A linkage folding wheelchair

Abstract

This application relates to the field of wheelchair technology, and in particular to a linkage folding wheelchair, including a chassis frame, a seat frame, a backrest frame, and armrests. The armrests are installed on both sides of the backrest frame. The seat frame is mounted to the chassis frame via a hinge bracket. The bottom of the backrest frame is rotatably mounted to the seat frame, and the seat frame and backrest frame are linked by a folding arm. When the wheelchair needs to be folded, the locking switch releases the folding arm, causing it to fold downwards. At this time, driven by the hinge bracket, the seat frame folds downwards; simultaneously, driven by the folding arm, the backrest frame and armrests flip forward and fold, forming a linkage fold. When the wheelchair needs to be used, the folding arm is unfolded. At this time, driven by the hinge bracket, the seat frame rises and unfolds; simultaneously, driven by the folding arm, the backrest frame and armrests flip backward and unfold. After the folding arm is unfolded, the locking switch locks it.

Description

Technical Field

[0001] This application relates to the field of wheelchair technology, and in particular to a linkage folding wheelchair. Background Technology

[0002] Wheelchairs are devices that help people with mobility impairments move and get around. While regular wheelchairs provide convenience for users to travel medium to long distances, folding wheelchairs have been developed to address the issue of large storage space requirements and to make them easier for users or caregivers to carry and move.

[0003] However, most current folding wheelchairs require disassembling many structural connection points during the folding process, and then folding each part individually until all parts are folded. This folding method is relatively complex and cumbersome. Therefore, further improvements are needed. Summary of the Invention

[0004] To facilitate wheelchair folding, this application provides a linkage folding wheelchair.

[0005] The technical solution for a linkage folding wheelchair provided in this application is as follows:

[0006] A linkage folding wheelchair includes a base frame, a seat frame, a backrest frame, and armrests. The seat frame is mounted to the base frame via a hinge bracket for lifting and unfolding or folding down. The bottom of the backrest frame is rotatably mounted to the seat frame, and the armrests are mounted on both sides of the backrest frame. Folding arms are installed between the base frame and the backrest frame, and the seat frame and backrest frame are linked by the folding arms. When the folding arms are unfolded, they cause the backrest frame to flip backward and unfold, while simultaneously causing the seat frame to lift and unfold. When the folding arms are folded, they cause the backrest frame to flip forward and fold down, while simultaneously causing the seat frame to fold down. A switch lock is installed between the two sets of folding arms for locking after the folding arms are unfolded.

[0007] By adopting the above technical solution, when the wheelchair needs to be folded, the lock on the folding arm is released, and the folding arm folds downward. At this time, driven by the hinge bracket, the seat frame folds downward; simultaneously, dragged by the folding arm, the backrest frame along with the armrests flips forward and folds up, forming a linked folding mechanism. When the wheelchair needs to be used, the folding arm is unfolded. At this time, driven by the hinge bracket, the seat frame rises and unfolds; simultaneously, dragged by the folding arm, the backrest frame along with the armrests flips backward and unfolds. After the folding arm is unfolded, the lock locks it.

[0008] Optionally, the hinged fork bracket is arranged on the left and right sides; the hinged fork bracket includes two fork arms that are hinged to each other, and the two ends of the two fork arms on one side are respectively hinged to the vehicle underframe and the seat frame, and the two ends of the two fork arms on the other side are each hinged to a sliding member, and the two sliding members are respectively slidably installed on the vehicle underframe and the seat frame in the horizontal direction.

[0009] By adopting the above technical solution, when the hinge bracket unfolds, it causes the seat frame to gradually rise, thereby lifting and unfolding the seat frame. Similarly, when the hinge bracket folds, it causes the seat frame to gradually lower, thereby folding and retracting the seat frame.

[0010] Optionally, the folding arm includes a first arm and a second arm that are rotatably connected to each other, and the end of the first arm away from the second arm is rotatably connected to the vehicle floor frame, while the end of the second arm away from the first arm is fixedly connected to the backrest frame; and during the folding process, the first arm and the second arm fold backward.

