1. Apparatus for detecting a discontinuity within a non-biological element located within a biological structure, the apparatus comprising:
a microwave energy source;
a first antenna coupled to the microwave energy source and arranged to transmit the microwave energy into the biological structure;
a second antenna arranged to receive at least a portion of the transmitted microwave energy;
an antenna carrier arranged to have the first and second antenna affixed thereon and including means for moving the first and second antenna with respect to the biological structure; and
a signal processing unit coupled to the second antenna and arranged to determine the phase andor magnitude response of the received microwave energy as a function of the position of the antennas with respect to the biological structure and provide an indication of the location of the discontinuity within the non-biological element according to the phase andor magnitude response.
2. Apparatus according to claim 1, wherein the signal processing unit is arranged to determine the phase andor magnitude response of the received microwave energy corresponding to a plurality of positions of the antenna relative to the biological structure and to process the determined phase andor magnitude responses to generate image data of the discontinuity.
3. Apparatus according to claim 2, wherein the signal processing unit is arranged to apply scanning radar techniques to generate the image data.
4. Apparatus according to claim 1, wherein the first antenna is also arranged to receive at least a portion of the transmitted microwave energy and the second antenna is also coupled to the microwave energy source and arranged to transmit the microwave energy into the biological structure.
5. Apparatus according to claim 1, wherein the signal processing unit is arranged to determine the phase andor magnitude response of the microwave energy transmitted from one antenna to the other and the phase andor magnitude response of the microwave energy reflected back to the same antenna it was transmitted from.
6. Apparatus according to claim 1, wherein the location of the discontinuity is given by the relative position of the antennas and the biological structure where a peak or null in the magnitude response of the received microwave energy is detected.
7. Apparatus according to claim 1 further comprising a plurality of microwave energy sources and switching means for selecting one or more of the plurality of microwave energy sources.
8. Apparatus according to claim 7, wherein the plurality of microwave energy sources are arranged to generate microwave energy at different frequencies.
9. Apparatus according to claim 1, wherein the microwave energy source is arranged to generate microwave energy across a plurality of frequencies.
10. Apparatus according to claim 9, wherein the microwave energy source comprises an impulse system.
11. Apparatus according to claim 1, wherein the signal processor is arranged to perform two port transmission and reflection measurements of the microwave energy.
12. Apparatus according to claim 1, wherein the discontinuity comprises a cylindrical hole and the microwave energy source is arranged to generate the microwave energy at a frequency or range of frequencies at which the wavelength of the microwave energy propagated through biological structure and discontinuity is such that the cylindrical hole functions as a cylindrical waveguide.
13. Apparatus according to claim 12, wherein the apparatus further comprises a dielectric loading element arranged to be inserted within the discontinuity.
14. Apparatus according to claim 13, wherein the dielectric loading element has a relative permittivity substantially equal to or greater than the surrounding biological structure.
15. Apparatus according to claim 1, wherein the microwave energy source is arranged to generate the microwave energy in a pulsed mode.
16. Apparatus according to claim 1, wherein at least one of the first and second antennas comprises a helical antenna arranged to be inserted within the biological structure.
17. Apparatus according to claim 16, wherein at least a portion of the helical antenna is mounted within a guide tube, the guide tube being made from a biocompatible material.
18. Apparatus according to claim 17, wherein the helical antenna comprises a helical winding, the winding being located within the guide tube.
19. A method of detecting a discontinuity within a non-biological element located within a biological structure, the method comprising:
transmitting microwave energy into the biological structure from a first antenna;
receiving at least a portion of the transmitted microwave energy at a second antenna;
moving the first and second antenna with respect to the biological structure; and
measuring the received microwave energy and determining the phase andor magnitude response of the received microwave energy as a function of the position of the antennas with respect to the biological structure and providing an indication of the location of the discontinuity within the non-biological element according to the phase andor magnitude response.
20. The method of claim 19, wherein the phase andor magnitude response of the received microwave energy is determined at a plurality of positions of the antenna relative to the biological structure and are processed to generate image data of the discontinuity.
21. The method of claim 20, wherein the image data is generated by apply scanning radar techniques.
22. The method of claim 19, wherein at least a portion of the transmitted microwave energy is also received at the first antenna and at least a portion of the transmitted microwave energy is also transmitted from the second antenna.
23. The method of claim 19, wherein the determined phase andor magnitude response includes the phase andor magnitude response of the microwave energy transmitted from one antenna to the other and the phase andor magnitude response of the microwave energy reflected back to the same antenna it was transmitted from.
24. The method of claim 19, wherein the location of the discontinuity is given by the relative position of the antennas and the biological structure where a peak or null in the magnitude response of the received microwave energy is detected.
25. The method of claim 19 further comprising selecting one or more of a plurality of microwave energy sources for transmission into the biological structure.
26. The method of claim 25, wherein the plurality of microwave energy sources generate microwave energy at different frequencies.
27. The method of claim 19, wherein the microwave energy is generated across a plurality of frequencies.
28. The method of claim 27, wherein the microwave energy is generated by an impulse system.
29. The method of claim 19 further comprising performing two port transmission and reflection measurements of the microwave energy.
30. The method of claim 19, wherein the discontinuity comprises a cylindrical hole and the method further comprises loading the hole with a dielectric loading element.
