GB1577904A - Electrical devices - Google Patents

Description

(54) IMPROVEMENTS IN OR RELATING TO ELECTRICAL DEVICES (71) We, P.R. MALLORY & CO.

INC., a corporation organised and existing under the laws of the State of Delaware, United States of America of 3029 East Washington Street, Indianapolis, State of Indiana, United States of America, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed to be particularly described in and by the following statement: The present invention relates to an electrical device with means for rendering the device electrically inoperative upon the occurrence of a predetermined condition, and, more particularly, to means for rendering the device electrically inoperative upon the occurrence of predetermined movement by at least one of the components with respect to another component of the device.

The present invention is applicable to an electrical device which, under certain circumstances, is capable of generating or evolving fluid during storage and/or operation. Usually, the evolution or generation of fluid up to a certain amount can be accommodated within the housing of the electrical device; however. accumulation of excess fluid within the housing may cause the appearance of a rupture in a wall of the housing through which fluid and. perhaps, other matter of the electrical device may be ejected. Loss of fluid and/or other matter of the electrical device through the rupture may have a harmful effect on the desired operational characteristics of the device.

The ejection of a fluid that is combustible from the electrical device is undesirable for obvious reasons. Furthermore. ejected fluid which contacts an adjacent electrical component may adverselv react with the contacted component or may cause the contacted component to operate intermittentlv.

The present invention providers an electrical device comprising a housing having a wall carrying an electrical terminal, an electrical component with anode and cathode connection elements within the housing, an apertured non-flexible member disposed between the electrical component and the said wall of the housing, a part of the electrical terminal extending freely through an aperture in the non-flexible member the cross sectional area of which aperture is greater than that of the said part of the terminal, which latter is in electrical contact with one of the connection elements at a location between the said non-flexible member and the said electrical component, this connection element having such a configuration in relation to the aperture of the non-flexible member that displacement of the terminal relative to the non-flexible member in a direction away from the said electrical device causes the connection element and the electrical terminal to become electrically uncoupled rendering the electrical device inoperative.

In order that the present invention be more readily understood. two embodiments thereof will now be described. by way of example, with reference to the accompanying drawings. in which: Figure I is a side view, partly in section, of an electrical device formed as a first embodiment of the invention: Figure 2 is a side view, partly in section. of the electrical device shown in Figure 1 wherein the connection elements and the electrical terminals are electrically uncoupled rendering the electrical device inoperative; Figure 3 is a top view of the non-flexible member of the embodiment shown in Figure l and Figure 2; Figure 4 is a partial side view of a three terminal electrical device formed 'as a second embodiment of the invention: and Figure 5 is a top view of the non-flexible member of the embodiment shown in Figure 4.

An electrical device comprises a housing having a wall carrying at least one terminal.

Within the housing is an electrical component with anode and cathode connection elements. An apertured. substantially nonflexible member is retained between the electrical component and a wall of the housing. A protrusion of the terminal extends through an adjacent aperture in the non-flexible member. One of the connection elements is electrically coupled to the protrusion of the terminal. The connection element electrically coupled to the protrusion of the terminal has such a configuration in relation to the adjacent aperture of the non-flexible member that displacement of the protrusion of the terminal relative to the non-flexible member causes the connection and the terminal to become electrically uncoupled rendering the electrical device inoperative.

Referring now to Figure 1 of the drawing.

an electrical device 10 includes a housing 11.

terminal assemblies 12 and 13. an electrical component 14 within the housing. and a liquid (not shown) in the housing and contacting the electrical component. The liquid may be a dielectric liquid such as dioctyl phthalate. or chlorinated diphen!l.

or the like. In its preferred embodiment. the illustrated electrical component 14 is a convolutely wound capacitor roll includine anode and cathode metallic foils (not shown) with a dielectric cellulosic paper separator (not shown) between and separating each of the metallic foils. The metallic foils are of any suitable material such as aluminum or the like. The cellulosic paper is any suitable paper such as Kraft (Registered Trade Mark) paper. The paper is impre gutted with dioct!'l phthalate dielectric liquid with or without additives such as an epoxide. The housing Ii includes a wall 16 which is retained in place by crimping or rolling an area 17 of the cover over edge 18.

The housing 11 including the wall 16 are fabricated from any suitable material such as aluminum.

Terminal assembly 12 includes a rivet 19 having a shank 2í) projecting through aperture 21 in the wall 16. An external terminal cnd 22 is suitably attached to the shank 2().

