JPH10273987A - Friction hinge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve durability by fixing a shaft body with a thread groove formed, to one element, fitting a pair of nuts thread-fastened to the thread groove, to the other element, and arranging an energizing means between a pair of nuts. SOLUTION: Nuts 21, 21 constrained only in relative rotation to a cover body 4 by a through hole 41 and free in axial movement through thread- fastening rotation to a shaft body 1. The nuts 21, 21 therefore move axially in the through hole 41 while being put in thread-fastening rotation according to opening/closing of the cover body. At this time, axial pressing force acts between the nuts 21, 21 due to a coil spring 22, and frictional resistance is generated to a contact face part between the thread groove of the nut 21 and the thread groove of the shaft body 1. This frictional resistance become friction torque of the cover body 4 to the shaft body 1, so that the cover body 4 is opened/closed with constant resistance. A friction hinge excellent in wear resistance and generating stable friction torque over a long period of time can therefore be realized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention belongs to the technical field of a hinge for connecting two elements in a rotating pair (a pair of elements performing only a rotational movement), and particularly to a hinge (positive friction) during rotation. Friction hinge for the purpose of causing friction).

[0002]

BACKGROUND OF THE INVENTION Generally, hinges are required to rotate smoothly with low resistance, but depending on the object to be mounted, this may be rather inconvenient. For example, in a lid opening / closing mechanism of a notebook computer in which a display is incorporated in a lid, it is necessary that the lid can be held stationary at an appropriate opening angle. Further, it is preferable that the cover on the reading surface of the copying machine, the Western style toilet seat cover, etc. be closed slowly to reduce the impact on the contact surface of the cover.

[0003]

2. Description of the Related Art As an example of a conventional hinge mechanism for this purpose, as shown in FIG. 6, a pipe-like member made of an elastic material such as rubber is provided in a bottomed cylindrical support member n having one end opened. A friction lock device m is formed by inserting an elastic member o and press-fitting a shaft p having a stepped small diameter portion into the elastic member o. This is because the elastic member o is expanded in the radial direction by press-fitting the shaft body p, and the outer circumferential surface thereof presses the inner circumferential surface q of the support member, thereby reducing the frictional resistance between the shaft body p and the elastic member o. It utilizes a torsional moment (“friction torque”) based on the torsional moment.

In order to improve this, there is a friction lock device disclosed in Japanese Utility Model Laid-Open No. 3-95482 and Japanese Utility Model Laid-Open No. 3-95483. The former friction lock device r
As shown in FIG. 7, a pressure spring s for pressing the elastic member o in the axial direction is further attached to the hinge mechanism having the above-described structure, and the pressure member s attached to the shaft body p and the elastic member o are connected to each other. This is a mechanism in which a pair of cam members t whose rotation is restrained by the pressure spring s and the support member n and whose steps are formed along the circumferential direction on opposing surfaces are interposed therebetween. this is,
Since the distance between the elastic member o and the pressure spring s changes depending on the engaged state of the rotated cam member t, the pressing force on the elastic member o changes, and the friction torque is varied. The pressing force in the state (B) is larger than the pressing force in the state (A).

As shown in FIG. 8, the latter friction lock device u fixes a plurality of disc springs v attached to a shaft with a push nut w to apply a constant pressing force to an elastic member o. , A coil spring z is connected to a connecting portion between one end x of the shaft and the supporting member n. With this configuration, in addition to the frictional force acting between the elastic member o and the support member n, the reaction force of the coil spring z that is twisted according to the rotation of the shaft body p is added to vary the friction torque.

[0006]

However, in the above-mentioned conventional friction locking device, the margin for press-fitting the shaft to the elastic member is apt to vary, so that the frictional force acting between the shaft and the holding member is divided. And the performance of the friction lock device varied.

Further, since the source of the friction torque is caused by frictional resistance generated between the elastic member made of rubber or the like and the supporting member, the secular change or fatigue deterioration due to the use environment of the elastic member or long-term repeated use. As a result, a remarkable decrease in frictional force was observed, and its durability was a problem.

Further, in order to compensate for this, an auxiliary means using a pressure spring is taken, but as long as the frictional resistance with the elastic member is caused, the above problem is not fundamentally solved. Due to the large number of parts, the reliability of the mechanism is reduced and the manufacturing cost is increased.

[0009]

Therefore, the present invention has been made in view of the above-mentioned problem, and an object of the present invention is to utilize a frictional resistance generated between a nut and a thread groove without using an elastic member as a frictional force generating source. By doing so, it is possible to provide a friction hinge that has a simple structure, is hardly affected by aging, improves durability and reliability, and can appropriately set a friction torque during rotation. Still another object of the present invention is to provide a novel friction hinge capable of changing a friction torque according to rotation of the hinge.

