electrical normally open contact

Abstract

The present invention relates to an electrically normally open contact comprising: a first electrical connection portion (4a) and a second electrical connection portion (4b); a first contact element (6a) electrically connected to the first connection portion; a second contact element (6b) electrically connected to the second connection portion; a connecting element (8) by means of which an electrical connection can be established between the two contact elements; and a driver (10) for realizing relative movement between the contact elements and the connecting element, wherein the connecting element (8) or the contact elements (6a, 6b) are at least partially formed of a conductive porous metal.

Description

Technical Field

[0001] This invention relates to an electrical normally open contact, particularly for motor vehicle wiring, especially motor vehicle power lines, such as battery wiring, battery-motor wiring, battery-starter wiring, battery-generator wiring, or starter-generator wiring. Background Technology

[0002] In automotive and other applications, safety requirements are becoming increasingly stringent. Especially at high currents, it is essential to safely disconnect the circuit in the event of a fault for safety reasons. Users, passengers, and helpers must be safely protected from electric shock.

[0003] In high-voltage applications where voltages sometimes exceed 1000V and currents are high, such as in automotive powertrains, reliable switches are essential to ensure reliable personal protection in the event of a malfunction or collision. One possible safety solution is to short-circuit conductive components via normally open electrical contacts. A short circuit initiated by normally open contacts disconnects the vehicle's power supply downstream of the short circuit. Furthermore, the advantage of short-circuiting is that it eliminates the need for switching under load, where there is always a risk of arcing and the potential for continued current flow. Additionally, normally open contacts can be designed to be unresettable, ensuring permanent protection. Summary of the Invention

[0004] The present invention is based on the purpose of providing normally open electrical contacts for safety-related systems, which are reliably closed and difficult to switch and reset.

[0005] This objective is achieved by the normally open electrical contact according to claim 1.

[0006] To connect normally open electrical contacts to a circuit, such as to a vehicle wiring harness or a vehicle power line, the contacts have at least first and second electrical connection portions. Each corresponding electrical connection portion can be formed as a lug, a bolt, a screw connection, a crimp connection, a round wire, or a flat wire. The normally open electrical contacts can be encapsulated in a separate housing, and the connection portions can be led out from this housing.

[0007] Furthermore, the normally open electrical contact has a first contact element electrically connected to the first connection portion and a second contact element electrically connected to the second connection portion. The electrical contact elements are insulated from each other and spatially separated in the open position. The contact elements are preferably arranged inside the housing of the normally open electrical contact.

[0008] A connecting element is provided to bring two contact elements into contact with each other. The connecting element is made of conductive material and can contact both contact elements simultaneously, thereby creating a short circuit through the contact elements and achieving the closed position of the normally open electrical contacts.

[0009] To bring the connecting element into contact with the contact element, at least one of the contact elements undergoes relative movement, particularly translational movement, relative to the connecting element. In the open position, the connecting element and at least one of the contact elements are spatially separated, and there is no electrical connection between the two contact elements or between at least one of the contact elements and the connecting element. Preferably, no contact element is connected to the connecting element in the open position. However, it is also possible for one of the contact elements to be connected to the connecting element and for a second contact element to be electrically isolated from it. In this case, the relative movement between the contact element and the connecting element causes the second contact element to move relative to the connecting element. However, the connecting element may also move relative to at least one of the contact elements.

[0010] If the connecting element and one or two contact elements move relative to each other, mechanical and electrical contact occurs between the contact elements and the connecting element, and the connecting element forms a short circuit between the two contact elements.

[0011] The conductive material surrounding the connecting element provides good anti-reset protection while being lightweight. This material can be porous. It can be in the form of powder or porous foam. The material can also be a paste or liquid. The material is preferably metallic. The material is conductive.

[0012] It is recommended that the connecting elements and / or contact elements be at least partially formed of a conductive material. At least one of the contact elements may penetrate the material of the connecting element, thereby creating a short circuit in the closed position. The connecting element may also penetrate the conductive material of the contact element, thereby creating a short circuit in the closed position. In the following text, the terms "penetrate" and "immerse" may be understood synonymously. Porous materials will be described in several places below. These descriptions also apply accordingly to paste, liquid, or powder materials. For example, liquid metal may be mercury.

[0013] According to one embodiment, by means of relative movement between at least one of the contact elements and the connecting element, at least one, preferably two, of the contact elements is immersed in the conductive material of the connecting element, or the connecting element is immersed in the conductive material of at least one of the contact elements. Immersion can be understood as mechanical penetration, particularly in the form of piercing or nailing. Penetration into the conductive material can be facilitated by appropriate design of the contact elements or connecting elements.

