A slide rail counterweight device

Abstract

The utility model discloses a slide rail counterweight device, including conveying track, guide component, energy storage pipe fitting and counterweight, guide component includes two interval symmetrical setting guide rail, and the length direction of guide rail is equipped with the sliding slot of energy storage pipe fitting embedding slide along conveying track, and the both ends of energy storage pipe fitting are embedded in the sliding slot of both sides guide rail respectively, the below of guide component is provided with guide pulley, and the below of guide pulley is equipped with counterweight, the sliding slot includes the sliding start of energy storage pipe fitting and slide, and the guide pulley includes a plurality of interval setting guide wheel, and the below interval setting of guide wheel from sliding start, the both ends of energy storage pipe fitting are provided with directional pulley, and directional pulley is passed through the transmission connection of the guide pulley and counterweight of pull rope around setting, the utility model technical scheme aims at not needing additional motor and so on power source, provides stable auxiliary for subsequent load action, improves the low energy consumption of counterweight device and operation cooperativity.

Description

Technical Field

[0001] This utility model relates to the field of automation technology, and in particular to a slide rail balancing counterweight device. Background Technology

[0002] In automated production lines, the lifting and translation of workpieces often require counterweight devices to balance the load and reduce energy consumption. However, existing mainstream counterweight systems generally rely on additional motors or hydraulic devices to provide power for auxiliary load driving. These additional power sources not only increase the manufacturing cost of the equipment but also require supporting control systems and wiring, resulting in complex equipment structures and significantly increased difficulty and cost of later maintenance. At the same time, motor drives continuously consume electrical energy, and energy loss is significant in high-frequency operation scenarios. Furthermore, fixed output power is difficult to flexibly adapt to the load requirements of workpieces of different weights, which can easily affect the counterweight balancing accuracy.

[0003] Furthermore, some existing counterweight systems without additional power, while attempting to store energy through the movement of the workpiece itself, lack targeted transmission structure design and cannot effectively utilize the kinetic energy of existing moving parts (such as transfer trolleys) in the production line. The kinetic energy of the trolley moving on the track is not recovered and utilized, and a separate drive mechanism is still required for the energy storage component. This not only wastes energy but also causes the energy storage process to be disconnected from the subsequent counterweight auxiliary drive links, failing to provide stable potential energy support for subsequent actions such as workpiece lifting and lowering, and making it difficult to meet the production line's demand for low-energy-consumption and highly coordinated counterweight devices. Utility Model Content

[0004] The main objective of this invention is to provide a slide rail balancing counterweight device that eliminates the need for additional power sources such as motors, providing stable assistance for subsequent load operations and improving the energy efficiency and operational coordination of the counterweight device. To achieve the above objectives, the present invention proposes a slide rail balancing counterweight device, which includes a conveying track, a guide component, an energy storage tube, and a counterweight. The guiding component includes two symmetrically spaced guide rails. The guide rails are provided with grooves along the length of the conveying track for the energy storage tube to be inserted and slid. Both ends of the energy storage tube are respectively embedded in the grooves of the two guide rails. A guide pulley is provided below the guide member, and the counterweight is located below the guide pulley. The chute includes a sliding start end and a sliding end end for the energy storage tube to slide, and the guide pulley includes a plurality of guide wheels spaced apart, the guide wheels being spaced apart from below the sliding start end; The energy storage pipe is equipped with directional pulleys at both ends, and the directional pulleys are connected to the counterweight via a pull rope wound around the guide pulley.

[0005] In some embodiments of this utility model, the slide rail balancing counterweight device is further provided with an auxiliary pulley, which is located below the guide member and close to the sliding end; The counterweight is connected to the balancing workpiece by a rope wound around the auxiliary pulley.

[0006] In some embodiments of this utility model, the counterweight is located below the auxiliary pulley, and the auxiliary pulley is spaced apart along the sliding end.

[0007] In some embodiments of this utility model, the sliding groove is inclined upwards from the sliding beginning end toward the sliding end end.

