JP2001171400A - Seat lifter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a seat lifter that is small, light and inexpensive. SOLUTION: When a handle 3 is turned in a first direction A to rotate a first and a second pole 30A and 30B around the axis of rotation X of the handle 3, a cam 36 separates the second pole 30B from a ratchet wheel 26 while leaving only the first pole 30A engaged with the ratchet wheel 26 to thus allow the ratchet wheel 26 to turn and next to lift a seat cushion. The distance L1 from the axis of rotation X of the handle 3 to the axis of swing Y1 of the first and second poles 30A and 30B is shorter than the distance L2 from the axis of rotation X to that portion of each pole 30A and 30B which is in contact with the cam 36.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seat lifter for adjusting the height of a seat cushion.

[0002]

2. Description of the Related Art Seat lifters for adjusting the height of a seat cushion of a seat installed in an automobile, a railroad vehicle, an aircraft, a ship, a theater, a general house or an office are conventionally known. Such a seat lifter is designed to raise and lower a seat cushion to a height desired by a occupant by rotating a handle, and this type of conventional seat lifter has a large-sized structure, and accordingly, the weight thereof is increased. And was not spared the disadvantage of rising costs.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a sheet lifter which eliminates the above-mentioned conventional disadvantages.

[0004]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a handle shaft rotatably supported on a lifter support, and a handle shaft rotatable relative to the handle shaft. A supported handle; first and second pawls which revolve around the axis of rotation when the handle is rotated and which can swing about its own swing axis; and coaxially with the handle shaft. A ratchet wheel fixed to the handle shaft, a rotating body arranged concentrically with the handle shaft, and allowing the rotation of the handle shaft to be transmitted to the rotating body, but allowing the rotating body to rotate from other than the handle shaft. A brake means for inhibiting rotation of the rotating body when force is applied; and a transmission means for converting rotation of the rotating body into a lifting / lowering operation of a seat cushion, wherein the first and second pumps are provided. The pawls of the first pawl can engage the teeth of the ratchet wheel at different positions in the circumferential direction of the ratchet wheel, and the pawls of the first pole engage the teeth of the ratchet wheel. In this state, when the first pole revolves in the first direction, the pawl of the first pole meshes with the teeth of the ratchet wheel to rotate the ratchet wheel in the first direction, and When the first pawl revolves in a second direction opposite to the first direction while the pawls of the first pawl are engaged with the teeth of the ratchet wheel, the pawls of the first pawl become ratchet wheels. Setting the relative position of the pivot axis of the first pole and the pawl portion of the first pole that engages the teeth of the ratchet wheel so that the ratchet wheel does not rotate by sliding against the teeth of the first pole; The said When the second pawl revolves in the second direction in a state in which the pawls of the pawl are engaged with the teeth of the ratchet wheel, the pawls of the second pawl mesh with the teeth of the ratchet wheel to engage with the teeth of the ratchet wheel. When the ratchet wheel is rotated in the second direction, and the second pole revolves in the first direction with the pawl of the second pole engaged with the teeth of the ratchet wheel,
The second pole engages the pivot axis of the second pole and the teeth of the ratchet wheel so that the pawl of the second pole does not slide against the teeth of the ratchet wheel to rotate the ratchet wheel. When the relative position of the pawl portion of the pawl is set and the handle in the neutral position is rotated in the first direction, the first and second pawls that have been engaged with the teeth of the ratchet wheel up to that time are rotated. Swinging the second pawl so that the pawl of the second pawl of the pawl is separated from the teeth of the ratchet wheel and disengaged therefrom,
And when the handle in the neutral position is rotated in the second direction, the first pole of the first and second pawls of the first and second pawls that have been engaged with the teeth of the ratchet wheel up to that time. A cam for swinging the first pawl such that the pawl is separated from the teeth of the ratchet wheel and disengaged from the teeth, and a swing axis of the first and second pawls from a rotation axis of the handle; L1 and the first and second abutments on the cam from the rotation axis of the handle.
When the distance between the pole and the cam contact portion is L2, L
The present invention proposes a sheet lifter characterized in that the distances L1 and L2 are set so that 1 <L2.

At this time, a guide member having an arc-shaped elongated hole formed around the rotation axis of the handle is slidably fitted in the elongated hole, and the first and second guide members are slidably fitted in the elongated hole. A pole support member that supports the pole swingably,
Advantageously, each end of the slot is configured to serve as a stop for the pole support (claim 2).

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a side view schematically showing a seat arranged in a vehicle cabin. The seat shown here has a seat cushion 1 that supports the buttocks of the occupant, and a seat back 2 that supports the back of the occupant, and the seat cushion 1 has a seat cushion frame that forms its skeleton. By operating the handle 3 of the seat lifter, the height is adjusted as described later.

The seat cushion 1 includes a seat track 4
The seat track 4 has a lower rail 4A fixed to the floor panel 5 and an upper rail slidably mounted in the longitudinal direction along the lower rail 4A. 4B, and
The seat cushion 1 is supported by the upper rail 4B as described later. Upper rail 4B to lower rail 4
A by sliding the seat cushion 1
Can be adjusted and moved in the front-rear direction (the left-right direction in FIG. 1). The seat cushion 1 may be fixedly supported on the floor panel 5 directly without passing through the seat track 4.

