A fuse holder

Abstract

The invention discloses a fuse holder, comprising a shell and an electromagnetic driver; a knife-type fuse and a fuse holder are installed in the shell; the knife-type fuse comprises a metal blade, the metal blade comprises an input blade and a load blade, and contacts are arranged on both sides of the fuse holder, characterized in that: the fuse holder is fixed to the back side of the shell, and the contact is used to contact the metal blade of the knife-type fuse; the electromagnetic driver comprises an electromagnetic coil and a push rod; a spring is connected to the spring holder, a convex portion is arranged in the middle of the spring, a pad body is arranged at the bottom, and a spring is arranged outside the pad body; a suction cup is arranged at the bottom of the spring holder, and the suction cup can be adsorbed on the pad body under the action of the push rod, and when the circuit is broken, the spring releases elastic potential energy, pushes the spring holder to make the load blade pop out. The invention has the following beneficial effects: the fuse holder can pop out the load end of the fuse when the fuse in the fuse body is blown, reduce the influence of the continuous arc on the blown contact, prolong the service life of the fuse holder contact, and has low specification requirements for the arc isolation device and low cost.

Description

Technical Field

[0001] The invention relates to the field of fuse switch installation, and in particular to a fuse holder. Background Art

[0002] Knife-type fuse is a common low-voltage circuit protection device, mainly used to protect power systems and electrical equipment from overcurrent or short circuit damage. It consists of a blade-shaped conductive part and a fuse. There are contacts at both ends that can be inserted into a dedicated fuse holder.

[0003] In the existing fuse holder for knife-type fuses, the blades at both ends of the knife-type fuse are inserted into the corresponding type of fuse holder when in use to connect the circuit. When a short circuit or excessive current occurs, the fuse in the fuse element of the knife-type fuse melts, thereby disconnecting the circuit.

[0004] However, existing fuses will generate a large arc when the power is cut off instantly. The high temperature generated by the high-voltage arc can easily cause the contacts of the fuse holder and the blade surface of the knife-type fuse to be scorched by the high temperature. After a period of use, the service life of the fuse holder contacts will be greatly affected, and the fuse holder contacts need to be replaced.

[0005] Normally, the instantaneous arc generated by the blade at the current output end (load end) will be larger. The main reasons are as follows:

[0006] 1. Current direction:

[0007] The current flows from the power supply to the load. When the fuse blows, the current will tend to continue to flow in this direction.

[0008] 2. Circuit inductance: The inductance in the circuit (especially the inductance on the load side) will try to maintain the continuity of the current. According to Lenz's law, the inductance will generate an induced electromotive force to resist the sudden change of current. This effect is more obvious at the load end because the load end is closer to the inductive components of the circuit.

[0009] 3. Voltage distribution: At the moment of melting, the voltage at the power supply end will drop rapidly, while the load end will generate an instantaneous high voltage due to the inductance effect, which will lead to the formation of a larger arc.

[0010] 4. Fusing process: The fuse usually starts to melt from the middle and then expands to both ends. Due to the direction of current, the complete disconnection of the load end may lag slightly behind the power supply end, which provides more time for the arc to form.

[0011] 5. Metal vapor flow: The metal vapor generated during the melting process will flow in the direction of the current, which also causes a larger arc to form at the load end.

[0012] 6. Circuit characteristics: The load end is usually connected to various devices, which may contain capacitors and inductors, which will release stored energy at the moment of circuit breaking and increase the arc intensity.

[0013] 7. Grounding effect: The power supply end usually has a large potential difference with the ground, while the load end may be closer to the ground potential. This potential difference distribution will also affect the formation of the arc.

[0014] Therefore, generally speaking, the instantaneous arc and the weaker continuous arc generated at the load end are both larger, and during use, the damage to the load end is greater than the damage to the input end. Summary of the invention

[0015] The purpose of the present invention is to provide a fuse holder. The fuse holder can eject the load end of the fuse when the fuse in the fuse body is blown, reduce the influence of the continuous arc on the blown contact, extend the service life of the fuse holder contact, and has low requirements on the specifications of the arc isolation device and low cost.

