Spring stretching device

Abstract

The utility model relates to the field of equipment suitable for assembly of deformed articles, in particular to a spring stretching device. The spring stretching device is used for solving the problem that in the prior art, a stretching mode of an unpowered spring is low in stretching efficiency. The spring stretching device comprises a supporting seat, a nut is rotationally assembled on the supporting seat, a cantilever type output rod is installed in the nut, the output rod can axially reciprocate along with forward and reverse rotation of the nut, a hanging structure capable of being connected with a metal hanging plate of a spring in a hanging mode is arranged on the output rod, and the nut is provided with a driving mechanism. The driving mechanism comprises an operation shaft, and a speed increasing transmission mechanism is arranged between the operation shaft and the nut. The matching efficiency of the output rod and the nut is improved through the speed-increasing transmission mechanism, compared with the prior art, the spring stretching efficiency is improved, and the spring is easier and more convenient to install.

Description

Technical Field

[0001] The utility model relates to the field of equipment applicable to the assembly of deformed articles, and particularly relates to a spring stretching device. Background Art

[0002] Post switches are widely used in important nodes of overhead networks. As important sectionalizing, connecting, demarcating, and branching nodes of the main trunk line of the distribution network, they play the roles of monitoring the operation of the distribution network line and quickly judging, positioning, isolating, and restoring faulty lines, and are indispensable products in the distribution network.

[0003] A connecting rod and a spring are arranged inside the post switch. When the connecting rod moves, the opening and closing of the post switch can be realized. One end of the spring is fixed on the box body, and the other end is hung on the connecting rod pin of the connecting rod through a metal hanging plate thereon. When the spring is in a stretched state, its elastic potential energy can ensure the quick movement of the connecting rod to realize opening. Specifically, the spring is located inside the post switch and one end of it is fixed. Therefore, for the spring inside the post switch, the manual installation method is usually adopted. The staff needs to hook one end of the spring with a hook, stretch it to a specified length and then hang the metal hanging plate at the end of the spring on the connecting rod pin. This installation method is laborious and inefficient.

[0004] The existing spring stretching devices mainly include two types: powered and non-powered. Among them, the powered type includes pneumatic and electric forms, which have the advantages of stable operation, controllable and adjustable pulling force, and fast stretching. However, when in use, an electric cylinder or a cylinder needs to be used as a power source, and the manufacturing, maintenance, and maintenance costs are relatively high. The mechanical device has a simple structure, easy maintenance, and safe and reliable use, but it needs to manually rotate the screw rod to lift and lower, and the installation efficiency is still low, which is not suitable for the fast-paced assembly places on the production line.

[0005] At the same time, due to the installation environment of the spring inside the post switch being assembly on the production line and one end of the spring being fixed, the existing spring stretching devices are restricted by space and it is difficult to realize the spring stretching in this case. Summary of the Utility Model

[0006] The purpose of the utility model is to provide a spring stretching device to solve the problem of low stretching efficiency of the existing non-powered spring stretching method.

[0007] To solve the above technical problems, the spring stretching device of the utility model adopts the following technical solutions:

[0008] A spring stretching device includes a support base, on which a nut is rotatably assembled. An output rod in a cantilever form is installed in the nut. The output rod can axially reciprocate as the nut rotates forward and backward. A hanging structure capable of being hooked to a metal hanging plate of a spring is arranged on the output rod. The nut is configured with a driving mechanism, and the driving mechanism includes an operating shaft. A speed increasing transmission mechanism is arranged between the operating shaft and the nut.

[0009] The present utility model proposes a brand-new technical solution, which uses a speed increasing mechanism to improve the matching efficiency between the output rod and the nut, making the linear motion of the output rod more rapid, thereby driving the spring hooked to the output rod to be stretched efficiently. In this way, compared with the prior art, the efficiency of spring stretching is improved, and the installation of the spring is made more convenient.

[0010] Further, the speed increasing transmission mechanism is a gear transmission mechanism.

[0011] Further, the gear transmission mechanism includes a first bevel gear and a second bevel gear that mesh with each other. The diameter of the first bevel gear is larger than that of the second bevel gear. The operating shaft transmits the motion to the first bevel gear, and the rotation of the second bevel gear drives the nut to rotate so that the output rod moves linearly.

