Speed suppression device and vehicle

Abstract

The invention provides a speed suppression device and a vehicle. This speed suppression device (1) is provided with: a brake drum (11); a brake shoe (23) that reduces the rotational speed of the wheel by means of a braking force generated by contact with the inner peripheral surface of the brake drum (11); an elastic member (24) that biases the brake shoe (23); an abutment member (25); a shift cam (26) that increases or decreases the force of the contact member (25) pressing the elastic member (24); and an adjustment gear (27) that adjusts the force pressing the elastic member (24) by determining the rotational position of the shift cam (26). The diameter (D1) of the shift cam (26) is larger than the diameter (D2) of the adjustment gear (27).

Description

Technical Field

[0001] The present invention relates to a speed suppression device and a vehicle. Background Art

[0002] For example, a vehicle such as a walking vehicle used to assist a user in walking may be provided with a speed control device that controls the rotation speed of a wheel (for example, see Patent Document 1).

[0003] The speed control device is provided on the wheel. The speed control device includes, for example, a brake drum, a brake shoe, an elastic member, a contact member, a cam, and an adjustment gear. The brake shoe contacts the inner peripheral surface of the brake drum. The elastic member applies force to the brake shoe. The cam applies a force in a compression direction to the elastic member by means of the contact member. The adjustment gear adjusts the force of the contact member pressing the elastic member by determining the position of the cam in the rotation direction.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2022-59838 Summary of the invention

[0007] Problem that the invention aims to solve

[0008] In the speed control device, increasing the adjustment range of the braking force is studied. If the adjustment range of the braking force can be increased, for example, the braking force can be set to act when the vehicle is traveling at a high speed.

[0009] However, in conventional speed control devices, it is difficult to increase the adjustment range of the braking force due to its structure.

[0010] One aspect of the present invention provides a speed control device and a vehicle capable of increasing the adjustment range of the braking force.

[0011] Solutions for solving problems

[0012] A speed control device according to one aspect of the present invention is a speed control device which is provided on a wheel rotating about a rotation axis and controls the rotation speed of the wheel, wherein the speed control device comprises: a brake drum; a brake shoe which reduces the rotation speed of the wheel by a braking force generated by contact with the inner peripheral surface of the brake drum; an elastic member having one end and the other end, and applying force to the brake shoe by means of the one end; an abutment member provided to the other end of the elastic member; a shift cam which is configured to be rotatable about the rotation axis and to increase or decrease the force of the abutment member pressing the elastic member according to the rotation position; and an adjustment gear which operates by external input, thereby rotating the shift cam, determining the rotation position of the shift cam, and adjusting the force pressing the elastic member. The diameter of the shift cam is larger than the diameter of the adjustment gear.

[0013] In the speed control device, the outer diameter of the shift cam is larger than the outer diameter of the adjustment gear, so the adjustment range of the brake force can be increased. In addition, the degree of freedom in setting the brake force can be increased. Therefore, for example, it is possible to set the brake force to act when the vehicle is traveling at a higher speed than before.

[0014] The speed control device may further include a cover plate that covers at least the shift cam. The cover plate may include at least one window portion that displays a rotational position of the shift cam.

[0015] In this case, the braking force of the centrifugal brake can be displayed in an easily visible manner by using the window portion. Therefore, the operation such as setting the rotation speed of the wheel on which the centrifugal brake is activated becomes easy.

[0016] In the speed control device, the window portion may be formed in plurality. Alternatively, the plurality of window portions may be formed in a manner of being arranged at different positions along the rotation direction of the shift cam, and the number of the window portions overlapping the shift cam may vary according to the rotation position of the shift cam.

[0017] In this case, the braking force of the centrifugal brake can be displayed in a more easily understandable manner.

[0018] In the speed control device, a position mark indicating a rotation position of the shift cam may be formed on the shift cam. The window portion may be formed so that the position mark can be visually recognized.

[0019] In this case, the braking force of the centrifugal brake can be displayed in a more easily understandable manner.

[0020] A vehicle according to one aspect of the present invention includes the speed control device and a wheel provided with the speed control device.

[0021] According to the vehicle, since the speed control device is provided, the adjustment range of the braking force can be increased. Therefore, the degree of freedom in setting the braking force can be increased.

[0022] Effects of the Invention

[0023] According to one aspect of the present invention, the adjustment range of the braking force can be increased. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a structural diagram of a walking vehicle as a vehicle according to an embodiment.

[0025] Figure 2 It is an exploded perspective view of the speed control device and wheels according to the first embodiment.

[0026] Figure 3 yes Figure 2 A plan view of the centrifugal brake unit is shown.

[0027] Figure 4 yes Figure 2 A plan view of the shroud panel is shown.

[0028] Figure 5 It is a partial plan view of the speed control device according to the first embodiment.

[0029] Figure 6 It is a partial plan view of the speed control device according to the first embodiment.

[0030] Figure 7 It is a partial plan view of the speed control device according to the first embodiment.

[0031] Figure 8 It is a partial plan view of the speed control device according to the first embodiment.

[0032] Fig. 9 It is a partial plan view of the speed control device according to the second embodiment.

[0033] Fig.10 It is a partial plan view of the speed control device according to the second embodiment.

[0034] Fig.11 It is a partial plan view of the speed control device according to the second embodiment.

[0035] Fig.12 It is a partial plan view of the speed control device according to the second embodiment.

[0036] Fig.13It is a partial plan view of the speed control device according to the second embodiment.

[0037] Fig.14 It is a partial plan view of the shift cam of the speed control device according to the second embodiment.

[0038] Fig.15 It is an exploded perspective view showing a modified example of the speed control device and the wheel according to the embodiment.

[0039] Fig.16 yes Fig.15 Six-sided view of the wheel shown.

[0040] Fig.17 yes Fig.15 A perspective view of the wheel is shown.

