Separation device for spacecraft and a method for separation
The invention relates to a separation device for a spacecraft or launcher. The separation device includes an inner housing divided into at least two portions locked to each other by a locking device in a locking position. The locking device is arranged to move between a locking position and a releasing position. The separation device includes an initiator including means for providing high pressure fluid to an expansion chamber when the separation device is switched from a locked state to a released state. The high pressure fluid in an expansion chamber moves the locking device from the locking position to the releasing position when the separation device is switched from the locked state to the released state. The separation device includes a dampening arrangement arranged to attenuate a peak load when the separation device is switched from the locked state to the released state.
1. A separation device for a spacecraft or launcher, the separation device comprising:
an inner housing divided into at least two portions locked to each other by a locking device in a locking position and thereby hindering the at least two portions from separating, the locking device is a sleeve configured to engage the inner housing by locking, wherein the locking device is arranged to move between a locking position and a releasing position; and
an initiator comprising means for providing high pressure fluid to an expansion chamber when the separation device is switched from a locked state to a released state, wherein the high pressure fluid in the expansion chamber moves the locking device from the locking position to the releasing position when the separation device is switched from the locked state to the released state, characterized in that the separation device comprises:
a dampening arrangement arranged to attenuate a peak load when the separation device is switched from the locked state to the released state, wherein the dampening arrangement comprises a guiding means arranged to guide the locking device into a rotational movement when the locking device moves from the locking position to the releasing position, and wherein the guiding means comprises a spirally formed recess in the locking device arranged to cooperate with a protrusion arranged in a surrounding housing or wherein the guiding means is a spirally formed recess in the surrounding housing arranged to cooperate with a protrusion arranged in the locking device.
2. The separation device according to claim 1 , wherein the surrounding housing is an outer housing or an intermediate housing between the outer housing and the locking device.
3. The separation device according to claim 1 , wherein the dampening arrangement comprises a dampening plate in an end position in connection to the releasing position, wherein the dampening arrangement comprises at least one dampening pin arranged between the locking device and the dampening plate, wherein the dampening pin is arranged to hit and plastically deform the dampening plate during movement of the locking device from the locking position to the releasing position for absorbing energy from the locking device which attenuates the peak load.
4. The separation device according to claim 3 , wherein the dampening pin comprises a pointy end with an angle that allows for a material in the dampening plate to be pressed at an angle to a travelling direction of the dampening pin.
5. The separation device according to claim 3 , wherein the dampening plate comprises a guiding plate arranged to hold and guide the dampening pin, wherein the locking device is arranged to hit the dampening pin during movement of the locking device from the locking position to the releasing position.
6. The separation device according to claim 3 , wherein the dampening pin is arranged in connection to the locking device, wherein the dampening pin hits the dampening plate during movement of the locking device from the locking position to the releasing position.
7. The separation device according to claim 3 , wherein the separation device comprises an outer housing having an extension in a longitudinal direction and comprising a first end plate covering a first end portion of the outer housing and a second end plate covering a second end portion of the outer housing positioned opposite the first end portion, wherein the second end plate is arranged in connection to the end position, wherein the inner housing is positioned within the outer housing and attached to the second end plate, and wherein the second end plate comprises the dampening plate.
8. The separation device according to claim 7 , wherein the locking device is slidably arranged between the locking position and the releasing position within the outer housing and about the inner housing.
9. The separation device according to claim 7 , wherein the expansion chamber is positioned between the first end plate and the locking device, and wherein the high pressure fluid in the expansion chamber moves the locking device from the locking position to the releasing position in a direction from the first end portion towards the second end portion in the longitudinal direction.
10. The separation device according to claim 1 , wherein the locking device is a sleeve slidably arranged between the locking position and the releasing position.
11. The separation device according to claim 1 , wherein the separation device comprises an ejector slidably arranged between the locking position and the releasing position in a channel within the inner housing, wherein the expansion chamber is arranged to be in fluid communication with the channel.
12. The separation device according to claim 1 , wherein the locking device comprises locking means arranged to engage an inner portion of an outer housing and an outer portion of the inner housing thereby locking the inner housing and hindering separation of the inner housing.
13. The separation device according to claim 3 , wherein the separation device comprises a plurality of dampening pins.
14. The separation device according to claim 1 , wherein the initiator comprises at least two initiator units.
15. The separation device according to claim 14 , wherein the initiator units are arranged to ignite simultaneously.
16. The separation device according to claim 14 , wherein the dampening arrangement comprises a control unit arranged to initiate the initiator units in a sequence with a time interval for shock peak attenuation.
17. The separation device according to claim 1 , wherein the initiator is a pyrotechnic unit.
18. A method for using a separation device, wherein the method comprises the steps of:
initiating an initiator comprising means for providing high pressure fluid to an expansion chamber when the separation device is switched from a locked state to a released state;
moving a locking device from a locking position to a releasing position when the separation device is switched from a locked state to a released state by the high pressure fluid in the expansion chamber; and
attenuating a peak load with a dampening arrangement when the separation device is switched from the locked state to the released state, wherein the dampening arrangement comprises a guiding means and wherein the method comprises the step of the guiding means guiding the locking device into a rotational movement when the locking device moves from the locking position to the releasing position, and wherein the guiding means comprises a spirally formed recess in the locking device arranged to cooperate with a protrusion arranged in a surrounding housing or wherein the guiding means is a spirally formed recess in the surrounding housing arranged to cooperate with a protrusion arranged in the locking device.
19. The method according to claim 18 , wherein the initiator comprises at least two initiator units, and wherein the initiator units are arranged to ignite simultaneously or wherein the initiator units are ignited in sequence with a time interval for shock peak attenuation.