EP1961898A1

EP1961898A1 - Hinge mechanism for cargo compartments of buses and improvements thereof

Info

Publication number: EP1961898A1
Application number: EP07102709A
Authority: EP
Inventors: Levent Erkocak; Hakan Cemil Ipekci
Original assignee: Makersan Makina Otomotiv Sanayi Ticaret AS
Current assignee: Makersan Makina Otomotiv Sanayi Ticaret AS
Priority date: 2007-02-20
Filing date: 2007-02-20
Publication date: 2008-08-27

Abstract

The present invention proposes an improved hinge mechanism design allowing operability of a cargo compartment door in the manner that the latter rotates around an axis outside the compartment space so as to reach a substantial degree of openness. A set of arms in the form of a J-profile arm and a crescent-like profile arm hinged to a first corner piece secured to the upper part of the compartment. The second corner piece secured from the inside to the upper part of the door is fastened to an L-profile arm connected to said J-profile arm and to a linear arm connected to said crescent-like profile arm. The hinging arms provide a parabolic movement that initially pushes the door downward and then rotates it around an axis set at a certain distance from the outermost plane of the compartment space.

Description

Technical Field of the Invention

The present invention relates to a hinge mechanism for a luggage compartment of a bus.

Background of the Invention

As is known, the luggage compartments are located on the underside of side-windows of buses. The present technical field discloses several applications to enable safe and sound operation of hinged cargo cell doors. Bus luggage compartments are generally equipped with rotatably opening doors, the hinges of which provide rotation around an axis along the upper edge of the compartment door. The door is secured to two separate hinges at both sides of each compartment.
There are quite a number of factors determining operability of a hinged luggage compartment door, among others those such as the direction of the rotation axis, the weight of the compartment door to be carried by the mechanism, operability of damper mechanisms in connection with the hinge mechanism and maximum opening angle between the plane of a first corner piece secured to an appropriate location within the compartment and the plane of a second corner piece to which the door itself is secured, are especially decisive. The direction of the rotation axis is critical in that it determines the volume swept by the door when in fully opened position up to the natural limit of side-windows above the compartment, that is to say the maximum degree of openness a door can reach. Therefore direction of the rotation axis is of importance for the sake of usability.
Another constraining factor in designing hinges of the present type lies in the fact that the peripheral profile at the outermost part of the compartment space in the manner to extend all along the edges thereof and to protrude therefrom on the outermost plane of the compartment space, stands as a restricting barrier against the functioning of the hinge mechanism due to the necessity to position the latter as close to the door as possible for mechanical reasons. The presence of the outer edge profile in luggage compartments due to mechanical and constructional reasons is a factor that manufacturers and designers of hinges of the present type must take into account. An alternative design accommodating the door hinging mechanism deeper in the cargo division would require use of higher amount of material along with a substantially different design to be able to carry the axis of rotation outside the division and to overcome problems due to increased moment arm.
Examples of prior art applications in the field, such as those widely available in the market of the applicant's country, accommodate two corner pieces to which the compartment door and the hinge mechanisms are secured, to which are also fastened hinge arms in the form of S-profile and I-profile arms. In this configuration, two I-profile arms are fastened both to each other and to the corner pieces. The third I-profile arm is fastened to said S-profile arm and the two extremities of said I-profileS-profile device is fastened to the two corner pieces.
A luggage compartment hinge of the above type incorporates several drawbacks especially in that the rotation axis of the compartment door extends along the upper border of the door, i.e. adjacent to the corner piece to which the mechanism is secured. The outcome of this abreast design leads to a limited degree of openness for the luggage door. Moreover, the edge profile of the division stands just in between the axis of rotation and the inner corner piece to which the hinge mechanism is fastened. It is therefore a necessity that the hinged arms carry and rotate the compartment door in a manner to jump it over said edge profile, which is clearly further restricting rotating capability of the hinge.
The hinge mechanism according to the present invention ensures that the rotational movement of the door takes place outside the volume defined by the cargo compartment in the manner that peripheral profile at the outermost part of the compartment space does not stand as a restricting barrier against the functioning of the hinge mechanism. The hinging arms hereof are designed to provide a parabolic movement that initially pushes the door downward and then rotates it around an axis set at a certain distance from the outermost plane of the compartment space. A rotation axis outside the division let the door sweep a greater arc portion.
The hinge mechanism according to the present invention is suitably connected to compartment door dampers. To design the point to which the shock absorbers are to be fastened is of great importance since the uppermost and the lowermost limit length of operation thereof vary according to the displacement of the connection point during operation. In the event that the connection point is not appropriately adjusted, a shock absorber with a shorter distance between its upper and lower limits will not work properly. The hinge mechanism according to the present invention is also suitable for operating along with absorbers whose strokes, i.e. difference between fully extended and fully compressed position, are shorter.

