CN210338167U

CN210338167U - Pedal for balance car and balance car

Info

Publication number: CN210338167U
Application number: CN201921350284.1U
Authority: CN
Inventors: 臧传美
Original assignee: Zhejiang Aerlang Technology Co Ltd
Current assignee: Zhejiang Aerlang Technology Co Ltd
Priority date: 2019-08-20
Filing date: 2019-08-20
Publication date: 2020-04-17
Anticipated expiration: 2029-08-20

Abstract

The utility model discloses a footboard and balance car for balance car, wherein footboard for balance car, including panel and base plate, the panel includes panel body, erection column, anticreep portion, and the lower surface of panel body is connected with the top of erection column, and anticreep portion is connected to the bottom of erection column, the erection column inserts in the through-hole of seting up on the base plate one, anticreep portion laminates and makes panel and base plate looks fixed connection in the base plate lower surface, panel integrated into one piece, the lower surface of base plate is equipped with the convex touch-control portion that is used for triggering sensor on the balance car downwards. The utility model discloses a balance automobile-used footboard comprises panel and base plate, and the panel is moulded plastics on the base plate or the base plate is moulded plastics on the panel, and anticreep portion laminates in the base plate lower surface for footboard compact structure, convenient to use need not sticky, and firmly reliable. The balance car adopts the pedal, so that the installation is convenient, and the service life is prolonged.

Description

Pedal for balance car and balance car

Technical Field

The utility model relates to a footboard and balance car for balance car.

Background

On present balance car, its footboard is various, needs the manual work equipment, and some still need use modes such as sticky fixed, and the footboard after the equipment easily drops, is unfavorable for long-term the use, and then influences the performance of balance car.

SUMMERY OF THE UTILITY MODEL

The utility model relates to a footboard and balance car for the balance car, footboard for the balance car are a non-detachable whole, compact structure, need not sticky, and convenient to use.

The utility model discloses a realize through following technical scheme:

the utility model provides a footboard for balance car, includes panel and base plate, the panel includes panel body, erection column, anticreep portion, and the lower surface of panel body is connected with the top of erection column, and anticreep portion is connected to the bottom of erection column, the erection column inserts in the through-hole of seting up on the base plate is one, anticreep portion laminates and makes panel and base plate looks fixed connection in the base plate lower surface, panel integrated into one piece, the lower surface of base plate is equipped with the convex touch-control portion that is used for triggering sensor on the balance car downwards.

Through adopting above-mentioned technical scheme, the footboard comprises panel and base plate, adopts the secondary technology of moulding plastics, and the panel is moulded plastics on the base plate or the base plate is moulded plastics on the panel, and anticreep portion laminates in the base plate lower surface for footboard compact structure, convenient to use need not sticky, and firm reliable. The touch control part is arranged on the lower surface of the base plate in an integrated mode, the touch control part on the lower surface of the base plate can directly trigger the sensor, other parts do not need to be arranged, only the pedal needs to be installed on the balance car, and the pedal is ingenious in structure and compact.

As a further improvement of the present invention, a first engaging portion is provided on the panel, a third engaging portion is provided on the substrate and engages with the first engaging portion, and the first engaging portion is a through hole, a groove or a protrusion. Through adopting above-mentioned technical scheme, the setting of gomphosis portion one and gomphosis portion three is favorable to the inseparable laminating of panel and base plate.

As a further improvement, the outer fringe of panel body has the downward convex first protruding edge of round, and in the within range that first protruding edge encloses, the lower surface of panel body still was equipped with the downward convex second protruding edge of round. Through adopting above-mentioned technical scheme, the installation of footboard is favorable to in the setting on first protruding edge and the protruding edge of second, when making the footboard install on the frame of balance car, is difficult for producing lateral shifting, is favorable to the accurate trigger sensor of touch-control portion on the footboard.

As a further improvement, the convex edge of second is in the junction with the panel body the second is protruding to be equipped with gomphosis portion two along, the outer fringe of base plate is equipped with the gomphosis portion four with gomphosis portion two phase match gomphosis, gomphosis portion two is through-hole or recess or arch. Through adopting above-mentioned technical scheme, the setting of gomphosis portion two and gomphosis portion four further makes the close laminating of panel and base plate, inseparable.

