JPH04122279U - electric steering device - Google Patents

Abstract

(57) [Summary] [Purpose] To reduce the weight of the pulley. Reduce costs. [Structure] Equipped with a winding transmission means for transmitting the rotation of the electric motor (16) to the tilt operation screw shaft (13). The pulleys (20) (32) of the wrapping transmission means are integrally formed around the core metal parts (26) (33) and the core metal parts (26) (33) having boss parts (26a) (33a). The synthetic resin part (27) (34) has a rim part (27a) (27b) (34a) with flanges (27c), (27d), and (34b). Anti-rotation protrusions and recesses that fit into each other are formed between the outer peripheral surfaces of the core metal parts (26) and (33) and the inner peripheral surfaces of the resin parts (27 and 34).

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This invention relates to electric steering devices for automobiles, etc. For more details, see At least one of tilt operation and telescopic operation is performed by rotating the electric motor. The present invention relates to an electric steering device in which one or the other is performed.

0002

[Conventional technology]

For example, an electric tilt steering device uses a fixed bracket fixed to the vehicle body. The tilt bracket is attached to the side so that it can swing freely, and the tilt bracket is attached to the fixed bracket side. The tilt bracket is swung by the rotation of the tilt electric motor. solid The fixed bracket supports the lower steering shaft via the lower column. The upper steering shaft is supported by the tilt bracket via the upper column. held. Lower steering shaft and upper steering shaft are freely adjustable They are connected by a joint, and the center of this universal joint is located when the tilt bracket is swinging. It is on the heart line. In addition, a steering wheel is attached to the upper end of the upper steering shaft. is installed. Then, drive the electric motor to swing the tilt bracket. The position of the steering wheel can be changed by changing the position of the steering wheel.

0003 As such an electric tilt steering device, the applicant has proposed a fixed bracket. The screw shaft attached to the front side and the screw that meshes with the screw shaft. Screw nut and winding transmission means that transmits the rotation of the motor shaft to the screw shaft and an eccentric member that connects the screw nut and tilt bracket. proposed (see Utility Model Application Publication No. 2-68265).

0004

[Problem that the idea aims to solve]

However, this tilt steering device has the following problems.

[0005] In other words, the pulley of the above-mentioned winding transmission means is formed entirely of metal. However, the problem was that the weight was large. Moreover, , prepare a separate flange to prevent the belt from coming off, and attach it to the rim of the pulley. As a result, the number of parts increases and the assembly process becomes troublesome. , there is a problem of high cost. Furthermore, the belt may deteriorate due to long-term use. The problem is that the sound level generated between the pulley and belt increases. be.

[0006] The purpose of this invention is to provide an electric steering device that solves the above problems. There is a particular thing.

[0007]

[Means to solve the problem]

The electric steering device based on this idea is At least one of tilt operation and telescopic operation is performed by rotating the electric motor. It is equipped with a motion transmission means for performing either one of the displacements, and the motion transmission means is a screw. - nut, the screw shaft that engages with the screw nut, and the rotation of the motor shaft. A winding transmission means for transmitting rotation to a screw nut or screw shaft. An electric steering device comprising: The pulley of the winding transmission means includes a core metal portion having a boss portion and a core metal portion around the core metal portion. It consists of a synthetic resin part that is formed on the body and has a rim part with a flange, and a core metal part. Anti-rotation unevenness that fits into each other is formed between the outer circumferential surface of the part and the inner circumferential surface of the resin part. This is what is being done.

[0008]

[Effect]

The pulley of the winding transmission means is integrated with a core metal part having a boss part and around the core metal part. It consists of a synthetic resin part with a rim part formed and provided with a flange, so the overall is lighter in weight than those made of metal. In addition, a link with a flange is also available. A synthetic resin part with a hollow part is integrally formed around the core metal part by, for example, injection molding. can do. Furthermore, there is a mutual gap between the outer circumferential surface of the core metal part and the inner circumferential surface of the resin part. The rotation of the motor shaft is prevented by the rotation of the screw because it has projections and depressions that fit together to prevent rotation. When being transmitted to the shaft or screw nut, the resin part wraps around the core metal part. Rotation is prevented.

[0009]

【Example】

Examples of this invention will be described below with reference to the drawings. Please note that the following explanation The left side of Figures 1 and 2 is the front, the right side is the rear, and the top and bottom of Figures 1 and 2 are the top and bottom. shall be.

0010 Figure 1 shows the overall configuration of an automobile electric steering device with a tilt operation function. 2 shows its tilt operation section, and FIG. 3 shows a part of FIG. 2 on an enlarged scale.

