Rotary attenuator and method of making it

Abstract

An attenuator includes a housing defining an interior, a front, a rear, and a rotor mounted between front and rear for rotation within housing about an axis of the rotor. First electrical contacts are provided on the housing. Second electrical contacts are provided on the rotor. The rotor includes multiple printed conductor boards. Each PC board includes an electrically relatively non-conductive substrate. One side of each substrate provides conductive areas through which electrically attenuating elements of the attenuator are coupled together to form an attenuating network providing a selected level of attenuation. Electrical contact is made between the first electrical contacts and the electrically attenuating elements of the attenuator through the second electrical contacts.

1. An attenuator including a housing defining an interior, a rotor mounted for rotation within the housing about an axis of the rotor, first electrical contacts provided on the housing, second electrical contacts being provided on the rotor, and multiple printed conductor (PC) boards for engaging respective second electrical contacts, each PC board including an electrically relatively non-conductive substrate, a first side of each PC board providing electrically relatively conductive areas and electrically relatively non-conductive areas, electrically attenuating elements coupled together in attenuating networks with the electrically relatively conductive areas, the attenuating networks providing selected levels of attenuation, electrical contact being selectively made between the first electrical contacts and selected attenuating networks through the second electrical contacts. 
     
     
       2. The apparatus of  claim 1  wherein the interior is generally right circular cylindrical. 
     
     
       3. The apparatus of  claim 1  further including an index for indicating the position of the rotor within the housing. 
     
     
       4. The apparatus of  claim 1  further including a shaft, the rotor including a passageway for receiving the shaft, the shaft and passageway being provided with complementary features which mate when the shaft is received in the passageway. 
     
     
       5. The apparatus of  claim 1  wherein the housing includes a front closure and a rear closure, at least one of the front closure and rear closure being removably attached to the housing. 
     
     
       6. The apparatus of  claim 1  wherein the rotor includes axially oppositely facing surfaces constructed from electrically relatively non-conductive materials, the second electrical contacts being provided on the axially oppositely facing surfaces. 
     
     
       7. The apparatus of  claim 6  wherein the axially oppositely facing surfaces are surfaces of resin substrates. 
     
     
       8. The apparatus of  claim 6  further including a detent for promoting orientation of the rotor with selected ones of the second electrical contacts in electrical contact with respective ones of the first electrical contacts. 
     
     
       9. The apparatus of  claim 1  further including at least one groove in one of the outer perimeter of the rotor and the interior of the housing, and at least one resilient, electrically relatively conductive contact strip oriented in the groove. 
     
     
       10. The apparatus of  claim 1  wherein each PC board further includes a second side which is electrically relatively conductive, one of the electrically relatively conductive areas on the first side of each PC board being electrically coupled to the second side of that respective PC board. 
     
     
       11. The apparatus of  claim 1  wherein the electrically attenuating elements include surface mount resistors. 
     
     
       12. The apparatus of  claim 1  wherein the electrically attenuating elements of the attenuator are coupled between respective conductive areas. 
     
     
       13. The apparatus of  claim 12  wherein the electrically attenuating elements include surface mount resistors. 
     
     
       14. The apparatus of  claim 1  wherein the rotor includes an outer surface provided with slots which extend generally radially and axially of the outer surface, each slot being wide enough in a circumferential direction around the outer surface of the rotor to receive edgewise a respective one of the PC boards. 
     
     
       15. The apparatus of  claim 14  wherein each PC board further includes an electrically relatively conductive side and further including multiple strips of resilient electrically conductive material, each strip capturing the radially inner edge of a respective PC board and making electrical contact with the electrically relatively conductive side of each PC board, with one of the conductive areas of each PC board, and with the rotor. 
     
     
       16. The apparatus of  claim 14  wherein the electrically relatively non-conductive substrate includes resin. 
     
     
       17. The apparatus of  claim 16  wherein the electrically relatively non-conductive substrate includes fiber reinforced resin. 
     
