JP2001197954A - Seat lifter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a seat lifter which can quickly and surely regulate the motion of a seat when a load is applied to the seat without a handle operation. SOLUTION: This seat lifter is equipped with a handle, a first rotating body, a second rotating body, a small diameter annular wall and a large diameter annular wall, and a small diameter coil spring and a large diameter coil spring. In this case, the handle can be rotate- operated between a neutral location and normal and reverse moving ends. To the first rotating body, rotations in the normal direction and the opposite direction are applied by a reciprocating motion of the handle from the neutral location. The second rotating body is coaxial with the first rotating body, and rotates while interlocking with a vertically moving motion of the seat. The small diameter annular wall and the large diameter annular wall are concentric with the first and second rotating bodies. The small diameter coil spring and the large diameter coil spring are engaged with the inner peripheral surfaces of the small diameter annular wall and the large diameter annular wall under a free state, and at least the cross sections of the engaged sections are formed into a square shape. When a load is applied to the seat cushion, the vertically moving motion of the seat cushion is regulated by regulating the rotation of the second rotating body. Also, when the first rotating body is rotated through the handle, the diameter of the small diameter or large diameter coil spring contracts, and the rotation of the second rotating body is allowed, and the seat is vertically moved by this seat lifter.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seat lifter that raises and lowers a seat by operating a handle.

[0002]

2. Description of the Related Art Some seats for vehicles such as automobiles and railway cars, for theaters, and for various other purposes are provided with a seat lifter for adjusting the height of a seat cushion of the seat. This type of seat lifter often rotates the handle to raise and lower the seat cushion to the height desired by the occupant, but when the handle is operated, the seat is raised and lowered, and the handle is not operated. Sometimes, a brake mechanism is provided for holding the seat cushion so that its height does not change even when a load is applied. There is a type of brake mechanism in which the diameter of a coil spring is increased when a load is applied to a seat cushion so that the coil spring is pressed against an inner wall (annular wall) of a drum shape. The braking performance is determined by the response of the vehicle and its pressing force.

[0003] In a seat lifter of the type in which the seat is lifted and lowered by sufficiently reducing the rotation of the handle by a reduction mechanism, the amount of lift of the seat per unit rotation of the handle is small, so that the brake mechanism is applied after a load is applied to the seat cushion. Even if there is a slight delay until the coil spring comes into pressure contact with the annular wall and the brake starts working, the movement amount of the seat cushion can be small. However, in the case of a type of seat lifter that does not have such a speed reduction mechanism or has a small reduction ratio with respect to the operation of the steering wheel, the amount of movement of the seat cushion when the brake operation is delayed increases, so that a brake that operates quickly and reliably is provided. Is required.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and is capable of quickly and reliably regulating the operation of a seat when a load is applied to the seat without operating a steering wheel. The purpose is to obtain.

[0005]

SUMMARY OF THE INVENTION A seat lifter according to the present invention has a neutral position and a handle that can be rotated between a neutral position and a forward / reverse moving end; reciprocating operation between the neutral position and a forward moving end And a first rotating body that is provided with rotation in the forward and reverse directions by a reciprocating operation between the neutral position and the backward moving end; coaxial with the first rotating body and interlocked with the lifting / lowering operation of the sheet A second rotating body that rotates; a small-diameter annular wall and a large-diameter annular wall provided concentrically with the first and second rotating bodies; one end is locked by the second rotating body, and the other end is the first rotating body. A small-diameter coil spring which can be engaged with and disengaged from one of a pair of radial wall surfaces of the rotating body and whose outer edge is engaged with the inner peripheral surface of the small-diameter annular wall in a free state; and one end of which is engaged with the second rotating body. And the other end is detachable from the other one of the pair of radial walls of the first rotating body, A large-diameter coil spring whose portion engages with the inner peripheral surface of the large-diameter annular wall; the small-diameter coil spring and the large-diameter coil spring each include at least a winding portion of a laminated spring that comes into contact with the small-diameter annular wall and the large-diameter annular wall. Is formed in a rectangular shape, and when a load is applied to the seat in a state where the handle is not operated, the small- or large-diameter coil spring is expanded by the rotational force acting on the second rotating body. The outer edge of the small-diameter or large-diameter coil spring having a diameter and a rectangular cross-sectional shape presses against the inner peripheral surface of the small-diameter annular wall or the large-diameter annular wall to regulate the rotation of the second rotating body and raise and lower the seat. When the first rotating body is rotated in the normal or reverse direction via the handle, the end of the small-diameter or large-diameter coil spring is pressed by the radial wall surface of the first rotating body, thereby restricting the operation. Or a large diameter coil There is allowed rotation of the second rotary member decreases in diameter seat is characterized in that it is lifting.

As described above, in a seat lifter of the type in which the seat is raised and lowered by reciprocating in the normal and reverse directions from the neutral position of the handle, the number of times the handle is operated may deteriorate the operability. It is difficult to provide a speed reduction mechanism. Therefore, as described above, a quick and powerful brake is required, but according to the above configuration,
When a load is applied to the seat cushion without operating the steering wheel, the coil spring having a rectangular cross section is quickly and reliably pressed against the annular wall to obtain a strong braking force, so that the movement of the seat can be suppressed.

[0007] The seat lifter of the present invention also has a neutral position, a handle operable to rotate between the neutral position and forward and reverse moving ends; a first rotating body rotatable about a rotation axis of the handle; A second rotating body which is coaxial with the first rotating body and is rotatably supported relative to the first rotating body and has a pair of radial walls opposed to each other in a circumferential direction;
A lift mechanism for converting the rotation of the rotator into a lifting / lowering operation of the seat; provided between the handle and the first rotator, wherein the rotation of the handle from the neutral position to the forward / reverse moving end is performed by the first rotator. A ratchet mechanism that transmits the rotation from the forward / reverse moving end of the handle to the neutral position to the first rotating body;
A small-diameter annular wall and a large-diameter annular wall provided concentrically with the first and second rotating bodies; one end is locked to the second rotating body, and the other end is a pair of radial walls of the first rotating body. A small-diameter coil spring whose outer edge is engaged with the inner peripheral surface of the small-diameter annular wall in a free state; and one end of which is locked to the second rotating body and the other end of which is connected to the second rotating body. A large-diameter coil spring which is detachable from the other of the pair of radial walls of the rotating body and whose outer edge is engaged with the inner peripheral surface of the large-diameter annular wall in a free state; Each of the springs has at least a rectangular cross-section in the winding section of the laminated spring in contact with the small-diameter annular wall and the large-diameter annular wall, and a load is applied to the seat when the handle is not operated. The small or large diameter coil due to the rotational force acting on the second rotating body. The outer diameter of the coil spring having a small diameter or a large diameter and having a rectangular cross-sectional shape is pressed against the inner peripheral surface of the small-diameter annular wall or the large-diameter annular wall to regulate the rotation of the second rotating body. When the first rotating body is rotated in the forward or reverse direction via the handle, the end of the small or large diameter coil spring is pressed by the radial wall surface of the first rotating body. The small or large diameter coil spring is reduced in diameter to permit rotation of the second rotator, and the second rotator is rotated together with the first rotator to raise and lower the sheet via the lift mechanism. It is characterized by:

The ratchet mechanism of the seat lifter includes a handle shaft fixed to the first rotating body and rotatably supported with respect to the handle; a ratchet wheel fixed to the handle shaft; A first and a second pole that perform a revolving operation about the handle shaft and swing about the revolving locus; formed on the first and second poles, a ratchet on an outer peripheral portion of the ratchet wheel; A claw portion meshing with the teeth; a claw portion formed on the first pole transmits the moving force to the ratchet teeth when the first pole revolves in the forward direction to rotate the ratchet wheel, and rotates the ratchet wheel in the reverse direction. The ratchet teeth do not transmit their movement when revolving around;
The pawl formed on the second pole does not transmit the moving force to the ratchet teeth when the second pole revolves in the forward direction, and transmits the moving force to the ratchet teeth when revolving in the reverse direction. To rotate the ratchet wheel; a pawl urging means for urging the first and second pawls to a swinging position where the claw meshes with the ratchet teeth; and the handle is rotated forward and backward. At this time, of the first and second poles that revolve with the rotation of the handle, the other pole that does not transmit the moving force to the ratchet wheel is moved to the position where the engagement between the pawl portion and the ratchet teeth is released. It is preferable to provide a pole retracting mechanism that swings up to a maximum.

