CN115503813A - Electric power steering device and vehicle with same - Google Patents

Abstract

The invention provides an electric power steering apparatus and a vehicle having the same, the electric power steering apparatus including: two electric power steering units and a wire control unit; the two electric power steering parts are symmetrical relative to a first direction, the output ends of the two electric power steering parts are coaxially arranged along a second direction perpendicular to the first direction, and the wire control part is in communication connection with the two electric power steering parts; the steer-by-wire section is configured to transmit a steering control signal, the electric power steering section input is configured to turn according to the acquired steering control signal, and the electric power steering section output is configured to move in the second direction. The invention can realize pure electric steering, is suitable for the light-weight and flexible automatic driving steering control of the front independent suspension.

Description

Electric power steering device and vehicle with same

Technical Field

The present invention relates to the field of automatic driving technologies, and in particular, to an electric power steering apparatus and a vehicle having the same.

Background

Most of steering systems of existing medium and heavy commercial vehicles are matched with hydraulic power-assisted steering by non-independent suspension steering transmission mechanisms, and few passenger vehicles and special equipment vehicles adopt the independent suspension steering transmission mechanisms to be matched with the hydraulic power-assisted steering.

However, at present, both the non-independent suspension steering transmission mechanism and the independent suspension steering transmission mechanism have a plurality of defects, for example, the non-independent suspension steering transmission mechanism adopts an integral front axle, and the structural part has heavy weight; for example, the existing pure electric circulating ball steering gear has insufficient output torque and can not meet the steering requirement of the heavy commercial vehicle with the independent suspension; for example, the existing steering transmission mechanism is suitable for the fixed coordinated movement of the wheels at the left side and the right side of a steering axle, and the steering modes such as 'crab running' driving and the like can not be realized.

Disclosure of Invention

In view of the above, it is desirable to provide an electric power steering apparatus and a vehicle having the same.

The present invention provides an electric power steering apparatus, including:

the two electric power steering parts are symmetrical relative to a first direction, and the output ends of the two electric power steering parts are coaxially arranged along a second direction which is vertical to the first direction; and

the drive-by-wire part is in communication connection with the two electric power steering parts;

the drive-by-wire section is configured to transmit a steering control signal; the electric power steering part input end is configured to rotate according to the acquired steering control signal; the electric power steering output is configured to move in the second direction.

In one embodiment, the line control unit includes:

a first line control sub-section connected in series communication with the two electric power steering sections; and

a second linear sub-portion in parallel communication with the two electric power steering portions, the second linear sub-portion configured to transmit a steering control signal.

In one embodiment, the second linear control sub-portion is configured to send a first steering control signal to one of the electric power steering sections; the first linear control sub-section is configured to send the first steering control signal to the other electric power steering section.

In one embodiment, the first linear control sub-section is configured to verify communication between the two electric power steering sections; the second linear control sub-section is configured to send a second steering control signal and a third steering control signal to the two electric power steering sections, respectively.

In one embodiment, the electric power steering unit includes:

a steering drive sub-section, the steering drive sub-section input end being configured to convert a rotational motion about a third direction into a linear motion along the third direction according to the steering control signal obtained; the steering driver sub-portion output end is configured to convert linear motion along the third direction into rotational motion around the first direction; wherein the third direction is perpendicular to the first direction and the second direction;

the input end of the transmission sub-part is pivotally connected with the output end of the steering driving sub-part; the transmission sub-portion is configured to convert a rotational motion about a direction perpendicular to the third direction into a linear motion along the second direction; and

and the steering knuckle sub part is pivotally connected with the output end of the transmission sub part and moves along with the transmission sub part along the second direction.

In one embodiment, the transmission sub-section includes:

a steering arm, a first end of the steering arm pivotally connected to the output end of the steering drive sub-portion; and

a drag link having a first end pivotally connected to the steering arm second end; the drag link second end is pivotally connected to the knuckle sub-section.

In one embodiment, the steering driving sub-section includes:

a steering torsion bar configured to perform a rotational motion about a third direction according to the acquired steering control signal;

an input shaft coaxially connected with the first end of the steering torsion bar and rotationally moving with the steering torsion bar;

a steering screw coaxially connected with the second end of the steering torsion bar and rotationally moving along with the steering torsion bar;

the steering nut is sleeved on the steering screw rod and is meshed and connected with the steering screw rod, and the steering nut converts the rotary motion around the third direction into the linear motion along the third direction; and

and the steering rocker arm is meshed and connected with the steering nut, and the steering rocker arm converts the linear motion along the third direction into the rotary motion around the first direction.

