Utility knife

• US 6,449,850 B1
• Filed: 08/13/1999
• Issued: 09/17/2002
• Est. Priority Date: 08/13/1999
• Status: Expired due to Fees

• Current Assignee: Stanley Works Limited (Stanley Black & Decker, Inc.)
• Original Assignee: Stanley Works Limited (Stanley Black & Decker, Inc.)
• Inventors: Gilbert, Richard
• Primary Examiner(s): PAYER, HWEI SIU CHOU
• Application Number:
  US09/374,205
• Time in Patent Office: 1,131 Days
• Field of Search: 301/51, 301/62, 303/29, 303/35
• US Class Current: 30/162
• CPC Class Codes: B26B 5/001 with blades being slid out of handle immediately prior to use

Abstract

A utility knife comprises two elongate handle portions and a blade carrier assembly carrying a blade arranged to protrude from a front end of the handle. The upper handle portion has an aperture through a rear end part thereof. When the knife is assembled, the two handle portions are slid relatively longitudinally of one another, the upper handle portion moving forwardly of the lower handle portion, until a latch part near the rear end of the lower handle portion clicks into latching engagement with the front edge of the aperture in the upper handle portion. The upper handle portion is formed near its front end with interlocking elements, each having an integral, forwardly projecting piece at the bottom thereof. The front of the lower handle portion is formed with interlocking elements, each having an integral, rearwardly projecting piece at the top thereof, to overlie and hence interlock with a forwardly projecting piece at the bottom of the corresponding interlocking element of the upper handle portion. The upper portion further includes a forwardly-projecting flat tab which is received within a longitudinally-extending slot formed in the forward end of the lower handle portion.

Claims

1. A utility knife comprising:

an elongated handle having a front end and a rear end, said elongated handle defining a cavity therein and including carrier guide structure provided within said cavity, said elongated handle comprising a first plastic handle portion and a mating second plastic handle portion, each having front and rear ends corresponding to the front and rear ends of said elongated handle;

releasable locking structure associated with said first plastic handle portion and said second plastic handle portion, said releasable locking structure constructed and arranged to releasably lock said first plastic handle portion to said second plastic handle portion;

a blade carrier assembly constructed and arranged to carry a knife blade and to be manually slidable on said carrier guide structure in a longitudinal direction with respect to said elongated handle to selectively extend the knife blade outwardly from the front end of the elongated handle or retract the knife blade into said cavity;

said first plastic handle portion comprising;

first interlock structure including a pair of forwardly-extending first projections and a pair of rearwardly-extending first recesses; and

a projecting tab proximate the front end of said first plastic handle portion and extending toward the front end of said first plastic handle portion;

said second plastic handle portion comprising;

second interlock structure including a pair of rearwardly-extending second projections and a pair of forwardly-extending second recesses; and

a longitudinal slot proximate the front end of said second plastic handle portion,

said first and second plastic handle portions being constructed and arranged to be cooperatively mated with one another to form said elongated handle by longitudinally displacing said first plastic handle portion relative to said second plastic handle portion so that (i) said forwardly-extending first projections of said first interlock structure operatively engage with said forwardly-extending second recesses of said second interlock structure, (ii) said rearwardly-extending second projections of said second interlock structure operatively engage with said rearwardly-extending first recesses of said first interlock structure, and (iii) said projecting tab of said first plastic handle portion extends forwardly into said longitudinal slot formed in the front end of said second plastic handle portion,

wherein an inside surface of said projecting tab and an opposed interior surface of the longitudinal slot formed in the front end of said second plastic handle portion define an opening in the front end of the elongated handle through which said knife blade can be extended and retracted,

said releasable locking structure preventing longitudinal displacement of said first plastic handle portion relative to said second plastic handle portion thereby preventing separation of said first plastic handle portion from said second plastic handle portion, and

said releasable locking structure being releasable to enable said first and second plastic handle portions to be longitudinally displaceable relative to one another to enable (i) said forwardly-extending first projections to be longitudinally moved out of said forwardly-extending second recesses, (ii) said rearwardly-extending second projections to be longitudinally moved out of said rearwardly-extending first recesses, and (iii) said projecting tab to be longitudinally moved out of said longitudinal slot and thereby allow separation of said first and second plastic handle portions.

2. A knife as claimed in claim 1, wherein said releasable locking structure comprises an aperture formed through a rear end part of one of said first plastic handle portion and said second plastic handle portion, and a resiliently deflectable, integrally formed latch part on the other of said second plastic handle portion, said resiliently deflectable, integrally formed latch part being in the form of cantilever extending generally forwardly to protrude into said aperture, a front end of said resiliently deflectable, integrally formed latch part being in latching engagement with a front edge of said aperture and said resiliently deflectable, integrally formed latch part being biased longitudinally of the first and plastic handle portion into said latching engagement by manual pressure applied through said aperture.

3. A knife as claimed in claim 1, wherein said first and second interlock structures are integrally formed with said first and second plastic handle portions, respectively.

4. A knife as claimed in claim 1, wherein said first and second interlock structures include an opposed longitudinally projecting member and complementary recess on opposite handle portions that cooperate upon relative longitudinal movement of said handle portions to retain and release the locking engagement between said portions.