US3131451A - Safety belt buckle - Google Patents

Safety belt buckle Download PDF

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Publication number
US3131451A
US3131451A US207262A US20726262A US3131451A US 3131451 A US3131451 A US 3131451A US 207262 A US207262 A US 207262A US 20726262 A US20726262 A US 20726262A US 3131451 A US3131451 A US 3131451A
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United States
Prior art keywords
latch
tongue
base
latch plate
buckle
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
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US207262A
Inventor
Robert C Fisher
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HAMILL Manufacturing CO
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HAMILL Manufacturing CO
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Publication date
Application filed by HAMILL Manufacturing CO filed Critical HAMILL Manufacturing CO
Priority to US207262A priority Critical patent/US3131451A/en
Priority to SE7302/63A priority patent/SE301915B/xx
Priority to DEF40128A priority patent/DE1246295B/en
Priority to GB26137/63A priority patent/GB1039723A/en
Priority to FR940273A priority patent/FR1366289A/en
Priority to US366673A priority patent/US3274655A/en
Application granted granted Critical
Publication of US3131451A publication Critical patent/US3131451A/en
Priority to US26754D priority patent/USRE26754E/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • AHUMAN NECESSITIES
    • A44HABERDASHERY; JEWELLERY
    • A44BBUTTONS, PINS, BUCKLES, SLIDE FASTENERS, OR THE LIKE
    • A44B11/00Buckles; Similar fasteners for interconnecting straps or the like, e.g. for safety belts
    • A44B11/25Buckles; Similar fasteners for interconnecting straps or the like, e.g. for safety belts with two or more separable parts
    • A44B11/2503Safety buckles
    • A44B11/2526Safety buckles with an operating lever
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T24/00Buckles, buttons, clasps, etc.
    • Y10T24/45Separable-fastener or required component thereof [e.g., projection and cavity to complete interlock]
    • Y10T24/45225Separable-fastener or required component thereof [e.g., projection and cavity to complete interlock] including member having distinct formations and mating member selectively interlocking therewith
    • Y10T24/45602Receiving member includes either movable connection between interlocking components or variable configuration cavity
    • Y10T24/45623Receiving member includes either movable connection between interlocking components or variable configuration cavity and operator therefor
    • Y10T24/45639Receiving member includes either movable connection between interlocking components or variable configuration cavity and operator therefor including pivotally connected element on receiving member
    • Y10T24/45644Receiving member includes either movable connection between interlocking components or variable configuration cavity and operator therefor including pivotally connected element on receiving member for shifting pivotally connected interlocking component