[0010]

To achieve the above object, a friction hinge according to the present invention is configured as follows.

According to a first aspect of the present invention, there is provided a hinge for connecting two elements in a pair of turns, wherein a shaft having a thread groove is fixed to one element and screwed into the thread groove at a predetermined interval. A pair of nuts is attached to the other element in a state where only one pair of nuts is restrained from rotating relative to the mounting portion, and the urging means for applying a pressing force in the axial direction to the nut is provided by the two nuts. It is arranged between a pair of Nantes.
The fixing of the shaft body to one element may be performed at one position at one end, or may be performed at both ends or a plurality of positions of the shaft body.

Next, in a second aspect of the present invention, a shaft having a thread groove is fixed to one element, and is fixed to another element at a different position from the element, and at a predetermined distance from the fixing portion. The screwed nut is attached to the other element while only the relative rotation with respect to the attachment portion is restrained, and further, an urging means for applying a pressing force in the axial direction to the nut is fixed to the other element. It is arranged between the part and the nut. The fixing of the shaft body to one element may be performed at one end, or at both ends or at a plurality of positions of the shaft body, as described above. Further, one end of the shaft body may be attached to one element, and the other end may be attached to the other element, and the shaft may be used as a fixed part.

Next, a third aspect of the present invention is directed to the first aspect of the present invention, wherein the screw groove formed in the shaft body is divided into two areas, and the screw grooves are formed in opposite helical directions.
A nut is screwed into each screw groove.

A remarkable effect can be obtained by making the contact surface between the thread groove of the shaft body and the thread groove of the nut, which is a component of the invention, a mirror finish.

[0015]

According to the above construction, the present invention operates as follows. A shaft fixed to one element rotates integrally with the element. On the other hand, a nut whose rotation is restricted only by the other element rotates with respect to the axis in accordance with the rotation of the element, but is not restricted by the movement in the axial direction, so that it is screwed in the axial direction. Will move. At this time, the pressing force in the axial direction is acting on the nut by the urging means, so that frictional resistance is generated on the contact surface of the meshed thread groove. This frictional resistance hinders the relative rotation between the shaft body and the nut, that is, the relative rotation at the hinges of the two elements, and acts as friction torque.

In the second aspect of the present invention, the pressing force of the urging means changes gradually due to the movement of the nut, so that the friction torque also changes. Furthermore, in the third aspect, since the helical directions of the thread grooves of the shaft are set to be opposite to each other, the nuts move in the direction of increasing or decreasing the distance by the rotation of both nuts in the same direction. As a result, the pressing force of the urging means varies.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described in detail with reference to the drawings. 1 is a partially cutaway perspective view showing the mounting state of the first embodiment, FIG. 2 is an overall cross-sectional view thereof, and FIG. 3 is an enlarged cross-sectional view of a main part. FIG. 4 is an overall sectional view showing the second embodiment, and FIG. 5 is an overall sectional view showing the third embodiment.

In each of the embodiments, components having the same function are denoted by the same reference numerals and correspond to each other to omit redundant description. In the present embodiment, as a pair of elements in a turning pair, one is a main body (for example,
The following description is based on the assumption that the other is applied to a lid (for example, a display device of a notebook computer) attached to the main body of the notebook computer.

[0019]

First Embodiment FIGS. 1 and 2 show a first embodiment, which mainly comprises a shaft body 1 and a friction rotating section 2. FIG.

The shaft body 1 is mainly made of metal, has a head 10 having an enlarged diameter at one end, and a bolt-like shape having a thread groove 11 formed at a predetermined length at the other end of a cylindrical rod shape. Is doing. While the head 10 is fixed to the mounting portion 30 of the main body 3,
The other end constitutes the friction rotating section 2 and is attached to the attaching section 40 of the corresponding lid 4.

The friction rotating portion 2 is provided with two nuts 21 having the same outer contour, and the nut 21 is separated from the thread groove 1 by a predetermined distance.
1 and a biasing means consisting of a coil spring 22 in a state where the coil spring 22 stores the expanding force by being brought into contact with both nuts 21.
The ring is provided around the shaft 1 so as not to be affected by the rotation of the shaft 1. Then, the friction rotating portion 2 is inserted and held in a cylindrical insertion opening 41 opened at a position corresponding to the lid 4. The inner cross-sectional shape of the insertion port 41 is formed in a shape compatible with the outer shape of the nut 21, and when inserting, the outer shapes of both nuts are aligned in the same direction. In this embodiment, a hexagonal nut is used as the nut 21, so that the inner space of the insertion port 41 is formed in a hexagonal column shape.

