Frame type matched with wheels capable of going upstairs and downstairs and going upstairs and downstairs mode

Abstract

The invention relates to the technical field of upstairs and downstairs functions of electric wheelchairs, wheeled electric trolleys and the like, in particular to a frame type matched with wheels capable of upstairs and downstairs and an upstairs and downstairs mode. A longitudinal main beam of the frame adopts a sliding rail type, wheel frames of front and rear wheels capable of going upstairs and downstairs are respectively connected to inner and outer rails or outer and inner rails of the longitudinal sliding rail main beam, the front and rear wheels are driven by a motor and can be braked, and the front and rear wheels independently and alternately finish the actions of going upstairs and downstairs when going upstairs and downstairs; by means of the mode, the safety of going upstairs and downstairs and the adaptability to the stair size of electric wheelchairs, wheeled electric trolleys and the like can be greatly guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of stair-climbing functions of electric wheelchairs, wheeled electric trolleys and the like, and in particular to a frame type equipped with wheels capable of climbing stairs and a stair-climbing method. Background Art

[0002] With the advancement of technology, the improvement of people's living standards and the increasing severity of aging, the requirements for the stair-going and going-up functions of wheeled vehicles such as electric wheelchairs and unmanned electric logistics vehicles will become higher and higher.

[0003] There are basically no wheeled vehicles such as electric wheelchairs on the market now, which use the wheels themselves to have the function of going up and down stairs to solve the problem of going up and down stairs.

[0004] The electric wheelchairs currently on the market that have the function of going up and down stairs basically have a set of track mechanisms added outside the wheels, which either requires another person to support and operate the wheelchair to go up and down the stairs, or a support mechanism for converting between stairs and flat ground must be added outside the track mechanism; the track mechanism may slide when the stair steps are too smooth or the stairs are steep.

[0005] One of the main applications of logistics wheeled unmanned electric vehicles will be delivering goods and meals to homes. For homes without elevators, they will need to have the ability to go up and down stairs well.

[0006] There are also some robots, such as corridor cleaning robots and nursing robots used in environments with stairs, which have requirements for the function of going up and down stairs.

[0007] From the published patent documents and other materials, we can see many technical solutions for enabling the wheels to have the function of going up and down stairs; the patent application with application number CN202411844018X and publication number CN119548330A also proposed the technical solution of "a flexible auxiliary wheel coaxially parallel to the wheel". When driving on flat ground, its flexible wheel belt similar to the track is retracted around the center of the axle without affecting the movement of the wheel. When going up and down stairs, its flexible wheel belt is stretched out to form a large-diameter flexible wheel that can go up and down stairs. The retracting and extending mechanism of the flexible wheel belt can be directly installed on the wheel, and the battery and controller in the vehicle body provide power drive through an electrical slip ring; with the progress of materials science and technology and other science and technology, I believe that there will be more technical solutions that enable wheels to have excellent functions of going up and down stairs.

[0008] It should be pointed out that lengthening the teeth on the wheels can also enable the wheels to have a certain ability to go up and down stairs, but this will greatly reduce the stability of the wheels when driving on flat ground. Ordinary wheels can also have a certain ability to go up and down stairs under certain conditions (such as increasing the wheel diameter and tire softness).

[0009] For electric wheelchairs, electric wheeled carts and other vehicles with front and rear wheels, the function of going up and down stairs is not enough to rely solely on the wheels having the function of going up and down stairs. For example, when the front and rear wheels have a fixed wheelbase, the front and rear wheels may be on the edge of the stairs at the same time. In this way, whether going up or down the stairs, the entire vehicle may collapse towards the lower stairs, etc. Therefore, other technical links are needed to complete the safe and complete function of going up and down stairs for electric wheelchairs, wheeled electric carts, etc. Summary of the invention

[0010] The present invention aims to propose a technical solution for realizing the stair-going and climbing function of an electric wheelchair, an electric wheeled car and the like with front and rear wheels in combination with wheels having the stair-going and climbing function.

