HINGE CONSTRUCTION WITH MULTI-LAYER TORSION BAR SPRING

Abstract

A hinge assembly (600) for rotatably mounting a first part (202a) to a second part (204a) to permit rotational movement of the first part relative to the second part between a closed position and an open position, the hinge assembly comprising: (a) a shaft (620) having at least a first end portion (626) and a second end portion (622), (b) an adapter (640) attached to the first end portion (626) of the shaft (620), the adapter (640) being attached to the first end portion (626) of the shaft (620) such that it is restricted to rotating with the shaft (620) as a unit, the adapter (640) being adapted for fixed attachment to the first part (202a) to move with the first part (202a) as a unit, (c) a hinge base (602) adapted for fixed attachment to the second part (204a) to move with the second part (204a) as a unit, wherein the hinge base (602) has at least one bearing surface (604, 606) which rotatably supports the shaft (620) such that when the adapter (640) is attached to the first part (202a) and the hinge base (602) is attached to the second part (204a), the first part is rotatably attached to the second part such that the first part can pivotally move relative to the second part between a closed position and an open position, (d) a friction mechanism (730) for frictionally resisting rotational movement relative to the hinge base (602), (e) an end piece (660) adapted to be held in fixed relationship relative to the hinge base (602), and (f) a torsion bar spring (680) extending between the end piece (660) and the second end portion (622) of the shaft (620), the torsion bar spring (680) having a first end (682), a second end (684), a resilient restoring force, and a longitudinal axis, the first end (682) of the torsion bar spring (680) being constrained against rotation relative to the shaft (620), the second end (684) of the torsion bar spring (680) being constrained against rotation relative to the end piece (660) about the longitudinal axis of the torsion bar spring.is clamped so that rotation of the shaft (620) relative to the end piece (660) causes the torsion bar spring (680) to twist about its longitudinal axis when the shaft was initially in a neutral position, so that the torsion bar spring (680) tends to store energy and exert a force to return the shaft (620) to its neutral position due to the restoring force of the torsion bar spring (680). (g) a housing (677) extending between the hinge base (602) and the end piece (660), the housing (677) having a bore through which the torsion bar spring (680) extends, the housing (677) being attached at one end to the hinge base (602) and at the other end to the end piece (660) to thereby ensure that the end piece (660) is held in a fixed relationship relative to the hinge base (602), wherein the friction mechanism (730) is arranged closer to the end of the housing (677) which is attached to the hinge base (602) than to the end of the housing (677) which is attached to the end piece (660), and wherein the end piece (660) has two lateral projections (662) and a sleeve (664), the projections (662) of the end piece (660) engaging and fitting into corresponding notches (675) provided at one end of the outer shell or housing (677) to prevent relative rotation between the end piece (660) and the shell or housing (677).

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention

[0001] The present invention relates to a hinge assembly for pivotally connecting a first part to a second part to permit pivotal movement of the first part relative to the second part between a closed position and an open position. 2. Description of the state of the art

[0002] Hinge assemblies for pivotally securing a first part to a second part to permit pivotal movement of the first part relative to the second part between a closed and an open position are known in the art. In particular, spring-loaded hinge assemblies are known that assist in opening the first part relative to the second part by storing energy in a spring during the closing process, as shown in U.S. Patent No. 7,055,215 B1 to Ligtenberg et al., issued June 6, 2006. However, these hinges require specially machined springs that are extremely expensive and complicated to manufacture.The multi-layer torsion bar of the present invention, which functions to assist the opening of the first part relative to the second part by storing energy during the closing process, drastically reduces the cost and complexity of spring manufacturing while providing the same functionality and performance. These and other advantages of the present invention will become apparent from the following description and figures. No hinge structure is known in the prior art that teaches or suggests the unique features of the present invention to achieve the benefits of the present invention.

[0003] US 7055215 B1 shows a friction hinge with a rotating shaft and friction elements for position stabilization. This design allows a movable element to be held in position at different angular positions against a restoring moment. Friction surfaces are used to generate controlled anti-rotation forces.

[0004] US 3022536 A describes a hinge mechanism in which a spring serves to assist a lid element during the opening process. A hinge shaft and an adapter are provided, which are firmly connected to a housing part and establish a connection with the part to be moved.

[0005] US Pat. No. 5,771,540 A discloses a spring mechanism with a multi-layer, laminated torsion bar spring, each end of which is clamped into a component. This torsion spring is designed to store energy through twisting and exert a restoring effect on a moving element.

[0006] US 4348786 A discloses a hinge with friction elements that can be used to hold a hinged part in various positions. The hinge comprises a rotatably mounted shaft, which is subjected to friction forces to ensure positional stability. SUMMARY OF THE INVENTION

[0007] The present invention is directed to a hinge assembly for pivotally securing a first member to a second member to permit pivotal movement of the first member relative to the second member between a closed position and an open position. The hinge assembly of the present invention includes a spring that assists in opening the first member relative to the second member by storing energy in the spring during the closing operation. The spring is comprised of a unique design of a multi-layer torsion bar. The hinge assembly also includes a friction mechanism that applies sufficient frictional force to the hinge shaft to allow the first member to be held in a range of desired angular positions on either side of the angular position corresponding to a relaxed state of the hinge spring, including the angular position corresponding to the relaxed state of the hinge spring.

[0008] Accordingly, it is an object of the present invention to provide a multi-layer torsion bar spring. Another object of the present invention is to provide a spring-assisted friction hinge that utilizes a multi-layer torsion bar spring.

[0009] Another object of the invention is to provide a spring-assisted friction hinge which uses a torsion bar spring.

