CN219214946U - Safety belt retractor and safety belt - Google Patents

Abstract

A seat belt retractor and a seat belt, the seat belt retractor includes a motor unit, a spool unit, and a control unit; the motor unit is coaxially and directly connected with the reel unit, and the control unit controls the motor unit to rotate forwards or reversely at a required time point; the motor unit comprises a rotor and a speed reducing mechanism coaxially connected with the rotor through a first connecting piece; the output end of the speed reducing mechanism is coaxially connected with the first end of the force limiting rod of the reel unit through a ratchet pawl mechanism; when the motor unit rotates positively, the first end of the force limiting rod obtains the output of the speed reducing mechanism through the ratchet pawl mechanism, and the reel unit obtains the torque of forward rotation transmitted by the speed reducing mechanism through the force limiting rod, so that the pretension of the safety belt retractor is realized; when the motor unit rotates reversely, a ratchet and a pawl in the ratchet pawl mechanism are separated from contact, so that the force limiting rod does not rotate reversely.

Description

Safety belt retractor and safety belt

Technical Field

The application relates to the technical field of vehicle safety belts, in particular to a safety belt retractor and a safety belt.

Background

The safety belt retractor is one of core components of a vehicle safety system, and under the action of the safety belt retractor, when a vehicle is not collided, the safety belt webbing can be stretched, so that passengers can freely adjust sitting postures; when the vehicle collides, the safety belt retractor is in a locking state immediately, and the safety belt webbing is driven to strongly tie up the protected passenger, so that the safety belt webbing is tightly tied on the seat, and the safety belt retractor plays a role in protecting the passenger.

Because the safety belt can be stretched when in collision, and the passenger is likely to have no preparation when in vehicle collision, the body of the passenger is likely to be far away from the backrest and is not firmly bound by the safety belt, the protection effect of the safety belt is obviously weakened when in collision under the posture.

In order to solve the problem, a pyrotechnic pretension force-limiting safety belt is generated, and the safety belt is ignited by an ignition device at the moment of collision of a vehicle, the pyrotechnic device is started to explode, a plurality of bullet-shaped steel balls are launched, and a retractor is retracted to a tightly-restrained state, so that an occupant is in a tightly-restrained state with a seat instantaneously. The actively restrained seat belt is capable of tightening the seat belt webbing when an impending collision is predicted, and provides for occupant protection for the impending collision of the vehicle.

However, such actively restrained pyrotechnic belts have a single service life and must be replaced once the pyrotechnic device explodes, which obviously increases costs and is extremely inconvenient.

According to the technical scheme, the pre-tightening motor arranged on the retractor is matched with the early warning radar, and early warning is carried out in advance in an electric control mode, so that the retractor can perform various vibration actions under the non-collision condition to obtain the effect of keeping a driver alert and the like, and the application range of a safety belt system is further widened.

Under the prior art, the safety belt with the pre-tightening motor is generally characterized in that a direct current brush motor is arranged on a retractor, and the motor is generally arranged in parallel with a retractor body, so that the whole retractor is overlarge in size, and a proper installation space is difficult to obtain in an automobile.

Under the prior art, there is a strong need for a compact and convenient seatbelt retractor with a pretensioning motor for ease of installation and further improved active restraint systems for further occupant comfort and safety.

Disclosure of Invention

The embodiment of the application provides a safety belt retractor to solve the too big problem of pretension type safety belt retractor volume among the prior art, this application provides the embodiment and realizes pretension to the retractor through the limit force pole on reduction gears and the spool. The application also provides a safety belt comprising the safety belt retractor.

The embodiment of the application provides a seat belt retractor.

Optionally, the device comprises a motor unit, a reel unit and a control unit;

the motor unit is coaxially and directly connected with the reel unit, and the control unit controls the motor unit to rotate forwards or reversely at a required time point;

the motor unit comprises a rotor and a speed reducing mechanism coaxially connected with the rotor through a first connecting piece; the output end of the speed reducing mechanism is coaxially connected with the first end of the force limiting rod of the reel unit through a ratchet pawl mechanism;

when the motor unit rotates positively, the first end of the force limiting rod obtains the output of the speed reducing mechanism through the ratchet pawl mechanism, and the reel unit obtains the torque of forward rotation transmitted by the speed reducing mechanism through the force limiting rod, so that the pretension of the safety belt retractor is realized; when the motor unit rotates reversely, a ratchet and a pawl in the ratchet pawl mechanism are separated from contact, so that the force limiting rod does not rotate reversely.

Optionally, the motor unit is a brushless motor unit, and the brushless motor unit includes a stator;

the stator is provided with coils and iron core rings, and the coils are annularly distributed on the iron core rings; the stator is coaxial with the rotor and is positioned at the inner ring of the rotor; and the brushless motor unit drives the rotor to rotate at a high speed relative to the stator after receiving the signal of the control unit.

Optionally, the speed reducing mechanism comprises a first carrier, a second carrier and a planetary gear mechanism arranged between the first carrier and the second carrier;

the planetary gear mechanism comprises a sun gear and a planetary gear, and an inner gear is provided with the sun gear and the planetary gear; the first end of the first connecting piece is connected with the rotor of the brushless motor unit, and the second end of the first connecting piece is connected with the sun gear after penetrating through a first bearing hole in the center of the first carrier; the periphery of the sun gear is provided with a plurality of planet gears meshed with the sun gear; an inner gear is arranged on the outer ring of the planet wheel;

the center shaft of the planet wheel is provided with a first bearing hole with two ends respectively connected with the first bearing device and a second bearing hole of the second bearing device;

and the end face of the second carrier, which faces the outer side, is provided with a structure for connecting the ratchet and pawl mechanism.

