JPH062858Y2 - Electric power steering device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of use] The present invention relates to an electric power steering device which improves the detection accuracy of steering torque and improves the reliability of the device.

[Prior Art] An electric power steering device capable of fine control according to a running condition of a vehicle is under development as an alternative to a hydraulic power steering device that is widely used.

An example of the electric power steering device that has been conventionally developed is disclosed in Japanese Utility Model Laid-Open No. 60-137339. As shown in FIGS.
Is formed in a tubular shape, and its upper end portion is connected to a steering handle shaft (not shown) via a spline 101. At the bottom of the input shaft 102, the pinion case 10
Steering gear shaft 1 rotatably supported with respect to 3
The upper cylinder part 04 of No. 04 is fitted so that relative rotation is possible. The upper and lower ends of a torsion bar spring 107 are connected to the lower end of the upper tubular portion 105 and the upper end of the input shaft 102 via connecting pins 106, respectively.
5, the driven gear 108 is integrally fitted. A reduction gear connected to an electric motor (not shown) is meshed with the driven gear 108.

Also, an annular slider 110 is rotatable with respect to the input shaft 102 and slidable in the vertical direction (vertical direction in FIG. 6).
Is fitted to the inner peripheral surface of the slider 110,
An annular V groove 113 is formed. The V-shaped groove 113 has a spiral twisted groove hole 11 formed in the input shaft 102.
A plurality of steel balls 112 slidably and tightly held with respect to 1 are in rolling contact with each other. In addition, the cylindrical portion 10
Also on the outer peripheral surface of the upper end of 5, linear V grooves 114 with which the steel balls 112 rollably abut are formed in parallel with the axial direction of the input shaft 102. As a result, the steel ball 112 is twisted in the V-grooves 113 and 114 in the twisted groove hole 1 respectively.
When held inside 11, the relative rotation between the input shaft 102 and the upper cylinder portion 105 causes the steel ball 112 to be displaced in the vertical direction in FIG. 6 along the twist groove hole 111 by the V groove 114. As a result, the slider 110 slides up and down with respect to the input shaft 102.

An annular groove 118 is formed on the outer peripheral surface of the slider 110. The annular groove 118 is swingably supported by a housing 116 via a swing shaft 115 perpendicular to the input shaft 102. It is slidably and tightly engaged with one end of 117. The housing 1 includes a slider 1
A displacement detector 119 for detecting the amount of displacement of 10 is attached, and the detector 120 of this displacement detector 119 is pressed against the other end of the detection lever 117. The displacement detector 119 is for increasing or decreasing the operating current of the electric motor based on the amount of displacement of the slider 110 which is expanded by the detection lever 117.

With such a configuration, when the steering handle shaft is operated to cause relative rotation between the steering gear shaft 104 and the input shaft 102 with the torsion of the torsion rod spring 107, the slider 110 slides along the input shaft 102. The displacement amount is moved by the displacement lever 119 via the detection lever 117.
Detected by. Then, the electric motor operates based on this detection signal to drive the steering gear shaft 104. As a result, the driver can always steer the torsion bar spring 107 at a constant torsion torque or less.

[Problems to be Solved by the Invention] In the conventional electric power steering apparatus disclosed in Japanese Utility Model Laid-Open No. 60-137339, the slider is formed by fitting the steel ball 112 and the V-grooves 113 and 114. The steel ball 112 and the V-grooves 113 and 114 need to be always in contact with each other without any gaps. However, a pair of V-grooves 113 and 114
In a structure in which the steel ball 112 is held by the V-grooves 113 and 114, the positional accuracy of the V-grooves 113 and 114 is generally very delicate.
It is practically impossible unless the position adjusting means for at least one of the grooves 113 and 114 is provided. That is, V
If the depths of the grooves 113 and 114 are too shallow, smooth rolling of the steel balls 112 becomes difficult, resulting in a demand for a large steering force from the driver. On the contrary, if the depth of the V-grooves 113 and 114 is too deep, a gap is formed between the steel ball 112 and the V-grooves 113 and 114, and play is generated in the slider 110, which requires a large steering force for the driver. Not only that, the torsion bar spring 107 may be damaged.

As described above, in the conventional case, in addition to the outer diameter dimension of the upper tubular portion 105 and the inner diameter dimension of the input shaft 102, there is also a relationship of the fitting clearance between the input shaft 102 and the slider 110, which is substantially the same as the slider 110. Inevitably, a large amount of play is inevitable, and the torque detection accuracy is poor and the reliability is poor.

