JP5311387B2 - Headrest - Google Patents

Description

  The present invention relates to a headrest attached to a driver's seat or a passenger seat of a vehicle.

  The basic function required of a headrest of an automobile wrapped with urethane foam is that it does not move backward, that is, is locked when a rear load is applied to the headrest. On the other hand, it is preferable that the position and inclination of the front and rear can be adjusted according to the posture and the physique, and this adjustment may be performed at the time of forward rotation or at the time of backward rotation. When turning forward during adjustment, it can only be moved with a relatively light force, but its inclination must not change due to sudden acceleration / deceleration or running on rough roads. Therefore, it is necessary to produce a resistance sufficient to withstand this.

  As a simple structure having such a function, there is a so-called coil spring type lock mechanism. This uses a coil spring whose winding inner diameter is several percent smaller than the outer diameter of the shaft, and expands the winding inner diameter and passes it through the shaft to generate a tightening force (this is called the initial locked state. The tightening force is called the initial locking force. In this case, when one end of the coil spring is made free and rotated in the direction to increase the other end, the tightening force increases and the necessary locking force can be output. When the coil spring is rotated in the direction to reduce winding, the coil spring loosens. The tightening force is reduced and it can rotate with a relatively light force.

  The following Patent Document 1 applies this coil spring type locking mechanism to a headrest, and is a gate formed in a gate shape with two struts on a seat back and a horizontal portion that lies substantially perpendicularly from the upper end of the strut. A skeleton frame, which is a skeleton member of a headrest, is rotatably attached to a horizontal portion of a gate-shaped stay. Then, a coil spring having one end connected to the skeleton frame and the other end being free is attached to the horizontal portion in a direction in which the skeleton frame is rolled up when the skeleton frame rotates backward. Thereby, the backward rotation of the skeleton frame is locked with a corresponding force, and the forward rotation can be moved with a relatively light force.

  However, in order to obtain a necessary initial locking force, the coil spring must have a large wire diameter, and it is extremely difficult to pass the coil spring through a bent portion bent by approximately 90 °. For this reason, the wire diameter of the coil spring has to be extremely thin, and the locking force that restricts the backward rotation of the skeleton frame is extremely weak. In addition, a stable locking force cannot be obtained due to variations in the winding inner diameter of the coil spring, the accuracy of the outer diameter of the horizontal portion, and the friction coefficient of both. For this reason, it is desirable that the locking force can be adjusted, but the locking force cannot be adjusted in the above-described prior art.

For this reason, the present inventors have proposed the headrest of Patent Document 2 below. This is intended to adjust the ease of insertion and the locking force by widening or narrowing the wire interval after mounting the coil spring on the horizontal part, or providing a step on the horizontal part to which the coil spring is mounted, It cannot be denied that the structure becomes complicated and the number of parts increases.
JP 08-164035 A Japanese Patent Application No. 2008-058834

  The present invention is different from the conventional one by attaching a coil spring whose winding inner diameter is larger than the outer diameter of the horizontal portion to the horizontal portion, and winding the coil spring after mounting and fixing both ends to the skeleton frame, Even a coil spring with a thin wire diameter is a coil spring type locking mechanism that exhibits a sufficient locking force. Since a coil spring with a thin wire diameter can be used in this way, it is easy to pass through the bent part of the portal stay, and by finely adjusting the extent to which the adjustment end is wound, the coil spring winding inner diameter and the outside of the horizontal part can be adjusted. Even if there is a variation in the accuracy of the diameter, this can be easily absorbed and adjusted to the required locking force accurately. In addition, since a stable locking force can be obtained without depending on the dimensional accuracy of the coil spring and the horizontal portion, it is possible to reduce costs by simplifying assembly and reducing the number of parts.

