Handheld punch tool

Patent metadata

Field	Value
Publication number	US-11820038-B2
Application number	US-202117500506-A
Country	US
Kind code	B2
Filing date	Oct 13, 2021
Priority date	Oct 14, 2020
Publication date	Nov 21, 2023
Grant date	Nov 21, 2023

Abstract

A handheld punch tool includes a housing, a die holder coupled to the housing, a die supported by the die holder, the die and the die holder defining a feed slot therebetween for receiving a workpiece to be cut, and a punch configured to reciprocate within the die holder, with a main body defining a first longitudinal axis extending centrally through the main body and a punch element extending from the main body along a second longitudinal axis parallel to the first longitudinal axis. The punch element is configured to cut a first distance into the workpiece per stroke of the punch when the feed slot faces a first side of the punch and to cut a second distance into the workpiece per stroke when the feed slot faces a second side of the punch opposite the first side. The first distance is greater than the second distance.

First claim

What is claimed is:

1. A handheld punch tool comprising:
a housing;
a die holder coupled to the housing;
a die supported by the die holder, the die and the die holder defining a feed slot therebetween for receiving a workpiece to be cut; and
a punch configured to reciprocate within the die holder, the punch including a main body defining a first longitudinal axis extending centrally through the main body and a punch element extending from the main body along a second longitudinal axis parallel to the first longitudinal axis,
wherein the punch element is configured to cut a first distance into the workpiece per stroke of the punch when the feed slot faces a first side of the punch,
wherein the punch element is configured to cut a second distance into the workpiece per stroke of the punch when the feed slot faces a second side of the punch opposite the first side, and
wherein the first distance is greater than the second distance.

2. The handheld punch tool of claim 1 , wherein the die holder is selectively rotatable relative to the housing between a plurality of predetermined rotational positions.

3. The handheld punch tool of claim 2 , wherein the die holder includes a plurality of notches, and wherein the punch tool further comprises a detent supported by the housing and engageable with the plurality of notches to retain the die holder in each of the plurality of predetermined rotational positions.

4. The handheld punch tool of claim 1 , wherein the punch element is cylindrical.

5. The handheld punch tool of claim 1 , wherein the die is removably coupled to the die holder.

6. The handheld punch tool of claim 1 , wherein the first distance is about 50% greater than the second distance.

7. The handheld punch tool of claim 1 , further comprising:
an electric motor disposed within the housing and having a motor shaft configured to rotate about a motor axis to reciprocate the punch along the first longitudinal axis; and
a fan coupled to the motor shaft for co-rotation therewith,
wherein the fan has a rotational inertia of at least 50% of a total rotational inertia of a rotating assembly comprising the fan, the motor shaft, and all other components of the handheld punch tool driven by the electric motor for rotation about the motor axis.

8. A handheld punch tool comprising:
a housing;
a tool element extending from the housing;
an electric motor disposed within the housing and having a motor shaft configured to rotate about a motor axis to drive the tool element; and
a fan coupled for co-rotation with the motor shaft,
wherein the fan has a rotational inertia between 40% and 60% of a total rotational inertia of a rotating assembly comprising the fan and the motor shaft.

9. The handheld punch tool of claim 8 , wherein the fan is made of zinc.

10. The handheld punch tool of claim 8 , wherein the rotation of the fan generates an airflow over the electric motor to cool the electric motor.

11. The handheld punch tool of claim 8 , wherein the fan has a rotational inertia of at least 6.0 kg-mm 2 .

12. The handheld punch tool of claim 8 , wherein the fan has a rotational inertia of at least 7.0 kg-mm 2 .

13. The handheld punch tool of claim 8 , wherein the fan includes a cylindrical base, a plate extending from the cylindrical base, and a plurality of blades extending along an axial side of the plate.

14. The handheld punch tool of claim 8 , wherein the tool element is configured to reciprocate along a tool axis perpendicular to the motor axis in response to operation of the electric motor.

15. The handheld punch tool of claim 14 , wherein the housing defines a longitudinal center axis, wherein the housing includes a battery receptacle configured to receive a battery along a battery axis to provide power to the electric motor, and wherein the battery axis, the motor axis, and the longitudinal center axis are coaxial.

16. A handheld punch tool comprising:
a housing;
a die holder coupled to the housing;
a die supported by the die holder, the die and the die holder defining a feed slot therebetween for receiving a workpiece to be cut;
a punch configured to reciprocate within the die holder along a punch axis;
an electric motor disposed within the housing and having a motor shaft configured to rotate about a motor axis to reciprocate the punch; and
a flywheel mass coupled for co-rotation with the motor shaft
wherein the flywheel mass has a rotational inertia of at least 50% of a total rotational inertia of a rotating assembly comprising the flywheel mass and the motor shaft.

17. The handheld punch tool of claim 16 , wherein the rotating assembly further comprises a fan positioned adjacent the flywheel mass.

18. The handheld punch tool of claim 17 , wherein the fan is made of plastic.

19. The handheld punch tool of claim 16 , wherein the punch includes a punch element extending from the main body along a longitudinal axis parallel to the punch axis,
wherein the punch element is configured to cut a first distance into the workpiece per stroke of the punch when the feed slot faces a first side of the punch,
wherein the punch element is configured to cut a second distance into the workpiece per stroke of the punch when the feed slot faces a second side of the punch opposite the first side, and
wherein the first distance is greater than the second distance.

20. The handheld punch tool of claim 16 , wherein the housing defines a longitudinal center axis, wherein the housing includes a battery receptacle configured to receive a battery along a battery axis to provide power to the electric motor, and wherein the battery axis, the motor axis, and the longitudinal center axis are coaxial.

Assignees

• Milwaukee Electric Tool Corp

Inventors

• Strachan Jacob C
• Boldt Benjamin J
• Zucca Gerald A

Classifications

• B23D27/04

  actuated by electric power · CPC title

• H02K7/145

  Hand-held machine tool · CPC title

• H02K7/02

  Additional mass for increasing inertia, e.g. flywheels · CPC title

• B26F1/34 Primary

  power actuated (details or components, e.g. casings, bodies, of portable power-driven tools not particularly related to the operation performed B25F5/00) · CPC title

• B21D28/02

  Punching blanks or articles with or without obtaining scrap (cutting nails or pins from strips or sheet material B21G3/26); Notching · CPC title