Multi-axis hinge device and electronic device using the same

Abstract

To perform proper correction of a surface length difference to a flexible display sheet in all states including an inner folded state, a deployment state, and an outer folded state.SOLUTION: A multi-axis hinge device is used in an electronic device formed by attaching a flexible display sheet in a manner that the flexible display sheet spans both surfaces of a pair of housings and connects the pair of housings in an openable and closable manner. The multi-axis hinge device has: a base frame sandwiched between the pair of housings and supporting each of the pair of housings in a swingable manner; and a housing slide mechanism configured to provide a separation movement distance for separating the pair of housings from the base frame according to swing angles of the pair of housings. The housing slide mechanism changes the separation movement distance according to swing areas of the pair of housings.SELECTED DRAWING: Figure 5

Description

[Technical field] 【0001】 The present invention relates to a multi-axis hinge device that is suitable for use in various electronic devices such as mobile phones, electronic organizers, PDAs, netbooks, and even notebook computers, and that is configured by attaching a flexible display sheet, for example made of organic electroluminescence, across both surfaces of a pair of housings, and also to an electronic device that uses this multi-axis hinge device. [Background technology] 【0002】 In recent years, electronic devices such as mobile phones that have a single flexible organic electroluminescence (EL) display sheet attached across both surfaces of a pair of housings have been developed and are becoming available. The following Patent Document 1 discloses a structure that reduces problems caused by differences in surface length, such as slackness or tension in the flexible display sheet, when such electronic devices are moved from a folded state to an unfolded state. [Prior art documents] [Patent documents] 【0003】 [Patent Document 1] JP 2023-009923 A Summary of the Invention [Problem to be solved by the invention] 【0004】 In the prior art documents, measures are taken to deal with the difference in surface length of the flexible display sheet according to the unfolding angle in the process of transitioning the electronic device from a folded state to an unfolded state. However, it is not possible to take appropriate measures to deal with the difference in surface length of the flexible display sheet in all three states of the electronic device, which are the inwardly folded state, the unfolded state, and the outwardly folded state. Therefore, an object of the present invention is to provide a structure capable of taking appropriate measures to address the difference in face length of a flexible display sheet in all states, including the inward folded state, the unfolded state, and the outward folded state. [Means for solving the problem] 【0005】 In order to solve the above problem, the invention described in claim 1 is a multi-axis hinge device that is used in an electronic device having a pair of housings with a flexible display sheet attached across both surfaces of the pair of housings and connects the pair of housings in an openable and closable manner, the multi-axis hinge device having a base frame that is sandwiched between the pair of housings and supports each of the pair of housings so that the pair of housings can swing, and a housing slide mechanism that provides a separation movement amount that separates the pair of housings from the base frame depending on the swing angle of the pair of housings, and the housing slide mechanism changes the separation movement amount depending on the swing range of the pair of housings. 【0006】 Next, the invention described in claim 2 is characterized in that the housing slide mechanism changes the amount of separation movement in an area where the flexible display sheet transitions from an outwardly folded state to an unfolded state and in an area where the flexible display sheet transitions from an unfolded state to an inwardly folded state. 【0007】 Next, the invention described in claim 3 is characterized in that the housing slide mechanism makes the amount of separation movement in the area where the flexible display sheet transitions from an outward folded state to an unfolded state smaller than the amount of separation movement in the area where the flexible display sheet transitions from an unfolded state to an inward folded state. 【0008】 Next, the invention described in claim 4 is characterized in that the housing sliding mechanism includes a holding part provided on the base frame, a sliding arm that swings according to a swing angle between the holding part and the pair of housings, a sliding conversion part that converts the swing angle of the sliding arm to the separation movement amount, and a tension bracket that imparts the separation movement amount of the sliding conversion part to the pair of housings, and the sliding conversion part changes the separation movement amount according to a swing range of the sliding arm. 