WEBBING WINDING DEVICE

A webbing winding device includes a spool, a sensor lever, and a solenoid. In a state where the sensor lever is disposed at the first position, the rotation in the drawing-out direction of the spool is enabled, and in a state where the sensor lever is disposed at the second position, the rotation in the drawing-out direction of the spool is locked. When the solenoid is actuated, the sensor lever is displaced from the first position to the second position. The sensor lever is provided with a thinned groove being deformed when a part of the sensor lever disposed at the second position is pressed toward the first position, the thinned groove allowing displacement toward the first position of the part of the sensor lever.

TECHNICAL FIELD

The present invention relates to a webbing winding device.

BACKGROUND ART

Japanese Patent Application Laid-Open (JP-A) No. 2002-2447 discloses a webbing winding device including a lock mechanism that restricts drawing-out from a spool of a webbing (belt) in emergency of a vehicle, such as at the time of rapid deceleration of a vehicle. In the lock mechanism of the webbing winding device described in this document, a locking pawl is engaged with a gear member provided integrally rotatably with the spool. Accordingly, rotation of the gear member is locked and drawing-out from the spool of the webbing is restricted. In the lock mechanism of the webbing winding device described in this document, the locking pawl is displaced toward the gear member by the solenoid being actuated.

SUMMARY OF INVENTION

Technical Problem

Incidentally, in the configuration in which the displacement member such as the locking pawl is displaced by the actuation of the actuation portion such as the solenoid, it is desirable to be able to prevent the displacement member from being difficult to displace toward the original position after the actuation of the actuation portion, for example.

In consideration of the above fact, an object of the present invention is to obtain a webbing winding device capable of preventing it from being difficult to displace the displacement member toward the original position.

Solution to Problem

A webbing winding device according to a first aspect includes: a spool, a webbing to be attached to an occupant being wound around the spool, the spool being rotated in a drawing-out direction by the webbing being drawn out: a displacement member configured to be displaced between a first position and a second position, rotation in the drawing-out direction of the spool being enabled in a state in which the displacement member is disposed at the first position, and rotation in the drawing-out direction of the spool being locked in a state in which the displacement member is disposed at the second position; and an actuation portion, actuation of the actuation portion causing the displacement member to be displaced from the first position to the second position, wherein the displacement member is provided with a deformation allowing portion that is deformed in a case in which a part of the displacement member disposed at the second position is pressed toward the first position, and the deformation allowing portion is allowed to be displaced toward the first position of the part of the displacement member.

In the webbing winding device according to the first aspect, in a webbing winding device according to a second aspect, the displacement member includes an attracting portion that is attracted to the actuated actuation portion. By the deformation allowing portion being deformed in a state in which the attracting portion is attracted to the actuation portion, displacement toward the first position of the part of the displacement member is allowed.

Advantageous Effects of Invention

In the webbing winding device according to the first aspect, when the actuation portion is actuated in an emergency of the vehicle, the displacement member is displaced from the first position to the second position, and the rotation in the drawing-out direction of the spool is locked. As a result, drawing-out from the spool of the webbing is restricted.

Here, in the webbing winding device according to the first aspect, when a part of the displacement member disposed at the second position is pressed toward the first position, the deformation allowing portion is deformed, and the displacement toward the first position of the part of the displacement member is allowed. As described above, in the webbing winding device according to the first aspect, it is possible to prevent the displacement member from being difficult to displace toward the original position.

In the webbing winding device according to the second aspect, when the actuation portion is actuated in an emergency of the vehicle, the attracting portion of the displacement member is attracted to the actuation portion, and the displacement member is displaced from the first position to the second position. Accordingly, rotation in the drawing-out direction of the spool is locked and drawing-out from the spool of the webbing is restricted.

Here, in the webbing winding device according to the second aspect, when a part of the displacement member is pressed toward the first position in a state where the attracting portion is attracted to the actuation portion, the deformation allowing portion is deformed, and the displacement toward the first position of the part of the displacement member is allowed. As described above, in the webbing winding device according to the second aspect, it is possible to prevent the displacement member from being difficult to displace toward the original position.

