LU501289B1 - Double-track wheelchair for going up and down stairs - Google Patents

Abstract

The invention discloses a double-track wheelchair for going up and down stairs, which comprises a base frame, on which a seat is installed, and a track device is installed below the base frame, and is characterized in that a pair of flat wheels are installed at the front and rear ends of the track device respectively; in normal driving state, the lower surface of the flat wheels is higher than the lower surface of the track, and a track lifting control mechanism is also installed between the base frame and the track device, which can control the track to rise upwards and make its lower surface higher than the lower surface of the flat wheels.

Description

DESCRIPTION HUS01289 DOUBLE-TRACK WHEELCHAIR FOR GOING UPAND DOWN

STAIRS

TECHNICAL FIELD The invention relates to a mobile wheelchair, in particular to a double-track wheelchair for going up and down stairs.

BACKGROUND Wheelchair or mobile wheelchair refers to a movable chair specially used by the elderly or people with inconvenient legs and feet, and the lower end of which is equipped with wheels instead of walking. Generally speaking, a pair of larger walking wheels are installed at the lower ends of both sides, and then a pair of smaller auxiliary wheels are installed at the front sides. This kind of wheelchair is more convenient to walk on the flat ground, but it is not convenient to climb stairs.

This kind of wheelchair using track as walking mechanism is more convenient to use when going up and down stairs. At the same time, when walking on flat ground, when the road surface is uneven, the stability of wheelchair walking can be greatly improved by track. However, when walking on a very flat ground, continuing to use the track will reduce the walking speed of the wheelchair, accelerate the wear of the track mechanism and shorten the service life of the wheelchair.

SUMMARY In view of the above-mentioned shortcomings of the prior art, the technical problem to be solved by the patent of the present invention is: how to provide a double-track wheelchair which can better control the wheelchair to adapt to different flatness conditions to walk on the ground, conveniently control the wheelchair to go up and down stairs, reduce the track wear and prolong the service life.

In order to solve the above technical problems, the patent of the present invention adopts the following technical scheme.

A double-track wheelchair for going up and down stairs comprises a base frame, on which a seat is installed, and a track device is installed below the base frame. It is characterized in that a pair of flat wheels are installed at the front and rear ends of the track device respectively; in normal driving state (running with track support), the HUS01289 lower surface of the flat wheels is higher than the lower surface of the track, and a track lifting control mechanism is also installed between the base frame and the track device, which can control the track to rise upwards and make its lower surface higher than the lower surface of the flat wheels.

In this way, the wheelchair can control the lifting of the track device, and when the road surface is uneven, the wheelchair can walk under the support of the track, which greatly improves the walking stability of the wheelchair and the comfort of the passengers. When the road surface is flat, the track rises and walks with the flat wheels installed at the front and rear ends of the track, so as to improve the walking portability, better control the wheelchair forward, avoid the track from reducing the walking speed and wear, reduce the track walking noise and prolong the service life of the wheelchair. Whether the road surface is flat or not can be controlled by the passengers after observation and judgment, or can be automatically controlled by the detection feedback of the vibration sensor installed on the wheelchair. It is judged that the road surface is uneven when the wheelchair detects large vibration while driving on the ground, and it is judged that the road surface is flat when the vibration is small. The specific control threshold can be adjusted according to the user's comfort.

Further, when the ground inclination is large, the track device under the wheelchair can also be controlled to descend, so that the track contacts with the ground and supports the wheelchair.

In this way, when the wheelchair walks on the ground, the ground inclination is judged first, and when the inclination is larger, the track is controlled to descend and contact with the ground to support driving, so as to better improve the stability of the wheelchair driving control. When the inclination of the ground is small, the track is controlled according to the flatness of the ground, so that the ground driving control of the wheelchair is more reliable and stable. Among them, the degree of ground inclination can be controlled by the observation and judgment of the passengers, or can be automatically controlled by the detection feedback of the wheelchair inclination detection device installed on the wheelchair.

Further, the base frame includes two front arms and two rear arms which are HUS01269 arranged side by side from left to right, the rear end of the front arm and the front end of the rear arm on the same side are inclined upward and connected to form a triangle, and there are horizontal connecting members (in practice, the connecting members include a rear arm connecting plate and a front arm connecting plate) between the two front arms and/or between the two rear arms and are connected into a whole, the length of the front arms is less than that of the rear arms, and the seat is installed in the front half of the rear arms.

This base frame has the advantages of simple structure, stable center of gravity, and convenient adjustment and control of the seat.

Further, the track device comprises two pairs of track mounting plates which are left and right symmetrical and arranged in front and back, a row of track axles are horizontally installed on the track mounting plates to the outside, track wheels are installed on the track axles, and tracks are wound around the track wheels to form two pairs of tracks which are left and right symmetrical and arranged in front and back, and the rear ends of a pair of track mounting plates in front and the front ends of a pair of track mounting plates in rear are simultaneously hinged on a lifting rotating shaft which is horizontally arranged in left and right directions. The front parts of a pair of front track mounting plates are respectively rotatably connected with the front ends of the corresponding front arms, the rear parts of a pair of rear track mounting plates are respectively rotatably connected with the rear ends of the corresponding rear arms, the front ends of the pair of front track mounting plates are also provided with a pair of flat wheels, and the rear ends of the pair of rear track mounting plates are also provided with a pair of flat wheels.

In this way, the front and the rear of the track device are respectively provided with a pair of tracks which can be rotatably connected, so that the structure is simple, the track installation is stable and reliable, and the lifting control of the track device can be conveniently realized through the lifting rotating shaft at the rotating joint of the front and the rear tracks. During the lifting control process of the track device, the included angle between the front track and the rear track is also formed, which can be further used when going up and down stairs, and it is convenient to improve the stair HUS01289 climbing performance of wheelchair. As a better choice, the length of the front track mounting plates and tracks is less than that of the rear track mounting plates and tracks. In this way, the rear tracks can independently support the center of gravity of the whole wheelchair, and it is convenient to better realize the control of the angle change of the front and rear track when climbing stairs, and better maintain the stability of the center of gravity in the control process.