     
       18. The apparatus of  claim 1  wherein the electrically relatively non-conductive substrate includes fiber reinforced resin. 
     
     
       19. The apparatus of  claim 18  wherein the fiber reinforced resin is fiberglass. 
     
     
       20. The apparatus of  claim 1  wherein the attenuator housing is constructed from extruded aluminum. 
     
     
       21. The apparatus of  claim 1  wherein the attenuator housing is constructed from aluminum tubing. 
     
     
       22. The apparatus of claim 1 wherein the rotor is constructed from zinc.  
     
     
       23. The apparatus of claim 22 wherein the rotor is constructed from die cast zinc.  
     
     
       24. The apparatus of claim 1 wherein the rotor is die cast.  
     
     
       25. The apparatus of claim 2 wherein the rotor is constructed from zinc.  
     
     
       26. The apparatus of claim 25 wherein the rotor is constructed from die cast zinc.  
     
     
       27. The apparatus of claim 2 wherein the rotor is die cast.  
     
     
       28. The apparatus of claim 3 wherein the rotor is constructed from zinc.  
     
     
       29. The apparatus of claim 28 wherein the rotor is constructed from die cast zinc.  
     
     
       30. The apparatus of claim 3 wherein the rotor is die cast.  
     
     
       31. The apparatus of claim 4 wherein the rotor is constructed from zinc.  
     
     
       32. The apparatus of claim 31 wherein the rotor is constructed from die cast zinc.  
     
     
       33. The apparatus of claim 4 wherein the rotor is die cast.  
     
     
       34. The apparatus of claim 5 wherein the rotor is constructed from zinc.  
     
     
       35. The apparatus of claim 34 wherein the rotor is constructed from die cast zinc.  
     
     
       36. The apparatus of claim 5 wherein the rotor is die cast.  
     
     
       37. The apparatus of claim 6 wherein the rotor is constructed from zinc.  
     
     
       38. The apparatus of claim 37 wherein the rotor is constructed from die cast zinc.  
     
     
       39. The apparatus of claim 6 wherein the rotor is die cast.  
     
     
       40. The apparatus of claim 7 wherein the rotor is constructed from zinc.  
     
     
       41. The apparatus of claim 40 wherein the rotor is constructed from die cast zinc.  
     
     
       42. The apparatus of claim 7 wherein the rotor is die cast.  
     
     
       43. The apparatus of claim 8 wherein the rotor is constructed from zinc.  
     
     
       44. The apparatus of claim 43 wherein the rotor is constructed from die cast zinc.  
     
     
       45. The apparatus of claim 8 wherein the rotor is die cast.  
     
     
       46. The apparatus of claim 9 wherein the rotor is constructed from zinc.  
     
     
       47. The apparatus of claim 46 wherein the rotor is constructed from die cast zinc.  
     
     
       48. The apparatus of claim 9 wherein the rotor is die cast.  
     
     
       49. The apparatus of claim 10 wherein the rotor is constructed from zinc.  
     
     
       50. The apparatus of claim 49 wherein the rotor is constructed from die cast zinc.  
     
     
       51. The apparatus of claim 10 wherein the rotor is die cast.  
     
     
       52. The apparatus of claim 11 wherein the rotor is constructed from zinc.  
     
     
       53. The apparatus of claim 52 wherein the rotor is constructed from die cast zinc.  
     
     
       54. The apparatus of claim 11 wherein the rotor is die cast.  
     
     
       55. The apparatus of claim 12 wherein the rotor is constructed from zinc.  
     
     
       56. The apparatus of claim 55 wherein the rotor is constructed from die cast zinc.  
     
     
       57. The apparatus of claim 12 wherein the rotor is die cast.  
     
     
       58. The apparatus of claim 13 wherein the rotor is constructed from zinc.  
     
     
       59. The apparatus of claim 58 wherein the rotor is constructed from die cast zinc.  
     
     
       60. The apparatus of claim 13 wherein the rotor is die cast.  
     
     
       61. The apparatus of claim 14 wherein the rotor is constructed from zinc.  
     
     
       62. The apparatus of claim 61 wherein the rotor is constructed from die cast zinc.  
     
     
       63. The apparatus of claim 14 wherein the rotor is die cast.  
     
     
       64. The apparatus of claim 15 wherein the rotor is constructed from zinc.  
     
     
       65. The apparatus of claim 64 wherein the rotor is constructed from die cast zinc.  
     
     
       66. The apparatus of claim 15 wherein the rotor is die cast.  
     
     
       67. The apparatus of claim 16 wherein the rotor is constructed from zinc.  
     
     
       68. The apparatus of claim 67 wherein the rotor is constructed from die cast zinc.  
     
     
       69. The apparatus of claim 16 wherein the rotor is die cast.  
     
     
       70. The apparatus of claim 17 wherein the rotor is constructed from zinc.  
     
     
       71. The apparatus of claim 70 wherein the rotor is constructed from die cast zinc.  
     
     
       72. The apparatus of claim 17 wherein the rotor is die cast.  
     
     
       73. The apparatus of claim 18 wherein the rotor is constructed from zinc.  
     
     
       74. The apparatus of claim 73 wherein the rotor is constructed from die cast zinc.  
     
     
       75. The apparatus of claim 18 wherein the rotor is die cast.  
     
     
       76. The apparatus of claim 19 wherein the rotor is constructed from zinc.  
     
     
       77. The apparatus of claim 76 wherein the rotor is constructed from die cast zinc.  
     
     
       78. The apparatus of claim 19 wherein the rotor is die cast.  
     
     
       79. The apparatus of claim 20 wherein the rotor is constructed from zinc.  
     
     
       80. The apparatus of claim 79 wherein the rotor is constructed from die cast zinc.  
     
     
       81. The apparatus of claim 20 wherein the rotor is die cast.  
     
     
       82. The apparatus of claim 21 wherein the rotor is constructed from zinc.  
     
     
       83. The apparatus of claim 82 wherein the rotor is constructed from die cast zinc.  
     
     
       84. The apparatus of claim 21 wherein the rotor is die cast.  
     
     
       85. A method of making an attenuator comprising providing a housing defining an interior, mounting a rotor for rotation within the housing about an axis of the rotor, providing first electrical contacts on the housing, providing second electrical contacts on the rotor, and providing multiple printed conductor (PC) boards for engaging respective second electrical contacts, mounting the rotor for rotation within the housing including mounting a die cast rotor for rotation within the housing, the providing of the multiple PC boards includes providing on each PC board an electrically relatively non-conductive substrate, providing on a first side of each PC board electrically relatively conductive areas and electrically relatively non-conductive areas, and coupling electrically attenuating elements together in attenuating networks with the electrically relatively conductive areas to provide selected levels of attenuation.  
     
     
       86. The method of claim 85 wherein the providing of the housing defining the interior comprises providing a housing defining a generally right circular cylindrical interior.  
     
     
       87. The method of claim 85 further including providing an index for indicating the position of the rotor within the housing.  
     
     
       88. The method of claim 85 further including providing a shaft, and mounting the rotor for rotation within the housing about an axis of the rotor includes providing a passageway through the rotor for receiving the shaft and providing on the shaft and passageway complementary features which mate when the shaft is received in the passageway.  
     
     
       89. The method of claim 85 wherein the providing of the housing defining the interior includes providing a front closure and a rear closure, and removably attaching at least one of the front closure and rear closure to the housing.  
     
     
       90. The method of claim 85 wherein the mounting of the rotor for rotation within the housing about the axis of the rotor includes providing on the rotor axially oppositely facing surfaces constructed from electrically relatively non-conductive materials, and providing second electrical contacts on the rotor includes providing the second electrical contacts on the axially oppositely facing surfaces.  
     