[0010] These and other objects of the present invention will become apparent from the accompanying description and drawings. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is an external view of a hinge assembly showing the hinge assembly applied to a laptop computer with the lid of the laptop computer in the closed position. Fig. 2 is a view of the hinge assembly showing the application of the hinge assembly in use with a laptop computer, wherein the lid of the laptop computer is in an angular position relative to the base of the laptop computer corresponding to the relaxed state of the hinge spring. Fig. 3 is a view of the hinge assembly showing the hinge assembly in application to a laptop computer with the lid of the laptop computer in an angular position relative to the base of the laptop computer corresponding to the fully open state of the laptop computer lid. Fig. Figure 4 is a partial view showing the installation of the hinge assembly on a laptop computer. Fig. 5 is a partial cross-sectional view of the laptop computer to illustrate the installation of the hinge assembly to the laptop computer. Fig. 6-13 are views of the hinge assembly showing the hinge adapter in an angular position relative to the base of the hinge assembly corresponding to the relaxed state of the hinge spring. Fig. 14 is an exploded view of the hinge assembly. Fig. 15 is an isometric view of the hinge assembly showing the hinge adapter in an angular position relative to the base of the hinge assembly corresponding to the relaxed state of the hinge spring. Fig. 16 is an isometric view of the hinge assembly showing the hinge adapter in an angular position relative to the base portion of the hinge assembly corresponding to the relaxed state of the hinge spring, with the spring cover removed to show the multi-layer torsion bar spring in its relaxed state. Fig. Figure 17 is an isometric view of the hinge assembly showing the hinge adapter in an angular position relative to the base of the hinge assembly corresponding to the relaxed state of the hinge spring. Fig. 18 is an isometric view of the hinge assembly showing the hinge adapter in an angular position relative to the base portion of the hinge assembly corresponding to the relaxed state of the hinge spring, the hinge assembly being shown in section to reveal its internal details. Fig. 19 is an isometric view of the hinge assembly showing the hinge adapter in an angular position relative to the base portion of the hinge assembly, showing the fully twisted hinge spring with the spring cover and cap removed, and with the end portion of the hinge assembly shown in section to show the multi-layer torsion bar spring in its fully twisted state. Fig. Figure 20 is an isometric view of the hinge assembly showing the hinge adapter in an angular position relative to the base portion of the hinge assembly corresponding to the fully open position of the laptop computer lid. Fig. 21 is an isometric view of the hinge assembly showing the hinge adapter in an angular position relative to the base portion of the hinge assembly corresponding to the fully open position of the laptop computer lid, with the spring cover removed to show the multi-layer torsion bar spring in a twisted state corresponding to the fully open position of the laptop computer lid. Fig. 22 is a cross-sectional view of the hinge assembly taken along line AA in Fig. 26 to reveal the inner details. Fig. Figure 23 is an isometric view of the hinge assembly showing the hinge adapter in an angular position relative to the base portion of the hinge assembly corresponding to the fully twisted condition of the hinge spring. Fig. Figure 24 is an isometric view of the hinge assembly showing the hinge adapter in an angular position relative to the base portion of the hinge assembly corresponding to the fully twisted condition of the hinge spring, with the spring cover removed to show the multi-layer torsion bar spring in its fully twisted condition. Fig. Figure 25 is an enlarged fragmentary view showing the multi-layer torsion bar spring in its fully twisted state. Fig. 26-27 are top and side views of the hinge assembly to show the location of the section lines that define the cross-sectional views of the Fig. 22 and 28-35 show. Fig. 28 is a cross-sectional view of the hinge assembly with a section corresponding to the line DD in Fig. 27, which shows the hinge adapter in an angular position relative to the base part of the hinge assembly that corresponds to the fully open position of the laptop computer lid. Fig. 29 is a cross-sectional view of the hinge structure taken along line DD in Fig. 27, which shows the hinge adapter in an angular position relative to the base part of the hinge assembly corresponding to the relaxed state of the hinge spring. Fig. 30 is a cross-sectional view of the hinge structure taken along line DD in Fig. 27, which shows the hinge adapter in an angular position relative to the base part of the hinge assembly corresponding to the fully twisted state of the hinge assembly. Fig. 31 is a cross-sectional view of the hinge structure taken along line CC in Fig. 27, which shows the hinge adapter in an angular position relative to the base part of the hinge assembly that corresponds to the fully open position of the laptop computer lid. Fig. 32 is a cross-sectional view of the hinge structure taken along line CC in Fig. 27, which shows the hinge adapter in an angular position relative to the base part of the hinge assembly corresponding to the relaxed state of the hinge spring. Fig. 33 is a cross-sectional view of the hinge structure taken along line CC in Fig. 27, which shows the hinge adapter in an angular position relative to the base part of the hinge assembly corresponding to the fully twisted state of the hinge spring. Fig. 34 is a cross-sectional view of the hinge assembly taken along line BB in Fig. 27, which shows the hinge adapter in an angular position relative to the base part of the hinge assembly corresponding to the relaxed state of the hinge spring. Fig. 35 is a cross-sectional view of the hinge assembly taken along line BB in Fig. 27, which shows the hinge adapter in an angular position relative to the base part of the hinge assembly corresponding to the fully twisted state of the hinge spring. Fig. 36-41 are views of the hinge assembly adapter for attaching the hinge assembly to a first part, such as a laptop computer lid. Fig. 42-49 are views of the end cap of the spring of the hinge assembly for axially confining one end of the multi-layer torsion bar spring relative to the hinge shaft. Fig. 50-57 are views of the end piece of the hinge assembly for limiting rotation of one end of the multi-layer torsion bar spring relative to a second part, such as a base of a laptop computer. Fig. 58-62 are views of a leaf of the multi-layer torsion bar spring of the hinge assembly. Fig. 63-70 are views of the hinge base of the hinge assembly. Fig. 71-76 are views of the hinge shaft of the hinge assembly. Fig. 77-82 are views of the friction element of the friction mechanism of the hinge assembly. Fig. 83-89 are views of the cover of the friction mechanism of the hinge assembly. Fig. 90-95 are views of the channel insert of the friction mechanism of the hinge assembly. Fig. 96-102 are views of the hinge assembly torsion bar spring cover. Fig. 103 is a view of a second embodiment of the hinge assembly of the present invention, showing the hinge assembly on a laptop computer with the lid of the laptop computer in the closed position. Fig. 104 is a view of the second embodiment of the hinge assembly of the present invention, showing the hinge assembly attached to a laptop computer with the lid of the laptop computer in an angular position relative to the base of the laptop computer corresponding to the relaxed state of the hinge spring. Fig. 105 is a view of the second embodiment of the hinge assembly of the present invention, showing the hinge assembly attached to a laptop computer with the lid of the laptop computer in an angular position relative to the base of the laptop computer corresponding to the fully open state of the computer lid. Fig. 106-107 are partial views showing the installation of the second embodiment of the hinge assembly of the present invention on a laptop computer. Fig. 108 is a partial cross-sectional view of the laptop computer to show the installation of the second embodiment of the hinge assembly of the present invention to the laptop computer. Fig. 109-112 are views of the second embodiment of the hinge assembly of the present invention showing the hinge adapter in an angular position relative to the base of the hinge assembly corresponding to the relaxed state of the hinge spring. Fig. 113 is a view of the second embodiment of the hinge assembly of the present invention showing the hinge adapter in an angular position relative to the base of the hinge assembly corresponding to the relaxed state of the hinge spring and with the outer wrap and inner sleeves removed to show the torsion bar spring. Fig. 114-115 are cross-sectional views of the second embodiment of the hinge assembly of the present invention showing the hinge adapter in an angular position relative to the base of the hinge assembly corresponding to the relaxed state of the hinge spring. Fig. 116-117 are exploded views of the second embodiment of the hinge assembly of the present invention. Fig. 118 is an isometric view of the second embodiment of the hinge assembly of the present invention showing the hinge adapter in an angular position relative to the base portion of the hinge assembly corresponding to the closed state of the hinge assembly and the fully twisted state of the hinge spring. Fig. 119-121 are views of the second embodiment of the hinge assembly of the present invention showing the hinge adapter in an angular position relative to the base portion of the hinge assembly corresponding to the closed condition of the hinge assembly and the fully twisted condition of the hinge spring, the illustrations being partially broken away to reveal internal details. Fig. 122 is an isometric view of the second embodiment of the hinge assembly of the present invention, showing the hinge adapter in an angular position relative to the base portion of the hinge assembly corresponding to the open position of the laptop computer lid. Fig. 123 is a view of the second embodiment of the hinge assembly of the present invention showing the hinge adapter in an angular position relative to the base portion of the hinge assembly corresponding to the fully open position of the laptop computer lid, and partially broken away to reveal internal details. Fig. 124 is a cross-sectional view of the second embodiment of the hinge structure of the present invention taken along line BB in Fig. 109, which shows the hinge adapter in an angular position relative to the base portion of the hinge assembly corresponding to the fully closed position of the laptop computer lid. Fig. 125 is a cross-sectional view of the second embodiment of the hinge structure of the present invention taken along line BB in Fig. 109, which shows the hinge adapter in an angular position relative to the base part of the hinge assembly corresponding to the relaxed state of the hinge assembly. Fig. 126 is a cross-sectional view of the second embodiment of the hinge structure of the present invention taken along line BB in Fig. 109, which shows the hinge adapter in an angular position relative to the base portion of the hinge assembly corresponding to the fully open position of the laptop computer lid. Fig. 127 is a cross-sectional view of the second embodiment of the hinge structure of the present invention taken along line CC in Fig. 109, which shows the hinge adapter in an angular position relative to the base portion of the hinge assembly corresponding to the fully closed position of the laptop computer lid. Fig. 128 is a cross-sectional view of the second embodiment of the hinge structure of the present invention taken along line CC in Fig. 109, which shows the hinge adapter in an angular position relative to the base part of the hinge assembly corresponding to the relaxed state of the hinge assembly. Fig. 129 is a cross-sectional view of the second embodiment of the hinge structure of the present invention taken along line CC in Fig. 109, which shows the hinge adapter in an angular position relative to the base portion of the hinge assembly corresponding to the fully open position of the laptop computer lid. Fig. 130 is a cross-sectional view of the second embodiment of the hinge structure of the present invention taken along line DD in Fig. 109, which shows the hinge adapter in an angular position relative to the base portion of the hinge assembly corresponding to the fully closed position of the laptop computer lid. Fig. 131 is a cross-sectional view of the second embodiment of the hinge structure of the present invention taken along line DD in Fig. 109, which shows the hinge adapter in an angular position relative to the base part of the hinge assembly, which corresponds to the relaxed state of the hinge assembly. Fig. 132 is a cross-sectional view of the second embodiment of the hinge structure of the present invention taken along line DD in Fig. 109, which shows the hinge adapter in an angular position relative to the base portion of the hinge assembly corresponding to the fully open position of the laptop computer lid. Fig. 133 is a cross-sectional view of the second embodiment of the hinge structure of the present invention taken along line EE in Fig. 109, which shows the hinge adapter in an angular position relative to the base portion of the hinge assembly corresponding to the fully closed position of the laptop computer lid. Fig. 134 is a cross-sectional view of the second embodiment of the hinge structure of the present invention taken along line EE in Fig. 109, which shows the hinge adapter in an angular position relative to the base part of the hinge assembly, which corresponds to the relaxed state of the hinge assembly. Fig. 135 is a cross-sectional view of the second embodiment of the hinge structure of the present invention taken along line EE in Fig. 109, which shows the hinge adapter in an angular position relative to the base portion of the hinge assembly corresponding to the fully open position of the laptop computer lid. Fig. 136-142 are views of the adapter of the second embodiment of the hinge assembly of the present invention for attaching the hinge assembly to a first part, such as a lid or top of a laptop computer. Fig. 143-150 are views of the first spring end cap or retainer of the second embodiment of the hinge assembly of the present invention for axially confining or terminating one end of the multi-layer torsion bar spring relative to the hinge base member. Fig. 151-158 are views of the end or retainer of the second spring end of the second embodiment of the hinge assembly of the present invention for axially confining or encompassing one end of the multi-layer torsion bar spring with respect to the hinge shaft. Fig. 159-162 are views of a leaf of the multi-layer torsion bar spring of the second embodiment of the hinge assembly of the present invention. Fig. 163-170 are views of the hinge base portion of the second embodiment of the hinge assembly of the present invention, which also forms the friction mechanism of the second embodiment of the hinge assembly of the present invention. Fig. 171-178 are views of the hinge shaft of the second embodiment of the hinge assembly of the present invention. Fig. 179-186 are views of the outer casing covering the torsion bar spring of the second embodiment of the hinge assembly of the present invention. Fig. 187-194 are views of the inner torsion bar spring covers or sleeves of the second embodiment of the hinge assembly of the present invention, which fit between the outer shell and the torsion bar spring.

[0011] Similar reference numerals consistently designate corresponding features throughout the accompanying drawings. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] According to the Fig. 1-102, a hinge assembly 300, 500 is described for pivotally mounting a first part to a second part to enable pivotal movement of the first part relative to the second part between a closed and an open position. According to the Fig. 1-5, two hinge assemblies 300 and 500 are shown in use, attaching the lid 204 of a laptop computer 200 to the laptop computer base 202. The laptop lid 204 typically houses the laptop screen 206, and its angular position relative to the laptop base 202 should be adjustable within a range of angular positions suitable for people of different sizes to comfortably view the laptop screen 206.

[0013] Hinge assembly 300 is a left hinge assembly, and hinge assembly 500 is a right hinge assembly. Right hinge assembly 500 is a mirror image of hinge assembly 300 with respect to a plane perpendicular to the longitudinal axes of the shafts of each of the hinge assemblies, midway between the two hinge assemblies. Accordingly, only one hinge assembly 300 will be described in detail. Laptop lid 204 is typically releasably secured in the closed position relative to laptop base 202 by a latch of some type (not shown). The latch is operable by a user to release laptop lid 204 for pivotal movement to the open position relative to laptop base 202.

[0014] The hinge assembly 300 can be used to pivotally attach a first part to a second part to enable pivotal movement of the first part relative to the second part between a closed and an open position. In the illustrated example, the first part is a laptop lid 204 and the second part is a laptop base 202. The hinge assembly 300 includes an elongated shaft 320, an adapter 340, a hinge base 302, a friction mechanism 430, an end piece 360, a torsion bar spring 380, a cap 400, and a torsion bar cover 420.

[0015] According to the Fig. 1-35 and 71-76, the elongated shaft 320 has at least one end portion 326, a second portion 324, and a head portion 322. The first end portion 326 of the shaft 320 is provided with a plurality of elongated teeth 328 of triangular cross-section, which are evenly distributed along the circumference of the first end portion 326 of the shaft 320. Each of the plurality of elongated teeth 328 extends over at least most of the length of the first end portion 326 of the shaft 320. In the example shown, the second portion 324 of the shaft 320 has a larger diameter compared to the first end portion 326. The head portion 322 of the shaft 320 has the shape of a cylindrical disk with a larger diameter than the second portion 324. The head portion 322 of the shaft 320 has a slot 330 which extends transversely, ie perpendicular to the longitudinal axis of the shaft 320.The head portion 322 of the shaft 320 has a pair of prongs 332 projecting from the head portion 322 on either side of the slot 330. The prongs or pins 332 extend from the head portion 322 of the shaft 320 in a direction parallel to the longitudinal axis of the shaft 320 and away from the first end portion 326 and the second portion 324. The prongs 332 have a plurality of ribs 334 provided on their outer surfaces. In the illustrated example, the ribs 334 are curved and have a sawtooth profile in cross-section.

[0016] The adapter 340 is attached to the shaft 320 at the first end portion 326 of the shaft 320. The adapter 340 is attached to the first end portion 326 of the shaft 320 such that the adapter 340 is restricted to rotating with the shaft 320 as a unit. The adapter 340 is configured for attachment to the first part, in the illustrated example, the laptop lid 204, to move with the first part as a unit. According to the Fig. 1-35 and 36-41, the adapter 340 has a main portion 342, which is rectangular in plan view with two rounded corners. The main portion 342 of the adapter 340 is provided with a plurality of holes 344 to enable the adapter 340 to be securely attached to the first part, for example, the laptop cover 204, using screws 346.

[0017] The adapter 340 has a bore 348 provided on one side in the rectangular main portion 342. The bore 348 of the adapter 340 is designed to receive the first end portion 326 of the shaft 320 in an interference fit (tight fit) such that the shaft 320 is securely attached to the adapter 340 and the shaft 320 and the adapter 340 are connected for rotation as a unit. The teeth 328 on the end portion 326 of the shaft help connect the shaft 320 for rotation with the adapter 340 by providing a tighter grip between the inner surface of the bore 348 of the adapter 340 and the outer surface of the first end portion 326 of the shaft 320.The bore 348 of the adapter 340 and the toothed outer surface of the first end portion 326 of the shaft 320 thus form the means for securely attaching the shaft 320 to the adapter 340 and for coupling the shaft 320 to the adapter 340 for common rotation in the illustrated embodiment.

[0018] Many other suitable means could also be used for securely attaching the shaft 320 to the adapter 340 and connecting the shaft and adapter for rotation together. The outer surface of the first end portion 326 of the shaft 320 may be smooth, and it may be inserted into the bore 348 in a tight fit to secure the shaft 320 and adapter 340 together and connect them together. A key that cooperates with slots in the shaft 320 and the bore 348 may be used to secure the shaft 320 and adapter 340 together and connect them together. Fasteners that extend through the wall of the bore 348 and either extend into corresponding bores in the shaft 320 or are in frictional engagement with the shaft 320 may be used to secure and connect the shaft 320 and adapter 340 together.Additionally, the adapter 340 may be clamped to the shaft 320 using a clamping arrangement, for example, by providing an elongated slot extending completely through the wall of the bore 328 and by providing one or two flanges on the elongated slot with screws that can be tightened to draw the edges of the longitudinal slot together and clamp the adapter 340 onto the shaft 320.

[0019] The hinge base 302 is designed for fixed attachment to the second part, in this case the laptop base 202, so that it moves with the second part as a unit. The hinge base 302 has at least one bearing surface 304, 306 that rotatably receives the shaft 320 so that when the adapter 340 is attached to the first part and the hinge base 302 is attached to the second part, the first part is rotatably attached to the second part so that the first part can pivotally move relative to the second part between a closed and an open position. In the illustrated example, the first and second parts are the laptop lid 204 and the laptop base 202, respectively. The bearing surface of the hinge base 302 supports a portion of the second part 324 of the shaft 320 to provide rotatable support of the shaft 320 through the hinge base 302.

[0020] According to the Fig. 1-35 and 63-70, the hinge base 302 in the illustrated example has two bearing surfaces 304 and 306. The hinge base 302 has a side 308 closest to the adapter 340 and a side 310 farthest from the adapter 340. The side 308 has an opening 312 that allows the shaft 320 to extend outward from the hinge base 302 to the adapter 340. The side 310 has an opening 314 that allows the head portion 322 of the shaft 320 to be at least partially exposed and accessible from the side of the hinge base 302 farthest from the adapter 340. A curved recess 316 is provided along a portion of the edge of the opening 314. The recess 316 has end walls 318 and 319. The hinge base 302 has a flange 301 which has a plurality of holes orholes 303 to enable the hinge base 302 to be attached to the second part, for example the laptop base 202, by screws 305.

