A worm gear operated ladder climbing device

Abstract

The application discloses a worm wheel and worm rod controlled ladder climbing device, and belongs to the technical field of railway wagon ladder climbing. The device comprises a ladder climbing mounting seat fixed to a wagon frame, a ladder climbing steel frame rotatably arranged on the ladder climbing mounting seat, and a worm wheel and worm rod driving device arranged on the back of the ladder climbing steel frame. The worm wheel and worm rod driving device comprises a driving device seat, an operating hand wheel, a lead screw and a lifting nut. The driving device seat is hingedly connected to the ladder climbing mounting seat. The operating hand wheel drives the lead screw to rotate by a worm wheel and worm rod pair. The lifting nut is threadedly connected to the lead screw and fixedly connected to the ladder climbing steel frame. The ladder climbing steel frame can be turned over by rotating the hand wheel, so that the ladder climbing steel frame can be unfolded and folded. The device is further integrated with a spring buffering device, a segmented hinged self-adapting structure and an adjustable binding and reinforcing device. The application adopts a pure mechanical transmission structure, does not need to be provided with a power supply and a hydraulic system, is simple and reliable in structure, and is labor-saving in operation. The device has the functions of buffering and damping, road self-adapting, storage fixing and the like.

Description

Technical Field

[0001] This invention relates to the field of railway freight car ladder technology, specifically to a ladder device controlled by a worm gear. Background Technology

[0002] Existing railway freight cars lack end ramps, requiring wheeled and tracked vehicles to be hoisted or accessed via platforms of equal height to reach the loading deck, placing high demands on loading and unloading areas. While existing truck ramps typically employ hydraulic control, using the extension and retraction of hydraulic cylinders to rotate the ramp, this solution is labor-saving but requires a hydraulic power unit, electromagnetic control valves, and an onboard power supply system, resulting in a complex overall system with high manufacturing and maintenance costs. Furthermore, hydraulic sealing elements are poorly adapted to the dusty and temperature-sensitive environments of freight transport, prone to media leakage and valve jamming. Additionally, its operation is highly dependent on the onboard power supply; if the electrical or hydraulic system fails, the ramp cannot complete its extension and retraction, resulting in insufficient emergency response capabilities. Summary of the Invention

[0003] The purpose of this invention is to address the shortcomings of existing technologies by providing a worm gear-controlled ladder climbing device. The ladder climbing device of this invention is driven and controlled by a worm gear, eliminating the need for solenoid valves and power supplies. It has a simple structure, is a mature purely mechanical mechanism, and is low in cost and highly reliable.

[0004] To solve the above-mentioned technical problems, the present invention provides a worm gear controlled ladder device, including a ladder mounting base, a ladder steel frame rotatably mounted on the ladder mounting base, and a worm gear drive device mounted on the back of the ladder steel frame. The worm gear drive device includes a drive device seat, an operating handwheel, a lead screw, and a lifting nut. The drive device seat is rotatably mounted on the ladder mounting base. One end of the operating handwheel and the lead screw are both located in the drive device seat and rotatably connected to the drive device seat. The operating handwheel is used to drive the lead screw to rotate. The lifting nut is sleeved on the lead screw and threadedly engaged with the lead screw. The lifting nut is fixedly connected to the ladder steel frame.

[0005] In some embodiments, a drive shaft is provided on the operating handwheel, the drive shaft is a worm gear, and a worm wheel is fixedly provided on the lead screw, and the drive shaft and the worm wheel mesh and transmit power.

[0006] In some embodiments, a buffer device is provided on the back of the ladder frame to reduce impact when the ladder frame is deployed and to provide assistance when the ladder frame is retracted.

[0007] In some embodiments, the buffer device includes an upper mounting base and a lower mounting base. One end of the upper mounting base is rotatably connected to a ladder mounting base, and the other end of the upper mounting base is fixedly connected to a connecting rod. A spring is sleeved on the connecting rod, and one end of the connecting rod is slidably engaged with the lower mounting base and provided with a limiting ring. The two ends of the spring abut against the upper mounting base and the lower mounting base, and the spring presses the lower mounting base onto the limiting ring. The lower mounting base is fixedly connected to the ladder steel frame.