Optionally, a fixing shaft extending towards the second carrier is arranged on the first carrier, and the fixing shaft is inserted into a fixing hole on the second carrier, so that the first carrier and the second carrier are combined into a whole.

Optionally, a first bearing is installed in a first bearing hole in the center of the first carrier, and a middle cylindrical surface of the first connecting piece is matched with the first bearing to obtain rotary support.

Optionally, the second carrier is centrally provided with a protrusion facing the direction of the first carrier, the protrusion being provided with a second bearing, the second bearing being fitted with a central hole provided in the motor housing, such that the second carrier obtains a rotational support.

Optionally, a structure for connecting the ratchet-pawl mechanism is arranged on the end face of the second carrier facing the outer side, the ratchet-pawl mechanism comprises a pawl retainer, the pawl is mounted on the pawl retainer, the brushless motor starts to rotate forward, and the process of driving the pawl of the ratchet-pawl mechanism to be meshed with the outer gear ring of the ratchet is realized through the following structure:

a pair of arc-shaped guide holes extending from the outer edge to the inner diameter direction are oppositely arranged at the position close to the outer edge of the pawl retainer, and two pawls are respectively arranged in the arc-shaped guide holes through first bosses arranged on the surfaces of the pawls; the pawl is provided with a first connecting hole, and a boss on the upper-stage transmission piece is inserted into the first connecting hole;

the brushless motor starts to rotate positively, and the pawl slides from a position close to the outer edge surface to a position close to the tail end of the arc-shaped guide hole with the inner diameter under the guidance of the arc-shaped guide hole, and is meshed with the ratchet wheel outer gear ring at the position.

Optionally, the pawl cage is provided with a central boss, and the boss is provided with a first chute; the clutch spring in a shape like a Chinese character 'ji' is clamped with the pawl retainer through the first chute, and the middle of the head part of the clutch spring is sleeved with a positioning boss arranged on the retainer and can be blocked by the positioning boss; when the brushless motor starts to rotate in the forward direction due to friction force generated by the clutch spring, the pawl holder is blocked from rotating or rotating slowly, and in the process, the pawl slides to the tail end position of the arc-shaped guide hole close to the inner diameter.

Optionally, the brushless motor starts to rotate reversely, so that the pawl of the ratchet pawl mechanism can be driven to be disengaged from the outer gear ring of the ratchet.

As described above, the seatbelt retractor according to the present embodiment includes the motor unit, the spool unit, and the control unit; the motor unit is coaxially and directly connected with the reel unit, and the control unit controls the motor unit to rotate forwards or reversely at a required time point; the motor unit comprises a rotor and a speed reducing mechanism coaxially connected with the rotor through a first connecting piece; the output end of the speed reducing mechanism is coaxially connected with the first end of the force limiting rod of the reel unit through a ratchet pawl mechanism; when the motor unit rotates positively, the first end of the force limiting rod obtains the output of the speed reducing mechanism through the ratchet pawl mechanism, and the reel unit obtains the torque of forward rotation transmitted by the speed reducing mechanism through the force limiting rod, so that the pretension of the safety belt retractor is realized; when the motor unit rotates reversely, a ratchet and a pawl in the ratchet pawl mechanism are separated from contact, so that the force limiting rod does not rotate reversely. Due to the adoption of the technical scheme that the motor unit and the reel unit are coaxially and directly connected, the whole mechanism is small in size, and a more proper installation position can be obtained.

In the preferred scheme of this application, this application adopt brushless motor unit with spool unit coaxial coupling for the whole structure of coiler is comparatively simple, and the nimble overall arrangement of being convenient for can make the spool unit obtain great moment of torsion simultaneously.

Drawings

FIG. 1 is a schematic view of the overall construction of a seatbelt retractor according to an embodiment of the present application;

FIG. 2 is a schematic exploded view of the core components of the seatbelt retractor according to an embodiment of the present application;

FIG. 3 is an exploded schematic view of a motor unit according to an embodiment of the present application;

FIG. 4 is a schematic view of a rotor structure according to an embodiment of the present disclosure;

FIG. 5 is a schematic view of a stator structure according to an embodiment of the present application;

FIG. 6 is a schematic view of a first connector according to an embodiment of the present disclosure;

FIG. 7 is a schematic view of a first bearing structure according to an embodiment of the present application;

FIG. 8 is a schematic view of a first carrier structure according to an embodiment of the present application;

FIG. 9 is a schematic view of a second carrier structure according to an embodiment of the present application;

FIG. 10 is a schematic view of a second bearing structure according to an embodiment of the present application;

FIG. 11 is a schematic diagram of a second carrier and second bearing assembly according to an embodiment of the present disclosure;

FIG. 12 is a schematic diagram of a second carrier, second bearing arrangement and planetary gear arrangement according to an embodiment of the present disclosure;

FIG. 13 is a schematic view illustrating an assembly of a first carrier and a first connector according to an embodiment of the present disclosure;

FIG. 14 is a schematic view of a central axis of an embodiment of the present application;

FIG. 15 is a schematic view of a pawl configuration of the ratchet-pawl mechanism of the present embodiment;

FIG. 16 is a schematic view of a pawl cage in a ratchet-pawl mechanism according to an embodiment of the present application;

FIG. 17 is a schematic illustration of the movement of the pawl to the ratchet outer ring gear without engagement in accordance with the embodiments of the present application;

FIG. 18 is a schematic illustration of the pawl engaging the outer ratchet ring gear in accordance with an embodiment of the present application;

FIG. 19 is a schematic view of a ratchet and force limiting lever configuration in accordance with an embodiment of the present application;

FIG. 20 is a schematic view of an assembled ratchet and force limiting lever according to an embodiment of the present application.

