JPH0444097Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) The present invention relates to a latch buckle for a seat belt that is installed on the seats of automobiles and other means of transportation.
In particular, the present invention relates to the seat belt latch buckle, which is capable of disengaging the tongue member with a small amount of operating force and is excellent in operability and safety without causing loss of inertia even when an impact is applied.

(Prior Art) Conventionally, many seat belt buckles have been used in which a handle provided on the buckle body is moved up and down in order to remove a tongue member sewn to the end of the belt from the buckle body. However, buckles with this type of structure have many problems in terms of operability, so recently, instead of this, the tongue member can be removed from the buckle body by simply pressing a part of the pusher member exposed on the front of the buckle body with a fingertip. Latch buckles for seat belts that can be quickly released are widely used.

By the way, this type of conventional latch buckle generally has a latch member provided with a claw portion that locks the tongue member and is biased by a spring in the locking direction.
If the spring force of the latch spring against the latch member is reduced in an attempt to reduce the operating force at the time of release, the locking force between the tongue member and the latch member will weaken, and if the latch member receives an abnormal impact such as a vehicle collision, the latch member will A phenomenon in which the tongue member is easily pulled out from the buckle body due to inertia displacement occurs, so-called inertia slip-off, and conversely, if the spring force on the latch member is set large to prevent this inertia slip-off, the tong member may easily pull out from the buckle body when released. This has had the paradox of increasing the required operating force, making it difficult to operate in the event of an emergency evacuation.

In order to overcome the problems of increased release force and loss of inertia during impact, which conventional seat belt latch buckles had, the latch member moves from the tongue member locking position to the release position in conjunction with the push member. A control member is provided that is slidably displaced between a position that prevents the tongs from moving upward to the side and a position that allows the upward movement in the same direction. A latch buckle for a seat belt designed to prevent the member from unexpectedly moving in the direction of disengaging the tongue member due to inertial force associated with a high impact, etc. is disclosed in, for example, Japanese Utility Model Application Publication No. 106411/1983.

(Problem to be Solved by the Invention) However, even in the above-mentioned improved latch buckle, the latch member is normally always biased by a spring with a constant force in the direction in which the claw portion engages with the tongue member. In addition, until the tongue member is engaged with the buckle, the ejector biased by the ejector spring is interposed between the claw portion and the frame bottom plate and held in the non-engaged position. When the tong member is released by pressing the pusher member, the urging force of the spring that urges the latch member (hereinafter referred to as the latch spring) and the direction in which the tongs are pushed out (releasing direction) by the eject spring are combined. The inventors found that there is a tendency for the force to be momentarily balanced, which acts as resistance and dulls the operating feel, and that there is room for further improvement in this respect.

Of course, it is possible to set a large difference in spring force between the latch spring and the eject spring in advance, but for example, if the spring force of the latch spring is set small and the spring force of the eject spring is set large, There is a problem in that the biasing force in the direction of engagement of the tongue against the latch member is insufficient, which impairs the accuracy of the engagement operation, and requires a large force when inserting the tongue member into the buckle. If the biasing force of is set much larger than the eject spring,
This is not preferred because a large force is required to release the tongs, which reduces the operability of the buckle.

The present invention was devised by focusing on the problems that conventional seat belt latch buckles had. By increasing and decreasing the spring force, a difference is created in the spring force with the eject spring, and the operability of the latch buckle is improved.

(Means for Solving the Problems) The structure of the present invention for achieving the above object will be explained with reference to the accompanying drawings FIGS. 1 to 4.

The latch buckle for a seat belt of the present invention is installed between a U-shaped frame 4 of a buckle body A into which a tongue member 1 is inserted and removed, and both side walls of the frame 4, and a claw portion 5 engages with the tongue member 1. a latch plate 6 that can be raised and rotated between a position where the tong member 1 is released and a position where it is released from the tong member 1; and a bottom plate 4a of the frame 4;
a push member 8 that elastically slides in parallel with the latch plate; a position that is attached to the upper surface of the latch plate 6 so as to be relatively slidable and engages with the push member 8 to prevent the latch plate 6 from moving upward; A control member 7 that can be slidably displaced between a position that allows the member to move up and down, and a control member 7 that is slidably provided along the bottom plate 4a of the frame 4 and that buckles the tongue member 1 with an eject spring 9. The ejector 10 is biased in the direction of extrusion from the main body A.

