A plug door screw rod driving passive terminal locking device

Abstract

The application provides a kind of sliding plug door screw rod drive, passive terminal locking device, including screw rod, lock box and screw rod nut assembly, the screw rod nut assembly includes roller, swing arm group, swing arm, base, limiting shaft, limiting plate, torsional spring, roller seat and screw rod nut, wherein, the swing arm group is rigid swing arm body, corresponding with screw rod nut and another swing arm articulates, base and swing arm articulate, roller, limiting plate is fixed on roller seat, roller seat is fixed on screw rod nut without relative movement, torsional spring is sleeved on screw rod nut, one end of torsional spring is defined on roller seat, the other end is defined on swing arm group, limiting shaft is rotatably connected with swing arm and passes through limiting plate.After closing door, the position of screw rod nut is limited without directly limiting screw rod, such terminal locking mode can reduce the influence of vibration impact on screw rod, improve safety and reliability;Using the movement characteristics of sliding plug door plug-out and plug-in, relevant constraint trajectory is set on limiting plate, through such movement offset and trajectory constraint, the rotation around the axis of screw rod nut when moving back and forth in screw rod axial direction is limited, and the general length locking guide rail required by terminal locking is cancelled.

Description

Technical Field

[0001] This invention relates to the field of drive and locking devices in the door systems of rail vehicles and buses, and particularly to a plug door screw drive and passive terminal locking device. Background Technology

[0002] Door systems in rail vehicles and buses have various driving and locking devices, among which screw-driven mechanisms and related locking devices are currently the mainstream structure and are widely used. These screw-driven structures are further divided into two main locking methods: terminal locking and full-range locking.

[0003] The main idea behind the full-range locking system is a functional design centered around the movement of the lead screw under various door movement conditions. That is, it directly constrains or releases the lead screw.

[0004] The terminal locking mechanism, taking into account the movement characteristics of the lead screw and the door itself, employs a special constraint structure design for the lead screw, lead screw nut, and related components. This ensures a fully mechanically locked state after the door is closed. The locking mechanism itself can be further divided into the slot design on the outside of the lead screw and the lead screw itself.

[0005] Comparing the two, assuming no design flaws, each has its own characteristics and advantages in terms of functionality, complexity, maintenance costs, and safety and reliability.

[0006] In contrast, current terminal locking technologies are simple in structure and highly mechanically reliable. Some embodiments have been mature solutions for decades in domestic and international markets. However, the inherent components due to their motion characteristics still limit the simplification and optimization of the overall structure. It is impossible to further reduce costs and materials while maintaining reliability.

[0007] Based on this, the design of a new and reliable plug door screw drive and passive terminal locking device is necessary and sustainable in the current market conditions of competition and development, combined with cost and quality control. Summary of the Invention

[0008] The present invention aims to provide a screw-driven, passive terminal locking device for a sliding door, in order to overcome the shortcomings of the prior art.

[0009] To solve the above-mentioned technical problems, the technical solution of the present invention is: a screw-driven, passive terminal locking device for a sliding door, comprising a screw, a lock box, and a screw-nut assembly, characterized in that the screw-nut assembly comprises a roller, a swing arm assembly, a swing arm, a base, a limiting shaft, a limiting plate, a torsion spring, a roller seat, and a screw nut, wherein the swing arm assembly is a rigid swing arm body, which is hinged to the nut and another swing arm, the base is hinged to the swing arm, the roller and the limiting plate are fixed on the roller seat, the roller seat is fixed on the screw nut without relative movement, the torsion spring is sleeved on the screw nut, one end of the torsion spring is limited to the roller seat, and the other end is limited to the swing arm assembly, the limiting shaft passes through the limiting plate and is rotatably connected to the swing arm.

[0010] As an improvement to the passive terminal locking device for a sliding door screw drive according to the present invention, the limiting plate has a guide groove inside, which is divided into two tracks. One end of the guide groove coincides as a single point, and the other end gradually separates into two endpoints. The shorter track is arc-shaped and used for terminal locking; the longer, gradually opening arc is used for guiding and self-limiting, thereby eliminating the need for an external, continuous locking guide rail. As an improvement to the passive terminal locking device for a sliding door screw drive according to the present invention, the lock box has a slot. When the terminal is locked, the roller enters the slot and locks. Only two guide walls of different lengths cooperate with the slot, without a matching continuous guide rail to constrain the roller's movement.

[0011] As an improvement of the screw drive and passive terminal locking device for a sliding door according to the present invention, the vertical relative height between the base and the axis of the screw is a constant value.

[0012] As an improvement of the screw drive and passive terminal locking device for a sliding door in this invention, the base is used to be fixedly connected to the door leaf through one or more rigid bodies.