FIGS. 2 to 4 show the handle 3 shown in FIG.
FIG. 3 is a side view showing an example of a pinion 6 that is driven to rotate by rotation of the pinion, an example of a transmission unit that converts the rotation of the pinion 6 into an elevating operation of the seat cushion 1, and a lifter support 8. , The handle 3 and a transmission mechanism for transmitting rotation of the handle 3 to the pinion 6 are not shown. Further, most of the transmission means shown in FIGS. 2 to 4, the lifter support 8, the pinion 6, and the transmission mechanism for transmitting the rotation of the handle 3 to the pinion 6 are covered by covers not shown in these figures. The handle 3 is exposed outside the cover as shown in FIG.

The lifter support 8 shown in FIG. 2 to FIG.
The lifter support 8 is made of a rigid body such as a metal plate or a hard resin plate, and forms a part of the seat cushion frame. The pinion 6 is rotatably supported by the lifter support 8 via an element described below.

On the lifter support 8, a sector gear-shaped rack 11 meshing with the pinion 6 is rotatably supported via a support shaft 10. The base rails of the first and second support links 12 and 13 are rotatably supported via pins 14 and 15 on the upper rail 4B of the seat track 4 shown in FIG. 12,
The free end side of 13 is rotatably connected to the lifter support 8 via pins 16 and 17. Further, each end of the connection link 20 is rotatably connected to the rack 11 and the second support link 13 via pins 18 and 19, respectively.

FIG. 2 shows a state in which the seat cushion 1 occupies an intermediate position in the vertical direction, FIG. 3 shows the seat cushion 1 at the highest position, and FIG. 4 shows the seat cushion 1 at the lowest position. Respectively.

The handle 3 shown in FIG. 1 has a base 3A.
And a handle 3B having a handle 3B extending in the radial direction from the base 3A.
And the handle 3 can be rotated. now,
Assuming that the seat cushion 1 is at the intermediate position shown in FIG. 2, when the steering wheel 3 is rotated in the first direction (clockwise direction indicated by the arrow A in the example of FIG. 1) in this state, the rotation will be described later. Is transmitted to the pinion 6 and the pinion 6
Also rotates in the first direction A (clockwise direction in FIG. 2). For this reason, the rack 11 rotates counterclockwise in FIG. 2 around the support shaft 10 and moves the connecting link 20 to the left in FIG. As a result, the first and second support links 12, 13 rotate counterclockwise around their respective base ends, and as shown in FIG.
The lifter support 8, which is connected to 13, ie, the entire seat cushion 1, rises.

On the other hand, in a state where the seat cushion 1 is at the intermediate position shown in FIG. 2, the handle 3 shown in FIG. 1 is moved in a second direction opposite to the first direction (in the example of FIG. When the pinion 6 is rotated (in the counterclockwise direction shown), the pinion 6 shown in FIG. 2 also rotates in the second direction B, that is, in the counterclockwise direction.
As a result, the rack 11 rotates clockwise in FIG. 2 around the support shaft 10, and the connecting link 20 moves to the right in FIG. As a result, the first and second support links 12 and 13 rotate clockwise about their base ends, whereby the seat cushion 1 descends as shown in FIG.

FIGS. 2 to 4 show the structure of one side in the width direction of the seat cushion 1 (the direction perpendicular to the plane of FIG. 1 to FIG. 4). A support, a rotating body that rotates similarly to the rack 11,
And a second support link, and a connection link having each end pivotally connected to the second support link and the rotating body. The rack 11 is fixed to one end of the support shaft 10,
The support shaft 10 is rotatably supported by the lifter support 8 and the lifter support on the other side, and extends in the width direction of the seat cushion 1. The above-described rotating body is fixed to the other end of the support shaft 10. Have been. Therefore, when the pinion 6 rotates as described above, the rotating body on the other side of the seat cushion 1, the connecting link, and the first and second links are
The rack 11 shown in FIGS.
Then, the same operation as the first and second links 12 and 13 is performed, whereby the seat cushion 1 can be raised or lowered in a stable state.

As described above, the first and second support links, the rack, the rotating body, the support shaft, and the connecting link constitute an example of a transmission means for converting the rotation of the pinion 6 into the operation of lifting and lowering the seat cushion 1. ing.

Transmission means other than those shown in the figures may be appropriately employed. In the seat lifter shown in FIGS. 2 to 4, the seat cushion 1 is moved up and down by the rotation of the pinion 6. However, a rotating body other than the pinion is used, and the rotation of the rotating body is used to raise and lower the seat cushion 1. It can also be configured to convert to As described above, the seat lifter of the present example includes the lifter support 8, the handle 3, the pinion 6 as an example of the rotating body, and the transmission means for converting the rotation of the rotating body into a lifting operation of the seat cushion 1. are doing.

