Seat belt device

Abstract

To make it possible to stably restrain a waist of a vehicle occupant on a seat.SOLUTION: In a seat belt device which comprises a webbing 1 and a tongue 2 which is attached to the webbing 1 so as to make it possible to slide and moreover is engaged to a buckle by being inserted into the buckle, it is further provided with a webbing lock 3 which is attached to a body 21 of the tongue 2 so as to be relatively displaceable and removable. The webbing lock 3 is configured so as to lock immovably by pressing the webbing 1 against the tongue 2 when the webbing 1 is pulled up in a shoulder direction in such a state as to attach the tongue 2 to the buckle.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a seat belt device. [Background technology]

[0002] The commonly used three-point seat belt system restrains the occupant from the shoulders to the waist and the areas on both sides of the waist by inserting a tongue on the webbing into a buckle on the side of the seat.

[0003] For example, Patent Document 1 describes that by making the webbing thicker than other areas and providing a protrusion in the insertion hole of the tongue, it is possible to prevent the webbing from turning over at the insertion hole, thereby improving the safety of occupants and providing a seat belt device that is easy for occupants to put on. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 6138716 (JP 2015-178302) Summary of the Invention [Problem to be solved by the invention]

[0005] In the above-mentioned Patent Document 1, there is a gap between the folded-back portion of the webbing of the tongue and the thickness of the webbing, which raises concerns that the occupant's waist may not be restrained easily in the seat.

[0006] In view of the above circumstances, an object of the present invention is to provide a seat belt device that can stably restrain the waist of a vehicle occupant to a seat. [Means for solving the problem]

[0007] The present invention is a seat belt device comprising a webbing, and a tongue slidably attached to the webbing and inserted into a buckle to engage with the buckle, further comprising a webbing lock that is removably attached and displaceable relative to a body of the tongue, and the webbing lock is configured to press the webbing against the tongue and lock it immovably when the webbing is pulled up toward the shoulder with the tongue attached to the buckle.

[0008] According to this configuration, when the webbing is pulled up toward the shoulder due to acceleration occurring in the vehicle or an occupant, or when the webbing or webbing lock is pulled up toward the shoulder at the occupant's discretion, the webbing can be quickly locked by the webbing lock so that it cannot be moved.

[0009] As a result, the occupant's waist is tightly restrained in the seat by the webbing, allowing the occupant to steer the vehicle stably and contributing to reducing fatigue.

[0010] In addition, when the occupant pulls down the webbing or the webbing lock at will, the webbing can be quickly put into an unlocked state in which it can be moved freely, thereby releasing the tightness around the occupant's waist in the seat and allowing the occupant to change their posture freely in the seat.

[0011] In the above seat belt device, the tongue may include a body having an insertion hole through which the webbing is inserted, and a plate provided to protrude downward from the underside of the body, and the body may have horizontally elongated upper and lower beam portions arranged parallel to one another in the vertical direction. The webbing lock may include first and second bars arranged parallel to one another in the width direction of the upper beam portion and spaced apart from one another so as to position the upper beam portion so as to allow vertical displacement, a third bar arranged parallel to one another in the width direction of the second bar and spaced apart from one another on the lower beam portion, a first side plate to which one longitudinal end of each of the first to third bars is coupled, and a second side plate to which the other longitudinal end of each of the first to third bars is coupled, and the third bar may be provided with a wedge-shaped projection protruding toward the underside of the upper beam portion.

[0012] According to this configuration, when the webbing or the webbing lock is pulled toward the shoulder, the third bar is brought close to the upper beam-like portion of the tongue, causing the third bar and the upper beam-like portion to tightly pinch the webbing, causing the protrusion of the third bar to bite into the webbing, resulting in a locked state in which the webbing cannot be moved.

[0013] On the other hand, when the webbing or the webbing lock is pulled down from the locked state, the third bar is moved away from the upper beam-like portion and the protrusion of the third bar is separated from the webbing, resulting in an unlocked state in which the webbing can be freely moved between the third bar and the upper beam-like portion.