Further, between the latch plate 6 and the push member 8, when the push member 8 is in the return position,
When the latch plate 6 is biased with a required force in the tongue member engagement direction and the push member 8 is pushed and elastically slid in the release direction, the biasing force against the latch plate 6 disappears and becomes inactive. A latch spring 25 is interposed which is engaged so as to be fixed.

(Function) In the seat belt latch buckle of the present invention having the above configuration, before the tongue member 1 is engaged with the buckle main body A, while the push member 8 is in the return position, the latch spring 25 as shown in FIG. Since the support points at both ends of the latch plate are separated and in a tensioned state, the latch plate 6 is urged in the engagement direction by the action of the latch spring 25.

Next, in this state, as shown in Figure 2, the buckle body A
When the tongue member 1 is inserted against the biasing force of the eject spring 9, the latch spring 2
The latch plate 6 in a state of being biased by the ejector 10 is rotated in the engagement direction by the retracting movement of the ejector 10, and its claw portion 5 is fitted into the locking hole 3 of the tong member 1. Connect to the buckle body A. Also,
At this time, the control member 7 attached to the latch plate 6 so as to be slidable relative to the latch plate 6 is shifted to a position that prevents the latch plate 6 from moving upward, so that the inertia force in the upward movement direction due to the high impact is applied to the latch plate 6. Even if it acts on
The engagement between the two is maintained, thereby preventing the buckle from unintentionally disengaging.

On the other hand, when the push member 8 is pressed and slid in the release direction with a fingertip as shown in FIG. 3 in order to detach the tongue member 1 from the buckle body A when getting off the vehicle, first, as the push member 8 moves, the control is performed. The member 7 engages with this and moves to a position that allows the latch plate 6 to move up and down, and the latch spring 2
The support points at both ends of the latch plate 5 move closer to each other and the biasing force of the latch spring 25 disappears, resulting in a large difference between the force in the engagement direction of the latch plate 6 and the force of the eject spring 9. Even when the spring force 9 is small, the latch plate 6 rotates in the release direction without being hindered by the latch spring 25, and the tongue member 1 is smoothly released from the claw portion 5 of the latch plate 6 and ejected by the ejector 10. It can be done.

(Example) Hereinafter, an example of the present invention will be described in detail based on the accompanying drawings.

Figures 1 to 4 show an example of the latch buckle of the present invention. In these figures, 1 is a tongue member, which has a belt insertion hole 2 at its wide end as usual, and the other narrow end. It has a locking hole 3 in the width tongue part. 4 is a U-shaped frame of the buckle main body A into which the narrow tongue portion of the tong member 1 is inserted and removed, and the buckle main body A is assembled using the frame 4 as a strength member.

As shown in an exploded perspective view in FIG. 4, the buckle main body A includes a U-shaped frame 4 made of a thick metal plate having a U-shaped cross section with side walls 4b and 4c standing up from both sides of a bottom plate 4a; A latch plate 6 is supported between both side walls of the frame 4 so that it can be raised and lowered, and is provided with a claw portion 5 at the center of the lower surface that can fit into the locking hole 3 of the tongue member 1, and a required stroke for the latch plate 6. a control member 7 that is attached so as to be relatively movable at the frame 4 and limits the raising and lowering movement of the latch plate 6;
a pusher member 8 that can be pressed and elastically slid parallel to the bottom plate 4a of the holder, an ejector 10 that ejects the tongue member 1 released from the latch plate 6 from the frame 4 by an eject spring 9, and a pusher member 8 that moves the pusher member 8 in the return direction. , that is, the two main springs 11 and 11' biasing in the direction of arrow u, and the main spring 1
1, 11' and a spring receiving member 12 that supports the fixed end side of the eject spring 9, and a cover member 13 that surrounds each of these members.

The frame 4 has a guide hole 14 in its bottom plate 4a for guiding the ejector 10 along the insertion/removal direction of the tongue member 1, and
Fan-shaped windows 17, 17' which extend toward the rear from the portions closer to the tongue insertion side in both side walls 4b, 4c and which extend laterally from both sides of the latch plate 6 through the extending portions 17, 17'; Support holes 19 and 19' for inserting and supporting support shafts 18 and 18' that protrude laterally from the latch plate 6 are provided, respectively, and a spring receiving member is provided at the rear upper side along with the guide hole 14. Recesses 20, 20' are provided for supporting 12.

