JP4060408B2 - Stepless adjuster for vehicle seat - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a stepless adjuster attached to a seat device of a vehicle or the like, and more specifically, a vehicle seat used for a stepless reclining device or the like that can adjust a tilt angle of a seat back with respect to a seat cushion steplessly. About the stepless adjuster.
[0002]
[Prior art]
In the seat reclining device disclosed in Japanese Utility Model Publication No. 42-7950, the sector gear is fixed to the seat back, while the sector gear and the detachable worm gear are rotatably attached to the seat cushion. The worm gear is connected to the operating shaft, and the meshing of the worm gear with the sector gear is released by pulling the operating shaft in the axial direction and further lifting it. When a load is applied to the seat back in this state, the seat back tilts and the tilt angle can be changed quickly.When the hand is released from the operating shaft, the worm gear meshes with the sector gear again, and the seat back Held in position. Also, if fine adjustment of the seat back tilt angle is required, rotating the operating shaft and rotating the worm gear will cause the sector gear meshing with the worm gear to gradually rotate, making the seat back stepless to any tilt angle. Can be changed.
[0003]
In the seat reclining device disclosed in Japanese Patent Publication No. 52-9892, a worm wheel is fixed to a seat cushion, and a worm gear is rotatably attached to a seat back and meshed with the worm wheel. In the axial direction of the worm gear, a groove having a width capable of loosely fitting the edge of the worm wheel is engraved, and when the handle connected to the worm gear is rotated, the edge of the worm wheel is fitted into the groove. The meshing between the worm gear and the worm wheel is released, and the seat back can be quickly tilted to an arbitrary position. After changing the inclination angle of the seat back, when the hand is released from the handle, the worm gear is rotated 90 degrees by the spring, and meshes with the worm wheel again to be locked. By gradually rotating the handle, the worm gear integrally rotates and the worm wheel meshing with the worm gear also gradually rotates, so that the inclination angle of the seat back can be finely adjusted.
[0004]
A seat reclining device disclosed in US Pat. No. 4,685,735 includes a seat back bracket pivotally attached to a seat mounting base, a sector gear fixed to the seat back bracket and having spur teeth, and a seat mounting base. And a worm gear that meshes with the sector gear. The worm gear meshing with the spur teeth of the sector gear is inclined with respect to the sector gear by an angle corresponding to the spiral angle, and the angle of the seat back is adjusted appropriately by rotating a knob connected to the worm gear. It has become.
[0005]
Also known is a seat reclining device in which a sector gear is fixed to a seat back frame, a lock gear that meshes with the sector gear is provided, and the mesh angle between the sector gear and the lock gear is manually released to appropriately adjust the inclination angle of the seat back. It is.
[0006]
Furthermore, a taumel type seat reclining device using meshing of an external gear and an internal gear is well known.
[0007]
[Problems to be solved by the invention]
Among those described in the prior art, in the seat reclining device disclosed in Japanese Utility Model Publication No. 42-7950 or Japanese Patent Publication No. 52-9892, the meshing between the worm gear and the sector gear or the worm wheel is released. However, in any configuration, the seat back is always urged to the upright position by the spring, so when the engagement is released, the seat back rapidly There was a problem that the passengers who were seated were discomforted.
[0008]
In addition, in the configuration in which the rotation of the sector gear fixed to the seat back is locked by the lock gear, in addition to the above problems, the teeth formed on the sector gear and the lock gear are formed at a predetermined pitch, and the seat back is slightly There was a problem that it could not be adjusted.
[0009]
Further, in the one disclosed in U.S. Pat. No. 4,685,735 and the Taumel type seat reclining device, the sector gear and the worm gear, or the external gear and the internal gear are always meshed, and the seat back The inclination angle cannot be changed quickly, and there is a problem that it takes time to change the inclination angle.
[0010]
The present invention has been made in view of such problems of the prior art. For example, the present invention is attached to a vehicle seat reclining device or the like, and the inclination angle of the seat back can be adjusted quickly and steplessly. It is an object to provide a stepless adjuster for a vehicle seat that can be reliably locked in position.