[0008] In some embodiments of this utility model, the guide rail further includes a second groove, which communicates with the slide groove. The energy storage tube can slide within the second groove. The second groove extends upward in a direction away from the sliding start end, and the inclination angle of the second groove is greater than the inclination angle of the slide groove.

[0009] In some embodiments of this utility model, the slide rail balancing counterweight device further includes a guide tensioning member disposed below the guide pulley and an auxiliary tensioning member disposed below the auxiliary pulley; The guide tensioning member abuts against the lower surface of the pull rope wrapped around the guide pulley; the auxiliary tensioning member abuts against the lower surface of the pull rope wrapped around the auxiliary pulley.

[0010] In some embodiments of this utility model, the guide tensioning member includes a guide tensioning wheel and a guide adjustment structure. The guide tensioning wheel is installed below the guide pulley through the guide adjustment structure, and the guide adjustment structure can adjust the relative position of the guide tensioning wheel and the guide pulley.

[0011] In some embodiments of this utility model, the auxiliary tensioning member includes an auxiliary tensioning wheel and an auxiliary adjustment structure. The auxiliary tensioning wheel is installed below the auxiliary pulley through the auxiliary adjustment structure, and the auxiliary adjustment structure can adjust the relative position of the auxiliary tensioning wheel and the auxiliary pulley.

[0012] In some embodiments of this utility model, the slide rail balancing counterweight device further includes a locking mechanism, which is installed beside the movement path of the counterweight and can abut against or separate from the counterweight.

[0013] In some embodiments of this utility model, the locking mechanism includes a pedal, an elastic element, and a locking element; the locking element is rotatably mounted on the frame of the slide rail balance counterweight device via a hinge structure, and the locking element can abut against the outer periphery of the counterweight; one end of the elastic element is drivenly connected to the locking element, and the pedal is drivenly connected to the other end of the elastic element via a pulley arranged in the locking mechanism via a pull rope.

[0014] This utility model's technical solution provides a precise embedded sliding path for the energy storage tube through the sliding grooves of two symmetrical guide rails. This ensures that the energy storage tube slides stably only along the length of the conveyor track when the trolley is pushed, without lateral deviation or jamming, thus avoiding interference with the trolley's movement path. The guide pulleys below the guide components and the counterweight form a transmission link through the pull rope. The directional pulleys at both ends of the energy storage tube optimize the force direction of the pull rope, so that when the trolley pushes the energy storage tube to slide, the counterweight can be lifted simultaneously through the pull rope, converting the kinetic energy of the trolley into the gravitational potential energy of the counterweight for storage. This eliminates the need for an additional motor to drive the energy storage process, significantly reducing energy consumption. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this utility model 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 some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0016] Figure 1 This is one of the structural schematic diagrams of the slide rail balancing counterweight device of this utility model; Figure 2 This is the second schematic diagram of the slide rail balancing counterweight device of this utility model; Figure 3 This is a partial structural schematic diagram of the slide rail balancing counterweight device of this utility model.

[0017] Explanation of icon numbers: 100. Conveying track; 200. Guide component; 210. Guide rail; 220. Slide groove; 230. Guide pulley; 300. Energy storage pipe fitting; 310. Directional pulley; 400. Counterweight; 500. Auxiliary pulley; 600. Second slot; 700. Guide tensioning component; 800. Auxiliary tensioning component; 900. Locking mechanism; 910. Pedal; 920. Elastic component; 930. Locking component; The realization of the purpose, functional features and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0018] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0019] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in this utility model embodiment are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.

[0020] Furthermore, the use of terms such as "first" and "second" in this utility model is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. If the combination of technical solutions is contradictory or impossible to implement, the user should consider such a combination of technical solutions to be non-existent and not within the scope of protection claimed by this utility model.