  Under the above-described problems, the present invention forms a gate shape with the two support columns that are erected on the seat back so as to be height-adjustable and the horizontal support portion that horizontally supports the upper ends of the support columns. A skeleton frame that is attached to the portal frame so as to be able to rotate back and forth or turn back and forth and then fall over, and attached to the gantry frame linked to the skeleton frame, In a headrest having a coil spring that regulates the backward rotation of the skeleton frame by tightening the horizontal part in a direction in which the direction in which the skeleton frame rotates backward is increased, the coil spring is slightly the same diameter as the outer diameter of the horizontal part. The first small-diameter portion has a first small-diameter portion having a large-diameter winding inner diameter and a large-diameter portion having a winding inner diameter that continues to the first small-diameter portion and maintains a sufficient gap with respect to the horizontal portion. Fixed end, which is the end of the large diameter, and adjustment end, which is the end of the large diameter part It is obtained by providing a headrest first small diameter portion and wherein in a state of twisted in a direction to increase the winding up tightens the lateral bridging portion that is fixed to the respective skeletal frame.

  According to the present invention, in the above-described headrest, the second small diameter portion is formed continuously from the large diameter portion, and the end of the second small diameter portion is an adjustment end. The means for changing the phase with respect to the fixed end when the adjusting end is fixed to the skeleton frame, and the position in the circumferential direction can be changed when fixing the fixed end to the skeleton frame. Means, wherein when the skeleton frame comes to the forward and rearward rotation limit positions, the rear wall and the front wall come into contact with the struts of the portal stay, and further rotation is restricted. Item 6 is provided with means for providing a light stopper, which is provided on the frame frame so that when the frame frame is rotated forward by a predetermined angle, the frame frame abuts against the support of the portal stay and the further rotation is lightly restricted.

  According to the first aspect of the present invention, the coil spring is formed with the first small-diameter portion and the large-diameter portion, and the fixed end and the adjustment end, which are the respective ends, are twisted in the direction in which the coil spring is relatively wound to form the skeleton frame. (It will be described later that the function of the coil spring type locking mechanism is exhibited even with this configuration). Therefore, the locking force can be adjusted by fixing the fixed end, adjusting the degree of twisting, and fixing the adjusting end, so that a desired locking force can be obtained even if the wire diameter of the coil spring is thin. For this reason, even when the coil spring is inserted from the end of the support column to reach the horizontal portion, the bent portion can be easily passed, and the winding inner diameter of the coil spring and the outer diameter of the horizontal portion are rough. It ’s enough. Further, since the coil spring has a first small diameter portion and a large diameter portion, the locking force for the backward rotation and the resistance force for the forward rotation can be adjusted similarly to the above by adjusting the number of turns.

  According to the second aspect of the present invention, it is possible to accurately adjust the resistance force of forward rotation. According to the means of claims 3 and 4, the initial locking force, and thus the locking force and resistance force can be easily adjusted. According to the means of claim 5, it is possible to restrict the skeletal frame from moving indefinitely by an impact such as a collision, and according to the means of claim 6, it is possible to set an appropriate angle adjustment range with a retractable headrest and adjust the angle. A large resistance is given at the limit position, and particularly the headrest is prevented from rotating forward by a large force such as a collision, and safety is ensured.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a divided perspective view of the headrest, FIG. 2 is a perspective view, and FIGS. 3 and 4 are cross-sectional views, but the headrest has two struts 1 inserted into the top surface of the seat back so that the height can be adjusted, It is attached to a gate-shaped stay 3 having a gate shape with a horizontal portion 2 that horizontally supports the upper end of the column 1. In general, the portal stay 3 is formed by bending a support pipe 1 and a horizontal portion 2 with a single metal pipe. The headrest is formed by covering the skeleton frame 4 with the outer skin 5 through a foamed material such as urethane. In this structure, the skeleton frame 4 has a shape along the gate-shaped stay 3, and each of them is divided into halves. Are integrated (because they cannot be assembled if they are integrated from the beginning). In the following description, left and right are based on FIG. 1, and top and bottom and front and rear are based on FIG.

