JP4245366B2 - Reclining adjuster - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a reclining adjuster that is attached to a seat of a vehicle or the like and appropriately adjusts an inclination angle of a seat back with respect to a seat cushion, and particularly relates to a technique for reducing rattling when the seat back is locked.
[0002]
[Prior art]
In the reclining adjuster disclosed in Japanese Utility Model Publication No. 42-7950, the sector gear (worm wheel) is fixed to the seat back, while the sector gear and the detachable worm are rotatably attached to the seat cushion.
The worm is connected to the operating shaft, and the meshing between the worm and the sector gear is released by pulling the operating shaft in the axial direction and further lifting it.
In this state, when a load is applied to the seat back, the seat back tilts and the tilt angle can be changed quickly.When the hand is released from the operating shaft, the worm meshes with the sector gear again, and the seat back Held in that position.
If fine adjustment of the tilt angle of the seat back is necessary, when the worm is rotated by rotating the operating shaft, the sector gear meshing with the worm gradually rotates, so that the seat back is adjusted to an arbitrary tilt angle. It can be changed steplessly.
[0003]
Recently, as disclosed in Japanese Patent Laid-Open No. 10-217817, a worm having a lead angle greater than a friction angle and a sector gear are respectively attached to a seat cushion and a seat back, and the sector back is tilted to A reclining adjuster has also been proposed in which the worm is rotated to change the inclination angle of the seat back as appropriate.
[0004]
[Problems to be solved by the invention]
However, in the case of a reclining adjuster that has a sector gear and a worm that mesh with each other, the backlash between the tooth surfaces of the sector gear and the worm may cause rattling when the seat back is locked, causing abnormal noise and a feeling of sitting. There has been a problem of falling.
[0005]
In addition, when the shaft of the worm is supported freely by a bearing such as a normal ball bearing, there is a clearance in the thrust direction for smooth operation of the worm, but this clearance becomes loose when the seat back is locked. This is also a cause of abnormal noise and a decrease in seating feeling.
[0006]
On the other hand, Japanese Patent Application Laid-Open No. 2000-342371 discloses a technique for reducing backlash by pressing a sector gear meshing with a worm in the worm direction by a pressing member. However, in order to press the sector gear rotatably supported in the radial direction (worm direction), it is necessary to provide an arc-shaped hole in the sector gear, and a hole corresponding to the bracket supporting the worm is formed, It is necessary to provide a roller member that presses the inner walls of these holes, and the structure is complicated and not suitable for mass production. Further, by pressing the sector gear against the worm, it is possible to reduce the backlash when the seat back is locked and to suppress the backlash of the seat back. However, since the clearance in the thrust direction of the worm cannot be reduced, the problem of rattling when the seatback is locked due to such clearance cannot be solved.
[0007]
The present invention has been made to solve the above-described problems, and has a simple structure suitable for mass production.At the time of seat back locking, not only the backlash is reduced, but also the clearance in the thrust direction of the worm is reduced. An object of the present invention is to provide a reclining adjuster capable of preventing the generation of abnormal noise and further improving the sitting feeling.
[0008]
[Means for Solving the Problems]
To achieve the above object, the reclining adjuster of the present invention is a reclining adjuster,
A worm rotatably attached to the seat cushion and a worm wheel fixed to the seat back and meshing with the worm, and selectively operated to lock or unlock the worm so that it cannot rotate. Having a locking mechanism,
Concave portions are provided on both end surfaces of the worm and inner end surfaces of a pair of support members that support both end portions of the worm, and are formed between the concavities facing the both end surfaces of the worm and the pair of support members. A pair of bearings are formed in the pair of cavities so that the balls can be freely rotated to support the worm so that the worm can rotate freely. It has a pressing means for pressing against the tooth part.
Each of the recesses is preferably formed in a substantially mortar shape having a tapered surface on the inner surface.
The locking mechanism includes an engaging claw that can be engaged with and disengaged from an engaging groove formed on a part of the tooth portion of the worm at one end, and the shaft member is configured to engage and disengage the engaging claw with the engaging groove. The arm member is rotatably supported, and the pressing means is composed of an elastic member that is coupled to the arm member and biases the engaging claw in a direction to engage the engaging groove. It is preferable.
