Heat dispersion, heat dissipation and thermal indication for wheel set assembly

• US 20030006655A1
• Filed: 05/08/2002
• Published: 01/09/2003
• Est. Priority Date: 05/10/2001
• Status: Abandoned Application

• Current Assignee: Ming Zhang
• Original Assignee: Ming Zhang
• Inventors: Zhang, Ming (Jason)
• Application Number:
  US10/141,381
• Publication Number:
  US 20030006655A1
• Time in Patent Office: Days
• US Class Current: 310/52
• CPC Class Codes: B61K 9/04 Detectors for indicating the overheating of axle bearings and the like, e.g. associated with the brake system for applying the brakes in case of a fault
• CPC Class Codes: F16C 19/525 related to temperature and heat, e.g. insulation
• CPC Class Codes: F16C 37/007 of rolling bearings

Abstract

The present invention provides methods for

(1) first of all, rapid heat dispersion and precise thermal indication of shaft/shaft bearing assembly used in railway wheel set assemblies when bearing temperature is below a critical value;

(2) then self-initiated intensive heat dissipation once the bearing temperature is over the critical value.

The methods comprise:

(1) assembling a vehicle wheel set by mounting bearings and wheels on a railway shaft or axle with interference fit and mounting bearing adapter onto bearings;

(2) embedding heat pipe or other highly thermal conductive elements within the said vehicle wheel set;

(3) having the heat pipe only in thermal engagement within the confine of bearing, section of the axle or bearing adapter adjacent to the bearing when bearing temperature is below a critical value;

(4) having, beyond the aforesaid thermally engaged surface area, another substantially large surface area of the heat pipe that is in poor if not non thermal engagement with the shaft/shaft bearing assembly when bearing temperature is below certain critical value, and embedding, within the railway vehicles, at least one reservoir of low-melting-temperature fusible metal that transforms from solid to liquid phase and flows into the originally poorly engaged interfaces by capillary force once the bearing temperature is over the critical value;

(5) effecting rapid heat dispersion and prompt thermal indication at relatively low temperature therefore improving operational safety and visibility toward the available bearing failure detection means, and self-initiating additional intensive heat dissipation for retarding the progress of heat related bearing failure process once the temperature reaches to a critical value at which the lubricant or grease within the bearing starts to evaporate or ceases to be effective.

Claims

1. An apparatus for heat dispersion within a shaft/shaft bearing assembly in a rotating machinery or in a vehicle, the apparatus comprising at least:

(a) a shaft/shaft bearing assembly including at least one shaft, one shaft bearing mounted to the said shaft and one bearing adapter mounted on the said shaft bearing, both the shaft and the bearing adapter being at least partially in thermal engagement with the shaft;

(b) heat dissipation areas on the surfaces of the machinery or the vehicle adjacent to the shaft bearing such as the surfaces of the said shaft, shaft bearing, bearing adapter, and additional heat dissipation components mounted to the said rotating machinery or the said vehicle;

(c) highly thermal conductive element embedded in the said shaft/bearing assembly, the said highly thermal conductive element

(1) having at least one section in thermal engagement with the shaft/shaft bearing assembly, the thermally engaged section being substantially adjacent to potentially heat concentrated zones within the shaft bearing, the shaft and the bearing adapter;

(2) effecting rapid dispersion for heat concentrated in substantially small high-temperature zones in the said shaft/shaft bearing by transferring/redistributing the concentrated heat to the whole thermally engaged interfaces of the said highly thermal conductive element, resulting in flattened and slow temperature rises in the small high temperature zones and broadened and relatively accelerated temperature rises in the rest of the surrounding zones;

(3) enabling improvement in operational safety of the shaft/shaft bearing assembly and retarding progress of potential heat related failure of the shaft/shaft bearing assembly by aforesaid rapid heat dispersion.

2. The highly thermal conductive element, as recited in claim 1, is a heat pipe means

(a) having a thermal conductive exterior shell forming a gas-tight container in which it contains a small amount of vaporizable fluid;

(b) serving as a heat sink or heat spreader in which the fluid vaporizes in the section of the heat pipe adjacent to the high temperature zones and then the transformed vapor flows towards/condenses in the rest of the heat pipe where temperatures are lower, therefore transferring the heat rapidly from the high temperature zones to the rest of the cooler zones.

3. The apparatus for heat dispersion, as recited in claim 1, is further characterized by

(a) comprising thermal indication areas monitored by either detectors or sensors that are either contact or no contact type, the said thermal indication areas being substantially small parts of the said heat dissipation areas;

(b) enabling, with the help of embedded highly thermal conductive elements, prompt thermal indications of the said shaft/shaft bearing assembly by virtue of the said broadened and accelerated temperature rises in the zones surrounding the thermally engaged part of the highly thermal conductive elements that are adjacent to the said thermal indication areas and by virtue of no substantially accelerated heat loss from the large heat dissipation areas.