[0011] By adopting the above technical solution, during the folding process, the first arm and the second arm fold backward, causing the first arm to drive the backrest frame to flip forward and fold up.

[0012] Optionally, the folding arm includes at least two sets, and the switch lock is installed between the two sets of folding arms for locking them; the switch lock includes a housing, a latch, a first return spring, and a button; latch channels are formed at both the left and right ends inside the housing, and the latch is slidably installed in the latch channels; the first return spring is installed in the latch channel and pushes outward against the latch; the button is pressable and slidably installed outside the housing, and a second return spring is installed between the button and the housing; the button is provided with two unlocking heads, and the latch has an unlocking hole, the inner side wall of the unlocking hole is an unlocking slope, and the two unlocking heads slide against the unlocking slope in the two latches respectively; the second arm has a locking hole for the latch to pop out and lock when the folding arm is unfolded.

[0013] By adopting the above technical solution, when it is necessary to unlock the folding arm, pressing the button causes the unlocking head in the button to press the latch inward along the unlocking slope, causing the latch to disengage from the lock hole and unlock. Similarly, when the folding arm is unfolded, under the action of the first return spring, the latch pops out and inserts into the lock hole to lock the first arm and the second arm, thereby achieving locking after the folding arm is unfolded.

[0014] Optionally, the bottom of the armrest is connected to the seat frame via a support rod, and both ends of the support rod are rotatably connected to the armrest and the seat frame.

[0015] By adopting the above technical solution, the armrests fold along with the backrest frame during folding. During the unfolding of the backrest frame, the armrests unfold along with the backrest frame, and the support of the support rods further enhances the structural strength of the armrest area.

[0016] Optionally, the two rearward ends of the two forks are sliding member connection ends; the sliding member at the top of the hinge bracket is slidably installed on the seat frame via a slide rail, the slide rail having a groove formed inside, and the sliding member sliding within the groove; a first-level limiting port is provided at the bottom of the slide rail, and the first-level limiting port extends into the groove; first front swing locking arms are installed on both the left and right sides of the bottom front side of the backrest frame, and a first-level safety latch extends upward from the end of the first front swing locking arm away from the backrest frame, and during the unfolding of the backrest frame, the first-level safety latch in the first front swing locking arm is inserted into the groove from the first-level limiting port and backs against the back of the sliding member.

[0017] By adopting the above technical solution, during the unfolding of the backrest frame, the primary safety latch in the first front swing arm inserts into the slide groove from the primary limiting port and supports the back of the sliding member, thereby limiting the backward movement of the sliding member within the slide groove and preventing the hinge bracket from folding downward. Therefore, during normal use of the wheelchair, even if the locking mechanism loses its lock on the folding arm due to an accident, the primary safety latch in the first front swing arm can still be used to prevent the hinge bracket from folding downward, further preventing accidental folding of the seat frame and potential injury to the user.

[0018] Optionally, a secondary limiting port is provided on the side of the primary safety latch; secondary safety latches are installed on both the left and right sides of the seat frame, and after the backrest frame is unfolded, the secondary safety latches pass through the seat frame and are inserted into the secondary limiting port in the primary safety latch.

[0019] By adopting the above technical solution, a secondary safety latch is used to connect the primary safety latch to the seat frame during normal use of the wheelchair, thereby further improving the stability of the limiting component.

[0020] Optionally, the secondary safety latch includes a rod head and a rod body, with a gradually narrowing transition portion formed between the rod head and the rod body; a rod sleeve is fixedly installed on the side of the chair frame at the slide rail position, the rod body of the secondary safety latch is inserted into the rod sleeve, and the rod body extends through the chair frame and the slide rail into the slide groove; a retraction spring is installed in the rod sleeve, and the retraction spring is sleeved on the rod body; a first limiting member and a second limiting member are respectively installed at both ends of the retraction spring, the first limiting member is arranged on the outer side and fixedly connected to the rod sleeve; the second limiting member is arranged on the inner side and installed on the rod body; a second front swing locking arm is also installed on the first front swing locking arm, the top of the front end of the second front swing locking arm has an arc-shaped retraction opening, and retraction blocks are formed on both the front and rear sides of the arc-shaped retraction opening, and the retraction blocks gradually increase in size from top to bottom on the outer side, and then gradually decrease in size to transition to the side of the second front swing locking arm.

