Caster assembly and robot provided with same

Abstract

Disclosed are a caster assembly and a robot provided with same. The caster assembly is provided with an outer spring and an inner spring, and can change the value of a spring constant applied to a caster. The caster assembly according to an embodiment of the present invention comprises a motor unit, a moving member, an outer member, a shaft member, the outer spring, the inner spring, and the caster. When the moving member moves toward the inner spring, the inner spring is compressed and contracted in the longitudinal direction. Also, when the moving member moves toward the motor unit, the length of the inner spring is restored to the original length thereof.

Description

Caster assembly and robot equipped with it

[0001] The present invention relates to a caster assembly and a robot equipped with the same.

[0002] The robot (2) illustrated in Fig. 1 is a robot that delivers food. A caster assembly (1) for moving the robot (2) is mounted on the lower part of the robot (2).

[0003] Conventional food delivery robots use caster assemblies equipped with springs with very low spring constant values ​​to prevent food (e.g., soup) from overflowing during delivery.

[0004] In general, when a food delivery robot runs on a sloped or stepped surface, there is a problem of beverages or food on the tray spilling, so the spring constant value of the spring equipped in the caster assembly is set very low and the moving speed of the robot is set slow.

[0005] If the spring constant is set too low, the robot will sway violently back and forth when accelerating or decelerating rapidly, or when it suddenly stops after moving at high speed, causing food on the tray to spill. Consequently, conventional food delivery robots are often unable to move at high speeds.

[0006] Therefore, when the robot is driving on a curved, inclined, or stepped surface with food on the robot, it is necessary to lower the spring constant value of the spring provided in the caster assembly to prevent the food from spilling.

[0007] And, when the robot is moving on a flat surface while there is food on the robot, it is necessary to increase the spring constant value of the spring provided in the caster assembly to enable the robot to move at a high speed while preventing the food from spilling.

[0008] Additionally, when the robot is moving without food, it is necessary to increase the spring constant value of the spring provided in the caster assembly so that the robot can move quickly without shaking.

[0009] The purpose of the present invention is to provide a caster assembly and a robot equipped with the same, which can improve the problem of objects falling or food spilling when a robot equipped with the caster assembly delivers objects or food, for example, by changing the value of the spring constant of the spring equipped in the caster assembly according to the state of the ground.

[0010] The above-described object of the present invention is achieved by the specific contents described below.

[0011] A caster assembly according to an embodiment of the present invention includes a motor unit, a movable member, an outer member, a shaft member, an outer spring, an inner spring, and a caster. The movable member is moved by the motor unit. The outer member is arranged so that the movable member can rotate and move. The shaft member is arranged in an inner space of the outer member and is movable. The outer spring is arranged between the outer member and the shaft member and is supported by the shaft member. The inner spring is arranged between the movable member and the shaft member, is supported by the shaft member, and is arranged in a through hole of the outer spring. The caster is connected to the shaft member. When the movable member moves toward the inner spring, the inner spring is compressed and contracted in the longitudinal direction. When the movable member moves toward the motor unit, the length of the inner spring is restored to its original length.

[0012] Specifically, the movable member includes an extension, a lower groove, and a movable member hole. The extension is formed on one side, and the lower groove is formed on the other side. The movable member hole is a hole connecting the one side and the lower groove. In addition, the rotating member of the motor unit is inserted into the movable member hole. When the rotating member rotates, the movable member rotates and moves toward the inner spring or toward the motor unit.

[0013] Specifically, when the movable member moves toward the inner spring, the extension of the movable member comes into contact with one side of the outer member, so that the movable member is restricted from moving.

[0014] Specifically, when the movable member moves toward the inner spring, one side of the inner spring comes into contact with the bottom surface of the lower groove of the movable member.

[0015] Specifically, the rotating member of the motor unit is formed to include a die-cut shape, and the moving member hole of the moving member is formed in a D shape corresponding to the die-cut shape of the rotating member.

[0016] Specifically, when the movable member moves toward the motor unit, the bottom surface of the upper groove formed on one side of the movable member or the one side comes into contact with the end of the cut shape formed on the rotating member of the motor unit, so that the movable member is restricted from moving.

[0017] Specifically, the movable member includes screw threads formed on the outer surface between one side and the other side. In addition, the outer member includes an outer upper hole in which the movable member is positioned so as to be rotatable and movable. A screw groove is formed on the inner surface of one side of the outer member surrounding the outer upper hole. The screw threads of the movable member engage with the screw grooves of the outer member.

[0018] Specifically, when the movable member is coupled with the outer upper hole of the outer member, the extension of the movable member is disposed on the outside of the outer member, and the screw thread of the movable member is disposed in the outer upper hole.

[0019] Specifically, the shaft member includes a groove formed on one side and a groove formed on the other side. A portion of an outer spring and a portion of an inner spring are disposed in the groove on the one side. A supporting shaft portion of the caster is disposed in the groove on the other side.

[0020] Specifically, the shaft member includes a stepped surface formed on an outer surface. With the stepped surface as a boundary, a cross-sectional diameter of one side of the shaft member is formed to be wider than a cross-sectional diameter of the other side.

[0021] A caster assembly according to an embodiment of the present invention includes a holder member. The holder member is positioned below a shaft member, and a holder hole is formed in the middle thereof. A cross-sectional diameter of one side of the shaft member is formed to be wider than the diameter of the holder hole, and a cross-sectional diameter of the other side of the shaft member is formed to be narrower than the diameter of the holder hole.

[0022] Specifically, the support shaft portion of the caster is inserted into the other side groove of the shaft member through the holder hole of the holder member and fixed therein.

[0023] Specifically, one side of the outer spring contacts the inner surface of one side of the outer member, and the other side of the outer spring contacts the bottom surface of one side of the groove of the shaft member.

[0024] Specifically, the inner spring is fixed to one side groove of the shaft member.

[0025] Specifically, a caster assembly according to an embodiment of the present invention includes a bush member. The bush member is arranged in the inner space of an outer member. An outer spring, an inner spring, and a shaft member are arranged in the inner space of the bush member.

[0026] Specifically, a caster assembly according to an embodiment of the present invention includes a control unit. The control unit controls a motor of the motor unit. The control unit controls the direction and rotational speed of the motor, thereby controlling the direction and distance of movement of the movable member.

[0027] A caster assembly according to an example of the embodiment of the present invention described above is provided in a robot.

[0028] A caster assembly according to an example of an embodiment of the present invention and a robot equipped with the same have an outer spring and an inner spring, and change the value of the spring constant of the inner spring depending on the state of the ground, so that when a robot equipped with the caster assembly delivers, for example, an object or food, it has the effect of preventing the object from falling or the food from spilling.

[0029] More detailed effects of the caster assembly of the present invention and the robot equipped with the same are described in the form for implementing the invention below.

[0030] Figure 1 shows an example of one embodiment of a robot to which the caster assembly of the present invention can be mounted.

[0031] Figure 2 shows a caster assembly mounted on the robot of Figure 1.

[0032] Figure 3 shows a caster assembly according to an example of an embodiment of the present invention.

[0033] Figure 4 is a cross-sectional view taken along line IV-IV of Figure 3.

[0034] Figure 5 is an exploded perspective view of Figure 3.

[0035] Figure 6 shows the process of moving the moving member and the shape change of the inner spring.

[0036] Figure 7 shows the bracket of Figure 5.

[0037] Fig. 8 shows the caster housing of Fig. 5.

[0038] Fig. 9 shows the moving member of Fig. 5.

[0039] Figure 10 shows the outer member of Figure 5.

[0040] Fig. 11 shows the bushing member of Fig. 5.