FIG. 5 is a sectional view showing an example of the handle 3 and a transmission mechanism for transmitting the rotation of the handle 3 to the pinion 6.
Is an exploded sectional view thereof. FIG. 7 shows the transmission mechanism in FIG.
Is a diagram viewed from the right side of FIG.
FIG. 8 is a view showing the handle 3 by a chain line, and FIG. 8 is a view showing each of some elements of the transmission mechanism.

As can be seen from FIGS. 5 and 6, the seat lifter has a handle shaft 21. The handle shaft 21 includes a support piece 8A fixed to the lifter support 8 and a brake device 9 described later in detail. And is rotatably supported by the lifter support 8 via the. A handle joint bracket 22 and a handle bracket 23 are fixed to the handle 3 with a plurality of screws 24. The handle joint bracket 22 and the handle bracket 23 are made of a plate material, and a center hole 25 of the handle bracket 23 is rotatably fitted to the handle shaft 21. As described above, the handle 3 is supported by the handle shaft 21 via the handle joint bracket 22 and the handle bracket 23 so as to be relatively rotatable with respect to the handle shaft 21. The handle joint bracket 22 and the handle bracket 23 are omitted, and the handle 3 is connected to the handle shaft 2
1 may be directly rotatably supported. The handle 3 and the handle shaft 21 rotate around the common rotation axis X.

A ratchet wheel 26, which is arranged concentrically with the handle shaft 21, is fixed to the handle shaft 21. The pinion 6, which is an example of the rotating body shown in FIGS. 2 to 4, is shown in FIG. Is arranged concentrically with the handle shaft 21 as described above. The above-described brake device 9 allows the rotation of the handle shaft 21 to be transmitted to the rotating body composed of the pinion 6, but when a rotating force is applied to the rotating body other than the handle shaft, the rotating body rotates. It has a function of prohibiting the operation, and its specific configuration will be described later in detail.

The sheet lifter further has a guide member 27 made of a thin plate. The guide member 27 has a pair of arms 27A as shown in FIGS. 7 and 8, and each arm 27A is shown. And is fixed to the lifter support body 8 by means of no screws.
The handle shaft 21 has entered. As shown in FIGS. 7 and 8, the guide member 27 has an arc-shaped long hole 29 formed about the rotation axis X of the handle 3, and the first and second poles are formed in the long hole 29. First and second pole supporting members 31 respectively supporting 30A and 30B
A and 31B are slidably fitted along the elongated holes 29. The pole support members 31A and 31B of this example are constituted by pins, and the respective tips of the pole support members 31A and 31B are formed in the holes 32A and 3
2B (FIG. 8) and is fixed here. The first and second poles 30A and 30B have holes 33A and 33B (FIG. 8) formed in the first and second poles 30A and 30B, respectively.
Are rotatably fitted to the pole support members 31A and 31B. In this way, the pawls 30A and 30B are swingably supported by the pawl support members 31A and 31B,
At this time, the swing axes Y1 and Y2 serving as the swing centers are the center axes of the respective pole support members 31A and 31B.

As described above, the first and second pole supporting members 31A and 31B are fixed to the handle 3 via the handle bracket 23.
1A, 31B may be directly fixed to the handle 3, or the first and second pawls 30A, 30B may be directly swingably supported by the handle 3 without the intermediary of the pole supporting members 31A, 31B. Is also good. In any case, as shown in FIG. 7, the first and second pawls 30A and 30B are positioned such that their respective swing axes Y1 and Y2 are separated from the rotation axis X of the handle 3 by a distance L1 in the radial direction. Therefore, when the handle 3 rotates, the first and second pawls 30A and 30B revolve around the rotation axis X which is the center of the rotation. Moreover, the first and second poles 30A, 30B
Are supported by the handle 3 via other elements (or directly) so as to be swingable about their own swing axes Y1 and Y2.

As shown in FIG. 7, the claws 34A, 34B of the first and second pawls 30A, 30B are in contact with the teeth 35 on the peripheral surface of the ratchet wheel 26 in the circumferential direction of the ratchet wheel 26. Each can be engaged at a different position.

As shown in FIGS. 7 and 8, a cam 36 is formed on the outer periphery of the above-described guide member 27. It is formed by expanding in the radial direction from the outer peripheral portion of the member. On the other hand, the first and second poles 30
A and 30B have protrusions 37A and 37B that are in sliding contact with the outer peripheral portion of the guide member 27 including the cam 36. Further, the pawl portions 34A and 34B of the first and second pawls 30A and 30B are surely brought into contact with the teeth 35 of the ratchet wheel 26 by the urging action of the pawl pushing spring 38 formed of a leaf spring. Can be engaged. At this time, the first and second poles 30A, 30B
Are fitted and held in holding portions 38A and 38B of the spring 38, respectively.

FIG. 7 shows a state in which the handle 3 is in the neutral position. At this time, the first and second poles 3
The claws 34A, 34B of the ratchet wheel 26A and the teeth 35A of the ratchet wheel 26 are both urged by the spring 38.
Is engaged. Moreover, the protrusions 37A, 37B of the pawls 30A, 30B are in pressure contact with the outer peripheral portion of the guide member adjacent to the cam 36 with the cam 36 interposed therebetween.

