Folding step ladder for rail transit

Abstract

A folding step ladder for rail transit, comprising a step ladder (5) and a connecting frame (3) used for mounting the step ladder (5). A telescopic arm (301) used for driving the step ladder (5) to move left and right is slidably connected to the lower portion of the connecting frame (3), and first driving devices (7) used for driving the step ladder (5) to rotate are hinged to the two sides of the telescopic arm (301); and the rear end of the connecting frame (3) is provided with a step lock (4) used for fixing the folding step ladder in a folded state. When the folding step ladder is in use, the whole folding step ladder is in a suspension state and is not limited by the height of a station platform (8). When the folding step ladder is not in use, the folding step ladder is driven by the telescopic arm (301) to retract to the bottom of a train, the bottom of the folding step ladder in the folded state is connected to the step lock (4), and both ends of the folding step ladder have force bearing points, thereby ensuring the stability of a retraction state.

Description

Folding step ladder for rail transit Technical Field

[0001] The invention relates to a rail transit vehicle body accessory, in particular to a telescopic folding step ladder for rail transit. Background Art

[0002] In rail transit train door systems, when an emergency vehicle situation occurs and passengers need to evacuate, emergency evacuation only through the front or rear doors of the train poses the risk of delayed evacuation. A folding step ladder is an effective auxiliary device for passengers getting off or on the train through the passenger compartment doors. Patent application publication number CN 112356862 A discloses a retractable emergency evacuation ladder suitable for high-speed maglev trains. The folding step ladder consists of a hinged pair of multiple connecting rods and a pedal. During use, a first support rod rotatably connected to a storage compartment rotates to extend the folding step ladder, while a second support rod extends the folding step ladder. The folding step ladder then retracts back into the storage compartment. After evacuation, the folding step ladder is located above the rotating shaft of the first and second support rods. This device helps ensure the stability of the folding step ladder after evacuation. However, since the folding step ladder needs to withstand ballast during use, the first and second support rods also bear ballast. The second support rod can easily become overloaded, making it impossible to effectively retract the folding step ladder. The invention patent application with publication number CN 115337567 A discloses a stepped emergency evacuation device, in which a folding step ladder is also composed of a hinged pair and pedals cross-hinged by multiple connecting rods. The folding step ladder is controlled to extend from the bottom of the vehicle body by a V-shaped support plate rotatably mounted to the bottom of the vehicle body, and the extension of the folding step ladder is controlled by a pedal deployment rod and a gas spring rotatably connected to the support plate. This scheme takes into account the situation when the folding step ladder is in use. When the folding step ladder is in a retracted state, the folding step ladder is located as a whole below the gas spring and the support plate, and is suspended. The folding step ladder is stabilized only by the support plate and the gas spring, and the stability of the retracted state is low. Patent application CN 116101177 A discloses a vehicle-mounted, fully automatic, retractable folding ladder. The folding ladder features a parallelogram-shaped frame that slides out along a linear motion module and then rotates around one end of the module to function as a step ladder. When retracted, it is stored within the module. Both sides of the device are connected to the module, and its power unit and the module are aligned. The power transmission is driven by multiple bevel gears, resulting in a complex transmission and a large space requirement. All of these step ladders require a platform for use. Summary of the Invention

[0003] Purpose of the invention: The purpose of the present invention is to provide a foldable step ladder for rail transit that is easy to unfold and fold.

[0004] Technical solution: The folding step ladder for rail transit described in the present invention includes a step ladder and a connecting frame for installing the step ladder. A telescopic arm for driving the step ladder to move back and forth is slidably connected to the bottom of the connecting frame, and a first drive device for driving the step ladder to rotate is hinged on both sides of the telescopic arm; the rear end of the connecting frame is provided with a pedal lock for fixing the folding step ladder in a folded state.

[0005] The step ladder is a parallelogram-shaped folding step ladder. When the folding step ladder of the present invention is in use, the step ladder as a whole is in a suspended state and is not restricted by the platform height. When the step ladder is not in use, it is retracted to the bottom of the train by the telescopic arm. The bottom of the step ladder in the closed state is locked and connected to the pedal. There are force points at both ends of the step ladder to ensure the stability of the retracted state.

[0006] Preferably, the step ladder is connected to a retractable step at the bottom, which is slidably connected to both sides of the step ladder. Adding a retractable step at the bottom of the step ladder can adapt to the limited width of the train floor, while also extending the overall length of the step ladder and shortening the distance between the step and the platform. When not in use, the retractable step is retracted and secured by a step lock, ensuring stability when the step ladder is retracted.