[0014] A connection is established between the intruding element and the intruded element. The intruding element can be at least one of the contact elements, and the intruded element is, in this case, a connecting element. The intruding element can be a connecting element, and the intruded element is, in this case, at least one of the contact elements. The intruded element can be at least partially made of a conductive material.

[0015] To prevent loosening of already inserted components, it is recommended that the inserted components be formed with undercuts and / or hook shapes and / or barbs that widen against the direction of insertion. The inserted component can be one of the contact elements in the connecting element or a connecting element immersed in at least one contact element.

[0016] In the terminated position, i.e., when the relative movement between at least one contact element and the connecting element ends, one or both contact elements may be surrounded by the conductive material of the connecting element, or the connecting element may be surrounded by the conductive material of at least one contact element. Here, particularly the end regions of the separately penetrated elements are preferably completely surrounded by conductive material. There are mechanical and electrical connections between the penetrated elements and the conductive material. Preferably, both contact elements penetrate the conductive material of the connecting element. However, if an electrical connection already exists between one of the contact elements and the connecting element in the disconnected position, only one contact element may penetrate the conductive material.

[0017] Conversely, in which at least one, preferably two, contact elements are formed of or have a conductive material, it is suggested that the connecting element already embedded in the conductive material be surrounded by the corresponding conductive material of at least one of the contact elements. It is particularly suggested that the corresponding end regions of the connecting element be completely surrounded by the corresponding conductive material.

[0018] Encirclement can be understood as the penetrating element being completely surrounded by conductive material along its outer periphery and in contact with it in a surrounding manner. The end region can be the end face of the penetrating element and the surface facing away from the end face. The penetration depth can range from a few millimeters to a few centimeters. The greater the penetration depth into the conductive material, the larger the contact surface, and thus the greater the conductivity or electrical conductivity between the connecting element and the contact element.

[0019] According to one embodiment, the conductive material is suggested to be a porous metal, particularly an open-cell or closed-cell metal foam, especially made of aluminum or copper. Whereas mentioned below, foam or metal foam is always understood to mean porous metal, where in this context, foam is understood only as one embodiment of porous metal.

[0020] According to one embodiment, the porous metal has an average pore size between 0.2 mm and 0.4 mm. The smaller the pore size, the denser the porous metal, and the larger the contact area between the porous material and the inserted and penetrated elements.

[0021] As already explained, the contact element penetrates into the connecting element, or vice versa. To facilitate penetration, the penetrating element has a serrated geometry, such as a cone. It is recommended that the tip of the contact element points towards the connecting element, or that the tip of the end of the connecting element points towards the corresponding contact element. Each corresponding tip is preferably formed in a serrated shape. The penetrating element may also be formed in a cutting edge shape.

[0022] Electrical and mechanical contact is achieved by driving the tip into the porous metal using an actuator to accelerate it. Due to the metal's porosity, penetration is possible while simultaneously achieving a large holding force.

[0023] According to one embodiment, it is proposed that the contact element and the connection portion be integrally formed. Therefore, the connection portion is directly driven into the conductive material.

[0024] According to one embodiment, it is proposed that the connecting element be formed as a conductive bridge and that the connecting element be immersed in the conductive material of the contact element by relative movement. It should be noted that it may be sufficient if only one end of the connecting element is immersed in a contact element and the other end of the connecting element is already connected to another contact element. This applies to all embodiments.

[0025] According to one embodiment, it is suggested that the conductive material be completely surrounded by a housing. However, it is also preferred that an insulating material be disposed on the surface of the conductive material, into which at least one of the contact elements or connecting elements penetrates. This insulating layer prevents unwanted contact, for example, caused by vibration. A sufficiently large force is required to penetrate the insulating layer or housing. This force is applied by means of acceleration generated by an actuator. Upon immersion, the connecting element or contact element breaks through the housing wall due to acceleration by the actuator.

[0026] The housing is preferably made of insulating material to prevent accidental contact.

[0027] According to one embodiment, after immersion, the conductive material completely surrounds the connecting element and / or contact element, thereby forming a force-fit connection between the connecting element or contact element and the conductive material.

[0028] The actuator can be electrical, electromechanical, magnetic, pyrotechnic, or similar. Electromechanical actuators can be, in particular, electrically triggered spring actuators. Magnetic actuators can be, in particular, relay actuators. Pyrotechnic actuators can be implemented using a pyrotechnic igniter, which can be triggered by an electric ignition pulse.