【0009】 Next, the invention described in claim 5 is characterized in that the slide conversion portion has a cam portion that sets the swing angle of the slide arm as the axial movement amount in the swing axis direction of the slide arm, and the cam inclination amount of the cam portion changes depending on the swing range of the slide arm. 【0010】 Next, the invention described in claim 6 is characterized in that the slide conversion part has an axially moving plate that is swingably supported by the slide arm and a first joint and moves axially in response to the axial movement of the slide arm, and a conversion plate that converts the movement direction of the axially moving plate into the direction of the separation movement amount, and the conversion plate is connected to the tension bracket. 【0011】 Next, the invention described in claim 7 is characterized in that the conversion plate amplifies the amount of movement of the axially moving plate to become the amount of movement of the tension bracket. 【0012】 Next, the invention described in claim 8 is characterized in that the multi-axis hinge device described in any one of claims 1 to 7 is used in an electronic device. Effect of the Invention 【0013】 When configured as in claim 1, it is possible to reduce slack and tension that occurs in the flexible display sheet when it is folded. 【0014】 When configured as in claim 2, it is possible to reduce slack and tension that occurs in the flexible display sheet when it is folded. 【0015】 When configured as in claim 3, it is possible to reduce slack and tension that occurs in the flexible display sheet when it is folded. 【0016】 When configured as in claim 4, it is possible to reduce slack and tension that occurs in the flexible display sheet when it is folded, with a small number of parts. 【0017】 When configured as in claim 5, it is possible to reduce the slack and tension that occurs in the flexible display sheet when it is folded while achieving compactness. 【0018】 When configured as in claim 6, it is possible to reduce the slack and tension that occurs in the flexible display sheet when it is folded while achieving a compact size. 【0019】 When configured as in claim 7, it is possible to reduce slack and tension that occurs in the flexible display sheet when it is folded. 【0020】 When configured as in claim 8, it is possible to reduce slack and tension that occurs in the flexible display sheet when the electronic device is folded. [Brief description of the drawings] 【0021】 [Figure 1] 1A and 1B show an electronic device having a flexible display sheet using a multi-axis hinge device according to the present invention, in which (a) is an oblique view of the housing when the flexible display sheet is in an inwardly folded state, (b) is an oblique view of the housing when the flexible display sheet is in an unfolded state, and (c) is an oblique view of the housing when the flexible display sheet is in an outwardly folded state. [Diagram 2] 1 is a plan view showing the arrangement of a pair of housings and a multi-axis hinge device when the flexible display sheet is in an unfolded state. FIG. [Diagram 3] FIG. 2 is a perspective view of the mounting plate, the base frame, the cover, and the lower cover. [Figure 4] 1A and 1B are diagrams illustrating the difference in face length, where (a) is a schematic diagram showing the state change of a flexible display sheet, and (b) is a diagram showing an example of the change in face length difference when transitioning from an outwardly folded state to an unfolded state to an inwardly folded state. [Diagram 5] 1A and 1B are diagrams showing an overall image of a housing sliding mechanism, in which (a) is a perspective view of the housing sliding mechanism when placed on a mounting plate, and (b) is a plan view of the housing sliding mechanism when placed on a mounting plate. [Figure 6] 1A and 1B are plan views explaining the operation of the axial moving plate and the conversion plate, which are part of the slide conversion part in the housing slide mechanism, where (a) is a diagram omitting the axial moving plate and the upper cover for the sake of explanation, and (b) is an operation diagram adding the axial moving plate and the upper cover. [Figure 7] 1A and 1B are perspective views of a holding portion, a slide arm, and a cam portion and an elastic portion which are part of a slide conversion portion in a housing slide mechanism, where FIG. [Figure 8] 13 is an exploded perspective view of a holding portion, a slide arm, and a cam portion and an elastic portion which are part of a slide conversion portion in the housing slide mechanism, as viewed from the rear side. FIG. [Figure 9] 1A and 1B are perspective views explaining the operation of the slide arm in the housing slide mechanism, where (a) is a perspective view when the flexible display sheet is in an inward folded state, (b) is a perspective view when the flexible display sheet is in an unfolded state, and (c) is a perspective view when the flexible display sheet is in an outward folded state. [Figure 10] 1A is a perspective view of a slide arm and an action cam which is part of a slide conversion part, and a coil spring which is an elastic part, and FIG. 1B is an enlarged perspective view of the action cam. [Figure 11] 1A and 1B are diagrams explaining the synchronization of the slide arm in the housing slide mechanism, where (a) is a plan view of the holding portion, the slide arm, and the action cam which is part of the slide conversion portion, and the coil spring which is the elastic portion, and (b) is a CC cross-sectional view in (a). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 【0022】 DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of a multi-axis hinge device according to the present invention and an electronic device using the multi-axis hinge device will be described in detail with reference to the accompanying drawings. EXAMPLES 【0023】 FIG. 1 shows a schematic diagram of a mobile phone A (smartphone) as an example of an electronic device using the multi-axis hinge device according to the present invention. 【0024】 FIG. 1(a) is a perspective view of a mobile phone A in which the angle between the pair of housings 1 is approximately 0 degrees and the flexible display sheet 4 is folded inward (hereinafter, referred to as the inward folded state). Here, the exterior of the mobile phone A is divided into a pair of housings 1 and a back cover 2, and the back cover 2 is composed of a pair of lower covers 21, a cover 22, a slide bracket 23, and a base bracket 24. Also, a switch 3 is provided to activate the display of the flexible display sheet. As will be described later, the pair of housings 1 are connected to a mounting plate (not visible in FIG. 1). Also, the pair of mounting plates are supported to be swingable relative to the base frame by a multi-axis hinge device B (not visible in FIG. 1) provided on the base frame. FIG. 1(b) is a perspective view of the mobile phone A when the pair of housings 1 are opened to an angle of approximately 180 degrees and the flexible display sheet 4 is unfolded (hereinafter, referred to as the unfolded state). Here, the length of the flexible display sheet 4 in the unfolded state in the direction of the arrow 4d is defined as the "face length." If the angle between the pair of housings 1 is set to 360 degrees, the result is FIG. 1(c). In FIG. 1(c), the flexible display sheet 4 is folded outward (hereinafter, referred to as the outward folded state), and the user can receive information displayed on the flexible display sheet 4 while maintaining the compactness of the mobile phone A. In the mobile phone A having the configuration shown in Figure 1(a), Figure 1(b), and Figure 1(c), the length of the device surface generally changes when the device is in an unfolded state, an inwardly folded state, or an outwardly folded state. As a result, the difference between the device surface length and the face length of the flexible display sheet 4 supported thereon (defined as the "face length difference") causes slack or tension in the flexible display sheet 4. In order to reduce the load applied to the flexible display sheet 4, a mechanism for reducing slack or tension caused by such a face length difference becomes important. 【0025】 2 is a plan view illustrating the multi-axis hinge device B, a pair of housings 1, and a pair of mounting plates 5 when the flexible display sheet 4 is in an unfolded state. In order to illustrate the multi-axis hinge device B, the flexible display sheet 4 and the like are omitted in FIG. The multi-axis hinge device B is composed of a hinge mechanism 7, a lock mechanism 8, a housing slide mechanism 9, a cover slide mechanism 10, a synchronization mechanism 11, a flexible display sheet guide mechanism 12, and a cover guide mechanism 13. The hinge mechanism 7, lock mechanism 8, housing slide mechanism 9, cover slide mechanism 10, and synchronization mechanism 11 are attached to the base frame 6 shown in FIG. 【0026】 The hinge mechanism 7 and the base frame 6 shown in Fig. 3 are screwed and fixed to each other through a mounting hole 6c of the base frame 6. A mounting hole 72a of a hinge arm 72 extending from the hinge synchronization portion 71 is screwed into a mounting screw hole 5a provided in a pair of mounting plates 5 shown in Fig. 3. Therefore, the pair of mounting plates 5 are supported so as to be swingable around an arrow 1b on a swing shaft 1a of the hinge arm 72. Since the hinge mechanism 7 is provided on the base frame 6, the pair of mounting plates 5 are supported so as to be swingable relative to the base frame 6. The swing shaft 1a of the hinge arm 72 is structured to swing and move within the hinge synchronization portion 71 in order to optimally realize three states of the pair of housings 1: an inwardly folded state, an unfolded state, and an outwardly folded state. 【0027】 The lock mechanism 8 and the base frame 6 are screwed together through the mounting hole 6e of the base frame 6. A lock arm 84 extending from a first joint 82 of the lock synchronization part 81 is connected to a pair of mounting plates 5 via a second joint 83, a lock joint 85, and a lock bracket 86. Specifically, the lock bracket 86 is positioned by a shaft (not shown) provided on the back surface of the lock bracket 86 and a positioning hole 5d of a pair of mounting plates 5 shown in FIG. 3, and is screwed together through a mounting hole 86a and a mounting screw hole 5c. The lock mechanism 8 is provided to maintain the inwardly folded state, the unfolded state, and the outwardly folded state, and each joint is provided with a load generating part that generates a movement load. Incidentally, by connecting the base frame 6 and the mounting plate 5 through a plurality of joints such as the first and second joints 82 and 83, overlapping fitting with the hinge mechanism 7 does not occur. 