As a further improvement of the utility model, the anti-disengaging part is flat, and the upper surface of the anti-disengaging part is a plane. Through adopting above-mentioned technical scheme for footboard compact structure does not occupy extra space, and processing is also convenient.

As a further improvement of the present invention, the touch portion is flat. Through adopting above-mentioned technical scheme, touch-control portion is the lamellar structure of platykurtic, can cooperate with the sensor, is favorable to triggering the sensor. For the photoelectric switch as the sensor, the flat touch control part can effectively shield the light beam and skillfully trigger the sensor in the moving process.

As a further improvement of the utility model, the periphery of touch-control portion be provided with spacing one of elastic component on the base plate. Through adopting above-mentioned technical scheme, the spacing portion one of elastic component can be used to spacing and the direction to the elastic component.

As a further improvement of the utility model, the lower surface of the base plate is provided with a clamping part protruding downwards. Through adopting above-mentioned technical scheme, the setting of buckle portion is favorable to base plate and frame to carry out the buckle formula installation, also is difficult for droing when the installation is convenient. The structure of the fastening part can be various, and the bottom of the fastening part can adopt a hook-shaped hook or an outward extending flange.

The balance car comprises the pedal for the balance car, and further comprises an elastic part, a car frame, a circuit board and a sensor, wherein the pedal is installed on the car frame, the elastic part is located between the car frame and a base plate, the upper end of the elastic part is connected with or abutted against the base plate, the lower end of the elastic part is connected with or abutted against the car frame, the sensor is installed on the circuit board, the circuit board is installed on the lower surface of the car frame, a first through hole for the touch part on the base plate to move is formed in the car frame, and the sensor is located below the touch part. Through adopting above-mentioned technical scheme, the balance car adopts this kind of footboard, and the installation is convenient, footboard life extension. The touch control part can trigger the sensor, so that the balance car has corresponding functions, the sensor can be used for sensing whether the balance car carries people, and the elastic piece can timely restore the pedal to an initial state when no people step on the balance car.

As a further improvement of the utility model, the upper surfaces of the left and right sides of the frame are provided with pedal mounting areas for mounting pedals, the edge of each pedal mounting area is provided with a circle of concave grooves, a circle of upward convex third convex edge is arranged in the range enclosed by each groove, and the range enclosed by the third convex edge is provided with a second elastic part limiting part; the frame is also provided with a third through hole for the buckling of the buckling part on the substrate. Through adopting above-mentioned technical scheme, the setting of third protruding edge and recess on the frame is favorable to the installation of footboard, makes the difficult lateral shifting that produces of footboard. The arrangement of the second limit elastic part is beneficial to limiting and guiding the elastic part.

The utility model discloses beneficial effect for prior art has at least: for the pedal, on one hand, the pedal is compact in structure, manual assembly is not needed, the pedal and the pedal are not needed to be bonded by glue, the pedal is simple and ingenious in structure, the pedal is convenient to process, the cost is reduced, and the pedal is convenient to popularize and apply in a large range; for the balance car, the whole car structure is more reasonable, the structure is simpler and more compact, the control performance is also improved, and the service life is also prolonged.

In order to make the aforementioned and other objects, features and advantages of the present invention comprehensible, preferred embodiments accompanied with figures are described in detail below.

Drawings

Fig. 1 is an exploded schematic view of a pedal for a balance car provided in embodiment 1 of the present invention;

FIG. 2 is a schematic structural view of a panel of the pedal for the balance car of FIG. 1;

FIG. 3 is a schematic view of another angle of the panel of FIG. 2;

FIG. 4 is a schematic view, partially in cross-section, of a face plate of the balance car pedal of FIG. 1;

FIG. 5 is a schematic view of another angle of the faceplate of FIG. 4;

FIG. 6 is a schematic structural diagram of a base plate of the pedal for the balance car in FIG. 1;

FIG. 7 is a schematic view of another angle of the substrate shown in FIG. 6;

fig. 8 is a schematic diagram of an explosion structure of the balance car provided in embodiment 2 of the present invention (wheels, direction control levers, batteries, etc. are not shown);

FIG. 9 is a schematic view of a portion of the structure of FIG. 8;

fig. 10 is another angle structure diagram of the balance car in fig. 8.