Further, the track lifting control mechanism includes an obliquely arranged lifting screw, the lower end of which is rotatably connected to the middle of the lifting rotating shaft, the upper end of which extends obliquely backward and upward and passes through the rear arm connecting plate connected between two rear arms, the rear arm connecting plate is provided with a screw yielding hole for the lifting screw to pass through, and nut seat mounting lugs are arranged on both sides of the screw yielding hole. A nut seat is hinged on the nut seat mounting lugs, a lifting nut which is screwed with the lifting screw is mounted on the nut seat, and a lifting motor which is in transmission connection with the lifting nut is also mounted on the nut seat; the rear end of the front arm and the front end of the rear arm are rotatably connected. Further, the lifting motor is a stepper motor, which is more convenient and accurate to control.

In this way, in the process of walking on the ground, two pairs of track mounting plates and two pairs of front and rear tracks are in a horizontal state when the ground flatness is low and the track walking state is needed. When the ground flatness is high, when the track needs to be lifted is changed into walking supported by flat wheels, the lifting nut is controlled to rotate by the lifting motor, and the lifting screw is driven to lift up by the screw nut transmission mechanism formed. With the connecting rod transmission pair formed by the lifting screw, the front and rear track mounting plates and the front and rear arms, when the connecting position of the two pairs of track mounting plates is lifted up, the two pairs of flat wheels at the front and rear ends of the tracks can tilt downward and contact with the ground, so that the wheelchair can be driven by the flat wheels. Therefore, the above-mentioned structure has the advantages of simple structure, convenient control, stable and reliable state transition,

accurate control of lifting height and so on.

HUS01269

At the same time, the above-mentioned structure can also be beneficial to the auxiliary control of the wheelchair going up and down stairs.

Specifically, when the wheelchair needs to climb the stairs (the walking state of track support is described in front of the stairs above), after the front ends of the front tracks touch the lowest step of the stairs, the lifting screw is controlled to extend downward; (Because the seat is installed on the front half of the rear arms), after the lifting screw extends downward (under the joint action of the above-mentioned connecting rod transmission pair), the front end of the track mounting plate in front will be tilted upward (because the rear arms are longer, the center of gravity of the wheelchair can remain stable at this time), and when the front end of the track mounting plate is tilted to match the inclination of the stairs, control the lifting screw to stop moving; drive the seat to continue to move forward, and then control the seat to move forward while controlling the lifting screw to reverse reset after the whole track in front contacts with the stair steps.

After the front tracks and the rear tracks are restored to the same linear direction, they will start climbing the stairs obliquely upward.

After climbing the stairs until the front ends of the front tracks exceed the top step, the lifting screw can be controlled to lift upwards, so that an upward inclination angle is formed between the front tracks and the rear tracks, so that the front ends of the front tracks can contact the ground at the upper end of the stairs in advance to improve the support stability, when the rear tracks exceed the top step of the stairs, the lifting screw can be controlled to reverse reset, and the front tracks and the rear tracks can be restored to a horizontal state and support running.

When going down the stairs, the above control process can be controlled by the same principle when running in reverse.

Therefore, the wheelchair can be very stable and reliable in the process of going up and down the stairs, especially in the transition stage of the connection between the stair steps and up and down the flat ground, which can better increase the support contact points between the wheelchair and the ground and the steps, and greatly improve the stability of the transition position of the wheelchair through the stair ground connection.

Therefore, the ability and stability of the wheelchair to climb stairs can be greatly improved.

Furthermore, the track mounting plate is also provided with a track walking HUS01289 motor which is in transmission connection with the track wheel, and a flat wheel walking motor which is in transmission connection with the flat wheel. In this way, the tracks and the horizontal wheels are controlled by the corresponding motors, which can conveniently improve the flexibility and reliability of control.

Furthermore, the base frame is also equipped with an automatic control system. The automatic control system includes a control center, and the lifting motor, track walking motor and flat wheel motor are respectively connected with the control center. The automatic control system also includes a vibration sensor and wheelchair inclination detection device (not shown in the figure) installed on the base frame, which are respectively connected with the control center. In practice, the wheelchair inclination detection device can be implemented by inclination sensor or gyroscope. When the gyroscope is used, it can also detect the acceleration of wheelchair at the same time, so as to better realize the auxiliary control.

In this way, the control center can set up an automatic control program for ground walking, and realize the detection and control of the wheelchair state by means of the vibration sensor and the wheelchair inclination detection device. When the detection value of the wheelchair inclination detection device is greater than the control threshold, it is judged that the ground inclination is in a steep state. At this time, the tracks are controlled to descend to the front-rear linear state as a whole and contact with the ground, and the wheelchair is supported by the tracks. When the detection value of the wheelchair inclination detection device is less than the control threshold, the ground inclination is judged to be flat, and then the value of the vibration sensor is detected. When the value of the vibration sensor is less than the control threshold, the ground is judged to be flat, and the climbing of the tracks depends on the flat wheels installed at the front and rear ends of the tracks and the ground contact support to walk; when the value of the vibration sensor is greater than the control threshold, the ground is judged to be uneven, and then the tracks are controlled to descend and contact with the ground support to walk. Therefore, the above-mentioned automatic control system can realize the automatic detection of various situations and the automatic switching control to control the driving state of HUS01289 wheelchairs under the conditions of inclined ground (uphill and downhill) and horizontal ground, as well as the conditions of flat ground and uneven ground during horizontal ground, which greatly improves the stability of wheelchair driving. When implemented, the main control chip of the control center can adopt STM32 series 32-bit Flash microcontroller based on ARM Cortex™-M processor, which can provide new development freedom for MCU users. It includes a series of 32-bit products, which integrates the characteristics of high performance, real-time function, digital signal processing, low power consumption and low voltage operation, while maintaining the characteristics of high integration and easy development. In addition, during implementation, the control center can communicate with the mobile phone, and some control programs and operation interfaces can be installed on the mobile phone, which is more convenient for users to control and operate.

Further, the rear ends of the rear arms have extension arms extending horizontally backward, and the control center is installed on the connecting plate between the extension arms. Therefore, it is convenient to install and set the control part, and it is beneficial to keep the overall center of gravity of the wheelchair in a relatively backward position, so that the rear track can support the weight of the wheelchair independently, which is convenient for state transition control.

