AU2020103577A4 - Spindle limiting device - Google Patents

Abstract

The invention discloses a spindle limiting device , the invention belongs to the technical field of low-voltage apparatus component equipment. A spindle limiting device, including a 5 moving contact assembly , a fixed contact assembly and a spindle, wherein further including a limiting plate and a cantilever fixedly arranged on the spindle, wherein the limiting plate freely rotates by taking a rotating shaft as the axis, the limiting plate is provided with a first pressing-against portion and a second pressing-against portion, and a second protrusion matched with the second pressing-against portion is disposed at the lower end of the cantilever and a first 0 protrusion is disposed at the upper end of the cantilever .The invention is simple in structure, includes a small number of parts, and occupies a small space. The spindle limiting device is implemented by utilizing the structure of the limiting plate and the gravity principle, impact resistance of the limiting plate is improved, and rebound of the spindle is effectively stopped, so that a short-time withstand index of a frame-type circuit breaker is improved. 5 212 1 413 Fig. 1 1/6

Description

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Fig. 1

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SPINDLE LIMITING DEVICE

Field

[0001] The invention belongs to the technical field of low-voltage apparatus component equipment, and particularly relates to a spindle limiting device of a low-voltage circuit breaker.

Background

[0002] Currently, a short-time withstand index of a frame-type circuit breaker is continuously increased, in a case that a size of the circuit breaker is unchanged, increasing a contact pressure is a relatively direct method. However, the method brings in the side effect that when a moving contact is opened, a force for a mechanism cantilever to impact a limiting shaft is increased so as to intensify contact rebound and reduce a spacing. In the breaking test, reduction of the spacing is very liable to cause arc restriking, resulting in a breaking fault.

[0003] Currently, in the market, spindle limitation is implemented by utilizing an inertia principle, which has a certain requirement for a rotating speed of a mechanism spindle in the opening process and is poor in reliability. In addition, after being repeatedly impacted, a limiting plate which plays a vital role in the limiting process is liable to generate fault phenomena that the limiting plate is oblique and inflexible in rotation, a rotating shaft of the limiting plate is deformed, a torsion spring is blocked and jammed and the like.

[0004] Patent Application No.201710149068.X discloses a circuit breaker moving contact anti-rebound device, including a circuit breaker body, a mechanism spindle arranged on the circuit breaker body and an anti-rebound mechanism. A second limiting shaft is arranged below a fixed shaft, a rotating plate includes a struck portion, a blocking portion and a mounting hole; a cross section shape of an outer contour surface of the blocking portion is set to be of an !5 arc-shaped structure, and a distance between an arc-shaped contour structure and the circle center of the mounting hole from the lower end to the upper end is gradually reduced; the rotating plate is rotationally mounted on the fixed shaft by the mounting hole; a torsion spring sleeves the fixed shaft; and two torsion arms of the torsion spring respectively act on the second limiting shaft and the rotating plate. However, the anti-rebound device is complex, needs a plurality of parts to be combined for working, and is poor in anti-rebound effect, resulting in influence on a limiting effect.

[0005] According to a circuit breaker with the application number of No.98122539.X, which is provided with an automatic grapple and can prevent a tripping-off contact arm from being rebounded, a device 101 at an upright position is positioned by a latch hook 89, two jaws 93 are aligned so as to be jointed with a stopping part 75, when the contact arm 27 reaches a tripping-off position, the latch hook 89 rotates to a latch position from the upright position, and meanwhile, the jaws 93 are jointed with the stopping part 75 so as to prevent the contact arm 27 from being rebounded from the tripping-off position. In an embodiment of the circuit breaker, the device 101 at the upright position is a torsion spring 101. Refer to contents on Line 3 in Page 6/6 in the description that: as shown in Fig. 4, one torsion spring 101 jointed with the top of the contact arm 27 and a protrusion 99 on the latch hook enables the latch hook to be reset to one upright position in the aspect of angle, and at this position, two jaws 93 are aligned so as to be jointed with the stopping part 75. Therefore, although this patent achieves the technical effect of stopping a spindle from being rebounded, movement of a limiting plate of the circuit breaker needs to be implemented by the torsion spring, and the device is complex and poor in anti-rebound effect, resulting in influence on the limiting effect.