[0041] Figure 12 shows a spring fixing part and a fixing member.

[0042] Fig. 13 shows the shaft member of Fig. 5.

[0043] Fig. 14 shows the holder member of Fig. 5.

[0044] Fig. 15 shows the washer member of Fig. 5.

[0045] Figure 16 is a block diagram showing a control unit.

[0046] Hereinafter, examples of embodiments of the present invention will be described in more detail with reference to the attached drawings. For components of the present invention that are clearly understandable and easily reproducible by those skilled in the art using conventional techniques, a detailed description thereof will be omitted so as not to obscure the gist of the present invention.

[0047] The attached drawings are only provided to facilitate understanding of examples of embodiments disclosed in this specification, and the technical ideas disclosed in this specification are not limited by the attached drawings.

[0048] Singular expressions include plural expressions unless the context clearly indicates otherwise.

[0049] Additionally, terms including ordinal numbers, such as "first" and "second," used herein may be used to describe various components, but these components should not be limited by these terms. These terms are used solely to distinguish one component from another. For example, without departing from the scope of the present invention, a first component could be referred to as a "second component," and similarly, a second component could also be referred to as a "first component."

[0050] Hereinafter, a caster assembly and a robot having the same according to an exemplary embodiment of the present invention will be described. Fig. 1 illustrates a food delivery robot as an exemplary embodiment of a robot to which the caster assembly of the present invention can be mounted, and Fig. 2 illustrates the caster assembly of Fig. 1. In addition, Fig. 3 illustrates a caster assembly according to an exemplary embodiment of the present invention.

[0051] Hereinafter, a caster assembly according to an example of an embodiment of the present invention and a robot equipped with the same may be briefly referred to as a 'caster assembly of the present invention'.

[0052] Referring to FIGS. 3 to 6, the caster assembly (1) of the present invention includes a motor portion (10), a bracket portion (20), a caster housing (30), a moving member (40), an outer member (50), a bush member (60), an outer spring (61), an inner spring (62), a spring fixing member (63), a shaft member (70), a holder member (80), a washer member (94), and a caster (90).

[0053] The motor unit (10) is connected to a moving member (40) described later and moves the moving member (40).

[0054] The motor section (10) includes a motor case (11), a motor (12), a rotating member (13), and a connecting member (not shown).

[0055] The motor case (11) forms the exterior of the motor section (10).

[0056] The motor case (11) has an internal accommodation space, and a motor (12), a rotating member (13), and a connecting member are arranged in the accommodation space.

[0057] Motor (12) represents a commonly used motor.

[0058] The rotating member (13) is a rotating member and is connected to the moving member (40).

[0059] The rotating member (13) is formed in a rod shape with a preset length.

[0060] One side of the rotating member (13) is connected to the moving member (40), and the other side of the rotating member (13) is connected to the connecting member. The one side and the other side refer to opposite sides in the longitudinal direction of the rotating member (13).

[0061] The rotating member (13) is inserted into the moving member hole (45) of the moving member (40).

[0062] When the rotating member (13) rotates, the movable member (40) moves while rotating.

[0063] The rotating member (13) may be formed to include a D-CUT type. In other words, the rotating member (13) may be formed to have a shape in which a portion of the outer circumferential surface is cut off in the longitudinal direction of the rotating member (13).

[0064] The cut shape is formed with a preset length from one side of the rotating member (13) to the other side. One side of the rotating member (13) is arranged to face the moving member.

[0065] The connecting member is connected to the rotation shaft of the motor (12) and the rotation member (13).

[0066] Specifically, one side of the connecting member is connected to the rotational axis of the motor (12), and the other side of the connecting member is connected to the other side of the rotating member (13).

[0067] A connecting member may be formed by combining multiple components.

[0068] For example, the connecting member may be a chain or belt, or may be a gear assembly comprising a plurality of gears meshed with each other.

[0069] According to another embodiment, the motor (12) of the motor unit (10) may be connected to the moving member (40) without the aforementioned connecting member. At this time, the rotational axis of the motor (12) may be connected to the aforementioned rotating member (13), or the rotational axis of the motor (12) may play a role corresponding to the rotating member (13).

[0070] The bracket part (20) is connected to the motor part (10).

[0071] Specifically, the bracket portion (20) can be connected to the motor case (11) and / or the rotating member (13) of the motor portion (10).

[0072] The bracket part (20) accommodates a movable member (40), an outer member (50), a bush member (60), an outer spring (61), an inner spring (62), and a shaft member (70).

[0073] Referring to Figure 7, Figure 7 (a) is a top perspective view, and Figure 7 (b) is a bottom perspective view.

[0074] The bracket part (20) is formed in a cylindrical shape with a preset length in one direction and has an accommodation space (internal space) (24) therein.

[0075] The bracket portion (20) includes one side (21) and the other side (22). The one side (21) and the other side (22) face opposite sides in the longitudinal direction of the bracket portion (20). For example, the one side (21) and the other side (22) may be an upper side and a lower side. The longitudinal direction of the bracket portion (20) refers to a direction orthogonal to the one side (21) of the bracket portion (20).

[0076] A bracket upper hole (211) and a bracket fastening hole (212) are formed on one side (21) of the bracket portion (20).

[0077] The bracket upper hole (211) and the bracket fastening hole (212) are holes that penetrate one side (21) of the bracket part (20) and are connected to the internal space (24) of the bracket part (20).

[0078] The rotating member (13) of the motor unit (10) is placed in the upper hole (211) of the bracket.

[0079] A fastening member (p) (e.g., a bolt or screw) that connects the motor case (11) and the bracket part (20) is placed in the bracket fastening hole (212).

[0080] A plurality of bracket fastening holes (212) are formed.

[0081] A plurality of bracket fastening holes (212) are arranged at a preset distance from the bracket upper hole (211) along the radial direction of one side (21) of the bracket portion (20) and at a preset distance along the circumferential direction of the bracket upper hole (211).

[0082] A bracket lower hole (221) is formed on the other side (22) of the bracket portion (20).

[0083] The bracket lower hole (221) is a hole that penetrates the other side (22) of the bracket part (20) and communicates with the internal space (24) of the bracket part (20).

[0084] Alternatively, the other side (22) of the bracket portion (20) may be formed entirely as a hole (bracket lower hole (221)) without any portion forming a surface. That is, the other side (22) of the bracket portion (20) may be entirely open.

[0085] The bracket part (20) includes a fastening part (222).

[0086] The fastening portion (222) is formed on the other side (22) of the bracket portion (20).

[0087] The fastening member (222) is positioned by inserting a fastening member (p) (e.g., a bolt or screw) that connects the bracket member (20) and the caster housing (30) described later.

[0088] The fastening portion (222) is formed on the outer surface (or outer circumference) (23). The outer surface (or outer circumference) (23) represents the outer side connecting one side (21) and the other side (22) of the bracket portion (20).

[0089] The fastening part (222) includes a fastening body (2221) and a fastening groove (2222).

[0090] The fastening body (2221) is formed by protruding radially outward from the outer surface (23) of the bracket portion (20) to the other side (22).

[0091] A plurality of fastening bodies (2221) can be formed.

[0092] A plurality of fastening bodies (2221) are arranged at a preset distance along the circumferential direction of the bracket portion (20).

[0093] One of the plurality of fastening bodies (2221) may be formed to protrude further radially outward from the outer surface (23) of the bracket portion (20) to the other side surface (22), unlike the other fastening bodies (2221). The length by which the fastening body (2221) protrudes radially from the outer surface (23) is determined according to the arrangement position of the fastening member (p).

[0094] A fastening groove (2222) is formed in the fastening body (2221).