[0021] According to the Fig. 1-35, 63-70, and 77-95, the hinge assembly 300 is provided with a friction mechanism 430 to provide frictional resistance to rotational movement of the shaft 320 relative to the hinge base 302. The friction mechanism 430 is supported by the hinge base 302. The friction mechanism 430 lies between the bearing surfaces 304 and 306. The friction mechanism 430 includes a plurality of friction elements 440, a channel insert, and a friction mechanism cover 460. The hinge base 302 has a channel 307 extending between the bearing surfaces 304 and 306 in a direction parallel to the longitudinal axis of the shaft 320. The friction elements 440 are of the symmetrical friction clamp type and have a C-shaped portion 442 and a pin 444. The pin 444 protrudes from the outer surface of the C-shaped part 442 at a location opposite the gap between the tips 446 and 448 of the C-shaped part 442.The friction elements 440 engage the portion of the second section 324 of the shaft 320 that extends between the bearing surfaces 304 and 306. The inner radius of the C-shaped portion 442 is smaller than the radius of the outer surface of the second section 324 of the shaft 320, so that the C-shaped portion 442 expands when placed around the second section 324 of the shaft 320. The compliance of the C-shaped portion 442 of the friction elements 440 causes the C-shaped portions 442 of the friction elements 440 to exert a gripping force on the second section of the shaft 320.

[0022] The channel insert 450 fits into the channel 307. The channel insert 450 is U-shaped in cross-section and extends the length of the channel 307. The pins 444 of the friction elements 440 are received in the channel insert 450 and, accordingly, also in the channel 307 to prevent the friction elements 440 from rotating with the shaft 320. The friction elements 440 are thus prevented from rotating relative to the hinge base 302. The gripping force exerted on the shaft 320 by the C-shaped portions 442 of the friction elements 440 creates a frictional moment that resists rotational movement of the shaft 320 relative to the hinge base 302. The friction torque generated by the friction elements 440 can be adjusted to any specifically specified value for a particular application by adjusting the geometry, number, and material of the friction elements 440.The friction mechanism cover 460 has a C-shaped cross-section and extends the length of the gap between the bearing surfaces 304 and 306. The edges of the friction mechanism cover 460 seal against the outer surfaces of the C-shaped portions 442 of the friction elements 440 and the portions of the hinge base 302 that form the bearing surfaces 304 and 306. The friction mechanism cover 460 keeps dirt and abrasive particles out of the friction mechanism 430 and keeps lubricant, which is required to ensure smooth hinge operation and prevent premature failure of the friction element, enclosed within the friction mechanism 430.The channel insert 450 is made of a relatively harder material compared to the hinge base 302 and acts to evenly distribute forces exerted by the pins of the friction elements 440 across the walls of the channel 307 so that the pins of the friction elements 440 do not dig into the channel 307 and deform it.

[0023] The end piece 360 ​​is designed for fixed attachment to the second part, in this case the laptop base 202, to move with the second part as a unit. The end piece 360 ​​has a flange 362 and a sleeve 364. The sleeve 364 has a front opening 366, a rear wall 368, side edges 370 and 372, a top edge 374, and a bottom edge 376. The front opening 366 is rectangular. The flange 362 of the end piece 360 ​​has a plurality of holes 378 to enable the end piece 360 ​​to be securely attached to the second part, for example, the laptop base 202, using screws 379. Fig. 1-5 show the end piece 360 ​​attached to the laptop base 202.

[0024] According to the Fig. 1-35 and 42-62, the torsion bar spring 380 extends from the end piece 360 ​​to the head portion 322 of the shaft 320. The torsion bar spring 380 has a first end 382 and a second end 384. The torsion bar spring is resiliently compliant and has a longitudinal axis. The first end 382 of the torsion bar spring 380 is clamped to rotate with the shaft 320 as a unit. The second end 384 of the torsion bar spring 380 is constrained by the end piece 360 ​​such that there is virtually no relative rotation between the end piece 360 ​​and the second end 384 of the torsion bar spring 380 about the longitudinal axis of the torsion bar spring 380, such that rotation of the shaft 320 relative to the end piece 360 ​​causes the torsion bar spring 380 to twist about its longitudinal axis when the shaft 320 is initially in a neutral position.The neutral position refers to the position of any part of the hinge assembly 300 corresponding to the relaxed state of the torsion bar spring 380. The torsion bar spring 380 stores energy when twisted and tends to exert a force such that it returns the shaft 320 and adapter 340 to their neutral positions due to the spring force of the torsion bar spring 380.

[0025] The torsion bar spring 380 consists of a plurality of leaves 390 stacked one upon the other in a superimposed manner. Each spring leaf 390 is in the form of an elongated, rectangular strip having lateral tabs 391 extending to either side of one end of the elongated, rectangular strip to form a T-shaped head 392. When stacked, the spring leaves 390 impart a T-shape to the first end 382 of the torsion bar spring 380. The first end 382 of the torsion bar spring 380 is constrained against rotation relative to the head portion 322 of the shaft 320, and the second end 384 of the torsion bar spring 380 is constrained against rotation relative to the end piece 360.clamped so that rotation of the shaft 320 relative to the end piece 360 ​​causes the torsion bar spring 380 to twist about its longitudinal axis after the shaft 320 was initially in a neutral position.

[0026] The first end 382 of the torsion bar spring 380 is constrained from rotation relative to the head portion 322 of the shaft 320 by a cap 400. The cap 400 has a rectangular opening 401 with rounded side edges 402 and top and bottom edges 403 and 404, respectively. The cap 400 has two recesses 405 that receive the prongs 332 of the head portion 322 of the shaft 320 to securely attach the cap 320 to the head portion 322 of the shaft 320. Each recess 405 receives a corresponding one of the prongs 332. The prongs 332 are a close fit with the recesses 405. The ribs 334 of the outer surfaces of the pins help to securely attach the cap 400 to the head portion 322 of the shaft 320 by providing a tighter engagement between the inner surface of the recesses 405 and the outer surface of the pins 332.The recesses 405 and the pins 332 therefore form, in the illustrated embodiment, means for securely fastening the cap 400 to the head portion 322 of the shaft 320.

[0027] The cap 400 has a rib 406 and two axial lateral projections 407 and 408. The lateral axial projections 407 and 408 fit at least partially into the slot 330 of the head portion 322 of the shaft and close the ends of the slot 330. When the cap 400 is securely attached to the head portion 322 of the shaft 320, the rib 406 extends at least partially into the recess 316 of the hinge base 302 to limit rotation of the hinge shaft 320 relative to the hinge base 302. The rib 406 engages the end wall 319 of the recess 316 to stop rotation of the hinge shaft 320 and the adapter 340 at a position corresponding to the fully open position of the laptop lid 204. The rib 406 is in contact with the end wall 319 of the recess 316.End wall 318 of recess 316 engages to stop the rotation of hinge shaft 320 and adapter 340 at a position slightly beyond the closed position of laptop lid 204. Rib 406 and recess 316 form a safety feature to prevent overstressing of torsion bar spring 380, which could result in fracture of torsion bar spring 380.

[0028] The torsion bar spring 380 extends through the opening 401 of the cap 400. The rounded side edges 402 of the cap 400 are in direct contact with the surfaces 393 of the outermost leaves 390 of the torsion bar spring 380. The distance between the rounded side edges 402 of the opening 401 of the cap 400 is such that the fit of the torsion bar spring 380 between the rounded side edges 402 of the opening 401 is very tight or with minimal play. The rounded side edges 402 of the opening 401 are therefore responsible for transmitting torque from the shaft 320 and the torsion bar spring 380. The use of the rounded side edges 402 of the opening 401 for torque transmission between the shaft 320 and the torsion bar spring 380 arranges the torque-transmitting edges 402 in a slight offset from the T-shaped heads 392 of the spring leaves 390.This avoids the problem of stress concentration at the transition between the T-shaped heads 392 and the remaining part of the main sections in the form of the rectangular strip of spring leaves 390, which could lead to premature failure of the torsion bar spring 380. Rounding the edges 402 of the opening 401 of the cap 400 also prevents stress concentration at the edges of the outermost spring leaves 390, which could also lead to failure of the spring leaves 390 and thus also of the torsion bar spring 380. The distance between the upper edge 407 and the lower edge 408 of the opening 401 of the cap 400 is such that the T-shaped heads 392 of the leaves 390 cannot pass through the opening 401 and the T-shaped heads 392 of the leaves 390 are trapped between the cap 400 and the head portion 322 of the shaft. This arrangement limits the axial movement, iethe movement in a direction parallel to the longitudinal axis of the shaft 320 of the T-shaped heads 392 of the blades 390.