  A box 6 that bulges outward is formed at the center of the portion where the skeleton frame 4 lies in the horizontal portion 2, and the skeleton frame 4 is rotated to the portal stay 3 by the left and right side walls 6 a and 6 b of the box 6. Fit as possible. Then, the coil spring 7 is mounted in the box 6 and linked to the box 6, and the coil spring 7 has a first small-diameter portion 8 whose winding inner diameter is the same as or slightly larger than the diameter of the horizontal portion 2, and The first small-diameter portion 8 and the large-diameter portion 9 having a sufficient gap with respect to the horizontal portion 2 are configured. In this example, the end of the first small diameter portion 8 is extended outward to be the fixed end 10, the end of the large diameter portion 9 is extended to the side to be the adjustment end 11, and the fixed end 10 and the adjustment end 11 are respectively boxed. It is fixed to 6.

  The fixed end 10 is fixed to the box 6 by forming a receiving groove 12 on the inner surface of the box 6 and inserting the fixed end 10 therein. On the other hand, the adjustment end 11 is fixed to the box 6 by forming the receiving hole 13 in the right side wall 6b of the box 6 and inserting the adjustment end 11 therein (these are examples and are not limited thereto). Not) FIG. 5 ((a) to (c)) is an explanatory view showing a state in which the coil spring 7 is mounted on the horizontal portion 2, but the coil spring 7 is inserted from the end of the column 1 and passed through the bent portion 3a. It will reach to the horizontal part 2. At this time, the wire diameter of the first small-diameter portion 8 may be small, and the winding inner diameter is the same as or slightly larger than the diameter of the horizontal portion 2, so that the bent portion can be easily passed. However, if a large force is required for passage, passing the fixed end 10 and the adjusting end 11 while twisting the first small-diameter portion 8 in a direction to reduce the winding makes it possible to easily pass the enlarged inner diameter of the winding. it can.

  FIG. 6 ((a) to (c)) is an explanatory view showing a state in which the fixed end 10 and the adjustment end 11 are fixed to the box 6, but the coil spring 7 is mounted on the horizontal portion 2 and the portal stay. 3 is rotated about 90 ° with respect to the skeleton frame 4, and the fixed end 10 is fitted into the receiving groove 12 while being inserted into the receiving groove 12, and then the skeleton frame 4 is shifted to the side so that the adjustment end 11 is received by the receiving hole 13 Fit into. To make this possible, the axial width of the box 6 is made longer than the length of the coil spring 7, and the receiving groove 12 for receiving the fixed end 10 is also a long groove extending in the axial direction.

  When the fixed end 10 and the adjustment end 11 are fitted into the receiving groove 12 and the receiving hole 13, respectively, the first small-diameter portion 8 is in a state of tightening the horizontal portion 2 in order to perform the function of the coil spring type locking mechanism normally. It needs to be. This is because when the coil spring 7 is fixed to the box 6, the fixed end 10 and the adjustment end 11 are twisted by a predetermined angle, and the first small diameter portion 8 is wound up until the horizontal portion 2 is tightened (initial lock state). (In a state of exhibiting the above), it is necessary to be fixed to the receiving groove 12 and the receiving hole 13. FIG. 7 is a cross-sectional view of the horizontal portion 2 showing this, but the positional relationship between the receiving groove 12 and the receiving hole 13 is set so as to exhibit the desired initial locking force described above.

  As described above, when the skeleton frame 4 is to be rotated backward, a predetermined locking force is generated, and when the skeleton frame 4 is rotated forward, a resistance force that does not move due to vibration or the like is generated to exhibit the function of the headrest. Become. However, with such a configuration, when the skeleton frame 4 is rotated backward, the first small-diameter portion 8 tightens the horizontal portion 2, but the large-diameter portion 9 is loosened. Loosening by the large-diameter portion 9 decreases the tightening force of the first small-diameter portion 8 and reduces the locking force accordingly. On the other hand, when the skeleton frame 4 is rotated forward, the resistance is increased in the opposite direction.

