shell body 1 have their fixed axes O1 in the same plane and are mirror-symmetrically distributed about the symmetry plane P, but are non-coaxially arranged (not shown in the figure).

[0077] 3) Another major feature of the present invention is its ability to constrain and obtain axial motion. Specifically, the present invention is provided with a displacement obtaining mechanism. In response to the chin guard 2 being lifted up and out of its full-face helmet structural position, the displacement obtaining mechanism can generate an opening displacement motion that drives the second constraint body 6 away from the symmetry plane P of the helmet shell body 1. Furthermore, in response to the chin guard 2 being returned to its full-face helmet structural position, the displacement obtaining mechanism can generate a closing displacement motion that drives the second constraint body 6 toward the symmetry plane P of the helmet shell body 1. Simultaneously, during both the opening and closing displacement motions of the second constraint body 6, the first constraint body 5 exerts an axial constraint on the second constraint body 6. This axial constraint is characterized in that both the opening and closing displacement motions of the second constraint body 6 are linear displacements along the direction of the motion-matching secondary fixed axis O1. Among them, the displacement obtaining mechanism can adopt a method including mechanism pushing or pressing, spring external support or pulling and contracting, magnetic attraction or repulsion, etc., or a combination of these methods to produce the opening and closing displacement action of the above-mentioned second constraint body 6. Here, the opening and closing displacement movements of the second constraint body 6 away from and close to the symmetry plane P of the helmet shell body 1 can be collectively referred to as "opening and closing displacement movements", and refer to: the second constraint bodies 6 located on both sides of the helmet shell body 1 exhibit opening and closing movements relative to the symmetry plane P, including the opening displacement movement of the second constraint body 6 away from the symmetry plane P of the helmet shell body 1 driven by the displacement obtaining mechanism, and the closing displacement movement of the second constraint body 6 close to the symmetry plane P of the helmet shell body 1 driven by the displacement obtaining mechanism; wherein during the stage of the jaw guard 2 being opened and separated from its full helmet structure position, the axial movement of the second constraint body 6 is an opening displacement movement away from the symmetry plane P of the helmet shell body 1, and during the stage of the jaw guard 2 returning to its full helmet structure position, the movement of the second constraint body 6 is a closing displacement movement close to the symmetry plane P of the helmet shell body 1. Any mechanism or component that can drive the second constraint body 6 to perform an opening displacement action away from the symmetry plane P of the helmet shell body 1 or / and a closing displacement action close to the symmetry plane P of the helmet shell body 1 falls within the scope of the displacement obtaining mechanism described in the present invention; in other words, the functional realization forms of the displacement obtaining mechanism described in the present invention include the single function of completing the opening displacement action, the single function of completing the closing displacement action, and the dual function of completing the opening displacement action and the closing displacement action.The so-called "process stage of responding to the chin guard 2 in opening and separating from its full-helmet structural position" refers to: the chin guard 2 starts to open from the full-helmet structural position until the fork handle 2a of the chin guard 2 completes the opening displacement required to avoid and cross the outer surface of the helmet shell body 1 and the entire shield 4 and move towards the half-helmet structural position. The other "process stage of responding to the chin guard 2 in returning to its full-helmet structural position" refers to: when the chin guard 2 is seated in the full-helmet structural position, its fork handle 2a starts to move from the maximum opening state relative to the helmet shell body 1 to the symmetry plane P of the helmet shell body 1 until the chin guard 2 is completely in place in the full-helmet structural position. The full-helmet structural position refers to the chin guard 2 of the helmet is now in a position that is completely buckled and can embrace the wearer's chin and mouth, and therefore has the best safety protection effect (such as. Figures 1 to 6 The half helmet structure position refers to the position in which the chin guard 2 of the helmet is opened without covering the eyes, nose and mouth of the helmet wearer, and in particular includes the position in which the chin guard 2 is buckled down and abuts against the upper rear surface of the helmet shell body 1 after climbing over the shield 4 (as shown in FIG. Figures 7 to 12As shown), the chin guard 2 in the half-helmet structural position does not hinder the wearer from drinking water, talking, making phone calls and breathing, so the helmet in the half-helmet structural position with the chin guard 2 is very suitable for the wearer as a wearing state choice when taking a break or driving at low speed. In addition, the "simultaneously with the second constraint body 6 during the opening displacement action and the closing displacement action, the first constraint body 5 forms an axial constraint behavior on the second constraint body 6, and the characteristic of this axial constraint behavior is to cause the opening displacement action and the closing displacement action of the second constraint body 6 to be expressed as a linear displacement along the direction of the motion matching pair fixed axis O1" means: when the second constraint body 6 is driven by the displacement obtaining mechanism to make a displacement action away from or close to the symmetry plane P, the contact structure A of the first constraint body 5 is distributed within a length range along the direction of the motion matching pair fixed axis O1, and similarly, the contact structure A of the second constraint body 6 is distributed along the direction of the motion matching pair fixed axis O1. The contact structure A of the first constraint body 5 is also distributed within a certain length range in the direction of the axis O1, so the first constraint body 5 can form an axial constraint on the contact structure A of the second constraint body 6 through its contact structure A, thereby preventing the second constraint body 6 from experiencing unstable conditions such as swaying and shaking relative to the fixed axis O1. Since the contact structure A of the first constraint body 5 is a cylindrical or circular hole-shaped structure with a stationary and certain axial length distribution, and it uses the said motion-matching secondary fixed axis O1 as its axis, under the constraint of the contact structure A of the first constraint body 5, the opening and closing displacement movement of the said second constraint body 6 can only be a linear displacement along the direction of the said motion-matching secondary fixed axis O1, that is, a linear opening and / or closing. It should be pointed out that the "linear displacement" mentioned in the present invention includes and allows for the existence of some non-linear conditions caused by various manufacturing errors, assembly errors, deformation errors and vibration impacts. As long as these errors do not affect the normal use of the chin guard 2 and the helmet, they can be ignored and classified as "linear displacement". In summary, it can be seen that due to the circumferential constraint behavior and axial constraint behavior of the first constraint body 5 on the second constraint body 6, when the jaw guard 2 in the present invention is in the process stage of being opened and separated from the full helmet structure position or buckled and returned to the full helmet structure position, the fork handle 2a of the jaw guard 2 not only makes a fixed-axis rotational motion around the fixed axis O1, but also, in particular, along with this rotational motion, the fork handle 2a also has an axial motion along the direction of the fixed axis O1. In other words, the movement of the fork handle 2a of the jaw guard 2 at this stage is a compound motion.It is particularly important to point out that the present invention achieves the opening and closing displacement movement of the second constraint body 6 relative to the symmetry plane P of the helmet shell body 1, and its realization method mainly relies on the displacement obtaining mechanism. There are many ways to achieve the opening and closing displacement movement of the displacement obtaining mechanism, which include but are not limited to various forms and means such as the pushing and pressing of the mechanism, the external support and tension of the spring, the attraction and repulsion of the magnetic force, etc., and these forms or means can be used alone or in combination. For example, by pushing with a rigid contact mechanism of geometric parts to generate the "opening displacement movement" that drives the second constraint body 6 away from the symmetry plane P of the helmet shell body 1, and still relying on the pressure effect of such a mechanism to generate the second constraint body 6 to move closer to the helmet shell body 1. For example, the rigid contact pushing or pressing of the mechanism is used to generate an "opening displacement action" forcing the second constraint body 6 to move away from the symmetry plane P of the helmet shell body 1, but at the same time, the external supporting effect or the pulling and contracting effect of the spring structure can be used to prompt the second constraint body 6 to generate the so-called "closing displacement action" of approaching the symmetry plane P of the helmet shell body 1; for another example, the external supporting effect or the pulling and contracting effect of the spring structure can be used to force the second constraint body 6 to generate the "opening displacement action" away from the symmetry plane P of the helmet shell body 1, but at the same time, the pushing effect or the pressing effect of the geometric shape parts can be used to prompt the second constraint body 6 to generate the so-called "closing displacement action" of approaching the symmetry plane P of the helmet shell body 1; all these are not listed here one by one. Moreover, the present invention can also adopt two or more ways and means to jointly produce the action of displacement in the same direction. For example, the supporting force generated by the spring can be used in combination with the suction force generated by the magnet to cause the second constraint body 6 to produce the so-called "closing displacement action" of moving closer to the symmetry plane P of the helmet shell body 1, and the supporting force generated by the spring can be used in combination with the pushing force or pressure force of the mechanism to cause the second constraint body 6 to produce the so-called "opening displacement action" away from the symmetry plane P of the helmet shell body 1, etc. Specifically, taking the use of components or mechanisms based on geometric shapes (i.e., geometric structures) to generate the opening and closing movement of the second constraint body 6 as an example, it can adopt but is not limited to geometric constraints such as a swash plate pair, a spiral pair, a cam pair, a lever pair, a hinge pair, a rope constraint, etc., to constitute or combine into a displacement mechanism (not shown in the figure) that can prompt the second constraint body 6 to generate and obtain an opening and closing displacement action, that is, during the process of the jaw guard 2 rotating to change its position and posture, these geometric structures or similar structures are used to derive a force along the direction of the fixed axis O1, and these forces are used to push, press or pull, etc., to force the second constraint body 6 to make a displacement action away from or close to the symmetry plane P of the helmet shell body 1.It is particularly important to note that, as several preferred embodiments for obtaining the opening and closing displacement action of the second constraint body 6, the present invention can particularly adopt or include one or more of the following a), b), and c) displacement obtaining mechanisms to realize the opening and closing displacement action of the second constraint body 6:.