As described above, when the handle 3 is rotated in the first direction A, that is, clockwise in FIG. 7 to raise the seat cushion 1 shown in FIG. The pole support members 30A and 30B of
Revolves around the rotation axis X of the handle 3 in the first direction A. Therefore, the protrusion 37A of the first pole 30A moves away from the cam 36, and the first pole 30A
Of the ratchet wheel 26 remains engaged with the teeth 35 of the ratchet wheel 26. On the other hand, since the projection 37B of the second pole 30B rides on the cam 36, the second pole 30B swings clockwise in FIG. 7 around the swing axis Y2, and the second pole 30B The pawl portion 34B separates from the teeth 35 of the ratchet wheel 26, and the engagement between them is released.

The pawl portion 34A of the first pole 30A remains engaged with the teeth 35 of the ratchet wheel 26, and the first pole 30A revolves in the first direction A.
The pawl portion 34A rotates the ratchet wheel 26 in the first direction A, that is, the clockwise direction in FIG. 7, while strongly engaging the teeth 35 of the ratchet wheel 26. When the ratchet wheel 26 rotates in this manner, the handle shaft 21 fixed to the ratchet wheel 26 also has the same first position.
The rotation is transmitted to the pinion 6 via the brake device 9 in a manner described later, and the rotation causes the seat cushion 1 to rise as described above with reference to FIGS. 2 and 3. I do.

When the handle 3 is rotated in the first direction A by a predetermined angle smaller than 360 °, for example, 20 ° to 30 °, the first pole support member 31A is moved to one end 29A of the elongated hole 29. , Whereby further rotation of the handle 3 is prevented. Thus, the end portion 29A of the long hole 29
Serves as a stopper for the pole support member 31A.

Next, when the occupant releases his / her hand from the handle 3, the handle 3 is actuated by the action of a return spring described later.
Returns to the neutral position shown in FIG. 7 together with the first and second poles 30A and 30B and the first and second pole support members 31A and 31B. At this time, the claw portion 34B of the second pole 30B also The teeth 35 are engaged. Also during this return operation, the claw portion 34A of the first pawl 30A remains engaged with the teeth 35 of the ratchet wheel 26, but at the time of the movement, the claw portion 34A is connected to the ratchet wheel 26 as described later.
Ratchet wheel 26 slides against tooth 35 of
In the direction B, ie, the counterclockwise direction in FIG.

Each time the above-mentioned turning operation of the handle 3 is performed, the seat cushion 1 is raised by a predetermined amount,
By repeating such a rotation operation, the seat cushion 1 can be finally lifted to the uppermost position shown in FIG.

When the handle 3 is turned in the second direction B, that is, counterclockwise in FIG. 7 from the state where the handle 3 is in the neutral position shown in FIG. 7, the first pole 30A Since the protrusion 37A rides on the cam 36, the claw 34A is separated from the teeth 35 of the ratchet wheel 26, and the claw 34B of the second pole 30B meshes with the teeth 35 of the ratchet wheel 26, and the ratchet wheel 2
6 in the second direction B (counterclockwise direction in FIG. 7).
Then, the rotation is performed by the handle shaft 21 and the brake device 9.
To the pinion 6, whereby the seat cushion 1 is lowered by a predetermined amount. Also in this case, when the handle 3 is rotated by a predetermined angle smaller than 360 °, the second pole support member 31B is moved to the other end 29 of the elongated hole 29.
B, and further rotation of the handle 3 is prohibited. If the hand is released from the handle 3 in this state, the handle 3 returns to the neutral position shown in FIG. 7 also by the action of the return spring. By rotating the handle 3 again in the second direction B, the seat cushion 1 is lowered by a predetermined amount, and by repeating this operation, the seat cushion 1 can be lowered to the lowest position shown in FIG. it can.

As described above, the seat cushion 1 can be raised or lowered by rotating the handle 3 in the first or second direction by a predetermined angle smaller than 360 °. By repeating the operation, the seat cushion 1 can be brought to the highest position or the lowest position. The seat cushion 1 can be raised and lowered to the uppermost position or the lowermost position without turning the handle 3 by a large angle at a time, for example, 360 ° or more. Thereby, the seated person can easily perform the operation. In this way, the seated person
It is possible to adjust the seat cushion 1 to a height position desired by the user and sit on the seat in a comfortable posture.

As will be understood from the above description, the cam 36 causes the handle 3 in the neutral position to move in the first direction A.
The first and second pawls 30A, 3 that previously engaged the teeth 35 of the ratchet wheel 26
The second pole 30B of the claw portions 34A, 34B of 0B
The second pawl 30 so that the claw portion 34B of the second pawl is separated from the teeth 35 of the ratchet wheel 26 and disengaged therefrom.
B and swing the handle 3 in the neutral position to the second position.
The first and second pawls 3 that previously engaged the teeth 35 of the ratchet wheel 26 when rotated in the direction B
The teeth 34A of the first pole 30A of the teeth 34A, 34B of the teeth 0A, 30B are the teeth 3 of the ratchet wheel 26.
The first pawl 30A swings so as to be separated from the first pole 5 and released from the engagement.