[0009] The seat lifter of the present invention also has a neutral position and a handle that can be rotated between the neutral position and a forward / reverse moving end; a first rotating body that can rotate about a rotation axis of the handle; A second rotating body which is coaxial with the first rotating body and is rotatably supported relative to the first rotating body and has a pair of radial walls opposed to each other in a circumferential direction;
A lift mechanism for converting the rotation of the rotator into a lifting / lowering operation of the seat; provided between the handle and the first rotator; when the handle is not operated, the mechanical connection between the handle and the first rotator is established. The handle is mechanically connected to the first rotating body when the handle is rotated from the neutral position to the forward moving end side and the opposite moving end side from the neutral position, and the first rotating body is moved in the forward direction. A small-diameter annular wall and a large-diameter annular wall provided concentrically with the first and second rotating bodies; one end is locked to the second rotating body, and the other end is A small-diameter coil spring that is detachable from one of a pair of radial walls of the first rotating body and whose outer edge is engaged with the inner peripheral surface of the small-diameter annular wall in a free state; The other end of the first rotator can be engaged with and disengaged from the other of the pair of radial walls. A large-diameter coil spring whose outer edge engages the inner peripheral surface of the large-diameter annular wall in a free state; the small-diameter coil spring and the large-diameter coil spring are respectively laminated at least in contact with the small-diameter annular wall and the large-diameter annular wall; The winding portion of the spring has a rectangular cross section; when a load is applied to the seat in a state where the handle is not operated, a small diameter or a large diameter is generated by a rotational force acting on the second rotating body. And the outer edge of the small or large diameter coil spring having a rectangular cross-sectional shape presses against the inner peripheral surface of the small or large annular wall to restrict the rotation of the second rotating body. When the first rotating body is rotated in the forward or reverse direction via the handle, the end of the small- or large-diameter coil spring is restricted by the radial wall surface of the first rotating body. Pressed and said small Or large diameter coil spring allowing rotation of the second rotary member reduced in diameter,
The second rotating body is rotated together with the first rotating body, and the sheet is moved up and down via a lift mechanism.
According to the seat lifter of this aspect, when the handle is not operated, a strong brake mechanism is required because the mechanical connection between the handle and the lift mechanism is released, but the cross-sectional shape of the coil spring for braking is square. Therefore, when a load acts on the seat cushion, the coil spring can quickly expand in diameter and compress on the annular wall to obtain a strong braking force.

The handle interlocking control mechanism is a handle shaft having a coaxial ratchet wheel fixed to the first rotating body; provided rotatably with respect to the handle shaft, and connecting the handle shaft to the operation input unit. A base plate on which a handle is pivotally mounted at an intermediate portion; a long hole formed on the handle, in which a handle shaft is movable and rotatably fitted in a hole forming direction; First and second pawls rotatably mounted on one end and capable of meshing with the teeth of a ratchet wheel, and the other end on the other end side with which a handle can abut; And urging means for urging the teeth of the second pole away from the ratchet wheel. When the handle is not operated, the urging means causes the first and second poles to be moved. Teeth are interlocked handle and the handle shaft without teeth mesh with the ratchet wheel is blocked in,
When the handle is rotated, the handle rotates with respect to the base plate until the handle shaft comes into contact with the end of the long hole, and the first or second pole is pressed by the handle so that its teeth are in contact with the ratchet wheel. After the handle shaft is brought into contact with the end of the elongated hole, the handle rotates together with the base plate about the handle shaft, and the rotation of the handle causes the first or second pole meshed with the ratchet wheel to rotate. It is preferable that the handle shaft is rotated by being transmitted to the ratchet wheel via the ratchet wheel.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A seat lifter according to an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a side view showing an outline of a seat arranged in a cabin of an automobile. This seat has a seat cushion 1 that supports the buttocks of the occupant and a seat pack 2 that supports the back of the occupant. By rotating the handle 3, the height of the handle 3 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).

FIGS. 2 to 4 show an example of a pinion 6 which is driven to rotate by the rotation of the handle 3 shown in FIG. , A lifter support 8, in which illustration of a handle 3 and a transmission groove for transmitting rotation of the handle 3 to a pinion 6, which will be described later, are omitted. Further, most of the lift mechanism 7 shown in FIGS. 2 to 4, the lifter support 8, the pinion 6, and the handle 3
The transmission mechanism for transmitting the rotation of the pinion to the pinion 6 is covered by a cover not shown in these figures, and
It is exposed to the outside of the cover as shown in FIG.

Lifter support 8 shown in FIGS. 2 to 4
Is made of a rigid body such as a metal plate or a hard resin aret,
The lifter support 8 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. 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. For example, 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 and 13 rotate counterclockwise about their respective base ends, and as shown in FIG.
The lifter support 8 connected to the members 2 and 13, that is, the entire seat cushion 1 is raised.

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. When the pinion 6 is rotated in the counterclockwise direction shown in FIG. 2, the pinion 6 shown in FIG.
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 sheet cushion 1 (the direction perpendicular to the plane of FIG. 1 to FIG. 4). A lifter support, a rotating body that rotates similarly to the rack 11,
A first and a second support link, and a connection link having each end pivotally attached to the second support link and the rotating body are provided. The rack 11 is fixed to one end of a support shaft 10, and the support shaft 10 is rotatably supported by the lifter support 8 and the lifter support on the other side and extends long in the width direction of the seat cushion 1. The above-mentioned rotating body is fixed to the other end of the shaft 10. Accordingly, 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 connected to the rack 11 shown in FIGS. The same operation as the connecting link 20 and the first and second links 12 and 13 is performed, so that the seat cushion 1 can be raised or lowered in a stable state.

As is apparent from the above description, the first and second support links, racks, rotating bodies, support shafts, and connection links are provided by the lift mechanism 7 that converts the rotation of the pinion 6 into the elevating operation of the seat cushion 1. An example is configured.

It should be noted that a lift mechanism other than the illustrated form may be appropriately employed. In the seat lifter shown in FIGS. 2 to 4, the seat cushion 1 is raised and lowered by the rotation of the pinion 6. It can also be configured to convert to

FIG. 5 shows an example of the handle 3, a transmission mechanism for transmitting the rotation of the handle 3 to the pinion 6, and a brake mechanism 9 for holding the seat cushion at a predetermined height when the handle 3 is not operated. FIG. 6 is an exploded sectional view thereof. The transmission mechanism from the handle 3 to the pinion 6 is such that the rotation of the handle 3 from the neutral position to the forward / reverse moving end is performed by the handle shaft 21, that is, the pinion 6.
The rotation includes a ratchet mechanism that does not transmit the rotation to the neutral position from the forward and reverse movement ends of the handle 3 to the handle shaft 21. FIG. 7 is a view of the transmission mechanism including the ratchet mechanism viewed from the right side of FIG. 5, in which some elements are omitted, and the handle 3 is represented by a chain line. It is a figure which shows each of some elements of the transmission mechanism containing the said ratchet mechanism. Hereinafter, first, a transmission mechanism for transmitting the rotation of the handle 3 to the pinion 6 will be described, and then the brake mechanism 9 will be described.

As shown in FIGS. 5 and 6, the seat lifter has a handle shaft 21. It is rotatably supported by the support 8. 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,
The center hole 25 of the handle bracket 23 is
1 is rotatably fitted. Thus, handle 3
Are supported by the handle shaft 21 via a handle joint bracket 22 and a handle bracket 23 so as to be rotatable relative to the handle shaft 21. Note that the handle joint bracket 22 and the handle bracket 23 may be omitted, and the handle 3 may be directly rotatably supported on the handle shaft 21. The handle 3 and the handle shaft 21
It rotates about 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 shown in FIGS. They are arranged concentrically.
Further, the above-described brake mechanism 9 allows the rotation of the handle shaft 21 to be transmitted to the rotating body (the second rotating body) including the pinion 6, but a rotational force is applied to the rotating body from other than the handle shaft. At this time, the rotating body serves to inhibit rotation of the rotating body, and a specific configuration thereof will be described in detail later.