Objects of the Invention

The primary object of the present invention is to provide a hinge mechanism especially for luggage compartment doors of buses, enabling the door to expose an improved sweeping angle around the hinge and therefore enhancing usability of the door mechanism.
Another object of the present invention is to provide a hinge mechanism ensuring that the rotational movement of the door around the hinge mechanism takes place outside the volume defined by the cargo compartment, which is also advantageous in regard to both operation and manufacturing simplicity.
Another object of the present invention is to provide a hinge mechanism that can advantageously be connected to a damper in the manner that the damper operates safely in between its uppermost and lowermost limit lengths.

Summary of the Invention

The present invention proposes an improved hinge mechanism design allowing operability of a cargo compartment door in the manner that the latter rotates around an axis outside the compartment space so as to reach a substantial degree of openness. A set of arms in the form of a J-profile arm and a crescent-like profile arm are hinged to a first corner piece secured to the upper part of the compartment. A second corner piece secured from the inside to the upper part of the door is fastened to an L-profile arm and to a linear arm, both connected to said crescent-like profile arm. The hinging arms provide a parabolic movement that initially pushes the door downward and then rotates it around an axis set at a certain distance from the outermost plane of the compartment space.

Brief Description of the Figures

Accompanying drawings are given solely for the purpose of exemplifying a luggage compartment hinge mechanism whose advantages over prior art were outlined above and will be explained in detail hereinafter:

Fig. 1 demonstrates an upper view of a prior art hinge mechanism for luggage compartments.
Fig. 2 demonstrates an upper view of the hinge mechanism for luggage compartments according to the present invention.
Fig. 3.a to Fig. 3.l demonstrates 12 different positions of each part of the hinge mechanism and displacement thereof during advancement from fully closed to fully opened position.
Fig. 4 demonstrates the parabolic trajectory on which the second corner piece advances during opening.
Fig. 5 demonstrates the hinge mechanism according to the present invention in closed position with the parallelogram ABCD.
Fig. 6 demonstrates a prior art hinge mechanism in fully opened position.
Fig. 7 demonstrates the hinge mechanism detail of Fig. 6.
Fig. 8 demonstrates the hinge mechanism according to the present invention in fully opened position.
Fig. 9 demonstrates the hinge mechanism detail of Fig. 8.

