Collapsible knee scooter

Abstract

A retractable knee-mounted vehicle includes a front wheel unit, a head tube unit, a rear wheel unit, a locking unit, and a footrest unit. The front wheel unit includes a front wheel frame and a pair of front rollers. The front wheel frame has a front axle tube and a vertical tube. The head tube unit includes a sleeve and a connector that slidably fit onto the vertical tube. The rear wheel unit includes a rear wheel frame and a pair of rear rollers. The locking unit includes a first locking member that allows the sleeve to slide relative to the vertical tube and achieve positioning, and a second locking member that allows the rear wheel frame to pivot relative to the connector and achieve positioning. The footrest unit is mounted on the rear wheel unit. The overall configuration allows the rear wheel unit to easily switch between an extended and retracted state relative to the front wheel unit.

Description

Technical Field

[0001] This utility model relates to a walking aid device, and more particularly to an easily retractable knee-carrying vehicle. Background Technology

[0002] A foldable and stable single-leg walking aid (authorization notice number CN216102562U) is available, comprising an arched front wheel frame, a crossbeam, a rear wheel frame, a handrail support rod, and a footpad. A front roller is mounted on each side of the bottom end of the front wheel frame via a pivot, and the top of the front wheel frame engages with the front end of the crossbeam. The handrail support rod is connected to the top of the front wheel frame via a first folding joint. The rear wheel frame is connected to the rear of the crossbeam via a second folding joint, and a rear roller is mounted on each side of the bottom end of the rear wheel frame via a pivot. The height of the rear rollers is lower than the height of the top of the front wheel frame from the ground.

[0003] When the single-leg bicycle needs to be stored, the second folding joint is operated to rotate the rear wheel frame to one side of the crossbeam, making the rear wheel frame parallel to the crossbeam. The stored single-leg bicycle occupies less space and is easy to carry.

[0004] The applicant believes that the closing operation can be simplified, so an alternative closing structure is provided. Utility Model Content

[0005] The purpose of this invention is to provide a knee car that can solve the problem of existing lack of an easily retractable design.

[0006] This utility model relates to an easily foldable knee-mounted stroller, comprising a front wheel unit, a head tube unit mounted on the front wheel unit, a rear wheel unit connected to the head tube unit, a locking unit mounted on the head tube unit, and a foot pad unit mounted on the rear wheel unit. The front wheel unit includes a front wheel frame and a pair of front rollers. The front wheel frame has a front axle tube and a vertical tube intersecting and connected to the front axle tube. The vertical tube has at least one positioning hole. The front rollers are axled on the front axle tube. The head tube unit includes a sleeve that slidably fits onto the vertical tube and a connecting member intersecting and connected to the sleeve. The rear wheel unit is pivotally connected to the head tube unit and includes a rear wheel frame and a pair of rear rollers. The rear wheel frame has a rear... The rear axle tube and a rear connecting tube intersectingly connected to the rear axle tube, the rear connecting tube having an inner end pivotally connected to the connector and an outer end connected to the rear axle tube, the rear roller axle being mounted on the rear axle tube, the rear wheel unit being able to switch between an extended state and a retracted state relative to the front wheel unit, in the extended state the rear roller and the front roller have the maximum distance between them, in the retracted state the rear roller approaches the front roller, the locking unit includes a first locking member that allows the sleeve to slide relative to the vertical tube and be positioned, and a second locking member that allows the rear connecting tube to pivot relative to the connector and be positioned, the foot pad unit being mounted on the rear wheel frame of the rear wheel unit.

[0007] The easily foldable knee brace of this utility model includes a locking unit further comprising a positioning seat fixed to the connector, a slide block slidable relative to the positioning seat, a first elastic member mounted on the positioning seat, and a second elastic member mounted on the positioning seat. The slide block has a first actuating part that can actuate the first locking member and a second actuating part that can actuate the second locking member. Operating the slide block can actuate the first locking member through the first actuating part, causing the first locking member to disengage from the positioning hole. The slide block can also actuate the second locking member through the second actuating part, causing the second locking member to disengage from the inner end of the rear tube. The elastic force of the first elastic member provides the first locking member with a rebound capability towards the positioning hole after disengaging from the positioning hole. The elastic force of the second elastic member provides the second locking member with a rebound capability towards the inner end of the rear tube after disengaging from the inner end.

