JP2006001424A - Electric power steering device and its assembling method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To assemble a key lock collar having the diameter larger than the inside diameter of a sensor coil, and to easily assemble a worm wheel without increasing the number of components. <P>SOLUTION: A small diameter sensor coil 13 is passed between steering shafts (an input shaft 3 and an output shaft 6), and a worm wheel 15 having the diameter larger than that of the coil 13 and a key lock collar 4 having the diameter larger than that of the coil 13 are mounted on both end sides. In this situation, the worm wheel 15 is assembled later to the steering shafts (the input shaft 3 and the output shaft 6) passing through the sensor coil 13 with the key lock collar 4 fixed thereto. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an electric power steering device including an antitheft device and an assembling method thereof.

  As an electric power steering device for a vehicle, the rotation output of an electric motor serving as an auxiliary steering torque is decelerated by a gear device and transmitted to the output shaft of the steering mechanism, and the steering force applied to the steering wheel is assisted to steer the wheel. What is comprised so that it may perform is known. In such an electric power steering apparatus, power is transmitted to the output shaft while reducing the rotation of the electric motor by using a reduction mechanism provided in the housing.

  In such an electric power steering apparatus, the input shaft that receives the steering force from the steering wheel and the output shaft that transmits the steering force to the wheels are connected by a torsion bar. The torsion torque relating to the torsion bar is detected, and the steering torque necessary for the output control of the auxiliary steering force is adjusted.

  The input shaft is normally assembled by inserting the column member from the sensor housing side into the column member after the column member is fixed to the sensor housing and the sensor coil of the sensor mechanism is assembled.

  On the other hand, in order to prevent theft of the vehicle, the vehicle is provided with an anti-theft device, and when the driver removes the key, the input shaft is fixed to the column member and the steering wheel is maintained in a non-rotating state. It has come to be.

  In such an anti-theft device, a key lock collar having a plurality of holes is fixed to the outer peripheral surface of the input shaft by press-fitting or the like, and when the driver removes the key, it moves out and retracts in the radial direction from the column member side The shaft to be engaged enters and engages with the hole of the key lock collar, so that the input shaft and the steering wheel can be kept non-rotating.

  By the way, it is obvious that even if the same torque is supported, it is obvious that the large diameter part can be suppressed with a weaker force than the small diameter part. The strength is weak and good. Since the force related to the key bolt that moves in and out becomes weak, the key bolt that engages the hole of the key lock collar may be weak. The part that receives the force (the housing that holds the key bolt, the column part that receives the force from the housing) Can also reduce the strength.

  Also, when using a slip ring, the slip torque is determined by the shaft diameter and key lock collar inner diameter, but if the diameter is increased, the slip torque will become dull and the product will fall within a certain slip torque range. This eliminates the need for processing accuracy and can reduce manufacturing costs.

  However, when there is a sensor portion, the key lock collar has not been able to have a large diameter until now, limited to the inner diameter of the sensor coil.

  As a method for making the key lock collar larger than the inner diameter of the sensor coil, there are Patent Documents 1 to 3 described later.

  Thus, when trying to increase the diameter of the key lock collar, the outer diameter of the key lock collar is larger than the inner diameter of the sensor coil attached to the sensor housing, and the output shaft is larger than the inner diameter of the sensor coil. The worm wheel of the larger reduction mechanism is fitted.

  That is, the input shaft and the output shaft are provided with a worm wheel on the vehicle front side and a key lock collar on the vehicle rear side, which are larger than the inner diameter of the sensor coil, on both ends.

  For this reason, in Patent Documents 1 to 3, when the electric power steering apparatus is assembled, the input shaft is divided into two parts, the front side and the rear side of the vehicle. While fixing the key lock collar to the rear input shaft, the output shaft with the worm wheel attached (fitted) and the front input shaft are combined and inserted into the sensor housing, and the sub-assembly body Is assembled.