[0078] a) One embodiment of the displacement acquisition mechanism

[0079] In response to the first restraining body 5 and the second restraining body 6 arranged on the same side of the helmet shell body 1, a first hole groove 7a is provided on the first restraining body 5, the base 3 or the helmet shell body 1, and a tappet 8 corresponding to the first hole groove 7a is provided on the second restraining body 6 and / or the fork handle 2a. Figures 13 to 17 The case shown is a case where a first hole groove 7a is provided on the first constraint body 5, and a corresponding push rod 8 is provided on the second constraint body 6 at the same time); or / and, the first constraint body 5 and the second constraint body 6 are arranged on the same side of the helmet shell body 1, and a first hole groove 7a is provided on the second constraint body 6 or / and the fork handle 2a, and a push rod 8 corresponding to the first hole groove 7a is provided on the first constraint body 5, the base 3 or the helmet shell body 1 (not shown in the figure). Here, the first hole groove 7a is in the shape of a countersunk hole or a countersunk groove, and the push rod 8 is in the shape of a convex column or a convex ring (see Figures 13 to 17 ). In the present invention, the first hole slot 7a and / or the support column 8 include at least one first inclined surface 9a in the shape of a slope relative to the symmetry plane P of the helmet shell body 1, in response to the process stage of the jaw guard 2 being opened and separated from or returning to its full helmet structure position, the support column 8 and the first hole slot 7a have a contact behavior at the first inclined surface 9a, and through this contact behavior, the second constraint body 6 can produce a displacement action away from or close to the symmetry plane P of the helmet shell body 1, thereby forming a displacement acquisition mechanism. Among them, the layout of the first inclined surface 9a includes three situations: ① The first inclined surface 9a is provided at the first hole slot 7a and on the support column 8 at the same time (such as Figures 14 to 17② A first inclined surface 9a is provided only at the first hole groove 7a, but a first inclined surface 9a is not provided on the tappet 8 (not shown in the figure); ③ A first inclined surface 9a is provided only on the tappet 8, but a first inclined surface 9a is not provided at the first hole groove 7a (not shown in the figure). For the convenience of description, we agree on some terms related to the first inclined surface 9a: the so-called "slope surface" refers to the main part of the first inclined surface 9a, which is a curved surface spirally surrounding the fixed axis O1. This curved surface can be a single curved surface formed by a complete structural surface, or a combined curved surface composed of multiple structural surfaces. In addition, the curved surface constituting the "slope surface" can also have multiple forms, such as convex slope surfaces, concave slope surfaces, planar slope surfaces, etc. When the pusher 8 (or the first hole groove 7a) and the first inclined surface 9a are in contact on the slope surface, it means that the pusher 8 (when the pusher 8 is a moving part) or the first hole groove 7a (when the first hole groove 7a is a moving part) is in a climbing process or a descending process, and correspondingly, the second constraint body 6 is in a state of being away from or close to the symmetry plane P of the helmet shell body 1; the so-called "top of the slope" refers to an extreme position state of the main body of the first inclined surface 9a (in other words It is said that it is one of the two ends of the slope of the first slope 9a), when the pusher 8 (or the first hole groove 7a) comes into contact with the first slope 9a at this extreme position, it corresponds to that the entire climbing behavior of it on the first slope 9a has just ended or it is just at the starting point of preparing to go downhill, and at this time the second constraint body 6 is at a position that is relatively far away or even the farthest from the symmetry plane P of the helmet shell body 1; the so-called "bottom of the slope" refers to the other extreme position state of the main body of the first slope 9a (in other words, the other end of the two ends of the slope of the first slope 9a), when the pusher 8 (or the first hole groove 7a) comes into contact with the first slope 9a at this extreme position, it corresponds to that the downhill behavior of it on the entire first slope 9a has just ended or it is just preparing to climb, and at this time the second constraint body 6 is at a position that is relatively close to or even the closest to the symmetry plane P of the helmet shell body 1. It should be pointed out that the "top of the slope" and "bottom of the slope" mentioned above are not a point position, but a general term for a collection of many "points" with the same performance behavior characteristics, which are usually displayed or presented as a linear "top line" or "bottom line". When it is necessary to represent (or mark) the position of a certain top point and bottom point of the slope, it is often necessary to clearly specify its distance from the fixed axis O1 (that is, the radius). This embodiment of the displacement acquisition mechanism adopts a structural method in which the first hole groove 7a is matched with the push rod 8, which prompts the second constraint body 6 to produce a movement relative to the first constraint body 5, and the movement is a stretching and closing displacement movement along the direction of the motion-matching secondary fixed axis O1. The following takes the push rod 8 and the first hole groove 7a that are paired with each other as an example to describe the basic principle of the displacement acquisition mechanism: See Figures 13 to 20, and assuming that the tappet 8 is provided on the second constraint body 6 and serves as a moving part, and assuming that the first hole slot 7a is provided on the first constraint body 5 and serves as a static part, wherein Figure 20 Where: r is the equivalent radius of the first inclined surface 9a, δ is the opening amplitude of the fork handle 2a relative to its retracted state, F is the direction of the circular motion of the tappet 8 when it rotates following the second restraining body 6, β is the angle (in radians) that the chin guard 2 rotates when it flips from the full helmet structure position to the half helmet structure position, and Figure 20 The first inclined surface 9a is represented by the profile line, which is the intersection line obtained by expanding the circumference according to the equivalent radius r. The intersection line is obtained as follows: ① First, imagine a cylindrical surface coaxial with the fixed axis O1 and having a radius of the equivalent radius r. ② Then, use this imaginary cylindrical surface to intersect the first inclined surface 9a. ③ Then, expand the profile line obtained by the intersection according to the equivalent radius r to obtain Figure 20 As shown in the profile, it should be noted that: the profile can be a convex profile, a concave profile, or a straight profile according to design requirements (the situation shown in the figure is the situation where a straight line segment is used as the main body of the profile). In addition, the profile can be a single type of profile such as a single straight line, a single arc, a single parabola, a single ellipse, a single catenary, a single trigonometric function line or other function lines. Of course, the profile can also be obtained by combining or synthesizing various different function curves; Figure 20 The state shown in (a) is that the tappet 8 is in contact with the first slope 9a at the bottom of the slope and the chin guard 2 is in the full helmet structure position. At this time, the fork 2a is in the position closest to the symmetry plane P and is in a retracted state relative to the helmet shell body 1 (see Figures 1 to 6 、 Figure 23 ), when the fork handle 2a is in the retracted state, the outer surface of the fork handle 2a that is farthest from the symmetry plane P can achieve a smooth transition with the outer surface of the helmet shell body 1, and thus the helmet can obtain good aerodynamic performance; Figure 20 (b) shows the state where the tappet 8 is in the climbing stage and is in contact with the first inclined surface 9a on the slope. In response, the chin guard 2 is in the process of being opened and separated from its full helmet structure, and the fork handle 2a is gradually moving away from the symmetry plane P and is gradually opening relative to the helmet shell body 1 (as shown in FIG. Figure 18 and Figure 19 As shown), the fork handle 2a at this time shows that the opening amplitude δ is gradually increasing relative to its retracted state position (on the contrary, when the tappet 8 is on the downhill, the δ value is gradually decreasing). Figure 19 and Figure 3 Compare and Figure 23 and Figure 24By comparison, it is not difficult to find that the δ value here reflects the degree of opening of the fork handle 2a of the jaw guard 2 relative to the helmet shell body 1, which is different from Figure 3 The fork handle 2a in the retracted state is different. Figure 19 The fork handle 2a in the middle is expanded outward on one side by an amplitude δ, so that the jaw guard 2 can easily avoid the restraint of the outer surface of the helmet shell body 1 and the shield 4 when it is opened and turned over; Figure 20The state represented by (c) is that the strut 8 has climbed out of the slope of the first inclined surface 9a and has passed the top of the slope, and the fork handle 2a shows a more open posture relative to its retracted and stored state position (or the fork handle 2a is already at a position farther away from the said symmetry plane P). At this time, the opening amplitude δ of the fork handle 2a has reached the threshold value that can avoid the restraint of the helmet shell body 1 and the shield 4, thereby ensuring that the jaw guard 2 can climb over the helmet shell body 1 and the shield 4 to realize its conversion between the full helmet structure position and the half helmet structure position. It is not difficult to find that: ① When the jaw guard 2 is driven by human power or spring force to open and leave its full helmet structure position (at this time, the tappet 8 moves in the direction of F), and during this period, the tappet 8 starts to climb from the "bottom of the slope" of the first slope 9a and maintains contact with the first slope 9a, the tappet 8 as a moving part is in the "uphill" or "climbing" stage. It is noted that the first constraint body 5 is a stationary component relative to the helmet shell body 1, and the tappet 8 and the first slope 9a are in a rigid counter-action, so as the jaw guard 2 gradually leaves its full helmet structure position, the uphill behavior of the tappet 8 will be continued, and at the same time As the push rod 8 moves uphill, the second constraint body 6 will move away from the symmetry plane P (that is, the opening amplitude δ of the fork handle 2a relative to its retracted and stored state is increasing), and until the push rod 8 climbs to the top of the first slope 9a (that is, at this time the push rod 8 has completely climbed out of the first hole groove 7a). Obviously, when the push rod 8 is completely in the "top of the slope" state of the first slope 9a, the second constraint body 6 will be forced to be at a position farther away from the symmetry plane P. At this time, the fork handle 2a of the jaw guard 2 is in a more outward state relative to the helmet shell body 1. This state is conducive to the jaw guard 2 avoiding the constraints of the helmet shell body 1 and the shield 4 when rotating and being able to convert its position and posture.② When the chin guard 2 is in the stage of falling back to the full helmet structure position under human drive, spring force, gravity drive or even inertial force drive (responding to the pusher 8 moving in the opposite direction of F), if the pusher 8 comes into contact with the first inclined surface 9a at this time, then the pusher 8 as the moving part is in the "downhill" stage. Note that the first constraint body 5 is a stationary component relative to the helmet shell body 1 and the pusher 8 and the first inclined surface 9a are in rigid contact. Therefore, as the chin guard 2 gradually approaches the full helmet structure position, the downhill behavior of the pusher 8 will also continue, accompanied by As the tappet 8 descends, the second restraining body 6 approaches the plane of symmetry P until the tappet 8 fully enters the first slot 7a (i.e., the tappet 8 is completely at the "bottom" of the first slope 9a). At this point, the chin guard 2 is in a fully full-face helmet configuration. Obviously, when the tappet 8 is at the bottom, the fork 2a is closest to the plane of symmetry P and appears to be retracted relative to the helmet shell 1, thereby improving the aerodynamics of the helmet and, in turn, reducing the whistling sound and wind resistance generated by airflow during driving, while also reducing the size and weight of the helmet. Clearly, when the tappet 8 (or the first slot 7a) is in continuous contact with the main slope of the first slope 9a, it means that the tappet 8 or the first slot 7a is climbing or descending, and the fork 2a of the chin guard 2 is currently opening or closing. It is particularly important to note that the first hole groove 7a is provided on the first constraint body 5 and the tappet 8 (eg, corresponding thereto) is provided on the second constraint body 6 . Figures 13 to 17 As shown in the figure), and the first hole groove 7a is provided on the second constraint body 6 and the tappet 8 (not shown in the figure) is provided on the first constraint body 5. The slope direction of the first inclined surface 9a provided in the former is opposite to the slope direction of the first inclined surface 9a provided in the latter. However, both of them produce the same behavior of moving away from or approaching the second constraint body 6. In this embodiment of the displacement obtaining mechanism, the jaw guard 2 is opened and disengaged (see Figure 18 and Figure 19) or returns to its full-helmet structural position process, the support column 8 and the first hole groove 7a are in contact with each other at the first inclined surface 9a, and through this contact behavior, the second constraint body 6 produces a movement relative to the first constraint body 5, which is a displacement movement away from or close to the symmetry plane P of the helmet shell body 1 along the said motion matching sub-fixed axis O1, so that the fork handle 2a is driven by the second constraint body 6 and then the chin guard 2. In other words, it is finally achieved to constrain and drive the fork handle 2a of the chin guard 2 to achieve both fixed-axis rotation around the fixed axis O1 and to achieve a distance and approach relative to the symmetry plane P of the helmet shell body 1. The jaw guard 2 is in the full-helmet structural position state, and its fork handle 2a is in a retracted state relative to the helmet shell body 1, so as to facilitate the helmet to obtain a good aerodynamic shape, and when the jaw guard 2 is flipped, its fork handle 2a can be stretched out to avoid the restraint of the helmet shell body 1 without affecting the conversion of the jaw guard between the full-helmet position and the half-helmet position. It should be noted that, during the entire process of lifting the chin guard 2 and changing it from the full-helmet structure position to the half-helmet structure position, or during the entire process of retracting the chin guard 2 and returning it from the half-helmet structure position to the full-helmet structure position, the mutually echoing paired struts 8 and the first hole slots 7a are not always in overlapping or contacting positions, that is, the first hole slots 7a and the struts 8 are not in contact at the first inclined surface 9a throughout the entire process, which means that when the first hole slots 7a and the struts 8 are not in contact at the first inclined surface 9a, the fork handle 2a of the chin guard 2 can stop making the opening or closing displacement action.

[0080] b) Second embodiment of displacement acquisition mechanism

[0081] In response to the first restraint body 5 and the second restraint body 6 arranged on the same side of the helmet shell body 1, a tension column 10 is provided on the second restraint body 6 and / or the fork handle 2a, and a first limiting structure 10a is provided on the tension column 10. In addition, a second limiting structure 10b is also provided on the first restraint body 5, the base 3 or the helmet shell body 1. Figure 21 The situation shown is an example of a second limiting structure 10b being provided on the first constraint body 5; the first limiting structure 10a and / or the second limiting structure 10b include a first inclined surface 9a. Figure 21 In the illustrated case, both the first limiting structure 10a and the second limiting structure 10b are provided with a first inclined surface 9a, wherein r is the equivalent radius of the first inclined surface 9a, δ is the opening amplitude of the fork handle 2a relative to its retracted storage state, F is the direction of the circular motion of the tension column 10 when it rotates following the second constraint body 6, and β is the angle (in radians) that the jaw guard 2 rotates when it flips from the full helmet structure position to the half helmet structure position. Figure 21(a) The position of the tension column 10 shown by the solid line corresponds to the position of the chin guard 2 in the full helmet structure, while the position of the tension column 10 shown by the dotted line corresponds to the position of the chin guard 2 in the half helmet structure; Figure 21 (c) shows a cross-section in the direction of k, which is intended to further illustrate the structural details of the tension column 10, the first limiting structure 10a, and the second limiting structure 10b. Similar to the principle of the displacement acquisition mechanism in the previous embodiment a), in this embodiment: in response to the process of the chin guard 2 being opened and separated from or returned to its full-face helmet structure, the first limiting structure 10a and the second limiting structure 10b have a contact behavior at the first inclined surface 9a they contain. When this contact behavior occurs, the inclined surface 9a of the inclined structure will derive a component force to act on the tension column 10, and then the tension column 10 pulls the second constraint 6, causing the second constraint 6 to produce a corresponding displacement movement. Obviously, the contact behavior of the first limiting structure 10a and the second limiting structure 10b at the first inclined surface 9a can cause the second constraint 6 to produce a displacement movement away from or close to the symmetry plane P of the helmet shell body 1, thereby forming a displacement acquisition mechanism.

