SPRING-BODIED DEVICE FOR IN-SITU OVERHEAT ALERT FOR EQUIPMENT
First Claim
1. A reusable device for placement in thermal communication with a machine, the device serving to detect and give notice of an overheating condition in the machine when the machine is operating or has been operating;
- the device comprising;
a unitary sheet metal body formed of a metal sheet having a spring temper and bent at multiple locations to create a shaped multi-segment body, the body comprising a base segment, the base segment being adapted for surface to surface contact with the machine;
a shape memory alloy (SMA) wire which undergoes a transformation from martensite to austenite and a shape change when it is heated to a predetermined temperature, indicative of an overheating condition in a machine, the SMA wire having first and second ends and being suitably secured at its ends to the shaped sheet metal body so as to position the SMA wire in thermal communication with the machine; and
the sheet metal body further comprisinga flexible arcuate segment with a flag-member, the flexible arcuate segment being connected to the base segment by a torsionable hinge portion, the flag-member having a surface area for displaying a visible indication of overheating in the machine, the arcuate segment being maintained in a stored position in the device when the machine has not experienced an overheating condition, the flag-member being hidden from view when the arcuate segment is in its stored position, the arcuate segment being releaseable from its stored position by activation of the SMA wire when the SMA wire is heated to its predetermined temperature by thermal communication with the machine and experiences its shape change so that the arcuate segment, once released from its stored position pivots about the torsionable hinge portion to bring the flag-member into a viewable position;
the device being resettable, so that the released arcuate segment may be repositioned into its stored position enabling the device to again detect and give notice of an overheating condition in the machine.
3 Assignments
0 Petitions
Accused Products
Abstract
Malfunction or failure of mechanical, electrical and electro-mechanical equipment, for example equipment used in manufacturing operations, is often preceded by an increase in the operating temperature of at least some portion of the equipment. Some pre-determined temperature, greater than the highest normal operating temperature of the equipment, is presumed or known to be indicative of impending equipment failure if no remedial action is taken. A resettable, temperature-sensitive device, containing a shape memory alloy actuator, pre-selected to operate at the pre-determined temperature, is disclosed. The device is placed in thermal contact with the equipment. If the equipment achieves the pre-determined temperature, the shape memory alloy actuator causes the device to display a flag or provide some other passive visual indication. Alternatively, or additionally, the actuator may trigger an electrically-powered alert including visual or audible alerts or a wireless communication.
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Citations
26 Claims
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1. A reusable device for placement in thermal communication with a machine, the device serving to detect and give notice of an overheating condition in the machine when the machine is operating or has been operating;
- the device comprising;
a unitary sheet metal body formed of a metal sheet having a spring temper and bent at multiple locations to create a shaped multi-segment body, the body comprising a base segment, the base segment being adapted for surface to surface contact with the machine; a shape memory alloy (SMA) wire which undergoes a transformation from martensite to austenite and a shape change when it is heated to a predetermined temperature, indicative of an overheating condition in a machine, the SMA wire having first and second ends and being suitably secured at its ends to the shaped sheet metal body so as to position the SMA wire in thermal communication with the machine; and
the sheet metal body further comprisinga flexible arcuate segment with a flag-member, the flexible arcuate segment being connected to the base segment by a torsionable hinge portion, the flag-member having a surface area for displaying a visible indication of overheating in the machine, the arcuate segment being maintained in a stored position in the device when the machine has not experienced an overheating condition, the flag-member being hidden from view when the arcuate segment is in its stored position, the arcuate segment being releaseable from its stored position by activation of the SMA wire when the SMA wire is heated to its predetermined temperature by thermal communication with the machine and experiences its shape change so that the arcuate segment, once released from its stored position pivots about the torsionable hinge portion to bring the flag-member into a viewable position; the device being resettable, so that the released arcuate segment may be repositioned into its stored position enabling the device to again detect and give notice of an overheating condition in the machine. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14)
- the device comprising;
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15. A device for placement on a machine for the purpose of detecting an overheating condition during operation of the machine, the device being in a closed position during normal machine operation and movable to an open position for indication of the overheating condition, the device comprising:
a multi-segment, flexible, bent-shaped, sheet metal member and a shape memory alloy wire attached to a segment of the bent-shaped sheet metal member, the shape memory alloy wire experiencing a metallurgical phase change, when heated to a temperature indicative of the overheating condition, to shorten its length and to thereby release the flexible, bent-shaped, sheet metal member from a closed position such it self-flexes to an open position in which the sheet member then indicates an overheating condition of the machine. - View Dependent Claims (16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26)
Specification