Hinge mechanism, parallel link mechanism, articulated support device, and method for assembling hinge mechanism

Abstract

To provide a hinge mechanism excellent in assemblability and capable of properly managing friction torque.SOLUTION: The hinge mechanism 60A, which connects the lower arm member 44 (first component) and the base end-side block 41 (second component) of the parallel link mechanism so as to be relatively rotatable about the rotation axis Xb, includes a pair of hinge units 65. Each hinge unit 65 includes a bracket 70 having a shaft receiving hole 72a, a shaft member 80 inserted into and supported by the shaft receiving hole 72a of the bracket 70 so as to be relatively rotatable, and a frictional torque generating mechanism 90 that generates frictional torque between the shaft member 80 and the bracket 70. The pair of shaft members 80 has a fixed shaft portion 82 and a support shaft portion 83. The support shaft portion 83 is provided with a friction torque generating mechanism 90. The fixed shaft portions 82 of the pair of shaft members 80 are coupled to each other by a coupling screw 100 supported by an 41y of a support hole of the base end-side block 41 in a state of being overlapped with each other. The brackets 70 of the pair of hinge units 65 are fixed to the lower arm member 44.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present invention relates to a hinge mechanism that connects two components so that they can rotate relative to one another, a parallel link mechanism that incorporates this hinge mechanism, an articulated support device that incorporates an arm that constitutes this parallel link mechanism, and a method for assembling the hinge mechanism. [Background technology]

[0002] The articulated support device disclosed in Patent Document 1 is configured by a base, a support that supports a support object, and a series of arms arranged between the base and the support, all of which are rotatably connected around a vertical or horizontal rotation axis. The arms include a first arm connected to the base so as to be horizontally rotatable around the vertical rotation axis, and a second arm connected to the tip of the first arm so as to be horizontally rotatable around the vertical rotation axis. The second arm forms a parallel link mechanism by connecting a base-end block, a tip-end block, and upper and lower arm members so as to be rotatable around four horizontal rotation axes, and by rotating the upper and lower arm members up and down relative to the base-end block, the support can be moved up and down while maintaining its orientation.

[0003] To suppress the vertical rotation of the second arm, at least one of the rotational links is required to be equipped with a friction torque generating mechanism, which is preferably located on both sides of the rotational link along the rotation axis to generate a large friction torque in a well-balanced manner.

[0004] In a hinge mechanism that rotatably connects two components, it is known to place friction torque generating mechanisms on both sides of the rotational connection, as shown in Patent Document 2. Briefly describing the hinge mechanism in Patent Document 2, the two components each have a pair of side plate portions spaced apart in the direction of the rotation axis. A pair of side plate portions of one component overlaps the inside of the pair of side plate portions of the other component. Two shaft members pass through these overlapping side plate portions. These shaft members are rotatable relative to the side plate portions of one component, but are non-rotatable relative to the side plate portions of the other component. Each of the two shaft members is provided with a friction torque generating mechanism. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 6150890 [Patent Document 2] Japanese Patent Application Laid-Open No. 2016-90001 Summary of the Invention [Problem to be solved by the invention]

[0006] In the hinge mechanism shown in Patent Document 2, the shaft member must be directly inserted through the two components, and then the friction torque generating mechanism must be attached to the shaft member, which makes the assembly of the hinge mechanism complicated. Also, it is difficult to properly control the friction torque. [Means for solving the problem]

[0007] In order to solve the above problem, the present invention provides a hinge mechanism that connects first and second components so that they can rotate relative to each other around a rotation axis, the hinge mechanism comprising a pair of hinge units, each hinge unit comprising a bracket having a bearing hole, an axial member that is inserted into and supported in the bearing hole of the bracket so that it can rotate relative to each other around the rotation axis, and a friction torque generating mechanism that generates friction torque between the axial member and the bracket, the brackets of the pair of hinge units being arranged opposite each other with a gap in the direction of the rotation axis and fixed to the first component, and the axial member of the pair of hinge units being fixed to the second component.

[0008] According to the above-described hinge mechanism, a pair of hinge units is used in which the shaft member and the friction torque generating mechanism are unitized via a bracket, which simplifies the assembly work to the first and second components. Furthermore, the friction torque of the friction torque generating mechanism can be adjusted before this assembly, allowing for appropriate management of the friction torque.