[0011] To this end, the purpose of the present invention is to propose a frame type and a stair-climbing method equipped with wheels that can go up and down stairs, so that electric wheelchairs, electric wheeled vehicles, etc. equipped with wheels that can go up and down stairs have safe and complete stair-climbing functions.

[0012] Technical solution of the present invention The technical solution of the present invention is: the longitudinal main beam of the frame adopts a slide rail type, the wheel frames of the front and rear wheels that can go up and down the stairs are respectively connected to the inner and outer rails or the outer and inner rails of the longitudinal slide rail main beam, and the front and rear wheels are driven by a motor with a reducer and can be braked; the way of going up and down the stairs is that the front and rear wheels complete the going up and down stairs action separately and alternately.

[0013] There are two main ways in which the wheels are driven by motors and can be braked: one is that the motor is equipped with an ordinary gear reducer to drive the wheels and has an electronically controlled braking system, such as an electromagnetic brake; the other is that the motor is equipped with a worm gear reducer with self-locking performance to drive the wheels and brake the wheels.

[0014] In the case of a slide rail frame, the front and rear wheels can go up and down stairs separately and alternately. The basic method is that when the front wheels or rear wheels go up and down stairs, the rear wheels or front wheels are in a braked state on the stair tread (or plane). Under some conditions (such as a long tread), the front wheels or rear wheels can be driven to rotate slowly on the tread (or plane) during the process of going up and down stairs. This method can greatly ensure the safety of going up and down stairs and the adaptability to the size of stairs. Figure 1 , Figure 4 .

[0015] The sliding length of the frame slide rail can be divided into two parts. The first part is the part that needs to increase the wheelbase between the front and rear wheels to ensure that the center of gravity is between the front and rear wheels during going up and down stairs or up and down slopes (if the flexibility of turning on the corner platform of a smaller staircase and walking on flat ground is not considered, this part can be directly considered in the wheelbase of the front and rear wheels before sliding). The second part is the sliding length part that is required to meet the requirements of the alternating going up and down stairs action of the front and rear wheels.

[0016] The sliding length required for the front and rear wheels to alternately go up and down the stairs must take into account the sliding length required for the slide rails when the front and rear wheels respectively stay on the stair treads (when one set of the rear wheels stays on the stair treads, the other set may need to extend the slide rails before it can stop on the treads), plus the sliding length required for the front or rear wheels to complete one up and down stair. The total length of the two may vary depending on the type of wheels that can go up and down stairs; the wheels that can go up and down stairs of the patent application number CN202411844018X and the publication number CN119548330A can be adjusted according to the type of wheels that can go up and down stairs. When climbing stairs, the radius of the wheel is about 4 times the radius r of the minimum radius after the wheel is deformed by force (the sliding distance required for the front and rear wheels to stay on the step surface can be considered as greater than r, and the sliding length required for the front or rear wheel to complete a up and down stair can be considered as greater than 2r). Assuming that the wheel radius is 150mm and the radius of the flexible auxiliary wheel after stretching is 225mm, the minimum radius of the flexible auxiliary wheel after being deformed by force is 150mm (limited by the wheel), the sliding length of the slide rail can be about 600mm. In short, no matter the type of wheel that can go up and down stairs, the longer the sliding length of the slide rail is, the better the adaptability.

[0017] The three-section slide rail composed of an outer rail, a middle rail and an inner rail can have a slide-out length that is more than 1 times the length of the outer rail, which can meet the above-mentioned requirements of stable center of gravity and the requirements of alternating front and rear wheels when going up and down stairs. For example, taking the electric wheelchair with wheels that can go up and down stairs with application number CN202411844018X and publication number CN119548330A as an example, the length of the whole vehicle in the flat ground driving state with the slide rail closed is 1000mm, the wheel diameter is 300mm (after the flexible auxiliary wheel is folded), and the wheelbase of the front and rear wheels is 700mm. The frame slide rail is selected with a closed length of 700mm and a slide-out length of not less than 800mm. The slide-out length that meets the center of gravity stability requirement when going up and down stairs or up and down slopes is 200mm, and the slide-out length that meets the alternating front and rear wheels going up and down stairs is not less than 600mm. The slide-out length of the slide rail is limited to not less than 200mm during the process of going up and down stairs.