[0013] As an improvement of the screw-driven, passive terminal locking device for sliding doors according to the present invention, the screw-driven, passive terminal locking device for sliding doors is applicable to both single-opening and double-opening sliding door structures.

[0014] Compared with existing terminal locking technologies, the advantages of this invention are:

[0015] By utilizing the sliding door's insertion and withdrawal motion characteristics, relevant constraint trajectories are set on the limit plate. Through such motion offset and trajectory constraints, the rotation of the lead screw nut around its axis is restricted during the lead screw's axial reciprocating movement, eliminating the need for the continuous locking guide rail typically required for end locking. This reduces weight, complexity, and various costs.

[0016] Meanwhile, compared to the current full-process locking technology, the externally mounted lead screw terminal locking scheme (not the lead screw's own guide groove locking structure) has the following advantages:

[0017] The locking structure is simple and has high mechanical reliability;

[0018] Instead of directly restricting the lead screw, the various effects of vibration and impact are reduced, thereby improving safety and reliability.

[0019] The matching emergency unlocking device allows the door to be opened manually without being forced to remain in an active state, which simplifies the structure and improves mechanical reliability.

[0020] By setting up such a screw drive and terminal locking device, it can be ensured that after multiple obstacle detection functions are completed, the door enters a free state and can be opened or closed manually or electronically. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only one embodiment recorded in the present invention. For those skilled in the art, without creative effort, other derived embodiments and related illustrations can be obtained based on the principles and these drawings and descriptions.

[0022] Figure 1 This is a perspective view (front view) of the sliding door screw drive and passive terminal locking device in the locked state of the sliding door, as described in an embodiment of the present invention.

[0023] Figure 2 This is a perspective view (back view) of the sliding door screw drive and passive terminal locking device in the locked state of the sliding door, as described in an embodiment of the present invention.

[0024] Figure 3 This is a schematic diagram illustrating the self-limiting structure and key limiting structure of the screw nut assembly for a sliding door in the locked state, as described in an embodiment of the present invention.

[0025] Figure 4 This is a perspective view (front view) of the sliding door screw drive and passive terminal locking device in the sliding door sliding stage, as described in an embodiment of the present invention.

[0026] Figure 5 This is a perspective view (reverse side) of the sliding door screw drive and passive terminal locking device in the sliding door sliding stage, as described in an embodiment of the present invention.

[0027] Figure 6 This is a schematic diagram illustrating the self-limiting structure and key limiting structure of the screw nut assembly for a sliding door in the sliding door sliding stage, as described in an embodiment of the present invention.

[0028] Figure 7This is a perspective view (front view) of the sliding door screw drive and passive terminal locking device in the sliding door translation stage, according to an embodiment of the present invention.

[0029] Figure 8 This is a perspective view (back view) of the sliding door screw drive and passive terminal locking device during the sliding door translation stage in an embodiment of the present invention.

[0030] Figure 9 This is a schematic diagram illustrating the self-limiting structure and key limiting structure of the sliding door screw nut assembly in an embodiment of the present invention, during the sliding door translation stage.

[0031] in Figures 1-3 , Figures 4-6 , Figures 7-9 The three groups of diagrams represent the same state under different conditions.

[0032] The components are: 1. Lead screw; 2. Lock box; 3. Lead screw nut assembly; 4. Roller; 5. Swing arm assembly; 6. Swing arm; 7. Base; 8. Limiting shaft; 9. Limiting plate; 10. Torsion spring; 11. Roller seat. Detailed Implementation

[0033] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are merely one embodiment of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0034] like Figures 1-3 As shown, the overall structure mainly consists of a lead screw 1, a lock box 2, and a lead screw and nut assembly 3. The main components of the lead screw and nut assembly 3 include rollers 4, swing arm assembly 5, swing arm 6, base 7, limiting shaft 8, limiting plate 9, torsion spring 10, roller seat 11, and the core lead screw and nut. The two axes of the swing arm assembly 5 are hinged to the lead screw and nut and the swing arm 6 respectively, and the base 7 is hinged to the other end of the swing arm 6. Rollers 4 and the limiting plate 9 are fixed to the roller seat 11 and are fixed to the lead screw and nut, remaining relatively stationary. The torsion spring 10 is fitted onto the lead screw and nut, with one end limited to the roller seat 11 and the other end limited to the swing arm assembly 5. The limiting shaft 8 passes through the groove of the limiting plate 9 and is fixed to the swing arm 6, allowing free rotation.

[0035] The limiting plate has a specially designed guide groove inside, which has two tracks. One end of the guide groove coincides as a single point, while the other end gradually separates into two endpoints. The shorter track is arc-shaped and used for final locking; the longer, involute arc is used for self-limiting guidance, thus eliminating the need for an external, continuous locking guide rail. This involute arc track is a specific curve equation derived based on the established relative motion position relationship. The lock box 2 has a slot; when the final lock is engaged, the roller enters the slot for locking. Only two guide walls of different lengths cooperate with the slot; there is no continuous guide rail to constrain the roller's movement.