Reference numerals:

1: a motor unit (or brushless motor unit);

101: a first mechanical plate;

102: a rotor; 1021: polygonal holes; 1022: a first housing; 1022-1: a ring sidewall; 1022-2: a bottom wall; 1023: a permanent magnet;

103: a first connector; 1031: a first end; 1032: a second end; 1033: a middle cylindrical surface;

104: a first bearing:

105: a stator; 1051: a coil; 1052: an iron core ring;

106: a first carrier; 1061: a first bearing hole; 1062: a first bearing hole; 1063: a fixed shaft;

107: sun gear:

108: a planet wheel;

109: a planet wheel center shaft; 1091: the first end of the center shaft of the planet wheel; 1092: the second end of the center shaft of the planet wheel; 1093: the middle part of the center shaft of the planet wheel;

110: internal gear:

111: a second bearing;

112: a second bearing device; 1121: a protruding portion; 1122: a second bearing hole; 1123: a fixing hole; 1124: a second boss;

113: a motor housing;

114: a ratchet wheel; 1141: an outer gear ring outside the ratchet wheel; 1142: a ratchet wheel center hole;

115: a pawl; 1151: a first connecting hole on the pawl; 1152: a first boss on the pawl;

116: a pawl holder; 1161: a pair of arcuate guide holes in the pawl cage; 1162: a first runner on the pawl cage boss;

117: a clutch spring;

2: a control unit; 201: a third mounting hole;

3: a reel unit; 301: a force limiting rod;

4: a stand unit; 401: a first mounting hole; 402: a second mounting hole;

5: a locking unit;

6: a coil spring unit.

Detailed Description

For a better understanding of the objects, technical solutions and advantages of the embodiments of the present application, those skilled in the art will clearly and completely describe the technical solutions of the embodiments of the present application with reference to the drawings in the embodiments of the present application, and it is apparent that the described embodiments are some, but not all, embodiments of the present application.

It should be further noted that the terms "first," "second," and "second" in the description of the present application, the claims, and the above-described figures are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature.

In this application, unless specifically stated and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; either directly or indirectly, through intermediaries, or both, may be in communication with each other or in interaction with each other, unless expressly defined otherwise. The specific meaning of the terms in this application will be understood by those of ordinary skill in the art as the case may be. The present application is described below with reference to examples.

In the related art, the safety belt retractor is one of important components in a vehicle safety system, in the current vehicle safety system, the safety belt retractor has higher requirements, under the condition that a vehicle is about to collide, the safety belt webbing needs to be predicted in advance and is immediately tightened, and preparation is made for the vehicle about to collide, however, the current safety belt retractor adopts a direct current brush motor and a gunpowder pre-tightening device, so that the output torque of the safety belt retractor is smaller, and the requirements of people on the vehicle safety system cannot be better met. In view of this, the present application provides a seatbelt retractor including a motor unit, a reel unit, and a control unit; the motor unit is coaxially and directly connected with the reel unit, and the control unit controls the motor unit to rotate forwards or reversely at a required time point; the motor unit comprises a rotor and a speed reducing mechanism coaxially connected with the rotor through a first connecting piece; the output end of the speed reducing mechanism is coaxially connected with the first end of the force limiting rod of the reel unit through a ratchet pawl mechanism; when the motor unit rotates positively, the first end of the force limiting rod obtains the output of the speed reducing mechanism through the ratchet pawl mechanism, and the reel unit obtains the torque of forward rotation transmitted by the speed reducing mechanism through the force limiting rod, so that the pretension of the safety belt retractor is realized; when the motor unit rotates reversely, a ratchet and a pawl in the ratchet pawl mechanism are separated from contact, so that the force limiting rod does not rotate reversely.

In other words, the brushless motor unit is coaxially connected with the reel unit, so that the whole structure of the retractor is simple, the retractor is convenient to flexibly arrange, and meanwhile, the reel unit can obtain larger torque, and the requirements of people on a vehicle safety system can be further met.

While alternative implementations of embodiments of the present application are described below in conjunction with the accompanying drawings, it will be understood by those skilled in the art that the implementations described below are illustrative only and are not an exhaustive list, and that those skilled in the art may substitute, splice, or combine certain features or certain examples based on these implementations, which are still considered as the disclosure of the present application.

The overall structure of the seatbelt retractor according to the embodiment of the present application will be described in detail with reference to fig. 1 to 3.

As shown in fig. 1 to 3, the seatbelt retractor according to the embodiment of the present application is provided with a motor unit 1, a control unit 2, and a spool unit 3 through a fixing frame thereof. The control unit 2 directly connects the motor unit 1 and the reel unit 3 coaxially, and the control unit 2 controls the motor unit 1 to rotate forward or reverse at a required time point; the motor unit 1 includes a rotor 102, and a speed reduction mechanism coaxially connected with the rotor 102 through a first connection member 103; the output end of the speed reducing mechanism is coaxially connected with the first end of the force limiting rod 301 of the scroll unit 3 through a ratchet and pawl mechanism; when the motor unit 1 rotates positively, the first end of the force limiting rod 301 obtains the output of the speed reducing mechanism through the ratchet pawl mechanism, and the reel unit 1 obtains the torque of forward rotation transmitted by the speed reducing mechanism through the force limiting rod 301, so that the pretension of the safety belt retractor is realized; when the motor unit 1 is reversed, the ratchet 114 and the pawl 115 in the ratchet pawl mechanism are separated from contact, so that the force limiting rod 301 is not reversed.

The retractor structure provided in the embodiment of the present application is described above in its entirety, and the specific structure thereof is described below.