[0021] This utility model proposes a slide rail balancing counterweight device, including a conveying track 100, a guide component 200, an energy storage tube 300, and a counterweight 400. The guide member 200 includes two guide rails 210 arranged symmetrically at intervals. The guide rails 210 are provided with grooves 220 along the length of the conveying track 100 for the energy storage tube 300 to be inserted and slid. The two ends of the energy storage tube 300 are respectively embedded in the grooves 220 of the two guide rails 210. A guide pulley 230 is provided below the guide member 200, and a counterweight 400 is provided below the guide pulley 230; The chute 220 includes a sliding start end and a sliding end end for the energy storage tube 300 to slide, and the guide pulley 230 includes a number of guide wheels spaced apart, with the guide wheels spaced apart from below the sliding start end; The energy storage pipe fitting 300 is equipped with directional pulleys 310 at both ends. The directional pulleys 310 are connected to the counterweight 400 by a pull rope around the guide pulley 230.

[0022] Based on the above technical features, the grooves 220 of the two symmetrical guide rails 210 provide a precise embedded sliding path for the energy storage tube 300, ensuring that the energy storage tube 300 slides stably only along the length of the conveying track 100 when the trolley is pushed, without lateral deviation or jamming, thus avoiding interference with the trolley's movement path; the guide pulley 230 below the guide component 200 and the counterweight 400 form a transmission link through the pull rope, and the directional pulleys 310 at both ends of the energy storage tube 300 can optimize the force direction of the pull rope, so that when the trolley pushes the energy storage tube 300 to slide, the counterweight 400 can be driven to rise simultaneously through the pull rope, converting the kinetic energy of the trolley into the gravitational potential energy of the counterweight 400 for storage, without the need for an additional motor to drive the energy storage process, thus greatly reducing energy consumption.

[0023] In actual operation, when the trolley returns empty after transferring panels or parts, its own kinetic energy can drive the energy storage tube 300 to slide and drive the counterweight 400 to rise and store energy. Subsequently, when the production line needs to drive the balancing workpiece, the counterweight 400, which stores potential energy, can drive the energy storage tube 300 to slide in the opposite direction through a pull rope, thereby providing auxiliary power for the balancing workpiece, offsetting part of the load weight, and reducing the operating pressure on the balancing workpiece drive mechanism. The entire process relies on the coordinated mechanical structure to achieve kinetic energy recovery and potential energy utilization, which not only improves the energy utilization rate of the production line, but also ensures the stability of energy storage and transmission through gravity drive, avoiding the increase in equipment complexity and maintenance costs caused by the introduction of an additional power source, and adapting to the continuous and low-energy consumption operation requirements of the production line.

[0024] Furthermore, the slide rail balance counterweight device is also equipped with an auxiliary pulley 500, which is located below the guide member 200 and close to the sliding end. The counterweight 400 is connected to the balancing workpiece via a pull rope wound around an auxiliary pulley 500. This design avoids the sliding path of the energy storage tube 300, preventing interference between their movements, and also shortens the transmission distance of the pull rope from the counterweight 400 to the balancing workpiece, reducing the risk of slackness and entanglement due to excessive rope length. The connection between the counterweight 400 and the balancing workpiece via the pull rope wound around the auxiliary pulley 500 allows the weight of the counterweight 400 to directly act on the balancing workpiece, achieving real-time gravity compensation for the balancing workpiece.

[0025] The counterweight 400 is located below the auxiliary pulleys 500, which are spaced apart along the sliding end. The counterweight 400's location below the auxiliary pulleys 500 ensures that the direction of its gravity is completely aligned with the direction of the pull rope transmission, eliminating the need for additional pulleys to change the force direction. This reduces power transmission losses and ensures that the counterweight 400 provides more direct and efficient gravity compensation for the balancing workpiece. Simultaneously, the spaced auxiliary pulleys 500 along the sliding end allow the path of the pull rope around them to cover the entire sliding stroke of the energy storage tube 300 from the beginning to the end of the slide. This ensures that the energy storage tube 300 receives stable power from the counterweight 400 throughout the entire sliding process, preventing insufficient local power or excessive force on the pull rope due to uneven distribution of the auxiliary pulleys 500.