【0028】 The housing slide mechanism 9 and the base frame 6 are screwed together through the mounting holes 6d and 6e of the base frame 6. Here, the mounting hole 6e is fastened together with the lock mechanism 8 described above. The housing slide mechanism 9 pushes the pair of housings in the direction of the arrow 1c based on the transition from the outwardly folded state to the unfolded state to the inwardly folded state. This is a mechanism that reduces the slackness and tension of the flexible display sheet 4 that occurs as the outwardly folded state transitions from the unfolded state to the inwardly folded state. The housing slide mechanism 9 is composed of a slide arm 91a that is an open / close detection unit A91 that picks up the swing of the pair of mounting plates 5, an axially moving plate 92a that is a slide conversion unit A92 that converts the movement direction of the mounting plate 5 picked up by the slide arm 91a, and a tension bracket 93a that transmits the movement of the slide conversion unit A92 to the pair of housings 1, and the mounting hole 93ab of the tension bracket 93a is screwed into a mounting screw hole (not shown) provided in the pair of housings 1. With this structure, the housing slide mechanism 9 moves the pair of housings 1 in the direction away from the base frame 6. Therefore, the flexible display sheet 4 can receive an appropriate tension according to the amount of swing of the mounting plate 5. The details of the housing slide mechanism will be described later. 【0029】 The cover slide mechanism 10 is a mechanism for constantly pulling the cover 22 shown in FIG. 3 in the direction of the arrow 1c to remove slack in the cover 22 as it is folded outward, and is configured to urge a cover biasing portion 102 that screws into the ear portion 22a of the cover 22 in FIG. 3 in the direction of the arrow 1c by a tension elastic portion 101 such as a coil spring. 【0030】 The synchronization mechanism 11 and the base frame 6 are screwed into the mounting hole 6b of the base frame 6. The synchronization mechanism 11 has a pair of synchronization shaft pins 111 and a pair of synchronization gears 112 that mesh with each other and are centered on the pair of synchronization shaft pins 111. The synchronization mechanism 11 is provided to synchronize the swinging of the pair of mounting plates 5. 【0031】 The flexible display sheet guide mechanism 12 guides the flexible display sheet 4 so that it moves only in the direction of the arrow 1c and the opposite direction by having a flexible display sheet guide pin 122 fitted into a long hole 121 adhere to a protective sheet backed by the flexible display sheet 4. 【0032】 The cover guide mechanism 13 has a cover guide pin 132 fitted in a long hole 131 which fits into a guide hole 22b of the cover 22, thereby guiding the cover 22 so that the cover 22 moves only in the direction of the arrow 1c and the opposite direction thereto. 【0033】 3, the cover 22 is attached to the base frame 6 by screwing the mounting hole 22c into the mounting screw hole 6a of the base frame 6. Also, the cover 22 is attached to the mounting plate 5 by screwing the mounting hole 21a of the lower cover 21 into the mounting screw hole 5b of the mounting plate 5. Furthermore, the hooks 21b and 21c are engaged with the slide bracket 23 shown in FIG. 【0034】 The multi-axis hinge device B is composed of these multiple mechanisms, each of which plays a different role. Among these roles, the present invention will explain in detail the housing slide mechanism 9, which reduces slack and tension that occurs in the flexible display sheet 4 when it transitions from an outwardly folded state to an inwardly folded state via an unfolded state. 【0035】 Figure 4 is a diagram explaining the face length difference, where (a) is a schematic diagram of the state change of a flexible display sheet, and (b) is a diagram showing an example of the change in face length difference that occurs when transitioning from an outwardly folded state to an inwardly folded state. In Fig. 4, the flexible display sheet 4 transitions from a flexible display sheet 4a in an outwardly folded state having an arc c4a about an origin 41, through an unfolded state of a flexible display sheet 4b, to a flexible display sheet 4c in an inwardly folded state having an arc c4c. Fig. 4(b) is a graph showing a face length difference curve 42 during the transition, in which the horizontal axis 43 indicates the open / closed state of the housing 1 when the flexible display sheet 4 transitions from the outwardly folded state to the inwardly folded state, and the vertical axis 44 indicates the face length difference. 