[0014] Furthermore, in the above seat belt device, the protrusions may be formed long and along the longitudinal direction of the third bar, and may be provided at multiple locations spaced apart in the width direction of the third bar.

[0015] In this configuration, the force with which the protrusion bites into the webbing is stronger, and the retention force in the locked state is improved compared to when the protrusions are provided at multiple locations spaced apart in the longitudinal direction of the third bar.

[0016] Furthermore, in the above-described seat belt device, a bulging portion that bulges outward in the width direction of the third bar is provided on the inner surface of the third bar facing the first bar, and the protrusion can be configured to be provided on the upper surface of the bulging portion along the entire longitudinal direction.

[0017] According to this configuration, the force with which the projections bite into the webbing is increased, and therefore the force with which the locked state is maintained is improved compared to when the projections are provided intermittently.

[0018] Furthermore, in the above seat belt device, the front surface in the expanding direction of the bulging portion is an inclined surface that gradually bulges diagonally upward from below, and the upper region of the surface of the lower beam-shaped portion of the tongue that faces the third bar is an inclined surface that gradually reduces the thickness of the lower beam-shaped portion toward the upper end of the lower beam-shaped portion, and the inclined surface of the bulging portion can be configured to come into surface contact with the inclined surface of the lower beam-shaped portion when the webbing lock is in an unlocked state.

[0019] According to this configuration, when the webbing lock transitions from a locked state to an unlocked state, the inclined surface of the bulge portion comes into surface contact with the inclined surface of the lower beam-shaped portion of the tongue, and the webbing lock is received by the lower beam-shaped portion of the tongue.

[0020] As a result, when the webbing lock is in the unlocked state, the webbing lock is positioned at a position that is not too far away from the tongue, and therefore, when the webbing is pulled up toward the shoulder from the unlocked state, the webbing can be quickly transitioned to the locked state. [Effects of the Invention]

[0021] According to the present invention, it is possible to provide a seat belt device that can stably restrain the waist of a vehicle occupant to a seat. [Brief explanation of the drawings]

[0022] [Figure 1] 1 is an exploded perspective view showing an embodiment of a seat belt device according to the present invention. [Figure 2] FIG. 2 is a perspective view of a seat belt device. [Figure 3] FIG. [Figure 4] FIG. [Figure 5] This is a cross-sectional view of the line (5)-(5) in Figure 4, seen from the direction of the arrow, showing the unlocked state. [Figure 6] FIG. 3 is a cross-sectional view showing a locked state of the seat belt device. DETAILED DESCRIPTION OF THE INVENTION

[0023] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0024] An embodiment of the present invention is shown in Figures 1 to 6. The seat belt device shown in the figures is attached to a vehicle seat and acts to restrain the occupant when acceleration occurs in the vehicle or the occupant.

[0025] This seat belt device includes a webbing 1 called a seat belt, a tongue 2, a webbing lock 3, and the like.

[0026] As is well known, the webbing 1 is made of flexible synthetic fibers woven into a strip shape.

[0027] As is well known, the tongue 2 is removably engaged with a buckle (not shown) disposed on the side of a seat (not shown).

[0028] The body 21 of the tongue 2 is formed in a horizontally elongated elliptical shape, and is provided with a horizontally elongated insertion hole 21a extending along the longitudinal direction at the center in the short side direction of the body 21. The webbing 1 is inserted through the insertion hole 21a.

[0029] Here, the region of the body 21 above the insertion hole 21a will be referred to as the "upper beam-like portion 21b," and the region of the body 21 below the insertion hole 21a will be referred to as the "lower beam-like portion 21c."

[0030] 5 and 6, upper beam portion 21b has an oval cross section, while lower beam portion 21c has an upper half region that is triangular in cross section, tapering gradually upward, and a lower half region that is rectangular in cross section.

[0031] In addition, the inclined surface 21d facing the third bar 33 in the upper half region of the lower beam-shaped portion 21c is inclined so that the thickness of the lower beam-shaped portion 21c gradually decreases toward the upper end of the lower beam-shaped portion 21c.