4. The apparatus for heat dispersion and thermal indication, as recited in claim 3, is further characterized by having a thermal indication area on surface of an additional thermal indication means, the said additional thermal indication means

(a) locating within the scan envelope or being in thermal contact with a heat detector or heat sensor and being substantially far from the shaft bearing;

(b) being in thermal engagement with highly thermal conductive element that serve as heat dispersion means for the shaft/shaft bearing assembly;

(c) receiving heat rapidly from the highly thermal conductive element and providing prompt temperature changes in the thermal indication area.

5. The additional thermal indication means, as recited in claim 4, is further characterized by

(a) being mounted to the rotating machinery or the vehicle where the shaft/shaft bearing assembly is included and is scanned by non contact heat detection means;

(b) having a core section made of highly thermal conductive material and an outer ring or a layer of coating in a material similar to the bearing or bearing housing with substantially identical heat adsorption and/or heat emission characteristics;

(c) being substantially thermal insulated from the rotating machinery or the vehicle or other surroundings except the areas scanned by the non contact heat detection means.

6. The apparatus for heat dispersion, as recited in claim 1, is further characterized in that

(a) the embedded highly thermal conductive element has, beyond the aforesaid thermally engaged surface area, another substantially large surface area that is in poor if not non thermal engagement with the shaft/shaft bearing assembly when the bearing temperature is below a critical value;

(b) a self-activated interface thermal resistance converter means is embedded within the shaft/shaft bearing assembly either in contact with or substantially adjacent to the highly thermal conductive element, and reduces substantially, once the bearing temperature reaches to the critical value, thermal resistance on the interfaces that originally, only poor if not non thermal engagement exist;

(c) a rapid internal heat dispersion is realized substantially adjacent to the heat concentrated zones within the shaft bearing, the shaft and the bearing adapter when the bearing temperature is below certain critical value, and a rapid heat dissipation is realized by virtue of rapid heat transfer across the whole length of the heat pipe and by virtue of substantial reduction of thermal contact resistance across the aforesaid interfaces once the bearing temperature reaches the said critical value.

7. The critical value of bearing temperature in claim 6 is the evaporation temperature for the bearing lubrication agent or grease contained within the shaft bearing, ranging from 150°

F. to 650°

F.

8. The self-activated interface thermal resistance converter, as recited in claim 6, is further characterized by

(a) comprising one or a plurality of reservoirs filled with low-melting-point fusible metal that transforms from solid phase to liquid phase above the said critical temperature;

(b) being embedded in the shaft/shaft bearing assembly and either in contact with or adjacent to the said surface area of the heat pipe means that is in poor if not non thermal engagement with the shaft/shaft bearing assembly when the bearing temperature is below the said critical temperature;

(c) releasing automatically above the critical bearing temperature the transformed liquid phase fusible metal to the interface of the section of the heat pipe in poor thermal contact with the shaft/shaft bearing assembly and reducing significantly thermal resistance on the said interface.

9. The apparatus in claim 1, wherein

(a) the bearing adapter is one of the following type:

bearing pillow block, combined bearing housing and bearing mounting/support base, vehicle bearing adapter etc.;

(b) the said highly thermal conductive element is embedded in one or a combination of following locations within the said shaft/shaft bearing assembly including;

aperture/bores created or existed along the shaft, enlarged cap screw holes at the end of the shaft, and aperture/bores created or existed in the bearing adapter;

(c) the additional heat dissipation components are cooling fins or ventilators built into or attached to the rotary components of the rotating machinery or the vehicle.

10. The apparatus in claim 1, wherein

(a) the shaft/shaft bearing assembly is part of a railway vehicle wheel set assembly including tapered roller bearings and wheels mounted on a railway axle with interference fits, bearing adapters mounted onto the said bearings;

(b) the said heat pipe means that is used as highly thermal conductive element, is embedded in one or a combination of following locations within the said railway vehicle wheel set assembly including;

center of the solid axle, inner bore of the hollow axle, enlarged cap screw holes at the end of the axle, additional holes at the end of the axle, and holes in the bearing adapter;

(c) the said additional heat dissipation components are cooling fins or ventilators mounted at the end of the axle, on the axle end caps, or cooling fins mounted on the sides of bearing adapters.

11. The said heat pipes means, as recited in claim 10, is further characterized by

(a) being embedded in an aperture axially extended within the axle;

(b) either having a length shorter than the axial length of the railway bearing and locating under the bearing, or having an overall length substantially longer than the said railway bearing but only being thermally engaged with the section of the axle axially within the confine of the bearing.

12. The thermal indication areas, as recited in claim 3, are the scan envelopes in railway vehicle wheel set monitored by wayside hot box detectors.

14. The highly thermal conductive elements, as recited in claim 13, is a heat pipe means

(a) having a thermal conductive exterior shell forming a gas-tight container in which it contains a small amount of vaporizable fluid;

(b) serving as a heat sink in which the fluid vaporizes inside the high temperature section of the heat pipe and flows towards/condenses in the rest of the heat pipe where the temperatures are lower therefore transferring the heat rapidly to the rest of the cooler section of the heat pipe.

16. The highly thermal conductive element, as recited in claim 15, is a heat pipe means

(a) having a thermal conductive exterior shell forming a gas-tight container in which it contains a small amount of vaporizable fluid;

(b) serving as a heat sink in which the fluid vaporizes inside this high temperature section of the heat pipe and flows towards/condenses in the rest of the heat pipe where the temperatures are lower therefore transferring the heat rapidly to the rest of the cooler sections of the heat pipe.

