Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
278 words
Device for stretching a band forming part of a safety belt for a vehicle, said device shortening the active portion of the safety belt by taking up any slack of the band and stretching same towards the body of a user in response to abnormal changes of speed of the vehicle, comprising a winding-up core for the band, a housing forming a bearing for one end of said core, a bearing for the other end of said core whereby said core is rotatably mounted, a cam provided at said one end of said core, and located within said housing, said cam having a surface extending substantially in a radial direction, an arm journalled in said housing outside of the outer contour of the cam and pivotable in a plane transverse to the longitudinal axis of the winding-up core between a position in the path of movement of the cam and a position outside of said path of movement, the free end of said arm being positioned in the inactive condition of said device in said path of movement of said cam to define with said cam surface and the walls of said housing a closed expansible chamber, a charge supported in said free end of said arm, which charge when activated produces a gas pressure, and means for activating said charge in response to abnormal changes of speed of the vehicle whereby the pulse of the gas pressure produced acts on said cam surface and causes said chamber to expand, thereby rotating said cam and moving said arm to its position outside of the path of movement of said cam and rotating said core in the winding-up direction.
Claim 2
Dependent Claim
278 words
Device for stretching a band forming part of a safety belt for a vehicle, said device shortening the active portion of the safety belt by taking up any slack of the band and stretching same towards the body of a user in response to abnormal changes of speed of the vehicle, comprising a winding-up core for the band, a housing forming a bearing for one end of said core, a bearing for the other end of said core whereby said core is rotatably mounted, a cam provided at said one end of said core, and located within said housing, said cam having a surface extending substantially in a radial direction, an arm journalled in said housing outside of the outer contour of the cam and pivotable in a plane transverse to the longitudinal axis of the winding-up core between a position in the path of movement of the cam and a position outside of said path of movement, the free end of said arm being positioned in the inactive condition of said device in said path of movement of said cam to define with said cam surface and the walls of said housing a closed expansible chamber, a charge supported in said free end of said arm, which charge when activated produces a gas pressure, and means for activating said charge in response to abnormal changes of speed of the vehicle whereby the pulse of the gas pressure produced acts on said cam surface and causes said chamber to expand, thereby rotating said cam and moving said arm to its position outside of the path of movement of said cam and rotating said core in the winding-up direction.
Claim 3
Dependent Claim
79 words
Device according to claim 1, wherein said expansible chamber has the shape of an annular groove, one end wall being comprised of the free end of said arm and another end wall being comprised of said cam surface, the chamber inside being defined by a cylindrical end portion of the core from which the cam projects and outwardly being defined by a cylindrical end wall of the housing to which the top of the cam has a tight fit.
Claim 4
Dependent Claim
32 words
Device according to claim 2, wherein said arm has a longitudinal bottom hole which debouches at the free end of said arm which faces said cam surface, said hole enclosing said charge.
Claim 5
Dependent Claim
15 words
Device according to claim 3, wherein said charge is an electrically ignitable gun powder charge.
Claim 6
Dependent Claim
52 words
Device according to claim 1, wherein said arm has a cylindrical bearing portion journalled in a groove provided in said housing, one end of said groove being formed by a detachable end lid which also forms an outer end wall of said housing, whereby said end of the groove can be opened.
Claim 7
Dependent Claim
119 words
Device according to claim 1, wherein there is provided a one way blocking means for said winding-up core located in a second housing which also forms said bearing for the other end of said core, said blocking means comprising a ratchet wheel on said core and rotatable therewith, a pawl having a free end cooperable with said wheel and being in the form of an arm having a cylindrical bearing portion extending parallel to said core, said bearing portion being journalled in a groove of a correspondingly cylindrical shape provided in said second housing, one end wall of said groove being removable to open same to permit mounting and demounting of said pawl by axial displacement of the same.
Claim 8
Dependent Claim
46 words
Device according to claim 3, wherein the center axis of said bottom hole is located on the same side of the pivoting center of said arm as the core, whereby the arm when said charge is activated is pressed against the end portion of the core.
Claim 9
Dependent Claim
25 words
Device according to claim 1, wherein said arm is loaded by spring pressure tending to keep same biased towards the end portion of said core.