[0082] c) Displacement Acquisition Mechanism Embodiment 3

[0083] In response to the first restraining body 5 and the second restraining body 6 arranged on the same side of the helmet shell body 1, a groove-shaped track groove 11 is provided on the first restraining body 5, the base 3 or the helmet shell body 1, and a load-bearing pin 12 is provided on the second restraining body 6 and / or the fork handle 2a. In other words, the load-bearing pin 12 can be provided solely on the second restraining body 6, solely on the fork handle 2a, or simultaneously on the second restraining body 6 and the fork handle 2a. Figure 22 The example shown is that the load-bearing pin 12 is arranged on the second constraint body 6, and the track groove 11 is arranged on the first constraint body 5, and the load-bearing pin 12 is inserted into the track groove 11 and constrained by it; or, in response to the first constraint body 5 and the second constraint body 6 arranged on the same side of the helmet shell body 1, a groove-shaped track groove 11 is provided on the second constraint body 6 or / and the fork handle 2a, and at the same time, a load-bearing pin 12 is provided on the first constraint body 5, the base 3 or the helmet shell body 1, and the load-bearing pin 12 is inserted into the track groove 11 and constrained by the track groove 11 (not shown in the figure). In addition, a first inclined surface 9a is provided in the track groove 11, and the first inclined surface 9a is a curved slope-shaped structure; in Figure 22 Where r is the equivalent radius of the first inclined surface 9a, δ is the opening amplitude of the fork handle 2a relative to its retracted state, F is the direction of the circular motion of the load-bearing pin 12 when it rotates following the second constraint body 6, β is the angle (in radians) that the chin guard 2 rotates when it flips from the full helmet structure position to the half helmet structure position, where Figure 22 (a) The position of the bearing pin 12 shown by the solid line corresponds to the position of the chin guard 2 in the full helmet structure, while the position of the bearing pin 12 shown by the dotted line corresponds to the position of the chin guard 2 in the half helmet structure; Figure 22 A t-direction cross-section, an m-direction cross-section, and an n-direction cross-section are used to further illustrate the structural details of the load-bearing pin 12 and the track groove 11. Similar to the principle of the displacement acquisition mechanism in the previous embodiment a), in this embodiment, in response to the chin guard 2 being opened and disengaged from, or returning to, the full-face helmet structure, the load-bearing pin 12 and the track groove 11 engage in contact at the first inclined surface 9a. This contact enables the second constraint body 6 to generate a displacement movement away from or toward the symmetry plane P of the helmet shell body 1, thereby forming a displacement acquisition mechanism.

[0084] It should be pointed out in particular that the three displacement obtaining mechanisms a), b), and c) listed above are merely three preferred solutions for achieving the displacement action of the second constraint body 6 away from or close to the symmetry plane P of the helmet shell body 1. They cannot limit the present invention to adopt only these solutions and not other technical solutions. Instead, it means that "the displacement obtaining mechanism adopts or includes at least one of the following a), b), and c) displacement obtaining mechanisms". This sentence has two meanings: one meaning is that the displacement obtaining mechanism in the present invention adopts and only adopts at least one of the three displacement obtaining mechanisms a), b), and c); the other meaning is that the displacement obtaining mechanism in the present invention can adopt other types of displacement obtaining mechanisms but also It includes at least one of the three displacement obtaining mechanisms a), b), and c); specifically, the three displacement obtaining mechanisms a), b), and c) can be used individually, for example, the a) displacement obtaining mechanism is used on both sides of the helmet shell body 1, or they can be used in combination, for example, the a) displacement obtaining mechanism is used on one side of the helmet shell body 1 and the b) displacement obtaining mechanism is used on the other side of the helmet shell body 1. It is even possible to use two or more displacement obtaining mechanisms on the same side of the helmet shell body 1 to jointly prompt the second constraint body 6 to perform the same displacement behavior, for example, using a) and c) together to generate an opening displacement action of the second constraint body 6 away from the symmetry plane P or to generate a closing displacement action of the second constraint body 6 close to the symmetry plane P. In addition to the three preferred displacement obtaining mechanisms a), b), and c) mentioned above, the displacement obtaining mechanism that participates in causing the second constraint body 6 to perform the opening and closing displacement action may also include various displacement obtaining mechanisms designed and manufactured based on the principles of mechanism pushing and pressing, spring support and contraction, magnetic attraction and repulsion, etc. For example, a) displacement obtaining mechanism is used on one side of the helmet shell body 1 and a displacement obtaining mechanism composed of a spring body or / magnetic body is used on the other side of the helmet shell body 1. For example, a) displacement obtaining mechanism and a spring-type displacement obtaining mechanism are used on the same side of the helmet shell body 1 to jointly cause the second constraint body 6 to perform the same displacement behavior. They are not listed one by one here.

[0085] Furthermore, in order to ensure that the jaw guard 2 has better stability when converting its position and posture between the full helmet structure position and the half helmet structure position, the present invention can configure a load-bearing member 13 on the second constraint body 6 and / or the fork handle 2a (that is, there are three situations, namely, the load-bearing member 13 is configured on the second constraint body 6 alone, or the load-bearing member 13 is configured on the fork handle 2a alone, or the load-bearing member 13 is configured on both the fork handle 2a and the fork handle 2a at the same time), and this load-bearing member 13 is fastened to or integrally manufactured on the second constraint body 6 and / or the fork handle 2a (that is, the load-bearing member 13 is fastened to or integrally manufactured on the second constraint body 6, or the load-bearing member 13 is fastened to or integrally manufactured on the fork handle 2a, or the load-bearing member 13 is fastened to or integrally manufactured on both the second constraint body 6 and the fork handle 2a), wherein Figure 13 、 Figure 23 and Figure 24 The illustrated embodiment shows the load-bearing member 13 being fastened to the fork handle 2a with screws. At least one energy storage spring 14 is disposed between the load-bearing member 13 and the first restraining body 5, or between the load-bearing member 13 and the base 3, or between the load-bearing member 13 and the helmet shell body 1. One end of the energy storage spring 14 abuts against the load-bearing member 13, while the other end abuts against the first restraining body 5, the base 3, or the helmet shell body 1. In other words, the energy storage spring 14 is disposed between the load-bearing member 13 and at least one of the first restraining body 5, the base 3, and the helmet shell body 1, and one end of the energy storage spring 14 abuts against at least one of the first restraining body 5, the base 3, and the helmet shell body 1. Figure 23 and Figure 24The illustrated situation is an example in which an energy storage spring 14 is provided between the load-bearing member 13 and the first constraint body 5, with one end of the energy storage spring 14 resting on the load-bearing member 13 and the other end resting on the first constraint body 5. It should be noted that the "resting" mentioned here includes various situations such as the energy storage spring 14 directly resting on the load-bearing member 13, or the energy storage spring 14 directly resting on the first constraint body 5, or the energy storage spring 14 directly resting on the base 3, or the energy storage spring 14 directly resting on the helmet shell body 1. Of course, it also includes situations in which the energy storage spring 14 indirectly rests on the load-bearing member 13, the first constraint body 5, the base 3, or the helmet shell body 1 through an intermediate member. It should also be noted that the first constraint body 5, the second constraint body 6, and the base 3 involved in this case, which are functionally interconnected, are all distributed on the same side of the helmet shell body 1. The advantage of setting the load-bearing member 13 and the energy storage spring 14 in the present invention is that the elastic force of the energy storage spring 14 can be used to effectively eliminate the matching gap between the various components, which is beneficial to improving the stability, reliability and safety of the helmet. In particular, the energy storage spring 14 can also be used to prompt the second constraint body 6 to move away from or towards the symmetry plane P of the helmet shell body 1 during the process of the jaw guard 2 being opened and separated or returning to the full helmet structure position. This task can be undertaken by the energy storage spring 14 alone, or the energy storage spring 14 can be used to assist other constraints to jointly undertake it. It can be seen that the energy storage spring 14 here actually becomes one of the important components of the displacement obtaining mechanism, or the energy storage spring 14 can simply be used as a displacement obtaining mechanism alone. During the process stage of the chin guard 2 being opened and separated from or returning to the full-face helmet structure position, the energy storage spring 14 dominates or participates in causing the fork handle 2a to generate a displacement action away from or close to the symmetry plane P of the helmet shell body 1; in particular, the present invention can adopt such an action to obtain a combination to achieve the displacement away from and towards the symmetry plane P of the chin guard 2 relative to the helmet shell body 1: during the process stage of the chin guard 2 being opened and separated from its full-face helmet structure position, the contact behavior between the push column 8 and the first hole groove 7a at the first inclined surface 9a is simply utilized to generate the displacement of the fork handle 2a away from the symmetry plane P of the helmet shell body 1; at the same time, during the process stage of the chin guard 2 returning to its full-face helmet structure position, the elastic force of the energy storage spring 14 is simply utilized to generate the displacement of the fork handle 2a towards the symmetry plane P of the helmet shell body 1. Figure 6 、 Figure 23 and Figure 24 The situation shown is an example of this combination mode. Here, the energy storage spring 14 of the present invention can be either a pressure-type or a tension-type elastic force, with the pressure-type being the best form; in addition, the number of energy storage springs 14 can be one or more; Figure 23 and Figure 24In the embodiment shown, the energy storage spring 14 is of a pressure-acting type and only one spring is used. Figure 23 The situation shown is that the fork handle 2a of the chin guard 2 is in a retracted state (corresponding to the chin guard 2 being in the full helmet structure position). Figure 24 The situation shown is that the fork handle 2a of the jaw guard 2 is in a fully opened state (corresponding to the jaw guard 2 being in the stage of rotating over the obstacle), and the energy storage spring 14 in both situations is in a compressed state, wherein the energy storage spring 14 is in a Figure 24 State than in Figure 23 In the state, it is compressed to a greater extent. Figure 24 and Figure 23 It is not difficult to find that the jaw guard 2 in the rotation obstacle crossing stage has a unilateral outward opening of the fork handle 2a of the jaw guard 2 relative to the jaw guard 2 in the full helmet structure position. It is this amplitude δ that enables the fork handle 2a of the jaw guard 2 to avoid the fetters of the helmet shell body 1 and successfully complete the transformation of its posture. In addition, the load-bearing member 13 in this case can be a disc-shaped structure (such as Figure 6 、 Figure 23 and Figure 24 As shown), it can also be a ring groove structure, or even a slatted structure or a flanged structure, and of course it can also be other structural forms.

[0086] In order to make the jaw guard 2 obtain better motion stability during the process of changing its position and posture, and to effectively reduce the complexity of the operation constraint mechanism of the jaw guard 2, the present invention is particularly provided with a first hole groove 7a on the first constraint body 5 and only on the first constraint body 5, and a tappet 8 corresponding to the first hole groove 7a is provided on the second constraint body 6 and only on the second constraint body 6. Figures 13 to 17 The case shown belongs to this situation), or the first hole groove 7a is provided on the second constraint body 6 and is only provided on the second constraint body 6, and the first hole groove 7a is provided on the first constraint body 5 and is only provided on the first constraint body 5. The first hole groove 7a and the tappet 8 corresponding to the first hole groove 7a are arranged on the same side of the helmet shell body 1, and their number is greater than or equal to three, and the first hole grooves 7a and the tappet 8 are matched in pairs one by one ( Figures 13 to 17Shown are the first hole slots 7a and the push rods 8, both of which are three in number. The first inclined surface 9a of each pair of first hole slots 7a and push rods 8 includes an equivalent radius with the fixed axis O1 of the motion matching pair as the measurement starting point, and the larger the equivalent radius of the first inclined surface 9a, the smaller the value of the equivalent slope it has, that is, the gentler its slope. It is particularly important to point out that, when the first hole slot 7a and the push rod 8 that are paired with each other are both provided with the first inclined surface 9a (that is, both the first hole slot 7a and the push rod 8 of the same paired pair are simultaneously provided with the first inclined surface 9a), for the sake of simplicity, the present invention can take only one of the first inclined surfaces 9a as the measurement object of the equivalent radius of the paired pair. For example, only the first inclined surface 9a on the first hole slot 7a can be used to define and calculate the equivalent radius of the paired pair, or only the first inclined surface 9a on the push rod 8 can be used to define and calculate the equivalent radius of the paired pair. In this way, in the present invention, for each pair of the first hole slot 7a and the push rod 8, there is one and only one equivalent radius, which can simplify the subsequent description. Obviously, using a larger number of tappets 8 and first slots 7a for pairing will undoubtedly help improve the stability of the opening and closing displacement movement of the jaw guard 2 fork 2a. The larger the equivalent radius of the first inclined surface 9a, the smaller the equivalent slope value it has. The purpose is to ensure that the paired tappets 8 and first slots 7a can maintain synchronization when they come into contact with their first inclined surfaces 9a. It should be pointed out that the "equivalent radius" mentioned in the present invention refers to the average radius of the set of geometric elements that constitute the first inclined surface 9a (that is, the slope formed by them), that is, the average value of the distance between each point on the slope and the fixed axis O1 of the kinematic matching pair; the so-called "equivalent slope" refers to the slope of the first inclined surface 9a at its equivalent radius, that is, the ratio of the difference in distance between the top and bottom of the slope relative to the symmetry plane P at the equivalent radius to the length of the bottom of the slope corresponding to the slope. The "equivalent slope" here can be obtained as follows: using a fixed axis O A coaxially arranged imaginary cylindrical surface with an equivalent radius is used to intersect the first inclined surface 9a. The intersection profile obtained by the intersection is then unfolded along the imaginary cylindrical surface (i.e., the imaginary cylindrical surface is cut along a generatrix thereof and flattened into a plane). Finally, the value of the "equivalent slope" is calculated on the unfolded plane according to the definition of slope. Obviously, this "equivalent slope" can reflect the inclination value of the slope surface relative to the symmetry plane P, wherein the slope surface refers to the display of the first inclined surface 9a obtained when the circumference is unfolded according to the equivalent radius.

