Electrofusion tool

Patent metadata

Field	Value
Publication number	US-2025340021-A1
Application number	US-202519194587-A
Country	US
Kind code	A1
Filing date	Apr 30, 2025
Priority date	May 2, 2024
Publication date	Nov 6, 2025
Grant date	—

Abstract

An electrofusion tool used in joining pipe ends of plastic pipes together via a pipe fitting during an electrofusion process includes a housing, a battery receptacle to selectively receive a rechargeable battery pack, and electrical leads extending from the housing and configured to transfer a current from the battery pack to the pipe fitting for permanently joining the pipe ends together. The electrofusion tool also includes an electronic control unit configured to initiate a first system pre-check to determine whether an estimated peak operating current is less an output capacity of the electrofusion tool, a second system pre-check to determine whether an estimated electrical energy of the battery pack is less than a remaining charge capacity of the battery pack, and a third system pre-check to determine whether an estimated operating temperature of the battery pack is less than a set temperature threshold of the battery pack.

First claim

What is claimed is:

1 . An electrofusion tool used in joining pipe ends of plastic pipes together via a pipe fitting during an electrofusion process, the electrofusion tool comprising:
a housing; a battery receptacle to selectively receive a rechargeable battery pack; electrical leads extending from the housing and configured to transfer a current from the battery pack to the pipe fitting for permanently joining the pipe ends together; and an electronic control unit configured to execute one or more steps, prior to initiating the electrofusion process, selected from a group consisting of:
a first system pre-check to determine whether an estimated peak operating current is less than an output capacity of the electrofusion tool,
a second system pre-check to determine whether an estimated electrical energy of the battery pack is less than a remaining charge capacity of the battery pack, and
a third system pre-check to determine whether an estimated operating temperature of the battery pack is less than a set temperature threshold of the battery pack.

2 . The electrofusion tool of claim 1 , wherein the battery pack supplies electrical current to the pipe fitting via the electrical leads when the first system pre-check, the second system pre-check, and the third system pre-check are satisfactory.

3 . The electrofusion tool of claim 1 , further comprising a scanner operable to scan the pipe fitting to obtain pipe fitting characteristics indicative of performance metrics for completing the electrofusion process.

4 . The electrofusion tool of claim 3 , wherein the first system pre-check includes the steps of
measuring a resistance of the pipe fitting by applying an electrical current to the pipe fitting and measuring a voltage drop across the electrical leads, dividing a voltage specified from the pipe fitting characteristics by the resistance of the pipe fitting to obtain the estimated peak operating current, and comparing the estimated peak operating current to the output capacity of the electrofusion tool.

5 . The electrofusion tool of claim 4 , wherein the first system pre-check fails when the estimated peak operating current is greater than the output capacity of the electrofusion tool.

6 . The electrofusion tool of claim 3 , wherein the second system pre-check includes the steps of
obtaining a remaining charge capacity of the battery pack, calculating an estimated electrical energy required to complete the electrofusion process based on the pipe fitting characteristics of the pipe fitting, and comparing the remaining charge of the battery pack with the estimated electrical energy.

7 . The electrofusion tool of claim 6 , wherein the second system pre-check fails when the estimated electrical energy is greater than the remaining charge capacity of the battery pack.

8 . The electrofusion tool of claim 6 , further comprising a voltage sensor to obtain the remaining charge capacity of the battery pack.

9 . The electrofusion tool of claim 3 , wherein the third system pre-check includes the steps of
estimating the operating temperature of the battery pack required to complete the electrofusion process based on the pipe fitting characteristics of the pipe fitting, comparing the estimated operating temperature of the battery pack with the set temperature threshold, and comparing the set temperature threshold with the estimated operating temperature of the battery pack.

10 . The electrofusion tool of claim 9 , wherein the third system pre-check fails when the estimated operating temperature is greater than the set temperature.

11 . The electrofusion tool of claim 9 , wherein the step of estimating the operating temperature of the battery pack is based on a present temperature of the battery pack and the pipe fitting characteristics of the pipe fitting required to complete the electrofusion process.

12 . The electrofusion tool of claim 11 , further comprising a temperature sensor to determine a present temperature of the battery pack, wherein the electronic control unit stops the electrofusion process when the present temperature of the battery pack becomes greater than the set temperature threshold.

13 . A method of operating an electrofusion tool to join pipe ends of plastic pipes together via a pipe fitting during an electrofusion process, the method comprising:
coupling a battery pack to the electrofusion tool; connecting electrical leads from the electrofusion tool to the pipe fitting; scanning the pipe fitting to obtain pipe fitting characteristics; and executing, by an electronic control unit of the electrofusion tool and prior to initiating the electrofusion process, one or more steps selected from a group consisting of:
a first system pre-check to determine whether an estimated peak operating current is less than an output capacity of the electrofusion tool,
a second system pre-check to determine whether an estimated electrical energy of the battery pack is less than a remaining charge capacity of the battery pack, and
a third system pre-check to determine whether an estimated operating temperature of the battery pack is less than a set temperature threshold of the battery pack.

14 . The method of claim 13 , further comprising supplying electrical current from the battery pack to the pipe fitting via the electrical leads in response to the first system pre-check, the second system pre-check, and the third system pre-check being satisfactory.

15 . The method of claim 13 , further comprising calculating the estimated peak operating current by determining a resistance of the pipe fitting by applying an electrical current to the pipe fitting and measuring a voltage drop across the electrical leads, and then dividing a voltage specified from the pipe fitting characteristics by the resistance of the pipe fitting.

16 . The method of claim 13 , further comprising calculating the estimated electrical energy to complete the electrofusion process by using the pipe fitting characteristics obtained from scanning the pipe fitting.

17 . The method of claim 13 , further comprising calculating the estimated operating temperature by using a present temperature of the battery pack and an electrical energy required to complete the electrofusion process.

18 . The method of claim 17 , further comprising providing a temperature sensor to determine the present temperature of the battery pack.

19 . The method of claim 13 , further comprising providing a voltage sensor to determine the remaining charge capacity of the battery pack.

20 . The method of claim 13 , wherein scanning the pipe fitting includes scanning a barcode encoded with the pipe fitting characteristics.

Assignees

• Milwaukee Electric Tool Corp

Inventors

• Bertz Sam L

Classifications

• H02J7/80

  including monitoring or indicating arrangements · CPC title

• F16L47/02

  Welded joints; Adhesive joints · CPC title

• F16L11/124

  Distinguishing marks for hoses · CPC title

• H05B3/06 Primary

  Heater elements structurally combined with coupling elements or holders · CPC title

• B29C66/5221

  for forming coaxial connections, i.e. the tubular articles to be joined forming a zero angle relative to each other · CPC title