[0021] By adopting the above technical solution, during the unfolding of the backrest frame, the first and second front swing locking arms swing upward synchronously with the backrest frame. During this process, the transition portion of the secondary safety latch first enters the arc-shaped retraction port of the second front swing locking arm, and under the action of the retraction block, pushes the secondary safety latch outward, causing the rod head of the secondary safety latch to disengage from the slide groove in the slide rail, allowing the primary safety latch of the first front swing locking arm to smoothly insert into the primary limiting port in the slide rail. Then, under the action of the retraction return spring, the rod head of the secondary safety latch inserts into the secondary limiting port of the primary safety latch, achieving linkage limiting.

[0022] Optionally, it also includes a foot pedal, which is mounted on the underbody frame and can be flipped up and folded.

[0023] By adopting the above technical solution, a footrest is provided for users to place their feet; at the same time, the footrest is designed to be able to flip up and fold, so as to further improve the overall folding performance of the wheelchair.

[0024] Optionally, it also includes a seat cushion installed in the seat frame and a backrest cushion installed in the backrest frame.

[0025] In summary, this application includes at least one of the following beneficial technical effects:

[0026] 1. When the wheelchair needs to be folded, release the lock on the folding arm, and the arm folds downwards. At this time, driven by the hinge bracket, the seat frame folds downwards; simultaneously, driven by the folding arm, the backrest frame and armrests flip forward and fold, forming a linked fold. When the wheelchair needs to be used, unfold the folding arm. At this time, driven by the hinge bracket, the seat frame rises and unfolds; simultaneously, driven by the folding arm, the backrest frame and armrests flip backward and unfold. After the folding arm is unfolded, the lock locks it. The folding operation is relatively simple.

[0027] 2. When it is necessary to unlock the folding arm, press the button. The unlocking head in the button will press the latch inward along the unlocking ramp, causing the latch to disengage from the lock hole and unlock. Similarly, when the folding arm is unfolded, under the action of the first return spring, the latch will pop out and insert into the lock hole to lock the first arm and the second arm, thereby achieving locking after the folding arm is unfolded.

[0028] 3. During the unfolding of the backrest frame, the primary safety latch in the first front swing arm inserts into the slide groove from the primary limiting port and supports the back of the sliding member to limit the backward movement of the sliding member within the slide groove, thereby preventing the hinge bracket from folding downward. Therefore, during normal use of the wheelchair, even if the locking mechanism loses its lock on the folding arm due to an accident, the primary safety latch in the first front swing arm can still be used to prevent the hinge bracket from folding downward, further preventing accidental folding of the seat frame and potential injury to the user.

[0029] 4. During the unfolding of the backrest frame, the first and second front swing locking arms swing upwards synchronously with the backrest frame. During this process, the transition section of the secondary safety latch first enters the arc-shaped retraction slot in the second front swing locking arm, and under the action of the retraction block, pushes the secondary safety latch outwards, causing the rod head of the secondary safety latch to disengage from the slide groove in the slide rail, allowing the primary safety latch in the first front swing locking arm to smoothly insert into the primary limiting slot in the slide rail. Then, under the action of the retraction return spring, the rod head of the secondary safety latch inserts into the secondary limiting slot in the primary safety latch, achieving linkage limiting. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the structure of a linkage folding wheelchair after it is opened according to this application.

[0031] Figure 2 This is a schematic diagram of the structure of this application after the seat cushion and backrest have been removed and the structure has been opened.

[0032] Figure 3 This is a schematic diagram of the folded structure of this application after removing the seat cushion and backrest.

[0033] Figure 4This is a schematic diagram to show the structure between the folding arm and the switch / lock mechanism.