17. The method for rapidly dispersing heat within a shaft/shaft bearing assembly, as recited in claim 15, is further characterized in that

(a) the embedded highly thermal conductive element has, beyond the aforesaid thermally engaged surface area, another substantially large surface area that is in poor if not non thermal engagement with the shaft/shaft bearing assembly when the bearing temperature is below a critical value;

(b) a self-activated interface thermal resistance converter means is embedded within the shaft/shaft bearing assembly either in contact with or substantially adjacent to the highly thermal conductive element, and reduces substantially, once the bearing temperature reaches to the critical value, thermal resistance on the interfaces that originally, only poor if not non thermal engagement exist;

(c) a rapid internal heat dispersion and a prompt thermal indication are realized substantially within the shaft bearing, the shaft and the bearing adapter when bearing temperature is below certain critical value, and additional rapid heat dissipation is further realized by virtue of rapid heat transfer across the whole length of the heat pipe and by virtue of substantial reduction of thermal contact resistance across the aforesaid interfaces once the bearing temperature reaches the said critical value.

19. The highly thermal conductive elements, as recited in claim 18, is a heat pipe means

(a) having a thermal conductive exterior shell forming a gas-tight container in which it contains a small amount of vaporizable fluid;

(b) serving as a heat sink in which the fluid vaporizes inside this high temperature section of the heat pipe and flows towards/condenses in the rest of the heat pipe where the temperatures are lower therefore transferring the heat rapidly to the rest of the cooler section of the heat pipe.

13. An apparatus for rapidly dissipating heat from shaft/shaft bearing assembly in a rotating machinery or a vehicle, the apparatus comprising:

(a) a shaft/shaft bearing assembly including at least one shaft, one shaft bearing mounted to the said shaft and one bearing adapter mounted on the said shaft bearing, both the shaft and bearing adapter being at least partially in thermal engagement with the shaft;

(b) heat dissipation areas on the surfaces of the machinery or the vehicle adjacent to the shaft bearing such as the surfaces of the said shaft, shaft bearing, bearing adapter, and additional heat dissipation components mounted to the said rotating machinery or the said vehicle;

(c) highly thermal conductive element embedded in the said shaft/shaft bearing assembly, the said highly thermal conductive element transferring heat concentrated in substantially small high-temperature zones to the rest of large low temperature zones and then dissipating the heat to atmosphere from substantially large heat dissipation area.

15. A method for rapidly dispersing heat from shaft/shaft bearing assemblies in a rotating machinery or a vehicle, the method comprising:

(a) assembling shaft/shaft bearing assembly by mounting shaft bearing on a shaft and then mounting bearing adapters onto the said bearings assemblies;

having both the shaft and the bearing adapter in at least partially thermal engagement with the said bearing;

(b) including within heat dissipation areas that are on the surfaces of the machinery or the vehicle, substantially small thermal indication areas that are monitored by heat detector or sensors of either contact or non contact type;

(c) embedding within the said shaft/shaft bearing assembly highly thermal conductive element that

(1) has at least one section in thermal engagement with the shaft/shaft bearing assembly, the thermally engaged section being substantially adjacent to potentially heat concentrated zones within the shaft bearing, the shaft and the bearing adapter;

(2) effects rapid dispersion for heat concentrated in substantially small high-temperature zones in the said shaft/shaft bearing by transferring/redistributing the concentrated heat to the whole thermally engaged interfaces of the said highly thermal conductive element, resulting in flattened and slow temperature rises in the small high temperature zones and broadened and relatively accelerated temperature rises in rest of the surrounding zones;

(3) enables improvement in operational safety of the shaft/shaft bearing assembly and retards progress of potentially heat related shaft/shaft bearing assembly failure process by aforesaid rapid heat dispersion of the concentrated heat;

(4) enables prompt thermal indications of the said shaft/shaft bearing assembly by virtue of aforesaid rapid dispersion of concentrated heat which accelerates temperature rises in the zones surrounding the thermally engaged part of the interfaces, thus accelerating also temperature rises in the said thermal indication areas, and by virtue of no substantially accelerated heat loss from the large heat dissipation areas.

18. A method for rapidly dissipating heat from shaft/shaft bearing assemblies in a rotating machinery or a vehicle, the method comprising:

(a) assembling shaft/shaft bearing assembly by mounting shaft bearing on a shaft and then mounting bearing adapters onto the said bearings assemblies;

having both the shaft and the bearing adapters in at least partially thermal engagement with the said bearing;

(b) providing heat dissipation areas on the surfaces of the machinery or the vehicle including the said shaft, shaft bearing, bearing adapter, and additional heat dissipation components mounted to the said rotating machinery or the said vehicle;

(c) embedding within the said shaft/shaft bearing assembly a highly thermal conductive element that transfers heat concentrated in substantially small high-temperature zones to the rest of large low temperature zones and then dissipates the heat to atmosphere from substantially large heat dissipation area.