KR20200075266A - Retractor for seat belt - Google Patents

Abstract

The present invention relates to a retractor for a seat belt, which stops pulling out a webbing by a control signal and keeps the webbing stopped even when there is no control signal after the webbing is stopped. According to the present invention, the retractor for a seat belt comprises: a frame; a spool which is rotatably inserted and mounted in the frame such that the webbing is wound on or unwound from the spool; a wheel gear which is placed on one side of the frame to rotate by the rotation of the spool and has a plurality of one-directional sawteeth on an outer circumferential surface thereof; a locking unit including a lock release unit which performs the lock releasing motion in the direction of pulling out and letting in the webbing, a lock keeping unit which comes in contact with the one-directional sawteeth to lock the webbing in the direction of pulling out the webbing, and an operation unit which converts between the locking motion and the lock releasing motion in the direction of pulling out the webbing in accordance with a control signal; and a cover plate which accommodates the locking unit, covers the wheel gear, and is fixed on one side of the frame.

Description

RETRACTOR FOR SEAT BELT

The present invention relates to a retractor for a seat belt, and more particularly, to a retractor for a seat belt that stops the withdrawal of the webbing by the control signal and maintains the withdrawal interruption state even in the absence of the control signal after the withdrawal of the webbing is stopped.

When a person rides on a vehicle or device, various safety devices are provided to prevent the person on board from leaving the vehicle or device due to collision between vehicles or other objects.

A representative one of them is a seat belt, which uses the seat belt to stably fix the lower abdomen and chest of a person riding on the vehicle or device to the seat. However, it is often the case that the degree of collision between vehicles or other objects increases beyond a standard, and the seat belt may not function properly, and in such a case, the safety of the person riding the vehicle or device is compromised.

Accordingly, various technologies have been developed so that the seat belt can function properly even when the degree of collision between vehicles or other objects is large. Among them, a technology that is currently in the spotlight is a retractor, and the retractor may have various functions such as an automatic locking retractor function, a block out function, and an emergency locking retractor function.

The automatic locking retractor function means that when a user withdraws the webbing for a predetermined length, such as a method for mounting and restraining a child seat on a seat of a vehicle or a device, the webbing is no longer withdrawn and can only be pulled in. It is a function to enable.

However, a conventional retractor (Republic of Korea Patent Registration No. 10-0801603) having such an automatic locking retractor function adopts a rotating structure and the like, so that the number of parts of the retractor is greatly increased and its structure is very complicated. It is natural that the manufacturing cost will increase due to the increase in the number of processes for manufacturing. Also, as the number of parts increases, interference between each part, friction, and noise will also be involved.

Republic of Korea Patent Registration No. 10-0801603 "Rotating structure of seat belt retractor"

The present invention stops the withdrawal of the webbing by the control signal and the seatbelt employing an electric power device such as a solenoid to implement an automatic locking retractor function to maintain the withdrawal interruption state even in the absence of the control signal after the withdrawal of the webbing is stopped. It is an object to provide a retractor.

The present inventor seat belt retractor is rotatably inserted into the frame, a spool in which the webbing is wound or unwound, provided on one side of the frame, rotated together according to the rotation of the spool, and a wheel formed with a plurality of unidirectional teeth on the outer circumferential surface A gear, a unlocking unit for unlocking the webbing with respect to the withdrawal direction and a withdrawal direction, a locking retainer for contacting a unidirectional tooth to perform a locking operation for the webbing withdrawal direction, and withdrawal of the webbing according to a control signal It has a locking unit composed of an operation unit that performs a conversion between a locking state and a unlocking state for a direction, and a cover plate that accommodates the locking unit and is fixed to one side of the frame while covering the wheel gear.

In addition, the operation unit is composed of a plunger and a winding unit for advancing and reversing the plunger according to a control signal. , It is composed of a holding portion that prevents the movement of the plunger during the locking operation, it is preferable that the unlocking portion is such that the locking portion is spaced apart from the one-way teeth.