In the figure: the pedal 1, the panel 11, the panel body 110, the first engaging portion 111, the anti-disengaging portion 112, the second engaging portion 113, the mounting post 114, the first protruding edge 115, the first protruding edge 116, the friction portion 117, the base plate 12, the third engaging portion 121, the first through hole 122, the second engaging portion 113, the fastening portion 124, the touch portion 125, the first elastic element limiting portion 126, the elastic element 2, the frame 3, the threaded hole 31, the third through hole 32, the second elastic element limiting portion 33, the partition plate 34, the bottom plate 35, the first through hole 351, the second through hole 352, the fourth protruding edge 36, the third protruding edge 37, the groove 38, the circuit board 4, the photoelectric switch 41, the wiring port 42, and the fastening member 5.

Detailed Description

To further illustrate the technical means and effects of the present invention adopted to achieve the objects of the present invention, the following buckling drawings and preferred embodiments are described in detail below with reference to the following detailed description of the embodiments, structures, features and effects of the present invention.

In the description of the present application, it is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", "inner", "outer", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are only for convenience in describing the present application and simplifying the description, and do not indicate or imply that the device or element being referred to must be provided with a particular orientation, constructed and operated in a particular orientation, and thus, should not be construed as limiting the present application.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present application, "a plurality" means two or more unless specifically limited otherwise.

In this application, unless expressly stated or limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can include, for example, fixed connections, removable connections, or integral connections; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as appropriate.

Example 1

A pedal for a balance car is shown in figure 1, the pedal 1 comprises a panel 11 made of soft materials and a base plate 12 made of hard materials, the panel 11 is installed on the base plate 12, the pedal adopts a secondary injection molding process, the base plate 12 is firstly injection molded, and then the panel 11 is injection molded on the basis of the base plate 12.

Referring to fig. 1 to 5, the panel 11 is integrally formed, and includes a panel body 110, a first convex edge 115, a second convex edge 116, a mounting post 114 and an anti-slip portion 112, wherein a circle of first convex edge 115 protruding downward is connected to an outer edge of the panel body 110, a circle of second convex edge 116 protruding downward is further connected to a lower surface of the pedal body 110, a gap is formed between the first convex edge 115 and the second convex edge 116, in a space surrounded by the second convex edge 116, the lower surface of the pedal body 110 is connected to a plurality of mounting posts 114 extending downward, and the bottom of each mounting post 114 is connected to the anti-slip portion 112. The mounting post is at least one. The mounting posts 114 may be located at each corner of the panel body 110, at a middle position of each edge of the panel body, and at a central position of the panel body, so that the panel 11 is securely mounted on the substrate 12 in all directions. The retaining portion 112 extends in a flat shape toward the radial outer periphery of the mounting post 114, and the upper surface and the lower surface of the retaining portion 112 may be flat.

The panel body 110 is provided with a first embedding part 111, the first embedding part 111 is a strip-shaped through hole or a groove or a bulge, the second convex edge 116 is provided with a second embedding part 113 at the joint of the second convex edge 116 and the panel body 110, and the second embedding part 113 is a strip-shaped through hole or a groove or a bulge.

The upper surface of the panel body 110 is provided with a plurality of friction portions 117, as shown in fig. 2, each friction portion 117 protrudes upward from the upper surface of the pedal and is in a strip shape and a flat shape, and the length direction of each friction portion 117 points to the left front corner of the pedal, that is, each friction portion 117 is radially arranged with the left front corner of the pedal as the center. An arrow indicating the front-rear direction is provided at the front left corner of the pedal. In this embodiment, the pedal shown in fig. 2 is a right pedal of the balance car, and for a left pedal, the characteristics of the friction portion on the left pedal are symmetrically arranged on the right pedal, as shown in fig. 8, and are not described again. In other embodiments, the friction portion 117 may be provided as a groove-like feature recessed downward relative to the upper surface of the tread. The first engaging portion 111 may be disposed at the position of the friction portion 117.