Definitions

  • the safety belt buckle of the instant invention presents a material step forward in the safety belt buckle art since its design considers the many environmental and aesthetic factors which are necessarily a part of a totally satisfactory belt buckle.
  • the safety belt buckle of the instant invention sets a new standard in terms of strength.
  • the various optimum qualities of a safety belt buckle have been ingeniously integrated into a safety belt buckle that is relatively light in weight, relatively small in physical dimension, easy to open and close, and clean and smooth in appearance.
  • a safety belt buckle it is desirable for a safety belt buckle to be relatively lightweight.
  • One way to reduce the weight of such a buckle assembly is to reduce the gauge of the metal employed in the components of the buckle.
  • any reduction in gauge necessitates careful stress analysis of the components of the belt buckle.
  • the gauge of the metallic components of the buckle can be minimized by substantially eliminating any couples acting on the components of the buckle.
  • one object of the instant invention is a safety belt buckle wherein loads are transmitted to and through the buckle without producing any substantial couples on the components of the buckle.
  • Safety belt buckles heretofore known and used have often employed relatively long, heavy, and therefore cumbersome release handles. This has been a requirement in such known buckles in order to obtain sufficient mechanical advantage to effect opening of the buckle under load.
  • another object of the instant invention is a safety belt buckle having a relatively short, light and therefore easily assembled and operated release handle.
  • a safety belt buckle having a minimum number of com ponents.
  • stamped parts can be produced in large quantities at relatively low cost, as opposed to, for example, die casting or machined parts. Because the 3,131,451 Patented May 5, 1964 cost of the finished safety belt buckle is directly related to the cost of its components, it is an object of the instant invention to reduce the cost of the buckle by making the buckle entirely of stampings.
  • yet another object of the instant invention is a safety belt buckle wherein load tends to tighten the latch, thereby obviating the need for a spring or other form of latch retainer when the belt buckle is under load.
  • Another desirable feature that speeds and reduces the cost of assembly of a safety belt buckle is that the components thereof are self-retained, thereby eliminating fastening pins, screws or the like.
  • Yet another object of the instant invention is a safety belt buckle comprised of components that are self-contained, rendering assembly a relatively simple and quick procedure.
  • a flanged channel has a relatively large strength to weight and size ratio. Accordingly, another object of the instant invention is to utilize a flanged channel as the load-accepting member of a safety belt buckle.
  • a safety belt buckle it is desirable for a safety belt buckle to be openable by only one hand, or, in other words, a pull on the release handle should effect separation of the buckle and tongue.
  • another object of the instant invention is a belt buckle wherein operation of the release handle is in the proper direction to allow one-hand release.
  • the release handle of a seat belt buckle be movable in what may be termed a lever action as opposed to, for example, a scissors or camming action.
  • a lever action increases the mechanical advantage of the release handle so that release force is a minimum under load.
  • Such an action also increases the amount of movement necessary to effect unlatching, thereby minimizing the possibility of accidental unlatching, and permits the use of a short, relatively light release handle, minimizing the chance of accidental unlatehing by a coat sleeve, etc.
  • yet another object of the instant invention is a safety seat belt buckle having a release handle that operates with a lever action.
  • Another object of the instant invention is a safety belt buckle wherein the release handle does not open upon insertion of the tongue into the buckle, allowing the buckle to be held in one hand while being assembled.
  • Yet another object is a safety belt buckle having a relatively clean and low profile.
  • Safety belts must withstand relatively high inertia or G forces attendant to a head-on collision or collision lengthening of the belt.
  • yet another object of the instant invention is a safety belt buckle wherein inertia or G forces tend to tighten the latch, as opposed to opening the latch.
  • Safety belt buckles are subject to jostling in a motorists lap or to minor impacts with hands, articles carried on'the automobile seat, etc.
  • another object of the instant invention is a belt buckle wherein the adjusting mechanism cannot be spuriously released to permit loosening of the belt.
  • yet another object of the instant invention is a safety belt buckle that permits shortening of the safety belt without requiring release of the adjusting mechanism.
  • Another object of the instant invention is an adjusting mechanism for a safety belt buckle having an improved tension bar of relatively 110w profile, thereby to minimize the overall height of the buckle.
  • still another object of the instant invention is a buckle for a safety belt that is relatively clean and .smooth. and has. no parts projecting through the sides thereof so, as to minimizethe possibility of catching and along the line 33 of FIG. 2;
  • FIG. 4 is an exploded perspective view of the safety belt buckle of FIGURE 1;
  • ' 5 is a cross sectional view taken substantially along the line 55 of FIGURE 1;
  • FIG. 6 is across sectional view similar to FIG. 5 with the tongue engaged within the buckle;
  • FIG. 7 is a view similar to FIG 5 with the release handle and latch plate rotated to the release condition
  • FIG. 8 is a fragmentary view ofthe adjustment slide showing the belt bar rotated to facilitate shortening of Q the belt.
  • a safety belt buckle 10 in accordance with an exemplary embodiment of the instant invention, comprises a base 12, a latch plate 1 a latchspringll, ahandle 18, a belt bar 2% and a rear slide 22'
  • the foregoing components are assembled in interlocking relationship on the'base 12 and areself-retained in the assembled condition, as will be described.
  • a tongue 39 (FIGURE 1) is adapted to be releasably accepted and retained withinthe buckleltl.
  • An end portion 34 of a V the base 12 by the retainer portion 50 thereof.
  • the base 12 of the buckle 1% is of channel-like lateral cross sectional configuration defined by a web portion 40 with flange portions 42 and 44 at the opposite edges thereof.
  • Theflange portions 42 and 44 of the base 12 have inwardly folded edges 46 and 48 thereon, respectively, that extend generally parallel to the web portion 40 thereof.
  • the web portion 46 of the base 12 has a reentrantly folded latch retainer 56 at one end. thereof that pivotally accepts an edge portion 52 of the latch plate 14.
  • the latch plate 14 is both supported for rotationrelative to the base 12 and retained against movement outwardly of
  • a pair of tongue strippers 60 and 62 are. struck up- I wardly from the web portion 40.0f the base 12 and are receivable in a pair of complementary cutouts 64 and 66 in the latch plate 14, respectively.
  • the tonguestrippers tit) and 62 serve to position the tongue 30 against the undersidev of the edge portions 45 and 48 to retain the tongue 30 in this position upon retraction of the latch plate 14,
  • the base 12 is provided'with a second pair of cars 70 and 72 that are struck upwardly from the web portion 40 thereof for the retention of the rear slide22 and to position the handle 18 and latch plate 14.
  • a frontal lip 74 of the rea'rslide 22 is engageable over the ears 70 and 72 upon assembly, as will be described.
  • the base portion 12 is provided with'a laterally extending slot 81) for the acceptance of the end portion 34 of the belt 36, which is looped about the bar 20.
  • the latch plate 14 has a latch face on an offset portion 91 that is struck outwardly from the surface'of-the latch plate 14.
  • the latch face 90 is engageable with a complementary latch surface 92 on the periphery ofan aperture 93 in the tongue 30 to eifect locking of the tongue 3% within the buckle 10.
  • the latch plate .14 is normally biased toward the latched condition by the leaf spring 16, one end portion .ltltl'of which is disposed about the ofiset portion 91 of the latch plate Y14 and the other ,end portion 102- of which engages the web portion 40 of the base 12.
  • the olfset portionlllt) of the handle 18 has a pair of ears lll2and 114 that are accepted in complementary cutoutszll5hand 50 116 onthe latch plate 14, thereby to retain the handle 18 in the position shown inthe drawings.
  • the belt bar 249 is supported by a pair of inwardly extending ears 126 downwardlyf depending rear portion 124 of the rear slide '22.
  • the barZtt is retained in a pair of truncated triangular apertures-130 and 132 inthe ears 1% and 122, respectively.
  • the bar- '20 is of generally tear-shaped cross section with coined or flattened end portions 134 and 136 that are accepted in the apertures 330 and .132, respectively.
  • the bar 20 is supported by the apertures 130 and 132 in spaced relation to the web portion of the base 12 an amount approximately equal to the thickness of the belt 36 so that, upon the application of load to the belt 36, the bar 20 and the portion 142 of the base 12 move into mutually reinforcing relation and also effect a slight pinch of the belt 36 therebetween.
  • a rib 144- is displaced upwardly from the web portion 40 of the base 12 to aid the lip 74 in limiting movement of the slide 22 relative to the base 12 under load.
  • the rib 144 also precludes slip of the belt 36 when the buckle 10 is subjected to severe loads.
  • the seat belt buckle 10 of the instant invention is assembled by first engaging the end portion 100 of the latch spring 1 6 about the offset portion 91 of the latch plate 14, as seen in FIG. 5.
  • the assembled latch plate 14 and spring 16 are then inserted under the edge portions 46 and 48 of the base 12, and moved inwardly of the base 12 to the position shown in FIG. 8 of the drawings.
  • the offset portion 11! and ears 112 and 114 of the release handle 18 are then inserted under the edge portions 46 and 48 of the base 12, the ears 112 and 114 sliding over the latch plate 14 until they are received within the cutout portions 115 and 116 thereof, respectively.
  • the handle is retained from outward movement from the base 12.
  • the bar 20 is next assembled with the slide 22 by inserting the edge portion 134 thereof into the aperture 130 in the car 120 of the slide 22, thence snapping the opposite edge portion 136 of the bar 20 into its complementary aperture 132.
  • the end portion 34 of the belt 36 is inserted through the slot 80' in the base 12, thence about the bar 24