In one embodiment, the steering driving sub-section further includes:

the sensing end of the torque sensor is respectively connected with the input shaft and the steering screw, and a torque signal is obtained when relative displacement occurs between the input shaft and the steering screw; and

and the controller is in communication connection with the torque sensor and the wire control part, receives a torque signal sent by the torque sensor and sends the torque signal to the wire control part, and the wire control part updates the steering control signal and outputs the updated steering control signal.

In one embodiment, the method further comprises the following steps:

a main pin rotating assembly, wherein a first end of the main pin rotating assembly is coaxially and rotatably connected with the output end of the electric power steering part along a second direction so as to enable the output end of the electric power steering part to rotate around the main pin rotating assembly; and

a crossbar assembly pivotally connected to said kingpin pivot assembly second end, said crossbar assembly pivoting with said kingpin pivot assembly about a third direction perpendicular to said first and second directions.

The invention also provides a vehicle which comprises the electric power steering device and is mainly applied to medium and heavy commercial vehicles.

The two electric power steering parts are symmetrically arranged and are not connected by mechanical hardware, the two electric power steering parts are independently controlled by the wire control part, sufficient steering torque is provided, the light weight requirement is met, various different steering modes are provided, and more flexible steering control is realized.

Drawings

Fig. 1 is a schematic structural diagram of an electric power steering apparatus according to an embodiment of the present invention.

Fig. 2 shows a side sectional structural view of the steering driver sub-section of fig. 1.

Fig. 3 shows a wiring diagram of the steering driving sub-section in the embodiment of the present invention.

Description of the reference symbols:

1000-an electric power steering section;

1100-steering drive sub-section;

1110-a steering torsion bar;

1120-an input shaft;

1130-a steering screw;

1140-a steering nut;

1150-pitman arm;

1160-torque sensor;

1170-a controller;

1171-a first line control interface;

1172-a second line control interface;

1173-controller power interface;

1174-controller internal sensor interface;

1180-housing;

1190-cylindrical pin;

1200-a gearing subsection;

1210-a steering arm;

1220-a drag link;

1300-knuckle subsection;

1310-a knuckle;

1320-knuckle arm;

1400-a suspension sub-portion;

1410-kingpin rotation assembly;

1420-upper cross arm;

1430-lower crossbar;

2000-line control part;

2100-a first line control subsection;

2110-first line control;

2200-a second line control subsection;

2210-vehicle controller;

2220-second line control.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein, as those skilled in the art will recognize without departing from the spirit and scope of the present invention.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and are not to be considered limiting of the invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or to implicitly indicate the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless explicitly specified otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood according to specific situations by those of ordinary skill in the art.

In the present invention, unless otherwise expressly stated or limited, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like as used herein are for illustrative purposes only and do not denote a unique embodiment.

Referring to fig. 1, fig. 1 is a schematic structural diagram of an electric power steering apparatus according to an embodiment of the present invention.

An embodiment of the present invention provides an electric power steering apparatus including: two electric power steering units 1000 and a wire control unit 2000.

The two electric power steering units 1000 are symmetrical with respect to a first direction, and output ends of the two electric power steering units 1000 are coaxially arranged in a second direction perpendicular to the first direction. The wire control unit 2000 is connected to the two electric power steering units 1000 in communication. The wire control section 2000 is configured to transmit a steering control signal; the input end of the electric power steering part 1000 is configured to rotate according to the acquired steering control signal; the output of the electric power steering 1000 is configured to move in a second direction.

In some embodiments, the first direction may correspond to a vehicle traveling direction, and the second direction may correspond to a direction perpendicular to the vehicle traveling direction, and also to a vehicle right-left direction.

The invention adopts the pure electric power-assisted steering, thereby realizing the energy consumption only during the steering and reducing the energy consumption. According to the invention, hydraulic elements such as a hydraulic pump, a hydraulic pipeline and a steering oil tank in the traditional hydraulic steering system are eliminated, so that the risk of hydraulic leakage is reduced. According to the invention, two independent electric power-assisted steering parts are separately arranged, and the motion decoupling and the control are independent, so that the unilateral electric power-assisted steering mode is realized, and the steering modes such as common fixed circle steering and crab-shaped steering are also considered, and the more flexible steering control is realized.

In an embodiment of the present invention, the electric power steering unit 1000 includes: a steering driver sub-portion 1100, a transmission sub-portion 1200, and a knuckle sub-portion 1300.

The input end of the steering driving sub-section 1100 is configured to convert the rotational motion about the third direction into a linear motion along the third direction according to the acquired steering control signal; the output end of the steering driving sub-section 1100 is configured to convert the linear motion in the third direction into a rotational motion around the first direction; wherein the third direction is perpendicular to the first direction and the second direction. The input end of the transmission sub-part 1200 is pivotally connected with the output end of the steering driving sub-part 1100; the transmission sub-portion 1200 is configured to convert a rotational motion about a direction perpendicular to the third direction into a linear motion along the second direction. The knuckle arm 1320 of the knuckle sub-portion 1300 is pivotally connected to the output end of the transmission sub-portion 1200, and the knuckle sub-portion 1300 moves linearly along the second direction with the transmission sub-portion 1200.

Referring to fig. 2, fig. 2 is a side sectional view of the steering driver portion of fig. 1.

In one embodiment, the steering driving sub-portion 1100 may optionally employ an electric recirculating ball steering gear, wherein the steering driving sub-portion 1100 comprises: a steering torsion bar 1110, an input shaft 1120, a steering screw 1130, a steering nut 1140, and a steering rocker arm 1150. The steering torsion bar 1110 is configured to perform a rotational movement about a third direction in accordance with the acquired steering control signal. The input shaft 1120 is coaxially connected to the first end of the steering torsion bar 1110 and is fixed by a cylindrical pin 1190, so that the input shaft 1120 rotates with the steering torsion bar 1110. The steering screw 1130 is coaxially connected to a second end of the steering torsion bar 1110 and rotationally moves with the steering torsion bar 1110. The steering nut 1140 is disposed on the steering screw 1130 and engaged with the steering screw 1130, and the steering nut 1140 converts the rotation motion around the third direction into a linear motion along the third direction. The steering rocker 1150 is engaged with the steering nut 1140, and the steering rocker 1150 converts the linear motion in the third direction into the rotational motion around the first direction.

The steering driving sub-section 1100 further includes: a torque sensor 1160, and a controller 1170. Two magnetic rings of the torque sensor 1160 are respectively connected with the input shaft 1120 and the steering screw 1130, and when the input shaft 1120 and the steering screw 1130 generate relative displacement, torque signals such as torsion angle and torque change generated by the input shaft 1120 and the steering screw 1130 can be measured through the magnetic rings. The controller 1170 is connected to the torque sensor 1160 and the by-wire control unit 2000 in a communication manner, receives the torque signal transmitted from the torque sensor 1160 and transmits the torque signal to the by-wire control unit 2000, and the by-wire control unit 2000 updates the steering control signal and outputs the updated steering control signal.

Alternatively, the controller 1170 may be mounted on the housing 1180 of the steering drive sub-portion 1100, and the controller may be provided with a first line control interface 1171, a second line control interface 1172, a controller power interface 1173, and a controller internal sensor interface 1174. The first wire control interface 1171 and the second wire control interface 1172 are used for connecting with a wire control portion. The controller power interface 1173 is for external power. The controller internal sensor interface 1174 is configured to interface with the torque sensor 1160.

Referring to fig. 3, fig. 3 is a schematic wiring diagram of the steering driving sub-section in the embodiment of the present invention.

In an embodiment of the present invention, the wire control unit 2000 includes: a first line control sub-section 2100 and a second line control sub-section 2200. The first line control sub-section 2100 is connected in series communication with the two electric power steering sections 1000. The second wire control sub-part 2200 is communicatively connected in parallel with the two electric power steering parts 1000, and is configured to transmit a steering control signal.

In one particular embodiment, the first linear control sub-portion may be a first linear control 2210, and the second linear control sub-portion may include a vehicle controller 2210 and a second linear control 2220. The first line control interface 1171 on the controllers 1170 of the two steering drive subsections 1100 are communicatively connected via a first line control 2100. The second wire control interfaces 1172 of the controllers 1170 of the two steering drive subsections 1100 are respectively connected with the whole vehicle controller 2210 in a communication manner through second wire controls 2220. Wherein the first line control 2100 may be a private CAN line. The second line control 2220 may be a public CAN line.

After the electric power steering device is started, communication verification can be performed firstly. Communication verification of one first line control 2100 and two second line controls 2220 in the line control section 2000 is completed. That is, communication verification between the two electric power steering units 1000 is performed through a private CAN line, and if a verification error occurs in one of the electric power steering units 1000, the electric power steering unit exits immediately. The two common CAN lines are used to respectively verify the left steering driver sub-portion 1100 and the whole vehicle controller 2210 and the right steering driver sub-portion 1100 and the whole vehicle controller 2210, and if a verification error occurs, the right steering driver sub-portion is immediately exited. After the communication check is completed, a mode selection, such as crab mode or regular mode, may be performed. Under the crab-shaped mode, the turning angles of the left wheel and the right wheel are required to be kept consistent and equal in real time, the left and the right steering driving sub-parts 1100 are reversely calculated by the vehicle controller, and turning angle control commands (or a second steering control signal and a third steering control signal) are respectively sent to the left steering driving sub-part 1100 and the right steering driving sub-part 1100 through two common CAN lines, so that the wheels on the two sides are driven to rotate. Under the selection of the normal mode, the turning angles of the left and right wheels are required to accord with the ackerman steering relationship, the vehicle controller reversely calculates the left and right steering drive sub-portions 1100, and respectively sends turning angle control commands (or a second steering control signal and a third steering control signal) to the left steering drive sub-portion 1100 and the right steering drive sub-portion 1100 through two common CAN lines, so as to drive the wheels at the two sides to rotate. In this control mode, the two steering driver sub-portions 1100 are not connected to the steering mechanism, and are more suitable for unmanned or steer-by-wire.

It should be noted that the present invention is also applicable to a control mode of the one-sided electric power steering, in which the input end of the one-sided steering driving sub-section 1100 is connected to a steering mechanism (for example, a steering wheel, a steering column, a steering transmission shaft, etc.), and the driver can operate the steering wheel to input a steering control signal, thereby assisting the driver in operating the steering wheel to complete the one-sided steering control signal input. Specifically, the steering mechanism is connected to an input end of the steering drive sub-section 1100 disposed on the left side, and is suitable for a left-hand steering vehicle. Similarly, the steering mechanism is connected to the input end of the steering drive sub-section 1100 disposed on the right side, and is adapted to the right-hand steered vehicle. After the input of the single-side steering control signal (or the first steering control signal) is completed, the two side steering driving sub-portions 1100 are connected through the CAN signal communication provided by the first wire control sub-portion 2100, so as to realize the linkage control of the two side steering driving sub-portions 1100.

In one embodiment, the transmission sub-portion 1200 includes: a steering arm 1210 and a drag link 1220. The first end of the steering arm 1210 is pivotally connected to the rotating shaft of the steering rocker arm 1150 at the output end of the steering driver 1100; a first end of the drag link 1220 is pivotally connected to a second end of the steering arm 1210; the second end of the drag link 1220 is pivotally connected to the knuckle sub-portion 1300, and the drag link 1220 drives the knuckle sub-portion 1300 to move in left and right directions.

In an embodiment of the present invention, the method further includes: the suspension sub-section 1400. One end of the suspension sub-section 1400 performs rotation about the third direction in response to movement in the third direction (up and down), and the electric power steering section output end rotates about the other end of the suspension sub-section 1400.

The suspension sub-section 1400 may include: the main pin rotating assembly 1410, the upper cross arm 1420 and the lower cross arm 1430. The first end of the kingpin rotation assembly 1410 is coaxially and rotatably coupled to the output end of the electric power steering 1000 (i.e., the knuckle 1310) in a second direction, such that the output end of the electric power steering 1000 (i.e., the knuckle 1310) rotates about the kingpin rotation assembly 1410. The cross arm assembly is rotatably connected with the second end of the main pin rotating assembly 1410, and rotates around a third direction along with the main pin rotating assembly 1410.

In one embodiment, the left kingpin rotation assembly 1410 is connected to the left upper traverse 1420 via an upper pin and to the left lower traverse 1430 via a lower pin, and the right kingpin rotation assembly 1410 is connected to the right upper traverse 1420 via an upper pin and to the right lower traverse 1430 via a lower pin to form a quadrilateral mechanism, which swings with the tire jumping up and down.

The invention also provides a vehicle with the electric power steering device, which is mainly applied to medium and heavy commercial vehicles. The front axle load of the medium and heavy commercial vehicle is more than 5000kg, and the output torque requirement of the steering gear is more than 4500Nm under the pivot steering working condition. The hydraulic pressure circulation ball steering gear can satisfy the user demand of well heavy commercial car at present. However, the maximum output torque of the existing electric circulating ball steering gear is about 2500Nm, and the direction cannot be steered due to insufficient output torque under the pivot steering working condition by adopting one electric circulating ball steering gear. The two electric circulating ball steering gears adopted in the invention can meet the use requirements of medium and heavy commercial vehicles.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is specific and detailed, but not to be understood as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent should be subject to the appended claims.