As shown in fig. 6 and 7, the substrate 12 is provided with a third engaging portion 121, the third engaging portion 121 is matched with the first engaging portion 111 in shape, if the first engaging portion 111 is a long strip-shaped through hole or a groove, the third engaging portion 121 is a long strip-shaped protrusion, and if the first engaging portion 111 is a long strip-shaped protrusion, the third engaging portion 121 is a long strip-shaped through hole or a groove. Of course, the shape may be various and is not limited to the elongated shape. The edge of the substrate 12 is provided with a fitting portion four 123 that matches the fitting portion two 113. The base plate 12 is further provided with a first through hole 122 for the mounting post 114 to pass through. Each corner position of the lower surface of the base plate 12 is provided with a fastening part 124 protruding downwards, and the bottom of the fastening part 124 is hook-shaped or flange-shaped.

Referring to fig. 7, a flat touch portion 125 protruding downward is disposed near the right of the middle of the lower surface of the substrate 12, and the touch portion 125 is used for triggering a sensor on the balance car. The periphery of the touch portion 125 and the lower surface of the substrate 12 are further provided with a first elastic limiting portion 126 protruding downward, the cross section of the first elastic limiting portion 126 is circular, and the touch portion 125 is located within a circle surrounded by the first elastic limiting portion 126 and is located at a non-central position within the circle. Of course, in other embodiments, the touch portion 125 may not be located within the circle surrounded by the first elastic limiting portion 126. In other embodiments, one of the elastic part limiting parts is an inwardly recessed annular groove, the cross section of the elastic part is also in a circular ring shape, and the elastic part is a spring which is inserted in the annular groove and is convenient for guiding and limiting. Of course, the cross section of the first elastic element limiting part can also be circular, namely the first elastic element limiting part is in a cylindrical shape protruding downwards, and the periphery of the first cylindrical elastic element limiting part can be sleeved with a spring and can also play a role in limiting and guiding. The front side and the rear side of the middle part of the lower surface of the base plate 12 are both provided with guide posts 127 which protrude downwards, threaded holes can be formed in the guide posts 127 for fastening pieces to be screwed in, on one hand, the guide function is achieved, and on the other hand, the pedal 1 can be prevented from falling off from the frame of the balance car. The first elastic element-limiting portion 126 is located between the two guiding posts 127. The lower surface of the base plate 12 is also provided with criss-cross ribs for enhancing the strength of the pedal.

After the second injection molding, the mounting posts 114 are located in the first through holes 122, and the upper surface of the anti-slip portion 112 can be attached to the lower surface of the substrate 12. The first fitting part 111 is fitted with the third fitting part 121, and the second fitting part 113 is fitted with the fourth fitting part 123. The pedal 1 is made of two different materials, but is machined without manual assembly, and the panel 11 and the base plate 12 are not detachable, so that the structure is firm and stable unless manually damaged.

Example 2

A balance car, as shown in fig. 8 to 10, comprises a frame 3, an elastic member 2 and a sensor, and further comprises a pedal 1 as described in embodiment 1. The pedal 1 is arranged on the frame 3, the elastic element 2 is positioned between the frame 3 and the pedal 1, the upper end of the elastic element is connected with or abutted against the base plate 12 of the pedal 1, and the lower end of the elastic element is connected with or abutted against the frame 3. The sensor is mounted on the circuit board 4, the circuit board 4 is mounted below the frame 3 by the fastener 5 (screw), and the sensor on the circuit board 4 is located below the touch portion 125. In other embodiments, the sensor may also be directly mounted on the frame, as long as the sensor is located below the touch portion 125, i.e. in the moving direction of the touch portion, and can be triggered by the touch portion.