  • the assembled bar 29, slide 22 and end portion 34 of the belt 36 are then inserted into the open end of the base 12 from the left, as seen in the drawings, the ears 120 and 122 being accepted between the edge portions 46 and 48 and the web portion '40 of the base 12.
  • the assembled slide 22 and bar 20 are moved inwardly of the base 12 until the lip portion '74 of the slide 22 snaps over the upstanding ears '70 and 72.
  • the dimensional relationship of the lip portion 74 and the height of the ears 7t) and 72 are such that resilience of the slide 22 accommodates the aforementioned snapping of the lip portion 74 over the ears 7% and 72.
  • the release handle 18 of the buckle 10 is of relatively light gauge material and relatively short in length. Thus, it is not cumbersome and is relatively easily operated.
  • the belt buckle 10 of the instant invention comprises only seven components, including the tongue 36, each of which is made by a stamping or coining process.
  • the latch plate 14 is biased toward a latching condition relative to the latch surface 92 of the tongue 30 upon the application of load to the buckle 10.
  • the latch plate 14, handle 18, bar 20 and slide 22 are retained on the base portion 12 of the buckle 111 by mutually interlocking engagement.
  • the use of retaining pins, screws, or other elements having the single function of retaining the components of the buckle 10* in an assembled condition are eliminated.
  • the base member 12 forms the basic load-carrying and supporting component of the buckle 1t and that the base 12 comprises a flanged channel of relatively large strength-to-weight ratio.
  • the properties of the flange channel are utilized to maximize the strength of the buckle 11), while minimizing the size and weight thereof.
  • the release handle 18 of the buckle 10 is movable counterclockwise or in a direction opposite to the direction of movement of the tongue 31] upon movement of the release handle 18 to the release condition.
  • an occupant of the motor vehicle is merely required to pull on the handle 18 a to effect separation of the tongue 3% from the base portion 117 of the release handle 18 is at a distance which is relatively close to the pivot point of the offset portion 111? on the underside of the edges 4-6 and 48 of the base portion 12 relative to the total length of the handle 13.
  • the handle 18 operates as a lever having a rela tively large mechanical advantage so that the end portion 118 of the latch plate 14 can be biased downwardly against the frictional force acting between the latch face and the latch surface 92 so that the tongue 31 can be freed from the base portion 12 by a relatively light force, even though the buckle 111 is subjected to a substantial load.
  • insertion of the tongue 31) into the base portion 12 of the buckle does not require movement of the release handle 18.
  • the tongue 3% moves into the base 12, it is guided by the edge portions 46 and 48 of the base 12 and the strippers 6t) and 62 so as to bias the latch plate 14 downwardly, allowing the latch face 91) thereon to clear the tongue 30, thence move upwardly into the latching condition with the latch surface 92 on the tongue 30 under the bias of the operating spring 16 when the tongue 30 is fully inserted into the base portion 12.
  • the safety belt buckle 16 can be easily grasped in one hand, facilitating insertion of the tongue 30 with the other hand.
  • the frontal edge portion of the handle 18 is reentrantly folded to form a guide that directs the tongue 31) into the proper aligned position under the edge portions 46 and 48 of the base 12.
  • the reentrantly folded latch retainer 50 on the web 40 of the base 12 tends to guide the tongue 30 into proper alignment for insertion.
  • the foregoing reentrantly folded surfaces thus form an obvious opening in the buckle 10 for the acceptance of the tongue 30. Further, should the tongue 31 be inserted under the release handle 18, but on top of the edges 46 and 48 of the base 12, spurious latching is precluded, since the latch face 90 on the latch plate 14 cannot effect latching with the surface 92 on the tongue 30.
  • G forces operative on the latch plate of a buckle do not tend to spuriously open the buckle and effect release of the tongue thereof.
  • the tongue 30 is disposed over the latch plate 14.
  • G forces having an upward vector operable on the latch plate 14 due to, for example, impact of an automobile with an object tend to move the latch plate 14 upwardly, thus tending to retain the latch plate 14- and latch face 94) thereof in engagement with the complementary latch surface 92 on the tongue 30.
  • lengthening of the belt 36 requires both movement of the slide 22 inwardly of the base 12 and tilting of the buckle 19 relative to the end portion 34 of the belt 36.
  • the belt buckle it is so tilted and the slide 22 is moved inwardly as by a longitudinal squeeze, lengthening of the belt 36 can be effected with one hand by merely pulling on the buckle It).
  • the slide 22 is moved to the release position.
  • Shortening of the belt 36 is effected by merely pulling on the top or free end portion 34 of the belt 36, which action tends to rotate the locking bar 20 upwardly to the position shown in FIG. 8, so that the upper surfaces of Y the flattened end portions 134 and 136 engage the upper edge portions of the apertures 130 and 132 in the slide ears 126 and 122, respectively.
  • the angular relationship of the belt bar 20 is such that the belt moves freely over the bar 2 to permit shortening of the belt 36. It is to be noted that the shortening operation does not require movement of the slide 22 to the release condition required to effect lengthening of the belt 36.
  • This mode of operation again reflects an awareness of the actual condition that obtains in a motor vehicle, since it is normal for an occupant to assemble the tongue 3% with the belt buckle it) or .base portion 12 of the buckle Ill, thence effect shortening of the belt to a desired length comfortable to the motorist. Shortening of the belt 36 can thus be effected by only one handworking against the oppositeend of the belt.
  • the bar 20 is substantially free of knurled, abraded or otherwise roughened surfaces, whichtend to accelerate wear of the belt 36.
  • the belt buckle of. the instant invention is relatively clean and entirely free of protruding surfaces or components.
  • the buckle ltl does not tend to catch clothing or otherwise present sharp surfaces that might limit use of the buckle
  • the safety belt buckle'lii of the instant invention can l the belt bar relative to the width of the slotfili in the web portion 4t? of the base 12 precludesspurious release of the end portion 34 of the belt 36 due to accidental tipping of the buckle It).
  • the belt bar 20 is of substantially flat crosssectional configuration,- thereby to allow a relatively low and plean profile for the buckle it which adds to its aestheticappeal, aswell as minimizing the overall size andweight thereof; 7
  • a safety belt-buckle comprising a base member having a web portion with upstanding flanges on opposite sides with inturned edge portions extending in spaced generally parallel relationship to the web portion thereof, said base member having a latch plate retainer at one end thereof, a latch plate overlying the web portion of said base member in generally parallel relationship and having -one-end pivoted in the latch retainer of said base,
  • said latch plate having a latch face thereon, a belt tongue having a latch surface thereon and being insertable under the edge portions of said base member in overlying generally parallel relation to said latch plate, the latch face on said latch plate being engageable with the latch surface on said tongue to lock said tongue against movement outwardly of said .base, resilient means normally biasing said. latch .plate toward said tongue, and a release handle having apair.
  • a safety belt buckle comprising a base member having a web portion with upstanding flanges on opposite sides with inturned edge portions extending in spaced generally parallel relationship to the web portion thereof, said base memberhaving a latch plate retainer at one end thereof and a pair of tongue strippers extendinginto closely spaced relation to the edge portions thereof, respectively, a latch plate overlying the web portion of said 'basemember in generally parallel relationship and having one end pivoted in the latch retainer of said base and a pair of apertures for the acceptance of the tongue-strippers on said 9 base, respectively, said latch plate having a laterally offset latch face on the opposite side thereof from the web portion of said base, a belt tongue having an aperture defining a latch surface, said belt tongue being insertable under the edge portions of said base member in overlying generally parallel relation to said latch plate, the latch face on said latch plate being engageable with the latch surface on said tongue to lock said tongue against movement outwardly of said base, resilient means between the web portion of said base and said latch plate for normally biasing said latch
  • a release handle having an intermediate portion pivotally engaged with the edge portions of said base member adjacent the other end of said latch plate and overlying said tongue, one end portion of said handle engaging the other end of said latch plate whereby movement of the other end portion of said release handle in one direction relative to said base effects disengagement of the latch face on said latch plate from the latch surface on said tongue and conditions said tongue for movement in the opposite direction relative to said base.
  • a safety belt buckle comprising a sheet metal base member having a web portion with upwardly folded flanges on opposite sides with inwardly folded edge portions extending in spaced generally parallel relationship to the web portion thereof, said base member having a latch plate retainer reentrantly folded at one end thereof, a sheet metal latch plate overlying the web portion of said base member in generally parallel relationship and having one end pivoted in the latch retainer of said base,
  • said latch plate having a laterally extending latch face thereon, a sheet metal belt tongue having a laterally extending latch surface thereon, said tongue being insertable under the edge portions of said base member in overlying generally parallel relation to said latch plate, the latch face on said latch plate being engageable with the latch surface on said tongue to lock said tongue against movement outwardly of said base, a leaf spring disposed between the web portion of said base and said latch plate and normally biasing said latch plate toward said tongue, and
  • a sheet metal release handle having a pair of ears on opposite sides thereof engaged under the edge portions of said base whereby said handle is pivotally supported by said base member adjacent the other end of said latch plate, said handle overlying said tongue, said handle engaging the other end of said latch plate so that rotation of said release handle relative to said base effects rotation of said latch plate and disengagement of the latch face on said latch plate from the latch surface on said tongue.