[0026] Furthermore, the chute 220 is inclined upwards from the sliding start end to the sliding end end. This upward inclination of the chute 220 from the sliding start end to the sliding end end allows for precise coordination of contact pushing and automatic disengagement in scenarios where a trolley pushes the energy storage tube 300 on an automated production line. When the trolley travels along the conveyor track 100 to the sliding start end, it naturally contacts the energy storage tube 300 and pushes it upwards along the inclined chute 220. During this process, the trolley's kinetic energy is converted into the gravitational potential energy of the energy storage tube 300 and the potential energy of the counterweight 400. As the chute 220 gradually rises, the energy storage tube 300 continuously rises along the inclined path, while the trolley travels along the horizontal or low-angle conveyor track 100. The height difference between the two gradually increases. When the trolley travels a preset distance, the energy storage tube 300, due to the inclination of the chute 220, has risen to a position higher than the top of the trolley, thus automatically disengaging from the trolley and preventing excessive energy storage or structural interference caused by continued trolley pushing.

[0027] In this embodiment, the guide rail 210 further includes a second slot 600, which communicates with the slide 220. The energy storage tube 300 can slide within the second slot 600. The second slot 600 extends upwards in a direction away from the sliding start end, and the inclination angle of the second slot 600 is greater than that of the slide 220. The second slot 600 communicates with the slide 220 and has a larger inclination angle in the opposite direction away from the sliding start end, forming a segmented path of gentle forward pushing and steep reverse disengagement, accurately solving the problem of rapid disengagement and interference between the trolley and the energy storage tube 300. When the trolley pushes the energy storage tube 300 to slide in the chute 220, the gentle path ensures stable contact between the two, completing the initial kinetic energy transfer. After entering the second slot 600, the large inclination angle in the opposite direction causes the energy storage tube 300 to instantly change its sliding direction and rise rapidly, creating a sharply expanded spatial difference with the trolley traveling in the original direction. The trolley only needs to briefly touch and push, and the energy storage tube 300 can quickly leave the contact range of the trolley under the steep rise of the second slot 600, avoiding excessive energy storage or structural collision caused by continuous pushing of the trolley.

[0028] Specifically, the slide rail balance counterweight device also includes a guide tensioning member 700 disposed below the guide pulley 230 and an auxiliary tensioning member 800 disposed below the auxiliary pulley 500; The guide tensioning member 700 abuts against the lower surface of the rope wound around the guide pulley 230; the auxiliary tensioning member 800 abuts against the lower surface of the rope wound around the auxiliary pulley 500. The guide tensioning member 700 and the auxiliary tensioning member 800 are respectively set for the guide pulley 230 and the auxiliary pulley 500, and both abut against the lower surface of the rope at the corresponding pulley, forming a "point-to-point" tension control structure: the guide tensioning member 700 can eliminate the slack of the rope at the guide pulley 230 caused by long-term use or force fluctuations in real time, avoid the rope slipping on the guide pulley 230, and ensure the stable power transmission efficiency between the counterweight 400 and the energy storage tube 300; similarly, the auxiliary tensioning member 800 can ensure the tension of the rope at the auxiliary pulley 500, prevent the transmission between the counterweight 400 and the balancing workpiece from being interrupted due to the slack of the rope, and thus avoid the failure of the load balance of the balancing workpiece.

[0029] In this embodiment, the guide tensioning component 700 includes a guide tensioning wheel and a guide adjustment structure. The guide tensioning wheel is installed below the guide pulley 230 via the guide adjustment structure, which can adjust the relative position of the guide tensioning wheel and the guide pulley 230. By having the wheel body of the guide tensioning wheel abut against the lower surface of the pull rope, traditional sliding friction is converted into rolling friction, significantly reducing wear between the tensioning component and the pull rope and extending the service life of the pull rope. The guide adjustment structure installs the guide tensioning wheel below the guide pulley 230, allowing operators to adjust the relative position of the guide tensioning wheel and the guide pulley 230. When the pull rope is slack, the tensioning wheel is adjusted upwards to increase the contact force and restore tension; when the pull rope tension is too high, it is adjusted in the opposite direction to release some tension, preventing the pull rope from becoming overly taut and breaking. This adjustable design can adapt to the natural elongation of the pull rope after long-term use, eliminating the need for frequent pull rope replacements and reducing maintenance costs. At the same time, the stable connection of the guide adjustment structure ensures that the tensioning wheel will not shift due to vibration or external force during operation, guaranteeing a continuous and reliable tensioning effect.

