A hinge for motor-vehicle doors, in particular for a hatchback

Abstract: Hinge for vehicle doors, in particular for articulating a hatchback to the body of a vehicle, comprising: a first and a second hinge element (12, 14) articulated to each other about a hinge axis (34) and intended to be fixed, respectively, to the vehicle and to the door, a screw (50) for fixing the first hinge element (12) to the body, the screw extending in a direction substantially orthogonal to said hinge axis (34), and an adjustment element (42) having an internal thread (48) and an external thread (46) co-axial with each other and engaging, respectively, the fixing screw (50) and a threaded hole (40) of the first hinge element (12).

Description: The present invention relates to a hinge for motor-vehicle doors, in particular for articulating a hatchback to a vehicle body. A known hinge manufactured by the same applicant comprises a first and a second hinge element, articulated to each other about a hinge axis and intended to be fixed, respectively, to the vehicle and to the door, and a screw extending in a direction orthogonal to the hinge axis, for fixing the first hinge element to the body. In hinges of this type, there is the need for adjusting the distance between the first hinge element and the body of the vehicle in a direction orthogonal to the hinge axis. This adjustment is necessary for compensating manufacturing plays of the vehicle body. In accordance with the prior art, such adjustment is carried out by inserting shims formed by thin metal plates between facing surfaces of the first hinge element and the body. This type of adjustment implies a great waste of time and does not enable particularly precise adjustments. DE-A-4034599 discloses a hinge for the rear door of a car. An installation ring is formed as an insert with a fine external thread which can be screwed into the threaded eye of the hinge shackle. Each threaded insert is provided with a hexagonal nut which surrounds the head of the fastening screw. DE-U-9310072 discloses a hinge element which is connected to a support by means of an adjustment element fixed to the hinge element and having an internal threaded hole engaged by a screw and an external thread engaged by a nut. The object of the present invention is to provide a hinge of the type indicated above, which enables the above adjustment to be carried out in simple, fast and precise manner and which has a simple structure formed by a reduced number of pieces. In accordance with the present invention, this object is achieved by a hinge having the features forming the subject of the claims. The present invention will now be disclosed in detail with reference to the attached drawings, given purely by way of non-limiting example, in which: Figure 1 is a perspective view of a hinge according to the present invention, Figure 2 is an exploded perspective view of the hinge of figure 1, Figures 3 and 4 are cross-sections taken on the line III-III of figure 1, showing the step of adjusting the hinge according to the invention. With reference to the drawings, the numeral reference 10 indicates a hinge intended to be used for articulating a hatchback to the body of a vehicle. The hinge 10 comprises a first hinge element 12 intended to be fixed to the body of the vehicle and a second hinge element 14 intended to be fixed to a hatchback. The first hinge element 12 has a base portion 16 from which two parallel lateral walls 18 project, the walls 18 having aligned holes 20. The second hinge element 14 has two parallel walls 22 provided with aligned holes 24. The walls 22 have respective flanges 26 provided with holes 28 intended to be engaged by screws (not shown) for fixing the second hinge element 14 to the hatchback. The first and the second hinge element are made of steel and are manufactured by a known method of either pressing or press-forging. A pair of bushes 30 are inserted into the aligned holes 24 of the second hinge element 14. The bushes 30 can be made of self-lubricating plastics material reinforced by a steel foil or can be made of bronze. The fact of making the bushes 30 of bronze has the advantage of establishing an electrical connection between the first and the second hinge element, which provides a connections to ground for the hatchback. An articulation pin 32 connects to each other the first and the second hinge element 12, 14 so that they are free to oscillate about a hinge axis 34. The pin 32 extends through the holes 20 of the first hinge element and through the bushes 30 carried by the second hinge element. A snap ring 36 engages an annular groove formed at one end of the pin 32. The hinge 10 can be disassembled by removing the snap ring 36 and axially removing the pin 32. On the base 16 of the first hinge element 12 there is formed a thickened portion 38 having a threaded through hole 40. The hole 40 has a left-hand fine screw thread, for instance M20 x 1 mm and may have a thickness for instance of about 10 mm. The hinge 10 comprises also an adjustment element 42 having a disk-shaped base 44 and a cylindrical portion 46. The cylindrical portion 46 has an outer left-hand screw thread which engages the internally threaded hole 40 of the first hinge element 12. The adjustment element 42 has a through hole co-axial with the cylindrical portion 46 and having a right-hand internal thread, for instance M8. A screw 50 having a thread 52 engaging the internal thread of the hole 48 is used for fixing the first hinge element 12 to the vehicle body. The screw 50 preferably has a pointed tapered end 54 and a small cylindrical section 56 with a diameter equal to the internal diameter of the threaded portion 52. With reference to figures 3 and 4, assembling of the hinge 10 on a vehicle is carried out in the following way. With reference to figure 3, the hinge 10 is assembled and the adjustment element 44 is completely screwed into the threaded hole 40. The first hinge element 22 is fixed by means of screws to the hatchback D. A known positioning equipment (not shown) holds the hatchback D in a predetermined reference position with respect to the body F. The body F has a bracket B having a hole in which there is inserted the screw 50 which fixes the second hinge element 12 to the body F. On the thread 52 of the screw 50 there is applied a paste of anti-slip material or any other material adapted to ensure that the friction coefficient between the threads 52 and 48 is greater than the friction coefficient between the threads 46 and 40. The screw 50 is then inserted into the hole formed on the bracket B of the frame F and into the hole 48. The tapered portion 54 of the screw 50 serves for simplifying centring of the hole 48. The screw 50 is screwed for instance by means of an automatic screwdriver. Initially, the adjustment element 44 is at its maximum distance h (for instance of about 4 mm) from the bracket B. Initially, the rotation of the screw in its screwing direction produces an unscrewing of the adjustment element 44 from the threaded hole 40. The unscrewing of the adjustment element 44 stops automatically when the adjustment element 44 rests against the bracket B. At this point, as shown in figure 4, the screw 50 is screwed into the hole 58 and fixes the second hinge element 12 to the bracket B. The fact that the screw 50 and the cylindrical element 46 have threads with opposite directions and the fact that the engagement between the threads 52 and 48 has a friction coefficient greater than the one existing between the threads 46 and 40 permits an automatic compensation of the mounting play of the hinge. The operator must only tighten the screw 50 and the hinge will automatically adapt itself to the dimensions of the mounting seat. The hatchback D is therefore precisely positioned with respect to the body independently of the plays of the body. In accordance with a less preferred variant of the present invention, the hinge 10 could be of a non-self-adjusting type. In accordance with this variant, the thread of the screw and the thread of the cylindrical element 46 may have the same direction. In this case, the adjustment element 42 should be rotated manually until the play h is reduced to zero and subsequently the screw 50 would be screwed into the hole 48. In this case, the base 44 of the adjustment element 42 could be provided with either flattened portions or notches indicated 60 in figure 2, for the engagement by a wrench.

