JP2021112985A - Brake device for automobile seat and method for manufacture thereof - Google Patents

Abstract

To provide a brake device for automobile seat which contributes down-sizing of a device, and a method for manufacture thereof.SOLUTION: In this brake device 7, a pair of regulation parts 121e, 122e, which are projected from an outer peripheral part of a deformed shank 12c, are brought in contact with an inner bottom surface of a housing 11 to regulate axial movement of a pinion shaft 12 to a seat side. Therefore, down-sizing of the pinion shaft 12 in an axial direction can be achieved by only an axial dimension of a flange part compared to when the flange part is provided in series in the axial direction with respect to the deformed shank 12c, thereby enabling contribution to down-sizing of the brake device 7.SELECTED DRAWING: Figure 5

Description

The present invention is for automobiles incorporated in a position adjusting mechanism such as a seat lifter mechanism for adjusting the height position of a seat cushion which is a seat surface of a seat and a reclining mechanism for adjusting an angular position of a seat back which is a backrest portion of a seat. The present invention relates to a seat braking device and a method for manufacturing the same.

As a braking device for an automobile seat of this type, for example, the one described in Patent Document 1 below has been proposed.

The brake device described in Patent Document 1 includes, for example, a pinion shaft incorporated in a seat lifter mechanism and linked with a position adjusting mechanism provided on an automobile seat so as not to rotate with respect to a reverse input from the pinion shaft. A brake portion that supports the pinion shaft and an operation portion for operating the pinion shaft are arranged so as to be overlapped in the axial direction.

The pinion shaft is inserted and arranged in a housing accommodating a brake element constituting the brake portion, and a lever bracket that rotates integrally with an operation lever of the operation portion is connected to one end side in the axial direction, and other On the end side, a pinion gear that faces the outside of the housing and meshes with the gear on the seat side is provided. Further, the pinion shaft is provided inside the pinion gear in the axial direction, and extends inward in the axial direction of the bearing portion and a bearing portion that is rotatably supported by a shaft hole formed through the bottom portion of the housing. An annular flange portion that is formed in diameter and is locked to the inner surface of the housing to regulate the axial movement of the pinion shaft, and an annular flange portion that is provided inside the flange portion in the axial direction and engages with the brake element. It has a surface width-shaped deformed shaft portion, and these are formed coaxially and integrally including the pinion gear.

JP-A-2018-090238

In recent years, there has been a demand for miniaturization of brake devices for automobile seats in addition to lock strength, and it is desired to shorten the axial dimension of the entire device and reduce the radial dimension.

However, in the brake device described in Patent Document 1, a circular recess for receiving the flange portion is formed in a stepped shape at the bottom of the housing, and the housing is axially outside by the amount of the recess. There was a problem that the housing was enlarged in the axial direction due to the protrusion.

The present invention has been made focusing on such a problem, and provides a brake device for an automobile seat and a method for manufacturing the same, which contributes to miniaturization of the device.

As one aspect of the brake device for an automobile seat according to the present invention, the automobile seat brake device includes a pinion shaft linked with a position adjusting mechanism provided on the automobile seat, and is supported so as not to rotate with respect to a reverse input from the pinion shaft. The brake unit and the operation unit for operating the pinion shaft are housed and arranged in a substantially cylindrical case so as to be overlapped in the axial direction of the pinion shaft, and the pinion shaft accommodates the case in the axial direction. One end that rotatably supports the case and projects outward in the axial direction from the case rotatably supports the operation lever for operating the operation unit, and more than the case. The other end projecting outward in the axial direction is connected to the position adjusting mechanism, and the pinion shaft is a pinion gear that faces the outside of the case and meshes with a gear provided in the position adjusting mechanism, and a pinion gear of the case. A two-sided width portion that faces a bearing portion that is rotatably supported by a shaft hole that is rotatably formed through a shaft hole formed through the bottom portion and a brake element that constitutes the brake portion, and is set smaller than the outer diameter of the bearing portion. A deformed shaft portion having a A pair of restricting portions for restricting the axial movement of the pinion shaft by contacting the bottom portion of the housing are integrally provided.

As a preferred embodiment of the pair of restricting portions, the deformed shaft portion has a substantially oval cross section in which the pair of two-sided width connecting portions have an arc shape, and the pair of restricting portions has the pair of two-sided widths. Each of the circumferential intermediate portions of the connecting portion is composed of a pair of protrusions formed so as to project radially outward from the bearing portion, and the pair of protrusions is an arc of the pair of widthwise connecting portions. It is desirable that the shape portion is formed into a flat shape extending along the radial direction of the pinion shaft by pressing the shape portion in the thickness direction of the width across flats and plastically deforming the shape portion.

As a preferred embodiment of the pair of protrusions, the pair of widthwise connecting portions includes a pair of arcuate portions having no pair of restricting portions in the axial direction, and the outer diameter of the arcuate portions is the said. It is desirable to have an outer diameter that is the same as the outer diameter of the bearing portion or slightly larger than that of the bearing portion.

As a preferred embodiment of the bearing portion, it is desirable that the bearing portion has an outer diameter substantially the same as the tooth tip circle of the pinion gear.

One aspect of the method for manufacturing a brake device for an automobile seat according to the present invention includes a pinion shaft linked with a position adjusting mechanism provided on the automobile seat, and does not rotate with respect to a reverse input from the pinion shaft. The bearing portion that supports the pinion shaft and the operation portion for operating the pinion shaft are housed and arranged in a substantially cylindrical case so as to be overlapped with each other in the axial direction of the pinion shaft. It penetrates in the direction and is rotatably supported by the case, and one end portion that protrudes outward in the axial direction from the case rotatably supports the operation lever for operating the operation portion and is rotatably supported by the case. The other end projecting outward in the axial direction is connected to the position adjusting mechanism, and the pinion shaft is a pinion gear that faces the outside of the case and meshes with a gear provided in the position adjusting mechanism, and the case. A bearing portion that is rotatably supported by a shaft hole formed through the bottom portion of the bearing portion and a two-sided width that faces the brake element constituting the brake portion and is set smaller than the outer diameter of the bearing portion. A deformed shaft portion having a portion is formed continuously in the axial direction, and a pair of two-sided width connecting portions connecting the two-sided width portions in the deformed shaft portion are connected outward in the radial direction of the pinion shaft. A pair of restricting portions that project and abut against the bottom of the case to regulate the axial movement of the pinion shaft are integrally provided, and a rod-shaped material is installed in the axial direction from one end side to form the deformed shaft portion. A step of forming a deformed shaft portion for forming the pinion shaft, a step of forming a gear in which the material is installed in the axial direction from the other end side to form the pinion gear, and a pair of directions orthogonal to the axial direction of the pinion shaft. By pressing a part of the two-sided width connecting portion in the thickness direction of the two-sided width portion to plastically deform it, a flatness extending along the radial direction to the circumferential intermediate portion of the pair of two-sided width connecting portions. It is characterized by comprising a regulation portion forming step for forming the pair of regulation portions in a shape.

As a preferred embodiment of the method for manufacturing a brake device for an automobile seat, it is desirable to further include a bearing portion cutting step of cutting the outer peripheral portion of the bearing portion to finish it to a required size after the regulation portion forming step.

According to the present invention, by forming a pair of restricting portions on the outer peripheral side of the deformed shaft portion, the axial dimension (thickness) of the flange portion is compared with the case where the flange portion is formed separately from the deformed shaft portion. ) Can be reduced in the axial direction of the pinion shaft, which can contribute to the miniaturization of the braking device.

