Elevator pit ladder

Abstract

The invention relates to an elevator pit ladder which comprises at least one fixing support arranged on a wall body of an elevator shaft; one end of the supporting arm is connected to the fixing support, and the supporting length of the supporting arm can be changed; the ladder main body is connected to the other end of the supporting arm; and the control assembly is connected to the supporting arm and can control the supporting length of the supporting arm, so that the distance between the ladder main body and the wall body is changed between the farthest distance and the closest distance. According to the elevator pit ladder, small pit space can be occupied, the situation that a worker stretches arms or tools into a pit to unfold the ladder body is avoided, and use convenience is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of elevator equipment, and in particular to an elevator pit ladder. Background Art

[0002] With the rapid advancement of urbanization, high-rise buildings have gradually become the symbol of the city, and the demand for elevators is also growing rapidly. Usually, the elevator pit is equipped with elevator counterweight guardrails, elevator buffer bases, drainage devices and other equipment. In order to facilitate the daily inspection and maintenance of these equipment, a ladder for workers to enter and exit the pit needs to be installed in the pit.

[0003] According to the requirements of the Safety Specification for Elevator Manufacturing and Installation (GB / T7588.1-2020), a gap of no less than 200mm must be left between the back of the ladder installed in the elevator pit and the hoistway wall, and the distance from the floor door of the elevator hoistway shall not exceed 800mm. However, due to the limited pit space, the existing fixed ladder installed in the predetermined position in the pit will occupy a large pit space, thereby reducing the utilization rate of the pit space.

[0004] In order to solve the above problems, the ladder can be designed to be a retractable or foldable structure. However, the existing retractable or foldable ladder structure still requires workers to use their arms or tools to reach into the pit to unfold the ladder, which is less convenient.

[0005] The information disclosed in this background section is only intended to enhance understanding of the overall background of the invention and should not be taken as an acknowledgement or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art. Summary of the invention

[0006] In view of the defects existing in the prior art, an object of the present invention is to provide an elevator pit ladder, which can occupy a smaller pit space and has better convenience in use.

[0007] The present invention provides an elevator pit ladder, comprising: at least one fixed bracket, which is arranged on the wall of the elevator shaft; at least one group of support arms, one end of which is connected to the fixed bracket and can change the support length; a ladder body, which is connected to the other end of the support arm; and a control component, which is connected to the support arm and can control the support length of the support arm so that the distance between the ladder body and the wall changes between the farthest distance and the closest distance.

[0008] According to an exemplary embodiment of the present invention, each of the at least one group of support arms comprises: a first arm, both ends of which are hinged to the fixed bracket and the ladder body, respectively; and a second arm, a middle portion of which is hinged to the middle portion of the first arm, an end of the second arm close to the fixed bracket is provided with a first sliding member, and an end of the second arm close to the ladder body is provided with a second sliding member.

[0009] According to an exemplary embodiment of the present invention, the fixed bracket is provided with a first slide groove corresponding to the first sliding member; the side wall of the ladder body is provided with a second slide groove corresponding to the second sliding member; the first sliding member can slide along the first slide groove, and the second sliding member can slide along the second slide groove, thereby driving the support arm to change the support length.

[0010] According to an exemplary embodiment of the present invention, the control assembly includes: a first mounting bracket, which is arranged on a wall outside the elevator shaft; a second mounting bracket, which is arranged on the wall of the elevator shaft; an operating component, which is arranged on the first mounting bracket and is provided with a pull rope, and the pull rope is connected to the second arm of one group of support arms; and at least one return spring, one end of which is connected to the second mounting bracket and the other end of which is connected to the ladder body; wherein, through the operation of the operating component, the first sliding member of the second arm slides upward along the first sliding groove, and the second sliding member slides downward along the second sliding groove, so that the ladder body and the wall are at the farthest distance; or, through the operation of the operating component and the cooperation of the return spring, the first sliding member of the second arm slides downward along the first sliding groove, and the second sliding member slides upward along the second sliding groove, so that the ladder body and the wall are at the shortest distance.