An electrically insulating washer 23 retains the rivet 19 spaced from electrical contact with the covcr 16. The rivet 19 includes a protrusion 25 which will be discussed more fully hereinafter. lerminal issenibly 13 is constructed in an inaloguous manner to that of terminal assembly 14 and includes a rivet 26 projecting through aperture 27 in the wall 16. an external terminal end '.8 suitable attachcd to the end of shank 29. in electric 'illy insulating WIS11Cl- 3() retaining the rivet 26 in spaccd relitionship from electrical contact with wall 16, and a protrusion 32.

Terminal assembly 12 and terminal assemblv 13 are further retained in place by electrically insulating means 33.

An apertured. non-flexible member 34 is located adjacent to the wall 16. The area of the member 34 is substantially the same as the cross-sectional area of the housing Ii adjacent the wall 16. The member 34 as well as the wall 16 may be oval, circular, rectangular or square. As shown in Figure 1, the member 34 includes a peripheral reinforcing rib 35 which engages or contacts the periphery of the wall 16 adjacent edge 18 of the housing 11. The rib 35 reinforces and thereby helps to render the member 34 non-flexible. Figure 3 is a side view of the non-flexible member 34 illustrated in Figure 1 of the drawing.An appropriate network (not shown) of additional reinforcing means or ribs 35 mav be formed in the member 34 and/or the member may be of suitable thickness so as to further help minimize any tendencv of the member to flex in any direction. Member 34 is fabricated from any suitable non-flexible and electrically insulatino material such as glass rcinforced polyamide. or a phenolformaldehyde rcsin, or the like.

Again referring to Figure 1. apertures 37 and 38 are formed in member 34. Each of the apertures 37 and 38 has the same shape as. but a cross-sectional area that is slightly greater than. that of the respective protrusions (either 25 or 32 as the case may bc) of the respective terminal assemblies (either 12 or 13 as the case mnv be). Each of the protrusions projects through its respective aperture in member 34 and extends a very short distance bevond the member 34 in the direction toward the capacitor electrical component 14.

Anode connection element 39. a resilient metallic lead or tab strip suitablv attached to and extending from the anode foil (not shown) of the capacitor electrical component 14. is in contact with the end of the protrusion 25 extending through the aperture 37 and slightly bevond the adjacent surface 41 of the non-flexible member 34.

Cathode connection element 40. a resilient metallic lead or tab strip suitably attached to and extending from the cathode foil (not shown) of the capacitor electrical component 14. is in contact with the end of the protrusion 32 extending through the aperture 3X and slightly bevond the adjacent surface 41 of the non-flexible member 34. If desired. the connection elements 39 and 40 may be connected to their respective protrusions 37. 38 bv means of rupturable bond formed bv for example welding.As illustrated in Figure 1 . each of the connection elements 39 and 4() is shaped at least adjacent the aperture formed in member 34 so that neither of the connections 39and 40 is able to freely move into its adjacent aperture. This is achieved as shown in the several Figures of the drawings by the width of a tab strip 39 and 40 being greater than the largest dimension of its associated aperture 37 and 38.

Upon doming of the wall 16 due to the generation or evolution of fluid within the housing 11, protrusion 25 or protrusion 32 or both are displaced relative to the nonflexible member 34 allowing the anode connection element 39 and/or the cathode connection element 40 to flex resiliently and engage with adjacent surface 41 of the non-flexible member 34. Further doming of the wall 16 causes further displacement of one or both of the protrusions 25 and 32 relative to the non-flexible member 34 and the connection elements 39 and 40. Such displacement of one or both of the protrusions 25 and 32 relative to the non-flexible member 34 and the connection elements 39 and 40 causes either one or both of the connection elements to become electrically uncoupled from its heretofore electrically associated protrusion thereby rendering the electrical device 10 inoperative.Figure 2 of the drawing shows protrusions 25 and 32 electrically separated from the anode and cathode connection elements 39 and 40 respectively. The electrically insulating, non-flexible member 34 thereafter avoid the possibility of electrical reconnection being made between the protrusions 25 and/or 32 and anode and/or cathode connection elements 39 and 40 (as the case may be). by blocking resilient movement of the connection elements 39. 40 towards the wall 16.

Referring now to Figure 4 of the drawing.

a three terminal electrical device 50 is shown. The three terminal electrical device 50 includes a housing 11. terminal assemblies 12. 13 and 51, two electrical components (not shown) having an electrically common cathode connection element 40 and anode connection elements 39 and 52, and a dielectric liquid (not shown) in the housing and contacting each of the electrical components. Each of the electrical components (not shown) may be a convolutely wound capacitor roll of the type described hereinbefore in the discussion of Figure 1.