FIG. 3 is a perspective view showing an example of an automobile seat provided with a seat lifter mechanism and a seat reclining mechanism as a position adjusting mechanism. As an embodiment of the brake device according to the present invention, a front view of the brake device used in the seat lifter mechanism shown in FIG. The left side view of the brake device shown in FIG. A left side view showing a state in which the lever bracket of the brake device shown in FIG. 3 is removed. FIG. 3 is a cross-sectional view taken along the line AA of FIG. FIG. 2 is an exploded perspective view of each component of the brake unit and the operation unit in the brake device shown in FIG. The explanatory view in the neutral state of the brake part shown in FIG. An enlarged view of the pinion axis shown in FIG. An enlarged view of the input lever shown in FIG. The front view of the coil spring shown in FIG. The explanatory view in the neutral state of the operation part shown in FIG. The explanatory view which shows the state of the operation part at the time of rotating operation of an operation lever from the state shown in FIG. It is a figure explaining the manufacturing process of a pinion shaft, FIG. FIG. 3C is a perspective view showing a bearing portion cutting process.

1 to 13 show a brake device for an automobile seat (hereinafter, simply abbreviated as "seat") according to the present invention and a more specific form for carrying out a method for manufacturing the brake device, and in particular, FIG. 1 shows an example of a seat having a position adjusting structure.

As shown in FIG. 1, the seat 1 has a seat slide mechanism 2 that adjusts the front-rear position of the seat 1, a seat lifter mechanism that adjusts the height position of the seat cushion 3 that serves as a seat surface, and a backrest as so-called position adjustment mechanisms. It is provided with a reclining mechanism for adjusting the angle adjustment of the seat back 4 which is a part. An operation lever 5 of the seat lifter mechanism and an operation lever 6 of the reclining mechanism are provided side by side on the side of the seat cushion 3 for operating each of these mechanisms.

Then, in the seat 1 shown in FIG. 1, when focusing on the seat lifter mechanism, the operation lever 5 of the seat lifter mechanism is referred to as, for example, a neutral position (in the following description, the state in which the operation lever 5 is in the neutral position is also referred to as a "neutral state". The position of the seat cushion 3 is gradually raised each time the operation lever 5 is pulled upward from the neutral position, while the position of the seat cushion 3 is gradually lowered each time the operation lever 5 is pushed down from the neutral position. It has the structure of. As a result, the height position adjusting function of the seat surface of the seat 1 is exhibited.

(Brake device configuration)
FIG. 2 shows a front view equivalent to the vehicle-mounted state of the brake device 7 applied to the seat lifter mechanism of the seat 1 shown in FIG. 1, and FIG. 3 shows a left side view of FIG. 2, respectively. Further, FIG. 4 shows a left side view of FIG. 3 with the lever bracket 24 and the coil spring 23 removed, and FIG. 5 shows a cross-sectional view taken along the line AA of FIG. Further, FIG. 6 shows an exploded perspective view of the brake device 7 shown in FIG. In the description of each figure, the direction of the rotation axis of the pinion shaft 12 is defined as the "axial direction", and the right side (housing 11 side) of FIG. 6 and the side close to the seat (not shown) is "inward in the axial direction". , The left side (lever bracket 24 side) of FIG. 6 and the side separated from the seat (not shown) will be described as "axially outside".

In addition to FIG. 2, as shown in the exploded perspective view of FIG. 6, in the brake device 7, a substantially cylindrical case is formed by abutting the housing 11 which is a half-split housing member and the cover 22 which is a cover member. 8 is formed. In this case 8, the brake unit 9 and a part of the components of the operation unit 10, which will be described later, are coaxially housed. Further, a pinion shaft 12 substantially shared by the brake portion 9 and the operation portion 10 penetrates in the axial direction in the central portion of the housing 11 and the cover 22 forming the case 8. Is placed. A lever bracket 24 that functions as an operating member together with the operating lever 5 shown in FIG. 1 is rotatably supported at one end of the pinion shaft 12, and a pinion gear 12g exposed to the outside is integrated at the other end of the pinion shaft 12. Is formed in.

The lever bracket 24 can be rotated from the neutral position in either the forward rotation direction or the reverse rotation direction. Further, the operating lever 5 shown in FIG. 1 is screwed and fixed to the lever bracket 24 by using the screw hole 24e (see FIG. 3) on the lever bracket 24 side.

Then, the brake device 7 is fixed to a side bracket (not shown) of the seat 1 shown in FIG. 1 by using a mounting hole 29a formed in the flange portion 29 on the cover 22 side, and the pinion gear 12g of the pinion shaft 12 is attached. It meshes with the driven side gear on the seat lifter mechanism side, which is the driving mechanism of the seat 1 (not shown).

In the brake device 7, when the lever bracket 24 is in the neutral position, the braking state is maintained so that the pinion shaft 12 does not rotate due to the reverse input from the pinion shaft 12 side. On the other hand, when the lever bracket 24 is rotated from the neutral position in either the forward rotation direction or the reverse rotation direction, the braking state of the pinion shaft 12 is released, and the rotation of the pinion shaft 12 accompanying the rotation operation of the lever bracket 24 is performed. Will be tolerated. The rotation of the pinion shaft 12 is converted into the rotational displacement of the driven side gear of the seat lifter mechanism (not shown) via the pinion gear 12g, and further converted into the vertical displacement of the seat cushion 3 of the seat 1 via the link mechanism. Will be done.

In this type of brake device 7, since the stroke of the lever bracket 24 is relatively small, in many cases, the intended purpose is achieved by repeating the rotation operation of the lever bracket 24 in a specific direction a plurality of times. Can be achieved.

As shown in FIGS. 2 and 6, inside the case 8 formed by the housing 11 on the brake portion 9 side and the cover 22 on the operation portion 10 side, the brake portion 9 and a part of the components of the operation portion 10 are formed. Are adjacent to each other so that they are located coaxially with each other, as described above. In the following description, the structure will be described centering on FIG. 6 in which the three-dimensional shape and arrangement of each component are relatively easy to understand, and figures other than FIG. 6 will be referred to as appropriate as necessary. ..

As shown in FIG. 6, there are two brake portions, a housing 11 that functions as a part of the case 8, a pinion shaft 12 that is rotatably supported by the housing 11, and two that are arranged to face each other inside the housing 11. A set of substantially semicircular lock plates 14, a lock spring 15 shared by these sets of lock plates 14, and a set of lock plates 14 stacked on the outside in the axial direction inside the housing 11 as well. Another set of lock plates 16 having the same shape, a lock spring 17 shared by the set of lock plates 16, and a shallow set of lock plates 16 are arranged so as to be overlapped on the outer side in the axial direction. A dish-shaped drive wheel 18 is provided.

The operation unit 10 has a leaf spring-shaped holding plate 19 which is arranged so as to be overlapped on the outer side in the axial direction of the drive wheel 18, a tooth plate 20 which is combined with the holding plate 19, and an input which is overlapped with the holding plate 19 and the tooth plate 20. The cover 22 that forms the case 8 by being abutted against the lever 21 and the housing 11 on the brake portion 9 side, the coil spring 23 that is a torsion coil spring arranged on the axially outer side of the cover 22, and the cover 22 as well. A lever bracket 24 as an operating member arranged on the outer side in the axial direction of the above is provided.

The housing 11 of the brake portion 9 shown in FIG. 6 is, for example, squeezed and press-molded into a substantially deep dish shape using a sheet metal material having a predetermined thickness, and the inner peripheral surface of the housing 11 is a cylindrical braking surface 13. It has become.

Further, a shaft hole 11a into which the large diameter shaft portion 12f on the pinion gear 12g side of the pinion shaft 12 is inserted is formed through the bottom portion of the housing 11 along the axial direction. Further, three flange portions 11b extending radially outward are formed at the opening edge portion of the housing 11, and a locking recess 11c having a central portion recessed is formed at the tip portion of each flange portion 11b. Will be done. These locking recesses 11c serve as coupling fixing portions with the cover 22 described later.