[0011]
[Means for Solving the Problems]
In order to achieve the above object, the invention according to claim 1 of the present invention has a worm wheel attached to the member to be adjusted, and a lead angle that meshes with the worm wheel and is equal to or larger than a friction angle of the worm wheel. A worm gear, a roller holding member that is rotatably attached to one end of the worm gear, and holds a plurality of rollers; a roller guide member that guides the roller; and a lock mechanism that prevents the worm gear from rotating. The mechanism locks the worm gear by pressing the roller against one end of the worm gear via the roller holding member and the roller guide member, and operates the lock mechanism to press the roller against one end of the worm gear. By releasing the lock of the worm gear. With adjusting the includes a cam shaft in which the locking mechanism has a first cam and a second cam, while engaging the first cam to the roller retaining member, engages the second cam to the roller guide member And a stepless adjuster for a vehicle seat, wherein the worm gear is locked and unlocked by rotation of the first and second cams .
[0013]
Further, in the invention according to claim 2 , the roller guide member has the same number of recesses as the roller, and the roller guide member is pressed against one end of the worm gear by a portion other than the recess. While the worm gear is locked, the worm gear is unlocked by fitting the roller into the recess.
[0014]
According to a third aspect of the present invention, a pipe spring is provided in parallel with each of the rollers.
[0015]
According to a fourth aspect of the present invention, the member to be adjusted is composed of a seat back that is tiltably attached to a seat cushion of a vehicle seat, and the inclination angle of the seat back can be changed as appropriate. Features.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
1 to 3 show a stepless adjuster A for a vehicle seat according to the present invention, which is attached to, for example, a vehicle seat reclining device or the like.
[0017]
The stepless adjuster A includes a worm gear 2, a worm wheel 4 that is always meshed with the worm gear 2, a worm gear 2 and a worm wheel 4 rotatably accommodated, and a plurality of bolts 6, ..., 6 and nuts (not shown). Are provided with an inner casing 8 and an outer casing 10 that are joined together, and a lock mechanism 12 that locks the worm gear 2. Further, the lead angle of the worm gear 2 is set larger than the friction angle with the worm wheel 4, and the worm gear 2 is rotated by rotating the worm wheel 4.
[0018]
A bearing 14 is interposed between the worm wheel 4 and the inner casing 8, and a bearing 16 and a collar 18 are interposed between the worm wheel 4 and the outer casing 10. The worm wheel 4 is smoothly rotated in the interior 10. On the other hand, the worm gear 2 is rotatably supported by the bearings 22 and 24 accommodated in the bearing holding portions 20 and 20 of the casings 8 and 10 via the collars 26 and 28.
[0019]
As shown in FIG. 4, one end of the worm gear 2 is inserted into a collar 30 that rotates integrally with the worm gear 2, and the collar 30 includes an integrally formed U-shaped lever 32 a and a roller holding portion. The holder 32 is loosely inserted into a circular opening 32c of the holder 32 made of 32b, and is accommodated in the holder case 34 in a swingable manner.
[0020]
As shown in FIGS. 5 and 6, the roller holding portion 32b of the holder 32 has a plurality of (for example, six) protruding portions 32d,..., 32d formed around the circular opening 32c. A pair of side-by-side needle rollers 36 and a pipe spring 38 are accommodated in contact with each other between adjacent protruding portions 32d and 32d, and are formed between the protruding portions 32d and 32d. It faces the collar 30 through the opening 32e.
[0021]
The roller holding portion 32b of the holder 32 has a central opening in the roller guide 40 so that it protrudes somewhat from the roller guide 40 with a pair of needle rollers 36 and a pipe spring 38 held between adjacent protruding portions 32d and 32d. A roller stopper 42 is attached to the end of the roller holding portion 32b that protrudes from the roller guide 40 and prevents the needle roller 36 and the pipe spring 38 from slipping out in the axial direction of the roller holding portion 32b. is doing. The roller guide 40 and the roller stopper 42 are covered with a guide case 44 joined to the holder case 34. The roller guide 40 has an integrally formed U-shaped lever 40b. A cam shaft described later is engaged with the U-shaped lever 40b, and the center opening 40a has the same number as the needle roller 36. Recesses 40c, ..., 40c are formed.
[0022]
As can be seen from FIGS. 1 and 2, the stepless adjuster A for a vehicle seat according to the present invention includes a camshaft 46 including a pair of camshaft halves 46a and 46b extending in parallel with the worm gear 2. The pair of camshaft halves 46a and 46b are joined by an operating lever 48 that also serves as a joint.