[0087] Furthermore, the equivalent radius values of the first inclined surfaces 9a of all the paired first slots 7a and push rods 8 are not equal to each other, that is, the radius length values of the equivalent radius of each paired first slots 7a and push rods 8 in this case are all different, and when the second constraint body 6 rotates around the fixed axis O1 of its motion matching pair, the contact behavior of each paired push rod 8 and first slot 7a at the equivalent radius of their respective first inclined surfaces 9a all present a timing pattern of synchronous contact and synchronous separation. It should be noted that the equivalent radius of the first inclined surface 9a of each pair of first hole slots 7a and tappet 8 is involved here. As mentioned above, for the sake of simplicity, in the present invention: when one and only one of the paired first hole slots 7a and tappet 8 is provided with the first inclined surface 9a, there is no doubt that the paired pair has one and only one equivalent radius; when the paired first hole slots 7a and tappet 8 are both provided with the first inclined surface 9a at the same time, the present invention takes and only takes one of the first inclined surfaces 9a as the object for calculating the equivalent radius, that is, in this case, each pair of first hole slots 7a and tappet 8 still has and only has one equivalent radius. Regarding the contact behavior of each paired tappet 8 and first slot 7a at the equivalent radius of its first inclined surface 9a, the following example can be used to describe it: assuming that there are three pairs of tappets 8 and first slots 7a, the contact behavior of these three tappets 8 and first slots 7a at their respective first inclined surfaces 9a is not only synchronized when in contact, but also synchronized when separated. That is to say, the contact behavior and separation behavior that occur in these three different pairs, although they occur in different places, are consistent in time and order. Or, to be more specific, as long as one of the three tappets 8 and first slots 7a contacts at its first inclined surface 9a, the other two tappets 8 and first slots 7a must also contact at their respective first inclined surfaces 9a; conversely, the separation behavior of each pair of tappets 8 and first slots 7a at their respective first inclined surfaces 9a will also be consistent and synchronized. It is particularly important to note here that the "synchronous contact" and "synchronous separation" described in the present invention allow for asynchronous errors within the engineering allowable range caused by various reasons such as manufacturing errors, assembly errors, and stress deformation. In other words, those asynchronous errors and inconsistent errors that do not affect the normal use of the helmet can be ignored. Or, more specifically, although there are some minor asynchronous phenomena that do not affect the normal use of the helmet (that is, these asynchronous phenomena do not hinder the normal posture conversion of the jaw guard 2), the present invention uniformly regards the contact and separation of each paired strut 8 and the first hole groove 7a at the first inclined surface 9a as synchronous and consistent.The present invention arranges the equivalent radius of the first inclined surface 9a of each pair of the first hole groove 7a and the tappet 8 to be unequal in value (in short, there are as many equivalent radii of different values as there are pairs of the first hole groove 7a and the tappet 8. For example, there are three pairs of the first hole groove 7a and the tappet 8, which correspond to three equivalent radii of different values). The purpose and advantage of this is to optimize the layout of each pair of the first hole groove 7a and the tappet 8. In this way, each pair (or each pair) of the first hole groove 7a can be arranged to have a different equivalent radius. The slot 7a and the tappet 8 are at different distances from the fixed axis O1, so they can effectively avoid interference in space; in addition, the contact behavior of each paired tappet 8 and the first slot 7a at the equivalent radius of their respective first inclined surfaces 9a is arranged to be in a timing pattern of synchronous contact and synchronous separation. The purpose and advantage of this is mainly to optimize and improve the movement stability, firmness and reliability of the jaw guard 2, because in this way, each contact pair can achieve synchronous contact at different support points, which means that they achieve synchronous force.

[0088] In order to allow the helmet to achieve the sinking effect in the half-helmet state, the present invention can open the second hole groove 7b on the first constraint body 5 and the number of the second hole groove 7b is consistent with the number of the tappet 8 provided only on the second constraint body 6 (such as Figures 13 to 17 Shown and see Figures 27 to 35 ), or the second constraint body 6 is provided with a second hole slot 7b and the number of the second hole slot 7b is consistent with the number of the tappets 8 provided only on the first constraint body 5 (not shown in the figure), that is, the tappets 8 in this case are either provided only on the first constraint body 5 (not shown in the figure) or provided only on the second constraint body 6 (as shown in 13). When the tappets 8 are provided only on the second constraint body 6 (see FIG. Figure 13 、 Figure 16 、 Figure 17 、 Figure 29 、 Figure 32 、 Figure 35 and Figure 37 ), the second hole 7b is opened on the first constraint body 5 (see Figure 13 and Figure 14 、 Figure 15 、 Figure 27 and Figure 28 、 Figure 30 and Figure 31 、 Figure 33 and Figure 34), when the support column 8 is only provided on the first constraint body 5, the second hole groove 7b is provided on the second constraint body 6 (not shown in the figure). Regardless of the above situation, the second hole groove 7b and the support column 8 described in this case are paired in a one-to-one manner, and the paired second hole groove 7b and the support column 8 include a second inclined surface 9b with a slope shape relative to the symmetry plane P of the helmet shell body 1; here, the second hole groove 7b and the support column 8 that are paired with each other can be provided on the second hole groove 7b alone, can be provided on the support column 8 alone, or can be provided on the second hole groove 7b and the support column 8 at the same time; the present invention responds to the process stage of the jaw guard 2 flipping out of or approaching to sit in its half-helmet structure position, and the paired support column 8 and the second hole groove 7b are on their second inclined surface 9b There is a mutual contact behavior at each part, and these contact behaviors can cause the second constraint body 6 to produce a displacement action close to or away from the symmetry plane P of the helmet shell body 1. It can be seen that the above-mentioned first constraint body 5 (including the second hole groove 7b opened thereon), the second constraint body 6 (including the second hole groove 7b opened thereon), the support column 8 and the second inclined surface 9b opened on these components actually constitute a displacement obtaining mechanism. Therefore, especially under the constraint of this displacement obtaining mechanism, when the chin guard 2 is in the half-helmet state, its fork handle 2a can be expressed in a retracted and stored posture, which is beneficial to the helmet to obtain a good aerodynamic shape by participating in the appearance expression of the helmet (see Figures 7 to 12), on the other hand, the storage structure can also increase the degree to which the jaw guard 2 sticks to the helmet shell body 1, thereby helping to improve the reliability and safety of the helmet. It should be pointed out that the first constraint body 5, the second constraint body 6, the first hole slot 7a, the push rod 8, and the second hole slot 7b on the same side of the symmetry plane P, if the first hole slot 7a and the second hole slot 7b are only provided on the first constraint body 5, and at the same time, the push rod 8 that corresponds to these hole slots is only provided on the second constraint body 6 (including the push rod 8 being provided on the fork handle 2a), then their first inclined surface 9a and the second inclined surface 9b are inclined in opposite directions with respect to the symmetry plane P; similarly, if the first hole slot 7a and the second hole slot 7b are only provided on the second constraint body 5, and at the same time, the push rod 8 that corresponds to these hole slots is only provided on the first constraint body 6, then they The first bevel 9a and the second bevel 9b are also arranged in opposite directions with respect to the symmetry plane P; by extension, as long as the first bevel 9a and the second bevel 9b are on the same component, the inclination directions of the two are opposite; in other words, if the inclination direction of the first bevel 9a on a certain component is right-handed, then the second bevel 9b on the component must be left-handed (and vice versa), especially including the case where the first bevel 9a and the second bevel 9b are simultaneously provided on the tappet 8, then if one of the first bevel 9a and the second bevel 9b included in the tappet 8 is "left-handed" inclined, then the other is "right-handed" inclined (such as Figure 13 、 Figure 16 、 Figure 17 、 Figure 20 、 Figure 29 、 Figure 32 and Figure 35 As shown). It is not difficult to infer from this that, in response to the process stage of the jaw guard 2 flipping out of or moving closer to its half-helmet structural position, the support column 8 and the second hole slot 7b are in contact with each other at the second inclined surface 9b, and the contact behavior can be used to drive the second constraint body 6 to move, so that the second constraint body 6 produces a displacement action relative to the symmetry plane P of the helmet shell body 1 along the direction of the motion matching sub-fixed axis O1. At this time, the second hole slot 7b and the second inclined surface 9b also participate in the formation of a displacement acquisition mechanism that can cause the fork handle 2a of the jaw guard 2 to produce an opening and closing displacement action away from or close to the symmetry plane P of the helmet shell body 1. In order to more clearly illustrate the difference in their behavioral performance caused by the difference in their structural layout in the present invention, we use a better embodiment description of the sequential planning of their behaviors to show the process of the jaw guard 2 participating in constraining the opening and closing displacement action of the second constraint body 6 when it switches between the full helmet structural position and the half helmet structural position (see Figure 20 ):

[0089] 1) When the jaw guard 2 is flipped from the full helmet structure position to the half helmet structure position and its position and posture are changed (such as Figure 25 As shown in the figure): ① The jaw guard 2 starts to flip from the full helmet structure position and moves towards the half helmet structure position → ② until the paired tappets 8 and the first hole groove 7a come into contact with each other at the first inclined surface 9a contained therein (the tappets 8 start to climb the slope) → ③ Then the second constraint body 6 rotates around the fixed axis O1 and at the same time, the second constraint body 6 also makes an opening displacement action away from the symmetry plane P under the action of the displacement obtaining mechanism (at this time, the fork handle 2a of the jaw guard 2 shows an opening degree of amplitude δ relative to its original sunken position) → ④ until the tappets 8 climb out of the top of the first inclined surface 9a and complete the full opening of the fork handle 2a of the jaw guard 2 (at this time, the amplitude δ becomes larger) →⑤ The jaw guard 2 continues to flip over and climb over the outer surface of the helmet shell and the shield 4 (at this time, the tappet 8 does not contact the first inclined surface 9a and the second inclined surface 9b) →⑥ until the paired tappet 8 and the second hole groove 7b contact each other at the second inclined surface 9b contained therein (the tappet 8 starts to go downhill) →⑦ Then the second constraint body 6 rotates around the fixed axis O1 and the second constraint body 6 also performs a closing displacement action close to the symmetry plane P under the action of the displacement obtaining mechanism →⑧ until the tappet 8 climbs to the bottom of the second inclined surface 9b and completes the complete closing of the jaw guard 2 fork 2a →⑨ Finally, the jaw guard 2 is placed in the half helmet structure. Echoing the above process: Figure 25 (a) The chin guard 2 is in the full-face helmet configuration, with the fork handle 2a retracted and stored. Figure 25 (b) The chin guard 2 is in the process of being opened and separated from the full helmet structure. At this time, the tappet 8 comes into contact with the first inclined surface 9a and the fork handle 2a is gradually opened accordingly; Figure 25 (c) The jaw guard 2 is in the stage of preparing to climb over the fully opened guard 4. At this time, the tappet 8 is out of contact with the first inclined surface 9a and the fork handle 2a is in the fully opened state. Figure 25 (d) is the stage where the jaw guard 2 is in the process of climbing over the guard 4 in the fully opened state, at which time the tappet 8 is not in contact with the first inclined surface 9a and the second inclined surface 9b and the fork handle 2a is kept in the fully opened state; Figure 25 (e) The jaw guard 2 has climbed over the fully opened shield 4 and is climbing over the dome of the helmet shell body 1. At this time, the tappet 8 is not in contact with the first inclined surface 9a and the second inclined surface 9b, and the fork handle 2a is kept in a fully opened state. Figure 25 (f) The chin guard 2 is completely positioned in the half-helmet structure. At this time, the tappet 8 has entered the bottom of the second inclined surface 9b, and the fork handle 2a is correspondingly retracted and stored again.

