DE102019124858B3 - Blade fuse - Google Patents

Abstract

The invention relates to a flat plug fuse (1), in particular for electric utility vehicles, which has a printed circuit board (10), the printed circuit board (10) having two plug-in tongues (12, 14) and a carrier area (16) formed between the two plug-in tongues (12, 14) ), and a fuse (20), the fuse (20) being mounted on the carrier area (16) of the circuit board (10), electrically connected to both of the tabs (12, 14) and as an SMD fuse or as a THT fuse. Fuse is formed.

Description

The present invention relates to a flat plug fuse and an associated motor vehicle, in particular an electric utility vehicle. The invention is used particularly in the field of motor vehicles, the flat plug fuse also being usable in other fields.

Flat plug fuses are known as a form of fuses that are usually installed in motor vehicles. Flat fuses are pluggable and can therefore be maintained by the user. The design of the blade fuse is standardized according to ISO 8820-3. Known blade fuses designed as fuses are suitable for low voltages of typically 12 V, 24 V, 48 V up to max. 80 V DC.

Classic lead-acid batteries with nominal voltages of up to 80 V are increasingly being replaced by lithium-ion batteries with voltages> 80 V in electric commercial vehicles such as forklifts, wheel loaders or tractors. The flat plug-in fuses known to date are certified for the previous voltage limit of 80 V and can therefore no longer be used.

DE 20 2016 103 239 U1 relates to an electrical safety device accommodated in a housing, in particular for use in vehicles, such as motor vehicles. The electrical safety device with a housing has an electrically insulating carrier, two conductor tracks attached to the carrier and spaced from one another by a gap, and a bow-shaped wire that is used to bridge the gap from a first side of the carrier in two vias, each with a conductor track are electrically connected, plugged in and melted, in particular soldered, on a second side of the carrier opposite the first side. Two contact plates are applied to the first side of the carrier and are electrically conductively connected to one of the two conductor tracks, the carrier being placed in the housing in such a way that the contact plates partially protrude from the housing and are arranged centered with respect to the thickness of the housing.

DE 10 2016 103 220 A1 discloses a securing device which has an electrically insulating carrier, a first conductor track and a second conductor track, which are applied to the carrier and spaced from one another by a gap, and a first and a second through-opening through the carrier and through the first and second conductor tracks, respectively . The gap is bridged by means of a bent wire made of a low-melting metal that is pushed through the through-openings from one side of the carrier and melted on the other side of the carrier.

U.S. 4,755,785 A discloses a fuse assembly in which a molded cover is mounted over a standard pipe fuse. The cover is specially configured so that the fuse caps can be surface mounted to solder points on a circuit board. The cover contains a pair of ears that contact the surface of the circuit board to prevent the assembly from rolling sideways. The cover has a flat surface that can be printed to identify the fuse.

EP 1 213 741 A2 discloses a fuse comprising a fuse element having a fuse section provided between the inner side edges of a pair of parallel flat plate terminal sections and an insulating case covering the inner side edges of the flat plate terminal sections and the fuse section. A central portion of each of the flat plate terminal portions, which is in the lateral position relative to the fuse portion, is retained by a mating terminal of a fuse attachment portion. so that the flat plate connection section is electrically connected to the mating connection.

DE 103 36 786 A1 discloses a fuse comprising a fuse element received in an insulating case made of a synthetic resin. The insulating case, which includes two paired case bodies and an upper wall portion connecting the upper ends of the case bodies, is formed so as to cover the inner edges and upper edges of the tab portions and a fusible portion. A flap is integrally connected to a side edge of a slot-shaped opening which is formed at a lower end of the insulating housing via a thin film hinge in such a way that it can be freely pivoted. After the securing element is inserted into the insulating housing, the flap is pivoted into a closed position and is locked (engaged) with locking projections which protrude from the inner edges of the respective tab section. The unconnected, free end edge of the flap, which rests against the other side edge of the slot-shaped opening, is connected to the housing by ultrasonic welding, heat welding or similar methods.

Against this background, it was an object of the present invention to find a fuse solution that overcomes the previous voltage limit of 80 V and is still compatible can be used with the previous blade fuses.