The arm member is formed in a substantially T-shape including a long piece and a short piece, a boundary between the long piece and the short piece is supported by the shaft member, the long piece serves as an operation portion, and the engagement portion is disposed at one end of the short piece. It is preferable that a pawl is formed, and the elastic member includes a spring that is provided between the arm member and an arbitrary fixing portion and is biased in a direction in which the engaging pawl is engaged with the engaging groove.
In this case, it is preferable that the spring is stretched between the other one side end of the short piece of the arm member and a bracket that supports the worm.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in more detail based on the embodiments shown in the drawings.
1 to 3 show a reclining adjuster A according to the present invention, which is attached to a seat cushion (not shown) and constitutes a part of the seat cushion, and a pair of first brackets 1, which are arranged facing each other. 2 and a second bracket 3 attached to a seat back (not shown) and constituting a part of the seat back.
[0010]
A worm 4 is rotatably attached to the first bracket 1, while a worm wheel 5 is fixed to the second bracket 3 and meshes with each other. The worm 4 has a lead angle that is greater than the friction angle with the worm wheel 5. The worm wheel 5 may be a helical gear having teeth on the entire circumference as shown in FIG. 1 or a sector gear.
[0011]
A circular hole 6 is formed in the central portion of the worm wheel 5, and a central shaft 7 loosely inserted in the circular hole 6 is attached to the first bracket 1, and the worm wheel 5 is rotated around the central shaft 7. It is pivotally attached.
[0012]
A slit 8 is formed on one side of the central shaft 7. One end of the balance spring 9 is locked to the slit 8, and the other end is locked to a locking shaft 10 attached to the second bracket 3. Thereby, the seat back supported by the second bracket 3 is always urged forward by the elastic force of the balance spring 9.
[0013]
The front end of the worm 4 is rotatably supported by the front bearing 11, and the rear end is rotatably supported by the rear bearing 12.
Specifically, first, substantially mortar-shaped recesses 15 are respectively formed on both end surfaces of the worm 4 and inner end surfaces of the holders 13 and 14 as a pair of support members fixed to support both end portions of the worm 4. 16 is provided.
As a result, voids are formed between the recesses 15 and 16 facing the worm 4 and the pair of holders 13 and 14, and the steel balls 17 are freely rotatable in the pair of voids. Is stored.
[0014]
In such a configuration, the worm 4 is rotatably supported by the holders 13 and 14 via the balls 17. A pair of holders 13 and 14 and a front portion that rotatably supports the worm 4 by a ball 17 housed in a space between the worm 4 and the concave portions 15 and 16 facing the pair of holders 13 and 14. Rear bearings 11 and 12 are formed, respectively.
[0015]
The reclining adjuster A has a lock mechanism that is selectively operated to lock the worm 4 so that it cannot rotate or to release the lock.
This locking mechanism has an engaging claw 20 that can be engaged with and disengaged from an engaging groove 19 formed in a part of the tooth portion 18 of the worm 4 at one end, and an arm member that has an operation portion 21 at the other end. 22 is provided.
In the present embodiment, the engagement groove 19 is constituted by a number of concave and convex grooves formed in the circumferential direction on the outer peripheral portion of two parallel tooth portions 18 at one end portion of the worm 4.
[0016]
The arm member 22 is formed in a substantially T shape having a long piece and a short piece, and an engagement claw 20 is formed at one end of the short piece.
Further, a pin 24 as a shaft member is inserted into the boss 22A at the boundary between the long piece and the short piece of the arm member 22, and is rotatably supported by the pin 24. The long piece constitutes the operation unit 21. The operation portion 21 is rotated about the pin 24 so that the engagement claw 20 formed in a short piece is engaged with and disengaged from the engagement groove 19 of the worm 4 and locked or unlocked. It is.
That is, when the engaging claw 20 is engaged with the engaging groove 19 by the operation of the arm member 22, the worm 4 and the worm wheel 5 meshing with the worm 4 cannot be rotated, the seat back is locked, and the inclination angle is increased. Fixed. On the other hand, when the engaging claw 20 is detached from the engaging groove 19 by operating the arm member 22, the worm 4 and the worm wheel 5 become non-rotatable and the seat back is unlocked.