FIG. 9 is an explanatory diagram showing an engagement state between the first pole 30A and the teeth 35 of the ratchet wheel 26.
The first pole 30A is the tooth 3 of the ratchet wheel 26.
7 is engaged in the first direction A from the position shown in FIG. 7, at this time, the claw portion 34A of the first pole 30A is fitted with the teeth 3 of the ratchet wheel 26.
5, a vertical force F is applied. For this reason, the claw portion 34 </ b> A strongly meshes with the teeth 35, and rotates the ratchet wheel 26 in the first direction A. Conversely, the first pole 3
When 0B revolves in the second direction B, the pole 30
The ratchet wheel 26A does not rotate in the second direction B nor in the first direction A because the pawl portion 34A of A slides against the teeth 35 of the ratchet wheel 26 as shown by the arrow C. 34A can return to the position shown in FIG. 7 while riding over the teeth 35 of the ratchet wheel 26. The relative position between the swing axis Y1 of the first pole 30A and the claw portion 34A of the first pole 30A that engages with the teeth 35 of the ratchet wheel 26 is set so that such an action can be obtained. .

Similarly, when the second pole 30B revolves in the second direction B from the position shown in FIG.
Exerts a vertical force on the teeth 35 of the ratchet wheel 26, causing the ratchet wheel 26 to rotate in a second direction, and conversely, the second pole 30B to move in the first direction A.
Revolves around the ratchet wheel 2
The sixth tooth 35 slides, and the ratchet wheel 26 stops without rotating.

As described above, when the first pole 30A revolves in the first direction A while the claw portion 34A of the first pole 30A is engaged with the teeth 35 of the ratchet wheel 26, the first The pawl 34A of the first pole 30A meshes with the teeth 35 of the ratchet wheel 26 to rotate the ratchet wheel 26 in the first direction A, and the pawls 34A of the first pole 30A engage the teeth 35 of the ratchet wheel 26.
When the first pole 30A revolves in a second direction B opposite to the first direction A in a state in which the teeth 35A of the ratchet wheel 26
In order to prevent the ratchet wheel 26 from rotating with respect to the swinging axis Y1 of the first pole 30A.
The relative position of the claw portion 34A of the first pole 30A engaging with the teeth 35 of the ratchet wheel 26 is set.
Similarly, when the second pole 30B revolves in the second direction B with the claw portion 34B of the second pole 30B engaged with the teeth 35 of the ratchet wheel 26, the claw of the second pole 30B The part 34B is the tooth 3 of the ratchet wheel 26
5, the ratchet wheel 26 is rotated in the second direction B, and the pawl portion 34B of the second pole 30B is engaged with the teeth 35 of the ratchet wheel 26, and the second pole 30B is When revolving in the direction A of 1,
The pawl portion 34B of the second pole 30B slides against the teeth 35 of the ratchet wheel 26, and the ratchet wheel 26
The relative position of the swing axis Y2 of the second pawl 30B and the claw portion 34B of the second pawl 30B that engages with the teeth 35 of the ratchet wheel 26 is set so as not to rotate the pawl 34B.

With such a configuration, the steering wheel 3 is rotated in the first direction A, so that the ratchet wheel 2 is rotated.
6 in the first direction A, and conversely, by rotating the handle 3 in the second direction B, the ratchet wheel 2 is rotated.
6 can be rotated in the second direction B.

FIG. 10 is a perspective view showing an example of the above-described return spring. The return spring 39 shown here is formed of a torsion coil spring (the return spring 39 is not shown in drawings other than FIG. 10). . When the handle 3 is in the neutral position shown in FIG. 7, each end 39A, 39B of the return spring 39 is formed on each side edge of the rising portion 23A (not shown in FIGS. 5 and 6) of the handle bracket 23. The notches 40A and 40B are pressed against each other, and the bent portions at the ends of the respective ends 39A and 39B are connected to one arm 27 of the guide member 27.
A is pressed against each side edge 41A, 41B.

When the handle 3 is rotated in the first direction A, the handle bracket 23 rotates in the first direction A together with the handle 3, but the guide member 27 remains stopped, so that one of the return springs 39 End 39A
Moves in the first direction A while engaging with one notch 40A of the handle bracket 23. On the other hand, the other end 39B of the return spring 39 is connected to the guide member 27.
Then, the notch 40B of the handle bracket 23 is separated from the other end 39B of the return spring 39 while being pressed against the side edge 41B. As a result, elastic energy is stored in the return spring 39.

Next, when the handle 3 is released, the handle bracket 23 receives a force from the first end 39A of the return spring 39 due to the elasticity of the return spring 39, and the handle bracket 23 is moved together with the handle 3 in the second direction. B, when the handle 3 reaches the neutral position shown in FIG. 7, the one end 39A of the return spring 39 is again connected to the one side edge 41 of the guide member 27.
Hit A. In this way, the handle 3 automatically returns to the neutral position, where it stops.

