Trailer head unlocking device

Abstract

The utility model relates to a kind of trailer head unlocking device, it is applied to a trailer head and a wheelchair, the unlocking device has a wire control unlocking group, and using the wire control unlocking group has a fixed frame, a sliding pull rod and the structure of a selectively actuable lock catch toggle, so that the wire control unlocking group can be actuated by a wire rocker lever A cable to pull the sliding pull rod can complete the unlocking of the lock catch, with the effect that lock catch and unlocking are easy to operate, so that users can easily lock and unlock the trailer head, and has the effect of double safety protection, to avoid the trailer head in the process of travel arbitrary separation, effectively improve its security.

Description

Technical Field

[0001] This utility model relates to a trailer head unlocking device, which is mainly applied in the field of wheelchair technology. Background Technology

[0002] Wheelchairs are a common type of mobility aid, used by patients with lower limb weakness or injury who have difficulty moving. Traditional wheelchairs rely primarily on the user pushing the side wheels or a caregiver pushing from behind to move forward or backward. Because they depend mainly on human power, moving a wheelchair is extremely strenuous and the distance is limited. With technological advancements, wheelchairs have evolved from traditional human-powered wheelchairs to electric wheelchairs with their own power source. While electric wheelchairs offer advantages such as easier operation and longer travel distances, their electric drive system is complex and requires external batteries, resulting in greater weight and higher price. Furthermore, they present inconvenience in certain public places and indoor spaces. Additionally, users may become overly reliant on electric wheelchairs, losing opportunities for physical activity, and the wheelchair becomes unusable when the motor power is insufficient.

[0003] To address this, the industry has developed an external wheelchair consisting of a wheelchair, a docking mechanism, and a trailer hitch. When there is no power, or during indoor or short-distance travel, the wheelchair can be detached from the trailer hitch, allowing the user to operate the wheelchair manually in a traditional manner. In the detached state, the wheelchair can be easily folded away, saving space and allowing it to be stored in a car along with the detached trailer hitch. For long-distance travel or when effort is required, the trailer hitch can be attached to the front of the wheelchair for easy and quick movement.

[0004] However, existing external wheelchair trailers have the problem of not being able to automatically lock when docking with a wheelchair, and unlocking them after docking is also difficult. Even worse, the locking mechanism only has one layer of protection, which may cause it to accidentally separate due to bumps and collisions during movement, thus endangering the safety of movement. Further improvements are needed. Utility Model Content

[0005] The technical problem to be solved by this utility model is to provide a trailer head unlocking device that facilitates the user's operation of the docking and unlocking of the trailer head and wheelchair, and has an automatic locking function, which can effectively improve its operational convenience and practicality. At the same time, it can also prevent the trailer head from separating arbitrarily during travel through a double safety protection structure, effectively improving its travel safety and overcoming the shortcomings of the prior art.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: a trailer head unlocking device, which is applied between a trailer head and a wheelchair, wherein the trailer head has a docking seat, a hook rod is inserted through the docking seat, and the two ends of the hook rod slightly protrude from the side walls of the docking seat; the docking seat forms a snap-fit ​​groove; and the wheelchair has a connecting cover, the connecting cover has oblique snap-fit ​​grooves corresponding to the two ends of the hook rod; the connecting cover is provided with a locking rod corresponding to the snap-fit ​​groove, for selective unlocking of the connecting rod by an unlocking device. The shaft cover is locked or unlocked relative to the mating seat. The unlocking device consists of a wire-controlled unlocking assembly, which includes: a fixed frame, a sliding rod, and a locking lever. The fixed frame has two sides that can be fixed to the mating seat, and a pull cable passes through the fixed frame, which can be pulled by a wire rocker. The sliding rod is slidably disposed within the mating seat and can be moved between a lower locked position and an upper unlocked position by the pull cable. A spring-loaded storage mechanism is provided between the sliding rod and the mating seat. The sliding rod generates an elastic preload that automatically returns it to the lower locking position. The locking lever is pivotally mounted within the mating seat at a fulcrum. The sliding rod is linked to the locking lever via at least one pivotally mounted connecting rod assembly. The connecting rod assembly has an elongated elliptical groove at one end of the locking lever, allowing a pivot rod to pass through the groove and the top of the locking lever, enabling partial sliding within the groove. The locking lever has an L-shaped structure. The piece has a hook portion that moves into the corresponding snap-fit ​​groove, allowing the locking lever to rotate around the fulcrum. This allows the hook portion of the locking lever to selectively hook the locking rod embedded in the snap-fit ​​groove. The locking lever is also provided with at least one rotational torque spring, which allows the locking lever to generate a restoring force that automatically engages the locking rod. By operating the rocker arm to pull the cable, the sliding lever is moved to the upper unlock position, thereby actuating the linkage assembly to release the locking rod of the connecting cover by the hook portion of the locking lever.

