BACKGROUND

Field of the Invention

Described herein are devices relating generally to fuses for use in electrical devices and systems, and specifically to fuses comprising mechanical and/or hermetically sealed features.

Description of the Related Art

In the field of electronics and electrical engineering, various devices can be employed in order to provide overcurrent protection, which can thus prevent short circuits, overloading, and permanent damage to an electrical system or a connected electrical device. Two of these devices include fuses and circuit breakers. A conventional fuse is a type of low resistance resistor that acts as a sacrificial device. Typical fuses comprise a metal wire or strip that melts when too much current flows through it, interrupting the circuit that it connects. Conventional fuses are thus thermal activating solid-state devices.

As society advances, various innovations to electrical systems and electronic devices are becoming increasingly common. An example of such innovations include recent advances in electrical automobiles, which may one day become the energy-efficient standard and replace traditional petroleum-powered vehicles. In such expensive and routinely used electrical devices, overcurrent protection is particularly applicable to prevent device malfunction and permanent damage to the devices. Furthermore, overcurrent protection can prevent safety hazards, such as electrical fires.

Some problems with the utilization of traditional fuses in many modern applications, such as with electrical automobiles, is that many conventional solid-state fuses have difficulty efficiently operating at high currents. Utilizing the electrical automobile example, fuses that will trigger at lower currents will interrupt device function at a much lower current than is actually hazardous, resulting in the automobile becoming unnecessarily powered down. Furthermore, once a conventional fuse is triggered, it is sacrificed and must be completely replaced.

SUMMARY

Described herein are efficient mechanical fuse devices capable of operating at high current. The term “fuse device” is understood to be devices configured such that they have a first non-triggered or “set” position or state, which causes the device to allow current to flow through it, and a second “triggered” position or state, which causes the device to not allow current to flow through it. These mechanical fuse devices can operate at higher currents than conventional solid-state fuse devices and in some embodiments, the fuse devices can be “reset” such that the devices can be reusable.

In some embodiments, the fuse devices comprise electromagnetic components. In some embodiments, the fuse devices are configured in a set orientation by one or more mechanical components and are triggered when a desired current level causes an electromagnetic field to generate a force sufficient to overcome the force of the mechanical components. In some embodiments, one or more components of the fuse devices can also be housed within a hermetically sealed housing.

In one embodiment, a fuse device comprises a body comprising at least one body portion and internal components within the fuse device configured to change the state of the fuse device between a set state allowing current flow through the device and a triggered state which interrupts current flow through the device. At least some of the internal components are at least partially surrounded by the body portion. The fuse device also comprises contact structures electrically connected to the internal components for connection to external circuitry. The fuse device is configured such that when a threshold current level passes through the internal components, the body changes configuration in response to a generated electromagnetic field, which causes the device to transition to the triggered state.

In another embodiment, a fuse device, comprises a body comprising at least one body portion and internal components, wherein the internal components comprise: fixed contacts electrically isolated from one another, with the fixed contacts at least partially surrounded by at least one body portion, one or more moveable contact, allowing current flow between the fixed contacts when the moveable contact is contacting the fixed contacts, an internal pin component connected to the moveable contact, the pin being biased toward a position that moves the moveable contact out of contact with the fixed contacts, and a pin retention structure configured to hold the internal pin component in place such that the moveable contact is contacting the fixed contacts. The fuse device also comprises contact structures electrically connected to the internal components for connection to external circuitry. The fuse device is configured such that when a threshold current level passes through the internal components, the pin retention structure changes configuration in response to a generated electromagnetic field, which causes the internal pin component to move according to its bias.

In yet another embodiment, a fuse device, comprises a body comprising at least one body portion, moveable and fixed contacts configured to change the state of said fuse device between a set state allowing current flow through the device and a triggered state which interrupts current flow through the device, one or more secondary contact elements electrically contacting the fixed contacts and contact structures electrically connected to said fixed contacts for connection to external circuitry. The fuse device is configured such that when a threshold current level passes through the contact structures and the moveable and fixed contacts, the body changes configuration in response to a generated electromagnetic field, which causes the device to transition to the triggered state. The fuse device is also configured such that the secondary contact element is configured to degrade and no longer contact said fixed contacts when the moveable contact is not contacting the fixed contacts and current is flowing through the secondary contact elements.

In still another embodiment a fuse device comprises a housing with internal components within the housing. The internal components are configured to change the state of the fuse device between a closed state, allowing current flow through the device, and an open state, which interrupts current flow through the device. The fuse device further comprises contact structures electrically connected to the internal components for connection to external circuitry an pyrotechnic features, wherein the fuse device is configured such that when a threshold current level passes through the internal components, the pyrotechnic features activate, which causes the internal components to transition the fuse device to said open state.

In yet another further embodiment, a fuse device comprises a housing, internal components at least partially within he housing, comprising: fixed contacts electrically isolated from one another and at least partially surrounded by the housing; one or more moveable contacts, configured to allow current flow between the fixed contacts when the one or more moveable contacts are contacting the fixed contacts; an internal pin component connected to the one or more moveable contacts, the internal pin component biased toward a position that moves the one or more moveable contacts out of contact with the fixed contacts; and a pin retention structure configured to hold the internal pin component in place such that the one or more moveable contacts are contacting the fixed contacts. The fuse device further comprises contact structures electrically connected to the internal components for connection to external circuitry and pyrotechnic features configured such that when a threshold current level passes through the internal components, the pyrotechnic features activate and interact with the pin retention structure, such that the pin retention structure changes configuration, which causes the internal pin component to move according to its bias.

In still another further embodiment, a fuse device comprises a housing comprising a pyrotechnic feature sub-housing connected to a main housing, moveable and fixed contacts configured to change the state of the fuse device between a closed state allowing current flow through the device and an open state which interrupts current flow through the device, contact structures electrically connected to the fixed contacts for connection to external circuitry, and pyrotechnic features, comprising a pyrotechnic charge and a piston structure. The pyrotechnic features are at least partially within the pyrotechnic feature sub-housing and the pyrotechnic feature sub-housing is configured such that the piston structure is a least partially expelled from the pyrotechnic feature sub-housing when a threshold current level passes through the internal components and the pyrotechnic charge activates, which causes the internal components to transition the fuse device to said open state.

These and other further features and advantages of the invention would be apparent to those skilled in the art from the following detailed description, taken together with the accompanying drawings, wherein like numerals designate corresponding parts in the figures, in which:

