JP2015179494A - Self-traveling vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a self-traveling vehicle capable of surely stopping, when there is an obstacle in a travel direction.SOLUTION: A self-traveling vehicle 100 according to one embodiment of the invention comprises: a drive wheel 12; a drive force generation part 20 for generating drive force; a step detection part 30 for displacing when it is located on a step; and a displacement conversion part 40 for utilizing displacement of the step detection part 30 for mechanically blocking transmission of the drive force to the drive wheel 12 from the drive force generation part 20. The displacement conversion part 40 does not block transmission of the drive force to the drive wheel 12 from the drive force generation part 20, until displacement of the step detection part 30 reaches a predetermined degree.

Description

  The present invention relates to a self-propelled vehicle.

  In self-propelled vehicles that have been developed in recent years, the fall prevention function and the collision safety function are indispensable technologies for safety. The fall prevention function is typically a function of executing stop control by detecting a descending step using a non-contact sensor or a limit switch attached to the end of the machine body. The collision safety function is typically a function of executing stop control by detecting an obstacle using a non-contact sensor attached to the end of the airframe. As an application example of the collision safety function, an obstacle detection device (see Patent Document 1) in an article storage device of an article storage facility using an optical sensor, and an autonomous transport using a camera mounted on an autonomous transport vehicle. 2. Description of the Related Art An autonomous transport system (see Patent Document 2) that detects contact between a carriage towed by a vehicle and an obstacle is known.

  However, since such an electrical fall prevention function and collision safety function are functions that use electrical signals and control processing, they may not operate normally when a malfunction occurs in the electrical system or software.

  On the other hand, the self-propelled cleaner provided with the mechanical fall prevention function is known (refer patent document 3). This self-propelled cleaner includes a driving wheel and a steering wheel for traveling on a vehicle body portion provided with a suction tool that sucks dust on the floor surface. Also, the side brush that descends when it enters the down step on the floor, and the vehicle body so that the drive wheels are lifted using the inertial force of the vehicle body part as the side brush descends and comes into contact with the floor. And a cam plate for lifting the part. Then, the traveling is stopped by lifting the vehicle body with the cam plate.

Japanese Patent No. 4937603 JP 2013-191138 A JP-A-8-80277

  However, the self-propelled cleaner of Patent Document 3 tries to stop the traveling while allowing mechanical transmission of the driving force from the motor to the driving wheel. Therefore, when the inertial force of the vehicle body is smaller than the force required to lift the drive wheel from the floor surface, there is a possibility that the vehicle continues to run while sliding the cam plate in contact with the floor surface forward in the traveling direction.

  In view of the above points, it is desirable to provide a self-propelled vehicle that can stop more reliably when there is a failure in the traveling direction.

  A self-propelled vehicle according to an embodiment of the present invention includes a drive wheel, a drive force generation unit that generates a drive force for driving the drive wheel, and a displacement detection unit that is displaced when an obstacle in the traveling direction is reached. And a displacement converter for interrupting transmission of the driving force from the driving force generator to the driving wheel using the displacement of the displacement detector.

  The above-described means provides a self-propelled vehicle that can be stopped more reliably when there is a failure in the traveling direction.

It is a figure which shows the structural example of the self-propelled vehicle by one Embodiment of this invention. It is a perspective view of a motor support part. It is a perspective view of a level | step difference detection part. It is a perspective view of a displacement conversion part. It is a figure which shows the motion of the driving force generation | occurrence | production part, level | step difference detection part, and displacement conversion part when the self-propelled vehicle of FIG. It is a figure which shows another structural example of the self-propelled vehicle by one Embodiment of this invention. It is a figure which shows the motion of a driving force generation | occurrence | production part, an obstruction detection part, and a displacement conversion part when the self-propelled vehicle of FIG. 6 contacts an obstruction. It is a figure which shows the structural example of the brake mechanism mounted in a self-propelled vehicle.

  Initially, the whole structure of the self-propelled vehicle 100 by one Embodiment of this invention is demonstrated. FIG. 1 is a diagram illustrating a configuration example of a self-propelled vehicle 100. 1 is a perspective view of the self-propelled vehicle 100, and the right diagram of FIG. 1 is a top view of the self-propelled vehicle 100.

  The self-propelled vehicle 100 is a vehicle that self-propells with the + X direction as a traveling direction, and mainly includes a main body 10, a driving force generator 20, a step detector 30, and a displacement converter 40. Note that FIG. 1 illustrates only the front left part of the traveling direction of the self-propelled vehicle 100 for the sake of clarity, and shows the right and rear parts of the traveling direction and the upper structure mounted on the main body 10. Illustration is omitted. In addition, a battery, a control device, and the like are mounted on the upper structure (not shown).

  The main body 10 mainly includes a base 11, drive wheels 12, and drive wheel side gears 14. In the present embodiment, the base 11 is a plate-like member, and rotatably supports the rotating shaft 12A of the drive wheel 12. The drive wheel side gear 14 is a power transmission member that rotates integrally with the rotary shaft 12A, and is coupled to the rotary shaft 12A by a key coupling mechanism in this embodiment. The drive wheel side gear 14 may be coupled to the rotary shaft 12A by bolt fastening, spline fastening, shrink fitting, or the like. Further, FIG. 1 illustrates only the configuration around the driving wheel on the left side in the traveling direction, but in reality, a similar configuration exists on the right side in the traveling direction.

  The driving force generation unit 20 is a functional element that generates a driving force, and mainly includes a motor 21, a motor support unit 22, and a motor side gear 23.

  The motor 21 is an electric motor that drives the drive wheels 12 and is driven by electric power of a battery mounted on the upper structure under the control of a control device mounted on the upper structure. In the present embodiment, the self-propelled vehicle 100 is steered using the difference between the rotational speeds of the left and right drive wheels. Therefore, the motor 21 drives only the driving wheel 12 on the left side in the traveling direction. However, the present invention is not limited to this configuration. For example, the self-propelled vehicle 100 may be steered using steered wheels (not shown). In this case, the motor 21 may drive a pair of left and right drive wheels. The motor 21 may drive three or more drive wheels.

  The motor support portion 22 is a member that supports the motor 21. FIG. 2 is a perspective view of the motor support 22. In the present embodiment, the motor support portion 22 includes a base portion 22A extending in the Y-axis direction, and an upper wall portion 22B extending in the + Z direction and extending in the X-axis direction from the + Z side surface of the base portion 22A. Further, the + X side surface of the base portion 22A and the + X side surface of the upper wall portion 22B form the same plane, and the length of the upper wall portion 22B in the X axis direction is larger than the length of the base portion 22A in the X axis direction. Therefore, the upper wall portion 22B protrudes beyond the −X side surface of the base portion 22A, and forms a space 22C on the −Z side.

  The non-rotating portion of the motor 21 is attached to substantially the center of the upper wall portion 22B so that the rotation shaft 21A extends in the Y-axis direction and penetrates the upper wall portion 22B in the Y-axis direction.