DESCRIPTION OF EMBODIMENTS

A webbing winding device according to an embodiment of the present invention will be described with reference toFIGS.1to4.

As shown inFIGS.1and2, the webbing winding device10of the present embodiment includes a spool12, a webbing14. and a lock mechanism16. Hereinafter, unless otherwise noted, when the axial direction, the radial direction, and the circumferential direction are simply indicated, the rotational axial direction, the rotational radial direction, and the rotational circumferential direction of the spool12are indicated.

As shown inFIG.1, the spool12is formed in a substantially cylindrical shape. Between a pair of leg pieces18A of a frame18(seeFIG.2), the spool12is rotatably supported by the frame18. A known torsion shaft (not shown) constituting a force limiter mechanism is disposed inside the spool12. A lock base20is provided on one side in the axial direction (arrow Z direction side) of the spool12. The lock base20is coupled to the spool12through the torsion shaft. The spool12is rotationally urged in the winding direction by a winding urging mechanism (not shown).

The webbing14is attached to the body of an occupant seated on a vehicle seat, and has a base end portion, which is one end portion in the longitudinal direction, locked to the spool12. The spool12is rotationally urged in a winding direction (direction of an arrow C inFIG.1and the like) being one rotation direction by an urging force of a spiral spring constituting a part of a winding urging mechanism. Then, the spool12is rotated in the winding direction, whereby the webbing14is wound around the spool12from the base end side. The webbing14is drawn out from the spool12, whereby the spool12is rotated in a drawing-out direction (direction opposite to the arrow C inFIG.1and the like) being the other rotation direction. A winding mechanism such as a pretensioner mechanism that rotates the spool12in the winding direction in an emergency or the like of the vehicle described below may be provided.

Next, the lock mechanism16of the main part of the present embodiment will be described.

As shown inFIG.1, the lock mechanism16includes a main lock22supported by the lock base20and a main lock engagement portion24with which the main lock22is engaged. The lock mechanism16includes a pawl engagement member26as an engagement member provided to be integrally rotatable with the spool12. As shown inFIGS.2and3, the lock mechanism16includes a pawl28and a sensor lever30disposed radially outside the pawl engagement member26, and a solenoid32disposed to face the sensor lever30.

As shown inFIG.1, the main lock22is formed in a substantially rectangular block shape. The base end side of the main lock22is supported in a tiltable manner by a main lock support portion provided on the lock base20. On the radially outer side on the tip side of the main lock22, a main lock engaging tooth22A to be engaged with a main lock tooth to be engaged24A of the main lock engagement portion24described below is formed. Then, the main lock22is tilted (displaced) radially outward with the main lock support portion as a supporting shaft portion, whereby the main lock engaging tooth22A is engaged with the main lock tooth to be engaged24A of the main lock engagement portion24. The main lock22is provided with a cylindrical protrusion22B protruding toward one side in the axial direction.

The main lock engagement portion24is formed in an annular shape as an example, and a plurality of main lock tooth to be engaged24A (ratchet teeth) are formed along the circumferential direction in the inner circumferential portion of the main lock engagement portion24. The main lock engagement portion24may be formed integrally with the frame18(seeFIG.2) that supports the spool12, or may be provided separately from the frame18.

The pawl engagement member26is formed in a disc shape. A radially central portion of the pawl engagement member26is rotatably supported by a torsion shaft (not shown) or a lock base20. On the radially outer side of the portion supported by the torsion shaft (not shown) or the lock base20in the pawl engagement member26, a long hole-shaped actuation groove26A in which the protrusion22B of the main lock22is disposed inside is formed. A plurality of pawl tooth to be engaged26B (ratchet teeth) with which a pawl engaging tooth28D of the pawl28described below is engaged are formed along the circumferential direction in the outer circumferential portion of the pawl engagement member26. The above-described pawl engagement member26is rotationally urged in the drawing-out direction with respect to the lock base20by a coil spring (not shown) provided between the pawl engagement member26and the lock base20, and has the rotation by the coil spring in the drawing-out direction with respect to the lock base20locked.

