CN1052810C - Circuit breaker - Google Patents

Abstract

A circuit breaker with improved breaking performance by suppressing arc generation, simplifying the structure and significantly reducing the number of parts. There is a first fixed conductor on the power supply side, a second fixed conductor on the load side, an intermediate fixed conductor between these two fixed conductors, and a first moving conductor and a second moving conductor that are fixed on each power supply side and load side respectively. Between the conductors and the intermediate fixed conductors, forming a series electrical path with each conductor, wherein the opening/closing mechanism opens substantially simultaneously between the first fixed conductor and the intermediate fixed conductor and between the intermediate fixed conductor and the second fixed conductor the moving conductor.

Description

breaker

The present invention relates to a circuit breaker, and more particularly to a circuit breaker adapted to prevent arcing, simplify construction, and greatly reduce the number of parts.

A typical existing circuit breaker includes a pair of static contacts and moving contacts, an arc extinguishing device, an opening/closing mechanism for rotating the moving contacts, a manual operating handle and the like. When the current flowing through the electrical channel exceeds the rated value, the tripping mechanism of the circuit breaker will start, and the opening/closing mechanism will act to separate the moving contact from the static contact, and the current will be cut off. For the connection between the end of the moving contact and the electrical channel, a bendable flexible wire woven into a mesh by metal wires is used, so that the rotation does not affect the electrical connection. The opening/closing mechanism is connected by a crank connecting rod, which transmits the movement of the tripping mechanism or the handle to the moving contact.

In addition, using electromagnetic repulsion in the current limiting structure, the contacts are arranged at both ends of the moving contact with the center as the rotation axis, and the two static contacts are respectively opposite to the above moving contacts. In this way, when a large current flows through the two electrical channels of the normally contacted contacts, due to the electromagnetic repulsion force applied between the contacts, the moving contacts rotate and separate from the static contacts. This structure enables the moving contact to rotate only due to electromagnetic repulsion.

In the above-mentioned prior art, since flexible wires are used to connect the moving contacts and the electrical passages, multiple processes are required to process the connection part of the mesh metal wiring, which increases the manufacturing cost. At the same time, a major disadvantage of flexible wires is their relatively short flex cycle life. Since the cross-section is reduced by the network structure, the current density flowing therein is increased, which often causes heating problems. In addition, due to the connection of the crank and connecting rod in the opening/closing mechanism, the problem is that the structure is complicated and the number of parts is increased.

When the arc extinguishing device is used as a measure to eliminate the arc when the circuit breaks, the number of parts increases and the size of the product increases. In addition, since it takes a lot of time to transfer the generated arc to the arc extinguishing grid, there is a limit to the current limiting performance.

In the current limiting structure using electromagnetic repulsion, since the conductor of the moving contact passes through the rotation center of the contact, it brings about the problem that the insulation distance along the rotating shaft of the moving contact is not easy to guarantee. In multi-phase circuit breakers, The electrical insulation distance between phases is shortened.

SUMMARY OF THE INVENTION An object of the present invention is to provide a circuit breaker which improves breaking performance by suppressing arc generation, simplifying the structure and significantly reducing the number of parts.

In order to achieve the above object, the present invention includes a first fixed conductor on the power supply side, a second fixed conductor on the load side, an intermediate fixed conductor inserted between the fixed conductors, a first moving conductor and a second moving conductor, respectively placed on each power supply side And load-side fixed conductors and intermediate fixed conductors, wherein each conductor forms a series electrical channel.

The preferred embodiment includes an opening/closing mechanism such that the first and second moving conductors respectively between the first fixed conductor on the source side and the intermediate fixed conductor and between the intermediate fixed conductor and the second fixed conductor on the load side are substantially Simultaneous opening/closing, additionally including one or more intermediate fixed conductors.

Furthermore, the circuit breaker according to the present invention further includes a movable conductor rotating around a rotating shaft, a first fixed conductor opposite to one end of the movable conductor, a second fixed conductor opposite to the other end of the movable conductor, and the contact portion is arranged such that the first fixed conductor The conductor, the moving conductor and the second fixed conductor are electrically connected in series, and the opening/closing device is used to rotate the moving conductor to open the contact part at the same time, wherein, the moving conductor is arranged at a position separated from the center of the shaft or arranged at the same position as the opening/closing The position where the center of rotation of the mechanism is separated.

Furthermore, in order to achieve the above object, the circuit breaker according to the present invention also includes a supporting part for supporting the moving contact; A moving contact and a second moving contact; the tripping mechanism operates according to the output of the overcurrent detection device, and the driving device is used to drive the supporting part in the tripping direction of 113; the engaging device is used to engage the supporting part to the operating handle, wherein, when When the tripping device releases the engagement of the engaging device, the movement of the support member in the tripping direction is independent of the movement of the operating handle due to the driving device.

Since the moving conductors are respectively arranged between the first fixed conductor and the middle fixed conductor and between the middle fixed conductor and the second fixed conductor, in order to divide/close the first fixed conductor and the middle fixed conductor and the middle fixed conductor and the second fixed conductor, The opening/closing mechanism consists of rigid conductors only, therefore, the flexible conductors used in the existing electrical connection moving conductors are no longer required. Since the opening/closing mechanism substantially simultaneously opens the movable conductors associated with the first and intermediate fixed conductors and the intermediate and second fixed conductors, the opening distance of each contact is shortened.

Furthermore, since multiple contacts in series are opened simultaneously, the overall opening speed between the contacts can be increased for improved current limiting and thus suppression of arcing at each contact. Since the opening/closing mechanism is suitable for opening/closing by the rotary motion or linear motion of the moving conductor, or is suitable for opening/closing by the coupling of the force acting on the moving conductor, there is no need for a crank connecting rod connection, which can reduce parts number and simplified structure.

Furthermore, since the moving conductor is arranged to rotate around the axis of rotation and is located at a certain distance from the center of the axis of rotation, or at a certain distance from the center of rotation of the opening/closing device, the insulation distance between the plates can be maintained.