[0008] The easily foldable knee-mounted bicycle of this utility model has a first buckle hole and a second buckle hole at an angle to the first buckle hole on the inner end of the rear tube of the rear wheel unit. The positioning seat of the locking unit has at least one intermediate guide, a first guide located on one side of the intermediate guide along the transverse axis, and a second guide located on the other side of the intermediate guide along the transverse axis. The slide seat also has a guide portion that can slide relative to the intermediate guide and is arranged along a longitudinal axis perpendicular to the transverse axis. The first braking portion is disposed on one side of the guide portion and is in the shape of an oblique groove. The first braking portion can brake the first guide to slide. The second braking portion is disposed on the other side of the guide portion and is in the shape of an oblique groove. The second braking portion can brake the second guide to slide. The first braking portion and the second braking portion are mirror-symmetrical about the guide portion as the center line.

[0009] The easily foldable knee brace of this utility model includes a locking unit with a positioning seat having a first positioning plate and a second positioning plate spaced apart from the first positioning plate along the transverse axis. The first locking member has a first locking portion spaced apart from the first positioning plate, and the second locking member has a second locking portion spaced apart from the second positioning plate. The first elastic member is a compression spring with opposite ends positioned on the first positioning plate and the first locking portion, and the second elastic member is a compression spring with opposite ends positioned on the second positioning plate and the second locking portion.

[0010] The easily foldable knee cart of this utility model has a through hole in the connector of the head tube unit, and the locking unit also has an operating member connected to the slide. The operating member has an operating part located outside the connector, and an extension section connected to the operating part and the slide. The extension section is slidably inserted through the through hole.

[0011] The easily foldable knee-mounted vehicle of this utility model has a main body for the positioning seat of the locking unit. The main body has a U-shaped cross-section parallel to the longitudinal axis and has a base plate and two side plates that intersect and connect to the two sides of the base plate. The first positioning plate and the second positioning plate are connected to the base plate. There are two intermediate guide members, which are pin-shaped. Each side plate has two guide grooves located on both sides of the intermediate guide member along the transverse axis. The first guide member and the second guide member are pin-shaped and can slide along their corresponding guide grooves.

[0012] The easily foldable knee tram of this utility model has a front wheel unit with a vertical tube having a top end opposite to the front axle tube, and a locking hole provided at the top end. The easily foldable knee tram also includes a handle unit installed on the vertical tube and a positioning unit. The handle unit has an inner tube inserted into the vertical tube and a handle tube intersecting and connected to the inner tube. The inner tube has several upper adjustment holes spaced apart along the longitudinal axis. The positioning unit includes a fixing member fixed to the top end, a button pivotally connected to the fixing member, a pin driven by the button, and a return member providing the elastic force of the button. Operating the button can cause the pin to disengage relative to the locking hole and one of the upper adjustment holes corresponding to the locking hole. The elastic force of the return member provides the ability for the pin to re-engage with the locking hole after disengaging relative to the locking hole.

[0013] The easily foldable knee-mounted vehicle of this utility model includes an adjusting outer tube intersecting and connected to the rear tube assembly, and a knob installed on the adjusting outer tube. The foot pad unit includes a backrest and an adjusting inner tube connected to the backrest. The adjusting inner tube is adjustablely inserted into the adjusting outer tube and has several spaced-apart lower adjusting holes. The knob can be inserted into any one of the lower adjusting holes.

[0014] The beneficial effects of this utility model are as follows: by utilizing the vertical tube of the front wheel unit that can be slidably installed on the front wheel unit, and the first locking member of the locking unit that can make the sleeve relative to the vertical tube slide and be positioned, and the second locking member that can make the rear wheel frame relative to the connecting member pivot and be positioned, the rear wheel unit can be switched between the extended state and the retracted state relative to the front wheel unit, and the switching operation is quite easy. Attached Figure Description

[0015] Figure 1 This is a three-dimensional assembly diagram of an embodiment of the easily foldable knee stroller of this utility model, illustrating the knee stroller in the folded state;

[0016] Figure 2 This is an exploded perspective view of this embodiment;

[0017] Figure 3 yes Figure 2 A magnified view of a portion of the image;

[0018] Figure 4 This is a cross-sectional view of this embodiment;

[0019] Figure 5 yes Figure 4 A magnified view of a portion of the image;

[0020] Figure 6 This is an operational schematic diagram of this embodiment, illustrating the operation of a locking unit;

[0021] Figure 7 This is a schematic diagram of the unfolded state of the knee vehicle in this embodiment;

