Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.


  1. Advanced Patent Search
Publication numberUS551052 A
Publication typeGrant
Publication dateDec 10, 1895
Filing dateJan 30, 1895
Publication numberUS 551052 A, US 551052A, US-A-551052, US551052 A, US551052A
InventorsWaldron Siionnard
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
US 551052 A
Abstract  available in
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

(No Model.)


SELF OPENING POCKET KNIFE. No. 551,052. 7 Patented Dec. 10, 1895.





SPECIFICATION forming part of Letters Patent No. 551,052, dated December 10, 1895.

Application filed January 30, 1896.

To all whom it may concern.-

Be it known that we, HAROLD WALDRoN SHONNARD and GEORGE HowLETr DAVIS, citizens of the United States, residing at New York, in the county of New York and State of New York, have invented a certain new, useful, and valuable Improvement in Self- Opening Pocket-Knives, of which the following is a full, clear, and exact description.

Our invention relates to selfopening pocketknives, and has for its object to provide the combination and arrangement of parts, substantially as shown in the accompanying drawings, and such as will be hereinafter fully described.

In said drawings, Figure 1 is a side elevation of the improved knife having one lining side removed. Fig. 2 is a detailed view of the lining referred to as removed from Fig. 1. Fig. 3 is a detail view showing the releasing mechanism in position on the lining. Fig. 4 is a longitudinal section taken substantially through the center of the knife and showing its several parts in operative positions. Fig. 5 is a detail View of the releasing-lever. Fig. 6 is a detail view of the locking-spring. Fig. 7 illustrates a modified form of actuatingspring employed with the releasing device shown in Figs. 1 to 6, inclusive.

In the following detailed description like numerals of reference indicate corresponding parts throughout the several views.

The blade 1, having the tang 2, is pivotally secured between the linings 3 4 by the rivet 5, which also passes through the bolsters 6 6.

It will be observed that the tang 2 of the blade, as shown at Figs. 1 and 2, is camshaped-t'. 6., its periphery at the point 8 is farther removed from the pivot 5'than at the point 7--and the purpose of this is to allow the blade or tang at the point 8 to be free of the end 9 of the back spring 10 when said blade is closed, thus permitting the actuating-spring 11 togive the blade a free quick start the moment it is released. The stop-pin 12 prevents the end 9 of the back spring from contacting with the tang of the blade until the latter has opened to a considerable extent and attained amomentum, when the said end 9 comes in frictional contact with said tang 2 at about the point 8, and upon the blade being Serial No. 536,646. (No model.)

completely opened the said end 9 rests on the flattened part 13 of said tang.

The device for releasing and locking the blade of the form shown at Figs. 1 to 6, inelusive, consists, essentially, of the lining 4, having the slot 14, the pivot-hole 15, and the pin-hole 16. The edge 17 of the slot 14 serves as a fulcrum for the releasing-lever 18, which extends through said slot 14 and engages the locking-spring 19 near its locking-pin 20,

which is normally kept pressed against the tang 2 and enters either of the holes 21 22, when they are thrown into properposition by the opening or closing of the blade, and'can only be freed therefrom when the button 23 of the releasing-lever 18 is pushed inward, which causes its opposite end 24 to press the end of the locking-spring 19, carrying the pin 20, outward, and thus allowing the spring 11, assuming the blade to have been closed, to quickly throw the said blade completely or partly open. WVhen the blade is closed, the hole 22 is engaged, and when opened full-way the oppositely-arranged hole 21 is engaged by said pin 20. The locking-spring having the slot 25, through which the releasing-lever 18 passes, is rigidly secured in any suitable manner at the point 26, so as to keep its free end and the pin 20 pressed inward. As is obvious, the button 23 extends through an opening in the side of the knife, so as to allow it to be readily operated by the thumb or finger.

In the modification shown at Fig. 7 the actuating device consists of the cord 35, attached to the tang at point 36 and normally exerting a tension thereon by the coil-spring 37. The releasing device shown at Figs. 1 to 6 is preferably employed with this form of actuating device.

Many minor changes may be made Without departing from the spirit of our invention, as

What we claim is- 1. In a knife, the combination with the pivoted, spring-actuated blade,of a slotted spring having one end secured to the knife lining and its other end provided with a stud adapted to engage holes in the blade, and a lever passing through the slotted spring and lining and adapted when depressed to release the stud from engagement with the blade, substantially as described.

ted spring and fulcrulned upon the lining, and a button upon the outer end of the lever, I

said button when depressed serving to force the inner end of the lever outward against the slotted spring whereby the stud upon the latter is freed from engagement with the I and the other end carried through the side of blade, as and for the purpose set forth.