In addition, the locking retainer has a movement transmission unit for performing a rotational movement according to the forward or backward movement of the plunger, the rotational axis and the rotational direction of the locking portion are the same as the rotational axis and rotational direction of the movement transmission portion, respectively, and the locking portion in the locked state It is preferable to be able to rotate within a predetermined rotational angle in the direction of inlet of the webbing, which is the direction opposite to the direction of rotation, so that locking in the inlet direction of the wheel gear is released.

In addition, the locking portion is provided with a rotation limiting portion, the movement transmitting portion has first and second locking portions formed spaced apart by a separation space, and the rotation limiting portion is located in the separation space between the first and second locking portions, and the movement transmitting portion It is preferable that the rotational motion is transmitted to the locking portion through the rotation limiting portion contacting the first or second locking portion, and the width of the separation space is preferably larger than the width of the rotation restriction portion located in the separation space.

In addition, it is preferable that a return spring is provided to connect each of the engaging portion and the driving transmission portion.

The present invention can maintain a locked state without supply of a continuous control signal (for example, current), thereby solving the heat generation problem when implementing the retractor function, and thereby solve problems such as overload due to heat generation, shortening of the solenoid life, and reduced adsorption power. It has the effect of solving.

In addition, the present invention has an effect of allowing the clutch function to be implemented in the locked state in the retractor for seat belts so that the locking is maintained for webbing drawout and unlocking for webbing intake.

1 is an exploded perspective view of a first embodiment of a retractor for a seat belt according to the present invention.
2A and 2B are partial operational views of the retractor for the seat belt of FIG. 1.
3 is an exploded perspective view of a second embodiment of a retractor for seat belts according to the present invention.
4A and 4B are partial operational views of the retractor for the seat belt of FIG. 1.
5A and 5B are bottom views of the locking unit after the seat belt retractor of FIG. 3 is assembled.

Hereinafter, the present invention will be described in detail through examples and drawings. However, this is not intended to limit the present invention to specific embodiments, and should be understood as including various modifications, equivalents, and/or alternatives of embodiments of the present invention. In connection with the description of the drawings, similar reference numerals may be used for similar elements.

In this document, expressions such as "have", "can have", "includes", or "can contain" are the presence of the corresponding feature (eg, a component such as a numerical value, function, operation, or part). And does not exclude the presence of additional features.

In this document, expressions such as “at least one of A or B”, “at least one of A or/and B”, or “one or more of A or/and B” may include all possible combinations of the items listed together. . For example, “A or B”, “at least one of A and B”, or “at least one of A or B” includes (1) at least one A, (2) at least one B, Or (3) all cases including both at least one A and at least one B.

As used herein, expressions such as "first", "second", "first", or "second" can modify various components, regardless of order and/or importance, and can change one component to another It is used to distinguish from the components, but does not limit the components. For example, the first user device and the second user device may indicate different user devices regardless of order or importance. For example, the first component may be referred to as a second component without departing from the scope of rights described in this document, and similarly, the second component may be referred to as a first component.

Some component (eg, first component) is "(functionally or communicatively) coupled with/to" another component (eg, second component) or " When referred to as "connected to", it should be understood that any of the above components may be directly connected to the other component, or may be connected through another component (eg, a third component). On the other hand, when a component (eg, the first component) is said to be “directly connected” or “directly connected” to another component (eg, the second component), the component is not It can be understood that other components (eg, the third component) do not exist between the other components.

As used herein, the expression "configured to" is, depending on the context, for example, "having the capacity to", "suitable for" It can be used interchangeably with ", "designed to", "adapted to", "made to", or "capable of". The term "configured (or set) to" may not necessarily mean "specifically designed to" in hardware. Instead, in some situations, the expression "device configured to" may mean that the device "can" with other devices or parts. For example, the phrase “processor configured (or set) to perform A, B, and C” executes a dedicated processor (eg, embedded processor) to perform the operation, or one or more software programs stored in the memory device. By doing so, it may mean a general-purpose processor (eg, a CPU or application processor) capable of performing the corresponding operations.