When the handle 3 at the neutral position is turned in the second direction B, the other end 39 B of the return spring 39 is turned in the second direction B, contrary to the above.
The guide bracket 27 moves in the second direction B while being engaged with the notch 40B of the handle bracket 23 that rotates in the direction of FIG. 3, and stops while one end 39A is pressed against one side edge 41A of the guide member 27. For this reason, if the user releases the handle 3 in this state, the handle bracket 23 returns to the return spring 39.
, And is automatically returned to the neutral position together with the handle 3.

FIG. 11 is a cross-sectional view of the brake device 9 shown in FIGS. Brake device 9 shown here
Are known per se as described in, for example, JP-A-62-258231. Therefore, only the outline of the configuration will be described below.

As can be seen from FIGS. 5, 6, and 11, the brake device 9 has a case 42 fixed to the lifter support 8, and the case 42 is formed in a cup shape with one end side opened. Have been. Also, this case 42
It has a concentric inner wall 42A and an outer wall 42B, and the inner wall 42A and the outer wall 42B are integrated via an annular end wall 42C opposite to the open end, and the inside of the inner wall 42A is hollow. It has become.

In the case 42, a core 43 having a substantially fan-shaped cross section is rotatably accommodated.
The handle shaft 21 penetrates the center of the handle shaft 21 and the handle shaft 21 and the core 43 are fixed to each other, and they can rotate integrally about the rotation axis X described above.

An annular groove 44 is formed in the core 43 about the rotation axis X.
A is fitted, and a small-diameter coil spring 45A is arranged inside the inner side wall 42A. Moreover, the large-diameter coil spring 45B is arranged between the outer peripheral surface of the core 43 and the inner peripheral surface of the outer wall 42B of the case 42.

Further, a stopper plate 46 is rotatably accommodated in the case 42, and the stopper plate 46
An annular groove 47 is formed around the rotation axis X, and an inner wall 42A of the case 42 and a small-diameter coil spring 45A are arranged in the annular groove 47. The handle shaft 21 is rotatably fitted in a through hole 48 (FIG. 5) of the stopper plate 46, and the pinion 6 is fixed to the stopper plate 46.

One end 49A of the large diameter coil spring 45B
Can be engaged with one circumferential end wall surface 50A of the core 43, and the other end 49B of the spring 45B is locked in a hole 51A formed in the stopper plate 46. One end 52A of the small-diameter coil spring 45A is engageable with the other circumferential end wall surface 50B of the core 43.
The other end 52B of A is locked in a hole 51B formed in the stopper plate 46.

As can be seen from the above description, the handle shaft 21 is rotatably supported on the lifter support 8 via the core 43, the stopper plate 46 and the case 42, and the pinion 6 is also connected to the stopper plate 46. It is rotatably supported by the lifter support 8 via the case 42 and is located concentrically with the handle shaft 21.

Here, the ratchet wheel 26 and the handle shaft 21 are rotated in the first direction A by rotating the handle 3 in the first direction A as described above.
The core 43 in the case 42 also rotates in the same first direction A. Thereby, the other circumferential end wall surface 50B of the core 43
Presses one end 52A of the small-diameter coil spring 45A,
As a result, the diameter of the small-diameter coil spring 45A is reduced, and the pressure contact force between the small-diameter coil spring 45A and the inner wall 42A of the case 42 is reduced. Thus, the core 43 can rotate in the first direction A together with the stopper plate 46, and accordingly, the pinion 6 rotates in the first direction A.

By rotating the handle 3 in the second direction B, even when the core 43 rotates in the same second direction, one of the circumferential end wall surfaces 50A of the core 43 has a large diameter coil spring. It engages with one end 49A of 45B and presses it. As a result, the diameter of the large-diameter coil spring 45B is reduced, and the coil spring 45B and the outer wall 42 of the case 42 are reduced.
The core 43 rotates together with the stopper plate 46 and the pinion 6 in the second direction B because the pressure contact force with B decreases.

On the other hand, when a large load is applied to the seat cushion 1 when the seat cushion 1 is at the highest position, for example, when a seated person sits on the seat cushion 1 as shown in FIG. A rotational force in a direction in which the rack 11 rotates clockwise in FIG. For this reason,
A rotational force is applied to the pinion 6 and the stopper plate 46 via the rack 11 such that the pinion 6 and the stopper plate 46 rotate in the counterclockwise direction (second direction B) in FIG. However, at this time, since one end 49B of the large-diameter coil spring 45B is engaged with the hole 51A of the stopper plate 46, the diameter of the large-diameter coil spring 45B is enlarged, and the coil spring 45B is enlarged.
A large frictional force acts between B and the outer wall 45B of the case 42. For this reason, the pinion 6 is extremely slightly
Although it may rotate in the direction B, it does not rotate significantly. Thereby, the seat cushion 1
Even if a large load is applied, this does not drop.