[0011] In Figure 1, the fixing bracket (1) fixed to the car body (not shown) is When viewed from above, it has a roughly U-shape with an open rear end, and the lower column (2) is fixed to the front end of the U-shape. ing. The front end of the lower column (2) is also fixed to an appropriate location on the vehicle body using the fixing member (3). has been established. The lower steering shaft (4) is rotatable inside the lower column (2). is supported by Although not shown, the front end of the lower steering shaft (4) is connected to the steering gear.

0012 The tilt bracket (5) extends vertically from the rear of the fixed bracket (1). It is swingably attached by two connecting pins (6). Tilt bracket (5 ) is fixed to the rear end of the outer column tube (8) that constitutes the upper column (7). Although not shown, it is inside the outer column tube (8). Same as Appakola An inner column tube constituting the column (7) is rotatably fitted. in The upper steering shaft (9) is fitted into the Nacolumn tube. The upper steering shaft (9) slides against the inner column tube. However, it is designed not to rotate. Rear end of upper steering shaft (9) A steering wheel (10) is attached to the. Upper steering wheel The front end of the foot (9) is attached to the rear end of the lower steering shaft (4) in a free position (not shown). They are connected via a joint. The center of this universal joint is the pivot of the tilt bracket (5). It is located on the center of motion, that is, on the center line of the connecting pin (6). Also, on the fixing bracket (1) Place the tilt bracket (5) between the front part and the rear part of the top part of the tilt bracket (5). A tension coil spring (11) is attached that biases in the direction of swinging. Illustration omitted However, if necessary, attach the upper steering shaft (9) to the upper column (7). A telescope drive unit is provided to extend and retract the telescope.

[0013] Outside the left part (1a) of the fixing bracket (1) when viewed from the steering wheel (10) side A housing (12) of a movement transmission means for tilt operation is fixedly provided on the surface. As shown in Figure 2, there is a screw that extends approximately vertically at the rear of the housing (12). Both ends of the shaft (13) are rotatably supported via ball bearings (14) and (15). Howe The tilt motor (16) is attached to the screw shaft (13) on the top of the front wall of the housing (12). It is fixed roughly downward so that it is parallel to the The motor shaft (17) is connected to the housing (1 2) It penetrates the wall and protrudes downward, and a small pulley (18) is fixed to this part. . The small pulley (18) has a boss part (18a) and a rim part (18b) integrally formed of metal. , a separately prepared flange (19) is attached to the rim part (18b). .

[0014] A large plate is installed between the screw shaft (13) and the electric motor (16) inside the housing (12). The intermediate pulley (20), in which the pulley part (21) and the small pulley part (22) are integrally formed, is connected to the bolt (23). It is rotatably attached to the base plate (25) with a nut (24), and this base A plate (25) is fixed to the housing (12) so that its position can be adjusted. The intermediate pulley (20) is A core metal part (26) having a boss part (26a) common to both pulley parts (21) and (22), and a core metal part (26). is integrally formed around the pulley parts (21) and (22), for example by injection molding. It consists of a synthetic resin part (27) having rubber parts (27a) and (27b). Rims of both pulleys (21) (22) Flanges (27c) (27d) are integrally formed in the portions (27a) and (27b). As shown in Figure 3 By applying knurling in advance to appropriate locations on the outer circumferential surface of the core metal part (26), A large number of convex portions (28) and concave portions (29) are formed, so injection molding is performed around them. The inner circumferential surface of the resin portion (27) that has been removed has a recess (30) and a recess (30) that fit into the projection (28) and recess (29). A convex portion (31) is formed, and the fitting between the metal core portion (26) and the resin portion (27) Relative rotation is prevented.

[0015] A large pulley (32) is fixed to the bottom of the screw shaft (13). This big pool The core metal part (33) having the boss part (33a) and the periphery of the core metal part (33), for example, are The synthetic resin part (34) is integrally formed by extrusion molding and has a rim part (34a). Ru. A flange (34b) is integrally formed on the rim portion (34a). In addition, the core metal part (3 3) Knurl in advance at appropriate locations on the outer circumferential surface in the same way as the intermediate pulley (20). As a result, many convex portions and concave portions are formed, which causes injection molding to occur around them. The inner peripheral surface of the molded resin part (34) has a concave part and a convex part that fit into the convex part and the concave part. The relative rotation between the core metal part (33) and the resin part (34) is is prevented.

[0016] Then, the small pulley (18) and the large pulley of the intermediate pulley (20) are fixed to the motor shaft (17). The timing belt (35) is attached to the part (21), and the small pulley part (22) of the intermediate pulley (20) The timing belt (36) is hooked onto the large pulley (32) fixed to the screw shaft (13). I'm being kicked.