The terms used in this document are only used to describe specific embodiments, and may not be intended to limit the scope of other embodiments. Singular expressions may include plural expressions unless the context clearly indicates otherwise. Terms used herein, including technical or scientific terms, may have the same meaning as commonly understood by a person skilled in the art described in this document. Among the terms used in this document, the terms defined in the general dictionary may be interpreted as having the same or similar meaning in the context of the related art, and in an ideal or excessively formal meaning, unless explicitly defined in this document. Is not interpreted. In some cases, even terms defined in this document cannot be interpreted to exclude embodiments of the document.

1 is an exploded perspective view of a first embodiment of a retractor for a seat belt according to the present invention. 2A and 2B are partial operational views of the retractor for the seat belt of FIG. 1.

The seat belt retractor (1) is rotatably inserted into the frame (2) and the frame (2) and is connected to the center of the spool (3) and the spool (3) to which the webbing (not shown) is wound or unwound. The spool (3) is provided on one side of the frame (2), the webbing guide (7) formed on the frame (2), the pole (5) protruding outward of the spool (3), and the pole (5). It is rotated together according to the rotation of the wheel gear 9 is formed with a plurality of unidirectional teeth (9a) on the entire outer circumferential surface, and receives a locking unit operated by a control signal, while covering the wheel gear 9, the frame (2) It includes a cover plate 11 fixed to one side of, and a locking unit cover 13 fixed to one side of the cover plate 11 while covering the locking unit. However, the frame (2), the spool (3), the pole (5), the webbing guide (7) and the wheel gear (9) are only technologies that are naturally recognized by those skilled in the art to which the present invention pertains. , Detailed description is omitted. In this embodiment, the locking unit is composed of a power unit 20, a motion conversion unit 30, a return spring 40 and a connecting pin 50.

The cover plate 11 includes a first accommodating part S1 into which the power part 20 is inserted and a second accommodating part S2 in communication with the first accommodating part S1 and into which the motion converting part 30 is inserted and received. ) And a penetrating portion P communicating between the second receiving portion S2 and the wheel gear 9.

The power unit 20 is to perform conversion or switching between the locked state and the unlocked state (or initial state), the case 21 on which one side is opened and the receiving space S3 is formed, and once in the receiving space S3 This insertion is accommodated and the other end extends to the outside of the open side of the case 21 and is a magnetic chain plunger 22 installed to be able to move forward/backward in a linear direction, and a through hole 24 formed at the other end of the plunger 22 To be equipped. The other end of the plunger 22 is divided into two. In order to maintain the state in which the plunger 22 has been moved to the reverse direction of the receiving space S3 (locking state-withdrawal interrupted state), the holding portion 25 in the receiving space S3 is close to the open one side of the case 21 ) Is provided. Also, in the accommodation space S3, a winding portion 26 (for example, a solenoid coil) that forms a magnetic field according to a control signal (electrical signal) to advance/reverse the plunger 22 is provided. Preferably, the holding portion 25 is made of, for example, a material such as a magnet, and the holding portion 25 prevents the movement of the plunger 22 by continuously pulling the plunger 22 with magnetic force (manpower).

In order to prevent the position change of the power unit 20 between the first receiving portion S1 and the second receiving portion S2, the first and second protruding portions 11a and 11b spaced apart from each other by the second receiving portion It is formed to extend from the side wall of (S2) to the center. The spacing between the first and second protrusions 11a and 11b should be at least larger than the diameter of the plunger 22 to enable the forward/reverse of the plunger 22 of the power unit 20.

The motion converting part 30 converts the linear motion of the plunger 22 into a rotational motion, and is connected to the first shaft part 30a protruding outwardly and the central axis of the first shaft part 30a, and is first A first extension portion 31 extending outward from the central axis of the shaft portion 30a, and a second shaft portion 34 whose central axis is parallel to the central axis of the first shaft portion 30a and is hollow inside; It is composed of a second extension portion 36 which is vertically connected to the central axis of the second shaft portion 34 and extends outside the central axis of the second shaft portion 34.

The first extension portion 31 includes a rectangular insertion hole 32 composed of a long axis and a short axis, and a support portion 33 for supporting the second end 43 of the return spring 40 on one side.