[0011] According to an exemplary embodiment of the present invention, a pull rope passing hole is provided at the upper portion of the first mounting bracket, and the operating component further includes: a roller, which has a rotating shaft and is rotatably connected to the first mounting bracket through the rotating shaft; a pull rod, which is provided on the roller and is provided with a pull rope fixing hole at a position close to the roller; a pull rod clamping portion, which is provided at the lower portion of the first mounting bracket and is provided with a clamp corresponding to the pull rod; wherein one end of the pull rope is fixedly connected to the pull rod through the pull rope fixing hole, and the other end of the pull rope can pass through the roller and be connected to the second arm of one group of support arms through the pull rope passing hole.

[0012] According to an exemplary embodiment of the present invention, a rope sleeve is provided on the outside of the rope, a self-resilient component is provided at the end of the rope sleeve, and the self-resilient component and the other end of the rope are connected together to an end of the second arm close to the fixed bracket.

[0013] According to an exemplary embodiment of the present invention, the elevator pit ladder further includes a first switch, which is arranged on the second mounting bracket and has a first contact base and a first spring contact; when the ladder body is at the shortest distance from the wall, the first spring contact contacts with the contact of the first contact base, so that the first switch is turned on, and the elevator runs normally; when the ladder body is at the farthest distance from the wall, the first spring contact disengages from the contact of the first contact base, so that the first switch is turned off, and the elevator stops running.

[0014] According to an exemplary embodiment of the present invention, the elevator pit ladder further includes a control box, which includes: a box body, which is configured as a accommodating space formed by an inward recess of the wall, the first mounting bracket is arranged in the box body and the box body is provided with a through hole at a position corresponding to the hole through which the pull rope passes; and a box cover, which can be rotatably connected to one side of the box body and is used to close the box body.

[0015] According to an exemplary embodiment of the present invention, the control box further includes: a box lock, which is arranged at a position of the box cover corresponding to the middle of the other side of the box body, and the box lock has a keyhole exposed to the outside through the box cover; and a second switch, which is arranged in the box body and has a second contact base and a second spring contact; wherein, when the box cover is closed, the second spring contact contacts with the contact of the second contact base, so that the second switch is turned on, so that the elevator operates normally; when the box cover is opened, the second spring contact is out of contact with the contact of the second contact base, so that the second switch is turned off, so that the elevator stops running.

[0016] According to an exemplary embodiment of the present invention, the at least one group of support arms includes a first group of support arms, a second group of support arms, a third group of support arms, a fourth group of support arms, a fifth group of support arms and a sixth group of support arms; the first group of support arms is connected to one side of the upper part of the ladder body, and the second group of support arms is symmetrically connected to the other side of the upper part of the ladder body; the third group of support arms is connected to one side of the middle part of the ladder body, and the fourth group of support arms is symmetrically connected to the other side of the middle part of the ladder body; the fifth group of support arms is connected to one side of the lower part of the ladder body, and the sixth group of support arms is symmetrically connected to the other side of the lower part of the ladder body.

[0017] The elevator pit ladder of the present invention uses a control component to control the support length of the support arm so that the distance between the ladder body and the wall varies between the farthest distance and the closest distance, thereby not only enabling workers to enter and exit the pit safely but also occupying a smaller pit space.

[0018] At the same time, the elevator pit ladder of the present invention avoids the situation where workers use their arms or tools to reach into the pit to unfold the ladder body by installing the operating components on the wall outside the elevator shaft, thereby improving the convenience of use.

[0019] The device of the present invention has other characteristics and advantages, which will be obvious from the drawings and subsequent embodiments incorporated herein, or will be described in detail in the drawings and subsequent embodiments incorporated herein, which together are used to explain the specific principles of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of the overall structure of an elevator pit ladder according to an implementation scheme of the present invention, which is installed on a wall and the ladder body is at the shortest distance from the wall.

[0021] Figure 2 This is a schematic diagram of the local structure of the elevator pit ladder according to the implementation scheme of the present invention, where the ladder body and the wall are at the farthest distance.

[0022] Figure 3 This is a schematic diagram of the local structure of the elevator pit ladder according to the implementation scheme of the present invention, where the ladder body and the wall are at the shortest distance.

[0023] Figure 4 This is another partial structural schematic diagram of an elevator pit ladder according to an implementation scheme of the present invention, in which the ladder body and the wall are at the farthest distance.

