CA1256916A - Beacon activation device - Google Patents
Beacon activation deviceInfo
- Publication number
- CA1256916A CA1256916A CA000498589A CA498589A CA1256916A CA 1256916 A CA1256916 A CA 1256916A CA 000498589 A CA000498589 A CA 000498589A CA 498589 A CA498589 A CA 498589A CA 1256916 A CA1256916 A CA 1256916A
- Authority
- CA
- Canada
- Prior art keywords
- battery
- switch
- aircraft
- transmitter
- outer tube
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Abstract
ABSTRACT
An aircraft crash position indicator with an improved radio beacon activation device. An emergency transmitter deVice comprises a radio transmitter, a battery, and a deformable normally open switch connected electrically between the battery and an activation switch. The device is releasably mounted on an airframe, with the deformable normally open switch co-acting with an ejector device so that operation of the ejector device causes release of the emergency transmitter device from the airframe and at the same time permanently deforms the normally open switch into a closed position thereby to energize the transmitter from the battery. The normally open switch comprises a permanently deformable conductive outer tube within which a central conductor is co-axially disposed and electrically insulated therefrom.
Deformation of the outer conductive tube establishes permanent electrical connection with the central conductor and closes the circuit between the transmitter and the battery.
An aircraft crash position indicator with an improved radio beacon activation device. An emergency transmitter deVice comprises a radio transmitter, a battery, and a deformable normally open switch connected electrically between the battery and an activation switch. The device is releasably mounted on an airframe, with the deformable normally open switch co-acting with an ejector device so that operation of the ejector device causes release of the emergency transmitter device from the airframe and at the same time permanently deforms the normally open switch into a closed position thereby to energize the transmitter from the battery. The normally open switch comprises a permanently deformable conductive outer tube within which a central conductor is co-axially disposed and electrically insulated therefrom.
Deformation of the outer conductive tube establishes permanent electrical connection with the central conductor and closes the circuit between the transmitter and the battery.
Description
~,25~6 6292-~3 This invention relates to aircraft emergency radio beacons generally known as crash position indicators (CPI's) which are intended to transmit distress signals only upon crashing of the aircraft.
Such CPI's which are designed to deploy from the body of an aircraft while it is crashing and begin transmitting automatic-ally more or less simultaneously with the deployment, have hereto-fore contained activation systems electrically biased-on to trans-mit downed aircraft distress signals over the International Guard Frequency (IGF) for the purpose of location and rescue.
Auxiliary batteries generally called shut-off batteries mounted in the airframe have heretofore been required to counter-balance the electrical biasing-on of transmitters in CPI's and hold the transmitter shut off until, in the event of a crash, an ejector mechanism known as an airEoil release unit, (ARU~, ejects`
the CPI from the airframe thereby breaking the connection to the shut-off battery and allowing the transmitter to operate.
Auxiliary batteries generally called ground shut-off batteries supplied as ground support equipment have heretofore been required to counterbalance the electrical on-biasing of the CPI transmitter when the CPI was being installed, removed, or serviced. An alternative to ground shut-off batteries has been to provide a manual shut-off switch in the CPI.
CPI's used heretofore have been reliable in activation of the beacon but have shown poor reliability in holding the beacon in a deactivated position. Human error in attaching the ground shut-off battery during removal, servicing, a`nd installa-- 1 - ~' ~.25~
tion of the CPI, negligence in turning ofE the manual shut-off switch, as well as drainage o~ the ground shut-off battery can cause the CPI to transmit. Drainage of the airframe mounted shut-off battery due to exceeding of battery recharging intervals, battery exhaustion, electrical connection failure, failure in charging systems, or failure of the manual shut-off switch can cause the CPI to transmit.
The transmission of distress signals over the IGF other than for short test transmissions is illeyal except in an emer-gency situation and also causes battery drainage.
It is an object of this invention to provide a CPI thatis as reliable as existing systems in its activation but also very reliable in holding the beacon in a de-activated mode during flight and ground servicing.