The second extension portion 36 has a round shape in the middle thereof, and may be caught in one-way teeth 9a and has a locking portion 35 extending outwardly of the second extension portion 36.

A fixed shaft 14 protruding outward from the second accommodating portion S2 is inserted into the hollow in the second shaft portion 34, and the first and second shaft portions 30a, 34 and the fixed shaft 14 are rotated. In this way, the motion converter 30 is rotatably installed.

In addition, in order to reduce the variability when the motion conversion unit 30 rotates, the locking unit cover 13 is a case 13a that covers the first and second receiving parts S1, S2, and the penetrating part P And, the upper portion of the first shaft portion (30a) is provided with an insertion hole (13b) is rotatably inserted. The central axis of the fixed shaft 14, the first and second shaft portions 30a, 34, and the insertion hole 13b forms the same rotational axis, so that the motion converting portion 30 performs linear motion of the power unit 20 (forward/ Reverse).

In addition, the engaging portion 35 formed in the second extension portion 36 is located near the one-way teeth 9a of the wheel gear 9 through the through portion P, and is rotated by the rotation of the motion converting portion 30 It is in contact with the one-way teeth (9a) to prevent the rotation of the wheel gear (9) or spaced apart from the one-way teeth (9a) so that the bent gear (9) can be rotated.

The return spring 40 has a plurality of wires forming a hollow, and the wound part 41 is wound, and the first end 42 and the second end of the wire material having a predetermined angle and extending outward of the winding part 41. It consists of (43). The first shaft portion 30a is inserted into the hollow portion of the winding portion 41, the second end portion 43 is located at the support portion 33, and the first end portion 41 has a predetermined distance to the cover plate 11 While being inserted and fixed between the formed third and fourth protrusions 12a, 12b.

The connecting pin 50 is mounted on one side of the pin head 51 and the pin head 51 having a diameter larger than the short axis diameter of the insertion hole 32, and is smaller than the diameter of the pin head 51 and of the insertion hole 32. A first fixed shaft 52 having a diameter that can be moved in the long axis direction and inserted into the insertion hole 32, a second having a diameter smaller than the diameter of the first fixed shaft 52, and inserted and fixed into the through hole 24 It consists of a fixed shaft (53).

A part of the plunger 22 protruding out of the case 21 is located between the first and second extensions 31 and 36, and the connecting pin 50 is inserted through the insertion hole 32 and is 2 The fixed shaft 53 is inserted and fixed in the through-hole 24, thereby connecting the power unit 20 and the motion conversion unit 30 to transmit power.

A control unit (not shown) for applying a control signal (locking signal, unlocking signal) to the seat belt retractor is provided, and the control unit generates a control signal according to the driving state of the vehicle, the withdrawal state of the webbing, etc. (20).

Next, the operating state of the retractor for seat belts according to the first embodiment is described. First, the initial state (unlocked state) of the retractor for seat belts is described. As shown in FIG. 2A, the control unit does not need to apply a control signal to the power unit 20, and the plunger 22 is advanced to the outside of the case 21 by the restoring force (tension) of the return spring 40. By protruding as much as possible, the state in which the engaging portion 35 is separated from the one-way teeth 9a is maintained by the forward state of the plunger 22 or the forward motion. Even if the holding portion 25 is pulling the plunger 22, the unlocking state is maintained because the restoring force of the return spring 40 is greater than the attraction force of the holding portion 25.

Next, when locking is required for the wheel gear 9, the control unit applies a locking signal to the power unit 20, a magnetic field is formed in the winding 26 of the power unit 20, and a magnetic force caused by the magnetic field By this, the plunger 22 moves into the case 21 (accommodating space S3), that is, the plunger 22 moves backward, and the backward movement of the plunger 22 rotates by the motion converter 30 Is converted into movement. Since the magnetic force formed in the power unit 20 is greater than the restoring force of the return spring 40 (or the combined force of the restoring force of the return spring 40 and the attraction force of the holding unit 25), the motion converting unit 30 has a plunger 22 By rotating by an angle corresponding to the moving distance of ), the engaging portion 35 contacts the one-way teeth 9a to stop the rotation of the wheel gear 9. That is, the withdrawal of the webbing is stopped by the stoppage of rotation of the wheel gear 9. With respect to the rotation angle of the motion converting section 30, the distance in the long axis of the insertion section 32 is equal to or greater than the movable distance (direction travel distance) of the plunger 22.