[0017] A screw nut (37) is engaged with the screw shaft (13). blood The front end of the left part (5a) of the bolt bracket (5) is located just to the right of the screw nut (37). Located on the side. Outside the front end of the left side part (5a) of the tilt bracket (5) The arms (39) are spaced apart from each other by a cylindrical spacer (not shown) and bolts (38). This arm (39) is located immediately to the left of the screw nut (37). are doing. Pins (40) are integrally formed on both the left and right sides of the screw nut (37). An eccentric disk (42) is rotatably attached to these pins (40) via a spherical bushing (41). There is. The eccentric disk (42) is attached to the left side of the tilt bracket (5) via a ball bearing (not shown). It is fitted inside the hole formed in the portion (5a) and the arm (39). This eccentric circle As described later, the plate (42) supports the linear movement of the screw nut (37) and the tilt bracket. In order to absorb the difference in trajectory between the left part (5a) of the arm (5) and the circular arc motion of the arm (39), belongs to.

[0018] In the above tilt steering device, the rotation of the electric motor (16) is controlled by the timing The screw shaft (13) is decelerated by belts (35) (36) and pulleys (18) (20) (32). This causes the screw nut (37) to move along the screw shaft (13). to move up and down. The vertical movement of this screw nut (37) causes an eccentric disc. (42) to convert the tilt bracket (5) into rocking motion, and the steering wheel (1 0) tilts up and down. The vertical movement of the screw nut (37) is a linear motion, and the chi The swing of the root bracket (5) is a circular motion centered on the connecting pin (6), but the As the screw nut (37) moves, the center line of the eccentric disc (42) moves through the connecting pin (6). The eccentric disk (42) rotates around the center line of the pin (40) so that it forms an arc with the center. As a result, the difference in these trajectories is absorbed, and the linear movement of the screw nut (37) is This is converted into the swinging motion of the tilt bracket (5).

[0019] In the above, the small pulley (18) attached to the motor shaft (17) is small and therefore heavy. The amount is not very large, so the boss part (18a) and rim part (18b) are made of metal. It is formed integrally and a separately prepared flange (19) is attached to the rim part (18b). However, instead of this, a core metal part having a boss part and a core metal part formed integrally around the core metal part are used. The synthetic resin part has a rim part with a flange. Anti-rotation unevenness that fits into each other is formed between the peripheral surface and the inner peripheral surface of the resin part. You can use whatever you have.

[0020]

[Effect of the idea]

According to the electric steering device of this invention, as described above, the wrap-around transmission means The pulley consists of a core metal part and a synthetic resin part integrally formed around the core metal part. Therefore, the overall weight is lighter than the conventional one. In addition, a link with a flange is also available. A synthetic resin part with a hollow part is integrally formed around the core metal part by, for example, injection molding. This simplifies manufacturing. Moreover, the number of parts and assembly time are Fewer in number, lower costs. In addition, the rotation of the motor shaft is caused by a screw shaft. The resin part rotates around the core metal part when it is transmitted to the bolt or screw nut. Since the rotation of the motor is accurately transmitted to the screw nut and the Ability to perform accurate rotation and/or telescopic operations. In addition, the belt is a pulley Since power is transmitted by contacting the resin part of the belt, the belt will not deteriorate even after long-term use. Therefore, the level of sound generated between the pulley and belt increases. It can be prevented.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway side view of a main part of an electric tilt steering device showing an embodiment of the invention.

FIG. 2 is an enlarged partial cutaway view of FIG. 1;

FIG. 3 is a partially enlarged view of FIG. 2;

[Explanation of symbols]

13 Screw shaft 16 Electric motor 20 Intermediate pulley 26 Core metal part 26a Boss part 27 Synthetic resin section 27a Rim part 27b Rim part 27c flange 27d flange 32 Large pulley 33 Core metal part 33a Boss part 34 Synthetic resin section 34a Rim part 34b flange 37 Screw nut

Claims (1)

[Scope of utility model registration request] 1. A motion transmitting means for performing at least one of a tilt operation and a telescopic operation by rotation of an electric motor, the motion transmitting means comprising: a screw nut; a screw shaft meshing with the screw nut; An electric steering device comprising a winding transmission means for transmitting rotation of an electric motor shaft to a screw nut or a screw shaft, wherein a pulley of the winding transmission means has a core part having a boss part and a periphery of the core metal part. A synthetic resin part is integrally formed with a rim part having a flange, and anti-rotation unevenness that fits into each other is formed between the outer peripheral surface of the core metal part and the inner peripheral surface of the resin part. Electric steering device.