The pinion shaft 12 of the brake portion 9 shown in FIGS. 6 and 8 includes a small diameter shaft portion 12a, a medium diameter shaft portion 12b, and a substantially rectangular shaft-shaped deformed shaft portion 12c having a pair of width across flat portions 121d and 122d. , As shown in FIG. 5, are rotatably supported by a pair of restricting portions 121e and 122e that abut on the inner bottom surface of the housing 11 and restrict the axial movement of the pinion shaft 12, and the shaft hole 11a of the housing 11. A so-called multi-stage stepped shaft shape in which a large-diameter shaft portion 12f as a bearing portion, a pinion gear 12g as a drive side gear, and a tip shaft portion 12h provided at the tip portion of the pinion gear 12g are coaxially formed. It is a thing. The pinion shaft 12 is shared by the brake unit 9 and the operation unit 10 as described later.

As shown in FIGS. 6 and 8, the deformed shaft portion 12c of the pinion shaft 12 includes a pair of width across flat portions 121d and 122d arranged so as to face each other substantially in parallel with the rotation center Z of the pinion shaft 12 interposed therebetween. It has a substantially oval cross section having a pair of two-sided width connecting portions connecting the ends of the two-sided width portions 121d and 122d, and a pair of the two-sided width connecting portions projecting outward in the radial direction. A pair of arcuate portions 121c and 122c having the rotation center Z of the pinion shaft 12 as the center of curvature are provided in a portion having the restricting portions 121e and 122e and not having the pair of restricting portions 121e and 122e in the axial direction. The deformed shaft portion 12c (a pair of arcuate portions 121c, 122c) and the large diameter shaft portion 12f have substantially the same outer diameter, and form the maximum diameter of the pinion shaft 12 as a whole. Further, the width across flat portions 121d and 122d of the deformed shaft portion 12c function as acting portions that exert an external force on the two sets of lock plates 14 and 16.

The pair of restricting portions 121e and 122e of the pinion shaft 12 are arranged at symmetrical positions with respect to the rotation center Z of the pinion shaft 12 at the intermediate portion in the circumferential direction of the pair of arcuate portions 121c and 122c of the deformed shaft portion 12c. It is formed in a flat shape (plate shape) extending along the radial direction. Further, the pair of restricting portions 121e and 122e are provided so as to be biased toward the large-diameter shaft portion 12f in the axial direction, and due to such a biased arrangement, the arc-shaped portions 121c and 122c remaining on the medium-diameter shaft portion 12b side. In addition, the drive wheel 18 described later can be engaged.

Then, the pair of flattening regulating portions 121e and 122e are in a direction orthogonal to the axial direction of the pinion shaft 12, and are in a part of the axial region of the pair of widthwise connecting portions of the deformed shaft portion 12c. Both ends in the width direction of the two-sided width portions 121d and 122d are integrally formed by pressing and plastically deforming them so as to sandwich them in the thickness direction of the two-sided width portions 121d and 122d. That is, in the pair of restricting portions 121e and 122e, both end portions in the circumferential direction are crushed in a part of the axial region of the pair of two-sided width connecting portions, and the intermediate portion protrudes outward in the radial direction. By plastically flowing, it is formed so as to project radially outward from the pair of arcuate portions 121c and 122c.

Further, the pair of restricting portions 121e and 122e of the pinion shaft 12 each have a pair of substantially flat axial side surfaces that are substantially parallel to each other, and are set to a substantially constant thickness in the extending direction (diameter direction). Has been done. Further, both end faces in the axial direction of the pair of restricting portions 121e and 122e also exhibit substantially parallel flat shapes, and the end faces on the large-diameter shaft portion 12f side abut on the inner bottom surface of the housing 11, so that the pinion shaft 12 Movement to the outside (seat side) in the axial direction is restricted.

The set of lock plates 14 of the brake portion 9 shown in FIG. 6 are arranged symmetrically or vertically symmetrically so that the outer peripheral surfaces of both ends are in contact with the braking surface 13 while being seated on the inner bottom surface of the housing 11. Further, another set of lock plates 16 is placed on the set of lock plates 14 so as to be symmetrical or vertically symmetrical so as to be overlapped and opposed to each other in the axial direction of the pinion shaft 12. Of the outer peripheral surfaces of these two sets of lock plates 14 and 16, arc-shaped braking lock surfaces 26 that can contact the braking surfaces 13 of the housing 11 are formed at both ends separated by the recess 25. ..

A lock spring 15 as an urging means is interposed between both end portions (first end portions) of the set of lock plates 14. That is, the lock spring 15 urges one end portions (first end portions) of the set of lock plates 14 in a direction in which they are separated from each other. Similarly, in the other set of lock plates 16, a lock spring 17 as an urging means is interposed between both end portions (second end portions). That is, the lock spring 17 urges one end portion (second end portion) of the set of lock plates 16 in a direction in which they are separated from each other.

The lock springs 15 and 17 shown in FIG. 6 are formed by bending the leaf springs 15a and 17a in a substantially M shape, respectively, and coil springs 15b between the ends of the legs of both the leaf springs 15a and 17a. , 17b is sandwiched between them, which is a so-called composite spring type. As shown in FIG. 7, the recesses 15c and 17c of the leaf springs 15a and 17a formed in a substantially M shape are fitted into the pair of restricting portions 121e and 122e of the pinion shaft 12, respectively, thereby regulating the pair of regulation portions 121e and 122e, respectively. It is supported by the pinion shaft 12 via the portions 121e and 122e. The coil springs 15b and 17b are urged in the direction in which both legs of the leaf springs 15a and 17a are widened, respectively.

The drive wheel 18 of the brake portion 9 shown in FIG. 6 has a so-called internal gear shape in which internal teeth 18b are formed on the inner peripheral surface of the ring portion 18a on the outer peripheral side over the entire circumference thereof. A square hole 18c is formed in the central portion of the drive wheel 18 so that the deformed shaft portion 12c of the pinion shaft 12 can be integrally rotated. Further, on the back surface side of the drive wheel 18, a pair of arc-shaped release claws 18d projecting toward the two sets of lock plates 14 and 16 are integrally formed (see FIG. 7).

It should be noted that there is a predetermined play in the rotation direction between the square hole 18c of the drive wheel 18 and the deformed shaft portion 12c of the pinion shaft 12. Further, in the drive wheel 18, for example, a metal disk is half-cut by press molding to form a ring portion 18a having internal teeth 18b (see FIG. 5), and the inner bottom portion and the release claw portion 18d of the ring portion 18a are formed. Is integrally formed of a resin material by a method such as a so-called insert molding method.

In the brake portion 9 configured in this way, as shown in FIG. 5, the pinion shaft 12 shown in FIG. 6 has a large-diameter shaft portion 12f formed at the base of the pinion gear 12g, and the shaft hole 11a of the housing 11 is formed. Rotatably inserted and supported. On the other hand, the width across flats 12d of the deformed shaft portion 12c are inserted so as to be located in the opposing gaps between the set of lock plates 14 and the other set of lock plates 16. Further, the deformed shaft portion 12c is loosely fitted into the square hole 18c of the drive wheel 18 and rotatably fitted by a minute angle.

At that time, as shown in FIG. 7, a pair of release claws 18d on the drive wheel 18 side are pinions on the outer peripheral sides of the two sets of lock plates 14 and 16 in the recesses 25 of the lock plates 14 and 16, respectively. It is fitted with a gap in the rotation direction of the shaft 12. The arcuate outer peripheral surfaces of the pair of release claws 18d are pressed against the braking surface 13 of the housing 11 by the elastic force of each release claw 18d itself.