As shown inFIG.2, the pawl28is supported in a tiltable (rotationally displaceable) manner by the housing34. The housing34is attached to the frame18. A main lock engagement portion24, a main lock22, and the like (seeFIG.1) are disposed inside the housing34.

The pawl28includes a tubular portion28A that is rotatable around a cylindrical first supporting shaft portion34A that is provided in the housing34. by inserting the first supporting shaft portion34A. The pawl28includes a first arm portion28B that protrudes from the other side in the axial direction (side opposite to the direction of arrow Z) of the tubular portion28A toward the outer side in the radial direction of the tubular portion28A. A pawl first abutting portion28C on which a part of the first arm portion30B abuts is formed on the first arm portion30B side of the sensor lever30described below in the tip portion of the first arm portion28B. On the side opposite to the pawl first abutting portion28C in the tip portion of the first arm portion28B, a pawl engaging tooth28D to be engaged with a pawl tooth to be engaged26B (seeFIG.3) of the pawl engagement member26is formed. The pawl28further includes a second arm portion28E that protrudes from one axial side (arrow Z direction side) of the tubular portion28A toward the radially outer side of the tubular portion28A and the side opposite to the direction in which the first arm portion28B protrudes. A pawl second abutting portion28F which abuts on the housing first abutting portion34B (seeFIG.3) of the housing34is formed in a tip portion of the second arm portion28E.

The sensor lever30, as a displacement member, includes a tubular portion30A that is rotatable around a cylindrical second support shaft portion34C that is provided in the housing34, by inserting the second support shaft portion34C. The sensor lever30includes a first arm portion30B that protrudes from one side in the axial direction (arrow Z direction side) of the tubular portion30A toward the outer side in the radial direction of the tubular portion30A. On the pawl first abutting portion28C side of the first arm portion28B of the pawl28in the tip portion of the first arm portion30B. a sensor lever first abutting portion30C as an engagement portion abutting on the pawl first abutting portion28C is formed. As shown inFIG.3, a sensor lever-side spring locking portion30D to which an end portion on one side of the return spring36is locked is formed on the side opposite to the sensor lever first abutting portion30C in the tip portion of the first arm portion30B. An end portion on the other side of the return spring36is locked to a housing-side spring locking portion34D provided in the housing34. Then, the return spring36is deformed along with the tilt of the sensor lever30(tilt toward a second position P2described below), whereby the sensor lever30is urged toward a first position P1described below.

As shown inFIG.2, the sensor lever30includes a second arm portion30E as an attracting portion that protrudes from the tubular portion30A toward the radially outer side of the tubular portion30A and the side opposite to the direction in which the first arm portion30B protrudes. A plate30F as an attracting portion is fixed to the solenoid32side described below in the second arm portion30E. The plate30F is formed in a rectangular plate shape using iron or steel metal as an example, and constitutes a part of the sensor lever30The plate30F may be embedded inside the second arm portion30E. As shown inFIG.3, a sensor lever second abutting portion30G abutting on the housing second abutting portion34E of the housing34is formed in the tip portion of the second arm portion30E and on one side in the axial direction (arrow Z direction side).

The solenoid32as an actuation portion generates a magnetic field when applied with a predetermined voltage and energized (actuated). As an example, the solenoid32is configured by winding a conducting wire around an iron core (a coil is formed around the iron core).

Then, as shown inFIG.3, in a state where the solenoid32is not energized (the solenoid32is not actuated), the sensor lever30takes a predetermined attitude with respect to the housing34. The position of the sensor lever30in this state is referred to as a first position P1. In a state where the sensor lever30is disposed at the first position P1, a state where the sensor lever first abutting portion30C of the sensor lever30abuts on the pawl first abutting portion28C of the pawl28, and a state where the pawl second abutting portion28F of the pawl28abuts on the housing first abutting portion34B of the housing34are brought about, so that the pawl28takes a predetermined attitude with respect to the housing34. The position of the pawl28in this state is referred to as an engagement-release position P3. In the state where the pawl28is positioned at the engagement-release position P3, the pawl engaging tooth28D of the pawl28cannot engage with the pawl tooth to be engaged26B of the pawl engagement member26(is separated from each other).