Furthermore, a horizontal docking mechanism of the track mounting plate is also arranged between the front track mounting plate and the rear track mounting plate, wherein the horizontal docking mechanism of the track mounting plate comprises a docking telescopic rod device which is horizontally and fixedly installed at the rear end of the front track mounting plate or the front end of the rear track mounting plate, and also comprises a plug sleeve which is arranged on the track mounting plate at the other end for facing the docking telescopic rod device.

In this way, when the track mounting plate is used for walking in contact with the ground, the telescopic rod of the docking telescopic rod device can be controlled to extend and be inserted into the plug sleeve of the track mounting plate at the other end, so that the front and rear track mounting plates are fixedly connected into a whole along a straight line. In this way, a stable triangular support is formed between the HUS01289 front and rear track mounting plates and the front and rear arms, thus avoiding the influence of the instability of the four-bar linkage on the driving stability of the wheelchair, and also liberating the support pressure of the lifting screw, and avoiding the thread damage or seizure between the lifting screw and the lifting nut due to excessive axial pressure; the stable and normal operation of the lifting control mechanism is ensured, and the service life of the device is prolonged. Among them, the docking telescopic rod device is preferably realized by electric cylinder, which is more convenient to control.

Furthermore, the front and rear two pairs of track mounting plates have short-circuiting fixed arms (short-circuiting means relatively short length) extending obliquely inward and upward (the rear upper part of the front track mounting plate and the front upper part of the rear track mounting plate) at positions close to the outer ends (referring to the positions where the front track mounting plate is close to the front end and the rear track mounting plate is close to the rear end), and the track mounting plates are rotatably connected with the front end of the front arm and the rear end of the rear arm respectively by means of the short-circuiting fixed arms; the outer ends of the two pairs of track mounting plates in the front and back directions are respectively connected with a flat wheel mounting arm outwards, one end of the flat wheel mounting arm is vertically rotatably connected to the end of the track mounting plate, and the other end is provided with a flat wheel, and the flat wheel motor is mounted on the flat wheel mounting arm, and the track mounting plate is also provided with a flat wheel mounting arm rotation control motor which is in transmission connection with the flat wheel mounting arm.

After this optimization, it is convenient to enlarge the adjustable range of the rotatable angle between the track mounting plates and the front and rear arms, and it is also convenient to flexibly adjust the vertical height of the flat wheel as required. More importantly, by setting the length and inclination angle of the short-circuiting fixed arm, the front and rear short-circuiting fixed arms can just rotate to the vertical state when the lifting screw is lifted upwards and changed into the walking state supported by flat wheels; at this time, it is only necessary to control the rotation of the 17501289 flat wheel mounting arm to be vertical by the flat wheel mounting arm rotation control motor, so that the flat wheel can directly transmit the supporting force upward to the rotating shaft at the end of the base frame through the vertical flat wheel mounting arm and the short-circuiting fixed arm. Therefore, when the wheelchair is supported by the flat wheels, the vertical pressure on the flat wheels can be offset by the rotating shaft directly opposite in the vertical direction, so as to avoid excessive support pressure acting on the lifting screw, resulting in excessive axial pressure between the lifting screw and the lifting nut, resulting in thread damage or seizure; the stable and normal operation of the lifting control mechanism is ensured, and the service life of the device is prolonged.

Further, the automatic control system also includes a flat wheel pressure detection sensor installed between the mounting shaft of the flat wheel and the mounting arm of the flat wheel, and a track wheel pressure detection sensor installed between the mounting shaft of each track wheel and the track mounting plate, wherein the flat wheel pressure detection sensor and the track wheel pressure detection sensor are respectively connected with the control center.

In this way, in the process of controlling the wheelchair to go up and down stairs, the automatic control can also be realized by the automatic control program for going up and down stairs set in the control center. Specifically, when the wheelchair is walking on flat ground, when the flat wheels at the front end touch the stairs, the flat wheel pressure detection sensor detects the touched pressure signal, and can start to control the lifting screw to extend downward, so that the front ends of the front tracks are gradually tilted up and ready to climb the stairs; in the process of climbing stairs, the pressure change can be detected by each track wheel pressure detection sensor to judge and control and adjust the driving condition of wheelchair. Specifically, when climbing the stairs, the wheelchair controls the front ends of the front tracks to tilt upward and gradually contact with the stairs. At this time, the pressure change of each track wheel on the front tracks gradually increases from front to back. When each track wheel pressure detection sensor on the front tracks detects that the pressure is balanced, it is judged that the front tracks have completely entered the stairs at this HUS01289 time, and the included angle between the front tracks and the rear tracks is consistent with the included angle of the stair inclination. At this time, continue to control the wheelchair to move forward and control the lifting screw to gradually reset upwards and reversely until the pressure of each track wheel on the rear track is restored and the pressure of each track wheel on the front tracks is consistent; at this time, it is judged that the front and rear tracks have entered the stairs; then control the lifting screw to stop moving and keep the front and rear tracks in a straight state to climb the stairs; when climbing stairs, when it is detected that the pressure of the track wheels on the front tracks suddenly empties from front to back, it is judged that the wheelchair has reached the upper position of the stairs at this time, and after it is detected that the pressure of the track wheel on the front track is completely emptied, the wheelchair is controlled to stop; then, the lifting screw is controlled to lift upwards, so that the front ends of the front tracks gradually rotate downwards. When the track wheels on the front tracks re-detect the pressure, it is judged that the front tracks has landed. At this time, the wheelchair is controlled to move forward while the lifting screw 1s controlled to reset gradually downwards and reversely. After the pressure of each track wheel on the front tracks and the rear tracks is consistent, it is judged that the wheelchair enters the horizontal ground above the stair steps to complete the stair step climbing control process.