[0036] The swing arm assembly 5 is provided with a connecting plate, which is threadedly connected to the swing arm assembly 5. It is simply represented as a rigid swing arm body.

[0037] The base 7 is used for fixed connection to the door leaf via one or more rigid bodies (usually door carriers).

[0038] Overall, the two ends of the lead screw 1 are fixed in the matching mechanism, allowing only rotation around its axis without relative movement. The lock box 2 is fixed in the same mechanism. The base 7 is fixed to a device (usually a door carrier) that can move the door leaf in and out. Due to the inherent movement limitations of such a device, Figure 3 , Figure 6 , Figure 9 From a vantage point of view, the base 7 can only move left and right. That is, the base 7 remains horizontal at any position throughout the sliding door's movement, and its vertical relative height to the axis of the lead screw 1 remains constant. The limiting shaft 8 moves back and forth within the groove of the limiting plate 9 due to the door's insertion and removal motion. Because of this constraint, the roller 4 remains in an upward position throughout the entire movement, without a continuous guide rail, until it rotates into the locking slot of the lock box 2.

[0039] Detailed explanation is as follows:

[0040] The motor drives the lead screw 1 as a power source, such as... Figure 1 As shown, rotate in direction A to open the door or rotate in direction B to close the door.

[0041] When the motor drives the rotation in direction A, such as Figure 1 As shown, due to its structural characteristics, lead screw 1 has two component forces F at any given time. Ax F Ar The purpose is to push and rotate the lead screw nut in the lead screw nut assembly 3. Wherein F... Ax For the moving thrust, F Ar The generated torque is rotational power. When in the locked state ( Figures 1-3 The roller 4 on the lead screw nut assembly 3 is restricted by the slot of the lock box 2 and cannot move axially along the lead screw 1. Meanwhile, due to F... ArThe function is that the lead screw 1 overcomes the torque of the torsion spring 10, causing the lead screw nut to rotate in place until the roller 4 enters the guide groove of the lock box 2. Figure 4 At this point, the limiting shaft 8 and the limiting plate 9 have already moved from... Figure 3 The state has entered Figure 6 Status. Simultaneously, the entire lead screw and nut assembly 3 is affected by F. Ax The action begins with axial movement. At this point, depending on the speed, if F... Ar The generated torque is greater than the torque of the torsion spring 10. The roller 4 abuts against the short guide wall of the lock box 2. After the roller 4 leaves the short guide wall of the lock box 2, the lower edge of the limiting shaft 8 abuts against the groove of the limiting plate 9; if F Ar The generated torque is less than the torque of the torsion spring 10. When roller 4 just enters the guide groove of lock box 2, it abuts against the long guide wall of lock box 2. After disengaging from the long guide wall, the upper edge of the limiting shaft 8 abuts against the groove of the limiting plate 9. Therefore, when the lead screw nut moves axially, roller 4 always moves upward and does not rotate relative to the axis of the lead screw 1. This state completes the insertion and translation of the sliding door. Figures 7-9 (Until the door is fully open.)

[0042] When the motor drives the rotation in direction B, such as Figure 1 As shown, due to its structural characteristics, lead screw 1 has two component forces F at any given time. Bx F Br The purpose is to push and rotate the lead screw nut in the lead screw nut assembly 3. Wherein F... Bx For the moving thrust, F Br The resulting torque is rotational power. For example... Figures 7-9 As shown, the sliding door is currently in the translation phase, due to F Br The resulting torque and the torque of the torsion spring 10 cause the upper edge of the limiting shaft 8 to abut against the groove of the limiting plate 9. Figure 9 Therefore, during the movement of the lead screw and nut assembly 3, roller 4 remains upward without contacting any external object, maintaining its position relative to the lead screw axis without rotating. This continues until the sliding door is inserted, also due to F... Br Under the combined torque of the generated torque and the torque of the torsion spring 10, roller 4 abuts against the long guide wall of lock box 2. The lead screw nut is still driven by lead screw 1 to move axially without rotating, so roller 4 remains upward and does not rotate. When the axial movement is about to reach the bottom ( Figures 4-6 ), the long guide wall ends, because F Br The generated torque and the torque of the torsion spring 10 cause the lead screw 1 to drive the lead screw nut and roller 4 into the slot of the lock box 2. At this time, the sliding door is completely locked.

[0043] When there is no motor power source, in the closed and locked position, manual unlocking overcomes the torque of the torsion spring 10, causing the roller 4 to rotate out of the slot in the lock box 2 and contact the long guide wall of the lock box 2. At this time, the sliding door is in the free position, and the screw nut assembly 3 can move axially on the screw 1, allowing the sliding door to be opened and closed manually. At this time, the screw nut assembly 3 is the driving member, and the screw 1 is the driven member.