[0023]
Each of the camshaft halves 46a and 46b is rotatably supported by a holder case 34 and a guide case 44, and has a first cam 50 and a second cam 52 that are spaced apart from each other by a predetermined distance. The two cams 50 and 52 are loosely inserted into the U-shaped lever 32a of the holder 32 and the U-shaped lever 40b of the roller guide 40, respectively.
[0024]
The operation lever 48 is always urged upward by a spring 54 wound around the camshaft 46.
[0025]
The operation when the stepless adjuster A for a vehicle seat according to the present invention having the above configuration is applied to, for example, a vehicle seat reclining device will be described below. In this case, the stepless adjuster A is attached to the seat by a plurality of bolts 56 shown in FIG. 1 or FIG. 3, and the worm wheel 4 is attached to a seat cushion (not shown) in a tiltable manner. It is connected and fixed to a seat back (not shown) as a member to be adjusted via a key, for example.
[0026]
The worm wheel 4 fixed to the seat back meshes with the worm gear 2, and the rotation of the worm gear 2 is blocked by the operation lever 48, whereby the seat back is held at a predetermined angle with respect to the seat cushion.
[0027]
More specifically, in a normal state where the operation lever 48 is not operated, the operation lever 48 is urged upward by the spring 54 to lock the worm gear 2 in the state shown in FIG. In this state, the side surface of the first cam 50 of the camshaft 46 contacts the inner surface of the U-shaped lever 32a of the holder 32, while the side surface of the second cam 52 contacts the inner surface of the U-shaped lever 40b of the roller guide 40. Thus, the needle rollers 36,..., 36 are frictionally engaged with both the outer surface of the collar 30 that rotates integrally with the worm gear 2 and the inner surface of the central opening 40 a of the roller guide 40, and accordingly the rotation of the worm gear 2. The seat back is prevented from tilting.
[0028]
The interval between the outer surface of the collar 30 and the inner surface of the central opening 40a of the roller guide 40 is gradually narrowed from each concave portion 40c of the roller guide 40 toward the intermediate portion between the concave portion 40c and the concave portion 40c. In the state 5, the needle rollers 36,... 36 bite into the outer surface of the collar 30 and the inner surface of the central opening 40 a of the roller guide 40, so that the worm gear 2 and the seat back are securely locked.
[0029]
On the other hand, when it is desired to change the inclination angle of the seat back, when the operation lever 48 is pressed against the urging force of the spring 54, the camshaft 46 rotates in the direction of arrow P in FIG. As a result, as shown in FIG. 6, the convex portion of the first cam 50 faces upward and comes into contact with the inner surface of the U-shaped lever 32 a of the holder 32 to move the U-shaped lever 32 a upward. It rotates a predetermined angle in the direction of arrow P. On the other hand, the convex portion of the second cam 52 faces downward and comes into contact with the inner surface of the U-shaped lever 40b of the roller guide 40 to move the U-shaped lever 40b downward, so that the roller guide 40 is predetermined in the direction opposite to the arrow P. Rotate the angle. At this time, since the needle rollers 36,..., 36 are held together with the pipe springs 38,... 38 in the holder 32, they rotate integrally with the holder 32, and the roller guide 40 rotates in the opposite direction to the holder 32. , 36 are fitted into corresponding recesses 40c,..., 40c formed in the central opening 40a of the roller guide 40. Accordingly, the friction engagement between the needle rollers 36,..., 36 and the collar 30 is released, and the worm gear 2 can be freely rotated. Therefore, the seat back can be tilted in either the front or rear direction, and the seat back can be tilted. The corners can be changed as appropriate.
[0030]
After changing the inclination angle of the seat back, when the hand is released from the operation lever 48, the camshaft 46 is rotated in the direction of the arrow P by the urging force of the spring 54, and the state shown in FIG.
[0031]
The configuration and operation of the lock mechanism 12 in the above embodiment has been described only with respect to the camshaft half 46a and its related members, but the camshaft half 46b and its related members are symmetrical with respect to FIG. Since the configuration and operation are the same, description thereof is omitted. In addition, both the camshaft half 46a and its related members and the camshaft half 46b and its related members are not necessarily required, and either one can be omitted.
