Fixtureless environmental stress screening apparatus
First Claim
1. An apparatus for thermally and vibrationally testing a device comprising:
- a vessel in which said device is placed;
means for selectively dispensing a cold liquid into said vessel to thermally test said device;
means for selectively dispensing a hot liquid into said vessel to thermally test said device;
means for transmitting vibratory motion directly to said device through any liquid placed within said vessel to vibrationally test said device; and
means for selectively draining said any liquid from said vessel.
1 Assignment
0 Petitions
Accused Products
Abstract
A fixtureless environmental screening device is provided for the testing of mechanical, electromechanical and electrical devices. The apparatus uses a relatively incompressible fluid having a high heat capacity and a high heat of vaporization to transfer heat and vibration to a device to be tested. The heat transfer characteristics of the fluid permits a device tested to undergo rapid temperature change while being simultaneously subjected to vibrational cycling. By utilizing a fluid as a vibration transmission medium expensive fixtures are avoided so that devices of a wide variety of shapes and sizes may be readily tested. The dielectric properties of the working fluid permits energization of electrical devices during the course of vibration and temperature cycling.
57 Citations
39 Claims
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1. An apparatus for thermally and vibrationally testing a device comprising:
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a vessel in which said device is placed; means for selectively dispensing a cold liquid into said vessel to thermally test said device; means for selectively dispensing a hot liquid into said vessel to thermally test said device; means for transmitting vibratory motion directly to said device through any liquid placed within said vessel to vibrationally test said device; and means for selectively draining said any liquid from said vessel. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
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11. An apparatus for testing electrical, electromechanical and mechanical devices comprising:
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a vessel in which a device to be tested is placed; a reservoir of below-zero degree Celsius liquid; a reservoir of above-zero degree Celsius liquid, said below-zero degree Celsius liquid and said above-zero degree Celsius liquid differing in temperature by at least 40 degrees Celsius, means disposed between said vessel and each of said reservoirs for piping said below-zero degree Celsius liquid and said above-zero degree Celsius liquid between said reservoirs and said vessel; means for controlling the flow of said below-zero degree Celsius liquid and said above-zero degree Celsius liquid between said reservoirs and said vessel; means for transmitting vibratory motion to said device directly through any liquid piped into said vessel; and
means for selectively draining said any liquid within said vessel from said vessel. - View Dependent Claims (12, 13, 14, 15, 16)
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17. An apparatus for testing a device comprising:
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a vessel in which said device is placed; a reservoir of cold fluid coupled to said vessel so that said cold fluid may be selectively dispensed into said vessel; a reservoir of hot fluid coupled to said vessel so that said hot fluid may be selectively dispensed into said vessel; a flexible diaphragm that covers an opening defined in a surface of said vessel; an electromechanical transducer coupled to said flexible diaphragm so that vibratory motion of said electromechanical transducer is coupled to any fluid within said vessel; and a valve coupled to said vessel for selectively draining at least a portion of said any fluid within said vessel from said vessel. - View Dependent Claims (18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28)
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29. An apparatus for testing electrical, electromechanical and mechanical devices comprising:
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a vessel in which a device to be tested is placed; a reservoir of below-zero degree Celsius fluid; a reservoir of above-zero degree Celsius fluid, said below-zero degree Celsius fluid and said above-zero degree Celsius fluid differing in temperature by at least 40 degrees Celsius, means disposed between said vessel and each of said reservoirs for piping said below-zero degree Celsius fluid and said above-zero degree Celsius fluid between said reservoirs and said vessel; means for controlling the flow of said below-zero degree Celsius fluid and said above-zero degree Celsius fluid between said reservoir and said vessel; a temperature sensor disposed within said vessel for sensing the temperature of any fluid within said vessel; means for transmitting vibratory motion directly to said any fluid piped into said vessel, wherein said vibratory motion is transmitted through said any fluid to said device; a motion detector operably coupled to any device to be tested to detect vibrational movement of said device; means for selectively energizing an electrical device to be tested and an electromechanical device to be tested; and means for selectively draining said any fluid within said vessel from said vessel. - View Dependent Claims (30, 31, 32)
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33. An apparatus for thermally and vibrationally testing a device comprising:
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a vessel in which said device is placed; means for selectively dispensing cold FLUORINERT liquid into said vessel to thermally test said device, said cold FLUORINERT liquid being at a temperature that is below the freezing point of water; means for selectively dispensing hot FLUORINERT liquid into said vessel to thermally test said device, in which said cold FLUORINERT liquid and said hot FLUORINERT liquid differ by a temperature of at least 40 degrees Celsius; means for transmitting vibratory motion directly to any FLOURINERT liquid placed within said vessel to vibrationally test said device, wherein said vibratory motion is transmitted through said any FLOURINERT liquid to said device; and means for selectively draining said any FLOURINERT liquid from said vessel.