[0016] The above technical objectives of the present invention are achieved through the following technical solutions:

[0017] A fuse holder comprises a shell and an electromagnetic driver; a knife-type fuse and a fuse holder are installed in the shell; the knife-type fuse comprises a metal blade, which comprises an input blade and a load blade, contacts are arranged on both sides of the fuse holder, and an installation space for installing the knife-type fuse is arranged in the middle of the shell; a plurality of installation areas are arranged in the installation space, and installation grooves are arranged on the upper and lower sides of each installation area, and the contacts of the fuse holder pass through the installation grooves; the fuse holder is fixed to the back side of the shell, and the contacts are used to contact the metal blade of the knife-type fuse; the electromagnetic driver comprises an electromagnetic coil and a push rod, a spring piece is arranged on one side of the push rod, and an inclined surface is arranged on one side of the spring piece; the push rod is used to push the inclined surface of the spring piece when the electromagnetic coil is energized; the spring piece is connected to a spring seat, a protrusion is arranged in the middle of the spring piece, a pad body is arranged at the bottom, and a spring is arranged outside the pad body; a suction cup is arranged at the bottom of the spring seat, and the suction cup can be adsorbed on the pad body under the action of the push rod. When the circuit is broken, the spring releases elastic potential energy to push the spring seat to make the load blade pop out.

[0018] The present invention is further configured such that: the installation groove is funnel-shaped.

[0019] The present invention is further configured as follows: one end of the spring is fixedly connected to a positioning plate, the other end is connected to a spring seat, and the suction cup is used to be fixed on the cushion body.

[0020] The present invention is further configured as follows: a hook is arranged outside the shell.

[0021] The present invention is further configured such that: the spring piece acts on the inclined surface through a push rod of an electromagnetic driver, pushing the spring seat downward, so that the suction cup contacts the pad body.

[0022] The present invention is further configured such that: the spring seat springs up when the circuit is disconnected, pushing the load blade away from the contact, thereby increasing the distance between the load blade and the contact.

[0023] The present invention is further configured such that: the spring piece acts on the inclined surface through a push rod of an electromagnetic driver, pushing the spring seat downward, so that the suction cup contacts the pad body.

[0024] The present invention is further configured such that: the spring seat springs up when the circuit is disconnected, pushing the load blade away from the contact, thereby increasing the distance between the load blade and the contact.

[0025] In summary, the present invention has the following beneficial effects:

[0026] 1. Automatic pop-up function: When the fuse in the fuse body blows, the design can automatically pop out the load end of the fuse. This reduces the impact of continuous arc on the fuse contact, thereby extending the service life of the fuse holder contact.

[0027] 2. Reduce costs: The specifications of the arc isolation device are lower, so the overall cost is lower.

[0028] 3. Improve safety: After the load blade is pushed out, the distance between it and the contact is increased, reducing the damage of the continuous arc to the fuse contact and improving safety.

[0029] 4. Easy to maintain:

[0030] The height of the knife-type fuse after melting is higher than other fuses, which makes it easy to visually identify the fuse that needs to be replaced. Since the bottom load blade has been separated from the contact, the difficulty of replacement is reduced. The replacement process is simplified and the replacement efficiency is improved.

[0031] 5. Prevent accidental falling off: During the ejection process, the input blade at the top of the knife-type fuse remains connected to the contact, preventing the fuse from completely detaching and falling off, avoiding safety hazards and potential damage to other electrical components.

[0032] 6. Stability: When power is turned on, the electromagnetic driver pushes the spring to bend, so that the protrusion abuts against the connecting plate, improving the installation stability of the knife-type fuse.