After that, the input shaft on the rear side to which the key lock collar is fixed is combined with the input shaft on the front side of the subassembly body, thereby completing the assembly.
JP 2000-85596 A JP 2000-318626 A JP 2003-72566 A

  However, as in Patent Documents 1 to 3, dividing the input shaft of the electric power steering device in order to mount the key lock collar of the anti-theft device leads to an increase in the number of parts and the division. The product union operation is complicated, and as a result, the manufacturing cost increases.

  Although it may be necessary to simply increase the inner diameter of the sensor coil for such a problem, a new design of the coil may require considerable effort and increase the manufacturing cost. The inner diameter of the sensor coil is being standardized, and the diameter of the steering shaft is limited accordingly.

  The present invention has been made in view of the above-described circumstances, and it is possible to assemble a key lock collar larger than the inner diameter of the sensor coil without incurring an increase in the number of parts. It is an object of the present invention to provide an electric power steering apparatus and an assembling method thereof that can facilitate attachment and can freely set the diameter of a key lock collar.

In order to achieve the above object, an electric power steering apparatus according to claim 1 of the present invention generates an auxiliary steering torque from an electric motor in response to a steering torque applied to a steering wheel, and decelerates by a reduction gear. Is transmitted to the output shaft of the steering mechanism,
Provided with a driven gear of the speed reducer on the vehicle front side of the sensor mechanism, and provided with a key lock collar of the anti-theft device on the vehicle rear side of the sensor mechanism,
In the electric power steering apparatus in which the outer diameter of the driven gear and the key lock collar is larger than the inner diameter of the sensor coil of the sensor mechanism,
The driven gear is assembled later on a steering shaft having the key lock collar fixed and the sensor coil inserted therethrough.

In the electric power steering apparatus according to claim 2, “α” is a distance between the vehicle rear end of the housing and the vehicle front end of the key lock collar, and “β” is a vehicle front end of the housing, The distance between the vehicle front side surface of the concave groove for the jig of the output shaft
“Α> β” is set.

  The electric power steering apparatus according to a third aspect is characterized in that the steering shaft has a jig mounting portion for mounting a jig used when the driven gear is mounted.

  The electric power steering apparatus according to a fourth aspect is characterized in that the jig mounting portion is an output shaft fixing screw formed on the steering shaft.

  The electric power steering apparatus according to a fifth aspect is characterized in that the jig mounting portion is formed on the steering shaft and is a diameter / change portion in which a diameter is changed.

  The electric power steering apparatus according to a sixth aspect is characterized in that the jig mounting portion is a partial flat portion formed on the steering shaft.

According to a seventh aspect of the present invention, there is provided a method for assembling an electric power steering apparatus, wherein an auxiliary steering torque is generated from an electric motor in response to a steering torque applied to a steering wheel, and is decelerated by a reduction gear to be output to a steering mechanism. Communicate
Provided with a driven gear of the speed reducer on the vehicle front side of the sensor mechanism, and provided with a key lock collar of the anti-theft device on the vehicle rear side of the sensor mechanism,
In an assembly method for assembling an electric power steering device in which the outer diameter of the driven gear and the key lock collar is larger than the inner diameter of the sensor coil of the sensor mechanism,
The driven gear is assembled later on a steering shaft having the key lock collar fixed and the sensor coil inserted therethrough.

In the method for assembling the electric power steering apparatus according to the eighth aspect, “α” is a distance between the rear end of the housing of the housing and the front end of the key lock collar, and “β” is the front of the housing of the housing. A distance between the end and the vehicle front side surface of the concave groove for the output shaft
“Α> β” is set.

  According to a ninth aspect of the present invention, there is provided a method for assembling an electric power steering apparatus, wherein the steering shaft has a jig mounting portion for mounting a jig used when the driven gear is mounted.

  The assembly method of the electric power steering apparatus according to claim 10 is characterized in that the jig mounting portion is an output shaft fixing screw formed on the steering shaft.