  However, the decrease in the locking force and the increase in the resistance force by fixing the fixed end 10 and the adjusting end 11 to the skeleton frame 4 are due to the presence of the large diameter portion 9 having a sufficiently large winding inner diameter with respect to the horizontal portion 2. Its influence is weakened. The reason is that the large-diameter portion 9 serves as a cushioning material that absorbs rotational energy from the adjustment end 11 side. In this respect, the large-diameter portion 9 uses the adjustment end 11 as a kind of free end. It can be said that it acts to behave. However, since it affects the first small diameter portion 8 to some extent, this influence varies depending on the winding inner diameter and the number of turns of the large diameter portion 9. FIG. 9 ((a) to (b)) is an explanatory diagram showing this, but as described above, the larger the winding inner diameter and the larger the number of windings, the smaller the influence. In general, it is said that the resistance force when rotating forward is about half of the locking force when rotating backward.

  On the other hand, when the initial locking force is adjusted, the locking force when the skeleton frame 4 rotates backward (also the resistance force when rotating forward) is also adjusted, so it is preferable that these can be adjusted. FIG. 8 ((a)-(b)) is explanatory drawing which shows the positional relationship of the receiving groove 12 and the receiving hole 13 which makes this possible, In this way, the receiving groove 12 and the receiving hole 13 are made into the circumferential direction. It can be easily achieved by forming a plurality and selecting them appropriately. This also serves to absorb manufacturing errors for each coil spring 7 and has an advantage that the manufacturing accuracy of the coil spring 7 is not required to be so severe. In the above description, it is needless to say that the coil spring 7 is set so that the winding direction is increased when the skeleton frame 4 is rotated backward.

  FIG. 9C is an explanatory view showing another example of the coil spring 7. In this example, the second small-diameter portion 19 is continuously provided adjacent to the large-diameter portion 9, and the end thereof is adjusted to the adjusting end 20. It is what. The winding inner diameter of the second small-diameter portion 19 may be the same as that of the first small-diameter portion 8, but the number of turns of the first small-diameter portion 8 and the second small-diameter portion 20 is adjusted. If the number of turns of the portion 8 is half (when the inner diameter of the winding is the same), the resistance force is also halved, and the resistance force for forward rotation is half of the locking force for backward rotation. According to this, it acts equivalent to the case of using two coil springs that give the locking force for the backward rotation and the resistance force for the forward rotation, and the locking force for the backward rotation and the resistance of the forward rotation. The force can be controlled more finely and accurately.

  The skirt portion 4a in which the skeletal frame 4 covers the support column 1 spreads back and forth as it goes downward, and the skeletal frame 4 can be rotated and adjusted within this interval. Specifically, the limit of backward rotation of the skeleton frame 4 is when the front wall 4aa of the skirt portion 4a hits the support column 1, and the limit of forward rotation is when the rear wall 4ab hits the support column. In particular, even when the skeleton frame 4 is rotated backward due to a strong impact such as a rear-end collision, the front wall 4aa of the skirt portion 4a hits the support column 1 to reliably prevent further backward rotation, thus maintaining safety. It is. In the above example, the horizontal portion 2 is positioned above the skeleton frame 4 and the skeleton frame 4 has a so-called downward swing, but there is no problem even if it is an upward swing or a middle swing.

  Next, the headrest includes a so-called retractable type in which the headrest can be rotated backward and forward at approximately 90 ° in front of the seat back. This is to prevent the driver's view in the driver's seat from being disturbed when the seat is tilted. The present invention can also be applied to this retractable seat back. 10 (a) to 10 (c) are cross-sectional views of the retractable headrest, and FIG. 11 is a cross-sectional view taken along line AA in FIG. 10 (a). The skeleton frame 16 has a shape along this. However, since the skeleton frame 16 needs to be rotated backward over about 90 ° when stored, the groove 17 is formed in the interference portion of the skirt portion 16a of the skeleton frame 16 over this range in order to dodge the support column 15. Is formed.