The operating handle is coaxially arranged to rotate with the rotating shaft of the supporting part, and usually, the engaging device is engaged with the supporting part. Therefore, when the operating handle is turned, the support member can be turned simultaneously, thereby affecting the opening/closing operation of the first moving contact and the second moving contact. In addition, when the support member is driven by the urging means in the tripping direction, it is usually engaged by the engaging means to the operating handle, so that it cannot trip. In the event of overcurrent, the tripping device is activated according to the output of the overcurrent detection device to release the engagement of the engaging device. Therefore, the support member is driven by the driving device and moves in the tripping direction independent of the movement of the operating handle. This enables reliable tripping even when the operating handle lock is ON.

According to the present invention, it is possible to obtain a circuit breaker with improved breaking performance by suppressing arc generation, simplifying the structure and reducing the number of parts.

Fig. 1 is a perspective view showing the internal structure of a circuit breaker according to a first embodiment of the present invention.

Fig. 2 is a sectional view showing the internal structure of a circuit breaker according to a first embodiment of the present invention.

Fig. 3 is a circuit diagram showing an equivalent circuit of the circuit breaker in short circuit according to the first embodiment of the present invention.

Fig. 4 is a characteristic curve showing the relationship between the arc voltage and time of the circuit breaker according to the first embodiment of the present invention.

Fig. 5 is a characteristic curve showing the current limiting effect of the circuit breaker according to the first embodiment of the present invention.

Fig. 6 is a perspective view showing the internal structure of a circuit breaker according to a second embodiment of the present invention.

Fig. 7 is a sectional view showing the internal structure of a circuit breaker according to a second embodiment of the present invention.

Fig. 8 is a perspective view showing the appearance of a circuit breaker according to a second embodiment of the present invention.

Fig. 9 is a perspective view showing a state in which a circuit breaker is mounted to a switchboard according to a first embodiment of the present invention.

Fig. 10 is a perspective view showing the internal structure of a circuit breaker according to a third embodiment of the present invention.

Fig. 11 is a perspective view showing a contact structure of a circuit breaker according to a third embodiment of the present invention.

Fig. 12 is a perspective view showing a contact structure of a circuit breaker according to a third embodiment of the present invention.

Fig. 13 is a perspective view showing the internal structure of a circuit breaker according to a fourth embodiment of the present invention.

Fig. 14 is a perspective view showing the structure of a rotating member in a circuit breaker according to a fifth embodiment of the present invention.

Fig. 15 is a partially cutaway perspective view showing the "on" state of a circuit breaker according to a sixth embodiment of the present invention.

Fig. 16 is a perspective view showing structures of a holding member and an operating handle in a circuit breaker according to a sixth embodiment of the present invention.

Fig. 17 is a partially cutaway perspective view showing an off state of a circuit breaker according to a sixth embodiment of the present invention.

Fig. 18 is a partially cutaway perspective view showing a tripped state of a circuit breaker according to a sixth embodiment of the present invention.

Fig. 19 is a perspective view showing an engaged state of an engaging device in a circuit breaker according to a sixth embodiment of the present invention.

Fig. 20 is a perspective view showing a disengaged state of an engaging device in a circuit breaker according to a sixth embodiment of the present invention.

Fig. 21 is a perspective view showing an engaged state of an engaging device in a circuit breaker according to a sixth embodiment of the present invention.

Fig. 22 is a perspective view showing a disengaged state of the engaging means in the circuit breaker according to the sixth embodiment of the present invention.

Fig. 23 is a partially cutaway perspective view showing a closed state of a circuit breaker according to a seventh embodiment of the present invention.

Fig. 24 is a side sectional view showing a state of mechanical parts in a closed state of a circuit breaker according to a seventh embodiment of the present invention.

Fig. 25 is a partially cutaway perspective view showing an off state of a circuit breaker according to a seventh embodiment of the present invention.

Fig. 26 is a partially cutaway perspective view showing a tripped state of a circuit breaker according to a seventh embodiment of the present invention.

Referring now to FIGS. 1 to 26, the preferred embodiment of the present invention will be described.

First, a first embodiment of the present invention will be described with reference to FIGS. 1 to 5 and 9 .

1 and 2 show the structure of the circuit breaker of this embodiment. In this embodiment, a rotating member 4 made of an insulating material as a supporting member is rotatably journaled in a case by means of a bearing 4c provided substantially at the central portion of the case. The box consists of a shell 1, a molded cover 2 and side panels 2a. Figure 1 shows the state after the side plate 2a is removed. Bearings 4c are formed on the inner surfaces of the molded cover 2 and the side plate 2a. In the assembly method of installing the rotating part 4 to the base body 1 and covering it with the molded cover 2 and the side plate 2a, the molded cover 2 and the side plate 2a can be combined first, or the rotating part 4 can be removed from the In the assembly method of side loading and covering it with the side plate 2a, the housing 1 and the molded cover 2 can be combined together first.

The moving contact base 5 a as the first moving conductor and the moving contact base 5 b as the second moving conductor are fixedly supported by the rotating member 4 . The movable contact bases 5a and 5b are fixed to the rotary member 4 by snapping onto the protrusions 4d and 4e formed on the rotary member 4, or by fitting into grooves formed on the rotary member 4, wherein, The movable contact bases 5 a and 5 b are fixed to the rotating part 4 by relying on the resilience of the protrusions 4 d and 4 e of the rotating part 4 , or relying on the method of screw positioning to the rotating part 4 . In this embodiment, the protrusion 4d is located on the back of the contact 6 on the moving contact bases 5a and 5b, while the protrusion 4e is located on the same side of the contact 6, clamping the contact bases 5a and 5b between them between. The protrusion 4d also serves as a support member, preventing deformation of each movable contact base body due to contact pressure. Each of the movable contact bases 5a and 5b has contacts 6 as movable contacts attached to both ends of the contact base by silver soldering, riveting or the like. The rotating member 4 rotates around a rotating center 4 a formed integrally with the rotating member 4 or formed by a pin passing through the rotating member 4 . The operating handle 3 is installed on the rotating part 4, and its top protrudes from the outside of the molded cover 2. Due to the opening/closing operation of the operating handle 3, the rotating part 4 rotates with the center of rotation 4a as the center of the circle (in FIG. 1, clockwise direction is off, counterclockwise is on). In this embodiment, since the connection terminal, the operating handle and the appearance are compatible with the existing circuit breaker, there is no restriction from the perspective of using the circuit breaker, and the convenience of use is not affected.