[0034] Figure 5 This is a cross-sectional view of the switch / lock component in this application.

[0035] Figure 6 This is a diagram illustrating the locked state between the backrest frame and the seat frame after the backrest frame has been unfolded.

[0036] Figure 7 This is a schematic diagram of the backrest frame after it has been unfolded in this application.

[0037] Figure 8 This is to demonstrate the specific installation structure of the secondary safety latch.

[0038] Explanation of reference numerals in the attached figures:

[0039] 1. Car chassis frame; 11. Wheel; 12. Drive motor; 2. Seat frame; 21. Seat cushion; 22. Slide rail; 221. Primary limit port; 23. Sliding component; 24. Secondary safety latch; 241. Rod head; 242. Rod body; 243. Transition part; 25. Rod sleeve; 26. Retracting rod return spring; 27. First limit component; 28. Second limit component; 3. Backrest frame; 31. Backrest cushion; 32. Small swing arm; 33. First front swing locking arm; 34. Primary safety latch; 35. Secondary safety latch 36. Limiting port; 37. Second front swing locking arm; 38. Arc-shaped retraction port; 4. Retraction block; 5. Handrail; 6. Support rod; 7. Foot pedal; 8. Hinge bracket; 9. Fork arm; 10. Folding arm; 11. First support arm; 12. Second support arm; 13. Lock hole; 14. Switch lock; 15. Housing; 16. Latch; 17. Latch track; 18. Button; 19. Second return spring; 20. Unlocking head; 10. Unlocking hole; 11. Unlocking ramp. Detailed Implementation

[0040] The following is in conjunction with the appendix Figure 1-8 This application will be described in further detail.

[0041] This application discloses a linkage folding wheelchair.

[0042] Reference Figure 1 A type of interconnected folding wheelchair includes a base frame 1, a seat frame 2, a backrest frame 3, armrests 4, and footrests 5.

[0043] Armrests 4 are installed on the left and right sides of the backrest frame 3. Wheels 11 are installed at the bottom of the chassis frame 1, and a drive motor 12 is installed on the rear wheel 11 to provide driving force for electric drive. A footrest 5 is installed on the front of the chassis frame 1 and is hinged to it, allowing it to be folded upwards or unfolded downwards. In this embodiment, a seat cushion 21 is installed on the top of the seat frame 2, and a backrest cushion 31 is installed inside the backrest frame 3.

[0044] Reference Figure 2 and Figure 3 The seat frame 2 is mounted on the vehicle underframe 1 via the hinge bracket 6, and the hinge bracket 6 is arranged on the left and right sides, so that the seat frame 2 can be raised and unfolded or folded down via the hinge bracket 6.

[0045] Reference Figure 2 Specifically, the articulated fork bracket 6 includes two intersecting and hinged fork arms 61. The two front ends of each fork arm 61 are hinged to the chassis frame 1 and the seat frame 2, respectively. The two opposite ends of each fork arm 61 are hinged to sliding members 23, which are horizontally mounted on the chassis frame 1 and the seat frame 2, respectively. When the articulated fork bracket 6 is extended, it causes the seat frame 2 to gradually rise, thus lifting and unfolding the seat frame 2. Similarly, when the articulated fork bracket 6 is folded, it causes the seat frame 2 to gradually lower, thus folding and retracting the seat frame 2, thereby enabling the seat frame 2 to be raised and unfolded or folded and retracted.

[0046] Specifically, in this embodiment, the inner sides of both the left and right sides of the vehicle underframe 1 are provided with sliding grooves, which extend horizontally. The lower sliding member 23 slides directly within the sliding groove in the vehicle underframe 1. The inner sides of both the left and right sides of the seat frame 2 are fixedly installed with slide rails 22. The slide rails 22 are horizontally positioned, and grooves are formed inside the slide rails 22. The upper sliding member 23 slides directly within the groove in the slide rail 22. In this embodiment, the upper sliding member 23 is a roller.