The motor unit 1 realizes forward rotation and reverse rotation under the control of the control unit 2, the control unit 2 judges that the vehicle is about to collide according to the information transmitted by sensors such as an automobile radar, and the motor unit 1 is provided with power for forward rotation so as to enable the motor unit 1 to rotate forward, and further tighten the webbing of the safety belt. Of course, the forward rotation of the motor unit 1 also requires the transmission of the rotational movement to the spool unit 3 via a reduction mechanism, the specific structure of which will be described later, to be able to tighten the webbing by the rotation of the spool unit 3.

As shown in fig. 2, the motor unit 1 is mounted at the left side of the overall frame of the retractor, the motor unit 1 is coaxially connected with the reel unit 3 through the control unit 2, and the mounting structure can directly transfer the torque output by the motor unit 1 to the reel unit 3, so that the loss of output torque is reduced, and the reel unit 3 can obtain larger torque.

The reel unit 3 passes through the bracket unit 4, that is, the reel unit 3 is clamped between the first mounting hole 401 and the second mounting hole 402 of the bracket unit 4, and one end of the reel unit 3 passes through the first mounting hole 401 and is coaxially connected with the motor unit 1 through the third mounting hole 201 of the control unit 2; the control unit 2 controls the motor unit 1 to rotate forward or backward at a required time point; the other end of the reel unit 3 is coaxially connected to the locking unit 5 through the second mounting hole 402, and at the same time, the other end of the locking unit 5 is coaxially connected to the coil spring unit 6.

As shown in fig. 2, the components of the overall structure of the retractor are sequentially connected from left to right in a coaxial connection manner, so that the overall structure of the retractor is simple, the coaxial connection can save space and is convenient for flexible layout, and the reel unit 3 can directly obtain larger torque from the motor unit 1.

As shown in fig. 3, the motor unit 1 is an exploded view of the motor unit 1, in this embodiment of the present application, the motor unit 1 is a brushless motor unit, and the brushless motor unit 1 has the characteristics of good speed regulation performance of a dc motor, and has the advantages of simple structure, no commutation spark, reliable operation and easy maintenance of an ac motor.

Specifically, fig. 3 is an exploded view of the brushless motor unit 1, where the brushless motor unit 1 includes several components, and includes, in order, a first mechanical plate 101, a rotor 102, a first connecting member 103, a first bearing 104, a stator 105, a first carrier 106, a sun gear 107, a planet gear 108, a planet gear center shaft 109, an inner gear 110, a second bearing 111, a second carrier 112, a motor housing 113, a ratchet 114, a pawl 115, a pawl holder 116, and a clutch spring 117 according to a transmission path thereof; wherein the first carrier 106 and the second carrier 112, and a planetary gear mechanism disposed therebetween cooperate to form a reduction mechanism; the sun gear 107, the planetary gear 108, and the internal gear 110 to which the sun gear 107 and the planetary gear 108 are attached cooperate to form the planetary gear mechanism; the ratchet 114, the pawl 115, the pawl holder 116, and the clutch spring 117 form the steering restriction mechanism by cooperating with each other.

The first mechanical board 101 is located at the forefront end of the brushless motor unit 1, and is connected with the motor housing 113 in a matching manner, so as to provide an accommodating space for components inside the brushless motor unit 1. The shape of the first mechanical plate 101 may be set according to the motor housing 113, in this embodiment, the shape of the first mechanical plate 101 is circular, and may be clamped on the motor housing 113.

Specifically, in the accommodating space formed by the first mechanical plate 101 and the motor housing 113, the rotor 102 is adjacent to the first mechanical plate 101, as shown in fig. 4, the rotor 102 includes a first housing 1022 and permanent magnets 1023, and the permanent magnets 1023 are annularly distributed inside the first housing 1022.

The rotor 102 may be divided into an outer rotor structure and an inner rotor structure, and the rotating body supported by the outer bearing is called an outer rotor structure, and the rotating body supported by the inner bearing is called an inner rotor structure; when the specific structure of the rotor is selected, the rotor can be further selected according to practical situations, and an outer rotor structure is adopted in the embodiment of the application.

As shown in fig. 4, the rotor 102 includes the first housing 1022 and the permanent magnet 1023, wherein the first housing 1022 includes a ring side wall 1022-1 and a bottom wall 1022-2, and the bottom wall 1022-2 and the ring side wall 1022-1 may be integrally formed. Specifically, the first housing 1022 may be made of metal and formed by CNC (Computer Numerical Control, numerically controlled milling machine), so that the bottom wall 1022-2 and the annular side wall 1022-1 are integrally formed, and the first housing 1022 made of metal has a more excellent heat dissipation effect and is easy to form. It is not excluded that the ring side wall 1022-1 and the bottom wall 1022-2 are provided as two parts for mating connection in practice.

A polygonal hole 1021 is formed in the center of the first housing 1022 of the rotor 102; specifically, the polygonal hole 1021 is provided on the bottom wall 1022-2 of the first housing 1022; the polygonal hole 1021 is for connecting with the first end 1031 of the first connector 103, so that the shape of the polygonal hole 1021 can be determined by the first end 1031 of the first connector, and in this embodiment, the polygonal hole 1021 is a regular hexagon hole.

As shown in fig. 4, the inner surface of the annular side wall 1022-1 is provided with the permanent magnet 1023, and specifically, the permanent magnet 1023 is annularly attached to the inner surface of the annular side wall 1022-1; wherein the space formed by the rotor first housing 1022 is for mounting the stator 105.

The brushless motor unit 1 is operated such that the entire rotor 102 rotates while the stator 105 in the middle is kept stationary.

As shown in fig. 5, the brushless motor unit 1 further includes a stator 105, a coil 1051 and an iron core ring 1052 are disposed on the stator 105, and the coil 1051 is annularly distributed on the iron core ring 1052; the stator 105 is coaxial with the rotor 102 and is positioned at the inner ring of the rotor 102; upon receiving the signal from the control unit 2, the brushless motor unit 1 drives the rotor 102 to rotate at a high speed with respect to the stator 105.