[0007] Preferably, the wheelchair has a docking rod, a coupling cover is formed at the front end of the docking rod, and each side of the coupling cover has a corresponding side abutment. The oblique buckle groove is formed on the side abutments on both sides of the coupling cover. The locking rod spans the side abutments on both sides of the coupling cover. The trailer head is composed of a vehicle body upright. A handlebar is horizontally provided at the top of the vehicle body upright and a wheel is provided at the bottom. The docking seat is provided on a docking bushing pivotally provided on the vehicle body upright, and the line rocker is provided at one end of the handlebar.

[0008] Preferably, the docking seat has an internal mounting channel that passes through the buckle groove and extends vertically to the side of the wheelchair, allowing the locking lever to be pivotally mounted in the mounting channel using a pivot shaft. The docking seat also has a sliding channel that is substantially parallel to the mounting channel and extends vertically to the side. The sliding rod is slidably mounted in the sliding channel. The lower section of the sliding channel is connected to the mounting channel via a connecting channel, and the connecting rod assembly is located in the connecting channel.

[0009] Preferably, at least one locking groove is provided on each of the two side walls of the docking seat, and the two sides of the fixing frame can be fixed to the locking groove by at least one locking fastener.

[0010] Preferably, the sliding rod has an accommodating long groove, and the sliding rod has an interconnected half-shaft groove at the top of the accommodating long groove, through which a limiting shaft passes by the docking seat. The elastic storage member is disposed between the bottom end of the accommodating long groove of the sliding rod and the limiting shaft of the docking seat, so that the sliding rod slides downward and is restricted to the lower locking position.

[0011] Preferably, the locking rocker has a pivot hole, through which the locking rocker is pivoted onto the mating seat using the pivot shaft, serving as the fulcrum for the rotation of the locking rocker.

[0012] Preferably, the fixed frame of the wire-controlled unlocking assembly has a frame plate in front, the frame plate is provided with a safety lock assembly, and the safety lock assembly has a stop bar that slides through the frame plate, and the stop bar can slide between a stop position and a release position relative to the top edge of the sliding rod, so as to selectively restrict the sliding rod from being pulled upward.

[0013] Preferably, a compression spring and a slide cylinder are sequentially inserted through one end of the outer side of the frame plate and locked onto a knob. The slide cylinder and the knob respectively form a first cam portion and a second cam portion on their respective contact surfaces, so that the knob can move between a close position and a disengaged position relative to the slide cylinder, and the knob can move the stop rod to slide between the stop position and the release position relative to the top edge of the sliding rod.

[0014] Preferably, the first and second cam portions can be relatively fitted inclined surfaces.

[0015] The beneficial effects of this utility model are as follows: Through the aforementioned technical means, this invention utilizes the design of the wire-controlled unlocking group in the unlocking device, so that when the trailer head is connected to the wheelchair, the structure of the elongated elliptical groove of the connecting rod assembly and the rotating torque spring of the locking lever in the wire-controlled unlocking group can be used to automatically lock the locking rod of the connecting cover by the locking lever. At the same time, the locking lever can be unlocked by using the wire rocker arm of the wire-controlled unlocking group to pull the cable and pull the sliding rod. This has the effect of easy operation for locking and unlocking, which can effectively improve its practicality and further increase its added value and economic benefits.

[0016] The present invention will now be described in further detail with reference to the accompanying drawings. Attached Figure Description

[0017] Figure 1 This is a 3D rendering of the trailer head unlocking device of this creation.

[0018] Figure 2 This is a 3D exploded view of the trailer head unlocking device in this creation.

[0019] Figure 3 This is a three-dimensional schematic diagram of the docking seat in the trailer head unlocking device of this creation, viewed from below.