FIG. 7 is an explanatory view of the brake portion 9 shown in FIG. 6 in a neutral state. As shown in FIG. 7, of the opposing end faces P of the pair of lock plates 16 located on both sides of the deformed shaft portion 12c of the pinion shaft 12, the portion facing the width across flats 12d of the deformed shaft portion 12c. Is formed with arcuate convex portions 16a and 16b at positions corresponding to two positions on the left and right of the rotation center of the deformed shaft portion 12c. A lock spring 17 is interposed between one end (second end) of the set of lock plates 16, and the one ends (second end) are urged so as to be separated from each other. Has been done.

Therefore, the set of lock plates 16 rotationally moves along the braking surface 13 of the housing 11 by a predetermined amount, whereby the distance between the first ends of the lock plates 16 is larger than the distance between the second ends of the lock plates 16. The one is smaller. As a result, of the pair of convex portions 16a and 16b formed on the opposite end surfaces P of the set of lock plates 16, one of the convex portions 16b is on one side of the width across flat portion 12d of the deformed shaft portion 12c. The other convex portion 16a is in contact with the deformed shaft portion 12c and is separated from the width across flat portion 12d.

These relationships are the same for the other set of lock plates 14 shown in FIG. 6, and the lock spring 15 is interposed between one end (first end) of the set of lock plates 14. Therefore, one end portion (first end portion) thereof is urged so as to be separated from each other. Therefore, as will be described later, the width across flats portion 12d that functions as the acting portion of the deformed shaft portion 12c comes into contact with the two sets of lock plates 14 and 16 without a gap in the rotational direction.

In each of the drawings after FIG. 7, the orientations of the components of the brake unit 9 and the operation unit 10 are drawn so as to be 90 degrees different from the orientation of FIG. Further, the two-sided width portions 121d and 122d of the pinion shaft 12 shown in FIG. 7 are drawn as tapered surfaces inclined toward both upper and lower ends with the central portion in the vertical direction in the figure as the top, but the two-sided width portion 121d. , 122d may be a simple flat surface with no inclination.

The holding plate 19 of the operation unit 10 shown in FIG. 6 has a leaf spring shape that exhibits spring characteristics in the axial direction of the pinion shaft 12. The holding plate 19 extends radially from the boss portion 19a in which the shaft hole 19b to be inserted into the medium-diameter shaft portion 12b of the pinion shaft 12 is formed, and is formed by being integrally bent toward the drive wheel 18 side. A pair of leg portions 19c that are seated on the bottom portion of the drive wheel 18 and an arm portion 19d that also extends radially from the boss portion 19a and is integrally bent in a stepped shape are provided. The arm portion 19d is formed with a first shaft portion 19e that functions as a first support portion and is rounded into a substantially cylindrical shape with the tip cut up.

Further, on the holding plate 19, a pair of working pieces 19f extending in the radial direction so as not to interfere with the arm portion 19d on the arm portion 19d side are formed by bending toward the cover 22 side. Then, a locking portion 19g is curvedly formed at the tip of each of these working pieces 19f. Further, the holding pieces 19h as the pair of holding parts are formed so as to sandwich the arm portion 19d inside the pair of working pieces 19f so as to project straight in the radial direction.

The tooth plate 20 shown in FIG. 6 has a substantially semicircular arc shape and is arranged in the drive wheel 18 so as to be stacked on the arm portion 19d of the holding plate 19 from the outside in the axial direction. At the center of the tooth plate 20, a deformed shaft portion 20a is formed so as to project toward the cover 22 side, and is circular at a position offset outward from the shaft portion 20a in the radial direction centered on the pinion shaft 12. The shaft hole 20b is formed through. Further, rim portions 20c are formed at both ends of the tooth plate 20 so as to face the internal teeth 18b on the drive wheel 18 side. External teeth 20d that mesh with the internal teeth 18b on the drive wheel 18 side are formed on the outer peripheral surface of the rim portion 20c.

A part of the shaft portion 20a is cut out and formed in a substantially D shape. This is to avoid interference with the adjacent shaft hole 20b, and if such interference can be avoided. For example, the shaft portion 20a may have a cylindrical shaft shape.

The input lever 21 shown in FIG. 6 functions as an input member in the operation unit 10. As shown in FIGS. 6 and 9, the input lever 21 is bent so as to project from the substantially plate-shaped lever body 21d provided in the central portion and the outer peripheral edge portion of the lever body 21d toward the cover 22 side. It has three bent locking pieces 21c formed. A shaft hole 21a rotatably supported by the medium-diameter shaft portion 12b of the pinion shaft 12 is formed in the central portion of the lever body 21d. Further, the lever body 21d is formed with a small-diameter shaft hole 21b as a second support portion through which the shaft portion 20a of the tooth plate 20 is inserted at a position offset radially outward from the shaft hole 21a. As shown in FIG. 9, the three bent locking pieces 21c are each formed in an arc shape that curves along the circumferential direction, and the connection base 21e connected to the lever body 21d and the tip end portion of the connection base 21e. A pair of tip split pieces 21f that are bifurcated and engage with a square hole 24f of a lever bracket 24, which will be described later, are integrally provided. Further, of the three bending locking pieces 21c, at least two bending locking pieces have a predetermined width with a predetermined radius along the circumferential direction so that the outer peripheral side thereof is located inside the winding portion of the coil spring 23. It is formed in an arc shape so as to have. When the input lever 21 is in the neutral position, the two bending locking pieces located inside the winding portion of the coil spring 23 are in the normal rotation direction of the input lever 21 with respect to the cut-up piece 22e of the cover 22 described later. It is arranged at a circumferential position shifted by 90 ° in the reverse direction. Further, each of the connection bases 21e of the bent locking pieces 21c is formed with chamfer-shaped relief portions 21g along the extending direction of the connection bases 21e on the outer peripheral side edges of both ends in the circumferential direction. The relief portion 21g may be an inclined flat surface formed in a so-called C chamfered shape, or may be an arc-shaped curved surface formed in a so-called R chamfered shape.

Then, the shaft portion 20a of the tooth plate 20 is rotatably inserted and supported with respect to the small diameter shaft hole 21b of the input lever 21. As a result, the input lever 21 and the tooth plate 20 are connected so as to be relatively rotatable. Further, the shaft hole 20b of the tooth plate 20 engages with the first shaft portion 19e of the holding plate 19, and the tooth plate 20 and the holding plate 19 are connected so as to be relatively rotatable. In this case, the tooth plate 20 is sandwiched between the arm portion 19d of the holding plate 19 and the holding piece 19h. The relationship between the shaft hole 20b of the tooth plate 20 and the shaft and hole of the first shaft portion 19e of the holding plate 19 may be reversed.

The cover 22 shown in FIG. 6 is integrally molded into a bottomed cylindrical shape having a substantially cup shape by, for example, deep drawing by pressing. As shown in FIGS. 2 and 5, the cover 22 is abutted against the housing 11 on the brake portion 9 side to form the case 8 of the brake device 7 together with the housing 11. Then, as described above, a part of the components of the brake unit 9 and the operation unit 10 are housed and arranged inside the case 8.

In this case, as shown in FIG. 5, the holding plate 19 is sandwiched between the drive wheel 18 and the input lever 21 and is bent and deformed, so that the holding plate 19 is pressed against both of them. Further, the end portion of the leg portion 19c of the holding plate 19 is pressed against the resin-molded portion of the bottom wall portion of the drive wheel 18, so that the holding plate 19 slides at least with the drive wheel 18 in the relative rotation direction. Gives dynamic resistance.