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 illustrated. And is fixed to the lifter support 8 with no screw, and the center hole 28 of the guide member 27 is fixed.
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 the present embodiment are constituted by pins, each of which is provided with a hole 32 formed in the handle bracket 23 as shown in FIGS.
A, 32B (FIG. 8) and are fixed here.
The holes 33A, 33B (FIG. 8) formed in the first and second poles 30A, 30B are rotatably fitted to the first and second pole support members 31A, 31B. . Thus, each pole 30A, 30B
Are swingably supported by the pole support members 31A and 31B, and swing axes Y1 and Y2 serving as swing centers at this time.
Is the central axis of each pole support member 31A, 31B.

As described above, the first and second pole support 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 either case, as shown in FIG. 7, the first and second pawls 30A and 30B are 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. The first and second pawls 30 </ b> A, 30 </ b> B revolve around the rotation axis X, which is the center of the rotation, when the handle 3 rotates. Moreover, the first and second poles 30A, 3A
0B can be pivoted about their own pivot axes Y1 and Y2 through other elements or directly through the handle 3.
It is supported by.

As shown in FIG. 7, the claws 34A and 34B of the first and second pawls 30A and 30B are different from the teeth 35 on the surface of the ratchet wheel 26 in the circumferential direction of the ratchet wheel 26. Can be engaged at different positions.

As shown in FIGS. 7 and 8, a cam 36 is formed on the outer peripheral portion of the guide partition member 27, and this cam 36 has a part of the outer peripheral portion of the guide member adjacent thereto. It is formed by swelling in the radial direction from the outer periphery of the guide 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 periphery of the guide member 27 including the cam 36. Further, the first and second pawls 30A and 30B are springs (pole biasing means) 38 for pushing the poles made of leaf springs.
Of the pawls 3 of the pawls 30A, 30B
4A and 34B can reliably engage the teeth 35 of the ratchet wheel 26. At this time, the first and second pawls 30A, 30B are connected to the holding portions 38A, 38B of the spring 38.
Are fitted and held 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 pawl portions 34A, 34B of the ratchet wheel 26A and the tooth portions 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.

Here, as described above, in order to raise the seat cushion 1 shown in FIG.
7, that is, in the clockwise direction in FIG. 7, the first and second pole support members 30A and 30B
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. That is, the pawl 30B is retracted from the meshing position with the ratchet wheel 26.

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
The rotation is transmitted to the pinion 6 via the brake mechanism 9 in a manner to be 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 29 of the elongated hole 29
A 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 moved by the action of a return spring (neutral holding mechanism), which will be described later, to the first and second poles 30A, 30A.
0B and first and second pole supporting members 31A, 31B
At the same time, it returns to the neutral position shown in FIG.
The pawl portion 34B of the pole 30B also engages with the teeth 35. Also during this return operation, the pawl portion 34A of the first pawl 30A remains engaged with the teeth 35 of the ratchet wheel 26, but at this time, the pawl portions 34A The ratchet wheel 26 does not rotate in the second direction B, ie, the counterclockwise direction in FIG.

Each time the above-described turning operation (reciprocating operation) of the handle 3 to one of the moving ends is performed, the seat cushion 1
The seat cushion 1 can be lifted up by a predetermined amount, and 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 separates 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 mechanism 9.
To the pinion 6, and 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 user releases the handle 3 while the handle 3 is at the moving end, 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 handle 3 is rotated in the first or second direction by a predetermined angle smaller than 360 °, that is, the handle 3 is reciprocated from the neutral position to the forward / backward moving end. By moving the seat cushion 1, the forward / reverse seat cushion 1 can be raised or lowered, and the seat cushion 1 can be brought to the uppermost or lowermost position by repeating the rotation operation. Without rotating the handle 3 by a large angle at a time, for example 360 ° or more, the seat cushion 1
Can be raised or lowered to the highest or lowest position. Thereby, the seated person can easily perform the operation. In this way, the occupant can adjust the seat cushion 1 to a desired height position 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.
One revolution, the ratchet wheel 26
The first and second pawls 30A engaged with the teeth 35 of the
The second pole 30 of the claw portions 34A, 34B of the 30B
B so that the claw portion 34B of B is separated from the teeth 35 of the ratchet wheel 26 to release the engagement.
It has the function of swinging OB. Further, when the handle 3 in the neutral position is rotated in the second direction B, the cam 36 engages with the pawls of the first and second pawls 30A and 30B which have been engaged with the teeth 35 of the ratchet wheel 26 until then. Part 34
The pawl portion 34A of the first pole 30A out of the A and 34B has a function of swinging the first pole 30A so as to separate from the teeth 35 of the ratchet wheel 26 and release the engagement. That is, a pole retreat mechanism is configured to retreat one of the pawls 30A and 30B from the meshing position with the ratchet wheel 26 when the handle 3 is rotated in the forward and reverse directions from the neutral position.

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.
Considering the case where the lug revolves in the first direction A from the position shown in FIG. 7 in the state of being engaged with the gear 5, the claw portion 34A of the first pole 30A
5, a vertical force F is applied. Therefore, 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 pawl 30A and the claw portion 34A of the first pawl 30A engaging with the teeth 35 of the ratchet wheel 26 is set so that such an effect 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 with the pawl portion 34A of the first pole 30A engaged with the teeth 35 of the ratchet wheel 26, the first The pawl portion 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 pawl portion 34A of the first pole 30A engages the teeth 35 of the ratchet wheel 26.
When the first pawl 30A revolves in a second direction B opposite to the first direction A in a state where the first pawl 30A is engaged with the pawl portion 34A of the ratchet wheel 26,
In order to prevent the ratchet wheel 26 from rotating with respect to the rotation axis Y1 of the first pole 30A.
The relative position of the claw portion 34A of the first pole 30A that engages 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 that the second pawl 30B is not rotated.

With such a configuration, by rotating the handle 3 in the first direction A, the ratchet wheel 2
6 in the first direction A, and conversely, by rotating the handle 3 in the second direction B, the ratchet wheel 2
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 constituted by a torsion coil spring (torsion spring).
9 is not shown. When the handle 3 is in the neutral position shown in FIG.
A and 39B are the rising portions 23A of the handle bracket 23.
(Not shown in FIG. 5 and FIG. 6) are respectively pressed against notches 40A and 40B formed on the respective side edges, and the bent portions at the tips of the ends 39A and 39B are formed in the guide member 2
7 is in pressure contact with each side edge 41A, 41B of one arm 27A.

When the handle 3 is rotated in the first direction A, the handle bracket 23 rotates together with the handle 3 in the first direction A, but the guide member 27 remains stopped. No Hata 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 hand is released from the handle 3, 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, one end 39 A of the return spring 39 is connected to 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
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.

In the seat lifter of the present embodiment, as shown in FIG.
The first and second pawls 30 </ b> A and 30 abutting on the cam 36 from the rotation axis X of the handle 3 are set to L <b> 1.
B cam contact portion (in the example of the figure, each pole 30A, 30B
L2 is the distance between the protrusions 37A and 37B of the cam contact 36).
The respective distances L1 and L2 are set.

Generally, when the total height in the vertical direction of the transmission mechanism from the handle 3 to the pinion 6 increases, the vertical width of the lifter support 8 that supports the transmission mechanism also increases, and the entire seat lifter increases in size and weight and cost. Increase. In order to solve this, the diameter of the ratchet wheel 26 and the distance from the rotation axis X to the cam 36 are set to be small, and the first and second pawls 30A and 30B are miniaturized. It is conceivable to reduce the height. However, if the dimensions of these elements are set small, the function of each element is impaired or the function is reduced.Therefore, simply setting the dimensions small to reduce the overall height of the transmission mechanism is not possible. Improper. 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.
On the other hand, the distance L1 from the rotation axis X to the swing centers Y1 and Y2 of the poles 30A and 30B is equal to the distance L2.
Even if it is set smaller, the function of swingably supporting each of the pawls 30A and 30B does not decrease.

In the seat lifter of the present embodiment, from this viewpoint, the distances L1 and L2 are set so as to 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.
Can be reduced in the height direction. That is, the weight and cost of the seat lifter can be reduced without deteriorating the function of each element.