[0020] Figure 4 This is a three-dimensional schematic diagram of the docking seat in the trailer head unlocking device of this creation, viewed from above.

[0021] Figure 5 This is a side view of the trailer head unlocking device of this invention when it is assembled.

[0022] Figure 6 This is a side view of the trailer head unlocking device during the wheelchair docking and locking action.

[0023] Figure 7 This is a side view diagram of the trailer unlocking device after the wheelchair is docked and locked.

[0024] Figure 8 This is a side view of the trailer head unlocking device of this invention when the wheelchair is detached and unlocked. Detailed Implementation

[0025] This invention relates to a trailer unlocking device for external wheelchairs, such as... Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5As shown, it is used when a trailer head 10 selectively docks with a wheelchair 80 (only a partial docking mechanism is shown), wherein the wheelchair 80 has a docking rod 81, the front end of the docking rod 81 has a coupling cover 82, and each side of the coupling cover 82 has an opposing side abutment 83. Each side abutment 83 on both sides of the coupling cover 82 has a forward-opening oblique locking groove 86 near its top. A locking rod 88 is provided between the middle sections of the side abutments 83 on both sides of the coupling cover 82, so that the wheelchair 80 can be selectively connected to the trailer head 10 using the coupling cover 82 of the docking rod 81 (e.g., Figure 6 and Figure 7 (as shown);

[0026] The trailer head 10 is composed of a vehicle body upright 11 with a battery and a drive element. A handlebar 12 for directional control is horizontally mounted at the top of the upright 11, and a wheel 13 driven by the drive element is located at the bottom. A docking bushing 15 is pivotally mounted on the upright 11 near the wheel 13. The docking bushing 15 has a docking seat 20 for the aforementioned connecting cover 82 to close. A hook rod 21 is inserted near the top of the front edge of the docking seat 20, with both ends of the hook rod 21 slightly protruding from the side walls of the docking seat 20. A locking groove 22 is formed in the middle of the front side of the docking seat 20, and a locking latch 47 of an unlocking device 400 is located within the locking groove 22. This latch is used to allow the wheelchair 80 to selectively close the connecting cover 82 of the docking rod 81 onto the docking seat 20 of the trailer head 10 (e.g., when the wheelchair 80 is selectively closed with the connecting cover 82 of the docking rod 81 onto the docking seat 20 of the trailer head 10). Figure 6 As shown), the side abutments 83 on both sides of the coupling cover 82 can abut against the side walls of the mating seat 20, and the oblique buckle groove 86 and the locking rod 88 of the coupling cover 82 can be simultaneously engaged with the locking pry bar 47 (as shown) at both ends of the hook rod 21 and the locking groove 22 of the mating seat 20. Figure 7 As shown), the trailer head 10 is connected to the wheelchair 80, so that the wheelchair 80 can be moved by the trailer head 10.

[0027] The unique feature of this invention is that the unlocking device 400 consists of a single-line unlocking assembly 40 and a safety lock assembly 50, forming a double-locking protection, such as... Figures 2 to 5 As shown, the wire-controlled unlocking assembly 40 is mounted on the docking seat 20. The docking seat 20 has an internal mounting groove 23 that passes through the snap-fit ​​groove 22 and extends vertically to the side of the wheelchair 80. Figure 3 and Figure 4 As shown), the mating seat 20 has a sliding channel 24 that is substantially parallel to and extends vertically through the mounting channel 23. The lower section of the sliding channel 24 is connected to the mounting channel 23 via a connecting channel 240 (e.g., Figure 3 and Figure 4 (as shown);

[0028] The wire-controlled unlocking assembly 40 includes a fixed frame 41, a sliding rod 44, and the aforementioned selectively actuated latching pry bar 47. The fixed frame 41 has two opposing slots 201 on its sides that can be fitted into the side walls of the docking seat 20, respectively, for at least one locking fastener 412 to fix the fixed frame 41 to the docking seat 20. The sliding rod 44 slides within the sliding groove 24 of the docking seat 20, allowing it to slide between a lower latching position and an upper unlocking position. A corresponding locking mechanism is formed on the sliding rod 44. The sliding rod 44 has a long groove 441 parallel to the long axis of the sliding rod 44. The top of the long groove 441 has a half-shaft groove 442 that is interconnected with the sliding rod 44. A limiting shaft 443 is inserted through the docking seat 20 into the half-shaft groove 442 of the sliding rod 44, so that the sliding rod 44 slides downward and is restricted to the aforementioned lower locking position. An elastic storage member 45, such as a compression spring, is provided between the bottom end of the long groove 441 of the sliding rod 44 and the limiting shaft 443, so that the sliding rod 44 can generate an elastic preload that automatically returns to the lower locking position.