On the other hand, as shown inFIG.4, when the solenoid32is actuated, the second arm portion30E (plate30F) of the sensor lever30is attracted to the solenoid32, and the sensor lever30is tilted from the first position P1to one side (arrow C1direction side) around the second supporting shaft portion34C. When the sensor lever30is tilted from the first position P1to one side (arrow C1direction side) around the second supporting shaft portion34C, the sensor lever first abutting portion30C of the first arm portion30B of the sensor lever30presses the pawl first abutting portion28C of the pawl28. Accordingly, the pawl28is tilted from the engagement-release position P3toward one side (arrow C2direction side) around the first supporting shaft portion34A, and the pawl engaging tooth28D of the pawl28is engaged with the pawl tooth to be engaged26B of the pawl engagement member26. As a result, the rotation in the drawing-out direction (the drawing-out direction of the spool12) of the pawl engagement member26is restricted (regulated). The position of the pawl28in a state where the pawl engaging tooth28D of the pawl28can engage with the pawl tooth to be engaged26B of the pawl engagement member26is referred to as an engaging position P4. The position of the sensor lever30in the state where the pawl28is positioned at the engaging position P4is referred to as a second position P2.

The direction and magnitude of the attracting force by which the solenoid32attracts the second arm portion30E (plate30F) of the sensor lever30are indicated by an arrow F. The attracting force F is assumed to coincide with the direction from the N pole to the S pole or the direction from the S pole to the N pole which are the directions of the magnetic field generated by the solenoid32.

Functions and Effects of Present Embodiment

Next, functions and effects of the present embodiment will be described.

As shown inFIG.1, according to the webbing winding device10of the present embodiment, the webbing14is drawn out from the spool12, whereby the webbing14is attached to the occupant seated on the vehicle seat.

Here, when an acceleration sensor or the like provided in the vehicle detects that the deceleration/acceleration of the vehicle including the webbing winding device10of the present embodiment exceeds the predetermined deceleration/acceleration (in an emergency or the like of the vehicle), the solenoid32is actuated as shown inFIG.4. When the solenoid32is actuated, the second arm portion30E (plate30F) of the sensor lever30is attracted to the solenoid32, and the sensor lever30is tilted from the first position P1to the second position P2. When the sensor lever30is tilted from the first position P1to the second position P2, the sensor lever first abutting portion30C of the first arm portion30B of the sensor lever30presses the pawl first abutting portion28C of the pawl28. Accordingly, the pawl28is tilted from the engagement-release position P3toward the engaging position P4, and the pawl engaging tooth28D of the pawl28is engaged with the pawl tooth to be engaged26B of the pawl engagement member26. As a result, the rotation in the drawing-out direction (the drawing-out direction of the spool12) of the pawl engagement member26is restricted.

Then, as shown inFIGS.1and4, when the body of the occupant seated on the vehicle seat moves to the seat front side due to the deceleration of the vehicle and the webbing14is drawn out from the spool12, the spool12is rotated in the drawing-out direction together with the main lock22. Accordingly, the protrusion22B of the main lock24is moved along the actuation groove26A of the pawl engagement member26whose rotation is restricted, and the main lock engaging tooth22A of the main lock22is engaged with the main lock tooth to be engaged24A of the main lock engagement portion24. As a result, the rotation in the drawing-out direction of the spool12is restricted (locked), and the drawing-out from the spool12of the webbing14is restricted. Accordingly, the body of the occupant seated on the vehicle seat is restrained by the webbing14.