[0032] Furthermore, the center line 200 running along the vertical direction of the lower beam-shaped portion 21c is inclined at a predetermined angle θ to the left side of Figure 5 with respect to the center line 100 running along the vertical direction of the upper beam-shaped portion 21b, so that the upper end of the lower beam-shaped portion 21c is positioned opposite the left end of the underside of the upper beam-shaped portion 21b at a predetermined distance.

[0033] At the longitudinal center of the lower beam portion 21c, a protruding piece 22 of an insert plate (not shown) that is insert-molded into the body 21 is provided so as to protrude downward.

[0034] The protruding piece 22 is made of a rectangular plate and has an engagement hole 22a that is engaged with the buckle (not shown).

[0035] The webbing lock 3 is attached to the body of the tongue 2 so as to be relatively displaceable and detachable, and includes first to third bars 31 to 33 and first and second side plates 34, 35.

[0036] The first to third bars 31 to 33 each have a cross-sectional shape like a vertically long rod. The first bar 31 and the second bar 32 are arranged parallel to each other in the width direction and spaced apart from each other, and the third bar 33 is arranged below the second bar 32 and parallel to each other and spaced apart from each other.

[0037] The first bar 31 and the second bar 32 have a plurality of ribs 31a and 32a provided on their inner surfaces (facing each other).

[0038] The ribs 31a, 32a are provided at multiple locations at equal intervals in the longitudinal direction on the inner surfaces of the first bar 31 and the second bar 32. The number of ribs 31a, 32a is, for example, six, but can be set arbitrarily.

[0039] The ribs 31a of the first bar 31 and the ribs 32a of the second bar 32 are provided to protrude toward each other. The opposing distance W1 between the rib 32a of the first bar 31 and the rib 32a of the second bar 32 is set to be slightly smaller than the maximum width W2 of the upper beam-shaped portion 21b of the tongue 2.

[0040] A bulging portion 33a that bulges outward in the width direction of the third bar 33 is provided in the middle region in the longitudinal direction of the inner surface of the third bar 33 (the surface facing the first bar 31).

[0041] On the upper surface of the bulging portion 33a, wedge-shaped protrusions 33b are provided at multiple adjacent locations spaced apart parallel to the short side of the bulging portion 33a, extending along the entire longitudinal direction of the bulging portion 33a. The protrusions 33b protrude toward the lower surface of the upper beam portion 21b. The number of protrusions 33b is, for example, two, but can be set arbitrarily.

[0042] The front surface of the bulging portion 33a in the bulging direction is an inclined surface 33d, which is inclined so as to gradually bulge obliquely upward from the bottom.

[0043] As will be described later, this inclined surface 33d is configured to come into surface contact with the inclined surface 21d on one side of the lower beam-shaped portion 21c of the tongue 2 when the webbing lock 3 transitions from the locked state of Figure 6 to the unlocked state of Figure 5, thereby allowing the webbing lock 3 to be received by the lower beam-shaped portion 21c of the tongue 2.

[0044] In this way, when the webbing lock 3 is in the unlocked state, the inclined surface 33d of the bulging portion 33a and the inclined surface 21d on one side of the lower beam-shaped portion 21c are positioned so that the webbing lock 3 is not too far away from the tongue 2. Therefore, when the webbing 1 is pulled up toward the shoulder from the unlocked state, a quick transition to the locked state is possible.

[0045] Screw holes 31b, 32b, 33c (see FIGS. 5 and 6) are provided at both longitudinal ends of each of the first to third bars 31 to 33. Screws 36 (see FIG. 1) for joining both longitudinal ends of each of the first to third bars 31 to 33 to the first and second side plates 34, 35 are screwed into these screw holes 31b, 32b, 33c.

[0046] The first and second side plates 34, 35 are formed in the same shape and are provided with a plurality of through holes (not shown, reference numerals omitted) through which the aforementioned screws 36 are inserted. The heads of the screws 36 are set larger in diameter than the through holes.