[0024] Figure 5 It is a partially enlarged schematic diagram of the elevator pit ladder according to the implementation scheme of the present invention, where the ladder body and the wall are at the farthest distance.

[0025] Figure 6 It is a schematic diagram of the partial structure of the control assembly of the elevator pit ladder according to the implementation scheme of the present invention.

[0026] Figure 7 It is a schematic diagram of the cooperation between the self-resilient component of the elevator pit ladder, the pull rope and the second arm according to the embodiment of the present invention.

[0027] Description of reference numerals:

[0028] 100: Fixed bracket

[0029] 110: First chute

[0030] 200: Support arm

[0031] 201: first set of support arms 202: second set of support arms

[0032] 203: The third support arm 204: The fourth support arm

[0033] 205: fifth support arm 206: sixth support arm

[0034] 210: First arm 220: Second arm

[0035] 221: first sliding member 222: second sliding member

[0036] 300: Ladder body

[0037] 310: Second chute

[0038] 400: Control components

[0039] 410: first mounting bracket 420: second mounting bracket

[0040] 430: Operating part 431: Pull rope

[0041] 432: Self-rebound component 433: Roller

[0042] 434: Rotating shaft 435: Pull rod

[0043] 436: Drawstring fixing hole 437: Drawbar locking part

[0044] 438: Bayonet 439: Drawstring through hole

[0045] 440: Return spring 450: Pull rope sleeve

[0046] 500: First switch

[0047] 510: first contact base 520: first spring contact

[0048] 600: Control box

[0049] 610: Box body 620: Box cover

[0050] 630: Box lock 631: Keyhole

[0051] 640: second switch 641: second contact base

[0052] 642: Second spring contact.

[0053] It should be understood that the drawings are not necessarily drawn to scale, but rather present simplified representations of various features to illustrate the basic principles of the present invention. The specific design features disclosed in the present invention (including, for example, specific dimensions, directions, locations, and shapes) will be determined in part by the specific intended application and use environment.

[0054] In the figures, like reference numbers refer to the same or equivalent parts of the present invention throughout the several figures of the drawing. DETAILED DESCRIPTION

[0055] The following will be referred to in detail various embodiments of the present invention, examples of which are presented in the accompanying drawings and described below. Although the present invention will be described in conjunction with exemplary embodiments, it should be understood that this specification is not intended to limit the present invention to these exemplary embodiments. On the contrary, the present invention is intended to cover not only these exemplary embodiments, but also various alternative forms, modifications, equivalent forms and other embodiments that can be included in the spirit of the present invention and within the scope defined by the appended claims.

[0056] Combine the following Figures 1 to 7 The structure of the elevator pit ladder according to the embodiment of the present invention is described.

[0057] Figure 1 This is a schematic diagram of the overall structure of an elevator pit ladder according to an implementation scheme of the present invention, which is installed on a wall and the ladder body is at the shortest distance from the wall. Figure 2 This is a schematic diagram of the local structure of the elevator pit ladder according to the implementation scheme of the present invention, where the ladder body and the wall are at the farthest distance.

[0058] like Figure 1 and Figure 2 As shown, the elevator pit ladder according to the embodiment of the present invention includes: at least one fixed bracket 100, at least one set of support arms 200, a ladder body 300 and a control assembly 400.

[0059] At least one fixing bracket 100 is disposed on the wall of the elevator shaft and is used to fix the support arm 200 and the ladder body 300. Specifically, the fixing bracket 100 can be installed on any wall of the elevator pit by means of anchor bolts.

[0060] One end of at least one set of support arms 200 is connected to the fixed bracket 100 and can change the support length. The ladder body 300 is connected to the other end of the support arm 200. By changing the support length of the support arm 200, the support arm 200 can drive the ladder body 300 to approach or move away from the wall, so that the distance between the ladder body 300 and the wall changes between the farthest distance and the closest distance.