  • a safety belt buckle comprising a base member having a web portion with upstanding flanges on opposite sides with inturned edge portions extending in spaced generally parallel relationship to the web portion thereof, said base member havin a latch plate retainer I at one end thereof, a latch plate overlying the Web portion of said base member in generally parallel relationship and having one end pivoted in the latch retainer of said base,
  • said latch plate having a laterally ofiset latch face on the opposite side thereof from the web portion of said base, a belt tongue having an aperture defining a latch surface, said belt tongue being insertable under the edge portions of said base member in overlying generally parallel relation to said latch plate, the latch face on said latch plate being engageable with the latch surface on said tongue to lock said tongue against movement outwardly of said base, resilient means between the web portion of said base and said latch plate for normally biasing said latch plate toward said tongue, and a release handle extending generally parallel to said belt tongue and having an intermediate portion pivotally engaged under and interlocked with the edge portions of said base member adjacent the other end of said latch plate, one end portion of said handle relatively close to the intermediate portion thereof engaging the other end of said latch plate and the other end portion of said release handle being spaced relatively farther from the pivoted intermediate portion so as to provide a mechanical advantage to facilitate movement of the latch face on said latch plate laterally of said tongue upon rotation of said handle.
  • a safety belt buckle comprising a base member having a web portion with upstanding flanges on opposite sides thereof with inturned edge portions extending in spaced generally parallel relationship to the web portion there of, said base member having means at one end thereof for retaining a latch plate and means atanother end for retaining a release handle,
  • a latch plate having a'latch -thereon,-.said latch plate being disposed between the Web portion and edge portions of said base, resilient means between the web portion of said base and said latch plate for normally biasing said latch plate away from-the-web portion of said base, a release handle having a pair of oppositely laterally extending ears engaged under and retained by the edge portions of said base member whereby saidrelease handle is pivotally supported-bythe edge portions of said base memher, said handle being engageable with said latch plate to effectmovement thereof against the bias of said spring, and a belt tongue having a latch surface engageable with the latch on said latch plate, said belt tongue being insertable between said latch plate and handle, insertion of said tongue effecting a movement of said latch plate towards the web portion of said base against the bias of said spring whereby said belt tongue can be assembled with said base member without elfecting movement of said handle.
  • a safety belt buckle for a motor vehicle comprising abase member having a web portion with upstanding flanges on opposits sides thereof, said flanges having inturned edge portions extending in spaced generally parallel relationship to the web portion of said base for pivotally supporting a release handle, said base member having a latch plate retainer ---at one end thereof, a latch plate overlying the web portion of said base member in generally parallel relationship, said latch plate having one end pivoted in the latch retainer of said base and having a laterally extending latch face thereon,
  • a belt tongue having alaterally extending latch surface thereon and insertable under the supporting means on said base member in overlying generally parallel relation to said latch plate, the latch face on said latchplate being engageable with the latch surface on said tongue to lock said tongue against movement outwardly of said base, a leaf spring disposed between the webportion of said base and said latch ,plateand normally biasing said latch plate toward said tongue, and
  • a safetybelt-buckle comprising a base member having a. web portion with upstanding flanges 3 on opposite sides thereof with inturned edge portions -extending in spaced generally parallel relationship to the web portion thereof,
  • said basemember having means atone end'thereoffor retaining a latch plateagainst movement in one direction and means at an intermediate portion thereof :iorretaining-said latch plate and a re lease handle against movement in the opposite direction,
  • a latch plate having a latch 3 thereon, said latchplate overlying the 'WCb'POI'tlOH of saidbase member and having means for restraining the release handle against movement in said one direction, albeit tongue having a latch surface engageable with the latch on said latch plate, resilient means between the web portion of said base and said latch plate for normally biasing said latch plate toward said, tongue, and a release handle pivotally supportedby said base member at the intermediate portion thereof, said handle being engageable with said latch plate to effect disengagementof the latch thereon from the latch sur face on said tongue, the edge portions of said base retaining said release handle, tongue, latch plate and resilient means against movement in a direction normal to said one direction whereby said base, latch plate, resilient means and release handle of said buckle are mutually interlocked in an assembled condition.
  • a safety belt buckle comprising a base member having means at. one end thereof for retaining a latch plate against movement in one direction, said base member having means ,for limiting movement of a belt tongue l in a direction normal to said one direction, said basemember having means at;an;intermediatepprtion for retaining a release handle and the latch plate against movement in the Opposite direc- ,tion, a latch plate engaged with the one end portion of said base and means forrestraining a release handle against movement in said one direction,
  • a release handle pivotally supported by said base member at the intermediate portion thereof, said handle being engageable with said latch plate to effect disengagement thereof from said tongue, means for separating said latch plate and belt tongue upon movement of said latch plate in a direction opposite to said normal direction, and
  • a safety belt buckle comprising a base member having a web portion with upstanding flanges on opposite sides, said flanges having inturned edge portions extending in spaced generally parallel relationship to the web portion thereof, said base member having a latch member retainer adjacent one end thereof, a latch member overlying the web portion of said base member in generally parallel relationship and having one end pivoted in the latch retainer of said base, said latch member having a latch face thereon, a belt tongue having a latch surface thereon, said belt tongue being insertable in said base member between said flanges and in generally parallel relation to said latch member, the latch face on said latch member being engageable with the latch surface on said tongue to lock said tongue against movement endwise outwardly of said base, resilient means normally biasing said latch member toward said tongue, means including said inturned edge portions for limiting movement of said latch and tongue away from said web, and a release handle having a pair of oppositely laterally extending projections at one end thereof underlying the edge portions of said base member so as to fulcrum on the underside
  • a safety belt buckle comprising a sheet metal base member having a web portion with upwardly folded flanges on opposite sides, said flanges having inwardly folded edge portions extending in spaced generally parallel relationship to the web portion thereof, said base member having a latch plate retainer reentrantly folded at one end thereof, a sheet metal latch plate overlying the web portion of said base member in generally parallel relationship and having one end fulcrumed in the latch retainer of said base, said latch plate having a laterally extending latch face thereon, a sheet metal belt tongue having a laterally extending latch surface thereon, said tongue being insertable endwise under the edge portions of said base member and on the opposite side of said latch plate from said base, the latch face on said latch plate being engageable with the latch surface on said tongue to lock said tongue against movement endwise outwardly of said base, a sheet metal spring having at least a portion thereof disposed between the web portion of said base and said latch plate and normally biasing said latch plate toward said tongue, and a sheet metal release handle having a pair of
  • a safety belt buckle comprising a base member having a web portion with upstanding flanges on opposite sides, said flanges having inturned edge portions extending in spaced generally parallel relationship to the web portion thereof, said base member having a latch member retainer adjacent one end thereof, a latch member overlying the web portion of said base member in generally parallel relationship and having one end pivoted in the latch retainer of said base, said latch member having a latch face thereon, a belt tongue having a latch surface thereon, said belt tongue being insertable in said base member between said flanges and in generally parallel relation to said latch member, the latch face on said latch member being engageable with the latch surface on said tongue to lock said tongue against movement endwise outwardly of said base, resilient means normally biasing said latch member toward said tongue, and a release handle having a pair of oppositely laterally extending projections at one end thereof underlying the edge portions of said base member so as to fulcrum on the underside of said edge portions, said handle having a portion operative to disengage the latch face on said
  • a safety belt buckle comprising a base memberv having a web portion with upstanding flanges on opposite longitudinally extending sides thereof, said flanges having inturned edge portions extending in spaced generally parallel relationship to the web portion of said base member, said base member having longitudinally spaced means thereon for retaining a latching means against movement in either direction longitudinally of said base, a latching means including a latch member having a latch face thereon and a spring, means including the edge portions of said base member for restraining move ment of said latching means away from the Web portion of said base member, a belt tongue having a latch surface engageable with the latch face on said latch member, said spring normally biasing said latch member toward said tongue, a release handle having oppositely laterally extending projections thereon extending under the edge portions of said base member so as to be pivotally supported by said base member, said handle being engageable with said latch member to eflect disengagement of the latch face thereon from the latch surface on said tongue, means on said latching means for restraining movement of