[0041] Description of Reference Numerals

[0042] 1. 201. 250. speed suppression device; 11. brake drum; 20. axis of rotation; 23. brake shoe; 24. spring (elastic member); 25. abutment member; 26. 226. shift cam; 27. adjustment gear; 28. 228. cover plate; 40. 40a to 40d. 240. window; 241. 241a to 241d. position mark; 103. wheel; D1. D201. outer diameter (diameter of shift cam); D2. D202. outer diameter (diameter of adjustment gear). DETAILED DESCRIPTION

[0043] Hereinafter, a speed control device according to an embodiment of the present invention will be described in detail with reference to the drawings.

[0044] [vehicle]

[0045] Figure 1 It is a structural diagram of a walking vehicle 101 as a vehicle according to the embodiment.

[0046] The walking vehicle 101 is used, for example, to assist the user in walking. In this embodiment, the up-down direction is defined in the use state of the walking vehicle 101. In addition, the travel direction of the walking vehicle 101 in the use state is defined as the front, and the direction opposite to the travel direction is defined as the rear. The direction orthogonal to the up-down direction and the front-back direction is also defined as the vehicle width direction of the walking vehicle 101.

[0047] The walking vehicle 101 includes a vehicle body 102, a plurality of wheels 103, and an operating unit 104. The vehicle body 102 includes a lower frame 105 and a plurality of longitudinal frames 106. The lower frame 105 includes a front frame 107 and two side frames 108. The side frames 108 extend rearward from both ends of the front frame 107. The plurality of longitudinal frames 106 extend upward from the front and rear portions of the side frames 108. The wheels 103 are provided at the front and rear portions of the side frames 108. The operating unit 104 is provided in a U shape. The operating unit 104 is connected to the upper ends of the longitudinal frames 106.

[0048] The walking vehicle 101 travels when a user pushes the operation unit 104 by hand.

[0049] In this embodiment, as an example of a vehicle, the walking vehicle 101 is described. However, the vehicle is not limited to the walking vehicle, and may be, for example, a cart for transporting goods, a stroller for infants, etc.

[0050] (First embodiment)

[0051] [Speed ​​Suppression Device]

[0052] Figure 2 It is an exploded perspective view of the speed control device 1 and the wheel 103 according to the first embodiment. Figure 3 It is a plan view of the centrifugal brake unit 13 constituting the speed control device 1 . Figure 4 It is a plan view of the cover plate 28 constituting the speed control device 1 . Figures 5 to 8 It is a plan view of a part of the speed control device 1 .

[0053] like Figure 1 As shown, the wheel 103 is provided on a bracket 109 provided to the lower part of the front and rear parts of the side frame 108. Thus, the wheel 103 is fixed to the vehicle body 102 via the bracket 109.

[0054] In addition, the plurality of wheels 103 provided to the vehicle body 102 are set to the same structure. Therefore, in the following description, only one of the plurality of wheels 103 is described, and the description of the other wheels 103 is omitted.

[0055] like Figure 1 and Figure 2 As shown, the wheel 103 includes an axle 21 supported by a bracket 109 , a disk-shaped wheel 50 rotatably supported by the axle 21 , and a tire 51 attached to the outer peripheral surface of the wheel 50 .

[0056] The axle 21 is formed so as to protrude from the bracket 109 toward the outside in the vehicle width direction. The axle 21 is arranged so that the axial direction of the axle 21 coincides with the vehicle width direction. In addition, a central axis passing through the center of the axle 21 in the vehicle width direction is set as a rotation axis 20. Therefore, the wheel 103 rotates around the rotation axis 20.

[0057] Furthermore, a direction intersecting the rotation axis 20 as viewed from the rotation axis 20 is defined as a radial direction, and a direction circling around the rotation axis 20 is defined as a circumferential direction.

[0058] The wheel 50 includes a first wheel plate 60 and a second wheel plate 70 which are overlapped in the axial direction of the axle 21. The first wheel plate 60 and the second wheel plate 70 are formed in a disk shape and are rotatably supported on the axle 21.

[0059] The first wheel plate 60 is arranged at a position closer to the bracket 109 than the second wheel plate 70. The first wheel plate 60 includes: a bottomed cylindrical first housing portion 61 which is open toward the second wheel plate 70; a cylindrical first rim portion 62 which is arranged to surround the first housing portion 61 from the outside in the radial direction; and a plurality of first spoke portions 63 which connect the first housing portion 61 and the first rim portion 62 in the radial direction.

[0060] The first storage portion 61 includes: a first bottom wall 61a in a disk shape; and a first peripheral wall 61b, which protrudes from the outer peripheral edge of the first bottom wall 61a toward the second wheel plate 70 side and is formed along the outer peripheral edge of the first bottom wall 61a over the entire circumference. The internal space of the first storage portion 61 functions as a first storage space R1 opened toward the second wheel plate 70 side.

[0061] The first bottom wall 61a is provided with a bearing housing 64 which accommodates a bearing (not shown) therein. The bearing housing 64 is coaxially arranged with the rotation axis 20 and is formed into a cylindrical shape so as to protrude inward in the vehicle width direction. Thus, the first wheel plate 60 is rotatably supported on the axle 21 by the bearing accommodated in the bearing housing 64.

[0062] In addition, a plurality of first planetary support pins 65 are integrally formed on the first bottom wall 61a. In the example shown in the figure, three first planetary support pins 65 are formed at equal intervals in the circumferential direction with the rotation axis 20 as the center. The first planetary support pins 65 are formed in a manner protruding from the first bottom wall 61a toward the second wheel plate 70 side. In addition, the first planetary support pins 65 constitute a part of the speed control device 1.

[0063] Three first spokes 63 are formed at equal intervals in the circumferential direction with the rotation axis 20 as the center. The first spokes 63 are formed to extend from the outer circumferential surface of the first peripheral wall 61b toward the radial outer side, and are connected to the inner circumferential surface of the first rim 62. The first spokes 63 are formed so that the circumferential width along the circumferential direction gradually decreases toward the radial outer side.