[0008] In some embodiments, the ladder mounting base is provided with a ladder steel frame pivot and a buffer device pivot, which are arranged in parallel and staggered order, so that the spring is compressed when the ladder steel frame is unfolded.

[0009] In some embodiments, a binding and reinforcement device is provided on the front of the ladder steel frame. The binding and reinforcement device includes a chain and an adjustment device. One end of the chain is connected to the adjustment device, which is used to adjust the total length of the binding and reinforcement device. Both ends of the binding and reinforcement device are detachably connected to the ladder steel frame and the truck frame, respectively, for fixing the ladder steel frame to the truck frame after the ladder steel frame is retracted.

[0010] In some embodiments, the ladder mounting base is provided with an upper buffer block and a lower buffer block, which are used to prevent the ladder steel frame from colliding directly with the ladder mounting base when the ladder steel frame is retracted or extended.

[0011] In some embodiments, the ladder steel frame includes an upper ladder steel frame and a lower ladder steel frame connected in sequence. The upper ladder steel frame and the lower ladder steel frame are rotatably connected. A limiting device is provided at the connection between the upper ladder steel frame and the lower ladder steel frame. The limiting device is used to limit the relative rotation angle between the upper ladder steel frame and the lower ladder steel frame.

[0012] In some embodiments, a connecting shaft is provided at one end of the upper steel frame of the ladder near the lower steel frame of the ladder, and a rotating seat is provided at one end of the lower steel frame of the ladder near the upper steel frame of the ladder. The connecting shaft is rotatably connected to the rotating seat. A limiting device is provided on the outside of the rotating seat. The limiting device includes two blocks and a slider. An outer edge is provided on the outside of the rotating seat. The two blocks are fixed on the outer edge. The slider is fixed on the connecting shaft. The slider is located between the two blocks, so that the slider can only move between the two blocks.

[0013] In some embodiments, a support base is provided at the bottom of the ladder frame, which is used to support the ladder frame on the ground after it is unfolded.

[0014] The beneficial effects of this invention are as follows: 1. This invention adopts a purely mechanical drive structure with worm gear and lead screw, which eliminates the need for hydraulic solenoid valves, power units and vehicle power supplies, greatly reducing manufacturing costs and failure rates. The mechanism is mature and stable. At the same time, the operating handwheels are located on both sides of the vehicle, allowing operators to complete the ladder raising and lowering from the ground without having to climb to a height, making it convenient and safe to use.

[0015] 2. The present invention is equipped with a spring-type buffer device. When the ladder is unfolded and lands, the spring is compressed, which can absorb the impact energy of the landing and avoid damage to the rigid structure from collision. During the process of the ladder being retracted, the spring rebounds and releases energy, offsetting part of the ladder's own weight and significantly reducing the labor intensity of handwheel operation.

[0016] 3. The ladder steel frame of the present invention adopts a split structure with two sections hinged together. A limiting device is provided at the connection point, which allows the lower section of the ladder to deflect relatively within a range of ±5°. With the bottom support seat, it can automatically adjust the fitting angle on uneven ground to ensure stable support and improve the safety of boarding.

[0017] 4. The present invention is equipped with an adjustable chain-type binding and reinforcement device, which can quickly lock and fix the ladder to the truck frame after it is retracted, so as to prevent the ladder from shaking and loosening during the journey. 5. Bushings are provided at each hinge shaft of the present invention to effectively reduce wear on rotating parts and extend the overall service life of the device. Attached Figure Description

[0018] Figure 1 This is an isometric view of the present invention; Figure 2 This is the front view of the present invention; Figure 3 This is a schematic diagram of the invention when unfolded; Figure 4 This is a schematic diagram of the structure of the ladder mounting base of the present invention; Figure 5 This is a schematic diagram of the buffer device of the present invention; Figure 6 This is a schematic diagram of the worm gear drive device of the present invention; Figure 7 This is a schematic diagram of the steel frame structure of the ladder of the present invention; Figure 8 This is a schematic diagram of the limiting device of the present invention; Figure 9 This is a schematic diagram of the binding and reinforcement device of the present invention.