An operation knob 23 is formed at the end of the long operation portion 21 of the arm member 22 and is held by a seated person.
[0017]
The lock mechanism of the present embodiment includes a pressing unit that presses the worm 4 against the worm wheel 5.
In this embodiment, the pressing means includes a coil spring 25 as an elastic member that elastically biases the arm member 22.
[0018]
That is, the coil spring 25 has one end attached to an attachment hole 26 formed at the other one end of the short piece of the arm member 22 and the other end fixed to the first bracket 1 as a fixing pin. 27 is attached.
[0019]
The pair of first brackets 1 and 2 includes the pins 28 to 32 of the first bracket 1, the pin 24 fitted to the boss 22 </ b> A of the arm member 22, and the fixing pin 27, and the other first bracket. It is assembled by fitting into the two holes 33-39. The operation knob 23 of the arm member 22 is inserted into a long hole 40 formed in the other first bracket 2.
[0020]
Next, the operation of the reclining adjuster A having such a configuration will be described.
In a normal state in which the arm member 22 is not operated, the arm member 22 is urged in the direction of arrow a in FIG. 1 by the elastic force of the coil spring 25, and the engaging claw 20 formed on one end of the short piece is warm. 4 engaging grooves 19.
In this state, since the rotation of the worm 4 is prevented, the rotation of the worm wheel 5 meshing with the worm 4 is also prevented, and the locked state is maintained in which the inclination angle of the seat back with respect to the seat cushion is maintained. The action of the arm member 22 constituting the lock mechanism in this state and the coil spring 25 as the pressing means will be described later.
[0021]
On the other hand, when the inclination angle of the seat back is desired to be changed, when the arm member 22 is operated and the operating portion 21 is moved in the direction of the arrow b in FIG. The lock is released from the engagement groove 19 and the worm 4 can freely rotate.
[0022]
Here, since the worm 4 has a lead angle greater than the friction angle with the meshing worm wheel 5, the worm 4 rotates when a rotational force around the central axis 7 is applied to the worm wheel 5. For this reason, the seat back is moved forward by the elastic force of the balance spring 9, or the seat occupant is moved backward against the elastic force of the balance spring 9 by applying a backward load to the seat back.
[0023]
When the hand is released from the operation portion 21 (operation knob 23) of the arm member 22 at a desired position, the engagement claw 20 is engaged with the engagement groove 19 by the elastic force of the coil spring 25, and the worm 4 is rotated. Blocked and locked, the seat back tilt angle is kept at the current angle.
[0024]
Here, when the engagement claw 20 of the short piece of the arm member 22 is engaged with the engagement groove 19 of the worm 4, the engagement claw 20 is indicated by the arrow c in FIG. As a result, the worm 4 is forced to move toward the worm wheel 5 by being pressed against the engagement groove 19. Thereby, the tooth part of the worm 4 is pressed against the tooth part of the worm wheel 5.
[0025]
As a result, when the seat back is locked, the backlash between the tooth surfaces of the worm 4 and the worm wheel 5 can be reduced. For this reason, rattling when the seat back is locked based on backlash is suppressed, the generation of abnormal noise is prevented, and a stable seating feeling is obtained.
[0026]
In this configuration, the bearings 11 and 12 that support the worm 4 are configured such that the balls 17 are accommodated in the spaces between the concave portions 15 and 16 facing the worm 4 and the pair of holders 13 and 14. . For this reason, when the axis of the worm 4 moves in a direction approaching the worm wheel 5, the ball 17 also moves along the tapered surfaces of the inner surfaces of the recesses 15 and 16.
[0027]
As a result, when the worm 4 is pressed against the worm wheel 5, the worm 4 is supported while the ball 17 is moved along the tapered surfaces of the inner surfaces of the recesses 15 and 16. As a result, since the worm 4 is also pressed in the thrust direction by the balls 17, the clearance in the thrust direction of the worm 4 is reduced when the seat back is locked, and the back of the seat back due to such clearance and abnormal noise are caused. Generation | occurrence | production can be suppressed and a seating feeling can be improved.