【0036】 In the face length difference curve 42 in Fig. 4(b), the change 42a in face length difference when the flexible display sheet 4 changes from the outward folded state 4a to the unfolded state 4b is smaller than the change 42b in face length difference when the flexible display sheet 4 changes from the unfolded state 4b to the inward folded state 4c. The reason why the change 42a in face length difference when the flexible display sheet 4 changes from the outward folded state to the unfolded state is small is because the flexible display sheet 4a and the arc c4a in the outward folded state are provided on the same side as the oscillation axis 1a with respect to the origin 41, and the radius of curvature of the arc c4a is large. In contrast, the reason why the change 42b in face length difference when the flexible display sheet 4c changes from the unfolded state to the inward folded state is large is because the flexible display sheet 4c and the arc c4c in the inward folded state are provided on the opposite side of the origin 41 with respect to the oscillation axis 1a, and the radius of curvature of the arc c4c is small. In addition, the change 42b in the difference in face length from the unfolded state to the inward folded state has many straight line regions because the radius of curvature of the arc c4c is small, and therefore the ratio of the length of the arc c4c to the folded length of the flexible display sheet 4 is small. 【0037】 When the face length difference curve 42 is not proportional to the opening / closing angle of the housing 1 as shown in FIG. 4(b), if a correction (face length difference correction) is made to reduce slack or tension proportional to the swing angle of the housing 1 as shown in Patent Document 1, a strong tension force will be applied to the flexible display sheet 4 during opening and closing of the housing, or conversely, large slack will occur. In the present invention, it has been found that in an electronic device that assumes an outwardly folded, unfolded, or inwardly folded state, the change in the face length difference of the flexible display sheet 4 changes according to the swing angle of the housing 1. In order to deal with this, the present invention is characterized in that, instead of performing a fixed face length difference correction according to the swing angle of the housing 1 as in Patent Document 1, the face length difference correction amount is changed (the rate of change is changed) according to the swing range of the housing 1. Specifically, when separating the pair of housings 1 from the base frame 6 according to the swing angle of the pair of housings 1, the housing slide mechanism 9 changes the amount of separation movement (hereinafter, separation movement amount) according to the swing range of the pair of housings 1. 【0038】 Fig. 5 shows an overall image of the housing sliding mechanism 9, where (a) is a perspective view of the housing sliding mechanism 9 when placed on the mounting plate 5, and (b) is a plan view of the housing sliding mechanism 9 when placed on the mounting plate 5. Fig. 6 is a plan view for explaining the operation of the axial moving plate and the conversion plate, which are part of the slide conversion part in the housing sliding mechanism. The arrangement of each member of the tension bracket 93a and part of the slide conversion part A92 that constitutes the housing sliding mechanism 9 will be explained using Figs. 5 and 6. 【0039】 [Arrangement of parts of the slide conversion portion A92 and tension bracket 93a] A holding frame 90a constituting the holding part A90 is attached to the base frame 6 (not shown). A slide arm 91a, which is the open / close detection part A91, is supported by the holding part A90 so as to be swingable around a swing shaft 1a. As shown in Figs. 6(a) and 7, the tip of the slide arm 91a is fitted with a slide arm shaft 91ab in a bearing 91ac as a first joint. As shown in Fig. 6(b), the slide arm shaft 91ab is also fitted with an axially moving plate 92a, and further, the tip of the slide arm 91a is clamped by a clamping part 92ab of the axially moving plate 92a. Therefore, when the slide arm 91a moves in the direction of the arrow 91b in Fig. 5(b), the axially moving plate 92a also moves in the same direction. A bearing portion 92ac along the axial slide shaft 92ae of the axial movement plate 92a is fitted with an axial movement plate shaft 94ac provided on the upper cover 94a, and is supported so as to be movable in the direction of the bearing portion 92ac and swingable around the bearing portion 92ac. With the axial movement plate 92a attached, the upper cover 94a is screwed to the mounting plate 5 through the mounting holes 94ab. 【0040】 The conversion plate 92c is supported by the mounting plate 5 so as to be swingable around the swing axis 92ca. An action axis 92ad provided on the back surface of the axially moving plate 92a in FIG. 6(b) is inserted into the long hole 92cd of the conversion plate 92c. Therefore, when the axially moving plate 92a moves in the direction of the arrow 92b, the conversion plate 92c swings around the swing axis 92ca. The tension bracket 93a shown in FIG. 5(b) is fitted with a slide axis 93ac provided on the mounting plate 5 by a bearing 93ad, and is supported so as to be slidable on the slide axis 93ac. An action axis 92cb of the conversion plate 92c is inserted into the long hole 93ae of the tension bracket 93a, and the tension bracket 93a slides on the slide axis 93ac due to the movement of the action axis 92cb accompanying the swing of the conversion plate 92c around the swing axis 92ca. The mounting hole 93ab of the tension bracket 93a is screwed into a mounting screw hole (not shown) of the housing 1. The axially moving plate 92a, the conversion plate 92c, an action cam portion 92e, a cam receiving portion 92f, a cam shaft 92g, a washer 92h, and a coil spring 92i, which will be described later, constitute a slide conversion portion A92. 