[0064] However, the number and shape of the first spoke portion 63 are not limited to this, and may be changed as appropriate. In addition, the first spoke portion 63 is formed with a bolt insertion hole 63 a that penetrates the first spoke portion 63 in the vehicle width direction.

[0065] The second wheel plate 70 comprises: a second cylindrical housing portion 71 with a bottom, which is open toward the first wheel plate 60; a cylindrical second rim portion 72, which is arranged in a manner of surrounding the second housing portion 71 from the radial outside; and a plurality of second spoke portions 73, which radially connect the second housing portion 71 and the second rim portion 72.

[0066] The second storage portion 71 includes: a disk-shaped second bottom wall 71a; and a second peripheral wall 71b, which protrudes from the outer peripheral edge of the second bottom wall 71a toward the first wheel plate 60 side and is formed along the outer peripheral edge of the second bottom wall 71a on the entire circumference. The internal space of the second storage portion 71 functions as a second storage space (not shown) that opens toward the first wheel plate 60 side.

[0067] The second bottom wall 71a is provided with an opening 19 that penetrates the second bottom wall 71a in the vehicle width direction. The opening 19 functions as a visual recognition window for visually recognizing a window portion 40 of a cover panel 28 to be described later from the outside.

[0068] Furthermore, a cylindrical cover mounting portion 75 protruding outward in the vehicle width direction is integrally formed on the second bottom wall 71 a . Thus, the opening 19 is arranged inside the cover mounting portion 75 .

[0069] The second housing portion 71 configured as described above is formed in a bottomed cylindrical shape having the same outer diameter as the first housing portion 61. The second housing portion 71 is disposed so as to face the first housing portion 61 from the outside in the vehicle width direction.

[0070] Three second spokes 73 are formed at equal intervals in the circumferential direction with the rotation axis 20 as the center. The second spokes 73 are formed to extend from the outer circumferential surface of the second peripheral wall 71b toward the radial outer side, and are connected to the inner circumferential surface of the second rim 72. The second spokes 73 are formed so that the circumferential width along the circumferential direction gradually decreases toward the radial outer side.

[0071] In particular, the second spoke portion 73 is formed to be the same in number, shape, size, etc. as the first spoke portion 63 , and is arranged to face the first spoke portion 63 from the outside in the vehicle width direction.

[0072] Furthermore, a bolt hole (threaded hole) (not shown) opened toward the inner side in the vehicle width direction is formed in the second spoke portion 73. The bolt hole faces the bolt insertion hole 63a formed in the first spoke portion 63 in the vehicle width direction.

[0073] The first wheel plate 60 and the second wheel plate 70 constructed as described above are coaxially stacked and fixed by bolts (not shown). Thus, the wheel 50 is formed by integrally combining the first wheel plate 60 and the second wheel plate 70. In addition, the bolt passes through the bolt through hole 63a from the inner side in the vehicle width direction and is threadedly engaged with the bolt hole.

[0074] In addition, the opening of the first storage space R1 overlaps with the opening of the second storage space due to the combination of the first wheel plate 60 and the second wheel plate 70. Thus, inside the wheel 50, an internal storage space R is formed by the first storage space R1 and the second storage space.

[0075] Furthermore, due to the combination of the first wheel plate 60 and the second wheel plate 70 , the first spoke portion 63 and the second spoke portion 73 are combined to function as the spoke portion 55 .

[0076] The tire 51 is integrally combined with the wheel 50 formed by the combination of the first wheel plate 60 and the second wheel plate 70 in a manner of surrounding the wheel 50 from the radially outer side. Specifically, the tire 51 is combined with the wheel 50 in a state where the inner peripheral surface is in contact with the outer peripheral surface of the wheel 50 (the outer peripheral surface of the first rim portion 62 in the first wheel plate 60 and the outer peripheral surface of the second rim portion 72 in the second wheel plate 70) from the radially outer side.

[0077] The speed control device 1 is disposed in the internal housing space R of the wheel 50 described above. The speed control device 1 includes a planetary gear mechanism 80 , an internal gear 90 , a brake drum 11 , a centrifugal brake unit 13 , and a cover 15 .

[0078] The planetary gear mechanism 80 is a two-stage structure, and is mainly arranged in the first storage space R1 of the first wheel plate 60. The planetary gear mechanism 80 includes: a first-stage gear mechanism 110, which is arranged on the first bottom wall 61a of the first storage portion 61; and a second-stage gear mechanism 120, which is arranged at a position outside the first-stage gear mechanism 110 in the vehicle width direction.

[0079] The first-stage gear mechanism 110 includes: a first sun gear (not shown) rotatably supported on the axle 21; and a plurality of first planetary gears 111 arranged around the first sun gear. The first sun gear is formed integrally with the second planetary gear carrier 122 discussed later. Three first planetary gears 111 are arranged at equal intervals in the circumferential direction with the rotation axis 20 as the center, and are respectively meshed with the first sun gear. Moreover, the first planetary gears 111 are respectively rotatably supported on the first planetary support pins 65 integrally formed with the first bottom wall 61a of the first housing portion 61. Therefore, the first bottom wall 61a functions as a planetary gear carrier that rotatably supports the plurality of first planetary gears 111.

[0080] The second stage gear mechanism 120 includes: a second sun gear (not shown) rotatably supported on the axle 21; a plurality of second planetary gears 121 arranged around the second sun gear; and a second planetary gear carrier 122 rotatably supporting the plurality of second planetary gears 121. The second sun gear is formed integrally with a support plate 29 (described later) constituting the centrifugal brake unit 13, and is arranged in a manner aligned with the first sun gear in the vehicle width direction.

[0081] The second planetary gear carrier 122 includes a disc-shaped gear carrier plate 123 and a second planetary support pin 124 protruding from the gear carrier plate 123 toward the outside in the vehicle width direction. The first sun gear protruding toward the inside in the vehicle width direction is formed on the gear carrier plate 123. The second planetary support pin 124 corresponds to the first planetary support pin 65, and three of them are formed in a state of being equally spaced in the circumferential direction with the rotation axis 20 as the center. In addition, the second planetary support pin 124 constitutes a part of the speed control device 1.

[0082] Three second planetary gears 121 are arranged at equal intervals in the circumferential direction around the rotation axis 20 , and each of the second planetary gears 121 meshes with the second sun gear. Each of the second planetary gears 121 is rotatably supported by a second planetary support pin 124 formed on the second planetary carrier 122 .

[0083] The internal gear 90 is formed in a cylindrical shape surrounding the first planetary gear 111 of the first-stage gear mechanism 110 and the second planetary gear 121 of the second-stage gear mechanism 120. Internal teeth are continuously formed over the entire circumference of the inner circumferential surface of the internal gear 90. The internal teeth mesh with the first planetary gear 111 and the second planetary gear 121.

[0084] The brake drum 11 is arranged at a position on the outside of the internal gear 90 in the vehicle width direction. The brake drum 11 is formed into a bottomed cylindrical shape having a cylindrical portion 11a and a bottom portion 11b, and is arranged with the opening facing the inside (the side of the internal gear 90) in the vehicle width direction. The cylindrical portion 11a of the brake drum 11 surrounds the internal gear 90 from the outside in the radial direction. And the inner peripheral surface of the cylindrical portion 11a is fitted with the outer peripheral surface of the internal gear 90. Thus, the internal gear 90 and the brake drum 11 are combined into one body.

[0085] A through hole (not shown) is formed in the center of the bottom 11b and penetrates the bottom 11b in the vehicle width direction. The through hole is formed coaxially with the rotation axis 20. In addition, a bushing provided to the axle 21, for example, is pressed into the through hole. Thus, the brake drum 11 is fixed integrally with the axle 21. Therefore, the internal gear 90 is fixed integrally to the axle 21 via the brake drum 11.

[0086] The bottom 11 b is provided with a plurality of operation windows 11 c that penetrate the bottom 11 b in the vehicle width direction, so that the outside of the wheel 103 and the inside of the brake drum 11 are connected via the operation windows 11 c and the opening 19 formed in the second wheel plate 70 .

[0087] The cover 15 is detachably mounted on the cover mounting portion 75 of the second wheel plate 70. Therefore, the cover 15 normally covers the opening 19.

[0088] The centrifugal brake unit 13 is arranged inside the brake drum 11 and outside the planetary gear mechanism 80 in the vehicle width direction. Specifically, the centrifugal brake unit 13 is arranged inside the cylindrical portion 11a of the brake drum 11 and between the second stage gear mechanism 120 and the bottom portion 11b of the brake drum 11.

[0089] The centrifugal brake unit 13 is a mechanism for generating a braking force (Brake force) of a centrifugal brake between the centrifugal brake unit 13 and the brake drum 11. The centrifugal brake unit 13 is rotatable around a rotation axis 20.

[0090] like Figure 3 and Figure 4 As shown, the centrifugal brake unit 13 includes two brake shoes 23, two springs 24 (elastic members), two abutment members 25, a shift cam 26, two adjustment gears 27, a cover plate 28, and a support plate 29. Figure 3 The axle 21 is omitted in the figure.

[0091] like Figure 3As shown in FIG. 1 , the brake shoe 23 is formed in a long plate shape along the circumferential direction that turns around the rotation axis 20. The brake shoe 23 is supported on the support plate 29 in a rotatable manner by means of a rotation shaft 31. The rotation shaft 31 is arranged at a position offset from the center of the brake shoe 23 in the longitudinal direction to one end side. One end of the brake shoe 23 is urged toward the radial outer side of the support plate 29 by the spring 24. The two brake shoes 23 are arranged in a manner opposite to each other in the radial direction of the support plate 29 with the center (rotation axis 20) of the support plate 29 sandwiched therebetween.

[0092] also, Figure 2 The brake shoe 23 shown is Figure 3 The brake shoe 23 shown shows a case where a different rotation shaft 31 is used, but only the rotation direction is different, and the basic structure and operation are the same.

[0093] The brake shoe 23 is formed with an outer peripheral surface that is curved along the length direction of the brake shoe 23. A pad 30 is mounted on the outer peripheral surface of the other end of the brake shoe 23. The pad 30 is provided on the opposite side of the end of the brake shoe 23 that is biased by the spring 24, with the rotation shaft 31 located in the middle. When the rotation speed of the wheel 103 increases, the brake shoe 23 rotates around the rotation shaft 31, so that the pad 30 contacts the inner peripheral surface of the cylindrical portion 11a of the brake drum 11. The brake shoe 23 reduces the rotation speed of the wheel 103 by the braking force generated by the contact with the inner peripheral surface of the brake drum 11.

[0094] The spring 24 is, for example, a coil spring, and has one end and the other end. The spring 24 is disposed between one end of the brake shoe 23 and the abutment member 25. The spring 24 is disposed along the radial direction of the support plate 29. One end of the spring 24 abuts against one end of the brake shoe 23, and urges the one end of the brake shoe 23 toward the radial outer side of the support plate 29. The two springs 24 are disposed opposite to each other in the radial direction of the support plate 29, sandwiching the center (rotation axis 20) of the support plate 29.

[0095] The spring 24 prevents the brake drum 11 from contacting the brake shoe 23 when the rotation speed of the wheel 103 is below a predetermined speed, thereby reducing the braking force. The spring 24 allows the brake drum 11 to contact the brake shoe 23 when the rotation speed of the wheel 103 exceeds the predetermined speed, thereby increasing the braking force.

[0096] In addition, the spring 24 is covered by the protective cover 22 attached to the support plate 29. Thus, the spring 24 is protected by the protective cover 22, and the adhesion of dust and the like to the spring 24 is suppressed. Figure 2 A protective cover 22 covering the spring 24 is shown in the figure.