[0061] Specifically, in an exemplary embodiment of the present invention, Figure 1 and Figure 2As shown, at least one group of support arms 200 may include a first group of support arms 201, a second group of support arms 202, a third group of support arms 203, a fourth group of support arms 204, a fifth group of support arms 205, and a sixth group of support arms 206. The first group of support arms 201 is connected to one side of the upper portion of the ladder body 300, and the second group of support arms 202 is symmetrically connected to the other side of the upper portion of the ladder body 300. The third group of support arms 203 is connected to one side of the middle portion of the ladder body 300, and the fourth group of support arms 204 is symmetrically connected to the other side of the middle portion of the ladder body 300. The fifth group of support arms 205 is connected to one side of the lower portion of the ladder body 300, and the sixth group of support arms 206 is symmetrically connected to the other side of the lower portion of the ladder body 300. It should be clear that, according to actual needs, the support arms 200 can also include more groups. For example, when the pit is deep, the support arms 200 can also include a seventh group of support arms and an eighth group of support arms, so that the ladder body 300 can be better supported, so that the elevator pit ladder of the present invention has better stability.

[0062] According to an exemplary embodiment of the present invention, Figures 1 to 4 As shown, each of at least one group of support arms 200 may include a first arm 210 and a second arm 220. The two ends of the first arm 210 are hinged to the fixed bracket 100 and the ladder body 300, respectively. The middle part of the second arm 220 is hinged to the middle part of the first arm 210, and forms a scissor structure with the first wall 210. A first sliding member 221 is provided at one end of the second arm 220 close to the fixed bracket 100, and a second sliding member 222 is provided at one end of the second arm 220 close to the ladder body 300. The fixed bracket 100 is provided with a first slide groove 110 corresponding to the first slide member 221. The side wall of the ladder body 300 is provided with a second slide groove 310 corresponding to the second slide member 222. The first slide member 221 can slide along the first slide groove 110, and the second slide member 222 can slide along the second slide groove 310, thereby driving the support arm 200 to change the support length. Specifically, the first sliding member 221 and the second sliding member 222 may be two sliding pins, one end of the sliding pin is connected to the second arm 220 , and the other end of the sliding pin may slide along the first sliding groove 110 and the second sliding groove 310 .

[0063] Specifically, Figure 3 and Figure 4 As shown, the first slide groove 110 and the second slide groove 310 extend in the vertical direction respectively, and when the first sliding member 221 slides upward along the first slide groove 110 and the second sliding member 222 slides downward along the second slide groove 310, the support length of the support arm 200 becomes longer, and when the first sliding member 221 slides downward along the first slide groove 110 and the second sliding member 222 slides upward along the second slide groove 310, the support length of the support arm 200 becomes shorter.

[0064] The control assembly 400 is connected to the support arm 200 and is capable of controlling the support length of the support arm 200 so that the distance between the ladder body 300 and the wall varies between the farthest distance and the closest distance.

[0065] Specifically, in an exemplary embodiment of the present invention, Figure 1 , Figure 3 and Figure 4 As shown, the control assembly 400 includes a first mounting bracket 410 , a second mounting bracket 420 , an operating member 430 and at least one return spring 440 .

[0066] The first mounting bracket 410 can be set on the wall outside the elevator shaft and is used to install and fix the operating component 430. The operating component 430 is provided with a pull rope 431, and the pull rope 431 is connected to the second arm 220 of one set of support arms. The upper part of the first mounting bracket 410 is provided with a pull rope passing hole 439.

[0067] Further, the operating component 430 includes a roller 433, a pull rod 435 and a pull rod stopper 437. The roller 433 has a rotating shaft 434 and is rotatably connected to the first mounting bracket 410 through the rotating shaft 434. The pull rod 435 is provided on the roller 433, and the roller 433 can be rotated along the rotating shaft 434 by pulling the pull rod 435. The pull rod 435 is provided with a pull rope fixing hole 436 at a position close to the roller 433, so that one end of the pull rope 431 is fixed to the pull rod 435 through the pull rope fixing hole 436. The pull rod stopper 437 is provided at the lower part of the first mounting bracket 410 and is provided with a bayonet 438 corresponding to the pull rod 435. The pull rod 435 can be fixed by the pull rod stopper 437 through the bayonet 438. The other end of the pull rope 431 can pass through the roller 433 and be connected to the second arm 220 of one group of support arms through the pull rope passing hole 439.