[0018] If the requirement of center of gravity stability when going up and down stairs or up and down slopes is directly considered in the wheelbase of the front and rear wheels when the slide rails have not slid out, the length of the electric wheelchair in the closed state of the slide rails in the above example becomes 1200mm and the wheelbase of the front and rear wheels is 900mm. At this time, the two-section slide rail composed of the outer rail and the inner rail can meet the requirements. If the closed length of the slide rail is set to 900mm, the inner rail can slide out to a length of not less than 600mm.

[0019] Applying damping materials such as damping agent in the slide rail can improve the stability of electric wheelchairs and electric wheeled vehicles going up and down stairs.

[0020] When there is not much friction between the rails of the sliding rail frame, the front wheel (and its rails and load) or the rear wheel (and its rails and load) can move downstairs alone ( Figure 4 In the "v" state in the figure), the wheels that can go up and down stairs (such as the flexible auxiliary wheels of the patent application with application number CN202411844018X and publication number CN119548330A) may not have enough adhesion or hooking force with the stairs, and cannot "hang" on the edge of the stairs, and fall to the tread surface of the next stair; in order to make the action of going down the stairs comfortable and smooth, a damping element may be applied to the slide rail, and the damping force of the damping element is proportional to the sliding speed of the slide rail. In this way, when a fall occurs, the damping force will "pull" or "hold" the rapid sliding of the slide rail, playing a role of slowing down; similarly, when the front wheel or the rear wheel completes the action of going up the stairs alone, it may also fail to "flip" up and fall down ( Figure 4 The "i" state in Figure 10 shows the state of the load), and the damping function also has a slowing effect.

[0021] The control of the alternating going up and down stairs action of the front and rear wheels of an electric wheelchair, an electric wheeled trolley, etc. can be divided into three modes: fully manual, semi-automatic, and fully automatic.

[0022] The fully manual method is to set up a separate joystick for each wheel; the semi-automatic method is that when going up or down stairs, the controller limits the joystick to switch between controlling the rotation of the front wheels and controlling the rotation of the rear wheels; the fully automatic method is to use a laser radar that rotates and scans in the vertical direction at the front and rear wheels to obtain the size of the steps and the position of the front and rear wheels on the stairs, and then combine the walking intention (or path setting) of the operating handle and the information from the body angle posture sensor, the slide rail slide length sensor, etc., and the controller automatically completes the control of the alternating going up and down stairs action of the front and rear wheels.

[0023] The U-turn of electric wheelchairs, electric wheeled carts, etc. at the corners of stairs can be completed by the distance information to the surrounding walls detected by the horizontal rotating scanning laser radar installed on the vehicle body, and the controller can assist in controlling the rotation of each wheel in combination with the walking intention or path setting. Beneficial Effects

[0024] This type of frame type and stair-climbing wheels enable electric wheelchairs, electric wheeled vehicles, etc. to have better safety, adaptability to stair size and convenience when going up and down stairs (can go up and down stairs in both forward and reverse directions), and also have a certain ability to overcome obstacles and climb steep slopes; this type of frame type and stair-climbing wheels can also be used as the chassis part of some special-purpose equipment or vehicles, such as corridor cleaning robots, nursing robots that have the requirement of going up and down stairs, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a diagram illustrating the principle of the present invention (the wheels that can go up and down stairs adopt the type of patent application with application number CN202411844018X and publication number CN119548330A, which can be replaced by other technical methods with equivalent functions.) Figure 2 This is a schematic diagram of the structure of a slide rail frame chassis of an electric wheeled trolley according to the first embodiment of the present invention; Figure 3 This is a schematic diagram of the structure of the electric wheelchair slide-type frame chassis and seat part of the second embodiment of the present invention; Figure 4 This is a schematic diagram of the process of the front and rear wheels alternately going up and down stairs in the second embodiment; Figure 5 This is a schematic diagram of the design of a semi-automatic control panel for going up and down stairs in Example 2. Reference numerals