The seat lifter of the present embodiment is slidably fitted in a guide member 27 having an arc-shaped long hole 29 formed about the rotation axis X of the handle 3. In addition, the first and second poles 30A, 30
Pole supporting members 31A and 31B for swingably supporting B
The end portions 29A and 29B of the elongated hole 29 are configured to serve as stoppers for the pole support members 31A and 31B. The long hole 29 of the guide member 27 enables the first and second pawls 30A and 30B to revolve around the rotation axis X while correctly guiding the same, and furthermore, each end 29A and 29B of the long hole 29.
Has a function as a stopper for stopping each of the poles 30A and 30B.
It is not necessary to separately provide a guide member for guiding A and 30B 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 support members 31A, 31B
And the first and second poles 30A,
Although 30B is swingably supported, one pole support member may be provided, and the first and second poles 30A and 30B may be swingably supported by the one pole support member.

Further, the sheet lifter of the present embodiment includes:
Claw portions 34A, 3 of the first and second poles 30A, 30B
A spring 38 is provided as an example of an urging means for urging each of the pawls 30A and 30B toward the teeth 35 of the ratchet wheel 26 so that the teeth 4B are securely engaged with the teeth 35 of the ratchet wheel 26. Thus, the ratchet wheel 26 can be correctly rotated by the revolution of the first and second pawls 30A and 30B. In addition, the spring 38 includes the first and second pawls 30A, 3A.
Since one plate spring is provided with the holding portions 38A and 38B that hold both the first and second OBs, the structure of the spring 38 can be simplified.

Next, the brake mechanism 9 will be described.
The cross section of the brake mechanism 9 is shown in FIGS. 5 and 6 described above, and FIG. 11 is a cross section (cross section) of the brake mechanism 9 in a direction orthogonal to FIGS. 5 and 6. ing.

As can be seen from FIGS. 5, 6 and 11, the brake mechanism 9 has a case 42 fixed to the lifter support 8, and this case 42 is formed in a cup shape with one end side opened. Have been. Also, this case 42
It has a small-diameter annular wall 42A and a large-diameter annular wall 42B that are concentric about the rotation axis X of the handle shaft 21. It is integrated via the end wall 42C, and the inside of the small diameter annular wall 42A is hollow.

In the case 42, a core (first rotating body) 43 having a substantially fan-shaped cross section is rotatably accommodated. The handle shaft 21 and the core 43 are fixed to each other,
These can integrally rotate about the above-mentioned rotation axis X.

An annular groove 44 is formed in the core 43 about the rotation axis X. A small-diameter annular wall 42A of the case 42 is fitted in the annular groove 44, and a small-diameter coil spring (torsion) is fitted inside the small-diameter annular wall 42A. (Spring) 45A. The outer peripheral surface of the core 43 and the case 42
A large-diameter coil spring (torsion spring) 45B is disposed between the large-diameter annular wall 42B and the inner peripheral surface of the large-diameter annular wall 42B. As is apparent from FIGS. 5 and 6, each coil spring 45A, 45B
In at least one embodiment, at least the wound portion of the laminated spring is formed in a square (square) cross-sectional shape, and in the free state, the outer edge of the wound portion having a square cross-section with respect to the corresponding annular wall of the case 42. The parts come into contact.
That is, the small-diameter coil spring 45A engages with the inner peripheral surface of the small-diameter annular wall 42A of the case 42 at an outer edge formed in a cylindrical surface having substantially no irregularities. Similarly, the large-diameter coil spring 45 </ b> B engages with the inner peripheral surface of the large-diameter annular wall 42 </ b> B of the case 42 at the outer edge of the winding portion formed in a substantially flat cylindrical surface. In short, in the springs 45A and 45B having such a rectangular cross-sectional shape, the contact area with the annular wall of the case 42 can be widened.

Further, a stopper plate (second rotator) 46 is rotatably housed in the case 42, and the stopper plate 46 is also provided in the annular groove 4 around the rotation axis X.
A small-diameter annular wall 42A of the case 42 and a small-diameter coil spring 45A are arranged in the annular groove 47. The large-diameter coil spring 45B is also located between the outer peripheral surface of the stopper plate 46 and the inner peripheral surface of the large-diameter annular wall 42B of the case 42. The handle shaft 21 is relatively 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 radial wall surface 50A of the core 43, and the other end 49B of the coil 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
3 is engageable with the other radial wall surface 50B, and the other end 52B of the coil spring 45A is
6 is locked in a hole 51B formed in the hole 6. FIG.
In FIG. 1, the end 49A of the large-diameter coil spring 45B and the end 52A of the small-diameter coil spring 45A are separated from the radial wall surfaces 50A and 50B of the core 43, respectively. The gap in the direction is provided for play when operating the steering wheel.

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

Here, when the handle 3 is rotated in the first direction A to rotate the ratchet wheel 26 and the handle shaft 21 in the first direction A as described above,
The core 43 in the case 42 also rotates in the same first direction A. Thus, the other radial wall surface 50B of the core 43 presses the one end 52A of the small-diameter coil spring 45A, whereby the small-diameter coil spring 45A reduces its diameter, and the small-diameter coil spring 45A and the small-diameter annular wall of the case 42. The pressure contact force with 42A decreases. 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 radial wall surfaces 50A of the core 43 remains in the large-diameter coil spring 45B. Is engaged with one end 49A and pressurized. As a result, the diameter of the large-diameter coil spring 45B is reduced, and the pressure contact force between the large-diameter coil spring 45B and the large-diameter annular wall 42B of the case 42 is reduced. 2 in the direction B.

On the other hand, when a large load is applied to the seat cushion 1 when the seat cushion 1 is at the uppermost position and a seated person sits on the seat cushion 1, for example, as shown in FIG. On the rack 11, a rotational force in a direction in which the rack 11 rotates in the temporal direction in FIG.
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 portion 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 increases, and the outer edge of the large-diameter coil spring 45B is extended. A large frictional force acts between the portion and the inner peripheral surface of the large-diameter annular wall 42B of the case 42. Therefore, the pinion 6 is locked without rotating in the second direction B.
Thus, even if a large load is applied to the seat cushion 1, the seat cushion 1 does not lower.

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 enlarges its diameter, and
A large frictional force acts between the outer edge of 5A and the inner peripheral surface of the small-diameter annular wall 42A of the case 42. For this reason, the pinion 6 and the stopper plate 46 are prevented from rotating in the first direction A.

As described above, the brake mechanism 9 allows the rotation of the handle shaft 21 to be transmitted to the stopper plate 46 and the pinion 6. When a rotational force is applied from the first side, the stopper plate 46 and the pinion 6 are prevented from rotating. By providing the brake mechanism 9, even if an external force is applied to the seat cushion 1 after adjusting the height of the seat cushion 1,
The seat cushion is prevented from lowering or rising, and the height of the seat cushion 1 can be favorably maintained.

The seat lifter of the present embodiment has a handle 3
A transmission mechanism including a ratchet mechanism is provided between the seat cushion 1 and the lift mechanism 7, and the handle 3 is repeatedly moved back and forth between the neutral position and either the forward or reverse moving end to raise and lower the seat cushion 1. In order to avoid an excessive number of operations of the handle 3, the lift mechanism 7
Is not provided with a speed reduction mechanism for transmitting the rotation of the steering wheel 3 at a reduced speed. Therefore, as described above, when a load is applied to the seat cushion 1, the brake mechanism is required to operate more quickly and exert a stronger braking force than the type having such a speed reduction mechanism. .