[0007] Preferably, the width of the step ladder is not less than the width of the connecting frame. The step ladder can be retracted or extended for use by rotating along the telescopic arm, and the step ladder is not limited by the size of the telescopic arm, thereby ensuring the space utilization of the step ladder.

[0008] Preferably, in order to ensure the safety of the user, the first drive device is hinged to the rear of the step ladder, and foldable handrails are hinged on both sides of the front of the step ladder. The foldable handrails can also be integrated into the telescopic ladder, and when in use, it can be directly straightened.

[0009] Preferably, the folding handrail includes a handrail rod extending parallel to both sides of the extended step ladder, and a support rod for supporting the handrail rod, the bottom of the support rod being hingedly connected to the step ladder. More preferably, the support rod is a retractable telescopic rod. The use of a telescopic rod allows the height of the folding handrail to be adjusted.

[0010] Preferably, the first driving device is hinged to the rear of the second step of the step ladder at one end close to the step ladder, thereby shortening the longitudinal and transverse distances between the step surface of the vehicle body and the first step of the step ladder to ensure stability and safety.

[0011] Preferably, to increase the connection strength between the step ladder and the telescopic tread, and to ensure that the telescopic tread can slide along both sides of the step ladder, the telescopic tread and the step ladder are slidably connected via a sliding shaft and a sliding groove. Forward-extending limit pins are provided at the top of each side of the telescopic tread, and outwardly extending limit blocks are provided at the bottom of each side of the step ladder for engaging the limit pins. More preferably, a sliding shaft and a sliding groove are provided on each side of the step ladder and the telescopic tread, respectively, i.e., the sliding shafts and sliding grooves on the two sides of the step ladder and the telescopic tread are asymmetrically arranged.

[0012] Preferably, in order to reduce the space occupied by the power device, the telescopic arm and the connecting frame are slidably connected by a slider and a guide rail, and a second driving device is provided between the connecting frame and the telescopic arm to push the telescopic arm to extend. The first driving device and the second driving device are both gas springs. Compared with other power devices, gas springs are smaller in size and are not affected by power outages.

[0013] Preferably, a connecting rope is connected to the bottom of the step ladder for unlocking the step lock and assisting in pulling out the step ladder. When the unlocking element of the step lock fails to work, the connecting rope drives the unlocking cable drum of the step lock to rotate, causing the mechanical lock stop to rotate counterclockwise, overcoming the torsion spring torque. This releases the locking limit between the mechanical lock hook flange and the mechanical lock stop, allowing the mechanical lock hook to rotate smoothly, completing the unlocking process.

[0014] Beneficial effects: Compared with the existing technology, the present invention has the following significant advantages: 1. Low requirements for the platform during use and high stability during recycling; 2. High space utilization rate; 3. Guaranteed safety during use. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] FIG1 is a side view of the foldable step ladder of the present invention in use.

[0016] FIG2 is a schematic diagram of the folding step ladder of the present invention in use from a first viewing angle.

[0017] FIG3 is a schematic diagram of the folding step ladder of the present invention in use from a second viewing angle.

[0018] FIG4 is a schematic structural diagram of the folding step ladder of the present invention.

[0019] FIG5 is a schematic diagram of the folding step ladder of the present invention in a retracted state. DETAILED DESCRIPTION

[0020] The technical solution of the present invention will be further described below with reference to the accompanying drawings.

[0021] As shown in Figures 1 to 5, the telescopic folding step ladder for emergency escape on a railway train according to the present invention primarily comprises a step ladder 5 and a connecting frame 3. The connecting frame 3 is mounted on the bottom of the train and connected to the bottom of the train body via bolts. A telescopic arm 301 is slidably mounted on the bottom of the connecting frame 3, extending from the bottom of the train. The telescopic arm 301 is used to propel the step ladder 5 out as a whole. Both sides of the telescopic arm 301 are hingedly connected to a first drive device 7 that rotates the bottom of the step ladder 5 until the step ladder 5 is ready for use. A pedal lock 4 is mounted at the rear end of the connecting frame 3, locking the step ladder 5. A switch 401 is mounted on the skirt of the train body, unlocking the step ladder. A steel rope is connected to the bottom of the step ladder 5 to unlock the pedal lock 4 and assist in pulling the step ladder 5 out. The pedal lock is conventional and will not be described in detail here.

[0022] The telescopic arm 301 can be installed at the bottom of the connecting frame 3 through a linear slide rail. The second drive device 6 is installed between the telescopic arm 301 and the connecting frame 3. The first drive device and the second drive device are gas springs to avoid the impact of power failure.