It is a further object of this invention to provide a CPI that does not require a ground shut-off battery or manual switch to hold it in the off position, greatly reducing the factor of human error in its installation and maintenance.
It is a still further object of this invention to pro-vide a CPI that does not require an auxiliary battery mounted inthe airframe, thereby reducing the complexity and probability of malfunction of the system and also resulting in a saving of weight and space in the airframe~
The present invention provides, in accordance with a first broad aspect, an emergency transmitter device comprising a radio transmitter, a battery, and a normally open switch means electrically connected between the battery and the transmitter, the device having mounting means for releasably attaching the 5~
device to an aircraft and co-acting with ejector means on the aircraft such that that operation of the ejector means causes release of the device from the aircraft, the switch means being positioned such that, when the device is attached to the aircraft and the ejector means operates, the ejector means ac-tivates the switching means es~ablishing permanent electrical connection thereby energizing the transmitter from the battery.
According to another broad aspect, the present invention provides an emergency transmitter device comprising a radio trans-mitter, a battery, and a deformable normally open switching means connected electrically between the battery and the transmit~er, the device having mounting means for releasably attaching the device to an aircraft, and co-acting with ejector means on the aircraft such that operation of the ejector means causes release of the device from the aircraft, the switch means being positioned such that, when the device is attached to the aircraft and the ejector means operates, the ejector means permanen~ly deforms the switch means into a closed position thereb~ energizing the trans-mitter from the battery.
The foregoing and other features of the invention are illustrated in the accompanying drawings in which:
Figure 1 is an isometric view of a typical deployable CPI during release from the airframe;
Figure 2 is a cross-sectional view to an enlarged scale of the CPI of Figure 1 during release from the airframe;
Figure 3 is a cross-sec-tional view oE an embodiment of the ARU before release;
Fig~re 4 is a view similar to Figure 3 but showing the ARU during releas~;
Figure 5 i5 a cross-sectional view of an installed deployment sensor switch before release;
Figure 6 is a cross-sectional view of an installed deployment sensor switch during release;
Fiyure 7 is an isometric cut-away view of an uninstalled deployment switch.
Referring to Figure 1, a typical mounting arrangement during release is disclosed. The CPI 1 is positioned in a cut-out or indentation in the exterior skin 2 of an aircraft in such a way that the top surface 5 of the CPI 1 more or less conforms to the aerodynamic shape of the exterior skin 2 of the aircraft. During release, a cylinder and pressure housing assembly 3 of an ARU
disengages from a retainer assembly 4 of the CPI, the ARU being positioned near the leading edge of the CPI 1 in relation to the airstream, allowing the airstream to lift the CPI away from the airframe.
Referring to Figure 2, an embodiment of a CPI 1 in which is contained a transmitter 7, a transmitter battery 8, and a con-nector 9 electrically connecting the transmitter and battery through a deployment sensor switch 10 which is normally open, thus preventing the transmitter from being energized, is shown. The ARU assembly 11 is shown in released position with the retainer assembly 4 disengaged ~rom the cylinder and pressure housing assembly 3. The CPI 1 before release is held in position at the trailing edge of ~he CPI by a hook 14 or like means releasably engaged in a bracket 6 or similar fitting on the airframe and by the ARU 11 engaging retainer assembly 4 so that the top of the CPI more or less conforms to the aerodynamic shape of the aircraft outer skin 2. For illustrative purposes, the deployment se~sor switch 10 is shown in non-deformed condition.
Referring to Figure 3, a cross sectional view of an embodiment of an AR~ before release is shown in more detail. The retainer assembly 4 is attached fixedly to the leading edge of CPI 1 by bolts 22 or like means, while the cylinder and pressure housing assembly 3 is similarly attached by bolts 22 or like means to a section of the airframe 21 or some stanchion or bracket fixedly attached thereto. The cylinder 13 is fixedly attached to the pressure housing 23, and fitted with a pressure cartridge 24.