[0097] The abutment member 25 is provided at the other end portion (the portion on the opposite side to the one end portion) of the spring 24. The two abutment members 25 are arranged to face each other in the radial direction of the support plate 29 with the center (rotation axis 20) of the support plate 29 sandwiched therebetween. The abutment member 25 is provided to be movable along the expansion and contraction direction of the spring 24.

[0098] The shift cam 26 is mounted to be rotatable with respect to the support plate 29 about the rotation axis 20. The shift cam 26 directly or indirectly contacts the contact member 25. The shift cam 26 increases or decreases the force of the contact member 25 pressing the spring 24.

[0099] Meshing portions 32 are formed at two locations on the outer periphery of the shift cam 26. The meshing portion 32 has a plurality of teeth 32a. The two meshing portions 32 are arranged to face each other in the radial direction of the support plate 29 with the center (rotation axis 20) of the shift cam 26 interposed therebetween.

[0100] The cam portion 33 (driving portion) is formed at two locations different from the meshing portion 32 on the outer peripheral edge of the shift cam 26. The cam portion 33 has a plurality of locking step portions 34 at different distances from the rotation axis 20. The plurality of locking step portions 34 include a first locking step portion 34a, a second locking step portion 34b, a third locking step portion 34c, and a fourth locking step portion 34d.

[0101] In addition, in this embodiment, the first locking step portion 34a, the second locking step portion 34b, the third locking step portion 34c, and the fourth locking step portion 34d are collectively referred to as "locking step portions 34a to 34d".

[0102] The second locking step portion 34b is formed at a position farther from the rotation axis 20 than the first locking step portion 34a. The third locking step portion 34c is formed at a position farther from the rotation axis 20 than the second locking step portion 34b. The fourth locking step portion 34d is formed at a position farther from the rotation axis 20 than the third locking step portion 34c. The locking step portions 34a to 34d can be locked with the contact member 25.

[0103] In the state where the contact member 25 is locked with the first locking step portion 34a (see Figure 3 ), the force of the spring 24 pushing the brake shoe 23 is minimal. Therefore, the brake shoe 23 is allowed to rotate due to the relatively small centrifugal force. Therefore, when the rotation speed of the wheel 103 is relatively low, the brake shoe 23 abuts against the inner peripheral surface of the brake drum 11 to exert braking force.

[0104] When the contact member 25 is locked with the second locking step 34b, the force of the spring 24 pressing the brake shoe 23 is slightly larger than that when the contact member 25 is locked with the first locking step 34a. Therefore, the brake shoe 23 is allowed to rotate when subjected to a large centrifugal force. Therefore, when the rotation speed of the wheel 103 is relatively high, the brake shoe 23 contacts the inner peripheral surface of the brake drum 11 to exert a braking force.

[0105] When the contact member 25 is engaged with the third engagement step 34c, the force of the spring 24 pressing the brake shoe 23 becomes greater. Therefore, the braking force is exerted when the rotation speed of the wheel 103 is higher than when the contact member 25 is engaged with the second engagement step 34b.

[0106] When the contact member 25 is engaged with the fourth engagement step 34d, the force of the spring 24 pressing the brake shoe 23 becomes greater. Therefore, the braking force is exerted when the rotation speed of the wheel 103 is higher than when the contact member 25 is engaged with the third engagement step 34c.

[0107] The locking step portions 34a to 34d are arranged along the circumferential direction around the center (rotation axis 20) of the shift cam 26, and are arranged in this order in the circumferential direction. Therefore, the cam portion 33 can select the locking step portions 34a to 34d according to the rotation position of the shift cam 26 to increase or decrease the force of the pressing spring 24. The two cam portions 33 are arranged in a manner opposite to each other in the radial direction of the support plate 29 with the center (rotation axis 20) of the shift cam 26 sandwiched therebetween.

[0108] The adjustment gear 27 has a plurality of teeth 27a that mesh with the meshing portion 32 of the shift cam 26. The adjustment gear 27 is rotatably supported on the support plate 29. An engagement hole that can be engaged with a rotating tool such as a hexagonal wrench is provided in the adjustment gear 27. The adjustment gear 27 can transmit a force input from the outside to the cam portion 33 by means of the rotating tool engaged with the engagement hole.

[0109] Thus, the adjustment gear 27 can rotate the shift cam 26 relative to the support plate 29. The adjustment gear 27 is operated (rotated) by external input, thereby rotating the shift cam 26, determining the rotation position of the shift cam 26, and adjusting the force of the abutment member 25 pressing the spring 24. The two adjustment gears 27 are arranged in a manner opposite to each other in the radial direction of the support plate 29 with the center (rotation axis 20) of the support plate 29 sandwiched therebetween.

[0110] The shift cam 26 has an outer diameter (diameter of the shift cam) D1 as the maximum outer diameter. The outer diameter D1 is the outer diameter of the meshing portion 32. The adjustment gear 27 has an outer diameter (diameter of the adjustment gear) D2 as the maximum outer diameter. Thus, the outer diameter D1 of the shift cam 26 is larger than the outer diameter D2 of the adjustment gear 27. Therefore, D1>D2 holds.

[0111] In addition, the ratio (D1 / D2) of D1 to D2 is preferably equal to or greater than 3. When the ratio (D1 / D2) of D1 to D2 is within this range, the adjustment range of the braking force (Brake force) can be increased.

[0112] The ratio of D1 to D2 (D1 / D2) can be set to, for example, 10 or less. When the ratio of D1 to D2 (D1 / D2) is within this range, the size of the shift cam 26 can be suppressed. Therefore, the size of the speed control device 1 can be suppressed.

[0113] like Figure 2 and Figure 4 As shown, the cover plate 28 is formed in a disk shape and is arranged at a position further outward in the vehicle width direction than the support plate 29. Figure 2 and Figure 5 As shown, the cover plate 28 is integrated with the support plate 29 in a state of covering the entire centrifugal brake unit 13 .

[0114] In addition, Figure 5 In the figure, the illustration of the cover plate 28 is simplified, and only a part is shown. Figure 6 to Figure 8 Same here.