Specifically, the stator 105 is located at a space position formed by the rotor first housing 1022, that is, the rotor first housing 1022 encloses the stator 105, so in this embodiment, the stator 105 is an inner stator structure, but it is not excluded that the stator 105 is located outside the rotor.

As shown in fig. 5, the stator 105 has a cylindrical structure, and the innermost layer of the stator 105 has a cylindrical structure without upper and lower bottom surfaces, and the coils 1051 are annularly arranged around the outer surface of the stator 105, wherein the coils 1051 are arranged in pairs, and the coils 1051 are annularly arranged around the core ring 1052 outside the coils 1051, that is, the core ring 1052 is positioned at the outermost layer of the stator 105.

Specifically, the stator 105 is kept stationary throughout the process, the stator 105 generates a rotating magnetic field, the rotor 102 rotates at a high speed, and the rotor 102 is cut by magnetic lines of force in the rotating magnetic field to generate (output) current.

The rotor 102 outputs torque to the outside through the first connection member 103. As shown in fig. 6, the first connecting member 103 is schematically shown, a first end 1031 and a second end 1032 are provided on the first connecting member 103, and a middle cylindrical surface 1033 is provided between the first end 1031 and the second end 1032; the first end 1031 is connected to a polygonal hole 1021 in the first housing of the rotor; the middle cylindrical surface 1033 is sleeved with a first bearing 104, that is, the middle cylindrical surface 1033 of the first connecting piece is matched with the first bearing 104 to provide rotary support for the first connecting piece 103.

Specifically, the first end 1031 of the first connecting member is configured as a regular hexagon structure, and is connected with the polygonal hole 1021 on the bottom wall of the first housing of the rotor in a matching manner, that is, the first end 1031 of the first connecting member passes through the ring side wall of the rotor and is clamped on the polygonal hole 1021 on the bottom wall, where in the embodiment of the application, the structure of the first end 1031 of the first connecting member may also take other shapes, but it is required to ensure that the structure of the first end 1031 of the first connecting member and the polygonal hole 1021 on the first housing of the rotor can be connected in a matching manner.

In addition, as shown in fig. 7, the first bearing 104 is schematically configured, and the first bearing 104 is sleeved on the middle cylindrical surface 1033 of the first connecting member to provide rotary support.

Next, the reduction mechanism including the first carrier 106 and the second carrier 112, and the planetary gear mechanism provided therebetween will be described in detail.

As shown in fig. 8, the first bearing hole 1061 in the center of the first carrier 106 is configured to mount the first bearing 104, that is, the first bearing 104 on the middle cylindrical surface 1033 of the first connecting member and the first bearing hole 1061 in the center of the first carrier are cooperatively connected, and the rotor 102 transmits the output torque thereof to the outside through the first connecting member 103.

Meanwhile, a first bearing hole 1062 of the first carrier 106 is formed annularly around a surface of the first bearing hole 1061 in the center of the first carrier 106, and the first bearing hole 1062 is for connection with the central planet axle 109 in the planetary gear mechanism, which will be described in detail later.

Further, the first carrier 106 is provided with a fixing shaft 1063 protruding toward the second carrier 112, and the fixing shaft 1063 is inserted into the fixing hole 1123 of the second carrier 112 to integrate the first carrier 106 with the second carrier 112.

As shown in fig. 9, the second carrier 112 is centrally provided with a protruding portion 1121 facing the direction of the first carrier 106, the outer surface of the protruding portion 1121 is annularly provided with a second carrying hole 1122 and a fixing hole 1123 of the second carrier 112, the second carrying hole 1122 is connected with the central axis 109 of the planet wheel, the fixing hole 1123 is connected with a fixing shaft 1063 of the first carrier 106, and the first carrier 106 and the second carrier 112 can be combined into a whole through the fixing shaft 1063 and the fixing hole 1123. In this embodiment, the second bearing hole 1122 and the fixing hole 1123 are formed by annular insertion, or the second bearing hole 1122 and the fixing hole 1123 may be formed by annular insertion, that is, the second bearing hole 1122 may be formed by annular insertion on the outer surface of the second carrier protruding portion 1121, and the fixing hole 1123 may be formed by annular insertion on the outer ring or the inner ring.

Wherein the protruding part 1121 of the second carrier 112 is provided with a second bearing 111, and the second bearing 111 is further provided in a central hole provided in the motor housing 113, so that the second carrier 112 is rotatably supported.

As shown in fig. 10, the second bearing 111 is schematically configured, and the inner ring of the second bearing 111 is cooperatively connected with the protruding portion 1121 of the second carrier 112, and as shown in fig. 11, the second bearing 111 is mounted on the second carrier 112.

The first carrier 106 is integrally combined with the second carrier 112, and a planetary gear mechanism is installed in a space formed by the first carrier and the second carrier.

The planetary gear mechanism comprises a sun gear 107 and a planet gear 108, and an internal gear 110 for mounting the sun gear 107 and the planet gear 108; as shown in fig. 12, a plurality of planetary gears 108 meshed with the sun gear 107 are arranged on the periphery of the sun gear 107, and an inner gear 110 is arranged on the outer ring of the planetary gears 108; that is, the sun gear 107 is located at a central position, a plurality of planet gears 108 are annularly arranged on the periphery of the sun gear 107, the sun gear 107 is meshed with a plurality of the planet gears 108, and an inner gear 110 is arranged on the outer ring of the plurality of the planet gears 108 to be meshed with the inner gear.

Next, a connection manner of the planetary gear mechanism to the first carrier 106 and the second carrier 112 will be described in detail.