[0090] 2) When the jaw guard 2 is flipped from the half helmet structure position to the full helmet structure position and its position and posture are changed (such as Figure 26 As shown in the figure): ① The jaw guard 2 starts to flip from the half-helmet structure position and returns to the full-helmet structure position → ② until the paired tappets 8 and the second hole slots 7b come into contact with each other at the second inclined surface 9b contained therein (the tappets 8 start to climb) → ③ Then the second constraint body 6 rotates around the fixed axis O1 while the second constraint body 6 also makes an opening displacement action away from the symmetry plane P under the action of the displacement obtaining mechanism → ④ until the tappets 8 climb out of the top of the second inclined surface 9b and complete the full opening of the jaw guard 2 fork 2a → ⑤ The jaw guard 2 continues to flip over and climb over the outer surface of the helmet shell body and The shield 4 moves (at this time, the tappet 8 does not contact the second inclined surface 9b and the first inclined surface 9a) → ⑥ until the paired tappet 8 and the first hole 7a contact each other at the first inclined surface 9a contained therein (the tappet 8 starts to go downhill) → ⑦ Then the second constraint body 6 rotates around the fixed axis O1 and at the same time, the second constraint body 6 also makes a closing displacement action close to the symmetry plane P under the action of the displacement obtaining mechanism → ⑧ until the tappet 8 climbs to the bottom of the first inclined surface 9a and completes the complete closing of the chin guard 2 fork 2a → ⑨ Finally, the chin guard 2 is placed in the full helmet structure. Echoing the above process: Figure 26 (a) shows the chin guard 2 in the half-helmet configuration, with the fork handle 2a retracted and stored. Figure 26 (b) The chin guard 2 is on its way back to the full helmet structure and is climbing over the dome of the helmet shell body 1. At this time, the tappet 8 is not in contact with the first inclined surface 9a and the second inclined surface 9b, and the fork handle 2a is in a fully opened state. Figure 26 (c) The jaw guard 2 is in the stage of climbing over the fully opened guard 4. At this time, the tappet 8 is still not in contact with the first inclined surface 9a and the second inclined surface 9b, and the fork handle 2a is still in the fully opened state. Figure 26 (d) The jaw guard 2 has already climbed over the guard cover 4 in the fully opened state, and the fork handle 2a remains in the fully opened state; Figure 26 (e) is the stage where the chin guard 2 enters the seated position of the full helmet structure, at which time the tappet 8 comes into contact with the first inclined surface 9a and the fork handle 2a is gradually retracted accordingly; Figure 26 (f) shows the chin guard is completely in place in the full helmet structure, and the fork handle 2a is now in a completely retracted state.

[0091] In order to improve the reliability of the helmet, in particular to ensure that the jaw guard 2 can be reliably pressed against the helmet shell body 1 when in the full helmet structure position and the half helmet structure position, a buckle 15a can be provided on the first restraining body 5, the base 3 or the helmet shell body 1, and a tongue 15b corresponding to the buckle 15a can be provided on the load-bearing member 13. Figure 13 As shown, Figure 29 、 Figure 32 、 Figure 35 and Figure 37 The case shown also belongs to the case where the tongue 15b is provided on the load-bearing member 13. As the jaw guard 2 rotates, the fork handle 2a and the second restraining body 6 also rotate accordingly, and the load-bearing member 13 will also rotate around the fixed axis O1, so the relative position relationship between the tongue 15b and the buckle 15a is constantly changing. However, in this case, when the jaw guard 2 is in the full helmet structure position or / and the half helmet structure position and is observed along the direction of the motion matching secondary fixed axis O1 toward the symmetry plane P of the helmet shell body 1: the buckle 15a is at a distance from the helmet shell body 1 from the tongue 15b. When the position is farther away from the symmetry plane P, and at this time, the projection of at least one buckle 15a intersects with the projection of the tongue 15b, the displacement of the load-bearing member 13 away from the symmetry plane P along the fixed axis O1 will be restricted. Note that the load-bearing member 13 and the fork handle 2a of the jaw guard 2 are fastened together, so the restriction of the buckle 15a on the tongue 15b can be used to prevent the fork handle 2a of the jaw guard 2 from abnormally dislodging and displacement due to vibration, collision and human error.

[0092] Furthermore, in the present invention, there are three first slots 7a arranged on the same side of the helmet shell body, and the three first slots 7a all include a first inclined surface 9a (such as Figure 14 and Figure 15 As shown), starting from the slope vertices corresponding to the equivalent radius of each first inclined surface 9a, perpendicular lines are drawn to the motion-matching secondary fixed axis O1, and these perpendicular lines are projected onto the symmetry plane P of the helmet shell body 1. The minimum angles formed between the projection lines of the three perpendicular lines obtained on the symmetry plane P are all no less than 90°, and the sum of the three minimum angles formed between the projection lines of the three perpendicular lines obtained is always maintained to be 360°. One of the preferred embodiments is that the minimum angles formed between the projection lines of the three perpendicular lines are all equal to 120°. The purpose of such an arrangement is to enable the jaw guard 2 to obtain better motion stability and reliability, because the first hole slot 7a of the above-mentioned herringbone layout obviously also corresponds to the provision of the support column 8 which is also in the herringbone layout (see the previous agreement and discussion), and it is a well-known fact that the structure of the herringbone layout has good stability and force-bearing characteristics.

[0093] Furthermore, the energy storage spring 14 is a conical spring, and the conical energy storage spring 14 and the fixed axis O1 of the kinematic matching pair are coaxially arranged (e.g. Figure 13 、 Figure 23 and Figure 24The advantages of using a conical spring are: 1) first, it can greatly reduce the space occupied by the energy storage spring 14 when compressed, thereby helping to reduce the volume of the helmet, which is beneficial for lightweighting, storage and transportation; 2) at the same time, the conical spring also has the characteristic of automatic return (also called automatic return to the center), thereby helping to improve the movement stability of the jaw guard 2; 3) furthermore, the conical spring is a variable stiffness spring, and thus has better anti-fatigue properties, thereby helping to improve the reliability of the helmet. In addition, the energy storage spring 14 and the fixed axis O1 of the kinematic matching pair are arranged in a coaxial layout, so that both the force condition and the layout design can be better handled: on the one hand, the force-bearing part of the energy storage spring 14 that applies the force to the second constraint body 6 is mainly distributed in the central area around the fixed axis O1 of the kinematic matching pair, which is beneficial to the operational stability of the jaw guard 2; on the other hand, the energy storage spring 14 being in the central area is also beneficial to the layout design of the second constraint body 6 and the first constraint body 5, and further, it can be beneficial to the structure and layout design of the fork handle 2a of the jaw guard 2; in addition, the typical layout of the conical energy storage spring 14 is also the preferred layout: its large end is against the first constraint body 5, and its small end is against the load-bearing member 13 (see Figure 23 and Figure 24 ), or conversely, the small end of the conical energy storage spring 14 is pressed against the first constraint body 5, and the large end is pressed against the load-bearing member 13. The advantages and effects of these two spring layouts are basically the same.

[0094] Furthermore, the load-bearing member 13 and / or its connecting accessories are made of a magnetically attractive material or are simply magnets, and magnets or magnetically attractive components (not shown) are provided on the helmet shell body 1, the base 3, or the first restraining body 5 to correspond therewith and together form a magnetic pair. The connecting accessories of the load-bearing member 13 include various parts connected to the load-bearing member 13, as well as fasteners such as screws and washers that connect the load-bearing member 13 to the second restraining body 6 or to the fork handle 2a. The advantage of setting up magnets and using magnetically attractive materials is that the driving force of the energy storage spring 14 can be compensated, because the characteristic of the magnetic attraction force is that the closer the two acting magnets are to each other, the stronger the magnetic force generated is, and the action characteristic of the spring is that the smaller the spring body deviates from its free state (also called free length), the weaker the force it generates, and vice versa. Therefore, as long as the mechanical properties of the two are fully utilized to arrange them to generate the opening and closing displacement action that drives the second constraint body 6, for example, a magnetic acting body dominated by the attraction force is arranged at the end of the extension of the spring dominated by the compression force, the gradually increasing magnetic attraction force can be used to compensate for the gradually weakening spring force, which can greatly help to improve the stability and reliability of the jaw guard 2.

[0095] The shield 4 of the present invention comprises two supporting side edges 4a, which are separated by a symmetry plane P and are located on both sides of the helmet shell body 1, that is, they are separated by the symmetry plane P (such as Figure 13 As shown); wherein at least one base 3 includes an outer cover 3a and a bottom cover 3b, and a driving gear 16 that can rotate on a fixed axis, a rack 17 that meshes with the driving gear 16, and a power spring 18 that can drive the driving gear 16 to rotate (as shown in FIG. Figure 13 As shown), the rack 17 is interconnected with the supporting side 4a of the shield 4, and an arc-shaped outer guide groove 19a is provided on the outer cover 3a and / or the helmet shell body 1, and an arc-shaped inner guide groove 19b is provided on the bottom cover 3b and / or the helmet shell body 1. The outer guide groove 19a and the inner guide groove 19b together constitute a pair of constraint guide rails and use the constraint guide rails to constrain the position and posture of the rack 17, so as to achieve the purpose of controlling the position and posture of the shield 4 through the rack 17; it should be pointed out that the outer guide groove 19a and the inner guide groove 19b can be either a flange-shaped track constraint structure or a through-groove-shaped track constraint structure, or a hybrid constraint structure that includes a partial through-groove-shaped structure combined with other non-through-groove-shaped structures. Figure 13 The example in which an outer guide groove 19a is formed on the outer cover 3a, and at least a portion of the main structure of the outer guide groove 19a is in the shape of a through groove, and an inner guide groove 19b is formed on the bottom cover 3b, and at least a portion of the main structure of the inner guide groove 19b is in the shape of a through groove is shown; Figure 33 and Figure 34 The example is shown in which an outer guide groove 19a is provided on the outer cover 3a, and a part of the main structure of the outer guide groove 19a is in the shape of a through groove. In particular, the present invention also includes a situation in which the inner guide groove 19b and the outer guide groove 19a and the constraint guide rail formed by them are all in the form of arc-shaped structural constraints. In other words, due to their constraints, the movement of opening or closing the shield 4 will be in the form of fixed-axis rotation or fixed-axis swing. Moreover, compared with the traditional rocker arm constraint form, the constraint structure of the shield 4 in the present invention abandons the rocker arm, so it occupies less space, thereby providing more flexible conditions for the layout design of the shield 4. Here, a point of force of the power spring 18 acts on the drive gear 16 (such as Figure 29 、 Figure 32 and Figure 35As shown in the figure), another point of force of the power spring 18 can fall on the base 3 or on the helmet shell body 1 (not shown in the figure), wherein the influence of the force exerted by the power spring 18 always forces the shield 4 to be opened. Of course, this posture is achieved by transmitting the power spring 18 through the engagement of the drive gear 16 with the rack 17. It should be noted that the power spring 18 in the present invention can be in the form of either a tension-action type or a pressure-action type, and in particular, a torsion-action type, wherein the torsion-action type is the preferred form because it can effectively utilize the body space of the drive gear 16 for reasonable layout (such as Figure 13 、 Figure 29 、 Figure 32 、 Figure 35 and Figure 37 As shown). It is particularly important to point out that the shield 4 of the present invention can adopt such an optimal design layout strategy: when the jaw guard 2 is in the position state of the full helmet structure, the lower edge 4b of the shield 4 can be buckled on the jaw guard 2, and the upper edge 4c of the shield 4 can be buckled on the helmet shell body 1 (as shown). Figures 1 to 3 、 Figure 27 and Figure 28 and when the shield 4 is in the fully opened position, the jaw guard 2 can make a crossing action over the shield 4 in this state and can complete the state conversion between the full helmet structure position and the half helmet structure position.

[0096] Furthermore, in order to ensure that the shield 4 can be securely maintained in the buckled position when it is in the buckled state, that is, when the shield 4 is located in front of the helmet and is in a position to block wind, sand and rain from blowing directly into the wearer's eyes and nose (see Figures 1 to 3 ), the present invention can be provided with a locking tooth mechanism on the base 3 and / or the helmet shell body 1, the locking tooth mechanism comprising an external locking tooth 17a provided on the rack 17, an internal locking tooth 17b fitted on the base 3 or the helmet shell body 1 and a locking tooth spring 17c (see Figure 13 、 Figures 27 to 37 ), the body of the inner tooth 17b is constrained by the base 3 and / or the helmet shell body 1, and under such constraints, the movement of the inner tooth 17b is in the form of linear displacement, or in the form of swinging displacement, or in the form of a composite displacement including linear displacement and swinging displacement; wherein the elastic force of the locking tooth spring 17c always forces the inner tooth 17b to abut against the outer tooth 17a. Figures 27 to 29 In the illustrated situation, the guard 4 is locked in the fully buckled position by the locking gear mechanism, that is, the lower edge 4b of the guard 4 is in contact with the guard jaw 2 (the inner locking teeth 17b and the outer locking teeth 17a are in meshing state); Figures 30 to 32In the illustrated situation, the shield 4 is locked in a slightly open position by the locking mechanism, that is, the lower edge 4b of the shield 4 is separated from the jaw 2 (the inner teeth 17b and the outer teeth 17a are also in meshing state); Figures 33 to 35 In the illustrated embodiment, the guard 4 has been unlocked and has been lifted to the fully opened position by the power spring 18 (at this point, the inner latching teeth 17b and the outer latching teeth 17a are completely disengaged). The locking spring 17c can be a tension-type, a pressure-type, or a torsion-type, with the pressure-type being preferred (see FIG. Figure 29 、 Figure 32 and Figure 35 In the present invention, when the inner teeth 17b are locked by the outer teeth 17a, the shield 4 will be kept at a certain current position, such as Figure 29 and Figure 32 As shown, when the inner latching teeth 17b are disengaged from the outer latching teeth 17a and unlocked, the shield 4 can be driven by the power spring 18 to be opened, as shown in FIG. Figure 35 shown.