[0012] Further, the operating shaft is perpendicular to the output rod.

[0013] Further, a central hole is provided in the center of the second bevel gear, and the nut is arranged in the central hole of the second bevel gear, and the two are synchronously rotated through a connecting key.

[0014] Further, the thread of the output rod is a trapezoidal thread.

[0015] Further, a rotary input structure is arranged on the operating shaft.

[0016] Further, the rotary input structure is a hand wheel.

[0017] Further, the hanging structure is a retaining pin arranged on the output rod.

[0018] Further, the support base is a gear box. Description of the Drawings

[0019] Figure 1 is a schematic structural diagram of a spring stretching device of the present utility model;

[0020] Figure 2 is Figure 1 a top view of;

[0021] Figure 3 is Figure 2 a cross-sectional view taken at A-A;

[0022] Figure 4 Schematic structural diagram of placing a spring stretching device above the box body of the connecting rod of a pole-mounted switch and using the spring stretching device to pull the spring to a position corresponding to the axis of the connecting rod pin;

[0023] Figure 5 is Figure 4 Partial enlarged schematic diagram at position B.

[0024] In the figure: 1. Sealed gearbox; 2. First bevel gear; 3. Output rod; 4. Second bevel gear bushing; 5. Second bevel gear; 6. Nut; 7. Stop pin; 8. First bevel gear bushing; 9. Operating shaft; 10. Rocking handle; 11. Rocking wheel; 12. Connecting rod; 13. Connecting rod pin; 14. Spring. Specific implementation mode

[0025] One end of the spring in the pole-mounted switch is fixed on the box body, and it is difficult for the existing spring stretching device to stretch the spring under such conditions. Therefore, the spring in the pole-mounted switch is usually installed manually. The staff needs to hook one end of the spring with a hook, stretch it to a specified length and then hang the metal hanging plate at the end of the spring on the connecting rod pin. This installation method is laborious and inefficient. And the existing mechanical spring stretching device needs to manually rotate the screw rod to lift and lower, and the installation efficiency is still low, which is not suitable for the fast-paced assembly places on the production line.

[0026] The present utility model proposes a brand-new technical solution for the problems existing in the above technical solutions. The core idea of the present utility model is: using a speed increasing mechanism to improve the matching efficiency between the output rod and the nut, making the linear movement of the output rod faster, so as to drive the spring connected to the output rod to be stretched efficiently. In this way, compared with the prior art, the efficiency of spring stretching is improved, and the installation of the spring is more convenient.

[0027] Based on the above inventive concept, the basic scheme of a spring stretching device of the present utility model is as follows:

[0028] The spring stretching device includes a support seat, and the support seat can provide a stable support for the components in the spring stretching device. A nut 6 is rotatably assembled on the support seat, and a cantilever-type output rod 3 is installed in the nut 6. The output rod 3 in this embodiment is a screw rod. The output rod 3, that is, the screw rod, can axially reciprocate with the forward and reverse rotation of the nut. The cantilever end of the output rod 3 enables the spring stretching device to work even when one end of the spring 14 is fixed. A hanging structure that can be hooked with the metal hanging plate of the spring 14 is provided on the output rod 3. The nut 6 is provided with a driving mechanism, and the driving mechanism includes an operating shaft 9. A speed increasing transmission mechanism is provided between the operating shaft 9 and the nut. When in use, such as Figure 4 , Figure 5As shown, the support base can be placed on the upper part of the box body of the connecting rod 12 of the pole-mounted switch, and the extending direction of the axis of the output rod 3 can pass through the position corresponding to the axis of the connecting rod pin 13. Hang the spring hanging plate of the spring 14 on the hanging structure on the output rod 3, and transmit the motion to the speed-increasing transmission mechanism through the operating shaft 9. The nut 6 at the output end of the speed-increasing transmission mechanism rotates to drive the output rod 3 to move linearly, so as to stretch the metal hanging plate hung on the output rod 3 to the position corresponding to the axis of the connecting rod pin 13, making the installation of the spring 14 more labor-saving and simpler and more convenient.