Each of the terminal assemblies 12. 13 and jl is constructed in an analoguous manner and as described in the description of terminal assemblies 12 and 13 shown in Figures I and 2.

The non-flexible member 34 of Figures 4 and 5 of the drawing includes an appropriate network of reinforcing means or ribs 35 formed therein SO as to further help minimize any tendencv of the member to flex in any direction. In addition to apertures 37 and 38. the member 34. as shown in Figures 4 and 5, includes a third aperture 53 to accommodate protrusion 54 of terminal assembly 51. Anode connection element 52 is bonded to the end of protrusion 54 extending through aperture 53. Electrically insulating washer 55 retains the terminal assembly 51 in spaced relationship from electrical contact with wall 16.

Upon doming the wall 16, protrusion 25, or protrusion 32, or protrusion 54, or any two protrusions, or all protrusions are displaced relative to the non-flexible member causing the anode connection element 39 and/or the cathode connection element 40 and/or the anode connection element 52 to engage with adjacent surface 41 of the non-flexible member 34. Further doming of the wall 16 causes further displacement of one or more of the protrusions relative to the non-flexible member and the connection elements 39, 40 and 52.Such displacement of one or more of the protrusions 25, 32 and 54 relative to the non-flexible member 34 and the connection elements 39. 40 and 52 causes one or more of the connection elements to become electrically uncoupled from its heretofore electrically associated protrusion in the manner as discussed in Figures 1 and 2 of the drawing thereby rendering the electrical device 50 inoperative. The electrically insulating. non-flexible member 34 thereafter avoids the possibility of electrical reconnection between a protrusion and the anode and cathode connection elements by preventing resilient flexure of these towards the wall 16. When using a three terminal device shown in Figure 4, it is desirable that at least two protrusions separate from their cooperatively associated connection elements so that the electrical device is inoperative thereafter across any combination of terminals.

The term "electrical device" as used herein means and includes, but is not limited to. any electrical device adapted for storing electrical energy such as a capacitor as well as any-electrical device adapted for discharge of electrical energy by an electrochemical reaction between positive and negative electrodes such as a battery.

The term "fluid" as used herein means and includes. but is not limited to, gases and liquids.

WHAT WE CLAIM IS: 1. An electrical device comprising a housing having a wall carrying an electrical terminal. an electrical component with anode and cathode connection elements within the housing. an apertured nonflexible member disposed between the electrical component and the said wall of the housing. a part of the electrical terminal extending freely through an aperture in the non-flexible member the cross sectional area of which aperture is greater than that of

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (9)

1. **WARNING** start of CLMS field may overlap end of DESC **.

   so that neither of the connections 39and 40 is able to freely move into its adjacent aperture. This is achieved as shown in the several Figures of the drawings by the width of a tab strip 39 and 40 being greater than the largest dimension of its associated aperture 37 and 38.

   Upon doming of the wall 16 due to the generation or evolution of fluid within the housing 11, protrusion 25 or protrusion 32 or both are displaced relative to the nonflexible member 34 allowing the anode connection element 39 and/or the cathode connection element 40 to flex resiliently and engage with adjacent surface 41 of the non-flexible member 34. Further doming of the wall 16 causes further displacement of one or both of the protrusions 25 and 32 relative to the non-flexible member 34 and the connection elements 39 and 40. Such displacement of one or both of the protrusions 25 and 32 relative to the non-flexible member 34 and the connection elements 39 and 40 causes either one or both of the connection elements to become electrically uncoupled from its heretofore electrically associated protrusion thereby rendering the electrical device 10 inoperative.Figure 2 of the drawing shows protrusions 25 and 32 electrically separated from the anode and cathode connection elements 39 and 40 respectively. The electrically insulating, non-flexible member 34 thereafter avoid the possibility of electrical reconnection being made between the protrusions 25 and/or 32 and anode and/or cathode connection elements 39 and 40 (as the case may be). by blocking resilient movement of the connection elements 39. 40 towards the wall 16.

   Referring now to Figure 4 of the drawing.

   a three terminal electrical device 50 is shown. The three terminal electrical device 50 includes a housing 11. terminal assemblies 12. 13 and 51, two electrical components (not shown) having an electrically common cathode connection element 40 and anode connection elements 39 and 52, and a dielectric liquid (not shown) in the housing and contacting each of the electrical components. Each of the electrical components (not shown) may be a convolutely wound capacitor roll of the type described hereinbefore in the discussion of Figure 1.