Description

May 5, 1964 R. c. FISHER SAFETY BELT BUCKLE;
2 Sheets-Sheet 1 Filed July 3, 1962 INVENTOR 2%2622 6'. fir/"Q27 May 5, 1964. R. c. FISHER SAFETY BELT BUCKLE 2 Sheets-Sheet 2 Filed July 3, 1962 S mum INVENTOR. 77 0267; 6', fffili'jdf United States Patent i 3,131,451 SAFETY BELT BUCKLE Robert C. Fisher, Bloomfield Hills, well assignor to Hamill Manufacturing Co., Washington, Mich, a corporation of Michigan Filed July 3, 1962, Ser. No. 207,262 12 Claims. (Cl. 2423t)) This invention relates generally to buckles, and more particularly to an improved buckle for automobile type safety belts.
Recognition of the part that automobile safety belts play in decreasing passenger injuries due to automobile upset and collision has emphasized the need for an improved safety belt buckle capable of withstanding the relatively severe loads to which the buckles of such safety belts are subjected, yet of aesthetically pleasing and economical construction.
The design of automobile safety belt buckles heretofore known and used has emphasized, primarily, the ability of the belt buckle to withstand the relatively severe loads to which such safety belts are subjected. Relatively little attention has been given to the refinement of such buckles to the point where they are aesthetically pleasing, economically constructed, and free of all unsatisfactory operating characteristics.
The safety belt buckle of the instant invention presents a material step forward in the safety belt buckle art since its design considers the many environmental and aesthetic factors which are necessarily a part of a totally satisfactory belt buckle. In addition, the safety belt buckle of the instant invention sets a new standard in terms of strength. The various optimum qualities of a safety belt buckle have been ingeniously integrated into a safety belt buckle that is relatively light in weight, relatively small in physical dimension, easy to open and close, and clean and smooth in appearance.
More particularly, it is desirable for a safety belt buckle to be relatively lightweight. One way to reduce the weight of such a buckle assembly is to reduce the gauge of the metal employed in the components of the buckle. However, any reduction in gauge necessitates careful stress analysis of the components of the belt buckle. As a result of such an analysis, it has been discovered that the gauge of the metallic components of the buckle can be minimized by substantially eliminating any couples acting on the components of the buckle.
Accordingly, one object of the instant invention is a safety belt buckle wherein loads are transmitted to and through the buckle without producing any substantial couples on the components of the buckle.
Safety belt buckles heretofore known and used have often employed relatively long, heavy, and therefore cumbersome release handles. This has been a requirement in such known buckles in order to obtain sufficient mechanical advantage to effect opening of the buckle under load. Thus, another object of the instant invention is a safety belt buckle having a relatively short, light and therefore easily assembled and operated release handle.
The cost of a safety belt buckle is directly related to the number of components employed therein. Thus, in addition to its own cost, each additional component complicates and therefore adds to the cost of assembly. Therefore, another object of the instant invention is a safety belt buckle having a minimum number of com ponents.
It is well known that stamped parts can be produced in large quantities at relatively low cost, as opposed to, for example, die casting or machined parts. Because the 3,131,451 Patented May 5, 1964 cost of the finished safety belt buckle is directly related to the cost of its components, it is an object of the instant invention to reduce the cost of the buckle by making the buckle entirely of stampings.
One deleterious feature of safety buckles heretofore known and used is that the latch portion of the buckle tends to be biased to an unlatched condition when the buckle is subjected to load, thus requiring springs or other devices to maintain the latch in the closed condition.
Accordingly, yet another object of the instant invention is a safety belt buckle wherein load tends to tighten the latch, thereby obviating the need for a spring or other form of latch retainer when the belt buckle is under load.
Another desirable feature that speeds and reduces the cost of assembly of a safety belt buckle is that the components thereof are self-retained, thereby eliminating fastening pins, screws or the like.
Yet another object of the instant invention is a safety belt buckle comprised of components that are self-contained, rendering assembly a relatively simple and quick procedure.
It is well known that a flanged channel has a relatively large strength to weight and size ratio. Accordingly, another object of the instant invention is to utilize a flanged channel as the load-accepting member of a safety belt buckle.
It often occurs that the occupant of a motor vehiclemust release a safety belt by only one hand. This condition may obtain for example, when one hand of the occupant is pinned or otherwise disabled. Thus, it is desirable for a safety belt buckle to be openable by only one hand, or, in other words, a pull on the release handle should effect separation of the buckle and tongue.
Accordingly, another object of the instant invention is a belt buckle wherein operation of the release handle is in the proper direction to allow one-hand release.
It is desirable that the release handle of a seat belt buckle be movable in what may be termed a lever action as opposed to, for example, a scissors or camming action. Such a lever action increases the mechanical advantage of the release handle so that release force is a minimum under load. Such an action also increases the amount of movement necessary to effect unlatching, thereby minimizing the possibility of accidental unlatching, and permits the use of a short, relatively light release handle, minimizing the chance of accidental unlatehing by a coat sleeve, etc.
Accordingly, yet another object of the instant invention is a safety seat belt buckle having a release handle that operates with a lever action.
It is a natural tendency for an occupant of a motor vehicle to grasp a safety belt buckle in one hand and insert the tongue of the belt thereinto with the other hand. Thus, it is desirable for the release handle of the belt buckle to remain in a closed condition upon insertion of the tongue, allowing the occupant to grasp the buckle portion with only one hand. Thus, another object of the instant invention is a safety belt buckle wherein the release handle does not open upon insertion of the tongue into the buckle, allowing the buckle to be held in one hand while being assembled.
Obviously, it is undesirable for a safety belt buckle to be falsely latched. Thus, another object is a belt buckle that precludes spurious engagement of the tongue therewith.
Yet another object is a safety belt buckle having a relatively clean and low profile.
Safety belts must withstand relatively high inertia or G forces attendant to a head-on collision or collision lengthening of the belt.
3 with a relatively immovable object. Thus, yet another object of the instant invention is a safety belt buckle wherein inertia or G forces tend to tighten the latch, as opposed to opening the latch.
Safety belt buckles are subject to jostling in a motorists lap or to minor impacts with hands, articles carried on'the automobile seat, etc. Thus, it is desirable for the belt buckle to be so designed that such actions or impacts do not effect release of the adjustment mechanism and loosening of the belt.
Accordingly, another object of the instant invention is a belt buckle wherein the adjusting mechanism cannot be spuriously released to permit loosening of the belt.
Consonant with the foregoing object, it is desirable to be 'able to shorten a safety belt without necessitating release of the adjusting mechanism thereof. Accordingly,
" yet another object of the instant invention is a safety belt buckle that permits shortening of the safety belt without requiring release of the adjusting mechanism.
' Experience has shown that premature wear of the webbing of a safety belt is aggravated by the use of knurled,
..grooved or otherwise roughened surfaces within the belt buckle. It is an object of the instant invention to eliminatesuch knurled, grooved or otherwise abraded surfaces, thereby to reduce abrasion of the belt webbing.
The overall height of a safety belt buckle is dictated in part by the profile of the tension bar employed in the adjusting mechanism. Therefore, another object of the instant invention is an adjusting mechanism for a safety belt buckle having an improved tension bar of relatively 110w profile, thereby to minimize the overall height of the buckle.
...Safety belt buckles are obviously of no utility unless the occupant of a motor vehicle uses the safety belt. When such buckles are cumbersome and have protruding com- 'ponents that can possibly catch and tear clothing, the safety belt will .not'be utilized.
Accordingly, still another object of the instant invention is a buckle for a safety belt that is relatively clean and .smooth. and has. no parts projecting through the sides thereof so, as to minimizethe possibility of catching and along the line 33 of FIG. 2;
FIG. 4 is an exploded perspective view of the safety belt buckle of FIGURE 1;
' 5 is a cross sectional view taken substantially along the line 55 of FIGURE 1;
- FIG. 6 is across sectional view similar to FIG. 5 with the tongue engaged within the buckle;
FIG. 7 is a view similar to FIG 5 with the release handle and latch plate rotated to the release condition;
1 FIG. 8 is a fragmentary view ofthe adjustment slide showing the belt bar rotated to facilitate shortening of Q the belt; and
@FIG. 9 is a fragmentary view similar to FIG. 8 showing the adjustment slide and buckle in condition to permit As best seen'in FIG. 4 of the drawings, a safety belt buckle 10, in accordance with an exemplary embodiment of the instant invention, comprises a base 12, a latch plate 1 a latchspringll, ahandle 18, a belt bar 2% and a rear slide 22' The foregoing components are assembled in interlocking relationship on the'base 12 and areself-retained in the assembled condition, as will be described. A tongue 39 (FIGURE 1) is adapted to be releasably accepted and retained withinthe buckleltl. An end portion 34 of a V the base 12 by the retainer portion 50 thereof.
and 122 on the slide 22 that extendinwardly from a i belt 36 is adapted to be adjustably looped around the bar 2% and an end portion 38 of the belt 36 is secured to the tongue 36 as by stitching 39.
As best seen in FIGS. 4 through 8 of the drawings, the base 12 of the buckle 1% is of channel-like lateral cross sectional configuration defined by a web portion 40 with flange portions 42 and 44 at the opposite edges thereof. Theflange portions 42 and 44 of the base 12 have inwardly folded edges 46 and 48 thereon, respectively, that extend generally parallel to the web portion 40 thereof.
The web portion 46 of the base 12 has a reentrantly folded latch retainer 56 at one end. thereof that pivotally accepts an edge portion 52 of the latch plate 14.. The latch plate 14 is both supported for rotationrelative to the base 12 and retained against movement outwardly of A pair of tongue strippers 60 and 62 are. struck up- I wardly from the web portion 40.0f the base 12 and are receivable in a pair of complementary cutouts 64 and 66 in the latch plate 14, respectively. The tonguestrippers tit) and 62 serve to position the tongue 30 against the undersidev of the edge portions 45 and 48 to retain the tongue 30 in this position upon retraction of the latch plate 14,
as will be described.
The base 12 is provided'with a second pair of cars 70 and 72 that are struck upwardly from the web portion 40 thereof for the retention of the rear slide22 and to position the handle 18 and latch plate 14. A frontal lip 74 of the rea'rslide 22 is engageable over the ears 70 and 72 upon assembly, as will be described.
The base portion 12 is provided with'a laterally extending slot 81) for the acceptance of the end portion 34 of the belt 36, which is looped about the bar 20.
The latch plate 14 has a latch face on an offset portion 91 that is struck outwardly from the surface'of-the latch plate 14. The latch face 90 is engageable with a complementary latch surface 92 on the periphery ofan aperture 93 in the tongue 30 to eifect locking of the tongue 3% within the buckle 10.
- The latch plate .14 is normally biased toward the latched condition by the leaf spring 16, one end portion .ltltl'of which is disposed about the ofiset portion 91 of the latch plate Y14 and the other ,end portion 102- of which engages the web portion 40 of the base 12.
substantially close the top of the buckle 10. The olfset portionlllt) of the handle 18. has a pair of ears lll2and 114 that are accepted in complementary cutoutszll5hand 50 116 onthe latch plate 14, thereby to retain the handle 18 in the position shown inthe drawings.
As can best be seen by comparing FIGS. 5, 6. and 7,
portion 117 thereof into engagement with an inner end portion 118 of the latch plateid, thereby to cam the latch :plate 14 about the latch retainer .50 on the base 12 toward the open condition.
As best seen in FIGS. 5 through 9, the belt bar 249 is supported by a pair of inwardly extending ears 126 downwardlyf depending rear portion 124 of the rear slide '22.
As best seenin FIGS. 7, 8 and 9, the barZtt is retained in a pair of truncated triangular apertures-130 and 132 inthe ears 1% and 122, respectively. The bar- '20 is of generally tear-shaped cross section with coined or flattened end portions 134 and 136 that are accepted in the apertures 330 and .132, respectively.
.As best seen. in RIG. 5 of the drawings, the end portion -34 of thebeltfifi is looped over the bar- 2-0 and extends downwardly through the aperture St in the web portion It is to be-noted that, as shown in PEG. 6, when the belt buckle 1d is under load, an edge portionl lti of the bar 29 substantially overlies a-frontal edge portion 142 of the web 40 of the base 12. Also, the bar 20 is supported by the apertures 130 and 132 in spaced relation to the web portion of the base 12 an amount approximately equal to the thickness of the belt 36 so that, upon the application of load to the belt 36, the bar 20 and the portion 142 of the base 12 move into mutually reinforcing relation and also effect a slight pinch of the belt 36 therebetween.
