Downhole power drilling tool having multi-stage dual plunger eccentric gear mechanism

Patent metadata

Field	Value
Publication number	US-11598151-B2
Application number	US-202117331646-A
Country	US
Kind code	B2
Filing date	May 27, 2021
Priority date	Oct 22, 2019
Publication date	Mar 7, 2023
Grant date	Mar 7, 2023

Abstract

A downhole power drilling tool includes a flow distribution shaft, an outer pipe and a multi-stage eccentric gear driving mechanism which are coaxially arranged, the flow distribution shaft is suspended and supported in the outer pipe by the multi-stage eccentric gear driving mechanism.

First claim

What is claimed is:

1. A downhole power drilling tool, comprising:
a flow distribution shaft,
an outer pipe, and
a plurality of eccentric gear driving mechanisms which are coaxially arranged, wherein the flow distribution shaft is suspended and supported in the outer pipe by the plurality of eccentric gear driving mechanisms;
each of the plurality of eccentric gear driving mechanisms defining a stage and comprising:
a planetary gear train, and
plunger driving structures symmetrically arranged on two axial end faces of the planetary gear train;

wherein two pairs of planetary gears which are symmetrically distributed are arranged on a planetary carrier of the planetary gear train, a gear ring of the planetary gear train is in an interference fit with the outer pipe; each of the plunger driving structures comprises a mounting block, a through hole is formed in a center of the mounting block, and an inner diameter of the through hole is the same as an inner diameter of a sun gear of the planetary gear train; four plunger passages are formed in a radial direction of the mounting block, and the four plunger passages are uniformly distributed around the center of the mounting block; each of the four plunger passages is filled with a plunger in a sliding fit; a guide post is integrally formed in a wall of the plunger, an axial direction of the guide post is the same as an axial direction of the flow distribution shaft, and a guide groove is formed at a position corresponding to the guide post of a corresponding one of the four plunger passages; the guide groove facing one side of the planetary gear train is a through groove, and the guide post extends through the through groove to be in eccentric connection with one of the two pairs of planetary gears on the planetary gear train; and
wherein one end of the flow distribution shaft is open, a second end of the flow distribution shaft is closed, and an inner cavity of the flow distribution shaft is a flow distribution passage; the plurality of eccentric gear driving mechanisms are arranged on the flow distribution shaft at intervals in the axial direction of the flow distribution shaft, the sun gear is keyed onto the flow distribution shaft; four rows of water inlet ports and four rows of water outlet grooves are uniformly and circumferentially formed in the flow distribution shaft, the water inlet ports are in fluid communication with the flow distribution passage, the water inlet ports and the water outlet grooves in each row are spaced apart from each other, and an angular difference between the water inlet ports and the water outlet grooves in adjacent rows is 45°; an angular difference between eccentric gear driving mechanisms of the plurality of eccentric gear driving mechanisms in two adjacent stages is 45°, and when the four plunger passages of one stage are in fluid communication with the water inlet ports on the flow distribution shaft, the four plunger passages of an adjacent stage are in fluid communication with the water outlet grooves.

2. The downhole power drilling tool according to claim 1 , wherein each of the water inlet ports is an oblong hole or an elliptical hole, and each of the four plunger passages has an opening which is a circular hole, and a projection of the oblong hole or the elliptical hole is inscribed in the circular hole.

3. The downhole power drilling tool according to claim 2 , wherein one end of the outer pipe corresponding to an opening of the flow distribution shaft is connected with a connector, and a second end of the outer pipe is connected with a retainer ring; the downhole power drilling tool further comprises a spindle, wherein the spindle is disposed in the retainer ring and is connected to the second end of the flow distribution shaft, and the spindle is supported in the retainer ring via a bearing.

4. The downhole power drilling tool according to claim 3 , wherein the water outlet grooves communicate with a spindle passage.

5. The downhole power drilling tool according to claim 4 , wherein the one end of the flow distribution shaft connected to the spindle extends outwards to form a regular polygonal plug, and one end of the spindle passage facing the flow distribution shaft is formed with a corresponding regular polygonal plug receptacle.

6. The downhole power drilling tool of claim 5 , wherein each of the water outlet grooves extends to a side wall of the regular polygonal plug and forms a water passing gap at a mating surface of the regular polygonal plug and the corresponding regular polygonal plug receptacle.

7. The downhole power drilling tool according to claim 3 , wherein an end of the retainer ring is arranged with an end face seal.

8. The downhole power drilling tool according to claim 1 , wherein each of the water inlet ports is a circular hole, and each of the four plunger passages has an opening which is an oblong hole or an elliptical hole, and a projection of the oblong hole or the elliptical hole is inscribed in the circular hole.

9. The downhole power drilling tool according to claim 1 , wherein supporting structures are respectively arranged between two adjacent stages, and the supporting structures are fixedly connected to the flow distribution shaft, and are rotatably fitted to the outer pipe.

Assignees

• Univ China Geosciences Beijing

Inventors

• Wang Yu
• Lu Jiaxing
• Wang Zhiqiao
• Liu Baolin
• Zhou Qin
• Chang Tengteng

Classifications

• F03C1/2446

  cylinder block and actuated cam both rotating · CPC title

• F03C1/26

  adapted for special use or combined with apparatus driven thereby · CPC title

• E21B4/006 Primary

  Mechanical motion converting means, e.g. reduction gearings (E21B4/10 takes precedence) · CPC title

• F03C1/08

  Distributing valve-gear peculiar thereto (for engines with positive-displacement in general F01L; {F03C1/06 takes precedence}) · CPC title

• F03C1/002

  details; components parts · CPC title