   Each of the terminal assemblies 12. 13 and jl is constructed in an analoguous manner and as described in the description of terminal assemblies 12 and 13 shown in Figures I and 2.

   The non-flexible member 34 of Figures 4 and 5 of the drawing includes an appropriate network of reinforcing means or ribs 35 formed therein SO as to further help minimize any tendencv of the member to flex in any direction. In addition to apertures 37 and 38. the member 34. as shown in Figures 4 and 5, includes a third aperture 53 to accommodate protrusion 54 of terminal assembly 51. Anode connection element 52 is bonded to the end of protrusion 54 extending through aperture 53. Electrically insulating washer 55 retains the terminal assembly 51 in spaced relationship from electrical contact with wall 16.

   Upon doming the wall 16, protrusion 25, or protrusion 32, or protrusion 54, or any two protrusions, or all protrusions are displaced relative to the non-flexible member causing the anode connection element 39 and/or the cathode connection element 40 and/or the anode connection element 52 to engage with adjacent surface 41 of the non-flexible member 34. Further doming of the wall 16 causes further displacement of one or more of the protrusions relative to the non-flexible member and the connection elements 39, 40 and 52.Such displacement of one or more of the protrusions 25, 32 and 54 relative to the non-flexible member 34 and the connection elements 39. 40 and 52 causes one or more of the connection elements to become electrically uncoupled from its heretofore electrically associated protrusion in the manner as discussed in Figures 1 and 2 of the drawing thereby rendering the electrical device 50 inoperative. The electrically insulating. non-flexible member 34 thereafter avoids the possibility of electrical reconnection between a protrusion and the anode and cathode connection elements by preventing resilient flexure of these towards the wall 16. When using a three terminal device shown in Figure 4, it is desirable that at least two protrusions separate from their cooperatively associated connection elements so that the electrical device is inoperative thereafter across any combination of terminals.

   The term "electrical device" as used herein means and includes, but is not limited to. any electrical device adapted for storing electrical energy such as a capacitor as well as any-electrical device adapted for discharge of electrical energy by an electrochemical reaction between positive and negative electrodes such as a battery.

   The term "fluid" as used herein means and includes. but is not limited to, gases and liquids.

   WHAT WE CLAIM IS: 1. An electrical device comprising a housing having a wall carrying an electrical terminal. an electrical component with anode and cathode connection elements within the housing. an apertured nonflexible member disposed between the electrical component and the said wall of the housing. a part of the electrical terminal extending freely through an aperture in the non-flexible member the cross sectional area of which aperture is greater than that of

   the said part of the terminal, which latter is in electrical contact with one of the connection elements at a location between the said non-flexible member and the said electrical component, this connecting element having such a configuration in relation to the aperture of the non-flexible member that displacement of the terminal relative to the non-flexible member in a direction away from the said electrical device causes the connection element and the electrical ter minal to become electrically uncoupled rendering the electrical device inoperative.
2. 2. An electrical device according to claim I, wherein the said connection elements are resilient and the non-flexible member prevents resilient movement of the connection elements from re-establishing electrical connection between the connection elements and the terminal after uncoupling displacement of the terminal has occurred.
3. 3. An electrical device according to claim I or 2, wherein the non-flexible member includes reinforcing means to reinforce the non-flexible member against flexing.
4. 4. An electrical device according to claim 3. wherein the reinforcing means are rib means.
5. 5. An electrical device according to any of the preceding claims. wherein the said part of the electrical terminal is a protrusion extending through the aperture in the nonflexible member and electrically connected to one of the electrical connection elements.
6. 6. An electrical device according to claim 5. wherein the configuration and resilience of the connection elements causes engagement of the connection elements with the non-flexible member upon displacement of the protrusion relative to the non-flexible member.
7. 7. An electrical device according to claim 6. wherein the protrusion is an elongate cylinder. the connection element is a curved resilient strip and the aperture is an elongate cylinder.
8. 8. An electrical device according to any of the preceding claims. wherein the device is adapted for storage of electrical energv.
9. 9. An electrical device according to any of the preceding claims. wherein the device is a capacitor, 1(). A capacitor according to claim 9.

   wherein the capacitor includes a liquid dielectric.

   I I . All electrical device substantially as hcrcinbcfoie described with reference to the accompanying driwings.