[0047] The webbing lock 3 having such a configuration is designed so that its assembly and attachment to the tongue 2 can be performed simultaneously.

[0048] An example of the assembly and attachment will be described below. First, one longitudinal end of each of the second and third bars 32, 33 of the webbing lock 3 is connected to the first side plate 34 with a screw 36, and then the other longitudinal end of each of the second and third bars 32, 33 is connected to the second side plate 35 with a screw 36.

[0049] With the rib 32a of the second bar 32 against one side of the upper beam-shaped portion 21b of the tongue 2 (the right side in Figure 5), the rib 31a of the first bar 31 is brought close to the other side of the upper beam-shaped portion 21b of the tongue 2 (the left side in Figure 5), and both longitudinal ends of the first bar 31 are connected to the first and second side plates 34, 35 with screws 36.

[0050] This allows the webbing lock 3 to be assembled and attached to the tongue 2 at the same time, as shown in FIG.

[0051] The webbing 1 is adapted to be inserted through the insertion hole 21a between the opposing upper beam portion 21b and the opposing lower beam portion 21c of the tongue 2, between the opposing first bar 31 of the webbing lock 3 and the opposing lower beam portion 21c of the tongue 2, and between the opposing second bar 32 and the opposing third bar 33 of the webbing lock 3.

[0052] Next, the operation of the seat belt device having the above-described configuration will be described with reference to FIGS.

[0053] When the tongue 2 is attached to a buckle (not shown), it is in an unlocked state as shown in FIG. 5, and the webbing 1 can be moved freely.

[0054] In this unlocked state, when acceleration is generated in the vehicle or occupant and the webbing 1 is pulled up in the shoulder direction (see the solid black arrow in Figure 6), or when the occupant intentionally pulls the webbing 1 up in the shoulder direction, the webbing lock 3 is moved upward (in the locking direction, see the hollow arrow in Figure 6) while being guided by both side surfaces of the upper beam-shaped portion 21b of the tongue 2, and the bulging portion 33a of the third bar 33 is brought closer to the upper beam-shaped portion 21b of the tongue 2, and the webbing 1 is tightly sandwiched between the bulging portion 33a and the upper beam-shaped portion 21b, so that the protrusion 33b of the bulging portion 33a bites into the webbing 1, resulting in a locked state (see Figure 6) in which the webbing 1 cannot be moved.

[0055] When the occupant intentionally pulls down and loosens the webbing 1 from the locked state shown in Figure 6, or moves the webbing lock 3 in the unlocking direction (downward), the bulging portion 33a of the third bar 33 moves away from the upper beam-shaped portion 21b of the tongue 2, and the protrusion 33b of the bulging portion 33a moves away from the webbing 1, resulting in an unlocked state (see Figure 5) in which the webbing 1 can move freely between the bulging portion 33a and the upper beam-shaped portion 21b.

[0056] The webbing lock 3 can be removed from the tongue 2 by removing the screw 36. This makes it possible to attach the webbing lock 3 to the tongue of an existing seat belt device at a later time.

[0057] As described above, according to the embodiment to which the present invention is applied, the webbing lock 3 for locking the waist of an occupant with one touch is removably attached to an existing seat belt device, so that when the webbing 1 is pulled up toward the shoulder due to acceleration of the vehicle or occupant, or when the webbing 1 or the webbing lock 3 is pulled up toward the shoulder at the occupant's discretion, the waist can be quickly locked with the webbing 1 fastened. This firmly restrains the waist of the occupant in the seat, enabling the occupant to steer the vehicle stably and contributing to reducing occupant fatigue.

[0058] In addition, when the occupant pulls down the webbing 1 or the webbing lock 3 at will, the webbing 1 can be quickly put into an unlocked state in which it can be moved freely. This allows the occupant's waist to be released from the fastening in the seat, allowing the occupant to freely change their posture in the seat.