According to the invention, the object is achieved by a flat plug fuse, in particular for electric utility vehicles, which has: i) a printed circuit board, the printed circuit board having two plug-in tongues and a carrier area formed between the two plug-in tongues, and ii) a fuse, the fuse being attached to the carrier area mounted on the printed circuit board, electrically connected to both of the tabs and designed as an SMD fuse or a THT fuse.

The usual metallic contacts of the known flat fuses designed as fuses are accordingly replaced according to the invention by the tabs of a printed circuit board. Due to the adaptability of the circuit board contour and the contour of the tabs, geometric design freedom is given.

The carrier area connects the two tabs. An electrical connection between the two tabs is only made via the fuse and not directly via the circuit board. The carrier area supports the blade fuse and ensures that the tabs are correctly positioned in relation to one another.

Fuses designed as surface-mounted components are also referred to as SMD fuses and are available for nominal voltages that are above the nominal voltages usually certified for flat plug fuses. Accordingly, it is possible according to the invention to use a type of adapter, namely the printed circuit board, to enable a high degree of flexibility with regard to the adaptation of voltage or current values through the use of different SMD fuses. A separate approval of such flat plug fuses can possibly be dispensed with if the SMD fuse used is already approved.

Fuses designed as wired components are also referred to as THT fuses. Essentially the same applies to THT fuses as stated above for SMD fuses, only for the assembly of THT fuses on the circuit board different manufacturing steps are necessary, as is known to the person skilled in the art.

Flat plug fuses according to the invention can be manufactured without tools, since only standardized manufacturing steps, such as milling and fitting the circuit board, are required. This is particularly noteworthy in comparison to stamped parts that are conventionally used. This simplifies production and can also be automated at the same time. The standard assembly process and tool-free production also enable cost-effective production.

The conductor tracks, via which the fuse is connected to the tabs, must be dimensioned according to the currents for which the flat plug fuse is used.

Different tripping currents of the flat plug fuses can be generated by equipping different SMD fuses.

The tripping current can preferably be coded in an easily recognizable manner by varying the solder mask color of the circuit board and / or by printing the fuse value in plain text, for example in a screen printing process, so that automatic and reliable control is supported in production or in the event of service.

The tabs are preferably metallized. This ensures that a sufficiently good electrical contact is established between the blade terminal fuse and, for example, a fuse holder of a vehicle.

The plug-in tongues preferably have several plated-through holes.

When plugging blade fuses into fuse holders, high forces can occur. Since the plug-in tongues each have several plated-through holes, the high contact forces between the flat plug-in fuse and the fuse holder can be reliably absorbed even under high mechanical and thermal loads. The number of plated-through holes is not restricted and is preferably at least 10, particularly preferably at least 50 and in particular at least 100.

The printed circuit board is preferably dimensioned in such a way that its geometric shape, in particular the plug-in tongues, corresponds to a standardized geometry for flat plug fuses, in particular ISO 8820-3: 2002 (E).

The use of a standardized geometry ensures that the blade-type fuses are compatible with the fuse holders previously used. As a result, it is not necessary to adapt the fuse holders previously used. The same SMD fuses can be used for flat plug fuses of different sizes, in which case only the geometry of the circuit board has to be adapted for different sizes of flat plug fuses. The geometry of the The circuit board includes in particular its contour, the design of the tabs and the thickness of the circuit board.

In addition, further design options, for example in terms of a more compact design or better accessibility for replacing the fuse, for example by enlarging it, can be easily implemented.

The fuse is preferably designed for a voltage value above 80 V. The fuse is particularly preferably designed for a voltage value above 80 V and below 800 V.

This voltage range falls outside the voltage range usually assumed for flat plug fuses, since voltages of, for example, 12 V or 24 V are regularly used in motor vehicles that are usually operated with lead batteries. The flat plug fuses according to the invention can also convert voltages outside of these usual values, for example in the range from 80 V to 350 V, which is of particular relevance for electric utility vehicles.

The flat plug fuse preferably also has a housing, the housing being designed as a handle for inserting the flat plug fuse into a fuse holder.

The support area of the circuit board is preferably arranged in the housing and the plug-in tongues of the circuit board are arranged outside the housing, the housing for inserting the circuit board preferably being in two parts or in one piece with two housing sections connected by a film hinge.