It is also to be noted that a rib 144- is displaced upwardly from the web portion 40 of the base 12 to aid the lip 74 in limiting movement of the slide 22 relative to the base 12 under load. The rib 144 also precludes slip of the belt 36 when the buckle 10 is subjected to severe loads.
The seat belt buckle 10 of the instant invention is assembled by first engaging the end portion 100 of the latch spring 1 6 about the offset portion 91 of the latch plate 14, as seen in FIG. 5. The assembled latch plate 14 and spring 16 are then inserted under the edge portions 46 and 48 of the base 12, and moved inwardly of the base 12 to the position shown in FIG. 8 of the drawings. The offset portion 11! and ears 112 and 114 of the release handle 18 are then inserted under the edge portions 46 and 48 of the base 12, the ears 112 and 114 sliding over the latch plate 14 until they are received within the cutout portions 115 and 116 thereof, respectively. When the ear portions 112 and 114 drop into the cutouts 115 and 116, respectively, the handle is retained from outward movement from the base 12.
The bar 20 is next assembled with the slide 22 by inserting the edge portion 134 thereof into the aperture 130 in the car 120 of the slide 22, thence snapping the opposite edge portion 136 of the bar 20 into its complementary aperture 132. The end portion 34 of the belt 36 is inserted through the slot 80' in the base 12, thence about the bar 24 The assembled bar 29, slide 22 and end portion 34 of the belt 36 are then inserted into the open end of the base 12 from the left, as seen in the drawings, the ears 120 and 122 being accepted between the edge portions 46 and 48 and the web portion '40 of the base 12. The assembled slide 22 and bar 20 are moved inwardly of the base 12 until the lip portion '74 of the slide 22 snaps over the upstanding ears '70 and 72. The dimensional relationship of the lip portion 74 and the height of the ears 7t) and 72 are such that resilience of the slide 22 accommodates the aforementioned snapping of the lip portion 74 over the ears 7% and 72. After the slide 22is moved to the assembled condition, as shown in FIG. 5 of the drawings, the edge or lip portion '74 precludes disassembly of the slide 22 on the base 12.
It is to be noted that couples acting on the safety belt buckle 11 are minimized, since load is transmitted to the tongue 30 from the end portion 38 of the belt 36, thence from the latch surface '92 on the aperture 23 in the tongue 30 to the latch face 91 on the latch plate 14. The load is then transmitted substantially in a straight line generally parallel to the tongue 30' to the edge portion 52 of the latch plate 14, thence to the reentrantly folded edge portion St) on the web 40 of the base 12. Load is then transmitted through the web 40 of the base 12 and flange portions 42 and 44 of the base 12 to the opposite end portion 142 thereof, thence to the end portion 34 of the belt 36.
It is to be noted that the release handle 18 of the buckle 10 is of relatively light gauge material and relatively short in length. Thus, it is not cumbersome and is relatively easily operated.
As best seen in FIG. 4 of the drawings, the belt buckle 10 of the instant invention comprises only seven components, including the tongue 36, each of which is made by a stamping or coining process.
In accordance with yet another feature of the instant invention, the latch plate 14 is biased toward a latching condition relative to the latch surface 92 of the tongue 30 upon the application of load to the buckle 10. The
relatively small moment acting on the latch plate 14 tends to rotate the latch plate clockwise, as seen in FIG. 6 of the drawings, thereby relieving the operating spring 1 6 of its function of holding the latch plate 14 in the engaged condition with the tongue 30 when the buckle 10 is subjected to load.
As discussed hereinbefore, the latch plate 14, handle 18, bar 20 and slide 22 are retained on the base portion 12 of the buckle 111 by mutually interlocking engagement. Thus, the use of retaining pins, screws, or other elements having the single function of retaining the components of the buckle 10* in an assembled condition are eliminated.
From the foregoing description, it should be apparent that the base member 12 forms the basic load-carrying and supporting component of the buckle 1t and that the base 12 comprises a flanged channel of relatively large strength-to-weight ratio. Thus, the properties of the flange channel are utilized to maximize the strength of the buckle 11), while minimizing the size and weight thereof.
As best seen in FIG. 7 of the drawings, the release handle 18 of the buckle 10 is movable counterclockwise or in a direction opposite to the direction of movement of the tongue 31] upon movement of the release handle 18 to the release condition. Thus, an occupant of the motor vehicle is merely required to pull on the handle 18 a to effect separation of the tongue 3% from the base portion 117 of the release handle 18 is at a distance which is relatively close to the pivot point of the offset portion 111? on the underside of the edges 4-6 and 48 of the base portion 12 relative to the total length of the handle 13. Thus, the handle 18 operates as a lever having a rela tively large mechanical advantage so that the end portion 118 of the latch plate 14 can be biased downwardly against the frictional force acting between the latch face and the latch surface 92 so that the tongue 31 can be freed from the base portion 12 by a relatively light force, even though the buckle 111 is subjected to a substantial load.
As can be seen by comparing FIGS. 5 and 6, insertion of the tongue 31) into the base portion 12 of the buckle does not require movement of the release handle 18. As the tongue 3% moves into the base 12, it is guided by the edge portions 46 and 48 of the base 12 and the strippers 6t) and 62 so as to bias the latch plate 14 downwardly, allowing the latch face 91) thereon to clear the tongue 30, thence move upwardly into the latching condition with the latch surface 92 on the tongue 30 under the bias of the operating spring 16 when the tongue 30 is fully inserted into the base portion 12. Thus, the safety belt buckle 16 can be easily grasped in one hand, facilitating insertion of the tongue 30 with the other hand.
It is to be noted that the frontal edge portion of the handle 18 is reentrantly folded to form a guide that directs the tongue 31) into the proper aligned position under the edge portions 46 and 48 of the base 12. Also, the reentrantly folded latch retainer 50 on the web 40 of the base 12 tends to guide the tongue 30 into proper alignment for insertion. The foregoing reentrantly folded surfaces thus form an obvious opening in the buckle 10 for the acceptance of the tongue 30. Further, should the tongue 31 be inserted under the release handle 18, but on top of the edges 46 and 48 of the base 12, spurious latching is precluded, since the latch face 90 on the latch plate 14 cannot effect latching with the surface 92 on the tongue 30.
As discussed hereinbefore, it is desirable that high inertia or G forces operative on the latch plate of a buckle do not tend to spuriously open the buckle and effect release of the tongue thereof. As can be seen by inspection of, for example, FIG. 6, the tongue 30 is disposed over the latch plate 14. Thus, G forces having an upward vector operable on the latch plate 14 due to, for example, impact of an automobile with an object, tend to move the latch plate 14 upwardly, thus tending to retain the latch plate 14- and latch face 94) thereof in engagement with the complementary latch surface 92 on the tongue 30.
As can be seen by inspecting FIG. 9 of the drawings, lengthening of the belt 36 requires both movement of the slide 22 inwardly of the base 12 and tilting of the buckle 19 relative to the end portion 34 of the belt 36. When the belt buckle it) is so tilted and the slide 22 is moved inwardly as by a longitudinal squeeze, lengthening of the belt 36 can be effected with one hand by merely pulling on the buckle It). It is also to be noted that by gripping the buckle It) at opposite ends thereof in order to lengthen the belt 36, the slide 22 is moved to the release position.
Shortening of the belt 36 is effected by merely pulling on the top or free end portion 34 of the belt 36, which action tends to rotate the locking bar 20 upwardly to the position shown in FIG. 8, so that the upper surfaces of Y the flattened end portions 134 and 136 engage the upper edge portions of the apertures 130 and 132 in the slide ears 126 and 122, respectively. When in this position, the angular relationship of the belt bar 20 is such that the belt moves freely over the bar 2 to permit shortening of the belt 36. It is to be noted that the shortening operation does not require movement of the slide 22 to the release condition required to effect lengthening of the belt 36. This mode of operation again reflects an awareness of the actual condition that obtains in a motor vehicle, since it is normal for an occupant to assemble the tongue 3% with the belt buckle it) or .base portion 12 of the buckle Ill, thence effect shortening of the belt to a desired length comfortable to the motorist. Shortening of the belt 36 can thus be effected by only one handworking against the oppositeend of the belt.
The bar 20 is substantially free of knurled, abraded or otherwise roughened surfaces, whichtend to accelerate wear of the belt 36. The novel configuration and orientation of the bar 29, in combination with its disposition in spaced relation to the web portion 49 of the base .12 and overlying the portion 142 of the base 12, all are mutually complementary. to facilitate holding of the belt .36 .under load without requiring such knurled or roughened surfaces.
As can bestbe seen from FIGS. 1, 2 and 3, the belt buckle of. the instant invention is relatively clean and entirely free of protruding surfaces or components. Thus, the buckle ltl does not tend to catch clothing or otherwise present sharp surfaces that might limit use of the buckle From the foregoing description, it should be apparent that the safety belt buckle'lii of the instant invention can l the belt bar relative to the width of the slotfili in the web portion 4t? of the base 12 precludesspurious release of the end portion 34 of the belt 36 due to accidental tipping of the buckle It).
Yet another feature of the buckle .10 of the instant invention is that the belt bar 20 is of substantially flat crosssectional configuration,- thereby to allow a relatively low and plean profile for the buckle it which adds to its aestheticappeal, aswell as minimizing the overall size andweight thereof; 7
It is to be understood that the specific construction of the improved safety belt buckle herein disclosed and described is presented for the purpose of explanation and illustration and is not intended to indicate limits of the invention, the scope of which is defined by the following claims.
What is claimed is: 1. A safety belt-buckle comprising a base member having a web portion with upstanding flanges on opposite sides with inturned edge portions extending in spaced generally parallel relationship to the web portion thereof, said base member having a latch plate retainer at one end thereof, a latch plate overlying the web portion of said base member in generally parallel relationship and having -one-end pivoted in the latch retainer of said base,
said latch plate having a latch face thereon, a belt tongue having a latch surface thereon and being insertable under the edge portions of said base member in overlying generally parallel relation to said latch plate, the latch face on said latch plate being engageable with the latch surface on said tongue to lock said tongue against movement outwardly of said .base, resilient means normally biasing said. latch .plate toward said tongue, and a release handle having apair. of oppositely laterally extending ears atone end thereof underlying the edge portions of said base member so as to be pivotally' supported by said base member adjacent the other end of said latch plate, said handle overlying said tongue, said handle being directly engageable withthe other end of said latch plate whereby rotation of said release handle relative to said base effects, disengagement of the latch face on said latch plate from the .latch surface on said tongue. 2. A safety belt buckle comprising a base member having a web portion with upstanding flanges on opposite sides with inturned edge portions extending in spaced generally parallel relationship to the web portion thereof, said base memberhaving a latch plate retainer at one end thereof and a pair of tongue strippers extendinginto closely spaced relation to the edge portions thereof, respectively, a latch plate overlying the web portion of said 'basemember in generally parallel relationship and having one end pivoted in the latch retainer of said base and a pair of apertures for the acceptance of the tongue-strippers on said 9 base, respectively, said latch plate having a laterally offset latch face on the opposite side thereof from the web portion of said base, a belt tongue having an aperture defining a latch surface, said belt tongue being insertable under the edge portions of said base member in overlying generally parallel relation to said latch plate, the latch face on said latch plate being engageable with the latch surface on said tongue to lock said tongue against movement outwardly of said base, resilient means between the web portion of said base and said latch plate for normally biasing said latch plate toward said tongue, and
a release handle having an intermediate portion pivotally engaged with the edge portions of said base member adjacent the other end of said latch plate and overlying said tongue, one end portion of said handle engaging the other end of said latch plate whereby movement of the other end portion of said release handle in one direction relative to said base effects disengagement of the latch face on said latch plate from the latch surface on said tongue and conditions said tongue for movement in the opposite direction relative to said base.
3. A safety belt buckle comprising a sheet metal base member having a web portion with upwardly folded flanges on opposite sides with inwardly folded edge portions extending in spaced generally parallel relationship to the web portion thereof, said base member having a latch plate retainer reentrantly folded at one end thereof, a sheet metal latch plate overlying the web portion of said base member in generally parallel relationship and having one end pivoted in the latch retainer of said base,
