JP2594163Y2 - Brake mechanism - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a brake mechanism used for a lifter of a vehicle seat.

[0002]

2. Description of the Related Art For example, in a lifter for a vehicle seat,
The front and rear height and the left and right height of the seat are adjusted by operating the steering wheel, but a brake mechanism is generally provided so that the steering wheel does not rotate due to an excessive load input to the seat at the time of a collision or the like.

[0003] In such a brake mechanism, a spring, a core having a handle shaft, and a pinion cooperating with a seat up-and-down mechanism are provided inside a drum, and a claw portion of the pinion is fitted into a notch of the core. Makes it possible to abut one end of the spring and the other end to the notch side end of the core, so that the spring is expanded against the rotation of the pinion due to excessive load input to the pinion and pressed against the drum inner wall. While the rotation of the core is prevented, the spring is contracted for rotation on the handle shaft side to release from the inner wall of the drum, so that the pinion can be driven to rotate. Japanese Unexamined Patent Application, First Publication No. Sho.
No. Gazette, etc.).

[0004]

However, in the conventional brake mechanism, play is provided between the cutout of the core and the claw portion of the pinion due to its structure. The core was liable to rattle, the handle was rattled, and there was room for improvement in terms of commerciality.

[0005] In view of the above problems, it is an object of the present invention to provide a brake mechanism capable of eliminating rattling of a steering wheel.

[0006]

SUMMARY OF THE INVENTION Accordingly, a brake mechanism according to the present invention is provided such that a brake spring is provided inside a brake drum so as to press against the inner wall of the drum, and a brake shoe having a handle shaft is rotated inside the brake spring. A pinion which is freely housed and has a shaft hole in the center of which the handle shaft of the brake shoe is inserted is provided,
A claw portion of the pinion is fitted into the notch of the brake shoe, and one end of the brake spring is locked to the claw portion, and the other end can be brought into contact with a notch-side end of the brake shoe. On the other hand, the brake shoe is provided with a friction surface with which a brake spring contacts when the handle shaft rotates, and biases the pinion between the notch side edge of the brake shoe and the pinion in the rotation direction of the handle shaft. A spring is provided.

[0007] The friction surface of the brake shoe may be formed by forming a large number of fine irregularities, so-called dowels, to increase the frictional resistance.
A member having frictional resistance may be fixed.

[0008]

According to the present invention, when the handle shaft is rotated, the notch side edge of the brake shoe pushes the claw portion of the pinion, the brake spring contracts and is released from the inner wall of the drum, and the pinion is released. It rotates following the handle shaft.

At this time, the contracted brake spring contacts the friction surface of the brake shoe with a predetermined resistance, while the pinion is urged in the same direction by the spring, so that the contraction of the brake spring does not return. Therefore, the brake shoe is provided with a predetermined rotational resistance by the contracted brake spring, and the handle shaft can be prevented from rattling, thereby improving the commerciality.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to specific examples shown in the drawings. 1 to 4 show a brake mechanism according to an embodiment of the present invention. In the figure, a lifter 2 is provided on a seat cushion frame 1, and the lifter 2
Is provided with a brake mechanism 3 so that the vertical position of the seat can be adjusted by operating the handle, and the brake mechanism 3 prevents the rotation of the handle following the load from the seat side.

In the brake mechanism 3, as shown in FIGS. 2 and 4, the brake drum is composed of a main drum 30 and a sub-drum 31, and a flange 310 is formed at an upper end of the sub-drum 31. Has an engaging claw 311 protruding therefrom. On the other hand, an engagement groove 300 is formed on the upper end flange of the main drum 30, and the flanges of the sub drum 31 and the main drum 30 are overlapped and the engagement claws 311 are fitted into the engagement grooves 300, so that both are prevented from rotating. The sub-drum 31 covers the upper end opening of the main drum 30.

Two brake springs 32 are provided inside the main drum 30 so as to press against the inner wall of the drum, and a brake shoe 33 is housed in the brake spring 32. The brake shoe 33 has a cylindrical wall surface, and a pair of notches 331 are formed on the cylindrical wall surface.
Are formed facing each other, a friction surface 333 is formed on a wall surface between the notches 331, and a handle shaft 330 is provided on the brake shoe 33 so as to extend vertically, and a lower end of the handle shaft 330 is provided at a lower end of the handle shaft 330. A handle mounting portion 332 is formed, and the handle mounting portion 332 is protruded downward from an insertion hole of the main drum 30 and is rotatable. The friction surface 333 is formed by forming a large number of fine irregularities, so-called dowels.
A material having frictional resistance may be fixed.