A piston 27, comprising a lower portion 2B, a portion of reduced diameter 16 and a crown 17 is co-axially disposed within the cylinder 13. The retainer assembly 4, retained onto the ARU by one or more retaining balls 15 slidably inserted in one or more ball races lB, is fitted with the deployment sensor switch 10 transversely disposed through a diameter within the retaining assembly 4. Before release, the retaining assembly 4 is held together with the cylinder 13 by means of the retaining balls 15 abutting against a cam 19 which is circumferentially shaped around the inner portion of retainer assembly 4 and abutting also against the crown 17 of piston 27.
Referring to Figures 3 and 4, the pressure cartridge 24 is electrically connected by cable 25 to an inertia or contact switch (not shown) of several varieties currently in the art which are suitable. In the event oE a crash, an electrical signal fires the pressure cartridge 24, which pressurizes a plenum chamber 40 ~ 25~
below the lower portion of piston 28 by means of a duct 26 within pressure housing 23, driving the piston 27 upward within cylinder 13.
Referring to ~igure 4, the initial upward movement of piston 27 allows the portion of reduced diameter 16 of the piston 27 to be disposed against ball race 18, the further upward move-ment of the piston 27 causing the crown 17 permanently to deform deployment sensor switch 10. The further upward movement of the piston 27 urges upward against the retaining assembly 4, causing the cam 19 to displace the retaining balls 15 inwardly in relation to the cylinder 13, the balls sliding into the portion of reduced diameter 16 of piston 27, allowing the retaining assembly 4 to disengage from the cylinder 13. The further upward movement of the piston urges the leading edge of the CPI to be inserted into the position indicated in Figures 1 and 2.
Referring generally to Figure 4, and specifically to Figures 5, 6 and 7, the deployment sensor switch is comprised of two metallic elements preferably of copper, namely an outer con-ductive tube 36 and a central conductor 35 co-axially disposed
Such CPI's which are designed to deploy from the body of an aircraft while it is crashing and begin transmitting automatic-ally more or less simultaneously with the deployment, have hereto-fore contained activation systems electrically biased-on to trans-mit downed aircraft distress signals over the International Guard Frequency (IGF) for the purpose of location and rescue.
Auxiliary batteries generally called shut-off batteries mounted in the airframe have heretofore been required to counter-balance the electrical biasing-on of transmitters in CPI's and hold the transmitter shut off until, in the event of a crash, an ejector mechanism known as an airEoil release unit, (ARU~, ejects`
the CPI from the airframe thereby breaking the connection to the shut-off battery and allowing the transmitter to operate.
Auxiliary batteries generally called ground shut-off batteries supplied as ground support equipment have heretofore been required to counterbalance the electrical on-biasing of the CPI transmitter when the CPI was being installed, removed, or serviced. An alternative to ground shut-off batteries has been to provide a manual shut-off switch in the CPI.
CPI's used heretofore have been reliable in activation of the beacon but have shown poor reliability in holding the beacon in a deactivated position. Human error in attaching the ground shut-off battery during removal, servicing, a`nd installa-- 1 - ~' ~.25~
tion of the CPI, negligence in turning ofE the manual shut-off switch, as well as drainage o~ the ground shut-off battery can cause the CPI to transmit. Drainage of the airframe mounted shut-off battery due to exceeding of battery recharging intervals, battery exhaustion, electrical connection failure, failure in charging systems, or failure of the manual shut-off switch can cause the CPI to transmit.
The transmission of distress signals over the IGF other than for short test transmissions is illeyal except in an emer-gency situation and also causes battery drainage.
It is an object of this invention to provide a CPI thatis as reliable as existing systems in its activation but also very reliable in holding the beacon in a de-activated mode during flight and ground servicing.
It is a further object of this invention to provide a CPI that does not require a ground shut-off battery or manual switch to hold it in the off position, greatly reducing the factor of human error in its installation and maintenance.