31. The method of claim 30, wherein the dielectric loading element has a relative permittivity substantially equal to or greater than the surrounding biological structure.
32. The method of claim 19, wherein the microwave energy is generated in a pulsed mode.
33. The method of claim 19, wherein at least one of the first and second antennas comprises a helical antenna inserted within the biological structure.
34. The method of claim 33, wherein at least a portion of the helical antenna is mounted within a guide tube, the guide tube being made from a biocompatible material.
35. The method of claim 19, wherein the non-biological element comprises an intramedullary nail and the discontinuity comprises a locking hole within the nail.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A belt retractor comprising
a frame (10),
a belt spool (12) that is rotatably mounted in said frame (10), and
a force limiter (22) that is adapted to reach a force limiting position,
a guide-in mechanism (26) being provided which causes said force limiter (22) to reach said force limiting position as a function of the length of belt webbing withdrawn.
2. The belt retractor according to claim 1, wherein said force limiter is a cutting body (22) that cuts material in said force limiting position.
3. The belt retractor according to claim 1, wherein a control pin (24) is provided, said control pin (24) being part of said guide-in mechanism (26).
4. The belt retractor according to claim 1, wherein a gearwheel (30) is provided on said frame (10).
5. The belt retractor according to claim 4, wherein a projection (28) is provided, said projection (28) being part of said belt spool (12) and said projection (28) meshing with said gearwheel (30).
6. The belt retractor according to claim 4, wherein a lever (34) is provided that is mounted at said belt spool (12).
7. The belt retractor according to claim 6, wherein a longer tooth (32) and a lever (34) are provided, said gearwheel (30) having said longer tooth (32) which can actuate said lever (34).
8. The belt retractor according to claim 4, wherein a spring-elastic member (36) is provided that urges said control pin (24) into an initial position.
9. The belt retractor according to claim 1, wherein a drive dog (38) is provided that is stationarily mounted at said frame (10).
10. The belt retractor according to claim 9, wherein teeth (46), a transmission gearing (40), an input gear (42) and an output gear (44) are provided, said control pin (24) having said teeth (46) and said transmission gearing (40) having said input gear (42) and said output gear (44) and said output gear (44) engaging said teeth (46).
11. The belt retractor according to claim 1, wherein a projection (54) is provided, said frame (10) having said projection (54) adapted to engage said control pin (24).
12. The belt retractor according to claim 11, wherein a lug (50) and a disc (16) is provided and said disc (16) has an opening (48), said control pin (24) having said lug (50) fitted thereto, which can move through said opening (48) of said disk (16).
13. The belt retractor according to claim 11, wherein a spring-elastic member (56) is provided that adjusts said control pin (24) axially.
14. The belt retractor according to claim 1, wherein a rope (60) and a rope pulley (58) are provided at said frame (10), said rope (60) being adapted to be wound up on and withdrawn from said rope pulley (58).
15. The belt retractor according to claim 14, wherein said rope (60) is connected with said control pin (24).
16. The belt retractor according to claim 1, wherein a member (64) is provided that rests on said belt webbing (13) and is adjustable radially in relation to said belt spool (12).
17. The belt retractor according to claim 16, wherein a plate (68) is provided which is adjustable axially in relation to said belt spool (12) and which can engage said control pin (24).
18. The belt retractor according to claim 1, wherein an intermediate disk (78) is provided that is axially displaceable.
19. The belt retractor according to claim 1, wherein a planetary gear having a ring gear (72) and a planet wheel (70) are provided.
20. The belt retractor according to claim 19, wherein a child safety mechanism is provided, said planetary gear being part of said child safety mechanism.
21. The belt retractor according to claim 19, wherein an elevated portion (74) is provided, said ring gear (72) having said elevated portion (74).
22. The belt retractor according to claim 18, wherein an elevated portion (76) is provided, said intermediate disk (78) having said elevated portion (76) that is adapted for alignment with said elevated portion (76) of said ring gear (72).
23. The belt retractor according to claim 18, wherein a magnet (80) and an iron core (82) are provided, said ring gear (72) including said magnet (80) and said intermediate disk (78) including said iron core (82).
24. The belt retractor according to claim 23, wherein an inclined plane (84) is provided on said frame (10).
25. The belt retractor according to claim 19, wherein a coupling disk (86) is provided which is coupled to said ring gear (72).
26. The belt retractor according to claim 25, wherein balls (92) are provided which are arranged between said coupling disk (86) and said intermediate disk (78).
27. The belt retractor according to claim 25, wherein an inclined plane (84) is provided, said intermediate disk (78) including at least one section having said inclined plane (84).
28. The belt retractor according to claim 19, wherein at least one lever (96) is provided which is adapted to engage said control pin (24).
29. The belt retractor according to claim 28, wherein an inclined plane (104) is provided, said at least one lever (96) having said inclined plane (104).
30. The belt retractor according to claim 19, wherein a lever (106) is provided.
31. The belt retractor according to claim 1, wherein a reduction gear is provided having a reduction gearwheel (110) and a switching fork (117).
32. The belt retractor according to claim 31, wherein a switching rocker (118) is provided which is shifted rotationally by said switching fork (117).
33. The belt retractor according to claim 31, wherein a switching lever (119) is provided which is shifted translationally by said switching fork (117).