As shown in FIG. 4, two sets of arcuate elongated holes 22b are formed on the bottom wall portion of the cover 22 at positions facing each other with the shaft hole 22a in between, together with the shaft hole 22a in the central portion. An opening is formed. Further, in the direction orthogonal to the opposite direction of the pair of elongated holes 22b, an opening 22c made of an arcuate elongated hole is formed on one side, and the opening is formed together with the rectangular opening 22d on the other side. The cut-up piece 22e as the cover-side protruding portion cut up with the formation of the portion 22d is formed to have a predetermined width in the circumferential direction so as to stand upright outward in the axial direction. The length of the opening 22c (perimeter of the arc) is set to be larger than the length of the set of elongated holes 22b (perimeter of the arc). Then, when the cover 22 is abutted against the housing 11 on the brake portion 9 side, the shaft hole 22a is fitted into the small diameter shaft portion 12a of the pinion shaft 12, so that the pinion shaft 12 can be rotated by the housing 11 and the cover 22. It is supported by both sides.

As shown in FIG. 4, three bending locking pieces 21c on the input lever 21 side are inserted into a pair of elongated holes 22b and an opening 22c so as to project toward the lever bracket 24 side. Will be done. Here, the length (perimeter) of the set of elongated holes 22b and the opening 22c is set sufficiently larger than the width dimension of the three bent locking pieces 21c. As a result, the rotation range of the input lever 21 that can rotate in the forward and reverse directions, and by extension, the rotation range of the lever bracket 24 that is coupled to the input lever 21 is within the length range of the set of elongated holes 22b. Be regulated. That is, the inner surfaces of both ends in the longitudinal direction (both ends in the circumferential direction) of the set of elongated holes 22b function as stopper surfaces that regulate the rotation range of the lever bracket 24.

Further, as shown in FIG. 4, in a state where the input lever 21 is in the neutral position as shown in the figure, the opening 22c of the cover 22 has both ends in the longitudinal direction (both ends in the circumferential direction) in FIG. The locking portions 19g of the working piece 19f of the holding plate 19 shown are respectively engaged and disengaged. As a result, the holding plate 19 is rotationally displaced together with the input lever 21 via the tooth plate 20, and when the input lever 21 returns to the neutral position, the holding plate 19 also returns to the neutral position accordingly.

Further, as shown in FIG. 4, guide protrusions 27 are formed by bending each of the outer peripheral edges of the set of elongated holes 22b toward the inside in the axial direction. As shown in FIGS. 5 and 11, these guide protrusions 27 face the internal space of the brake portion 9, respectively, and serve to guide the movement of the tooth plate 20 as described later.

Further, at the opening edge portion of the cover 22 shown in FIGS. 4 and 6 on the side facing the housing 11, flange portions 29 having mounting holes 29a are provided at three locations in the circumferential direction toward the outer side in the radial direction, for example. It is bent and formed. Further, locking flange portions 30 having a protrusion length smaller than that of the flange portions 29 are projected and formed at three locations in the circumferential direction that do not interfere with each flange portion 29. As shown in FIG. 2, these locking flange portions 30 are fitted into the locking recess 11c on the housing 11 side when the housing 11 and the cover 22 are butted against each other in order to form the case 8. .. Then, as shown in FIG. 2, the housing 11 and the cover 22 are integrally coupled and fixed by caulking both side surface portions of the locking flange portion 30 in the axial direction. The flange portion 29 of the cover 22 serves as an attachment portion of the brake device 7 to the seat 1 shown in FIG.

As shown in FIG. 5, the lever bracket 24 shown in FIG. 6 is drawn and press-molded into a bottomed cylindrical shape having a substantially shallow dish shape, and is arranged outside the bottom wall portion of the cover 22 in the axial direction. NS. A coil spring 23 is arranged between the cover 22 and the lever bracket 24 so as to be accommodated in the concave space of the lever bracket 24. A shaft hole 24a penetrating along the axial direction is formed at the center position of the bottom wall portion of the lever bracket 24. The shaft hole 24a is rotatably supported by the small diameter shaft portion 12a of the pinion shaft 12. Further, as shown in FIG. 3, on the peripheral edge of the bottom wall portion of the lever bracket 24, together with a pair of positioning pieces 24b, the positioning pieces 24b project inward in the axial direction toward the cover 22 side between the positioning pieces 24b. A cut-up piece 24c is formed as a protrusion on the bracket side.

Further, as shown in FIG. 3, the lever bracket 24 shown in FIG. 6 is formed with a pair of flange portions 24d having screw holes 24e on the outer peripheral side, and the outer peripheral region of the shaft hole 24a in the bottom wall portion. A square hole 24f corresponding to a pair of bifurcated tip split pieces 21f of the three bending locking pieces 21c on the input lever 21 side is formed. From such a configuration, the three bent locking pieces 21c insert the pair of elongated holes 22b and the opening 22c of the cover 22 and then engage with the square holes 24f of the lever bracket 24 while engaging with the pair of tip split pieces 21f. Becomes a prominent form.

Then, as shown in FIG. 3, by bending the pair of tip split pieces 21f in each of the bent locking pieces 21c protruding from the square hole 24f in the direction of separating from each other, the lever bracket 24 is input in the form of sandwiching the cover 22. The lever 21 and the lever 21 are fixed to each other. As a result, the relative rotation between the lever bracket 24 and the input lever 21 is prevented, and the lever bracket 24 can rotate integrally with the input lever 21 in the forward rotation direction and the reverse rotation direction.

Further, the cut-up piece 24c formed on the lever bracket 24 is arranged inside the cut-up piece 22e of the cover 22 in the radial direction and is set to have the same width at the same position in the circumferential direction. There is. With this configuration, as shown in FIGS. 3 and 4, when the lever bracket 24 and the input lever 21 are fixed with the cover 22 sandwiched between them, both cut-up pieces 22e and 24c overlap each other in the axial direction. Become.

Further, the operating lever 5 shown in FIG. 1 is attached to the lever bracket 24 shown in FIGS. 3 and 6. The operating lever 5 is relatively positioned using a pair of positioning pieces 24b of the lever bracket 24, and then fixed to the lever bracket 24 by two screw holes 24e and a set screw (not shown). As a result, the lever bracket 24 functions as an operating member in the operating unit 10 together with the operating lever 5.

As shown in FIG. 10, the coil spring 23 shown in FIG. 6 is housed between the cover 22 and the lever bracket 24, and has a function of holding the input lever 21 together with the lever bracket 24 in a neutral position. Have. The coil spring 23 includes a winding portion 23a that is doubly wound in a coil shape, and a pair of first hook portions 23b that are formed by bending both ends of the winding portion 23a in the circumferential direction outward in the radial direction. The first hook portion 23b has a pair of second hook portions 23c formed by bending the tip portions of the first hook portions 23b outward in the circumferential direction (so as to fold back toward the winding portion).