[0115] The cover plate 28 has a color different from that of the shift cam 26. For example, the cover plate 28 has a color different in brightness from that of the shift cam 26. For example, the cover plate 28 has a color darker than that of the shift cam 26.

[0116] like Figure 4 and Figure 5 As shown, a plurality of windows 40 are formed in the cover plate 28. The window 40 is formed to penetrate the cover plate 28 in the thickness direction. The plurality of windows 40 include a first window 40a, a second window 40b, a third window 40c, and a fourth window 40d.

[0117] In addition, in this embodiment, the first window portion 40a, the second window portion 40b, the third window portion 40c, and the fourth window portion 40d are collectively referred to as "window portions 40a to 40d".

[0118] The windows 40a to 40d are arranged along the circumferential direction of the support plate 29. Thus, the windows 40a to 40d are formed in a manner that they are arranged at different positions along the rotation direction of the shift cam 26. Furthermore, the windows 40a to 40d are arranged in this order in the circumferential direction of the support plate 29, and are arranged at intervals in the circumferential direction of the support plate 29. The windows 40a to 40d are provided so as to be visually recognized from the outside through the opening 19 formed in the second wheel plate 70 and the operation window 11c formed in the brake drum 11 by removing the cover 15 (refer to FIG. Figure 2 ).

[0119] The shapes of the windows 40a to 40d are, for example, circular. The sizes (for example, inner diameters) of the windows 40a to 40d may be the same as or different from each other. The sizes (for example, inner diameters) of the windows 40a to 40d may increase or decrease in this order.

[0120] Figure 5 The state in which the contact member 25 is locked with the first locking step portion 34a is shown. In this state, the shift cam 26 is arranged at a position overlapping with all of the four window portions 40a to 40d. That is, the shift cam 26 is arranged at a position including all of the four window portions 40a to 40d when viewed in a plan view. Therefore, the shift cam 26 can be visually recognized through the four window portions 40a to 40d. The cover plate 28 has a color different from that of the shift cam 26, so the shift cam 26 can be easily visually recognized through the window portion 40a.

[0121] Figure 6 The state in which the contact member 25 is locked with the second locking step portion 34b by operating the adjustment gear 27 and rotating the shift cam 26 is shown. In this state, the shift cam 26 is arranged at a position overlapping with three of the four windows 40a to 40d. Therefore, the shift cam 26 can be visually recognized through the three windows 40b to 40d.

[0122] Figure 7 The figure shows a state where the contact member 25 is locked with the third locking step portion 34c by operating the adjustment gear 27 and rotating the shift cam 26. In this state, the shift cam 26 is arranged at a position overlapping with two window portions 40c and 40d among the four window portions 40a to 40d. Therefore, the shift cam 26 can be visually recognized through the two window portions 40c and 40d.

[0123] Figure 8 The state in which the contact member 25 is locked with the fourth locking step portion 34d by operating the adjustment gear 27 and rotating the shift cam 26 is shown. In this state, the shift cam 26 is arranged at a position overlapping with one window portion 40d among the four window portions 40a to 40d. Therefore, the shift cam 26 can be visually recognized through the one window portion 40d.

[0124] like Figures 5 to 8 As shown, the number of windows 40 that can visually recognize the shift cam 26 varies depending on the rotational position of the shift cam 26 . Therefore, the window 40 can display the rotational position of the shift cam 26 .

[0125] like Figure 3As shown, the support plate 29 is set to, for example, a circular shape, and supports the brake shoe 23 so that it can rotate freely. Moreover, the support plate 29 supports the shift cam 26 and the adjustment gear 27 so that they can rotate freely. In addition, a second sun gear (not shown) protruding toward the inner side in the vehicle width direction is formed on the support plate 29. As described above, the plurality of (3) second planetary gears 121 constituting the second-stage gear mechanism 120 mesh with the second sun gear. Thus, as Figure 2 As shown, the two-stage planetary gear mechanism 80 is configured to transmit the rotational force of the wheel 50 to the support plate 29 .

[0126] (Function of speed control device)

[0127] Next, an example of the operation of the speed control device 1 configured as described above will be described.

[0128] like Figure 1 As shown, when the operating unit 104 of the walking vehicle 101 is pushed by the user, the wheel 103 rotates, and the walking vehicle 101 moves. When the wheel 103 rotates, the rotational force is transmitted to the support plate 29 of the centrifugal brake unit 13. As a result, the support plate 29 rotates around the rotation axis 20 of the axle 21 (see Figure 3 ).

[0129] When the rotation speed of the wheel 103 is lower than or equal to a predetermined speed, the rotation speed of the support plate 29 is also low. Therefore, the brake shoe 23 does not contact the inner peripheral surface of the brake drum 11, and the braking force of the centrifugal brake is suppressed to be low.

[0130] On the other hand, when the rotation speed of the wheel 103 exceeds a predetermined speed, the support plate 29 rotates at a high speed. Therefore, the brake shoe 23 overcomes the elastic force of the spring 24 by centrifugal force, and elastically deforms the spring 24 in a compressed manner while rotating around the rotation axis 31. As a result, the pad 30 of the brake shoe 23 can be pressed against the inner peripheral surface of the brake drum 11. Therefore, the braking force of the centrifugal brake can be increased, and the speed of the wheel 103 can be reduced.

[0131] like Figure 2 As shown, when changing the rotation speed of the wheel 103 in which the centrifugal brake is actuated, the cover 15 is removed from the second wheel plate 70 .

[0132] Next, use a rotating tool such as a hex wrench to Figure 3 By rotating the shift cam 26 using the adjustment gear 27, it is possible to select the locking step portion 34 (34a to 34d) (see Figures 5 to 8 ). Thus, the force of the contact member 25 pressing the spring 24 can be adjusted, and the braking force of the centrifugal brake can be determined.