Claims: Hinge for vehicle doors, in particular for articulating a hatchback to the body of a vehicle, comprising: a first and a second hinge element (12, 14) articulated to each other about a hinge axis (34) and intended to be fixed, respectively, to the vehicle and to the door, and a screw (50) for fixing the first hinge element (12) to the body, the screw extending in a direction substantially orthogonal to said hinge axis (34), characterized in that it comprises an adjustment element (42) having an internal thread (48) and an external thread (46) co-axial with each other and engaging respectively, the fixing screw (50) and a threaded hole (40) of the first hinge element (12), so that the adjustment element is axially movable with respect to the first hinge element (12). Hinge according to claim 1, characterized in that the internal thread (48) and the external thread (46) of the adjustment element (42) have opposite directions. Hinge according to claim 1, characterized in that the threaded engagement between the screw (50) and the internal thread (48) of the adjustment element (42) has a friction coefficient greater than the engagement between the external thread (46) of the adjustment element (42) and the threaded hole (40) of the hinge element (12). Hinge according to claim 1, characterized in that the fixing screw (50) has a substantially pointed tapered end (54). Hinge according to claim 1, characterized in that the internal thread (48) and the external thread (46) of the adjustment element (42) have the same direction.

Inventors: AUDISIO VITTORIO, AUDISIO, VITTORIO
Applicants: GAMMASTAMP SPA, GAMMASTAMP S.P.A.
Application year: 1999
Main classification: E05D7
IPC codes: E05D5, E05D7