As shown in FIG. 10, the winding portion 23a and the first winding portion 231a of the first lap having a ring shape, which are wound in double (two turns) so as to partially overlap in the axial direction. It is composed of a second winding portion 232a on the second lap. More specifically, the winding portions 231a and 232a are free when viewed from the free end side semicircle having the first hook portion 23b and the connecting side semicircle connected to the other winding portion, respectively. In the state, as shown in FIG. 10, the free end portion of the first winding portion 231a and the free end portion of the second winding portion 232a do not overlap, and the free end side half of one winding portion. The distance L1 from the rotation center Z of the input lever 21 in the circumferential middle portion of the circular portion is from the distance L2 from the rotation center Z of the input lever 21 in the circumferential intermediate portion of the connecting side semicircle of the other winding portion. Is also formed to be large. In other words, in the free state, the center Q1 of the first winding portion 231a and the center Q2 of the second winding portion 232a do not coincide with each other in the first winding portion 231a and the second winding portion 232a. It is configured to be offset from each other in the radial direction. At this time, the first winding portion 231a and the second winding portion 232a are located at a substantially intermediate portion of the free end side semicircle portion having the first hook portion 23b, and the distance L1 from the rotation center Z of the lever 21 is 1. L2 is the maximum. The deviation amount X of the distances L1 and L2 from the rotation center Z of the lever 21 of the first winding portion 231a and the second winding portion 232a is the line of the first and second winding portions 231a and 232a at the maximum. It is about the diameter (diameter). On the other hand, in the assembled state, the winding portion 23a is in a state where the free end portion of the first winding portion 231a and the free end portion of the second winding portion 232a overlap each other, and the winding portion 23a is rotated so as to maintain this overlapping state. A cut-up piece 22e as a cover-side protruding portion having a predetermined width in the direction engages between the first hook portions 23b. In this assembled state, the free end side semicircle portion of one winding portion and the connecting side semicircle portion of the other winding portion are at a distance L1 from the rotation center Z of the input lever 21 in the circumferential intermediate portion thereof. , L2 are set to be the same and overlap. In other words, in the assembled state, when the input lever 21 is in the neutral position, the center Q1 of the first winding portion 231a and the center Q2 of the second winding portion 232a substantially coincide with each other in the radial direction. The first winding portion 231a and the second winding portion 232a are configured to be substantially completely overlapped with each other.

As shown in FIG. 10, the pair of first hook portions 23b and 23b are formed by bending the winding portion 23a substantially perpendicularly outward in the radial direction so as to extend along the radial direction of the winding portion 23a. It is formed so as to be substantially parallel in the assembled state, and as will be described later, a cut-up piece of a cover 22 having the same width in the circumferential direction between the pair of first hook portions 23b and 23b. The cut-up piece 24c of the 22e and the lever bracket 24 can be locked in the circumferential direction.

As shown in FIG. 10, the second hook portion 23c folds the tip end portion of the first hook portion 23b toward the winding portions 231a and 232a in opposite directions to the outside in the circumferential direction of the winding portions 231a and 232a, respectively. It is bent and formed, and in the assembled state, it can be locked in the radial direction with respect to the cut-up piece 22e of the cover 22, as will be described later. That is, by locking the second hook portion 23c to the outer surface (diameter outer surface) of the cut-up piece 22e of the cover 22 on the fixed side, the coil spring 23 can move in the radial direction through the cut-up piece 22e. It is becoming regulated.

As shown in FIG. 3, the coil spring 23 configured in this way has a pair of hook portions 23b arranged so as to face each other so as to overlap each other in the radial direction after the winding portion 23a is wound and tightened. The cut-up pieces 22e and 24c are locked to the cut-up pieces 22e and 24c so as to sandwich the cut-up pieces 22e and 24c from both sides in the circumferential direction. As a result, regardless of whether the operating lever 5 shown in FIG. 1 is rotated in either the forward rotation direction or the reverse rotation direction, by releasing the operating force, the input lever 21 is moved to the lever bracket by the urging force of the coil spring 23. It will return to the neutral position together with the 24 and the operating lever 5.

(Brake device function)
The functions of the brake device 7 configured as described above are as follows.

Unless the operating lever 5 shown in FIG. 1 is rotated together with the lever bracket 24 shown in FIGS. 3 and 6, the lever bracket 24 is held in a neutral state together with the input lever 21 by the urging force of the coil spring 23.

In the neutral state shown in FIGS. 3 and 11, the tooth plate 20 in the operation unit 10 is also in the neutral state, and the outer teeth 20d on both sides of the tooth plate 20 both have a gap with respect to the inner teeth 18b of the drive wheel 18. It is in a non-meshing state facing each other. At the same time, as shown in FIG. 7, in the brake portion 9, one convex portion 16a, 16b of each of the two sets of lock plates 14, 16 urged by the lock springs 15 and 17, respectively, is the two surfaces of the pinion shaft 12. The width portions 121d and 122d are in pressure contact with each other, and the braking lock surfaces 26 at both ends are in pressure contact with the braking surface 13 of the housing 11. As a result, the pinion shaft 12 is prevented from rotating in both the forward rotation direction and the reverse rotation direction, and has the frictional force of both (the braking lock surface 26 of the lock plates 14 and 16 and the braking surface 13 of the housing 11). It is self-holding the braking state.

In this case, even if the reverse input to the brake device 7 from the seat lifter mechanism side due to the seating of the occupant acts, the braking surface 13 of the housing 11 and the braking lock surface 26 of the two sets of lock plates 14 and 16 act. The braking state can be self-held by the frictional force. As described above, in the brake portion 9, the braking surface 13 of the housing 11 and the two sets of lock plates 14 and 16 including the lock springs 15 and 17 function as direct braking elements.

On the other hand, in order to release the braking state of the brake unit 9 in the brake device 7 when adjusting the height position by the seat lifter mechanism described above, the lever bracket 24 of the operation unit 10 shown in FIG. 6 is shown in FIG. It shall be rotated in the forward rotation direction or the reverse rotation direction together with the operation lever 5.

As described above, FIG. 11 shows the neutral state of the operation unit 10 in the brake device 7. In the state of FIG. 11, the outer teeth 20d at both ends of the tooth plate 20 face each other with a gap with respect to the inner teeth 18b of the drive wheel 18 in a non-meshing state. The rim portion 20c of the tooth plate 20 on which the outer teeth 20d are formed is separated from the guide protrusion 27 formed so as to protrude from the cover 22.

It is assumed that the lever bracket 24 is rotated together with the operation lever 5 from the neutral state of the operation unit 10 shown in FIG. 11 in either the forward rotation direction or the reverse rotation direction, for example, in the clockwise direction from the state of FIG. Try. As the lever bracket 24 rotates in the clockwise direction, the input lever 21 of the operation unit 10 also rotates integrally in the same direction. Further, the tooth plate 20 is also pushed in the clockwise direction by fitting the shaft portion 20a to the small diameter shaft hole 21b on the input lever 21 side.

The tooth plate 20 is supported by the first shaft portion 19e of the holding plate 19 by the shaft hole 20b, and the holding plate 19 has rotational resistance due to pressure contact with the inner bottom surface of the drive wheel 18 with respect to rotation in the clockwise direction. ing. Therefore, the tooth plate 20 rotates in the counterclockwise direction in the drawing about the first shaft portion 19e. As a result, as shown in FIG. 11, the outer teeth 20d of the upper rim portion 20c of the tooth plate 20 mesh with the inner teeth 18b of the drive wheel 18. Then, by further rotating the input lever 21 in the clockwise direction in the drawing from this state, the input lever 21, the tooth plate 20, the holding plate 19, and the drive wheel 18 are integrally rotated. .. FIG. 12 shows a state in which the lever bracket 24 is rotated in the clockwise direction together with the operating lever 5 from the state of FIG.

As shown in FIG. 12, when the input lever 21 is rotated from the neutral position, one of the guide protrusions 27 is positioned so as to face the inner peripheral side of the upper rim portion 20c. Therefore, even if the lower outer tooth 20d of the tooth plate 20 tries to mesh with the inner tooth 18b on the drive wheel 18 side, the lower outer side is caused by the interference between the upper rim portion 20c and the upper guide protrusion 27. The meshing of the tooth 20d and the internal tooth 18b is prevented. Therefore, when the input lever 21 is returned to the neutral position from the state shown in FIG. 12, the input lever 21, the tooth plate 20, and the holding plate 19 are maintained while the lower outer teeth 20d do not mesh with the inner teeth 18b. Will rotate together to a neutral state.