[0026] 100. Stair tread; 101. Stair riser; 102. Stair edge; 200, front wheel; 201, rear wheel; 202, folded state of flexible auxiliary wheels for wheels in parallel for going up and down stairs; 203, unfolded state of flexible auxiliary wheels for wheels in parallel for going up and down stairs; 204, electric retracting and extending mechanism of flexible auxiliary wheels for wheels in parallel; 205, electrical slip ring; 206, wheel limit retaining ring; 207, wheel limit retaining ring top screw; 208, electrical slip ring fixing frame; 300, outer rail of slide rail; 301, ball bearing limit stopper of outer rail of slide rail; 302, ball bearing of slide rail; 303, inner rail of slide rail; 304, ball bearing limit stopper of inner rail of slide rail; 305, middle rail of three-section slide rail; 310. Wheel frame of the front wheel of the electric trolley; 311. The front wheel motor of the electric trolley; 312. The front wheel motor of the electric trolley has a self-locking turbine reducer; 313. The output shaft of the turbine reducer; 314. Wheel frame of the rear wheel of the electric trolley; 315. The rear wheel motor of the electric trolley; 316. The rear wheel motor of the electric trolley has a self-locking turbine reducer; 320. Electric trolley slide rail support frame; 321. Electric wheelchair slide rail support frame; 330. Electric wheelchair front wheel motor; 331. Electric wheelchair front left wheel gear transmission; 332. Electric wheelchair front right wheel gear transmission; 333. Electric wheelchair rear wheel motor; 334. Electric wheelchair rear right wheel gear transmission; 335. Electric wheelchair rear wheel frame; 336. Electromagnetic brake; 337. Electromagnetic brake clutch handle; 340. Support frame for the front wheel of the electric wheelchair that does not occupy the leg space; 341. Support plate for the front wheel motor reducer and telescopic rod of the electric wheelchair; 342. Fixed support frame for the front wheel motor reducer of the electric wheelchair; 343. Front wheel axle of the electric wheelchair; 344. Driving gear of the front wheel of the electric wheelchair; 345. Transmission intermediate gear shaft of the front wheel of the electric wheelchair; 346. Transmission intermediate gear of the front wheel of the electric wheelchair; 347. Driven gear ring of the front wheel of the electric wheelchair; 348. Protection box bottom box of the front wheel transmission gear set of the electric wheelchair; 349. Protection box panel of the front wheel transmission gear set of the electric wheelchair; 34a. Support plate of the seat of the electric wheelchair; 34b. Support plate seat for the electric telescopic rod of the seat of the electric wheelchair; 350. Electric wheelchair seat; 351. Electric telescopic rod of electric wheelchair seat; 352. Connecting seat of electric wheelchair seat and electric telescopic rod; 353. Connecting plate of electric wheelchair seat and frame; 354. Electric wheelchair lifting shaft; 355. Shaft retaining ring; 360. Locking and limiting rod plate of electric trolley slide; 361. Locking and limiting rod plate of electric wheelchair slide; 362. Locking buttonhole of electric trolley slide; 363. Limit stopper of electric trolley slide; 364. Limit block of electric trolley slide; 365. Locking and limiting rod plate front buttonhole of electric wheelchair slide; 366. Locking and limiting rod plate front limit stopper of electric wheelchair slide; 367. Locking and limiting rod plate rear buttonhole of electric wheelchair slide; 368. Locking and limiting rod plate rear limit stopper of electric wheelchair slide; 370, sliding rail locking bolt cover sliding seat; 371, locking bolt cover electric telescopic rod; 372, telescopic rod seat; 373, locking bolt cover; 374, bolt cover and electric telescopic rod connecting seat; 375, bolt rod; 376, bolt rod cap; 377, bolt spring; 378, locking bolt; 380, sliding rail limit lock tongue sleeve sliding seat; 381, limit lock tongue sleeve electric telescopic rod; 382, ​​limit lock tongue sleeve; 383, limit lock tongue; 390. The rear wheels of the electric wheelchair can be opened and limited and locked; 400, screws and nuts; 410. Electric wheelchair controller; 411. Joystick (universal joystick); 412. Power switch; 413. Switch for switching between ground mode and stair mode; 414. Battery indicator; 415. Stairway auxiliary wheel folding indicator; 416. Ground mode indicator; 417. Stairway auxiliary wheel unfolding indicator; 418. Stairway mode indicator; 419. Horn; 41a. Rear wheel position switch button; 41b. Rear wheel backward position indicator; 41c. Rear wheel front position indicator; 41d. Ground speed downshift button; 41e. Ground speed upshift button; 41f. Ground speed gear indicator; 41g. Stairway mode front wheel forward indicator; 41h. Stairway mode front wheel backward indicator; 41i. Stairway mode rear wheel forward indicator; 41j. Stairway mode rear wheel backward indicator; 41k. Front and rear wheel alternate rotation selection button; 41n. Slide rail slide-out length indicator; 420. Vertically rotating scanning laser radar; 421. Horizontally rotating scanning laser radar; 422. Laser radar bracket. DETAILED DESCRIPTION