  According to an eleventh aspect of the method for assembling an electric power steering apparatus, the jig mounting portion is formed on the steering shaft, and is a diameter / change portion having a changed diameter.

  The electric power steering apparatus assembling method according to a twelfth aspect is characterized in that the jig mounting portion is a partial flat portion formed on the steering shaft.

  As described above, according to the present invention, since the driven gear is assembled later on the steering shaft with the key lock collar fixed and the sensor coil inserted, the number of parts is increased. Therefore, a key lock collar larger than the inner diameter of the sensor coil can be assembled, and as a result, the assembly of the worm wheel can be facilitated, and the diameter of the key lock collar can be set freely.

  Since the driven gear is retrofitted as described above, the assembly method of the present invention can be applied to a steering shaft (input shaft) having a collapsed structure.

  Furthermore, since there are almost no restrictions on the fitting part between the driven gear and the steering shaft, it is a part that can be freely designed by the manufacturer of the electric power steering device, and it is possible to standardize the design. The effect can also be expected.

  Hereinafter, an electric power steering device and an assembling method thereof according to an embodiment of the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1A is a longitudinal sectional view of the electric power steering apparatus according to the first embodiment of the present invention, and FIG. 1B is a partial view of the electric power steering apparatus according to the reference example of the first embodiment. FIG.

  First, an electric power steering apparatus that has been assembled according to the present embodiment will be described, and then an assembly method for the electric power steering apparatus will be described.

  In the column assist type electric power steering device shown in FIG. 1A, a steering column input shaft 3 is rotatably supported via a bearing 2 on a steering column 1 having a non-collapse structure.

  A key lock collar 4 of the anti-theft device is press-fitted into the intermediate portion of the input shaft 3 via a slip ring 5. When the driver pulls out the key, a shaft (not shown) that protrudes and retreats in the radial direction from the hole 1a of the steering column 1 enters and engages with the hole 4a of the key lock collar 4, whereby the input shaft 3 and A steering wheel (not shown) can be kept non-rotating.

  Further, the slip ring 5 allows relative rotation with respect to the input shaft 3 when a certain torque or more is applied to the key lock collar 4.

  An output shaft 6 is connected to the vehicle front side of the input shaft 3 via a torsion bar 7 described later. The output shaft 6 is inserted through a housing 8 and a cover 9, and a steering gear (not shown) is connected to the front side of the vehicle via a universal joint (not shown). The output shaft 6 is rotatably supported by bearings 9a and 9b of the cover 9.

  The base end of the torsion bar 7 is press-fitted and fixed to the vehicle front side of the input shaft 3, and the torsion bar 7 extends inside the hollow output shaft 6, and the tip of the torsion bar 7 extends to the output shaft 6. It is fixed to the end of this by a fixing pin 10.

  Detection grooves 11 of the torque sensor mechanism are formed on the vehicle rear side of the output shaft 6, and a sleeve 12 of the torque sensor mechanism is disposed outside the detection grooves 11 in the radial direction. The sleeve 12 has a vehicle rear side end fixed to a vehicle front side end of the input shaft 3 by caulking or the like. A sensor coil 13 and a substrate are provided outside the sleeve 12 in the radial direction.

  A worm wheel 15 meshed with a worm 14 that is a drive shaft of an electric motor (not shown) is fitted and attached to the output shaft 6. As will be described later, the worm wheel 15 is configured to be press-fitted and fitted into the large-diameter portion 6a of the output shaft 6 and fixed so as not to be relatively rotatable.

  As will be described later, a step S (diameter / change portion) is provided on the vehicle rear side of the worm wheel 15 of the output shaft 6 and on the vehicle front side of the sensor coil 13 by forming the sensor coil 13 with a large diameter. It is.