The drive wheel 18 pushed by the engagement with the tooth plate 20 first releases the rotation restriction of the pinion shaft 12 by the two sets of lock plates 14 and 16. Here, as shown in FIG. 7, as the drive wheel 18 rotates in the clockwise direction, the release claw portion 18d rotates the lock plates 14 and 16 in the same direction. As a result, the sandwiching of the width across flats 12d of the pinion shaft 12 by the two sets of lock plates 14 and 16 is released, and the braking state of the brake unit 9 up to that point is substantially released. By releasing this braking state, the pinion shaft 12 can rotate with respect to the housing 11 together with the two sets of lock plates 14 and 16.

Next, the rotation of the pinion shaft 12 by the drive wheel 18 pushed by the tooth plate 20 is provided between the square hole 18c shown in FIG. 6 and the width across flats 12d of the deformed shaft portion 12c on the pinion shaft 12 side. It is performed after rotating by a predetermined amount of play. The pinion shaft 12 is rotated in the clockwise direction of FIG. 7 when the square hole 18c and the width across flat portion 12d of the deformed shaft portion 12c come into contact with each other. The rotation of the pinion shaft 12 is nothing but the rotation of the pinion gear 12g shown in FIG. 6, and the rotation of the pinion gear 12g causes the driven side gear of the seat shifter mechanism (not shown) that meshes with the pinion gear 12g to rotate, so that the seat 1 The height position will be displaced to the lower side, for example.

As is clear from the above description, since the amount of vertical displacement of the seat 1 in FIG. 1 based on the function of the seat lifter mechanism is small for the amount of rotational operation of the operating lever 5, in many cases, the operation is performed. The rotation operation of the lever 5 is repeated a plurality of times.

Here, when the operating force of the operating lever 5 is released, the return force of the coil spring 23 causes the operating lever 5, the input lever 21 of the operating unit 10, the holding plate 19, and the tooth plate 20 to be in the state shown in FIG. The rotation returns to the initial state, which is the neutral position shown in FIG.

When the input lever 21 rotates in the counterclockwise direction from the state shown in FIG. 11 when the rotation returns to the initial state, the tooth plate 20 rotates clockwise around the first shaft portion 19e on the holding plate 19 side. Rotate in the direction.

At this time, the upper guide protrusion 27 on the cover 22 side restricts the upper rim portion 20c from rotating above the neutral position. Therefore, both the upper and lower outer teeth 20d do not mesh with the inner teeth 18b, the drive wheel 18 is left in the previously rotated position, and the drive wheel 18 and the pinion shaft 12 are not rotated. The tooth plate 20 and the holding plate 19 rotate back to the initial state shown in FIG. Then, as shown in FIG. 11, when the tooth plate 20 returns to the initial state, the upper rim portion 20c is released from the restraint by one guide protrusion 27 on the cover 22 side, and both the upper and lower sides of the tooth plate 20 are released. The outer teeth 20d of the above are both in a state where they can mesh with the inner teeth 18b of the drive wheel 18.

Further, as is clear from a comparison between FIGS. 11 and 12, when the holding plate 19 is rotated in the clockwise direction as shown in FIG. 12, the holding piece 19h at the tip of one working piece 19f is attached to the cover 22. It will come out of the opening 22c once. On the other hand, when the holding plate 19 returns to the neutral position as shown in FIG. 11, the holding piece 19h at the tip of one working piece 19f reengages with the opening 22c of the cover 22 and returns to the original state. Return.

As is clear from FIGS. 7 and 11, both the brake unit 9 and the operation unit 10 have an arrangement configuration in which the internal structures are symmetrical or vertically symmetrical. Therefore, in the series of operations as described above, even when the operation lever 5 is rotated in the direction opposite to the above (counterclockwise direction in FIGS. 11 and 12), the operation unit 10 and the brake unit 9 are operated. Only the rotation direction of the rotating element is reversed, and the same operation as described above is performed.

(Manufacturing method of brake device)
Hereinafter, a method for manufacturing the brake device 7 according to the present embodiment, which is particularly characteristic in the present invention, will be described with reference to FIG. 13. 13A and 13B are views for explaining the manufacturing process of the pinion shaft 12, where FIG. 13A is a perspective view showing a pinion gear forming step and a deformed shaft portion forming step, and FIG. 13B is a pinion shaft 12 showing a regulating portion forming step. A cross-sectional view of the deformed shaft portion 12c of the above, (c) is a perspective view showing a bearing portion cutting process.

First, as shown in FIG. 13A, a rod-shaped material M having a substantially circular cross section is embedded from both ends to form a deformed shaft portion 12c (deformed shaft portion forming step), and a pinion gear 12g. (Pinion gear forming process). At this time, it is desirable that the deformed shaft portion 12c is formed so that the outer diameters of the pair of arcuate shaft portions 121c and 122c are the same as or slightly larger than the outer diameter of the large diameter shaft portion 12f. In the embodiment, the width across flats 121d and 122d are formed by embedding, so that the outer diameter of the pair of arcuate portions 121c and 122c is formed larger than the outer diameter of the large diameter shaft portion 12f. Further, the deformed shaft portion 12c and the pinion gear 12g may be formed in the same step or may be formed in separate steps. By embedding from both ends of the material M, the large diameter shaft portion 12f located between the deformed shaft portion 12c and the pinion gear 12g collects the pre-filled meat (extra material) generated by the embedding, and is large. The outer diameter of the diameter shaft portion 12f becomes larger than the required outer diameter. Here, in the present specification, the outer diameter of the large-diameter shaft portion is a required outer diameter, and as will be described later, the required outer diameter after processing cut to an appropriate outer diameter. Say that.

Subsequently, as shown in FIG. 13B, both ends in the circumferential direction of the pair of arcuate portions 121c and 122c of the deformed shaft portion 12c formed in the deformed shaft portion forming step are held by the punch PH of the press device. As shown in the drawing, by pressing in the thickness direction of the width across flat portions 121d and 122d to plastically deform them, a pair of flat regulating portions 121e are formed in the circumferential intermediate portions of the pair of arcuate portions 121c and 122c. , 122e is formed (regulatory part forming step).

Finally, as shown in FIG. 13C, the outer peripheral surface of the large-diameter shaft portion 12f, which is a bearing portion, is turned by a tool (cutting tool) T to adjust the outer diameter of the large-diameter shaft portion 12f to an appropriate dimension. By finishing (bearing portion cutting process), the machining of the pinion shaft 12 is completed. That is, the large-diameter shaft portion 12f is provided between the pinion gear 12g and the deformed shaft portion 12c, and is placed on the outer peripheral side of the large-diameter shaft portion 12f through the processing of the deformed shaft portion forming step and the pinion gear forming step. Since it is difficult to stabilize the outer diameter dimension of the large-diameter shaft portion 12f due to the formation of excess wall, by turning the outer peripheral surface of the large-diameter shaft portion 12f, the large-diameter shaft portion 12f can be formed. Finish the outer diameter to the appropriate size. After the bearing portion cutting step, the pinion shaft 12 is subjected to surface hardening treatment such as carburizing quenching and induction hardening.

(Action and effect of this embodiment)
In the brake device 7 according to the present embodiment, the pinion gear of the pinion shaft 12 is formed by bringing the pair of restricting portions 121e and 122e protruding from the outer peripheral portion of the deformed shaft portion 12c of the pinion shaft 12 into contact with the inner bottom surface of the housing 11. Axial movement to the 12g side is restricted. That is, since the pair of restricting portions 121e and 122e as means for preventing the pinion shaft 12 from coming off from the housing 11 are formed so as to protrude on the outer peripheral side of the pair of width across flats connecting portions in the deformed shaft portion 12c, the deformed shaft portion 12c Compared to the conventional brake device in which a flange portion is provided in series with the brake device 7, it is possible to reduce the size of the pinion shaft 12 in the axial direction by the axial dimension of the flange portion. Can contribute to the miniaturization of.

