Heat shield

Claim 2

In a turbo-compressor unit comprising a compressor impeller, a turbine blade wheel axially aligned with the compressor impeller and connected thereto to drive the same, and a stationary supporting structure located between the impeller and blade wheel; an annular heat shield structure located in a substantially radial plane between the impeller and blade wheel and secured to said supporting structure, one side of said shield structure being subjected to hot gases in the turbine blade wheel during operation of the unit, said shield structure comprising at least three segments, said segments being individually secured to said supporting structure and each of said segments being substantially smaller than the assembled at least three segments, said segments being interconnected to define a substantially gasimpervious annular shield by means of elastic and sealing connecting means allowing each segment to perform, substantially independently of the adjacent segments, the deformations due to the increase in temperature and the temperature gradients in the segments during operation of the unit.

Claim 3

The heat shield as claimed in claim 1, in which said elastic and sealing connecting means comprises a groove provided in each of the opposed edges of adjacent segments and a thin strip accommodated within the two grooves of each two opposed edges of adjacent segments, and each strip having a width equal to or less than twice the depth of each groove and greater than the depth of a groove plus the maximum distance between the opposed edges of adjacent segments when cold.

Claim 4

In a turbo-compressor unit comprising a compressor impeller, a turbine blade wheel axially aligned with the compressor impeller and connected thereto to drive same, and a stationary supporting structure located between the impeller and blade wheel, an annular heat shield structure, located in a substantially radial plane between the impeller and blade wheel and secured to said supporting structure, one side of such shield structure being subjected to hot gases in the turbine blade wheel during operation of the unit, said shield structure comprising segments, said segments being individually secured to said supporting structure and each of said segments being substantially smaller than the assembled segments, said segments being interconnected to define a substantially gas-impervious annular shield by means of elastic and sealing connecting means allow each segment to perform, substantially independently of the adjacent segments, the deformations due to the increase in temperature and the temperature gradients in the segments during operation of the unit, and each segment being fixedly secured at one point only and restrained from substantial movement in the axial direction of the turbo-compressor unit at two further points.

Claim 5

In a turbo-compressor unit comprising a compressor impeller, a turbine blade wheel axially aligned with the compressor impeller and connected thereto to drive same, and a stationary supporting structure located between the impeller and blade wheel, an annular heat shield structure, located in a substantially radial plane between the impeller and blade wheel and secured to said supporting structure, one side of such shield structure being subjected to hot gases in the turbine blade wheel during operation of the unit, said shield structure comprising segments, said segments being individually secured to said supporting structure and each of said segments being substantially smaller than the assembled segments, said segments being interconnected to define a substantially gas-impervious annular shield by means of elastic and sealing connecting means allow each segment to perform, substantially independently of the adjacent segments, the deformations due to the increase in temperature and the temperature gradients in the segments during operation of the unit, and each segment being fixedly secured at one point only and restrained from substantial movement in the axial direction of the turbo-compressor unit at two further points.

Claim 6

The heat shield as claimed in claim 3, in which the fixed securing point is located at the radially outer edge of the segment, while the two further restraining points are located at the radially inner edge.

Claim 7

The heat shield as claimed in claim 4, in which the restraining points at the radially inner edge of each segment are located at either end of the segment, and fastening means for fastening the segment at each of such restraining points being common to two adjacent segments.

Claim 8

The heat shield as claimed in claim 4, in which fastening means for fastening a segment at each of the restraining points at The radially inner edge comprises a headed bolt extending at right angles to the plane of the segment and spring biased in its axial direction, and the inner edge of the segment being provided with a recess for the bolt.

Claim 9

The heat shield as claimed in claim 4, in which each segment at its radially outer edge has an axially extending flange, fastening means for fastening the segment at at the fastening point located at the radially outer edge of the segment extending radially through said flange.