[0059] The present invention is not limited to the above-described embodiments, but can be modified as appropriate within the scope of the claims and the equivalents thereto.

[0060] (1) In the above embodiment, an example is given in which screws 36 are used to attach both ends of the first to third bars 31 to 33 in the longitudinal direction to the first and second side plates 34, 35, but the present invention is not limited to this.

[0061] For example, although not shown, it is possible to provide locking portions such as claws and locked portions such as hooks that are engaged with the claws by snap-fitting (a form of engagement that utilizes elasticity) on each of the longitudinal ends of the first to third bars 31 to 33 and the first and second side plates 34, 35, and to attach each of the longitudinal ends of the first to third bars 31 to 33 to the first and second side plates 34, 35 by means of the locking portions and the hooks. This type of configuration also provides the same effects and advantages as the above embodiment.

[0062] (2) In the above embodiment, the protrusion 33b is provided on the upper surface of the bulging portion 33a along the entire longitudinal direction of the bulging portion 33a, but the present invention is not limited to this.

[0063] For example, although not shown, it is possible to provide projections 33b at multiple locations on the upper surface of the bulging portion 33a in the longitudinal direction of the bulging portion 33a so that the projections 33b are spaced apart from one another. This configuration also provides the same effects and advantages as the above embodiment. [Industrial Applicability]

[0064] The present invention can be suitably used in a seat belt device. [Explanation of symbols]

[0065] 1. Webbing 2 Tongue 21 Body 21a Insertion hole 21b Upper beam 21c Lower beam part 21d Slope 22 Projection piece 22a Engagement hole 3 Webbing Locks 31 First Bar 31a Rib 31b screw hole 32 2nd Bar 32a Rib 32b screw hole 33 Third Bar 33a bulge 33b protrusion 33c screw hole 33d slope 34 First side plate 35 Second side plate

Claims

1. A seat belt device comprising: a webbing; and a tongue slidably attached to the webbing and inserted into a buckle to be engaged with the buckle, a webbing lock attached to the tongue body so as to be displaceable relative to the tongue body and removably attached to the tongue body; The seat belt device is characterized in that the webbing lock is configured to press the webbing against the tongue and lock it immovably when the webbing is pulled up toward the shoulder with the tongue attached to the buckle.

2. The seat belt device according to claim 1, the tongue includes a body having an insertion hole through which the webbing is inserted, and a plate provided so as to protrude downward from the underside of the body, and the body has horizontally elongated upper and lower beam-like portions arranged parallel to each other above and below, the webbing lock comprises first and second bars arranged parallel to and spaced apart from each other in a width direction of the upper beam portion so as to position the upper beam portion so as to be displaceable in the up-down direction; a third bar arranged parallel to and spaced apart from each other below the second bar and arranged opposite the lower beam portion; a first side plate to which one longitudinal end of each of the first to third bars is coupled; and a second side plate to which the other longitudinal end of each of the first to third bars is coupled; and the third bar is provided with a wedge-shaped protrusion that protrudes toward a lower surface of the upper beam portion.

3. The seat belt device according to claim 2, The seat belt device is characterized in that the protrusion is formed long and extends along the longitudinal direction of the third bar, and is provided at multiple locations spaced apart in the width direction of the third bar.

4. The seat belt device according to claim 2 or 3, a bulging portion that bulges outward in a width direction of the third bar is provided on an inner surface of the third bar facing the first bar, The seat belt device is characterized in that the protrusion is provided on the upper surface of the bulging portion along the entire longitudinal area.

5. The seat belt device according to claim 4, The front surface of the bulging portion in the bulging direction is an inclined surface that gradually bulges obliquely upward from below, an upper region of a surface of the lower beam-shaped portion of the tongue facing the third bar is an inclined surface such that the thickness of the lower beam-shaped portion gradually decreases toward an upper end of the lower beam-shaped portion, A seat belt device characterized in that, when the webbing lock is in an unlocked state, the inclined surface of the bulging portion is configured to come into surface contact with the inclined surface of the lower beam-like portion.

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