[0029] Porous metals can be manufactured in various ways, with foaming by foaming agents being particularly effective. Sintering of metal powders can also produce porous materials. Introducing a foaming agent into metal powder and treating the metal-foaming agent mixture, especially by heating, causes the foaming agent to release gas and bubble, thereby forming pores. Alternatively, a mixture of metal and salt can be formed during casting, followed by washing away the salt, leaving a porous metal matrix. Attached Figure Description

[0030] The invention will be explained in more detail below with the aid of the accompanying drawings, which illustrate embodiments. In the drawings:

[0031] Figure 1a A normally open contact in the disconnected position according to the first embodiment is shown;

[0032] Figure 1b It shows the closed position. Figure 1a The normally open contact shown;

[0033] Figure 2a A normally open contact in the open position according to one embodiment is shown;

[0034] Figure 2b It shows the closed position. Figure 2a The normally open contact shown;

[0035] Figure 3a A normally open contact in the open position according to one embodiment is shown;

[0036] Figure 3b It shows the closed position. Figure 3a The normally open contact shown. Detailed Implementation

[0037] Figure 1a A normally open contact 2 with a first connecting portion 4a and a second connecting portion 4b is shown. The connecting portions 4a and 4b can be formed as flat or circular components. In particular, the connecting portions 4a and 4b can be formed as a lug, a post, a crimp connection, a brazed connection, a fusion weld connection, or a similar structure. The connecting portions 4a and 4b can be bimetallic or made of a single metal. In particular, the connecting portions 4a and 4b can be formed of copper or aluminum.

[0038] Contact elements 6a and 6b may be integrally formed with connecting portions 4a and 4b, or may only be in electrical contact with them. Contact elements 6a and 6b may be made of the same metal as or a different metal from connecting portions 4a and 4b. Contact elements 6a and 6b may be metal-coated. Contact elements 6a and 6b may be made of copper or aluminum, in particular.

[0039] Contact elements 6a and 6b can be formed into the shape of protrusions on the end face side and point in the direction of connecting element 8.

[0040] The connecting element 8 may have a housing 8a and a metal foam 8b disposed within the housing 8a. The metal foam 8b is described below as a representative of porous metals, and therefore the following description is also applicable to any other porous metal.

[0041] The housing 8a is made of insulating material, especially plastic, and preferably completely surrounds the metal foam 8b. An igniter-type driver 10 can be provided on the side of the connecting element 8 opposite to the contact elements 6a, b. An electrical pulse can trigger the driver 10 via the ignition wire 12, causing air pressure to accelerate the connecting element toward the contact elements 6a, b.

[0042] exist Figure 1a In the illustrated embodiment, the connecting element 8 is movably arranged in the channel 14 and, in particular, can move in the channel 14 along the movement direction 16. The movement of the connecting element 8 in the channel 14 along the movement direction 16 is triggered by the driver 10.

[0043] Upon triggering, an ignition pulse is transmitted through ignition wire 12 and driver 10 is activated. The resulting air pressure causes connecting element 8 to move in the direction of movement 16. The impact on connecting element 8 is large enough that contact elements 6a and b penetrate housing 8a and enter the metal foam 8b. Mechanical and electrical connections are formed between the end faces of contact elements 6a and b and the metal foam 8b. A short circuit is formed between contact elements 6a and b via the foam metal 8b, and normally open contact 2 is in the closed position.

[0044] Connecting element 8 remains stationary in this closed position. Because the tips of contact elements 6a and 6b are completely mechanically surrounded by metal foam 8b, connecting element 8 is securely retained on contact elements 6a and 6b and prevents repositioning. Barbs or undercuts (not shown) may also be provided on the tips of contact elements 6a and 6b to prevent connecting element 8 from moving in the opposite direction 16.

[0045] Figure 2a Another embodiment is shown, in which the contact element 6a is mounted in a manner that allows it to pivot about the connecting element 4b about the axis 6c. The contact element 6a is connected to the connecting element 8, particularly to the metal foam 8b. The connecting element 8, together with the metal foam 8b, is arranged inseparably at the contact element 6a, for example, through a mating engagement between the metal foam 8b and the surface material of the contact element 6a.

[0046] The actuator 10' is formed by a spring, which can be released electromagnetically, for example.

[0047] Upon triggering, the driver 10' is activated by an ignition pulse, and the contact element 6a, along with the connecting element 8, accelerates along the direction of the contact element 6b. Due to this relative motion, the contact element 6b penetrates into the metal foam 8b, as... Figure 2b As shown, a short circuit is formed between contact element 6a and contact element 6b.