said latch plate having a laterally extending latch face thereon, a sheet metal belt tongue having a laterally extending latch surface thereon, said tongue being insertable under the edge portions of said base member in overlying generally parallel relation to said latch plate, the latch face on said latch plate being engageable with the latch surface on said tongue to lock said tongue against movement outwardly of said base, a leaf spring disposed between the web portion of said base and said latch plate and normally biasing said latch plate toward said tongue, and
a sheet metal release handle having a pair of ears on opposite sides thereof engaged under the edge portions of said base whereby said handle is pivotally supported by said base member adjacent the other end of said latch plate, said handle overlying said tongue, said handle engaging the other end of said latch plate so that rotation of said release handle relative to said base effects rotation of said latch plate and disengagement of the latch face on said latch plate from the latch surface on said tongue. 4. A safety belt buckle comprising a base member having a web portion with upstanding flanges on opposite sides with inturned edge portions extending in spaced generally parallel relationship to the web portion thereof, said base member havin a latch plate retainer I at one end thereof, a latch plate overlying the Web portion of said base member in generally parallel relationship and having one end pivoted in the latch retainer of said base,
said latch plate having a laterally ofiset latch face on the opposite side thereof from the web portion of said base, a belt tongue having an aperture defining a latch surface, said belt tongue being insertable under the edge portions of said base member in overlying generally parallel relation to said latch plate, the latch face on said latch plate being engageable with the latch surface on said tongue to lock said tongue against movement outwardly of said base, resilient means between the web portion of said base and said latch plate for normally biasing said latch plate toward said tongue, and a release handle extending generally parallel to said belt tongue and having an intermediate portion pivotally engaged under and interlocked with the edge portions of said base member adjacent the other end of said latch plate, one end portion of said handle relatively close to the intermediate portion thereof engaging the other end of said latch plate and the other end portion of said release handle being spaced relatively farther from the pivoted intermediate portion so as to provide a mechanical advantage to facilitate movement of the latch face on said latch plate laterally of said tongue upon rotation of said handle. 5. A safety belt buckle comprising a base member having a web portion with upstanding flanges on opposite sides thereof with inturned edge portions extending in spaced generally parallel relationship to the web portion there of, said base member having means at one end thereof for retaining a latch plate and means atanother end for retaining a release handle,
1 a latch plate having a'latch -thereon,-.said latch plate being disposed between the Web portion and edge portions of said base, resilient means between the web portion of said base and said latch plate for normally biasing said latch plate away from-the-web portion of said base, a release handle having a pair of oppositely laterally extending ears engaged under and retained by the edge portions of said base member whereby saidrelease handle is pivotally supported-bythe edge portions of said base memher, said handle being engageable with said latch plate to effectmovement thereof against the bias of said spring, and a belt tongue having a latch surface engageable with the latch on said latch plate, said belt tongue being insertable between said latch plate and handle, insertion of said tongue effecting a movement of said latch plate towards the web portion of said base against the bias of said spring whereby said belt tongue can be assembled with said base member without elfecting movement of said handle. 6. A safety belt buckle for a motor vehicle comprising abase member having a web portion with upstanding flanges on opposits sides thereof, said flanges having inturned edge portions extending in spaced generally parallel relationship to the web portion of said base for pivotally supporting a release handle, said base member having a latch plate retainer ---at one end thereof, a latch plate overlying the web portion of said base member in generally parallel relationship, said latch plate having one end pivoted in the latch retainer of said base and having a laterally extending latch face thereon,
, a belt tongue having alaterally extending latch surface thereon and insertable under the supporting means on said base member in overlying generally parallel relation to said latch plate, the latch face on said latchplate being engageable with the latch surface on said tongue to lock said tongue against movement outwardly of said base, a leaf spring disposed between the webportion of said base and said latch ,plateand normally biasing said latch plate toward said tongue, and
.a releasehandle ha ving an intermediate portion pivotally supported by the means on said base member and one end portion engaged with the 'otherend of said latch plate whereby inertia forces operative .on said latch plate attendant to sudden stoppage of a motor vehicle tend -to bias both said latch plate and said handle to. the latched condition. 7. A safetybelt-buckle comprising a base member having a. web portion with upstanding flanges 3 on opposite sides thereof with inturned edge portions -extending in spaced generally parallel relationship to the web portion thereof,
said basemember having means atone end'thereoffor retaining a latch plateagainst movement in one direction and means at an intermediate portion thereof :iorretaining-said latch plate and a re lease handle against movement in the opposite direction,
- a latch plate having a latch 3 thereon, said latchplate overlying the 'WCb'POI'tlOH of saidbase member and having means for restraining the release handle against movement in said one direction, albeit tongue having a latch surface engageable with the latch on said latch plate, resilient means between the web portion of said base and said latch plate for normally biasing said latch plate toward said, tongue, and a release handle pivotally supportedby said base member at the intermediate portion thereof, said handle being engageable with said latch plate to effect disengagementof the latch thereon from the latch sur face on said tongue, the edge portions of said base retaining said release handle, tongue, latch plate and resilient means against movement in a direction normal to said one direction whereby said base, latch plate, resilient means and release handle of said buckle are mutually interlocked in an assembled condition. 8. A safety belt buckle comprising a base member having means at. one end thereof for retaining a latch plate against movement in one direction, said base member having means ,for limiting movement of a belt tongue l in a direction normal to said one direction, said basemember having means at;an;intermediatepprtion for retaining a release handle and the latch plate against movement in the Opposite direc- ,tion, a latch plate engaged with the one end portion of said base and means forrestraining a release handle against movement in said one direction,
13 a belt tongue engageable with said latch plate, resilient means for normally biasing said latch plate in said normal direction toward the engaged condition with said tongue, movement of said latch plate and said tongue being limited by said limiting means,
a release handle pivotally supported by said base member at the intermediate portion thereof, said handle being engageable with said latch plate to effect disengagement thereof from said tongue, means for separating said latch plate and belt tongue upon movement of said latch plate in a direction opposite to said normal direction, and
a slide at the other end of said base having means for engaging a belt, said slide having means engageable with said base for restraining movement thereof in said opposite direction.
9. A safety belt buckle comprising a base member having a web portion with upstanding flanges on opposite sides, said flanges having inturned edge portions extending in spaced generally parallel relationship to the web portion thereof, said base member having a latch member retainer adjacent one end thereof, a latch member overlying the web portion of said base member in generally parallel relationship and having one end pivoted in the latch retainer of said base, said latch member having a latch face thereon, a belt tongue having a latch surface thereon, said belt tongue being insertable in said base member between said flanges and in generally parallel relation to said latch member, the latch face on said latch member being engageable with the latch surface on said tongue to lock said tongue against movement endwise outwardly of said base, resilient means normally biasing said latch member toward said tongue, means including said inturned edge portions for limiting movement of said latch and tongue away from said web, and a release handle having a pair of oppositely laterally extending projections at one end thereof underlying the edge portions of said base member so as to fulcrum on the underside of said edge portions, said handle having a portion operative to'disengage the latch face on said latch member from the latch surface on said tongue when the handle is rotated about said fulcrum.
10. A safety belt buckle comprising a sheet metal base member having a web portion with upwardly folded flanges on opposite sides, said flanges having inwardly folded edge portions extending in spaced generally parallel relationship to the web portion thereof, said base member having a latch plate retainer reentrantly folded at one end thereof, a sheet metal latch plate overlying the web portion of said base member in generally parallel relationship and having one end fulcrumed in the latch retainer of said base, said latch plate having a laterally extending latch face thereon, a sheet metal belt tongue having a laterally extending latch surface thereon, said tongue being insertable endwise under the edge portions of said base member and on the opposite side of said latch plate from said base, the latch face on said latch plate being engageable with the latch surface on said tongue to lock said tongue against movement endwise outwardly of said base, a sheet metal spring having at least a portion thereof disposed between the web portion of said base and said latch plate and normally biasing said latch plate toward said tongue, and a sheet metal release handle having a pair of projections on opposite sides thereof engaged under the edge portions of said base whereby said handle is fulcrumed by said projections on the underside of said edge portions adjacent the other end of said latch 14 plate, said handle overlying said tongue, and means including a portion of said handle which engages the latch plate for releasing the latch face thereon from the latch surface on said tongue when the handle is rotated about its fulcrum point.
11. A safety belt buckle comprising a base member having a web portion with upstanding flanges on opposite sides, said flanges having inturned edge portions extending in spaced generally parallel relationship to the web portion thereof, said base member having a latch member retainer adjacent one end thereof, a latch member overlying the web portion of said base member in generally parallel relationship and having one end pivoted in the latch retainer of said base, said latch member having a latch face thereon, a belt tongue having a latch surface thereon, said belt tongue being insertable in said base member between said flanges and in generally parallel relation to said latch member, the latch face on said latch member being engageable with the latch surface on said tongue to lock said tongue against movement endwise outwardly of said base, resilient means normally biasing said latch member toward said tongue, and a release handle having a pair of oppositely laterally extending projections at one end thereof underlying the edge portions of said base member so as to fulcrum on the underside of said edge portions, said handle having a portion operative to disengage the latch face on said latch member from the latch surface on said tongue when the handle is rotated about said fulcrum.
12. A safety belt buckle comprising a base memberv having a web portion with upstanding flanges on opposite longitudinally extending sides thereof, said flanges having inturned edge portions extending in spaced generally parallel relationship to the web portion of said base member, said base member having longitudinally spaced means thereon for retaining a latching means against movement in either direction longitudinally of said base, a latching means including a latch member having a latch face thereon and a spring, means including the edge portions of said base member for restraining move ment of said latching means away from the Web portion of said base member, a belt tongue having a latch surface engageable with the latch face on said latch member, said spring normally biasing said latch member toward said tongue, a release handle having oppositely laterally extending projections thereon extending under the edge portions of said base member so as to be pivotally supported by said base member, said handle being engageable with said latch member to eflect disengagement of the latch face thereon from the latch surface on said tongue, means on said latching means for restraining movement of said handle in one direction longitudinally of said base, and means supported by said base for restraining longitudinal movement of said handle in the direction opposite to said one direction whereby said base, latch means and release handle are mutually interlocked in an assembled condition.
References Cited in the file of this patent UNITED STATES PATENTS 401,880 Frantzen Apr. 23, 1889 1,607,085 Kilstrom Nov. 16, 1926 1,764,240 Blustein June 17, 1930 2,143,126 Honegger Jan. 10, 1939 2,862,268 Cushman Dec. 2, 1958 2,864,145 Elsner Dec. 16, 1958 2,919,481 Finken et al. Jan. 5, 1960 2,999,288 Warner et al. Sept. 12, 1961 FOREIGN PATENTS 670,672 France Aug. 24, 1929 1,072,643 France Mar. 17, 1954 464,786 Germany Aug. 27, 1928 81,813 Switzerland July 16, 1919