Next, the control unit stops the application of the locking signal in a state in which the webbing is withdrawn due to the locking state. That is, the magnetic force due to the magnetic field formed in the winding portion 26 is extinguished, but the holding portion 25 is pulling the plunger 22. Since the attraction force of the holding part 25 becomes larger than the restoring force of the return spring 40, the locking state can be maintained as it is.

Next, the control unit applies a unlocking signal to the power unit 20 to release the locked state. The plunger 22 moves in the forward direction by the magnetic force generated by the magnetic field formed in the winding part 26 of the power unit 20, and the motion converting unit 30 rotates by the linear movement of the plunger 22. The part 35 is spaced apart from the one-way teeth 9a to release the locking state. That is, since the magnetic force formed in the power unit 20 and the restoring force of the return spring 40 are greater than the attraction force of the holding unit 25, the motion conversion unit 30 rotates by an angle corresponding to the moving distance of the plunger 22 can do.

As described above, the withdrawal of the webbing is stopped by the locking operation, and the withdrawal interruption state is maintained even in the absence of the control signal (locking signal) after the withdrawal of the webbing is stopped. When the strength of the attraction force of the holding portion 25, the restoring force of the return spring 40 and the magnetic force of the power portion 20 in the above-described process are compared, the weight of the motion converting portion 30, the weight of the plunger 22 The like should also be considered, but these points are only recognized to those of ordinary skill in the art to which the present invention pertains, and the description thereof is omitted.

3 is an exploded perspective view of a second embodiment of a retractor for a seat belt according to the present invention, and FIGS. 4A and 4B are partial operational views of the retractor for a seat belt of FIG. 1. The seat belt retractor according to the second embodiment includes a frame 2, a spool 3, a pole 5, a webbing guide 7 and a wheel gear 9 in the retractor for a seat belt according to the first embodiment ), and only those components having the same configuration and differences in configuration are described.

The cover plate 11-1 accommodates a locking unit operated by a control signal, and is fixed to one side of the frame 2 while covering the wheel gear 9, and the locking unit cover 13-1 covers the locking unit. It is fixed to one side of the cover plate 11-1 while covering. The locking unit in the second embodiment includes a power unit 20, a first return spring 40-1, a connecting pin 50, a motion transmitting unit 60, a locking unit 70, and a second return spring ( 80) and the like.

The cover plate 11-1 includes a first accommodating part S1 into which the power part 20 is inserted and a fourth accommodating part communicating with the first accommodating part S1 and into which the motion transmitting part 60 is inserted and received. (S4) and a through portion (P-1) communicating between the fourth receiving portion (S4) and the wheel gear (9). The structure of the power unit 20 in the second embodiment is the same as the structure of the power unit 20 in the first embodiment.

In order to prevent the position change of the power unit 20 between the first accommodating part S1 and the fourth accommodating part S4, the first and second protruding parts 11a, 11b spaced apart at regular intervals are the fourth accommodating part It is formed to extend from the side wall of (S4) to the center. The spacing between the first and second protrusions 11a and 11b should be at least larger than the diameter of the plunger 22 to enable the forward/reverse of the plunger 22 of the power unit 20.

A fixed shaft 14-1 protruding upward is formed on the bottom surface of the fourth receiving portion S4 so that the movement transmitting portion 60 and the locking unit 70 are rotatable, and the side surface of the fourth receiving portion S4 is formed. In the fixing groove 15 is formed.