  This type of headrest also needs to adjust the angle in the front-rear direction, and the limit of rearward adjustment is up to the front wall 16aa of the skirt portion 16a (FIG. 9A). Up to the light stopper 18 provided in Since the light stopper 18 becomes a large resistance that restricts the forward rotation of the skeleton frame 16, the forward rotation cannot be exceeded by a force such as vibration, and safety is ensured. However, when the skeleton frame 16 is rotated forward with a force exceeding the regulation force, the light stopper 18 can be overcome, and the storage position where the rear wall 16ab of the skirt portion 16a hits the support column 15 and has fallen over approximately 90 °. (FIGS. 10B and 10C) can be stored.

It is a fragmentary perspective view of a headrest. It is a perspective view of a headrest. It is a cross-sectional view of a headrest. It is a cross-sectional view of a headrest. It is explanatory drawing of the state which attaches a coil spring to a horizontal part. It is a perspective view of the state which fixes the adjustment end of a coil spring to a booth. It is sectional drawing of the horizontal part which shows the relationship between a receiving groove and a receiving hole. It is sectional drawing of the horizontal part which shows the relationship between a receiving groove and a receiving hole. It is explanatory drawing which adjusts the operation resistance of a frame | skeleton. It is sectional drawing of a storage type headrest. It is AA sectional drawing of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 support | pillar 2 horizontal part 3 portal-shaped stay 3a bent part of heel 4 frame frame 4a skirt part 4aa front wall of skirt part 4ab rear wall of skirt part 5 skin 6 box 6a left side wall 6b right side wall 7 Coil spring 8 バ ネ first small-diameter portion 9〃 large-diameter portion 10 first small-diameter portion fixed end 11 large-diameter portion adjustment end 12 receiving groove 13 receiving hole 14 portal stay 15 strut 16 skeleton frame 16a skirt portion 16aa Front wall of skirt part 16ab の 後 Rear wall 17 Groove 18 Light stopper 19 Adjusting end of second small diameter part 20

Claims (6)

  A gate-shaped stay that forms a gate shape with two struts standing upright on the seat back so that the height can be adjusted, and a horizontal portion that horizontally spans the upper end of the strut, and forward / backward rotation or forward / backward rotation with respect to the horizontal portion A frame frame that is attached to the gate-shaped frame so that it can fall and turn after moving, and is attached to the horizontal frame linked to the frame frame, so that the direction in which the frame frame rotates backward is increased in the direction of winding. In the headrest having a coil spring that tightens the part and regulates the backward rotation of the skeleton frame, the coil spring has a first small diameter part having a winding inner diameter that is the same as or slightly larger than the outer diameter of the horizontal part, and a first small diameter part A large-diameter portion having a winding inner diameter that keeps a sufficient gap with respect to the horizontal portion, and a fixed end that is an end of the first small-diameter portion and an adjustment end that is an end of the large-diameter portion To roll up until the first small diameter part tightens the horizontal part Headrest being characterized in that each fixed to the skeletal frame in a state of twisted in.   The headrest according to claim 1, wherein a second small diameter portion is formed continuously with the large diameter portion, and an end of the second small diameter portion is used as an adjustment end.   The headrest according to claim 1 or 2, wherein the phase with respect to the fixed end can be changed when the adjustment end is fixed to the skeleton frame.   The headrest according to any one of claims 1 to 3, wherein the position in the circumferential direction can be changed when the fixed end is fixed to the skeleton frame.   The headrest according to any one of claims 1 to 4, wherein when the skeleton frame comes to the front and rear rotation limit positions, the rear wall and the front wall abut against the support of the portal stay and further rotation is restricted.   The headrest according to any one of claims 1 to 5, wherein a light stopper is provided on the skeleton frame so that when the skeleton frame is rotated forward by a predetermined angle, the frame frame is abutted against a support of the portal stay and further rotation is lightly restricted.