[0023] The step ladder 5 is a parallelogram-shaped folding step ladder with four steps in total, wherein the fourth step is a telescopic step 501, and the two sides of the fourth step are slidingly connected to the two sides of the step ladder 5. The two sides of the rear of the second step of the step ladder 5 are hinged to the front end of the telescopic arm 301. When not in use, the fourth step is retracted and overlaps with the third step.

[0024] Folding handrails are hinged on both sides of the front of the step ladder 5. The folding handrail 2 includes a support rod 21 and a handrail rod 22 at a certain angle to the support rod. The support rod 21 is a pull-out telescopic rod that can adjust the height of the folding handrail. The bottom of the support rod 21 is hinged to the front side of the folding pedal assembly 5. When the support rod is upright, the handrail rod 22 is parallel to the main frames on both sides of the step ladder 5 in use.

[0025] The width of the step ladder 5 and the telescopic arm 301 (the length direction of the pedal in the figure is the width of the step ladder) are not less than the width of the connecting frame 3.

[0026] The telescopic step 501 and the step ladder 5 are respectively provided with a sliding shaft 502 and a sliding groove 503 on both sides, and the telescopic step 501 and the step ladder are slidably connected by the sliding shaft and the sliding groove. The top of each side of the telescopic step 501 is provided with a forward-extending limit pin 504, and the bottom of each side of the step ladder is provided with a limit block 505 extending outward to overlap the limit pin.

[0027] When the folding step ladder is unfolded for use, the pedal lock 401 is unlocked manually. The pedal lock 4 can be unlocked with the help of a wire rope, and the step ladder 5 is pulled at the same time. The step ladder 5 is pushed out by the first gas spring 7 and the telescopic arm 301, and then pushed to the downward-inclined suspended use state by the second gas spring 6 (the pushing out and rotating states can also be performed simultaneously, in no particular order). The pedals of the step ladder 5 are manually flipped downward to the unfolded state, the vehicle body 1 and the platform 8 are connected, and the folding handrails 202 on both sides are rotated and straightened. It is determined whether to pull out the fourth step pedal 501 as needed, and it can be used; when retracting, the fourth step pedal is manually pushed back, and the pedals of the step ladder 5 are flipped upward to the folded state. The step ladder 5 retracts and collides with the pedal lock 4, and then the pedals are automatically locked.

Claims

1. A folding step ladder for rail transit, comprising a step ladder (5) and a connecting frame (3) for mounting the step ladder, characterized in that: A telescopic arm (301) is slidably connected below the connecting frame for driving the step ladder to move back and forth, and a first driving device (7) is hinged on both sides of the telescopic arm for driving the step ladder to rotate; a pedal lock (4) is provided at the rear end of the connecting frame for fixing the foldable step ladder in a folded state.

2. The folding step ladder for rail transit according to claim 1, characterized in that: A telescopic pedal (501) is connected to the bottom of the foldable step ladder, and the telescopic pedal is slidably connected to both sides of the step ladder.

3. The folding step ladder for rail transit according to claim 1, characterized in that: The width of the step ladder is not less than the width of the connecting frame.

4. The folding step ladder for rail transit according to claim 1, characterized in that: The first driving device is hinged to the rear of the step ladder, and folding handrails (2) are hinged to the front sides of the step ladder respectively.

5. The folding step ladder for rail transit according to claim 4, characterized in that: The folding handrail comprises a support rod (201) and handrail rods (202) parallel to both sides of the step ladder in the unfolded state; the support rod is a pull-out telescopic rod, and the bottom of the support rod is hinged to the step ladder.

6. The folding step ladder for rail transit according to claim 1, characterized in that: The first driving device is hinged to the rear of the second step of the step ladder.

7. The folding step ladder for rail transit according to claim 2, characterized in that: The telescopic pedal and the two sides of the step ladder are slidably connected via a sliding shaft (502) and a sliding groove (503); the tops of the two sides of the telescopic pedal are provided with forward-extending limit pins (504); the bottoms of the two sides of the step ladder are provided with limit blocks (505) extending outwards and used for overlapping the limit pins.

8. The folding step ladder for rail transit according to claim 7, characterized in that: The sliding shafts and sliding grooves on both sides of the step ladder and the telescopic pedal are arranged asymmetrically.

9. The folding step ladder for rail transit according to claim 1, characterized in that: The telescopic arm is slidably connected to the connecting frame via a slider and a guide rail, and a second driving device (6) for pushing the telescopic arm to extend is provided between the connecting frame and the telescopic arm, and both the first driving device and the second driving device are gas springs.

10. The folding step ladder for rail transit according to claim 1, characterized in that: A connecting rope for unlocking a pedal lock and assisting in pulling out the folding pedal is connected to the bottom of the step ladder.

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