[0030] Furthermore, the auxiliary tensioning component 800 includes an auxiliary tensioning wheel and an auxiliary adjustment structure. The auxiliary tensioning wheel is installed below the auxiliary pulley 500 via the auxiliary adjustment structure, which can adjust the relative position of the auxiliary tensioning wheel and the auxiliary pulley 500. The wheel body of the auxiliary tensioning wheel abuts against the lower surface of the pull rope at the auxiliary pulley 500, reducing pull rope wear through rolling friction. The wheel body size can be adapted to the diameter and force of the pull rope at the auxiliary pulley 500, ensuring balanced force on the pull rope during tensioning. The auxiliary adjustment structure can independently adjust the relative position of the auxiliary tensioning wheel and the auxiliary pulley 500. When changes in the weight of the balancing workpiece cause fluctuations in pull rope tension, the operator can adjust the position of the auxiliary tensioning wheel alone to restore appropriate tension without needing to adjust other components, improving the flexibility of device maintenance. In addition, the abutment of the auxiliary tensioning wheel optimizes the fit of the pull rope within the groove of the auxiliary pulley 500, reducing the risk of pull rope disengagement and further ensuring stable transmission between the counterweight 400 and the balancing workpiece.

[0031] Preferably, the slide rail balancing counterweight device also includes a locking mechanism 900. The locking mechanism 900 is installed beside the movement path of the counterweight 400 and can abut or separate from the counterweight 400. The locking mechanism 900, installed beside the movement path of the counterweight 400, achieves precise control of the counterweight 400 through a "butt-separation" action: when the device is paused or requires maintenance, the locking mechanism 900 abuts against the counterweight 400, restricting its lifting and lowering movement, and then fixing the position of the energy storage tube 300 by a pull rope, preventing the energy storage tube 300 from sliding due to gravity or external forces, thus avoiding safety accidents or equipment failures; when the device needs to resume operation, the locking mechanism 900 separates from the counterweight 400, releasing the restriction on the counterweight 400, ensuring that the counterweight 400 can lift and lower normally without affecting the original transmission logic of the device. This design provides the device with flexible start-stop control, making it particularly suitable for intermittent operation scenarios. It avoids the need to readjust the positions of components every time the device is started or stopped, thus improving operational efficiency. Furthermore, in the event of accidental slack in the pull rope, the locking mechanism 900 can prevent the counterweight 400 from falling rapidly, further reducing safety hazards. In this embodiment, the locking mechanism 900 includes a pedal 910, an elastic element 920, and a locking element 930. The locking element 930 is rotatably mounted on the frame of the slide rail balance counterweight device via a hinge structure, and the locking element 930 can abut against the outer periphery of the counterweight 400. One end of the elastic element 920 is connected to the locking element 930 in a transmission manner, and the pedal 910 is connected to the other end of the elastic element 920 via a pull rope wound around a pulley disposed in the locking mechanism. The locking mechanism 900's "pedal 910 - elastic element 920 - locking element 930" structure achieves convenient and reliable locking and releasing through mechanical cooperation: when the counterweight 400 rises to a predetermined height, it can lock and abut against the locking element 930. The locking element 930 is rotatably mounted on the frame through a hinge structure. The rotation design allows the locking element 930 to flexibly abut or separate from the outer periphery of the counterweight 400, and the surface contact abutment method can avoid local wear caused by point contact, extending the service life of the locking element 930 and the counterweight 400. One end of the elastic element 920 is connected to the locking element 930, providing a continuous preload to ensure that the locking element 930 remains in contact with and locked to the counterweight 400 in the non-drive state. This locking state can be maintained without additional power supply, reducing equipment energy consumption. Simultaneously, the preload of the elastic element 920 can be adjusted according to the weight of the counterweight 400, ensuring reliable locking without excessively compressing the counterweight 400. The pedal 910 is connected to the other end of the elastic element 920 via a pull rope wound around a pulley. The operator only needs to step down on the pedal 910 to pull the elastic element 920, causing it to deform and rotate the locking element 930 around the hinge, separating it from the counterweight 400. This operation is convenient and effortless. The pulley design changes the direction of force on the pull rope, allowing the pedal 910 to be installed in an easily accessible position. The operator can control the locking state without approaching the counterweight 400, significantly improving operational safety.