The frame 3, as shown in fig. 8, 9 and 10, is an upper shell of the balance car, and pedal mounting areas for mounting pedals are arranged on the left side and the right side of the upper surface of the frame 3. Because the structural characteristics of the pedal mounting areas on the left side and the right side of the frame are consistent, the pedal mounting area on the right side is taken as an example for explanation, referring to fig. 9, a circle of concave groove 38 is arranged at the edge of the pedal mounting area, a circle of convex third edge 37 is arranged in the space surrounded by the groove 38, a circle of convex third edge 37 is arranged on the frame, a space surrounded by the convex third edge 37 is arranged, a second elastic limiting part 33 is arranged on the upper surface of the frame in an upward convex manner, the cross section of the second elastic limiting part 33 is in a circular ring shape, the position of the second elastic limiting part 33 corresponds to the position of the first elastic limiting part 126, the shape characteristics of the second elastic limiting part 33 can also be matched with the first elastic limiting part to limit the elastic part 2, the upper end of the elastic part is connected or abutted against the first elastic limiting part, and the lower end of the elastic part is connected or abutted. The elastic member 2 may be a spring having an outer diameter smaller than the inner diameter of the second elastic member limit part 33. In the circle surrounded by the second elastic element limiting portion 33, a bottom plate 35 for placing a spring is disposed, referring to fig. 9, a first through hole 351 and a second through hole 352 are disposed on the bottom plate 35, the first through hole 351 and the second through hole 352 are both located above the circuit board 4, the first through hole 351 corresponds to the position of the photoelectric switch 41 on the circuit board 4, and the touch portion 125 can conveniently pass through the first through hole 351 from top to bottom and trigger the photoelectric switch. The second through hole 352 corresponds to the position of the wiring port 42 on the circuit board 4, facilitating the wiring of the wiring port. A partition plate 34 is provided between the first through hole 351 and the second through hole 352, and front and rear ends of the partition plate 34 are connected to the bottom plate 35. The bottom plate 35 is further provided with a threaded hole 31 for screwing the fastener 5. In the space surrounded by the third convex edge 37, the four corners of the pedal mounting area are provided with third through holes 32 for the buckling part 124 to be buckled in, and the positions of the third through holes 32 correspond to the positions of the buckling parts. The pedal mounting area is further provided with a fourth through hole 39 for inserting the guide column 127. Criss-cross ribs are also arranged in the pedal mounting area.

Referring to fig. 10, a fourth convex edge 36 protruding downward is disposed on the lower surface of the frame at the position of the pedal mounting area and below the second elastic element limiting portion 33, the fourth convex edge 36 is rectangular frame-shaped, and a notch for passing a wire at the terminal port is formed in a side wall of the fourth convex edge 36. The threaded hole 31 is positioned in the space surrounded by the fourth convex edge.

Referring to fig. 8-10, the outer edge of the circuit board 4 is rectangular in shape and has a dimension slightly larger than or equal to the cross-sectional dimension of the outer wall of the fourth flange 36. An opto-electronic switch 41 (a kind of sensor), a wiring port 42 are mounted on the upper surface of the circuit board 4. The photoelectric switch is a short-term photoelectric proximity switch, and detects whether an object exists or not by using the shielding or reflection of the detected object to a light beam and switching on a circuit through a synchronous circuit.

When the pedal 1 is installed, the pedal 1 is installed in the pedal installation area of the frame 3, specifically, the guide column 127 on the base plate 12 is inserted into the fourth through hole 39, and the fastening portion 124 on the base plate 12 is fastened into the third through hole 32. The first ledge 115 is insertable into the groove 38 and the gap between the first ledge and the second ledge is matable with the third ledge 37, i.e. the third ledge is insertable into the gap. The buckling part 124 is buckled in the third through hole 32, and the hook or the flange at the bottom of the buckling part can effectively prevent the pedal from falling off. One end of the spring is abutted against the first elastic part limiting part 126 on the pedal, the other end of the spring is abutted against the bottom plate 35 in the second elastic part limiting part 33 on the frame, and the end parts of the springs can be prevented from moving on the transverse position by the elastic part limiting parts. The touch portion 125 on the pedal is located above the photoelectric switch 41, i.e. the photoelectric switch 41 is located on the moving path of the touch portion 125.

The circuit board 4 is screwed on the threaded hole 31 in the fourth ledge of the lower surface of the frame 3 by the fastener 5, the upper surface of the circuit board 4 can abut against the lower surface of the fourth ledge, the photoelectric switch 41 on the circuit board 4 is aligned with the first through hole 351, the wiring port 42 is aligned with the second through hole 352, the photoelectric switch 41 and the wiring port 42 are respectively located at two sides of the partition plate 34, and the partition plate 34 can prevent the wires of the wiring port from interfering with the photoelectric switch.