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34. An apparatus for thermally and vibrationally testing a device comprising:
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a vessel in which said device is placed; means for selectively dispensing a cold fluid into said vessel to thermally test said device, said cold fluid being at a temperature that is below the freezing point of water; means for selectively dispensing a hot fluid into said vessel to thermally test said device; means for transmitting vibratory motion directly to any fluid placed within said vessel to vibrationally test said device, wherein said vibratory motion is transmitted through said any fluid to said device, said means including a piezoelectric element transducer attached to said vessel for converting electrical power into mechanical motion; and means for selectively draining said any fluid from said vessel.
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35. An apparatus for thermally and vibrationally testing a device comprising;
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a vessel in which said device is placed; means for selectively dispensing a cold fluid into said vessel to thermally test said device, said cold fluid being at a temperature that is below the freezing point of water; means for selectively dispensing a hot fluid into said vessel to thermally test said device; means for transmitting vibratory motion directly to any fluid placed within said vessel to vibrationally test said device, wherein said vibratory motion is transmitted through said any fluid to said device, said means including a transducer that converts electrical power into mechanical motion and that is suspended within said vessel so that any fluid placed within said vessel makes fluid contact with said transducer; and means for selectively draining said any fluid from said vessel.
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36. An apparatus for thermally and vibrationally testing a device comprising:
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a vessel in which said device is placed; means for selectively dispensing a cold fluid into said vessel to thermally test said device, said cold fluid being at a temperature that is below the freezing point of water; means for selectively dispensing a hot fluid into said vessel to thermally test said device; means for transmitting vibratory motion directly to any fluid placed within said vessel to vibrationally test said device, wherein said vibratory motion is transmitted through said any fluid to said device, said means including an electrically driven shaker having an oscillating member coupled to a flexible bladder that covers an opening defined in said vessel; and means for selectively draining said any fluid from said vessel.
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37. An apparatus for testing electrical, electromechanical and mechanical devices comprising:
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a vessel in which a device to be tested is placed; a reservoir of below-zero degree Celsius fluid; a reservoir of above-zero degree Celsius fluid, said below-zero degree Celsius fluid and said above-zero degree Celsius fluid differing in temperature by at least 40 degrees Celsius, means disposed between said vessel and each of said reservoirs for piping said below-zero degree Celsius fluid and said above-zero degree Celsius fluid between said reservoirs and said vessel; means for controlling the flow of said below-zero degree Celsius fluid and said above-zero degree Celsius fluid between said reservoirs and said vessel; means for transmitting vibratory motion directly to any fluid piped into said vessel including an electromechanical transducer coupled to a flexible diaphragm that covers an opening defined in a wall of said vessel so that vibratory motion of said electromechanical transducer is coupled to said any fluid within said vessel by said flexible diaphragm responding to motion imparted to it by said electromechanical transducer, wherein said vibratory motion is transmitted through said any fluid to said device; means for selectively energizing an electrical device to be tested and an electromechanical device to be tested; and means for selectively draining said any fluid within said vessel from said vessel.
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38. An apparatus for testing electrical, electromechanical and mechanical devices comprising:
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a vessel in which a device to be tested is placed; a reservoir of below-zero degree Celsius fluid; a reservoir of above-zero degree Celsius fluid, said below-zero degree Celsius fluid and said above-zero degree Celsius fluid differing in temperature by at least 40 degrees Celsius, means disposed between said vessel and each of said reservoirs for piping said below-zero degree Celsius fluid and said above-zero degree Celsius fluid between said reservoirs and said vessel; means for controlling the flow of said below-zero degree Celsius fluid and said above-zero degree Celsius fluid between said reservoirs and said vessel; means for transmitting vibratory motion directly to any fluid piped into said vessel including a piezoelectric element attached to said vessel, wherein said vibratory motion is transmitted through said any fluid to said device; means for selectively energizing an electrical device to be tested and an electromechanical device to be tested; and means for selectively draining said nay fluid within said vessel from said vessel.
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39. An apparatus for testing electrical, electromechanical and mechanical devices comprising:
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a vessel in which a device to be tested is placed; a reservoir of below-zero degree Celsius fluid; a reservoir of above-zero degree Celsius fluid said below-zero degree Celsius fluid and said above-zero degree Celsius fluid differing in temperature by at least 40 degrees Celsius, means disposed between said vessel and each of said reservoirs for piping said below-zero degree Celsius fluid and said above-zero degree Celsius fluid between said reservoirs and said vessel; means for controlling the flow of said below-zero degree Celsius fluid and said above-zero degree Celsius fluid between said reservoirs and said vessel; means for transmitting vibratory motion directly to any fluid piped into said vessel including a transducer that is suspended within said vessel so that said any fluid placed within said vessel makes fluid contact with said transducer, wherein said vibratory motion is transmitted through said any fluid to said device; means for selectively energizing an electrical device to be tested and an electromechanical device to be tested; and means for selectively draining said any fluid within said vessel from said vessel.
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Specification