  The motor side gear 23 is a power transmission member that rotates integrally with the rotating shaft 21A of the motor 21, and is coupled to the rotating shaft 21A by a key coupling mechanism in this embodiment. The motor side gear 23 is configured to be able to transmit the driving force of the motor 21 to the driving wheel 12 by engaging with the driving wheel side gear 14.

  The level difference detection unit 30, which is an example of a displacement detection unit, is a functional element that detects a down level difference ahead of the traveling direction of the self-propelled vehicle 100. FIG. 3 is a perspective view of the level difference detection unit 30. In the present embodiment, the level difference detection unit 30 mainly includes a driven wheel 31, a displacement transmission member 32, a turning shaft support member 33, a biasing element 34, and a biasing element support member 35. And the level | step difference detection part 30 is arrange | positioned ahead of the advancing direction with respect to the driving wheel 12 so that the driving wheel 12 can detect the down level | step difference before reaching | attaining a down level | step difference. In the present embodiment, detection of a downward step means that the displacement of the step detection unit 30 is greater than or equal to a predetermined size. Further, the displacement of the level difference detection unit 30 means the displacement of the level difference detection unit 30 with respect to the reference posture. The reference attitude of the level difference detection unit 30 is an attitude when the level difference detection unit 30 is not positioned at a downward level difference. For example, as shown in FIG. 1, the driven wheel is the same road surface as the horizontal road surface on which the drive wheels 12 are located. This is the posture when 31 is located.

  The driven wheel 31 is a wheel that rotates in response to the propulsive force generated by the drive wheel 12, and is rotatably supported by the displacement transmission member 32 via the rotation shaft 31A. Then, the driven wheel 31 is displaced in the −Z direction by a force in the −Z direction (vertically below) generated by the biasing element 34 when positioned at the down step. This is because the road surface supporting the driven wheel 31 disappears. Note that the level difference detection unit 30 may use the weight of the driven wheel 31 in addition to or instead of the force in the −Z direction generated by the biasing element 34.

  In the present embodiment, the self-propelled vehicle 100 includes a driven wheel (not shown) that is rotatably supported by the main body unit 10 in addition to the driven wheel 31 that is rotatably supported by the step detection unit 30. Therefore, the level difference detection unit 30 may have a low friction member that contacts the road surface instead of the driven wheel 31. The low friction member has, for example, a portion that contacts the road surface with low friction (for example, a rolling element such as a free caster, or a semi-spherical or semi-cylindrical non-rolling element) at the tip. It is the attached rod-shaped member. Since the self-propelled vehicle 100 includes the driven wheel 31, a driven wheel (not shown) that is rotatably supported by the main body 10 may be omitted.

  The displacement transmission member 32 is a member that mechanically transmits the detection of the downward step to the displacement conversion unit 40. In the present embodiment, the displacement transmission member 32 is a member that transmits the displacement of the driven wheel 31 to the displacement conversion unit 40, and includes a rod-shaped portion 32A, a driven wheel support portion 32B, a turning connection portion 32C, and a displacement absorbing portion 32D.

The rod-shaped portion 32A is a rod-shaped member extending in the X-axis direction, and the turning connection portion 32C is attached near the end on the + X side at the center.

  The driven wheel support portion 32B is a portion that protrudes perpendicularly in the −Z direction from the + X side end portion of the rod-shaped portion 32A, and rotatably supports the rotating shaft 31A of the driven wheel 31.

  The swivel connection portion 32C is a part that forms a swivel axis of the displacement transmission member 32, and has a swivel axis that extends in the Y-axis direction. Further, the turning connecting portion 32C is disposed near the end on the + X side in the center of the rod-like portion 32A, and constitutes a fulcrum of the insulator. Then, the turning connecting portion 32C converts the displacement in the −Z direction at the + X side end of the rod-shaped portion 32A into the displacement in the + Z direction at the −X side end of the rod-shaped portion 32A and amplifies it. Note that the swivel connecting portion 32C may be disposed near the end on the -X side in the center of the rod-like portion 32A. In this case, the swivel connecting portion 32C can convert and reduce the displacement in the −Z direction of the + X side end of the rod-shaped portion 32A into the displacement in the + Z direction of the −X side end of the rod-shaped portion 32A.

  The displacement absorbing unit 32D absorbs the displacement when the displacement of the level difference detecting unit 30 is less than a predetermined size, and does not transmit the displacement to the displacement converting unit 40 until the displacement reaches a predetermined size. It is a functional part. Specifically, the displacement absorbing unit 32 </ b> D is displaced according to the displacement of the level difference detecting unit 30. And the displacement absorption part 32D has the extension part extended along the direction of the displacement of the displacement absorption part 32D.

  In the present embodiment, the displacement absorbing unit 32D has an extension that extends along a locus drawn when the step detector 30 is displaced. Specifically, the displacement absorbing portion 32D has an arc shape in the −Z direction from the −X side end of the rod-shaped portion 32A along the locus drawn when the −X-side end of the rod-shaped portion 32A is displaced. Has an extension that extends. This arc shape prevents the displacement absorbing portion 32D from colliding with other members when displaced in the + Z direction.

  The displacement absorbing portion 32D has a groove portion 32Da that receives the slide pin 42 of the displacement converting portion 40. The slide pin 42 (see FIG. 1) is a member for operating the displacement conversion unit 40, and details thereof will be described later. In general, as long as the displacement in the + Z direction of the displacement absorbing portion 32D is less than a predetermined size and the slide pin 42 is in the groove portion 32Da, the operation of the displacement converting portion 40 is not started. On the other hand, when the displacement in the + Z direction of the displacement absorbing portion 32D exceeds a predetermined size, the slide pin 42 comes out of the groove 32Da and the operation of the displacement converting portion 40 is started.

  With this configuration, the displacement absorbing portion 32D can prevent a shallow concave portion on the road surface that should not be detected as a down step from being detected as a down step. As a result, the displacement absorbing portion 32D can prevent the movement of the self-propelled vehicle 100 from stopping due to the presence of such a shallow recess. Further, the designer can determine the size (depth) in the Z-axis direction of the concave portion to be detected as the descending step by adjusting the length (arc length) of the extension portion of the displacement absorbing portion 32D. . Specifically, as the arc length is shorter, a shallower recess is detected as a descending step. That is, as the arc length is longer, the shallow concave portion is not detected as a downward step.

  The extension portion may extend in a direction deviating from the locus drawn when the end portion on the −X side of the rod-shaped portion 32A is displaced (for example, the −Z direction). If the displacement absorbing portion 32D can be engaged with the slide pin 42, and the displacement absorbing portion 32D can avoid collision with other members when displaced in the + Z direction, the extension direction of the extension portion can be traced. This is because it is not necessary to limit the direction along the direction.