The first return spring (40-1) is a plurality of times the wire rod forms a hollow, and the wound portion (41-1) is wound, and a first angle of the wire rod that extends outside the winding portion (41-1) at a predetermined angle. It consists of an end 42-1 and a second end 43-1. The fixing part 62 is inserted into the hollow of the winding part 41-1, the second end part 43-1 is located in the groove of the support part 64, and the first end part 41-1 is a cover plate ( 11-1) is inserted into the fixing groove 15 formed on one side of the fourth receiving portion S4.

The connecting pin 50 of the second embodiment is the same as the connecting pin 50 of the first embodiment.

The movement transmission unit 60 includes a base 61 having a hollow from the bottom surface and a fixing unit 62 formed to protrude upward on the central axis of the base 61, and a product extending outside the side surface of the base 61 1 extension part 63, the first extension part 63 and a second extension part 65 which forms an angle and extends to the upper side and/or the lower side of the base 61, and the first extension part 63 It is composed of a third extension portion (66) that forms a predetermined angle and extends outside the side surface of the base (61).

The first extension portion 63 includes a first and second fixing shafts 52 and 53 of the connection pin 50 and a longitudinal insertion hole 63a through which the pin head 51 does not penetrate, and the first extension. A supporting portion 64 having a groove is provided on the side of the portion 63.

The second extension portion 65 extends lower than the bottom surface of the base 61 to allow the locking unit 70 to rotate together when the driving transmission unit 60 rotates, and the first and second locking portions spaced apart from each other Parts 65a and 65b are provided.

The third extension portion 66 has an insertion groove 66a into which one end of the second return spring 80 performing the return to the initial position of the locking unit 70 is inserted and fixed.

The locking unit 70 is a base 71 having a hollow 72 formed therein, a rotation limiting portion 73 protruding outward from the side of the base 71, and protruding outward from the side of the base 71 An extension portion 74 facing the through portion P-1 is provided.

The rotation limiting portion 73 is inserted into the space between the first and second locking portions 65a and 65b, and has a width smaller than the width of the space.

The extension portion 74 is fixed to one end of the wheel gear 9, the engaging portion 75 is caught on the tooth (9a), and the other end of the second return spring 80 is inserted and fixed to one side of the extension portion 74 The first and second fixing protrusions 74a and 74b are provided. The first and second fixing protrusions 74a and 74b are formed to be spaced apart by an interval equal to or smaller than the diameter of the second return spring 80.

In the second return spring 80, the wire is wound a plurality of times around the central axis, one end is inserted and fixed in the insertion groove 66a, and the other end is spaced between the first and second fixing protrusions 74a, 74b. Insert is fixed. That is, both ends of the second return spring 80 are spaced between the insertion grooves 66a and the first and second fixing protrusions 74a and 74b spaced apart from the rotation axis of the motion transmitting part 60 and the locking unit 70. Each is connected to a space.

A part of the plunger 22 protruding out of the case 21 is inserted through the insertion hole 63a of the first extension portion 63 and the second fixing shaft 53 is inserted and fixed to the through hole 24, The power unit 20 and the motion transmission unit 70 are connected to transmit power.

In addition, by fixing the shaft 14-1 through the hollow 72, the locking unit 70 is positioned closest to the bottom surface of the fourth receiving portion S4, and the upper end of the fixing shaft 14-1 Since it is rotatably inserted into the hollow formed in the base 61, the rotation axis of the motion transmission unit 70 and the rotation axis of the locking unit 70 are the same. In the stacked structure of the locking unit 70 and the movement transmitting unit 60 from the bottom surface of the fourth receiving unit S4, one end of the second return spring 80 is inserted and fixed to the insertion groove 66a, and the second return The other end of the spring 80 is inserted and fixed in the space between the first and second fixing protrusions 74a and 74b, and the rotation limiting portion 73 is spaced between the first and second locking portions 65a and 65b It is located in space.

A control unit (not shown) for applying a control signal (locking signal, unlocking signal) to the seat belt retractor is provided, and the control unit generates a control signal according to the driving state of the vehicle, the withdrawal state of the webbing, etc. (20).