[0047] Reference Figure 2 In this embodiment, small swing arms 32 are fixedly installed on both sides of the bottom of the front side of the backrest frame 3. The backrest frame 3 is rotatably installed on the seat frame 2 through the two small swing arms 32, so that the backrest frame 3 can be flipped forward and folded or flipped backward and unfolded.

[0048] Reference Figure 2Two sets of folding arms 7 are installed between the underbody frame 1 and the backrest frame 3. The seat frame 2 and the backrest frame 3 are linked by the folding arms 7. When the folding arms 7 are unfolded, they cause the backrest frame 3 to flip backward and unfold, while simultaneously causing the seat frame 2 to rise and unfold. When the folding arms 7 are folded, they cause the backrest frame 3 to flip forward and fold, while simultaneously causing the seat frame 2 to fold downward and retract. A switch lock 8 is installed between the two sets of folding arms 7 to lock the folding arms 7 after they are unfolded.

[0049] Reference Figure 2 and Figure 3 When the wheelchair needs to be folded, the lock on the folding arm 7 is released, causing the folding arm 7 to fold downwards. At this time, driven by the hinge bracket 6, the seat frame 2 folds downwards; simultaneously, dragged by the folding arm 7, the backrest frame 3, along with the armrests 4, flips forward and folds up, forming a linked folding mechanism. When the wheelchair needs to be used, the folding arm 7 is unfolded. At this time, driven by the hinge bracket 6, the seat frame 2 rises and unfolds; simultaneously, dragged by the folding arm 7, the backrest frame 3, along with the armrests 4, flips backward and unfolds. After the folding arm 7 is unfolded, the lock on the switch 8 locks it in place.

[0050] Reference Figure 2 and Figure 4 Specifically, the folding arm 7 includes a first arm 71 and a second arm 72 that are rotatably connected to each other. The first arm 71 is located on the inner side, and the second arm 72 is located on the outer side. The end of the first arm 71 away from the second arm 72 is rotatably connected to the vehicle bottom frame 1, and the end of the second arm 72 away from the first arm 71 is fixedly connected to the backrest frame 3. During the folding process, the first arm 71 and the second arm 72 fold backward.

[0051] Reference Figure 4 and 5 Correspondingly, the switch lock 8 includes a housing 81, a latch 82, a first return spring 83, and a button 86. Latch cylinders 84 are inserted and fixed at both ends inside the housing 81, and the interior of the latch cylinders 84 is a latch channel 85. The latch 82 is slidably installed within the latch channel 85, and its end slidably passes through the first support arm 71. The first return spring 83 is installed in the latch channel 85 and pushes outward against the latch 82. Correspondingly, the second support arm 72 has a locking hole 73 for the latch 82 to pop out and lock when the folding arm 7 is unfolded.

[0052] Reference Figure 5The button 86 is pressable and slidably mounted on the outside of the housing 81, and a second return spring 87 is installed between the button 86 and the housing 81 to pop up the button 86 for reset. The button 86 is provided with two unlocking heads 88, and correspondingly, the latch 82 is provided with an unlocking hole 89. The inner side wall of the unlocking hole 89 is an unlocking slope 810. The two unlocking heads 88 slide against the unlocking slope 810 in the two latches 82 respectively, so that when the button 86 is pressed, it can press the latch 82 inward through the unlocking heads 88 and the unlocking slope 810.

[0053] Reference Figure 4 and Figure 5 When it is necessary to unlock the folding arm 7, press button 86. The unlocking head 88 in button 86 presses the latch 82 inward along the unlocking slope 810, causing the latch 82 to disengage from the lock hole 73 and unlock. Similarly, when the folding arm 7 is unfolded, under the action of the first return spring 83, the latch 82 pops out and inserts into the lock hole 73 to lock the first arm 71 and the second arm 72, thereby achieving locking after the folding arm 7 is unfolded.