[0009] Preferably, each of the pair of shaft members has a fixed shaft portion arranged inside the bracket and a support shaft portion arranged outside the bracket, the fixed shaft portions of the pair of shaft members are fixed to the second component between the pair of brackets, and the friction torque generating mechanism is provided on each of the support shaft portions of the pair of shaft members. According to this configuration, the fixed shaft portions of the pair of shaft members and the second component are fixed between the pair of brackets, so that the fixing structure can be simplified.

[0010] Preferably, a first support hole extending perpendicular to the rotation axis is formed in the second component, the fixed shaft portions of the pair of shaft members overlap radially, and a connector inserted into the first support hole of the second component is connected to the overlapping fixed shaft portions. According to this configuration, a single connecting device can be used to connect the fixed shaft portions of the pair of shaft members to the second component, thereby further simplifying the fixing structure between the two and improving the workability of the fixing operation.

[0011] Preferably, the fixed shaft portions of the pair of shaft members each have a flat abutment surface arranged on a plane including the rotation axis, the fixed shaft portions of the pair of shaft members overlap with these abutment surfaces abutting, and a connecting screw serving as the connecting device passes through one fixed shaft portion and is screwed into the other fixed shaft portion. According to this configuration, the use of connecting screws makes it easier to fix the fixed shaft portions of the pair of shaft members to the second component.

[0012] Preferably, the second component has a second support hole that is coaxial with the rotation axis and connects to the first support hole, and the fixed shaft portions of the pair of shaft members each have a semicircular cross section, and when overlapped, provide a circular outer peripheral surface and are inserted and supported in the second support hole. According to this configuration, by inserting and supporting the fixed shaft portions of the pair of shaft members into the second support holes of the second component, the fixing operation using the connecting screws can be carried out smoothly.

[0013] Another aspect of the present invention is a parallel link mechanism having four components and four rotary joints, wherein the hinge mechanism having the above-described configuration is incorporated into at least one rotary joint.

[0014] Yet another aspect of the present invention is an articulated support device comprising a base at the base end, a support at the tip end that supports a support object, and a plurality of arms arranged between the base and the support that are connected so as to be capable of relative rotation, wherein one of the plurality of arms is formed by the parallel link mechanism described above, the four components are formed by a base end member, a tip end member, and upper and lower arm members that are bridged between the base end member and the tip end member, the four rotational connection parts each include a horizontal axis of rotation, and at least one of the upper and lower arm members is provided as the first component, and at least one of the base end member and the tip end member is provided as the second component.

[0015] Yet another aspect of the present invention is a method for assembling the above-described hinge mechanism, comprising the steps of: preparing the pair of hinge units whose friction torque generating mechanisms have been adjusted in advance; fixing the shaft members of the pair of hinge units to the second component; and fixing the brackets of the pair of hinge units to the first component so as to be opposed to each other and spaced apart in the direction of the rotation axis. [Effects of the Invention]

[0016] According to the present invention, a hinge mechanism having a pair of friction torque generating mechanisms can be assembled to two components with good workability, and the friction torque of the friction torque generating mechanisms can be appropriately managed. [Brief explanation of the drawings]

[0017] [Figure 1A] 1 is a perspective view showing a monitor support device according to one embodiment of the present invention, with the second arm in a substantially horizontal position. [Figure 1B] FIG. 10 is a side view of the monitor support device with the second arm positioned approximately horizontally. [Figure 2] FIG. 10 is a side view of the monitor support device showing the angular range of vertical rotation of the second arm. [Figure 3A] FIG. 10 is a perspective view of the monitor support device showing the stored state in which the second arm is arranged along the first arm. [Figure 3B] FIG. 2 is a side view of the monitor support device showing the stored state. [Figure 4] FIG. 2 is an enlarged side view showing the second arm with the outer cover omitted. [Figure 5] FIG. 2 is an enlarged side cross-sectional view of the second arm. [Figure 6] FIG. 6 is a cross-sectional view taken along the line VI-VI in FIG. 5. [Figure 7] FIG. 7 is a cross-sectional view showing a main part of FIG. 6 on a further enlarged scale. [Figure 8] FIG. 2 is an exploded perspective view of the second arm. [Figure 9]3 is an enlarged perspective view showing a pair of hinge units used in the second arm. FIG. [Figure 10] FIG. 2 is an enlarged perspective view of a shaft member of the hinge unit. DETAILED DESCRIPTION OF THE INVENTION

[0018] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A multi-joint monitor support device (articulated support device) according to one embodiment of the present invention will now be described with reference to the drawings. The monitor support device is used, for example, for medical purposes.