  In addition, the designer adjusts the size (diameter) in the X-axis direction and the size (horizontal width) in the Y-axis direction of the driven wheel 31 to thereby adjust the size (in the X-axis direction) of the recess to be detected as the descending step (Vertical width) and Y-axis direction size (horizontal width) are determined. However, for example, when the driven wheel 31 is not used, the designer may determine the size (depth, vertical width, horizontal width) of the concave portion to be detected as the descending step by using another structure. . For example, the designer may use a low friction member that is in contact with the road surface instead of the driven wheel 31 as a structure for determining the size (depth, vertical width, horizontal width) of the recess to be detected as the descending step. Good. In this case, the designer can determine the vertical width and the horizontal width of the concave portion to be detected as the descending step by the vertical width and the horizontal width of the portion in contact with the road surface in the low friction member.

  The pivot shaft support member 33 is a member that supports the pivot coupling portion 32 </ b> C of the displacement transmission member 32, and is rigidly coupled to the main body portion 10.

  The urging element 34 is a member that reliably displaces the level difference detection unit 30 when the level difference detection unit 30 is positioned at the descending level difference. In the present embodiment, the biasing element 34 is a compression spring, and biases the + X side end of the rod-shaped portion 32A in the −Z direction. And when the level | step difference detection part 30 is located in a downward level | step difference, the urging | biasing element 34 accelerates | stimulates the displacement of the level | step difference detection part 30 by pushing down the edge part in -Z direction.

  The urging element 34 may be composed of a pair of permanent magnets so that the repulsive force by the two permanent magnets can be used. In this case, one permanent magnet is attached to the biasing element support member 35, and the other permanent magnet is attached to the + X side end of the rod-like portion 32A. Further, the urging element 34 may be omitted when the weight of the driven wheel 31 is large. This is because the natural fall of the driven wheel 31 can be used instead of pushing down the driven wheel 31 by the biasing element 34.

  The biasing element support member 35 is a member that supports the + Z side end of the biasing element 34 and is rigidly coupled to the main body 10.

  The displacement conversion unit 40 is a functional element that displaces another member using the displacement of a predetermined member. In the present embodiment, the displacement converter 40 mechanically interrupts the transmission of the driving force from the driving force generator 20 to the driving wheel 12 using the displacement of the step detector 30. Specifically, the displacement conversion unit 40 converts the displacement of the level difference detection unit 30 into a relative displacement between the driving force generation unit 20 and the driving wheel 12. The displacement conversion unit 40 moves the driving force generation unit 20 away from the driving wheel 12, that is, moves the motor support unit 22 away from the base 11, thereby reducing the driving force from the driving force generation unit 20 to the driving wheel 12. Block transmission.

  Further, the displacement conversion unit 40 is configured not to move the motor support unit 22 away from the base 11 if the displacement of the step detection unit 30 is less than a predetermined size. This configuration is mainly brought about by the displacement absorbing portion 32D of the displacement transmitting member 32 in the step detecting portion 30 and the slide pin 42 of the displacement converting portion 40. As a result, the meshing between the driving wheel side gear 14 and the motor side gear 23 is maintained, and transmission of the driving force from the driving force generator 20 to the driving wheel 12 is continued. At this time, the motor support 22 is in a standard contact state. The standard contact state is a state in which the bottom surface (the surface on the −Z side) of the motor support portion 22 is in contact with the surface of the base 11 (the surface on the + Z side), for example, the state shown in FIG.

  On the other hand, when the displacement of the level difference detection unit 30 exceeds a predetermined magnitude, the displacement conversion unit 40 displaces the motor support unit 22 away from the base 11. As a result, the meshing between the driving wheel side gear 14 and the motor side gear 23 is released, and transmission of the driving force from the driving force generating unit 20 to the driving wheel 12 is interrupted. At this time, the motor support portion 22 is in a lifted state in which the −Z side surface (bottom surface) does not contact the + Z side surface (front surface) of the base 11.

  FIG. 4 is a perspective view of the displacement converter 40. The displacement converter 40 mainly includes a slide pin guide 41, a slide pin 42, a tension spring 43, a tension spring support member 44, a compression spring 45, a compression spring support member 46, and a motor support section guide 47.

  The slide pin guide 41 is a member that guides the slide pin 42 that slides in the X-axis direction. In the present embodiment, the slide pin guide 41 is configured by forming a through guide hole 41 </ b> H in a block-like member fixed to the base 11. The shape of the slide pin guide 41 is formed so as to match the shape of the space 22 </ b> C (see FIG. 2) formed by the motor support portion 22.

  The position of the penetration guide hole 41H is formed so as to coincide with the position of the penetration guide hole 22H (see FIG. 2) formed in the base portion 22A of the motor support portion 22 when the motor support portion 22 is in a standard contact state. . Further, the diameter of the penetration guide hole 41H is preferably formed to be equal to the diameter of the penetration guide hole 22H. The motor support portion 22 is maintained in the standard contact state by the slide pin 42 remaining in both the through guide hole 22H and the through guide hole 41H.

  The slide pin 42 has a head part 42A, a neck part 42B, and a holding part 42C. In this embodiment, each part of the slide pin 42 has a cylindrical shape. However, each part of the slide pin 42 may have other shapes such as a prismatic shape and an elliptical prism shape.

  The head part 42A is formed at the end on the + X side, and the neck part 42B is formed between the head part 42A and the holding part 42C. The recess formed by the head portion 42A and the neck portion 42B functions to detachably engage (lock) the displacement absorbing portion 32D of the displacement transmitting member 32 and the slide pin 42.

  Specifically, the head part 42A has a diameter larger than the width of the groove part 32Da of the displacement absorbing part 32D. The neck portion 42B has a diameter smaller than the width of the groove portion 32Da and a length larger than the depth of the groove portion 32Da. With this configuration, the slide pin 42 is displaced when the neck portion 42B is received in the groove portion 32Da of the displacement absorbing portion 32D, and the −X side surface of the head portion 42A comes into contact with the + X side surface of the displacement absorbing portion 32D. The absorber 32D is detachably locked.

  The holding portion 42 </ b> C is formed on the −X side of the neck portion 42 </ b> B, and is used to restrain the motor support portion 22 to the slide pin guide 41. In the present embodiment, the holding portion 42C has a diameter corresponding to the diameters of the through guide hole 22H and the through guide hole 41H and a length larger than the total length of the through guide hole 22H and the through guide hole 41H. The holding portion 42C has a diameter corresponding to the diameters of the through guide hole 22H and the through guide hole 41H so that the holding portion 42C can slide smoothly without rattling in the through guide hole 22H and the through guide hole 41H. It means having a determined diameter. The slide pin 42 engages with the motor support portion 22 when the holding portion 42C is positioned so as to straddle both the penetration guide hole 22H and the penetration guide hole 41H, and the motor support portion 22 is restrained by the slide pin guide 41. To the standard contact state.

  The head portion 42A has a diameter corresponding to the diameters of the through guide hole 22H and the through guide hole 41H. The head portion 42A has a diameter corresponding to the diameters of the through guide hole 22H and the through guide hole 41H, so that the head portion 42A can be smoothly slid without shaking in the through guide hole 22H and the through guide hole 41H. Means having a different diameter. The head portion 42A desirably has a diameter smaller than the diameters of the through guide hole 41H and the through guide hole 22H. This is because the slide pin 42 can smoothly move in the through guide hole 22H and the through guide hole 41H.

  The tension spring 43 generates a force that pulls the slide pin 42 in the −X direction. In the present embodiment, the + X side end of the tension spring 43 is fixed to the slide pin 42, and the −X side end is fixed to the tension spring support member 44. The tension spring 43 is in an extended state when the displacement absorbing portion 32D of the displacement transmitting member 32 and the slide pin 42 are engaged, and contracts when the engagement is released to cause the slide pin 42 to move in the −X direction. Move to.

  The tension spring support member 44 is a member that fixes the end portion on the −X side of the tension spring 43. In this embodiment, the tension spring support member 44 is fixed to the surface (surface) on the + Z side of the base 11.

  The compression spring 45 generates a force that displaces the motor support portion 22 in the + Z direction. In the present embodiment, the compression spring 45 is fixed to the compression spring support member 46 at the −Z side end. The compression spring 45 is in a compressed state when the motor support portion 22 is in a standard contact state, that is, when the displacement absorbing portion 32D and the slide pin 42 are engaged, and biases the motor support portion 22 in the + Z direction. ing. When the engagement between the displacement absorbing portion 32D and the slide pin 42 is released, the displacement is extended and the motor support portion 22 is lifted in the + Z direction. Specifically, when the engagement between the displacement absorbing portion 32D and the slide pin 42 is released, the slide pin 42 is pulled in the −X direction by the tension spring 43 and comes out of the through guide hole 22H. When the slide pin 42 comes out of the through guide hole 22H, the restraint between the motor support portion 22 and the slide pin guide 41 is released, and the motor support portion 22 is lifted in the + Z direction by the compression spring 45.

  The compression spring support member 46 is a member that fixes the end portion of the compression spring 45 on the −Z side. In the present embodiment, the compression spring support member 46 is constituted by a stay attached to the surface (bottom surface) on the −Z side of the base 11. In this case, the compression spring 45 passes through the through hole 11H that penetrates the base 11 in the Z-axis direction.

  The motor support portion guide 47 is a member that guides the displacement of the motor support portion 22 in the Z-axis direction. In the present embodiment, the motor support guide 47 is composed of four motor bracket guides extending in the Z-axis direction. The four motor bracket guides are positioned adjacent to the motor support 22 in the standard contact state in order to prevent rotation of the motor support 22 around the three axes and translation in the X-axis and Y-axis directions. Be placed.

  FIG. 5 shows the movements of the driving force generation unit 20, the step detection unit 30, and the displacement conversion unit 40 when the self-propelled vehicle 100 reaches a descending step. FIG. 5 includes an upper diagram, a middle diagram, and a lower diagram, and shows the movement of each part in the order of the upper diagram, the middle diagram, and the lower diagram.

  As shown in the upper diagram of FIG. 5, the driven wheel 31 that has reached the descending step is displaced in the −Z direction by its own weight and a force (see arrow AR <b> 1) by the biasing element 34. As a result, the displacement transmitting member 32 turns counterclockwise about the turning connection part 32C as shown by the arrow AR2, and displaces the displacement absorbing part 32D in the + Z direction. When the magnitude of displacement in the + Z direction of the displacement absorbing portion 32D exceeds a predetermined magnitude, the engagement between the displacement absorbing portion 32D and the slide pin 42 is released. Specifically, when the displacement absorbing portion 32D is displaced in the + Z direction, the neck portion 42B of the slide pin 42 apparently slides in the groove portion 32Da of the displacement absorbing portion 32D toward the end portion of the groove portion 32Da. And when the magnitude | size of the displacement to the + Z direction of the displacement absorption part 32D exceeds predetermined magnitude | size, the neck part 42B will appear outside the groove part 32Da and will be released from the displacement absorption part 32D.

  When the engagement between the displacement absorbing portion 32D and the slide pin 42 is released, the slide pin 42 is pulled in the −X direction by the tension spring 43 as shown in FIG. Slide in the -X direction through the hole 22H. Specifically, the slide pin 42 slides so that the head portion 42 </ b> A is positioned on the −X side with respect to the motor support portion 22. As a result, the engagement between the slide pin 42 and the motor support portion 22 is released, and the restraint between the motor support portion 22 and the slide pin guide 41 is released.

  When the restraint between the motor support portion 22 and the slide pin guide 41 is released, the motor support portion 22 is lifted in the + Z direction by the compression spring 45 as shown in the lower diagram of FIG. The motor side gear 23 key-coupled to the rotation shaft 21A of the motor 21 is displaced in the + Z direction as indicated by an arrow AR3, and the drive wheel side gear 14 key-coupled to the rotation shaft 12A of the drive wheel 12 is provided. The engagement with is released.

  In this way, the displacement converting unit 40 blocks the transmission of the driving force from the driving force generating unit 20 to the driving wheel 12 by using the displacement of the level difference detecting unit 30. Specifically, the displacement conversion unit 40 uses the series of displacements caused by the displacement of the driven wheel 31 of the step detection unit 30 in the −Z direction without using electric power, from the motor 21 to the driving wheel 12. The transmission of the driving force is mechanically interrupted. The series of displacements includes a displacement absorbing part 32D of the level difference detecting unit 30 in the + Z direction, a slide pin 42 in the −X direction, and a motor supporting part 22 in the + Z direction.

  Further, the self-propelled vehicle 100 generates a braking force for preventing the self-propelled vehicle 100 from traveling by inertia when the transmission of the driving force from the driving force generator 20 to the drive wheels 12 is cut off. Let Specifically, the self-propelled vehicle 100 includes a braking member such as a pad or a claw configured to be displaced toward the road surface according to the displacement of the level difference detection unit 30 and to be in frictional contact with the road surface. Alternatively, the self-propelled vehicle 100 may attach a brake to the drive wheel 12. Specifically, the self-propelled vehicle 100 includes, for example, a normally closed switch that is in a cut-off state (open state) only when the step detection unit 30 detects a down step, and the normally closed switch is in a cut-off state. And a brake that operates when it becomes.

  With the above configuration, the self-propelled vehicle 100 mechanically interrupts transmission of the driving force from the driving force generation unit 20 to the driving wheels 12 when the level difference detection unit 30 detects the descending level difference. Specifically, the displacement conversion unit 40 converts the displacement of the level difference detection unit 30 into a relative displacement between the driving wheel side gear 14 and the motor side gear 23 to separate the motor side gear 23 from the driving wheel side gear 14. Thus, the transmission of the driving force from the driving force generator 20 to the driving wheel 12 is mechanically interrupted. Therefore, the self-propelled vehicle 100 can more reliably prevent the drive wheels 12 from entering the descending step and falling compared to the electrical fall prevention function.