Specifically, as shown in fig. 13, the first end 1031 of the first connecting member 103 passes through the first bearing hole 1061 in the center of the first carrier 106 and then is connected with the polygonal hole 1021 on the first housing 1022 of the rotor in a matching manner; the first connector middle cylindrical surface 1033 carries the first bearing 104 thereon to fit into the first bearing hole 1061 of the first carrier 106, and the second end 1032 thereof is connected to the sun gear 107; i.e. the second end 1032 of the first connector is matingly coupled to the inner flange of the sun gear 107.

Meanwhile, a plurality of planet gears 108 are disposed on the periphery of the sun gear 107, the planet gears 108 are mounted between the first carrier 106 and the second carrier 112 through the planet gear center shaft 109, as shown in fig. 14, the planet gear center shaft 109 is formed by three sections of cylinders with different diameters, the outermost two ends of the planet gear center shaft 109 are respectively connected with the first carrying hole 1061 of the first carrier 106 and the second carrying hole 1122 of the second carrier 112, the middle portion 1093 is inserted into the inner ring of the planet gears 108 (as shown in fig. 12), that is, the first end 1091 of the planet gear center shaft 109 passes through the inner ring of the planet gears 108 to be connected with the first carrying hole 1061 of the first carrier 106, the middle portion 1093 is located in the inner ring of the planet gear 108, and the second end of the planet gear center shaft 109 is connected with the second carrying hole 1122 of the second carrier 112, at this time, the planet gear mechanism connects the first carrier 106 and the second carrier 112.

When the rotor 102 rotates at a high speed, the first connecting piece 103 connected with the rotor is driven to rotate, the first connecting piece 103 rotates to drive the sun wheel 107 connected with the first connecting piece to rotate, the sun wheel 107 rotates to drive the planetary wheels 107 meshed with the sun wheel to rotate, and the planetary wheels 107 rotate to further drive the first carrier 106 and the second carrier 112 to rotate.

The structure of the second carrier 112 for connecting to the ratchet pawl mechanism is, as shown in fig. 9, a pair of bosses are oppositely disposed at the outer edge of the outer side end surface of the second carrier 112, and the bosses are connected to the pawls 115, specifically, as shown in fig. 15, a first connecting hole 1151 is disposed on the pawls 115, and a pair of second bosses 1124 on the second carrier 112 are inserted into the first connecting holes 1151 of the pawls to be cooperatively connected, and it should be noted that each pawl 115 is provided with a first connecting hole 1151, a plurality of second bosses 1124 on the second carrier 112 may be disposed, and the second bosses 1124 on the second carrier 112 are matched with the first connecting holes 1151 on the pawls 115.

At high speeds of rotation of the rotor 106, the second carrier 112 rotates the pair of pawls 115 coupled thereto after the series of rotations described above.

Wherein, the output end of the speed reducing mechanism is coaxially connected with the first end of the force limiting rod 301 of the scroll unit 3 through a ratchet and pawl mechanism.

When the brushless motor unit 1 rotates positively, the first end of the force limiting rod 301 obtains the output of the speed reducing mechanism through the ratchet and pawl mechanism, and the reel unit 3 obtains the torque of forward rotation transmitted by the speed reducing mechanism through the force limiting rod 301, so that the pretension of the safety belt retractor is realized; when the brushless motor unit 1 is reversed, the ratchet 114 and the pawl 115 in the ratchet pawl mechanism are out of contact, so that the force limiting rod 301 is not reversed.

Specifically, the steering limiting mechanism mainly comprises the ratchet pawl mechanism, the moment of ratchet rotation is realized through the matching relationship, the pawl 115 is matched with the ratchet 114, and the pawl 115 is separated from the ratchet 114 when the moment of ratchet 114 rotation is not required. The central hole 1142 of the ratchet 114 is used as an output end of the speed reducing mechanism, and is coaxially connected to the first end of the force limiting rod 301. The rotation of the ratchet 114 can drive the force limiting rod 301 to rotate and further drive the reel unit to rotate through the rotation of the force limiting rod 301, so that the webbing belt is wound up; the following focuses on the construction and operation of the steering limiting mechanism.

As mentioned above, the second carrier 112 is provided with a pair of second bosses 1124 disposed opposite to each other at a position near the outer edge, the pawl 115 of the ratchet-pawl mechanism is provided with a first connecting hole 1151, and the second bosses 1124 of the second carrier are inserted into the first connecting holes 1151 of the pawl to be cooperatively connected.

Meanwhile, as shown in fig. 16 and 17, the pawl holder 116 is provided with a pair of arc-shaped guide holes 1161 extending from the outer edge toward the inner diameter direction in opposition near the outer edge, and two pawls 115 are respectively mounted in the arc-shaped guide holes 1161 by sliding along the arc-shaped guide holes 1161 by first bosses 1152 provided on the surfaces thereof. Because the arc-shaped guide hole 1161 extends in a curved manner from the outer edge of the pawl holder 116 to the inner diameter direction, when the pawl 115 is positioned at one end of the arc-shaped guide hole 1161 near the inner diameter, the pawl 115 is closer to the ratchet 114 coaxially installed with the pawl holder 116, so that the pawl 115 and the ratchet 114 can be matched; conversely, if the pawl 115 is located at the end of the arcuate guide hole 1161 near the outer edge, it will be out of contact with the ratchet 114.

