Hydraulic unit cylinder block for integrated drive generator

Patent metadata

Field	Value
Publication number	US-10539213-B2
Application number	US-201715723481-A
Country	US
Kind code	B2
Filing date	Oct 3, 2017
Priority date	Oct 3, 2017
Publication date	Jan 21, 2020
Grant date	Jan 21, 2020

Abstract

A cylinder block for use in an integrated drive generator has a shaft portion with a relatively small outer diameter and a cylindrical body portion having a larger outer diameter than the shaft portion, and said cylindrical body portion formed with a plurality of piston chambers, said cylindrical body portion extending from a first end to a second end, said second end being provided with cylindrical ports leading into said piston chambers and said cylindrical ports having a third end and a fourth end wherein a ratio of a first distance from said first end to said fourth end to a second distance from said first end to said second end being between 0.91 and 0.93. A generator and a method are also described.

First claim

The invention claimed is:

1. A cylinder block for use in an integrated drive generator comprising:
a shaft portion having a relatively small outer diameter;
a cylindrical body portion having a larger outer diameter than the shaft portion, and said cylindrical body portion formed with a plurality of piston chambers, said cylindrical body portion extending from a first end to a second end, said second end being provided with ports leading into said piston chambers and said ports having a third end and a fourth end wherein a ratio of a first distance from said first end to said fourth end to a second distance from said first end to said second end being between 0.91 and 0.93;
wherein said ports being kidney-shaped;
wherein said kidney-shaped ports having a width and a ratio of a depth of said kidney-shaped port, to said width is between 0.48 and 0.62;
wherein a wear plate is affixed to said second end of said cylindrical body portion; and
wherein said wear plate having ports aligned with said ports in said cylindrical body.

2. The cylinder block as set forth in claim 1 , wherein said wear plate is formed of a lead-free bronze.

3. The cylinder block as set forth in claim 2 , wherein said lead-free bronze is ASTM B505, alloy C90700.

4. An integrated drive generator comprising:
an input shaft for driving a differential;
said differential for providing an input drive to a generator for generating electricity, and said differential also being connected with a hydraulic unit, said hydraulic unit including a variable swash plate and a fixed swash plate, and each of said swash plates being associated with a set of pistons, a pair of cylinder blocks with one of said cylinder blocks being associated with each of said sets of pistons;
said cylinder blocks having a shaft portion with a relatively small outer diameter and a cylindrical body portion having a larger outer diameter than the shaft portion, and said cylindrical body portion formed with a plurality of piston chambers, said cylindrical body portion extending from a first end to a second end, said second end being provided ports leading into said piston chambers and said ports having a third end and a fourth end wherein a ratio of a first distance from said first end to said fourth end to a second distance from said first end to said second end being between 0.91 and 0.93;
wherein said ports being kidney-shaped;
wherein said kidney-shaped ports having a width and a ratio of a depth of said kidney-shaped port, to said width is between 0.48 and 0.62;
wherein a wear plate is affixed to said second end of said cylindrical body portion; and
wherein said wear plate having ports aligned with said ports in said cylindrical body.

5. The integrated drive generator as set forth in claim 1 , wherein said wear plate is formed of a lead-free bronze.

6. The integrated drive generator as set forth in claim 5 , wherein said lead-free bronze is ASTM B505, alloy C90700.

7. The integrated drive generator set forth in claim 4 , wherein there are a pair of said hydraulic units.

8. A method of replacing a cylinder block in an integrated drive generator comprising the steps of:
removing an existing cylinder block from an integrated drive generator including an input shaft connected for driving a differential, said differential for providing an input drive to a generator for generating electricity, and said differential also being connected with hydraulic unit, said hydraulic unit including a variable swash plate and a fixed swash plate, and each of said swash plates being associated with a set of pistons, said existing cylinder block being one of a pair of cylinder blocks with one of said cylinder blocks being associated with each of said sets of pistons;
replacing said existing cylinder block with a replacement cylinder block, said replacement cylinder block having a shaft portion with a relatively small outer diameter and a cylindrical body portion having a larger outer diameter than the shaft portion, and said cylindrical body portion formed with a plurality of piston chambers, said cylindrical body portion extending from a first end to a second end, said second end being provided with ports leading into said piston chambers and said ports having a third end and a fourth end wherein a ratio of a first distance from said first end to said fourth end to a second distance from said first end to said second end being between 0.91 and 0.93;
wherein said ports being kidney-shaped;
wherein said kidney-shaped ports having a width and a ratio of a depth of said kidney-shaped port, to said width is between 0.48 and 0.62;
wherein a wear plate is affixed to said second end of said cylindrical body portion; and
wherein said wear plate having ports aligned with said ports in said cylindrical body.

9. The method of replacing a cylinder plate as set forth in claim 8 , wherein said wear plate is formed of a lead-free bronze.

10. The method of replacing a cylinder plate set forth in claim 8 , wherein there are a pair of said hydraulic units.

Assignees

• Hamilton Sundstrand Corp

Inventors

• Hochstetler Derek R
• Martin Ted A
• Johnson Duane C
• Lemmers Jr Glenn C

Classifications

• F03C1/0647

  Particularities in the contacting area between cylinder barrel and valve plate · CPC title

• F04B1/2021

  characterised by the contact area between cylinder barrel and valve plate · CPC title

• F04B1/2035

  Cylinder barrels · CPC title

• F03C1/0652

  Cylinders · CPC title

• F01B3/0085

  Pistons · CPC title