  The step detection unit 30 absorbs the displacement when the displacement of the step detection unit 30 is less than a predetermined size, and does not transmit the displacement to the displacement conversion unit 40 until the displacement reaches a predetermined size. A displacement absorbing portion 32D is provided. Therefore, the displacement converter 40 does not block the transmission of the driving force from the driving force generator 20 to the driving wheels 12 until the displacement of the step detector 30 reaches a predetermined magnitude. As a result, the self-propelled vehicle 100 can prevent a shallow concave portion on the road surface that should not be detected as a descending step from being detected as a descending step.

  Further, the displacement absorbing unit 32D has an extending portion that extends along a locus drawn when the step detecting unit 30 is displaced. And the depth of the recessed part which should be detected as a descending level | step difference is decided by the length of the extension part. Therefore, the designer can adjust the depth of the concave portion to be detected as the descending step by adjusting the length of the displacement absorbing portion 32D.

  The self-propelled vehicle 100 includes a biasing element 34 that biases the level difference detection unit 30. And the urging | biasing element 34 accelerates | stimulates the displacement of the level | step difference detection part 30, when the level | step difference detection part 30 is located in a descending level | step difference. Therefore, the self-propelled vehicle 100 can make the displacement of the level difference detection unit 30 to be greater than or equal to a predetermined size earlier when the level difference detection unit 30 is located in a recess that should be detected as a downward level difference. As a result, the self-propelled vehicle 100 can detect the step earlier, and can more reliably prevent the drive wheel 12 from entering the descending step and falling.

  Next, another configuration example of the self-propelled vehicle 100 will be described with reference to FIG. FIG. 6 is a perspective view of the self-propelled vehicle 100. For the sake of clarity, only the left front portion of the traveling direction of the self-propelled vehicle 100 is illustrated, and the right and rear portions of the traveling direction and the main body are illustrated. Illustration of the upper structure mounted on the part 10 is omitted. A battery, a control device, and the like are mounted on an upper structure (not shown). 6 is different from the self-propelled vehicle 100 of FIG. 1 mainly in that an obstacle detection unit 30M is provided instead of the step detection unit 30.

  The self-propelled vehicle 100 in FIG. 6 is a vehicle that self-propells with the + X direction as the traveling direction, similar to the self-propelled vehicle 100 in FIG. 1. 30M and the displacement conversion part 40 are included.

  The main body 10 mainly includes a base 11, drive wheels 12, and drive wheel side gears 14. In the present embodiment, the base 11 is a plate-like member, and rotatably supports the rotating shaft 12A of the drive wheel 12. The drive wheel side gear 14 is a power transmission member that rotates integrally with the rotary shaft 12A. Further, FIG. 6 illustrates only the configuration around the driving wheel on the left side in the traveling direction, but actually, a similar configuration exists on the right side in the traveling direction.

  The driving force generation unit 20 is a functional element that generates a driving force, and mainly includes a motor 21, a motor support unit 22, and a motor side gear 23.

  The motor 21 is an electric motor that drives the drive wheels 12 and is driven by electric power of a battery mounted on the upper structure under the control of a control device mounted on the upper structure.

  The motor support portion 22 is a member that supports the motor 21. In the present embodiment, the motor support portion 22 includes a base portion 22A extending in the Y-axis direction, and an upper wall portion 22B extending in the + Z direction and extending in the X-axis direction from the + Z side surface of the base portion 22A.

  The non-rotating portion of the motor 21 is attached to substantially the center of the upper wall portion 22B so that the rotation shaft 21A extends in the Y-axis direction and penetrates the upper wall portion 22B in the Y-axis direction.

  The motor side gear 23 is a power transmission member that rotates integrally with the rotating shaft 21A of the motor 21, and is coupled to the rotating shaft 21A by a key coupling mechanism in this embodiment. The motor side gear 23 is configured to be able to transmit the driving force of the motor 21 to the driving wheel 12 by engaging with the driving wheel side gear 14. In the present embodiment, the self-propelled vehicle 100 includes a driven wheel (not shown) that is rotatably supported by the main body 10.

  The obstacle detection unit 30M, which is another example of the displacement detection unit, is a functional element that detects an obstacle in front of the traveling direction of the self-propelled vehicle 100. Obstacles include people, animals, vehicles, ascending steps, walls, color cones (registered trademark), utility poles, and the like. In the present embodiment, the obstacle detection unit 30M mainly includes a bumper 31M, a displacement transmission member 32M, a biasing element 34M, and a biasing element support member 35M. The obstacle detection unit 30M is arranged forward in the traveling direction with respect to the drive wheel 12 so that the obstacle can be detected before the main body unit 10 collides with the obstacle. In the present embodiment, the detection of an obstacle means that the displacement of the obstacle detection unit 30M is greater than or equal to a predetermined size. Further, the displacement of the obstacle detection unit 30M means the displacement of the obstacle detection unit 30M with respect to the reference posture. The reference posture of the obstacle detection unit 30M is a posture when the obstacle detection unit 30M is not in contact with the obstacle, for example, as shown in FIG.

  The bumper 31M is a member arranged so as to come into contact with the obstacle before the main body portion 10 comes into contact with the obstacle ahead of the traveling direction. In the present embodiment, the bumper 31M is configured by a flat plate parallel to the YZ plane, and is connected to the displacement transmission member 32M on the −X side surface. In the present embodiment, the bumper 31M and the displacement transmission member 32M are integrally formed. However, the bumper 31M and the displacement transmission member 32M may be formed separately.

  The displacement transmission member 32M is a member that mechanically transmits to the displacement conversion unit 40 that an obstacle has been detected. In the present embodiment, the displacement transmission member 32M is a member that transmits the displacement of the bumper 31M to the displacement conversion unit 40, and a biasing element 34M is attached to an end portion on the −X side.

  The biasing element 34M is a member that biases the bumper 31M and the displacement transmission member 32M in the + X direction. In the present embodiment, the urging element 34M is a compression spring, and is disposed between the displacement transmission member 32M and the urging element support member 35M. Then, when the bumper 31M comes into contact with the obstacle, a force that presses the bumper 31M against the obstacle is generated.

  The urging element support member 35 </ b> M is a member that supports the + Z side end of the urging element 34, and is rigidly coupled to the main body 10.

  The biasing element 34M may be composed of a pair of permanent magnets so that the repulsive force by the two permanent magnets can be used. In this case, one permanent magnet is attached to the biasing element support member 35M, and the other permanent magnet is attached to the end portion on the −X side of the displacement transmitting member 32M.

  Further, the displacement transmission member 32M includes a displacement absorbing portion 32MD. The displacement absorbing unit 32MD absorbs the displacement when the displacement of the bumper 31M in the −X direction is less than a predetermined size, and transmits the displacement to the displacement converting unit 40 until the displacement becomes a predetermined size. Do not.

  Specifically, the displacement absorbing portion 32MD has an overlapping portion that presses the base portion 22A that is about to move in the + Z direction. The overlapping portion overlaps the base portion 22A of the motor support portion 22 in the Z-axis direction when the obstacle detection portion 30M is in the reference posture.