[0032] The above description is only a preferred embodiment of the present utility model and does not limit the patent scope of the present utility model. All equivalent structural transformations made under the inventive concept of the present utility model using the contents of the present utility model specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present utility model.

Claims

1. A slide rail balancing counterweight device, characterized in that, This includes conveyor tracks, guide components, energy storage pipes, and counterweights; The guiding component includes two symmetrically spaced guide rails. The guide rails are provided with grooves along the length of the conveying track for the energy storage tube to be inserted and slid. Both ends of the energy storage tube are respectively embedded in the grooves of the two guide rails. A guide pulley is provided below the guide member, and the counterweight is located below the guide pulley. The chute includes a sliding start end and a sliding end end for the energy storage tube to slide, and the guide pulley includes a plurality of guide wheels spaced apart, the guide wheels being spaced apart from below the sliding start end; The energy storage pipe is equipped with directional pulleys at both ends, and the directional pulleys are connected to the counterweight via a pull rope wound around the guide pulley.

2. The slide rail balancing counterweight device as described in claim 1, characterized in that, The slide rail balancing counterweight device is also equipped with an auxiliary pulley, which is located below the guide member and close to the sliding end; The counterweight is connected to the balancing workpiece by a rope wound around the auxiliary pulley.

3. The slide rail balancing counterweight device as described in claim 2, characterized in that, The counterweight is located below the auxiliary pulley, and the auxiliary pulley is spaced apart along the sliding end.

4. The slide rail balancing counterweight device as described in claim 1, characterized in that, The slide groove is inclined upwards from the beginning of the sliding end toward the end of the sliding end.

5. The slide rail balancing counterweight device as described in claim 4, characterized in that, The guide rail also includes a second groove, which communicates with the slide groove. The energy storage tube can slide within the second groove. The second groove extends upward in a direction away from the sliding start end, and the inclination angle of the second groove is greater than the inclination angle of the slide groove.

6. The slide rail balancing counterweight device as described in claim 2, characterized in that, The slide rail balancing counterweight device also includes a guide tensioning member disposed below the guide pulley and an auxiliary tensioning member disposed below the auxiliary pulley; The guide tensioning member abuts against the lower surface of the pull rope wrapped around the guide pulley; the auxiliary tensioning member abuts against the lower surface of the pull rope wrapped around the auxiliary pulley.

7. The slide rail balancing counterweight device as described in claim 6, characterized in that, The guide tensioning component includes a guide tensioning wheel and a guide adjustment structure. The guide tensioning wheel is mounted below the guide pulley via the guide adjustment structure, and the guide adjustment structure can adjust the relative position of the guide tensioning wheel and the guide pulley.

8. The slide rail balancing counterweight device as described in claim 6, characterized in that, The auxiliary tensioning component includes an auxiliary tensioning wheel and an auxiliary adjustment structure. The auxiliary tensioning wheel is mounted below the auxiliary pulley via the auxiliary adjustment structure, and the auxiliary adjustment structure can adjust the relative position of the auxiliary tensioning wheel and the auxiliary pulley.

9. The slide rail balancing counterweight device as described in claim 1, characterized in that, The slide rail balancing counterweight device also includes a locking mechanism, which is installed beside the movement path of the counterweight and can abut against or separate from the counterweight.

10. The slide rail balancing counterweight device as described in claim 9, characterized in that, The locking mechanism includes a pedal, an elastic element, and a locking element; the locking element is rotatably mounted on the frame of the slide rail counterweight device via a hinge structure, and the locking element can abut against the outer periphery of the counterweight; one end of the elastic element is drivenly connected to the locking element, and the pedal is drivenly connected to the other end of the elastic element via a pulley arranged in the locking mechanism via a pull rope.

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