Next, the operating state of the retractor for seat belts according to the second embodiment is described. First, the initial state (unlocked state) of the retractor for seat belts is described. As shown in Figure 4a, the control unit does not need to apply a control signal to the power unit 20, the plunger 22 by the restoring force (tension) of the first return spring 40-1, the case 21 Advances to the outside of the protruding as much as possible, the movement transmission unit 60 rotates by the forward state or the forward movement of the plunger 22, and the rotational force of the movement transmission unit 60 is the first and second locking portions 65a, 65b) is transmitted to the accommodated rotation limiting portion 73 between the locking unit 70 is also rotated in the same direction as the rotational direction of the movement transmitting portion 60 is located in the initial position. In this initial position, a state in which the engaging portion 75 is spaced apart from the one-way teeth 9a is maintained. Even if the holding portion 25 is pulling the plunger 22, the unlocking state (or initial state) is maintained because the restoring force of the first return spring 40-1 is greater than the attraction force of the holding portion 25.

Next, when locking is required for the wheel gear 9, the control unit applies a locking signal to the power unit 20, a magnetic field is formed in the winding 26 of the power unit 20, and a magnetic force caused by the magnetic field By this, the plunger 22 moves into the case 21 (accommodating space S3), that is, the plunger 22 moves backward, and the backward movement of the plunger 22 is rotated by the motion transmitting unit 60 Converted into motion, the rotational force is transmitted to the locking unit 70. Since the magnetic force formed in the power unit 20 is greater than the restoring force of the first return spring 40-1 (or the restoring force of the first return spring 40-1 and the combined force of the attraction force of the holding unit 25), motion is transmitted. The unit 60 rotates by an angle corresponding to the moving distance of the plunger 22, and the locking unit 70 also rotates in the same direction by rotation of the movement transmitting unit 60, so that the locking unit 75 is toothed in one direction. In contact with (9a), the rotation of the wheel gear 9 is stopped. That is, the withdrawal of the webbing is stopped by the stoppage of rotation of the wheel gear 9. With respect to the rotational angle of the motion transmission portion 60, the distance in the long axis of the insertion portion 63a is equal to or greater than the movable distance (linear movement distance) of the plunger 22. However, the withdrawal of the webbing is stopped in the locked state, but the intake of the webbing is possible and this will be described in detail below.

Next, the control unit stops the application of the locking signal in a state in which the webbing is withdrawn due to the locking state. That is, the magnetic force due to the magnetic field formed in the winding portion 26 is extinguished, but the holding portion 25 is pulling the plunger 22. Since the attraction force of the holding part 25 becomes larger than the restoring force of the first return spring 40-1, the locking state can be maintained.

Next, the control unit applies a unlocking signal to the power unit 20 to release the locked state. The plunger 22 moves in the forward direction by the magnetic force generated by the magnetic field formed in the winding portion 26 of the power unit 20, and the movement transmission unit 60 is rotated by the linear movement of the plunger 22. The unit 70 also rotates in the same direction, so that the locking portion 75 is spaced apart from the one-way teeth 9a to release the locking state. That is, since the magnetic force formed in the power unit 20 and the restoring force of the first return spring 40-1 are greater than the attraction force of the holding unit 25, the motion transmitting unit 60 corresponds to the moving distance of the plunger 22 You can rotate as much as you like.

As described above, the withdrawal of the webbing is stopped by the locking operation, and the withdrawal interruption state is maintained even in the absence of the control signal (locking signal) after the withdrawal of the webbing is stopped. When the strength of the attraction force of the holding portion 25, the restoring force of the first return spring 40-1 and the magnetic force of the power portion 20 in the above-described process are compared, the motion transmitting portion 60 and the engaging unit 70 ), the weight of the plunger 22, etc. should also be considered, but this is only a degree recognized by those skilled in the art to which the present invention pertains, and the description thereof is omitted.

5A and 5B are bottom views of the locking unit after the seat belt retractor of FIG. 3 is assembled. The width of the rotation limiting portion 73 is smaller than the width of the separation space between the first and second locking portions 65a and 65b.