[0027] The wheels in the embodiment adopt the patent application type with application number CN202411844018X and publication number CN119548330A. They can be replaced by wheels of other technical methods with equivalent functions that can go up and down stairs, and corresponding changes can be made to the sliding length of the slide rails, etc.

[0028] Embodiment 1: This embodiment is a slide rail frame chassis of an electric wheeled trolley, which adopts a two-section slide rail, and the drive and brake of the wheel are an electric motor equipped with a worm gear reducer with self-locking performance.

[0029] The main dimensions of this embodiment are set as follows: the total length of the vehicle body is 900mm (after the flexible auxiliary wheels are folded), the total width of the vehicle body is 600mm - the vehicle body can turn around in a space of 1100mmX1100mm, the wheel diameter is 300mm (after the flexible auxiliary wheels are folded), the front and rear wheel wheelbases in flat ground and uphill driving states and the minimum wheelbases of the front and rear wheels in the upstairs and downhill driving states are both 600mm, the closed length of the slide rail is 900mm, and the slide rail can slide out a length of more than 600mm when the front and rear wheels alternately go up and down stairs.

[0030] The outer rail 300 of the slide rail is fixedly mounted on the slide rail support frame 320, the front wheel frame 310 is fixed on the outer rail 300 of the slide rail, and the rear wheel frame 314 is fixed on the inner rail 303 of the slide rail. Figure 2 .

[0031] The worm gear transmissions 312 and 316 are fixed on the front wheel frame 310 and the rear wheel frame 314, and the output shaft 313 of the worm gear transmission serves as the axle of the front and rear wheels.

[0032] The electrical slip ring fixing frame 208 is fixedly mounted on the front and rear wheel frames 310 and 314, and provides axial limitation for the electrical slip ring 205 and a fixing point for the stator end of the electrical slip ring.

[0033] When the electric trolley is traveling on flat ground or uphill or downhill, it is locked in the closed state of the slide rail, that is, the electric trolley slide rail locking and limit rod plate 360 ​​fixed on the rear wheel support frame 314 cooperates with the locking tongue mechanism and the electric trolley slide rail limit block 364 fixed on the slide rail support frame 320 to complete the locking of the slide rail in the closed state.

[0034] The lock tongue mechanism is composed of a slide rail locking lock tongue sleeve sliding seat 370 fixed on the slide rail support frame 320, a lock tongue sleeve 373 that can slide on the lock tongue sleeve sliding seat 370, and a locking lock tongue 378 that slides in the lock tongue sleeve 373; wherein the connection between the lock tongue 378 and the lock tongue rod 375 is a screw connection, and the lock tongue 378 is provided with a screw through hole connected to the lock tongue rod 375 and a manual pull button.

[0035] When the electric trolley enters the up-and-down state, the flexible auxiliary wheel of the wheel's up-and-down function opens, and the electric telescopic rod 371 pulls the lock tongue sleeve 373 backward to allow the locking lock tongue 378 to escape from the button eye 362 on the electric trolley slide rail locking and limit rod plate 360, and the front and rear wheels can enter the front and rear wheel alternating action state with a variable wheelbase.