It is a still further object of this invention to pro-vide a CPI that does not require an auxiliary battery mounted inthe airframe, thereby reducing the complexity and probability of malfunction of the system and also resulting in a saving of weight and space in the airframe~
The present invention provides, in accordance with a first broad aspect, an emergency transmitter device comprising a radio transmitter, a battery, and a normally open switch means electrically connected between the battery and the transmitter, the device having mounting means for releasably attaching the 5~
device to an aircraft and co-acting with ejector means on the aircraft such that that operation of the ejector means causes release of the device from the aircraft, the switch means being positioned such that, when the device is attached to the aircraft and the ejector means operates, the ejector means ac-tivates the switching means es~ablishing permanent electrical connection thereby energizing the transmitter from the battery.
According to another broad aspect, the present invention provides an emergency transmitter device comprising a radio trans-mitter, a battery, and a deformable normally open switching means connected electrically between the battery and the transmit~er, the device having mounting means for releasably attaching the device to an aircraft, and co-acting with ejector means on the aircraft such that operation of the ejector means causes release of the device from the aircraft, the switch means being positioned such that, when the device is attached to the aircraft and the ejector means operates, the ejector means permanen~ly deforms the switch means into a closed position thereb~ energizing the trans-mitter from the battery.
The foregoing and other features of the invention are illustrated in the accompanying drawings in which:
Figure 1 is an isometric view of a typical deployable CPI during release from the airframe;
Figure 2 is a cross-sectional view to an enlarged scale of the CPI of Figure 1 during release from the airframe;
Figure 3 is a cross-sec-tional view oE an embodiment of the ARU before release;
Fig~re 4 is a view similar to Figure 3 but showing the ARU during releas~;
Figure 5 i5 a cross-sectional view of an installed deployment sensor switch before release;
Figure 6 is a cross-sectional view of an installed deployment sensor switch during release;
Fiyure 7 is an isometric cut-away view of an uninstalled deployment switch.
Referring to Figure 1, a typical mounting arrangement during release is disclosed. The CPI 1 is positioned in a cut-out or indentation in the exterior skin 2 of an aircraft in such a way that the top surface 5 of the CPI 1 more or less conforms to the aerodynamic shape of the exterior skin 2 of the aircraft. During release, a cylinder and pressure housing assembly 3 of an ARU
disengages from a retainer assembly 4 of the CPI, the ARU being positioned near the leading edge of the CPI 1 in relation to the airstream, allowing the airstream to lift the CPI away from the airframe.
Referring to Figure 2, an embodiment of a CPI 1 in which is contained a transmitter 7, a transmitter battery 8, and a con-nector 9 electrically connecting the transmitter and battery through a deployment sensor switch 10 which is normally open, thus preventing the transmitter from being energized, is shown. The ARU assembly 11 is shown in released position with the retainer assembly 4 disengaged ~rom the cylinder and pressure housing assembly 3. The CPI 1 before release is held in position at the trailing edge of ~he CPI by a hook 14 or like means releasably engaged in a bracket 6 or similar fitting on the airframe and by the ARU 11 engaging retainer assembly 4 so that the top of the CPI more or less conforms to the aerodynamic shape of the aircraft outer skin 2. For illustrative purposes, the deployment se~sor switch 10 is shown in non-deformed condition.
Referring to Figure 3, a cross sectional view of an embodiment of an AR~ before release is shown in more detail. The retainer assembly 4 is attached fixedly to the leading edge of CPI 1 by bolts 22 or like means, while the cylinder and pressure housing assembly 3 is similarly attached by bolts 22 or like means to a section of the airframe 21 or some stanchion or bracket fixedly attached thereto. The cylinder 13 is fixedly attached to the pressure housing 23, and fitted with a pressure cartridge 24.