The pinion 6 and the stopper plate 46
On the other hand, when a rotational force is applied in a direction in which they rotate clockwise (first direction A) in FIG.
Since the other end 52B of the small-diameter coil spring 45A is locked in the hole 51B of the stopper plate 46, the small-diameter coil spring 45A increases in diameter, and the coil spring 45A
A large frictional force acts between the inner wall 42A of the case 42 and the inner wall 42A. For this reason, the pinion 6 and the stopper plate 46
Are prevented from rotating too much, if at all, in the first direction A.

As described above, the brake device 9 allows the rotation of the handle shaft 21 to be transmitted to the rotating body composed of the pinion 6, but the rotating body is provided with a rotating member other than the handle shaft 21, that is, on the side of the seat cushion 1. This constitutes an example of a brake means for prohibiting the rotating body from rotating when a rotational force is applied from. By providing such a braking means, even if an external force is applied to the seat cushion 1 after adjusting the height of the seat cushion 1, the seat cushion can be prevented from lowering or rising.

Various types of brake means other than the illustrated brake device 9 may be employed.

When the overall height of the above-described transmission mechanism of the seat lifter increases, the vertical width of the lifter support 8 that supports the transmission mechanism also increases, and the entire seat lifter increases in size, increasing its weight and cost. . Therefore, the diameter of the ratchet wheel 26 and the distance from the rotation axis X to the cam 36 are set small, and the first and second
It is conceivable to reduce the height of the entire transmission mechanism by reducing the size of the poles 30A and 30B. However, when the dimensions of these elements are set small as described above, the function of each element is impaired or the function is reduced.
Reducing the overall height of the transmission is inappropriate. For example, if the distance from the rotation axis X to the cam 36 is too small, the pawls 30A and 30B may not be able to reliably swing. As described above, there is a limit in reducing the size of each element of the transmission mechanism.

Therefore, in the sheet lifter of this embodiment,
As shown in FIG. 7, the distance from the rotation axis X of the handle 3 to the swing centers Y1, Y2 of the first and second pawls 30A, 30B is L1, and the cam 36 comes into contact with the rotation axis X of the handle 3. When the distance to the cam contact portion of the first and second pawls 30A, 30B (the contact portion where the protrusions 37A, 37B of each of the pawls 30A, 30B come into contact with the cam 36 in the example of the drawing) is L2, The respective distances L1 and L2 are set such that L1 <L2.

As described above, if the distance L2 is too small, the original function of the cam 36 is impaired, so that it cannot be reduced too much. On the other hand, the rotation axis X
, The distance L1 from the swing centers Y1 and Y2 of the poles 30A and 30B is set smaller than the distance L2.
The function of swingably supporting the pawls 30A and 30B does not decrease. From this viewpoint, in the sheet lifter of this example, the distances L1 and L2 satisfy L1 <L2.
L2 is set so that the height of each of the pawls 30A and 30B can be reduced, whereby the overall height of the transmission mechanism can be kept small.
It is possible to reduce the width in the height direction. In this way, it is possible to reduce the weight and cost of the seat lifter while preventing the function of each element from deteriorating.

Further, the seat lifter of the present embodiment has a handle 3
A guide member 27 having an arc-shaped elongated hole 29 formed around the rotation axis X is slidably fitted in the elongated hole 29, and the first and second pawls 30A and 30B are connected to the guide member 27. Pole support members 31A and 31B are supported so as to be swingable, and each end 29A and 29B of the elongated hole 29 is configured to serve as a stopper for the pole support members 31A and 31B. The elongated hole 29 of the guide member 27
Thus, the first and second pawls 30A, 30B can be revolved around the rotation axis X while correctly guiding them, and the respective ends 29A, 29B of the elongated hole 29 stop the respective pawls 30A, 30B. The first and second poles 30A, 30A
There is no need to separately provide a guide member for guiding the OB and a stopper for stopping the guide member, and the number of parts of the seat lifter can be reduced.

In the illustrated example, the first and second pole supporting members 31A and 31B are provided, and the first and second poles 30A and 30B are supported on each of them in a swingable manner. A support member may be provided, and the first and second pawls 30A and 30B may be supported by one of the pole support members so as to be swingable.

Further, in the seat lifter of this embodiment, the pawls 34A, 34B of the first and second pawls 30A, 30B are securely engaged with the teeth 35 of the ratchet wheel 26, respectively. A spring 38 is provided as an example of an urging means for urging the ratchet wheel 26 toward the teeth 35 of the ratchet wheel 26, whereby the ratchet wheel 26 is correctly rotated by the revolution of the first and second pawls 30A and 30B. Can be rotated. In addition, the spring 38 in the illustrated example includes the first and second pawls 30A,
1 provided with holding portions 38A and 38B for holding both
Since it is composed of two leaf springs, the structure of the spring 38 can be simplified.

The present invention is not limited to a seat lifter that raises and lowers a seat cushion of a seat provided in a vehicle cabin, and can be widely applied to a seat lifter for a seat cushion of other various seats.

[0062]

According to the first aspect of the present invention, the vertical position of the seat cushion can be adjusted by rotating the handle, and the pivot axis of the first and second pawls can be adjusted from the rotation axis of the handle. Is set smaller than the distance from the rotation axis to the cam contact portions of the first and second pawls that contact the cam, thereby reducing the size of the seat lifter without impairing the function of each element of the seat lifter. And the weight and cost can be reduced.