3. In a knife, the combination with the spring actuated blade provided with looking holes and a cam-faced tang, of a spring frictionally acting upon said tang, a slottedspring secured to the knife-lining and having a stud at its free end adapted to engage the locking holes in the blade and lock the latter in its closed and open position, and a lever passing j through the slotted spring and fulcrumed' upon the lining and adapted when depressed to free the stud from engagement with the locking holes in the blade, substantially as described.

4. In a self opening knife, the combination with the blade having one or more lock holes therein, a suitable spring adapted to keep said blade normally open, a fiat spring carrying a stud adapted to engage said holes, a lever passing through an opening in the lining and fulcrunied thereon, one end of said lever engaging the flat spring near the stud the knife so as to be convenientlypressed, as and for the purpose set forth.

In testimony whereof we affix our signatures in presence of two witnesses.


L. D. SMITH, F. H. Wis-GIN.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4719700 *Jun 26, 1986Jan 19, 1988Taylor Jr William JKnife opening mechanism
US6145202 *Jun 11, 1998Nov 14, 2000Kai U.S.A. Ltd.Opening and closing assisting mechansim for folding knife
US6338431Jan 14, 2000Jan 15, 2002Kai U.S.A. Ltd.Locking knife blade with moving locking mechanism on blade
US6378214Jun 8, 2000Apr 30, 2002Kai U.S.A. Ltd.Locking knife blade with moving locking mechanism on blade
US6397476 *Aug 25, 2000Jun 4, 2002Kai U.S.A. Ltd.Opening and closing assisting mechanism for a folding knife
US6438848Sep 25, 2000Aug 27, 2002Mentor Group LlcFolding tool with a lock and automatic opener
US6460433Oct 16, 1998Oct 8, 2002C-Tech AgMultipurpose hand device
US6779425Jul 16, 2002Aug 24, 2004Ctech AgMultipurpose handheld implement
US6941604Aug 28, 2003Sep 13, 2005Ctech AgMultipurpose hand-held implement of the pocket-knife type
US6941661Aug 8, 2002Sep 13, 2005Spencer FrazerFolding knife
US6948409Aug 23, 2004Sep 27, 2005Ctech AgMultipurpose handheld implement
US6959494Oct 7, 2003Nov 1, 2005Camillus Cutlery CompanyFolding blade knife with spring assisted pivoting feature
US7080457Jun 10, 2003Jul 25, 2006Scott SullivanSpring assisted folding knife
US7086157Jul 31, 2002Aug 8, 2006The Great American Tool Company Inc.Folding knife having a biased blade
US7107686Feb 6, 2004Sep 19, 2006Buck Knives, Inc.Spring assist knife
US7140110Jun 4, 2004Nov 28, 2006Lake Ronald WFolding knife having a locking mechanism
US7296355Oct 12, 2004Nov 20, 2007Kai U.S.A., Ltd.Adjustable blade-assisting mechanism for a folding knife
US7313866Jan 31, 2006Jan 1, 2008Buck Knives, Inc.Spring assist knife
US7337486Apr 25, 2006Mar 4, 2008Leatherman Tool Group, Inc.Hand tool
US7340838Jun 16, 2003Mar 11, 2008Kai U.S.A., Ltd.Folding knife with safety lock
US7395599Nov 18, 2004Jul 8, 2008Kai U.S.A., Ltd.Blade-assisting mechanism for a folding knife
US7458159Nov 14, 2005Dec 2, 2008Kai U.S.A., Ltd.Folding knife having a locking mechanism
US7506446Apr 16, 2004Mar 24, 2009Kai U.S.A., Ltd.Locking mechanism for a folding knife
US7543386May 8, 2006Jun 9, 2009Sullivan Scott LSpring assisted folding knife
US7676931Jun 14, 2005Mar 16, 2010Leatherman Tool Group, Inc.Folding knife
US7774939Jan 28, 2005Aug 17, 2010Kai U.S.A., Ltd.Stud-lock knife
US8001693Jun 5, 2006Aug 23, 2011Onion Kenneth JClosable knife with opening mechanism
US8161653Nov 12, 2007Apr 24, 2012Leatherman Tool Group, Inc.Folding tool having a rotatable locking mechanism
US8307555May 3, 2011Nov 13, 2012Onion Kenneth JClosable knife with opening mechanism
US8893389May 31, 2011Nov 25, 2014Fiskars Brands, Inc.Cantilever spring assist knife
US8939053 *Aug 27, 2012Jan 27, 2015Joseph R. PardueAssisted opening mechanism for a folding knife
US20140053409 *Aug 27, 2012Feb 27, 2014Joseph R. PardueAssisted Opening Mechanism for a Folding Knife
DE1013198B *Apr 21, 1956Aug 1, 1957C Friedr Ern FaMesser mit durch Federwirkung aus der Einklapp- in die Gebrauchsstellung klappbarer Klinge
Cooperative ClassificationB26B1/046