[0019] Reference numerals: 11. Handwheel; 12. Buffer device; 13. Worm gear drive device; 14. Upper steel frame of ladder; 15. Lower steel frame of ladder; 16. Binding and reinforcement device; 17. Truck frame; 110. Ladder steel frame pivot; 111. Ladder mounting base; 112. Upper buffer block; 113. Buffer device pivot; 114. Spare pivot; 115. Drive device pivot; 116. Upper mounting base; 121. Spring; 122. Lower mounting base; 123. Lead screw; 131. Lifting nut; 132. Bushing; 141. Upper steel structure of ladder; 142. Anti-slip strip; 143. Connecting pivot; 144. Lower steel structure of ladder; 145. Support base; 146. Slider; 147. Rotating base; 151. Stop; 152. Shackle; 161. Chain; 162. Adjustment device; 163. Detailed Implementation

[0020] To make the technical problems to be solved, the technical solutions, and the beneficial effects of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0021] like Figure 2 , 3 As shown, the worm gear controlled ladder device of the present invention is installed at one end of the truck frame 17 for motor vehicles to get on and off the truck.

[0022] The device includes a ladder mounting base 111, a ladder steel frame, a worm gear drive device 13, a buffer device 12, and a binding and reinforcement device 16.

[0023] like Figure 4 As shown, the ladder mounting base 111 is fixedly connected to the truck frame 17. A ladder steel frame rotating shaft 110, a drive device rotating shaft 116, and a buffer device rotating shaft 114 are fixedly mounted on the ladder mounting base 111. The ladder steel frame rotating shaft 110 and the drive device rotating shaft 116 are arranged parallel and offset, while the drive device rotating shaft 116 and the buffer device rotating shaft 114 are arranged coaxially. The ladder steel frame is rotatably mounted on the ladder mounting base 111 via the ladder steel frame rotating shaft 110 and can rotate around the ladder steel frame rotating shaft 110 between the retracted and extended states. An upper buffer block 112 and a lower buffer block 113 are also fixedly mounted on the ladder mounting base 111. The upper buffer block 112 corresponds to the retracted limit position of the ladder steel frame, and the lower buffer block 113 corresponds to the extended limit position of the ladder steel frame. When the ladder steel frame rotates to its final position, it first makes flexible contact with the buffer blocks to prevent a direct rigid collision between the ladder steel frame and the ladder mounting base 111, thus protecting the structural components. A spare pivot 115 can also be installed on the ladder mounting base 111 to adapt to the installation requirements of different vehicle models or to expand functions.

[0024] like Figure 1As shown, the worm gear drive device 13 and the buffer device 12 are both located on the back of the ladder steel frame, and are used to drive the ladder steel frame to rotate and to buffer and dampen shocks, as well as to assist operation; Figure 2 As shown, the binding and securing device 16 is located on the front of the ladder frame and is used to lock and secure the ladder to the truck frame 17 after it is retracted. The back of the ladder frame is the side facing the ground when the ladder frame is unfolded.

[0025] like Figure 6 As shown, the worm gear drive device 13 includes a drive unit base, an operating handwheel 11, a lead screw 131, and a lifting nut 132. The drive unit base is rotatably mounted on the ladder mounting base 111 via the drive unit shaft 116, allowing the entire drive unit to adaptively adjust its angle as the ladder steel frame rotates, thus avoiding motion interference.