[0029] The bottom end of the sliding rod 44 actuates the locking lever 47 located in the mounting channel 23 via at least one pivotally mounted connecting rod assembly 46. Near the top end of the connecting rod assembly 46, an elongated elliptical groove 461 is formed, allowing a pivot rod 462 to pass through the elongated elliptical groove 461 of the connecting rod assembly 46 and the top end of the locking lever 47. The elongated elliptical groove 461 provides sufficient space for the connecting rod assembly 46 to actuate the locking lever 47, preventing jamming due to a dead point during actuation and improving the flexibility of the locking lever 47's movement. Furthermore, the locking lever... The rocker arm 47 is generally L-shaped, and its front end has a hook portion 471 corresponding to the latching groove 22 of the mating seat 20. A pivot hole 472 is formed in the middle of the bend of the rocker arm 47, allowing the rocker arm 47 to be pivotally inserted between the connecting channel 240 and the mounting groove 23 of the mating seat 20 via a pivot shaft 475. This allows the wire-controlled unlocking assembly 40 to slide up and down via the sliding rod 44, thereby actuating the rocker arm 47 through the connecting rod assembly 46, enabling the rocker arm 47 to be selectively engaged (e.g., ...). Figure 6 and Figure 7 (as shown) or release (as shown) Figure 8 (As shown) The locking rod 88 of the connecting cover 82 embedded in the buckle groove 22, and at least one rotational torque spring 48 is provided between the pivot shaft 475 and the two sides of the locking rocker 47, so that the locking rocker 47 can generate a restoring preload that causes the hook part 471 to automatically pull the locking rod 88 upward, and utilize the space of the long elliptical groove 461 of the connecting rod assembly 46 so that when the locking rocker 47 is partially pushed open, it will not cause the sliding pull rod 44 to move upward through the connecting rod assembly 46;

[0030] A cable 42 is threaded through the fixed frame 41. The cable 42 can be pulled upward by a line rocker arm 43 located on the aforementioned handlebar 12. The cable 42 can also be located at the top of the sliding lever 44, so that the sliding lever 44 can be moved to the unlocked position above by the cable 42 when the user operates the line rocker arm 43.

[0031] The safety lock assembly 50 is located on a frame plate 415 in front of the fixed frame 41. The safety lock assembly 50 has a stop bar 51 that slides through the frame plate 415. The height of the stop bar 51 at one end inside the frame plate 415 corresponds to the top edge of the locking position of the sliding pull rod 44 located below, so as to restrict the sliding pull rod 44 from being pulled upward by the cable 42. A compression spring 52 and a slide cylinder 55 are sequentially passed through the stop bar 51 at one end outside the frame plate 415, and it is locked to a knob 58. Furthermore, the sliding cylinder 55 and the knob 58 respectively form a first cam portion 56 and a second cam portion 59 on their respective contact surfaces. The first and second cam portions (56, 59) can be relative inclined surfaces or high and low teeth, so that the knob 58 can operate between a close position and a disengaged position relative to the sliding cylinder 55. Simultaneously, the knob 58 can operate the stop lever 51 to slide between a stop position and a release position relative to the top edge of the sliding lever 44. This constitutes a trailer head unlocking device that can automatically lock and has double protection.

[0032] In actual use, if the wheelchair 80 is not connected to the trailer head 10, such as Figure 1 and Figure 5 As shown, the sliding lever 44 of the wire-controlled unlocking assembly 40 is limited to the lower locking position by the limiting shaft 443 and the restoring preload of the elastic storage member 45. This allows the sliding lever 44 to drive the locking peg 47 through the linkage assembly 46, with the pivot shaft 475 as the fulcrum. The hook portion 471 of the locking peg 47 is slightly higher than the bottom edge of the locking groove 22 of the docking seat 20, in preparation for receiving the locking rod 88 of the connecting cover 82 of the wheelchair 80. The knob 58 of the safety lock assembly 50 is in the close position, so that the stop lever 51 synchronized with the knob 58 can limit the sliding lever 44 to the downward sliding stop position.