[0054] Reference Figure 6 and Figure 7 In this embodiment, a primary limiting opening 221 is provided at the bottom of the slide rail 22 in the seat frame 2. The primary limiting opening 221 extends through the slide groove in the slide rail 22 and through the top of the slide rail 22. Correspondingly, a first front swing locking arm 33 is formed at the front end of the small swing arm 32. A primary safety latch 34 extends upward from the end of the first front swing locking arm 33 away from the backrest frame 3. During the unfolding process of the backrest frame 3, the primary safety latch 34 in the first front swing locking arm 33 is inserted into the slide groove from the primary limiting opening 221 and backs against the back side of the sliding member 23.

[0055] During the unfolding of the backrest frame 3, the first-level safety latch 34 in the first front swing locking arm 33 inserts into the slide groove from the first-level limiting port 221 and supports the back of the sliding member 23 to limit the backward movement of the sliding member 23 in the slide groove, thereby preventing the hinge bracket 6 from folding downward. Therefore, during normal use of the wheelchair, even if the locking mechanism loses its lock on the folding arm 7 due to an accident, the first-level safety latch 34 in the first front swing locking arm 33 can still be used to limit the downward folding of the hinge bracket 6, further preventing the seat frame 2 from folding unexpectedly and causing injury to the user.

[0056] Reference Figure 6 and Figure 7The primary safety latch 34 has a secondary limiting port 35 on its side. Correspondingly, secondary safety latches 24 are installed on both the left and right sides of the seat frame 2. After the backrest frame 3 is unfolded, the secondary safety latches 24 pass through the seat frame 2 and are inserted into the secondary limiting ports 35 in the primary safety latch 34. The secondary safety latches 24 are used to connect the primary safety latch 34 and the seat frame 2 during normal use of the wheelchair, thereby further improving the limiting stability of the limiting components.

[0057] Reference Figure 8 Specifically, the secondary safety latch 24 includes a rod head 241 and a rod body 242, with a gradually tapering transition portion 243 formed between the rod head 241 and the rod body 242. A rod sleeve 25 is fixedly installed on the side of the chair frame 2 at the position of the slide rail 22. The rod body 242 of the secondary safety latch 24 is inserted into the rod sleeve 25, and the rod body 242 passes through the chair frame 2 and the slide rail 22, extending into a groove in the slide rail 22. A retraction return spring 26 is installed inside the rod sleeve 25, and the retraction return spring 26, as described by the first limiting member 27, is sleeved on the rod body 242. A first limiting member 27 and a second limiting member 28 are respectively installed at both ends of the retraction return spring 26. The first limiting member 27 is located on the outer side and is fixedly connected to the rod sleeve 25. The second limiting member 28 is arranged on the inner side, and is fixedly connected to the retraction spring 26. The second limiting member 28 is inserted into the strip groove in the rod body 242.

[0058] Correspondingly, a second front swing arm 36 is also installed on the first front swing arm 33. The top of the front end of the second front swing arm 36 is provided with an arc-shaped retraction opening 37. Retraction blocks 38 are formed on both the front and rear sides of the arc-shaped retraction opening 37. The retraction blocks 38 gradually increase in size from top to bottom on the outward side and then gradually decrease in size to transition to the side of the second front swing arm 36.

[0059] Reference Figure 6 , 7 8. During the unfolding of the backrest frame 3, the first front swing locking arm 33 and the second front swing locking arm 36 swing upward synchronously with the backrest frame 3. During this process, the transition part 243 in the secondary safety latch 24 first enters the arc-shaped retraction port 37 in the second front swing locking arm 36, and under the action of the retraction block 38, pushes the secondary safety latch 24 outward, causing the rod head 241 in the secondary safety latch 24 to disengage from the slide groove in the slide rail 22, so that the primary safety latch 34 in the first front swing locking arm 33 can smoothly insert into the primary limiting port 221 in the slide rail 22. Then, under the action of the retraction return spring 26, the rod head 241 in the secondary safety latch 24 inserts into the secondary limiting port 35 in the primary safety latch 34 to achieve linkage limiting.