  With this configuration, when the displacement of the bumper 31M in the −X direction is less than a predetermined size and the displacement absorbing portion 32MD overlaps the base portion 22A, the operation of the displacement converting portion 40 is not started. On the other hand, when the displacement of the bumper 31M in the −X direction exceeds a predetermined magnitude, the overlap between the displacement absorbing portion 32MD and the base portion 22A is released, and the operation of the displacement converting portion 40 is started.

  Therefore, the displacement absorbing unit 32MD can prevent an object with small inertia that should not be detected as an obstacle from being detected as an obstacle. As a result, the displacement absorbing unit 32MD can prevent the movement of the self-propelled vehicle 100 from being stopped due to the presence of such an object having low inertia. Further, the designer can determine the inertia of the object to be detected as an obstacle by adjusting the width (length in the X-axis direction) of the overlapping portion of the displacement absorbing portion 32MD. Specifically, the smaller the width of the overlapping portion, the easier it is to detect an object with low inertia as an obstacle. In other words, as the width of the overlapping portion is larger, an object with low inertia is less likely to be detected as an obstacle.

  The designer adjusts the magnitude of the mechanical frictional force between the overlapping portion and the base portion 22A by selecting the material of the displacement absorbing portion 32MD and processing the contact surfaces of the base portion 22A and the displacement absorbing portion 32MD. The inertial force of an object to be detected as an obstacle can be determined. And the impact force which the obstacle receives at the time of an obstacle (for example, person) and bumper 31M contact can be adjusted to an appropriate level. Similarly, the designer can determine the inertial force of an object to be detected as an obstacle by adjusting the magnitude of the biasing force by the biasing element 34M. Therefore, the impact force that the obstacle receives does not depend on the size and mass of the self-propelled vehicle 100.

  The displacement conversion unit 40 is a functional element that displaces another member using the displacement of a predetermined member. In the present embodiment, the displacement conversion unit 40 mechanically interrupts transmission of the driving force from the driving force generation unit 20 to the driving wheel 12 using the displacement of the obstacle detection unit 30M. Specifically, the displacement conversion unit 40 converts the displacement of the obstacle detection unit 30M into a relative displacement between the driving force generation unit 20 and the driving wheel 12. The displacement conversion unit 40 moves the driving force generation unit 20 away from the driving wheel 12, that is, moves the motor support unit 22 away from the base 11, thereby reducing the driving force from the driving force generation unit 20 to the driving wheel 12. Block transmission.

  Further, the displacement conversion unit 40 is configured not to move the motor support unit 22 away from the base 11 if the displacement of the obstacle detection unit 30M is less than a predetermined size. This configuration is mainly caused by the overlap between the displacement absorbing portion 32MD and the base portion 22A of the motor support portion 22. As a result, the meshing between the driving wheel side gear 14 and the motor side gear 23 is maintained, and transmission of the driving force from the driving force generator 20 to the driving wheel 12 is continued. At this time, the motor support 22 is in a standard contact state. The standard contact state is a state in which the bottom surface (the −Z side surface) of the motor support portion 22 is in contact with the surface of the base 11 (the + Z side surface), for example, the state shown in FIG. 6.

  On the other hand, when the displacement of the obstacle detection unit 30M exceeds a predetermined magnitude, the displacement conversion unit 40 displaces the motor support unit 22 away from the base 11. Specifically, when the displacement of the obstacle detection unit 30M exceeds a predetermined size, the overlap between the displacement absorbing unit 32MD and the base 22A is released, and the motor support unit 22 is based on the surface (bottom surface) on the −Z side. 11 is in a lifted state that does not contact the surface (surface) on the + Z side. As a result, the meshing between the driving wheel side gear 14 and the motor side gear 23 is released, and transmission of the driving force from the driving force generating unit 20 to the driving wheel 12 is interrupted.

  More specifically, the displacement converter 40 mainly includes a compression spring 45, a compression spring support member 46, a motor support portion guide 47, and a displacement transmission member guide 48.

  The compression spring 45 generates a force that displaces the motor support portion 22 in the + Z direction. In the present embodiment, the compression spring 45 is fixed to the compression spring support member 46 at the −Z side end. The compression spring 45 is in a compressed state when the motor support portion 22 is in a standard contact state, that is, when the displacement absorbing portion 32MD and the base portion 22A overlap (engage), and attaches the motor support portion 22 in the + Z direction. It is fast. Then, when the engagement between the displacement absorbing portion 32MD and the base portion 22A is released, it expands and lifts the motor support portion 22 in the + Z direction.

  The compression spring support member 46 is a member that fixes the end portion of the compression spring 45 on the −Z side. In the present embodiment, the compression spring support member 46 is constituted by a stay attached to the surface (bottom surface) on the −Z side of the base 11. The compression spring 45 passes through a through hole 11H that penetrates the base 11 in the Z-axis direction.

  The motor support portion guide 47 is a member that guides the displacement of the motor support portion 22 in the Z-axis direction. In the present embodiment, the motor support portion guide 47 is composed of two guide pins (only one is visible in FIG. 6) extending in the Z-axis direction. Specifically, the motor support portion guide 47 extends through a through guide hole 22H formed in the base portion 22A of the motor support portion 22, and rotates around the three axes of the motor support portion 22 as well as the X axis direction and the Y axis direction. To prevent parallel translation.

  The displacement transmission member guide 48 is a member that guides the displacement transmission member 32M that slides in the X-axis direction. In the present embodiment, the displacement transmission member guide 48 is configured by forming a guide groove 48 </ b> G in a block-like member fixed to the base 11.

  FIG. 7 shows the movement of the driving force generation unit 20, the obstacle detection unit 30M, and the displacement conversion unit 40 when the self-propelled vehicle 100 comes into contact with an obstacle ahead in the traveling direction. FIG. 7 includes an upper diagram and a lower diagram, and shows the movement of each part in the order of the upper diagram and the lower diagram.

  As shown in the upper diagram of FIG. 7, the bumper 31M in contact with the obstacle is displaced in the −X direction against the force of the biasing element 34M (see arrow AR4). As a result, the displacement transmitting member 32M is displaced in the −X direction as indicated by the arrow AR5, and the displacement absorbing portion 32MD is displaced in the −X direction. When the magnitude of displacement in the −X direction of the displacement absorbing portion 32MD exceeds a predetermined magnitude, the engagement between the displacement absorbing portion 32MD and the base portion 22A of the motor support portion 22 is released. Specifically, when the displacement transmission member 32M is displaced in the −X direction, the displacement absorbing portion 32MD slides in the guide groove 48G of the displacement transmission member guide 48 in the −X direction. When the displacement of the displacement absorbing portion 32MD in the −X direction exceeds a predetermined size, the displacement absorbing portion 32MD that has pressed the base 22A that is about to float in the + Z direction is moved from above the base 22A. Removed.