The present invention is intended to solve the above-mentioned problems, and provides an electric power steering device capable of improving the reliability of the device by eliminating rattling by easy setting and improving torque detection accuracy. The purpose is to provide.

[Means for Solving Problems] Therefore, the electric power steering device of the present invention is
A steering wheel shaft is connected to one end, and a steering gear shaft is rotatably fitted to the other end of the steering gear shaft coaxially with the steering wheel shaft, and is coaxial with the center of the input shaft. And a torsion bar spring whose one end is fixed to the input shaft and the other end is fixed to the steering gear shaft, and is integrally provided coaxially with the steering gear shaft so as to surround the input shaft. The driven gear, a tubular slider that is relatively rotatable in the tubular portion of the driven gear, and is slidably fitted along the axial direction of the tubular portion, and is integrally formed on the inner peripheral surface of the slider. It penetrates slidably in a helical twist groove formed in the cylindrical portion of the driven gear and protrudes, and its tip is tightly locked in an engaging groove formed on the outer peripheral surface of the input shaft. Drive pin and above A torque sensor that is connected to the rider and that detects axial movement of the slider that is integral with the drive pin that moves along the twist groove due to relative rotation of the steering handle shaft with respect to the steering gear shaft; Connected to the driven gear and a detection lever that is slidably fitted in an annular groove formed on the outer peripheral surface of the other end and has the other end connected to the torque sensor and rotatably supported at the intermediate part. A driving gear having a driving gear capable of transmitting a driving force to the steering gear shaft and having an electric motor which operates based on a detection signal from the torque sensor, and a penetrating portion of the driving pin into the twisted groove hole; It is characterized in that a roller is attached to the tip end portion that is locked to or the outer circumference of the one end portion of the detection lever.

[Operation] In the above-described electric power steering device of the present invention, when the steering handle shaft is operated, the input shaft causes relative rotation with respect to the steering gear shaft, accompanied by twisting of the torsion bar spring. The slider rotates integrally with the input shaft via the drive pin that is locked in the mating groove. At this time, since the drive pin slides in the axial direction of the input shaft along with the slider along the twist groove formed in the tubular portion of the driven gear, the relative movement between the input shaft and the steering gear shaft is prevented. The amount of sliding of the slider that slides according to the amount of rotation is detected by the torque sensor. Then, the electric motor operates based on the detection signal from the torque sensor, and the steering gear shaft integrated with the driven gear that meshes with the drive gear of the electric motor is rotationally driven.
As a result, the steering force of the driver always remains at a level that allows the relative rotation of the input shaft and the steering gear shaft below a certain level. With the slide of the slider, the tip of the drive pin slides in the engagement groove and the twist groove of the input shaft, and the detection lever slides in the annular groove of the slider. The rollers mounted on these sliding parts facilitate this sliding.

[Embodiment] An electric power steering apparatus as an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view showing the entire structure thereof, and FIG. 2 is a perspective view showing the outer shape of a driven gear thereof. FIG. 3 is a sectional view taken along the line III-III in FIG. 1, FIG. 4 is a perspective view showing the outer shape of the spool, and FIG. 5 is a sectional view showing a roller mounted on the drive pin and the detection lever. .

In the electric power steering apparatus of the present embodiment, as shown in FIG. 1, an input shaft (input shaft) 13 formed in a tubular shape (substantially cylindrical shape) has its upper end protruding from the upper cover 11. It is provided with a steering hand shaft 27 via a spline 26. Also,
The upper end of the input shaft 13 is rotatably supported by the upper cover 11 via a bearing 12.

A steering gear shaft 14 is provided at the lower end of the input shaft 13.
The upper end of the shaft is fitted through a bearing metal 15 so as to be coaxial with the input shaft 13 and to be rotatable relative to the input shaft 13.

An upper portion of the steering gear shaft 14 is rotatably supported by a housing 17 via an angular bearing 16, and a lower portion of the steering gear shaft 14 is rotated by an angular bearing 19 with respect to a pinion case 18. It is supported freely.

Further, the upper cover 11 is integrally connected to the housing 17 by a fixing bolt 20, and the upper cover 11, the housing 17, and the pinion case 18 are positioned at a predetermined position by a through bolt 21 and integrally connected. There is.

The concentricity of the pair of angular bearings 16 and 19 is set so that the fitting portion 22 and the seat portion 23 formed on the housing 17 and the pinion case 18 are within a predetermined tolerance. Also, these angular bearings 1
The preload on 6, 19 can be adjusted by operating the preload adjusting nut 25 screwed to the lower end of the steering gear shaft 14. This preload adjusting nut 25
After the adjustment, it is fixed by a lock nut 24 which is also screwed to the lower end of the steering gear shaft 14.