【0041】 The operation of each of the above-described members when they transition from the unfolded state to the inward folded state will be described with reference to Figs. 【0042】 [Description of the operation of part of the slide conversion part A92 and the tension bracket 93a] When the pair of housings 1 is operated from the unfolded state shown in FIG. 5 to the inward folded state, the slide arm 91a swings around the swing shaft 1a in accordance with the swing of the mounting plate 5 connected to the pair of housings 1. The swing of the slide arm 91a is converted into the axial movement of the slide arm 91a in the direction of the arrow 91b by a cam mechanism described later. The axial movement plate 92a that clamps the slide arm 91a also moves axially in the direction of the arrow 92b in accordance with the axial movement of the slide arm 91a in the direction of the arrow 91b. The axial movement of the axial movement plate 92a causes the action shaft 92ad to bias the long hole 92cd of the conversion plate 92c. As a result, the conversion plate 92c swings around the swing shaft 92ca in the direction of the arrow 92d. 【0043】 The long hole 93ae of the tension bracket 93a is biased in the direction of the arrow 92d by the action shaft 92cb of the conversion plate 92c. As a result, the tension bracket 93a moves on the slide shaft 93ac in the direction of the arrow 1c. Here, the axial movement amount of the axial movement plate 92a is expanded to become the movement amount of the tension bracket 93a. This is because the distance between the swing shaft 92ca of the conversion plate 92c and the action shaft 92cb of the conversion plate 92c is sufficiently long compared to the distance between the swing shaft 92ca of the conversion plate 92c and the action shaft 92ad of the axial movement plate 92a, and the movement amount is expanded by the conversion plate 92c. In this way, the action of the tension bracket 93a accompanying the swing of the housing 1 relative to the base frame 6 causes the housing 1 to move in the direction away from the base frame 6 (arrow 1c). 【0044】 The movement of the slide arm 91a in the direction of the arrow 91b will now be described. First, the arrangement of each member of the holding portion A90, the open / close detection portion A91, and the slide conversion portion A92 that configure the housing slide mechanism 9 will be described with reference to FIGS. 【0045】 [Arrangement of the holding unit A90, the open / close detection unit A91, and the slide conversion unit A92] FIG. 7 is a perspective view of the cam portion and elastic portion which are part of the holding portion A90, the slide arm 91a, and the slide conversion portion A92 in the housing slide mechanism 9, (a) is a perspective view from above, and (b) is a perspective view from the back. FIG. 8 is an exploded perspective view of the holding portion A90, the slide arm 91a, and the cam portion and elastic portion which are part of the slide conversion portion A92 in the housing slide mechanism 9, as seen from the back. The slide arm 91a has a dog clutch 91ae which meshes with the action cam 92e (FIG. 8), and a pair of synchronization gears 91ad which mesh with each other and synchronize the pair of slide arms 91a. The action cam 92e may be integrated with the slide arm 91a, and the dog clutch 91ae may be omitted. Furthermore, the slide arm 91a has a bearing 91ac which is a first joint into which the slide arm shaft 91ab shown in FIGS. 7(a) and (b) is fitted, and a bearing 91af which is fitted axially slidably along a camshaft 92g described later. 【0046】 A camshaft 92g passes through a bearing 92eb of the action cam 92e and a bearing 91af of the slide arm 91a, and a coil spring 92i, which is an elastic part, is provided on the outer periphery coaxial with the camshaft 92g. The coil spring 92i is sandwiched between a pair of washers 92h through which the camshaft 92g passes. One of the pair of washers 92h abuts against a washer receiver 90ac of the holding frame 90a, and the other abuts against the slide arm 91a. The camshaft 92g is fitted into an axial groove 90ab of the holding frame 90a, and also passes through a bearing 92fa of the cam receiver 92f. 【0047】 Here, the coil spring 92i is charged by the washer 92h that is sandwiched between it and fitted into the holding frame 90a, and urges the slide arm 91a and the action cam 92e in the direction of the arrow 91c. Therefore, the action cam 92e and the cam receiver 92f are urged in opposition to each other. The lid 90b is attached to the holding frame 90a by screwing it with the screws 90c, the mounting holes 90ba, and the mounting screw holes 90ad. 【0048】 The operation of each of the above-described members when they transition from an inwardly folded state to an outwardly folded state via an unfolded state will be described with reference to Figs. 9(a), (b) and (c). 