[0022] Figure 8 yes Figure 7 A magnified view of a portion of the image;

[0023] Figure 9 This is another operational schematic diagram of this embodiment, illustrating the operation of a button;

[0024] Figure 10 This is a perspective view of the unfolded embodiment, illustrating the knee vehicle in its unfolded state. Detailed Implementation

[0025] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0026] See Figures 1 to 3 The present invention relates to an easily foldable knee-mounted bicycle, comprising a front wheel unit 10, a head tube unit 20 connected to the front wheel unit 10, a rear wheel unit 30 connected to the head tube unit 20, a locking unit 40 mounted on the head tube unit 20, a foot pad unit 50 mounted on the rear wheel unit 30, a handlebar unit 60 mounted on the front wheel unit 10, and a positioning unit 70.

[0027] The front wheel unit 10 includes a front wheel frame 11 and a pair of front rollers 12. The front wheel frame 11 has a front axle tube 111 and a vertical tube 112 intersecting and connected to the front axle tube 111. The vertical tube 112 has a top end portion 113 opposite to the front axle tube 111, two positioning holes 114 between the top end portion 113 and the front axle tube 111, and a locking hole 115 provided at the top end portion 113. The front rollers 12 are axled at both ends of the front axle tube 111.

[0028] The front tube unit 20 is slidably mounted on the front wheel unit 10 and includes a sleeve 21 that is slidably fitted onto the vertical tube 112, and a connector 22 that intersects and connects to the sleeve 21. The connector 22 is hollow and has a through hole 221 at the top.

[0029] The rear wheel unit 30 is pivotally connected to the head tube unit 20 and includes a rear wheel carrier 31, a pair of rear rollers 32, an adjusting outer tube 33, and a knob 34 mounted on the adjusting outer tube 33. The rear wheel carrier 31 has a rear axle tube 311 and a rear connecting tube 312 intersectingly connected to the rear axle tube 311. The rear connecting tube 312 has an inner end 313 rotatably pivotally connected to the connector 22 and an outer end 314 connected to the rear axle tube 311. The inner end 313 has a first fastening hole 315 and a second fastening hole 316 angled to the first fastening hole 315. The rear rollers 32 are axled on the rear axle tube 311.

[0030] Coordination Figure 5 The locking unit 40 includes a positioning seat 41 fixed to the connector 22, a slide 42 slidable relative to the positioning seat 41, a first locking member 43 slidably mounted on the positioning seat 41, a second locking member 44 slidably mounted on the positioning seat 41, a first elastic member 45 mounted on the positioning seat 41 and the first locking member 43, a second elastic member 46 mounted on the positioning seat 41 and the second locking member 43, and an operating member 47 connected to the slide 42.

[0031] The positioning base 41 has a main body 411, a first positioning plate 412 connected to the main body 411, a second positioning plate 413 spaced apart from the first positioning plate 412 along the transverse axis X, two pin-shaped intermediate guide members 414, a pin-shaped first guide member 415 located on one side of the intermediate guide member 414 along the transverse axis X, and a pin-shaped second guide member 416 located on the other side of the intermediate guide member 414 along the transverse axis X. The main body 411 has a U-shaped cross-section parallel to the longitudinal axis Z and has a base plate 417 and two side plates 418 intersecting and connected to the two side edges of the base plate 417. The base plate 417 has an opening 419. Each side plate 418 has two guide grooves 418' located on both sides of the middle guide member 414 along the transverse axis X, and the first guide member 415 and the second guide member 416 can slide along their respective guide grooves 418'.

[0032] The slide block 42 is plate-shaped and has a guide portion 421 that can slide relative to the intermediate guide member 414 and is arranged along the longitudinal axis Z, a first actuating portion 422 that can be linked to the first locking member 43, and a second actuating portion 423 that can be linked to the second locking member 44. The first actuating portion 422 is disposed on one side of the guide portion 421 and is shaped like an inclined groove, and the first actuating portion 422 can slide relative to the first guide member 415. The second actuating portion 423 is disposed on the other side of the guide portion 421 and is shaped like an inclined groove, and the second actuating portion 423 can slide relative to the second guide member 416. The first actuating portion 422 and the second actuating portion 423 are mirror-symmetrical about the guide portion 421 as the center line.

