公开(公告)号：US20230124502A1

公开(公告)日：2023-04-20

申请号：US17503006

申请日：2021-10-15

申请人： Caterpillar Inc.

发明人： Curtis Andrew Henning ,  Cody Moore ,  Michael Alan Pershing ,  Robert Jason Pickerill

IPC分类号： B25D9/12 ,  F16F13/14 ,  C21D9/00

摘要： An example bushing of a hydraulic hammer tool includes an outer region and an inner region. The inner region has a relatively greater hardness than the outer region. The inner region may also be compressively stressed, while the outer region may have tensile stress. The stress and/or hardness profile of the bushing may enhance its resistance to wear and galling defects when a hammer of the hydraulic hammer tool is held in alignment by the bushing. The outer region of the bushing may be relatively soft, resulting in the bushing having a relatively high level of toughness. The bushing may be formed using medium to high carbon steel by rough forming the bushing, hardening the bushing, tempering the bushing, and induction softening the outer region of the bushing.

公开(公告)号：US20220412406A1

公开(公告)日：2022-12-29

申请号：US17358430

申请日：2021-06-25

申请人： Caterpillar Inc.

发明人： Cody Moore ,  Curtis Andrew Henning ,  Michael Alan Pershing ,  Robert Jason Pickerill

IPC分类号： F16C33/64 ,  F16C33/66

摘要： An example bushing of a hydraulic hammer tool includes a bulk region and an inner region. The inner region has a relatively greater hardness than the bulk region. The inner region may also be compressively stressed, while the bulk region may have tensile stress. The stress and/or hardness profile of the bushing may enhance its resistance to wear and galling defects when a hammer of the hydraulic hammer tool is held in alignment by the bushing. The bulk region of the bushing may be relatively soft, resulting in the bushing having a relatively high level of toughness. The bushing may be formed using medium to high carbon steel by rough forming the bushing, hardening the bushing, tempering the bushing, induction hardening the inner region of the bushing, and then quenching the inner region.