Claims (1)

  1. 7. A SAFETY BELT BUCLKE COMPRISING A BASE MEMBER HAVING. A WEB PORTION WITH UPSTANDING FLANGES ON OPPOSITE SIDES THEREOF WITH INTURNED EDGE PORTIONS EXTENDING IN SPACED GENERALLY PARALLEL RELATIONSHIP TO THE WEB PORTION THEREOF. SAID BASED MEMBER HAVING MEANS AT ONE END THEREOF FOR RETAINING A LATCH PLATE AGAINST MOVEMENT IN ONE DIRECTION AND MEANS AT AN INTERMEDIATE PORTION THEREOF FOR RETAING SAID LATCH PLATE AND A RELEASE HANDLE AGAINST MOVEMENT IN THE OPPOSITE DIRECTION, A LATCH PLATE HAVING A LATCH THEREON, SAID LATCH PLATE OVERLYING THE WEB PORTION OF SAID BASE MEMBER AND HAVING MEANS FOR RESTRAINING THE RELEASE HANDLE AGAINST MOVEMENT IN SAID ONE DIRECTION A BELT TONGUE HAVING A LATCH SURFACE ENGAGEABLE WITH THE LATCH ON SAID LATCH PLATE, A RESILIENT MEANS BETWEEN THE WEB PORTION OF SAID BASE AND SAID LATCH PLATE FOR NORMALLY BIASING SAID LATCH PLATE TOWARD SAID TONGUE, AND A RELEASE HANDLE PIVOTALLY SUPPORTED BY SAID BASE MEMBER AT THE INTERMEDIATE PORTION THEREOF, SAID HANDLE BEING ENGAGEABLE WITH SAID LATCH PLATE TO EFFECT DISENGAGEMENT OF THE LATCH THEREON FROM THE LATCH SURFACE ON SAID TONGUE, THE EDGE PORTIONS OF SAID BASE RETAINING SAID RELEASE HANDLE, TONGUE, LATCH PLATE AND RESILIENT MEANS AGAINST MOVEMENT IN A DIRECTION NORMAL TO SAID ONE DIRECTION WHEREBY SAID BASE, LATCH PLATE RESILIENT MEANS AND RELEASE HANDLE OF SAID BUCKLE ARE MUTUALLY INTERLOCKED IN AN ASSEMBLED CONDITION.
US207262A 1962-07-03 1962-07-03 Safety belt buckle Expired - Lifetime US3131451A (en)

Priority Applications (7)

Application Number Priority Date Filing Date Title
US207262A US3131451A (en) 1962-07-03 1962-07-03 Safety belt buckle
SE7302/63A SE301915B (en) 1962-07-03 1963-07-01
DEF40128A DE1246295B (en) 1962-07-03 1963-07-02 Closure buckle
GB26137/63A GB1039723A (en) 1962-07-03 1963-07-02 Safety belt buckle
FR940273A FR1366289A (en) 1962-07-03 1963-07-03 Buckle for seat belts
US366673A US3274655A (en) 1962-07-03 1964-03-12 Safety belt buckle
US26754D USRE26754E (en) 1962-07-03 1965-10-21 Safety belt buckle

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US207262A US3131451A (en) 1962-07-03 1962-07-03 Safety belt buckle

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US3131451A true US3131451A (en) 1964-05-05

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Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3242547A (en) * 1964-09-03 1966-03-29 Products Res Company Safety belt buckle
DE1266552B (en) * 1964-07-20 1968-04-18 Robert Cripps Fisher Closure buckle
US3408707A (en) * 1966-07-11 1968-11-05 Hemphill Desmond John Buckle for safety belts
US3491415A (en) * 1968-04-22 1970-01-27 American Safety Equip Safety belt buckle with twist bar
US3496615A (en) * 1966-08-24 1970-02-24 Cummings & Sander Inc Safety belt buckle
DE1557534B1 (en) * 1965-04-12 1971-07-08 Takezo Takada Buckle for seat belts
US4542563A (en) * 1983-02-18 1985-09-24 Trw Automotive Products, Inc. End release buckle
US4566160A (en) * 1981-04-13 1986-01-28 Irvin Industries, Inc. End release inverse clevis buckle
US5377393A (en) * 1993-09-03 1995-01-03 Trw Vehicle Safety Systems Inc. Seat belt buckle
US6948219B2 (en) 2002-05-31 2005-09-27 Graco Children's Products Inc. Latch system for child seat

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US401880A (en) * 1889-04-23 Clasp
CH81813A (en) * 1919-01-28 1919-07-16 Justin Bridevaux Clasp for jewelry pieces
US1607085A (en) * 1926-04-29 1926-11-16 Kilstrom Axel Clasp
DE464786C (en) * 1928-08-27 Franz Jordan Fa Closure for bracelets, necklaces, etc.
FR670672A (en) * 1929-03-01 1929-12-02 Closure, particularly intended for jewelry, and other applications
US1764240A (en) * 1929-02-21 1930-06-17 Blustein Abraham Safety spring clasp
US2143126A (en) * 1935-07-25 1939-01-10 Honegger Willy Buckle
US2862268A (en) * 1956-07-26 1958-12-02 Pacific Scient Aeroproducts Safety belt buckle
US2864145A (en) * 1955-10-03 1958-12-16 Mcjohn Corp Buckle
US2919481A (en) * 1955-11-14 1960-01-05 Gentex Corp Adjustable buckle
US2999288A (en) * 1955-11-23 1961-09-12 Capewell Mfg Company Buckle assembly

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US401880A (en) * 1889-04-23 Clasp
DE464786C (en) * 1928-08-27 Franz Jordan Fa Closure for bracelets, necklaces, etc.
CH81813A (en) * 1919-01-28 1919-07-16 Justin Bridevaux Clasp for jewelry pieces
US1607085A (en) * 1926-04-29 1926-11-16 Kilstrom Axel Clasp
US1764240A (en) * 1929-02-21 1930-06-17 Blustein Abraham Safety spring clasp
FR670672A (en) * 1929-03-01 1929-12-02 Closure, particularly intended for jewelry, and other applications
US2143126A (en) * 1935-07-25 1939-01-10 Honegger Willy Buckle
US2864145A (en) * 1955-10-03 1958-12-16 Mcjohn Corp Buckle
US2919481A (en) * 1955-11-14 1960-01-05 Gentex Corp Adjustable buckle
US2999288A (en) * 1955-11-23 1961-09-12 Capewell Mfg Company Buckle assembly
US2862268A (en) * 1956-07-26 1958-12-02 Pacific Scient Aeroproducts Safety belt buckle

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1266552B (en) * 1964-07-20 1968-04-18 Robert Cripps Fisher Closure buckle
US3242547A (en) * 1964-09-03 1966-03-29 Products Res Company Safety belt buckle
DE1267897B (en) * 1964-09-03 1968-05-09 American Safety Equip Buckle for seat belts
DE1557534B1 (en) * 1965-04-12 1971-07-08 Takezo Takada Buckle for seat belts
US3408707A (en) * 1966-07-11 1968-11-05 Hemphill Desmond John Buckle for safety belts
US3496615A (en) * 1966-08-24 1970-02-24 Cummings & Sander Inc Safety belt buckle
US3491415A (en) * 1968-04-22 1970-01-27 American Safety Equip Safety belt buckle with twist bar
US4566160A (en) * 1981-04-13 1986-01-28 Irvin Industries, Inc. End release inverse clevis buckle
US4542563A (en) * 1983-02-18 1985-09-24 Trw Automotive Products, Inc. End release buckle
US5377393A (en) * 1993-09-03 1995-01-03 Trw Vehicle Safety Systems Inc. Seat belt buckle
US6948219B2 (en) 2002-05-31 2005-09-27 Graco Children's Products Inc. Latch system for child seat

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