JP3120899U - Hinge cam and hinge device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hinge cam which is small and has excellent strength and wear resistance, and also has excellent lubricity and can be used smoothly over a long period of time.
The above-mentioned problem consists of two cam pieces rotating with respect to one, the Vickers hardness of the cam surfaces facing each other is HV1200 to HV1500, and the surface roughness is 0.03 to 0. 0. This is achieved by a hinge cam with a friction coefficient of 1 μm and a range of 0.04 to 0.1.
[Selection] Figure 3

Description

  The present invention relates to a hinge cam and a hinge device used for a hinge portion of a folding device such as a folding cellular phone, an electronic dictionary, and a game machine.

  2. Description of the Related Art Conventionally, for example, there are the following hinges for folding devices.

  The hinge disclosed in Japanese Patent No. 3471743 is composed of a second disk that is sequentially mounted, and a coil spring that is interposed between a sliding cam piece, which is a member of the first disk, and a cylindrical main body on the same axis. Are arranged in a row, and by inserting a shaft rod into these constituent members and fixing them together in a state of retaining, the sliding cam piece is brought into elastic contact with the second disk by the elasticity of the coil spring, A spacing through space is formed between the sliding cam piece and the inner edge of the sliding cut groove in the cylindrical main body of the first disk. Thus, when the second member (cover) in the hinge device for opening and closing of the foldable device is opened and closed, the slide notch groove not provided in the axial direction from the side edge of the cylindrical main body is provided in the slide cut groove. The sliding cam piece is integrated so as to be movable in the above-described separated through space in the axial direction in the exposed state. By doing in this way, as long as the engagement composition is fitted to the first and second hinge cylinders with a simple operation, the engagement state is secured to the first and second hinge cylinders. As a result, the first and second members can be pivotably attached to each other, and the assembly operation of the hinge for holding the open / close of the folding device can be performed remarkably quickly and easily. In addition, by providing the second disk with a retaining elastic claw, the retaining state of the engaging composition is ensured.

  In the hinge disclosed in Japanese Patent Application Laid-Open No. 2005-140152, a cam convex part and a cam concave part are formed by a powder injection molding method using a metal or ceramic powdery material, thereby obtaining extremely precise dimensions. High wear resistance is obtained.

  In the hinge disclosed in Japanese Patent Application Laid-Open Nos. 2002-276642 and 2004-332919, the hinge cam is made of a hard (matrix hardness of HV500 or more) iron-based sintered alloy, and the cam surface state is a predetermined surface. Roughness (A surface roughness profile with a measurement length of 0.8 mm obtained by measuring the surface roughness is used. A straight line with a depth of 1 μm parallel to a straight line passing through two or more points on the top of the profile is crossed across the peak of the profile. The sum of the distances is 40 to 80%), and further, it is oil-impregnated, so that smooth operation is exhibited from the initial stage of use.

  In order to obtain such a hinge cam, the iron-based sintered alloy adopts a composition containing Cu and C or a carbon steel composition containing a strengthening element such as Cr, Mo, V, W, Ni, etc. The raw material powder is compacted and sintered, quenched and tempered, impregnated with lubricating oil, and subjected to parel polishing on the cam surface.

  A foldable mobile phone and other foldable mobile devices are required to be downsized year by year, and accordingly, a hinge as an opening / closing portion is also required to be downsized.

  In the hinge device described in Japanese Patent No. 3471743, the sliding cam piece 12B of the first disk is also provided for sliding that is not provided in the axial direction from the cylindrical main body 12A and the side edge 12c for the purpose of miniaturization. Since it is fitted in the notch groove 12d so as to be exposed and is slidably fitted in the axial direction, the sliding cam piece 12B can be inserted into the slide notch groove even if the diameter of the cylindrical body 12A is reduced. Since the diameter can be increased only in the exposed part to 12d, the rotational moment is efficiently received. However, in order to realize further downsizing, improvement of physical property values (hardness, wear resistance, etc.) of the sliding cam piece 12B and the second disk 13 has been demanded.

  As described in JP-A-2005-140152, if a sintered body of a powdered ceramic material is used for a cam, it can be hardened and wear resistance can be improved. If it is repeated several times, the cam irregularities may be lost, leading to a reduction in torque.

The cams described in Japanese Patent Application Laid-Open Nos. 2002-276642 and 2004-332919 also improve the operability when opening and closing the hinge device by improving the surface roughness of the cam surface. Yes, for example, when the cam diameter is 3 mm, when a force of about 40 N / mm ² spring force necessary to obtain the conventional click feeling and free stop torque is applied to the hinge device several tens of thousands of times, these documents In the iron-based sintered alloy cam described in 1), the abutting surface is worn, and there is a possibility that the torque is similarly reduced.