[0026] Both the operating handwheel 11 and one end of the lead screw 131 are rotatably mounted inside the drive unit base via bearings. The drive shaft of the operating handwheel 11 and the axis of the lead screw 131 are arranged spatially perpendicularly. The drive shaft of the operating handwheel 11 is a worm gear, and a worm wheel is installed at the end of the lead screw 131 located inside the drive unit base. The drive shaft and the worm wheel mesh and transmit power. When the operating handwheel 11 is rotated, the power is transmitted through the worm wheel, causing the lead screw 131 to rotate around its own axis.

[0027] The lifting nut 132 is sleeved on the lead screw 131, and the outer side of the lifting nut 132 is fixedly connected to the ladder steel frame. When the lead screw 131 rotates in the forward or reverse direction, the lifting nut 132 moves back and forth along the axial direction of the lead screw 131, thereby driving the ladder steel frame to rotate around the ladder steel frame pivot 110 through push and pull action, realizing the unfolding and retraction of the ladder.

[0028] Furthermore, the operating end of the handwheel 11 can be extended to both sides of the vehicle, allowing operators to operate it from either side of the vehicle without having to climb it, thus improving ease of use and safety.

[0029] like Figure 5 As shown, the buffer device 12 includes an upper mounting base 121, a connecting rod, a spring 122, and a lower mounting base 123. One end of the upper mounting base 121 is rotatably connected to the ladder mounting base 111 via the buffer device pivot 114, and the other end of the upper mounting base 121 is fixedly connected to one end of the connecting rod. The other end of the connecting rod is inserted into the inner cavity of the lower mounting base 123, forming a sliding fit with the lower mounting base 123. A limit ring is provided at the lower end of the connecting rod to limit the downward stroke of the lower mounting base 123 and prevent it from falling off the connecting rod.

[0030] Spring 122 is sleeved on the connecting rod, with its upper end abutting against the lower end face of the upper mounting base 121 and its lower end abutting against the upper end face of the lower mounting base 123. In the free state, the elastic force of spring 122 presses the lower mounting base 123 tightly against the limiting ring of the connecting rod. A smooth round rod is fixedly installed at the end of the lower mounting base 123 away from spring 122, and the lower mounting base 123 is fixedly connected to the climbing ladder steel frame through the smooth round rod, moving synchronously with the climbing ladder steel frame.

[0031] Combination Figure 4 As shown, the ladder frame pivot 110 and the buffer device pivot 114 are parallel and staggered, and their axes do not coincide. When the ladder frame unfolds and flips downwards, the lower mounting base 123 rotates synchronously with the ladder frame and slides upwards relative to the upper mounting base 121, compressing the spring 122 to store energy, thereby absorbing the impact energy during the ladder unfolding process and reducing the impact of landing. When the ladder frame retracts and flips upwards, the spring 122 gradually rebounds and releases energy, pushing the lower mounting base 123 upwards to offset part of the ladder's own weight and reduce the force required for the operator to turn the handwheel.

[0032] like Figure 7 As shown, the ladder steel frame is a segmented structure, including an upper ladder steel frame 14 and a lower ladder steel frame 15 connected in sequence. The two are hinged at the ends, and a limit device is provided at the hinge to limit the relative rotation angle and realize adaptive adjustment on uneven surfaces.

[0033] Specifically, the upper steel frame 14 of the ladder includes an upper steel structure 142, on the front of which multiple anti-slip strips 143 are spaced apart to increase friction. A transverse connecting pivot 144 is provided at the lower end of the upper steel frame 14.

[0034] The lower steel frame 15 of the ladder includes a lower steel structure 145. A rotating seat 151 is provided at the upper end of the lower steel structure 145. A connecting shaft 144 passes through the rotating seat 151, and the two are rotatably connected to achieve a relative hinge between the upper steel frame 14 and the lower steel frame 15. A bushing 141 is provided between the mating surfaces of the connecting shaft 144 and the rotating seat 151 to reduce rotational wear and improve the service life of the hinged parts.