Detailed Description of the Invention

Referring now to the figures outlined above, the hinge mechanism (11) according to the present invention features a first corner plate (12) to which two separate arms are fastened. Those are the J-profile main drive arm (24) and the crescent-like profile secondary drive arm (21), the latter with a shorter moment arm. The J-profile main drive arm (24) is further connected to an L-profile transmission arm (22), which transmits motion to a second corner piece (13). The crescent-like profile secondary drive arm (21) also drives a second transmission arm (23) joined to said second corner piece (13). While two pivotable joints (14, 15) on the first corner piece (12) connect respectively the J-profile main drive arm (24) and the crescent-like profile secondary drive arm (21) to said first corner piece (12), two pivotable joints (16, 20) on the second corner piece (13) connect respectively said L-profile transmission arm (22) and said linear transmission arm (23) to said second corner piece (13). Further, while an intermediary joint (25), pivotable around a common rotation axis of said crescent-like profile secondary drive arm (21) and said L-profile transmission arm (22) connect those two at a point on the horizontal line of said joint 20 in fully closed layout, a pivotable joint (18) connects said J-profile main drive arm (24) and said L-profile transmission arm (22) and another pivotable joint (19) connects said crescent-like profile secondary drive arm (21) and said linear transmission arm (23).
Having referred to the principal parts, the main characteristics of the present invention lie in the manner the driver arms move and determine the direction the door surface takes prior to rotational movement. The allowed amount of displacement of every individual driver arm (24, 21) with respect to the position of the pivotable joints (18, 19) along with synchronous rotation of the common coaxial joint (25) provides said second corner piece (13) with a parabolic trajectory, that is to say a trajectory that enables an initially downwardly sliding opening sequence so as to allow the door rotate around an axis outside the luggage division, therefore enhancing the degree of angle the door can sweep up to its fully opened position.
The shape the hinge mechanism takes during 12 different instants of the opening sequence is shown in Figures 3.a to 3.l. Since the first corner piece (12) is secured to the upper part of the luggage compartment, the initial movement of the second corner piece (13) will progress at the very beginning according to a set of displacements by the transmission arms (22, 23). The amount of rotation of the joints 14, 15, 18, 19 and 25 at the beginning of the opening sequence is determined by the two transmission arms (22, 23) and more precisely by the distance in between said pivotable joints 25 and 16 at one hand and 19 and 20 at the other hand. Due to the fact that those distances are substantially similar to each other and that the line segments formed by those two groups of joints (25-16 and 19-20) are substantially parallel to each other, the only possible destination for the second corner piece (13) is downwards. In other words, rotation of the second corner piece (13) merely around its upper joint (16) to reach an opened door position is not possible since both of its joints (16, 20) are driven by substantially equal length arms/arm portions at the ends of which substantially equally spaced joint groups (16-20 and 19-25) are present. Arms/arm portions referred to herein are the outer portion of the L-profile transmission arm (22) -the arm portion in between said pivotable joints 25 and 16- and the linear transmission arm (23). The layout of the pivotable joints 16, 20, 19 and 25 in closed position thus forms a substantially regular parallelogram. The parallelogram ABCD is seen in Fig. 5.
It can be seen from Fig. 3 that deformation of the opposite parallel sides BC and AD in the parallelogram ABCD is not substantially noticed from Fig. 3.a to Fig. 3.d. In these figures, while the corner points A and C approach to each other, the distance between the corner points B and D grows. The fact that the distance AD is slightly smaller than the distance BC and further that the lower joint 19 on the crescent-like profile secondary drive arm (21) moves outward faster than does the intermediary joint (25), results in that for a given amount of rotation of said joint 14, a greater amount of rotation is induced in joint 19 compared to that of joint 25, thus increasing the distance BD and decreasing the distance AC.
The position of the crescent-like profile secondary drive arm (21) in Fig. 3.e, that is to say the point C being in an outer position relative to that of point D due to both the length difference between AD and BC and faster displacement of the lowermost end of the crescent-like profile secondary drive arm (21) around the rotation axis of the joint 15, requires that the secondary corner piece (13) rotate around the pivotable joint 16. The opening sequence as from Fig. 3.e to the fully closed position in Fig. 3.l demonstrates displacement of the secondary corner piece (13) so as to reach as much as 264 degrees of openness.
Said pivotable crossing joint (25) according to the present invention, is preferably positioned in the middle of two curved side portions of said crescent-like profile driving arm (21). A positioning of said pivotable crossing joint (25) at a point other than between the two curves of said crescent-like profile driving arm (21) would change the length proportion between the line segments from said pivotable crossing joint (25) to the pivotable joint 16 and from the pivotable joint 19 to the pivotable joint 20. This would also spoil the parallelism between the line segments AD and BC.
According to the present invention, said J-profile arm (24) is designed to be curved along its upper portion. The curvature of said J-profile arm (24) functions in the manner to prevent further rotation around said pivotable joint 14 in fully opened position. It can be seen from Fig. 3.l that said curvature, when said J-profile arm (24) is rotated around the pivotable joint 14, leans against said corner piece (12) at its curved surface.
According to the present invention, the shock absorbers are fastened through a connection point 17 in a position toward a back part of said crescent-like profile driving arm (21), which is on the horizontal line of said common joint 25 in fully closed layout. The functioning of a shock absorber is known to a man skilled in the art. Those simply operate in the manner to resist against movement of the compartment door so as to soften opening and closing movement thereof. The amount of displacement of said connection point 17 on said crescent-like profile driving arm (21) during opening allows short stroke shock absorbers to operate safely.
It can be seen from Fig. 7 that a prior art hinge mechanism prove difficult to be mounted appropriately in order for operating without cutting the compartment edge profile. In Fig. 7, it is seen that the compartment profile should be partly cut to accommodate the upper corner piece. Fig. 9 shows positioning of a hinge mechanism according to the present invention relative to said edge profile.
The present invention in a nutshell proposes a hinge mechanism especially for driving a luggage compartment door of a bus which comprises a first and a second corner piece (12, 13) secured respectively to an upper part of the compartment and to the door to be rotated, a first driving arm (24) and a second crescent-like profile driving arm (21), each being pivotally connected respectively to a first transmission arm (22) and to a second linear transmission arm (23) by means of joints (18, 19), the latter arms (22, 23) being directly connected to said second corner piece (13) at two pivotable joints (16, 20) and said crescent-like profile second driving arm (21) being pivotally connected to said first non-linear transmission arm (22) from a pivotable crossing joint (25). The length of the line segment from said pivotable crossing joint (25) to the pivotable joint 16 is substantially equal to the length of said second transmission arm (23) and the line segments formed in closed position by said pivotable joints 25 and 19 at one hand and 16 and 20 at the other hand are substantially parallel to each other.