The object of the present invention is to solve the above problems and provide a hinge cam that is small, yet has excellent strength and wear resistance, and also has excellent lubricity and can be used smoothly over a long period of time. There is.

  The present invention provides a hinge cam that solves such problems. The hinge cam has a Vickers hardness of HV1200 to HV1500 or more, a surface roughness of 0.03 to 0.1 μm, and The friction coefficient is in the range of 0.04 to 0.1.

Vickers hardness is HV1200 to HV1500, surface roughness is 0.03 to 0.1 μm, and friction is applied so that the spring force of 40 N / mm ² is not worn or chipped even if it is continuously applied several tens of thousands of times. The coefficient was in the range of 0.04 to 0.1.

For example, by adopting a hinge cam according to the present invention as a hinge cam of a mobile phone or the like having a diameter of 3 mm to ⁴ mm, the contact surface is cut even when a force of about 40 N / mm ² is applied. In addition, the contact surface is not worn out, and a reduction in torque can be prevented.

  The cam of the present invention has a cam surface that is formed on the opposite cam surfaces of two cylindrical cam pieces, one of which rotates with respect to the other about the shaft portion. To do. The concave and convex portions are usually formed in the radial direction. The number is about 1-2. The two cam pieces have a diameter of 3 to 4 mm. The width (length in the axial direction) is determined by the application and is not particularly limited, but is usually about 1.5 to 2.5 mm.

  In the cam of the present invention, the Vickers hardness of the cam surface is HV1200 to HV1500.

  The surface roughness of the cam surface is 0.03 to 0.1 μm. The friction coefficient is 0.04 to 0.1.

  As the material of the cam piece, ceramic is preferable, and among them, zirconia is preferable. In the zirconia-based ceramic, the content of zirconia is 60% by weight or more, preferably 80% by weight or more, more preferably 90% by weight or more, and particularly preferably 95% by weight or more by weight of the oxide. Examples of components other than zirconia include yttrium oxide and alumina.

  The cam of the present invention can be obtained by forming a ceramic raw material powder, for example, zirconia-based ceramic, if necessary, zirconia powder with other components added by powder pressing, CIM, etc., and degreasing and sintering. it can. The sintered body was subjected to parel polishing in order to make the surface roughness 0.1 μm or less.

  Further, in order to make the friction coefficient 0.1 or less, a lubricant is applied to the cam surface.

The cam of the present invention can be used for various types of hinge devices, and includes, for example, a case, a coil spring, a sliding cam piece, a rotating cam piece, and a shaft member through which these are inserted.
Including a case, a friction plate, a coil spring, a sliding cam piece, a rotating cam piece, and a shaft member inserted therethrough,
The case has a bottomed cylindrical shape and is inserted into the shaft member so as to be rotatable with respect to the shaft member;
The friction plate is fixed to the shaft member so as to be interlocked with the rotation of the shaft member, and the case inner bottom surface is configured to generate friction with the case inner bottom surface as the shaft member rotates. It is provided at a position that touches
The coil spring is fitted in the case,
The sliding cam piece is inserted into the shaft member so as to be rotatable with respect to the shaft member, and is slidable in the axial direction in the case by being biased by the coil spring.
The rotating cam piece is fixed to the shaft member so as to interlock with the rotation of the shaft member, and is rotatable with respect to the sliding cam piece and the case,
A cam portion is formed between the sliding cam piece and the rotating cam piece to be engaged and disengaged with the rotation of the rotating cam piece.
The Vickers hardness of the cam surfaces of the sliding cam piece and the rotating cam piece facing each other is HV1200 to HV1500, the surface roughness is 0.03 to 0.1 μm, and the coefficient of friction is 0.04 to 0.1. It can use for the hinge apparatus characterized by being in.
This hinge device includes a case, a coil spring, a sliding cam piece, and a rotating cam piece, and has the following configuration.
(A) The case has a positioning recess or projection on the inner wall.
(B) The coil spring is fitted in the case.
(C) The sliding cam piece has a peripheral shape that can be fitted into the inner wall of the case, and is slidable in the axial direction in the case by being biased by a coil spring. .
(D) The peripheral surface of the sliding cam piece has a convex portion or a concave portion for suppressing rotation with respect to the case by fitting into a positioning concave portion or convex portion formed on the inner wall of the case.
(E) The rotating cam piece is rotatable with respect to the sliding cam piece and the case.
(F) A cam portion is formed between the sliding cam piece and the rotating cam piece to be engaged and disengaged with the rotation of the rotating cam piece.
(G) The cam portion formed on the sliding cam piece is formed so as to protrude outward from the outer peripheral surface of the sliding cam piece.
(H) The cam portion formed on the rotating cam piece has a radial length corresponding to the cam portion formed on the sliding cam piece.

