# US 10,371,010 B2 · Tie rod for a mid-turbine frame

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 10,371,010 B2
- Document ID: US10371010B2
- Status: Granted
- Kind: B2
- Application number: 14/598,574
- Filed: 2015-01-16
- Published: 2016-07-21
- Granted: 2019-08-06
- Earliest claimed: 2015-01-16
- Assignees: United Technologies Corporation
- Applicants: United Technologies Corporation
- Inventors: Jorge I. Farah; Steven D. Porter; Paul K. Sanchez; Joseph J. Sedor
- Web page: https://patentgrep.com/patent/US10371010B2

## CPC

- F01D 25/28: Supporting or mounting arrangements, e.g. for turbine casing
- F01D 9/065: {Fluid supply or removal conduits traversing the working fluid flow, e.g. for lubrication-, cooling-, or sealing fluids (see also F01D25/16, F01D25/24 and F01D25/26)}
- F01D 25/162: {Bearing supports}
- F02C 7/20: Mounting or supporting of plant; Accommodating heat expansion or creep
- F05D 2220/32: in gas turbines
- F05D 2230/60: Assembly methods
- F05D 2260/31: Retaining bolts or nuts
- F01D: NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES (machines or engines for liquids F03; non-positive displacement pumps F04D)
- F02C: GAS-TURBINE PLANTS; AIR INTAKES FOR JET-PROPULSION PLANTS; CONTROLLING FUEL SUPPLY IN AIR-BREATHING JET-PROPULSION PLANTS (construction of turbines F01D; jet-propulsion plants F02K; construction of compressors or fans F04; generating combustion products of high pressure or high velocity F23R; using gas turbines in compression refrigeration plants F25B11/00)
- F05D: INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS

## Abstract

A mid-turbine frame for a gas turbine engine includes an inner frame case that includes a bolt opening and at least one spoke for connecting an outer frame case to the inner frame case that includes an inlet passage that extends in a radial direction. A central bolt extends through the bolt opening for securing at least one spoke to the inner frame case.

## Claims

### Claim 1

A mid-turbine frame for a gas turbine engine comprising:
an inner frame case including a bolt opening;
at least one spoke for connecting an outer frame case to the inner frame case including an inlet passage extending in a radial direction, wherein a radially inner end of the at least one spoke includes at least two tabs; and
a central bolt extending through the bolt opening for securing the at least one spoke to the inner frame case, wherein the central bolt includes an airflow passage extending radially through the central bolt aligned with the inlet passage.

### Claim 2 (depends on 1)

The mid-turbine frame of claim 1, wherein the central bolt includes external threads that engage internal threads on the at least one spoke.

### Claim 3 (depends on 2)

The mid-turbine frame of claim 2, wherein the internal threads on the at least one spoke are located radially outward from the inner frame case.

### Claim 4 (depends on 2)

The mid-turbine frame of claim 2, wherein a head of the central bolt engages a radially inner surface of the inner frame case.

### Claim 5 (depends on 1)

The mid-turbine frame of claim 1, wherein the inner frame case includes at least two protrusions that form a groove for accepting the at least two tabs.

### Claim 6 (depends on 5)

The mid-turbine frame of claim 5, wherein the at least two protrusions are located on opposite sides of the bolt opening.

### Claim 7 (depends on 5)

The mid-turbine frame of claim 5, wherein the at least two protrusions include a first protrusion and a second protrusion axially aligned with the bolt opening.

### Claim 8 (depends on 7)

The mid-turbine frame of claim 7, wherein the first protrusion and the second protrusion extend from an upstream side of the bolt opening to a downstream side of the bolt opening.

### Claim 9 (depends on 8)

The mid-turbine frame of claim 8, wherein the first protrusion and the second protrusion at least partially define the bolt opening.

### Claim 10 (depends on 9)

The mid-turbine frame of claim 9, wherein the bolt opening defines a first curved recess in the first protrusion and a second curved recess in the second protrusion.

### Claim 11 (depends on 1)

The mid-turbine frame of claim 1, wherein the central bolt is located adjacent a surface of the inner frame case defining the bolt opening.

### Claim 12

A gas turbine engine comprising:
a mid-turbine frame located axially between a first turbine and a second turbine, the mid-turbine frame comprising:
an inner frame case including a bolt opening;
at least one spoke for connecting an outer frame case to the inner frame case including an inlet passage extending in a radial direction, wherein a radially inner end of the at least one spoke includes at least two tabs; and
a central bolt extending through the bolt opening for securing the at least one spoke to the inner frame case, wherein the central bolt includes an airflow passage extending radially through the central bolt aligned with the inlet passage.

### Claim 13 (depends on 12)

The gas turbine engine of claim 12, wherein the central bolt includes external threads that engage internal threads on the at least one spoke and the internal threads on the at least one spoke are located radially outward from the inner frame case.

### Claim 14 (depends on 12)

The gas turbine engine of claim 12, wherein the inner frame case includes at least two protrusions that form a groove for accepting the at least two tabs.

### Claim 15 (depends on 14)

The gas turbine engine of claim 14, wherein the at least two protrusions are located on opposite sides of the bolt opening.

### Claim 16 (depends on 14)

The gas turbine engine of claim 14, wherein the at least two protrusions include a first protrusion and a second protrusion axially aligned with the bolt opening.

### Claim 17 (depends on 16)

The gas turbine engine of claim 16, wherein the first protrusion and the second protrusion extend from an upstream side of the bolt opening to a downstream side of the bolt opening.

### Claim 18 (depends on 16)

The gas turbine engine of claim 16, wherein the first protrusion and the second protrusion at least partially define the bolt opening.

### Claim 19 (depends on 18)

The gas turbine engine of claim 18, wherein the bolt opening defines a first curved recess in the first protrusion and a second curved recess in the second protrusion.