The fixed contact base 8 as the first fixed conductor has a power supply side connection terminal 8a at one end, and the other end is attached with a contact 6 as a fixed contact, which is attached to the moving contact with silver soldering, riveting or the like. The moving contact on the contact base 5a is at the opposite position. The intermediate fixed contact matrix 7 as an intermediate fixed conductor is fixed on the housing 1 below the rotating part 4, and the contacts 6 as fixed contacts are attached to its two ends by silver soldering, riveting or other similar methods The position where the part is opposite to the moving contacts of the moving contact bases 5a and 5b. The part where the middle fixed contact base body 7 is installed on the housing 1 is recessed, which is convenient for positioning during fixing. In addition, since the thickness of the board at this place is reduced compared with other parts, the heat generated by the intermediate fixed contact base can be effectively dissipated to the distribution board as shown in FIG. The equipment is mounted on a flat plate 80 . Use silver brazing on the load side conductor 9 as the second fixed conductor, and the contact 6 as the fixed contact is attached to the position opposite to the moving contact on the moving contact base 5b at one end thereof by riveting or similar methods, and the other There is a load side terminal 9a on one end. The fixed contact base 8, the moving contact bases 5a, 5b, the intermediate fixed contact base 7 and the load-side conductor 9 are each in the shape of a flat plate made of rigid conductive material, such as a flat copper strip or similar material. The conductive material is not limited to copper, and can also be other metals like copper alloys, such as infiltrated copper or aluminum, as long as the material is a good electrical conductor, heat conductor, and has proper elasticity to allow the contact to collide. In this embodiment, the power side terminal 8a and the load side terminal 9a have terminal metals 10, which are clamped with screws, respectively, so that when they are assembled to the switchboard, the wires 82 and 84 connected thereto terminal is fixed.

The load-side conductor 9 passes through the current transformer 11 located between the fixed contact and the load-side terminal 9a, and extends to the load side, so as to detect the current value in the electrical channel. The output of the current transformer 11 is sent to the overcurrent detection circuit 12 . The overcurrent detection circuit 12 has a circuit structure as disclosed in Japanese Patent Laid-Open Sho 57-170023. When the current in the current channel, that is, the current flowing through the load side conductor 9, exceeds the rated value, and continues to exceed the time delay In the state of the time interval determined by the characteristics, an output is generated to drive the overcurrent tripping device 13 . The overcurrent tripping device 13 has a structure as described in Japanese Patent Laid-Open Sho 59-189529, wherein, relying on the attraction force of the permanent magnet, the plug 13a is normally attracted, and when the output of the overcurrent detection circuit 12 is driven in reverse, the permanent When the attractive force of the magnet decreases, the plug 13a will stretch out and push the driving part 4b (not shown in Fig. 1 ) on the rotating part, so that the rotating part 4 will rotate clockwise and basically open the contacts at four positions simultaneously. .

Figure 1 shows the on-state of the circuit breaker. In the case of manual opening operation from this state, the operating handle 3 moves to the right in the figure. Since the rotating part rotates clockwise, the moving contacts at four positions The head and the static contact are basically opened at the same time. The manual closing operation is opposite to the opening operation. At this time, the operating handle 3 moves to the left from the opening position in the figure. Due to the counterclockwise rotation of the rotating parts, the moving contacts and static contacts in the four positions Simultaneous contact.

In this embodiment, since the fixed contact base 8, the moving contact bases 5a and 5b, the intermediate fixed contact base 7 and the load-side conductor 9 are each in the shape of a flat plate made of a rigid conductive material, most of the existing Flexible wire conductors used in circuit breakers, thereby eliminating problems with existing circuit breakers such as loose or disconnected flexible wire conductors that limit the life of the circuit breaker.

In this embodiment, the rotary contact opening/closing mechanism is used in series four-point contact structure. There is no need for a crank-link connection or the like in the rotary structure, which can greatly reduce the mechanical parts of the circuit breaker, thereby improving assembly performance and reducing product cost. In addition, the life of the circuit breaker is extended due to the great reduction of mechanical parts.

Furthermore, since the structure of the four-point contacts in series greatly reduces the arc energy when the poles are opened, the generation of arc on each contact can be suppressed, thereby saving the arc extinguishing device, or greatly reducing the size of the arc extinguishing device. At this time, when cutting off the short-circuit current, because the structure of the four-point contact in series greatly suppresses the short-circuit current, there is no limit to the user's selection of the wire support structure, the heat capacity of the load equipment, and the upper and lower ranges of the circuit breaker, providing users with a large the benefits of.

The breaking phenomenon when the short-circuit current is interrupted by the circuit breaker will be described with reference to FIGS. 3 to 5 .

When a short circuit fault occurs in the circuit, a large current flows through the circuit. Due to the repulsion of the large current, when the contacts are opened and the short-circuit current is suppressed, an arc voltage is generated between the contacts, which is called current limiting, and the circuit breaker mechanism then operates to withstand the recovery voltage between the contacts and completes disconnect.