The housing thereby protects the circuit board and the fuse in the area in which no electrical contact with the fuse holder is necessary. Furthermore, however, the housing enables electrical contact to be made in that the plug-in tongues are not arranged within the housing. Production is simplified by the above-mentioned configuration of the housing, since the circuit board can be inserted into the housing before the housing is assembled.

In a further embodiment, the housing is made by overmolding the carrier area of the circuit board with a plastic material, for example with a hotmelt. This prevents access to the carrier area and the fuse, as well as manipulation of the carrier area and the fuse.

The housing is preferably made transparent at least in the area of the fuse. This enables a view of the fuse through the housing, which further supports automatic and reliable control in production or in the event of service.

The object is also achieved by a motor vehicle, in particular an electric utility vehicle, with at least one flat plug fuse according to the invention. The motor vehicle particularly preferably has one of the embodiments of the flat plug fuse described as preferred.

• 1 schematisch und exemplarisch eine Explosionsdarstellung einer Flachstecksicherung,
• 2 schematisch und exemplarisch verschiedene Ansichten einer Flachstecksicherung,
• 3 schematisch und exemplarisch verschiedene Ansichten einer Flachstecksicherung mit versteckten Kanten,
• 4 schematisch und exemplarisch verschiedene Ansichten einer Flachstecksicherung mit alternativem Gehäuse,
• 5 schematisch und exemplarisch eine weitere Ansicht der Flachstecksicherung der 4 sowie einer Leiterplatte.

Further advantages and preferred configurations are described below with reference to the accompanying drawings. Here show:

• 1 schematically and exemplarily an exploded view of a flat plug fuse,
• 2 schematic and exemplary different views of a flat plug fuse,
• 3 schematically and exemplarily different views of a blade fuse with hidden edges,
• 4th schematically and exemplarily different views of a blade fuse with an alternative housing,
• 5 schematically and by way of example another view of the flat plug fuse of 4th as well as a circuit board.

1 shows schematically and by way of example an exploded view of a flat plug fuse 1 . The blade fuse 1 has a circuit board 10 , a backup 20th and an optional housing 30th on.

The circuit board 10 has two tabs 12 , 14th and an intermediate support area 16 on. The tabs 12 , 14th are designed to be accommodated in conventional fuse holders designed for blade-type fuses. Depending on the dimension of the fuse holder, there are other geometries, larger or smaller and also thicker or thinner circuit boards 10 and in particular their tabs 12 , 14th possible.

The flat plug fuse preferably meets standardized geometric requirements, so that, for example, beveled corners depending on the requirements 13 on the tabs 12 , 14th are provided. The beveled corners 13 also simplify the insertion of the blade fuse 1 in a fuse holder and reduce the forces that occur.

In the carrier area 16 is a backup 20th assembled. The backup 20th is as surface-mounted component and is also referred to as an SMD fuse. The backup 20th is therefore from one side to the surface of the circuit board 10 in the carrier area 16 soldered according to known methods.

The choice of fuse 20th depends on the requirements of the use of the blade fuse 1 so that a great deal of flexibility in the choice of tripping currents is made possible. By varying the solder mask color of the circuit board 10 or the tripping current can be coded easily recognizable by means of a plain text print of the fuse value (not shown), so that automatic and reliable control is supported in production or in the event of service.

The tabs 12 , 14th are metallized to establish the electrical connection with the fuse holder. Furthermore, each of the tabs includes 12 , 14th preferably a larger number of comparatively small, metallized holes 100 , in the 2 and 3 are better recognizable to the high contact forces between the blade fuse 1 and to be able to reliably accommodate fuse holders even under high mechanical and thermal loads.

Via one conductor each 15th , 17th in the carrier area 16 is the one with the circuit board 10 associated fuse 20th with the tongue 12 or. 14th electrically connected.

As an alternative to the one shown each one conductor track 15th , 17th on the top surface of the circuit board 10 other designs are also possible. One of the conductor tracks can be 15th , 17th on the top and the other on the bottom surface of the circuit board 10 be trained. Alternatively, there are also multiple conductor tracks on both the top and / or the bottom surface of the circuit board 10 possible. Alternatively or in addition, conductor tracks can also be implemented in intermediate layers if the circuit board 10 is designed as a multilayer circuit board. The exact design, dimensioning and arrangement of the conductor tracks is based on the required cross-section.

The circuit board 10 also has optional openings 19th on. The openings 19th are preferably used for automated handling of the circuit boards 10 , enable the circuit board to be gripped, for example 10 for insertion in the housing 30th .

