Angle locking mechanism of steering system and hand feeling simulation device

Abstract

The invention discloses an angle locking mechanism of a steering system. The angle locking mechanism comprises a shell, a driving wheel, a driven wheel, a sliding block and a limiting feature. The driven wheel is provided with a pinion and a cam, the driving wheel is provided with an inner gear, and the inner gear and the pinion form a gear pair; the driving wheel is driven by an external driving shaft to rotate around the first rotating shaft; the driven wheel is driven by the driving wheel to rotate around the second rotating shaft; the cam is driven by the pinion to rotate around the second rotating shaft, and the cam and the driven wheel have the same angular velocity when rotating; the limiting feature is driven by the driving wheel to rotate around the first rotating shaft, and the limiting feature and the driving wheel have the same angular velocity during rotation; the sliding block is provided with a locking end and an arc-shaped end, and the arc-shaped end is in contact with the cam; when the arc-shaped end makes contact with the far rest position or the near rest position of the cam, the limiting feature is attached to the locking end, and a locking position is formed.

Description

Technical Field

[0001] The invention relates to the technical field of automobile steering systems, and in particular to an angle locking mechanism and a hand feeling simulation device of a wire-controlled steering system. Background Art

[0002] In traditional steering systems, the steering wheel torque is transmitted through the column-intermediate shaft and acts on the rack of the steering gear, and the limit lock is achieved when the rack reaches the end of the stroke. In the wire-controlled steering system, since the mechanical connection between the column and the steering gear is cancelled, the steering wheel can rotate without limit, affecting driving safety, so it is necessary to add an angle locking mechanism to the rotation angle of the steering wheel. In addition, due to the lack of the intermediate shaft as a mechanical connection, the steering resistance load cannot be transmitted to the steering wheel, so an additional hand-feel simulation device is required to generate torque to provide mechanical feedback to the driver.

[0003] The concept of a rotation angle locking mechanism for a wire control is known, and the following solutions are available in the industry:

[0004] Solution 1 is gear transmission, which uses multi-stage gears or planetary gear mechanisms to convert multiple rotation angles into smaller angles through deceleration, and set a touch surface at the end to achieve limit. The disadvantage of this solution is that the gear part needs to bear a higher torque load, the tooth surface wear will affect the rotation feel after long-term operation, and the outer envelope size is large;

[0005] The second solution is the thread transmission type, which converts the rotational motion into linear motion through thread transmission and locks it in the linear direction, or converts multiple turns of rotation into radial displacement through a plane Archimedean screw. The disadvantage of this solution is that the end position is easy to self-lock, and the torque is large when reversing.

[0006] Solution 3 is the ferrule type, which uses multiple layers of rotating circles to be stacked radially or axially in series to increase the rotation locking angle range. The disadvantage of this solution is that the middle circle has no reliable constraint and will generate noise when subjected to external impact;

[0007] Option 4 is the intermittent gear type, which converts continuous rotation into intermittent rotation to achieve deceleration. The disadvantage of this option is that the driven teeth need to be constrained when in the free position. If a self-locking feature is added to the driving teeth, higher dimensional accuracy requirements are required when entering or exiting the meshing.

[0008] As mentioned above, the mainstream solutions in the industry are two ways: whether there is a reduction mechanism with a transmission ratio greater than 1. If there is no reduction mechanism, the multi-turn rotation stroke is converted into axial or radial displacement; if there is a reduction mechanism, the multi-turn rotation stroke passes through the reduction mechanism to reduce the angular stroke of the locking position. Summary of the invention

[0009] In order to solve the above technical problems, the present invention provides an angle locking mechanism of a steering system, comprising a housing, a driving wheel, a driven wheel, a sliding block and a limiting feature; the driven wheel is provided with a pinion and a cam, the driving wheel is provided with an internal gear, and the internal gear and the pinion form a gear pair;

[0010] The driving wheel is driven by an external driving shaft to rotate around the first rotating axis; the driven wheel is driven by the driving wheel to rotate around the second rotating axis; the cam is driven by a pinion to rotate around the second rotating axis, and the cam and the driven wheel have the same angular velocity when they rotate; the limiting feature is driven by the driving wheel to rotate around the first rotating axis, and the limiting feature and the driving wheel have the same angular velocity when they rotate;

[0011] The sliding block has a locking end and an arcuate end, and the arcuate end contacts the cam; when the arcuate end contacts the far rest position or the near rest position of the cam, the limiting feature fits with the locking end to form a locking position.

[0012] Preferably, at the locking position, the locking angle of the limiting feature satisfies θ′=±(n*360°+θ1-T3 / 2), where θ′ is the locking angle, n is the number of rotations of the driving wheel, θ1 is the initial phase angle of the limiting feature, and T3 is the occupied angle of the limiting feature.

[0013] Preferably, the profile of the cam is a symmetrical structure; the cam, the sliding block, the driving wheel and the limiting feature are symmetrical relative to the connecting line structure of the first rotating shaft and the second rotating shaft.