  When the displacement absorbing portion 32MD is removed from above the base portion 22A, the motor support portion 22 is lifted in the + Z direction by the compression spring 45 supported by the compression spring support member 46, as shown in the lower diagram of FIG. Then, it is guided by the motor support guide 47 and displaced in the + Z direction. As a result, the motor side gear 23 that is key-coupled to the rotation shaft 21A of the motor 21 is displaced in the + Z direction as indicated by the arrow AR6, and the drive wheel-side gear 14 that is key-coupled to the rotation shaft 12A of the drive wheel 12. The engagement with is released.

  In this way, the displacement converter 40 blocks the transmission of the driving force from the driving force generator 20 to the driving wheel 12 using the displacement of the obstacle detector 30M. Specifically, the displacement conversion unit 40 uses the series of displacements caused by the displacement of the bumper 31M of the obstacle detection unit 30M in the −X direction without using electric power, from the motor 21 to the drive wheel 12. The transmission of the driving force is mechanically interrupted. The series of displacements includes the displacement transmitting member 32M and the displacement absorbing portion 32MD in the −X direction, and the motor support portion 22 in the + Z direction.

  Further, the self-propelled vehicle 100 generates a braking force for preventing the self-propelled vehicle 100 from traveling by inertia when the transmission of the driving force from the driving force generator 20 to the drive wheels 12 is cut off. Let Specifically, the self-propelled vehicle 100 stops the rotation of the drive wheels 12 using a brake that operates according to the displacement of the obstacle detection unit 30M.

  For example, the self-propelled vehicle 100 has a normally closed switch that is in a cut-off state (open state) only when the obstacle detection unit 30M detects an obstacle, and the normally closed switch is in a cut-off state. You may make it provide the brake which act | operates.

  With the above configuration, the self-propelled vehicle 100 mechanically interrupts transmission of the driving force from the driving force generation unit 20 to the driving wheels 12 when the obstacle detection unit 30M detects the obstacle. Specifically, the displacement of the obstacle detection unit 30M is converted into a relative displacement between the drive wheel side gear 14 and the motor side gear 23 by the displacement conversion unit 40, and the motor side gear 23 is separated from the drive wheel side gear 14. Thus, transmission of the driving force from the driving force generator 20 to the driving wheel 12 is mechanically interrupted. Therefore, the self-propelled vehicle 100 can more reliably prevent the main body 10 from colliding with an obstacle as compared with the electric collision prevention function.

  Further, the obstacle detection unit 30M absorbs the displacement of the bumper 31M when the displacement of the bumper 31M is less than a predetermined size, and does not transmit the displacement to the displacement conversion unit 40 until the displacement becomes a predetermined size. It has a displacement absorbing part 32MD. Therefore, the displacement converter 40 does not block the transmission of the driving force from the driving force generator 20 to the driving wheels 12 until the displacement of the bumper 31M reaches a predetermined magnitude. As a result, the self-propelled vehicle 100 can prevent an object with small inertia that should not be detected as an obstacle from being detected as an obstacle.

  Further, the displacement absorbing portion 32MD has an overlapping portion that presses down the base portion 22A that attempts to move in the + Z direction. The inertial force of the object to be detected as an obstacle is determined by the length of the overlapping portion in the X-axis direction. Therefore, the designer can adjust the inertial force of the object to be detected as an obstacle by adjusting the length of the displacement absorbing unit 32MD.

  In addition, the self-propelled vehicle 100 can adjust the impact force received by the obstacle to an appropriate level while allowing the obstacle to contact the obstacle detection unit 30M. Therefore, it is possible to promote a shift from the development concept of “how to prevent contact with an obstacle” to the development concept of “how to control the impact force at the time of contact”. As a result, it is possible to develop the development concept for collision safety and the actual usage pattern of the self-propelled vehicle 100 into a form that is easier to use.

  Next, the brake mechanism 50 mounted on the self-propelled vehicle 100 will be described with reference to FIG. FIG. 8 is a perspective view showing a configuration example of the brake mechanism 50. The left figure shows a state during normal running, and the right figure shows a state when power is cut off. For clarity, the motor side gear 23 is shown transparently.

  The brake mechanism 50 is a mechanism that brakes the rotation of the drive wheel 12, and mainly includes the brake bar 24 and the brake bar receiving groove 12G.

  The brake bar 24 is a rod-like member extending in the + Y direction from the + Y side surface of the upper wall portion 22B (see FIG. 6) of the motor support portion 22.

  The brake bar receiving groove 12G is a groove that can receive the brake bar 24. In the present embodiment, a plurality of brake bar receiving grooves 12 </ b> G are formed inside the drive wheel 12.

  As shown in the left diagram of FIG. 8, when the motor 21 is driven, the driving wheel 12 receives the driving force of the motor 21 through the driving wheel side gear 14 and the motor side gear 23 and rotates in the direction of the arrow AR7. At this time, the brake bar 24 is located in a space between the drive wheel side gear 14 and the end surface 12Ga of the brake bar receiving groove 12G, and does not hinder the rotation of the drive wheel 12.

  Thereafter, when the level difference detection unit 30 detects a descending level difference or the obstacle detection unit 30M detects an obstacle, the motor side gear 23 and the brake bar 24 together with the motor support unit 22 are shown in the right diagram of FIG. It is lifted in the + Z direction. When the motor side gear 23 is lifted in the + Z direction, the engagement between the drive wheel side gear 14 and the motor side gear 23 is released, and transmission of the drive force from the motor 21 to the drive wheel 12 is mechanically interrupted. When the brake bar 24 is lifted in the + Z direction, the brake bar 24 and the brake bar receiving groove 12G are engaged, and the rotation of the drive wheel 12 is stopped.

  Thus, the brake mechanism 50 uses the displacement in the + Z direction of the motor support 22 to mechanically block the transmission of the driving force from the motor 21 to the drive wheels 12. The rotation of the drive wheel 12 is mechanically stopped using the displacement in the + Z direction. Therefore, the brake mechanism 50 can more reliably prevent the drive wheel 12 from rotating due to inertia.

  The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited to the above-described embodiments, and various modifications and substitutions can be made to the above-described embodiments without departing from the scope of the present invention. Can be added.

  For example, in the above-described embodiment, the displacement conversion unit 40 displaces the motor support unit 22 in the + Z direction and separates the motor side gear 23 from the drive wheel side gear 14 to thereby reduce the driving force from the motor 21 to the drive wheel 12. Mechanically cut off transmission. However, the present invention is not limited to this configuration. For example, the displacement conversion unit 40 may displace the motor side gear 23 from the drive wheel side gear 14 by displacing the motor support unit 22 in a direction other than the + Z direction (for example, the Y axis direction). Depending on the arrangement of the motor support 22 on the base 11 or the positional relationship with other components, it may be easier to displace the motor support 22 in a direction other than the + Z direction than in the + Z direction. It is. Further, if the motor side gear 23 can be separated from the drive wheel side gear 14, it is not necessary to limit the displacement direction of the motor support portion 22 to the + Z direction. And the selectivity of the displacement direction of the motor support part 22 can raise the design freedom of the self-propelled vehicle 100.

