JP4923322B2 - Deceleration mechanism - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a gear member support structure, and more particularly to a gear member support structure used for a drive mechanism such as a power seat device for a vehicle.
[0002]
[Prior art]
Conventionally, as this type of support structure, one shown in Japanese Patent Laid-Open No. 8-318767 has been known. This is a reduction in which a worm gear and a wheel gear rotating in mesh with each other are housed in a housing, the worm gear is driven to rotate by a motor mounted outside the housing, and the rotation is reduced and transmitted to a screw shaft connected to the wheel gear. In the device, the worm gear is supported by the shaft portions on both sides of the gear portion, and the bearing away from the motor side uses a bearing member separate from the housing to move the worm gear in the radial direction and the axial direction. The worm gear is supported so as to block, and the bearing closer to the motor side is directly supported by a part of the housing.
[0003]
[Problems to be solved by the invention]
However, with the above-described conventional structure, it is difficult to secure a sufficient inner diameter accuracy as a bearing in the portion directly bearing in the housing depending on the molding of the housing made of a resin material. Since it is close to the part, the load causing the shaft to swing in the radial direction is also large, causing vibration during operation.
[0004]
[Means for Solving the Problems]
The technical means taken in the present invention in order to solve the above technical problem includes a worm gear and a wheel gear which are housed in a housing and rotate in mesh with each other, and shaft portions on both sides of the gear portion of the worm gear. In a reduction mechanism configured to rotatably support the worm gear in the housing and to drive one side of the shaft of the worm gear connected to an electric motor, the worm gear on the side connected to the motor. to fix the inner ring of the bearing member on the shaft, the outer ring of the bearing member constructed by fixing sandwiched between members of the motor side to the housing, the housing and the abutting end member of the electric motor, the shaft together but with the screw holes in the four places constituting the corners of the rectangle to be the center, to contact with the electric motor of the housing The site, two of the screw holes located at one of the diagonal lines of the screw holes in the four places, and the other two located on a diagonal line of the screw hole and selectively two mounting holes that match a, it is to have a connector for power supply to the electric motor at a position corresponding to one side of the screw holes in the side surface of the electric motor.
[0005]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the accompanying drawings. First, a seat slide mechanism 5 using a drive mechanism 2 to which the present invention is applied will be described with reference to FIGS. The seat slide device 5 moves the upper rail 58 fixed to the seat cushion 11 and slidably supported by the lower rail 56 in the front-rear direction of the seat 10 with respect to the lower rail 56 fixed to the vehicle floor 1. A screw shaft 51 that is supported by the upper rail 58 so as to be rotatable and immovable in the axial direction; a nut member 52 that is fixed to the lower rail 56 and screwed to the screw shaft 51; It consists of the drive mechanism 2 connected with the screw shaft 51 which can be read.
[0006]
Next, the drive mechanism 2 will be described. As shown in FIGS. 3 and 4, the drive mechanism 2 includes a housing 30, a worm gear 22 disposed in the housing 30, a housing 30, a mesh with the worm gear 22, and a screw shaft 51. A wheel gear 23 and a motor 24 disposed in the housing 30 and linked to the worm gear 22 are configured. The housing 30 includes a main body 31 and a cover 38, and the main body 31 is formed with two holes 32 and 33 that are orthogonal to each other and connected to each other in the vicinity of the intersection. And the hole 32 penetrates the main body 31, and the hole 33 is a hole having a bottom. A wheel gear 23 is disposed in the through hole 32, and a worm gear 22 is disposed in the other hole 33.
[0007]
As shown in FIG. 4, the worm gear 22 disposed in the hole 33 includes shaft portions 22b and 22c formed coaxially on both sides of the gear portion 22a. A small-diameter shaft portion 221 having a slightly small diameter is formed at the end of the shaft portion 22c on the side connected to the motor 24. On the small-diameter shaft portion 221, a bearing member 41 having an inner ring 41b and an outer ring 41a is provided as an inner ring 41b. And the end portion 222 of the small-diameter shaft portion 221 is crushed and crimped so as to be prevented from coming off. Furthermore, a hole 223 having a rectangular cross section extending along the shaft center is formed in the shaft center portion of the shaft portion 22c, and a connecting cord 61 for transmitting a driving force from the motor 24 described in detail later is inserted. .
[0008]
Furthermore, as detailed in FIG. 4, the main body 31 of the housing 30 is assembled to the end member 244 of the motor 24 with screws 71. The hole 33 of the main body 31 opens to the end member 244 side, the bottom portion is the smallest diameter portion 33a having the smallest inner diameter, the middle portion is the middle diameter portion 33b, and the portion near the opening is the large diameter portion 33c. The outer ring 41a of the bearing member 41 is inserted into the large-diameter portion 33c, contacts the stepped portion 33d between the intermediate-diameter portion 33b and the large-diameter portion 33c on the side surface, and further the end member 244 of the motor 24 The protruding portion 244a is inserted into the large-diameter portion 33c and holds the outer ring 41a so as to be sandwiched between the distal end portions of the protruding portions 244a. The worm gear 22 assembled in this manner is rotatably fixed to the housing 30 and firmly fixed in the axial direction. The outer diameter portion of the protrusion 244a and the inner diameter portion of the large diameter portion 33c are set in a highly accurate fitting relationship, and are configured to minimize the deviation of the rotational axis between the motor 24 and the worm gear 22.
[0009]
The motor 24 has an output shaft 241, and the output shaft 241 has a hole 242 having a rectangular cross section extending along the axis. A hole 242 having a rectangular cross-section opens to the housing 30 side, and one end of a connecting line 61 as shown in detail in FIG. The other end of the connecting cord 61 is inserted into the hole 223 of the worm gear 22 as described above. The connecting rope 61 is made by twisting together a plurality of steel wires having a spring action, and its end 61a has a rectangular cross section by a bushing process, and is an end formed so as to gradually change and become smaller toward the end. It has the parts 61a and 61b. Therefore, even if the dimensional variation of the rectangular hole 242 of the output shaft 241 and the rectangular hole 223 of the worm gear 22 is large, the end portions of the connecting rope 61 are strongly inserted so that they are connected so that there is no play. Is possible. FIG. 6 shows an embodiment of a connecting rope 611 having an end shape different from that of the connecting rope 61. In other words, it has end portions 611a and 611b formed so that the rectangular shape of the cross section in the axial direction is slightly twisted. In this case, when fitted into the hole 242 and the hole 223, the end portion 611a of the connecting cord 611 , 611b torsion spring effect can be fitted without play even if the dimensional variation on the holes 242 and 223 side is large.
[0010]
As shown in FIGS. 1 to 4, the end member 244 of the motor 24 has a rectangular flange portion 244 b at a portion that contacts the main body 31 of the housing 30, and screw holes are provided at four corners of the rectangular flange portion 244 b, respectively. 244c is provided. A power supply connector 245 is attached to the side surface of the motor 24 so as to protrude. On the other hand, the housing 30 attached to the upper rail 58 via a bracket 59 (FIG. 2) is provided with a flange portion 31a. The flange portion 31a has two mounting holes 31b arranged horizontally. For example, even when the installation is set so that the seat slides driven by the motor are symmetrical on the driver seat side and the passenger seat side, the power supply line 8 of the motor 24 can be attached from a certain direction of the seat 10. In addition, the connector 245 is preferably set so as to face a certain direction with respect to the sheet 10. In the motor 24 configured to have the flange portion 244b having the shape as described above, one seat slide 5 is provided on the housing 30 side using a pair of diagonal screw holes 244c on the flange portion 244b. Ritsuke and the mounting hole 31b which is disposed horizontally, on the other seat slide 5, by attaching the mounting holes 244c on another diagonal line on the flange portion 244b, with respect to the seat sliding 5 both the left and right, in the motor 24 of the same shape, it is possible to unify the direction of the connector 245 in a certain direction. As a result, only one type of motor 24 can be used, the number of types of components can be reduced, and the workability of assembly can be improved.
[0011]
The seat slide device 5 configured as described above moves in the front-rear direction by driving the motor 24 when the occupant operates a switch (not shown) for seat front-rear position adjustment. The drive device 2 attached to the seat slide device 5 has the bearing member 41 caulked and fixed on the shaft portion 22c on the side close to the connecting portion with the motor 24, and the housing 30 with high accuracy and the minimum number of parts. The structure in which the shaft is rotationally supported to the side suppresses the vibration of the shaft portion of the worm gear 22, greatly reduces vibration during operation, and the bearing member 41 firmly holds the movement of the worm gear 22 in the axial direction. The shaft of the worm gear 22 generated by the reaction force at the time of stop when the stopper (not shown) of the seat slide device 5 comes into contact with and stops at the rearmost or frontmost adjustment position. Since it can cope with the load in the direction with sufficient strength, quiet operation and durability can be obtained. Further, when the bearing member 41 is caulked and fixed on the shaft portion 22c of the worm gear 22, even if a slight distortion occurs in the rectangular hole 223 formed in the shaft center portion of the shaft portion 22c, there is play at the connecting portion. has a rectangular or connecting cord 61 having an end portion 61a, or twist can ensure quiet operation by using a connecting cord 611 having a rectangular end portion 611a is configured to gradual change so as not to cause .
[Brief description of the drawings]
FIG. 1 is a side view of a seat slide device according to the present invention.
FIG. 2 is a plan view of a lock mechanism portion of the seat slide device according to the present invention.
FIG. 3 is an exploded perspective view of a driving apparatus according to the present invention.
FIG. 4 is a cross-sectional view of a drive device according to the present invention.
FIG. 5 is a plan view of a first embodiment of a connecting line of a driving device according to the present invention.
FIG. 6 is a plan view of a second embodiment of the connecting cable of the driving device according to the present invention.
[Explanation of symbols]
2 Deceleration mechanism 22 Worm gear 22a Gear part 22b Shaft part 22c Shaft part 23 Wheel gear 24 Motor 30 Housing 41 Bearing member 41a Outer ring 41b Inner ring 61 Connecting line 61a End part 611 Connecting line 611a End part