[0060] Reference Figure 2The armrest 4 is rotatably mounted on the backrest frame 3. The bottom of the armrest 4 is connected to the seat frame 2 via a support rod 41, and both ends of the support rod 41 are rotatably connected to the armrest 4 and the seat frame 2, allowing the armrest 4 to fold along with the backrest frame 3 during folding. Simultaneously, when the wheelchair is unfolded and in normal use, the support rod 41 further enhances the structural strength of the armrest 4.

[0061] The implementation principle is as follows:

[0062] When the wheelchair needs to be folded, press button 86 in the unlocking mechanism to release the lock on the folding arm 7. Pull the unlocking mechanism backward to fold the folding arm 7 backward. At this time, the seat frame 2 folds downward under the action of the hinge bracket 6; simultaneously, the backrest frame 3, along with the armrests 4, flips forward and folds up under the drag of the folding arm 7, forming a linked folding mechanism. In addition, rotate the footrest 5 upward to fold it up, completing the folding of the wheelchair.

[0063] When the wheelchair is needed, the footrest 5 is lowered by rotating it downwards. Then, the folding arm 7 is unfolded. At this time, driven by the hinge bracket 6, the seat frame 2 is lifted and unfolded; simultaneously, dragged by the folding arm 7, the backrest frame 3 and armrests 4 are flipped backwards and unfolded. After the folding arm 7 is unfolded, the latch 82 in the switch unlocking mechanism pops out and inserts into the locking hole 73 on the second arm 72 of the folding arm 7, thereby locking the first arm 71 and the second arm 72 of the folding arm 7, thus achieving locking after the folding arm 7 is unfolded.

[0064] Simultaneously, during the unfolding of the backrest frame 3, the first front swing locking arm 33 and the second front swing locking arm 36 on the backrest frame 3 swing upward synchronously with the backrest frame 3, allowing the first-level safety latch 34 in the first front swing locking arm 33 to smoothly insert into the first-level limiting port 221 in the slide rail 22 for first-level limiting. Then, the rod head 241 in the second-level safety latch 24 inserts into the second-level limiting port 35 in the first-level safety latch 34 for second-level limiting, thus achieving linkage limiting. This ensures that even if the locking mechanism loses its lock on the folding arm 7 due to an accident during normal wheelchair use, the two-level limiting mechanism still provides protection, further preventing accidental folding of the seat frame 2 and potential injury to the user.

[0065] The above are all preferred embodiments of the present application, and are not intended to limit the scope of protection of the present application. Therefore, any equivalent changes made based on the structure, shape, and principle of the present application should be included in the scope of protection of the present application.