[0033] 7. Quick response: The high elastic coefficient spring and suction cup design ensure that the elastic potential energy can be quickly released when the power is off, generating a large driving force and realizing the rapid ejection of the load blade. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a schematic diagram of the structure of a knife-type fuse;

[0035] Figure 2 It is a structural schematic diagram of the melting seat;

[0036] Figure 3It is a structural schematic diagram of the fuse holder;

[0037] Figure 4 for Figure 3 A schematic diagram of the structure in the upward direction;

[0038] Figure 5 for Figure 4 A magnified view of area A;

[0039] Figure 6 for Figure 3 A partial view of the middle shrapnel connection structure;

[0040] Figure 7 It is a state diagram of the spring connection structure when power is turned on;

[0041] Figure 8 It is a schematic diagram of the connection status of the knife-type fuse, fuse holder and fuse holder.

[0042] Figure numerals: 1, melt; 2, metal blade; 201, input blade; 202, load blade; 3, connecting plate; 4, connecting plate; 5, slot; 6, fuse seat; 7, contact; 8, housing; 9, hook; 10, installation space; 11, installation area; 12, installation slot; 13, movable slot; 14, positioning plate; 15, pad; 16, spring; 17, spring seat; 170, base; 171, spring piece; 172, protrusion; 173, inclined surface; 18, suction cup; 19, electromagnetic drive; 20, push rod. DETAILED DESCRIPTION

[0043] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "page", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicating orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0044] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features.

[0045] In the description of the present invention, "multiple" means two or more than two, unless otherwise clearly defined. In the present invention, unless otherwise clearly defined and defined, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be internal communication between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0046] The present invention is further described in detail below in conjunction with the accompanying drawings.

[0047] In order to better understand the present invention, the present invention first describes the structure of the knife-type fuse.

[0048] like Figure 1 As shown, the knife-type fuse includes a fuse 1. A corresponding fuse is arranged in the fuse 1 as a fuse body. Metal blades 2 are arranged on both sides of the fuse 1. The metal blades 2 connect the two ends of the fuse to control the on and off of the fuse 1.

[0049] The metal blade 2 is divided into an input blade 201 and a load blade 202. The input blade 201 is connected to the input end of the power supply, and the load blade 202 is connected to various circuit components. The direction of the current is input blade 201-melt 1-load blade 202.

[0050] like Figure 1 , Figure 2 As shown, a connecting plate 3 is provided at the contact position between the melt 1 and the metal blade 2. The connecting plate 3 is made of insulating rubber. A connecting piece 4 is provided at one end of the connecting plate 3. A card slot 5 is provided in the middle of the connecting piece 4. The connecting piece 4 is used to connect the corresponding melt seat 6. In the prior art, two metal blades 2 are respectively inserted into the elastic contacts 7 on both sides of the melt seat 6, and the connecting piece 4 is fixedly connected to the melt seat 6 by bolts, so that the melt 1 is connected to the circuit.

[0051] With respect to the above-mentioned knife-type fuse, the present invention provides a fuse holder.

[0052] like Figure 3 , Figure 4 As shown, a fuse holder includes a housing 8. A hook 9 is arranged outside the housing 8. The hook 9 can be used to hang the housing 8 in a corresponding electrical device. An installation space 10 for installing a knife-type fuse is arranged in the middle of the housing 8. The installation space 10 is divided into a plurality of installation areas 11. The knife-type fuse can be installed in the installation area 11.

[0053] In order to achieve the technical purpose of automatically ejecting the load blade 202 after the fuse in the fuse 1 is blown, the present invention provides funnel-shaped mounting grooves 12 on the upper and lower sides of the mounting area 11. The fuse holder 6 is arranged on the back side of the housing 8, and the contacts 7 on both sides of the fuse holder 6 pass through the mounting grooves 12, and the fuse holder 6 is fixed to the back side of the housing 8 by bolts.

[0054] A movable groove 13 is provided in the middle of the installation area 11. The provision of the movable groove 13 can achieve the purpose of reducing the use of materials and reducing costs.

[0055] like Figure 4 , Figure 5 , Figure 6 As shown, correspondingly, a positioning plate 14 is provided at the end of the movable groove 13. A cushion body 15 made of rubber material is provided in the middle of the positioning plate 14. A spring 16 with a high elastic coefficient is provided outside the cushion body 15. One end of the spring 16 is fixedly connected to the positioning plate 14, and the other end is connected to a metal spring seat 17. Except for being fixedly connected to the spring 16, the rest of the spring seat 17 is freely set and has a high degree of freedom. A suction cup 18 corresponding to the cushion body 15 is provided at the bottom of the spring seat 17.