[0095] The fastening groove (2222) is formed in the longitudinal direction of the bracket portion (20). And the fastening groove (2222) is formed by being sunken from the other side (22) of the bracket portion (20) toward one side (21) to a preset depth.

[0096] According to an embodiment, the fastening groove (2222) may be formed not only in a groove shape but also in a through hole shape penetrating the fastening body (2221).

[0097] A fastening member (p) connecting the bracket part (20) and the caster housing (30) is inserted and placed in the fastening groove (2222).

[0098] The outer surface (23) of the bracket portion (20) may be formed with one or more grooves, holes communicating with the internal space, steps, etc. According to an embodiment, the grooves, holes, steps, etc. may be formed by connecting the outer surface (23) and the upper surface (21) of the bracket portion (20).

[0099] The bracket part (20) is connected to the caster housing (30). One side (21) of the bracket part (20) is connected to the motor part (10), and the other side (22) of the bracket part (20) is connected to the caster housing (30).

[0100] Referring to Figure 8, Figure 8 (a) is a top perspective view, and Figure 8 (b) is a bottom perspective view.

[0101] The caster housing (30) is connected to the bracket portion (20), the outer member (50) described below, and / or the holder member (80).

[0102] The caster housing (30) accommodates a caster (90) described later and protects the caster (90) from colliding with an external object. The wheel (92) of the caster (90) protrudes outward from the caster housing (30) and comes into contact with the ground (floor surface).

[0103] The caster housing (30) can be formed into a cylindrical shape with a preset length in one direction. In addition, the caster housing (30) has an accommodation space (internal space) (34) therein. A portion of the caster (90) is placed in the accommodation space (34).

[0104] According to an embodiment, the caster housing (30) may be formed such that the cross-sectional diameter of the internal space (34) increases in one direction (e.g., downward). The cross-sectional diameter represents the diameter of the cross-section when the internal space (34) is cut in a direction orthogonal to the one direction.

[0105] The caster housing (30) includes one side (31) and the other side (32). The one side (31) and the other side (32) face opposite sides in the longitudinal direction of the caster housing (30). For example, the one side (31) and the other side (32) may be an upper side and a lower side. The longitudinal direction of the caster housing (30) refers to a direction orthogonal to the one side (31) of the caster housing (30).

[0106] A housing upper hole (311) and a housing fastening hole (312) are formed on one side (31) of the caster housing (30).

[0107] The housing upper hole (311) and the housing fastening hole (312) are holes that penetrate one side (31) of the caster housing (30) and communicate with the internal space (34) of the caster housing (30).

[0108] In the upper hole of the housing (311), an outer member (50), a bush member (60), a shaft member (70), and a support shaft part (93) of a caster (90) are arranged.

[0109] A plurality of housing fastening holes (312) are formed.

[0110] A fastening member (p) connecting the bracket portion (20) and the caster housing (30), and a fastening member (p) connecting the outer member (50) and / or the holder member (80) and the caster housing (30) are arranged in the housing fastening hole (312). The fastening member (p) represents, for example, a bolt or a screw.

[0111] A plurality of housing fastening holes (312) are arranged at a preset distance from the housing upper hole (311) along the radial direction of one side (31) of the caster housing (30) and at a preset distance along the circumferential direction of the housing upper hole (311).

[0112] A housing lower hole (321) is formed on the other side (32) of the caster housing (30).

[0113] The housing lower hole (321) is a hole that penetrates the other side (32) of the caster housing (30) and communicates with the internal space (34) of the caster housing (30).

[0114] Alternatively, the other side (32) of the caster housing (30) may be formed entirely as a hole (housing lower hole (321)) without any portion forming a surface. That is, the other side (32) of the caster housing (30) may be entirely open.

[0115] A part of the wheel (92) of the caster (90) is positioned to protrude outwardly by penetrating the housing lower hole (321), and the wheel (92) protruding outwardly comes into contact with the ground (floor surface).

[0116] Referring to Figure 9, (a) of Figure 9 is a front view, (b) is a top perspective view, and (c) is a bottom perspective view.

[0117] The moving member (40) is connected to the rotating member (13) of the motor unit (10).

[0118] The movable member (40) rotates together with the rotating member (13).

[0119] The moving member (40) is formed in a rod shape with a preset length in one direction.

[0120] The movable member (40) includes one side (41) and the other side (42). The one side (41) and the other side (42) face opposite sides in the longitudinal direction of the movable member (40). For example, the one side (41) and the other side (42) may be an upper surface and a lower surface. The longitudinal direction of the movable member (40) refers to a direction orthogonal to the one side (41) of the movable member (40).

[0121] According to an embodiment, an upper groove (411) may be formed on one side (41) of the movable member (40).

[0122] The upper groove (411) is formed by recessing from one side (41) of the movable member (40) toward the other side (42) to a preset depth.

[0123] The moving member (40) includes an extension (412).

[0124] The extension (412) is formed on one side (41).

[0125] The extension (412) is formed by extending from the edge of one side (41) of the movable member (40) to a preset length in the radial direction outside of the one side (41).

[0126] The extension (412) is formed along the circumferential direction at the edge of one side (41) of the movable member (40), and is thus formed in a ring shape.

[0127] Due to the extension (412), the diameter of one side (one side (41) side) of the movable member (40) is formed to be larger than the diameter of the other side (the other side (42) side) of the movable member (40).

[0128] The diameter of one side of the moving member (40) is the diameter of one side (41) plus the extension length of the extension part (412).

[0129] In addition, due to the extension (412), the outer surface (or outer circumference) (43) of the movable member (40) is formed in a stepped manner. That is, a stepped surface (431) is formed on the outer surface (or outer circumference) (43) of the movable member (40). The outer surface (or outer circumference) (43) represents an external side connecting one side (41) and the other side (42) of the movable member (40), and the stepped surface (431) represents a surface formed in a direction orthogonal to the outer surface (or outer circumference) (43).

[0130] A screw thread (432) is formed on the outer surface (or outer circumference) of the moving member (40).

[0131] The screw thread (432) is formed from the bottom of the step surface (431) to the other side surface (42).

[0132] The screw thread (432) is combined with the screw groove (513) formed in the outer member (50) described later.

[0133] Since the screw thread (432) of the movable member (40) is coupled with the screw groove (513) of the outer member (50), the movable member (40) is connected to the outer member (50).

[0134] When the movable member (40) rotates, the screw thread (432) of the movable member (40) moves along the screw groove (513) of the outer member (50), so that the movable member (40) moves in one direction or in the opposite direction (e.g., upward or downward).

[0135] A lower groove (421) is formed on the other side (42) of the moving member (40).

[0136] The lower groove (421) is formed by recessing from the other side (42) of the movable member (40) toward one side (41) to a preset depth.

[0137] An inner spring (62) described later can be placed in the lower groove (421).

[0138] In detail, as the movable member (40) moves, one side of the inner spring (62) can be placed in the lower groove (421) and can come into contact with the bottom surface (4211) of the lower groove (421).

[0139] The moving member (40) includes a moving member hole (45).

[0140] The moving member hole (45) is a through hole connecting one side (41) and the lower groove (421), and is in communication with the lower groove (421).

[0141] In an embodiment in which an upper groove (411) is formed, the movable member hole (45) is a through hole connecting the upper groove (411) and the lower groove (421), and is in communication with the upper groove (411) and the lower groove (421), respectively.

[0142] The rotating member (13) of the motor unit (10) is inserted and placed in the moving member hole (45).

[0143] The moving member hole (45) can be formed in a shape corresponding to the shape of the rotating member (13) of the motor unit (10).