[0036] When the electric trolley is to return to the flat ground driving state, the flexible auxiliary wheels for the up and down stairs function of the wheels are folded, the electric telescopic rod 371 pushes the lock tongue sleeve 373 forward, allowing the locking lock tongue 378 to extend, the front and rear wheels rotate towards each other or the single wheel group rotates to shorten the front and rear wheel wheelbases, the lock tongue 378 is buckled on the button eye 362 on the electric trolley slide rail locking and limit rod plate 360, and the limit block 364 blocks the limit stop head 363 to complete the locking.

[0037] In order to ensure the smooth going up and down stairs of the electric wheeled trolley, after applying damping grease to the guide rail ball and other places, the power of the front and rear wheel motors needs to take into account the damping force brought by the damping grease during the alternating action of the front and rear wheels when going up and down stairs.

[0038] This embodiment adopts a self-locking worm gear reducer, the wheels cannot reverse drive the motor, and the wheels stop when the motor stops. No additional braking system is required, and the mechanical structure is simple. The disadvantage is that the mechanical transmission efficiency is not high and energy recovery cannot be performed when going downhill or downstairs.

[0039] For the subsequent control of the alternating movements of the front and rear wheels when going up and down stairs, if a fully automatic method is adopted, a vertical rotating scanning laser radar 420 can be set on the front wheel frame 310 and the rear wheel frame 314 of the electric wheeled vehicle to identify the steps under the front and rear wheels, a distance sensor can be set between the front and rear wheels to determine the sliding length of the slide rail, and a spatial angle posture sensor can be set on the body to determine the inclination angle of the body, etc. The controller completes the control of the alternating movements of the front and rear wheels according to the path setting or control intention.

[0040] In order to enable the controller to automatically assist in controlling each wheel when turning at a corner platform, a horizontally rotating scanning laser radar or the like may be provided on the electric wheeled vehicle to detect the distance to surrounding walls.

[0041] Embodiment 2:

[0042] This embodiment is a slide rail type frame chassis and a wheelchair seat part of an electric wheelchair. The slide rail adopts a three-section type, and the drive and braking of the wheel are a motor with a common gear reducer plus an electromagnetic brake.

[0043] The main dimensions of this embodiment are set as follows: the total length of the vehicle body (after the flexible auxiliary wheels are folded) in the flat ground driving state is 1000mm, the total width of the vehicle body is 650mm - the vehicle body can turn around in a space of 1200mmX1200mm, the wheel diameter is 300mm (after the flexible auxiliary wheels are folded), the front and rear wheel wheelbase in the flat ground driving state is 700mm, the closed length of the slide rail is 700mm, the front and rear wheel wheelbase in the uphill and downhill driving state is 900mm (the slide rail slides out 200mm and is locked), the minimum front and rear wheel wheelbase in the upstairs and downstairs driving state is 900mm (the slide rail slides out 200mm and is limited), and the front and rear wheels can slide out more than 600mm when the slide rails go up and down the stairs alternately, see Figure 3 .

[0044] The middle rail 305 is between the outer rail 300 and the inner rail 303 of the three-section slide rail. The outer rail 300 of the slide rail is fixedly mounted on the electric wheelchair slide rail support frame 321. The rear wheel wheel frame 335 is fixed on the inner rail 303 of the slide rail. The rear wheel electrical slip ring and other structures are the same as the corresponding parts of the first embodiment.

[0045] The front wheel support frame adopts a support frame 340 that does not occupy leg space and is fixed on the outer rail 300 of the slide rail and the support frame 321; in order to make the space in front of the wheelchair seat 350 fully open to provide the wheelchair occupant with the greatest convenience, ordinary gear reducers 331 and 332 of the electric wheelchair front wheels are installed on the support support plate 341 and the support frame 342 under the seat 350 connected to the support frame 331; the gear reducers 331 and 322 complete the drive of the front wheel 200 through the driving gear 344, the intermediate gear 346 and the gear ring 347 on the front wheel 200.