[0033] When the wheelchair 80 is closed with the coupling cover 82 of the coupling rod 81 onto the docking seat 20 of the trailer head 10, such as Figure 6 and Figure 7As shown, the coupling cover 82 can be hooked onto the two ends of the hook rod 21 of the docking seat 20 by the oblique buckle groove 86 of the side abutment pieces 83 on both sides. At the same time, the locking rod 88 in the middle section of the coupling cover 82 is embedded in the buckling groove 22 of the docking seat 20. When the locking rod 88 pushes against the front end of the locking rocker 47, the long elliptical groove 461 of the connecting rod assembly 46 has a margin of space, so that the locking rocker 47 can be partially pushed open without causing displacement of the sliding pull rod 44 through the connecting rod assembly 46. Thus, the locking rocker 47 can lock the locking rod 88 of the coupling cover 82 by the hook part 471, so that the wheelchair 80 can be selectively connected to the docking seat 20 of the trailer head 10 by the coupling cover 82 of the docking rod 81, and the docking of the trailer head 10 and the wheelchair 80 is completed.

[0034] Furthermore, when attempting to separate the trailer head 10 from the wheelchair 80, such as Figure 8 As shown, the user needs to rotate the knob 58 of the safety lock assembly 50 to the disengaged position, so that the knob 58 simultaneously actuates the stop lever 51 to the release position relative to the top edge of the sliding pull rod 44. Thus, when the user operates the cable rocker 43, the cable 42 can be actuated to pull the sliding pull rod 44 upward and simultaneously compress the elastic storage member 45. The sliding pull rod 44 can also drive the linkage assembly 46 to actuate the locking lever 47 with the pivot shaft 475 as the fulcrum. After the locking lever 47 rotates, the hook part 471 can release the locking rod 88 of the coupling cover 82, so that the locking rod 88 of the coupling cover 82 can disengage from the latching groove 22 of the docking seat 20, and the inclined latching groove 86 of the coupling cover 82 disengages from the hook rod 21 of the docking seat 20, thereby realizing the separation of the wheelchair 80 from the trailer head 10.

[0035] As can be seen from the foregoing composition and usage description, this invention utilizes the design of the unlocking device 400 having the wire-controlled unlocking group 40 and the safety lock group 50, so that when the trailer head 10 is docked with the wheelchair 80, the structure of the elongated elliptical groove 461 of the connecting rod assembly 46 and the rotating torque spring 48 of the locking lever 47 in the wire-controlled unlocking group 40 can be used to make the locking rod 88 of the connecting cover 82 automatically locked by the locking lever 47. At the same time, the wire rocker arm 43 of the wire-controlled unlocking group 40 can be used to actuate the cable 42 to pull the sliding rod 44 to complete the unlocking of the locking lever 47, thus having the function of easy locking and unlocking.

[0036] Furthermore, the wire-controlled unlocking assembly 40, through the design of the safety lock assembly 50, enables the safety lock assembly 50 to effectively restrict the sliding lever 44 from being actuated by the stop lever 51 when the safety lock assembly 50 is not released, thereby achieving the purpose of dual protection, greatly improving the safety of use, and effectively enhancing its practicality.