[0144] That is, the movable member hole (45) can be formed in a D shape when viewed from above. Accordingly, when one side (D-CUT type) of the rotating member (13) is inserted into the movable member hole (45) and rotates, the movable member (40) also rotates.

[0145] However, a certain gap (gap) is formed between the inner surface of the movable member hole (45) and the outer surface of the rotating member (13). Due to this, the movable member (40) can move smoothly. This is because if the bonding force between the rotating member (13) and the movable member hole (45) is strong, the movable member (40) can rotate smoothly, but cannot move smoothly.

[0146] Referring to Figure 10, Figure 10 (a) is a top perspective view, and Figure 10 (b) is a bottom perspective view.

[0147] The outer member (50) is combined with the moving member (40) and the caster housing (30).

[0148] Specifically, one side of the outer member (50) is coupled with the movable member (40), and the other side of the outer member (50) is coupled with the caster housing (30). The movable member (40) is rotatably coupled with one side of the outer member (50).

[0149] The outer member (50) accommodates a part of the moving member (40), a bush member (60), an outer spring (61), an inner spring (62), and a shaft member (70).

[0150] The outer member (50) is formed in a cylindrical shape with a preset length in one direction and has an accommodation space (internal space) (54) inside.

[0151] The outer member (50) includes one side (51) and the other side (52). The one side (51) and the other side (52) face opposite sides in the longitudinal direction of the outer member (50). For example, the one side (51) and the other side (52) may be an upper side and a lower side. The longitudinal direction of the outer member (50) refers to a direction orthogonal to the one side (51) of the outer member (50).

[0152] An outer upper hole (511) is formed on one side (51) of the outer member (50).

[0153] The outer upper hole (511) is a hole that penetrates one side (51) of the outer member (50) and communicates with the internal space (54) of the outer member (50).

[0154] A movable member (40) is placed in the outer upper hole (511). The movable member (40) is capable of rotating and moving while placed in the outer upper hole (511).

[0155] When the movable member (40) is combined with the outer upper hole (511), the extension (412) of the movable member (40) is placed on the outside of the outer member (50), and the screw thread (432) of the movable member (40) is placed in the outer upper hole (511).

[0156] A screw groove (513) is formed on the inner surface (or inner circumference) (512) of one side (51) of the outer member (50) surrounding the outer upper hole (511). The screw groove (513) is coupled with the screw thread (432) of the moving member (40).

[0157] Since the screw thread (432) of the movable member (40) can move along the screw groove (513) of the outer member (50), the movable member (40) can move in one direction or in the opposite direction (for example, upward or downward) while being placed in the outer upper hole (511).

[0158] For example, when the movable member (40) rotates in one rotational direction, the movable member (40) moves in one direction (e.g., downward).

[0159] If the movable member (40) continues to move in one direction, the extension (412) of the movable member (40) comes into contact with one side (51) of the outer member (50), so that the movable member (40) is restricted from moving in one direction any further.

[0160] Specifically, when the movable member (40) completes rotation in one rotational direction, the extension (412) of the movable member (40) is disposed outside the outer member (50), and the screw thread (432) of the movable member (40) is disposed in the outer upper hole (511) and the inner space (54) of the outer member (50). At this time, the step surface (431) formed on the outer surface (or outer peripheral surface) (43) of the movable member (40) comes into contact with one side surface (51) of the outer member (50), so that the movable member (40) is restricted from moving in one direction (for example, downward) any longer. And at this time, the movable member (13) of the motor unit (10) stops rotating.

[0161] When the moving member (40) can no longer move in one direction and a force greater than a certain torque is applied to the rotation axis of the motor (12), the motor (12) is controlled to stop driving.

[0162] And, when the movable member (40) rotates in the opposite direction of the one rotational direction, the movable member (40) moves in the opposite direction of the one direction (for example, upward direction).

[0163] If the moving member (40) continues to move in the opposite direction of one direction, one side (41) of the moving member (40) or the bottom surface (4111) of the upper groove (411) comes into contact with the end of the cut shape formed in the rotating member (13) of the motor unit (10), so that the moving member (40) is restricted from moving in the opposite direction of one direction any longer.

[0164] Specifically, when the movable member (40) completes rotation in the opposite direction of one rotational direction, the other side (the other side (52) side) of the movable member (40) is placed in the outer upper hole (511), and the remainder of the movable member (40) is placed on the outside of the outer member (50). At this time, one side (41) of the movable member (40) or the bottom surface (4111) of the upper groove (411) comes into contact with the end of the die-cut shape formed in the movable member (13) of the motor unit (10), so that the movable member (40) is restricted from moving in the opposite direction (for example, upward) of one direction any longer. And at this time, the movable member (13) of the motor unit (10) stops rotating.

[0165] When a force greater than a certain torque is applied to the rotation axis of the motor (12) so that the moving member (40) can no longer move in the opposite direction of one direction, the motor (12) is controlled to stop driving.

[0166] An outer lower hole (521) is formed on the other side (52) of the outer member (50).

[0167] The outer lower hole (521) is a hole that penetrates the other side (52) of the outer member (50) and communicates with the internal space (54) of the outer member (50).

[0168] Alternatively, the other side (52) of the outer member (50) may be formed entirely as a hole (outer lower hole (521)) without any portion forming a surface. That is, the other side (52) of the outer member (50) may be entirely open.

[0169] The outer member (50) includes an outer fastening member (522).

[0170] The outer fastening portion (522) is formed on the other side (52) of the outer member (50).

[0171] The outer fastening member (522) is arranged by inserting a fastening member (p) that connects the outer member (50) and the caster housing (30), and a fastening member (p) that connects the outer member (50) and the holder member (80). The fastening member (p) represents, for example, a bolt or a screw.

[0172] The outer fastening portion (522) is formed on the outer surface (or outer circumference) (53). The outer surface (or outer circumference) (53) represents the outer side connecting one side (51) and the other side (52) of the outer member (50).

[0173] The outer fastening part (522) includes an outer fastening body (5221) and an outer fastening hole (5222).

[0174] The outer fastening body (5221) is formed by protruding radially outward from the outer surface (53) of the outer member (50) to the other side (52).

[0175] According to an embodiment, the outer surface of the outer fastening body (5221) may be formed with one or more grooves (referred to as 'outer grooves (5223)').

[0176] Specifically, the outer home (5223) is formed by being sunken from the outer surface of the outer fastening body (5221) toward the outer lower hole (521) to a preset depth.

[0177] When a plurality of outer homes (5223) are formed, the adjacent outer homes (5223) are spaced apart by a preset distance, and the preset distance may be different for each outer home (5223).

[0178] In the outer home (5223), a fastening member (p) that connects the bracket portion (20) and the caster housing (30) is arranged. Accordingly, the outer fastening body (5221) does not interfere with the fastening member (p).

[0179] According to another embodiment (not shown), the outer fastening body (5221) may be formed entirely or partially along the circumferential direction of the outer surface (53) of the outer member (50).

[0180] When the outer fastening body (5221) is partially formed along the circumferential direction of the outer surface (53) of the outer member (50), a plurality of outer fastening bodies (5221) are formed.

[0181] A plurality of outer fastening bodies (5221) are arranged at a preset distance along the circumference of the outer member (50). The preset distance may vary between adjacent outer fastening bodies (5221).

[0182] A plurality of outer fastening holes (5222) are formed in the outer fastening body (5221).

[0183] The outer fastening hole (5222) is a hole that penetrates the outer fastening body (5221) and is formed in the longitudinal direction of the outer member (50).

[0184] A fastening member (p) connecting the outer member (50) and the caster housing (30) and a fastening member (p) connecting the outer member (50) and the holder member (80) are inserted and placed in the outer fastening hole (5222).