5A shows the locked state, and the rotation limiter 73 is rotated by the first locking portion 65a, so that the locking portion 75 is caught by the one-way teeth 9a so that the wheel gear 9 rotates in the withdrawal direction It doesn't work,

Fig. 5B shows that the webbing can be drawn in the locked state. When the wheel gear 9 rotates in the inlet direction, the rotation limiter 73 rotates while being spaced apart from the first locking portion 65a, and then rotates to stop contact with the second locking portion 65b. During the rotational movement of the rotation limiting portion 73, the engaging portion 75 is moved to the outside of the wheel gear 9 while the engaging portion 75 contacts the outer surface of the one-way teeth 9a by the elastic restoring force of the second return spring 80. Thereby, the locking of the incoming is released. The rotation angle of the locking portion 75 is within an angle corresponding to a length obtained by subtracting the width of the rotation limiting portion 73 from the width of the separation space between the first and second locking portions 65a and 65b. While the rotation of the wheel gear 9 in the direction of intake is progressing, the locking portion 75 is caused by the elastic restoring force of the second return spring 80 when the locking portion 75 passes the outermost portion Mo of the one-way teeth 9a. 75) is moved to the innermost part (Mi) of the one-way teeth (9a), that is, the locking unit 70 is rotated, the rotation limiting part 73 is also moved to contact the first locking portion (65a) to maintain the locked state do. That is, in the case of the retractor for seat belts in the second embodiment, the webbing is prevented from being pulled out in the locked state and has a clutch structure that allows the webbing to be drawn in.

As described above, the present invention is not limited to the specific preferred embodiments described above, and any person having ordinary skill in the art to which the present invention pertains may vary without departing from the gist of the present invention as claimed in the claims. It goes without saying that modifications are possible, and such changes are within the scope of the claims.

1: Retractor for seat belt 2: Frame
3: Spool 9: Wheel gear

Claims (5)

A frame;
A spool rotatably inserted into the frame and the webbing is wound or unwound;
A wheel gear provided on one side of the frame and rotated together according to rotation of the spool and having a plurality of unidirectional teeth formed on an outer circumferential surface;
A unlocking unit for performing a unlocking operation for the withdrawal and pulling direction of the webbing; a locking holding unit for contacting a unidirectional tooth to perform a locking operation for the withdrawal direction of the webbing; and for a withdrawal direction of the webbing according to a control signal. A locking unit comprising an operation unit for performing a conversion between a locked state and a unlocked state;
A retractor for a seat belt, comprising a cover plate that receives the locking unit and is fixed to one side of the frame while covering the wheel gear. According to claim 1,
The operation unit is composed of a plunger and a winding unit that advances and reverses the plunger according to a control signal.
The locking holding part is composed of a holding part preventing contact with a tooth in one direction according to the advance or retraction of the plunger and preventing rotation of the wheel gear in the pulling direction, and a holding part preventing movement of the plunger during the locking operation,
The retractor for seat belts, characterized in that the unlocking portion allows the locking portion to be spaced apart from the tooth in one direction. According to claim 2,
The locking retainer has a movement transmitting unit that performs a rotational movement according to the forward or reverse movement of the plunger, and the rotation axis and the rotational direction of the locking portion are the same as the rotational axis and the rotational direction of the movement transmitting portion, respectively, and in the locking state, the locking portion rotates in the rotational direction of the movement transmitting portion Retractor for a seat belt, characterized in that it is possible to rotate within a predetermined rotational angle in the direction of inlet of the webbing, which is in the opposite direction, so that locking in the inlet direction of the wheel gear is released. The method of claim 3,
The locking portion includes a rotation limiting portion, and the movement transmitting portion includes first and second locking portions formed spaced apart by a separation space, and the rotation limiting portion is located in a separation space between the first and second locking portions, thereby rotating movement of the movement transmitting portion A retractor for a seat belt, characterized in that the width of the separation space is greater than the width of the rotation restriction part located in the separation space, which is transmitted to the locking part through the rotation limiting part contacting the first or second locking part. The method of claim 3,
A retractor for seat belts, characterized in that a return spring connecting each of the locking portion and the driving transmission portion is provided.

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