[0056] The spring seat 17 includes a base 170. The base 170 is fixedly connected to the spring 16. Both sides of the base 170 are integrally provided with spring pieces 171. A protrusion 172 is provided in the middle of the spring piece 171. A slope 173 is provided on one side of the top of the spring piece 171.

[0057] Correspondingly, an electromagnetic driver 19 is provided at the position of the inclined surface 173 of the spring sheet 171 of the housing 8. The principle of the electromagnetic driver 19 is similar to that of the electromagnetic release, and an electromagnetic coil is provided inside. The electromagnetic coil generates a magnetic field when energized. A push rod 20 is provided in the middle of the electromagnetic coil. After energization, the magnetic field generated by the electromagnetic coil drives the push rod 20 to pass through the electromagnetic driver 19 and push out. The above-mentioned electromagnetic driver 19 is independently powered, and the push rod 20 is pushed out after energization.

[0058] Overall workflow:

[0059] like Figure 7 , Figure 8 As shown;

[0060] 1. Install the fuse holder 6 on the back side of the housing 8 and fix the fuse holder 6 with bolts. The contacts 7 on both sides of the fuse holder 6 pass through the installation slots 12. Insert the blades on both sides of the knife-type fuse into the contacts 7 of the fuse holder 6 to preliminarily complete the fixation of the knife-type fuse.

[0061] 2. When the blade of the knife-type fuse is inserted into the contact 7, the upper connecting piece 4 of the knife-type fuse penetrates into the mounting groove 12, and the slot 5 corresponds to the mounting groove 12, and the connecting piece 4 is finally placed on the base 170 of the spring seat 17; the lower connecting piece 4 enters the movable groove 13 and moves freely;

[0062] 3. Power on, the push rod 20 in the electromagnetic driver 19 is pushed out, and it presses against the inclined surface 173 of the spring sheet 171, so that the spring sheet 171 bends. When the spring sheet 171 bends, it drives the raised part 172 in the middle to abut against the connecting plate 3, thereby improving the installation stability of the knife-type fuse. At the same time, the setting of the inclined surface 173 makes the push rod 20 push the spring seat 17 downward in the process of driving the spring sheet 171 to bend, so that the suction cup 18 connected to the base 170 at the bottom of the spring seat 17 moves downward, and the spring 16 begins to compress. Finally, the suction cup 18 continues to move downward until the suction cup 18 is tightly abutted against the pad body 15, and the suction cup 18 is adsorbed on the pad body 15. When a short circuit occurs in the circuit or the instantaneous current is too large, the fuse in the knife-type fuse melts, and the entire circuit is disconnected.

[0063] 4. A large electric arc will be generated when the circuit is broken. The electric arc will damage the load blade 202 of the knife-type fuse. In the power-off state, the push rod 20 returns to the electromagnetic driver 19, so that the protrusion 172 no longer fixes the connecting plate 3. At this time, the suction cup 18 is instantly separated from the pad body 15 due to the action of the spring 16 with a high elastic coefficient. When the suction cup 18 absorbs the pad body 15, the elastic potential energy accumulated by the spring 16 will not be gradually released. When the suction cup 18 is separated from the pad body 15, the elastic potential energy generated by the spring 16 is instantly released, thereby generating a large driving force;

[0064] 5. Under the action of a larger driving force, the spring seat 17 is instantly bounced up, driving the connecting piece 4 on the spring seat 17 to be pushed upward, so that the load blade 202 of the knife-type fuse is pushed out by a larger driving force, so that the load blade 202 is separated from the contact 7, increasing the distance between the load blade 202 and the contact 7, and reducing the damage of the continuous arc to the fuse seat 6 contact 7;

[0065] 6. When the spring seat 17 drives the knife-type fuse to jump upward, the input blade 201 at the top of the knife-type fuse is still connected to the contact 7, thereby preventing the knife-type fuse from falling off the fuse seat 6 to avoid potential safety hazards or severe collisions that damage other electrical components;

[0066] 7. As mentioned above, when the knife-type fuse needs to be replaced, since the load blade 202 at the bottom has been separated from the contact 7, the replacement is easy, and the blown knife-type fuse can be visually checked (the height of the blown knife-type fuse is higher than other knife-type fuses) and replaced, which reduces the replacement process and improves the replacement efficiency.