  Further, the displacement conversion unit 40 may disengage the motor side gear 23 from the drive wheel side gear 14 by displacing the motor side gear 23 without displacing the motor support unit 22. Further, the displacement conversion unit 40 may disengage the drive wheel side gear 14 from the motor side gear 23 by displacing the drive wheel side gear 14 without displacing the motor support unit 22. Further, the displacement conversion unit 40 may disengage the drive wheel side gear 14 from the motor side gear 23 by displacing both the drive wheel side gear 14 and the motor side gear 23. Depending on the arrangement of the motor support portion 22 on the base 11 or the positional relationship with other constituent members, the motor support portion 22 may not be displaced. This is because it is not necessary to displace the motor support 22 if the motor 23 can be separated from the drive wheel side gear 14. And the selectivity of the displacement target can increase the design freedom of the self-propelled vehicle 100.

  In the above-described embodiment, the self-propelled vehicle 100 transmits driving force from the motor 21 to the driving wheel 12 via the driving wheel side gear 14 and the motor side gear 23. However, the present invention is not limited to this configuration. For example, in the self-propelled vehicle 100, instead of the driving wheel side gear 14 and the motor side gear 23, the motor 21 to the driving wheel 12 via other arbitrary power transmission mechanisms such as a pulley mechanism, a chain mechanism, and a clutch mechanism. A driving force may be transmitted. If the driving force can be transmitted from the motor 21 to the driving wheel 12 and the transmission of the driving force can be interrupted by displacing any member, the power transmission mechanism need not be limited to the gear mechanism. It is. The selectivity of the power transmission mechanism can increase the degree of design freedom of the self-propelled vehicle 100.

  In the above-described embodiment, the level difference detection unit 30 converts the displacement of the driven wheel 31 in the −Z direction into the displacement of the displacement absorbing unit 32D in the + Z direction through the turning motion of the displacement transmission member 32. And amplify. However, the present invention is not limited to this configuration. For example, the level difference detection unit 30 may convert the displacement of the driven wheel 31 in the −Z direction into the displacement of another displacement absorbing unit through the linear motion of another displacement transmission member. Further, the level difference detection unit 30 does not necessarily amplify the displacement of the driven wheel 31 and may reduce the displacement.

  In the above-described embodiment, the obstacle detection unit 30M converts the displacement of the bumper 31M in the −X direction into the displacement of the displacement transmission member 32M and the displacement absorption unit 32MD in the −X direction. However, the present invention is not limited to this configuration. For example, the obstacle detection unit 30M may convert the displacement of the bumper 31M in the −X direction into the displacement of another displacement absorbing unit through the rotational movement or linear movement of another displacement transmission member. The obstacle detection unit 30M may amplify or reduce the displacement of the bumper 31M.

  In the above-described embodiment, the displacement conversion unit 40 is started (triggered) when the engagement between the groove 32Da of the displacement absorbing unit 32D and the slide pin 42 is released. Specifically, the slide pin 42 as the trigger member is slid by the tension spring 43, and the motor support portion 22 is lifted by the compression spring 45. Alternatively, the displacement conversion unit 40 is started (triggered) when the overlap between the displacement absorbing unit 32MD and the base 22A of the motor support unit 22 is released. However, the present invention is not limited to this configuration. For example, the operation may be started using a trigger member other than the slide pin 42 and the displacement absorbing portion 32MD. Further, the slide of the slide pin 42 and the displacement absorbing portion 32MD may be replaced by the rotational movement of another trigger member. Moreover, the motor support part 22 may be rotated instead of being lifted. In addition, permanent magnets, mainspring springs, accumulators, or the like may be used instead of mechanical elements such as the tension spring 43 and the compression spring 45.

  The self-propelled vehicle 100 according to the embodiment of the present invention may be applied to a self-propelled cleaning robot.

  DESCRIPTION OF SYMBOLS 10 ... Main-body part 11 ... Base 11H ... Through-hole 12 ... Drive wheel 12A ... Rotating shaft 12G ... Brake-bar receiving groove 12Ga ... End surface 14 ... Drive wheel side gear DESCRIPTION OF SYMBOLS 20 ... Driving force generation part 21 ... Motor 21A ... Rotating shaft 22 ... Motor support part 22A ... Base part 22B ... Upper wall part 22C ... Space 22H ... Through guide hole 23 ... motor side gear 24 ... brake bar 30 ... step detection part 30M ... obstacle detection part 31 ... driven wheel 31A ... rotary shaft 31M ... bumper 32, 32M Displacement transmission member 32A ... Rod-shaped part 32B ... Driven wheel support part 32C ... Turning connection part 32D, 32MD ... Displacement absorption part 32Da ... Groove part 33 ... Turning axis support member 34, 4M: Biasing element 35, 35M: Biasing element support member 40 ... Displacement conversion part 41 ... Slide pin guide 41H ... Through guide hole 42 ... Slide pin 42A ... Head Part 42B ... Neck part 42C ... Holding part 43 ... Tension spring 44 ... Tension spring support member 45 ... Compression spring 46 ... Compression spring support member 47 ... Motor support part guide 48 ... Displacement transmission member guide 48G ... Guide groove 50 ... Brake mechanism 100 ... Self-propelled vehicle

Claims (6)

Driving wheels,
A driving force generator for generating a driving force for driving the driving wheel;
A displacement detector that displaces when an obstacle in the direction of travel is reached,
A displacement converter that uses the displacement of the displacement detector to block transmission of the driving force from the driving force generator to the driving wheel;
Self-propelled vehicle with The displacement converter does not block transmission of driving force from the driving force generator to the driving wheel until the displacement of the displacement detector becomes a predetermined magnitude.
The self-propelled vehicle according to claim 1. The displacement converter converts the displacement of the displacement detector into a relative displacement between the driving force generator and the driving wheel, thereby transmitting the driving force from the driving force generator to the driving wheel. Shut off
The displacement detector absorbs the displacement when the displacement of the displacement detector is less than a predetermined size, and does not transmit the displacement to the displacement converter until the displacement reaches a predetermined size. Including parts,
The self-propelled vehicle according to claim 1 or 2. The obstacle is a step down,
The displacement absorber has an extension that is displaced according to the displacement of the displacement detector and extends along the direction of the displacement, and the depth of the recess to be detected as a downward step by the length of the extension. Is determined,
The self-propelled vehicle according to claim 3. An urging element that urges the displacement detector;
The biasing element promotes displacement of the displacement detection unit when the displacement detection unit is positioned at a step.
The self-propelled vehicle according to claim 4. The displacement absorbing unit is displaced according to the displacement of the displacement detection unit, and when the displacement detection unit receives a force greater than a predetermined force and is displaced to a predetermined magnitude or more, the displacement is transferred to the displacement conversion unit. Tell,
The self-propelled vehicle according to claim 3.

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