[0046] In this embodiment, the front wheel motor reducer and seat telescopic rod support bracket 341 are connected to the upper opening part of the front part of the electric wheelchair slide support frame 321 as a separate structural component by screws; the height of the support frame 321 is greater than the height of the slide outer rail 300, and the upper and lower empty parts are used to leave space for the screw connection between the support frame 321 and other components; the intermediate gear shaft 345 is fixedly installed on the front wheel support frame 340.

[0047] The wheelchair seat 350 is connected to the seat support plate 34a installed on the support frame 321 through the frame connecting plate 353 thereon, and an electric telescopic rod 351 is provided under the front of the seat 350; the electric telescopic rod 351 enables the seat 350 to be adjusted to a horizontal position when the person is facing downstairs or with his / her back facing upstairs; when the person is facing upstairs or with his / her back facing downstairs, the angle of the seat 350 is not adjusted, and the wheelchair occupant is in a semi-reclining position.

[0048] When the electric wheelchair is traveling on flat ground or uphill or downhill, the slide rail is locked in a closed or slightly half-open state, that is, the electric wheelchair slide rail locking and limiting rod plate 361 fixed on the rear wheel support frame 335 cooperates with the locking tongue mechanism and limiting mechanism fixed on the electric wheelchair slide rail support frame 321 to complete the locking of the slide rail in a closed or slightly half-open state.

[0049] The locking tongue mechanism is composed of a slide rail locking locking tongue sleeve sliding seat 370 fixed on the slide rail support frame 321, a locking tongue sleeve 373 that can slide on the locking tongue sleeve sliding seat 370, and a locking locking tongue 378 that slides in the locking tongue sleeve 373.

[0050] The limiting mechanism is composed of a slide rail limiting lock tongue sleeve sliding seat 380 fixed on the slide rail support frame 321, a lock tongue sleeve 382 that can slide on the lock tongue sleeve sliding seat 380, and a limiting lock tongue 383 that slides in the lock tongue sleeve 382.

[0051] When the electric wheelchair changes from a flat ground or uphill or downhill driving state to a stair climbing state, the flexible auxiliary wheel of the wheel's up and down stairs function opens, and the locking tongue 378 disengages from the locking button eye 367 or 365 on the electric wheelchair slide rail locking and limiting rod plate 361; when the locking tongue 378 disengages from the locking button eye 367, the wheel is allowed to rotate to widen the front and rear wheel wheelbases until the slide rail limiting stop 366 at the front of the slide rail locking and limiting rod plate 361 presses over the limiting tongue 383 and is restricted by the limiting tongue 383.

[0052] When the electric wheelchair changes from the state of going up and down stairs to the state of traveling on flat ground or up and down slopes, the flexible auxiliary wheels of the wheel's up and down stairs function are folded, and the locking tongue 378 returns to the position where it can buckle the locking button eye 367 or 365; when the locking button eye 367 is to be buckled, the limit locking tongue 383 is also retracted from the blocking position and pushed back to its blocking position to block the limit stop head 368 after the limit stop head 366 passes its position.

[0053] The locking tongue mechanism and the limiting mechanism cooperate with each other when the electric wheelchair switches between the flat ground state and the uphill and downhill states, and will not be described in detail.

[0054] The conversion process of electric wheelchair on flat ground and going up and down stairs Figure 4 In the figure a, b, c, d, the electric wheelchair is moving upstairs. Figure 4 h, i, j, k in the figure show the process of the electric wheelchair going downstairs Figure 4 In Chinese, u, v, w, x.

[0055] The smoothness of the process of electric wheelchairs going up and down stairs is an important performance requirement after safety. When applying damping grease on the slide rails and ball bearings, a higher damping coefficient needs to be considered. The power of the front and rear wheel motors also needs to be increased accordingly to offset the damping force of the damping grease when the slide rails open and close during the process of going up and down stairs.