[0185] As shown in the drawing, when the outer member (50) and the caster housing (30) are combined, one side (51) and the outer side (53) of the outer member (50) are placed on the outside of the caster housing (30), and the outer fastening portion (522) of the outer member (50) is placed in the internal space (34) of the caster housing (30).

[0186] This arrangement structure is achieved by having one side (51) and an outer side (53) of the outer member (50) pass through the upper housing hole (311) of the caster housing (30) and come out of the caster housing (30), and the outer fastening portion (522) of the outer member (50) does not pass through the upper housing hole (311) and remains in the internal space (34) of the caster housing (30).

[0187] In this state, the fastening member (p) is inserted and placed into the outer fastening hole (5222) formed in the outer fastening body (5221) and the housing fastening hole (312) formed on one side (31) of the caster housing (30).

[0188] Although not shown, according to another embodiment, the entire outer member (50) may be disposed outside the caster housing (30). That is, the outer fastening portion (522) of the outer member (50) may be disposed on one side (31) of the caster housing (30). At this time, the outer lower hole (521) of the outer member (50) communicates with the housing upper hole (311) of the caster housing (30). In this state, the fastening member (p) may be disposed by being inserted into the housing fastening hole (312) formed on one side (31) of the caster housing (30) and the outer fastening hole (5222) formed in the outer fastening body (5221).

[0189] Referring to Figure 11, Figure 11 (a) is a top perspective view, and Figure 11 (b) is a cross-sectional view.

[0190] The bush member (60) is placed in the inner space of the outer member (50).

[0191] The bush member (60) facilitates the movement of the shaft member (70) described later.

[0192] The bush member (60) is formed into a cylindrical shape with a preset length in one direction. In addition, the bush member (60) has a through hole extending through the middle in the longitudinal direction (in one direction). The longitudinal direction of the bush member (60) refers to a direction orthogonal to the width of the bush member (60).

[0193] The through hole of the bush member (60) can be divided into a bush upper hole (601), a bush lower hole (602), and a receiving space (internal space) (603).

[0194] In detail, the bush upper hole (601) is formed on one side of the bush member (60) and is a hole penetrating the one side. The bush lower hole (602) is formed on the other side of the bush member (60) and is a hole penetrating the other side. The internal space (603) is connected to the bush upper hole (601) and the bush lower hole (602).

[0195] An outer spring (61), an inner spring (62), and a shaft member (70) are arranged (or accommodated) in the inner space (603) of the bush member (60).

[0196] Referring to FIGS. 5 and 6, the outer spring (61) is placed in the inner space (603) of the bush member (60).

[0197] The outer spring (61) is an elastic body that is elastically deformed by an external force and has a restoring force when its shape is deformed.

[0198] The outer spring (61) is a type of coil spring.

[0199] The outer spring (61) alleviates the shock received by the caster (90) as it moves. As a result, the shock and shaking received by structures (e.g., components constituting a robot) placed on the caster (90) and objects (e.g., food) placed on the structures are alleviated.

[0200] The outer spring (61) includes one side and the other side in the longitudinal direction. The one side and the other side face opposite sides.

[0201] The outer spring (61) has a through hole (611) penetrating the center of one side and the other side.

[0202] A part of the movable member (40) and an inner spring (62) described later are arranged in the through hole (611) of the outer spring (61). In detail, when the movable member (40) moves toward the caster (90), a part of the movable member (40) (specifically, the other side (42)) enters the through hole (611) of the outer spring (61).

[0203] One side of the outer spring (61) is supported by the outer member (50). Specifically, one side of the outer spring (61) is in contact with the inner surface of one side (upper surface) (51) of the outer member (50).

[0204] The other side of the outer spring (61) is supported by a shaft member (70) described later. Specifically, the other side of the outer spring (61) is inserted into a groove (711) on one side of the shaft member (70) and comes into contact with the bottom surface of the groove (711) on one side.

[0205] Depending on the embodiment, one side of the outer spring (61) may or may not be fixed to the outer member (50). And, the other side of the outer spring (61) may or may not be fixed to the shaft member (70).

[0206] If one side and / or the other side of the outer spring (61) is fixed, the caster assembly (1) of the present invention includes a component that fixes one side and / or the other side of the outer spring (61).

[0207] Referring to FIGS. 5 and 6, the inner spring (62) is placed inside the outer spring (61). Specifically, the inner spring (62) is placed in the through hole (611) of the outer spring (61).

[0208] Since the width of the inner spring (62) is smaller than the width of the outer spring (61), the inner spring (62) can be placed in the through hole (611) of the outer spring (61).

[0209] The inner spring (62) is an elastic body that is elastically deformed by an external force and has a restoring force when its shape is deformed.

[0210] The inner spring (62) is a type of coil spring.

[0211] The inner spring (62) alleviates the shock received by the caster (90) as it moves. As a result, the shock and shaking received by the structure (e.g., components constituting the robot) placed on the caster (90) and the object (e.g., food) placed on the structure are alleviated.

[0212] The inner spring (62) includes one side and the other side in the longitudinal direction and has a through hole (621) penetrating the center of the one side and the other side. The one side and the other side face opposite sides.

[0213] One side of the inner spring (62) can be supported by the movable member (40). Specifically, one side of the inner spring (62) can come into contact with the bottom surface (4211) of the lower groove (421) of the movable member (40).

[0214] The other side of the inner spring (62) is supported by a shaft member (70) described later. Specifically, the other side of the inner spring (62) is supported and fixed to a groove (711) on one side of the shaft member (70) by a spring fixing portion (63) and a fixing member (64).

[0215] Figure 6 (a) shows the state before the movable member (40) moves downward, and (b) shows the state after the movable member (40) moves downward.

[0216] When the movable member (40) rotates in one rotational direction and moves toward the inner spring (62), one side of the inner spring (62) enters the lower groove (421) of the movable member (40) and comes into contact with the bottom surface (4211) of the lower groove (421).

[0217] And, as the moving member (40) continues to move toward the inner spring (62), the inner spring (62) is compressed and contracted in the longitudinal direction, and the value of the spring constant of the inner spring (62) increases.

[0218] In the above-described state, when the moving member (40) rotates in the opposite direction of the rotational direction and moves toward the motor unit (10), the length of the inner spring (62) is restored to its original length, and the value of the spring constant of the inner spring (62) gradually decreases to its original value.

[0219] And, when the moving member (40) completes moving toward the motor unit (10), one side of the inner spring (62) is separated from the bottom surface (4211) of the lower groove (421) of the moving member (40) and is positioned in the lower groove (421) or below the lower groove (421).

[0220] In the present invention, the value of the spring constant of the inner spring (62) is higher than the value of the spring constant of the outer spring (61).

[0221] Meanwhile, the value of the spring constant of the inner spring (62) can be changed.

[0222] The caster assembly (1) of the present invention may include a control unit (100) (see FIG. 16).

[0223] The control unit (100) can control the motor unit (10) (specifically, the motor (12)).

[0224] The control unit (100) is electrically connected to the motor unit (10) (specifically, the motor (12)).

[0225] The control unit (100) can control the direction of rotation and the rotation speed of the motor (12) to adjust (control) the direction of movement and the distance of movement of the moving member (40).

[0226] As the control unit (100) controls the motor (12), the inner spring (62) can be contracted in the longitudinal direction or restored to its original length. That is, the value of the spring constant of the inner spring (62) can be changed by the control unit (100).

[0227] In addition, the control unit (100) can control the rotational direction and rotational speed of the motor (12) in preset steps. Accordingly, the value of the spring constant of the caster assembly (1) of the present invention can be determined in steps.