[0068] The second mounting bracket 420 is disposed on the wall of the elevator shaft. One end of the return spring 440 is connected to the second mounting bracket 420, and the other end of the return spring 440 is connected to the ladder body 300. Specifically, in an exemplary embodiment of the present invention, as Figure 4 and Figure 5 As shown, the second mounting bracket 420 is disposed above the fixed bracket 100. The number of the second mounting brackets 420 can be set to two and correspond to the two sides of the upper end of the ladder body 300. Correspondingly, the number of the return springs 440 is also set to two, and one return spring 440 is connected to one second mounting bracket 420 and one side of the corresponding upper end of the ladder body 300, and the other return spring 440 is connected to the other second mounting bracket 420 and the other side of the corresponding upper end of the ladder body 300.

[0069] The operation of the operating member 430 can make the ladder body 300 be at the farthest distance from the wall. In other words, the operation of the operating member 430 can unfold the ladder body 300.

[0070] In general, if Figure 3 As shown, the pull rod 435 is in the first position, and the return spring 440 is in the natural state. At this time, the ladder body 300 is at the shortest distance from the wall. The staff can pull the pull rod 435 of the operating component 430 downward outside the elevator shaft, so that the pull rod 435 drives the roller 433 to rotate counterclockwise around the rotating shaft 434. At the same time, the pull rope 431 fixed on the pull rod 435 is pulled and passes through the roller 433, thereby driving the second arm 220 of one group of support arms, so that the first sliding member 221 of the second arm 220 slides upward along the first slide groove 110, and the second sliding member 222 slides downward along the second slide groove 310, so that the ladder body 300 is at the farthest distance from the wall. The staff can fix the pull rod 435 by the pull rod stopper 437 through the bayonet 438, so that the state of the ladder body 300 being at the farthest distance from the wall is stable, so that the staff can safely enter and exit the elevator pit through the ladder body 300. At this time, the pull rod 435 is in the second position (eg Figure 4 As shown), the return spring 440 is in a state of being stretched to its longest length.

[0071] After using the ladder body 300, the ladder body 300 can be at the shortest distance from the wall by operating the operating member 430 and cooperating with the return spring 440. In other words, the ladder body 300 can be folded by operating the operating member 430 and cooperating with the return spring 440.

[0072] Specifically, the staff can pull the pull rod 435 of the operating component 430 upward outside the elevator shaft, so that the pull rod 435 is disengaged from the pull rod stopper 437 through the bayonet 438. At this time, under the action of the gravity of the ladder body 300 itself and the elastic restoring force of the return spring 440, the first sliding member 221 of the second arm 220 slides downward along the first slide groove 110, and the second sliding member 222 slides upward along the second slide groove 310, so that the ladder body 300 is at the shortest distance from the wall. In this process, the pull rope 431 can pull the pull rod 435 under the drive of the second arm 220 of one set of support arms, so that it drives the roller 433 to rotate in the clockwise direction around the rotating shaft 434 until the pull rod 435 returns to the first position. At this time, the return spring 440 returns to the natural state.

[0073] The elevator pit ladder of the present invention uses a control component 400 to control the support length of the support arm 200, so that the distance between the ladder body 300 and the wall changes between the farthest distance and the closest distance, thereby not only enabling workers to enter and exit the pit safely, but also only occupying a small pit space. At the same time, the elevator pit ladder of the present invention avoids the situation where workers use their arms or tools to reach into the pit to unfold the ladder body 300 by installing the operating component 430 to the wall outside the elevator shaft, thereby improving the convenience of use.

[0074] According to an exemplary embodiment of the present invention, Figure 7 As shown, a pull rope sleeve 450 is provided on the outside of the pull rope 431. A self-resilient component 432 is provided at the end of the pull rope sleeve 450, and the self-resilient component 432 and the other end of the pull rope 431 are connected together to an end of the second arm 220 close to the fixed bracket 100. When the pull rod 435 is in the first position, the self-resilient component 432 is in a natural state. When the staff pulls the pull rod 435 downward so that the pull rod 435 drives the roller 433 to rotate counterclockwise around the rotating shaft 434, the other end of the pull rope 431 drives the self-resilient component 432 to be compressed until the pull rod 435 is in the second position, and the self-resilient component 432 is compressed to the shortest state. When the staff pulls the pull rod 435 upwards, so that the pull rod 435 is disengaged from the pull rod stopper 437 through the bayonet 438, under the action of the gravity of the ladder body 300 itself and the elastic restoring force of the return spring 440, the first sliding member 221 of the second arm 220 slides downward along the first slide groove 110, and the second sliding member 222 slides upward along the second slide groove 310, so that the ladder body 300 is at the shortest distance from the wall. At this time, the self-rebounding component 432 returns to a natural state. Preferably, in an exemplary embodiment of the present invention, the self-rebounding component 432 can be set as a spring. However, it should be clear that the structure of the self-rebounding component 432 is not limited to this, and it can be any form in the prior art as long as it can achieve the above-mentioned function.