Then, the automatic control process of down stairs steps is as follows: when the pressure of each track wheel on the front tracks suddenly empties from front to back, it is judged that the wheelchair has entered the upper edge of down stairs steps; when the pressure of each track wheel on the front track is all emptied, the wheelchair is first controlled to stop, and then the lifting screw is controlled to lift upwards, so that the front ends of the front tracks rotate downwards; when the pressure of each track wheel on the front track recovers, it is judged that the front tracks have contacted the down stairs steps; at this time, the wheelchair is controlled to continue to move forward and then the lifting screw is controlled to reverse reset; until the pressure of each track wheel on the rear tracks recovers and the pressure of each track wheel on the front tracks keeps the same; at this time, it is judged that both the front and rear HUS01289 tracks have entered the down stairs; then control the lifting screw to stop moving and keep the front and rear tracks straight down the stairs; when the flat wheels at the front end suddenly detect the touched pressure signal when going down the stairs, it is judged that the front tracks have reached the ground below the stairs, at this time, the lifting screw is gradually controlled to extend downwards, so that the front tracks are tilted upwards, the front resistance is reduced, and the pressure of all track wheels on the rear tracks keeps moving forward consistently; when the pressure of the front track wheels on the rear tracks suddenly increases, it is judged that the rear tracks begin to enter the ground below the stairs, and at this time, the lifting screw is controlled to reset upwards; until the rear tracks completely enter the ground below the stairs, the pressure of the track wheels on the front and rear tracks always stops the movement of the lifting screw, and the front and rear tracks keep running in a straight line to complete the automatic control of the stairs. Therefore, the wheelchair can be operated and controlled up and down stairs very stably and reliably. In the above-mentioned automatic control process, the wheelchair inclination detection device in the automatic control system can also be used to control the wheelchair inclination state, so as to improve the reliability of judging the wheelchair inclination state and the stability of control.

Further, the front end of the seat is bent and extended forward and downward and provided with pedals. This is more convenient for people to ride.

Furthermore, a seat adjusting device is also arranged between the seat and the base frame, and the seat adjusting device comprises a seat rotation adjusting mechanism and a seat fore-and-aft adjusting mechanism which are arranged between the seat and the base frame.

In this way, it is convenient to adjust the front and back movement and rotation of the seat, and it is convenient for passengers to get on and off the wheelchair.

Further, the seat rotation adjusting mechanism comprises a pair of seat supporting lug plates which are oppositely arranged left and right and installed on the left and right sides of the base frame, and a pair of seat mounting plates which are positioned inside the seat supporting lug plates; the seat is installed between the seat HUS01289 mounting plates; the upper end positions between the seat mounting plates and the seat supporting lug plates on the two sides are respectively rotatably connected by the seat rotating shafts in the left and right directions; and an arc-shaped groove is arranged below the outer side of the seat mounting plates; the lower surface of the groove is a section of internal gear with the seat rotating shaft as the center, the seat supporting lug plate is provided with an external gear meshed with the internal gear, and the seat supporting lug plate is also provided with a seat rotation control motor which is in transmission connection with the external gear.

In this way, the seat rotation adjusting mechanism can control the rotation of the external gear by the seat rotation control motor, and drive the seat mounting plate to rotate along the seat rotation axis through the engagement of the external gear and the internal gear, thus realizing the rotation adjustment control of the seat, and having the advantages of simple structure and convenient and reliable control.

Furthermore, the seat fore-and-aft adjusting mechanism comprises the seat mounting plates, wherein the lower ends of the two seat mounting plates are horizontally and fixedly connected to form a U-shaped member as a whole; the bottom of the U-shaped member is provided with front and rear slide rails along the front and rear directions; the lower end of the seat is slidably fitted on the front and rear slide rails; the U-shaped member is also provided with a telescopic device for seat fore-and-aft adjustment arranged along the front and rear directions; and the executive end of the telescopic device for seat fore-and-aft adjustment is connected with the seat.

In this way, it is possible to control the seat to slide back and forth on the front and rear slide rails that drive the U-shaped member by controlling the extension or retraction of the executive end of the telescopic device for seat fore-and-aft adjustment of the seat, thus realizing the adjustment of the position of the seat in the front and rear direction. Therefore, the seat fore-and-aft adjusting mechanism has the advantages of simple structure and convenient and reliable control. At the same time, the seat fore-and-aft adjusting mechanism is integrated on the basis of the seat rotation adjusting mechanism, so that the seat can realize the front and rear movement 17501289 adjustment while rotating adjustment control, which is very convenient for passengers to adjust the seat position when getting on and off the seat, so that getting on and off the seat is smoother and more stable.

Further, the telescopic device for seat fore-and-aft adjustment includes a stepper motor for seat fore-and-aft adjustment installed on the U-shaped member, which is connected with the seat through a screw nut transmission mechanism for seat fore-and-aft adjustment and can control the seat to move forward and backward.

In this way, the stepper motor is used to adjust and control the front and back movement of the seat through the screw nut mechanism, which has the advantages of accurate and controllable control and good stability. In addition, all the motors and electrical equipment involved in the patent scheme of the invention can be connected with the control center and can be conveniently controlled.

Therefore, through the control process of the seat adjusting device, when the passenger needs to use the wheelchair, the seat is first controlled to move to the front end in the front-back direction, and then the seat is controlled to rotate forward, so that the front end of the seat is tilted downward (especially the foot position of the front end of the seat is in contact with the ground downward), which is convenient for the user to climb the seat; after the user climbs up the seat, the seat is controlled to rotate and reset backward, and then moved to reset backward, so that the user is in the normal sitting position, and the whole center of gravity of the wheelchair is adjusted to be backward, so that it is more stable and reliable in the driving process.

Further, the seat adjusting device also includes a seat up-down adjusting mechanism, which includes up-down slide rails installed on the upper surfaces of the rear arms at both sides of the base frame along the length direction, the lower ends of the seat supporting lug plates are slidably installed on the up-down slide rails, and a telescopic device for seat up-down adjustment is fixedly installed between the rear arms at both sides along the length direction of the rear arms, and the executive end of the telescopic device for seat up-down adjustment is connected with the seat supporting lug plates.

In this way, by further controlling the extension or retraction of the executive end HUS01289 of the telescopic device for seat up-down adjustment, the seat can be controlled to slide up and down obliquely on the upper surface of the rear arm along with the whole seat supporting lug plate, so as to realize the adjustment of the center of gravity in the up and down direction of the seat, so as to facilitate the adjustment of the center of gravity position in the process of passengers getting on and off the seat and controlling the seat to go up and down stairs to better maintain balance and stability. And the seat up-down adjusting mechanism has the characteristics of simple structure and reliable control. In addition, in this structure, the upper and lower slide rails are obliquely arranged, so that they can better cooperate with the base frame structure and improve the stability of sliding control; at the same time, although the upper and lower slide rails are obliquely arranged, the seat up-down adjusting mechanism only needs to be used together with the seat rotation adjusting mechanism and the seat fore-and-aft adjusting mechanism, which can also realize the adjustment of the height of the center of gravity of the wheelchair without changing the front and rear center of gravity positions.