[0029] The ends 394 of the leaves 390 farthest from the T-shaped heads 392 are in a stacked state when the torsion bar spring 380 is in a relaxed state, and the ends 394 form the second end 384 of the torsion bar spring 380. The torsion bar spring 380 extends through the opening 366 of the sleeve 364. The lateral edges 370 and 372 of the sleeve opening 366 are rounded. The rounded side edges 370 and 372 of the sleeve opening 366 are in direct contact with the surfaces 393 of the outermost leaves 390 of the torsion bar spring 380. The distance between the rounded side edges 370 and 372 of the opening 366 of the sleeve 364 is such that the fit of the torsion bar spring 380 between the rounded side edges 370 and 372 of the opening 366 is very tight or with minimal play.The rounded side edges 370 and 372 of the opening 366 are therefore responsible for the transmission of torque between the end piece 360 ​​and the torsion bar spring 380. The use of the rounded side edges 370 and 372 of the opening 366 for torque transmission between the end piece 360 ​​and the torsion bar spring 380 ensures a uniform stress distribution across the width of the spring leaves 390 and prevents stress concentration at the edges of the outermost spring leaves 390. These properties increase the service life of the spring leaves 390 and reduce the risk of failure of the spring leaves 390 and accordingly also of the torsion bar spring 380. The distance between the upper edge 374 and the lower edge 376 of the opening 366 of the sleeve 364 is such that the upper edge 374 and the lower edge 376 of the opening 366 the movements of the ends 394 of the leaves 390 in the sleeve 364 do not disturb.

[0030] When the torsion bar spring 380 is twisted by any given amount about its longitudinal axis, the length of the helical path followed by the spring leaves 390 is greater for each leaf 390 that is farther from the center of the stack of leaves 390. Accordingly, the ends 394 of the hinge leaves 390 begin to retract from the back wall 366 of the sleeve 364, so that the farther a hinge leaf 390 is from the center of the stack of leaves, the more its end 394 is retracted from the back wall 368. This result is shown in the Fig. 19 and Fig. 25. Restricting this axial movement of the ends 394 of the hinge leaves 390 would result in breakage of the spring leaves. Accordingly, at least one end of each of the plurality of leaves 390 must be able to move freely axially when the torsion bar spring 380 is twisted. The ends 394 of each of the spring leaves 390 must extend far enough into the sleeve opening 366 so that, throughout the entire range of rotation of the shaft 320, there is no possibility or risk of them being completely pulled out of the sleeve opening 366.

[0031] It is possible to provide a mirror image of the sleeve 364 in the head portion 322 of the shaft instead of the cap 400. In such an arrangement, it would not be necessary for the spring leaves to have T-shaped heads. The spring leaves could simply be in the form of rectangular strips. Nor would any axial restrictions be imposed on the two ends of the torsion bar spring, except for the fact that, in the relaxed state, all the spring leaves would be enclosed between the back walls of the sleeves in the end piece 360 ​​and the sleeve at the shaft head portion 322.

[0032] When the torsion bar spring 380 is twisted, the spring ends 394 on one side of the stack's center tend to move upward or downward toward either the upper edge 374 or the lower edge 376, depending on the direction of rotation of the shaft 320, and the spring ends 394 on the other side of the stack's center tend to move in the opposite direction, but still in the same direction as the shaft's rotation. These movements must also be accommodated to avoid overloading the spring leaves 390, which could lead to leaflet failure. Therefore, as previously mentioned, the distance between the upper edge 374 and the lower edge 376 of the opening 366 of the sleeve 364 is such that the upper 374 and lower edges 376 of the opening 366 do not interfere with the movements of the ends 394 of the blades 390 within the sleeve 364.

[0033] The torsion bar cover 420 fits over the exposed portion of the torsion bar spring 380 between the end piece 360 ​​and the hinge base 302. The torsion bar cover 420 is tubular and has openings at both ends. The torsion bar cover 420 acts as a grease or lubricant reservoir and does not restrict any of the movement and flexion of the spring leaves 390, but rather ensures lubrication of the individual spring leaves. The openings 422 and 424 at the ends of the torsion bar cover 420 seal against the hinge base 302 and the end piece 360, respectively. The torsion bar cover 420 provides continuous lubrication between the spring leaves 390 to ensure that the spring leaves can slide against each other as necessary to avoid overloading and damage to the spring leaves.The torsion bar cover 420 has an alignment feature on one side in the form of a rectangular or square opening 424 to assist in the assembly process of the torsion bar spring 380. It is possible for both openings 422 and 424 to be circular or have some other shape, but large enough not to interfere with the twisting of the torsion bar spring 380.

[0034] When the hinge assembly 300 and its mirror-image hinge assembly 500 are installed in a laptop, as illustrated, the neutral position of the adapter 340 of the laptop lid 204, which corresponds to the relaxed state of the torsion bar spring 380, is between the fully open position of the laptop lid and the fully closed position of the laptop lid. In the illustrated example, the neutral position of the laptop lid is 32° from the fully open position and 85° from the closed position. The operation of the hinge assembly 300 is described starting from the initial situation in which the laptop lid is in the neutral position. To close the laptop lid 204, sufficient force must initially be applied to overcome the friction torque due to the friction mechanism 430.As the laptop lid 204 rotates toward the closed position, the hinge shaft 320 rotates, causing the torsion bar spring 380 to twist. As the torsion bar spring 380 twists, the force required to continue closing the laptop lid 204 increases due to the restoring force of the torsion bar spring 390. However, this is not a disadvantage because it is mechanically advantageous for a user to push down rather than pull up due to the effect of gravity on the lid and by applying body weight as necessary. In addition, as the torsion bar spring 380 twists, energy is stored by the deformation of the torsion bar spring 380. When the laptop lid 204 is in the closed position, a latch (not shown) secures the laptop lid 204 in the closed position.To open the laptop lid, a user actuates the latch to release the laptop lid 204 for rotation to the open position. The laptop lid 204 automatically moves from the closed position without any effort from the user, as the torque applied by the torsion bar spring 380 overcomes the frictional resistance or friction torque of the friction mechanism 430 until a point is reached, intermediate between the neutral and closed positions, where the torque applied by the torsion bar spring 380 has substantially decreased to the friction torque of the friction mechanism 430. At this point, the laptop lid 204 stops moving, and the user can conveniently manually move the laptop lid 204 to any desired position between this point and the fully open position of the laptop lid as needed.Even if there is some deformation of the torsion bar spring 380 at any position outside the neutral position, the friction torque of the friction mechanism 430 maintains the laptop screen in the desired position within the range of positions corresponding to a normal usage range of the laptop screen 206.

[0035] The material used for the spring leaves 390 is steel, such as stainless steel or spring steel, or any steel with a spring steel hardness. The shaft 320 is also made of steel. The end piece 360, the adapter 340, and the hinge base 302 can be made of a mold-cast metal, such as aluminum or zinc, or even a high-impact plastic. For lower-torque applications, the spring leaves 390 can be made of a composite material or a polymer material, as long as it has the required elasticity.

[0036] According to the Fig. 103-194, a second exemplary embodiment of the hinge assembly 600, 800 according to the present invention can be seen. Each of the hinge assemblies 600, 800 provides for a rotatable attachment of a first part to a second part to enable rotational movement of the first part relative to the second part between an open and a closed position. According to the Fig. 103-105 are two hinge assemblies 600 and 800 made in accordance with the present invention, illustrated in use for the pivotal attachment of the lid 204 of a laptop computer 200a to the base 202a of the laptop computer 200a. The laptop lid 204a typically houses the laptop screen 206a, and its angular position relative to the laptop base 202a should be adjustable within a range of angular positions suitable for people of varying sizes to properly view the laptop screen 206a.

[0037] Hinge assembly 600 is a left hinge assembly, and hinge assembly 800 is a right hinge assembly. Right hinge assembly 800 is a mirror image of hinge assembly 600 with respect to a plane perpendicular to the longitudinal axes of the shafts of each of the hinge assemblies and midway between the two hinge assemblies. Accordingly, only one hinge assembly 600 will be described in detail. Laptop lid 204a is typically releasably secured in the closed position relative to laptop base 200a by a latch of some type (not shown). The latch is operable by a user to move laptop lid 204a to the open position for rotational movement relative to laptop base 202a.

[0038] The hinge assembly 600 can be used to attach a first part to a second part such that rotational movement of the first part relative to the second part between a closed and an open position is possible. In the illustrated example, the first part is a laptop base 202a and the second part is the laptop lid 204a. The hinge assembly 600 includes an elongated shaft 620, an adapter 640, a hinge base 602, a friction mechanism 730, an end piece 660, a torsion bar spring 680, a first cap 700, and a shell or housing 677.