Further, with respect to the brake shoe 33,
A pinion 34 having a shaft hole 343 into which the handle shaft 330 is inserted is provided at the center. The pinion 34
A gear 340 is formed at the upper end thereof, and a claw 341 having a locking slit 342 in the middle is formed at the lower end thereof so as to be able to abut the notch 331 side edge of the brake shoe 33. Have been. One end of each of the brake springs 32 is inserted and locked in the locking slit 342 of the claw 341, and the other ends of the both brake springs 32 can be brought into contact with the notch 331 side edge of the brake shoe 33. .

On the other hand, a spring 35 is provided between the sub-drum 31 and the pinion 4, one end of the spring 35 is inserted and locked in the locking slit 342 of the pinion 34, and the other end of the spring 35 is braked. Shoe 3
The third cutout 331 is in contact with the side edge of the cutout 331.

Therefore, when the pinion 34 is to rotate, the brake spring 32 expands and is pressed against the inner wall of the main drum 30 so that the driven rotation of the handle shaft 330 is prevented. The side edge pushes the claw 341 of the pinion 34, and the brake spring 32 is contracted to release the pressure contact from the inner wall of the main drum 30.
0 is driven and rotated.

At this time, when the brake spring 32 contracts, as shown in FIG. 3, the brake spring 32 comes into contact with the friction surface 333 of the brake shoe 33, but the pinion 34 is urged in the same direction by the spring 35. Therefore, the contraction of the brake spring 32 does not return, and the friction surface 333 of the brake shoe 33 is rubbed against the contracted brake spring 32 to apply a predetermined rotational resistance. The product can be improved by preventing rattling.

On the other hand, if an excessive load is input during a collision or the like, the brake shoe 33 starts rotating in the opposite direction by overcoming the urging force of the spring 35, and the brake spring 32 is expanded to The contact with the friction surface 333 is released, and at the same time, the brake spring 32 is pressed against the inner wall of the main drum 30, and the driven rotation of the handle shaft 330 is prevented. It should be noted that in the case of such an abnormality, the rattling of the steering wheel or the like is not a problem, and a similar operation may be performed when the steering wheel returns to a normal state to return the steering wheel to a state without rattling.

Further, the sub-drum 31 is
0, the sub-drum 31 is set to a height at which the sub-drum 31 can abut on the step portion of the pinion 34, whereby the vertical movement of the pinion 34 can be restricted, and the gear 340 interferes with the seat frame 1. Can be prevented.

Further, since two brake springs 32 are provided, the braking force can be increased and the load applied to the ends of the springs 32 can be dispersed, so that the durability of the brake springs 32 can be improved.

Although the brake drum has a double structure, it is constituted by the main and sub drums 30 and 31, so that the workability and assemblability of the drum do not deteriorate.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view showing a seat frame having a brake mechanism according to an embodiment of the present invention.

FIG. 2 is a partially sectional perspective view showing the brake mechanism.

FIG. 3 is an explanatory diagram for explaining an operation of the brake mechanism.

FIG. 4 is an exploded perspective view showing the brake mechanism.

[Explanation of symbols]

 3 Brake mechanism 30 Main drum (brake drum) 32 Brake spring 33 Brake shoe 330 Handle bar 331 Notch 333 Friction surface 34 Pinion 341 Claw 343 Shaft hole 35 Spring

Claims (1)

(57) [Scope of request for utility model registration] A brake mechanism in which a pinion can be driven to rotate by rotation of a handle shaft and a driven rotation of a handle shaft cannot be performed with respect to rotation of the pinion, wherein a brake spring is pressed against a drum inner wall in the brake drum. A brake shoe having a handle shaft is rotatably housed in the brake spring, and a pinion having a shaft hole through which the handle shaft of the brake shoe is inserted is provided at the center; The notch of the pinion is fitted with a claw portion of the pinion, one end of the brake spring is engaged with the claw portion, and the other end can be in contact with a notch side end of the brake shoe. The brake shoe is provided with a friction surface with which a brake spring comes into contact when the handle shaft is rotated. Brake mechanism, characterized in that spring biasing the pinion in the direction of rotation of the handle shaft is provided between the over notch-side edge and the pinion.