Inside the input shaft 13, a torsion bar spring 29 is arranged. The torsion bar spring 29 has a pin 28 at its upper end.
Is coaxially connected to the input shaft 13 by the spline 3
The lower end of the steering gear shaft 14 is connected to the steering gear shaft 14 via the shaft 0.

A tubular portion 31 a of a driven gear (driven gear) 31 is integrally fitted to the upper end portion of the steering gear shaft 14 so as to surround the lower portion of the input shaft 13. Further, an electric motor 38 is fixed to the upper cover 11 via mounting bolts 32.

A drive gear (drive gear) 35 meshes with the driven gear 31 via a pair of reduction gears 36 and 37, and the drive gear 35 passes through a spindle 33 a of an electric motor 33 and an electromagnetic clutch 34. It is connected.
The drive gear 35 and the reduction gears 36 and 37 are rotatably supported by the upper cover 11 and the housing 17.

On the other hand, the steering gear 38 formed on the steering gear shaft 14 includes a rack 4 connected to a tie rod 39.
The tie rod 39 is connected to a knuckle arm connected to a wheel (not shown).

Further, a slider 42 formed in a tubular shape is fitted into the tubular portion 31a of the driven gear 31 via a bearing metal 41 so as to be rotatable and slidable in the axial direction of the tubular portion 31a.
The slider 42 is arranged coaxially with the steering gear shaft 14. A drive pin (drive pin) 43 is integrally provided on the slider 42 so as to project inward in the radial direction.

As shown in FIG. 2, the drive pin 43 slidably and tightly penetrates the spiral twisted groove hole (oblique hole) 31b formed in the cylindrical portion 31a, and is connected to the lower end portion of the input shaft 13. The tip of the engaging groove 13a is slidably and tightly engaged with the formed engaging groove 13a.

As shown in FIGS. 1 and 3, an annular groove 42a is formed in the lower portion of the outer peripheral surface of the slider 42, and one end of the detection lever 45 is slidably and tightly fitted in the annular groove 42a. Engaged. Further, a spool 46 is slidably attached to the housing 17 in the axial direction of the input shaft 13, and an annular groove 46a is also formed in the spool 46. The other end of the detection lever 45 is formed in the annular groove 46a. Are slidable and tightly engaged.

At the lower end of the spool 46, a displacement detector 47 as a torque sensor capable of detecting axial displacement (vertical displacement in FIG. 1) of the slider 42 caused by rotation of the slider 42 is provided via a pin 48. Are linked together.

The detection lever 45 is swingably supported by the housing 17 via a swing shaft (lever pin) 44 arranged at a right angle to the axis of the input shaft 13.

Further, as shown in FIG. 4, the spool 46 has a pair of flat notches 46b and 46c which are orthogonal to each other at the central portion and the upper portion of the outer peripheral surface in the longitudinal direction. As shown in FIG. 3, the spool 46 is provided with the notch 4 of the cap for rotation prevention 51 mounted on the housing 17.
By the contact with 6b, its rotation is restricted.

Another notch 46c extending along the longitudinal direction of the spool 46 is used to avoid interference between the spool 46 and the detection lever 45 when the spool 46 is mounted in the housing 17. That is, spool 4
In mounting 6, the spool 46 is inserted into the housing 17 while adjusting the direction of the spool 46 so that the notch 46c and the other end of the detection lever 45 oppose each other, and then the spool 46 is rotated 90 degrees about the axis. Then, as shown in FIGS. 1 and 3, the other end of the detection lever 45 is fitted in the annular groove 46a.

Further, there is rattling generated in the gap between the drive pin 43 and the twist groove 31b, and the detection lever 45 and the annular grooves 42a, 46.
In order to prevent the detection accuracy of the displacement detector 47 from deteriorating due to backlash generated in the gap with the a, a compression coil spring 49 for removing play (with backlash) is provided in the driven gear 31 and the slider 4.
It is interposed between the two. The displacement of the slider 42 is enlarged by the detection lever 45, and the spool 46
Is transmitted to the displacement detector 47 via the.

Then, the detection signal of the displacement detector 47 is sent to a controller (not shown), and in this controller, the electric motor 33
A control signal based on the detection signal is output to the electromagnetic clutch 46.