[0075] According to an exemplary embodiment of the present invention, Figure 3 and 5As shown, the elevator pit ladder of the embodiment of the present invention further includes a first switch 500. The first switch 500 is arranged on the second mounting bracket 420. Specifically, the first switch 500 is arranged at a position of the second mounting bracket 420 corresponding to the other side of the upper part of the ladder body 300. The first switch 500 has a first contact base 510 and a first spring contact 520, and when the ladder body 300 is at the shortest distance from the wall, the other side of the upper part of the ladder body 300 can be pressed against the first spring contact 520, so that the first spring contact 520 contacts the contact of the first contact base 510, so that the first switch 500 is turned on and the elevator operates normally. When the ladder body 300 is at the farthest distance from the wall, the first spring contact 520 loses the pressing force of the ladder body 300, so that the first spring contact 520 is out of contact with the contact of the first contact base 510, so that the first switch 500 is turned off and the elevator stops running. In this way, when the workers use the ladder body 300 to enter and exit the pit, the elevator is in a stopped state, thereby ensuring the safety of the workers' operations.

[0076] According to an exemplary embodiment of the present invention, as 1 and Figure 6 As shown, the elevator pit ladder of the embodiment of the present invention further includes a control box 600. The control box 600 may include a box body 610 and a box cover 620. The box body 610 is set as a receiving space formed by the inward depression of the wall and is used to accommodate the first mounting bracket 410 and a partial structure of the operating component 430. The wall is a wall outside the elevator shaft. A through hole (not shown in the figure) is provided at the position of the box body 610 corresponding to the pull rope through hole 439, so that the other end of the pull rope 431 can pass through the wall where the box body 610 is located and is connected to the end of the second arm 220 close to the fixed bracket 100. The box cover 620 can be rotatably connected to one side of the box body 610 and is used to close the box body 610.

[0077] According to an exemplary embodiment of the present invention, Figure 6 As shown, the control box 600 further includes a box lock 630 and a second switch 640. The box lock 630 is disposed at a position of the middle of the box cover 620 corresponding to the other side of the box body 610, and the box lock 630 has a key hole 631 exposed to the outside through the box cover 620. The staff can open and close the box lock 630 by cooperating with the key and the key hole 631, thereby opening and closing the box cover 620 of the control box 600.

[0078] The second switch 640 is arranged on the box body 610. Specifically, the second switch 640 is arranged on the corner of the other side of the box body 610. The second switch 640 has a second contact base 641 and a second spring contact 642, and when the box cover 620 is closed, the position of the box cover 620 corresponding to the corner of the other side of the box body 610 can be pressed against the second spring contact 642, so that the second spring contact 642 contacts the contact of the second contact base 641, so that the second switch 640 is turned on and the elevator operates normally. When the box cover 620 is opened, the second spring contact 642 loses the pressing force of the box cover 620, so that the second spring contact 642 is out of contact with the contact of the second contact base 641, so that the second switch 640 is disconnected and the elevator stops running. In this way, when the staff opens the control box 600 to unfold the ladder body 300, the elevator can be stopped, which further ensures the safety of the staff's operation.

[0079] The operation of the elevator pit ladder according to the implementation scheme of the present invention will be described below in conjunction with the accompanying drawings.

[0080] In general, if Figure 1 and Figure 2 As shown, the ladder body 300 of the elevator pit ladder is at the shortest distance from the wall, the pull rod 435 is in the first position, the return spring 440 is in the natural state, the self-rebound component 432 is in the natural state, the first switch 500 and the second switch 640 are turned on, and the elevator operates normally.