[0044] When the door is opened manually, the lead screw 1 is pushed by the lead screw and nut assembly 3 and rotates in direction A. The lead screw and nut in the lead screw and nut assembly 3 are always subjected to the reaction force F generated by the lead screw 1 tending to remain in its original position. Bx F Br .

[0045] During the stage of the Slammer door being pushed out ( Figures 4-6 ), due to F Br The resulting torque, along with the torque of the torsion spring 10, causes the roller 4 to press against the long guide wall on the lock box 2, keeping the roller 4 in an upward position and preventing it from rotating relative to the axis of the lead screw 1.

[0046] During the Sierra door translation phase ( Figures 7-9 ), subject to F Br The resulting torque, influenced by the torque of the torsion spring 10, causes the upper edge of the limiting shaft 8 to abut against the groove of the limiting plate 9. Figure 9 Roller 4 therefore remains in contact and always faces upwards, continuing to remain stationary relative to the axis of screw 1.

[0047] When the door is manually closed, the lead screw 1 is pushed by the lead screw and nut assembly 3 and rotates in the direction B. The lead screw and nut in the lead screw and nut assembly 3 are always subjected to the reaction force F generated by the lead screw 1 tending to remain in its original position. Ax F Ar .

[0048] In the translation of the Sela door ( Figures 7-9 ) and insertion stage ( Figures 4-6 ), because F Ar The resulting torque effect, when F Ar The generated torque is greater than the torque of the torsion spring 10, and the lower edge of the limiting shaft 8 abuts against the groove of the limiting plate 9 until the roller 4 contacts the short guide wall of the lock box 2. When F Ar The generated torque is less than the torque of the torsion spring 10. The upper edge of the limiting shaft 8 abuts against the groove of the limiting plate 9 until the roller 4 contacts the long guide wall of the lock box 2. When it is fully closed, no more F is generated. Ax F Ar Meanwhile, the lead screw nut is constantly subjected to the torque of the torsion spring 10, pushing the roller 4 into the slot of the lock box 2, thus fully locking the sliding door. Throughout the entire movement before the locking process, the roller 2 remains upward and does not rotate relative to the axis of the lead screw 1.

[0049] When there is no external power source, in any non-locked position, due to the torque of the torsion spring 10, the upper edge of the limiting shaft 8 abuts against the groove of the limiting plate 9, or the roller 4 abuts against the long guide wall of the lock box 2. Therefore, the roller 4 always remains upward and does not rotate relative to the axis of the lead screw 1.

[0050] The above is based on Figures 1-9 The detailed description of one embodiment also applies to a mirrored structure where the door opening direction changes. It also applies to double-opening sliding door structures, where the entire structure can be mirrored left and right along or near the door system centerline, and driven and locked synchronously.

[0051] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or fundamental principles of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0052] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A screw-driven, passive terminal locking device for a sliding door, comprising a screw, a lock box, and a screw-nut assembly, characterized in that, The lead screw and nut assembly includes a roller, a swing arm assembly, a swing arm, a base, a limiting shaft, a limiting plate, a torsion spring, a roller seat, and a lead screw and nut. The swing arm assembly is a rigid swing arm body that is hinged to the nut and another swing arm. The base is hinged to the swing arm. The roller and the limiting plate are fixed on the roller seat. The roller seat is fixed on the lead screw and nut and has no relative movement. The torsion spring is sleeved on the lead screw and nut. One end of the torsion spring is limited to the roller seat, and the other end is limited to the swing arm assembly. The limiting shaft passes through the limiting plate and is rotatably connected to the swing arm. The limiting plate has a guide groove inside, which is divided into two tracks. One end of the guide groove coincides as a single point, and the other end gradually separates into two endpoints. The shorter track is arc-shaped and used for terminal locking; the longer, gradually opening arc is used for guiding and self-limiting, thereby eliminating the need for an external, continuous locking guide rail.

2. The plug door screw drive and passive terminal locking device according to claim 1, characterized in that, The lock box is equipped with a slot. When the terminal is locked, the roller enters the slot and locks. Only two guide walls of different lengths cooperate with the slot, but there is no matching full-length guide rail to constrain the roller's movement.

3. The plug door screw drive and passive terminal locking device according to claim 1, characterized in that, The vertical relative height between the base and the axis of the lead screw is a constant.

4. The plug door screw drive and passive terminal locking device according to claim 1, characterized in that, The base is fixedly connected to the door leaf via one or more rigid bodies.

5. A plug door screw drive and passive terminal locking device according to claim 1, characterized in that, This screw-driven, passive terminal locking device for sliding doors is suitable for both single-opening and double-opening sliding door structures.

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