Further, the thread groove 11 of the shaft body 1 and the nut 21
The flanks 11f and 23f (surfaces connecting the crests and valleys of the screw grooves) with the screw grooves 23 are further polished as compared with ordinary bolt / nut processing, so as to have a smoother finish or a mirror finish. [Operation of Embodiment 1] With the above configuration, the nuts 21 (the same outer shape) inserted and held in the insertion port 41 are restricted only by the insertion port 41 in relative rotation with respect to the lid 4. Can be freely moved in the axial direction by screwing rotation with respect to.
For this reason, according to the opening and closing of the lid 4 (arrow a), the shaft 1
The nuts 21 and 21 screwed together move in the insertion hole 41 in the same direction along the axis while being screwed and rotated together (arrow b or arrow c). At this time, both nuts 21,
Since a pressing force for pressing in the axial direction acts between the nuts 21 by the expanding force of the coil spring 22, the nut 21
A frictional resistance is generated at the contact surface between the screw groove 23 of the shaft member 1 and the screw groove 23 of the shaft body 1. This frictional resistance becomes the friction torque of the lid 4 that restrains the rotation of the nut 21 with respect to the shaft 1, and the lid 4 opens and closes with a certain resistance (arrow a).

Further, by appropriately adjusting the distance between the nuts 21 and 21 in advance and attaching the nuts 21 to the insertion holes 41, it is possible to change the pressing force due to the expansion force of the coil spring 22 and set an appropriate friction torque. It becomes possible.

Further, when the flanks 11f and 23f are made smoother and mirror-finished, the frictional resistance per unit contact surface is reduced. The friction torque according to the above configuration correlates with the total area obtained by multiplying the contact area on the flank per pitch by the number of pitches. Therefore, by increasing the number of contacting pitches, the wear resistance can be improved without reducing the friction torque. In this embodiment, the friction torque is 8 kg with a bolt having a diameter of 8 mm.
Adjust the coil spring to obtain fcm
An opening / closing test was performed 100,000 times, in which the rotation was repeated once, and the friction torque was not changed.

[0025]

Second Embodiment Next, FIG. 4 shows a second embodiment.
Two nuts 21 and 2 of the friction rotation unit 2 in the first embodiment
1, a portion of the nut 21 on the tip end portion of the shaft body is fixed to the shaft body 1 side, and a fixing portion 24 not restricted by the rotation of the lid body 4 side.
Is replaced by Further, a plurality of disc springs 25, 25,... Laminated back to back are used as the urging means. The other components are the same as those in the first embodiment, and thus the same reference numerals are given and the description is omitted. [Operation of the Second Embodiment] With the above configuration, the nut 2 is opened and closed (arrow a) as in the first embodiment.
1 is screwed and rotated and moves in the insertion hole 41 along the axial direction (arrow d or arrow e). That is, depending on the direction of the spiral of the screw groove 11, for example, the nut 21
Moves in the direction of arrow d in the closing step.

When the nut 21 moves in the direction of arrow d, the distance between the fixing portion 24 and the nut 21 increases, so that the pressing force of the disc spring 25 on the nut 21 gradually decreases, and the friction torque also gradually decreases. I will go. Conversely, when moving in the direction of the arrow e, the distance between the fixing portion 24 and the nut 21 is reduced, and the friction torque is gradually increased.

As described above, the configuration of the second embodiment differs from the first embodiment in which a constant friction torque is generated, in that the friction torque varies according to the opening angle of the lid 4. When such a mechanism is used, for example, as a hinge of the lid 4 that closes horizontally, it can be prevented from being suddenly closed due to the addition of gravity, and can exhibit a so-called damper-like function.

[0028]

Third Embodiment FIG. 5 shows a third embodiment. Note that the same components as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted.

The shaft body 5 is different from the bolt-shaped embodiment 1 in that
It has a rod shape, and the formation area of the screw groove 50 is divided into two sections, and the screw grooves 50a and 50b in the opposite helical directions are formed respectively. One nut 21 is screwed into each of the thread grooves 50a and 50b of each section, and the configuration of the friction rotation unit 2 is such that the coil spring 22 is extended between the nuts 21 and 21 in the same manner as the configuration of the first embodiment. Is interposed.