A piston 27, comprising a lower portion 2B, a portion of reduced diameter 16 and a crown 17 is co-axially disposed within the cylinder 13. The retainer assembly 4, retained onto the ARU by one or more retaining balls 15 slidably inserted in one or more ball races lB, is fitted with the deployment sensor switch 10 transversely disposed through a diameter within the retaining assembly 4. Before release, the retaining assembly 4 is held together with the cylinder 13 by means of the retaining balls 15 abutting against a cam 19 which is circumferentially shaped around the inner portion of retainer assembly 4 and abutting also against the crown 17 of piston 27.
Referring to Figures 3 and 4, the pressure cartridge 24 is electrically connected by cable 25 to an inertia or contact switch (not shown) of several varieties currently in the art which are suitable. In the event oE a crash, an electrical signal fires the pressure cartridge 24, which pressurizes a plenum chamber 40 ~ 25~
below the lower portion of piston 28 by means of a duct 26 within pressure housing 23, driving the piston 27 upward within cylinder 13.
Referring to ~igure 4, the initial upward movement of piston 27 allows the portion of reduced diameter 16 of the piston 27 to be disposed against ball race 18, the further upward move-ment of the piston 27 causing the crown 17 permanently to deform deployment sensor switch 10. The further upward movement of the piston 27 urges upward against the retaining assembly 4, causing the cam 19 to displace the retaining balls 15 inwardly in relation to the cylinder 13, the balls sliding into the portion of reduced diameter 16 of piston 27, allowing the retaining assembly 4 to disengage from the cylinder 13. The further upward movement of the piston urges the leading edge of the CPI to be inserted into the position indicated in Figures 1 and 2.
Referring generally to Figure 4, and specifically to Figures 5, 6 and 7, the deployment sensor switch is comprised of two metallic elements preferably of copper, namely an outer con-ductive tube 36 and a central conductor 35 co-axially disposed
2~ within the outer conductive tube 36, electrically insulated from each other by insulating end plugs 37. The deployment sensor switch 10 is encased in a sleeve 39 of aluminum coaxially disposed along the exterior of outer conductive tube 36 which serves to protec~ the deployment sensor switch 10 from mechanical damage, and is electrically isolated ~rom sensor switch 10 by insulating shield 42. Central conductor 35 and outer conductive tube 36 are connected by wires 43 and 44 respectively to the circuit between the transmitter 7 and transmitter battery 8. Wires 43 and 44 are
3~2~
illustrated separately in Figures 5, 6 and 7 for purposes of clarity. Practically, they may form separate elements of a shielded cable. Plugs 37, together with a boot 41 of Elexible insulating material, preferably p]astic, which surrounds the end of switch 10 from which wires 43 and 4~ extend, serve to prevent the ingress of moisture. The upward movement of the piston 27 from the Figure 5 to the Figure 6 position causes the crown 17 to deform the deployment sensor switch 10 so that outer conductive tube 36 and central conductor 35 are permanently in contact with each other, as shown in Figure 6. The deformation shown in Figure 6 is an idealized illustration of the deformation of the deploy-ment sensor switch 10, the practical deformation may be charac-terized by a crushing or crimping deEormation which will cause flattening of the outer conductive tube 36.
The deployment sensor switch 10 need not necessarily be tubular as described, but may assume other forms, for example, the form of a snap-dome which provides momentary electrical contact which can be used with an electrical latching device to provide permanent switch-on.
illustrated separately in Figures 5, 6 and 7 for purposes of clarity. Practically, they may form separate elements of a shielded cable. Plugs 37, together with a boot 41 of Elexible insulating material, preferably p]astic, which surrounds the end of switch 10 from which wires 43 and 4~ extend, serve to prevent the ingress of moisture. The upward movement of the piston 27 from the Figure 5 to the Figure 6 position causes the crown 17 to deform the deployment sensor switch 10 so that outer conductive tube 36 and central conductor 35 are permanently in contact with each other, as shown in Figure 6. The deformation shown in Figure 6 is an idealized illustration of the deformation of the deploy-ment sensor switch 10, the practical deformation may be charac-terized by a crushing or crimping deEormation which will cause flattening of the outer conductive tube 36.