  Therefore, the steering force generated when the driver steers the steering wheel (not shown) is transmitted to the steered wheels (not shown) via the input shaft 3, the torsion bar 7, the output shaft 6, and the rack and pinion type steering device. Is done. Further, the rotational force of the electric motor is transmitted to the output shaft 6 via the worm 14 and the worm wheel 15, and the output shaft 6 can be controlled by appropriately controlling the rotational force and the rotational direction of the electric motor. An appropriate steering assist torque can be applied.

  Next, when assembling the non-collapsible electric power steering apparatus configured as described above, first, the key lock collar 4 is assembled to the input shaft 3 of the steering shaft via the slip ring 5 by press fitting or the like.

  The steering shaft (input shaft 3 and output shaft 6) with the key lock collar 4 is inserted into the housing 8 in the direction of the arrow shown in the figure, and the inner diameter of the sensor coil 13 of the sensor mechanism integrated with the housing 8 is inserted. The

  Thereafter, the worm wheel 15 is press-fitted into the large-diameter portion 6a of the output shaft 6 of the steering shaft and is fixed so as not to be relatively rotatable.

  Finally, the steering column 1 and the cover 9 are coupled to both sides of the housing 8 to complete the electric power steering apparatus.

  As described above, in the present embodiment, the small-diameter sensor coil 13 is inserted between the steering shaft (the input shaft 3 and the output shaft 6), and the worm wheel 15 having a larger diameter than the coil 13 is disposed at both ends thereof. A key lock collar 4 having a diameter larger than 13 is attached. In such a case, the worm wheel 15 is assembled later on the steering shaft (input shaft 3 and output shaft 6) through which the key lock collar 4 is fixed and the sensor coil 13 is inserted. The key lock collar 4 larger than the inner diameter of the sensor coil 13 can be assembled without incurring an increase in the width of the sensor coil 13, and as a result, the worm wheel 15 can be easily assembled. The dimensions can be set freely.

  Further, in the present embodiment, a step S (diameter / change portion) is formed on the vehicle rear side of the worm wheel 15 of the output shaft 6 and on the vehicle front side of the sensor coil 13 by forming it with a large diameter. It is provided. A jig groove 17 is formed on the rear side of the step S.

  This step S (the groove 17 for jig) is an axial load generated when the worm wheel 15 is assembled to the output shaft 6 (because the worm wheel 15 is assembled to the output shaft 6 because of axial press-fitting). It is possible to prevent the excessive load from being transmitted to the sensor mechanism connected to the output shaft 6. Instead of the step S (the jig concave groove 17), an output shaft fixing screw may be used to receive the axial load at the time of press-fitting, and the sensor coil 13 is partially formed on the front side of the vehicle. You may receive the axial load at the time of press injection by a plane part.

  Next, in the reference example shown in FIG. 1B, since the input shaft 3 of the steering shaft is formed hollow and the worm wheel 15 is retrofitted as described above, the key lock collar 4 is used. Instead, the hollow input shaft 3 may be formed to have a large diameter, and a lock hole 3a may be formed in the large diameter portion, whereby the key lock collar may be configured integrally.

  Next, FIG. 2 is a longitudinal sectional view of the electric power steering apparatus according to the first embodiment of the present invention, showing a step of fixing the worm wheel and a state where a jig is mounted. .

  As shown in FIG. 1, the symbol “α” is the distance between the vehicle rear end of the housing 8 and the vehicle front end of the key lock collar 4, and the symbol “β” is the vehicle front end of the housing 8. The distance between the concave groove 17 for jig of the output shaft 6 and the vehicle front side surface is set to “α> β”.

  As a result, “α−β” is a gap for attaching the jig G that receives the load of the input shaft 3 when the worm wheel 15 is press-fitted.

  That is, as shown in FIG. 2, when the worm wheel 15 is press-fitted, the input shaft 3 and the output shaft 4 move to the front side of the vehicle so that “α” is zero with respect to the housing 8.

  The vehicle front side surface of the jig concave groove 17 of the output shaft 6 is also exposed from the vehicle front end of the housing 8 because it is “α> β” when it moves to the vehicle front side by this movement “α”. Can do.