The ratchet wheel 115 is coaxially arranged on the surface of the pawl holder 116, which is close to the upstream side of the transmission chain; the ratchet 115 obtains axial positioning through cooperation with the force limiting rod 301; a central boss is arranged on one surface of the pawl retainer 116, which is close to the downstream of the transmission chain, and a first sliding groove 1162 is arranged on the central boss; a ' n ' -shaped ' clutch spring is clamped on the pawl holder 116 through a first sliding groove 1162, and a positioning boss arranged on the pawl holder 116 is sleeved in the middle of the head part of the clutch spring and can be blocked by the positioning boss; when the brushless motor 1 starts to rotate in the forward direction due to the friction force generated by the clutch spring 117, the pawl holder 116 is blocked from rotating or rotating slowly therewith, and in the process, the pawl 115 slides to the end position of the arc-shaped guide hole 1161 near the inner diameter.

With the above structure, steering restriction can be achieved, and the principle thereof will be described below with reference to a specific course of movement. When the brushless motor unit 1 starts to rotate in the forward direction, the rotor 102 drives the second carrier 112 to rotate, and since the pawl holder 116 is connected to the second carrier 112 through the two pawls 115, the second carrier 112 drives the pawls 115 to rotate, and the pawls 115 first slide from a position near the outer edge surface to a position near the end of the inner edge surface of the arcuate guide hole 1161 under the guidance of the arcuate guide hole 1161, and engage with the outer gear ring 1141 of the ratchet 114 at this position.

Wherein the clutch spring 117 engages the pawl holder 116 through the first sliding groove 1162, and when the brushless motor unit 1 starts to rotate in the forward direction due to the friction force generated by the clutch spring 117, the ratchet holder 116 is blocked from rotating or rotating slowly therewith, and in the process, the pawl 115 slides to the end position of the arc-shaped guide hole 1161 near the inner diameter, as shown in fig. 18. The pawl 115 is now in engagement with the ratchet 114.

After the pawl 115 is engaged with the ratchet 114, the rotation of the second carrier 112 will continue to rotate the pawl 115 in the ratchet-pawl mechanism, and since the pawl 115 has slid to the end position of the arcuate guide hole 1161, the rotation of the pawl 115 will rotate the ratchet holder 116 against the friction provided by the clutch spring 117; and, at this time, the ratchet 114 has engaged with the pawl 115, so that the ratchet 114 rotates accordingly. As described above, the rotation of the ratchet 114 further rotates the force limiting rod 301 engaged with the central hole 1142, and further rotates the spool unit 3, so as to wind up the webbing.

In contrast to the forward rotation of the above brushless motor unit 1, the pawl 115 slides from its position near the inner diameter to the position near the start end of the arc-shaped guide hole 1161 on the outer peripheral surface under the guide of the arc-shaped guide hole 1161 and is disengaged from the ratchet outer ring 1141 by the reverse rotation of the brushless motor unit 1. Thus, when the brushless motor unit 1 is reversed, the ratchet 114 cannot be driven to rotate, so that steering limitation is realized, that is, the reel unit 3 can be driven to rotate only when the brushless motor unit 1 rotates in the forward direction; the brushless motor unit 1 rotates reversely, and the reel unit 3 cannot be driven to rotate.

The connection between the ratchet 114 and the force limiting lever 301 is further described below.

The ratchet 114 has a center hole 1142 as an output end of the speed reducing mechanism, and the first end of the force limiting lever 301 of the spool unit 3 is connected through the center hole 1142.

As shown in fig. 19, the first end of the force limiting rod 301 is provided with a polygonal groove or a spline groove, and may be directly inserted into the ratchet central hole 1142 or the spline hole, at this time, the force limiting rod 301 and the ratchet 114 are connected, the ratchet 114 rotates to drive the force limiting rod 301 to rotate, in the actual process, the polygonal groove or the spline groove of the force limiting rod 301 may be selected according to the actual requirement, or may be in another form of groove structure, but it should be noted that the groove provided on the force limiting rod 301 is matched with the hole of the ratchet 114.

As shown in fig. 20, the polygonal groove at the first end of the force limiting lever 301 is inserted into the ratchet wheel center hole 1142, wherein the pair of pawls 115 are engaged at the outer gear ring 1141 of the ratchet wheel 114.

When the force applied to the safety belt reaches a certain degree during severe collision of the vehicle, the force limiting rod 301 rotates to enable the safety belt to release some webbing out, so that the pressure of the safety belt on the chest of the passenger is relieved.

As described above, when the brushless motor unit 1 rotates in the forward direction, the rotor 102 is driven to rotate, the rotor 102 drives the speed reduction mechanism on the first connector 103 to rotate, and the rotation output reduced to a suitable rotation speed is transmitted to the steering limiting mechanism after the rotation of the speed reduction mechanism, and the steering through the steering limiting mechanism is transmitted to the force limiting rod 301 of the reel unit 3. The force limiting rod 301 obtains the torque of the forward rotation transmitted by the speed reducing mechanism, so that the pretensioner of the retractor is realized. When the brushless motor unit 1 starts to rotate in the reverse direction, the steering restriction mechanism cannot bring the steering restriction mechanism to the rotation of the force restriction lever 301, and the webbing can be returned to a freely stretchable state by releasing the ratchet 114 from contact with the pawl 115 due to the reverse rotation, whereby the unidirectional driving of the spool unit 3 is achieved.

As described above, the seatbelt retractor according to the embodiment of the present application has the brushless motor unit 1, the control unit 2, and the spool unit 3, wherein the brushless motor unit 1 and the spool unit 3 are coaxially and directly connected, and the control unit 2 controls the brushless motor unit 1 to rotate forward or reverse at a desired time point; the brushless motor unit 1 includes a rotor 102, and a speed reduction mechanism coaxially connected to the rotor 102 via a first connection member 103; the output end of the speed reducing mechanism is coaxially connected with the first end of the force limiting rod 301 of the scroll unit 3 through a ratchet and pawl mechanism; when the brushless motor unit 1 rotates positively, the first end of the force limiting rod 301 obtains the output of the speed reducing mechanism through the ratchet and pawl mechanism, and the reel unit 3 obtains the torque of forward rotation transmitted by the speed reducing mechanism through the force limiting rod 301, so that the pretension of the safety belt retractor is realized; when the brushless motor unit 1 is reversed, the ratchet 114 and the pawl 115 in the ratchet pawl mechanism are out of contact, so that the force limiting rod 301 is not reversed. Due to the adoption of the technical scheme that the brushless motor unit and the reel unit are coaxially and directly connected, the whole safety belt retractor is smaller in size, and a more proper installation position can be obtained.