[0039] According to the Fig. 103-132 and 171-178, the elongated shaft 620 has at least a first end portion 626, a second portion or intermediate portion 624, and a second end portion 622. The first end portion 626 of the shaft 622 is provided with a plurality of elongated teeth 628 of triangular cross-section, which are evenly distributed around the circumference of the first end portion 626 of the shaft 620. Each of the plurality of elongated teeth 628 extends over at least most of the length of the first end portion 626 of the shaft 620. The teeth 628 are also referred to in the art as splines. In the illustrated example, the second portion or intermediate portion 624 of the shaft 620 has a larger diameter compared to the first end portion 626. The second end portion 622 of the shaft 620 is also provided with a plurality of teeth or splines 623 which are of similar shape to the teeth 628.The intermediate portion 624 of the shaft 620 has a larger diameter compared to the second end portion 622. The second end portion 622 of the shaft 620 is inserted into a bore 625 of the first cap 700 to secure the first cap 700 to the second end portion 622 of the shaft 620 such that there is no relative movement between the second end portion 622 of the shaft 620 and the first cap 700. The teeth 623 on the second end portion 622 of the shaft help to non-rotatably connect the shaft 620 to the first cap 700 by providing a stronger engagement between the inner surface of the bore 625 of the first cap 700 and the outer surface of the second end portion 622 of the shaft 620.This is because the teeth 623 provide a tighter grip between the inner surface of the bore 625 of the first cap 700 and the outer surface of the second end portion 622 of the shaft 620 when the second end portion 622 of the shaft is press-fitted into the bore 625 of the first cap 700. The bore 625 of the first cap 700 and the toothed outer surface of the second end portion 622 of the shaft 620 provide the means for securely attaching the shaft 620 to the first cap 700 and for non-rotatably connecting the shaft 620 and the first cap 700 together in the illustrated embodiment (see also FIG. Fig. 143-150).

[0040] The first cap 700 also has a front opening 630 having side edges 632 and 634, a top edge 633, and a bottom edge 635. The front opening 630 is rectangular.

[0041] The adapter 640 is attached to the shaft 620 of the first end portion 626 of the shaft 620. The adapter 640 is attached to the first end portion 626 of the shaft 620 such that the adapter 640 is restricted to rotating with the shaft 620 as a unit. The adapter 640 is designed for fixed attachment to the first part, in the illustrated example, the laptop base 202a, to move with the first part as a unit. According to the Fig. 103-135 and 136-142, the adapter 640 has a main part 642 provided with a plurality of holes 644 to enable the adapter 640 to be securely attached to the first part, for example the laptop base 202a, by screws 646.

[0042] The adapter 640 has a bore 648 provided on one side of the main body 642. The bore 648 of the adapter 640 is designed to receive the first end portion 626 of the shaft 620 in an interference fit, or tight fit, such that the shaft 620 is securely attached to the adapter 640 and the shaft 620 and the adapter 640 are non-rotatably connected to rotate together as a unit. The teeth 628 on the first end portion 626 of the shaft assist in non-rotatably connecting the shaft 620 to the adapter 640 by providing a stronger engagement between the inner surface of the bore 648 of the adapter 640 and the outer surface of the first end portion 626 of the shaft 620.The bore 648 of the adapter 640 and the toothed outer surface of the first end portion 626 of the shaft 620 provide the means for securely attaching the shaft 620 to the adapter 640 and, in the illustrated embodiment, non-rotatably connecting the shaft 620 and the adapter 640.

[0043] Many other suitable means may also be used for securely attaching the shaft 620 to the adapter 640 and the first cap 700, as well as for non-rotatably connecting the shaft 620 to the adapter 640 and the first cap 700. These include the same means listed for attaching the shaft 320 to the adapter 340. Of course, parts in which the bores 648, 625, and 348 have teeth that mate with the teeth 628, 623, and 328, respectively, are part of this list.

[0044] The hinge base 602 is designed for fixed attachment to the second part, in this example, the laptop lid 204a, to move with the second part as a unit. The hinge base 602 has at least one bearing surface 604, 606 that rotatably supports the shaft 620 such that, when the adapter 640 is attached to the first part and the hinge base 602 is attached to the second part, the first part is non-rotatably connected to the second part such that the first part can pivotally move relative to the second part between a closed position and an open position. In the illustrated example, the first and second parts are a laptop base 202a and the laptop lid 204a, respectively. The bearing surface of the hinge base 602 supports a portion of the second or intermediate portion 624 of the shaft 620 to provide pivotal support for the shaft 620 on the hinge base 602.

[0045] According to the Fig. 103-135 and 163-170, in the illustrated example, the hinge base 602 has two bearing surfaces 604 and 606. The hinge base 602 has a side 608 closest to the adapter 640 and a side 610 farthest from the adapter 640. The side 608 has an opening 612 that allows the shaft 620 to extend outward from the hinge base 602 toward the adapter 640. The side 610 has an opening 614 that allows the shaft 620 to extend out of the hinge base 602 toward the torsion bar spring 680, where it can engage the first cap 700. A stop projection 616 is provided along a portion of the edge of the opening 612. The stop projection 616 has end walls 618 and 619.The hinge base 602 has a flange 601 having a plurality of holes 603 to enable the hinge base 602 to be securely attached to the second part, for example the laptop lid 204a, by screws 605.

[0046] According to the Fig. 103-135 and 163-170, the hinge assembly 600 is provided with a friction mechanism 730 to provide frictional resistance to the rotational movement of the shaft 620 relative to the hinge base 602. In this example, the friction mechanism 730 is integrated into the material of the hinge base 602. The friction mechanism 730 is formed by at least one band 740, 742 attached to one end of the flange 601. The band 740, 742 is wrapped around at least a portion of the intermediate section 624 of the shaft 620, and the band 740, 742 terminates in a free end remote from the band's attachment point on the flange 601, thereby forming or defining a C-shaped profile for the band 740, 742. In the illustrated example, two bands 740 and 742 are provided, which are wrapped around the intermediate portion 624 of the shaft 620 in opposite directions. The bands 740 and 742 define bearing surfaces 604 and 606, respectively.The bands 740 and 742 also define the friction elements of the friction mechanism 730 by frictionally engaging the intermediate portion 624 of the shaft 620 to provide a frictional moment that acts as a resistance to relative movement between the shaft 620 and the hinge base 602. The inner radius of the C-shaped bands 740 and 742 is initially smaller than the radius of the outer surface of the second portion 624 of the shaft 620, so that each of the C-shaped bands 740 and 742 expands when wrapped around the second portion 624 of the shaft 620. The resilient restoring force of the C-shaped bands 740 and 742 causes the C-shaped bands 740 and 742 to exert a gripping force on the second portion 624 of the shaft 620.

[0047] Because the friction elements 740, 742 are connected at one end to the flange 601, the friction elements 740, 742 are prevented from rotating relative to the hinge base 602. The gripping or holding force exerted on the shaft 620 by the C-shaped bands or friction elements 740, 742 creates a frictional moment that resists rotational movement of the shaft 620 relative to the hinge base 602. The frictional moment created by the friction elements 740, 742 can be adjusted to any specified value for a particular application by changing the geometry, number, and material of the friction elements 740, 742.

[0048] The end piece 660, also referred to as the second cap, must be held in place relative to the second part, in this case, the laptop lid 204a, so that the torsion bar spring 680 provides the spring moment for the proper operation of the hinge assembly 600. In the hinge assembly 600, the end piece 660 is secured relative to the second part by being attached to the hinge base 602, which in turn is mounted to the second part, so that it is not directly mounted to the second part, as in the case of the end piece 360 ​​of the hinge assembly 300. Accordingly, once the hinge base 602 is mounted to the second part, the end piece 660 is fixed relative to the second part, so that the end piece 660 moves with the second part as a unit. The end piece 660 has two lateral projections 662 and a sleeve 664. The sleeve 664 has a front opening 667, a rear wall 668, side edges and-edges 670 and 672, an upper edge 674, and a lower edge 676. The front opening 667 is rectangular. The projections 662 of the end piece 660 engage and fit into corresponding notches 675 provided at one end of the outer shell or housing 677 to prevent relative rotation between the end piece 660 and the shell or housing 677. The housing 677, in turn, is attached to the hinge base 602 to non-rotatably fix the end piece to the hinge base 602. The housing 677 is cylindrical and houses the torsion bar spring 680. The end piece 660 is held axially in place at the end of the housing 677 remote from the hinge base 602 by a friction fit in the bore of the housing 677, by adhesives, pins or other fasteners, or any other suitable means.The housing 677 has one or more flanges 673 aligned with a portion of the hinge base flange 601. Two flanges 673 are provided in the illustrated example, located on either side of a portion of the hinge base flange 601. Each flange 673 is provided with one or more holes 678 aligned with one or more corresponding holes 681 in the hinge base flange 601 to enable the housing 677, and in turn the end piece 660, to be securely attached to the hinge base 602, for example, by the rivets 679.