Claims

1. A linkage folding wheelchair, characterized in that: The system includes a chassis frame (1), a seat frame (2), a backrest frame (3), and armrests (4). The seat frame (2) is mounted on the chassis frame (1) via a hinge bracket (6) to be raised and unfolded or folded down. The bottom of the backrest frame (3) is rotatably mounted on the seat frame (2), and the armrests (4) are mounted on both sides of the backrest frame (3). A folding arm (7) is installed between the chassis frame (1) and the backrest frame (3). The seat frame (2) and the backrest frame (3) are linked by the folding arm (7). When the folding arm (7) is unfolded, it causes the backrest frame (3) to flip backward and unfold, while simultaneously causing the seat frame (2) to be raised and unfolded. When the folding arm (7) is folded, it causes the backrest frame (3) to flip forward and fold, while simultaneously causing the seat frame (2) to fold down and unfold. A switch lock (8) is installed between the two sets of folding arms (7) to lock the folding arm (7) after it is unfolded. The hinged fork bracket (6) includes two intersecting hinged fork arms (61), and the two ends of the two fork arms (61) on one side are respectively hinged to the vehicle underframe (1) and the seat frame (2), and the two ends of the two fork arms (61) on the other side are each hinged to a slider (23), and the two sliders (23) are respectively slidably mounted on the vehicle underframe (1) and the seat frame (2) in the horizontal direction; The top sliding member (23) in the hinge bracket (6) is slidably installed on the seat frame (2) via the slide rail (22). The bottom of the slide rail (22) is provided with a first-level limiting port (221). The left and right sides of the bottom front side of the backrest frame (3) are equipped with first-level front swing locking arms (33). The first-level safety latch (34) extends upward from the end of the first-level front swing locking arm (33) away from the backrest frame (3). During the unfolding process of the backrest frame (3), the first-level safety latch (34) in the first-level front swing locking arm (33) is inserted into the slide groove from the first-level limiting port (221) and back supported on the back side of the sliding member (23). A secondary safety latch (24) is installed on both the left and right sides of the seat frame (2). The secondary safety latch (24) includes a rod head (241) and a rod body (242), and a gradually narrowing transition part (23) is formed between the rod head (241) and the rod body (242). A rod sleeve (25) is fixedly installed on the side of the seat frame (2) at the position of the slide rail (22). The rod body (242) of the secondary safety latch (24) is inserted into the rod sleeve (25), and the rod body (242) passes through the seat frame (2) and the slide rail (22) and extends into the slide groove. A rod return spring (26) is installed in the rod sleeve (25), and the rod return spring (26) is sleeved on the rod body (241). 42); The two ends of the retraction spring (26) are respectively equipped with a first limiting member (27) and a second limiting member (28). The first limiting member (27) is arranged on the outer side and fixedly connected to the sleeve (25); the second limiting member (28) is arranged on the inner side and installed on the rod body (242); a second front swing locking arm (36) is also installed on the first front swing locking arm (33). The top of the front end of the second front swing locking arm (36) is provided with an arc-shaped retraction opening (37). Retraction blocks (38) are formed on both the front and rear sides of the arc-shaped retraction opening (37). The retraction blocks (38) on the outer side gradually increase in size from top to bottom and then gradually decrease in size to transition to the side of the second front swing locking arm (36); The side of the primary safety latch (34) is provided with a secondary limiting port (35); and after the backrest frame (3) is unfolded, the secondary safety latch (24) passes through the seat frame (2) and is inserted into the secondary limiting port (35) in the primary safety latch (34).

2. A linkage folding wheelchair according to claim 1, characterized in that: The folding arm (7) includes a first arm (71) and a second arm (72) that are rotatably connected to each other. The end of the first arm (71) away from the second arm (72) is rotatably connected to the vehicle bottom frame (1), and the end of the second arm (72) away from the first arm (71) is fixedly connected to the backrest frame (3). During the folding process, the first arm (71) and the second arm (72) fold backward.

3. A linkage folding wheelchair according to claim 2, characterized in that: The folding arm (7) comprises at least two sets, and a switch lock (8) is installed between the two sets of folding arms (7) for locking them; the switch lock (8) comprises a housing (81), a latch (82), a first return spring (83), and a button (86); latch channels (85) are formed at both the left and right ends inside the housing (81), and the latch (82) is slidably installed in the latch channel (85); the first return spring (83) is installed in the latch channel (85), and the first return spring (83) pushes outward against the latch (82); the button (86) is pressable and slidably installed in the housing (81). Outside the housing (81), a second return spring (87) is installed between the button (86) and the housing (81); the button (86) is provided with two unlocking heads (88), the latch (82) is provided with an unlocking hole (89), the inner side wall of the unlocking hole (89) is an unlocking slope (810), and the two unlocking heads (88) slide against the unlocking slope (810) in the two latches (82); the second arm (72) is provided with a locking hole (73), which is used for the latch (82) to pop out and lock when the folding arm (7) is unfolded.

4. A linkage folding wheelchair according to claim 1, characterized in that: The bottom of the armrest (4) is connected to the seat frame (2) via a support rod (41), and both ends of the support rod (41) are rotatably connected to the armrest (4) and the seat frame (2).

5. A linkage folding wheelchair according to claim 1, characterized in that: It also includes a foot pedal (5), which is mounted on the chassis frame (1) and can be flipped up and folded.

6. A linkage folding wheelchair according to claim 1, characterized in that: It also includes a seat cushion (21) installed in the seat frame (2) and a back cushion (31) installed in the backrest frame (3).

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