[0097] In order to prevent the jaw guard 2 from accidentally falling out of the full-face helmet structure or the half-helmet structure under the action of inertia or impact, the second restraining body 6 is provided with a first slot 6a corresponding to the jaw guard 2 in the full-face helmet structure, and a second slot 6b corresponding to the jaw guard 2 in the half-helmet structure (see FIG. Figure 16 、 Figure 17 、 Figure 29 、 Figure 32 and Figure 35 ), and also equipped with a card 20 including an inclined thrust structure 20a on the bottom bracket 3 and / or the helmet shell body 1 (see Figure 27 and Figure 36 ), the card 20 abuts against the second constraint body 6, wherein the thrust structure 20a can be a flat inclined surface structure or a curved inclined surface structure or a combination of various other curved surfaces, and the abutting contact includes both direct abutting contact and indirect abutting contact through an intermediate member; Figure 29 and Figure 32 The situation shown is that the card 20 is in contact with the first card slot 6a of the second binding body 6. Figure 35 The card 20 is shown to be in contact with the second constraint body 6. In addition, at least one thrust spring 21 is provided on the base 3 or / and the helmet shell body 1 (see Figure 29 、 Figure 32 、 Figure 35 、 Figure 36 and Figure 37); one end of the thrust spring 21 abuts against the body of the card 20, and the other end of the thrust spring 21 abuts against the base 3 or against the helmet shell body 1. The elastic force of the thrust spring 21 always forces the card 20 to abut against the second constraint body 6, wherein the abutment between the thrust spring 21 and the card 20, the base 3 or the helmet shell body 1 includes direct abutment (such as Figure 29 、 Figure 32 and Figure 35 The two types of abutment are direct abutment (shown in the figure) and indirect abutment implemented through an intermediate piece (not shown in the figure). When the jaw guard 2 rotates and drives the second constraint body 6 to rotate, causing the first slot 6a or the second slot 6b to come into contact with the thrust structure 20a of the inserting card 20, the body of the inserting card 20 will move toward or away from the fixed axis O1, thereby generating a certain resistance torque to prevent accidental rotation of the jaw guard 2, thereby improving the reliability and safety of the helmet. It is particularly important to point out here that the thrust spring 21 and the lock tooth spring 17c can be used interchangeably, that is, the thrust spring 21 can be used as the lock tooth spring 17c, and the lock tooth spring 17c can also be used as the thrust spring 21: if the thrust spring 21 is also used as the lock tooth spring 17c, then the thrust spring 21 can take on the two functional tasks of locking the shield 4 and locking the jaw guard 2. Similarly, when the lock tooth spring 17c is also used as the thrust spring 21, then the lock tooth spring 17c can also take on the two functional tasks of locking the shield 4 and locking the jaw guard 2.

[0098] The present invention is to prevent the jaw guard 2 from hitting the shield 4 in the fully buckled position when returning from the half-helmet structure position to the full-helmet structure position (see Figure 26 ), an inner snap structure 20b is provided on the body of the card inserting 20, and an outer snap structure 17d is provided on the body of the inner snap teeth 17b (such as Figure 29 、 Figure 32 、 Figure 35 and Figure 36 As shown in the figure), when the card 20 moves away from the motion matching sub-fixed axis O1, the inner snap structure 20b on the card 20 body can touch the outer snap structure 17d on the inner snap tooth 17b body, thereby driving the inner snap tooth 17b to produce an unlocking displacement action to disengage from the outer snap tooth 17a, and then driven by the power spring 18 to drive the rack 17 through the driving gear 16, and then drive the shield 4 to make an opening action, thereby preventing the jaw guard 2 from hitting and striking the shield 4 when it is seated in the full helmet structure position, thereby improving the safety of the helmet. Figure 26 (a) to Figure 26(b) shows the process state in which the chin guard 2 is returning from the half-helmet structure position to the full-helmet structure position. During this period, the inner latching tooth 17b completes the unlocking displacement action of disengaging from the outer latching tooth 17a, and the shield 4 completes the opening action driven by the power spring 18, the drive gear 16 and the rack 17.

[0099] Furthermore, in order to reliably ensure that the jaw guard 2 does not touch the shield 4 when it is seated in the full helmet structure, the present invention provides an inclined top opening structure 20c ( Figure 13 、 Figures 27 to 36 The situation shown is an example in which the top opening structure 20c is provided on the card body 20), and a top inclined surface 17e corresponding to the top opening structure 20c is provided on the body of the rack 17 (as shown in FIG. Figure 13 、 Figures 28 to 35 When the shield 4 is in the buckled-down state, if the card 20 is displaced away from the fixed axis O1 of the motion mating pair, the lifting structure 20c can contact the lifting inclined surface 17e, and this contact behavior can generate a lifting displacement action that causes the shield 4 to be lifted. Figure 37 The illustrated state shows the situation where the lifting structure 20c on the card insertion 20 lifts the lifting slope 17e on the rack 17, causing the lower edge 4b of the shield 4 to separate from the jaw guard 2. It should be noted that the lifting slope 17e described in the present invention can have either a planar or curved structure, with a planar structure being the simplest.

[0100] In order to effectively remove the mist formed in the protective shield 4 due to the wearer's breathing, the present invention can adopt the following countermeasures in terms of structural design: the outer engaging teeth 17a include two concave tooth grooves, and the inner engaging teeth 17b include at least one convex protrusion; or the inner engaging teeth 17b include two concave tooth grooves, and the outer engaging teeth 17a include at least one convex protrusion. When these protrusions are engaged with the tooth grooves, the locking mechanism is in a locking state, wherein when the locking mechanism is in the locking state: ① In the case where the outer engaging teeth 17a include two concave tooth grooves and the inner engaging teeth 17b include at least one convex protrusion, when the tooth groove farther from the fork handle 2a of the jaw guard 2 has a protrusion engaged therewith, the lower edge 4b of the protective shield 4 is completely engaged with the jaw guard 2, and when the tooth groove farther from the fork handle 2a of the jaw guard 2 has no protrusion engaged therewith, the lower edge 4b of the protective shield 4 is completely engaged with the jaw guard 2, and when the tooth groove farther from the fork handle 2a of the jaw guard 2 has no protrusion engaged therewith, the lower edge 4b of the protective shield 4 is completely engaged with the jaw guard 2. A breathable gap 17f appears between the lower edge 4b of the shield 4 and the jaw guard 2; ② When the inner tooth 17b includes two concave tooth grooves and the outer tooth 17a includes at least one convex protruding tooth, when a protruding tooth appears in the tooth groove closer to the fork handle 2a of the jaw guard 2 and engages with it, the lower edge 4b of the shield 4 is completely fastened to the jaw guard 2, and when no protruding tooth appears in the tooth groove closer to the fork handle 2a of the jaw guard 2 and engages with it, a breathable gap 17f appears between the lower edge 4b of the shield 4 and the jaw guard 2. Figure 31 and Figure 32 、 Figure 38 and Figure 39 The situation shown is that there is a breathable gap 17f between the shield 4 and the jaw guard 2. In this case, the fresh air outside the helmet can be used to remove the fog inside the helmet to avoid it obstructing the vision, which is also conducive to improving safety when wearing a helmet while driving.

[0101] In order to effectively eliminate the gap between the kinematic fit of the first restraining body 5 and the second restraining body 6, and to improve the motion stability of the jaw guard 2 during the transition of its posture, the present invention can provide an arc-shaped stabilization structure 20d on the inserting card 20. The stabilization structure 20d is provided at the top of the inserting card 20 and is arranged in an inverted arch with the arc opening opening outward (see Figure 13 、 Figure 35 and Figure 36 ), when the card 20 is in the stage of being completely out of the first card slot 6a and the second card slot 6b on the second constraint body 6, the arc surface of the anti-bow layout of the stabilization structure is in contact with the second constraint body 6 (at Figure 35In the illustrated scenario, the stabilizing structure 20d of the card insert 20 is in contact with the main body of the second constraint 6. This contact, along with the compressive force of the thrust spring 21, eliminates the gap in the kinematic mating pair, while simultaneously increasing its support rigidity. This stabilizes the movement of the second constraint 6, or in other words, reduces or even eliminates the sway and swing amplitude of the second constraint 6. With this type of layout, the stabilizing effect of the stabilizing structure 20d (and, of course, the thrust spring 21) is even more pronounced when the contact structure A of the kinematic mating pair, in which the second constraint 6 and the first constraint 5 participate, has a shorter axial distribution length.

[0102] In order to enable the chin guard 2 to automatically flip to the half-helmet structure position when it is opened, so as to help the driver easily and safely realize the transformation of the chin guard 2 from the full-helmet structure position to the half-helmet structure position during driving, a passive tooth 6c can be provided on the second restraining body 6, and a fixed-axis rotatable active gear 22 can be provided on the base 3, the helmet shell body 1 or the first restraining body 5. The active gear 22 is kept in meshing state with the passive tooth 6c on the second restraining body 6 (such as Figure 40 As shown); a torsion spring 23 is also provided, one end of which rests on the driving gear 22 and the other end rests on the base 3, the helmet shell body 1, or the first restraining body 5. Under the action of the torsion spring 23, the driving gear 22 can generate a fixed-axis rotation around its own axis. The rotation of the driving gear 22 drives the second restraining body 6 to rotate around the fixed axis O1 of the kinematic matching pair through the passive gear 6c. As a result, under the drive of the torsion spring 23, the chin guard 2 and its fork handle 2a will automatically open and flip to the half-helmet structure position. The present invention, by providing the driving gear 22 and the passive gear 6c on the second restraining body 6, and supplemented by the torsion spring 23, automatically opens the chin guard 2 and converts it from the full-helmet structure position to the half-helmet structure position, thereby achieving the purpose of convenient operation. This function reduces the time and amplitude of manual conversion of the chin guard 2, thereby reducing the chance of safety accidents. In this sense, it can indeed increase the safety of helmet use.

[0103] Furthermore, the driving gear 22 has and only has one special-shaped tooth 22a, wherein the tooth width of the special-shaped tooth 22a is greater than the tooth width of other normal teeth of the driving gear 22 (such as Figure 40As shown, all teeth of the driving gear 22, including the special-shaped teeth 22a, are distributed throughout a complete 360° circumference. When the chin guard 2 flips from the full-face configuration to the half-face configuration, the driving gear 22 completes a full rotation. This arrangement allows for a recess in the second restraining body 6 that matches the special-shaped teeth 22a. This wider recess can be used as a grip for designing other devices, such as a device that can moderately retain the chin guard 2 in the full-face configuration or / and the half-face configuration.