To cope with this, in the brake mechanism 9 of this embodiment, the small-diameter coil spring 45A and the large-diameter coil spring 4
5B is formed so that the cross-sectional shape of the winding portion is square and engages with the corresponding annular walls 42A and 42B in a wide cylindrical surface area. Therefore, the small-diameter coil spring 45 </ b> A
Alternatively, when the diameter of the large-diameter coil spring 45B is enlarged, the small-diameter coil spring 45A or the large-diameter coil spring 45B quickly falls within the annular wall 42A or 42B without causing a tilt (angle change) in the axial direction. It can be pressed against the peripheral surface. Further, even if there is a slight difference in the roundness between the annular walls 42A, 42B and the small-diameter coil spring 45A, the large-diameter coil spring 45B, the contact area is wide, so that the pressure contact force is not easily affected. Further, if the contact area is large, the load burden per unit area is reduced, so that it is possible to prevent a part of the inner peripheral walls of the annular walls 42A and 42B from being worn due to aging. For the above reasons, the brake mechanism 9 can minimize the delay until the brake is applied when the load is applied to the seat cushion 1, that is, the unnecessary lifting and lowering operation of the seat cushion 1. After the brake is applied, the small-diameter coil spring 45A or the large-diameter coil spring 45B is pressed against the wall 42A or 42B in a wide surface area, so that a strong braking force is obtained. As is clear from the above, the brake mechanism 9 of the present embodiment can quickly and surely lock the seat cushion 1 when a load is applied to the seat cushion 1, so that the lift mechanism 7 is particularly provided with the speed reduction mechanism. It can be said to be suitable for use in a sheet lifter that does not have

In this embodiment, a seat lifter for a seat provided in the interior of a vehicle has been described as an example. However, the present invention is not limited to this, and it is needless to say that the present invention can be widely applied to seat lifters of various other types of seats.

Next, a second embodiment of the seat lifter will be described with reference to FIGS. This second embodiment is also widely applicable to various seats including automobiles.

As shown in FIGS. 12 and 13, the seat track 60 has a lower rail 61 fixed to the floor side.
And an upper rail 62 movably engaged with the lower rail 61. On the upper rail 62, a lower arm 63 provided with a seat cushion is provided. The lower arm 63 is raised and lowered with respect to the upper rail 62 by a lift mechanism 65 provided on the upper rail 62 of the seat track 60 and the lower arm 63. In FIGS. 12 and 13, the right side in the figures is the front of the seat, and the left side is the rear of the seat.

The structure of the lift mechanism 65 is basically the same as that of the first embodiment, and only the outline will be described. The front link 66 is rotatably provided at the lower end at a front portion on the upper rail 62 using a pin 66a and at the upper end at a front portion of the lower arm 63 using a pin 66b. The rear link 67 is rotatably provided at the lower end thereof at the rear of the upper rail 62 using a pin 67a and at the upper end thereof at the rear of the lower arm 63 using a pin 67b. The front link 66 and the rear link 67
, Upper rail 62 and lower arm 63 constitute a four-bar rotation mechanism. Therefore, the front link 6
6. By swinging at least one of the rear links 67 with respect to the upper rail 62 of the seat track 60, the lower arm 63 moves up and down with respect to the upper rail 62.

This lift mechanism 65 is shown in FIGS.
Is driven by using a handle mechanism 70 provided on the back side of the lower arm 63 in FIG. A hinge pin (handle shaft) 72 that is rotationally driven by a handle 71 of the handle mechanism 70 drives a pinion 73 via a brake mechanism 100 (details will be described later) that is also provided on the back surface of the lower arm 63. . Brake mechanism 1
00 indicates that the rotation of the hinge pin 72 is prohibited with respect to the rotation force from the pinion 73, and the hinge pin 72 is rotatable with respect to the rotation force from the handle 71.

On the lower arm 63 near the pinion 73, there is provided a gear 74 composed of a large-diameter gear 74a and a small-diameter gear 74b provided coaxially and rotating integrally. It is in mesh with the gear 74a. On the lower arm 63 near the gear 74, an intermediate portion of the gear arm 75 is rotatably provided using a pin 75a. At one rotation end of the gear arm 75, a sector gear portion 76 meshing with the small-diameter gear 74b of the gear 74 is formed. One end of a link 77 is rotatably attached to the other rotating end of the gear arm 75 using a pin 77a, and the other end of the link 77 is attached to a side of the rear link 67 using a pin 77b. The part is rotatably mounted. Therefore, when the hinge pin 72 rotates, the rear link 67 is driven to swing via the pinion 73, the gear 74, the gear arm 75, and the link 77, and the lower arm 63 moves up and down with respect to the seat track 60.

The handle mechanism 70 will be described with reference to FIGS. The base plate 7 is provided so as to cover the brake mechanism 100 provided on the lower arm 63.
8 are provided. The handle 71 inserted between the brake mechanism 100 and the base plate 78 includes an operation input unit (a handle 79 described later) and an opposite end (a slot 8 described later).
1 is rotatably attached to the base plate 78 using pins 78a.

A handle 79 made of resin is attached to one end of the handle 71. On the other hand, as shown in FIG. 14, the hinge pin 72 pushes the brake
0 so as to be rotatable. At the other end of the handle 71, an arc-shaped long hole 81 centering on a pin 78a pivotally connecting the handle 71 to the base plate 78 is formed. In this long hole 81, a hinge pin 72 protruding from the brake mechanism is formed. It is loose fit.

A ratchet wheel 82 is fixed to the hinge pin 72 between the handle 71 and the brake mechanism 100 by a method such as serration. Hinge pin 7
2 includes an E-ring 83 that can contact the base plate 78.
And the hinge pin 72 is prevented from coming off in the lower arm 63 direction. The lower arm 63 has a hinge pin 7
A hole 84 into which the loose fitting 2 is fitted is formed, and a vertical plate 85 for suppressing the play of the hinge pin 72 is fixed.

In the base plate 78, one end of the base plate 78 is provided with pins 87 and 87 ′ as the intermediate portions of poles 86 and 86 ′ as first and second poles provided so as to sandwich the ratchet wheel 82. It is provided rotatably. On one end side of each of the pawls 86 and 86 ′, a tooth 8 meshable with a tooth on an outer peripheral portion of the ratchet wheel 82 is provided.
8,88 'are formed. In addition, each pole 86,8
On the other end side of the handle 6 ', a handle contact portion 9 formed on the handle 71 with which a pole contact portion 89, 89' can contact.
0, 90 'are formed.

Further, on the other end side of each of the pawls 86 and 86 ′, a bent portion 91 bent toward the lower arm 63 is provided.
A spring (tensile spring) 92 as a first biasing means, one end of which is locked to the bent portion 91 and the other end of which is locked to the bent portion 91 ', is provided with the poles 86, 91'. 8
6 ′ is urged in a direction in which the teeth 88, 88 ′ are separated from the ratchet wheel 82, and the handle contact portions 90, 90 ′ of the respective poles 86, 86 ′ are brought into contact with the pole contact portions 89, 89 ′ of the handle 71. Abut.

At this time, the hinge pin 72 is located at a substantially intermediate position of the long hole 81 of the handle 71. Ends 94 and 95 of a spring 93 as second urging means provided so as to wind around the outer periphery of the brake mechanism 100 extend in a direction away from the handle 79 of the handle 71.

The base plate 78 on the side opposite to the handle 79 side of the handle 71 is bent to form the end 9 of the spring 93.
A bent portion 96 is formed between 4, 95. Further, on the lower arm 63, the end 9 of the spring 93 is provided.
A spring hook 97 located between 4, 95 is attached.

Next, the brake mechanism 100 will be described with reference to FIG. 14, FIG. 15, and FIG. The brake mechanism 100 has basically the same configuration as the brake mechanism 9 of the first embodiment. That is, the case 101 attached to the lower arm 63 has the concentric small-diameter annular wall 101A and the large-diameter annular wall 101B, and the small-diameter annular wall 101A and the large-diameter annular wall 101B are connected by the end wall 101C. The end face of the case 101 opposite to the end wall 101C is open. In the case 101, a small-diameter coil spring 102 is disposed so as to engage with the inner peripheral surface of the small-diameter annular wall 101A.
1B so as to be engaged with the inner peripheral surface. In each of the coil springs 102 and 103, the wound portion of the laminated spring is formed in a square (quadrangle) cross-sectional shape. The outer edge of the winding portion, which forms a substantially flat cylindrical surface, engages with the surface.

The central portion of the hinge pin 72 has a non-circular cross-sectional shape, and a core (first rotating body) 104 having a substantially fan-shaped cross-sectional shape is fitted into the non-circular cross-sectional portion. It rotates integrally with the hinge pin 72. An annular groove 105 is formed in the core 104 about the rotation axis of the hinge pin 102. The small-diameter annular wall 101A of the case 101 fits into the annular groove 105, and the small-diameter annular wall 101A is fitted inside the small-diameter annular wall 101A. Coil spring 102
Is arranged. Further, the large-diameter coil spring 103 described above is disposed between the outer peripheral surface of the core 104 and the inner peripheral surface of the large-diameter annular wall 101B of the case 101.