Specifically, when the passenger needs to use the wheelchair, the seat can be controlled to move forward and upward along the upper surface of the rear arm to the topmost by the seat up-down adjusting mechanism, and then the seat can be controlled to move forward in the horizontal direction and rotate forward, so that the front end of the seat tilts downward (especially the stepping position of the front end of the seat touches the ground downward), which is convenient for the user to climb the seat; after the user climbs up the seat, first control the seat to rotate and reset backward, then move and reset backward, and then further control the seat to move and reset backward and downward along the upper surface of the rear arm through the seat up-down adjusting mechanism, so that the center of gravity of the wheelchair is more backward and lower, and the wheelchair is more stable and reliable during driving.

In the process of going up and down stairs by wheelchair, before the front tracks are lifted or suspended, the seat can be controlled to move backward and downward, so that the overall center of gravity of the wheelchair is backward. When the wheelchair runs on the stair steps, the seat can be controlled to move to the lower HUS01289 position through the seat up-down adjusting mechanism, and then to the front position through the seat fore-and-aft adjusting mechanism, so that the seat is in a lower position and the center of gravity is close to the middle of the wheelchair, which is convenient to improve the stability of moving on the stair adjustment.

Furthermore, a seat inclination detection device is installed on the seat, and the seat inclination detection device is connected with the control center.

In this way, the control center can realize the following automatic detection control when the wheelchair goes up and down the stairs or up and down the slope. The inclination angle of the wheelchair base frame is detected by the wheelchair inclination detection device, and the inclination angle of the seat is detected by the seat inclination detection device. When the angle changes are detected (at this time, it is judged that the wheelchair is in the inclined state of going up and down stairs or up and down slopes), the seat rotation is controlled by the seat rotation adjusting mechanism, so that the detection value of the seat inclination detecting device is restored to the value of the horizontal ground walking state, and the comfort of the passengers is ensured; at the same time, the inclination angle of the wheelchair base frame is continuously monitored by the wheelchair inclination detection device, so as to facilitate the conversion and control of the track lifting in the process of the wheelchair going up and down stairs, and better improve the riding comfort of the passengers and the stability of the seat when passing through stairs or slopes.

Further, the telescopic device for seat up-down adjustment includes a stepper motor for seat up-down adjustment installed between rear arms at both sides, which is connected with the seat supporting lug plate through a screw nut transmission mechanism for seat up-down adjustment and can control the seat supporting lug plate to move up and down.

In this way, the stepper motor is used to adjust and control the up and down movement of the seat through the screw nut mechanism, which has the advantages of accurate and controllable control and good stability.

To sum up, the invention patent has the advantages of being able to better control HUS01289 the wheelchair to adapt to different flatness conditions to walk on the ground, reducing the wear of the track and prolonging the service life.

BRIEF DESCRIPTION OF THE FIGURES FIG. 1 is a schematic diagram of the three-dimensional structure of the wheelchair of the present invention.

FIG. 2 is a schematic view of the structure of FIG. 1 from below.

FIG. 3 is a schematic view of the structure of FIG. 1 from another angle.

FIG. 4 is a schematic structural view of the separate track device in FIG. 1.

FIG. 5 is a structural schematic diagram of the single base frame, the seat supporting lug plate and the seat mounting plate on it in FIG. 1.

FIG. 6 is a schematic structural diagram of the horizontal docking mechanism of the single track mounting plate of the wheelchair of the present invention.

DESCRIPTION OF THE INVENTION Next, the patent of the present invention will be further described in detail with reference to the attached drawings.

Specifically, as shown in FIG. 1 to FIG. 4, a double-track wheelchair for going up and down stairs includes a base frame, on which a seat 1 is installed, a track device is installed below the base frame, and a pair of flat wheels 2 are installed at the front and rear ends of the track device respectively. In normal driving state (running with track support), the lower surface of the flat wheels 2 is higher than the lower surface of the track, and a track lifting control mechanism is also installed between the base frame and the track device, which can control the track to rise upwards and make its lower surface higher than the lower surface of the flat wheels.

In this way, the wheelchair can control the lifting of the track device, and when the road surface is uneven, the wheelchair can walk under the support of the track, which greatly improves the walking stability of the wheelchair and the comfort of the passengers. When the road surface is flat, the track rises and walks with the flat wheels installed at the front and rear ends of the track, so as to improve the walking portability, better control the wheelchair forward, avoid the track from reducing the walking speed and wear, reduce the track walking noise and prolong the service life of HUS01289 the wheelchair. Whether the road surface is flat or not can be controlled by the passengers after observation and judgment, or can be automatically controlled by the detection feedback of the vibration sensor installed on the wheelchair. It is judged that the road surface is uneven when the wheelchair detects large vibration while driving on the ground, and it is judged that the road surface is flat when the vibration is small.

The specific control threshold can be adjusted according to the user's comfort.

When the ground inclination is large, the track device under the wheelchair can also be controlled to descend, so that the track contacts with the ground and supports the wheelchair. In this way, when the wheelchair walks on the ground, the ground inclination is judged first, and when the inclination is larger, the track is controlled to descend and contact with the ground to support driving, so as to better improve the stability of the wheelchair driving control. When the inclination of the ground is small, the track is controlled according to the flatness of the ground, so that the ground driving control of the wheelchair is more reliable and stable. Among them, the degree of ground inclination can be controlled by the observation and judgment of the passengers, or can be automatically controlled by the detection feedback of the wheelchair inclination detection device installed on the wheelchair.

Among them, the base frame includes two front arms 3 and two rear arms 4 which are arranged side by side from left to right, the rear end of the front arm and the front end of the rear arm on the same side are inclined upward and connected to form a triangle, and there are horizontal connecting members (in practice, the connecting members include a front arm connecting plate 5 and a rear arm connecting plate 6) between the two front arms 3 and/or between the two rear arms 4 and are connected into a whole, the length of the front arms 3 is less than that of the rear arms 4, and the seat 1 is installed in the front half of the rear arms.