Figure 3 shows the circuit diagram of the equivalent circuit when a short-circuit fault occurs. In this case, establish the following equation

其中   i：短路电流          (A)〔Formula 1〕

where i: short circuit current (A)

e ₀ : current voltage amplitude (V)

R: circuit resistance (Ω)

L: circuit inductance (H)

Va: arc voltage (V)

ω: Power supply voltage angular frequency (Hz)

θ: short circuit phase (rad)

The arc voltage Va is most obviously affected by the displacement of the moving contact base. As a result of various experiences, the arc voltage is approximated as shown in Fig. 4, which can be expressed by formulas (2), (3) and (4).

[Formula 2]

When 0 ≤ t ≤ t ₁

Va＝0 (Formula 2)

[Formula 3]

When t ₁ <t≤t ₂

Va=Vo+a(tt ₁ ) (Formula 3)

[Formula 4]

When t ₂ <t

Va=V ₀ +a(tt ₁ )+b(tt ₂ ) ² (Formula 4)

The current limit value at each moment is calculated by formulas (5), (6) and (7).

[Formula 5]

式中 $\mathrm{\&phi;}={\tan }^{-1}\frac{\mathrm{\&omega;L}}{R}$ when ≤t≤t ₁

In the formula $\mathrm{\&phi;}={\mathrm{the\; tan}}^{-1}\frac{\mathrm{\&omega;\; L}}{R}$

[Formula 6]

When t ₁ <t≤t ₂ $i\left(t\right)=\frac{e_0}{\sqrt{{\mathrm{<figure-callout\; id="2"\; label="R"\; filenames="C9510735800291.png,C9510735800292.png"\; state="\{\{state\}\}">R</figure-callout>}}^2+{\mathrm{\&omega;}}^2{L}^2}}\left\{\sin \right(\mathrm{\&omega;t}+\mathrm{\&theta;}-\mathrm{\&phi;})-{\mathrm{\&epsiv;}}^{-\frac{R}{L}t}\sin (\mathrm{\&theta;}-\mathrm{\&phi;}\left)\right\}$

                                                  

When t ₂ <t $i\left(t\right)=\frac{e_0}{\sqrt{{\mathrm{<figure-callout\; id="2"\; label="R"\; filenames="C9510735800291.png,C9510735800292.png"\; state="\{\{state\}\}">R</figure-callout>}}^2+{\mathrm{\&omega;}}^2{L}^2}}\left\{\sin \right(\mathrm{\&omega;t}+\mathrm{\&theta;}-\mathrm{\&phi;})-{\mathrm{\&epsiv;}}^{-\frac{R}{L}t}\sin (\mathrm{\&theta;}-\mathrm{\&phi;}\left)\right\}$ $-\frac{v_0}{R}\{1-{\mathrm{\&epsiv;}}^{-\frac{R}{L}(t-t_1)}\}-\frac{a}{R}[(t-t_1)-\frac{L}{R}\{1-{\mathrm{\&epsiv;}}^{-\frac{R}{L}(t-t_1)}\left\}\right]$ $-\frac{b}{R}[{(t-t_2)}^2--\frac{2L}{R}(t-t_2)+\frac{2L^2}{R^2}\{1-{\mathrm{\&epsiv;}}^{-\frac{R}{L}(t-t_2)}\left\}\right]$ (Formula 7)

Subtracting the formula V ₀ , a(tt ₁ ) and b(tt ₂ ) ² representing the limiting current by the generation of arc voltage from the current without arc voltage (estimated short-circuit current), yields formulas (5), (6) and (7).

Use equations (8), (9) and (10) to express the current limit.

[Formula 8]

Current limit iv ₀ of V ₀

[Formula 9]

The current limit ia of a(tt ₁ )

[Formula 10]

；从以上所述看出，假定估计的短路短流为i₀，每一时刻的限流值iv₀，ia和ib如公式(11)，(12)和(13)所示，iv₀，ia和ib限制了估计的短路电流如图5所示。b(tt ₂ ) current limit ib of ²

; Seen from the above, assuming that the estimated short-circuit short-circuit current is i ₀ , the current limiting value iv ₀ at each moment, ia and ib are shown in formulas (11), (12) and (13), iv ₀ , ia and ib limit the estimated short-circuit current as shown in Figure 5.

[Formula 11]

When 0 ≤ t ≤ t ₁

i=i ₀ (Formula 11)

[Formula 12]

When t ₁ <t≤t ₂

i=i ₀ -(iv ₀ +ia) (Formula 12)

[Formula 13]

When t ₂ <t

i=i ₀ -(iv ₀ +ia+ib) (Formula 13)

Further, after multiplying both ends of the formula (1) by i, the integral reaches the breaking end time, as shown in the formula (14). ${\&Integral;}_0^{t_{\mathrm{the\; s}}}{e}_{0}i\sin (\mathrm{\&omega;t}+\mathrm{\&theta;})\mathrm{dt}=L{\&Integral;}_0^{t_{\mathrm{the\; s}}}i\frac{\mathrm{di}}{\mathrm{dt}}\&CenterDot;R{\&Integral;}_0^{t_{\mathrm{the\; s}}}{i}^2\mathrm{dt}+{\&Integral;}_0^{t_{\mathrm{the\; s}}}{v}_a\mathrm{idt}$

Circuit energy: $=\frac{1}{2}L{\left[i^2\right]}_0^{t_{\mathrm{the\; s}}}+R{\&Integral;}_0^{t_{\mathrm{the\; s}}}{i}^2\mathrm{dt}+{\&Integral;}_0^{t_{\mathrm{the\; s}}}{v}_a\mathrm{idt}$

supplied from the power $=R{\&Integral;}_0^{t_{\mathrm{the\; s}}}{i}^2\mathrm{dt}+{\&Integral;}_0^{t_{\mathrm{the\; s}}}{v}_a\mathrm{idt}$

Energy (Equation 14) where

It can be seen from formula (14) that the energy provided by the power supply is divided into the energy consumed in the circuit and the arc energy, which is consumed in the interrupter of the circuit breaker.

It can be seen from the above that the arc voltage rise (t ₁ , t ₂ , a, b) and the heat capacity of the arc extinguishing chamber determine the breaking characteristics of the circuit breaker.