  Therefore, as shown in FIG. 2, the jig G can be mounted in the gap of “α−β”.

  From the above, when the worm wheel 15 is press-fitted, as shown in FIG. 2, the jig G is mounted in the jig groove 17, and in this state, a load (F ).

  As a result, the worm wheel 15 is press-fitted and fitted into the large-diameter portion 6a of the output shaft 6 and is fixed so as not to be relatively rotatable.

  Next, FIG. 3 is a longitudinal sectional view of an electric power steering apparatus according to a modification of the first embodiment of the present invention.

  In this modification, as shown in FIG. 3, the housing 8 and the cover 9 are configured to be divided on the vehicle rear side with respect to the first embodiment. As a result, the worm gear 14 and the worm wheel 15 are accommodated in the cover 9 on the vehicle front side. Further, the bearing 8 a on the vehicle rear side is interposed between the housing 8 and the output shaft 6. Furthermore, the worm wheel 15 is fitted to the output shaft 6 of the steering shaft, and the nut 16 is tightened via the bearing 9a, so that the relative rotation is not possible.

(Second Embodiment)
FIG. 4 is a longitudinal sectional view of an electric power steering apparatus according to the second embodiment of the present invention.

  In this embodiment, as is apparent from the drawings, the basic structure is the same as that of the first embodiment, and only different points will be described.

  In the present embodiment, the collapsed steering column is composed of an upper column 21 on the rear side of the vehicle and a lower column 22 on the front side of the vehicle that can be collapsible with the upper column 21. The lower column 22 collapses so that it can move forward of the vehicle.

  The input shaft is composed of a hollow upper shaft 31 on the rear side of the vehicle and a solid lower shaft 32 on the front side of the vehicle slidably fitted thereto. At the time of a secondary collision, the upper shaft 31 is a lower shaft. 32 can move forward of the vehicle.

  A key lock collar 4 of an anti-theft device is welded to the middle large diameter portion of the hollow upper shaft 31. When the driver pulls out the key, a shaft (not shown) that protrudes and retracts in the radial direction from the hole 21a of the upper column 21 enters the hole 4a of the key lock collar 4 and engages therewith, whereby the input shaft (31 32) and the steering wheel (not shown) can be kept non-rotating.

  The output shaft 6 is rotatably supported by a bearing 8a on the housing 8 side and a bearing 9a on the cover 9 side.

  In the present embodiment, a serration portion 6b is formed on the output shaft 6 so that the worm wheel 15 is serrated.

  When assembling the electric power steering apparatus, first, the key lock collar 4 is assembled to the upper shaft 31 by welding or the like.

  A steering shaft (input shafts 31, 32 and output shaft 6) with a key lock collar 4 is inserted into the housing 8 in the direction of the arrow shown in the drawing, and the inner diameter of the sensor coil 13 of the sensor mechanism integrated with the housing 8 is reduced. It is inserted.

  Thereafter, the worm wheel 15 is serrated to the serration portion 6b of the output shaft 6 of the steering shaft, and the nut 16 is tightened via the bearing 9a, so that the relative rotation is not possible.

  Finally, the steering columns (21, 22) and the cover 9 are coupled to both sides of the housing 8 to complete the electric power steering apparatus.

  From the above, in the present embodiment, the small-diameter sensor coil 13 is inserted between the steering shafts (the input shafts 31 and 32 and the output shaft 6), and the worm wheel 15 larger in diameter than the coil 13 is inserted at both ends thereof. The key lock collar 4 having a diameter larger than that of the coil 13 is attached. In such a case, since the worm wheel 15 is assembled later on the steering shaft (input shafts 31 and 32 and output shaft 6) through which the key lock collar 4 is fixed and the sensor coil 13 is inserted, The key lock collar 4 larger than the inner diameter of the sensor coil 13 can be assembled without causing an increase in the number of parts, and as a result, the worm wheel 15 can be easily assembled. The diameter dimension of can also be set freely.