The thread grooves 50a and 50b are formed up to both ends in consideration of the screwing of the nuts 21 and 21, so that the shaft body 5 is attached to the main body 3 at one end. A fixed portion is formed by a double nut 51 in the portion, and is fixed to the mounting portion 30. [Operation of Embodiment 3] With the above configuration, similarly to Embodiments 1 and 2, the nut 21 is screwed and rotated in the axial direction along the axial direction according to the opening and closing of the lid 4 (arrow a). Move (arrow f or arrow g). At this time, both nuts 21, 2
Although 1 rotates in the same direction, since the spiral directions of the screw grooves 50a and 50b are two sections (left and right in the drawing) and are opposite directions, they move in opposite directions. as a result,
Depending on the set spiral direction of the thread groove 50, for example, when the nut 4 is moved in a direction (arrow f) in which the interval between the two nuts 21 widens in the opening process of the lid 4, the nut 21
The pressing force gradually decreases, and the friction torque also gradually decreases. Conversely, in this closing step, the direction in which the interval between the two nuts 21 is reduced (arrow g)
, The friction torque gradually increases.

[0031]

[Possibility of Other Embodiments] In the above embodiment, the friction rotating portion 2 of the shaft 1 (or 5) is arranged on the side of the lid 4 where the display device of the notebook computer is located. Needless to say, it may be attached to the main body 3 side.

In the above embodiment, the mechanism of the friction rotating portion 2 disposed on the shaft 1 (or 5) is one set, but a plurality of sets of the mechanism are connected in series to one shaft 1 (or 5). It is also possible to attach it.

In the first and third embodiments, the coil spring 22 is used as the urging means. However, the present invention is not limited to this, and the inner wall of the insertion port 41 such as the laminated disc spring 25 as shown in the conventional example is used. As long as it has a pressing force for expanding the space between the nuts without touching the nut, it includes all biasing means conceivable in the state of the art.

An urging means for changing the pitch of the thread groove of the shaft and the nut in accordance with a desired rate of change of the friction torque, and changing the urging force in accordance with the contraction distance;
For example, an unequal pitch coil spring or the like may be used.

[0035]

According to the above-described structure, the present invention, notwithstanding the simple structure, does not use the contact friction force with an elastic member such as rubber but mainly uses the contact friction force between metals. Therefore, a friction hinge that is excellent in wear resistance and generates a stable friction torque for a long period of time can be realized, and its industrial effect is remarkable.

According to the first aspect of the invention, the friction torque can be appropriately set by appropriately setting the interval between the nuts before the hinge is mounted, and a constant friction torque can be set in the opening and closing process. Can be generated. By increasing the torque, it is possible to hold the vehicle still at a desired opening angle.

According to the second and third aspects of the present invention, a gradually changing variable friction torque can be generated in the opening and closing process. As a result, different friction torques can be set at the beginning and end of opening and closing, and the applicable device can be made to perform a moderate opening and closing operation.

Further, according to the structure of claim 4, since the frictional resistance per unit contact area is reduced, the abrasion resistance is increased, and the durability and reliability of the hinge can be further improved. .

[Brief description of the drawings]

FIG. 1 is a perspective view showing a mounting state of a first embodiment with a part cut away.

FIG. 2 is an overall sectional view of the first embodiment.

FIG. 3 is an enlarged cross-sectional view of a main part of the first embodiment.

FIG. 4 is an overall sectional view showing a second embodiment.

FIG. 5 is an overall sectional view showing a third embodiment.

FIG. 6 is an overall sectional view showing a conventional example.

FIG. 7 is an overall sectional view showing a conventional example.

FIG. 8 is an overall sectional view showing a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Shaft 11 Screw groove 2 Friction rotation part 21 Nut 22 Coil spring 24 Fixed part (~ of Example 2) 25 Disc spring 3 Main body 30 Mounting part (~ of body) 4 Lid 40 Mounting part (~ of lid) 41 Insertion port 5 Shaft (from the third embodiment) 50a, 50b Screw groove (from the third embodiment) 51 Double nut

Claims (4)

[Claims] 1. A hinge for connecting two elements in a circling pair, wherein a shaft having a thread groove is fixed to one element, and a pair of nuts screwed into the thread groove at a predetermined interval. In a state where only the relative rotation to the mounting part is restrained,
A friction is characterized in that a pair or a plurality of pairs are attached to the other element, and biasing means for applying a pressing force in the axial direction to the nut is arranged between the two pairs of the nants. Hinges. 2. A hinge for connecting two elements in a circling pair, wherein a shaft formed with a thread groove is fixed to one element, and is fixed to another element at a different position from the other. A nut screwed to the part at a predetermined interval, attached to the other element while restricting only relative rotation with respect to the mounting part, and further, urging means for applying a pressing force in the axial direction to the nut, A friction hinge, wherein the friction hinge is disposed between a fixing portion and a nut. 3. A formation area of a thread groove formed in a shaft body is divided into two sections, and a thread groove in an opposite helical direction is formed, respectively.
2. The friction hinge according to claim 1, wherein a nut is screwed into each thread groove. 4. The friction hinge according to claim 1, wherein the contact surface between the thread groove of the shaft body and the thread groove of the nut is mirror-finished.