According to the second aspect of the present invention, there is no need to separately provide a guide member for guiding the revolving first and second pawls and a stopper for stopping the respective pawls.
The number of parts of the seat lifter can be reduced.

[Brief description of the drawings]

FIG. 1 is a side view of a seat.

FIG. 2 is a diagram showing a state of a transmission means when a seat cushion is at an intermediate height position.

FIG. 3 is a diagram showing a state of a transmission means when a seat cushion is at an uppermost position.

FIG. 4 is a diagram showing a state of the transmission means when the seat cushion is at the lowest position.

FIG. 5 is a cross-sectional view of a handle and a transmission mechanism for transmitting rotation of the handle to a pinion.

FIG. 6 is an exploded cross-sectional view showing the elements shown in FIG. 5 separately.

FIG. 7 is a diagram illustrating a positional relationship between a handle and first and second poles.

FIG. 8 is a diagram showing some elements of the transmission mechanism.

FIG. 9 is a view for explaining an engagement state between pawl portions of a pole and teeth of a ratchet wheel.

FIG. 10 is a perspective view showing a return spring.

FIG. 11 is a cross-sectional view of the brake device.

[Explanation of symbols]

 3 Handle 8 Lifter Support 21 Handle Shaft 26 Ratchet Wheel 29 Slot 29A End 29B End 30A First Pole 30B Second Pole 31A Pole Support Member 31B Pole Support Member 34A Claw 34B Claw 35 Tooth 36 Cam A First direction B Second direction X Rotation axis Y1 Swing shaft Y2 Swing shaft

Continuation of the front page (72) The inventor Osamu Nagano 2 Kirihara-cho, Fujisawa-shi, Kanagawa Prefecture Shiroki Industry Co., Ltd. F term (reference) 3B087 BA15 BB21 BC27

Claims (2)

[Claims] 1. A handle shaft rotatably supported by a lifter support, a handle supported by the handle shaft so as to be rotatable relative to the handle shaft, and a rotation axis thereof when the handle is rotated. First and second pawls revolving around and swinging about their own swing axis, a ratchet wheel fixed to the handle shaft concentrically with the handle shaft, and the handle shaft The concentrically arranged rotator and the rotation of the handle shaft are allowed to be transmitted to the rotator, but when a rotational force is applied to the rotator other than the handle shaft, the rotator rotates. Prohibiting brake means, and a transmission means for converting the rotation of the rotating body into a lifting / lowering operation of a seat cushion, wherein each claw portion of the first and second pawls is provided with respect to the teeth of the ratchet wheel, The first pole can be engaged with the ratchet wheel at different positions in the circumferential direction, and the first pole can be moved in the first direction in a state where the pawl portion of the first pole is engaged with the teeth of the ratchet wheel. When revolving, the pawls of the first pole mesh with the teeth of the ratchet wheel to rotate the ratchet wheel in the first direction, and the pawls of the first pole engage the teeth of the ratchet wheel. When the first pole revolves in the second direction opposite to the first direction, the pawl of the first pole does not slide on the teeth of the ratchet wheel to rotate the ratchet wheel. In this way, the relative position between the pivot axis of the first pole and the pawl portion of the first pole that engages with the teeth of the ratchet wheel is set, and the pawl portion of the second pole engages with the teeth of the ratchet wheel. Combined When the second pole revolves in the second direction, the pawl of the second pole meshes with the teeth of the ratchet wheel to rotate the ratchet wheel in the second direction, and When the second pawl revolves in the first direction with the pawl of the pawl engaged with the teeth of the ratchet wheel,
The second pole engages the pivot axis of the second pole and the teeth of the ratchet wheel so that the pawl of the second pole does not slide against the teeth of the ratchet wheel to rotate the ratchet wheel. When the relative position of the pawl portion of the pawl is set and the handle in the neutral position is rotated in the first direction, the first and second pawls that have been engaged with the teeth of the ratchet wheel up to that time are rotated. Swinging the second pawl so that the pawl of the second pawl of the pawl is separated from the teeth of the ratchet wheel and disengaged therefrom,
And when the handle in the neutral position is rotated in the second direction, the first pole of the first and second pawls of the first and second pawls that have been engaged with the teeth of the ratchet wheel up to that time. A cam for swinging the first pawl such that the pawl is separated from the teeth of the ratchet wheel and disengaged from the teeth, and a swing axis of the first and second pawls from a rotation axis of the handle; L1 and the first and second abutments on the cam from the rotation axis of the handle.
When the distance between the pole and the cam contact portion is L2, L
A sheet lifter wherein the distances L1 and L2 are set such that 1 <L2. 2. A guide member having an arc-shaped elongated hole formed around a rotation axis of the handle, and slidably fitted in the elongated hole, and the first and second pawls. The pole lifter according to claim 1, further comprising: a pole support member for swingably supporting the pole support member, and each end of the elongated hole serves as a stopper for the pole support member.