[0033] The first locking member 43 is rod-shaped and has a first linkage end 431 pivotally connected to the first guide member 415, a first locking end 432 disposed opposite to the first linkage end 431 along the transverse axis X, and a first locking portion 433 disposed inside the first locking end 432 and spaced apart from the first positioning plate 412.

[0034] The second locking member 44 is rod-shaped and has a second linkage end 441 pivotally connected to the second guide member 416, a second locking end 442 disposed opposite to the second linkage end 441 along the transverse axis X, and a second locking portion 443 disposed inside the second locking end 442 and spaced apart from the second positioning plate 413.

[0035] The first elastic element 45 is a compression spring, and its two opposite ends are respectively positioned on the first positioning plate 412 and the first locking part 433.

[0036] The second elastic element 46 is a compression spring, and its two opposite ends are respectively positioned on the second positioning plate 413 and the second locking part 443.

[0037] The operating member 47 is connected to the slide 42 and has an operating part 471 located outside the connector 22, and an extension 472 connecting the operating part 471 and the slide 42. The extension 472 is slidably inserted through the through hole 221.

[0038] The foot pad unit 50 is mounted on the rear wheel unit 30 and includes a cushion 51 and an adjusting inner tube 52 connected to the cushion 51. The adjusting inner tube 52 is adjustablely inserted into the adjusting outer tube 33 and has several spaced-apart lower adjusting holes 521. The knob 34 can be inserted into any one of the lower adjusting holes 521.

[0039] Coordination Figure 5The handle unit 60 has an inner tube 61 inserted inside the vertical tube 112, and a handle tube 62 that intersects and connects to the inner tube 61. The inner tube 61 has several upper adjustment holes 611 that are spaced Z apart along the longitudinal axis.

[0040] Coordination Figure 5 The positioning unit 70 includes a fixing member 71 fixed to the top end 113 of the vertical pipe 112, a button 72 pivotally connected to the fixing member 71, a pin 73 actuated by the button 72, and a return member 74 providing spring force to the button 72. See Figure 9 Operating the button 72 can disengage the pin 73 relative to the latch 115 and one of the upper adjustment holes 611 corresponding to the latch 115. The return member 74 is a compression spring, the elasticity of which provides the pin 73 with the ability to re-engage with the latch 115 after disengaging from the latch 115.

[0041] To further understand the effects of the combination of the components of this utility model, the technical means employed, and the expected results, the following explanation will be provided, which will hopefully lead to a deeper and more specific understanding of this utility model.

[0042] like Figure 1 , Figure 4 and Figure 5 The diagram shows the easily foldable knee tram of this invention in its folded state. At this time, the sleeve 21 approaches the top end 113 of the vertical tube 112, and the locking unit 40 positions the sleeve 21 relative to the vertical tube 112. Specifically, the elastic force of the first elastic member 45 allows the first locking member 43 to pass through the positioning hole 114 closer to the top end 113, and the elastic force of the second elastic member 46 allows the second locking member 44 to pass through the first buckle hole 315 of the rear connecting tube 312. The rear connecting tube 312 is pivotally connected to the connecting member 22 in an L-shape, and the rear connecting tube 312 is substantially parallel to the vertical tube 112. In the folded state, the rear roller 32 approaches the front roller 12, effectively reducing the length corresponding to the horizontal axis X and decreasing the overall volume.

[0043] For example Figure 5 As shown, the inner tube 61 of the handle unit 60 is retracted into the vertical tube 112, and the handle tube 62 is brought close to the top end 113. At this time, the elasticity of the return member 74 provides the pin 73 with a fastening relative to one of the upper adjustment holes 611, which enables the handle unit 60 to be positioned relative to the vertical tube 112, effectively reducing the height corresponding to the longitudinal axis Z and reducing the overall volume.

[0044] like Figure 6As indicated by the arrow, when the operating member 47 of the locking unit 40 moves downward, the operating member 47 also moves the slide 42 downward. The slide 42 can actuate the first locking member 43 through the first actuating part 422, causing the first locking member 43 to disengage from the corresponding positioning hole 114 (the first elastic member 45 is compressed and contains a release force). At the same time, the downward movement of the slide 42 can also actuate the second locking member 44 through the second actuating part 423, causing the second locking member 44 to disengage from the first latching hole 315 of the rear connecting pipe 312 (the second elastic member 46 is compressed and contains a release force).