Correspondingly, in order to improve the breaking performance, at least the rise of the arc voltage can be made earlier, and the breaking performance is remarkably improved in a circuit breaker with a structure of multiple contacts connected in series.

，每一个灭弧装置只要消耗1/4电弧能量便足够了。In simple terms, in a structure of 2 contacts in series of the same structure, based on the numerical calculation of the approximate arc voltage, the generated arc energy is suppressed to nearly

, each arc extinguishing device only needs to consume 1/4 arc energy.

Furthermore, due to the increase in the number of contacts, the arc energy decreases. As the number of contact pairs increases, compared with the required breaking distance at the rated current given in Table 1, the actual breaking distance is shortened.

〔Table 1〕

The relationship between the number of contacts and the breaking distance of the circuit breaker

                                                                                                   Time period 

(mm) Number) Distance (B)(mm)

(N) (B/N)

(Mm) 30A 12 1 12 30A 12 2 5.4 10.830A 12 4 2.42 9.730A 12 6 1.45 8.7

Actual breaking distance = required breaking distance × 0.9(N-1)

A second embodiment of the present invention will be described with reference to FIGS. 6 to 8 . In the first embodiment (FIGS. 1 and 2), an example of a single-pole circuit breaker is given. In this embodiment, however, bipolar products are constructed in one box. The box is composed of a housing 21, a molded cover 22 and a side panel 2a, and each pole is equipped with a fixed contact base 8 as the first fixed conductor; a moving contact base 5a is the first moving conductor; an intermediate fixed contact base 7 is The middle fixed conductor; the moving contact base 5 b is the second moving conductor, the load side conductor 9 is the second fixed conductor, and the two poles are located on both sides of the rotating part 24 in parallel. In this embodiment, insulation barriers 22a are respectively formed between the power supply side connection terminals 8a and between the load side connection terminals 9a as interpolar insulation between the two poles. As shown in FIG. 7, the rotational fulcrum of the rotating member 24 is located at the rotational center 24a, which is supported by a bearing 24c formed on the inner surface of the molded cover 22 and the side plate 2a. The movable contact bases 5a and 5b are clamped onto protrusions 4d and 4e (not shown in FIG. 6 ) formed on the rotating member 24, fixed on the rotating member 24 in the same manner as the first embodiment . In addition, in this embodiment, the protrusion 4d is located on the back of the contact 6 on the movable contact bases 5a and 5b, while the protrusion 4e is located on the same side of the contact 6, and the movable contact bases 5a and 5b are clamped immediately between them (not shown in Figure 6). In this embodiment, a current transformer 11 is also installed on the load side conductor 9, the output of the current transformer 11 is supplied to the overcurrent detection circuit 12, and under the overcurrent condition, the output of the overcurrent detection circuit 12 drives the overcurrent The tripping device 13 makes the plug 13a protrude, pushes the driving part 4b of the rotating part 24, and the rotating part 24 rotates clockwise, and basically opens the contacts on the four positions at the same time.

The structure of other parts is basically the same as that of the first embodiment. In this embodiment, the movable contact bases 5a, 5b of two poles can be operated simultaneously by one rotating member 24 . It is easy to further promote and apply to three-pole and four-pole products, and can fully adapt to the commonly used three-pole structure. In addition to the two-pole structure, Figure 8 also shows the shape of the three-pole structure.

A third embodiment according to the present invention will be described using FIGS. 10 to 12. FIG. This embodiment presents the configuration of the contacts as a current-limiting repelling type. An example of further improved breaking performance. Fig. 10 shows the overall structure of this embodiment. This embodiment has the same parts and the same structure as the first embodiment, except that the fixed contact base 28, the intermediate fixed contact base 27, the load side conductor 29, the housing 31 and the molded cover 32 are different. In this embodiment, a U-shaped groove is formed near the fixed contact on each fixed conductor of the fixed contact base 28, the middle fixed contact base 27, and the load side conductor 29 to surround the fixed contact so that the current direction is consistent with the fixed contact. The current direction on the moving conductor is opposite, and lugs 28b, 27a, 29b are respectively formed inside the U-shaped groove. The lugs 28b, 27a and 29b can make the direction of the mutual current passing between the opposite fixed conductor and the moving conductor opposite, so that when a large current flows (when a short circuit current is generated) under the action of electromagnetic force, the static contact A repulsive force is added between the contactor and the moving contact, so that it is opened very early, thus providing the effect of significantly inhibiting the short-circuit current (current limiting). Figure 11 is a detailed view of part A. Part A shows the opposite part between the intermediate fixed contact base 27 and the moving contact base 5a, where the current direction B on the moving contact base 5a due to the influence of the U-shaped groove and the lug in the intermediate fixed contact base 27 ₁ and the current direction B ₂ on the lug 27a are opposite to each other, thus generating electromagnetic repulsion. In addition, in addition to the U-shaped groove, as shown in Figure 12, the intermediate fixed contact base 27 can be bent into a U-shaped structure to form a current limiting and repelling structure, and the current direction _B1 on the moving contact base 5a is bent in a U-shaped manner. The current direction _B2 on the lug 27a is opposite, thereby generating an electromagnetic repulsive force.

Referring to FIG. 13, a fourth embodiment of the present invention will be described. In this embodiment, three moving conductors 55a, 55b and 55c and two intermediate fixed conductors 57a, 57b are placed in a box consisting of a housing 51 and a molded cover 52. In this embodiment, three pairs of contacts are used to improve breaking characteristics. Other parts are exactly the same as the first embodiment.