[0032]
【The invention's effect】
Since the present invention is configured as described above, the following effects can be obtained.
According to the first aspect of the present invention, the lead angle of the worm gear is set to be equal to or larger than the friction angle with the worm wheel, and the plurality of rollers are connected to the worm gear via the roller holding member and the roller guide member by the lock mechanism. The worm gear is locked by pressing on one end of the roller, and the lock mechanism is operated to release the worm gear lock by releasing the pressure applied to the end of the worm gear. And can be locked securely at an arbitrary position.
[0033]
Further, the first and second cam formed on mosquito Mushafuto, while engaging the first cam to the roller holding member to engage the second cam roller guide member, the rotation of the first and second cam Since the worm gear is locked and unlocked, it can be locked and unlocked quickly with a small stroke and a small operating force.
[0034]
According to the second aspect of the present invention, the worm gear is locked by pressing the roller against one end of the worm gear at a portion other than the concave portion of the roller guide member, while the worm gear is locked by inserting the roller into the concave portion. Since it is released, there is no backlash at the time of locking, and it can be locked securely.
[0035]
According to the invention described in claim 3 , since the pipe spring is provided in parallel with each of the rollers, the play of the roller can be eliminated by the elastic force of the pipe spring, and the roller can be reliably locked.
[0036]
According to the fourth aspect of the present invention, since the member to be adjusted is constituted by the seat back that is tiltably attached to the seat cushion of the vehicle seat, the inclination angle of the seat back can be changed steplessly and quickly. At the same time, the seat back can be reliably held at a desired angle.
[Brief description of the drawings]
FIG. 1 is a perspective view of a stepless adjuster for a vehicle seat according to the present invention.
FIG. 2 is a perspective view showing a state where a part of the casing of the stepless adjuster of FIG. 1 is removed.
3 is an exploded perspective view of the stepless adjuster of FIG. 1. FIG.
4 is an exploded perspective view of a lock mechanism provided in the stepless adjuster of FIG. 1. FIG.
5A and 5B show a locked state of the locking mechanism of FIG. 4, in which FIG. 5A is a partial cross-sectional perspective view, and FIG. 5B is a side view thereof.
6 shows a state in which the lock mechanism of FIG. 4 is unlocked, (a) is a partial sectional perspective view thereof, and (b) is a side view thereof. FIG.
[Explanation of symbols]
2 Worm gear 4 Worm wheel 12 Lock mechanism 30 Collar 32 Holder 36 Needle roller 38 Pipe spring 40 Roller guide 46 Cam shaft 48 Operation lever 50 First cam 52 Second cam

Claims (4)

A worm wheel that is attached to the member to be adjusted, a worm gear that meshes with the worm wheel and has a lead angle greater than a friction angle with the worm wheel, and a roller holding that is rotatably attached to one end of the worm gear and holds a plurality of rollers A member, a roller guide member that guides the roller, and a lock mechanism that prevents rotation of the worm gear. The lock mechanism causes the roller to be connected to one end of the worm gear via the roller holding member and the roller guide member. While the worm gear is locked by pressing, the lock mechanism is operated to release the pressing of the roller to one end of the worm gear, and the member to be adjusted is adjusted by releasing the lock of the worm gear , The locking mechanism has a first cam and a second cam A camshaft, wherein the first cam is engaged with the roller holding member, the second cam is engaged with the roller guide member, and the rotation of the first and second cams causes the lock of the worm gear and A stepless adjuster for a vehicle seat, wherein the vehicle is unlocked . The roller guide member has the same number of recesses as the roller, and the worm gear is locked by pressing the roller against one end of the worm gear at a portion other than the recess of the roller guide member, while the roller is The stepless adjuster for a vehicle seat according to claim 1 , wherein the worm gear is unlocked by being fitted into the vehicle. The stepless adjuster for a vehicle seat according to claim 1 or 2 , wherein a pipe spring is provided in parallel with each of the rollers. The target adjustment member constituted by a seat back mounted tiltably to the seat cushion of the vehicle seat, according to any one of claims 1 to 3 was set to be appropriately changed inclination angle of the seat back Stepless adjuster for vehicle seats.

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