[0035] like Figure 8As shown, a limiting device is disposed on the outer end face of the rotating seat 151, including two stops 152 and a slider 147. The outer end face of the rotating seat 151 is provided with an arc-shaped outer edge, and the two stops 152 are fixedly fixed on the outer edge at circumferential intervals; the slider 147 is fixedly connected to the end of the connecting rotating shaft 144, rotates synchronously with the connecting rotating shaft 144, and the slider 147 is located between the two stops 152. The two stops 152 limit the rotation stroke of the slider 147, so that the lower steel frame 15 of the ladder can only deflect relative to the upper steel frame 14 of the ladder within a preset angle range. In this embodiment, the preset deflection angle is ±5°, which meets the adaptive fitting requirements of uneven road surfaces.

[0036] A support base 146 is fixedly installed at the bottom of the lower steel frame 15 of the ladder. After the ladder is unfolded, the support base 146 directly contacts the ground, which improves the stability of the support.

[0037] like Figure 9 As shown, the binding and reinforcement device 16 includes a shackle 161, a chain 162, and an adjustment device 163. One end of the chain 162 is detachably connected to the center of the front of the ladder steel frame via the shackle 161, and the other end of the chain 162 is connected to the adjustment device 163. The adjustment device 163 is used to adjust the total working length of the binding and reinforcement device 16, and the adjustment device 163 uses a turnbuckle.

[0038] When the ladder frame is retracted to the position close to the truck frame 17, the free end of the binding and reinforcement device 16 is connected to the preset fixing point on the truck frame 17 through the shackle. The adjustment device 163 is operated to tighten the chain 162, which can securely lock the ladder frame in the storage position, prevent the ladder from shaking or loosening during vehicle operation, and improve driving safety.

[0039] The specific working process of this device is as follows: When the ladder needs to be deployed, the operator stands on the ground to the side of the vehicle and turns the operating handwheel 11. The power is transmitted through the worm gear, which drives the lead screw 131 to rotate in the forward direction. The lifting nut 132 moves away from the lead screw 131, pushing the ladder frame to rotate downwards around the ladder frame pivot 110. During the rotation, the lower mounting base 123 of the buffer device 12 moves synchronously with the ladder frame, gradually compressing the spring 122 to absorb the rotation energy and reduce the impact of landing. When the ladder frame is rotated to the deployed position, the bottom support base 146 contacts the ground. If the ground is uneven, the lower steel frame 15 of the ladder can adaptively deflect within ±5° around the connecting pivot 144 to make the support base 146 as close to the ground as possible, ensuring stable support.

[0040] When the ladder needs to be retracted, the operating handwheel 11 is turned in the opposite direction, causing the lead screw 131 to rotate in the opposite direction. This moves the lifting nut 132 along the direction close to the lead screw 131, pulling the ladder frame upward around the ladder frame pivot 110. During the retraction process, the compressed spring 122 inside the buffer device 12 gradually rebounds, pushing the lower mounting base 123 upward, providing auxiliary power for the ladder to retract, offsetting part of the ladder's weight, and reducing the operating force. When the ladder frame is flipped to the retracted position, the ladder frame is tightened and fixed to the truck frame 17 by the binding and reinforcement device 16, completing the storage.

[0041] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included within the protection scope of the present invention.

Claims

1. A worm gear controlled ladder climbing device, characterized in that, The system includes a ladder mounting base (111), on which a ladder steel frame is rotatably mounted. A worm gear drive device (13) is provided on the back of the ladder steel frame. The worm gear drive device (13) includes a drive device base, an operating handwheel (11), a lead screw (131), and a lifting nut (132). The drive device base is rotatably mounted on the ladder mounting base (111). One end of the operating handwheel (11) and the lead screw (131) are both located in the drive device base and rotatably connected to the drive device base. The operating handwheel (11) is used to drive the lead screw (131) to rotate. The lifting nut (132) is sleeved on the lead screw (131) and threadedly engaged with the lead screw (131). The lifting nut (132) is fixedly connected to the ladder steel frame.