This base frame has the advantages of simple structure, stable center of gravity, and convenient adjustment and control of the seat.

Wherein, the track device comprises two pairs of track mounting plates 7 which are left and right symmetrical and arranged in front and back, a row of track axles are horizontally installed on the track mounting plates 7 to the outside, track wheels 8 are HUS01289 installed on the track axles, and tracks 9 are wound around the track wheels to form two pairs of tracks 9 which are left and right symmetrical and arranged in front and back, and the rear ends of a pair of track mounting plates in front and the front ends of a pair of track mounting plates in rear are simultaneously hinged on a lifting rotating shaft 10 which is horizontally arranged in left and right directions. The front parts of a pair of front track mounting plates are respectively rotatably connected with the front ends of the corresponding front arms 3, the rear parts of a pair of rear track mounting plates are respectively rotatably connected with the rear ends of the corresponding rear arms 4, the front ends of the pair of front track mounting plates are also provided with a pair of flat wheels 2, and the rear ends of the pair of rear track mounting plates are also provided with a pair of flat wheels 2.

In this way, the front and the rear of the track device are respectively provided with a pair of tracks which can be rotatably connected, so that the structure is simple, the track installation is stable and reliable, and the lifting control of the track device can be conveniently realized through the lifting rotating shaft at the rotating joint of the front and the rear tracks. During the lifting control process of the track device, the included angle between the front track and the rear track is also formed, which can be further used when going up and down stairs, and it is convenient to improve the stair climbing performance of wheelchair. As a better choice, the length of the front track mounting plates and tracks is less than that of the rear track mounting plates and tracks. In this way, the rear tracks can independently support the center of gravity of the whole wheelchair, and it is convenient to better realize the control of the angle change of the front and rear track when climbing stairs, and better maintain the stability of the center of gravity in the control process.

Among them, the track lifting control mechanism includes an obliquely arranged lifting screw 11, the lower end of which is rotatably connected to the middle of the lifting rotating shaft 10, the upper end of which extends obliquely backward and upward and passes through the rear arm connecting plate 6 connected between two rear arms, the rear arm connecting plate is provided with a screw yielding hole 12 for the lifting screw to pass through, and nut seat mounting lugs are arranged on both HUS01289 sides of the screw yielding hole. A nut seat 13 is hinged on the nut seat mounting lugs, a lifting nut which is screwed with the lifting screw is mounted on the nut seat 13, and a lifting motor which is in transmission connection with the lifting nut is also mounted on the nut seat; the rear end of the front arm and the front end of the rear arm are rotatably connected. Further, the lifting motor is a stepper motor, which is more convenient and accurate to control.

In this way, in the process of walking on the ground, two pairs of track mounting plates and two pairs of front and rear tracks are in a horizontal state when the ground flatness is low and the track walking state is needed. When the ground flatness is high, when the track needs to be lifted is changed into walking supported by flat wheels, the lifting nut is controlled to rotate by the lifting motor, and the lifting screw is driven to lift up by the screw nut transmission mechanism formed. With the connecting rod transmission pair formed by the lifting screw, the front and rear track mounting plates and the front and rear arms, when the connecting position of the two pairs of track mounting plates is lifted up, the two pairs of flat wheels at the front and rear ends of the tracks can tilt downward and contact with the ground, so that the wheelchair can be driven by the flat wheels. Therefore, the above-mentioned structure has the advantages of simple structure, convenient control, stable and reliable state transition, accurate control of lifting height and so on.

At the same time, the above-mentioned structure can also be beneficial to the auxiliary control of the wheelchair going up and down stairs. Specifically, when the wheelchair needs to climb the stairs (the walking state of track support is described in front of the stairs above), after the front ends of the front tracks touch the lowest step of the stairs, the lifting screw is controlled to extend downward; (Because the seat is installed on the front half of the rear arms), after the lifting screw extends downward (under the joint action of the above-mentioned connecting rod transmission pair), the front end of the track mounting plate in front will be tilted upward (because the rear arms are longer, the center of gravity of the wheelchair can remain stable at this time), and when the front end of the track mounting plate is tilted to match the inclination of the stairs, control the lifting screw to stop moving; drive the seat to continue to move HUS01289 forward, and then control the seat to move forward while controlling the lifting screw to reverse reset after the whole track in front contacts with the stair steps. After the front tracks and the rear tracks are restored to the same linear direction, they will start climbing the stairs obliquely upward. After climbing the stairs until the front ends of the front tracks exceed the top step, the lifting screw can be controlled to lift upwards, so that an upward inclination angle is formed between the front tracks and the rear tracks, so that the front ends of the front tracks can contact the ground at the upper end of the stairs in advance to improve the support stability, when the rear tracks exceed the top step of the stairs, the lifting screw can be controlled to reverse reset, and the front tracks and the rear tracks can be restored to a horizontal state and support running. When going down the stairs, the above control process can be controlled by the same principle when running in reverse. Therefore, the wheelchair can be very stable and reliable in the process of going up and down the stairs, especially in the transition stage of the connection between the stair steps and up and down the flat ground, which can better increase the support contact points between the wheelchair and the ground and the steps, and greatly improve the stability of the transition position of the wheelchair through the stair ground connection. Therefore, the ability and stability of the wheelchair to climb stairs can be greatly improved.

Among them, the track mounting plate is also provided with a track walking motor 14 which is in transmission connection with the track wheel 8, and a flat wheel walking motor 15 which is in transmission connection with the flat wheel 2. In this way, the tracks and the horizontal wheels are controlled by the corresponding motors, which can conveniently improve the flexibility and reliability of control.

Among them, the base frame is also equipped with an automatic control system. The automatic control system includes a control center 16, and the lifting motor, track walking motor 14 and flat wheel motor 15 are respectively connected with the control center 16. The automatic control system also includes a vibration sensor and wheelchair inclination detection device (not shown in the figure) installed on the base frame, which are respectively connected with the control center 16. In practice, the wheelchair inclination detection device can be implemented by inclination sensor or 17501289 gyroscope. When the gyroscope is used, it can also detect the acceleration of wheelchair at the same time, so as to better realize the auxiliary control.