[0014] Preferably, a countersunk hole is provided at the upper end of the shell, and a positioning column and a slide groove are provided at the bottom; the driving wheel is installed on the countersunk hole, and the driving wheel is provided with an introduction hole, and the introduction hole, the outer circle of the driving wheel and the inner circle of the countersunk hole are coaxial, and the axis is the first rotating axis; after the external driving shaft is connected to the introduction hole, it drives the driving wheel to rotate in the countersunk hole, and an internal gear is provided at the bottom of the driving wheel, and a limiting feature is provided below the internal gear; a hole is provided in the middle of the driven wheel, which passes through the positioning column and is installed on the bottom surface of the shell; a pinion is provided above the driven wheel, and a cam is provided below, and the pinion is coaxial with the cam, and the axis is the second rotating axis; a retaining spring is fixedly arranged above the positioning column to limit the driven wheel axially, and a sliding block is installed at the bottom of the shell, located on the side of the driven wheel, and the sliding block is also located in the slide groove, and can make radial movement in the slide groove.

[0015] Preferably, the angle locking mechanism further comprises a spring; the spring is installed in a recessed groove at the bottom of the shell, and a hanging platform is provided at the bottom of the sliding block, and the hanging platform compresses the spring when the sliding block moves radially outward.

[0016] Preferably, the locking end and the arcuate end of the sliding block are connected; when the middle position of the far repose angle of the cam contacts the arcuate end of the sliding block, the sliding block is at the farthest radial movement distance, and the limiting feature is located on the center line of the near repose angle of the cam.

[0017] Preferably, the arcuate end of the sliding block is a cylindrical structure, the profile of the cam is a ring groove track, the cam and the arcuate end form a cam pair, the inner profile of the cam applies force during the push stroke, and the outer profile of the cam applies force during the return stroke.

[0018] Preferably, the slide groove is located outside the shell; the locking end and the arc end of the sliding block are not connected; when the middle position of the cam near the repose angle contacts the arc end of the sliding block, the sliding block is at the shortest radial movement distance, and the limiting feature is located on the center line of the cam far repose angle.

[0019] Preferably, the angle locking mechanism includes a bearing and a gear shaft; a bearing is installed under the shell, and the gear shaft passes through the bearing and rotates around the first rotating shaft; the driving wheel is installed and fixed above the gear shaft, and the internal gear is fixed on the driving wheel; a retaining spring is provided above the driving wheel and installed on the gear shaft; the driving wheel has the same axis as the internal gear and the gear shaft, and has the same angular velocity of rotation, and the axis is the first rotating shaft; a sink groove and a slide groove are provided at the bottom of one side of the shell, and the sliding block is provided with a hanging platform and a slide plate, the hanging platform is located inside the sink groove, and the slide plate is located on the bottom surface of the slide groove and slides for radial movement; the driving wheel is fitted with the slide plate above the bottom; two limiting features are provided on the driving wheel; a countersunk hole is also provided above the shell, and the driven wheel is installed on the countersunk hole, and a pinion and a cam are provided on the driven wheel, the cam is in the shape of a cam profile annular groove, the pinion is coaxial with the cam and the outer ring of the driven wheel, and rotates together around the axis of the sink hole, and has the same angular velocity, and the axis is the second rotating shaft.

[0020] Preferably, the arc-shaped end of the sliding block is in the shape of a cylinder.

[0021] Preferably, an end cover is further provided above the driven wheel, and the end cover is fixed in the housing to limit the axial position of the driven wheel.

[0022] Preferably, when the intermediate position near the rest point of the cam contacts the arc-shaped end of the sliding block, the sliding block is at the shortest radial movement distance.

[0023] Preferably, the design method of the parameters of the driving wheel, the driven wheel, the cam, the sliding block and the limiting feature in the angle locking mechanism is:

[0024] Step S1, determining the maximum outer diameter of the driving wheel and the pitch circle diameter of the internal gear according to the envelope size and the maximum load torque constraint;

[0025] Step S2, setting the gear ratio of the gear pair;

[0026] Step S3, setting the maximum push stroke and movement angle of the cam;

[0027] Step S4, checking whether the maximum contact pressure angle of the cam pair is self-locking, if not self-locking, proceeding to step S5, if self-locking, returning to step S3, resetting the maximum push stroke and movement angle of the cam;

[0028] Step S5, check the strength of the limit feature, if it meets the requirements, proceed to step S6, if it does not meet the requirements, return to step S3, and reset the maximum push stroke and movement angle of the cam;

[0029] Step S6, checking the locking angle of the angle locking mechanism when locked according to the gear ratio and the movement cycle of the sliding block, if the locking angle meets the preset angle range, the process ends, otherwise, step S2, resetting the gear ratio of the gear pair.

[0030] The present invention also provides a steering system hand feel simulation device, including a power unit, a reduction gear box and an angle locking mechanism; the angle locking mechanism is installed at the bottom of the reduction gear box, and the power unit generates the required torque under the specification of an internal controller, which acts on the gear shaft, the upper end of the gear shaft is connected to the steering column, and the lower end of the gear shaft is connected to the driving wheel of the angle locking mechanism; the angle locking mechanism is as described above.

[0031] The mechanism of the present invention has few overall parts; it can be designed as an integrated or split structure, and as a split structure, the function can be realized after being externally connected to a feel module, which is simple and quick; when unloaded, the overall rotational torque and internal friction load of the mechanism are small, the operation process is smooth, and the impact on the feel is small; the transmission mechanism and the locking mechanism are two parts and do not affect each other; the transmission mechanism does not carry any load, and the gears and cam pairs can be designed as split types, such as plastic parts, thereby reducing costs; the limiting feature has a large rotation radius and good load-bearing capacity, and can withstand a large torque load. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments:

[0033] Figure 1 This is a schematic diagram of the angle locking mechanism structure of Example 1;

[0034] Figure 2 A schematic diagram of a method for designing parameters of an angle locking mechanism according to Embodiment 1;

[0035] Figure 3 This is a schematic diagram of the first locking principle of Example 1;

[0036] Figure 4 This is a schematic diagram of the second locking principle of Example 1;

[0037] Figure 5 This is a geometric relationship diagram of various components in the angle locking mechanism of Example 1;

[0038] Figure 6This is a schematic diagram of the angle locking mechanism structure of Example 2;

[0039] Figure 7 This is a structural schematic diagram of the angle locking mechanism of Example 2 without installing a driving wheel;

[0040] Figure 8 A cross-sectional view of the angle locking mechanism of Example 2 Figure 1 ;

[0041] Fig. 9 A cross-sectional view of the angle locking mechanism of Example 2 Figure 2 ;

[0042] Fig.10 This is a structural schematic diagram of the locking position of the angle locking mechanism of Example 2;

[0043] Fig.11 This is a structural schematic diagram of the angle locking mechanism of Example 3 without installing a driving wheel;

[0044] Fig.12 A cross-sectional view of the angle locking mechanism of Example 3 Figure 1 ;

[0045] Fig.13 A cross-sectional view of the angle locking mechanism of Example 3 Figure 2 ;

[0046] Fig.14 This is a structural schematic diagram of the locking position of the angle locking mechanism of Example 3;

[0047] Fig.15 A cross-sectional view of the angle locking mechanism of Example 4 Figure 1 ;

[0048] Fig.16 A cross-sectional view of the angle locking mechanism of Example 4 Figure 2 ;

[0049] Fig.17 A cross-sectional view of the angle locking mechanism of Example 5 Figure 1 ;

[0050] Fig.18 A cross-sectional view of the angle locking mechanism of Example 5 Figure 2 ;

[0051] Fig.19 This is a structural schematic diagram of the locking position of the angle locking mechanism of Example 5;

[0052] Fig. 20 A cross-sectional view of the hand feeling simulation device of Example 6

[0053] Description of Reference Numerals

[0054] 1—angle locking mechanism, 2—reduction gearbox, 3—fastener, 4—power unit, 5—end cover, 11—housing, 12—driving wheel, 13—driven wheel, 14—circlip, 15—sliding block, 16—spring, 111—fixing hole, 112—counterbore, 113—positioning column, 114—counterbore, 115—slideway, 121—introduction hole, 122—internal gear, 123—limiting feature, 131—pinion, 132—cam, 151—hanging platform, 152—locking end, 153—arc end, 154—slide plate, 21—box, 22—gear shaft, 23—bearing, O1—first rotating shaft, O2—second rotating shaft, M—radial direction, R—radial distance, R1—closest in radial direction, R2—farthest in radial direction, θ—rotation angle, θ1—initial phase angle of limit feature, θ2—initial phase angle of cam, θ′—locking angle, T1—rotation period of limit feature, T2—rotation period of sliding block, T3—occupancy angle of limit feature, T4—far rest angle, T5—near rest angle, α—pressure angle, R a —Near rest radius, R b —Far rest radius, R c —Pinion circle radius, R d —Internal gear pitch circle radius, h—gear center distance, S—maximum push stroke, A1—gear pair, A2—cam pair, A3—locking position, A4—driving position. DETAILED DESCRIPTION

[0055] The following describes the implementation methods of the present invention through specific specific embodiments, and those skilled in the art can fully understand other advantages and technical effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through different specific implementation methods, and the details in this specification can also be applied based on different viewpoints, and various modifications or changes can be made without deviating from the overall design concept of the invention. It should be noted that the following embodiments and the features in the embodiments can be combined with each other in the absence of conflict. The following exemplary embodiments of the present invention can be implemented in a variety of different forms and should not be interpreted as being limited to the specific embodiments described herein. It should be understood that these embodiments are provided to make the disclosure of the present invention thorough and complete, and to fully convey the technical solutions of these exemplary specific embodiments to those skilled in the art.

[0056] Example 1

[0057] like Figure 1 As shown, this embodiment provides an angle locking mechanism of a steering system, comprising a housing 11, a driving wheel 12, a driven wheel 13, a sliding block 15 and a limiting feature 123; the driven wheel 13 is provided with a pinion 131 and a cam 132, the driving wheel 12 is provided with an internal gear 122, and the internal gear 122 and the pinion 131 form a gear pair;

[0058] The driving wheel 12 is driven by an external driving shaft to rotate around the first rotating axis O1; the driven wheel is driven by the driving wheel to rotate around the second rotating axis O2; the cam 132 is driven by the pinion 131 to rotate around the second rotating axis O2, and the cam 132 has the same angular velocity when rotating as the driven wheel 13; the limiting feature 123 is driven by the driving wheel 12 to rotate around the first rotating axis O1, and the limiting feature 123 has the same angular velocity when rotating as the driving wheel 12; in order to increase the torque bearing capacity, the limiting feature 123 is located at the bottom of the inner gear 122 to obtain the maximum rotation radius.

[0059] The sliding block 15 has a locking end and an arcuate end, and the arcuate end contacts the cam 132 ; when the arcuate end contacts the distal rest position or the proximal rest position of the cam 132 , the limiting feature 123 fits with the locking end to form a locking position.

[0060] The number of teeth on the inner gear is Z1, and the number of teeth on the pinion is Z2, so the transmission ratio is Z2 / Z1; the sliding block 15 is located on the side of the cam 132, and when the cam rotates, it pushes the sliding block to perform periodic motion along the M direction; one or two limit features can be set, and when the driving wheel rotates a preset angle (i.e., the locking angle), the two sides of a single limit feature or the two limit features respectively contact the sliding block to achieve limit locking.

[0061] In the locking position, the locking angle of the limiting feature satisfies θ′=±(n*360°+θ1-T3 / 2), where θ′ is the locking angle, n is the number of rotations of the driving wheel, θ1 is the initial phase angle of the limiting feature, and T3 is the occupied angle of the limiting feature.

[0062] In order to achieve the above locking angle of the limit feature, it is realized by parameter design of the driving wheel, the driven wheel, the cam, the sliding block and the limit feature. The specific method is as follows: Figure 2 As shown, including:

[0063] Step S1, determining the maximum outer diameter of the driving wheel and the pitch circle diameter of the internal gear according to the envelope size (diameter and height) and the maximum load torque constraint;

[0064] Step S2, setting the gear ratio of the gear pair; the center distance of the gear pair can be obtained, and the maximum outer diameter of the pinion is the maximum outer envelope of the cam.

[0065] Step S3, setting the maximum push stroke and movement angle of the cam;

[0066] Step S4, checking whether the maximum contact pressure angle of the cam pair is self-locking, if not self-locking, proceeding to step S5, if self-locking, returning to step S3, resetting the maximum push stroke and movement angle of the cam;

[0067] Step S5, check the strength of the limit feature, if it meets the requirements, proceed to step S6, if it does not meet the requirements, return to step S3, and reset the maximum push stroke and movement angle of the cam;

[0068] Step S6, check the locking angle of the angle locking mechanism when it is locked according to the gear ratio and the movement cycle of the sliding block (i.e. whether the required angle range is met when it is locked for the first time). If the locking angle meets the preset angle range, the process ends. Otherwise, step S2, reset the gear ratio of the gear pair and perform the next round of calculation.

[0069] The locking principles can be divided into the following two types:

[0070] The first locking principle involves that when the arc end contacts the far rest position of the cam, the limit feature fits with the locking end to form a locking position. Figure 3 As shown, taking any rotation direction and setting only a single limit feature as an example, the horizontal coordinate θ is the rotation angle, the vertical coordinate R is the radial distance, and the locking limit position (contact position) is the zero point. When the limit feature does not pass through the locking position, the radial distance R is simplified to 0. When passing through the locking position, the maximum radial distance is R2, and the rotation period is T1, where T3 is the angle occupied by the limit feature; the sliding block produces radial outward displacement as the cam rotates. There is no radial displacement at the near rest position of the cam, and the radial distance is R1. The radial outward displacement is the largest at the maximum push stroke of the cam, and the radial distance reaches R2. The maximum push stroke S satisfies, S = R2-R1, the far rest angle of the maximum push stroke is T4, and the movement period of the sliding block is T2, which is the rotation period of the driven wheel; T 1、 The ratio of T2 to the number of gear teeth satisfies: T2 / T1=Z2 / Z1. When the slider is within the near repose angle of the cam, the limit feature can pass freely. When the slider is outside the near repose angle, the limit feature will interfere with it. After several cycles, the limit feature and the slider intersect and contact at θ′ to achieve locking. At any other position, any T3 falls within the near repose angle T5.

[0071] The second locking principle involves that when the arc end contacts the near rest position of the cam, the limit feature fits with the locking end to form a locking position. Figure 4 As shown in the figure, taking any rotation direction and setting only a single limit feature as an example, the rotation period of the limit feature is T1, where T3 is the angle occupied by the limit feature; the sliding block produces radial outward displacement as the cam rotates, there is no radial displacement at the near resting position of the cam, the radial distance is R1, the near resting angle of the cam is T5, the radial displacement is the largest at the maximum thrust of the cam, and the radial distance is R 2， The far repose angle of the maximum push stroke is T4, and the motion period of the sliding block is T2, which is the rotation period of the driven wheel; T 1、T2 and the gear ratio also satisfy: T2 / T1=Z2 / Z1. The slider is within the far repose angle of the cam, and the limit feature can pass freely. The slider is outside the far repose angle of the cam, and the limit feature interferes with it. After several cycles, the limit feature and the slider intersect and contact at θ′ to achieve locking. At any other position, any T3 falls within the far repose angle T4.

[0072] Taking the first locking principle as an example, the geometric relationship is as shown in 5 above. The driving wheel is located inside the housing and is coaxial with the housing. The driving wheel is provided with a limited position feature and an internal gear, and the two rotate around the same axis O1. The cam and the pinion rotate around the same axis O2. c is the radius of the pinion pitch circle, R d is the pitch circle radius of the internal gear, and the distance O1O2 is the transmission center distance h of the gear pair, satisfying h=R d —R c . Radius R of the cam near resting point a The near rest angle covered is T5, and the far rest arc radius of the cam is R b The far repose angle covered is T4, and the cam envelope size satisfies R b <R c The arc length of the limiting feature occupies an angle of T3. The radial length dimension S of the limiting feature is the overlap length after contact with the sliding block. The overlap length is the maximum push stroke of the cam. This dimension affects the strength of the limiting feature and satisfies: S = R b —Ra. The contact pressure angle between the sliding block and the cam is α. Assume that the push stroke after the cam rotates by an angle φ, that is, the radial displacement of the sliding block, is S′, which satisfies: Tanα=(dS' / dφ) / (S'+Ra). In order to prevent the mechanism from self-locking when the cam is running, the pressure angle satisfies φ≤30°. According to the above geometric relationship, under the constraints of the given rotation torque load and the size envelope, the required locking mechanism can be designed by referring to the method of steps S1 to S6.

[0073] In the existing technical solutions, a single or multiple transmission mechanisms are usually used, most of which are reduction mechanisms with a transmission ratio greater than 1, with a specific locking angle as the total operating cycle, and there are shortcomings such as poor hand feel after durability, easy self-locking, and low bearing strength. The angle locking mechanism proposed in this embodiment is that the active part and the driven part are locked after they come into contact after rotating a specific angle. The special thing is that the limit feature and the sliding block always have relative movement until the locking contact; the active part and the driven part have different small rotation cycles. Before locking, the limit feature passes through the limit position (that is, the locking end of the sliding block) several times, but because both are provided with a special initial phase angle and transmission ratio, they are misaligned, so that they finally come into contact after rotating the required angle, that is, the large cycle; the mechanical structure is a closed-loop type, including a limit feature and a driving wheel of a large gear, a small gear and a cam, and a locking sliding block. The limit feature is locked after contacting the locking sliding block; in addition, the gear pair is an internal meshing gear with a transmission ratio less than 1, The envelope size is small; the limit locking angle can be flexibly designed by adjusting the initial phase angle of the limit feature and the gear transmission ratio; the overall parts of the mechanism are few; it can be designed as an integrated and split structure, and the function can be realized after the split structure is connected to the feel module, which is simple and fast; the overall rotational torque and internal friction load of the mechanism are small when unloaded, the operation process is smooth, and the impact on the feel is small; the transmission mechanism and the locking mechanism are two parts and do not affect each other; the transmission mechanism does not carry any load, and the gears and cam pairs can be designed as split types, such as plastic parts, thereby reducing costs; the limit feature has a large rotation radius and good load-bearing capacity, and can withstand large torque loads.

[0074] The angle locking mechanisms of the following embodiments 2 to 4 are split-type.

[0075] Example 2

[0076] This embodiment utilizes the first locking principle and only provides a single limiting feature.

[0077] like Figure 6 to Figure 9As shown, the angle locking mechanism 1 includes a housing 11, a driving wheel 12, a driven wheel 13, a retaining spring 14, a sliding block 15, and a spring 16. A plurality of fixing holes 111 are provided on both sides of the housing 11 for connecting an external mechanism. A countersunk hole 112 is provided at the upper end of the housing 11, and a positioning column 113, a countersunk groove 114, and a sliding groove 115 are provided at the bottom. The driving wheel 12 is mounted on the countersunk hole 112, and the driving wheel 12 is provided with an introduction hole 121. The introduction hole 121, the outer circle of the driving wheel 12, and the inner circle of the countersunk hole 112 are coaxial, that is, the rotation axis O1. After the external driving shaft is connected to the introduction hole 121, the driving wheel 12 is driven to rotate freely in the countersunk hole 112. An internal gear 122 is provided at the bottom of the driving wheel 12, and a limiting feature 123 is also provided below the internal gear 122. To simplify the description, this embodiment only provides one limiting feature 123. When rotating clockwise or counterclockwise, the two side surfaces of the limiting feature are respectively used to contact the two side surfaces of the sliding block 15 to achieve locking. The inner gear 122 and the limiting feature 123 have the same angular velocity. The driven wheel 13 is provided with a hole in the middle, and is installed on the bottom surface of the housing 11 after passing through the positioning column 113. The driven wheel 13 can rotate freely around the positioning column 113. A pinion 131 is provided above the driven wheel 13, and a cam 132 is provided below. The pinion 131 and the cam 132 are coaxial, that is, the rotating shaft O2, and have the same angular velocity. The retaining spring 14 is fixed above the positioning column 113 to axially limit the driven wheel 13. The spring 16 is installed in the sink 114. The sliding block 15 is installed at the bottom of the housing 11, located on the side of the driven wheel 13. The sliding block 15 is also located in the slide groove 115 and can move radially in the slide groove 115. A hanging platform 151 is provided at the bottom of the sliding block 15. When the sliding block 15 moves radially outward, the hanging platform 151 compresses the spring 16. When the sliding block 15 does not move radially outward, the limiting feature 123 does not interfere with the sliding block 15 when it rotates. When the sliding block 15 moves radially outward, the limiting feature 123 interferes with the sliding block 15 and is locked. The main body of the sliding block 15 is provided with a locking end 152 and an arc end 153, which are connected. The pinion 131 and the internal gear 122 cooperate on one side to form a gear pair A1, which is an internal meshing gear with a center distance of O1O2. The cam 132 and the arc end 153 of the sliding block 15 cooperate on the other side to form a cam pair A2. At the same time, the bottom of the cam 132 fits with the top of the hanging platform 151, limiting the axial movement of the sliding block 15.

[0078] Movement principle: Fig. 9This is the initial state of the angle locking mechanism 1. The profile of the cam 132 itself is a symmetrical structure. In particular, the cam 132, the sliding block 15, the driving wheel 12 and the limiting feature 123 are symmetrical structures relative to the line connecting the two axes O1O2. This arrangement can simply achieve the same locking angle of the mechanism in the clockwise and counterclockwise directions. In addition, the phase angle satisfies: the middle position of the far repose angle of the cam 132 contacts the arc-shaped end 153 of the sliding block 15, the sliding block 15 is at the farthest radial movement distance, and the limiting feature 123 is located on the center line of the near repose angle of the cam 132. When the driving wheel 12 rotates, the pinion 131 is driven to rotate through the internal gear 122, and the cam 132 rotates synchronously with the pinion 131. The sliding block 15 moves radially outward when the cam 132 generates a push stroke, and the spring 16 is compressed. When the cam 132 generates a return stroke, the sliding block 15 is reset by the rebound force of the compressed spring. Due to the special profile of the cam and the transmission ratio of the gear, the limiting feature 123 contacts and locks with the locking end 152 of the sliding block at a specific angle.

[0079] Locking status: Fig.10 As shown, this embodiment is in a locking position in a rotation direction. According to the direction shown in the figure, the rotation direction of the driving wheel 12 is counterclockwise, and the arc end 153 contacts the far rest radius of the cam 132, reaching the maximum push stroke. At this time, one side of the limiting feature 123 is in contact with the locking end 152, and the overlapping length is the largest, forming a locking position A3. The locking angular stroke of this embodiment satisfies θ′=±(n*360°+180°-T3 / 2).

[0080] Example 3

[0081] This embodiment utilizes the second locking principle and only provides a single limiting feature.

[0082] like Figure 11-12 As shown, the relative positions of the housing 11, the driving wheel 12, the driven wheel 13, the retaining spring 14, the sliding block 15, and the spring 16 in this embodiment are the same as those in Embodiment 2. The difference is that the slide groove 115 is located outside the housing 11, preferably, the slide groove 115 is in the shape of a square hole, and the main body of the sliding block 15 is provided with a locking end 152 and an arc-shaped end 153, which are not connected, that is, there is a gap in the middle.

[0083] Movement principle: Fig.13This is the initial state of the angle locking mechanism 1. The profile of the cam 132 itself is a symmetrical structure. The cam 132, the sliding block 15, the driving wheel 12 and the limiting feature 123 are symmetrical relative to the line connecting the two axes O1 and O2, which is the same as the first embodiment. The difference is that at this time, the center position of the cam 132 near the repose angle contacts the arc end 153 of the sliding block 15, the sliding block 15 is at the closest radial movement distance, and the limiting feature 123 is located on the center line of the far repose angle of the cam 132. When the cam 132 generates a push stroke, the sliding block 15 moves radially outward, the spring 16 is compressed, and the sliding block 15 is reset by the rebound force of the compression spring when the cam 132 generates a return stroke. Due to the special profile of the cam and the transmission ratio of the gear, the limiting feature 123 contacts and locks with the locking end 152 of the sliding block at a specific angle.

[0084] Locking status: Fig.14 As shown, this embodiment is in a locking position in a rotation direction. According to the direction shown in the figure, the rotation direction of the driving wheel 12 is counterclockwise, and the arc end 153 contacts the near rest position of the cam 132, and there is no push stroke. At this time, one side of the limiting feature 123 is in contact with the locking end 152, and the overlapping length is the largest, forming a locking position A3. The locking angular stroke of this embodiment also satisfies θ′=±(n*360°+180°-T3 / 2).

[0085] Example 4

[0086] This embodiment is a variation of the third embodiment and also utilizes the second locking principle.

[0087] like Figure 15-16 As shown, the difference is that there is no spring 16 in this embodiment. In particular, the arc-shaped end 153 of the sliding block 15 is a cylindrical structure, the profile of the cam 132 is a ring groove track, and the cam 132 and the arc-shaped end 153 form a cam pair A2. During the push stroke, the inner profile of the cam 132 applies force, and during the return stroke, the outer profile of the cam 132 applies force. The locking state of this embodiment is consistent with that of embodiment 3.

[0088] Example 5

[0089] This embodiment is an integrated angle locking mechanism, which utilizes the second locking principle and is provided with two limit features.

[0090] like Figure 17-18As shown, the angle locking mechanism 1 includes a housing 11, a driving wheel 12, an internal gear 122, a driven wheel 13, a retaining spring 14, and an end cover 5. A bearing 23 is installed below the housing 11. The gear shaft 22 passes through the bearing 23 and rotates around the rotating axis O1. The driving wheel 12 is installed and fixed above the gear shaft 22. The internal gear 122 is fixed on the driving wheel 12. A retaining spring 14 is provided above the driving wheel 12 and is installed on the gear shaft 22 to limit the axial position of the driving wheel 12. The driving wheel 12 has the same axis O1 as the internal gear 122 and the gear shaft 22, and has the same rotational angular velocity. Two limiting features 123 are provided on the driving wheel 12. A sink 114 and a slide 115 are provided at the bottom of one side of the housing 11. The sliding block 15 is provided with a hanging platform 151, a locking end 152, an arc end 153, and a slide 154. The hanging platform 151 is located inside the sink 114, and the slide 153 is located at the bottom of the slide 115 and slides to perform radial movement. When the driving wheel rotates clockwise or counterclockwise, one side of the two limiting features is used to contact the two side surfaces of the locking end 152 of the sliding block 15 to achieve locking. When the locking end 152 of the sliding block 15 contacts the limiting feature 123 of the driving wheel 12 and is subjected to force, it is locked, and the hanging platform 151 fits with the sink 114 to withstand the reaction force. Preferably, the arc end 153 is cylindrical. In addition, the lower part of the driving wheel 12 fits with the upper part of the slide plate 153 to achieve axial limitation of the sliding block 15. A countersunk hole 112 is also provided above the housing 11, and the driven wheel 13 is installed on the countersunk hole 112. A pinion 131 and a cam 132 are provided on the driven wheel 13. The cam 132 is in the shape of a cam profile annular groove. The pinion 131 is coaxial with the cam 132 and the outer ring of the driven wheel 13, and rotates together around the axis of the countersunk hole 112, that is, the rotating axis O2, and has the same angular velocity. The pinion 131 cooperates with the internal gear 122 on one side to form a gear pair A1, which is an internal meshing gear, and the center distance is O1O2. The cam 132 cooperates with the arc-shaped end 153 of the sliding block 15 on the other side to form a cam pair A2. In addition, an end cover 5 is provided above the driven wheel 13, and the end cover 5 is fixed in the housing 11 to axially limit the driven wheel 13.

[0091] Movement principle: Fig.18 This is the initial state of the angle locking mechanism 1. The groove profile of the cam 132 is a symmetrical structure. The cam 132, the sliding block 15, the driving wheel 12 and the limiting feature 123 are symmetrical structures relative to the line connecting the two axes O1O2. This is consistent with the purpose of the previous embodiment. This arrangement can simply achieve the same locking angle of the mechanism in the clockwise and counterclockwise directions. In addition, the phase angle satisfies that when the middle position of the cam 132 near the rest point contacts the arc-shaped end 153 of the sliding block 15, the sliding block 15 is at the closest radial movement distance, combined with Figure 4, the initial phase angle between the locking contact surface of the limiting feature 123 and the locking end of the sliding block 15 is θ1. When the driving wheel 12 rotates, the internal gear 122 rotates synchronously, driving the pinion 131 to rotate, the cam 132 rotates synchronously with the pinion 131, and the sliding block 15 performs radial reciprocating motion through the cam pair A2. Due to the special profile of the cam and the transmission ratio of the gear, the limiting feature 123 contacts and locks with the locking end 152 of the sliding block at a specific angle.

[0092] Locking status: Fig.19 As shown, this embodiment is in a locking position in a rotation direction. According to the direction shown in the figure, the rotation direction of the driving wheel 12 is counterclockwise, and the arc end 153 contacts the near-rest position of the cam 132 without a push stroke. At this time, one side of the limiting feature 123 is in contact with the locking end 152, and the overlapping length is the largest, forming a locking position A3. The locking angle stroke of this embodiment satisfies θ′=±(n*360°+θ1-T3 / 2).

[0093] Example 6

[0094] like Fig. 20 As shown, this embodiment provides a hand feeling simulation device, which applies and installs the angle locking mechanism described in Example 2.

[0095] The angle locking mechanism 1 is installed at the bottom of the reduction box 2. After a number of fasteners 3 pass through the fixing holes 111, the housing 11 is connected to the housing 21. After the bottom surface of the housing 21 is fitted with the upper end surface of the housing 11, the axial freedom of the driving wheel 12 is limited, so that the driving wheel 12 can rotate freely without falling out. The reduction box 2 is provided with a gear shaft 22 and a bearing 23. The gear shaft 22 rotates axially around the bearing 23. The bottom end of the gear shaft 22 penetrates into the introduction hole 121 of the driving wheel 12 to form a driving position A4, thereby driving the driving wheel 12 to rotate. The driving wheel 12, the countersunk hole 112 of the housing 1, the gear shaft 22 and the bearing 23 are coaxial.

[0096] Working principle: The hand feel simulation device includes a power unit 4, which is connected to the reduction gear box 2. The power unit 4 generates the required torque under the instruction of the internal controller and acts on the gear shaft 22. After the upper end of the gear shaft 22 is connected to the steering column, hand feel feedback is provided. The lower end of the gear shaft 22 is connected to the driving wheel 12 in the external angle locking mechanism 1, which provides a steering wheel angle locking function.

[0097] The present invention has been described in detail above through specific implementation modes and embodiments, but these do not constitute limitations of the present invention. Without departing from the principles of the present invention, those skilled in the art may also make many variations and improvements, which should also be regarded as the protection scope of the present invention.

Claims

1. An angle locking mechanism of a steering system, characterized in that: It includes a housing, a driving wheel, a driven wheel, a sliding block and a limiting feature; the driven wheel is provided with a pinion and a cam, the driving wheel is provided with an internal gear, and the internal gear and the pinion form a gear pair; The driving wheel is driven by an external driving shaft to rotate around the first rotating axis; the driven wheel is driven by the driving wheel to rotate around the second rotating axis; the cam is driven by a pinion to rotate around the second rotating axis, and the cam and the driven wheel have the same angular velocity when they rotate; the limiting feature is driven by the driving wheel to rotate around the first rotating axis, and the limiting feature and the driving wheel have the same angular velocity when they rotate; The sliding block has a locking end and an arcuate end, and the arcuate end contacts the cam; when the arcuate end contacts the far rest position or the near rest position of the cam, the limiting feature fits with the locking end to form a locking position.

2. The angle locking mechanism of the steering system according to claim 1, characterized in that: In the locking position, the locking angle of the limiting feature satisfies θ′=±(n*360°+θ1-T3 / 2), where θ′ is the locking angle, n is the number of rotations of the driving wheel, θ1 is the initial phase angle of the limiting feature, and T3 is the occupied angle of the limiting feature.

3. The angle locking mechanism of the steering system according to claim 2, characterized in that: The profile of the cam is a symmetrical structure; the cam, the sliding block, the driving wheel and the limiting feature are symmetrical relative to the connecting line structure of the first rotating shaft and the second rotating shaft.

4. The angle locking mechanism of the steering system according to claim 3, characterized in that: The upper end of the shell is provided with a countersunk hole, and the bottom is provided with a positioning column and a slide groove; The driving wheel is installed on the countersunk hole, and the driving wheel is provided with an introduction hole. The introduction hole, the outer circle of the driving wheel and the inner circle of the countersunk hole are coaxial, and the axis is the first rotating axis; after the external driving shaft is connected to the introduction hole, it drives the driving wheel to rotate in the countersunk hole, and an internal gear is provided at the bottom of the driving wheel, and a limiting feature is provided below the internal gear; The driven wheel is provided with a hole in the middle, through which the positioning column is passed and then installed on the bottom surface of the housing; a pinion is provided above the driven wheel and a cam is provided below the driven wheel, the pinion and the cam are coaxial, and the axis is the second rotating shaft; A retaining spring is fixedly arranged above the positioning column to limit the axial position of the driven wheel. The sliding block is installed at the bottom of the shell body and is located on the side of the driven wheel. The sliding block is also located in the sliding groove and can move radially in the sliding groove.

5. The angle locking mechanism of the steering system according to claim 4, characterized in that: The angle locking mechanism also includes a spring; the spring is installed in a sink groove at the bottom of the shell, and a hanging platform is provided at the bottom of the sliding block. When the sliding block moves radially outward, the hanging platform compresses the spring.

6. The angle locking mechanism of the steering system according to claim 5, characterized in that: The locking end and the arc end of the sliding block are connected; when the middle position of the far repose angle of the cam contacts the arc end of the sliding block, the sliding block is at the farthest radial movement distance, and the limiting feature is located on the center line of the near repose angle of the cam.

7. The angle locking mechanism of the steering system according to claim 4, characterized in that: The arc-shaped end of the sliding block is a cylindrical structure, the profile of the cam is a ring groove track, the cam and the arc-shaped end form a cam pair, the inner profile of the cam applies force during the push stroke, and the outer profile of the cam applies force during the return stroke.

8. The angle locking mechanism of the steering system according to claim 5 or 7, characterized in that: The slide groove is located outside the shell; the locking end and the arc end of the sliding block are not connected; when the middle position of the cam near the repose angle contacts the arc end of the sliding block, the sliding block is at the shortest radial movement distance, and the limiting feature is located on the center line of the cam far repose angle.

9. The angle locking mechanism of the steering system according to claim 3, characterized in that: The angle locking mechanism includes a bearing and a gear shaft; A bearing is installed below the housing, and the gear shaft passes through the bearing and rotates around the first rotating shaft; the driving wheel is installed and fixed above the gear shaft, and the internal gear is fixed on the driving wheel; a retaining spring is provided above the driving wheel and installed on the gear shaft; the driving wheel, the internal gear and the gear shaft have the same axis and the same rotation angular velocity, and the axis is the first rotating shaft; The bottom of one side of the shell is provided with a sink and a slide, and the sliding block is provided with a hanging platform and a slide plate, the hanging platform is located inside the sink, and the slide plate is located on the bottom of the slide plate and slides to make radial movement; the lower part of the driving wheel is in contact with the upper part of the slide plate; and two limiting features are provided on the driving wheel; A countersunk hole is also provided above the shell, and the driven wheel is installed on the countersunk hole. A pinion and a cam are provided on the driven wheel. The cam is in the shape of a cam profile annular groove. The pinion is coaxial with the cam and the outer ring of the driven wheel, and they rotate together around the axis of the countersunk hole with the same angular velocity. The axis is the second rotating shaft.

10. The angle locking mechanism of the steering system according to claim 9, characterized in that: The arc-shaped end of the sliding block is in the shape of a cylinder.

11. The angle locking mechanism of the steering system according to claim 9, characterized in that: An end cover is also provided above the driven wheel, and the end cover is fixed in the shell to limit the axial position of the driven wheel.

12. The angle locking mechanism of the steering system according to claim 9, characterized in that: When the middle position of the cam near the rest point contacts the arcuate end of the sliding block, the sliding block is at the shortest radial movement distance.

13. The angle locking mechanism of the steering system according to claim 2, characterized in that: The design method of the parameters of the driving wheel, the driven wheel, the cam, the sliding block and the limiting feature in the angle locking mechanism is: Step S1, determining the maximum outer diameter of the driving wheel and the pitch circle diameter of the internal gear according to the envelope size and the maximum load torque constraint; Step S2, setting the gear ratio of the gear pair; Step S3, setting the maximum push stroke and movement angle of the cam; Step S4, checking whether the maximum contact pressure angle of the cam pair is self-locking, if not self-locking, proceeding to step S5, if self-locking, returning to step S3, resetting the maximum push stroke and movement angle of the cam; Step S5, check the strength of the limit feature, if it meets the requirements, proceed to step S6, if it does not meet the requirements, return to step S3, and reset the maximum push stroke and movement angle of the cam; Step S6, checking the locking angle of the angle locking mechanism when locked according to the gear ratio and the movement cycle of the sliding block, if the locking angle meets the preset angle range, the process ends, otherwise, step S2, resetting the gear ratio of the gear pair.

14. A steering system hand feeling simulation device, characterized in that: It comprises a power unit, a reduction gear box and an angle locking mechanism; the angle locking mechanism is installed at the bottom of the reduction gear box, the power unit generates the required torque under the specification of an internal controller, and acts on the gear shaft, the upper end of the gear shaft is connected to the steering column, and the lower end of the gear shaft is connected to the driving wheel of the angle locking mechanism; the angle locking mechanism is the angle locking mechanism described in any one of claims 4 to 8.

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