[0019] <General configuration and operation of the monitor support device> As shown in Figures 1A and 1B, the monitor support device comprises a base 10 at the base end, a support 20 at the tip end, and a first arm 30, a second arm 40, and a third arm 50 arranged in that order from the base 10 toward the support 20.

[0020] The base 10 has a flat mounting surface 10a, which is fixed to a cart 1 or the like (an object to be mounted). A monitor 2 (an object to be supported) is attached to the support 20. By rotating the arms 30, 40, 50 and the support 20, the monitor 2 can be adjusted to a desired orientation and position.

[0021] The first arm 30 is inclined, and its base end is connected to the upper end of the base 10 so as to be horizontally rotatable about a vertical rotation axis L1. The base end of the second arm 40 is connected to the tip of the first arm 30 so as to be horizontally rotatable about a vertical rotation axis L2. The base end of the third arm 50 is connected to the tip of the second arm 40 so as to be horizontally rotatable about a vertical rotation axis L3. A connecting portion 21 protrudes from the back surface of the support 20, and this connecting portion 21 is connected to the tip of the third arm 50 so as to be vertically rotatable about a horizontal rotation axis L4.

[0022] As will be described later, the second arm 40 constitutes a parallel link mechanism having four horizontal rotation axes. As shown in Figure 2, the second arm 40 rotates vertically around its base end, and the positions of the third arm 50 and the support 20 are adjusted in the up and down direction while maintaining their orientation and posture.

[0023] 3A and 3B, the monitor support device can be placed in a suitable storage position when not in use. That is, the second arm 40 is aligned with the first arm 30, and these arms 30, 40 are oriented so as not to interfere with the cart 1, and the support 20 and monitor 2 are oriented so as not to interfere with the arms 30, 40.

[0024] <Configuration of the second arm> As shown in Figures 4, 5, and 8, the second arm 40 comprises a base end block 41 (base end member; second component), a tip end block 42 (tip end member; second component), and an upper arm member 43 and a lower arm member 44 (first component) suspended between these blocks 41 and 42.

[0025] The base-end block 41 has a shaft 41a extending vertically downward, and this shaft 41a is inserted into a bearing portion at the tip of the first arm 30, thereby connecting the base-end block 41 to the first arm 30 so as to be horizontally rotatable about a rotation axis L2 that is vertical to the first arm 30. A friction torque generating mechanism 41b is provided on the shaft 41a, so that when the base-end block 41, and therefore the second arm 40, rotates relative to the first arm 30, a friction torque is generated to suppress the rotation.

[0026] A friction torque generating mechanism 42a is provided at the tip of the tip side block 42, and a third arm 50 is connected to the friction torque generating mechanism 42a via a support rod 42b thereof so as to be horizontally rotatable about a vertical rotation axis L3.

[0027] The base ends of the arm members 43, 44 are connected to the upper end of the base-end block 41 so as to be rotatable about horizontal rotation axes Xa, Xb, respectively. The tip ends of the arm members 43, 44 are connected to the base end of the tip-end block 42 so as to be rotatable about horizontal rotation axes Xc, Xd, respectively. The distance between the rotation axes Xa and Xb is equal to the distance between the rotation axes Xc and Xd, and the distance between the rotation axes Xa and Xc is equal to the distance between the rotation axes Xb and Xd. As a result, the blocks 41 and 42 and the arm members 43 and 44 form a parallel link mechanism.

[0028] The upper arm member 43 has an inverted U-shaped cross section, and the upper end of the base end block 41 is inserted between a pair of side walls at the base end, and is rotatably connected by a shaft member 45 extending along the rotation axis Xa. The base end of the tip block 41 is inserted between a pair of side walls at the tip of the upper arm member 43, and is rotatably connected by a shaft member 46 extending along the rotation axis Xc.