     
       91. The method of claim 90 wherein the providing on the rotor of axially oppositely facing surfaces constructed from electrically relatively non-conductive materials includes providing on the rotor axially oppositely facing resin surfaces.  
     
     
       92. The method of claim 85 further including providing a detent for promoting orientation of the rotor with selected ones of the second electrical contacts in electrical contact with respective ones of the first electrical contacts.  
     
     
       93. The method of claim 85 further including providing at least one groove in one of the outer perimeter of the rotor and the interior of the housing, and at least one resilient, electrically relatively conductive contact strip oriented in the groove.  
     
     
       94. The method of claim 85 wherein the providing of the multiple PC boards includes providing multiple PC boards, each of which includes a second side which is electrically relatively conductive, and coupling one of the electrically relatively conductive areas on the first side of each PC board to the second side of that respective PC board.  
     
     
       95. The method of claim 85 wherein the coupling of the electrically attenuating elements together in attenuating networks with the electrically relatively conductive areas to provide selected levels of attenuation includes coupling surface mount resistors together in attenuating networks with the electrically relatively conductive areas to provide selected levels of attenuation.  
     
     
       96. The method of claim 85 wherein the coupling of the electrically attenuating elements together in attenuating networks with the electrically relatively conductive areas to provide selected levels of attenuation includes coupling the electrically attenuating elements of the attenuator between respective conductive areas.  
     
     
       97. The method of claim 96 wherein the coupling of the electrically attenuating elements together in attenuating networks with the electrically relatively conductive areas to provide selected levels of attenuation includes coupling surface mount resistors together in attenuating networks with the electrically relatively conductive areas to provide selected levels of attenuation.  
     
     
       98. The method of claim 85 wherein the mounting of the rotor for rotation within the housing includes providing on an outer surface of the rotor slots which extend generally radially and axially of the outer surface, each slot being wide enough in a circumferential direction around the outer surface of the rotor to receive edgewise a respective one of the PC boards.  
     
     
       99. The method of claim 85 wherein the providing of multiple PC boards for engaging respective second electrical contacts includes providing on each PC board an electrically relatively conductive side and providing multiple strips of resilient electrically conductive material, capturing with each strip the radially inner edge of a respective PC board and making electrical contact with the electrically relatively conductive side of each PC board, with one of the conductive areas of each PC board, and with the rotor.  
     
     
       100. The method of claim 85 wherein the providing on each PC board of the electrically relatively non-conductive substrate includes providing on each PC board a resin substrate.  
     
     
       101. The method of claim 100 wherein the providing on each PC board of the resin substrate includes providing on each PC board a fiber reinforced resin substrate.  
     
     
       102. The method of claim 85 wherein the providing on each PC board of the electrically relatively non-conductive substrate includes providing on each PC board a fiber reinforced resin substrate.  
     
     
       103. The method of claim 102 wherein the providing on each PC board of the fiber reinforced resin substrate includes providing on each PC board a fiberglass substrate.  
     
     
       104. The method of claim 85 wherein the providing of the housing defining an interior includes providing a housing constructed from extruded aluminum.  
     
     
       105. The method of claim 85 wherein the providing of the housing defining the interior includes providing a housing constructed from aluminum tubing.  
     
     
       106. The method of claim 85 wherein the mounting of the die cast rotor for rotation within the housing about the axis of the rotor includes mounting a die cast zinc-containing rotor for rotation within the housing about an axis of the rotor.  
     
     
       107. The method of claim 86 wherein the mounting of the die cast rotor for rotation within the housing about the axis of the rotor includes mounting a die cast zinc-containing rotor for rotation within the housing about an axis of the rotor.  
     
     
       108. The method of claim 87 wherein the mounting of the die cast rotor for rotation within the housing about the axis of the rotor includes mounting a die cast zinc-containing rotor for rotation within the housing about an axis of the rotor.  
     