2. The worm gear controlled ladder climbing device according to claim 1, characterized in that, The operating handwheel (11) is provided with a drive shaft, which is a worm gear. The lead screw (131) is fixedly provided with a worm wheel, and the drive shaft and the worm wheel mesh and transmit power together.

3. The worm gear controlled ladder climbing device according to claim 1, characterized in that, A buffer device (12) is provided on the back of the climbing steel frame. The buffer device (12) is used to reduce the impact when the climbing steel frame is deployed on the ground and to provide assistance when the climbing steel frame is retracted.

4. The worm gear controlled ladder climbing device according to claim 3, characterized in that, The buffer device (12) includes an upper mounting base (121) and a lower mounting base (123). One end of the upper mounting base (121) is rotatably connected to the ladder mounting base (111). The other end of the upper mounting base (121) is fixedly connected to a connecting rod. A spring (122) is sleeved on the connecting rod. One end of the connecting rod is slidably engaged with the lower mounting base (123) and a limiting ring is provided. The two ends of the spring (122) abut against the upper mounting base (121) and the lower mounting base (123). The spring (122) presses the lower mounting base (123) onto the limiting ring. The lower mounting base (123) is fixedly connected to the ladder steel frame.

5. The worm gear controlled ladder climbing device according to claim 4, characterized in that, The ladder mounting base (111) is provided with a ladder steel frame pivot (110) and a buffer device pivot (114). The ladder steel frame pivot (110) and the buffer device pivot (114) are arranged in parallel and staggered order, so that the spring (122) is compressed when the ladder steel frame is unfolded.

6. The worm gear controlled ladder climbing device according to any one of claims 1 to 5, characterized in that, The front of the ladder steel frame is provided with a binding and reinforcement device (16). The binding and reinforcement device (16) includes a chain (162) and an adjustment device (163). One end of the chain (162) is connected to the adjustment device (163). The adjustment device (163) is used to adjust the total length of the binding and reinforcement device (16). The two ends of the binding and reinforcement device (16) are detachably connected to the ladder steel frame and the truck frame (17) respectively, and are used to fix the ladder steel frame to the truck frame (17) after the ladder steel frame is retracted.

7. The worm gear controlled ladder climbing device according to any one of claims 1 to 5, characterized in that, The ladder mounting base (111) is provided with an upper buffer block (112) and a lower buffer block (113). The upper buffer block (112) and the lower buffer block (113) are used to prevent the ladder steel frame from colliding directly with the ladder mounting base (111) when the ladder steel frame is retracted or extended.

8. The worm gear controlled ladder climbing device according to any one of claims 1 to 5, characterized in that, The ladder steel frame includes an upper ladder steel frame (14) and a lower ladder steel frame (15) connected in sequence. The upper ladder steel frame (14) and the lower ladder steel frame (15) are rotatably connected. A limiting device is provided at the connection between the upper ladder steel frame (14) and the lower ladder steel frame (15). The limiting device is used to limit the relative rotation angle between the upper ladder steel frame (14) and the lower ladder steel frame (15).

9. The worm gear controlled ladder device according to claim 8, characterized in that, A connecting shaft (144) is provided at one end of the upper steel frame (14) of the ladder near the lower steel frame (15). A rotating seat (151) is provided at one end of the lower steel frame (15) of the ladder near the upper steel frame (14). The connecting shaft (144) is rotatably connected to the rotating seat (151). The limiting device is provided on the outside of the rotating seat (151). The limiting device includes two blocks (152) and a slider (147). An outer edge is provided on the outside of the rotating seat (151). The two blocks (152) are fixed on the outer edge. The slider (147) is fixed on the connecting shaft (144). The slider (147) is located between the two blocks (152), so that the slider (147) can only move between the two blocks (152).

10. The worm gear controlled ladder climbing device according to claim 8, characterized in that, The bottom of the climbing ladder steel frame is provided with a support base (146), which is used to support the climbing ladder steel frame on the ground after it is unfolded.

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