The deployment sensor switch 10 need not necessarily be tubular as described, but may assume other forms, for example, the form of a snap-dome which provides momentary electrical contact which can be used with an electrical latching device to provide permanent switch-on.
Claims (8)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. An emergency transmitter device comprising a radio transmitter, a battery, and a deformable normally open switch means connected electrically between the battery and the trans-mitter, the device having mounting means for releasably attaching the device to an aircraft and co-acting with ejector means on the aircraft such that operation of the ejector means causes release of the device from the aircraft, the switch means being positioned such that, when the device is attached to the aircraft and the ejector means operates, the ejector means permanently deforms the switch means into a closed position thereby to energize the trans-mitter from the battery.
2. An emergency transmitter device according to claim 1 in which the ejector means includes a piston disposed co-axially within a cylinder, a pressure cartridge, and means for firing the cartridge in the event of a crash, the piston engaging the deform-able switch means.
3. An emergency transmitter device according to claim 1 or 2 in which the switch means comprises a deployment sensor switch in the form of a permanently deformable conductive outer tube within which a central inner conductor is co-axially mounted and electrically insulated from the outer tube whereby the ejector means in operation permanently deforms a portion of the outer tube inwardly to sandwich the inner conductor between the deformed portion of the outer tube and an undeformed portion of the outer tube.
4. An emergency transmitter device according to claim 1 in which the switch means comprises a deployment sensor switch in the form of a permanently deformable copper outer tube within which a central inner copper conductor is co-axially mounted and electri-cally insulated from the outer tube whereby the ejector means in operation permanently deforms a portion of the outer tube inwardly to sandwich the inner conductor between the deformed portion of the outer tube and an undeformed portion of the outer tube.
5. An emergency transmitter device as in claim 4, in which the deployment sensor switch is provided with means to prevent the ingress of moisture.
6. An emergency transmitter device as in claim 5, including an aluminum outer sleeve to prevent mechanical damage to the switch, the outer sleeve being insulated from the outer conductive tube by an insulating sleeve.
7. An emergency transmitter device comprising a radio transmitter, a battery, and a normally open switch means electri-cally connected between the battery and the transmitter, the device having mounting means for releasably attaching the device to an aircraft and co-acting with ejector means on the aircraft such that that operation of the ejector means causes release of the device from the aircraft, the switch means being positioned such that, when the device is attached to the aircraft and the ejector means operates, the ejector means activates the switching means establishing permanent electrical connection thereby energizing the transmitter from the battery.
8. An emergency transmitter device according to claim 7, in which the switch means comprises a normally open momentary contact mechanical switch electrically connected to an electrical latching means, whereby the mechanical switch, on engagement by the ejector means, triggers the electrical latch to establish permanent elec-trical contact between the battery and the transmitter.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000498589A CA1256916A (en) | 1985-12-24 | 1985-12-24 | Beacon activation device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000498589A CA1256916A (en) | 1985-12-24 | 1985-12-24 | Beacon activation device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1256916A true CA1256916A (en) | 1989-07-04 |
Family
ID=4132175
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000498589A Expired CA1256916A (en) | 1985-12-24 | 1985-12-24 | Beacon activation device |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1256916A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8706357B1 (en) | 2013-03-14 | 2014-04-22 | Drs C3 & Aviation Company | Flight recorder deployment system and method |
| US9296489B2 (en) | 2013-03-14 | 2016-03-29 | Drs C3 & Aviation Company | Flight recorder deployment mechanism |
-
1985
- 1985-12-24 CA CA000498589A patent/CA1256916A/en not_active Expired
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8706357B1 (en) | 2013-03-14 | 2014-04-22 | Drs C3 & Aviation Company | Flight recorder deployment system and method |
| US9296489B2 (en) | 2013-03-14 | 2016-03-29 | Drs C3 & Aviation Company | Flight recorder deployment mechanism |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |