POSITION CONTROL DEVICE

Abstract

Position control device for controlling the position of a loading platform (21; 121; 321) in a mobile object (20), wherein the loading platform (21; 121; 321) comprises: a loading section (30; 130; 230; 330) which includes a section suitable for being loaded with a load; a base section (40) arranged below the loading section (30; 130; 230; 330) in such a way as to support the loading section (30; 130; 230; 330); and a coupling section (50; 150; 250) comprising a restoring element (51), wherein the restoring element (51) generates a restoring force to return the coupling section (50; 150; 250) to its original length when the coupling section (50; 150; 250) is stretched, wherein the coupling section (50; 150; 250) couples the base section (40) and the charging section (30; 130; 230; 330) via the restoring element (51) arranged between the base section (40) and the charging section (30; 130; 230; 330), the loading section (30; 130; 230; 330) and the base section (40) are arranged such that a lower part of the loading section (30; 130; 230; 330) and an upper part of the base section (40) face each other, and one of the upper part of the base section (40) and the lower part of the loading section (30; 130; 230; 330) comprises a spherical surface that is convex downwards, and the other of the upper part of the base section (40) and the lower part of the loading section (30; 130; 230; 330) comprises a guide section (42), wherein the guide section (42) guides the base section (40) and the loading section (30; 130; 230; 330) such that the base section (40) and the loading section (30; 130; 230; 330) are movable in a direction along the spherical surface relative to each other, characterized by a rotation position change mechanism (60) which causes the loading section (30; 130; 230; 330), the base section (40) and the coupling section (50 150; 250) to rotate integrally relative to a main body (22) of the mobile object (20) about a rotation axis extending in a first direction in which the base section (40) and the loading section (30; 130; 230; 330) are arranged.

Description

STATE OF THE ART

[0001] The present disclosure relates to a position control device that controls the position of a loading platform in a mobile object.

[0002] A vehicle such as an automobile typically includes a seat designed for an occupant to sit on. A vehicle seat includes a backrest portion against which an occupant rests their back, and a seat portion on which the occupant sits. A vehicle seat has a function for changing the angle of the backrest portion, a function for changing the angle of the seat portion, and the like (see Japanese Patent Application Laid-Open No. JP 2021-146831 A). In a vehicle, it is possible to adjust the position of a seat, and thus the position of a seated occupant, in accordance with the occupant's preference or the usage situation of the vehicle. US 2019 / 0381914 A1 discloses a position control device for controlling a position of a loading platform in a mobile object according to the preamble of claim 1.The documents JP 2006-199118 A, GB 2 438 826 A, DE 10 2016 009 452 A1, KR 10-0589431 B1 and DE 10 2018 222 635 A1 disclose further position control devices.

[0003] As vehicles incorporate advanced features, it is desirable for vehicle seats to also incorporate advanced features to improve ride comfort. It is desirable for advanced features to be incorporated not only into position control devices that control the position of a vehicle seat, but also into a position control device that controls the position of a loading platform in a mobile object, such as a position control device that controls the position of a loading platform provided in an automated guided vehicle. Based on US 2019 / 0381914 A1, it is an object of the present invention to provide a position control device for controlling a position of a loading platform in a mobile object, wherein a home position of a loading portion of a loading platform can be adjusted very flexibly. SUMMARY OF REVELATION

[0004] In a general aspect, a position control device is designed to control a position of a loading platform in a mobile object. The loading platform includes a loading section including a portion adapted to be loaded with a load, a base section disposed below the loading section to support the loading section, and a coupling section including a restoring element. The restoring element generates a restoring force for restoring the coupling section to its original length when the coupling section is stretched. The coupling section couples the base section and the loading section, with the restoring element being disposed between the base section and the loading section. The loading section and the base section are disposed such that a lower part of the loading section and an upper part of the base section face each other.One of the upper part of the base portion and the lower part of the loading portion includes a spherical surface that is downwardly convex, while the other of the upper part of the base portion and the lower part of the loading portion includes a guide portion. The guide portion guides the base portion and the loading portion such that the base portion and the loading portion are movable relative to each other in a direction along the spherical surface. A rotational position changing mechanism causes the loading portion, the base portion, and the coupling portion to rotate integrally relative to a main body of the mobile object about a rotation axis extending in a first direction in which the base portion and the loading portion are arranged. SHORT DESCRIPTION OF DRAWINGS

[0005] The features of the present disclosure believed to be novel are set forth with particularity in the appended claims. The disclosure, together with its objects and advantages, may best be understood by reference to the following description of preferred embodiments taken in conjunction with the drawings, in which: Fig. 1 is a schematic diagram showing a position control device according to a first embodiment. Fig. 2 is a perspective view obliquely from below showing a loading section according to the first embodiment. Fig. 3 is a perspective view obliquely from above showing a base portion according to the first embodiment. Fig. 4 is a schematic diagram of the position control device, showing a state in which the loading section is moved forward with respect to the base section. Fig. 5 is a schematic diagram of the position control device, showing a state in which a seat body is moved forward with respect to a mobile section. Fig. 6 is a schematic diagram showing a position control device according to a second embodiment. Fig. 7 is a perspective view from obliquely below showing a loading section according to the second embodiment. Fig. 8 is a schematic diagram showing a relative position changing mechanism according to the second embodiment. Fig. 9 is a schematic diagram of a seat showing a state in which the loading section is moved forward with respect to the base section. Fig. 10 is a schematic diagram of the seat showing a state in which the loading section is moved to the left with respect to the base section. Fig. 11 is a schematic diagram showing a position control device according to another embodiment. Fig. 12 is a schematic diagram showing the structure of a loading platform with which a position control device according to still another embodiment is used. DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment

[0006] The following is a position control device according to a first embodiment with reference to the Fig. 1 to 5 described. Vehicle 20

[0007] As it is in Fig. As shown in Figure 1, a vehicle 20 includes a seat 21 configured to accommodate an occupant. The seat 21 is attached to a vehicle body 22. In the present embodiment, the vehicle 20 corresponds to a mobile object, the seat 21 corresponds to a loading platform, the vehicle body 22 corresponds to a main body of the mobile object, and an occupant corresponds to a load.

[0008] The seat 21 includes a loading section 30 on which an occupant sits and a base section 40 that supports the loading section 30 from below. Loading section 30

[0009] As it is in the Fig. 1 and Fig. As shown in Figure 2, the loading section 30 includes a seat section 30S on which the occupant sits, and a backrest section 30B against which the occupant leans his or her back. The loading section 30 has a structure in which the seat section 30S and the backrest section 30B are integrally formed.

[0010] The loading section 30 includes a lower convex portion 33. The lower convex portion 33 includes a lower part of the seat portion 30S and a rear part of the backrest portion 30B. An outer surface (hereinafter referred to as a support surface 33A) of the lower convex portion 33 has a shape that protrudes in a direction away from the occupant sitting on the loading section 30, that is, a shape that is curved downward. In the present embodiment, the support surface 33A of the lower convex portion 33 corresponds to a surface supported by the base portion 40. Substantially the entire support surface 33A forms a spherical surface that is convex downward in a direction away from the occupant sitting on the loading section 30. Base Section 40

[0011] As it is in the Fig. 1 and Fig. As shown in Figure 3, the base portion 40 is attached to the vehicle body 22. The base portion 40 has a substantially columnar outer surface extending in an up-down direction Z of the vehicle 20. The base portion 40 includes, at the upper end, an upper concave portion 41 that is concave downward. The inner surface of the upper concave portion 41 is substantially spherical.

[0012] The upper concave portion 41 includes a plurality of (forty-six in the present embodiment) guide portions 42 that guide the base portion 40 and the loading portion 30 so that the base portion 40 and the loading portion 30 are movable relative to each other. The guide portions 42 are arranged at intervals in directions along the support surface 33A of the loading portion 30, which has a spherical surface. Fig. 3 shows the base section 40 in a state in which the guide sections 42 are not yet attached. As shown in Fig. 3, the upper concave portion 41 includes mounting holes 42A. The guide portions 42 ( Fig. 1) are attached to the mounting holes 42A.

[0013] As it is in Fig. As shown in Figure 1, each guide portion 42 includes a housing 42B and a contact ball 42C. The housings 42B are supported by the support surface 33A of the upper concave portion 41. Each contact ball 42C has a spherical shape in contact with the support surface 33A of the lower convex portion 33 and is rotatably housed in the corresponding housing 42B. Freebears (registered trademark) can be used as the guide portions 42. The guide portions 42 are arranged at equal intervals on the entire inner surface of the upper concave portion 41.

[0014] In the present embodiment, when the charging section 30 is supported by the base section 40 (which is shown in Fig. 1), the contact balls 42C of the guide portions 42 disposed in the upper concave portion 41 of the base portion 40 come into contact with the support surface 33A of the lower convex portion 33 of the loading portion 30. In the present embodiment, the guide portions 42 allow the base portion 40 and the loading portion 30 to move relative to each other in directions along the support surface 33A of the loading portion 30, which has a spherical surface. Coupling section 50

[0015] A coupling portion 50, which is attached to the seat 21, couples or connects the base portion 40 to the charging portion 30. The coupling portion 50 extends in a first direction (in the present embodiment, the up-down direction Z), which is a direction in which the charging portion 30 and the base portion 40 are arranged. The base portion 40 includes a coupling recess 43 at a center in plan view. The coupling recess 43 extends in the up-down direction Z from the upper end to the vicinity of the lower end of the base portion 40. The coupling portion 50 is arranged within the coupling recess 43. The coupling portion 50 includes a spring portion 51, an upper coupling portion 52, and a lower coupling portion 53. Spring section 51

[0016] The spring portion 51 is a central portion in the up-down direction Z of the coupling portion 50. The spring portion 51 includes a compression coil spring. The axis of the compression coil spring extends in the up-down direction Z. The spring portion 51 is configured to expand and contract in the up-down direction Z. The spring portion 51 has a structure in which the compression coil spring therein is elastically deformed in a compression direction when the spring portion 51 is expanded. In the present embodiment, the spring portion 51 corresponds to a restoring element that generates a restoring force for returning the coupling portion 50 to its original length when the coupling portion 50 is expanded. Upper coupling section 52

[0017] The upper coupling portion 52 is a part (specifically, an upper part) of the coupling portion 50 on the side closer to the loading portion 30 in the up-down direction Z. The upper coupling portion 52 is arranged between the loading portion 30 and the spring portion 51 to connect the loading portion 30 to the upper part of the spring portion 51. The upper coupling portion 52 functions as a universal joint. Lower coupling section 53

[0018] The lower coupling portion 53 is a part (specifically, a lower part) of the coupling portion 50 on the side closer to the base portion 40 in the up-down direction Z. The lower coupling portion 53 is located between the base portion 40 and the spring portion 51, so as to couple the base portion 40 (specifically, a bottom wall 45 of the coupling recess 43) to the lower end of the spring portion 51. The lower coupling portion 53 functions as a universal joint. Operation or effect of the coupling section 50

[0019] During travel of the vehicle 20, inertial forces act on the seat 21 of the vehicle 20 and the occupant sitting on the seat 21 when the vehicle 20 accelerates, decelerates, turns, or travels on a rough road. In such cases, the guide portions 42 in the seat 21 of the present embodiment allow relative movement between the loading portion 30 and the base portion 40 of the seat 21. Further, in the seat 21 of the present embodiment, when the loading portion 30 and the base portion 40 move relative to each other, the spring portion 51 of the coupling portion 50 expands or contracts, so that the compression coil spring in the spring portion 51 is elastically deformed. This dampens the inertial force acting on the loading portion 30 of the seat 21.

[0020] Fig. 4 shows an example of a manner in which the coupling portion 50 operates during travel of the vehicle 20.

[0021] When the vehicle 20 decelerates, an inertial force acts on the seat 21 such that the loading section 30 moves forward. Fig. 4, the guide sections 42 allow, at the end of the deceleration of the vehicle 20, a movement of the seat section 30S of the loading section 30 to the front (left side in Fig. 4) of the seat 21 with respect to the base portion 40. At this time, the upper coupling portion 52 coupled to the loading portion 30 is pulled by the loading portion 30 so that the spring portion 51 falls to the front of the seat 21 as shown by an arrow A in Fig. 4. As the spring portion 51 expands, the compression coil spring in the spring portion 51 is elastically deformed in the compression direction. Thereafter, when the inertial force acting on the loading portion 30 decreases, the compression coil spring in the spring portion 51 is restored to its original length (length before compression deformation), and the spring portion 51 is restored to its original length (length before expansion). Therefore, the relative positions of the loading portion 30 and the base portion 40 also return to their original positions (positions before movement); in particular, the positions (shown in Fig. 1) before the inertial force associated with the deceleration of the vehicle 20 acts on the loading section 30.

[0022] During travel of the vehicle 20, in the seat 21 of the present embodiment, relative movement between the loading section 30 and the base section 40 is possible in all directions. For example, when the vehicle 20 accelerates, the seat section 30S of the loading section 30 moves toward the rear of the seat 21 with respect to the base section 40. Furthermore, when the vehicle 20 turns right, the seat section 30S of the loading section 30 moves toward the left side of the seat 21 with respect to the base section 40. When the vehicle 20 turns left, the seat section 30S of the loading section 30 moves toward the right side of the seat 21 with respect to the base section 40.In the seat 21 of the present embodiment, the spring portion 51 of the coupling portion 50 expands or contracts to dampen the inertial force acting on the loading portion 30 of the seat 21 even if the loading portion 30 and the base portion 40 move in any direction relative to each other during travel of the vehicle 20. Rotation position change mechanism 60

[0023] As it is in the Fig. 1 and Fig. 3, the vehicle 20 includes a rotational position changing mechanism 60. The rotational position changing mechanism 60 causes the seat 21 as a whole (the loading portion 30, the base portion 40, and the coupling portion 50) to rotate integrally relative to the vehicle body 22 about a rotation axis extending in the up-down direction Z.

[0024] The rotational position changing mechanism 60 includes a support portion 61. The support portion 61 is provided on the vehicle body 22 and has a cylindrical shape that protrudes upward. In the present embodiment, the lower part of the base portion 40 is received in the support portion 61 so that the inner peripheral surface of the support portion 61 and the outer peripheral surface of the base portion 40 of the seat 21 face each other.

[0025] The rotational position changing mechanism 60 includes a plurality of (six in the present embodiment) bearing portions 62. Each bearing portion 62 includes a rotary shaft 62A extending in the up-down direction Z and a cylindrical rotary portion 62B rotatably disposed around the rotary shaft 62A. The base portion 40 includes a groove (bearing groove 44) in the outer peripheral surface of the lower part. The bearing groove 44 extends over the entire circumference. In the present embodiment, the rotary shafts 62A of the bearing portion 62 are portions fixed to the upper end of the support portion 61 in a state where the outer peripheral part of the rotary portion 62B of each bearing portion 62 is fitted into the bearing groove 44 of the base portion 40. In this way, the bearing portions 62 are disposed between the support portion 61 and the base portion 40.The bearing portions 62 fix the base portion 40 to the support portion 61 in a manner in which the base portion 40 is rotatable within the support portion 61 and in a manner in which the base portion 40 cannot escape from the interior of the support portion 61.

[0026] The rotational position changing mechanism 60 includes a ring gear 63 provided on the base portion 40 and a pinion gear 64 meshing with the ring gear 63. The ring gear 63 is provided on the outer peripheral surface of the base portion 40 so as to extend in the circumferential direction. The pinion gear 64 is provided on the vehicle body 22 ( Fig. 1). The vehicle body 22 includes an electric motor (hereinafter referred to as a rotational position changing motor 65) for rotating the pinion gear 64, a controller 66 for controlling the operation of the rotational position changing motor 65, and a rotation operation switch 67. The rotation operation switch 67 is operated by an occupant when rotating the seat 21. Output signals from the rotation operation switch 67 are received by the controller 66. The controller 66 may be a circuit including: 1) one or more processors operating according to a computer program (software); 2) one or more dedicated hardware circuits (application-specific integrated circuits: ASIC) that execute at least some of various processes; or 3) a combination thereof. The processor includes a central processing unit (CPU) and a memory such as a random access memory (RAM) and a read-only memory (ROM).Memory stores program code or instructions that cause the CPU to execute processes. Memory, which is a computer-readable medium, includes any type of media that can be accessed by general-purpose and dedicated computers. Operation or effect of the rotation position change mechanism 60

[0027] The rotational position changing mechanism 60 operates as follows. When the rotation operation switch 67 is operated by the occupant, the control device 6 causes the rotational position changing motor 65 to rotate. Therefore, the rotational position changing mechanism 60 causes the base portion 40 to rotate relative to the vehicle body 22, together with the coupling portion 50 and the loading portion 30 integrated with the base portion 40. Coupling position change mechanism 70

[0028] As it is in the Fig. 1 and Fig. 2, the vehicle 20 includes a coupling position changing mechanism 70. The coupling position changing mechanism 70 changes the coupling position at which the coupling portion 50 is coupled to the loading portion 30 of the seat 21 in a front-rear direction Y of the seat 21 (specifically, in the front-rear direction of the occupant sitting on the seat 21).

[0029] A specific structure of the coupling position changing mechanism 70 is described below.

[0030] The loading section 30 of the seat 21 comprises a seat body 31 and a mobile section 32.

[0031] The seat body 31 forms a major portion of the loading portion 30. The seat body 31 includes a receiving hole 34 at a position corresponding to the support surface 33A. The receiving hole 34 extends from the lower surface of the seat portion 30S to the rear surface of the backrest portion 30B. The receiving hole 34 has an arcuate cross section and extends in the front-rear direction Y of the seat 21. The depth and width in the extending direction of the receiving hole 34 are substantially constant.

[0032] The mobile portion 32 has an arcuate cross section and extends in the front-rear direction Y of the seat 21. In the present embodiment, the mobile portion 32 is received in the receiving hole 34 of the seat body 31 such that the outer surface of the mobile portion 32 and the outer surface of the seat body 31 are substantially flush with each other and form the support surface 33A.

[0033] A sliding mechanism (not shown) is provided between the receiving hole 34 of the seat body 31 and the mobile portion 32. The mobile portion 32 is fixed in the receiving hole 34 with the sliding mechanism in a state where the mobile portion 32 can reciprocate in the front-back direction Y within the receiving hole 34 but cannot escape from the inside of the receiving hole 34. In the present embodiment, the upper end of the coupling portion 50 (specifically, the upper coupling portion 52) is fixed to the mobile portion 32.

[0034] The coupling position changing mechanism 70 includes a ring gear 71 provided on the seat body 31 and a pinion 72 ( Fig. 1) that is in meshing engagement with the ring gear 71. The ring gear 71 is provided on the bottom surface of the receiving hole 34 so as to extend in the front-rear direction Y of the seat 21. The pinion gear 72 is arranged in the mobile section 32. The mobile section 32 includes an electric motor (hereinafter referred to as a coupling position changing motor 73) for rotating the pinion gear 72, and a control device 74 for controlling the operation of the coupling position changing motor 73. The control device 74 may be a circuit including: 1) one or more processors that operate according to a computer program (software); 2) one or more dedicated hardware circuits (application-specific integrated circuits: ASIC) that execute at least part of various processes; or 3) a combination thereof.The processor includes a central processing unit (CPU) and memories such as random access memory (RAM) and read-only memory (ROM). The memories store program codes or instructions that cause the CPU to execute processes. The memory, which is a computer-readable medium, includes any type of media accessible by general-purpose computers and dedicated computers. A coupling operation switch 75 is mounted on a vehicle body 22. The coupling operation switch 75 is operated by the occupant when changing the inclination angle (position) of the loading section 30 of the seat 21 in the front-rear direction Y. Output signals of the coupling operation switch 75 are received by the controller 74. Operation and effect of the coupling position changing mechanism 70

[0035] The coupling position changing mechanism 70 operates as follows.

[0036] When the coupling operation switch 75 is operated by the occupant, the control device 74 causes the coupling position changing motor 73 to rotate. This causes the coupling position changing mechanism 70 to operate so that the mobile section 32 and the seat body 31 move relative to each other in the front-to-rear direction Y of the seat 21. The mobile section 32 is coupled to the base section 40 by the coupling section 50. Therefore, when the mobile section 32 and the seat body 31 move relative to each other, the coupling section 50 normally remains at the current position, and the seat body 31 moves in the front-to-rear direction Y. This changes the position of the loading section 30 (specifically, the seat body 31) of the seat 21 in the front-to-rear direction Y.

[0037] Fig. Fig. 5 shows an example of operation of the coupling position changing mechanism 70 when the seat body 31 is moved forward (shown by arrow B in the drawing) with respect to the mobile portion 32 of the seat 21. In this case, the front end of the seat portion 30S is raised, and the backrest portion 30B is tilted rearward, as shown in Fig. 5 is shown.

[0038] When the seat body 31 is moved rearward with respect to the mobile portion 32 of the seat 21, the front end of the seat portion 30S is lowered and the backrest portion 30B is raised and moved forward.

[0039] In the present embodiment, the rotational position changing mechanism 60 operates to move the position of the seat 21 (specifically, the seat body 31) in a basic state in which no inertial force acts on the loading section 30.

[0040] The present embodiment has the following advantages.

[0041] (1-1) The seat 21 includes the loading section 30, the base section 40, and the coupling section 50. The loading section 30 is arranged in the upper part of the base section 40 such that the support surface 33A of the lower convex section 33 of the loading section 30 faces the inner surface of the upper concave section 41 of the base section 40. The coupling section 50 includes the spring section 51 and couples the base section 40 to the loading section 30 with the spring section 51 sandwiched between them. The support surface 33A of the lower convex section 33 of the loading section 30 has a spherical surface. The inner surface of the upper concave section 41 of the base section 40 includes the guide sections 42.The guide portions 42 guide the base portion 40 and the loading portion 30 so that the base portion 40 and the loading portion 30 move relative to each other in a direction along the support surface 33A of the lower convex portion 33, which has a spherical surface.

[0042] As described above, when the vehicle 20 is traveling, an inertial force acts on the seat 21 and the passenger sitting on the seat 21. According to the present embodiment, when such an inertial force is generated, the guide portions 42 allow the loading portion 30 and the base portion 40 of the seat 21 to move relative to each other. When the loading portion 30 and the base portion 40 are moved relative to each other, the spring portion 51 of the coupling portion 50 expands or contracts to thereby dampen the inertial force acting on the loading portion 30 of the seat 21. This reduces the impact acting on the loading portion 30, thereby stabilizing the position of the loading portion 30 and the position of the passenger sitting on the loading portion 30.

[0043] (1-2) The seat 21 includes the coupling position changing mechanism 70 configured to change the coupling position at which the coupling portion 50 is coupled to the loading portion 30. When the coupling position changing mechanism 70 is activated by the occupant operating the coupling operation switch 75, the relative position of the base portion 40 to the loading portion 30 changes in the standard state in which no inertial force acts on the loading portion 30.

[0044] According to the present embodiment, the coupling position changing mechanism 70 enables the position of the loading section 30 in the home state (hereinafter referred to as a home position) to be adjusted so that the seating surface of the seating section 30S is horizontal, as shown in Fig. 1. Furthermore, as shown in the example in Fig. 5, it is also possible to adjust the home position of the loading section 30 so that the seat surface of the seat section 30S is inclined in the front-rear direction Y. In this way, the present embodiment allows flexible adjustment of the home position of the loading section 30.

[0045] (1-3) The vehicle 20 includes the rotation position changing mechanism 60. The rotation position changing mechanism 60 causes the seat 21 as a whole to rotate integrally with the vehicle body 22 about the rotation axis extending in the up-down direction Z.

[0046] According to the present embodiment, it is possible to freely change the orientation (specifically, the rotational position) of the seat 21 around the rotational axis extending in the up-down direction Z by activating the rotational position changing mechanism 60 by operating the rotation operation switch 67 by the occupant. This allows the home position of the loading section 30 of the seat 21 to be adjusted very flexibly. Second embodiment

[0047] The following is a position control device according to a second embodiment with reference to the Fig. 6 to 10, particularly discussing the differences from the first embodiment. In the following description, among the components of the position control device according to the present embodiment, the same components as those of the position control device according to the first embodiment are denoted by the same reference numerals or corresponding reference numerals, and redundant description of the components is omitted.

[0048] Unlike the position control device of the first embodiment, the position control device of the present embodiment does not include the coupling position changing mechanism 70 (see Fig. 1) or its peripheral devices. The position control device of the present embodiment differs from the position control device of the first embodiment in that it has a relative position changing mechanism that is controlled in accordance with the moving state of the vehicle.

[0049] The relative position change mechanism and the surrounding structure are described below. Loading section 130

[0050] As it is in the Fig. 6 and Fig. As shown in Fig. 7, a loading section 130 of a seat 121 has a structure in which a seat section 130S and a backrest section 130B are integrally formed. The loading section 130 includes a lower convex portion 133 comprising a lower part of the seat section 130S and a rear part of the backrest section 130B. An outer surface (hereinafter referred to as a support surface 133A) of the lower convex portion 133 has a spherical surface curved in a direction away from the occupant sitting on the loading section 130. The loading section 130 of the present embodiment includes no movable parts and is entirely formed in one piece. Relative position change mechanism 80

[0051] As it is in the Fig. 6 and Fig. 8, the seat 121 includes a relative position changing mechanism 80. The relative position changing mechanism 80 is disposed between a lower coupling portion 53 of the coupling portion 150 and a bottom wall 45 of a coupling recess 43 of the base portion 40 so as to form a central part of the coupling portion 150 in the up-down direction Z. The relative position changing mechanism 80 serves to displace the bottom wall 45 of the coupling recess 43 of the base portion 40 and the lower end of the lower coupling portion 53 relative to each other in a second direction intersecting the up-down direction Z (specifically, the second direction extends in a plane perpendicular to the up-down direction Z).In the present embodiment, the bottom wall 45 of the coupling recess 43 of the base portion 40, to which one end of the relative position changing mechanism 80 in the up-down direction Z is coupled, corresponds to a part closer to the base portion 40, and the lower end of the lower coupling portion 53, to which the other end of the relative position changing mechanism 80 is coupled, corresponds to a part closer to the loading portion 130.

[0052] Specifically, the relative position changing mechanism 80 includes a front-to-back direction changing mechanism 81 and a sideways direction changing mechanism 85. The front-to-back direction changing mechanism 81 displaces the bottom wall 45 of the base portion 40 and the lower end of the lower coupling portion 53 in the front-to-back direction Y of the seat 121. The sideways direction changing mechanism 85 displaces the bottom wall 45 and the lower end of the lower coupling portion 53 in a sideways direction X of the seat 121.

[0053] As it is in Fig. As shown in Fig. 8, a guide rail 82 extending in the front-to-back direction Y of the seat 121 is disposed on the bottom wall 45 of the base portion 40. A rectangular plate-shaped guide table 83 is fixed to the bottom wall 45 of the base portion 40, with the guide rail 82 being disposed between the bottom wall 45 and the base portion of the guide table 83. The guide table 83 is guided by the guide rail 82 to reciprocate in the front-to-back direction Y with respect to the base portion 40. The guide rail 82 and the guide table 83 constitute the front-to-back direction changing mechanism 81.

[0054] An electric motor (hereinafter referred to as a front-to-back direction motor 84) as a drive unit is connected to the guide table 83 via a gear mechanism (not shown). In the present embodiment, the guide table 83 is moved in the front-to-back direction Y by driving the front-to-back direction changing mechanism 81 through an operation control of the front-to-back direction motor 84.

[0055] A guide rail 86 is arranged on the upper surface of the guide table 83, extending in the sideways direction X of the seat 121. A rectangular plate-shaped guide table 87 is fixed to the upper surface of the guide table 83, and the guide rail 86 is arranged between the guide table 87 and the upper surface of the guide table 83. The guide table 87 is guided by the guide rail 86 to reciprocate in the sideways direction X with respect to the base portion 40 (specifically, the guide table 83). The guide rail 86 and the guide table 87 constitute the sideways direction changing mechanism 85.

[0056] An electric motor (hereinafter referred to as a sideways direction motor 88) as a drive unit is connected to the guide table 87 via a gear mechanism (not shown). In the present embodiment, the guide table 87 is moved in the sideways direction X by driving the sideways direction changing mechanism 85 through an operation control of the sideways direction motor 88. Control device 90

[0057] As it is in Fig. 6, the vehicle 20 includes a controller 90 for controlling the operation of the front-to-rear direction motor 84 and the side-to-side direction motor 88. The controller 90 may be a circuit including: 1) one or more processors operating according to a computer program (software); 2) one or more dedicated hardware circuits (application-specific integrated circuits: ASICs) that execute at least a portion of various processes; or 3) a combination thereof. The processor includes a central processing unit (CPU) and memories such as random access memory (RAM) and read-only memory (ROM). The memories store program codes or instructions that cause the CPU to execute processes. The memory, which is a computer-readable medium, includes any type of media accessible by general-purpose computers and dedicated computers.The vehicle 20 includes various sensors that detect the behavior of the vehicle 20, such as a gyroscope sensor 91 and an acceleration sensor 92. Detection signals from various sensors are supplied to the control device 90. The vehicle 20 further includes a navigation system 93. In the present embodiment, the navigation system 93 outputs position information and map information as output signals received by the control device 90.

[0058] The control device 90 performs various calculations based on the output signals of the various sensors and the navigation system 93, and controls the operation of the front-rear direction motor 84 and the side-to-side direction motor 88 based on the calculation results. In the present embodiment, the various sensors and the navigation system 93 correspond to a detection unit, the output signals of the various sensors and the navigation system 93 correspond to information about a moving state of a mobile object, and the control device 90 corresponds to a control unit. Operation and effect of the relative position change mechanism 80

[0059] The relative position changing mechanism 80 operates as follows.

[0060] When the control device 90 controls the operation of the front-to-back direction motor 84 to operate the front-to-back direction changing mechanism 81, the lower part of the coupling portion 150 moves in the front-to-back direction Y with respect to the base portion 40. At this time, the loading portion 130 of the seat 121 is pulled by the coupling portion 150 coupled to the loading portion 130, so as to move in the front-to-back direction Y together with the coupling portion 150. Thereby, the loading portion 130 of the seat 121 is moved in a direction along the outer surface of the spherical lower convex portion 133.

[0061] Fig. Fig. 9 shows an example of how the position of the loading section 130 of the seat 121 is changed when the front-rear direction changing mechanism 81 moves the guide table 83 and the coupling section 150 forward. The long-short-short-dashed line in Fig. 9 represents the basic position of the loading section 130 of the seat 121, and the solid line in Fig. 9 represents the position of the loading section 130 of the seat 121 when the front-rear direction change mechanism 81 is activated. In Fig. 9, the amounts of movement of the guide table 83, the coupling section 150 and the loading section 130 are exaggerated for better understanding.

[0062] As it is in Fig. 9, when the front-rear direction changing mechanism 81 is operated to move the guide table 83 and the coupling portion 150 forward, the front end of the seat portion 130S of the seat 121 is lifted (the state represented by the solid line in the drawing) and the backrest portion 130B is tilted rearward.

[0063] When the front-rear direction changing mechanism 81 is operated to move the guide table 83 and the coupling portion 150 rearward with respect to the base portion 40, the front end of the seat portion 130S of the seat 121 is lowered and the backrest portion 130B is raised in a forward direction.

[0064] Further, when the operation of the sideways direction motor 88 is controlled by the control device 90 to operate the sideways direction changing mechanism 85, the lower part of the coupling portion 150 moves in the sideways direction X with respect to the base portion 40. At this time, the loading portion 130 of the seat 121 is pulled by the coupling portion 150 coupled to the loading portion 130, so as to move in the sideways direction X together with the coupling portion 150. Thereby, the loading portion 130 of the seat 121 is moved in a direction along the outer surface of the spherical lower convex portion 33.

[0065] Fig. Fig. 10 shows an example of how the position of the loading section 130 of the seat 121 is changed when the sideways direction changing mechanism 85 moves the guide table 87 and the coupling section 150 forward. The long-short-dashed line in Fig. 10 represents the basic position of the loading section 130 of the seat 121, and the solid line in Fig. 10 represents the position of the loading section 130 of the seat 121 when the sideways direction changing mechanism 85 is actuated. In Fig. 10, the amounts of movement of the guide table 87, the coupling section 150 and the loading section 130 are exaggerated for better understanding.

[0066] As it is in Fig. 10, when the sideways direction changing mechanism 85 moves the guide table 87 and the coupling portion 150 to the left with respect to the base portion 40, the seat surface of the seat portion 130S is inclined so that the left side of the seat portion 130S is raised.

[0067] When the sideways direction changing mechanism 85 moves the guide table 87 and the coupling portion 50 to the right with respect to the base portion 40, the seat surface of the seat portion 130S is inclined so that the right side of the seat portion 130S is raised.

[0068] In the present embodiment, the front-to-rear direction changing mechanism 81 and the side-to-side direction changing mechanism 85 operate together when the control device 90 simultaneously controls the operation of the front-to-rear direction motor 84 and the operation of the side-to-side direction motor 88. In this case, the coupling portion 150 can be moved in any direction with respect to the base portion 40. Thus, the loading portion 130 of the seat 121 can also be moved in any direction together with the coupling portion 150 by being pulled by the coupling portion 150 coupled to the loading portion 130.

[0069] The control device 90 performs the operation control of the front-rear direction motor 84 and the operation control of the side-to-side direction motor 88 as follows. Control example 1

[0070] The loading section 130 is moved in accordance with the actual behavior of the vehicle 20 so as to compensate for the shocks exerted on the seat 121.

[0071] For example, when a deceleration of the vehicle 20 is detected, the front-rear direction change mechanism 81 operates in accordance with the deceleration to move the coupling portion 150 forward. In this case, since the loading portion 130 of the seat 121 is pulled and moves forward in accordance with the deceleration of the vehicle 20, the impact exerted on the seat 121 and the passenger on the seat 121 is reduced.

[0072] Further, when it is detected that the vehicle 20 is turning right, the sideways direction changing mechanism 85 operates in accordance with the right turn to move the coupling portion 150 to the left. In this case, since the loading portion 130 of the seat 121 is pulled and moves to the right in accordance with the right turn of the vehicle 20, the impact exerted on the seat 121 and the passenger is reduced. Control example 2

[0073] The moving state of the vehicle 20 is predicted based on information (position information and map information) obtained by the navigation system 93, and the position of the charging section 30 is controlled in accordance with the predicted moving state.

[0074] For example, at a time when the vehicle 20 is predicted to reach a corner, the sideways direction changing mechanism 85 moves the coupling portion 150 outward with respect to the turning direction. In this case, when the vehicle 20 is about to turn, the position of the seat 121 and the position of the occupant sitting on the seat 121 are preliminarily adjusted to positions inclined inward with respect to the turning direction in preparation for the vehicle 20 to turn.

[0075] The present embodiment has the following advantages.

[0076] (2-1) The seat 121 includes the relative position changing mechanism 80. The relative position changing mechanism 80 is for displacing the bottom wall 45 of the coupling recess 43 of the base portion 40 and the lower end of the lower coupling portion 53 relative to each other in the second direction intersecting the up-down direction Z. The vehicle 20 includes the front-back direction motor 84 and the side-to-side direction motor 88 that actuate the relative position changing mechanism 80, and the control device 90 that controls the operation of the motors 84, 88. The vehicle 20 includes various sensors and the navigation system 93 used to obtain information about the moving state of the vehicle 20.The control device 90 controls the operation of the motors 84, 88 based on the information about the state of motion of the vehicle 20 determined by the various sensors and the navigation system 93, thereby causing activation of the relative position changing mechanism 80.

[0077] According to the present embodiment, it is possible to very flexibly control the position of the loading section 130 of the seat 121. For example, the position of the loading section 130 can be controlled in accordance with the actual traveling state of the vehicle 20. Furthermore, the position of the loading section 130 can be controlled in advance in accordance with a predicted traveling state of the vehicle 20. Therefore, it is possible to precisely control the position of the seat 121 and the position of the occupant sitting on the seat 121 in accordance with the situation.

[0078] (2-2) The present embodiment achieves the same advantages as those described in the above-described items (1-1) and (1-3). Further embodiments

[0079] The above-described embodiments may be modified as follows. The above-described embodiments and the following modifications may be combined as long as the combined modifications remain technically consistent with each other.

[0080] In the first embodiment, the coupling position changing mechanism 70 is not limited to a ring-and-pinion mechanism with the ring gear 71 on the seat body 31 and the pinion gear 72 on the mobile portion 32, but can be any mechanism. That is, any mechanism can be used as a coupling position changing mechanism as long as it has a structure capable of changing the coupling position at which the coupling portion 50 is coupled to the charging portion 30.

[0081] Fig. 11 shows a coupling position changing mechanism 270 as an example. As shown in Fig. As shown in FIG. 11, a hook 276 is provided in this example at an end portion of the upper coupling portion 52 of a coupling portion 250 on the loading portion 230 side. The loading portion 230 includes a through-hole 235. The coupling portion 250 is inserted into the through-hole 235. The loading portion 230 includes recesses (hereinafter referred to as locking recesses 236) at the upper edge of the through-hole 235. The hook 276 is hooked into one of the locking recesses 236. The locking recesses 236 are arranged at intervals in the front-rear direction Y at a plurality of locations (seven locations in this example). In the coupling position changing mechanism 270 of the present example, the hook 276 of the coupling portion 250 is hooked into a selected one of the locking recesses 236 so as to adjust the position of the loading portion 230 in the front-rear direction Y in multiple stages.

[0082] In the first embodiment, the coupling position changing mechanism 70 has a structure capable of changing the coupling position at which the coupling portion 50 is coupled to the charging portion 30. However, the present disclosure is not limited to this. For example, a mechanism capable of changing the coupling position at which the coupling portion 50 is coupled to the base portion 40 may be used.

[0083] In the second embodiment, the operation of the rotational position changing motor 65 corresponding to the rotational position changing mechanism 60, along with the operation of the motors 84, 88 corresponding to the relative position changing mechanism 80, can be controlled based on information about the moving state of the vehicle 20. With this configuration, in addition to controlling the position of the seat 121 in the front-rear direction Y and the sideways direction X, it is possible to control the orientation of the seat 121 around the rotation axis extending in the up-down direction Z. This enables highly flexible control of the position of the loading section 130 of the seat 121.

[0084] In the second embodiment, any suitable device, for example, a camera, a radar sensor, or a LiDAR sensor may be used as the detection unit for detecting the information about the moving state of the vehicle 20.

[0085] In the second embodiment, the arrangement position of the relative position changing mechanism 80 can be changed to any position as long as the relative position changing mechanism 80 forms a central part of the coupling portion 50 in the up-down direction Z. For example, the relative position changing mechanism 80 may be arranged between the lower coupling portion 53 and the spring portion 51, or between the upper coupling portion 52 and the loading portion 130.

[0086] In the second embodiment, the drive unit that operates the relative position changing mechanism 80 may be a hydraulic actuator, a pneumatic actuator, or the like instead of an electric motor.

[0087] In the second embodiment, one of the front-rear direction changing mechanism 81 and the sideways direction changing mechanism 85 may be omitted.

[0088] In the second embodiment, the relative position changing mechanism 80, that is, both the front-to-back direction changing mechanism 81 and the side-to-side direction changing mechanism 85, may be omitted. In this case, the lower end of the lower coupling portion 53 may be coupled to the bottom wall 45 of the base portion 40.

[0089] In each of the embodiments, a portion of the outer surface of the lower convex portion 33, 133 may have a shape other than a spherical surface. For example, an edge portion of the lower convex portion 33, 133 of the loading portion 30, 130 may have a shape other than a spherical surface. That is, the shape of the outer surface of the lower convex portion 33, 133 may be changed as long as all portions of the outer surface of the lower convex portion 33, 133 that are in contact with the respective guide portions 42 form the same spherical surface.

[0090] In each embodiment, the inner surface of the upper concave portion 41 of the base portion 40 is not limited to a substantially spherical surface, but can be formed into any shape. Furthermore, it is also possible to use a base portion 40 having a structure without the upper concave portion 41. That is, the upper structure of the base portion 40 can be changed as long as the guide portions 42 can be arranged so that the portions of the guide portions 42 that are in contact with the lower convex portions 33, 133 are aligned on the same spherical surface.

[0091] In any of the embodiments, the guide portions 42 may be disposed in the lower convex portion 33 of the loading portion 30 instead of in the upper concave portion 41 of the base portion 40. In this configuration, the inner surface of the upper concave portion 41 of the base portion 40 may be formed into a substantially spherical surface. In this configuration, the inner surface of the upper concave portion 41 corresponds to a surface that supports the loading portion 30. Furthermore, in the above-described configuration, the guide portions 42 may be disposed in the lower part of the loading portion 30 so that portions of the guide portions 42 that are in contact with the upper concave portion 41 are disposed on the same spherical surface.In this case, the part of the outer surface of the loading section 30 below the seat section 30S and the rear part of the backrest section 30B are not limited to being substantially spherical, but may have any shape.

[0092] In none of the embodiments are the guide portions 42 limited to including the housing 42B and the contact ball 42C, but may include any suitable structure. For example, the inner surface of the upper concave portion 41 of the base portion 40 may be formed as a spherical surface, and the inner surface of the upper concave portion 41 may be used as a guide portion. In this case, the loading portion 30, 130 may be arranged on the base portion 40 such that the lower convex portion 33, 133 of the loading portion 30, 130 is received by the upper concave portion 41 of the base portion 40.In this case, in order to improve sliding, it is advantageous to supply (apply) a lubricant (oil, grease) or to introduce compressed air between the inner surface of the upper concave portion 41 of the base portion 40 and the outer surface of the lower convex portion 33, 133 of the loading portion 30, 130.

[0093] In any of the embodiments, the spring portion 51 may be a shock absorber in which the damping force in a compression direction is smaller than the damping force in an extension direction, instead of a type including a compression coil spring.

[0094] In any of the embodiments, the structure of the rotational position changing mechanism 60 can be changed as long as the structure causes the seat 21, 121 to rotate integrally relative to the vehicle body 22. For example, a rotational position changing mechanism may be used that includes a ring gear disposed on the inner peripheral surface of the support portion 61 and a pinion rotatably disposed on the base portion 40 and meshing with the ring gear.

[0095] In each of the embodiments, a manually operated type may be used as the rotation position changing mechanism 60.

[0096] The position control device according to each of the embodiments can also be used as a position control device for a mobile object other than an automobile, such as a position control device for controlling the position of a seat in a wheelchair and a position control device for controlling the position of a loading platform in an automatic guided vehicle.

[0097] When the position control device according to each of the embodiments is used in a wheelchair, the position of the seat (particularly its loading section) and thus the position of the user sitting on the seat is stabilized.

[0098] Fig. Fig. 12 shows an example of the structure of a loading platform in a housing in which the position control device according to each of the embodiments is used in an automatically guided vehicle. As shown in Fig.As shown in Fig. 12, a loading platform 321 includes a base portion 40 and a loading portion 330. An upper part of the loading portion 330 is a flat plate portion 330S in the shape of a flat plate. A lower part of the loading portion 330 is a lower convex portion 333 having a spherical outer surface. The loading portion 330 is located on the upper part of the base portion 40 such that the outer surface of the lower convex portion 333 of the loading portion 330 and the inner surface of the upper concave portion 41 of the base unit 40 face each other. With this configuration, the impact acting on the loading portion 330 is reduced and the position of the loading portion 330 and thus the position of the cargo loaded on the loading portion 330 is stabilized.

[0099] Although only several embodiments are described herein, it will be apparent to those skilled in the art that the present disclosure may be embodied in other ways without departing from the spirit of the disclosure. The disclosure is not limited to the details given herein, but may be modified within the scope and equivalents of the appended claims. List of reference symbols A Arrow B Arrow Z Top-bottom direction 20 vehicles 21 seats 22 vehicle body 30 loading section 30B Backrest section 30S seat section 33 lower convex section 33A support surface 40 Base Section 41 upper concave section 42 Guide Section 42A mounting hole 42B housing 42C contact ball 43 Coupling recess 44 bearing groove 45 floor wall 50 coupling section 51 spring section 52 upper coupling section 53 lower coupling section 60 Rotation position change mechanism 61 support section 62 storage section 62A rotating shaft 62B turning section 63 sprocket 64 pinions 65 Rotary position change motor 66 Control device 67 rotary operating switches 70 Coupling position change mechanism 71 sprocket 72 pinions 73 Coupling position change motor 74 Control device 75 coupling actuation switch 80 Relative position change mechanism 81 Front-rear direction change mechanism 82 guide rail 83 Management table 84 Front-rear direction motor 85 Sideways direction change mechanism 86 guide rail 87 Management table 88 Sideways direction motor 90 Control device 91 Gyroscope sensor 92 Accelerometer 93 Navigation system 121 seats 130 loading section 130S seat section 130B Backrest section 133 lower convex section 133A Support surface 150 coupling section 230 loading section 235 through hole 236 locking recess 250 coupling section 270 Coupling position change mechanism 276 hooks 321 loading platform 330 loading section 330S flat plate section

Claims

[1] Position control device for controlling a position of a loading platform (21; 121; 321) in a mobile object (20), the loading platform (21; 121; 321) comprising: a loading section (30; 130; 230; 330) comprising a section adapted to be loaded with a load; a base portion (40) disposed below the loading portion (30; 130; 230; 330) to support the loading portion (30; 130; 230; 330); and a coupling portion (50; 150; 250) comprising a return element (51), wherein the return element (51) generates a return force for returning the coupling portion (50; 150; 250) to its original length when the coupling portion (50; 150; 250) is stretched, wherein the coupling portion (50; 150; 250) couples the base portion (40) and the loading portion (30; 130; 230; 330) via the return element (51) arranged between the base portion (40) and the loading portion (30; 130; 230; 330), the loading section (30; 130; 230; 330) and the base section (40) are arranged such that a lower part of the loading section (30; 130; 230; 330) and an upper part of the base section (40) face each other, and one of the upper part of the base section (40) and the lower part of the loading section (30; 130; 230; 330) comprises a spherical surface that is convex downwards, and the other of the upper part of the base section (40) and the lower part of the loading section (30; 130; 230; 330) comprises a guide section (42), wherein the guide section (42) guides the base section (40) and the loading section (30; 130; 230; 330) such that the base section (40) and the loading section (30; 130; 230; 330) are movable relative to each other in a direction along the spherical surface, characterized by a rotational position changing mechanism (60) that causes the loading section (30; 130; 230; 330), the base section (40) and the coupling section (50 150; 250) to rotate integrally relative to a main body (22) of the mobile object (20) about a rotation axis extending in a first direction in which the base section (40) and the loading section (30; 130; 230; 330) are arranged. [2] The position control device according to claim 1, comprising a coupling position changing mechanism (70; 270) configured to change a coupling position at which the coupling portion (50; 250) is coupled to the base portion (40) and / or a coupling position at which the coupling portion (50; 250) is coupled to the loading portion (30; 230). [3] Position control device according to claim 1, further comprising: a determination unit for determining information about a movement state of the mobile object (20); a relative position changing mechanism (80) which, when a direction in which the base portion (40) and the loading portion (130) are arranged is defined as a first direction, is provided to form a middle part of the coupling portion (150) in the first direction, and is configured to separate a part closer to the base portion (40) and a part closer to the loading portion (130) from each other in a second direction intersecting the first direction; a drive unit (84, 88) coupled to the relative position changing mechanism (80) and configured to actuate the relative position changing mechanism (80); and a control unit (90) for controlling an operation of the drive unit (84, 88) based on the information determined by the determination unit. [4] Position control device according to one of claims 1 to 3, wherein the mobile object (20) is a vehicle, and the loading platform (21; 121) is a seat.

Images