[0006] According to a driving chain of a movable contact of a power circuit breaker with the application number of No.018019403.6, a braking part (32a; 32b; 42) is attached to a locking part (13; 31), the locking part is guided on the braking part in the opening process, and before reaching a preset position of a connecting piece 3, the locking part is kept at a position where the locking part is static relative to the connecting piece. Refer to contents on Line 25 in Page 4/6 in the description that: the locking part is supported on a pin 20 passing through the connecting piece by a stopping face 19 under the action of a force of a resetting spring 18; refer to contents on Line 25 in Page 5/6 in the description that: according to Fig. 5 to Fig. 7, the braking part attached to the locking part 31 is designed as a hairpin-shaped butterfly spring, and a spring coil of the hairpin-shaped butterfly spring winds a first coupling pin 33; and refer to contents on Line 10 in Page 6/6 in the description that: according to Fig. 8 to Fig. 10, the braking part in another embodiment is designed as a rigid part 42 with a nail guide channel 41, and the part is fixed on a coupling joint 5 of the driving chain. Therefore, although this patent !5 achieves the technical effect of stopping a spindle from being rebounded, movement of a limiting plate of the power circuit breaker needs to be implemented by the butterfly spring, and the device is complex and poor in anti-rebound effect, resulting in influence on the limiting effect.

[0007] Any references to prior art should not be taken as admissions of common general knowledge in the field.

Summary

[0008] The invention aims to provide a spindle limiting device which is simple, convenient and stable to work.

[0009] Specifically, the invention is implemented by adopting the following technical solutions:

[0010] A spindle limiting device, including a moving contact assembly , a fixed contact assembly and a spindle, wherein further including a limiting plate and a cantilever fixedly arranged on the spindle, wherein the limiting plate freely rotates by taking a rotating shaft as the axis, the limiting plate is provided with a first pressing-against portion and a second pressing-against portion, and a second protrusion matched with the groove is disposed at the lower end of the cantilever and a first protrusion is disposed at the upper end of the cantilever

.

[0011] When an opening and closing structure moves from a closed state to an open state, the first protrusion collides with the first pressing-against portion, under the pushing action of the first pressing-against portion on the second pressing-against portion, the second pressing-against portion holds the second protrusion of the cantilever , and rebound of the spindle is stopped.

[0012] It should be understood that the cantilever on the spindle is fixed to the spindle, and rotates along rotation of the spindle.

[0013] Wherein the second pressing-against portion is of a hook shape with a groove.

[0014] Wherein the rotating shaft is a riveting shaft.

[0015] Wherein the spindle is provided with a baffle , the spindle limiting device further includes a limiting shaft matched with the baffle , in the opening process, the lower end of the baffle is blocked by the limiting shaft so as to finally limit the position of the spindle .

[0016] It should be understood that in the opening process, the lower end of the baffle is blocked by the limiting shaft, so that the spindle is fixed at one position in the opening process.

[0017] The spindle limiting device as recited in claim 1, wherein further including a supporting plate , wherein one end of the supporting plate sleeves the limiting shaft , while the other end of the supporting plate sleeves the rotating shaft. !5 [0018] It should be understood that arrangement of the supporting plate improves structural strength, and meanwhile, takes a protective effect.

[0019] The spindle limiting device as recited in claim 6, wherein both ends of the supporting plate are fixed by split washers.

[0020] The invention has the following advantageous effects that the spindle limiting device disclosed by the invention is simple in structure, includes a small number of parts, and occupies a small space. The spindle limiting device is implemented by utilizing the structure of the limiting plate and the gravity principle, impact resistance of the limiting plate is improved, and rebound of the spindle is effectively stopped, so that a short-time withstand index of a frame-type circuit breaker is improved.

Brief Description of the Drawings

[0021] Fig. 1 is an overall structural schematic diagram of the spindle limiting device of the invention.

[0022] Fig. 2 is a side view of the spindle limiting device of the invention.

[0023] Fig. 3 is a schematic diagram of the spindle limiting device in a closed working state according to the invention.

[0024] Fig. 4 is a schematic diagram of the spindle limiting device in an open working state according to the invention.

[0025] Fig. 5 is an enlarged view in which a cantilever collides with the upper end of a limiting plate according to the invention.