[0056] This embodiment uses a motor with an ordinary gear reducer and an electromagnetic brake to drive and brake the wheels; the electromagnetic brake not only brakes the wheels when the battery is low or the power is off, but is mainly used to brake the non-rotating front wheel or rear wheel when the front and rear wheels alternately go up and down the stairs; in the subsequent controller, the function of electronic brake speed control and energy recovery can be added to each wheel to control the rotation speed of the front and rear wheels after crossing the stair step 102 when going down the stairs alternately and the vehicle speed when going downhill; using an ordinary gear reducer, the mechanical transmission efficiency is high and energy recovery can be achieved, but the mechanical structure and electronic control of its braking part are relatively complex.

[0057] In this embodiment, a clutch handle 337 is provided on the electromagnetic brake 336 to cooperate with the hand-pushing function when the front wheel or the rear wheel of the electric wheelchair is an omnidirectional wheel.

[0058] The subsequent control of the alternating movements of the front and rear wheels when going up and down stairs, if a semi-automatic method is adopted, based on the setting of the slide rail slide length sensor and the body angle posture sensor, the control panel can be designed as follows: Figure 5 As shown; after the conversion switch 413 is turned to the stair mode, the flexible auxiliary wheel on the wheel is unfolded, the locking tongue 378 exits the locking button eye 367 or 365 backwards, and the controller enters a mode in which the front and rear wheels can only rotate alternately, and the selection button 41k is activated. When the selection button 41k is pressed, the joystick 411 controls the front wheel (or the rear wheel), and when the selection button 41k is released, the longitudinal rod 411 controls the rear wheel (or the front wheel); when the body angle posture sensor detects that the body angle is a front downward depression angle, the controller continuously adjusts the seat 350 to a horizontal position through the electric telescopic rod 351 automatically; in the flat mode, after the rear wheel position switching button 41a is pressed, the indicator light of the position to be switched to (the rear wheel backward pull-away position indicator light 41b or the rear wheel front position indicator light 41c) flashes, and when the wheelchair is stationary, the joystick 411 can only control the front wheel or the rear wheel, and the corresponding position indicator light lights up after the switching is completed.

[0059] For the subsequent control of the alternating movements of the front and rear wheels when going up and down stairs, if a fully automatic method is adopted, a vertical rotating scanning laser radar 420 can be set at the bottom box 348 of the front wheel transmission gear group protection box of the electric wheelchair and at the rear wheel frame 335 to identify the steps under the front and rear wheels, a distance sensor can be set between the front and rear wheels to determine the sliding length of the slide rail, and a spatial angle posture sensor can be set on the body to determine the tilt angle of the wheelchair, etc. The controller completes the control of the alternating movements of the front and rear wheels according to the control intention of the joystick.

[0060] In order to enable the controller to automatically assist in controlling each wheel when turning at a corner platform, a horizontally rotating scanning laser radar 421 may be provided on the side of the electric wheelchair body to detect the distance to the surrounding walls.

[0061] The above two embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Technicians in these fields may modify the technical solutions recorded in the above embodiments, or make equivalent substitutions for some of the technical features therein; and these modifications and substitutions are all within the scope of protection of the claims attached to the present invention.

Claims

1. A frame type with wheels that can go up and down stairs, characterized in that: The longitudinal main beam of the frame adopts a slide rail type. The wheel frames of the front and rear wheels that can go up and down stairs are respectively connected to the inner and outer rails or the outer and inner rails of the longitudinal slide rail main beam. The front and rear wheels are driven by a motor with a reducer and can be braked.

2. The frame type with wheels that can go up and down stairs according to claim 1 is characterized in that: The front and rear wheels are driven by an electric motor with a conventional gear transmission, and each wheel has its own electronically controlled braking system.

3. The frame type with wheels capable of climbing up and down stairs according to claim 1 is characterized in that: The front and rear wheels are driven and braked by an electric motor equipped with a worm gear reducer with self-locking function.

4. The stair-climbing method of the frame type equipped with stair-climbing wheels according to any one of claims 1 to 3, characterized in that: The front and rear wheels independently and alternately complete the up and down stairs movements.

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