[0045] Next, the operator can move the entire head tube unit 20 down along the vertical tube 112 and pivot the rear tube 312 of the rear wheel unit 30 relative to the connector 22. When the head tube unit 20 approaches the front axle tube 111, the release force of the first elastic member 45 allows the first locking member 43 to engage with the positioning hole 114 approaching the front axle tube 111, and the sleeve 21 is then positioned relative to the vertical tube 112. Furthermore, when the second locking hole 316 of the rear tube 312 corresponds to the second locking member 44, the release force of the second elastic member 46 allows the second locking member 44 to engage with the second locking hole 316, and the rear wheel frame 31 is positioned relative to the connector 22. This will result in... Figure 7 , Figure 8 and Figure 10 As shown, the easily foldable knee cart of this utility model is operated in the unfolded state, and in the unfolded state, the maximum distance is generated between the rear roller 32 and the front roller 12.

[0046] For example Figure 9 As shown, by operating the button 72 of the positioning unit 70, the pin 73 is moved out of the locking hole 115 and one of the upper adjustment holes 611. Then, the inner tube 61 of the handle unit 60 is extended outward relative to the vertical tube 112 by the working length, and the handle tube 62 is moved away from the top end 113 until the other upper adjustment hole 611 corresponds to the pin 73. When the pressure on the button 72 is released, the elasticity of the return member 74 allows the pin 73 to be inserted back into the locking hole 115 and the upper adjustment hole 611, thus positioning the handle unit 60 relative to the vertical tube 112 and adjusting the working height of the handle tube 62.

[0047] like Figure 6As indicated by the arrow, when the easily foldable knee cart of this invention is operated in the unfolded state, and the operating member 47 of the locking unit 40 is moved downward, the operating member 47 moves the slide 42 downward. The slide 42 can then engage the first locking member 43 via the first braking part 422, causing the first locking member 43 to disengage from the corresponding positioning hole 114 (the first elastic member 45 is compressed and contains a release force). Simultaneously, the downward movement of the slide 42 can also engage the second locking member 44 via the second braking part 423, causing the second locking member 44 to disengage from the second buckle hole 316 of the rear connecting pipe 312 (the second elastic member 46 is compressed and contains a release force). This allows the easily foldable knee cart of this invention to be operated from the unfolded state to the folded state (see...). Figure 1 , Figure 4 (State).

[0048] Therefore, the easily foldable knee cart of this utility model utilizes the fact that the head tube unit 30 can be slidably installed on the vertical tube 112 of the front wheel unit 10, and the first locking member 43 of the locking unit 40 can make the sleeve 21 slide relative to the vertical tube 112 to achieve positioning, and the second locking member 44 can make the rear wheel frame 31 pivot relative to the connecting member 22 to achieve positioning. This allows the rear wheel unit 30 to switch between the unfolded and folded states relative to the front wheel unit 10. It can not only be folded down to reduce the volume in a timely manner to facilitate storage, transportation, and packaging, but also unfolded for use in a timely manner. Moreover, the switching operation is quite easy.

[0049] In conclusion, the foldable knee cart of this utility model has a simple overall structure and is easy to manufacture and assemble, and it can indeed achieve the purpose of this utility model.

Claims

1. A foldable knee-mounted stroller, comprising a front wheel unit, a head tube unit mounted on the front wheel unit, a rear wheel unit connected to the head tube unit, a locking unit mounted on the head tube unit, and a foot pad unit mounted on the rear wheel unit, characterized in that: The front wheel unit includes a front wheel frame and a pair of front rollers. The front wheel frame has a front axle tube and a vertical tube intersecting and connected to the front axle tube. The vertical tube has at least one positioning hole. The front rollers are axled on the front axle tube. The head tube unit includes a sleeve that can be slidably fitted onto the vertical tube, and a connector that intersects and connects to the sleeve. The rear wheel unit is pivotally connected to the front tube unit and includes a rear wheel frame and a pair of rear rollers. The rear wheel frame has a rear axle tube and a rear connecting tube that intersectes and connects to the rear axle tube. The rear connecting tube has an inner end that is rotatably pivotally connected to the connector and an outer end that is connected to the rear axle tube. The rear rollers are axled on the rear axle tube. The rear wheel unit can switch between an extended state and a retracted state relative to the front wheel unit. In the extended state, the rear rollers are at their maximum distance from the front rollers. In the retracted state, the rear rollers are closer to the front rollers. The locking unit includes a first locking member that enables the sleeve to slide relative to the vertical pipe and then be positioned, and a second locking member that enables the rear pipe to pivot relative to the connector and then be positioned. The foot pad unit is mounted on the rear wheel frame of the rear wheel unit.