[0026] Fig. 6 is an enlarged view in which the cantilever collides with the lower end of the limiting plate according to the invention.

[0027] Reference signs in the drawings are: 1-moving contact assembly, 2-fixed contact assembly, 3-spindle, 4-side plate, 5-limiting plate, 6-connecting rod, 7-cantilever, 8-baffle, 9-riveting shaft, 10-first pressing-against portion, 11-second pressing-against portion, 12-limiting shaft, 13-supporting plate, 14-first protrusion, and 15-second protrusion.

Detailed Description of the Embodiments

[0028] The invention will be further described in detail below in combination of embodiments with reference to the drawings.

[0029] Embodiment 1:

[0030] A spindle limiting device in this embodiment is applied to an opening and closing !5 structure as shown in Fig. 1. The opening and closing structure includes a fixed contact assembly 2, a moving contact assembly 1 and a spindle 3. The spindle 3 is supported and positioned by two side plates 4, and the spindle 3 can rotate. The spindle 3 isfixedly provided with a connecting rod 6, and the connecting rod 6 is hinged with the moving contact assembly 1, so that the moving contact assembly 1 is linked along with forward and reverse rotation of the spindle 3, thereby implementing contact or separation between a moving contact in the moving contact assembly 1 and a fixed contact in thefixed contact assembly 2, i.e., implementing opening and closing actions. The opening and closing structure implements a closed state and an open state between the fixed contact assembly 2 and the moving contact assembly 1, respectively as shown in Fig. 3 and Fig. 4. It should be noted that the spindle limiting device disclosed by the invention is not limited to application to the opening and closing structure as shown in Fig. 1, and can also be applied to any other places where the same function needs to be achieved, and structures of the fixed contact assembly and the moving contact assembly in the spindle limiting device can also be in any other forms without influence on function achieving of the invention.

[0031] The spindle limiting device in this embodiment includes a cantilever 7 fixedly arranged on the spindle 3 and a limiting plate 5 matched with the cantilever 7 to achieve a function of preventing the spindle 3 from rebounding, and the specific structure is as shown in Figs. 1, 5 and 6. The limiting plate 5 can freely rotate by taking a rotating shaft as the axis. According to this embodiment, a first pressing-against portion 10 is disposed at the upper end of the limiting plate 5, a second pressing-against portion 11 is disposed at the lower end of the limiting plate 5, the second pressing-against portion 11is of a hook shape with a groove, and in a mode of being matched with the groove, a second protrusion 15 matched with the groove is disposed at the lower end of the cantilever 7 and a first protrusion 14 is disposed at the upper end of the cantilever 7. When the opening and closing structure moves from a closed state to an open state, the spindle 3 rotates to drive the cantilever 7 to be linked, the first protrusion 14 of the cantilever 7 collides with the first pressing-against portion 10 at the upper end of the limiting plate 5, and under the pushing action of the first pressing-against portion 10 on the second pressing-against portion 11, rotation of the cantilever 7 and the limiting plate 5 towards opposite expected directions is implemented, so that the second protrusion 15 of the cantilever 7 gradually moves into the groove from a state in which the second protrusion 15 is separated from the groove of the limiting plate 5, a hook portion of the second pressing-against portion 11 of the limiting plate 5 holds the cantilever 7, and rebound of the spindle 3 is stopped. The hook portion of the second pressing-against portion 11 of the limiting plate 5 only holds the cantilever 7 for short time, due to existence of gravity, the hook portion at the lower end of the limiting plate 5 is restored to a position below the rotating shaft as shown in Fig. 5, and the limiting plate 5 returns to an initial state and waits for the opening and closing structure to move from the closed state to the open state next time.

[0032] It should be noted that this embodiment has no special limitation to an arrangement mode of the rotating shaft on the limiting plate 5, the arrangement mode not only can be that the rotating shaft is fixed to the side plates and the limiting plate 5 matched with the rotating shaft movably sleeves the rotating shaft, but also can be that the rotating shaft is positioned and supported only by the side plates and can rotate per se and the limiting plate 5 matched with the rotating shaft is fixed to the rotating shaft. In this embodiment, the arrangement mode in which the rotating shaft is fixed to the side plates is preferably adopted, and further, preferably, a riveting mode, i.e., the riveting shaft 9 as shown in Figs. 5 and 6, is adopted for fixing. The limiting plate 5 is provided with a hole, and the limiting plate 5 sleeves the riveting shaft 9 through the hole and can flexibly rotate.

