US 2017/0291317 A1 · Utility Knife With Improved Safety Features

Abstract

The present utility knife provides a uniquely improved safety mechanism that increases safety, reliability, and reduces the cost of manufacturing. A shield is locked over the blade by a strut braced between the shield and a stop within the housing. The strut is biased to the locked position by an integrally molded sinuous spring that is designed to force the strut into engagement with the stop and to force the shield to cover the blade, allowing just one cut per actuator pull. The stop structure checks the motion of the strut when locked and closely guides the movement of the strut when unlocked through use of an L-shaped channel. These features reduce the complexity of the safety knife and increase the reliability of the safety mechanism under rough conditions.

Claims20

Dependent claims

1) A utility knife comprising:

a housing with a blade extending from the housing, a shield retractably extending over a cutting edge of the blade, a stop fixed within the housing, and an actuator extending from the housing;
and
a strut with an integral spring extending from the strut, the integral spring forming a connection between the strut and the housing to bias the strut towards the shield and towards the stop so that the strut is biased to be braced between the shield and the stop to selectively prevent retracting of the shield;
wherein the strut is selectively moved by manual activation of the actuator to disengage the strut from the stop so that retraction of the shield is permitted to expose the cutting edge of the blade, the integral spring forcing the strut to return to engagement with the stop when the shield is yet again extended over the cutting edge of the blade so that the strut is again braced between the shield and the stop.

1 more element

13) A utility knife comprising:

a housing with a blade extending from the housing, a shield retractably extending over a cutting edge of the blade, and an actuator extending from the housing;
a stop structure is fixed within the housing, the stop structure having a channel comprising a first channel portion connected to and transverse to a second channel portion, the first channel portion comprising a stop, the first channel portion being within the plane as the second channel portion;
and
a strut with a stop engagement boss extending laterally from the strut, the stop engagement boss positioned at least partially within the channel to restrict the movement of the stop engagement boss to the channel, the strut being biased towards the shield and towards the stop to position with the stop engagement boss adjacent to the stop, so that the strut is normally braced between the shield and the stop to selectively prevent retracting of the shield;
wherein the strut is selectively moved by activation of the actuator to lift the stop engagement boss from a locked position adjacent to the stop within the first portion of the channel to alignment with the second portion of the channel in an unlocked position so that retraction of the shield is permitted, exposing the cutting edge of the blade and causing the stop engagement boss to travel within the second portion of the channel.

2 more elements

Dependencies are inferred from the claim text.

Utility Knife With Improved Safety Features

Life of this patent

Utility Knife With Improved Safety Features

Life of this patent

Abstract

Claims20