[0048] According to another embodiment, the contact elements 6a and 6b can also accelerate in the moving direction 16 toward the connecting element 8, such as... Figure 3a As shown in Figures 1 and 2. Contact elements 6a and 6b are connected to connecting portions 4a and 4b, allowing the contact elements 6a and 6b to move in the moving direction 16. A pin 18 may be provided between the driver 10 and the contact elements 6a and 6b to ensure uniform acceleration of the contact elements 6a and 6b.

[0049] An insulating layer 8c may be provided between the end faces of contact elements 6a and b and the connecting element 8. Figure 3a The normally open contact 2 is shown in its open position. When triggered, the driver 10 is actuated and the contact elements 6a and b accelerate toward the connecting element 8 in the direction of motion 16 via the pin 18. The magnitude of the motion pulse causes the contact elements 6a and b to penetrate the insulating layer 8c and enter the metal foam 8b. Figure 3b The closed position is shown, in which a short circuit is formed between contact elements 6a and b via metal foam 8b.

[0050] Explanation of reference numerals in the attached figures

[0051] 2 Normally open contacts

[0052] 4a, b connection parts

[0053] 6a, b Contact elements

[0054] 6c axis

[0055] 8 Connecting elements

[0056] 8a Housing

[0057] 8b Metal Foam

[0058] 8c insulation layer

[0059] 10,10' drive

[0060] 12 Ignition Lines

[0061] 14 channels

[0062] 16. Movement direction

[0063] 18 sales

Claims

1. A normally open electrical contact, the normally open electrical contact comprising: The first electrical connection and the second electrical connection, The first contact element electrically connected to the first connecting portion, The second contact element is electrically connected to the second connecting portion. A connecting element, by means of which an electrical connection can be established between two contact elements, and A driver that enables relative movement between at least one of the contact elements and the connecting element. Its features are, The connecting element or contact element is at least partially formed of a conductive, porous material, wherein The contact element, at least one of which is immersed in a conductive, porous material, is surrounded by the conductive, porous material of the connecting element, or A connecting element immersed in at least one of the contact elements in a conductive, porous material is surrounded by a corresponding conductive, porous material of at least one of the contact elements to prevent the connecting element from resetting from the porous material.

2. The normally open electrical contact according to claim 1, Its features are, The normally open electrical contact is used for motor vehicle wiring.

3. The normally open electrical contact according to claim 2, Its features are, The vehicle wiring harness is the vehicle power supply cable.

4. The normally open electrical contact according to claim 1, Its features are, At least one of the contact elements has its end region surrounded by a conductive material, or the corresponding end region of the connecting element is completely surrounded by a corresponding conductive material.

5. The normally open electrical contact according to claim 4, Its features are, At least one of the contact elements has its end region completely surrounded by a conductive material.

6. The normally open electrical contact according to claim 1, Its features are, Conductive materials are porous metals.

7. The normally open electrical contact according to claim 6, Its features are, The porous metal is an open-cell or closed-cell metal foam.

8. The normally open electrical contact according to claim 6, Its features are, The conductive material is made of aluminum or copper.

9. The normally open electrical contact according to claim 6, Its features are, Porous metals have an average pore size between 0.2 mm and 0.4 mm.

10. The normally open electrical contact according to claim 1, Its features are, At least one of the contact elements is formed in a spiky shape, and the tip of the contact element points toward the connecting element, or the end of the connecting element is formed in a spiky shape and the tip of the end of the connecting element points toward the corresponding contact element.

11. The normally open electrical contact according to claim 1, Its features are, At least one of the contact elements is integrally formed with at least one of the connecting portions.

12. The normally open electrical contact according to claim 1, Its features are, The connecting element is formed as a conductor bridge and is immersed in the conductive material of at least one of the contact elements by relative movement.

13. The normally open electrical contact according to claim 1, Its features are, The conductive material is completely surrounded by the housing, and the connecting elements and / or contact elements break through the housing wall when immersed in the conductive material.

14. The normally open electrical contact according to claim 13, Its features are, The housing is made of insulating material.

15. The normally open electrical contact according to claim 1, Its features are, After immersion, the conductive material completely surrounds the connecting element and / or contact element, thereby forming a force-fit connection between the connecting element or contact element and the conductive material.

16. The normally open electrical contact according to claim 1, Its features are, The actuator can be electrical, electromechanical, magnetic, pneumatic, and / or pyrotechnic.

17. The normally open electrical contact according to claim 6, Its features are, The porous metal is formed by foaming a foaming agent in a metal-foaming agent mixture, or by washing away the salt from a cast metal-salt mixture.

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