[0228] In addition, the robot (2) having the caster assembly (1) of the present invention may include a sensor (e.g., a camera sensor) that detects the state of the ground on which the caster (90) (specifically, the wheel (92)) moves. The sensor may be mounted on the robot (2) or the caster assembly (1). The control unit (100) may use the data received from the sensor to adjust (control) the rotational direction and rotational speed of the motor (12) in preset steps.

[0229] The control unit (100) of the present invention is composed of various electrical and electronic components. The electrical and electronic components include a printed circuit board (PCB), various semiconductor chips, memory, various sensors, wires, etc.

[0230] The control unit (100) can control the overall operation of the caster assembly (1) of the present invention by controlling the motor unit (10).

[0231] The control unit (100) can provide or process appropriate information or functions to the user by processing signals, data, information, etc. input or output through the motor unit (10) or by operating an application program stored in memory.

[0232] Additionally, the robot (2) having the caster assembly (1) of the present invention may be equipped with a user input unit (not shown).

[0233] The user input unit is for receiving information from a user, and when information is input through the user input unit, the control unit (100) can control the operation of the caster assembly (1) of the present invention to correspond to the input information.

[0234] Depending on the embodiment, one side of the inner spring (62) may not be fixed to the movable member (40). And, the other side of the inner spring (62) may or may not be fixed to the shaft member (70).

[0235] According to an embodiment, if the other side of the inner spring (62) is fixed to the shaft member (70), the caster assembly (1) of the present invention includes a spring fixing part (63) and a fixing member (64) that fix the other side of the inner spring (62) (see FIG. 12).

[0236] The spring fixing part (63) is formed into a plate shape of a preset size.

[0237] The spring fixing part (63) includes one side and the other side in the longitudinal direction.

[0238] The spring fixing member (63) fixes the inner spring (62). Specifically, the spring fixing member (63) fixes the other side of the inner spring (62) to the shaft member (70).

[0239] The spring fixing member (63) is fitted to the inner spring (62). At this time, the longitudinal direction of the spring fixing member (63) may be arranged orthogonal to the longitudinal direction of the inner spring (62) or obliquely.

[0240] To elaborate, one side of the spring fixing portion (63) contacts one side of the wire of the inner spring (62), and the other side of the spring fixing portion (63) contacts the other side of the wire of the inner spring (62). The one side wire and the other side wire represent wires that face each other in a direction perpendicular to the longitudinal direction of the inner spring (62).

[0241] The spring fixing member (63) may include one or more bends (631) in the longitudinal direction. Due to the bends (631), the spring fixing member (63) can be easily fitted into the inner spring (62).

[0242] And, the spring fixing part (63) includes a fixing hole (632).

[0243] The fixed hole (632) is a hole that penetrates the plate-shaped spring fixing part (63).

[0244] A fixing member (64) is inserted into the fixing hole (632).

[0245] The fixing member (64) may be, for example, a bolt, screw, pin, clip, etc.

[0246] The fixed member (64) is inserted into the fixed hole (632) and then fixed by being inserted into the fastening insertion part (731) of the shaft member (70) described later.

[0247] By fixing the fixed member (64) to the fastening insertion part (731) of the shaft member (70), the spring fixing part (63) is fixed to the shaft member (70), and the inner spring (62) into which the spring fixing part (63) is fitted is also fixed to the shaft member (70).

[0248] According to another embodiment (not shown), the spring fixing portion (63) may have a fixing hole (632) in the middle and may have a circular outer shape. When the spring fixing portion (63) is fitted into the inner spring (62), one side of the spring fixing portion (63) comes into contact with one side of the wire of the inner spring (62), and the other side of the spring fixing portion (63) comes into contact with the other side of the wire of the inner spring (62).

[0249] Referring to Figure 13, Figure 13 (a) is a top perspective view, Figure 13 (b) is a bottom perspective view, and Figure 13 (c) is a cross-sectional view.

[0250] The shaft member (70) can reciprocate a preset distance in one direction or in the opposite direction (e.g., upward or downward).

[0251] The shaft member (70) can move while being placed in the internal space (603) of the bush member (60).

[0252] The bush member (60) can guide the movement of the shaft member (70) and limit the movement of the shaft member (70) in a direction orthogonal to one direction (e.g., left and right direction).

[0253] The outer surface (or outer circumference) (74) of the shaft member (70) can slide while in contact with the inner surface (or inner circumference) of the bush member (60).

[0254] The shaft member (70) is formed into a rod shape having a preset length.

[0255] The shaft member (70) includes one side (71) and the other side (72). The one side (71) and the other side (72) face opposite sides in the longitudinal direction of the shaft member (70). For example, the one side (71) and the other side (72) may be an upper side and a lower side. The longitudinal direction of the shaft member (70) refers to a direction orthogonal to the one side (71) of the shaft member (70).

[0256] A one-sided groove (711) is formed on one side (71) of the shaft member (70).

[0257] A one-sided groove (711) is formed by recessing from one side (71) of the shaft member (70) toward the other side (72) to a preset depth.

[0258] A part of the outer spring (61) (specifically, the other side) and a part of the inner spring (62) (specifically, the other side) are placed in one side groove (711).

[0259] A groove (721) is formed on the other side (72) of the shaft member (70).

[0260] The other side groove (721) is formed by being sunk to a preset depth from the other side (72) of the shaft member (70) toward one side (71).

[0261] A screw groove (7211) may be formed on the inner surface (or inner circumference) of the other side groove (721).

[0262] The support shaft (93) of the caster (90) is placed in the other side home (721).

[0263] The shaft member (70) includes an internal bulkhead (73) and a fastening insert (731).

[0264] The inner partition (73) is a partition formed between one side groove (711) and the other side groove (721) and has a preset thickness. The inner partition (73) separates the one side groove (711) and the other side groove (721).

[0265] The fastening insert (731) is formed in the inner bulkhead (73).

[0266] The fastening insertion portion (731) may be formed in a groove shape or a hole shape. The groove shape indicates a recess from the bottom surface of one groove (711) toward the other groove (721) at a preset depth, and the hole shape indicates a passage connecting one groove (711) and the other groove (721).

[0267] A fixing member (64) is inserted into the fastening insertion portion (731) and fixed.

[0268] The fixing member (64) fixes the spring fixing member (63). When the spring fixing member (63) is fixed to the shaft member (70) by the fixing member (64), the inner spring (62) into which the spring fixing member (63) is fitted is fixed to the shaft member (70).

[0269] Meanwhile, a protrusion (711a) may be formed on the bottom surface of one side groove (711).

[0270] The protrusion (711a) is formed by protruding from the bottom surface of one side groove (711) toward one side surface (71) at a preset height.

[0271] The protrusion (711a) is inserted into the through hole (621) on the other side of the inner spring (62). By inserting the protrusion (711a) into the through hole (621) of the inner spring (62), the movement (movement) of the inner spring (62) itself can be restricted.

[0272] The protrusion (711a) is formed at a certain portion of the bottom surface of the one-sided groove (711) that surrounds the fastening insertion portion (731). As a result, the protrusion (711a) can be inserted into the through hole (621) of the inner spring (62).

[0273] Additionally, the shaft member (70) may be formed to have a different cross-sectional diameter in the longitudinal direction. The cross-sectional diameter refers to the diameter of the cross-section when the shaft member (70) is cut in a direction orthogonal to the longitudinal direction.

[0274] The boundary of the parts of the shaft member (70) with different cross-sectional diameters forms a step surface (741).