2. The easily foldable knee rest according to claim 1, characterized in that: The locking unit further includes a positioning seat fixed to the connector, a slide block slidable relative to the positioning seat, a first elastic member mounted on the positioning seat, and a second elastic member mounted on the positioning seat. The slide block has a first actuating part that can be linked to the first locking member and a second actuating part that can be linked to the second locking member. Operating the slide block can actuate the first locking member through the first actuating part and disengage the first locking member relative to the positioning hole. The slide block can also actuate the second locking member through the second actuating part and disengage the second locking member relative to the inner end of the rear tube. The elastic force of the first elastic member provides the first locking member with a spring-like ability to be inserted into the positioning hole after disengaging from the positioning hole. The elastic force of the second elastic member provides the second locking member with a spring-like ability to be fastened to the inner end after disengaging from the inner end of the rear tube.

3. The easily foldable knee rest according to claim 2, characterized in that: The inner end of the rear tube of the rear wheel unit has a first buckle hole and a second buckle hole set at an angle to the first buckle hole. The positioning seat of the locking unit has at least one intermediate guide, a first guide located on one side of the intermediate guide along the transverse axis, and a second guide located on the other side of the intermediate guide along the transverse axis. The slide also has a guide portion that can slide relative to the intermediate guide and is set along a longitudinal axis perpendicular to the transverse axis. The first braking portion is disposed on one side of the guide portion and is in the shape of an oblique groove. The first braking portion can brake the first guide to slide. The second braking portion is disposed on the other side of the guide portion and is in the shape of an oblique groove. The second braking portion can brake the second guide to slide. The first braking portion and the second braking portion are mirror-symmetrical about the guide portion as the center line.

4. The easily foldable knee rest according to claim 3, characterized in that: The positioning seat of the locking unit also has a first positioning plate and a second positioning plate spaced apart from the first positioning plate along the transverse axis. The first locking member has a first locking portion spaced apart from the first positioning plate, and the second locking member has a second locking portion spaced apart from the second positioning plate. The first elastic member is a compression spring with opposite ends positioned on the first positioning plate and the first locking portion, and the second elastic member is a compression spring with opposite ends positioned on the second positioning plate and the second locking portion.

5. The easily foldable knee rest according to claim 4, characterized in that: The connector of the head tube unit has a through hole, and the locking unit also has an operating member connected to the slide. The operating member has an operating part located outside the connector and an extension section connected to the operating part and the slide. The extension section is slidably inserted through the through hole.

6. The easily foldable knee cart according to claim 4, characterized in that: The positioning seat of the locking unit has a main body with a U-shaped cross-section parallel to the longitudinal axis and a base plate and two side plates that intersect and connect to the two sides of the base plate. The first positioning plate and the second positioning plate are connected to the base plate. There are two intermediate guide members in the shape of pins. Each side plate has two guide grooves located on both sides of the intermediate guide member along the transverse axis. The first guide member and the second guide member are in the shape of pins and can slide along their corresponding guide grooves.

7. The easily foldable knee rest according to claim 1, characterized in that: The front wheel unit's vertical tube has a top end opposite to the front axle tube, and a locking hole provided at the top end. The easily foldable knee-carrying vehicle also includes a handle unit mounted on the vertical tube and a positioning unit. The handle unit has an inner tube inserted inside the vertical tube and a handle tube intersecting and connected to the inner tube. The inner tube has several upper adjustment holes spaced apart along the longitudinal axis. The positioning unit includes a fixing member fixed to the top end, a button pivotally connected to the fixing member, a pin actuated by the button, and a return member providing the spring force of the button. Operating the button can cause the pin to disengage relative to the locking hole and one of the upper adjustment holes corresponding to the locking hole. The spring force of the return member provides the ability for the pin to re-engage with the locking hole after disengaging from it.

8. The easily foldable knee rest according to claim 1, characterized in that: The rear wheel unit also includes an adjusting outer tube that is intersectingly connected to the rear connecting tube, and a knob installed on the adjusting outer tube. The foot pad unit includes a backrest and an adjusting inner tube connected to the backrest. The adjusting inner tube is adjustablely inserted into the adjusting outer tube and has several spaced-apart lower adjusting holes. The knob can be inserted into any one of the lower adjusting holes.

Images