In this way, the control center can set up an automatic control program for ground walking, and realize the detection and control of the wheelchair state by means of the vibration sensor and the wheelchair inclination detection device. When the detection value of the wheelchair inclination detection device is greater than the control threshold, it is judged that the ground inclination is in a steep state. At this time, the tracks are controlled to descend to the front-rear linear state as a whole and contact with the ground, and the wheelchair is supported by the tracks. When the detection value of the wheelchair inclination detection device is less than the control threshold, the ground inclination is judged to be flat, and then the value of the vibration sensor is detected. When the value of the vibration sensor is less than the control threshold, the ground is judged to be flat, and the climbing of the tracks depends on the flat wheels installed at the front and rear ends of the tracks and the ground contact support to walk; when the value of the vibration sensor is greater than the control threshold, the ground is judged to be uneven, and then the tracks are controlled to descend and contact with the ground support to walk. Therefore, the above-mentioned automatic control system can realize the automatic detection of various situations and the automatic switching control to control the driving state of wheelchairs under the conditions of inclined ground (uphill and downhill) and horizontal ground, as well as the conditions of flat ground and uneven ground during horizontal ground, which greatly improves the stability of wheelchair driving. When implemented, the main control chip of the control center can adopt STM32 series 32-bit Flash microcontroller based on ARM Cortex™-M processor, which can provide new development freedom for MCU users. It includes a series of 32-bit products, which integrates the characteristics of high performance, real-time function, digital signal processing, low power consumption and low voltage operation, while maintaining the characteristics of high integration and easy development. In addition, during implementation, the control center can communicate with the mobile phone,

and some control programs and operation interfaces can be installed on the mobile HUS01289 phone, which is more convenient for users to control and operate.

The rear ends of the rear arms 4 have extension arms 17 extending horizontally backward, and the control center 16 is installed on the connecting plate between the extension arms 17. Therefore, it is convenient to install and set the control part, and it is beneficial to keep the overall center of gravity of the wheelchair in a relatively backward position, so that the rear track can support the weight of the wheelchair independently, which is convenient for state transition control.

In the process of going up and down stairs by wheelchair, before the front tracks are lifted or suspended, the seat can be controlled to move backward and downward, so that the overall center of gravity of the wheelchair is backward. When the wheelchair runs on the stair steps, the seat can be controlled to move to the lower position through the seat up-down adjusting mechanism, and then to the front position through the seat fore-and-aft adjusting mechanism, so that the seat is in a lower position and the center of gravity is close to the middle of the wheelchair, which is convenient to improve the stability of moving on the stair adjustment.

Among them, a seat inclination detection device (not shown in the figure) is also installed on the seat, and the seat inclination detection device is connected with the control center.

In this way, the control center can realize the following automatic detection control when the wheelchair goes up and down the stairs or up and down the slope. The inclination angle of the wheelchair base frame is detected by the wheelchair inclination detection device, and the inclination angle of the seat is detected by the seat inclination detection device. When the angle changes are detected (at this time, it is judged that the wheelchair is in the inclined state of going up and down stairs or up and down slopes), the seat rotation is controlled by the seat rotation adjusting mechanism, so that the detection value of the seat inclination detecting device is restored to the value of the horizontal ground walking state, and the comfort of the passengers is ensured; at the same time, the inclination angle of the wheelchair base frame is continuously monitored by the wheelchair inclination detection device, so as to facilitate the conversion and control of the track lifting in the process of the HUS01289 wheelchair going up and down stairs, and better improve the riding comfort of the passengers and the stability of the seat when passing through stairs or slopes.

Wherein, the telescopic device for seat up-down adjustment comprises a stepper motor for seat up-down adjustment installed between rear arms at two sides, and the stepper motor for seat up-down adjustment is connected with the seat supporting lug plate through a screw nut transmission mechanism for seat up-down adjustment and can control the seat supporting lug plate to move up and down.

In this way, the stepper motor is used to adjust and control the up and down movement of the seat through the screw nut mechanism, which has the advantages of accurate and controllable control and good stability. The motors used to cooperate with the screw nut mechanism in the above scheme all adopt stepper motors. Stepper motor is used because the rotation angle of stepper motor is proportional to the number of pulses, and the motor has the maximum torque when it stops. The accuracy of stepper motor is 3% to 5%, and the error of one step will not accumulate to the next step, so it has better position accuracy, repeatability of motion, excellent start-stop and reverse response. Because there is no brush, the reliability is high, so the life of the motor only depends on the life of the bearing. The response of stepper motor is only determined by digital input pulse, so open-loop control can be adopted, which makes the structure of the motor simpler and the cost can be controlled. Just connecting the load directly to the rotating shaft of the motor can also rotate synchronously at extremely low speed. Because the speed is proportional to the pulse frequency, it has a wide speed range. The output pulse can control the stepper motor, which makes the rotation angle movement, and the moving distance and moving speed can be controlled by the screw rod.

Claims (10)

CLAIMS LU501289

1. À double-track wheelchair for going up and down stairs, comprising a base frame, on which a seat is installed, and a track device is installed below the base frame, characterized in that a pair of flat wheels are installed at the front and rear ends of the track device respectively; in normal driving state, the lower surface of the flat wheels is higher than the lower surface of the track, and a track lifting control mechanism 1s also installed between the base frame and the track device, which can control the track to rise upwards and make its lower surface higher than the lower surface of the flat wheels.

2. The double-track wheelchair according to claim 1, characterized in that the base frame includes two front arms and two rear arms which are arranged side by side from left to right, the rear end of the front arm and the front end of the rear arm on the same side are inclined upward and connected to form a triangle, and there are horizontal connecting members between the two front arms and/or between the two rear arms and are connected into a whole, the length of the front arms 1s less than that of the rear arms, and the seat is installed in the front half of the rear arms.