[0029] In this embodiment, the speed-increasing transmission mechanism is a gear transmission mechanism. A bevel gear transmission mechanism is used in this embodiment. The bevel gear transmission mechanism has a compact structure, can make better use of the surrounding space, and reduces the overall volume of the device. In addition, in other embodiments, the speed-increasing transmission mechanism can be a spur gear transmission mechanism. Of course, in other embodiments, the speed-increasing transmission mechanism can also be a belt transmission mechanism or a chain transmission mechanism.

[0030] In this embodiment, the bevel gear transmission mechanism includes Figure 3 the mutually meshing first bevel gear 2 and second bevel gear 5 as shown. The diameter of the first bevel gear 2 is larger than that of the second bevel gear 5. The operating shaft 9 transmits the rotational motion to the first bevel gear 2, and the second bevel gear 5 meshing with the first bevel gear 2 also rotates accordingly, thereby driving the nut 6 to rotate to make the output rod 3 move linearly. At this time, the number of teeth of the first bevel gear 2 is also larger than that of the second bevel gear 5. When the first bevel gear 2 rotates one circle, the number of rotation circles of the second bevel gear 5 is more than one circle, thus fulfilling the speed-increasing requirement of the bevel gear transmission mechanism. The speed-increasing transmission mechanism composed of two bevel gears has a simple structure and is easy to install.

[0031] In this embodiment, the operating shaft 9 is perpendicularly arranged to the output rod. Two mutually perpendicular and meshing straight bevel gears are used in this embodiment. Thus, the operating shaft 9 and the output rod are also perpendicularly arranged. Such an arrangement makes the input end and the output end of the speed-increasing transmission mechanism not in the same plane, avoiding interference between the input operation and the linear motion of the output rod. In addition, in other embodiments, to meet the requirements of different operation planes of the operating shaft, two mutually meshing skew bevel gears can be used, and the angle between the two skew bevel gears can be less than or greater than 90 degrees. Thus, the angle between the operating shaft and the output rod can also be less than or greater than 90 degrees.

[0032] In this embodiment, a central hole is provided in the center of the second bevel gear 5, and the nut 6 is arranged in the central hole of the second bevel gear 5. The two achieve synchronous rotation through a connecting key. In this embodiment, the second bevel gear 5 and the nut 6 achieve synchronous rotation through a flat key. Key grooves are provided at corresponding positions of the nut 6 and the central hole of the second bevel gear 5. The flat key is placed in the key groove, and the synchronous rotation between the nut 6 and the second bevel gear 5 is achieved by the extrusion of the flat key against the side surface of the key groove. The flat key has a simple structure, is convenient for installation and disassembly, and can ensure the reliability of the synchronous rotation of the nut 6 and the second bevel gear 5. In addition, in other embodiments, external splines can be provided on the outer circumference of the nut, and internal splines that can cooperate with the external splines of the nut can be provided on the central hole of the second bevel gear, and synchronous transmission between the two is achieved through the splines. Of course, in other embodiments, the nut and the second bevel gear can also achieve synchronous rotation by means of bonding or welding.

[0033] In this embodiment, the thread of the output rod 3 is a trapezoidal thread. The thread of the nut 6 is also a trapezoidal thread. When the trapezoidal threads are engaged, they are in close contact with the tapered surface and are not easily loosened, having good self-locking performance. In this way, the output rod 3 can be kept in a certain position to facilitate the connection of the spring 14 and the connecting rod pin 13. In addition, in other embodiments, to ensure the transmission efficiency, the threads of the output rod and the output rod nut can also be rectangular threads.

[0034] In this embodiment, a rotational input structure is provided on the operating shaft 9. If the operating shaft is directly rotated, the operation is difficult and laborious. Therefore, a rotational input structure is provided in this embodiment, which can facilitate the rotational operation of the operating shaft 9.