[0081] When the staff needs to enter the pit for operation, first, the staff opens the box lock 630 by using the key and the keyhole 631 outside the elevator shaft, and thereby opens the box cover 620 of the control box 600. At this time, the second spring contact 642 of the second switch 640 is disconnected from the contact of the second contact base 641, so that the second switch 640 is disconnected and the elevator stops running.

[0082] Then, the staff member pulls down the pull rod 435 of the operating component 430, so that the pull rod 435 drives the roller 433 to rotate counterclockwise along the rotating shaft 434. At the same time, the pull rope 431 fixed on the pull rod 435 is tightened and passes through the roller 433, thereby pulling the second arm 220 of one set of support arms, so that the first sliding member 221 of the second arm 220 slides upward along the first slide groove 110, and the second sliding member 222 slides downward along the second slide groove 310, so that the ladder body 300 is at the farthest distance from the wall. In this process, the first switch 500 is disconnected, so that the elevator continues to remain in a stopped state. In this way, the second switch 640 is turned on due to the box cover 620 being mistakenly closed when the staff member is working in the pit, so that the elevator can operate normally, and the safety of the staff member's operation is further guaranteed.

[0083] Finally, the staff can fix the pull rod 435 by the pull rod stopper 437 through the bayonet 438, so that the state of the ladder body 300 being at the farthest distance from the wall is stable. At this time, the staff can enter the pit through the ladder body 300 to work.

[0084] When the staff completes the work in the pit and comes out of the pit along the ladder body 300, first, the staff can pull the pull rod 435 of the operating component 430 upward outside the elevator shaft, so that the pull rod 435 is disengaged from the pull rod stopper 437 through the bayonet 438. At this time, under the combined action of the elastic force of the self-resilient component 432, the gravity of the ladder body 300 itself and the elastic restoring force of the reset spring 440, the first sliding member 221 of the second arm 220 slides downward along the first slide groove 110, and the second sliding member 222 slides upward along the second slide groove 310, so that the ladder body 300 is at the shortest distance from the wall. In this process, the pull rope 431 can pull the pull rod 435 under the drive of the second arm 220 of one set of support arms, so that it drives the roller 433 to rotate clockwise along the rotating shaft 434 until the pull rod 435 returns to the first position. At this time, the return spring 440 returns to the natural state, the self-rebound component 432 returns to the natural state, and the first switch 500 is turned on.

[0085] Then, the staff closes the box cover 620 of the control box 600 outside the elevator shaft. At this time, the second spring contact 642 of the second switch 640 contacts the contact of the second contact base 641, so that the second switch 640 is turned on. At this time, both the first switch 500 and the second switch 640 are turned on, and the elevator runs normally.

[0086] Finally, the staff closes the box lock 630 by using the key and the keyhole 631 to close the box cover 620 of the control box 600 .

[0087] For convenience of interpretation and precise definition of the appended claims, the terms "upper", "lower", "inner", "outer", "above", "below", "upper end", "lower end", "outside", "inner", "outer", "inner", "external", "upwardly", and "downwardly" are used to describe the features of the exemplary embodiments with reference to the positions of these features shown in the accompanying drawings.

[0088] The foregoing description of the specific exemplary embodiments of the present invention is presented for the purpose of illustration and description. The foregoing description is not intended to be exhaustive, nor is it intended to limit the present invention to the precise form disclosed, and it is apparent that many changes and variations are possible in accordance with the above teachings. The exemplary embodiments are selected and described to explain the specific principles of the present invention and its practical application, so that other technical personnel in the art can realize and utilize the various exemplary embodiments of the present invention and its different selected forms and modified forms. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An elevator pit ladder, characterized in that: include: At least one fixed bracket, which is arranged on the wall of the elevator shaft; at least one set of support arms, one end of which is connected to the fixed bracket and capable of changing the support length; a ladder body connected to the other end of the support arm; as well as A control assembly is connected to the support arm and is capable of controlling the support length of the support arm so that the distance between the ladder body and the wall changes between a farthest distance and a closest distance.

2. The elevator pit ladder according to claim 1, characterized in that: Each of the at least one set of support arms comprises: a first arm, two ends of which are respectively hinged to the fixed bracket and the ladder body; and The middle part of the second arm is hinged to the middle part of the first arm, one end of the second arm close to the fixed bracket is provided with a first sliding member, and one end of the second arm close to the ladder body is provided with a second sliding member.