  Since the worm wheel 15 is serrated on the output shaft 6 and no axial load is generated when the worm wheel 15 is assembled, a step S (diameter as in the first embodiment) is formed on the output shaft 6.・ There is no need to provide a change part.

  An O-ring 40 is provided on the rear side of the serration portion 6b of the output shaft 6. As a result, the O-ring 40 is sandwiched between the output shaft 6 and the worm wheel 15 to prevent backlash between the output shaft 6 and the worm wheel 15.

(Third embodiment)
FIG. 5 is a longitudinal sectional view of an electric power steering apparatus according to the third embodiment of the present invention.

  In this embodiment, as is apparent from the drawings, the basic structure is the same as that of the first embodiment, and only different points will be described.

  In the present embodiment, the worm wheel 15 is fitted to the large-diameter portion 6a of the output shaft 6 via the slip ring 50 that functions as a torque limiter.

  When the auxiliary steering torque is transmitted from the electric motor (not shown) through the worm wheel 15 by the slip ring 50, the worm wheel 15 and the output shaft 6 do not rotate relatively, but the wheels are curbstones, etc. When the impact load is received from the steering gear side due to collision with the steering wheel, the relative rotation between the worm wheel 15 and the output shaft 6 is allowed, so that the worm wheel 15 can be protected.

  When assembling the electric power steering apparatus, first, the key lock collar 4 is assembled to the input shaft 3 of the steering shaft by welding or the like. The steering shaft (input shaft 3 and output shaft 6) with the key lock collar 4 is inserted into the housing 8, and the housing 8 is inserted through the inner diameter of the sensor coil 13 of an integral sensor mechanism.

  Thereafter, the worm wheel 15 is press-fitted into the large-diameter portion 6a of the output shaft 6 of the steering shaft via the slip ring 50, and is fixed so as not to be relatively rotatable. Finally, the steering column 1 and the cover 9 are coupled to both sides of the housing 8 to complete the electric power steering apparatus.

  As described above, in the present embodiment, the small-diameter sensor coil 13 is inserted between the steering shaft (the input shaft 3 and the output shaft 6), and the worm wheel 15 having a larger diameter than the coil 13 is disposed at both ends thereof. A key lock collar 4 having a diameter larger than 13 is attached. In such a case, the worm wheel 15 is assembled later on the steering shaft (input shaft 3 and output shaft 6) through which the key lock collar 4 is fixed and the sensor coil 13 is inserted. The key lock collar 4 larger than the inner diameter of the sensor coil 13 can be assembled without incurring an increase in the width of the sensor coil 13, and as a result, the worm wheel 15 can be easily assembled. The dimensions can be set freely.

  Further, in the present embodiment, a step S (diameter / change portion) is formed on the vehicle rear side of the worm wheel 15 of the output shaft 6 and on the vehicle front side of the sensor coil 13 by forming it with a large diameter. It is provided. This step S can receive an axial load generated when the worm wheel 15 is assembled to the output shaft 6 (because the worm wheel 15 is assembled to the output shaft 6 because of axial press-fitting), and the output shaft It is possible to prevent an extra load from being transmitted to the sensor mechanism connected to 6. In place of this step S, an output shaft fixing screw may be used to receive the axial load during press fitting, and the shaft during press fitting may be provided by a partial flat portion formed on the vehicle front side of the sensor coil 13. You may receive a directional load.

(Fourth embodiment)
FIG. 6A is a longitudinal sectional view of an electric power steering apparatus according to a fourth embodiment of the present invention, and FIG. 6B is a sectional view taken along line bb in FIG.

  In this embodiment, as is apparent from the drawings, the basic structure is the same as that of the first or second embodiment, and only different points will be described.

  In the present embodiment, the collapsed steering column is composed of an upper column 21 on the rear side of the vehicle and a lower column 22 on the front side of the vehicle that can be collapsible with the upper column 21. The lower column 22 collapses so that it can move forward of the vehicle.