The fan-shaped windows 17, 17' have an extension portion 1 of the latch plate 6 extending downward from the upper side thereof.
Projections 22, 22' extend into through holes 21, 21' formed in holes 6, 16'.

The latch plate 6 is bent into an L shape with the axes of the support shafts 18, 18' as boundaries, and has a convex portion 23 projecting vertically upward from the support shafts 18, 18', and the pusher. Between the latch plate 6 and the hook part 24 provided at the rear end of the member 8, the latch plate 6 is moved in the direction in which the claw part 5 approaches the frame bottom plate 4a, that is,
Latch spring 25 that biases rotation in the direction of arrow X
is installed.

The length between the engaging parts 25a and 25b provided at both ends of the latch spring 25 is equal to the hook part 24 on the push member 8 side and the convex part 23 on the latch member 6 side when the tongue release operation is completed. When the push member 8 reaches the return position shown in FIGS. 1 and 2, the latch plate 6 is attached with the required force in the direction of the arrow X. When the pusher member 8 is pressed and slid with the tongs as shown in FIG. 3, play is generated between the engaging portion 25a and the hook portion 24, and the spring force is dissipated. . Further, the biasing force of the latch spring 25 is set to be smaller than the resultant force of the two main springs 11, 11'.

The control member 7 integrally has elevation prevention pieces 26, 26' on both sides thereof, which are large enough to close the through holes 21, 21' of the latch plate 6, and the upper surface of the latch plate 6. The latch plate 6 is attached so as to be slidable with a predetermined stroke along the tongue insertion/removal direction, and is interposed between a hook 27 bent upward from the center and a hook 28 formed at the front end of the latch plate 6. The provided tension spring 29 constantly biases the latch plate 6 in the tongue insertion/removal direction, that is, in the direction of the arrow U in FIG. 3. On the other hand, the pusher member 8 has a front end surface configured as a pressing surface 8a that can be pressed from the outside, and a lower vertical surface that is a contact surface 8b that can come into contact with the contact portion 30 of the control member 7. is formed.

Further, the ejector 10 provided on the frame bottom plate 4a can be displaced within a predetermined sliding range by inserting and removing the tongue member 1, but the sliding range on the front end side is limited to the extent of the tongue push-out operation. At least a portion of the latch plate 6 is interposed between the claw portion 5 of the latch plate 6 and the frame bottom plate 4a at the terminal end to prevent the latch plate 6 from rotating in the tongue locking direction indicated by the arrow X in FIG. It's summery.

The seatbelt latch buckle of the present invention has the above-mentioned configuration. Next, its function will be explained with reference to FIGS. 1 to 3. FIG. 1 shows a tongue member attached to the buckle body A. The latch plate 6 is shown in a disengaged state before the ejector 1 is inserted, and the latch plate 6 rotates about the support shafts 18 and 18' in the direction of arrow Y against the latch spring 25, and the ejector 1
0 is located on the lower surface of the claw part 5, and the arrow X on the latch plate 6
It controls rotation in the direction.

At this time, the control member 7 is biased in the direction of the arrow U by the tension spring 29, but the latch plate 6
The projections 22, 22' are indented in the through holes 21, 21', and the front ends of the elevation prevention pieces 26, 26' are in contact with the rear edges of the projections 22, 22'. ,
Movement in the same direction is blocked, and the stroke is stopped in the middle. In addition, the latch spring 25 is such that the push member 8 is connected to the main spring 1.
1 and 11', it is in the return position shown in the figure.
Since the pusher member 8 is extended in the direction of the arrow U by the hook portion 24, the reaction force therebetween urges the pusher member 8 to rotate.

Next, when the tong member 1 is inserted into the buckle body A from this state as shown in FIG. In order to retract, the latch plate 6 rotates in the direction of arrow X about the support shafts 18, 18' by the action of the latch spring 25, and the claw portion 5 engages in the locking hole 3 of the tong member 1 and the tong member 1 is retracted. Connect member 1 to buckle body A. Also, at this time, the elevation movement prevention piece 2 of the control member 7
6, 26' are the projections 2 as the latch plate 6 is displaced.
2, 22' and moves in the direction of the arrow u by the action of the tension spring 29, closing the through holes 21, 21' of the latch plate 6, and the lower ends of the through holes 21, 21' Since they are held facing each other and held downward and their rotation in the direction of the arrow Y is restricted, the tongue member 1 and the buckle body A are prevented from unintentionally coming apart.