3. The elevator pit ladder according to claim 2, characterized in that: The fixed bracket is provided with a first sliding groove corresponding to the first sliding member; The side wall of the ladder body is provided with a second sliding groove corresponding to the second sliding member; The first sliding member can slide along the first sliding groove, and the second sliding member can slide along the second sliding groove, thereby driving the support arm to change the support length.

4. The elevator pit ladder according to claim 3, characterized in that: The control component comprises: A first mounting bracket is arranged on a wall outside the elevator shaft; A second mounting bracket is arranged on the wall of the elevator shaft; an operating member disposed on the first mounting bracket and provided with a pull rope connected to a second arm of one set of support arms; and at least one return spring having one end connected to the second mounting bracket and another end connected to the ladder body; Wherein, by operating the operating component, the first sliding member of the second arm slides upward along the first sliding groove, and the second sliding member slides downward along the second sliding groove, so that the ladder body is at the farthest distance from the wall; Alternatively, through the operation of the operating component and the cooperation of the return spring, the first sliding member of the second arm slides downward along the first sliding groove, and the second sliding member slides upward along the second sliding groove, so that the ladder body is at the shortest distance from the wall.

5. The elevator pit ladder according to claim 4, characterized in that: A pull rope passing hole is provided on the upper portion of the first mounting bracket, and the operating component includes: A roller having a rotating shaft and rotatably connected to the first mounting bracket via the rotating shaft; A pull rod, which is arranged on the roller and has a pull rope fixing hole at a position close to the roller; A pull rod stopper, which is arranged at the lower part of the first mounting bracket and is provided with a bayonet corresponding to the pull rod; One end of the pull rope is fixedly connected to the pull rod through a pull rope fixing hole, and the other end of the pull rope can pass through the roller and be connected to the second arm of one group of support arms through the pull rope passing hole.

6. The elevator pit ladder according to claim 5, characterized in that: A pull rope sleeve is arranged on the outside of the pull rope, a self-resilient component is arranged on the end of the pull rope sleeve, and the self-resilient component and the other end of the pull rope are connected together to an end of the second arm close to the fixed bracket.

7. The elevator pit ladder according to claim 6, characterized in that: It further includes a first switch, which is disposed on the second mounting bracket and has a first contact base and a first spring contact; When the ladder body is at the shortest distance from the wall, the first spring contact contacts the contact of the first contact base, so that the first switch is turned on, so that the elevator operates normally; When the ladder body is at the farthest distance from the wall, the first spring contact is disconnected from the contact of the first contact base, so that the first switch is disconnected, and the elevator stops running.

8. The elevator pit ladder according to claim 7, characterized in that: It further comprises a control box, the control box comprising: A box body is provided as a receiving space formed by an inward depression of a wall body, the first mounting bracket is provided in the box body, and a through hole is provided in the box body at a position corresponding to the hole through which the pull rope passes; and The box cover is rotatably connected to one side of the box body and is used to close the box body.

9. The elevator pit ladder according to claim 8, characterized in that: The control box further comprises: a box lock provided at a position of the box cover corresponding to the middle of the other side of the box body, and having a key hole exposed to the outside through the box cover; and A second switch, which is disposed in the box and has a second contact base and a second spring contact; Among them, when the box cover is closed, the second spring contact contacts the contact of the second contact base, so that the second switch is turned on, so that the elevator runs normally; when the box cover is opened, the second spring contact is disengaged from the contact of the second contact base, so that the second switch is turned off, and the elevator stops running.

10. The elevator pit ladder according to claim 1, characterized in that: The at least one group of support arms includes a first group of support arms, a second group of support arms, a third group of support arms, a fourth group of support arms, a fifth group of support arms and a sixth group of support arms; The first set of support arms is connected to one side of the upper portion of the ladder body, and the second set of support arms is symmetrically connected to the other side of the upper portion of the ladder body; The third set of support arms is connected to one side of the middle portion of the ladder body, and the fourth set of support arms is symmetrically connected to the other side of the middle portion of the ladder body; The fifth set of support arms is connected to one side of the lower portion of the ladder body, and the sixth set of support arms is symmetrically connected to the other side of the lower portion of the ladder body.

Images