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Publication numberUS2978081 A
Publication typeGrant
Publication dateApr 4, 1961
Filing dateJul 24, 1957
Priority dateAug 13, 1956
Publication numberUS 2978081 A, US 2978081A, US-A-2978081, US2978081 A, US2978081A
InventorsEmanuel Lundin David Mauritz
Original AssigneeBahco Ab
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Devices in ratchet wrenches
US 2978081 A
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Description  (OCR text may contain errors)

April 4, 1961 D. M. E. LUNDIN DEVICES IN RATCHET WRENCHES Filed July 24; 1957 JNVENTOR DAVID MAURITZ EMANUEL LUNDIN ATTQRNEYS United States Patent nnvrcns IN RATCHET WRENCHES David Mauritz Emanuel Lundin, Enkoping, Sweden, as-

signor to Aktiebolaget Bahco, Stockholm, Sweden, a corporation of Sweden The present invention relates to a device in such ratchet wrenches wherein the operation direction of the ratchet wrench may be reversed by means of a pawl device which can be reset by hand, and the object of the invention is primarily to enable the width of the ratchet wrench head to be reduced so that the ratchet wrench can be used in very confined spaces. Furthermore, by the invention it will be possible to obtain an efficient rotating of the, work piece, usually a screw bolt, drill or the like, by very short strokes and the invention is characterized in that the pawl device comprises one or two pawl members freely journalled in a rocker pivotably carried in the wrench head, the pawl member or members being provided with, or each being provided with, respectively, one or more teeth which by self adjusting action of the pawl member are brought to engage aratchet wheel, which is associated with the engaging member of the ratchet wrench and rotatably carried in the wrench head, when the rocker is turned by hand to the position corresponding to the desired direction of operation. By this arrangement not only a very sturdy construction is obtained but, as already stated, the width of the ratchet wrench head may be highly reduced by having the ratchet wheel carried in the wrench head in such a manner that its teeth along most of the circumference are guided directly against the wrench head, due to the fact that the pawl member or members, respectively, take up very little space as viewed laterally.

The objects of the invention will be apparent when the following description is read with reference to the accompanying drawing in which:

Figure 1 shows the ratchet wrench in a perspective drawing with a part of the wrench head itself cut away. Figure 2 is a vertical, longitudinal cross-section, while Figures 3, 4 and 5 show the rocker and the pawl members set for clockwise, idling and anti-clockwise turning, respectively.

In the embodiment according to Figures 1-5, 1 denotes the wrench head and 2 the wrench handle together forming the main body of the wrench. The ratchet wheel 4, which is provided with an engaging member 3, is disposed in the head 1, the ratchet wheel rather snugly fitting the recess 5 formed in the wrench head and being carried in the same by means of the cover plates 6 and 7, detachably secured to the wrench head. Furthermore, there is in the recess 5 the rocker or carriage 11 attached to the pin 9 which is pivotable by means of the manipulator 8, the rocker in a freely rotatable manner carrying two pawl members 12 and 13 which are loosely retained in the rocker by means of a clip 14. The manipulator is retained in one or the other of its extreme positions (Figures 3 and 5) by means of a coil spring 15 in a.

2,978,081 Patented Apr. 4, 1961 manner known per se and will therefore act as a snap lock handle. As will be evident from Figure 3, the one pawl member 12 engages the ratchet wheel 4 when the manipulator 8 is turned to the left (Figure 3), and this will correspond to a clockwise rotating of the ratchet wheel 4. When the manipulator 8 is turned to the neutral position shown in Figure 4 both pawl members 12, 13 are out of engagement with the ratchet wheel 4 and when the manipulator 8 is turned to the right the pawl member 13 will engage the ratchet wheel 4 (Figure 5), this corresponding to an anticlockwise rotating of said ratchet wheel. When the member =12 as well as the member 16 engages the ratchet wheel 4 a self adjusting action takes place, as they turn in the rocker 11 in such a manner that all teeth on the pawl member operating for the time being will engage the ratchet wheel, for which reason a very strong force transmitting effect is obtained. For instance, when the pawl member 12 is in engagement with the ratchet wheel 4, which situation corresponds to a clockwise rotating of the ratchet wheel 4 when the wrench handle is turned to the left, the idling movement to the right of the wrench handle and thence the wrench head is permitted by a yielding rocking movement by the rocker 11, the position of which being controlled by the coil spring 15 received in the manipulator 8, which is deemed to be readily understood.

What is claimed is:

1. A ratchet wrench comprising a rocker, a pair of pawl members carried by said rocker, work engaging means including a rotatable ratchet wheel, each pawl having a plurality of teeth for engaging the teeth of said ratchet wheel, said rocker being pivotable between two positions in a first of which one of said pawls engages said ratchet wheel for clockwise rotation of said ratchet wheel, and in the second of which the other pawl engages said ratchet wheel for anti-clockwise rotation of said ratchet wheel, snap lock means for maintaining said rocker in a selected one of said positions, a handle for said rocker operable for selectively positioning said rocker, said pawls being mounted upon said rocker for pivotal movement relative to each other about axes parallel to the axis of said ratchet wheel for self-adjustment and full engagement of one of said pawls with said ratchet wheel when said rocker is in one of said extreme positions and full engagement of the other of said pawls with said ratchet wheel when said rocker is in the other of said extreme positions.

2. A ratchet wrench as defined in claim 1, in which a single wire retaining clip extends over the pawls and embraces the rocker for yieldably securing said pawls to said rocker.