Claims (3)

A worm gear and a wheel gear which are housed in a housing and rotate in mesh with each other, the worm gear is rotatably supported in the housing by shafts on both sides of the gear portion of the worm gear, and the shaft of the worm gear In a speed reduction mechanism configured to drive one side of the motor connected to an electric motor,
To fix the inner ring of the bearing member on the shaft side is connected to the motor of the worm gear, it constitutes the outer race of the bearing member fixed sandwiched between members of the motor side to the housing,
Said housing abutting end member of the electric motor, which has a threaded four holes constituting the shaft corner portions of the rectangle to be the center, the electric motor and the site in contact with the housing, the four points has on one two of the screw holes and selectively two mounting holes that match the diagonally positioned two of the screw holes located on a line, and the other on a diagonal line of one of the threaded holes,
Reduction mechanism, characterized in that it comprises a connector for power supply to the electric motor at a position corresponding to one side of the screw holes in the side surface of the electric motor. The reduction gear according to claim 1, wherein the worm gear and the electric motor are coupled by connecting each end portion of a connecting rope that gradually changes to a rectangular cross section that becomes smaller toward at least one end portion. mechanism. The worm gear and the electric motor are coupled to each other by connecting each end of a connecting rope having a rectangular cross section extending to be twisted along an axial direction to at least one end. The reduction mechanism described.

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