3. The double-track wheelchair according to claim 2, characterized in that the track device comprises two pairs of track mounting plates which are left and right symmetrical and arranged in front and back, a row of track axles are horizontally installed on the track mounting plates to the outside, track wheels are installed on the track axles, and tracks are wound around the track wheels to form two pairs of tracks which are left and right symmetrical and arranged in front and back, and the rear ends of a pair of track mounting plates in front and the front ends of a pair of track mounting plates in rear are simultaneously hinged on a lifting rotating shaft which is horizontally arranged in left and right directions; the front parts of a pair of front track mounting plates are respectively rotatably connected with the front ends of the corresponding front arms, the rear parts of a pair of rear track mounting plates are respectively rotatably connected with the rear ends of the corresponding rear arms, the front ends of the pair of front track mounting plates are also provided with a pair of flat wheels, and the rear ends of the pair of rear track mounting plates are also provided with a pair of flat wheels. HUS01289

4. The double-track wheelchair as claimed in claim 3, characterized in that the track lifting control mechanism comprises an obliquely arranged lifting screw, the lower end of which is rotatably connected to the middle of the lifting rotating shaft, the upper end of which extends obliquely backward and upward and passes through the rear arm connecting plate connected between two rear arms, the rear arm connecting plate is provided with a screw yielding hole for the lifting screw to pass through, and nut seat mounting lugs are arranged on both sides of the screw yielding hole; a nut seat is hinged on the nut seat mounting lugs, a lifting nut which is screwed with the lifting screw is mounted on the nut seat, and a lifting motor which is in transmission connection with the lifting nut is also mounted on the nut seat; the rear end of the front arm and the front end of the rear arm are rotatably connected.

5. The double-track wheelchair according to claim 4, wherein the lifting motor is a stepper motor.

6. The double-track wheelchair according to claim 4, characterized in that the track mounting plate is also equipped with a track walking motor which is in transmission connection with the track wheel, and is also provided with a flat wheel walking motor which is in transmission connection with the flat wheel.

7. The double-track wheelchair according to claim 6, characterized in that the base frame is also equipped with an automatic control system; the automatic control system includes a control center, and the lifting motor, track walking motor and flat wheel motor are respectively connected with the control center; the automatic control system also includes a vibration sensor and wheelchair inclination detection device installed on the base frame, which are respectively connected with the control center; the rear ends of the rear arms have extension arms extending horizontally backward, and the control center is installed on the connecting plate between the extension arms.

8. The double-track wheelchair as claimed in claim 7, characterized in that a horizontal docking mechanism of the track mounting plate is also arranged between the front track mounting plate and the rear track mounting plate, wherein the horizontal docking mechanism of the track mounting plate comprises a docking HUS01289 telescopic rod device which is horizontally and fixedly installed at the rear end of the front track mounting plate or the front end of the rear track mounting plate, and also comprises a plug sleeve which is arranged on the track mounting plate at the other end for facing the docking telescopic rod device; the front and rear two pairs of track mounting plates have short-circuiting fixed arms extending obliquely inward and upward at positions close to the outer ends, and the track mounting plates are rotatably connected with the front end of the front arm and the rear end of the rear arm respectively by means of the short-circuiting fixed arms; the outer ends of the two pairs of track mounting plates in the front and back directions are respectively connected with a flat wheel mounting arm outwards, one end of the flat wheel mounting arm is vertically rotatably connected to the end of the track mounting plate, and the other end is provided with a flat wheel, and the flat wheel motor is mounted on the flat wheel mounting arm, and the track mounting plate is also provided with a flat wheel mounting arm rotation control motor which is in transmission connection with the flat wheel mounting arm.

9. The double-track wheelchair according to claim 7 or 8, characterized in that the automatic control system also includes a flat wheel pressure detection sensor installed between the mounting shaft of the flat wheel and the mounting arm of the flat wheel, and a track wheel pressure detection sensor installed between the mounting shaft of each track wheel and the track mounting plate, wherein the flat wheel pressure detection sensor and the track wheel pressure detection sensor are respectively connected with the control center.

10. The double-track wheelchair according to claim 9, characterized in that the front end of the seat is bent and extended forward and downward with pedals; a seat adjusting device is also arranged between the seat and the base frame, and the seat adjusting device comprises a seat rotation adjusting mechanism and a seat fore-and-aft adjusting mechanism which are arranged between the seat and the base frame; the seat rotation adjusting mechanism comprises a pair of seat supporting lug plates which are oppositely arranged left and right and installed on the left and right HUS01289 sides of the base frame, and a pair of seat mounting plates which are positioned inside the seat supporting lug plates; the seat is installed between the seat mounting plates; the upper end positions between the seat mounting plates and the seat supporting lug plates on the two sides are respectively rotatably connected by the seat rotating shafts in the left and right directions; and an arc-shaped groove is arranged below the outer side of the seat mounting plates, the lower surface of the groove is a section of internal gear with the seat rotating shaft as the center, the seat supporting lug plate is provided with an external gear meshed with the internal gear, and the seat supporting lug plate is also provided with a seat rotation control motor which is in transmission connection with the external gear;

the seat fore-and-aft adjusting mechanism comprises the seat mounting plates, wherein the lower ends of the two seat mounting plates are horizontally and fixedly connected to form a U-shaped member as a whole; the bottom of the U-shaped member is provided with front and rear slide rails along the front and rear directions; the lower end of the seat is slidably fitted on the front and rear slide rails; the U-shaped member is also provided with a telescopic device for seat fore-and-aft adjustment arranged along the front and rear directions; and the executive end of the telescopic device for seat fore-and-aft adjustment is connected with the seat; the telescopic device for seat fore-and-aft adjustment includes a stepper motor for seat fore-and-aft adjustment installed on the U-shaped member, which is connected with the seat through a screw nut transmission mechanism for seat fore-and-aft adjustment and can control the seat to move forward and backward;

the seat adjusting device also includes a seat up-down adjusting mechanism, which includes up-down slide rails installed on the upper surfaces of the rear arms at both sides of the base frame along the length direction, the lower ends of the seat supporting lug plates are slidably installed on the up-down slide rails, and a telescopic device for seat up-down adjustment is fixedly installed between the rear arms at both sides along the length direction of the rear arms, and the executive end of the telescopic device for seat up-down adjustment is connected with the seat supporting lug plates; LU501289 the seat is also provided with a seat inclination detection device which is connected with the control center; the telescopic device for seat up-down adjustment includes a stepper motor for seat up-down adjustment installed between rear arms at both sides, which is connected with the seat supporting lug plate through a screw nut transmission mechanism for seat up-down adjustment and can control the seat supporting lug plate to move up and down.