[0133] [Effects of the speed control device according to the embodiment]

[0134] In the speed control device 1, if Figure 3 As shown, the outer diameter D1 of the shift cam 26 is larger than the outer diameter D2 of the adjustment gear 27. Since the outer diameter D1 of the shift cam 26 is larger, the outer periphery of the shift cam 26 can be ensured to be longer. Therefore, for example, the difference in the distance between the multiple locking step portions 34 (34a~34d) of the shift cam 26 and the rotation axis 20 can be increased, and the adjustment range of the braking force (Brake force) can be increased. In addition, the number of locking step portions 34 can be increased, and the degree of freedom in setting the braking force can be increased. Therefore, for example, it is possible to set the braking force to act when traveling at a higher speed than before.

[0135] In the speed control device 1, the window portion 40 for displaying the rotational position of the shift cam 26 is formed on the cover plate 28, so that the braking force of the centrifugal brake can be displayed easily. Therefore, the rotational speed of the wheel 103 for the centrifugal brake operation can be easily set.

[0136] In the speed control device 1 , the number of the window portions 40 overlapping the shift cam 26 changes according to the rotational position of the shift cam 26 , and therefore the braking force of the centrifugal brake can be displayed in an easily visible manner.

[0137] The walking vehicle 101 is provided with the speed control device 1, so that the adjustment range of the braking force can be increased. Therefore, the degree of freedom in setting the braking force can be increased. Thus, for example, it is possible to set the braking force to act when traveling at a higher speed than before.

[0138] (Second embodiment)

[0139] [Speed ​​Suppression Device]

[0140] Fig. 9 It is a partial plan view of the speed control device 201 according to the second embodiment. Figure 10 to Figure 13 It is a partial plan view of the speed control device 201 . Fig.14 It is a plan view of a portion of the shift cam 226 .

[0141] In this embodiment, the speed control device 1 of the first embodiment (see Figure 3 ) are common structures of the same structure and are marked with the same figure marks and the description is omitted.

[0142] like Fig. 9 As shown, the outer diameter D201 of the shift cam 226 is larger than the outer diameter D202 of the adjustment gear 27 .

[0143] In the speed control device 201, a plurality of position marks 241 are formed on the surface of the shift cam 226 of the centrifugal brake unit 213. The position mark 241 indicates the rotational position of the shift cam 226. The plurality of position marks 241 are formed in a manner of being arranged at different positions along the rotational direction of the shift cam 226. The position marks 241 are represented, for example, by numbers. The plurality of position marks 241 include position marks 241a to 241d. In the present embodiment, the position marks 241a to 241d are represented as "4", "3", "2", and "1" as different numbers, respectively.

[0144] like Fig.10 As shown, a window portion 240 is formed in the cover plate 228 .

[0145] Fig.10 Indicates that the abutment member 25 and Fig. 9 The first locking step portion 34a is shown in a locked state. In this state, the window portion 240 is arranged at a position overlapping the position mark 241a. Therefore, the position mark 241a can be visually recognized through the window portion 240. Fig.11 The adjustment gear 27 is operated to rotate the shift cam 226 so that the contact member 25 and the Fig. 9 The second locking step portion 34b is shown in a locked state. In this state, the position mark 241b can be visually recognized through the window portion 240.

[0146] Fig.12 The adjustment gear 27 is operated to rotate the shift cam 226 so that the contact member 25 and the Fig. 9 The third locking step portion 34 c is shown in a locked state. In this state, the position mark 241 c can be visually recognized through the window portion 240 . Fig.13 The adjustment gear 27 is operated to rotate the shift cam 226 so that the contact member 25 and the Fig. 9 The fourth locking step portion 34d is shown in a locked state. In this state, the position mark 241d can be visually recognized through the window portion 240.

[0147] like Figure 10 to Figure 13 As shown, the position mark 241 that can be visually recognized is different due to the different rotational positions of the shift cam 226. Therefore, the window portion 240 can display the rotational position of the shift cam 226.

[0148] like Fig.14 As shown, the portion of the outer peripheral edge of the shift cam 226 located between the adjacent locking step portions 34 has a first portion 242 and a second portion 243. The first portion 242 and the second portion 243 are, for example, linear (straight) shapes.

[0149] Of the first portion 242 and the second portion 243 formed between the nth locking step portion 34 (n is an integer greater than or equal to 1) and the n+1th locking step portion 34, the first portion 242 is formed so as to be connected to the nth locking step portion 34. The second portion 243 is formed so as to be connected to the n+1th locking step portion 34. Therefore, the second portion 243 is closer to the n+1th locking step portion 34 than the first portion 242. The second portion 243 has a larger inclination angle with respect to the radial direction of the shift cam 226 than the first portion 242.

[0150] [Effects of the speed control device according to the embodiment]

[0151] In the speed control device 201, if Fig. 9 As shown, the outer diameter D201 of the shift cam 226 is larger than the outer diameter D202 of the adjustment gear 27. Therefore, the adjustment range of the braking force can be increased in the same manner as the speed control device 1 of the first embodiment. Therefore, the degree of freedom in setting the braking force can be increased. Therefore, for example, a setting can be made such that the braking force is activated during high-speed driving.

[0152] In the speed control device 201, the window 240 for displaying the rotational position of the shift cam 226 is formed on the cover plate 228, so that the braking force of the centrifugal brake can be displayed easily. Therefore, the setting of the rotational speed of the wheel 103 for the centrifugal brake is easy.

[0153] In the speed control device 201, the window 240 can display the position mark 241, so the braking force of the centrifugal brake can be displayed in an easily understandable manner. In the speed control device 201, the number of the window 240 can be reduced, which is advantageous in achieving miniaturization of the device.

[0154] In the speed control device 201, if Fig.14 As shown, a first portion 242 and a second portion 243 having a large inclination angle are formed between the nth locking step portion 34 (n is an integer greater than 1) and the n+1th locking step portion 34. Therefore, when the contact member 25 is transferred from the nth locking step portion 34 to the n+1th locking step portion 34, a radial movement distance can be ensured at the first portion 242 where the load from the spring 24 is small. Therefore, at the second portion 243 where the load from the spring 24 becomes large, the contact member 25 can be transferred to the n+1th locking step portion 34 with a relatively low force. Therefore, the operation of transferring the contact member 25 from the nth locking step portion 34 to the n+1th locking step portion 34 becomes easy.