[0029] <Configuration of hinge mechanism> The base end of the lower arm member 44, which is shaped like a flat plate, is connected to the upper end of the base end block 41 by a hinge mechanism 60A according to the present invention so as to be rotatable about the rotation axis Xb. The distal end of the lower arm member 44 is also connected to the base end of the distal block 42 by a hinge mechanism 60B according to the present invention so as to be rotatable about the rotation axis Xd.

[0030] As shown in FIGS. 6 to 8, the hinge mechanism 60A has a pair of hinge units 65 arranged on both sides of the rotational connection along the rotational axis Xb. As shown in FIG. 9, each hinge unit 65 has a bracket 70, a shaft member 80, and a friction torque generating mechanism 90, and is unitized in advance before being incorporated into the base end block 41 and the lower arm member 44. The bracket 70 has a fixing plate portion 71 and a support plate portion 72 that is perpendicular to the fixing plate portion 71 .

[0031] As shown in FIG. 10, the shaft member 80 has a large-diameter flange 81 in the axially intermediate portion, a fixed shaft 82 formed on one side of the flange 81, and a support shaft 83 formed on the opposite side. The fixed shaft 82 has a semicircular cross section and has an abutment surface 82a and an arcuate surface 82b that function as described below. The abutment surface 82a is disposed on a plane passing through the central axis of the support shaft 83 (i.e., the rotation axis Xb). The arcuate surface 82b describes an arc centered on the central axis. The support shaft 83 has an oval cross section. A through-hole 82x is formed in the fixed shaft 82 of one hinge unit 65, and a screw hole 82y is formed in the fixed shaft 82 of the other hinge unit 65.

[0032] The base portion of the support shaft portion 83 of the shaft member 80 is inserted into a circular bearing hole 72a (see FIG. 7) formed in the support plate portion 72 of the bracket 70, thereby connecting the shaft member 80 to the support plate portion 72 of the bracket 70 so as to be rotatable relative to the support plate portion 72. The support shaft portion 83 protrudes from the support plate portion 72. The flange portion 81 of the shaft member 80 faces the support plate portion 72 on the side opposite the protruding side of the support shaft portion 83, via a washer 99 of the bracket 70 (see FIG. 7).

[0033] The friction torque generating mechanism 90 is provided on the support shaft portion 83 of the shaft member 80. More specifically, the friction torque generating mechanism 90 has a friction plate 91, a plurality of disc springs 92, a washer 93, and a nut 94, which are extrapolated in this order from the base of the support shaft portion 83 to the tip. The friction plate 91 has an oval hole that is the same cross-sectional shape as the support shaft portion 83, and the support shaft portion 83 is inserted into this hole so that the friction plate 91 rotates together with the support shaft portion 83. When a nut 94 threaded onto the tip of the support shaft portion 83 is tightened, the disc spring 92 is compressed via the washer 93, and the elastic force of the disc spring 92 is applied to the friction plate 91, pressing the friction plate 91 against the support plate portion 72 of the bracket 70. A friction torque (friction resistance) is generated between the friction plate 91 and the support plate portion 72 of the bracket 70.

[0034] The friction torque of the hinge unit 65 can be adjusted by the nut 94 in the final stage of assembling the hinge unit 65, and can be set accurately and easily to a desired friction torque. The support plate portion 72 of the bracket 70 is clamped between the flange portion 81 of the shaft member 80 and the friction torque generating mechanism 90 by the elastic force of the disc spring 92, so that the shaft member 80 is maintained in a stable inserted and supported state relative to the bracket 70.

[0035] <Hinge mechanism assembly process> The hinge mechanism 60A is assembled to the base end block 41 and the lower arm member 44 as follows. The base-end block 41 has a support hole 41x (second support hole) that is circular in cross section and coaxial with the rotation axis Xb, and a support hole 41y (first support hole) that extends in a direction perpendicular to the rotation axis Xb and is continuous with the support hole 41x. The end of the lower arm member 44 has a pair of fixing portions 44a that are spaced apart in the direction of the rotation axis Xb.

