LOCKOUT APPARATUS FOR PROTECTING AN ATTACHMENT DEVICE MOUNTED ON ROTARY POWER TOOLS

• US 20110186322A1
• Filed: 02/04/2010
• Published: 08/04/2011
• Est. Priority Date: 02/04/2010
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH, Robert Bosch Tool Corporation (Robert Bosch GmbH)
• Original Assignee: Credo Technology Corporation (Robert Bosch GmbH), Robert Bosch GmbH
• Inventors: Wasielewski, Kevin
• Granted Patent: US 8,312,936 B2
• Time in Patent Office: Days
• US Class Current: 173/213
• CPC Class Codes: B25F 3/00 Associations of tools for different working operations with one portable power-drive means; Adapters therefor
• CPC Class Codes: B25F 5/00 Details or components of portable power-driven tools not particularly related to the operations performed and not otherwise provided for

Abstract

A power hand tool comprising an elongated housing with a nose portion having an opening concentric with a rotary output shaft, the nose portion being configured to have an accessory device mounted thereon, a shaft lock mechanism including a shaft lock actuator that is located at least adjacent to or on the nose portion and is configured to be moved by a user to engage the output shaft and prevent rotation thereof, the actuator being configured to be disabled from movement to engage the output shaft when an accessory device is mounted on the nose portion.

Claims

1. A power hand tool comprising:

an elongated housing with a nose portion having an opening concentric with a rotary output shaft, said nose portion being configured to have an accessory device mounted thereon;

a shaft lock mechanism including a shaft lock actuator that is located at least adjacent to or on said nose portion and is configured to be moved by a user to engage said output shaft and prevent rotation thereof;

said actuator being configured to be disabled from movement to engage said output shaft when an accessory device is mounted on said nose portion.

2. A power hand tool as defined in claim 1 wherein said nose portion includes a transition portion with an inclined outer surface extending radially inwardly toward the output shaft and a generally cylindrically shaped wall extending from said transition portion concentrically and forwardly and having a plurality of screw threads formed in an outer surface of said wall configured to have said attachment device with a screw threaded collar mounted on said nose portion, wherein the collar is screwed onto said nose portion to secure the same thereto.

3. A power hand tool as defined in claim 2 wherein said shaft lock actuator comprises a pushbutton located generally coextensive with said transition portion, wherein said pushbutton is configured to be moved inwardly toward said output shaft into engagement therewith.

4. A power hand tool as defined in claim 3 wherein said pushbutton has a surface extending forwardly in a direction generally parallel to said output shaft positioned to contact an end portion of the screw threaded collar of the attachment device is mounted on said nose portion and prevent said pushbutton from being moved inwardly into engagement with said output shaft.

5. A power hand tool as defined in claim 4 wherein said surface comprises a rib located on said pushbutton configured and designed to contact said end portion of said collar.

6. A power hand tool as defined in claim 5 wherein the attachment device has an input shaft that connects with said output shaft of said hand tool, and the attachment further comprises a second shaft lock mechanism for locking said input shaft of the attachment device.

7. A lockout device for a hand held power hand tool that has an elongated housing with a nose portion having an opening concentric with a rotary output shaft, with the nose portion being configured to have an accessory device mounted thereon, the hand tool having a shaft lock mechanism including a shaft lock actuator that is located at least adjacent to or on the nose portion configured to be moved by a user and cause the shaft lock mechanism to engage said output shaft and prevent rotation thereof, said lockout device comprising:

said actuator having a surface extending forwardly in a direction generally parallel to the output shaft positioned to contact a portion of the attachment device when the attachment device is mounted on the hand tool and prevent said actuator from being moved to cause the shaft lock mechanism to engage said output shaft and prevent rotation thereof.

8. A lockout device as defined in claim 7 wherein said actuator comprises a pushbutton configured to be moved inwardly toward the output shaft into engagement therewith.

9. A lockout device as defined in claim 8 wherein said pushbutton has said surface extending forwardly in a direction generally parallel to the output shaft positioned to contact an end portion of a screw threaded collar of the attachment device when the attachment device is mounted on the hand tool and prevent said pushbutton from being moved inwardly into engagement with the output shaft.

10. A lockout device as defined in claim 9 said surface comprises a rib located on said pushbutton configured and designed to contact the end portion of the collar.

11. A method of protecting a flexible drive portion of a drive interconnection between an output shaft of a rotary power tool and an input shaft of an accessory device that also has an output shaft that is configured to be mounted on the power tool, wherein the power tool and the accessory device each have respective shaft lock mechanisms that are actuated by being moved into locking engagement by a user for preventing rotation of their respective output shafts, said method comprising:

providing a extension on the power tool shaft lock mechanism that is designed and configured to be in close proximity to the accessory device when the accessory device is mounted on the power tool, so that the extension prevents actuation of the power tool shaft lock mechanism.

12. A method as defined in claim 11 wherein the shaft lock mechanism of the power tool comprises a pushbutton that is depressed by a user into locking engagement with the power tool output shaft.

13. A method as defined in claim 12 wherein said pushbutton has an rib extending to a location adjacent the accessory device when the accessory device is mounted on the power tool, so that the pushbutton is precluded from being depressed by the accessory device.