Referring to Fig. 14, a fifth embodiment of the present invention will be described. In this embodiment, the configuration of the rotating member is replaced from the disc shape in other embodiments to a substantially X-shaped rotating member 74 . The rotation center 74a of the rotating member 74 is rotatable by means of the bearings 4c and 24c, as in other embodiments. On the rotating member 74 are formed projections 74d, 74e for clamping the moving contact bases 5a and 5b. The protrusion 74d is located on the back of the contact 6 on the movable contact bases 5a and 5b, while the protrusion 74e is located on the same side of the contact 6. The protrusion 74d also serves as a support member, preventing deformation of each movable contact base due to contact pressure. For other parts, the components in any one of the first to third embodiments can be used.

A sixth embodiment according to the present invention will be described with reference to Fig. 15 to Fig. 22 .

Figure 15 shows the circuit breaker structure of this embodiment, shown in the on state. The circuit breaker of this embodiment includes a fixed contact base 111 as a first fixed conductor inside the box composed of the housing 101 and the molded cover 102, one end of which is connected to the power terminal 111-a, and the other end has a The first static contact 112-a; the conductor 113 is used as the second fixed conductor, one end of which is connected to the load terminal 113-b, and the other end has the second static contact 112-b; the moving contact base 105 has the second fixed contact A moving contact 106-a and a second moving contact 106-b are opposite to the first static contact 112-a and the second static contact 112-b respectively; the rotor 104 is used as a supporting part, and the rotating shaft 104-b Rotating around the center of a circle, it is used to support the moving contact base 105, so that the first moving contact 106-a and the second moving contact 106-b are in contact with the first static contact 112-a and the second static contact 112-b and separation; the operating handle 103 rotates coaxially with the rotating shaft of the rotor 104, and is used to realize the opening/closing operation of the first moving contact 106-a and the second moving contact 106-b; the current transformer 114 and overcurrent detection The circuit 115 is used as an overcurrent detection device for detecting the overcurrent state in the electrical channel from the power terminal 111-a to the load terminal 113-b; the trip unit 116 is used as a tripping device and operates according to the output of the overcurrent detection device; The torsion spring 107 is used as a driving device for driving the rotor 104 in the tripping direction; and the hook 108 is used as an engaging device for engaging the rotor 104 to the operating handle 103 .

The on/off operation of the circuit breaker is performed by the operating handle 103 protruding from the molded cover 102 . As shown in Figure 16, the handle operating part 103a is arranged on the top of the operating handle, and there is a protrusion 103-c as the center of rotation under it, and an extension part 103-b protrudes to the right in addition, and a groove 103d is arranged at the upper end of the extension part 103-b. The protrusion 103 - c is rotatably fitted to the rotor 104 . The rotor 104 rotates around the extension 104-b. There is a torsion spring 107 at the assembly part between the handle 103 and the rotor 104. When the handle is fixed, the torsion spring 107 gives energy to the rotor 104 to rotate clockwise. Like the extension on the operating handle 103, the upper right end of the rotor 104 has an extension 104-c. A slot 104-d is formed in the extension 104-c for receiving the hook 108 therein. Hook 108 is pivotally supported by pin 110 . In addition, viewed from above, the hook 108 relies on the spring 109 to store energy in a clockwise direction. The hook 108 has a driving portion 108-b at one end and an engaging portion 108-a at the other end. In a normal state, the hook engaging portion 108-a extends from the groove 104-d to the operating handle 103 driven by the spring 109, and the rotor 104 engages with the operating handle 103 and rotates together with the operating handle 103. On the rotor 104 there is a moving contact base 105, and moving contacts 106-a and 106-b are provided along a chord of a circle centered on the rotating main body 104-b. The rotor 104 has a protruding portion 104-a covering the base end of the operating portion 103-a on the operating handle 103 on the extended side. In this embodiment, the letter "ON" is marked on the extension 104-a, which is visible through the opening in the molded cover 102 where the handle is placed in the ON state. On the operating handle 103 opposite to the extension of the operating part 103-a, the base 103-e is marked with the letters "OFF", which can be seen through the opening of the molded cover 102 where the handle is placed in the disconnected state . In addition, the base 103-f on the extension part side of the operating part 103-a on the operating handle 103 is marked with letters "TRIP", and they are usually covered and hidden by the protruding part 104-a on the rotor 104, because the protruding part 104- The letters are visible through the opening in the molded cover 102 where the handle is placed in the tripped state caused by the movement of a.

As shown in FIG. 15 , a power connection terminal 111 - a is attached to one end of the static contact base 111 , and the base 111 basically extends in a Z-shaped structure, and a static contact 112 - a is attached to the other end. On the other hand, one end of the conductor 113 is attached with a load terminal 113-b, which basically extends in an L-shaped structure, and the other end is attached with a static contact 112-b. The static contacts 112-a and 112-b are installed at positions opposite to the movable contacts 106-a and 106-b, leaving equal intervals as the intervals for installing the movable contacts. In Figure 15, the rotor 104 is turned clockwise to open the contacts. In order to separate the movable contacts 106-a and 106-b from the static contacts 112-a and 112-b by the rotation of the rotor 104, the movable contact base 105 can be attached to the center of the circle with the rotation center 104-b of the rotor 104 as the center. Go up to the right half of the center of the two chords on the circle whose surface distance is the radius of the moving contact 106-a. The radial (direction from the moving contact 106-a to 106-b) length of the moving contact base 105 is set to be less than half the chord length.

A protrusion 101-b is formed on the inner surface of the molded cover 102 as a seat for the extension portion 103-b so as to stop the rotation of the handle 103 during ON/OFF switching. The protrusion 101-b is not shown in Fig. 17 and Fig. 18 .

The conductor 113 passes through the current transformer 114 between the static contact 112-b and the load terminal 113-b, and relies on it to detect the current in the electrical channel from the power terminal 111-a to the load terminal 113-b . Furthermore, an overcurrent detection circuit 115 is attached to the conductor 113 , and an output consistent with the current value of the main loop of the transformer 114 is input into the overcurrent detection circuit 115 . When the over-current detection circuit 115 detects an over-current, it generates a trip output signal, and the output signal is sent to the trip unit 116 . For the tripping unit 116, a magnetic tripping device or the like is usually used, so that a small amount of energy can be used to trip, for example, a unit is used to stretch out an executive part 116-a through a reverse energy boost, so that the permanent magnet attracts the plug Get set free. In this embodiment, the actuating member 116 - a rests on the driving portion 108 - b of the hook 108 .