Another embodiment of the present application is a seatbelt including the above-described seatbelt retractor.

While the invention has been described with reference to the preferred embodiments, the scope of the invention is not limited thereto, and any person skilled in the art can make possible variations and modifications without departing from the spirit and scope of the invention. The scope of protection of the present application should therefore be determined by the claims of the present application.

Claims (10)

1. A seatbelt retractor, characterized by comprising: a motor unit, a reel unit, and a control unit;

the motor unit is coaxially and directly connected with the reel unit, and the control unit controls the motor unit to rotate forwards or reversely at a required time point;

the motor unit comprises a rotor and a speed reducing mechanism coaxially connected with the rotor through a first connecting piece; the output end of the speed reducing mechanism is coaxially connected with the first end of the force limiting rod of the reel unit through a ratchet pawl mechanism;

when the motor unit rotates positively, the first end of the force limiting rod obtains the output of the speed reducing mechanism through the ratchet pawl mechanism, and the reel unit obtains the torque of forward rotation transmitted by the speed reducing mechanism through the force limiting rod, so that the pretension of the safety belt retractor is realized; when the motor unit rotates reversely, a ratchet and a pawl in the ratchet pawl mechanism are separated from contact, so that the force limiting rod does not rotate reversely.

2. The seatbelt retractor according to claim 1, wherein the motor unit is a brushless motor unit, and the brushless motor unit includes a stator;

the stator is provided with coils and iron core rings, and the coils are annularly distributed on the iron core rings; the stator is coaxial with the rotor and is positioned at the inner ring of the rotor; and the brushless motor unit drives the rotor to rotate at a high speed relative to the stator after receiving the signal of the control unit.

3. The seatbelt retractor according to any one of claims 1-2, wherein the reduction mechanism includes a first carrier and a second carrier, and a planetary gear mechanism provided therebetween;

the planetary gear mechanism comprises a sun gear and a planetary gear, and an inner gear is provided with the sun gear and the planetary gear; the first end of the first connecting piece is connected with the rotor of the motor unit, and the second end of the first connecting piece is connected with the sun gear after passing through the first bearing hole in the center of the first carrier; the periphery of the sun gear is provided with a plurality of planet gears meshed with the sun gear; an inner gear is arranged on the outer ring of the planet wheel;

the center shaft of the planet wheel is provided with a first bearing hole with two ends respectively connected with the first bearing device and a second bearing hole of the second bearing device;

And the end face of the second carrier, which faces the outer side, is provided with a structure for connecting the ratchet and pawl mechanism.

4. A seatbelt retractor according to claim 3, wherein a fixing shaft protruding toward the second carrier is provided on the first carrier, and the fixing shaft is inserted into a fixing hole on the second carrier so that the first carrier is integrated with the second carrier.

5. A seatbelt retractor according to claim 3, wherein the first bearing hole in the centre of the first carrier is fitted with a first bearing, and the cylindrical surface in the middle of the first connector cooperates with the first bearing to provide rotational support.

6. A seatbelt retractor according to claim 3, wherein the second carrier is centrally provided with a projection directed towards the first carrier, the projection being provided with a second bearing which cooperates with a central aperture provided in the motor housing such that the second carrier is rotatably supported.

7. A seatbelt retractor according to claim 3, wherein the second carrier is provided with a structure for connecting the ratchet-pawl mechanism on an outer side end face thereof, the ratchet-pawl mechanism includes a pawl holder, the pawl is mounted to the pawl holder, the motor unit starts to rotate in a forward direction, and the process of bringing the pawl of the ratchet-pawl mechanism into engagement with the outer gear ring of the ratchet is achieved by:

A pair of arc-shaped guide holes extending from the outer edge to the inner diameter direction are oppositely arranged at the position close to the outer edge of the pawl retainer, and two pawls are respectively arranged in the arc-shaped guide holes through first bosses arranged on the surfaces of the pawls; the pawl is provided with a first connecting hole, and a boss on the upper-stage transmission piece is inserted into the first connecting hole;

the motor unit starts to rotate positively, and the pawl firstly slides from the position close to the outer edge surface to the end position close to the inner diameter of the arc-shaped guide hole under the guidance of the arc-shaped guide hole, and is meshed with the ratchet wheel outer gear ring at the end position.

8. The seatbelt retractor according to claim 7, wherein the pawl holder is provided with a central boss on which a first chute is provided; the clutch spring in a shape like a Chinese character 'ji' is clamped with the pawl retainer through the first chute, and the middle of the head part of the clutch spring is sleeved with a positioning boss arranged on the retainer and can be blocked by the positioning boss; when the motor unit starts to rotate forward due to friction force generated by the clutch spring, the pawl holder is blocked from rotating or rotating slowly, and in the process, the pawl slides to the tail end position of the arc-shaped guide hole close to the inner diameter.

9. The seatbelt retractor according to claim 8, wherein the motor unit starts to rotate reversely, and a pawl of the ratchet pawl mechanism is brought out of engagement with an outer gear ring of the ratchet.

10. A seat belt comprising a seat belt retractor according to any one of claims 1 to 9.

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