[0104] In order to prevent the shield 4 from being accidentally opened due to collision or unintentional touch when the shield 4 is fully fastened to the jaw guard 2, the present invention can provide a locking and unlocking mechanism for the shield 4 at the lower edge 4b of the shield 4 and on the main body of the jaw guard 2, thereby improving the safety of helmet use. The locking and unlocking mechanism of the present invention includes an inner buckle structure B provided at the lower edge 4b of the shield 4 and an outer buckle structure C provided on the main body of the jaw guard 2, wherein the inner buckle structure B and the outer buckle structure C correspond to each other; wherein the inner buckle structure B is a protruding structure relative to the shield 4 (such as Figure 41 As shown) or in the shape of a flange structure (not shown in the figure), in particular, the inner buckle structure B includes a locking structure 4d (see Figure 42 The outer buckle structure C includes a bougie 24 that can be forced to give way, a lock hook 24a opened on the bougie 24 (see Figure 41 and Figure 42 ), the lock hook 24a is wedge-shaped, and the lock hook 24a can be a separate component and connected to the body of the bougie 24 (not shown in the figure), especially the lock hook 24a and the bougie 24 can be made into an integral structure (such as Figure 41 and Figure 42 Here, the "bougie 24 that can be forced to give way" refers to the bougie 24 being able to make a displacement movement when it is touched or manipulated by the outside world. The displacement movement includes the bougie 24 making way by using its own elastic deformation when it is pressed, and also includes the bougie 24 making way by using displacement forms such as movement or swinging when it is pressed. Figures 41 to 42In the embodiment shown, the bougie 24 is achieved by swinging around a rotating pin 24b on its body to make a displacement action, and the rotating pin 24b is rotatably assembled on a base 25, wherein the base 25 is fastened to or integrally made on the body of the jaw guard 2; in addition, the locking and unlocking mechanism of the present invention further includes a first unlocking key 26 and / or a second unlocking key 27, and the first unlocking key 26 and the second unlocking key 27 are both arranged on the body of the jaw guard 2 and they can both serve as actuating members for unlocking the shield 4, wherein the first unlocking key 26 is arranged adjacent to the bougie 24 and can touch the bougie 24 during its actuation, and the second unlocking key 27 is arranged at the lower part of the jaw guard 2, and it can unlock the jaw guard 2 in the full helmet structure position, and can control the bougie 24 in a linkage manner during its actuation. When the first unlocking button 26 or the second unlocking button 27 touches the bougie 24, they can cause the bougie 24 to give way by pressing or pulling; here, the best layout strategy of the first unlocking button 26 and the second unlocking button 27 is that their structures intersect with the symmetry plane P of the helmet shell body 1 (or their structures intersect with the intersection line S). In addition, the "second unlocking button 27 can unlock the jaw guard 2 in the full helmet structure position" means that the second unlocking button 27 can generate a displacement action during its actuation and directly unlock the locking mechanism between the jaw guard 2 and the helmet shell body 1 through the displacement action or indirectly unlock the locking mechanism between the jaw guard 2 and the helmet shell body 1 through other intermediate parts, so that the jaw guard 2 can be opened relative to the helmet shell body 1 without hindrance. Flipping action; the "second unlocking button 27 is arranged at the lower part of the chin guard 2" means that when the wearer wears the helmet normally and the chin guard 2 is in the full helmet structure position, the second unlocking button 27 is within the area of the lowermost end part of the chin guard 2 body (including its vicinity); the present invention can use manual action to operate the first unlocking button 26 and the second unlocking button 27 to cause them to produce a certain movement displacement, and after they complete their actuation tasks, they can still be manually operated to return to their original positions, or use their own elastic restoring force to return to their original positions; in particular, the present invention can also use the action of spring elastic force to allow the first unlocking button 26 and the second unlocking button 27 to automatically return to their original positions after their actuation tasks are completed. For this purpose, a first return spring 28a can be provided (see Figure 41 and Figure 42 ) and a second return spring (not shown in the figure) to help them achieve automatic reset, wherein the first return spring 28a is used to reset the first unlocking key 26, and the second return spring is used to reset the second unlocking key 27. One end of the first return spring 28a is against the first unlocking key 26 and the other end of the first return spring 28a is against the body of the jaw guard 2 (as shown in the figure). Figure 42As shown), one end of the second return spring abuts against the second unlocking key 27 and the other end of the second return spring abuts against the body of the jaw guard 2 (not shown in the figure); when the jaw guard 2 is in the full helmet structure position and the shield 4 is completely fastened to the jaw guard 2 (as shown in the figure), the second return spring abuts against the second unlocking key 27 and the other end of the second return spring abuts against the body of the jaw guard 2 (not shown in the figure); Figure 42 As shown in FIG. 1 , the locking and unlocking mechanism of the shield 4 can have three working conditions: a) when both the first unlocking key 26 and the second unlocking key 27 are not touched, the lock hook 24a on the bougie 24 is in the original position, and the lock hook 24a in the original position can hook the locking structure 4d of the inner buckle structure B and lock the shield 4 accordingly; Figure 42 (a) shows exactly this situation. At this time, the first unlocking button 26 and the second unlocking button 27 are both in their original positions. It should be noted that the first return spring 28a can help the first unlocking button 26 return to its original position or keep the first unlocking button 26 in its original position under normal circumstances; b) when the first unlocking button 26 is actuated (that is, when the first unlocking button 26 is subjected to external pressure, such as when the helmet wearer presses it with his hand), the first unlocking button 26 can be displaced and touch the bougie 24, and this contact behavior can cause the lock hook 24a on the bougie 24 to move out of its original position, thereby unlocking the shield 4. Figure 42 (b) shows exactly this situation. At this time, the first unlocking button 26 is actuated by an external force and thus moves away from its original position after overcoming the elastic force of the first return spring 28a (that is, the first unlocking button 26 is actuated, for example, the first unlocking button 26 is pressed by the finger of the helmet wearer and moves). Then, the first unlocking button 26 touches the bougie 24, prompting the bougie 24 to make a move (that is, the lock hook 24a no longer hooks the locking structure 4d of the inner buckle structure B). However, at this time, the second unlocking button 27 can still be in its original position when not affected by external forces; c) When the second unlocking button 27 is actuated (that is, it is manipulated by the outside world, such as when the helmet wearer pulls it with his finger), the second unlocking button 27 can be actuated and thus drive the bougie 24 in conjunction with the driving action, and the lock hook 24a on the bougie 24 can be moved away from its original position, thereby unlocking the shield 4. Figure 42 (c) shows this situation. At this time, the second unlocking button 27 is manually pulled out of its original position and drives the bougie 24 through an intermediate hook 29, thereby forcing the bougie 24 to move out of its original position. However, at this time, the first unlocking button 26 can remain in its original position without being pressed. It is worth noting that the second unlocking button 27 in the present invention can be used in the above-mentioned Figure 42(c) shows the linkage mode of the hook 29 to indirectly drive the bougie 24. In addition, it can also be driven by directly touching the bougie 24 through its main body structure (not shown in the figure). Figure 41 and Figure 42 In the embodiment (c) shown, the second unlocking key 27 is actuated by a swinging displacement around a rotating shaft 27a, wherein the rotating shaft 27a is constrained by a seat hole 30a on a base plate 30. The seat hole 30a can be a complete circular hole structure or a partial circular hole structure. In addition, the base plate 30 is fastened to the body of the jaw guard 2 or the base plate 30 and the body of the jaw guard 2 are made of an integral structure. In addition, the first unlocking key 26 can drive the bougie 24 by a direct touch (such as Figure 42 As shown in the figure), it can also be driven by indirect contact, that is, by means of other parts or mechanisms (not shown in the figure). It should be noted that the actuation action of the first unlocking key 26 and the actuation action of the second unlocking key 27 in the present invention can be performed separately or in combination, that is, the actuation actions of the first unlocking key 26 and the second unlocking key 27 to allow the bougie 24 to complete the yielding action do not interfere with each other. It should also be noted that in order to allow the bougie 24 to reliably return to its original position when it is not controlled by the first unlocking key 26 and / or the second unlocking key 27, the present invention can also be provided with a third return spring 28b (as shown in the figure). Figure 41 and Figure 42 As shown), one end of the third return spring 28b rests on the bougie 24, and the other end thereof may rest directly or indirectly on the body of the jaw guard 2; it should also be noted that the retractor 29 may be a part having an elastomeric structure, so that when the first unlocking button 26 is pressed by hand but the second unlocking button 27 is not touched, the deformation generated by the elasticity of the retractor 29 can be used to accommodate the displacement action of the bougie 24, thereby avoiding interference between the first unlocking button 26 and the retractor 29 and preventing the bougie 24 from achieving the displacement action; Figure 41 and Figure 42 In the embodiment shown, the pull hook 29 drives the bougie 24 by hooking the pull hole 24c on the bougie 24 body. The pull hole 24c is preferably a waist-shaped structure because such a structure can form a larger redundant space and can more effectively avoid interference. In addition, the lock hook 24a can have a variety of shapes, such as the wedge-shaped structure mentioned above (such as Figure 41In addition, in order to ensure that the locking hook 24a has a consistent position when assembled (especially in batches), the present invention can also provide a positioning structure 2b on the body of the jaw guard 2 that can limit the position (see Figure 42 ), the positioning structure 2b can effectively ensure that the bougie 24 is in the correct original position during assembly. It is particularly worth noting that the first unlocking key 26 of the present invention can be arranged at the upper lip edge of the jaw guard 2. The advantage of such an arrangement is that when the shield 4 is completely fastened to the jaw guard 2, the first unlocking key 26 is located adjacent to the inner buckle structure B of the shield 4. In this way, when it is necessary to use fresh air outside the helmet to remove the fog inside the helmet to avoid obstructing the vision, the shield 4 can be unlocked by manually pressing the first unlocking key 26 to trigger the bougie 24 to complete the giving way action. At the same time, the shield 4 can be pushed by a finger to force it to produce a slight displacement, thereby creating a breathable gap 17f between the lower edge 4b of the shield 4 and the jaw guard 2 (see Figure 31 、 Figure 32 、 Figure 38 and Figure 39 ), thereby improving safety when driving with a helmet.

[0105] The outstanding advantage of the present invention compared with the prior art is that it adopts the structural form of setting a first constraint body 5 and a second constraint body 6 to form a kinematic matching pair, and utilizes their contact structure A distributed on a cylindrical surface to form a geometric constraint structure, thereby achieving the constraint of the second constraint body 6 and then achieving the constraint that the fork handle 2a of the jaw guard 2 can make a fixed-axis rotation around the fixed axis O1 of the kinematic matching pair, and further, under the support of the displacement obtaining mechanism, it can also constrain the second constraint body 6 and then constrain the fork handle 2a of the jaw guard 2 to achieve an opening and closing displacement action of moving away and approaching along the fixed axis O1 relative to the symmetry plane P of the helmet shell body 1, thereby achieving The advantages of this design are: on the one hand, the chin guard 2 can be retracted relative to the helmet shell 1 when in the full-face helmet configuration, thereby achieving a favorable aerodynamic shape and reducing the helmet's bulk, thereby improving the helmet's comfort and storage. Furthermore, the retracted structure of the chin guard 2a in the full-face helmet configuration transfers impact forces directly to the helmet shell 1, thereby enhancing the helmet's safety and reliability. On the other hand, when the chin guard 2 is flipped, the chin guard 2a can be extended outward, thereby avoiding the restraint of the helmet shell 1 and preventing the chin guard 2 from transitioning between the full-face and half-face helmet configurations. Needless to say, the present invention eliminates the abrupt, protruding chin guard 2a layout of conventional variable chin guard helmets. While retaining the unique advantages of flexible deformation options inherent to variable-structure chin guard helmets, it also effectively reduces airflow whistling and reduces the helmet's bulk. Furthermore, it increases the supporting rigidity of the chin guard 2a, thereby enhancing the helmet's safety and reliability.

[0106] The above embodiments are only some preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, all equivalent changes made in accordance with the structure, shape, and principle of the present invention should be included in the scope of protection of the present invention.

Claims

1. A helmet with a fixed-axis rotating variable jaw guard, comprising a helmet shell, a jaw guard, two bases, and a shield, wherein the helmet shell has a symmetrical plane, the two bases are separated by the symmetrical plane and are disposed on opposite sides of the helmet shell, and the two bases are fastened to the helmet shell or are integrally formed with the helmet shell, the jaw guard having two fork handles disposed on opposite sides of the helmet shell; and characterized in that: Two first constraint bodies are provided, and these two first constraint bodies are separated by the symmetry plane and are arranged on both sides of the helmet shell body. The first constraint body is fastened to the base and / or the helmet shell body, or the first constraint body and the base and / or the helmet shell body are made as an integral structure; a second constraint body is provided on each of the fork handles, and this second constraint body is fastened to the fork handle or the second constraint body and the fork handle are made as an integral structure; the first constraint body and the second constraint body arranged on the same side of the helmet shell body together constitute at least one pair of motion matching pairs, and these motion matching pairs have a fixed axis that is stationary relative to the helmet shell body, and in each pair of motion matching pairs, the contact structure of the first constraint body and the second constraint body participating in the formation of the motion matching pair is composed of a collection of geometric elements distributed at equal distances from the fixed axis, and the second constraint body can rotate. and under the constraint of the first constraint body, the rotational motion is manifested as a fixed-axis rotation around the fixed axis; in addition, a displacement obtaining mechanism is provided, which, in response to the jaw guard being in the process stage of being opened and separated from its full-face helmet structure position, can generate an opening displacement movement that drives the second constraint body away from the symmetric plane of the helmet shell body, and in response to the jaw guard being in the process stage of returning to its full-face helmet structure position, can generate a closing displacement movement that drives the second constraint body close to the symmetric plane of the helmet shell body, and at the same time, during the period when the second constraint body is in the opening displacement movement and the period when it is in the closing displacement movement, the first constraint body forms an axial constraint behavior on the second constraint body, and the characteristic of this axial constraint behavior is that it causes the opening displacement movement and the closing displacement movement of the second constraint body to be manifested as a linear displacement along the direction of the fixed axis of the motion matching pair; The displacement obtaining mechanism is or includes a) a displacement obtaining mechanism; a) The first constraint body and the second constraint body are arranged on the same side of the helmet shell body in response to each other, and a first hole is provided on the first constraint body, the base or the helmet shell body, and a support column corresponding to the first hole is provided on the second constraint body or / and the fork handle; or / and, the first constraint body and the second constraint body are arranged on the same side of the helmet shell body in response to each other, a first hole is provided on the second constraint body or / and the fork handle, and a support column corresponding to the first hole is provided on the first constraint body, the base or the helmet shell body; the first hole or / and the support column include at least one first inclined surface in the shape of a slope relative to the symmetry surface of the helmet shell body, and in response to the chin guard being opened, separated from or returned to its full helmet structure position, the support column and the first hole are in contact at the first inclined surface, and through this contact behavior, the second constraint body can generate a displacement action away from or close to the symmetry surface of the helmet shell body, thereby forming a displacement acquisition mechanism.