Claims

1. A trailer head unlocking device, applied between a trailer head and a wheelchair, wherein the trailer head has a docking seat, a hook rod is inserted through the docking seat, and the two ends of the hook rod slightly protrude from the side walls of the docking seat; the docking seat forms a snap-fit ​​groove; and the wheelchair has a coupling cover, the coupling cover has oblique snap-fit ​​grooves corresponding to the two ends of the hook rod; the coupling cover has a locking rod corresponding to the snap-fit ​​groove, for selectively locking or unlocking the coupling cover relative to the docking seat using an unlocking device; wherein the unlocking device is composed of a wire-controlled unlocking assembly, the wire-controlled unlocking assembly having: a fixed frame, a sliding pull rod, and a locking pry bar; characterized in that: The fixed frame has two sides that can be fixed to the docking seat. A pull cable passes through the fixed frame and can be pulled by a rocker arm. The sliding pull rod is slidably disposed in the docking seat. The sliding pull rod can be actuated by the pull cable between a lower locking position and an upper unlocking position. An elastic storage element is provided between the sliding pull rod and the docking seat, so that the sliding pull rod can generate an elastic preload to automatically return to the lower locking position. The locking rocker is pivotally mounted in the docking seat at a fulcrum. The sliding pull rod is linked to the locking rocker through at least one pivotally mounted connecting rod assembly. The connecting rod assembly has an elongated elliptical groove at one end corresponding to the locking rocker, for a pivot rod to pass through the groove. The long elliptical groove of the rod assembly and the top of the locking lever allow the pivot of the locking lever to partially slide within the long elliptical groove. The locking lever has an L-shaped structure and a hook portion that moves into the locking groove. The locking lever can rotate around the fulcrum, allowing the hook portion to selectively hook the locking lever embedded in the locking groove. The locking lever has at least one rotational torque spring, which generates a restoring force to automatically engage the locking lever. By operating the rocker arm to pull the cable, the sliding lever is moved to the upper unlock position, thereby actuating the linkage assembly to release the locking lever of the locking lever by the hook portion of the locking lever.

2. The trailer head unlocking device as described in claim 1, characterized in that: The wheelchair has a connecting rod, a coupling cover is formed at the front end of the connecting rod, and each side of the coupling cover has a corresponding side abutment. The oblique buckle groove is formed on the side abutments on both sides of the coupling cover. The locking rod spans the side abutments on both sides of the coupling cover. The trailer head is composed of a vehicle body upright. A handlebar is horizontally provided at the top of the vehicle body upright and a wheel is provided at the bottom. The docking seat is provided on a docking bushing pivotally provided on the vehicle body upright, and the line rocker is provided at one end of the handlebar.

3. The trailer head unlocking device as described in claim 1, characterized in that: The docking seat has an internal mounting channel that runs vertically through the buckle groove on one side of the wheelchair, allowing the locking lever to be pivotally mounted in the mounting channel using a pivot shaft. The docking seat also has a sliding channel that runs vertically through the mounting channel and is approximately parallel to it. The sliding rod slides in the sliding channel, and the lower section of the sliding channel is connected to the mounting channel via a connecting channel. The connecting rod assembly is located in the connecting channel.

4. The trailer head unlocking device as described in claim 1, characterized in that: The docking seat has at least one locking groove on each of its two side walls, and the fixing frame can be fixed to the locking groove by at least one fastener on each side.

5. The trailer head unlocking device as described in claim 1, characterized in that: The sliding rod has an accommodating groove, and the top of the accommodating groove has a half-shaft groove that is interconnected with the sliding rod. A limiting shaft is used to pass through the half-shaft groove of the sliding rod from the docking seat. The elastic storage member is located between the bottom end of the accommodating groove of the sliding rod and the limiting shaft of the docking seat, so that the sliding rod slides downward and is restricted to the lower locking position.

6. The trailer head unlocking device as described in claim 3, characterized in that: The locking lever has a pivot hole, through which the locking lever is pivoted onto the mating seat using the pivot shaft, serving as the fulcrum for the rotation of the locking lever.

7. The trailer head unlocking device as described in claim 1, characterized in that: The fixed frame of the wire-controlled unlocking assembly has a frame plate in front, the frame plate is provided with a safety lock assembly, and the safety lock assembly has a stop bar that slides through the frame plate, and the stop bar can slide between a stop position and a release position relative to the top edge of the sliding rod, so as to selectively restrict the sliding rod from being pulled upward.

8. The trailer head unlocking device as described in claim 7, characterized in that: The stop lever has a compression spring and a slide cylinder sequentially inserted at one end of the outer side of the frame plate and is locked to a knob. The slide cylinder and the knob respectively form a first cam portion and a second cam portion on their respective surfaces, so that the knob can move between a close position and a disengaged position relative to the slide cylinder, and the knob can move the stop lever to slide between the stop position and the release position relative to the top edge of the sliding rod.

9. The trailer head unlocking device as described in claim 8, characterized in that: The first and second cam sections can be relatively fitted inclined surfaces.

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