Claims (10)

1. An electric power steering apparatus characterized by comprising:

the two electric power steering parts (1000) are symmetrical relative to a first direction, and the output ends of the two electric power steering parts (1000) are coaxially arranged along a second direction perpendicular to the first direction; and

a wire control unit (2000) that is connected to the two electric power steering units (1000) in a communication manner;

the steer-by-wire section (2000) is configured to transmit a steering control signal; the electric power steering (1000) input is configured to turn according to the acquired steering control signal; the electric power steering (1000) output is configured to move in the second direction.

2. The electric power steering apparatus according to claim 1, wherein the drive-by-wire section (2000) includes:

a first line control sub-unit connected in series communication with the two electric power steering units (1000); and

a second linear sub-portion communicatively connected in parallel with the two electric power steering portions (1000), the second linear sub-portion configured to transmit a steering control signal.

3. The electric power steering apparatus according to claim 2, wherein the second linear control sub-section is configured to send a first steering control signal to one of the electric power steering sections (1000); the first line control sub-section is configured to send the first steering control signal to another one of the electric power steering sections (1000).

4. The electric power steering apparatus according to claim 2, wherein the first line control sub-section is configured to verify communication between the two electric power steering sections (1000); the second linear control sub-section is configured to send a second steering control signal and a third steering control signal to the two electric power steering sections (1000), respectively.

5. The electric power steering apparatus according to claim 1, characterized in that the electric power steering section (1000) includes:

a steering drive sub-section (1100), wherein the input end of the steering drive sub-section (1100) is configured to convert the rotation motion around a third direction into the linear motion along the third direction according to the acquired steering control signal; the output end of the steering driving sub-part (1100) is configured to convert the linear motion along the third direction into the rotary motion around the first direction; wherein the third direction is perpendicular to the first direction and the second direction;

the input end of the transmission sub-part (1200) is pivotally connected with the output end of the steering driving sub-part (1100); the transmission sub-section (1200) is configured to convert a rotational motion about a direction perpendicular to the third direction into a linear motion along the second direction; and

the steering knuckle sub-portion (1300) is pivotally connected with the output end of the transmission sub-portion (1200), and the steering knuckle sub-portion (1300) moves along with the transmission sub-portion (1200) along the second direction.

6. The electric power steering apparatus according to claim 5, wherein the transmission subsection (1200) includes:

a steering arm (1210), wherein a first end of the steering arm (1210) is pivotally connected with an output end of the steering driving sub-part (1100); and

a drag link (1220), a first end of the drag link (1220) being pivotally connected to a second end of the steering arm (1210); the drag link (1220) is pivotally connected at a second end to the knuckle sub-portion (1300).

7. The electric power steering apparatus according to claim 5, wherein the steering drive sub-section (1100) includes:

a steering torsion bar (1110) configured to perform rotational movement about a third direction in accordance with the acquired steering control signal;

an input shaft (1120) coaxially connected to a first end of the steering torsion bar (1110) and rotationally moved with the steering torsion bar (1110);

a steering screw (1130) coaxially connected to a second end of the steering torsion bar (1110) and rotationally moved with the steering torsion bar (1110);

the steering nut (1140) is sleeved on the steering screw rod (1130) and is meshed and connected with the steering screw rod (1130), and the steering nut (1140) converts the rotary motion around the third direction into the linear motion along the third direction; and

and the steering rocker arm (1150) is in meshed connection with the steering nut (1140), and the steering rocker arm (1150) converts the linear motion along the third direction into the rotary motion around the first direction.

8. The electric power steering apparatus according to claim 7, wherein the steering driver sub-section (1100) further includes:

a torque sensor (1160), wherein the sensing end of the torque sensor (1160) is respectively connected with the input shaft (1120) and the steering screw (1130), and a torque signal is obtained when the input shaft (1120) and the steering screw (1130) are subjected to relative displacement; and

and a controller (1170) which is in communication connection with the torque sensor (1160) and the drive-by-wire unit (2000), receives a torque signal transmitted by the torque sensor (1160) and transmits the torque signal to the drive-by-wire unit (2000), and the drive-by-wire unit (2000) updates the steering control signal and outputs the updated steering control signal.

9. The electric power steering device according to any one of claims 1 to 8, characterized by further comprising:

a kingpin rotation assembly (1410), wherein a first end of the kingpin rotation assembly (1410) is coaxially and rotatably connected with an output end of the electric power steering (1000) along a second direction, so that the output end of the electric power steering (1000) rotates around the kingpin rotation assembly (1410); and

a crossbar assembly pivotally coupled to said second end of said kingpin pivot assembly (1410), said crossbar assembly pivoting with said kingpin pivot assembly (1410) in a third direction perpendicular to said first and second directions.

10. A vehicle characterized by comprising the electric power steering apparatus according to any one of claims 1 to 9.

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