2. The fixed-axis rotating variable jaw guard helmet according to claim 1, characterized in that: The displacement obtaining mechanism is or includes c) a displacement obtaining mechanism: c) a displacement obtaining mechanism can replace a) a displacement obtaining mechanism; c) The first constraint body and the second constraint body are arranged on the same side of the helmet shell body in response to each other, and a groove-shaped track groove is provided on the first constraint body, the base or the helmet shell body, and a load-bearing pin is provided on the second constraint body and / or the fork handle, and the load-bearing pin is inserted into the track groove and constrained by the track groove; or, the first constraint body and the second constraint body are arranged on the same side of the helmet shell body in response to each other, a groove-shaped track groove is provided on the second constraint body and / or the fork handle, and a load-bearing pin is provided on the first constraint body, the base or the helmet shell body, and the load-bearing pin is inserted into the track groove and constrained by the track groove; in addition, a first inclined surface is opened in the track groove, and in response to the process stage of the chin guard being opened and separated from or returned to the full helmet structure position, the load-bearing pin and the track groove have a contact behavior at the first inclined surface, and through this contact behavior, the second constraint body can generate a displacement action away from or close to the symmetry plane of the helmet shell body, thereby forming a displacement acquisition mechanism.

3. The fixed-axis rotating variable jaw guard helmet according to claim 2, characterized in that: A load-bearing member is arranged on the second constraint body and / or the fork handle, and this load-bearing member is fastened to or made into an integral structure on the second constraint body and / or the fork handle; an energy storage spring is arranged between the load-bearing member and the first constraint body, or between the load-bearing member and the base support, or between the load-bearing member and the helmet shell body, and one end of the energy storage spring rests on the load-bearing member, and the other end of the energy storage spring rests on the first constraint body, the base support or the helmet shell body.

4. The fixed-axis rotating variable jaw guard helmet according to claim 3, characterized in that: A first hole is provided on and only on the first constraint body, and a push rod corresponding to the first hole is provided on and only on the second constraint body, or a first hole is provided on and only on the second constraint body, and a push rod corresponding to the first hole is provided on and only on the first constraint body; the number of the first hole and the push rod arranged in correspondence on the same side of the helmet shell body is greater than or equal to three, and these first hole and the push rod are paired one by one, and the first inclined surface of each pair of first hole and push rod contains an equivalent radius with the fixed axis of the motion matching pair as the measurement starting point, and the larger the equivalent radius, the smaller the value of the equivalent slope of the first inclined surface.

5. The fixed-axis rotating variable jaw guard helmet according to claim 4, characterized in that: For all paired first slots and push rods, the equivalent radius of the first inclined surface of each pair is not equal to each other, and when the second constraint body rotates around the fixed axis of its motion matching pair, the contact behavior of each paired push rod and first slot at the equivalent radius of their respective first inclined surfaces all presents a timing pattern of synchronous contact and synchronous separation.

6. The fixed-axis rotating variable jaw guard helmet according to claim 5, characterized in that: A second hole slot is provided on the first constraint body and the number of the second hole slots is consistent with the number of the struts provided only on the second constraint body, or a second hole slot is provided on the second constraint body and the number of the second hole slots is consistent with the number of the struts provided only on the first constraint body; the second hole slots and the struts are paired in a one-to-one correspondence, and the paired second hole slots and the struts include a second inclined surface that is sloped relative to the symmetrical surface of the helmet shell body; in response to the process stage of the jaw guard flipping out of or approaching to its half-helmet structure position, the paired struts and the second hole slots are in contact with each other at their second inclined surfaces, and these contact behaviors can prompt the second constraint body to produce a displacement action close to or away from the symmetrical surface of the helmet shell body.

7. The fixed-axis rotating variable jaw guard helmet according to claim 6, characterized in that: A buckle is provided on the first restraint body, the base or the helmet shell body, and a tongue corresponding to the buckle is provided on the load-bearing member. When the chin guard is in the full helmet structure position or / and the half helmet structure position and is observed along the direction of the fixed axis of the motion fit pair toward the symmetry plane of the helmet shell body: the buckle is located farther away from the symmetry plane of the helmet shell body than the tongue, and when they are projected onto the symmetry plane of the helmet shell body, the projection of at least one buckle intersects with the projection of the tongue.

8. The fixed-axis rotating variable jaw guard helmet according to claim 7, characterized in that: There are three first hole slots arranged on the same side of the helmet shell body. These three first hole slots all include a first inclined surface. Starting from the slope vertices corresponding to the equivalent radius of each first inclined surface, perpendicular lines are drawn to the fixed axis of the motion matching pair, and these perpendicular lines are projected onto the symmetry plane of the helmet shell body. The minimum angles formed between the projection lines of the three perpendicular lines obtained on the symmetry plane are not less than 90°. At the same time, the sum of the three minimum angles formed between the projection lines of the three perpendicular lines obtained is always maintained at 360°.

9. The fixed-axis rotating variable jaw guard helmet according to claim 8, characterized in that: The energy storage spring is a conical spring, and the conical energy storage spring and the fixed axis of the kinematic matching pair are coaxially arranged.

10. The fixed-axis rotating variable jaw guard helmet according to claim 9, characterized in that: The load-bearing member and / or its connecting accessories are made of magnetically attractive materials or are magnets, and the helmet shell body, the base or the first restraint body are provided with magnets or magnetically attractive parts that correspond to them and can together form a magnetic pair.

11. The fixed-axis rotating variable jaw guard helmet according to any one of claims 1 to 10, characterized in that: The shield includes two supporting sides, which are separated by the symmetrical plane and are located on both sides of the helmet shell body; at least one base includes an outer cover and a bottom cover, and a driving gear that can rotate on a fixed axis, a rack engaged with the driving gear, and a power spring that can drive the driving gear to rotate are equipped on this base or the helmet shell body. The rack is connected to the supporting sides of the shield, and an arc-shaped outer guide groove is provided on the outer cover and / or the helmet shell body, and an arc-shaped inner guide groove is provided on the bottom cover and / or the helmet shell body. The outer guide groove and the inner guide groove together constitute a constraint guide rail, and the constraint guide rail is used to constrain the position and posture of the rack.

12. The fixed-axis rotating variable jaw guard helmet according to claim 11, characterized in that: A locking tooth mechanism is arranged on the base and / or the helmet shell body, and the locking tooth mechanism includes an external tooth arranged on the rack, an internal tooth equipped on the base or the helmet shell body, and a locking tooth spring. The body of the internal tooth is constrained by the base and / or the helmet shell body and under its constraint, the movement of the internal tooth is expressed in the form of linear displacement or swinging displacement, wherein the elastic force of the locking tooth spring always forces the internal tooth to press against the external tooth.

13. The fixed-axis rotating variable jaw guard helmet according to claim 12, characterized in that: A first card slot is provided on the second constraint body to respond to the jaw guard being in the full helmet structure position, and a second card slot is provided on the second constraint body to respond to the jaw guard being in the half helmet structure position; an insertion card including an inclined thrust structure is provided on the base support and / or the helmet shell body, and the insertion card is in contact with the second constraint body; in addition, at least one thrust spring is provided on the base support and / or the helmet shell body, one end of the thrust spring is in contact with the body of the insertion card, and the other end of the thrust spring is in contact with the base support or the helmet shell body, and the elastic force of the thrust spring always forces the insertion card to be in contact with the second constraint body; when the jaw guard rotates and drives the second constraint body to rotate so that the first card slot or the second card slot thereon comes into contact with the inclined structure of the insertion card, the body of the insertion card will produce a displacement action close to or away from the fixed axis of the motion matching pair.

14. The fixed-axis rotating variable jaw guard helmet according to claim 13, characterized in that: An inner snap structure is provided on the body of the card insertion, and an outer snap structure is provided on the body of the inner snap tooth. When the card insertion moves away from the fixed axis of the motion matching pair, the inner snap structure of the card insertion body can touch the outer snap structure on the body of the inner snap tooth and drive the inner snap tooth to produce an unlocking displacement action to disengage from the outer snap tooth.

15. The fixed-axis rotating variable jaw guard helmet according to claim 14, characterized in that: A sloped top-opening structure is provided on the body of the insertion card or the body of the inner card tooth, and a lifting slope corresponding to the top-opening structure is provided on the body of the rack. When the shield is in the buckled-down state, if the insertion card makes a displacement action away from the fixed axis of the motion matching pair, the top-opening structure can touch the lifting slope, and this contact behavior can prompt the shield to make a lifting displacement action along the opening direction relative to the helmet shell body.

16. The fixed-axis rotating variable jaw guard helmet according to claim 15, characterized in that: The outer card tooth includes two concave tooth grooves and the inner card tooth includes at least one convex protruding tooth, or the inner card tooth includes two concave tooth grooves and the outer card tooth includes at least one convex protruding tooth. When these protruding teeth and the tooth grooves are engaged, the locking tooth mechanism is in a locking tooth state. In the locking tooth state stage of the locking tooth mechanism: when the outer card tooth includes two concave tooth grooves and the inner card tooth includes at least one convex protruding tooth, when a protruding tooth appears in the tooth groove farther away from the jaw guard fork handle and engages with it, the jaw guard handle is engaged. The lower edge of the cover is completely engaged with the jaw guard, and when there is no protruding tooth in the tooth groove farther away from the jaw guard fork handle to engage with it, a breathable gap appears between the lower edge of the cover and the jaw guard; in the case where the inner teeth include two concave tooth grooves and the outer teeth include at least one convex tooth, when there is a protruding tooth in the tooth groove closer to the jaw guard fork handle to engage with it, the lower edge of the cover is completely engaged with the jaw guard, and when there is no protruding tooth in the tooth groove closer to the jaw guard fork handle to engage with it, a breathable gap appears between the lower edge of the cover and the jaw guard.

17. The fixed-axis rotating variable jaw guard helmet according to claim 16, characterized in that: The card insertion has an arc-shaped stabilizing structure, which is arranged at the top end of the card and has an inverse-bow layout with the arc opening opening outward. When the card insertion is completely out of the first card slot and the second card slot on the second constraint body, the arc surface of the inverse-bow layout of the stabilizing structure is in contact with the second constraint body.

18. The fixed-axis rotating variable jaw guard helmet according to any one of claims 1 to 10, characterized in that: A passive tooth is provided on the second constraint body, and a driving gear that can rotate about a fixed axis is provided on the base support, the helmet shell body or the first constraint body, and the driving gear maintains an engagement state with the passive tooth on the second constraint body; in addition, a torsion spring is provided, one end of the torsion spring rests on the active tooth and the other end rests on the base support, the helmet shell body or the first constraint body, and the active gear can generate fixed axis rotation under the action of the torsion spring, and the rotation of the active gear drives the second constraint body to rotate around the fixed axis of the motion matching pair through the passive tooth.

19. The fixed-axis rotating variable jaw guard helmet according to claim 18, characterized in that: The driving gear has one and only one special-shaped tooth, the tooth width of which is greater than the tooth width of the other normal teeth of the driving gear. All the teeth of the driving gear, including the special-shaped tooth, are distributed in a complete 360° circumference, and when the chin guard is flipped from the full-helmet structure position to the half-helmet structure position, the driving gear rotates a full circle.

20. The fixed-axis rotating variable jaw guard helmet according to any one of claims 1 to 10, characterized in that: A shield locking and unlocking mechanism is provided at the lower edge of the shield and on the main body of the jaw guard. The shield locking and unlocking mechanism includes an inner buckle structure provided at the lower edge of the shield and an outer buckle structure provided on the main body of the jaw guard. The inner buckle structure includes a locking structure, and the outer buckle structure includes a bougie that can be forced to give way and a lock hook provided on the bougie. In addition, the shield locking and unlocking mechanism also includes a first unlocking key and / or a second unlocking key. The first unlocking key and the second unlocking key are arranged on the main body of the jaw guard and can both serve as an actuation for unlocking the shield. The invention relates to a component wherein a first unlocking button is disposed adjacent to a bougie and can contact the bougie during actuation, and a second unlocking button is disposed at a lower portion of the chin guard and can unlock the chin guard in a full-face helmet configuration and can be linked to operate the bougie during actuation; when the chin guard is in the full-face helmet configuration and the shroud is fully engaged with the chin guard, the shroud locking and unlocking mechanism can have three operating conditions: a) when neither the first unlocking button nor the second unlocking button is actuated, the locking hook on the bougie is in an original position, and the locking hook in the original position can engage with a locking structure of the inner buckle structure to thereby lock the shroud; b) when the first unlocking button is operated and during its actuation, the first unlocking button can touch the bougie and, through the touching action, can cause the locking hook of the bougie to move out of its original position, thereby unlocking the shield; c) When the second unlocking button is operated, the second unlocking button can drive the bougie and, through the driving action, can cause the lock hook of the bougie to leave its original position, thereby unlocking the shield.

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