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EP-4741629-A1 - POSITIVE-DISPLACEMENT FLUID MACHINE WITH CONSTRAINED GEARSET

EP4741629A1EP 4741629 A1EP4741629 A1EP 4741629A1EP-4741629-A1

Abstract

A positive-displacement fluid machine with a constrained gear set is provided. The positive-displacement fluid machine includes multiple shafts including a single drive shaft and multiple idler shafts. Multiple lobed rotors are provided with each mounted for rotation on one of the shafts. Each lobed rotor of the multiple of lobed rotors meshes with at least two other lobed rotors of the multiple of lobed rotors. A constrained gear set includes multiple timing gears. Each of the multiple timing gears is mounted for rotation on one of the multiple shafts. Each timing gear of the multiple timing gears intermeshes with at least two other timing gears of the multiple timing gears.

Inventors

  • ANDERSON, TYSON BENTLEY
  • HAMPSON, Daniel Todd

Assignees

  • Roper Pump Company LLC

Dates

Publication Date
20260513
Application Date
20251104

Claims (15)

  1. A positive-displacement fluid machine, comprising: a compressor chamber including multiple fluid inlets and multiple fluid outlets; a gear chamber; a plurality of shafts spanning the compressor chamber and the gear chamber, wherein the plurality of shafts includes: a drive shaft, and multiple idler shafts; a plurality of lobed rotors housed in the compressor chamber, each of the plurality of lobed rotors being mounted for rotation on one of the plurality of shafts; and a constrained gear set housed in the gear chamber, the constrained gear set including a plurality of timing gears, each of the plurality of timing gears being mounted for rotation on one of the plurality of shafts, wherein each timing gear in the plurality of timing gears intermeshes with at least two other timing gears of the plurality of timing gears.
  2. The positive-displacement fluid machine of claim 1, wherein each of the lobed rotors is identical and includes at least two lobes.
  3. The positive-displacement fluid machine of claim 1 or 2, wherein the multiple timing gears includes at least four timing gears.
  4. The positive-displacement fluid machine of any of the preceding claims, wherein the number of multiple fluid inlets is equal to the number of multiple fluid outlets.
  5. The positive-displacement fluid machine of claim 3, wherein an amount of the fluid inlets plus an amount of the fluid outlets is equal to a number of the plurality of lobed rotors.
  6. The positive-displacement fluid machine of any of the preceding claims, wherein the plurality of timing gears includes at least six timing gears.
  7. The positive-displacement fluid machine of claim 6, wherein the multiple fluid inlets include three fluid inlets.
  8. The positive-displacement fluid machine of any of the preceding claims, wherein the compressor chamber further includes an inset bar installed parallel to the shafts and through a center region of the plurality of lobed rotors.
  9. The positive-displacement fluid machine of claim 8, wherein the inset bar has a perimeter with a number of sides equal to a number of the plurality of lobed rotors.
  10. The positive-displacement fluid machine of any of the preceding claims, wherein each lobed rotor of the plurality of lobed rotors meshes with at least two other lobed rotors of the plurality of lobed rotors.
  11. The positive-displacement fluid machine of claim 10, wherein the plurality of lobed rotors do not contact each other when the plurality of lobed rotors rotate within the compressor chamber.
  12. The positive-displacement fluid machine of any of the preceding claims, further comprising: an internal wall separating the compressor chamber and the gear chamber, wherein the internal wall includes openings for the plurality of shafts to extend from the gear chamber into the compressor chamber.
  13. The positive-displacement fluid machine of any of the preceding claims, wherein each of the plurality of lobed rotors includes a circumferential-piston-style rotor.
  14. The positive-displacement fluid machine of any of the preceding claims, wherein the positive-displacement fluid machine comprises a rotary-lobe blower.
  15. The positive-displacement fluid machine of any of the preceding claims, wherein each timing gear of the plurality of timing gears includes one of: straight spur teeth, or helically oriented teeth.