Claims

A hinge mechanism especially for driving a luggage compartment door of a bus comprising a first and a second corner piece (12, 13) secured respectively to an upper part of the compartment and to the door to be rotated, a first driving arm (24) and a second driving arm (21), each being pivotally connected at their end portions respectively to a first transmission arm (22) and to a second transmission arm (23) by means of joints (18, 19), the latter arms (22, 23) being directly connected to said second corner piece (13) at two pivotable joints (16, 20) and said second driving arm (21) being pivotally connected to said first transmission arm (22) from a pivotable crossing joint (25) characterized in that;
the length of the line segment from said pivotable crossing joint (25) to the pivotable joint 16 is substantially equal to the length of said second transmission arm (23) and,
the line segments formed in closed position by said pivotable joints 25 and 19 at one hand and 16 and 20 at the other hand are substantially parallel to each other,
whereby said second corner piece (13) moves downward at the very beginning of the opening sequence.
A hinge mechanism as set forth in Claim 1 wherein the length of the line segment from said pivotable crossing joint (25) to the pivotable joint 16 is slightly smaller than the length of said second transmission arm (23).
A hinge mechanism as set forth in Claim 1 wherein said second driving arm (21) is shaped to expose two curved side portions between which an outward protrusion extends to accommodate said pivotable crossing joint (25).
A hinge mechanism as set forth in Claim 1 wherein said intermediary joint (25), pivotable around a common rotation axis of said secondary drive arm (21) and said first transmission arm (22), connect these two arms at a point on the horizontal line of said joint 20 in fully closed layout.
A hinge mechanism as set forth in Claim 1 wherein the layout of the pivotable joints 16, 20, 19 and 25 in closed position forms a substantially regular parallelogram.
A hinge mechanism as set forth in Claim 1 wherein said pivotable joint 14 is at an upper position relative to the horizontal line on which said pivotable joint 15 is located.
A hinge mechanism as set forth in Claim 1 wherein a shock absorber is fastened at a position toward the back of second driving arm (21), which is on the horizontal line of said common joint 25.
A hinge mechanism as set forth in Claim 1 wherein the length of the line segment between said pivotable joints 18 and 25 is smaller than the line segment between the pivotable joints 25 and 16.
A hinge mechanism as set forth in Claim 1 wherein said J-profile arm (24) is provided with a curvature such that further rotation around said pivotable joint 14 is prevented in fully opened position when said curvature leans against said corner piece 12.
A hinge mechanism as set forth in Claim 1 wherein said J-profile drive arm (24) is longer than said linear transmission arm (23).