[0036] 7, the fixed shaft portions 82 of the pair of hinge units 65 are inserted into the support hole 41x of the base-end block 41 from both sides, and the fixed shaft portions 82 are overlapped in the radial direction so that the abutment surfaces 82a come into contact with each other. The arc surfaces 82b of the pair of fixed shaft portions 82 form a circular outer circumferential surface corresponding to the support hole 41x. At this time, the through hole 82x of one fixed shaft portion 82 and the screw hole 82y of the other fixed shaft 82 are coaxially aligned, and the through hole 82x and the screw hole 82y are also coaxially aligned with the support hole 42y of the base-end block 41. In this state, by passing the connecting screw 100 (connecting device) inserted into the support hole 42y through the through hole 82x of one of the fixed shaft portions 82 and screwing it into the screw hole 82y of the other fixed shaft portion 82, the fixed shaft portions 82 of the pair of hinge units 65 are connected to each other and fixed to the base end block 41 so that they cannot rotate relative to each other.

[0037] In the operation of fixing the fixed shaft portions 82 of the pair of shaft members 80 to the base-side block 41, the fixed shaft portions 82 can be easily positioned by inserting the fixed shaft portions 82 of the pair of shaft members 80 into the support holes 41x of the base-side block 41. Furthermore, by connecting the fixed shaft portions 82 of the pair of shaft members 80 with one another overlapping each other using a single connecting screw 100, the operation of fixing the pair of shaft members 80 to the base-side block 41 can be performed efficiently.

[0038] Next, the fixing plate portions 71 of the brackets 70 of the pair of hinge units 65 are fixed to the pair of fixing portions 44a of the lower arm member 44, respectively. Specifically, the support plate portions 72 of the brackets 70 are attached to the inner surfaces of the fixing portions 44a, and the fixing plate portions 71 are fixed to the lower surfaces of the fixing portions 44a. The ends of the support plate portions 72 of the brackets 70 protrude in the longitudinal direction from the fixing portions 44a of the lower arm member 44. A part of the base-end block 41 (the portion that supports the shaft member 80) is inserted between these protruding ends.

[0039] As described above, the shaft member 80 and the friction torque generating mechanism 90 are unitized via the bracket 70 using a pair of hinge units 65, and the shaft member 80 is fixed to the base end block 41, The assembly work of the hinge mechanism 60A is completed by fixing the bracket 70 to the lower arm member 44. Since the installation work of the friction torque generating mechanism 90 is not required in the final stage, the assembly work can be carried out efficiently.

[0040] The hinge mechanism 60B that rotatably connects the lower arm member 44 and the tip side block 42 has a configuration similar to that of the hinge mechanism 60A described above, and therefore the same components are given the same numbers and detailed description thereof will be omitted. As shown in Fig. 5, the base end of the tip side block 42 is formed with support holes 42x (second support holes) that support the fixed shaft portions 82 of the pair of hinge units 65, and also with support holes 42y (first support holes) that support the connecting screws 100.

[0041] <Function of the friction torque generation mechanism> The friction torque generating mechanism 90 suppresses relative rotation of the bracket 70 fixed to the lower arm member 44 with respect to the shaft members 80 of the pair of hinge units 60A fixed to the base-end block 41, thereby suppressing vertical rotation of the second arm 40. This allows the second arm to be stopped at a desired vertical rotation angle.

[0042] A large friction torque can be provided in a well-balanced manner by arranging the friction torque generating mechanisms 90 of the pair of hinge units 65 on both sides of the rotational connection between the base-end block 41 and the lower arm member 44. Furthermore, in this embodiment, a large friction torque can be provided in a well-balanced manner by arranging the friction torque generating mechanisms 90 of the pair of hinge units 65 on both sides of the rotational connection between the tip-end block 41 and the lower arm member 44.

[0043] <Other configurations> As shown in Figure 5, the second arm 40 has an assist mechanism 150 built in. This assist mechanism 150 assists the upward rotation of the second arm 40, but since it is well known and is not related to the gist of the present invention, only a brief explanation will be given. The assist mechanism 150 has a cam 151 provided on the base end block 41, a cam follower 152 that contacts this cam 151, and a spring 153 that urges the cam follower 152 toward the cam 151.