【0049】 [Operation description of the holding unit A90, the open / close detection unit A91, and the slide conversion unit A92] FIG. 9 is a perspective view for explaining the operation of the slide arm 91a in the housing slide mechanism 9, where (a) is a perspective view in the inwardly folded state, (b) is a perspective view in the unfolded state, and (c) is a perspective view in the outwardly folded state. Note that, since FIG. 9(a), (b), and (c) are perspective views seen from the back side, similar to FIG. 7(b), the folding direction of the slide arm 91a is opposite to that in the inwardly folded state in FIG. 1(a) and the outwardly folded state in FIG. 1(c). Here, when the slide arm 91a is swung from the inwardly folded state in FIG. 9(a) to the unfolded state in FIG. 9(b), the slide arm 91a starts to move in the direction of the arrow 91c due to the relationship between the cam inclination of the action cam 92e and the coil spring 92i. Then, when the slide arm 91a is swung from the unfolded state in FIG. 9(b) to the outwardly folded state in FIG. 9(c), the slide arm 91a further moves in the direction of the arrow 91c. This is because, as mentioned above, the coil spring 92i biases the slide arm 91a in the direction of the arrow 91c, and the action cam 92e is rotated by the slide arm 91a via the dog clutch 91ae, changing the contact surface between the cam inclined surface of the action cam 92e and the cam receiving portion 92f. 【0050】 The relationship between the swing angle of the slide arm 91a in Fig. 9 and the amount of movement of the slide arm 91a in the direction of the arrow 91c will be described with reference to Figs. 10(a) and 10(b). Fig. 10 is a diagram for explaining the inclination of the action cam 92e in the housing slide mechanism 9. Here, Fig. 10(a) is a perspective view of the slide arm 91a, the action cam 92e which is a part of the slide conversion part A92, and the coil spring 92i which is an elastic part, and is a diagram in which the holding part A90 is removed from the configuration of Fig. 9. Fig. 10(b) is an enlarged perspective view of the action cam 92e. In Fig. 10(a), the slide arm 91a is biased in the direction of the arrow 91c by the coil spring 92i, but the slide arm 91a cannot move in the direction of the arrow 91c because the cam surface 92ea of ​​the action cam 92e and the cam abutment surface 92fb of the cam receiving part 92f abut against each other and restrict the movement. When the rotation of the slide arm 91a is transmitted to the action cam 92e via the dog clutch 91ae, the cam surface 92ea of ​​the action cam 92e changes relative to the cam contact surface 92fb of the cam receiving portion 92f. Therefore, the slide arm 91a moves in the direction of the arrow 91c according to the amount of inclination of the cam surface. 【0051】 In the enlarged view of the action cam 92e in FIG. 10(b), the cam surface 92ea is divided into a cam area 92ec when the slide arm 91a swings from the outwardly folded state to the unfolded state, and a cam area 92ed when the slide arm 91a swings from the unfolded state to the inwardly folded state. The cam inclination amount of the cam area 92ec is set to be gentler than the cam inclination amount of the cam area 92ed. That is, the cam inclination amount is changed according to the rotation angle of the slide arm 91a. In general, the cam inclination amount according to the rotation angle of the slide arm 91a is set to be constant. However, as described above, in an electronic device that goes from the outwardly folded state to the unfolded state to the inwardly folded state, if the cam inclination amount is set to be constant, strong tension is applied to the flexible display sheet 4 when it transitions to the outwardly folded state, the unfolded state, and the inwardly folded state, or conversely, large slack is generated. In order to avoid this, the cam inclination amount according to the rotation angle of the slide arm 91a is changed based on the face length difference curve 42 shown in FIG. 4. By adopting this type of cam shape, the housing slide mechanism 9 is able to change the amount of separation movement depending on the swing range when separating the pair of housings 1 from the base frame 6 in accordance with the swing angle of the pair of housings 1. 【0052】 In the case sliding mechanism 9 of the present invention, the slide arms 91a are provided on the left and right, and if only one of them swings, the face length difference correction given to the flexible display sheet 4 cannot be properly performed. Therefore, a function is provided to synchronize the swing amount of the pair of left and right slide arms 91a. FIG. 11 is a diagram explaining the synchronization of the slide arms 91a in the case sliding mechanism 9, where (a) is a plan view of the slide arm 91a, the action cam 92e which is a part of the slide conversion part A92, and the coil spring 92i which is an elastic part, and (b) is a CC cross-sectional view of (a). As can be seen in FIG. 11(b), the synchronization gears 91ad provided on the pair of slide arms 91a mesh with each other. Therefore, even if a swing operation is applied to one slide arm 91a, the other slide arm 91a also swings by the same amount. By providing such a mechanism, the face length difference correction given to the flexible display sheet 4 can always be properly performed. 