  The input shaft is composed of a hollow upper shaft 31 on the rear side of the vehicle and a solid lower shaft 32 on the front side of the vehicle slidably fitted thereto. At the time of a secondary collision, the upper shaft 31 is a lower shaft. 32 can move forward of the vehicle.

  The key lock collar 4 of the anti-theft device is press-fitted into the large diameter portion in the middle of the hollow upper shaft 31. When the driver pulls out the key, a shaft (not shown) that protrudes and retracts in the radial direction from the hole 21a of the upper column 21 enters the hole 4a of the key lock collar 4 and engages therewith, whereby the input shaft (31 32) and the steering wheel (not shown) can be kept non-rotating.

  The output shaft 6 is rotatably supported by a bearing 8a on the housing 8 side and a bearing 9a on the cover 9 side.

  In the present embodiment, a taper portion 6c is formed on the output shaft 6 so that the worm wheel 15 is taper-fitted. By this taper fitting, the output shaft 6 and the worm wheel 15 are made relatively non-rotatable by the frictional force of both.

  In this case, as shown in FIG. 6B, a pair of partial flat portions 60 and 60 are formed on the vehicle rear side of the tapered portion of the output shaft 6. By holding the pair of partial flat portions 60, 60, the nut 16 can be tightened without applying excessive torsional torque to the sensor mechanism.

  When assembling the electric power steering apparatus, first, the key lock collar 4 is assembled to the upper shaft 31 by welding or the like.

  A steering shaft (input shafts 31, 32 and output shaft 6) with a key lock collar 4 is inserted into the housing 8 in the direction of the arrow shown in the drawing, and the inner diameter of the sensor coil 13 of the sensor mechanism integrated with the housing 8 is reduced. It is inserted.

  After that, the worm wheel 15 is taper-fitted to the taper portion 6c of the output shaft 6 of the steering shaft, and the nut 16 is tightened via the bearing 9a, so that the relative rotation is not possible. At this time, as described above, by holding the pair of partial flat portions 60, 60, the nut 16 can be tightened without applying excessive torsional torque to the sensor mechanism.

  Finally, the steering columns (21, 22) and the cover 9 are coupled to both sides of the housing 8 to complete the electric power steering apparatus.

  From the above, in the present embodiment, the small-diameter sensor coil 13 is inserted between the steering shafts (the input shafts 31 and 32 and the output shaft 6), and the worm wheel 15 larger in diameter than the coil 13 is inserted at both ends thereof. The key lock collar 4 having a diameter larger than that of the coil 13 is attached. In such a case, since the worm wheel 15 is assembled later on the steering shaft (input shafts 31 and 32 and output shaft 6) through which the key lock collar 4 is fixed and the sensor coil 13 is inserted, The key lock collar 4 larger than the inner diameter of the sensor coil 13 can be assembled without causing an increase in the number of parts, and as a result, the worm wheel 15 can be easily assembled. The diameter dimension of can also be set freely.

  In addition, this invention is not limited to embodiment mentioned above, A various deformation | transformation is possible.