[0028]
In particular, as a structure for reducing backlash when the seat back is locked and reducing the clearance in the thrust direction of the worm 4, a lock mechanism including an arm member 22 and a coil spring 25 is provided, and the bearing 11 that supports the worm 4. , 12 only needs to be configured by housing the ball 17 in the space between the concave portions 15, 16 facing the worm 4 and the pair of holders 13, 14, so that the configuration is simple and suitable for mass production. .
[0029]
As the pressing means, the coil spring 25 is used in the above embodiment, but other springs may be used. Moreover, the shape of the arm member which comprises a locking mechanism is not restricted to the thing of embodiment shown in drawing.
[0030]
【The invention's effect】
The reclining adjuster of the present invention is provided with recesses on both end surfaces of the worm and the inner end surfaces of the pair of support members, preferably provided with substantially mortar-shaped recesses, and facing the end surfaces of the worm and the pair of support members. A pair of bearings that freely rotate and accommodate a ball in a pair of cavities formed between the recesses to form a pair of bearings that rotatably support the worm, while a lock mechanism that locks the worm moves the worm. And a pressing means for pressing the worm wheel.
[0031]
For this reason, when the seat back is locked, the backlash between the tooth surfaces of the worm and the worm wheel can be reduced, the generation of abnormal noise can be prevented, and the seating feeling can also be prevented from being lowered. In addition, when the worm is pressed against the worm wheel, the worm is supported while the ball is moved along the tapered surfaces of the inner surfaces of the two recesses. The clearance of the seat becomes small, and the backlash of the seat back and the generation of abnormal noise caused by the clearance can be suppressed at the same time, and the seating feeling can be further improved. Moreover, since it is a very simple structure, it is suitable for mass production.
[Brief description of the drawings]
FIG. 1 is a schematic front sectional view of a reclining adjuster according to an embodiment of the present invention.
FIG. 2 is a perspective view showing a part of the recliner adjuster being assembled.
FIG. 3 is a perspective view showing an assembled state of the reclining adjuster of the above.
[Explanation of symbols]
A Reclining adjuster 1, 2 First bracket 3 Second bracket 4 Worm 5 Worm wheel 11 Front bearing 12 Rear bearing 13, 14, Holder 15, 16 Recess 17 Ball 19 Engaging groove 20 Engaging claw 22 Arm member 25 Coil spring

Claims (5)

A reclining adjuster,
A worm rotatably attached to the seat cushion and a worm wheel fixed to the seat back and meshing with the worm, and selectively operated to lock or unlock the worm so that it cannot rotate. Having a locking mechanism,
Concave portions are provided on both end surfaces of the worm and inner end surfaces of a pair of support members that support both end portions of the worm, and are formed between the concavities facing the both end surfaces of the worm and the pair of support members. A pair of bearings are formed in a pair of cavities, each containing a ball freely rotating and supporting the worm rotatably,
The reclining adjuster according to claim 1, wherein the lock mechanism includes pressing means for pressing the tooth portion of the worm against the tooth portion of the worm wheel when locked. The reclining adjuster according to claim 1, wherein each of the recesses is formed in a substantially mortar shape having a tapered surface on the inner surface. The locking mechanism includes an engaging claw that can be engaged with and disengaged from an engaging groove formed on a part of the tooth portion of the worm at one end, and the shaft member is configured to engage and disengage the engaging claw with the engaging groove. An arm member rotatably supported;
The reclining adjuster according to claim 1, wherein the pressing means includes an elastic member that is coupled to the arm member and biases the engaging claw in a direction in which the engaging claw is engaged with the engaging groove. The arm member is formed in a substantially T-shape including a long piece and a short piece, a boundary between the long piece and the short piece is supported by the shaft member, the long piece serves as an operation portion, and the engagement portion is disposed at one end of the short piece. A nail is formed,
4. The reclining according to claim 3, wherein the elastic member includes a spring that is provided between the arm member and an arbitrary fixing portion and urges the engaging claw in a direction in which the engaging claw engages with the engaging groove. Adjuster. The reclining adjuster according to claim 4, wherein the spring is stretched between the other one end portion of the short piece of the arm member and a bracket supporting the worm.

Images