The case 30th In this example it is designed in two parts with a lower housing part 32 and a housing cover 34 . The circuit board 10 on which the fuse 20th is soldered on, is in the lower housing part 32 inserted and by means of guide grooves 33 guided and held in position. Then the housing cover 34 placed and locked, for example locking lugs 38 in corresponding locking means 37 snap into place. The housing cover 34 also has a guide groove 35 for guiding the circuit board 10 on.

The case 30th is preferably partially or completely transparent and further preferably comprises or consists of a plastic material. One area is particularly preferred 36 of the lower housing part 32 transparent, so that a look at the fuse behind it 20th is made possible. The fuse value of the fuse is particularly preferred 20th recognizable.

2 shows schematically and by way of example a front view 50 , a side view 52 , a top view 54 and a view 56 from below onto the assembled blade fuse 1 .

3 shows a further front view schematically and by way of example 60 , a side view 62 , a top view 64 and a view 66 from below onto the assembled blade fuse 1 , with internal edges being illustrated with dashed lines.

4th and 5 show schematically and by way of example an alternative blade fuse 1 that differ from the in 1 to 3 blade fuse shown 1 through an alternative housing 300 differs.

The case 300 is made in one piece and comprises a first housing section 310 and a second housing section 320 that by means of a film hinge 314 are connected.

For mounting the blade fuse 1 of the 4th and 5 is first the circuit board 10 in the second housing section 320 inserted, the second housing section 320 one for the circuit board 10 Has a suitable recess or guide. The case 300 is then made by folding the two housing sections 310 , 320 along the film hinge 314 closed, with locking means 312 of the first housing section 310 in corresponding locking means 322 of the second housing section 320 engage and the housing 300 secure in the closed position.

In 5 the circuit board is also insulated 10 before installing the fuse 20th shown. This makes it clear that the same circuit board 10 with both the housing 30th as well as the housing 300 is compatible.

Alternative to one of the housings 30th or 300 can the circuit board 10 , more precisely the carrier area 16 the circuit board 10 be encapsulated by a suitable material in order to form a housing through the encapsulation and to protect the internal parts. The overmoulding prevents non-destructive access to the fuse 20th .

Claims (10)

Blade fuse (1), in particular for electric utility vehicles, which has: - A printed circuit board (10), the printed circuit board (10) having two plug-in tongues (12, 14) and a carrier area (16) formed between the two plug-in tongues (12, 14), - A fuse (20), the fuse (20) being mounted on the carrier area (16) of the circuit board (10), electrically connected to both of the tabs (12, 14) and designed as an SMD fuse or as a THT fuse . Blade fuse (1) Claim 1 , wherein the tabs (12, 14) are metallized. Flat plug fuse (1) according to one of the preceding claims, wherein the plug-in tongues (12, 14) have a plurality of plated-through holes (100). Flat plug fuse (1) according to one of the preceding claims, wherein the circuit board (10) is dimensioned such that its geometric shape, in particular the plug-in tongues (12, 14), conforms to a standardized geometry for flat plug fuses, in particular ISO 8820-3: 2002 (E) , corresponds. Flat plug fuse (1) according to one of the preceding claims, wherein the fuse (20) is designed for a voltage value above 80 V, in particular above 80 V and below 800 V. Flat plug fuse (1) according to one of the preceding claims, which further comprises a housing (30), the housing (30) being designed as a handle for inserting the flat plug fuse (1) into a fuse holder. Blade fuse (1) Claim 6 , wherein the carrier area (16) of the circuit board (10) is arranged in the housing (30, 300) and the plug-in tongues (12, 14) of the circuit board (10) are arranged outside the housing (30, 300) and the housing ( 30, 300) for inserting the printed circuit board (10) is preferably two-part or one-part with two housing sections (310, 320) connected by means of a film hinge (314). Blade fuse after Claim 6 , wherein the housing is formed by overmolding the carrier area (16) of the printed circuit board (10) with a plastic material. Blade fuse (1) after one of the Claims 6 to 8th wherein the housing (30) has a transparent area (36) at least in the area of the fuse (20). Motor vehicle, in particular electric utility vehicle, with at least one flat plug fuse (1) according to one of the Claims 1 to 9 .

Images