A stopper plate (second rotating body) 106 formed integrally with the pinion 73 has a through hole 107.
The hinge pin 72 is inserted into the through hole 107 so as to be relatively rotatable. This stopper plate 106
In addition, the hinge pin 72 has an annular groove 1 centered on the rotation axis.
The small-diameter annular wall 101A of the case 101 and the small-diameter coil spring 102 are arranged in the annular groove 108. Further, the large-diameter coil spring 103 described above is also located between the outer peripheral surface of the stopper plate 106 and the inner peripheral surface of the large-diameter annular wall 101B of the case 101.

One end 109 of the large-diameter coil spring 103
A is capable of engaging with one radial wall surface 110A of the core 104, and the other end 109B of the large-diameter coil spring 103.
Are locked in holes 111A formed in the stopper plate 106. One end 112A of the small-diameter coil spring 102 can engage with the other radial wall surface 110B of the core 104, and the other end 1 of the small-diameter coil spring 102 can be engaged.
12B is a hole 111 formed in the stopper plate 106.
B.

The hinge pin 72 is provided with an E-ring 113 that can be brought into contact with the core 104, and prevents the hinge pin 72 from coming off in the direction of the handle 71.

Next, the operation of the seat lifter of the present embodiment having the above configuration will be described. In a state where the handle 71 is not operated, that is, in a state where no rotational force acts on the hinge pin 72, a rotational force acts on the pinion 73 side, and the stopper plate 106 of the brake mechanism 100 is moved in either the clockwise or counterclockwise direction. When the rotational force is applied, the end portion 109B of the large-diameter coil spring 103 and the small-diameter coil spring 1 are inserted into the holes 111A and 111B of the stopper plate 106.
02 is locked, the diameter of the large-diameter coil spring 103 or the small-diameter coil spring 102 is immediately expanded, and the large-diameter coil spring 103 and the large-diameter annular wall 101B of the case 101 or the small-diameter coil The pressing force between the spring 102 and the small-diameter annular wall 101A of the case 101 increases, and large braking force is generated. Therefore, the rotation of the pinion 73 is prohibited without play in either the clockwise or counterclockwise direction on the pinion side.

Like the brake mechanism 9 of the previous embodiment,
Also in the brake mechanism 100 of this embodiment, the small-diameter coil spring 102 and the large-diameter coil spring 103 are formed so that the cross-sectional shape of the winding portion is square, and the corresponding annular wall 101 is formed.
A and 101B are configured to engage in a wide cylindrical contact area. Therefore, when the coil spring is pressed against the annular wall, the coil spring does not fall down in the axial direction, and the coil spring can be quickly pressed against the annular wall. After pressing, the coil spring presses against the annular wall in a wide area, so that a strong braking force can be maintained. That is, when a load is applied to the seat cushion, the seat cushion can be locked quickly and reliably.

In FIG. 12, a handle 79 of the handle 71 is provided.
Is pulled up, the handle 71 rotates about the pin 78a. Then, the pole contact portion 8 of the handle 71
9 pushes the handle contact portion 90 of the pole 86, and the pole 8
6 rotates about the pin 87 against the urging force of the spring 92, and the teeth 88 of the pawl 86
Mesh with. At substantially the same time, the upper end of the elongated hole 81 of the handle 71 abuts on the hinge pin 72. Thereafter, the center of rotation of the handle 71 becomes the hinge pin 72, and the handle 71
Is transmitted via the ratchet wheel 82 to the hinge pin 72 to which the ratchet wheel 82 is fixed, and the hinge pin 72 rotates clockwise. At this time,
The base plate 78 also rotates about the hinge pin 72,
The bent portion 96 pushes the end portion 95 of the spring 93, and elastically deforms the spring 93 in the diameter reducing direction.

When the hinge pin 72 rotates clockwise,
The core 104 also rotates clockwise, and in FIG. 17, the radial wall surface 110B of the core 104
With the end 112A. Then, the small-diameter coil spring 1
02 receives a force in the direction of reducing the diameter and receives a small-diameter coil spring 10.
The pressing force between the second member 101 and the small-diameter annular wall 101A of the case 101 is reduced, the core 104 becomes rotatable, and the pinion 73 rotates counterclockwise in FIGS. 12 and 13 via the stopper plate 106.

The rotation of the pinion 73 in the counterclockwise direction causes
The lower arm 63 is the upper rail 6 of the seat track 60.
Down for 2. When the desired height is obtained, the operating force of the handle 71 on the handle 79 is released. Then, the elastic restoring force of the spring 93 causes the base plate 78,
The handle 71 returns to the neutral position. Further, due to the elastic restoring force of the spring 92, the handle 71 rotates and returns until the hinge pin 72 is located at a substantially intermediate position of the elongated hole 81.

On the other hand, in FIG. 12, when the handle 79 of the handle 71 is pushed down, the handle 71
Rotate around a. Then, the pole contact portion 89 'of the handle 71 pushes the handle contact portion 90' of the pole 86 ', and the pole 86' rotates around the pin 87 against the urging force of the spring 92, and the pole 86 ' The teeth 88 ′ mesh with the ratchet wheel 82. Almost simultaneously, handle 7
The lower end of one long hole 81 contacts the hinge pin 72, and thereafter, the center of rotation of the handle 71 is the hinge pin 72, and the rotation of the handle 71 is controlled by the ratchet wheel 82.
Is transmitted to the hinge pin 72 to which the ratchet wheel 82 is fixed, and the hinge pin 72 rotates counterclockwise. At this time, the base plate 78 is also connected to the hinge pin 7.
2, the bent portion 96 pushes the end portion 94 of the spring 93, and elastically deforms the spring 93 in the diameter reducing direction.

When the hinge pin 72 rotates counterclockwise, the core 104 also rotates counterclockwise. In FIG. 17, the radial wall surface 110A of the core 104 engages with the end 109A of the large-diameter coil spring 103, Large diameter coil spring 10
3 receives a force in the direction of reducing the diameter. Therefore, the pressure contact force between the large-diameter coil spring 103 and the large-diameter annular wall 101B of the case 101 is reduced, the core 104 becomes rotatable, and the pinion 73 is rotated via the stopper plate 106 in FIGS. Rotate in the direction.

When the pinion 73 is rotated clockwise, the lower arm 63 is moved to the upper rail 62 of the seat track 60.
Rise against. When the desired height is obtained, the operation force on the handle 79 of the handle 71 is released. Then, the base plate 78 and the handle 71 return to the neutral position by the elastic restoring force of the spring 93. Further, due to the elastic restoring force of the spring 92, the handle 71 rotates and returns until the hinge pin 72 is located at a substantially intermediate position of the elongated hole 81.

In the above-described seat lifter of this embodiment, the teeth 88 and 88 ′ of the first and second poles 86 and 86 ′ mesh with the ratchet wheel 82 when the handle 71 is not operated. Absent. Only when the handle 71 is rotated, the pole 86 or 8
The rotation is transmitted to the ratchet wheel 82 via 6 ′, and the hinge pin 72 is rotated. That is, handle 7
When the handle 71 is not operated, the mechanical connection between the handle 71 and the hinge pin 72 is released between the handle 1 and the hinge pin 72 (core 104), and the handle 71 is moved from the neutral position to the forward / reverse moving end. A handle interlocking control mechanism is provided for mechanically connecting the handle 71 to the hinge pin 72 (core 104) and transmitting power to the lift mechanism 65 only when the handle 71 is rotated. Therefore, it is possible to prevent an external impact from directly acting on the handle mechanism, thereby preventing damage to the handle mechanism.

In the seat lifter of this embodiment, the operation mode in which the seat 71 is moved up and down by reciprocating the handle 71 in the forward or reverse rotation direction from the neutral position is the same as the seat lifter of the first embodiment. 12 and 13 are provided with the gear 74 for transmitting the rotation of the hinge pin 72 at a reduced speed. However, it is possible to prevent the number of reciprocating operations of the handle 71 at the time of raising and lowering the seat from being excessively performed, thereby deteriorating the operability. Therefore, the reduction ratio cannot be so large. Therefore, also in the seat lifter of the present embodiment, a brake mechanism that operates quickly and exerts a strong braking force when a load is applied to the seat without operating the handle 71 is required. As described above, in the brake mechanism 100 of the present embodiment, the coil spring 10
The cross-sectional shape of the winding portions 2 and 103 is square, and the coil springs 102 and 103 can be fixed to the annular walls 101A and 1010 without falling in the axial direction when a force in the radially expanding direction is applied.
1B, the braking force can be exerted without delay with respect to the load on the seat cushion. Further, since the coil springs 102 and 103 are pressed against the annular walls 101A and 10B in a wide contact area, the braking performance is high.