[0044] The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention. The present invention is not limited to parallel link mechanisms, but can be applied to any hinge mechanism between two components. Furthermore, parallel link mechanisms may be incorporated into support devices other than articulated support devices. When the present invention is applied to a parallel link mechanism, it is sufficient to incorporate the hinge mechanism of the present invention into at least one of the four rotary coupling parts, and there are no restrictions on the position. [Industrial Applicability]

[0045] The present invention can be applied to a parallel link mechanism of an articulated support device, etc. [Explanation of symbols]

[0046] 10 base 20 Support 30 First Arm 40 Second arm (parallel link mechanism) 41 base end block (base end member; second component) 41x support hole (second support hole) 41y support hole (1st support hole) 42 Tip block (tip member; second component) 42x support hole (second support hole) 42y support hole (1st support hole) 43 Upper arm member 44 Lower arm member (first component) 60A, 60B hinge mechanism 65 Hinge unit 70 Bracket 71 Fixed plate part 72 Support plate part 72a Bearing hole 80 Shaft member 82 Fixed shaft part 82a Contact surface 82b Arc surface 83 Support shaft part 90 Friction torque generation mechanism 100 Connecting screws (connectors)

Claims

1. A hinge mechanism that connects first and second components so as to be relatively rotatable about a rotation axis includes a pair of hinge units, Each hinge unit includes a bracket having a bearing hole, a shaft member inserted and supported in the bearing hole of the bracket so as to be relatively rotatable about the rotation axis, and a friction torque generating mechanism that generates friction torque between the shaft member and the bracket, the brackets of the pair of hinge units are disposed opposite to each other at an interval in the rotation axis direction and are fixed to the first component, A hinge mechanism, characterized in that the shaft members of the pair of hinge units are fixed to the second component.

2. 2. The hinge mechanism according to claim 1, wherein each of the pair of shaft members has a fixed shaft portion arranged inside the bracket and a support shaft portion arranged outside the bracket, the fixed shaft portions of the pair of shaft members are fixed to the second component between the pair of brackets, and the friction torque generating mechanism is provided on each of the support shaft portions of the pair of shaft members.

3. a first support hole extending in a direction perpendicular to the rotation axis is formed in the second component; 3. The hinge mechanism according to claim 2, wherein the fixed shaft portions of the pair of shaft members overlap radially, and a connector inserted into the first support hole of the second component is connected to the overlapping fixed shaft portions.

4. The hinge mechanism according to claim 3, characterized in that the fixed shaft portions of the pair of shaft members each have a flat abutment surface arranged on a plane including the rotation axis, the fixed shaft portions of the pair of shaft members overlap with these abutment surfaces abutting, and a connecting screw serving as the connecting device passes through one fixed shaft portion and is screwed into the other fixed shaft portion.

5. 5. The hinge mechanism according to claim 4, wherein a second support hole is formed in the second component, the second support hole being coaxial with the rotation axis and connected to the first support hole, and the fixed shaft portions of the pair of shaft members each have a semicircular cross section, and when overlapped, provide a circular outer circumferential surface, and are inserted into and supported by the second support hole.

6. A parallel link mechanism having four components and four rotary connecting parts, wherein the hinge mechanism according to any one of claims 1 to 5 is incorporated into at least one rotary connecting part.

7. An articulated support device comprising a base at a base end, a support at a tip end that supports a support object, and a plurality of arms arranged between the base and the support, connected to each other so as to be capable of rotating relative to one another, one of the plurality of arms is configured by the parallel link mechanism of claim 6, the four components are configured by a base end member, a tip end member, and upper and lower arm members spanning between the base end member and the tip end member, and the four rotational coupling portions each include a horizontal rotation axis, An articulated support device, characterized in that at least one of the upper and lower arm members is provided as the first component, and at least one of the base end member and the tip member is provided as the second component.

8. A method for assembling a hinge mechanism according to any one of claims 1 to 5, preparing the pair of hinge units in which the friction torque of the friction torque generating mechanism is adjusted in advance; a step of fixing the shaft members of the pair of hinge units to the second component; a step of fixing the brackets of the pair of hinge units to the first component so as to be spaced apart in the rotation axis direction and opposed to each other; A method for assembling a hinge mechanism, comprising:

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