【0053】 As described above, in the multi-axis hinge mechanism of the present invention, a housing slide mechanism 9 is provided that separates the pair of housings 1 from the base frame 6 according to the swing angle of the pair of housings, and the housing slide mechanism 9 can correct the face length difference in all states, including the inwardly folded state, the unfolded state, and the outwardly folded state, by changing the amount of separation movement according to the swing range of the pair of housings 1. Note that the housing slide mechanism 9 in this embodiment is not limited to use in a multi-axis hinge device that combines various mechanisms described in FIG. 2, but can be applied to various hinge devices. [Industrial Applicability] 【0054】 The present invention is suitable for use as a multi-axis hinge device suitable for use in a foldable electronic device having a configuration in which a flexible display sheet is draped across a pair of housings, such as a mobile phone, an electronic organizer, a PDA, a netbook, a video display device, a portable game machine, a notebook computer, etc., and as a foldable electronic device using this multi-axis hinge device. The multi-axis hinge device according to the present invention is not limited to use in mobile phones, but can be widely used in foldable electronic devices having a configuration in which a pair of housings, each having a flexible display sheet attached to its surface, are connected to each other so as to be able to be opened and closed, as described above. [Explanation of symbols] 【0055】 1 Case 2 Rear cover 3 Switch 4 Flexible display sheet 5 Mounting plate 6 Base Frame 7 Hinge mechanism 8 Locking mechanism 9 Housing slide mechanism 10 Cover slide mechanism 11 Synchronization mechanism 12 Flexible display sheet guide mechanism 13 Cover guide mechanism 90a Retaining frame 90b lid 91a Slide arm 92a Axial movement plate 92c conversion plate 92e Action Cam 92f Cam receiving part 92g camshaft 92h Washer 92i coil spring 93a Tension bracket 94a Upper cover A Mobile phone B Multi-axis hinge device A90 Holding part A91 Open / close detector A92 Slide conversion part

Claims

[Claim 1] A multi-axis hinge device is used in an electronic device having a pair of housings with a flexible display sheet attached across both surfaces of the pair of housings, and connects the pair of housings so that the pair of housings can be opened and closed, the multi-axis hinge device having a base frame that is sandwiched between the pair of housings and supports each of the pair of housings so that the pair of housings can swing, and a housing slide mechanism that provides a separation movement amount that separates the pair of housings from the base frame in accordance with the swing angle of the pair of housings, and the housing slide mechanism changes the separation movement amount in accordance with the swing range of the pair of housings. [Claim 2] The multi-axis hinge device according to claim 1, characterized in that the housing slide mechanism changes the amount of separation movement in a region where the flexible display sheet transitions from an outwardly folded state to an unfolded state and in a region where the flexible display sheet transitions from an unfolded state to an inwardly folded state. [Claim 3] 2. The multi-axis hinge device according to claim 1, wherein the housing slide mechanism makes the amount of separation movement in a region where the flexible display sheet transitions from an outwardly folded state to an unfolded state smaller than the amount of separation movement in a region where the flexible display sheet transitions from an unfolded state to an inwardly folded state. [Claim 4] 2. The multi-axis hinge device according to claim 1, wherein the housing sliding mechanism is composed of a holding section provided on the base frame, a slide arm that swings according to a swing angle between the holding section and the pair of housings, a slide conversion section that converts the swing angle of the slide arm into the amount of separation movement, and a tension bracket that imparts the amount of separation movement of the slide conversion section to the pair of housings, and the slide conversion section changes the amount of separation movement according to a swing range of the slide arm. [Claim 5] 5. The multi-axis hinge device according to claim 4, wherein the slide conversion portion has a cam portion that sets the swing angle of the slide arm to the axial movement amount in the swing axis direction of the slide arm, and the cam inclination amount of the cam portion changes depending on the swing range of the slide arm. [Claim 6] 6. The multi-axis hinge device according to claim 5, wherein the slide conversion portion includes an axially moving plate that is swingably supported by the slide arm at a first joint and moves axially in response to the axial movement of the slide arm, and a conversion plate that converts the movement direction of the axially moving plate into the direction of the separation movement amount, and the conversion plate is connected to the tension bracket. [Claim 7] 7. The multi-axis hinge device according to claim 6, wherein the conversion plate amplifies the amount of movement of the axially moving plate to obtain the amount of movement of the tension bracket. [Claim 8] 8. An electronic device comprising the multi-axis hinge device according to claim 1.

Images