Further, in the present embodiment, the pair of restricting portions 121e and 122e press both ends of the pair of two-sided width connecting portions in the circumferential direction in the thickness direction of the two-sided width portions 121d and 122d to cause plastic deformation. , Is formed in a flat shape extending along the radial direction of the pinion shaft 12. As a result, the pair of regulating portions 121e and 122e can be easily formed, and the outer diameter of the material M of the pinion shaft 12 can be reduced, so that good productivity can be ensured and the production cost can be reduced.

Further, in the present embodiment, the restricting portions 121e and 122e are formed by pressing the arcuate portions 121c and 122c (see FIG. 13) set to have an outer diameter larger than the outer diameter of the large diameter shaft portion 12f. There is. As a result, it is possible to secure a sufficient amount of meat for molding the pair of restricting portions 121e and 122e while securing the flat surface portions facing the lock plates 14 and 16.

Further, in the present embodiment, the pair of restricting portions 121e and 122e are formed unevenly only on the side of the deformed shaft portion 12c facing the lock plates 14 and 16, and are formed in the axial region overlapping the drive wheel 18. Not formed. As a result, the pair of regulating units 121e and 122e can function only to prevent the pinion shaft 12 from coming off without receiving an input from the drive wheel 18. Therefore, even if the regulating portions 121e and 122e have a flat shape as in the present embodiment, it is possible to secure a necessary and sufficient retaining function.

Further, in the present embodiment, the large diameter shaft portion 12f, which is a bearing portion, is set to have substantially the same outer diameter as the tooth tip circle, which is the maximum outer diameter of the pinion gear 12g. Thereby, the cutting amount of the material when forming the pinion gear 12g and the large diameter shaft portion 12f can be minimized, and the yield of the material can be further improved.

Further, in the present embodiment, a pair of lock springs 15 and 17 are configured to be engaged with the pair of restricting portions 121e and 122e, respectively, and each of these lock springs 15 and 17 is formed by the pair of restricting portions 121e and 122e. It has a structure that is supported by. As a result, the lock springs 15 and 17 can be stably held, and the proper operation of the lock plates 14 and 16 by the lock springs 15 and 17 can be ensured.

The pair of regulating parts according to the present invention is not limited to the flat shape as in the above-described embodiment, as long as it can come into contact with the inner bottom surface of the case 8 (housing 11). It can be changed arbitrarily according to the specifications of the applicable brake device. Further, the method of forming the pair of regulatory portions according to the present invention, that is, the regulation portion forming step is not limited to the mode of the above-described embodiment, and any method according to the form of the regulatory portion can be adopted. ..

7 ... Brake device 8 ... Case 9 ... Brake part 10 ... Operation part 11a ... Shaft hole 12 ... Pinion shaft 12c ... Deformed shaft part 121c, 122c ... Pair of arcuate parts 121d, 122d ... Width across flats 121e, 122e ... Pair Regulatory part (pair of protrusions)
12f ... Large diameter shaft (bearing)
12g ... Pinion gear 14, 16 ... Lock plate 15, 17 ... Lock spring (urging means)
15a, 17a ... Leaf springs 15b, 17b ... Coil springs

Claims (6)

A brake unit that includes a pinion shaft linked to a position adjusting mechanism provided on an automobile seat and supports the pinion shaft so as not to rotate against a reverse input from the pinion shaft, and an operation unit for operating the pinion shaft. Are housed and arranged in a substantially cylindrical case so as to be overlapped in the axial direction of the pinion shaft.
The pinion shaft penetrates the case in the axial direction and is rotatably supported by the case, and one end projecting outward in the axial direction from the case rotates an operation lever for operating the operation unit. A brake device for an automobile seat, which supports the case as much as possible and whose other end projecting outward in the axial direction from the case is connected to the position adjusting mechanism.
The pinion axis is
A pinion gear that faces the outside of the case and meshes with a gear provided in the position adjusting mechanism.
A bearing portion that is rotatably supported by a shaft hole formed through the bottom of the case, and a bearing portion.
A deformed shaft portion facing the brake element constituting the brake portion and having a width across flats set to be smaller than the outer diameter of the bearing portion.
Is formed continuously in the axial direction,
In the deformed shaft portion, a pair of two-sided width connecting portions connecting the two-sided width portions project outward in the radial direction of the pinion shaft and abut on the bottom of the case in the axial direction of the pinion shaft. A brake device for an automobile seat, which is characterized by integrally providing a pair of regulation parts that regulate movement. In the automobile seat braking device according to claim 1,
The deformed shaft portion has a substantially oval cross section in which the pair of two-sided width connecting portions have an arc shape.
The pair of restricting portions is composed of a pair of protrusions formed in the circumferential intermediate portion of the pair of two-sided width connecting portions so as to project radially outward from the bearing portion.
The pair of protrusions is flattened to extend along the radial direction of the pinion shaft by pressing the arc-shaped portion of the pair of two-sided width connecting portions in the thickness direction of the two-sided width portion to plastically deform them. A braking device for an automobile seat, which is characterized by being formed in a shape. In the automobile seat braking device according to claim 1 or 2.
The pair of two-sided width connecting portions include a pair of arcuate portions having no pair of restricting portions in the axial direction, and the outer diameter of the arcuate portions is the same as the outer diameter of the bearing portion, or the above. An automobile seat braking device characterized by having an outer diameter slightly larger than that of a bearing portion. In the brake device for an automobile seat according to any one of claims 1 to 3.
The bearing portion is a brake device for an automobile seat, characterized in that the outer diameter is set to substantially the same as the tooth tip circle of the pinion gear. A brake unit that includes a pinion shaft linked to a position adjusting mechanism provided on an automobile seat and supports the pinion shaft so as not to rotate against a reverse input from the pinion shaft, and an operation unit for operating the pinion shaft. Are housed and arranged in a substantially cylindrical case so as to be overlapped in the axial direction of the pinion shaft.
The pinion shaft penetrates the case in the axial direction and is rotatably supported by the case, and one end projecting outward in the axial direction from the case rotates an operation lever for operating the operation unit. It is a method of manufacturing a brake device for an automobile seat, which is capable of supporting and has an other end projecting outward in the axial direction from the case connected to the position adjusting mechanism.
The pinion axis is
A pinion gear that faces the outside of the case and meshes with a gear provided in the position adjusting mechanism.
A bearing portion that is rotatably supported by a shaft hole formed through the bottom of the case, and a bearing portion.
A deformed shaft portion facing the brake element constituting the brake portion and having a width across flats set to be smaller than the outer diameter of the bearing portion.
Is formed continuously in the axial direction,
In the deformed shaft portion, a pair of two-sided width connecting portions connecting the two-sided width portions project outward in the radial direction of the pinion shaft and abut on the bottom of the case in the axial direction of the pinion shaft. It has a pair of regulation parts that regulate movement,
In the process of forming the deformed shaft portion by implanting the rod-shaped material in the axial direction from one end side to form the deformed shaft portion,
A gear forming step of implanting the material from the other end side in the axial direction to form the pinion gear,
The pair of two surfaces is formed in a direction orthogonal to the axial direction of the pinion axis by pressing a part of the pair of two-sided width connecting portions in the thickness direction of the two-sided width portion to plastically deform the pair. A regulation portion forming step of forming the pair of flat regulation portions extending along the radial direction in the circumferential intermediate portion of the width connection portion, and a regulation portion forming step.
A method of manufacturing a brake device for an automobile seat, which is characterized by being equipped with. In the method for manufacturing a brake device for an automobile seat according to claim 5.
A method for manufacturing a brake device for an automobile seat, further comprising a bearing portion cutting step of cutting the outer peripheral portion of the bearing portion to finish it to a required dimension after the regulation portion forming step.

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