Incidentally, when the solenoid32is continuously actuated after completion of engagement of the main lock22(main lock engaging tooth22A) with the main lock engagement portion24(main lock tooth to be engaged24A), it is conceivable that displacement (return) toward the first position P1of the sensor lever30is hindered, and displacement (return) toward the engagement-release position P3of the pawl28is hindered. As a result, it is conceivable that the load on the members constituting the lock mechanism16increases and the rotation in the winding direction of the spool12is hindered. Hereinafter, a configuration for preventing or suppressing such a problem will be described.

Configuration for Preventing or Suppressing Above Problem

FIG.5shows a sensor lever30, a pawl28, and a pawl engagement member26to which a configuration for preventing or suppressing the above-described problem is applied. In this figure, illustration of the sensor lever-side spring locking portion30D, the sensor lever second abutting portion30G. and the like of the sensor lever30is omitted. The illustration on the second arm portion28E side in the pawl28is omitted.

As shown inFIG.5, a thinned groove30H as a deformation allowing portion formed in an L shape when viewed from the axial direction is formed in the first arm portion30B of the sensor lever30to which the present configuration is applied. The thinned groove30H includes a first groove portion30H1in which a part of the first arm portion30B is cut out so that the side opposite to the pawl28is opened and the pawl28side is closed. The thinned groove30H includes a second groove portion30H2in which a portion from an end portion on the pawl28side of the first groove portion30H1in the first arm portion30B to the tubular portion30A is cut out.

Then, in the configuration including the thinned groove30H described above, when an excessive force such that the pawl28attempts to return from the engaging position P4toward the engagement-release position P3is input to the pawl28in a state where the sensor lever30is disposed at the second position P2by actuation of the solenoid32being continued, that is, in a state where the plate30F is disposed at a position closest to the solenoid32, the sensor lever30(sensor lever first abutting portion30C) is pressed by the pawl28(pawl first abutting portion28C). Accordingly, as shown inFIG.6, the first arm portion30B of the sensor lever30is deformed from the state indicated by the two-dot chain line to the state indicated by the solid line with the edge portion of the thinned groove30H as the deformation starting point. That is, deformation is made so that the groove interval of the thinned groove30H is narrowed. As a result, only the sensor lever first abutting portion30C side with respect to the portion where the thinned groove30H is formed in the first arm portion30B is displaced to the side opposite to the pawl28(the first position P1side). Accordingly, displacement toward the engagement-release position P3of the pawl28is allowed.

Here, the case where an excessive force such that the pawl28attempts to return from the engaging position P4toward the engagement-release position P3is input to the pawl28is assumed to be a case where an excessive pressing force B2is generated at the contact point between the sensor lever30and the pawl28along with the fact that the spool12is rotationally urged in the winding direction by the urging force of the spiral spring or the like described above.

In the configuration described above, when an excessive force such that the pawl28attempts to return from the engaging position P4toward the engagement-release position P3is input to the pawl28, it is possible to prevent the attracting force F of the solenoid32from hindering the displacement of the pawl28and a part of the sensor lever30respectively toward the engagement-release position P3and the first position P1. In this configuration, it is not necessary to lower the attracting force F of the solenoid32, and the rotation in the drawing-out direction of the spool12can be quickly locked at the time of rapid deceleration of the vehicle.

In the example described above, an example in which the pawl28is configured to be engaged with the pawl engagement member26along with the displacement of the sensor lever30, that is, an example in which the sensor lever30is configured to be indirectly engaged with the pawl engagement member26through the pawl28has been described, but the present invention is not limited thereto. For example, as shown inFIG.7, the sensor lever30may be configured to be directly engaged with the pawl engagement member26. In the sensor lever30shown inFIG.7, a portion corresponding to the above-described pawl28is denoted by the same reference numeral as the portion corresponding to the above-described pawl28.

Although one embodiment of the present invention has been described above, the present invention is not limited to the above, and it is needless to say that various modifications other than the above can be made and implemented without departing from the gist of the present invention.

The disclosure of Japanese Patent Application No. 2020-056845 filed on Mar. 26, 2020 is incorporated herein by reference in its entirety.