References Cited in the file of this patent UNITED STATES PATENTS 349,007 Sinclair Sept. 14, 1886 1,209,320 Morneweck Dec. 19, 1916 1,680,515 Gormley Aug. 14, 1928 1,883,618 Dodge Oct. 18, 1932 2,542,241 Fors Feb. 20, 1951 2,711,111 Brame June 21, 1955 2,712,257 Fish July 5, 1955 OTHER REFERENCES Ser. No. 363,378, Thienes (A.P.C.), published May 4, 1943.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US349007 *Apr 10, 1880Sep 14, 1886 Ratchet-wrench
US1209320 *Jul 16, 1914Dec 19, 1916David MorneweckRatchet-wrench.
US1680515 *Dec 21, 1926Aug 14, 1928Buda CoRatchet mechanism for lifting jacks
US1883618 *May 8, 1931Oct 18, 1932Dodge John SReversible ratchet wrench
US2542241 *Oct 23, 1946Feb 20, 1951New Britain Machine CoRatchet mechanism
US2711111 *Jul 29, 1953Jun 21, 1955Tubing Appliance Company IncPower operated ratchet wrench
US2712257 *Dec 5, 1951Jul 5, 1955Tubing Appliance Co IncOpen end ratchet wrenches
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3620333 *Sep 25, 1969Nov 16, 1971Menzi Ag ErnstWheel-blocking arrangement for an excavating machine
US4068110 *Mar 23, 1976Jan 10, 1978Elektriska SvetsningsaktiebolagetMethod and apparatus for the manufacture of welded gratings
US4485700 *Jan 26, 1983Dec 4, 1984Colvin David SReversible ratchet wrench
US4531716 *Sep 12, 1983Jul 30, 1985Henry AlesRatchet puller for nails and staples
US5174176 *Dec 9, 1991Dec 29, 1992Snap-On Tools CorporationReversible rachet wrench with integrated dual pawl and spring and cam unit
US5782147 *Nov 21, 1996Jul 21, 1998Hand Tool Design CorporationRatchet wrench having two-pawl action
US5918714 *Oct 10, 1995Jul 6, 1999Keiper Recaro Gmbh & Co.Ratchet mechanism for driving adjustment devices for vehicle seats
US6161454 *Aug 20, 1998Dec 19, 2000Hand Tool Design CorporationLow cost ratchet wrench and method of assembly
US6431030 *Jul 12, 2001Aug 13, 2002Wen-Jin KuoAdjusting structure for a ratchet wrench
US6516930 *Dec 29, 2000Feb 11, 2003Ching ChenRatchet mechanism for tools
US6520051Jul 1, 2002Feb 18, 2003Bobby HuHead of a wrench handle
US6539825Sep 20, 2001Apr 1, 2003Yen-Wen LinSingle direction ratcheting wrench with stuck prevention and ratcheting direction indication
US6543316Mar 14, 2001Apr 8, 2003The Stanley WorksRatchet wrench
US6612205 *Mar 19, 2002Sep 2, 2003Darwin JonesRatchet
US6644148May 13, 2002Nov 11, 2003Bobby HuReversible ratchet-type wrench
US6647832Jul 27, 2001Nov 18, 2003Bobby HuWrench having two rigid supporting areas for a pawl
US6666112 *Jul 9, 2001Dec 23, 2003Bobby HuSwitching arrangement for a reversible ratchet type wrench
US6666117Oct 15, 2001Dec 23, 2003Bobby HuWrench with a fixed maximum operational torque
US6758641Aug 27, 2001Jul 6, 2004Bobby HuMethod for manufacturing a ratchet type ring spanner having a larger cavity for receiving a larger pawl
US6807882May 8, 2002Oct 26, 2004Bobby HuWrench with a simplified structure
US6955104Jul 1, 2002Oct 18, 2005Bobby HuReversible ratcheting tool with a smaller head
US6971286Jul 22, 2003Dec 6, 2005Bobby HuRatcheting wrench with quick tightening/loosening functions and fine adjusting functions
US6971287Jan 19, 2005Dec 6, 2005Easco Hand Tools, Inc.Reversible ratcheting tool with improved control member
US6988429Jan 6, 2004Jan 24, 2006Easco Hand Tools, Inc.Reversible ratcheting tool with improved control member
US7017453Sep 3, 2002Mar 28, 2006Bobby HuReversible ratchet-type wrench
US7032478Jul 6, 2005Apr 25, 2006Bobby HuRatcheting wrench with quick tightening/loosening functions and fine adjusting functions
US7059219Jan 19, 2005Jun 13, 2006Easco Hand Tools, Inc.Reversible ratcheting tool with improved control member
US7178429Dec 12, 2002Feb 20, 2007Yen-Wen LinEasy-to-assemble ratcheting tool
US7234372Aug 15, 2002Jun 26, 2007Bobby HuReversible ratcheting tool with a smaller head and improved driving torque
US7237460Aug 29, 2001Jul 3, 2007Bobby HuBiasing arrangement for a pawl of a reversible ratchet-type wrench
US7353735Jun 2, 2005Apr 8, 2008The Stanley WorksRatchet wrench
US8042433 *Jun 29, 2009Oct 25, 2011Jiutsang LimitedReplacement structure of ratchet wrench
US8596168 *Nov 24, 2012Dec 3, 2013Chi Sung RowOpen end ratcheting wrench
USRE43286Nov 21, 2002Apr 3, 2012Bobby HuRatchet wheel with asymmetric arcuate concave teeth or non-arcuate concave teeth ratcheting tools with such ratchet wheel and combination of such ratchet wheel and a pawl
EP1484136A2 *Dec 8, 2000Dec 8, 2004Bobby HuReversible ratcheting tool with a small head
U.S. Classification192/43.1, 81/63, 81/63.1
International ClassificationB25B13/46, B25B13/00
Cooperative ClassificationB25B13/463
European ClassificationB25B13/46B1B