Of course, the complete balance car further comprises wheels, batteries, a control panel, a lower shell, a direction control rod and the like, and the whole balance car is conventional in the field and is not described in detail. During the use, the operator steps on footboard 1, footboard 1 takes place deformation, panel body and base plate 12 can move down integratively, touch-control portion 125 of the lower surface of base plate 12 moves down, touch-control portion 125 can be in photoelectric switch 41's clearance, in order to trigger photoelectric switch, make the corresponding signal of balance car perception, in order to carry out corresponding function, in this embodiment, whether photoelectric switch 41 can stand the function switch on the balance car as the perception has the operator, if it stands on the footboard on the balance car to detect someone, can normally start the balance car, carry out subsequent riding and control, if it stands on the balance car to detect nobody, then can't start the balance car. When the operator leaves the pedal, the elastic member 2 can reset the pedal, so that the touch portion 125 is separated from the photoelectric switch.

The above description is only a preferred embodiment of the present invention, and the present invention is not limited to the above description, and although the present invention has been disclosed by the preferred embodiment, it is not limited to the present invention, and any person skilled in the art can make modifications or changes equivalent to the above embodiments without departing from the scope of the present invention, but all the modifications, changes and modifications of the above embodiments that do not depart from the technical scope of the present invention are within the scope of the present invention.

Claims

1. The utility model provides a footboard for balance car, characterized in that, includes panel (11) and base plate (12), panel (11) are including panel body (110), erection column (114), anticreep portion (112), and the lower surface of panel body (110) is connected with the top of erection column (114), and anticreep portion (112) are connected to the bottom of erection column (114), erection column (114) insert in through-hole (122) seted up on base plate (12), anticreep portion (112) laminate in base plate (12) lower surface messenger panel (11) and base plate (12) looks fixed connection, panel (11) integrated into one piece, the lower surface of base plate (12) is equipped with convex touch-control portion (125) that are used for triggering sensor on the balance car downwards.

2. The pedal for the balance vehicle according to claim 1, wherein the panel (11) is provided with a first engaging portion (111), the substrate (12) is provided with a third engaging portion (121) engaged with the first engaging portion (111), and the first engaging portion (111) is a through hole, a groove or a protrusion.

3. The pedal for the balance vehicle as claimed in claim 1, wherein the outer edge of the panel body (110) has a ring of first protruding edges (115) protruding downward, the first protruding edges (115) enclose a range, and the lower surface of the panel body (110) is further provided with a ring of second protruding edges (116) protruding downward.

4. The pedal for the balance vehicle as claimed in claim 3, wherein a second engaging portion (113) is provided on the second protruding edge (116) at the connection of the second protruding edge (116) and the panel body (110), a fourth engaging portion (123) is provided on the outer edge of the base plate (12) for engaging with the second engaging portion (113), and the second engaging portion (113) is a through hole, a groove or a protrusion.

5. The balance car pedal according to any one of claims 1 to 4, wherein the retaining portion (112) has a flat plate shape, and an upper surface of the retaining portion (112) is a flat surface.

6. The pedal for the balance vehicle according to any one of claims 1 to 4, wherein the touch portion (125) is flat.

7. The pedal for the balance vehicle according to any one of claims 1 to 4, wherein a first elastic member limiting portion (126) is provided on the substrate (12) at the periphery of the touch portion (125).

8. Pedal for balance vehicles according to any one of claims 1 to 4, characterized in that said base plate (12) is provided, on its lower surface, with a downwardly projecting hooking portion (124).

9. Balance car, characterized by, include the footboard for balance car of any one of claims 1-8, still include elastic component (2), frame (3), circuit board (4) and sensor, the footboard is installed on frame (3), elastic component (2) are in between frame (3) and base plate (12), the upper end of elastic component (2) is connected or is leaned on base plate (12), the lower extreme is connected or is leaned on frame (3), the sensor is installed on circuit board (4), circuit board (4) are installed in frame (3) lower surface, offer the first through-hole (351) that supplies the touch-control portion (125) activity on base plate (12) on frame (3), the sensor is located the below of touch-control portion (125).

10. The balance vehicle as claimed in claim 9, wherein the upper surfaces of the left and right sides of the frame (3) are provided with pedal mounting areas for mounting pedals, the edge of each pedal mounting area is provided with a circle of concave grooves (38), a circle of convex edges (37) protruding upwards are arranged in the range enclosed by each groove, and a second elastic element limiting part (33) is arranged in the range enclosed by the convex edges (37); the frame is also provided with a third through hole (32) for the buckling of a buckling part (124) on the base plate (12).