For comparison with the present invention, a comparative example using a coil spring having a round cross section of a winding portion to be brought into contact with an annular wall in a brake mechanism of a seat lifter is shown in FIGS.
It was shown to. Although only the brake mechanism 200 is shown in the figure, it is assumed that the brake mechanism 200 is mounted on a seat lifter in place of the brake mechanisms 9 and 100 according to the first or second embodiment. In order to avoid repetition of the description, in the brake mechanism 200, the same components as those of the previous embodiment are denoted by the same reference numerals as those of the brake mechanism 9, and the specific description is omitted.

In the brake mechanism 200, each of the small-diameter coil spring 202 and the large-diameter coil spring 203 has a round cross section at the winding portion. Therefore, FIG.
As shown in FIG. 20, each coil spring 202, 2
03 is engaged with the inner peripheral surfaces of the small-diameter annular portion 42A and the large-diameter annular portion 42B in a linear narrow region on the outer edge of the winding portion.

Small-diameter coil spring 202 and large-diameter coil spring 2
In the reference numeral 03, one end portions 204A and 205A are locked in holes 51A and 51B of the stopper plate 46, and the other end portions 204B and 205B can be engaged with the radial wall surfaces 50A and 50B of the core 43. ing. Therefore,
When the core 43 is rotated in the forward and reverse directions via the handle, the diameter coil spring 202 or the large diameter coil spring 203 is rotated.
Is reduced, the pressure contact force between the annular wall 42A and 42B is reduced, and the stopper plate 46 and the pinion 6 are rotated in the same direction as the core 43.

On the contrary, a load is applied to the seat cushion,
When the force for rotating the stopper plate 46 and the pinion 6 is applied, the following problem may occur in the present brake mechanism using a coil spring having a round cross section. For example, in FIG. 19, when a rotational force in the direction of arrow B acts on the stopper plate 46 due to a load on the seat cushion, the end 205A of the large-diameter coil spring 203 receives a moving force in the direction B. Here, if the large-diameter coil spring 203 immediately performs the diameter-expanding operation and presses against the large-diameter annular wall 42B, the stopper plate 46 is not rotated and is substantially rotated as shown in FIG.
Is locked at the position. However, the large-diameter coil spring 2
Reference numeral 03 denotes a shape in which the wound portion having a circular cross-section comes into contact with the large-diameter annular wall 42B, so that it can easily fall down with respect to the rotation axis X as shown by an arrow C in FIG. When such a fall occurs, the time required for the large-diameter coil spring 203 to come into pressure contact with the large-diameter annular wall 42B to exert a braking action is delayed, and the stopper plate 46 and the pinion 6 are rotated by the angle θ shown in FIG. Only rotate and then brake. In other words, the brake starts to work after the seat cushion moves by a certain amount. If the lift mechanism does not have a speed reduction mechanism, or if the reduction ratio is small, the seat cushion moves up and down by an amount corresponding to the rotation angle of the stopper plate 46 and the pinion 6 or by an amount close thereto. The movement amount cannot be ignored. Here, the large-diameter coil spring 203 has been described, but when the stopper plate 46 receives a rotational force in the direction of arrow A in FIG. 19, the same problem may occur with the small-diameter coil spring 202.

When the small-diameter coil spring 202 and the large-diameter coil spring 203 are pressed against the annular walls 42A and 42B, the cross-sectional rigidity of the round-shaped coil spring is smaller than that of the square-shaped coil spring. It is difficult to obtain a high braking force as compared with the brake mechanisms 9 and 100 of the embodiment described above.

When there is a difference in roundness between the coil spring and the annular wall, it is difficult to exhibit good braking performance if the coil spring has a circular cross section and a small contact area with the annular wall. That is, the start of braking may be delayed, or sufficient braking force may not be obtained.

Furthermore, since the coil spring having such a circular cross section engages with the annular wall in a narrow linear region, the load is concentrated on the narrow engagement region in the annular wall, and the annular wall is formed with the passage of time. The peripheral surface may be worn. This results in an increase in the inner diameter of the annular wall, which causes a reduction in response during braking.

On the other hand, as described above, the brake mechanisms 9 and 100 in which the cross-sectional shape of the coil spring winding portion which comes into contact with the annular wall has a rectangular cross section can provide good braking without the above-mentioned problems. Since it can exhibit performance, it is particularly suitable for use in a sheet lifter of a type in which a sheet is raised and lowered by reciprocating a handle from a neutral position as in each embodiment.

[0101]

As described above, according to the present invention, it is possible to obtain a seat lifter which can quickly and reliably regulate the operation of the seat when a load is applied to the seat without operating the steering wheel. it can.

[Brief description of the drawings]

FIG. 1 is a side view of a seat to which a seat lifter according to the present invention is applied.

FIG. 2 is a view showing a lift mechanism when a seat cushion is at an intermediate height position.

FIG. 3 is a diagram showing the lift mechanism when the seat cushion is at the highest position.

FIG. 4 is a diagram showing the lift mechanism when the seat cushion is at the lowest position.

FIG. 5 is a cross-sectional view of a handle, a ratchet mechanism, and a brake mechanism.

FIG. 6 is an exploded cross-sectional view showing the elements of FIG. 5;

FIG. 7 is a view showing a handle and a ratchet mechanism.

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

FIG. 9 is a diagram illustrating a meshing state between a pawl portion of a pole and a ratchet wheel.

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

FIG. 11 is a cross-sectional view of the brake mechanism shown in FIGS. 5 and 6;

FIG. 12 shows a sheet lifter according to another embodiment of the present invention.
It is a side view of a seat cushion lowering state.

13 is a side view showing a state where the seat cushion is raised from the state of FIG.

FIG. 14 is a sectional view taken along section line XIV-XIV in FIG. 16;

FIG. 15 is a sectional view taken along section line XV-XV in FIG. 16;

FIG. 16 is a side view of a handle and an interlocking control mechanism thereof.

FIG. 17 is a transverse sectional view of the brake mechanism shown in FIGS. 14 and 15;

FIG. 18 is a longitudinal sectional view of a brake mechanism showing a comparative example with a brake mechanism mounted on a seat lifter of the present invention.

FIG. 19 is a cross-sectional view of the brake mechanism of FIG.

FIG. 20 is a side sectional view showing a state where the brake starts to work in the brake mechanism of FIGS. 18 and 19;

FIG. 21 is a cross-sectional view of the brake mechanism of FIG.

[Explanation of symbols]

 Reference Signs List 1 seat cushion 3 71 handle 6 73 pinion 7 65 lift mechanism 8 lifter support 9 100 brake mechanism 21 handle shaft 26 82 ratchet wheel 30A 86 first pole 30B 86 'second pole 35 teeth (ratchet teeth) 36 cam 37A 37B Projection 38 Spring (Pole biasing means) 34A 34B Claw 39 Return spring 42 101 Case 42A 101A Small-diameter annular wall 42B 101B Large-diameter annular wall 42C 101C End wall 43 104 Core (first rotating body) 45A 102 Small-diameter coil Spring 45B 103 Large-diameter coil spring 46 106 Stopper plate (second rotating body) 50A 50B 110A 110B Radial wall surface 63 Lower arm 70 Handle mechanism 72 Hinge pin (handle shaft) 78 Base plate 7 a pin 81 elongated holes 89 89 'pole abutting portion 90 90' the handle abutment 92 spring (urging means) 93 spring 93 (second biasing means) X rotation axis Y1 Y2 pivot axis

Claims (5)