Under the control of the controller, the electric motor 33 is configured to operate together with the electromagnetic clutch 46 according to the detection signal from the displacement detector 47. In the electric motor 33, the input shaft 1
3, the larger the relative rotation amount between the steering gear shaft 14 and the steering gear shaft 14, that is, the larger the axial displacement (vertical displacement) of the slider 42, the larger the electric power is supplied and the larger the driving torque is generated. Torque is transmitted.

That is, when the displacement detector 47 is in the neutral state in which the displacement of the slider 42 is not detected, the electromagnetic clutch 34 is de-energized, the connection between the drive gear 35 and the spindle 33a is disconnected, and the spindle 33a rotates. When the displacement detector 47 detects the displacement of the slider 42, the spindle 33a is rotated and the electromagnetic clutch 34 is energized to connect the drive gear 35 and the spindle 33a.

For example, when the displacement detector 47 detects the upward displacement of the slider 42, the spindle 33a is normally rotated to transmit the normal rotation force of the spindle 33a to the drive gear 35 via the electromagnetic clutch 34, and the displacement detector 47 is moved. When the downward displacement of 42 is detected, the spindle 33a is reversely rotated and the drive gear 35 is transferred to the spindle 33a via the electromagnetic clutch 34.
It is designed to transmit the reversing force of.

Further, even if the electric motor 33 becomes inoperable for some reason, the lower end portion of the input shaft 13 and the upper end portion of the steering gear shaft 14 are provided so that the rotation from the input shaft 13 can be transmitted to the steering gear shaft 14. The relative rotation restraint portion 50 that restrains the relative rotation amount of the above to a predetermined angle (for example, about 10 degrees) or less is formed. In a normal state, before the relative rotation restraint section 50 is operated, the electric motor 33 is operated so that the relative rotation amount between the input shaft 13 and the steering gear shaft 14 is suppressed to be less than a predetermined angle.

In the electric power steering apparatus according to the present embodiment, the drive pin 43 is engaged with the penetrating portion of the drive pin 43 into the twisted groove hole 31b and the leading end portion of the drive pin 43 engaged with the engagement groove 13a and the annular groove 42a of the slider 42. Rollers 52a, 52b, and 52c are attached to the outer circumferences of the one ends of the detection levers 45 which are fitted together.

As shown in FIG. 5, in each of the rollers 52a, 52b, 52c, a gap 53 having a slight size t (t≈10 μ) is formed between the driving pin 43 and the outer peripheral surface of the detection lever 45. The inner diameter is set as described above, the lubricating oil is supplied into the gap 53, and is slidable with the outer peripheral surfaces of the drive pin 43 and the detection lever 45.

Further, each of these rollers 52a, 52b, 52c has an outer peripheral surface formed into a curved surface having a substantially arcuate cross section, and has a twisted groove hole 31b and an engagement groove 13a, respectively.
And the annular groove 42a is in contact with a minute area such as a point contact.

The rollers 52a, 52b, 52c are made of hardened steel such as hardened steel or hard ceramic, which is hard and has high strength against twisting.

Since the electric power steering apparatus as one embodiment of the present invention is configured as described above, when the steering handle shaft 27 is rotated by operating the steering handle (not shown), the input shaft 13 becomes the steering gear shaft 14 In contrast, the torsion bar spring 29 causes relative rotation accompanied by twisting.

Along with this, the slider 42 rotates integrally with the input shaft 13 via the drive pin 43 that is locked in the engagement groove 13a of the input shaft 13, but at this time, the drive pin 43 is
The slider 42 also slides along with the drive pin 43 in the axial direction of the input shaft 13 along the twist groove 31b formed in the first cylindrical portion 31a. Therefore, the slider 4
2 and the drive pin 43 will spirally rotate around the cylindrical portion 31a.

The detection lever 45 is provided in the annular groove 42a of the slider 42.
Since one end of the detection lever 45 is engaged, the detection lever 45 swings around the swing shaft 44 as the slider 42 moves in the axial direction.

Then, the displacement of the slider 42 is enlarged by the detection lever 45 and transmitted to the displacement detector 47 via the spool 46. The displacement detector 47 detects the sliding amount (displacement amount) of the slider 42, and a detection signal of this displacement amount, that is,
The detection signal of the steering torque is sent to a controller (not shown). Then, a control signal based on the detection signal is output from the controller to the electric motor 33 and the electromagnetic clutch 46.