Further, a spring 130 is installed on the handle 103, so as to make a quick action during opening and closing operations. The other end of the spring 130 is hung on the protrusion 101 - a of the housing 101 .

Fig. 17 shows the disconnected state of the circuit breaker in this embodiment. Turn the handle operating part 103-a from the state shown in FIG. 15 to the right to perform the disconnection operation. When the handle operating part 103-a was overturned to the right, the entire moving part shown in Figure 16 such as the handle 103, the rotor 104, the hook 108, and the protrusion 104-b on the rotor 104 mounted on the housing 101 as a rotation Center turns clockwise. Due to the rotation of the handle 103, the upper end of the spring 107 moves to the right, and when the center line of the spring 107 exceeds the center of the rotor protrusion 104-b, only the rebound of the spring force direction makes the whole moving part rotate rapidly. When the moving part is further rotated, the handle part 103-b is stopped by the protrusion 101-b on the housing, and the rotation is stopped.

Figure 18 shows the tripped state of the circuit breaker in this embodiment. The current transformer 114 detects the main circuit current, and its output is sent to the overcurrent detection circuit 115 . If the current exceeds the rated current in the main circuit, the overcurrent value is judged by the overcurrent detection circuit 115, and then a characteristic trigger signal defined in an inverse time-lag manner is sent from the overcurrent detection circuit 115 as an output for tripping to the trip unit 116. The actuating portion 116-a of the trip unit 116 pushes the driving portion 108-b of the hook 108 due to the burst of the trigger signal. 19 to 22 illustrate the action of the hook 108 . Figures 19 and 21 show the states of the hook 108 in the on and off states of the circuit breaker. Fig. 19 is the state of the hook 108 on the rotor 104, and Fig. 21 is the state of engagement of the hook 108 and the handle groove 103-d. In this state, since the driving part 108-b is not subject to the pressure of the implementing part 116-a, the engaging part 108-a on the hook protrudes from the groove 104-d of the rotor 104, as shown in Figure 19, and engages The groove 103-d on the handle is as shown in FIG. 21 . The pin 110 is not shown in FIG. 19 and the rotor 104 is not shown in FIG. 21 . Figure 20 and Figure 22 are the state of the hook in the circuit breaker trip state. Figure 20 shows the state of the hook 108 on the rotor 104, and Figure 22 shows the state of engagement of the hook 108 and the handle groove 103-d. When the overcurrent occurred, the driving part 108-b of the hook 108 was pushed because the executive part 116-a stretched out suddenly, so that the hook 108 could rotate around the locking nail 110 in the direction opposite to the energy storage of the spring 109 (viewed from above) counterclockwise), as shown in Figure 20. The hook engaging portion 108-a disengages from the groove 103-d of the handle, as shown in FIG. 22, and the engagement between the handle 103 and the rotor 104 is released. Then, under the elastic force of the spring 130, the rotor 104 rotates clockwise with the assembly part of the protrusion 103-c on the handle as the rotation center, so that the movable contacts 106-a, 106-b are separated from the static contacts 112- a and 112-b, provide an open state of the contacts, thereby breaking the circuit. In this case, since the rotor 104 can move in the tripping direction regardless of the operation of the operating handle 103, it can still trip if the operating handle 103 is locked in the ON state, and a freely tripping circuit breaker is obtained.

Further, in this case, only relying on the rotation of the rotor 104 to move the extension 104-a, the letters "TRIP" hidden on the base 103-f of the operating handle 103 pass through the handle opening on the molded cover 102 ( edge) is displayed.

This embodiment can significantly reduce the number of parts of the mechanical part and improve the assembly performance, thereby greatly reducing the cost of the product, and on the other hand, improves the reliability of the product due to the reduction in the number of parts.

A circuit breaker according to a seventh embodiment of the present invention will be described with reference to Fig. 23 to Fig. 26 . This embodiment applies to a relatively large number of values (225A configuration to 400A configuration).

23 and 24 respectively show the overall structure and the structure of the main components in the ON state with the contacts closed.

The circuit breaker of this embodiment includes a static contact base 211 as the first fixed conductor on the power supply side; a conductor 213 as the second fixed conductor on the load side; a fixed contact base 207 as an intermediate fixed conductor, placed between the first fixed conductor and the second fixed conductor Between two fixed conductors; the moving contact base 205, as the first moving conductor, is placed between the contact base 211 and the fixed contact base 207; the moving contact base 206, as the second moving conductor, is placed in the static contact base Between 207 and the conductor 213; the rotor 204 is rotatably arranged as a support member to support the moving contact bases 205 and 206. In addition, it also includes a heating element 122 and a bimetal 125; and a fixed iron core 123 and a moving iron core 124 as an overcurrent detection device for detecting an overcurrent state in the electrical channel from the static contact base 211 to the conductor 213 The hook 208 acts as a tripping device, which acts according to the output of the current detection device. When the tripping device operates, the rotor 204 acts in the direction of tripping, which has nothing to do with the operation of the operating handle 230 .

Since the operating force of a large-capacity circuit breaker is large, the handle 230 is reinforced with a metal handle rod 117 . The U-shaped groove 117-a on the handle bar fits on the protrusion 118-a of the fixed frame 118 as the base of the assembled mechanical part, and rotates with the protrusion 118-a as the center of a circle. In addition, the hook 208 is fixed to the fixing frame 118 at the hook hole 208-a by means of a pin, and can rotate. The hook top 208 - b engages the trip metal 119 . The tripping metal 119 is supported on the fixed frame 118 by means of a pin, and can rotate like the hook 208 . The other end of the trip metal 119 is engaged to the interlock plate 120 . The trip metal 119 and the interlock plate 120 are charged clockwise by the spring 132 . The center of rotation 204 - a of the rotor 204 is also fitted to the fixed frame 118 . Both ends are respectively attached with moving contacts 112-a, 112-b and the moving contact base body 206 is installed on the rotor 204 so as to stop the static contacts 106 attached to the static contact base body 211 and the second contact base body 207 .