[Claims] 1. A handle having a neutral position and rotatable between a neutral position and a forward / reverse moving end; reciprocating operation between the neutral position and a forward moving end; A first rotating body which is provided with rotation in the forward and reverse directions by a reciprocating operation with the direction moving end; a second rotation which is coaxial with the first rotating body and rotates in conjunction with the elevating operation of the sheet A small-diameter annular wall and a large-diameter annular wall provided concentrically with the first and second rotating bodies; one end of which is locked to the second rotating body, and the other end of which is the first rotating body. A small-diameter coil spring which is detachable from one of the pair of radial walls and whose outer edge is engaged with the inner peripheral surface of the small-diameter annular wall in a free state; and one end of which is locked to the second rotating body. , The other end of which can be disengaged from the other of the pair of radial wall surfaces of the first rotating body, and the outer edge portion thereof in a free state. A large-diameter coil spring engaged with the inner peripheral surface of the large-diameter annular wall; the small-diameter coil spring and the large-diameter coil spring each include at least a winding portion of a laminated spring that comes into contact with the small-diameter annular wall and the large-diameter annular wall. Is formed in a rectangular shape; when a load is applied to the seat in a state where the handle is not operated, the small diameter or the large diameter of the small diameter or the large diameter is increased by a rotational force acting on the second rotating body. The outer diameter of the small- or large-diameter coil spring having a rectangular cross-sectional shape is pressed against the inner peripheral surface of the small-diameter annular wall or the large-diameter annular wall to regulate the rotation of the second rotating body. When the first rotating body is rotated in the normal or reverse direction via the handle, the end of the small- or large-diameter coil spring is controlled by a radial wall surface of the first rotating body. Part is pressed Seat lifter, characterized in that the small diameter or large diameter coil spring is allowed rotation of said reduced diameter second rotor sheet is elevating. 2. A handle having a neutral position and rotatable between a neutral position and forward and reverse moving ends; a first rotating body rotatable about a rotation axis of the handle; A second rotating body which is coaxial with the body and is rotatably supported relative to the first rotating body and has a pair of radial walls opposed to each other in the circumferential direction; A lift mechanism that is provided between the handle and the first rotating body; rotation from a neutral position to a forward / reverse moving end from the neutral position is transmitted to the first rotating body; A ratchet mechanism that does not transmit the rotation from the moving end to the neutral position to the first rotating body; a small-diameter annular wall and a large-diameter annular wall provided concentrically with the first and second rotating bodies; And a pair of radial walls of the first rotating body are fixed at the other end. A small-diameter coil spring whose outer edge is engaged with the inner peripheral surface of the small-diameter annular wall in a free state; and one end of which is locked to the second rotating body, and the other end of which is A large-diameter coil spring capable of engaging and disengaging with the other of the pair of radial walls of the first rotating body and having an outer edge engaged with an inner peripheral surface of the large-diameter annular wall in a free state; The large-diameter coil springs each have at least a cross-section of a winding portion of the laminated spring that comes into contact with the small-diameter annular wall and the large-diameter annular wall is formed in a rectangular shape; When a load is applied to the seat, the small- or large-diameter coil spring expands due to the rotational force acting on the second rotating body, and the outer edge of the small- or large-diameter coil spring having a rectangular cross-sectional shape is formed. The small diameter annular wall or large When the first rotating body is rotated in the normal or reverse direction via the handle, the rotation of the second rotating body is restricted by pressing against the inner peripheral surface of the radial annular wall to regulate the rotation of the second rotating body. The end of the small-diameter or large-diameter coil spring is pressed by the radial wall surface of the first rotary body, the small-diameter or large-diameter coil spring is reduced in diameter, and the second rotary body is allowed to rotate, A sheet lifter wherein a second rotator is rotated together with the first rotator to lift and lower a sheet via the lift mechanism. 3. The sheet lifter according to claim 2, wherein
A handle shaft fixed to the first rotating body and rotatably supported with respect to the handle; a ratchet wheel fixed to the handle shaft; a handle when the handle is rotated; First and second poles that perform a revolving operation about an axis and can swing about the revolving locus; formed on the first and second poles, mesh with ratchet teeth on an outer peripheral portion of a ratchet wheel. Claw part;
The claw portion formed on the first pole transmits the moving force to the ratchet teeth when the first pole makes the orbit in the forward direction, rotates the ratchet wheel, and makes the orbit in the reverse direction. Sometimes do not allow the ratchet teeth to transmit its movement; the claw formed on the second pole
When the second pole makes the orbit in the forward direction, the moving force is not transmitted to the ratchet teeth, and when the second pole makes the orbit in the reverse direction, the moving force is transmitted to the ratchet teeth to rotate the ratchet wheel. A pawl urging means for urging the first and second pawls to a swinging position at which the claw meshes with the ratchet teeth; and, when the handle is rotated in the normal or reverse direction, with the rotation of the handle. Of the first and second pawls that revolve with the pawl that does not transmit the moving force to the ratchet wheel to a position where the engagement between the pawl portion and the ratchet teeth is released. A seat lifter having a mechanism; 4. A handle having a neutral position and rotatable between a neutral position and a forward / reverse moving end; a first rotating body rotatable about a rotation axis of the handle; A second rotating body which is coaxial with the body and is rotatably supported relative to the first rotating body and has a pair of radial walls opposed to each other in the circumferential direction; A lift mechanism that is provided between the handle and the first rotating body, when the handle is not operated, releases the mechanical connection between the handle and the first rotating body, and lifts the handle from the neutral position. A handle interlocking mechanism for rotating the first rotating body in the direction opposite to the forward direction by mechanically connecting the handle to the first rotating body when the rotating operation is performed to the moving end side in the forward direction and the moving end side in the opposite direction. Control mechanism; said first and second
A small-diameter annular wall and a large-diameter annular wall provided concentrically with the rotator; one end portion of which is locked to the second rotator, and the other end portion is provided on one of a pair of radial wall surfaces of the first rotator. A small-diameter coil spring that can be disengaged and whose outer edge is engaged with the inner peripheral surface of the small-diameter annular wall in a free state; and one end is locked to the second rotating body, and the other end is the first rotary member. A large-diameter coil spring that can be engaged and disengaged with the other of the pair of radial walls of the rotating body, and whose outer edge portion engages with the inner peripheral surface of the large-diameter annular wall in a free state; Wherein each of the springs has at least a rectangular cross section of a winding portion of the laminated spring which comes into contact with the small-diameter annular wall and the large-diameter annular wall, and applies a load to the seat in a state where the handle is not operated. Is acted upon by the rotational force acting on the second rotating body. The small-diameter or large-diameter coil spring expands in diameter, and the outer edge of the small-diameter or large-diameter coil spring having a rectangular cross-sectional shape presses against the inner peripheral surface of the small-diameter annular wall or the large-diameter annular wall to form a second coil spring. When the first rotating body is rotated in the normal or reverse direction via the handle, the small diameter or the large diameter is controlled by the radial wall surface of the first rotating body. The end of the coil spring having the diameter is pressed, and the coil spring having the small diameter or the large diameter is reduced in diameter to allow the rotation of the second rotating body, and the second rotating body is rotated together with the first rotating body. A sheet lifter, wherein a sheet is moved up and down via the lift mechanism. 5. The sheet lifter according to claim 4, wherein
A handle shaft having a coaxial ratchet wheel fixed to the first rotating body; a handle shaft provided rotatably with respect to the handle shaft, and an intermediate portion connecting the handle shaft and the operation input unit; A base plate to which the handle is pivotally attached at a portion; a long hole formed in the handle, wherein the handle shaft is movably and rotatably fitted in a hole forming direction; an intermediate portion disposed so as to sandwich the handle; Is rotatably mounted on the base plate, and has teeth formed at one end thereof so as to be able to mesh with the teeth of the ratchet wheel, and the other end thereof has first and second poles to which the handle can abut. And urging means for urging the teeth of the first and second pawls in a direction away from the ratchet wheel; By the biasing means, the interlocking of the handle and the handle shaft is interrupted without the teeth of the first and second pawls meshing with the teeth of the ratchet wheel. The handle rotates with respect to the base plate until the handle comes into contact with the base plate, and the handle presses the first or second pawl so that its teeth mesh with the ratchet wheel, and a handle shaft is provided at an end of the long hole. After contact, the handle rotates together with the base plate about the handle shaft, and the rotation of the handle is transmitted to the ratchet wheel via the first or second pawl meshed with the ratchet wheel, and the handle shaft is rotated. A sheet lifter that rotates.