Cordless tool system

• US 8,963,497 B2
• Filed: 02/27/2012
• Issued: 02/24/2015
• Est. Priority Date: 03/08/2011
• Status: Active Grant

• Current Assignee: Chervon (HK) Limited (Chervon Holdings Limited)
• Original Assignee: Chervon (HK) Limited (Chervon Holdings Limited)
• Inventors: Yang, Dezhong, Zhang, Qichun, Xu, Haishen, Duan, Junya, Du, Hao
• Primary Examiner(s): Muralidar, Richard V
• Assistant Examiner(s): HENZE-GONGOLA, DAVID V
• Application Number:
  US13/405,700
• Publication Number:
  US 20120227994A1
• Time in Patent Office: 1,093 Days
• Field of Search: 320/114, 320/112, 320/113
• US Class Current: 320/113
• CPC Class Codes: A01D 2101/00 Lawn-mowers
• CPC Class Codes: A01D 34/00 Mowers combined with apparatus performing additional operations while mowing A01D37/00 - A01D41/00, A01D43/00; convertible to apparatus for purposes other than mowing or capable of performing operations other than mowing A01D42/00; Mowing apparatus of harvesters
• CPC Class Codes: A01D 69/02 electric
• CPC Class Codes: G01K 13/00 Thermometers specially adapted for specific purposes
• CPC Class Codes: G01K 7/01 using semiconducting elements having PN junctions G01K7/02, G01K7/16, G01K7/30 take precedence
• CPC Class Codes: H02J 7/0013 acting upon several batteries simultaneously or sequentially H02J7/1423 takes precedence

Abstract

A tool discharges one battery pack and a charger simultaneously charges another battery pack to provide for continuous and circular operation of the tool. The ratio of the discharging time to the charging time is approximately 25:35.

Claims

1. A cordless tool system, comprising:

a tool;

a lithium based battery pack for supplying power to the tool; and

a heat absorbing device operably coupled to the lithium based battery pack, wherein the heat absorbing device comprises a phase-change material, the phase-change material comprising a mixture of 80%-90% sodium acetate, 1%-5% sodium dodecyl benzene sulfonate, 1%-5% carboxymethyl cellulose, and 1%-5% sodium carbonate, wherein the tool has a power of equal to or more than 300 W, and wherein the ratio of discharging time to charging time of the lithium based battery pack is approximately 25;

35.

2. The cordless tool system as recited in claim 1, comprising an intelligent charger for releasably receiving and charging the lithium based battery pack.

3. The cordless tool system as recited in claim 2, wherein the tool has an average working current of equal to or more than 12 A.

4. The cordless tool system as recited in claim 2, wherein the intelligent charging system charges the lithium based battery pack to one of a fully charged state and a storage state.

5. The cordless tool system as recited in claim 2, wherein the intelligent charging system charges the lithium based battery pack with a charging current of approximately 8 A.

6. The cordless tool system as recited in claim 1, wherein the lithium based battery pack has a battery capacity of approximately 4 Ah.

7. The cordless tool system as recited in claim 1, wherein the tool comprises a mower.

8. The cordless tool system as recited in claim 7, wherein a discharging time of the lithium based battery pack when used to power the mower is approximately 30 minutes.

9. The cordless tool system as recited in claim 1, wherein the lithium based battery pack is removeably attachable to the tool.

10. The cordless tool system as recited in claim 1, comprising a temperature measuring device associated with the lithium based battery pack.

11. The cordless tool system as recited in claim 10, wherein the temperature measuring device comprises at least one electronic element with a PN junction.

12. The cordless tool system as recited in claim 10, wherein the temperature measuring device comprises at least one triode.

13. A cordless tool system, comprising:

a tool;

a lithium based battery pack for supplying power to the tool; and

a heat absorbing device operably coupled to the lithium based battery pack, wherein the heat absorbing device comprises a phase-change material, the phase-change material comprising a mixture of 80%-90% sodium acetate, 1%-5% sodium dodecyl benzene sulfonate, 1%-5% carboxymethyl cellulose, and 1%-5% sodium carbonate, wherein the tool has a power of equal to or more than 300 W and an average working current of equal to or more than 12 A, and wherein the lithium based battery pack has a nominal voltage of equal to or more than 56V.

14. A cordless tool system, comprising:

a tool;

a lithium based battery pack for supplying power to the tool; and

a heat absorbing device operably coupled to the lithium based battery pack, wherein the heat absorbing device comprises a phase-change material, the phase-change material comprising a mixture of 90%-99% polyethylene glycol and 1%-10% cda cellulose diacetate, wherein the tool has a power of equal to or more than 300 W, and wherein the ratio of discharging time to charging time of the lithium based battery pack is approximately 25;

35.