FIG. 3 shows the state when the tong member 1 is removed from the buckle body A. First, in the state shown in FIG.
When a is pressed in the direction of arrow v with a finger, the control member contact surface 8b of the push member 8 engages with the contact portion 30 of the control member 7, and the control member 7 is pulled by the tension spring 29.
, the elevation prevention piece 2 is displaced in the direction of the arrow v against the
6, 26' from above the through holes 21, 21' of the latch plate 6, and the protrusions 22, 26' to the through holes 21, 21'.
At the same time, the hook portion 24 that hooks one end of the latch spring 25 moves in the direction of the arrow v, and the biasing force of the latch spring 25 disappears, causing the gap between the latch spring 25 and the ejector spring 9 to disappear. Since there is a difference in spring force between the two, the latch plate 6 is rotated in the direction of arrow X by the spring force of the eject spring 9 without being hindered by the latch spring 25.

In this way, the latch plate 6 has its claw portion 5 displaced upward and comes out of the locking hole 3 of the tong member 1, and at the same time, the tong member 1 is pushed by the ejector 10 and ejected from the buckle body A. The ejector 10 comes into contact with the lower surface of the claw portion 5 of the latch plate and holds the latch plate 6 in the upper retracted position until the tong member 1 is inserted again. In addition, the push member 8
When the pressing force is released, the push member 8 is moved in the direction of the arrow U by the force of the main springs 11, 11' and returns to its original position (the state shown in FIG. 1).

As described above, the tongue member 1 attached to one side of the seat belt can be smoothly engaged with the buckle body A, and can be released with a small operating force.

(Effects of the invention) As described above, the seat belt latch buckle of the present invention has a control member slidably attached to the latch plate that locks the tongue member 1 to prevent the tongue from moving upward when the tongue is locked. In the buckle, the latch spring that biases the latch plate in the engagement direction is placed between the rear end of the push member 8 and the latch plate. and push member 8
When the latch spring is pressed in the direction of releasing the tongs, the biasing force of the latch spring disappears and becomes inactive due to the proximity of the support points at both ends of the spring, so the spring constant of the latch spring is set large, and Even if the spring force of the eject spring is set small, the latch spring becomes inactive when the tongs are released, and a difference in spring force is created between the two, so the release force is stable and the release operation is light. In addition, when the tongues are engaged, the spring force of the latch spring acts normally in the direction of engagement of the latch plate with the required magnitude, so that the engagement operation of the latch plate is ensured, and the control member It has the excellent effect of preventing inertia from falling out and greatly improving the safety of the buckle by combining dust.

Moreover, according to the present invention, since the latch spring becomes inactive when the tongs are released, it is possible to set the spring force of the eject spring to the minimum necessary, and it is also expected to have the effect of making the operation feel better when inserting the tongs. can.

[Brief explanation of the drawing]

1 to 3 are side sectional views showing an example of the seat belt latch buckle of the present invention, in which FIG. 1 shows the state before engagement, FIG. 2 shows the state when engaged, and FIG. 3 shows the disengagement operation. The status at the time of completion is shown. Also,
FIG. 4 is an exploded perspective view of the seat belt latch buckle. 1... Tong member, 3... Locking hole, 4... Frame, 4a... Bottom plate, 4b, 4c
...Side wall, 5...Claw portion, 6...Latch plate, 7...
Control member, 8... Push member, 9... Eject spring, 10... Ejector, 25... Latch spring, A... Buckle body.

Claims (1)

[Scope of utility model registration request] Between the side walls of the U-shaped frame of the buckle body into which the tong member is inserted and removed, there is provided a latch that can be raised between a position where the claw part engages with the locking hole of the tong member and a position where it is disengaged from the tong member. A board is installed across the board, and
The latch plate is biased by a latch spring in a direction in which the claw portion thereof engages with the tongue member, and the upper surface of the latch plate is brought into contact with a push member that presses and slides elastically parallel to the bottom plate of the frame. A control member is attached so as to be relatively slidable between a position where the latch plate is prevented from moving upwardly and a position where the latch plate is allowed to move upwardly; In the seat belt latch buckle, the latch spring is interposed between the latch plate and the rear end of the push member, and the latch spring is disposed between the latch plate and the rear end of the push member. At least one of both ends of the latch plate is engaged with the latch plate and the push member so that when the push member is pressed and slid in the direction of releasing the tongue member, the spring force thereof disappears and becomes inactive. A latch buckle for seat belts.