[0033] In order to determine a final position of the spindle in the open state, in this embodiment, a baffle 8 and a limiting shaft 12 matched with the baffle 8, as shown in Fig. 2, are also arranged. In the opening process, after the cantilever 7 is held by the hook portion of the limiting plate 5, the cantilever 7 slowly rotates along with the spindle until the lower end of the baffle 8 fixed to the spindle is blocked by the limiting shaft 12, so as to stop the spindle from further rotating, thereby finally limiting the position of the spindle 3. The objective above can be achieved by fixing one end of the limiting shaft 12 to the side plate 4, but as a preferred structure, in this embodiment, one end of the limiting shaft 12 is fixed to one side plate 4, while the other end is fixed to the other side plate 4, so that both left and right side plates 4 are connected by the limiting shaft 12.

[0034] In order to further improve the structural strength, in this embodiment, a supporting plate 13 as shown in Figs. 1, 3 and 4 is also arranged. The limiting shaft 12 provides support for the supporting plate 13, one end of the supporting plate 13 sleeves the limiting shaft 12, the other end of the supporting plate 13 sleeves the riveting shaft 9, and both ends of the supporting plate 13 are fixed by split washers. Due to a very large stress of the limiting plate in the working process, it is very liable to cause bending of the riveting shaft 9. By the supporting plate 13, both ends of the riveting shaft 9 are fixed through the side plates 4 and the supporting plate 13, so that stability is reinforced; and meanwhile, the supporting plate 13 takes a protective effect, so that the limiting plate 5 is positioned in a relatively closed region, thereby avoiding influence of the limiting plate 5 on other parts in the rotating process.

[0035] The movement principle of the invention is that:

[0036] SI: as shown in Fig. 5, when the rotating shaft rapidly rotates to an opening position !5 from a closing position, the upper end of the cantilever 7 impacts a first impact point at the upper end of the limiting plate 12; and

[0037] S2: as shown in Fig. 6, the limiting plate rotates to a position as shown in the drawing, simultaneously, the spindle starts to rebound, the lower end of the cantilever 7 impacts a second impact point at the lower end of the limiting plate 12, the lower end of the limiting plate 12 holds the cantilever 7, and rebound of the spindle 3 is stopped.

[0038] Although the invention has been disclosed with the preferred embodiments as above, the embodiments are not used for limiting the invention. Any equivalent changes or modifications without departure from the spirit and the scope of the invention shall fall within the scope of the invention. Therefore, the protection scope of the invention should take contents defined by the claims of this application as the standard.

Claims (7)

1. A spindle limiting device, including a moving contact assembly, a fixed contact assembly and a spindle, wherein further including a limiting plate and a cantilever fixedly arranged on the spindle, wherein the limiting plate freely rotates by taking a rotating shaft as the axis, the limiting plate is provided with a first pressing-against portion and a second pressing-against portion, and a second protrusion matched with the second pressing-against portion is disposed at the lower end of the cantilever and a first protrusion is disposed at the upper end of the cantilever.

2. The spindle limiting device as recited in claim 1, wherein when an opening and closing structure moves from a closed state to an open state, the first protrusion collides with the first pressing-against portion, under the pushing action of the first pressing-against portion on the second pressing-against portion, the second pressing-against portion holds the second protrusion of the cantilever , and rebound of the spindle is stopped.

3. The spindle limiting device as recited in claim 1, wherein the second pressing-against portion is of a hook shape with a groove.

4. The spindle limiting device according to claim 1, wherein the rotating shaft is a riveting shaft.

5. The spindle limiting device as recited in claim 1, wherein the spindle is provided with a baffle , the spindle limiting device further includes a limiting shaft matched with the baffle , in the opening process, the lower end of the baffle is blocked by the limiting shaft so as to finally limit the position of the spindle .

6. The spindle limiting device as recited in claim 1, wherein further including a supporting plate , wherein one end of the supporting plate sleeves the limiting shaft, while the other end of the supporting plate sleeves the rotating shaft.

!5

7. The spindle limiting device as recited in claim 6, wherein both ends of the supporting plate are fixed by split washers.