[0035] In this embodiment, the rotational input structure is a Figure 2 rocking wheel 11 as shown. The diameter of the rocking wheel 11 in this embodiment is larger than the diameter of the first bevel gear 2, and a rocking handle 10 is provided at the edge of the rocking wheel 11. In this way, the distance from the rocking handle 10 to the operating shaft 9 is increased, and a larger torque will be generated compared to the rocking handle 10 located in the middle of the rocking wheel 11 when the same amount of force is applied. Therefore, during use, the staff can use less force to generate sufficient torque to drive the driving wheel to rotate, making the operation more labor-saving. In addition, in other embodiments, to meet the needs, the rocking handle 10 can also be placed on the inner circumferential surface of the rocking wheel 11. The rocking handle 10 in this embodiment is perpendicular to the rocking wheel 11. In addition, in other embodiments, the rocking handle 10 can also extend radially outward along the rocking wheel 11. Of course, in other embodiments, the torque amplification rotational input structure can also be a rotating rod, which has a horizontal rod extending radially along the operating shaft, and a holding structure is provided at the edge of the horizontal rod. In this way, the rotation can be directly transmitted to the operating shaft by rotating the rotating rod.

[0036] In this embodiment, the hanging structure is the retaining pin 7 provided on the output rod 3. A groove is provided on the retaining pin 7, and a hanging hole is provided on the metal hanging plate of the spring 14. Hanging the hanging hole at the groove of the retaining pin 7 on the output rod 3 can achieve reliable hanging of the spring 14 and the output rod 3. In addition, in other embodiments, the hanging structure can also be a hook provided on the output rod, as long as it is ensured that the spring can be reliably hung with the hanging structure.

[0037] In this embodiment, the support base is the Figure 1 gearbox 1 as shown. The gearbox 1 can stably support the speed increasing transmission mechanism inside it. In addition, in other embodiments, the support base can also be a support frame, as long as it is ensured that the first bevel gear and the second bevel gear can be supported. A first bevel gear shaft sleeve 8 and a second bevel gear shaft sleeve 4 are provided on the gearbox 1. The operating shaft 9 passes through the first bevel gear shaft sleeve 8 and is in sleeve fit with the first bevel gear shaft 8. The second bevel gear shaft sleeve 4 is rotationally assembled with the nut 6, and the output rod passes through the second bevel gear shaft sleeve and can move linearly. The gearbox 1 of this embodiment is a sealed gearbox, and the sealed gearbox 1 can effectively prevent impurities in the external environment from entering the bevel gear interior, avoiding wear, corrosion or jamming of the bevel gear, thereby extending the service life of the spring stretching device.

[0038] The above is only a preferred embodiment of the present invention and is not intended to limit the present invention. The patent protection scope of the present invention is subject to the claims. Any equivalent structural changes made by using the description and drawings of the present invention should be equally included in the protection scope of the present invention.

Claims

1. A spring tensioning device, characterized in that: It includes a support seat, on which a nut is rotatably mounted, a cantilevered output rod is installed in the nut, the output rod can move axially back and forth with the forward and reverse rotation of the nut, a hanging structure that can be hung with a metal hanging plate of a spring is arranged on the output rod, the nut is equipped with a driving mechanism, the driving mechanism includes an operating shaft, and a speed increasing transmission mechanism is arranged between the operating shaft and the nut.

2. The spring tensioning device according to claim 1, characterized in that: The speed increasing transmission mechanism is a gear transmission mechanism.

3. The spring tensioning device according to claim 2, characterized in that: The gear transmission mechanism includes a first bevel gear and a second bevel gear meshing with each other, the diameter of the first bevel gear is larger than the diameter of the second bevel gear, the operating shaft transmits motion to the first bevel gear, and the rotation of the second bevel gear drives the nut to rotate so that the output rod moves linearly.

4. The spring tensioning device according to claim 3, characterized in that: The operating shaft is arranged perpendicularly to the output rod.

5. The spring tensioning device according to claim 3, characterized in that: The center of the second bevel gear is provided with a center hole, and the nut is arranged in the center hole of the second bevel gear, and the two realize synchronous rotation through a connecting key.

6. The spring tensioning device according to any one of claims 1 to 5, characterized in that: The thread of the output rod is a trapezoidal thread.

7. The spring tensioning device according to any one of claims 1 to 5, characterized in that: A rotation input structure is arranged on the operating shaft.

8. The spring tensioning device according to claim 7, characterized in that: The rotation input structure is a rocker.

9. The spring tensioning device according to any one of claims 1 to 5, characterized in that: The hanging structure is a stop pin arranged on the output rod.

10. The spring tensioning device according to any one of claims 1 to 5, characterized in that: The supporting seat is a gear box.

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