The stationary contact 106-d attached to the top of the conductor 213 abuts against the moving contact 112-d at the end. The other end of the conductor 213 is connected to the heating element 122, and the other end of the heating element constitutes the load side terminal base 122-b. The fixed iron core 123 and the moving iron core 124 are arranged around the conductor, the bimetal 125 is connected with the heating element 122 , and an adjusting screw 126 is installed on the top of the bimetal 125 .

In addition, a spring 130 is connected between the handle rod 117 and the rotor 204 .

Relying on the rod 133, the hook 208 and the rotor 204 form a connecting rod. ,

Figure 25 shows the breaking state with the contacts open. For the breaking operation, when the handle 230 is operated to the right in the same manner as in the second embodiment, the rotor 204 is rotated clockwise due to the direction of the force of the spring 130, thereby opening the contacts.

Figure 26 shows the tripping device. When an overcurrent flows in the main circuit, the bimetal 125 is heated by the heating element 122, and the current in the overload range deforms the bimetal 125, or the fixed iron core 123 attracts the moving iron core 124 in the short-circuit current range, making the interlocking plate 120 counterclockwise rotation and tripping metal 119 are thrown off, and tripping metal 119 just rotates clockwise. Due to the rotation, the engagement with the hook top 208 is released, and the hook 208 rotates with 208-a as the center of circle. Due to the effect of the rod 133 connecting the hook 208 and the rotor 204, the rotor 204 rotates clockwise to open the contact. The handle 230 and the handle bar 117 turn rightward with the protrusion 118-a on the fixed frame 118 as the center of a circle, push against the protrusion 208-b of the hook 208, and stop between the on and off positions, the handle 230 indicates TRIP shown in the middle position.

This embodiment is suitable for a relatively large number of circuit breakers, and since the overcurrent detection system is mechanical, its construction is relatively cost-effective. Furthermore, since it is a four-contact system, good breaking performance can be obtained.

Claims (8)

1. A circuit breaker, comprising a fixed conductor and a moving conductor, characterized in that the fixed conductor includes a first fixed conductor on the power supply side, a second fixed conductor on the load side, and a first fixed conductor and a second fixed conductor An intermediate fixed conductor between the moving conductors, the moving conductor includes a first moving conductor placed between the first fixed conductor and the middle fixed conductor, placed between the middle fixed conductor and the second fixed conductor the second moving conductor. 2. The circuit breaker according to claim 1, characterized in that an opening/closing mechanism is provided, so that between the first fixed conductor and the intermediate fixed conductor and between the intermediate fixed conductor and the second fixed conductor The first and the second moving conductors therebetween are respectively opened/closed substantially simultaneously. 3. The circuit breaker according to claim 2, characterized in that, each of said first and said second moving conductors is electrically insulated and attached to a supporting part made of insulating material, and the allocated opening/closing The mechanism makes the rotating motion of the supporting part drive the moving conductor to rotate around the rotation axis, so as to effectively perform the opening/closing operation between each fixed conductor and the moving conductor. 4. A circuit breaker, comprising a fixed conductor and a moving conductor, characterized in that the fixed conductor includes a first fixed conductor on the power supply side, a second fixed conductor on the load side, and a second fixed conductor inserted between the first fixed conductor and the second fixed conductor One or more (N) intermediate fixed conductors, the moving conductors include multiple (N+1) moving conductors placed between each of the fixed conductors. 5. A circuit breaker comprising a housing, fixed conductors, movable conductors, contact portions disposed near side edges of each conductor, and means for rotating said movable conductors to substantially simultaneously activate each of said contact portions The opening/closing operating mechanism for opening/closing, It is characterized in that the moving conductor rotates around the rotation axis in the housing, the fixed conductor includes a first fixed conductor on the power supply side at one end of the moving conductor, and a second fixed conductor at the load side at the other end of the moving conductor, The contact part connects the first fixed conductor, the moving conductor and the second fixed conductor electrically in series, and the opening/closing operating mechanism provides a the joystick. 6. The circuit breaker of claim 5, wherein the moving conductor is arranged at a distance from the axis of rotation such that there is no electrical conductor in the vicinity of the axis of rotation. 7. A circuit breaker, comprising a fixed conductor, a moving conductor, a supporting part for supporting the moving conductor, an operating handle for opening/closing the electrical channel, and an operating handle for detecting the electrical channel an overcurrent detection device in an overcurrent state and a trip device that operates based on the output of the overcurrent detection device, It is characterized in that the fixed conductor includes a first fixed conductor on the power supply side; a second fixed conductor on the load side, and the moving conductor is placed between the first fixed conductor and the second fixed conductor; the electrical A channel extends from the first fixed conductor to the second fixed conductor, and the movement of the support member in the trip direction is independent of the operation of the operating handle when the trip device is actuated. 8. A circuit breaker, comprising a fixed conductor, a moving conductor, a supporting part for supporting the moving conductor, an operating handle for opening/closing the electrical channel, and an operating handle for detecting an overcurrent detection device of the overcurrent state and a trip device operated based on the output of the overcurrent detection device, It is characterized in that the fixed conductor includes a first fixed conductor on the power supply side; a second fixed conductor on the load side; an intermediate fixed conductor placed between the first fixed conductor and the second fixed conductor, and the moving The conductors include a first moving conductor placed between the first fixed conductor and the middle fixed conductor; a second moving conductor placed between the middle fixed conductor and the second fixed conductor; the electrical channel Extending from the first fixed conductor to the second fixed conductor, and the action of the support member in the trip direction is independent of the operation of the operating handle when the trip device is in action.

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