[0067] This specific embodiment is merely an explanation of the present invention and is not a limitation of the present invention. After reading this specification, those skilled in the art may make non-creative modifications to the present embodiment as needed. However, as long as they are within the scope of the claims of the present invention, they are protected by the patent law.

Claims

1. A fuse holder, comprising a housing (8) and an electromagnetic driver (19); characterized in that: A knife-type fuse and a fuse holder (6) are installed in the housing (8); the knife-type fuse comprises a fuse element (1) and a metal blade (2); the metal blade (2) comprises an input blade (201) and a load blade (202); contacts (7) are arranged on both sides of the fuse holder (6); A connecting plate (3) is provided at the contact position between the melt (1) and the metal blade (2); a connecting piece (4) is provided at one end of the connecting plate (3); a slot (5) is provided in the middle of the connecting piece (4); the connecting piece (4) is used to connect to the melting seat (6); The middle part of the housing (8) is provided with an installation space (10) for installing a knife-type fuse; A plurality of installation areas (11) are provided in the installation space (10), and each installation area is provided with installation grooves (12) on both upper and lower sides, and the contacts (7) of the fuse holder (6) pass through the installation grooves (12); The fuse holder (6) is fixed to the back side of the housing (8), and the contact (7) is used to contact the metal blade (2) of the knife-type fuse; The electromagnetic driver (19) comprises an electromagnetic coil and a push rod (20), a spring sheet (171) is arranged on one side of the push rod (20), the spring sheet (171) is connected to a spring seat (17), a raised portion (172) is arranged in the middle of the spring sheet (171), a cushion body (15) is arranged at the bottom of the spring sheet (171), and a spring (16) is arranged outside the cushion body (15); a slope (173) is arranged on one side of the spring sheet (171); the push rod (20) is used to push the slope (173) of the spring sheet (171) when the electromagnetic coil is energized, so that the spring sheet (171) bends, and when the spring sheet (171) bends, it drives the raised portion (172) in the middle to abut against the connecting plate (3); The bottom of the spring seat (17) is provided with a suction cup (18), and the suction cup (18) can be adsorbed on the pad body (15) under the action of the push rod (20); When the circuit is disconnected, the push rod (20) returns to the electromagnetic driver (19), so that the protrusion (172) no longer fixes the connecting plate (3); the suction cup (18) absorbs the pad body (15) so that the elastic potential energy accumulated by the spring (16) will not be gradually released, and when the suction cup (18) is separated from the pad body (15), the elastic potential energy generated by the spring (16) is released instantaneously, thereby generating a driving force to push the spring seat (17) to eject the load blade (202).

2. The fuse holder according to claim 1, characterized in that: The installation groove (12) is funnel-shaped.

3. The fuse holder according to claim 1, characterized in that: One end of the spring (16) is fixedly connected to the positioning plate (14), and the other end is connected to the spring seat (17). The suction cup (18) is used to be fixed on the pad body (15).

4. The fuse holder according to claim 1, characterized in that: A hook (9) is provided outside the housing (8).

5. The fuse holder according to claim 1, characterized in that: The spring sheet (171) acts on the inclined surface (173) through the push rod (20) of the electromagnetic driver (19), pushing the spring seat (17) downward, so that the suction cup (18) contacts the pad body (15).

6. The fuse holder according to claim 1, characterized in that: The spring seat (17) springs up when the circuit is disconnected, pushing the load blade (202) away from the contact (7), thereby increasing the distance between the load blade (202) and the contact (7).

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