     
       109. The method of claim 88 wherein the mounting of the die cast rotor for rotation within the housing about the axis of the rotor includes mounting a die cast zinc-containing rotor for rotation within the housing about an axis of the rotor.  
     
     
       110. The method of claim 89 wherein the mounting of the die cast rotor for rotation within the housing about the axis of the rotor includes mounting a die cast zinc-containing rotor for rotation within the housing about an axis of the rotor.  
     
     
       111. The method of claim 90 wherein the mounting of the die cast rotor for rotation within the housing about the axis of the rotor includes mounting a die cast zinc-containing rotor for rotation within the housing about an axis of the rotor.  
     
     
       112. The method of claim 91 wherein the mounting of the die cast rotor for rotation within the housing about the axis of the rotor includes mounting a die cast zinc-containing rotor for rotation within the housing about an axis of the rotor.  
     
     
       113. The method of claim 92 wherein the mounting of the die cast rotor for rotation within the housing about the axis of the rotor includes mounting a die cast zinc-containing rotor for rotation within the housing about an axis of the rotor.  
     
     
       114. The method of claim 93 wherein the mounting of the die cast rotor for rotation within the housing about the axis of the rotor includes mounting a die cast zinc-containing rotor for rotation within the housing about an axis of the rotor.  
     
     
       115. The method of claim 94 wherein the mounting of the die cast rotor for rotation within the housing about the axis of the rotor includes mounting a die cast zinc-containing rotor for rotation within the housing about an axis of the rotor.  
     
     
       116. The method of claim 95 wherein the mounting of the die cast rotor for rotation within the housing about the axis of the rotor includes mounting a die cast zinc-containing rotor for rotation within the housing about an axis of the rotor.  
     
     
       117. The method of claim 96 wherein the mounting of the die cast rotor for rotation within the housing about the axis of the rotor includes mounting a die cast zinc-containing rotor for rotation within the housing about an axis of the rotor.  
     
     
       118. The method of claim 97 wherein the mounting of the die cast rotor for rotation within the housing about the axis of the rotor includes mounting a die cast zinc-containing rotor for rotation within the housing about an axis of the rotor.  
     
     
       119. The method of claim 98 wherein the mounting of the die cast rotor for rotation within the housing about the axis of the rotor includes mounting a die cast zinc-containing rotor for rotation within the housing about an axis of the rotor.  
     
     
       120. The method of claim 99 wherein the mounting of the die cast rotor for rotation within the housing about the axis of the rotor includes mounting a die cast zinc-containing rotor for rotation within the housing about an axis of the rotor.  
     
     
       121. The method of claim 100 wherein the mounting of the die cast rotor for rotation within the housing about the axis of the rotor includes mounting a die cast zinc-containing rotor for rotation within the housing about an axis of the rotor.  
     
     
       122. The method of claim 101 wherein the mounting of the die cast rotor for rotation within the housing about the axis of the rotor includes mounting a die cast zinc-containing rotor for rotation within the housing about an axis of the rotor.  
     
     
       123. The method of claim 102 wherein the mounting of the die cast rotor for rotation within the housing about the axis of the rotor includes mounting a die cast zinc-containing rotor for rotation within the housing about an axis of the rotor.  
     
     
       124. The method of claim 103 wherein the mounting of the die cast rotor for rotation within the housing about the axis of the rotor includes mounting a die cast zinc-containing rotor for rotation within the housing about an axis of the rotor.  
     
     
       125. The method of claim 104 wherein the mounting of the die cast rotor for rotation within the housing about the axis of the rotor includes mounting a die cast zinc-containing rotor for rotation within the housing about an axis of the rotor.  
     
     
       126. The method of claim 105 wherein the mounting of the die cast rotor for rotation within the housing about the axis of the rotor includes mounting a die cast zinc rotor for rotation within the housing about an axis of the rotor.