[0275] That is, the outer surface (or outer circumference) (74) of the shaft member (70) has a step surface (741). The outer surface (or outer circumference) (74) represents an external side connecting one side (71) and the other side (72) of the shaft member (70), and the step surface (741) represents a surface formed in a direction orthogonal to the outer surface (or outer circumference) (74).

[0276] With the step surface (741) as the boundary, the cross-sectional diameter of one side (71) of the shaft member (70) is formed to be wider than the cross-sectional diameter of the other side (72).

[0277] In addition, the cross-sectional diameter of one side (71) of the shaft member (70) is formed wider than the diameter of the holder hole (81) of the holder member (80) described later, and the cross-sectional diameter of the other side (72) of the shaft member (70) is formed narrower than the diameter of the holder hole (81).

[0278] Due to the step surface (741) formed on the outer surface (74), the shaft member (70) does not deviate toward the ground where the wheel (92) comes into contact even when moving in the up-and-down direction.

[0279] The step surface (741) of the shaft member (70) is restricted from moving toward the ground by the body of the holder member (80) surrounding the holder hole (81) of the holder member (80). That is, the step surface (741) of the shaft member (70) cannot move outward by penetrating the holder hole (81).

[0280] Fig. 14 shows a holder member (80). The holder member (80) supports and fixes the components accommodated in the internal space (24) of the bracket portion (20) so that the components do not escape to the outside.

[0281] When the outer member (50), bush member (60), outer spring (61), inner spring (62) and shaft member (70) are accommodated in the inner space (24) of the bracket part (20), the bracket part (20) (specifically, the fastening groove (2222)) and the caster housing (30) (specifically, the housing fastening hole (312)) are joined by the fastening member (p).

[0282] The holder member (80) is placed inside the caster housing (30) and supports the components accommodated in the internal space (24) of the bracket portion (20).

[0283] Above all, the holder member (80) limits the shaft member (70) from moving toward the ground.

[0284] The holder member (80) is formed in a plate shape. In addition, when viewed from above, the holder member (80) is formed in a circular ring shape with a through hole in the middle (referred to as a 'holder hole (81)').

[0285] That is, the outer and inner surfaces of the holder member (80) can be formed in a circular shape. The outer surface of the holder member (80) represents the outer surface located at the outermost edge, and the inner surface of the holder member (80) represents the inner surface surrounding the holder hole (81).

[0286] The space between the outer and inner surfaces of the holder member (80) is formed into a plate shape of a preset size.

[0287] When the holder member (80) is placed inside the caster housing (30), the holder hole (81) is placed below the housing upper hole (311) of the caster housing (30).

[0288] When the outer member (50) and the caster housing (30) are combined and the outer fastening portion (522) of the outer member (50) is placed in the internal space (34) of the caster housing (30), the holder member (80) is placed below the outer fastening portion (522). At this time, from top to bottom, the upper housing hole (311), the outer lower hole (521), and the holder hole (81) of the caster housing (30) are placed.

[0289] According to an embodiment, the outer surface of the holder member (80) may be formed with one or more grooves (referred to as 'outer surface grooves (83)').

[0290] Specifically, the outer circumferential groove (83) is formed by being sunken from the outer circumferential surface of the holder member (80) toward the inner circumferential surface to a preset depth.

[0291] When a plurality of outer grooves (83) are formed, the adjacent outer grooves (83) are spaced apart by a preset distance, and the preset distance may be different for each outer groove (83).

[0292] In the outer groove (83), a fastening member (p) that connects the bracket part (20) and the caster housing (30) is arranged. Accordingly, the holder member (80) does not interfere with the fastening member (p).

[0293] A plurality of holder fastening holes (82) are formed between the outer and inner surfaces of the holder member (80).

[0294] A plurality of holder fastening holes (82) are arranged at a preset distance in the circumferential direction of the holder member (80).

[0295] A fastening member (p) (e.g., a bolt or screw) is placed in the holder fastening hole (82).

[0296] The holder fastening hole (82) of the holder member (80), the outer fastening hole (5222) of the outer member (50), the housing fastening hole (312) of the caster housing (30) and / or the fastening groove (2222) of the bracket portion (20) may be in communication with each other.

[0297] The fastening member (p) can be inserted and fixed into the holder fastening hole (82), the outer fastening hole (5222) of the outer member (50), and the housing fastening hole (312) of the caster housing (30).

[0298] Alternatively, another fastening member (p) may be inserted and fixed into the holder fastening hole (82), the outer fastening hole (5222) of the outer member (50), the housing fastening hole (312) of the caster housing (30), and the fastening groove (2222) of the bracket portion (20).

[0299] Referring to FIGS. 1 to 5, the caster (90) supports and moves the robot (2) equipped with the caster (90).

[0300] The caster (90) includes a support body (91), a wheel (92), and a support shaft (93).

[0301] The support body (91) constitutes the body of the caster (90). The support body (91) is not limited to a specific shape.

[0302] A wheel (92) is rotatably connected to one or both sides of the support body (91). The method of connecting the support body (91) and the wheel (92) is according to a known technology.

[0303] The wheel (92) rotates. As the wheel (92) rotates, the robot (2) equipped with the caster (90) can move.

[0304] A support shaft portion (93) is attached to one surface (e.g., the upper surface) of the support body (91).

[0305] The support shaft portion (93) is formed in a rod shape of a preset length. For example, the support shaft portion (93) may be formed in a circular column shape of a preset length.

[0306] The support shaft portion (93) includes one side and the other side. The one side and the other side face opposite sides in the longitudinal direction of the support shaft portion (93).

[0307] One side of the support shaft (93) is connected to the shaft member (70).

[0308] Specifically, one side of the support shaft (93) passes through the holder hole (81) of the holder member (80) and is then inserted into the groove (721) of the other side of the shaft member (70) and fixed.

[0309] A screw thread (931) may be formed on the outer surface (or outer circumference) of one side of the support shaft portion (93). The screw thread (931) may be combined with a screw groove (7211) formed in the groove (721) on the other side of the shaft member (70).

[0310] The other side of the support shaft (93) is connected to one surface (e.g., the upper surface) of the support body (91).

[0311] According to an embodiment, the support shaft portion (93) can rotate while connected to the support body (91). That is, the support shaft portion (93) and the support body (91) can rotate relative to each other. The rotation is performed in a direction orthogonal to the longitudinal direction of the support shaft portion (93) (e.g., left-right direction).

[0312] A washer member (94) can be placed on the support shaft (93) (see FIGS. 4 to 6 and FIG. 15).

[0313] The washer member (94) serves to fix the support shaft member (93) so that the support shaft member (93) does not come loose (fall out) from the other side groove (721) of the shaft member (70).

[0314] The washer member (94) is formed in a ring shape with a hole in the center, and the support shaft part (93) is fitted into the hole.

[0315] The washer member (94) represents a commonly used washer.

[0316] When the wheel (92) rotates while in contact with the ground (floor surface), the caster (90) may receive pressure (impact force) from the ground depending on the condition of the ground. The condition of the ground refers to the shape of the ground (e.g., curves, slopes, steps) and liquids or other obstacles on the ground.

[0317] At this time, the caster (90) and the shaft member (70) connected to the caster (90) can move up or down by the outer spring (61) and the inner spring (62) supported by the shaft member (70).

[0318] The caster assembly (1) of the present invention described above can be equipped on a robot (2).

[0319] A robot (2) having a caster assembly (1) of the present invention represents a robot used for various purposes.

[0320] For example, a robot (2) having a caster assembly (1) of the present invention may be a robot that transports people or objects, or a robot that transports food.

[0321] For example, as shown in Fig. 1, when a robot (2) having a caster assembly (1) of the present invention transports food, the caster assembly (1) of the present invention can change the value of the spring constant applied to the caster (90) by using an outer spring (61) and an inner spring (62).

[0322] Specifically, the value of the spring constant of the inner spring (62) provided in the caster assembly (1) can be changed depending on the condition of the ground.

[0323] When the robot (2) is carrying food, and the robot (2) passes over a curved, inclined, or stepped area, the shaft member (70) of the present invention can support only the outer spring (61) to prevent the food in the bowl from overflowing. At this time, the spring constant value of the outer spring (61) may be low. In addition, the moving speed of the robot (2) may not be fast.

[0324] When the robot (2) moves at a high speed, the robot (2) shakes back and forth when the robot (2) accelerates or decelerates due to the low spring constant value, and when the robot (2) suddenly stops, the objects or food in the tray spill forward due to the shaking of the robot (2).

[0325] Meanwhile, when the robot (2) moves in a state where there is no food in the robot (2), the shaft member (70) of the present invention can support the outer spring (61) and the inner spring (62). At this time, the inner spring (62) contracts in the longitudinal direction, so that the value of the spring constant of the inner spring (62) increases. Accordingly, the robot (2) can move without shaking.

[0326] In detail, in the case where the robot (2) having the caster assembly (1) of the present invention is a robot transporting food, when the robot (2) passes over a curved, inclined, or stepped area while food is present in the robot (2), only the outer spring (61) of the caster assembly (1) of the present invention operates. The robot (2) of the present invention can prevent food from overflowing out of the tray by lowering the spring constant value of the caster assembly (1). In addition, the robot (2) can lower the moving speed.

[0327] Alternatively, when the robot (2) passes over a flat surface while there is food in the robot (2), the caster assembly (1) of the present invention operates with the outer spring (61) and the inner spring (62) together. The robot (2) of the present invention can move at a high speed while preventing food from overflowing out of the tray by increasing the spring constant value of the caster assembly (1).

[0328] Alternatively, when the robot (2) moves in a state where there is no food in the robot (2), the caster assembly (1) of the present invention operates with the outer spring (61) and the inner spring (62) together. The robot (2) of the present invention can move at a high speed while preventing the robot (2) from falling over due to shaking by increasing the spring constant value of the caster assembly (1).

[0329] As described above, in the case where the caster assembly (1) of the present invention operates with the outer spring (61) and the inner spring (62) together (when the spring constant value is high), the moving member (40) rotates in one rotational direction and moves toward the inner spring (62).

[0330] As the moving member (40) continues to move toward the inner spring (62), the inner spring (62) is compressed and contracted in the longitudinal direction, and the value of the spring constant of the inner spring (62) increases.

[0331] And, in the case where the caster assembly (1) of the present invention operates only the outer spring (61) (when the value of the spring constant is low), the moving member (40) rotates in the opposite direction of the rotation direction and moves toward the motor unit (10).

[0332] As the moving member (40) continues to move toward the motor unit (10), the length of the inner spring (62) is restored to its original length, and the value of the spring constant of the inner spring (62) gradually decreases to its original value.

[0333] And, when the moving member (40) completes moving toward the motor unit (10), one side of the inner spring (62) is separated from the bottom surface (4211) of the lower groove (421) of the moving member (40). Therefore, the shaft member (70) supports only the outer spring (61).

[0334] As described above, the caster assembly (1) of the present invention can perform a variable suspension function that can change the value of the spring constant.

[0335] Accordingly, for example, a food delivery robot (2) to which the caster assembly (1) of the present invention is applied can prevent food from overflowing and deliver quickly.

Claims

1. Motor section; A moving member moved by the above motor unit; An outer member in which the above movable member is arranged to be rotatable and movable; A movable shaft member arranged in the inner space of the outer member; An outer spring disposed between the outer member and the shaft member and supported by the shaft member; An inner spring disposed between the movable member and the shaft member, supported by the shaft member, and disposed in the through hole of the outer spring; and Including a caster connected to the above shaft member, When the above moving member moves toward the inner spring, the inner spring is compressed and contracted in the longitudinal direction, A caster assembly in which the length of the inner spring is restored to its original length when the above-mentioned moving member moves toward the above-mentioned motor unit.

2. In paragraph 1, The above moving member is, An extension formed on one side; a lower groove formed on the other side; and Including a movable member hole connecting the above one side and the lower groove, The rotating member of the above motor part is inserted into the hole of the above moving member, A caster assembly in which when the above-mentioned rotating member rotates, the above-mentioned moving member rotates and moves toward the inner spring or moves toward the motor unit.

3. In paragraph 2, A caster assembly in which, when the movable member moves toward the inner spring, an extension of the movable member comes into contact with one side of the outer member, so that the movable member is restricted from moving.

4. In paragraph 2, A caster assembly, wherein when the movable member moves toward the inner spring, one side of the inner spring comes into contact with the bottom surface of the lower groove of the movable member.

5. In paragraph 2, The above rotating member is formed to include a de-cut shape, A caster assembly in which the above moving member hole is formed in a D shape corresponding to the cut shape of the above rotating member.

6. In paragraph 5, A caster assembly in which, when the movable member moves toward the motor unit, one side of the movable member or the bottom surface of the upper groove formed on the one side comes into contact with the end of the die-cut shape formed on the rotating member, so that the movable member is restricted from moving.

7. In paragraph 2, The above moving member includes a screw thread formed on the outer surface between the one side and the other side, The above outer member includes an outer upper hole in which the movable member is arranged to be rotatable and movable, A screw groove is formed on the inner surface of one side of the outer member surrounding the upper hole of the outer member, A caster assembly in which the screw thread of the above movable member engages with the screw groove of the above outer member.

8. In paragraph 7, A caster assembly, wherein when the movable member is coupled with the outer upper hole, the extension of the movable member is disposed on the outside of the outer member, and the screw thread of the movable member is disposed in the outer upper hole.

9. In paragraph 1, The above shaft member includes a one-sided groove formed on one side; and an other-sided groove formed on the other side, A part of the outer spring and a part of the inner spring are arranged in the above one-sided groove, A caster assembly in which the support shaft of the caster is placed in the groove on the other side.

10. In paragraph 9, The above shaft member includes a stepped surface formed on the outer surface, A caster assembly in which the cross-sectional diameter of one side of the shaft member is formed wider than the cross-sectional diameter of the other side, with the step surface as the boundary.

11. In paragraph 10, A holder member is disposed below the shaft member and has a holder hole formed in the middle, A caster assembly in which the cross-sectional diameter of one side of the shaft member is formed wider than the diameter of the holder hole, and the cross-sectional diameter of the other side of the shaft member is formed narrower than the diameter of the holder hole.

12. In paragraph 11, A caster assembly in which the support shaft portion of the caster is inserted into the other side groove of the shaft member and fixed by penetrating the holder hole of the holder member.

13. In paragraph 9, A caster assembly, wherein one side of the outer spring contacts the inner surface of one side of the outer member, and the other side of the outer spring contacts the bottom surface of the one side groove of the shaft member.

14. In paragraph 9, A caster assembly wherein the inner spring is fixed to the groove on one side of the shaft member.

15. In paragraph 1, Including a bush member arranged in the inner space of the outer member, A caster assembly in which the outer spring, the inner spring, and the shaft member are arranged in the inner space of the bush member.

16. In paragraph 1, Includes a control unit that controls the motor of the above motor unit, A caster assembly in which the control unit controls the direction of rotation and the rotational speed of the motor to control the direction of movement and the distance of movement of the movable member.

17. A robot having a caster assembly according to any one of claims 1 to 16.

Images