With the control signal from this controller, the electric motor 33 responds to the detection signal from the displacement detector 47 by the electromagnetic clutch 46.
Works with. For example, in the electric motor 33, the input shaft 13
When the relative rotation amount between the steering gear shaft 14 and the steering gear shaft 14 is large, that is, the axial displacement (vertical displacement) of the slider 42 is large, a large amount of electric power is supplied to generate a large driving torque, and the steering gear shaft 14 is large. Torque is transmitted.

Specifically, when the displacement detector 47 is in the neutral state in which the displacement of the slider 42 is not detected, the electromagnetic clutch 34 is de-energized, the connection between the drive gear 35 and the spindle 33a is disconnected, and the spindle 33a is disconnected. Stops its rotation.

When the displacement detector 47 detects the displacement of the slider 42, the spindle 33a is rotated and the electromagnetic clutch 34 is energized to connect the drive gear 35 and the spindle 33a. In this case, for example, when the displacement detector 47 detects the upward displacement of the slider 42, the spindle 33a is normally rotated according to the upward displacement amount, and the spindle 33a is transferred to the drive gear 35 via the electromagnetic clutch 34.
The forward rotation force of a is transmitted. When the displacement detector 47 detects the downward displacement of the slider 42, the spindle 33
a is reversed according to the amount of downward displacement, and the electromagnetic clutch 34
The reverse rotation force of the spindle 33a is transmitted to the drive gear 35 via.

Therefore, these electric motor 33 and electromagnetic clutch 3
By the operation of 4, the rotational force transmitted from the spindle 33a to the drive gear 35 is transmitted from the drive gear 35 to the driven gear 31 and the steering gear shaft 14 integrated with the driven gear 31 via the reduction gear, A tie rod 39 and a knuckle arm (not shown) are driven from a steering gear 38 formed on the steering gear shaft 14 via a rack 40, so that a wheel (not shown) rolls by a predetermined amount.

As a result, the driver's steering force always remains at a level that allows relative rotation between the input shaft 13 and the steering gear shaft 14 at a certain angle (about 10 degrees) or less.

Then, the tip end portion of the drive pin 43 which is displaced along with the displacement of the slider 42 slides along the engagement groove 13a of the input shaft 13 and the twisted groove hole 31b of the driven gear 31, and the detection lever 45 causes the annular shape of the slider 42. Although it slides in the groove 42a, in the present electric power steering device, since the rollers 52a, 52b, and 52c are attached to these sliding portions, the sliding becomes extremely smooth.

That is, the drive pin 43, when sliding, moves the driven gear 31.
In addition to the frictional force received from the twisted groove hole 31b of the input shaft 13 and the engagement groove 13a of the input shaft 13, particularly, the driving pin 43 receives the urging force received from the compression coil spring 49 for removing play via the slider 42. The frictional force becomes great. Therefore, the drive pin 43 receives a large amount of twist (twisting force), but when the driven pin 31 twists from the twisted groove hole 31b, the roller 52a and the input shaft 1
The engagement groove 13a of 3 and the roller 52b
However, since each is absorbed while rotating, the transmission of each prying to the drive pin 43 is prevented.

Further, the detection lever 45 receives a frictional force from the annular groove 42a of the slider 42 by also assisting the non-biasing force of a return spring (not shown) in the displacement detector 47. For this reason, the detection lever 45 also receives a large amount of prying, but since the roller 52c absorbs this prying while rotating, transmission of the prying to the detecting lever 45 is prevented.

That is, each of these rollers 52a, 52b, 52c has a gap 53 of a slight size between the outer peripheral surface of the drive pin 43 and the detection lever 45, and slides on the outer peripheral surface of the drive pin 43 and the detection lever 45. In addition, the outer peripheral surface is formed into a curved surface having a substantially arcuate cross section, and the spiral groove hole 31b, the engaging groove 13a, and the annular groove 42 are formed, respectively.
Since it is in contact with a in a small area, each roller 52
Even if the a, 52b, and 52c are twisted, the transmission of the twist to the drive pin 43 and the detection lever 45 is prevented.

Then, by setting the outer diameters of the rollers 52a, 52b, 52c in correspondence with the inner diameters of the spiral groove hole 31b, the engaging groove 13a, and the annular groove 42a, it is possible to eliminate rattling of the sliding portion. Therefore, the torque detection accuracy can be easily improved, and the device can be made highly reliable.