[0049] According to the Fig. 103-135 and 159-162, the torsion bar spring 680 extends from the end piece 660 to the first end cap 700 on the shaft 620. The torsion bar spring 680 has a first end 682 and a second end 684. The torsion bar spring 680 is resilient and has a longitudinal axis. The first end 682 of the torsion bar spring 680 is constrained to rotate with the shaft 620 such that there is substantially no relative rotation between the shaft 620 and the first end 682 of the torsion bar spring 680 with respect to the longitudinal axis of the torsion bar spring 680.The second end 684 of the torsion bar 680 is constrained by the end piece 660 such that there is essentially no longitudinal rotation about the longitudinal axis of the torsion bar 680 between the end piece 660 and the second end 684 of the torsion bar 680, such that rotation of the shaft 620 relative to the end piece 660 causes the torsion bar 680 to twist about its longitudinal axis when the shaft 620 was initially in a neutral position. The neutral position refers to the position of each part of the hinge assembly 600 that corresponds to the relaxed state of the torsion bar 680. The torsion bar spring 680 stores energy when twisted and tends to exert a force to return the shaft 620 and adapter 640 to their neutral positions due to the lack of restoring force of the torsion bar spring 680.

[0050] The torsion bar spring 680 consists of a plurality of leaves 690 stacked one above the other. Each spring leaf 690 is in the shape of an elongated rectangular strip. The first end 682 of the torsion bar spring 680 is clamped to prevent rotation relative to the second end portion 622 of the shaft 620, and the second end 684 of the torsion bar spring 680 is clamped to prevent rotation relative to the end piece 660, so that rotation of the shaft 620 relative to the end piece 660 causes the torsion bar spring 680 to twist about its longitudinal axis when the shaft 620 was initially in a neutral position.

[0051] A shoulder 706 is provided on the shaft 620. When the hinge assembly 600 is fully assembled, the shoulder 706 is positioned to contact the stop projection 616 of the hinge base 602 to limit the rotation of the hinge shaft 620 relative to the hinge base 602. The shoulder 706 engages the end wall 619 of the stop projection 616 to stop the rotation of the hinge shaft 620 and the adapter 640 at a position corresponding to the fully open position of the laptop lid 204a. The shoulder 706 engages the end wall 618 of the stop projection 616 to stop the rotation of the hinge shaft 620 and the adapter 640 at a position slightly beyond the closed position of the laptop lid 204a.The projection 706 and the stop projection 616 form a safety device to prevent overloading of the torsion bar spring 680, which could lead to breakage of the torsion bar spring 680.

[0052] The first ends 692 of the leaves 690, which are farthest from the end piece 660, are stacked together when the torsion bar spring 680 is in a relaxed state. The first ends 692 of the leaves 690 form the first end 682 of the torsion bar spring 680. The ends 694 of the leaves 690, which are farthest from the first cap 700, are stacked together when the torsion bar spring 680 is in a relaxed state, and the second ends 694 form the second end 684 of the torsion bar spring 680. The torsion bar spring 680 extends through the opening 667 of the sleeve 664 of the end piece 660. The lateral edges 670 and 672 of the sleeve opening 667 are rounded. The rounded lateral edges 370 and 372 of the sleeve opening 667 are in direct contact with the surfaces 693 of the outermost leaves 690 of the torsion bar spring 680.The distance between the rounded lateral edges 670 and 672 of the opening 667 of the sleeve of the end piece 660 is such that the fit of the torsion bar spring 680 between the rounded edges 670 and 672 of the opening 667 is very tight or has minimal play. The rounded lateral edges 670 and 672 of the opening 667 are responsible for transmitting torque between the end piece 660 and the torsion bar spring 680. Using the rounded lateral edges 670 and 672 of the opening 667 for torque transmission between the end piece 660 and the torsion bar spring 680 provides a uniform stress distribution across the width of the spring leaves 690 and prevents stress concentration at the edges of the outermost spring leaves 690. These two results, respectively.Properties increase the service life of the spring leaves 690 and reduce the risk of failure of the spring leaves 690 and accordingly also of the torsion bar spring 680. The distance between the upper edge 674 and the lower edge 676 of the opening 667 of the sleeve of the end piece 660 is such that the upper edge 674 and the lower edge 676 of the opening 667 do not interfere with the movements of the ends 694 of the leaves 690 within the sleeve 664.

[0053] When the torsion bar spring 680 is twisted about its longitudinal axis by a given amount, the length of the helical path along which the spring leaves 690 extend is longer per degree of twist for each leaf 690, the farther it is from the center of the stack of leaves 690. Accordingly, the ends 694 of the hinge leaves 690 begin to retract from the rear wall 688 of the sleeve 664, so that the farther a hinge leaf 690 is from the center of the stack of leaves, the more its end 694 is retracted from the wall 668. This property is described in the Fig. 119-121. Restricting this axial movement of the ends 694 of the hinge leaves 690 would result in breakage of the spring leaves. Accordingly, at least one end of the plurality of leaves 690 must be able to move freely axially while the torsion bar spring 680 is being twisted. The end 694 of each of the spring leaves 690 must extend far enough into the sleeve 667 so that, throughout the entire range of rotation of the shaft 620, there is no possibility of it being completely withdrawn from the sleeve opening 667.

[0054] The opening 630 in the end cap 700 is a mirror image of the sleeve opening 667. The torsion bar spring 680 extends through the opening 630 of the first cap 700. The lateral edges 632 and 634 of the opening 630 are rounded. The rounded lateral edges 632 and 634 of the opening 630 are in direct contact with the surfaces 693 of the outermost leaves 690 of the torsion bar spring 680. The spacing between the rounded lateral edges 632 and 634 of the opening 630 of the end cap 700 is such that the fit of the torsion bar spring 680 between the rounded lateral edges 632 and 634 of the opening 630 is very tight or has minimal play. The rounded side edges 632 and 634 of the opening 630 are therefore responsible for transmitting torque between the end cap 700 and the torsion bar spring 680.The use of the rounded side edges 632 and 634 of the opening 630 for torque transmission between the end cap 700 and the torsion bar spring ensures a uniform stress distribution across the width of the spring leaves 690 and prevents stress concentration at the edges of the outermost spring leaves 690. These two facts increase the service life of the spring leaves 690 and reduce the risk of failure of the spring leaves 690 and, accordingly, of the torsion bar spring 680. The distance between the upper edge 633 and the lower edge 635 of the opening 630 of the end cap 700 is such that the upper edge 633 and the lower edge 635 of the opening 630 do not interfere with the movements of the ends 692 of the leaves 690 in the sleeve formed by the first cap 700 and the second end portion 622 of the shaft.

[0055] When the torsion bar spring 680 is twisted by a given amount about its longitudinal axis, the length of the helical path along which the spring leaves 690 extend is longer for each leaf 690, the farther the leaf 690 is from the center of the stack of leaves 690. Accordingly, the ends 692 of the hinge leaves 690 begin to retract from the second end portion 622 of the shaft, so that the farther a hinge leaf 690 is from the center of the stack of leaves, the more its end 692 is retracted from the second end portion 622 of the shaft. This fact is illustrated in the Fig.119-121. Thus, in embodiment 600, both ends of the plurality of leaves 690 are free to move axially when the torsion bar spring 680 is twisted. The end 692 of each of the spring leaves 690 must extend far enough into the opening 630 so that, throughout the entire range of rotation of the shaft 620, there is no possibility of it being completely withdrawn from the opening 630. All of the spring leaves 690 are enclosed between the rear wall of the sleeve in the end piece 660 and the sleeve formed by the first cap 700 and the second end portion 622 of the shaft.

[0056] When the torsion bar spring 680 is twisted, the leaf ends 694 on one side of the center of the stack tend to move up or down toward either the top edge 674 or the bottom edge 676, depending on the direction of rotation of the shaft 620, and the leaf ends 694 on the other side of the center of the stack tend to move in the opposite direction, but still in the same direction as the direction of rotation of the shaft 620. These movements must also be accommodated to avoid overloading the spring leaves 690, which in turn could lead to premature failure of spring leaves. Therefore, as previously mentioned, the distance between the upper edge 674 and the lower edge 676 of the opening 667 of the sleeve 664 is such that the upper edge 674 and the lower edge 676 of the opening 667 do not interfere with the movements of the ends 694 of the blades 690 in the sleeve 664.The situation is the same for the ends 692 of the spring leaves 690.