Description

BACKGROUND Some positive-displacement fluid machines use rotors for their superior sealing and solids-handling capabilities. These rotors, however, cannot facilitate power transfer, and so they are externally driven by timing gears. The timing gears typically reside in a separate compartment, which is sealed off from the flow volume where the rotors and fluid reside. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic cross-section of a positive-displacement fluid machine, according to implementations described herein;Fig. 2 is a transverse cross-sectional view of a compressor chamber of a fluid machine, according to an implementation;Fig. 3 is transverse a cross-sectional view of a gear chamber of a fluid machine, according to an implementation;Figs. 4A-4C are perspective views of constrained gear sets according to different implementations;Fig. 4D is a front view of a constrained gear set with different sized gears, according to another implementation;Figs. 5A-5C are perspective views of different lobed rotor configurations driven by a four-gear constrained gear set, according to different implementations;Fig. 6 is a transverse cross-sectional view of a compressor chamber of a fluid machine, according to another implementation;Fig. 7 is a perspective view of circumferential-piston-style rotors driven by a four-gear constrained gear set, according to another implementation;Fig. 8A is a perspective view of a constrained gear set according to another implementation; andFig. 8B is a perspective view of a lobed rotor configuration according to another implementation. DETAILED DESCRIPTION The following detailed description refers to the accompanying drawings. The same reference numbers in different drawings may identify the same or similar elements. Also, the following detailed description does not limit the invention. Positive-displacement fluid machines may be used for displacing air (e.g., rotary lobe blowers) or liquids (e.g., rotary lobe pumps). In some applications, such as bulk transfer applications, positive-displacement blowers may be used for loading and unloading cargo. Transfer rates in such applications may be improved with higher suction pressures. Additionally, smaller and more maneuverable blower units may improve efficiency during transfer setup. In other applications, positive-displacement blowers may be used for pneumatic conveying (e.g., pipeline transport), aeration in water treatment, air supply in combustion systems, and other vacuum systems. In conventional blowers, the number of rotors per stage is typically limited to two, which inherently limits the suction capabilities of these machines. To increase the pressure differential across these conventional blowers, multiple stages are typically used in series. Rotary lobe pumps are sometimes used for fluids with suspended solids, high viscosity fluids, or fluids that require gentle pumping action. Similar to rotary lobe blowers, multiple stages of conventional rotary lobe pumps may be needed to achieve required pressures. Thus, there is a need for a positive-displacement fluid machine that can achieve increased pressures in a single stage, while minimizing the overall size and weight of the unit. Systems and methods described herein provide a positive-displacement machine (e.g., a rotary lobe blower or pump) with more than two rotors that are timed by a constrained gearset. In the constrained gearset, power is transmitted from a driving gear through other driven gears that connect in sequence back to the driving gear. In some aspects, there is no limit to the number of gears in the constrained system as long as the number of teeth and placement of the gears are properly matched. According to one implementation, a positive-displacement fluid machine with a constrained gear set is provided. The positive-displacement fluid machine may include multiple shafts including a single drive shaft and multiple idler shafts. Multiple lobed rotors may be included in the positive-displacement fluid machine, with each rotor mounted for rotation on a different one of the shafts. Each lobed rotor of the multiple lobed rotors may mesh with at least two other lobed rotors of the multiple lobed rotors. A constrained gear set may also be included in the positive-displacement fluid machine. The constrained gearset may include multiple timing gears. Each of the multiple timing gears may be mounted for rotation on a different one of the shafts. Each timing gear of the multiple timing gears may intermesh with at least two other timing gears of the multiple timing gears. According to implementations described herein, a positive-displacement fluid machine including a set of constrained gears and corresponding constrained rotors provides advantages of higher suction and pressure-building capabilities as compared to typical lobed blowers or pumps. The systems and methods can be applied in blowers or pumps for high suction lift and high discharge pressures, reducing