[0155] The embodiments of the present invention are described above, but the various structures and their combinations in the embodiments are examples, and addition, omission, substitution, and other changes of structures can be made within the scope of the present invention. The present invention is not limited to the embodiments.

[0156] For example, in the speed control device 1, 201 of the above-mentioned embodiment, the spring 24 (coil spring) is used as the elastic member, but the elastic member is not limited to its structure as long as it can apply force to the brake shoe to the outside. The shape of the window portion is not particularly limited. The shape of the window portion may also be a polygonal shape such as a rectangular shape, an elliptical shape, etc. The number of brake shoes may be one or more (any number more than two).

[0157] In the speed control devices 1 and 201 of the above embodiments, the planetary gear mechanism 80 has a two-stage structure including the first-stage gear mechanism 110 and the second-stage gear mechanism 120 . However, the present invention is not limited to this and may have a one-stage structure.

[0158] In the speed control device 1, 201 of the above-mentioned embodiment, the case where the wheel 50 is formed by combining the first wheel plate 60 and the second wheel plate 70 is cited as an example for description. In the speed control device 1, 201 of the above-mentioned embodiment, the case where the speed control device 1, 201 is arranged in the internal storage space R formed by the first storage space R1 of the first wheel plate 60 and the second storage space of the second wheel plate 70 is cited as an example for description.

[0159] However, the present invention is not limited to these cases. For example, the wheel 103 may be configured by combining a single wheel and a speed control device. An example of this case will be described below as a modified example.

[0160] (Variation Example)

[0161] like Figure 15 to Figure 17 As shown, the wheel 103 includes a wheel structure 17 and a tire 18 which are equivalent to a single wheel. Fig.15 The axle 21 is omitted in the figure.

[0162] The wheel structure 17 includes a rim 251 and a disc 252. The rim 251 is formed in a cylindrical shape. The tire 18 is mounted on the rim 251. The disc 252 includes a mounting portion 253 and a plurality of spokes 254.

[0163] also, Fig.16 It is a six-sided diagram of the wheel 103. Fig.16 (A) shown is a front view of the wheel 103. Fig.16 (B) is a left side view of the wheel 103. Fig.16(C) shown is a right side view of the wheel 103. Fig.16 (D) is a top view of the wheel 103 . Fig.16 (E) is a bottom view of the wheel 103. Fig.16 (F) is a rear view of the wheel 103. Fig.17 It is a perspective view of the wheel 103 .

[0164] For example, the mounting portion 253 is mounted on a wheel hub (not shown). The mounting portion 253 is located at the center of the wheel 103 when viewed from a direction parallel to the rotation axis 20. A plurality of spokes 254 extend radially from the mounting portion 253 to the rim 251. The spokes 254 connect the mounting portion 253 and the rim 251.

[0165] The number of spokes 254 is, for example, any number greater than or equal to 3. When viewed in a direction parallel to the rotation axis 20 , the width of the spokes 254 gradually decreases toward the radially outer side.

[0166] like Fig.15 As shown, the speed control device 250 in this case includes a brake drum 11, a housing 12, a centrifugal brake unit 13, a planetary gear mechanism 14, and a cover 15. The planetary gear mechanism 14 is a one-stage structure.

[0167] The brake drum 11 includes a cylindrical portion 11A. The brake drum 11 is fixed to the end of an axle (not shown). The housing 12 is cylindrical. The housing 12 is attached to one end of the brake drum 11. The cover 15 is detachably attached to the outer surface of the wheel structure 17.

[0168] The centrifugal brake unit 13 is provided inside the cylindrical portion 11A of the brake drum 11. The centrifugal brake unit 13 is a mechanism for generating a braking force (Brake force) of a centrifugal brake between the centrifugal brake unit 13 and the brake drum 11. The centrifugal brake unit 13 is rotatable around a rotation axis 20.

[0169] The wheel structure 17 is rotatable about the rotation axis 20. Therefore, when the wheel structure 17 rotates, the rotational force is transmitted to the centrifugal brake unit 13 via the planetary gear mechanism 14. The wheel structure 17 is formed with an opening 19 through which the window 40 of the cover plate 28 can be visually recognized.

[0170] Even in the case of the wheel 103 and the speed control device 250 configured in this way, the same effects as those of the above-described embodiment can be achieved.

Claims

1. A speed control device, which is provided on a wheel rotating about a rotation axis and controls the rotation speed of the wheel, wherein: The speed control device comprises: Brake drum; a brake shoe for reducing the rotation speed of the wheel by utilizing a braking force generated by contact with the inner peripheral surface of the brake drum; an elastic member having one end and another end, and applying force to the brake shoe by means of the one end; an abutment member provided to the other end portion of the elastic member; a shift cam configured to be rotatable about the rotation axis and to increase or decrease the force with which the abutment member presses the elastic member according to a rotation position; as well as an adjusting gear which is operated by an external input, thereby rotating the shift cam, determining the rotational position of the shift cam, and adjusting the force pressing the elastic member, The shift cam has a diameter greater than a diameter of the adjustment gear.

2. The speed control device according to claim 1, wherein: The speed control device further includes a cover plate covering at least the shift cam. At least one window portion for displaying a rotational position of the shift cam is formed on the cover plate.

3. The speed control device according to claim 2, wherein: The window portion is formed with a plurality of The plurality of window portions are formed so as to be arranged at different positions along the rotation direction of the shift cam. The number of the window portions overlapping the shift cam varies according to the rotational position of the shift cam.

4. The speed control device according to claim 2, wherein: The shift cam is provided with a position mark indicating a rotation position of the shift cam. The window portion is formed so that the position mark can be visually recognized.

5. A vehicle comprising: The speed control device according to any one of claims 1 to 4; and A wheel is provided with the speed suppression device.

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