[0057] The two inner sleeves 720, 721 fit onto the section of the torsion bar spring 680 between the end piece 660 and the first cap 700 within the housing 677. The two inner sleeves 720, 721 are tubular and have openings at both ends. The two inner sleeves 720, 721 act as grease or lubricant reservoirs and do not restrict any of the movement or flexion of the spring leaves 690, but provide lubrication for the individual spring leaves. The openings 722 at one end of the inner sleeves 720, 721 seal against the first cap 700 or the end piece 660, respectively. The openings 724 of the inner sleeves 720, 721 seal against each other. The inner sleeves 720, 721 ensure continuous lubrication between the spring leaves 690 to ensure that the spring leaves can slide against each other as required to prevent overloading and damage to the spring leaves.The openings 722 at one end of the inner sleeves 720, 721 are rectangular openings to serve as a one-side alignment element to assist in the assembly process of the torsion bar spring 680. The two inner sleeves 720 and 721 also provide support for the outer housing 677.

[0058] When the hinge assembly 600 and its mirror-image hinge assembly 800 are installed in a laptop as shown, the neutral position of the hinge base 602 and the laptop lid 204a, which corresponds to the relaxed state of the torsion bar spring 680, is between the fully open position of the laptop lid and the fully closed position of the laptop lid. In the illustrated example, the neutral position of the laptop lid is 32° forward of the fully open position and 85° away from the closed position. The operation of the hinge assembly 600 will be described starting with the laptop lid initially in the neutral position. To close the laptop lid 204a, sufficient force must initially be applied to overcome the friction torque due to the friction mechanism 730.As the laptop lid 204a rotates toward the closed position, the end piece 660 is rotated, causing the torsion bar spring 680 to twist. As the torsion bar spring 680 twists, the force required to continue closing the laptop lid 204a increases due to the resilient restoring force of the torsion bar spring 680. However, this is not a disadvantage because it is mechanically advantageous for a user to push down rather than pull up due to the effect of gravity on the lid and also by applying their weight if necessary. In addition, as the torsion bar spring 680 twists, energy is stored by the deformation of the torsion bar spring 680. When the laptop lid 204a is in the closed position, a latch (not shown) secures the laptop lid 204a in the closed position.To open the laptop lid, a user actuates the latch to release the laptop lid 204a for rotation to the open position. The laptop lid 204a automatically moves from the closed position without any effort from the user, as the torque applied by the torsion bar spring 690 overcomes the frictional resistance or friction torque of the friction mechanism 730 until a point is reached between the neutral and closed positions, where the torque applied by the torsion bar spring 680 has substantially decreased to the friction torque of the friction mechanism 730. At this point, the laptop lid 204a stops moving, and the user can conveniently manually move the laptop lid 204a to any desired position between this point and the fully open position of the laptop lid as needed.Even if there is some deformation of the torsion bar spring 680 at any position outside the neutral position, the friction torque of the friction mechanism 730 maintains the laptop screen in the desired position within the range of positions corresponding to a normal usage range of the laptop screen 206a.

[0059] It is possible to interchange the friction mechanisms 730 and 430, and also to interchange the structures for the rotationally fixed connection of the torsion bar springs 680, 380 to the hinge shafts 620, 320, between the two disclosed embodiments 300 and 600. Such interchanges or permutations between the disclosed embodiments are within the scope of the invention.

[0060] The preferred material used for the spring leaves 690 is steel, such as stainless steel or spring steel, or any steel with a spring steel hardness. The hinge base 602 is preferably also made of a compliant steel. The shaft 620 is also made of steel. The end piece or second cap 660 and the adapter 640 can be made of a mold-cast metal, such as aluminum or zinc, or of an impact-resistant plastic. For lower-torque applications, the spring leaves 690 can be made of a composite material or a polymer material, as long as it has the required elasticity.

[0061] Although hinge assemblies 300 and 600 have been illustrated in the context of a laptop computer, the counterbalancing function provided by torsion bar springs 380, 680 can also be used to facilitate the use of friction hinges in heavier or heavy-duty applications where a friction moment alone would cause operating efforts to be unreasonably high or beyond the limits of normal human factors. The laminated design of the torsion bar springs allows the counterbalancing function to be achieved in a compact space and at relatively low cost. Hinge assemblies 300, 600, or similar hinge assemblies utilizing the laminated torsion bar design, could find applications in other areas where gas springs are typically used, such as toolbox lids, storage bins, luggage doors, floor hatches, and vehicle liftgates.

[0062] It is to be understood that the present invention is not limited to the embodiments described above, but includes any and all embodiments within the scope of the following claims.

Claims

[1] A hinge assembly (600) for rotatably mounting a first member (202a) to a second member (204a) to permit rotational movement of the first member relative to the second member between a closed position and an open position, the hinge assembly comprising: (a) a shaft (620) having at least a first end portion (626) and a second end portion (622), (b) an adapter (640) attached to the first end portion (626) of the shaft (620), the adapter (640) being attached to the first end portion (626) of the shaft (620) such that it is restricted to rotating with the shaft (620) as a unit, the adapter (640) being adapted for fixed attachment to the first part (202a) to move with the first part (202a) as a unit, (c) a hinge base (602) adapted for fixed attachment to the second part (204a) to move with the second part (204a) as a unit, wherein the hinge base (602) has at least one bearing surface (604, 606) which rotatably supports the shaft (620) such that when the adapter (640) is attached to the first part (202a) and the hinge base (602) is attached to the second part (204a), the first part is rotatably attached to the second part such that the first part can pivotally move relative to the second part between a closed position and an open position, (d) a friction mechanism (730) for frictionally resisting rotational movement relative to the hinge base (602), (e) an end piece (660) adapted to be held in fixed relationship relative to the hinge base (602), and (f) a torsion bar spring (680) extending between the end piece (660) and the second end portion (622) of the shaft (620), the torsion bar spring (680) having a first end (682), a second end (684), a resilient restoring force, and a longitudinal axis, the first end (682) of the torsion bar spring (680) being constrained against rotation relative to the shaft (620), the second end (684) of the torsion bar spring (680) being constrained against rotation relative to the end piece (660) about the longitudinal axis of the torsion bar spring.is clamped so that rotation of the shaft (620) relative to the end piece (660) causes the torsion bar spring (680) to twist about its longitudinal axis when the shaft was initially in a neutral position, so that the torsion bar spring (680) tends to store energy and exert a force to return the shaft (620) to its neutral position due to the restoring force of the torsion bar spring (680). (g) a housing (677) extending between the hinge base (602) and the end piece (660), the housing (677) having a bore through which the torsion bar spring (680) extends, the housing (677) being attached at one end to the hinge base (602) and at the other end to the end piece (660) to thereby ensure that the end piece (660) is held in a fixed relationship relative to the hinge base (602), wherein the friction mechanism (730) is arranged closer to the end of the housing (677) which is attached to the hinge base (602) than to the end of the housing (677) which is attached to the end piece (660), and wherein the end piece (660) has two lateral projections (662) and a sleeve (664), the projections (662) of the end piece (660) engaging and fitting into corresponding notches (675) provided at one end of the outer shell or housing (677) to prevent relative rotation between the end piece (660) and the shell or housing (677). [2] Hinge assembly according to claim 1, wherein the shaft (620) has a second portion (624) located between the first portion (626) and the second end portion (622), the second end portion (622) forming a head portion, wherein the bearing surface (604, 606) of the hinge base (602) supports a portion of the second portion (624) of the shaft (620) to provide a pivot bearing for the shaft (620) through the hinge base (602), wherein the friction mechanism (730) is supported by the hinge base (602), wherein the end piece (660) is adapted for fixed attachment to the second part (204a) so that it is held in fixed relationship relative to the hinge base (602), and wherein the torsion bar spring (680) extends from the end piece (660) to the head portion of the shaft (622) and the first end (682) of the torsion bar spring (680) is constrained to rotate with the shaft (620) as a unit. [3] Hinge assembly according to claim 2, wherein the torsion bar spring (680) consists of a plurality of stacked leaves (690). [4] The hinge assembly of claim 3, wherein at least one end of each of the plurality of leaves (690) is free to move axially when the torsion bar spring (680) is twisted. [5] Hinge assembly according to claim 1, wherein the torsion bar spring (680) consists of a plurality of stacked leaves (690). [6] The hinge assembly of claim 5, wherein at least one end of the plurality of leaves (690) is free to move axially when the torsion bar spring (680) is twisted.

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