[Effect of the Invention] As described in detail above, according to the electric power steering apparatus of the present invention, the tip end portion is slidably penetrated through the inner peripheral surface of the slider through the twist groove hole of the cylindrical portion of the driven gear. Is provided with a drive pin body that tightly locks in the engagement groove of the input shaft, and one end of which is provided with a detection lever that is slidably fitted in an annular groove on the outer peripheral surface of the slider. The outer diameter of the roller can be adjusted by changing the outer diameter of the roller through the penetrating portion into the twisted groove hole, the tip end engaging with the engagement groove, or the outer periphery of the one end of the detection lever. By setting the inner diameters of the groove or the annular groove in correspondence with each other, it is possible to eliminate rattling of the sliding portion and realize smooth sliding. As a result, there is an effect that the dimensional control of the parts and the assembly accuracy are not required to be strict as in the conventional case, the torque detection accuracy can be easily improved, and the device can be made highly reliable.

[Brief description of drawings]

1 to 5 show an electric power steering apparatus as an embodiment of the present invention. FIG. 1 is a sectional view showing the entire structure thereof, and FIG. 2 is a perspective view showing the outer shape of a driven gear thereof. FIG. 3 is a sectional view taken along the line III-III in FIG. 1, FIG. 4 is a perspective view showing the outer shape of the spool, and FIG. 5 is a sectional view showing a roller attached to the drive pin and the detection lever. 6 and 7 show a conventional electric power steering apparatus, FIG. 6 is a sectional view showing the structure of the main part thereof, and FIG. 7 is a sectional view taken along the line VII-VII in FIG. 11 ... Top cover, 12 ... Bearing, 13 ... Input shaft (input shaft), 13a ... Engagement groove, 14 ... Steering gear shaft, 15 ... Bearing metal, 16 ... Angular bearing, 17
... Housing, 18 ... Pinion case, 19 ... Angular bearing, 20 ... Fixing bolt, 21 ... Penetration bolt, 22 ...
Pinion case fitting portion, 23 ... Pinion case seat portion, 24 ... Lock nut, 25 ... Preload adjusting nut, 26
… Splines, 27… Steering handle shafts, 28…
Pin, 29 ... Torsion rod spring, 30 ... Spline, 31 ...
Driven gear (driven gear), 31a ... Cylinder of driven gear,
31b ... Helical spiral groove hole (oblique hole), 32 ... Mounting bolt, 33 ... Electric motor, 33a ... Electric motor spindle, 34
… Electromagnetic clutch, 35… Drive gear, 3
6, 37 ... Reduction gear, 38 ... Steering gear, 39 ...
Tie rod, 40 ... Rack, 41 ... Bearing metal, 42 ...
Slider, 42a ... Annular groove, 43 ... Drive pin (drive pin), 44 ... Oscillation shaft (lever pin), 45 ... Detection lever, 46 ... Spool, 46a ... Annular groove, 46b, 46c
... flat notch, 47 ... displacement detector as torque sensor, 48 ... pin, 49 ... compression coil spring for removing play (rattle), 50 ... relative rotation restraint portion, 51 ... anti-rotation cap, 52a , 52b, 52c ... Rolls, 53 ... Gap between inner circumference of rollers and outer circumference of drive pin or detection lever.

Claims (1)

[Scope of utility model registration request] 1. A cylindrical input shaft having a steering handle shaft connected to one end and a steering gear shaft rotatably fitted to the other end coaxially with the steering handle shaft. A torsion rod spring provided coaxially in the central portion, one end of which is fixed to the input shaft and the other end of which is fixed to the steering gear shaft, and a coaxial shaft with the steering gear shaft that surrounds the input shaft. In this state, a driven gear integrally provided with the driven gear, a tubular slider that is relatively rotatable with respect to the tubular portion of the driven gear, and is slidably fitted along the axial direction of the tubular portion; A spiral twist groove hole formed integrally on the peripheral surface and formed in the cylindrical portion of the driven gear is slidably pierced, and a tip portion thereof is engaged with an engaging groove formed on the outer peripheral surface of the input shaft. Drive that locks tightly And a torque sensor connected to the slider and for detecting axial movement of the slider that is integral with the drive pin that moves along the twisted groove hole due to relative rotation of the steering handle shaft with respect to the steering gear shaft; A detection lever whose part is slidably fitted in an annular groove formed on the outer peripheral surface of the slider, the other end of which is connected to the torque sensor and which is rotatably supported at an intermediate part; and the driven gear. And a motor that has a drive gear that can transmit a driving force to the steering gear shaft and that operates based on a detection signal from the torque sensor, and a penetrating portion of the drive pin into the twist groove, An electric power steer, characterized in that a roller is attached to the tip end engaged with the engagement groove or the outer circumference of one end of the detection lever. Packaging equipment.