(A) is a longitudinal cross-sectional view of the electric power steering apparatus according to the first embodiment of the present invention, and (b) is a partial longitudinal section of the electric power steering apparatus according to the reference example of the first embodiment. FIG. BRIEF DESCRIPTION OF THE DRAWINGS It is a longitudinal cross-sectional view of the electric power steering apparatus which concerns on 1st Embodiment of this invention, Comprising: While showing the process of fixing a worm wheel, it is a figure which shows the state which mounted | wore the jig | tool. It is a longitudinal cross-sectional view of the electric power steering apparatus which concerns on the modification of 1st Embodiment of this invention. It is a longitudinal cross-sectional view of the electric power steering apparatus which concerns on 2nd Embodiment of this invention. It is a longitudinal cross-sectional view of the electric power steering apparatus which concerns on 3rd Embodiment of this invention. (A) is a longitudinal cross-sectional view of the electric power steering apparatus which concerns on 4th Embodiment of this invention, (b) is sectional drawing along the bb line of (a).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Steering column 1a Hole 2 Bearing 3 Input shaft 4 Key lock collar 4a Hole 5 Slip ring 6 Output shaft 6a Large diameter part 6b Serration part 6c Taper part 7 Torsion bar 8 Housing 8a Bearing 9 Cover 9a, 9b Bearing 10 Fixed pin 11 Detection Groove 12 sleeve 13 sensor coil 14 worm 15 worm wheel 16 nut 17 concave groove for jig 21 upper column 21a hole 22 lower column 31 upper shaft 32 lower shaft 40 O-ring 50 slip ring 60 partial flat surface S step (diameter and diameter) Change part)
G Jig

Claims (12)

In response to the steering torque applied to the steering wheel, an auxiliary steering torque is generated from the electric motor, decelerated by the speed reducer, and transmitted to the output shaft of the steering mechanism,
Provided with a driven gear of the speed reducer on the vehicle front side of the sensor mechanism, and provided with a key lock collar of the anti-theft device on the vehicle rear side of the sensor mechanism,
In the electric power steering apparatus in which the outer diameter of the driven gear and the key lock collar is larger than the inner diameter of the sensor coil of the sensor mechanism,
An electric power steering apparatus, wherein the driven gear is assembled later on a steering shaft having the key lock collar fixed and the sensor coil inserted therethrough. “Α” is the distance between the vehicle rear end of the housing and the vehicle front end of the key lock collar, and “β” is the vehicle front end of the housing and the vehicle front of the jig groove in the output shaft. The distance between the sides,
The electric power steering apparatus according to claim 1, wherein “α> β” is set.   The electric power steering apparatus according to claim 1 or 2, wherein the steering shaft has a jig mounting portion for mounting a jig used when the driven gear is attached.   The electric power steering apparatus according to claim 3, wherein the jig mounting portion is an output shaft fixing screw formed on the steering shaft.   The electric power steering apparatus according to claim 3, wherein the jig mounting portion is a diameter / change portion formed on the steering shaft and having a diameter changed.   The electric power steering apparatus according to claim 3, wherein the jig mounting portion is a partial flat portion formed on the steering shaft. In response to the steering torque applied to the steering wheel, an auxiliary steering torque is generated from the electric motor, decelerated by the speed reducer, and transmitted to the output shaft of the steering mechanism,
Provided with a driven gear of the speed reducer on the vehicle front side of the sensor mechanism, and provided with a key lock collar of the anti-theft device on the vehicle rear side of the sensor mechanism,
In an assembly method for assembling an electric power steering device in which the outer diameter of the driven gear and the key lock collar is larger than the inner diameter of the sensor coil of the sensor mechanism,
An assembly method of an electric power steering apparatus, wherein the driven gear is assembled later on a steering shaft having the key lock collar fixed and the sensor coil inserted therethrough. “Α” is the distance between the vehicle rear end of the housing and the vehicle front end of the key lock collar, and “β” is the vehicle front end of the housing and the vehicle front of the jig groove in the output shaft. The distance between the sides,
8. The method of assembling the electric power steering apparatus according to claim 7, wherein “α> β” is set.   9. The assembly method for an electric power steering apparatus according to claim 7, wherein the steering shaft has a jig mounting portion for mounting a jig used when the driven gear is attached.   The method of assembling an electric power steering apparatus according to claim 9, wherein the jig mounting portion is an output shaft fixing screw formed on the steering shaft.   10. The assembly method for an electric power steering apparatus according to claim 9, wherein the jig mounting portion is a diameter / change portion formed on the steering shaft and having a diameter changed.   The method of assembling the electric power steering apparatus according to claim 9, wherein the jig mounting portion is a partial plane portion formed on the steering shaft.

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