  In such a hinge device, the friction coefficient of the cam cam is increased by providing a friction plate inserted into the shaft member and in contact with the inner bottom surface of the case, and can be stopped at a position other than the portion where the cam irregularities are fitted. . The friction pivot rotates with the shaft member and rubs against the inner bottom surface of the case to cause friction. However, the friction between the friction pivot and the case can be increased to achieve a free stop by reducing the friction of the cam. it can.

  The application of the cam of the present invention is not particularly limited, but for example, it can be preferably used for a hinge part of a mobile phone.

  A hinge cam according to an embodiment of the present invention will be described below with reference to the drawings.

  FIG. 1 is a schematic perspective view showing an example in which a hinge device 1 equipped with a cam according to an embodiment of the present invention is used in a mobile phone. A main body 2 and a cover 4 are formed so as to protrude from respective end portions. The hinge device 1 is inserted into the shaft tube pieces 3 and 5 so as to be rotatable.

  As shown in FIGS. 2 and 3, the hinge device 1 includes a case 10, a sliding cam piece 20, a rotating cam piece 30, a hook member 40, and a shaft member 50 through which these are inserted.

  As shown in FIGS. 3 and 4, the case 10 is a bottomed cylindrical member, and a circular insertion hole 11 for inserting the shaft member 50 is provided on the central axis of the base end surface. A coil spring 60 or the like for pressing the sliding cam piece 20 is inserted into the cylinder of the case 10. A circumferential groove of the case 10 is provided with a relief groove 12 cut out along the axial direction from the opening 10a to a predetermined position. Further, a positioning recess 13 is engraved on the inner circumferential surface of the case 10 along the axial direction from the opening 10a to a predetermined position. Further, a groove portion 14 extending along the axial direction is provided on the outer peripheral surface of the case 10. The positioning recess 13 and the groove 14 are arranged at positions shifted from each other so that the thickness of the case 10 does not become extremely thin.

  As shown in FIGS. 3 and 5, the sliding cam piece 20 is a cylindrical member that is slidably inserted into the opening 10 a of the case 10. A circular insertion hole 21 for inserting the shaft member 50 is provided on the central axis of the sliding cam piece 20.

  Further, the sliding cam piece 20 is provided with a convex cam 23 having a taper shape on an end surface (hereinafter referred to as a first cam surface 22) in the opposite direction to the case 10. The convex cam portion 23 extends in the radial direction symmetrically from the center axis position, and its end portion protrudes from the side peripheral surface of the sliding cam piece 20. The protruding portion 23 a of the convex cam portion 23 slides in the escape groove 12 of the case 10. Further, on the side peripheral surface of the sliding cam piece 20, a protruding protrusion 24 for positioning is provided along the axial direction. The positioning convex portion 24 engages with the positioning concave portion 13 of the case 10 and restricts the rotation of the sliding cam piece 20. The positioning convex portion 24 is slidable along the positioning concave portion 13.

  In order to obtain extremely high dimensional accuracy (roundness, etc.), the sliding cam piece 20 has a circle at the center of the cam as shown in FIG. 5 (d) in the longitudinal sectional view and FIG. 5 (e) in the bottom view. A ring-shaped gate 25 is provided around the mold insertion hole 21. At this time, the gate cut is provided slightly outside the insertion hole 21 so as not to adversely affect the insertion hole 21.

Further, the sliding cam piece 20 is provided with a ring-shaped molding portion 26 around the insertion hole 21 which is the same surface as the upper surface of the cam portion. This is due to the following reason. That is, firing is performed after powder molding. At this time, when the upper surface of the cam is turned upward, the protruding portion 23a on the outer periphery of the convex cam portion 23 slightly hangs down due to gravity. Then, the concave cam portion 33 comes into contact with the inner peripheral side of the convex cam portion 23, and the rotational torque becomes low because the sliding radius is small. Therefore, although it is desired to perform firing with the cam surface down, the convex cam portion 23 cannot be supported because the area corresponding to the upper surface is small.
Therefore, by providing a molding surface having the same height on the inner peripheral portion that does not contribute to the torque, the weight of the cam can be supported even when firing with the cam surface facing down. This ring-shaped molding 26 is a technique that is extremely difficult in press working, but is easy in powder molding. Further, the ring-shaped molded portion 26 has an action of lengthening the guide length when the insertion hole 21 of the sliding cam piece 20 slides to the central axis, and the inclination of the sliding cam piece 20 is increased or decreased by a strong spring force. It also has the effect of smoothing the slide operation. In addition, since the area of the upper surface part becomes large, the rotation cam piece 20 may be left as it is, and even if the lower surface side is down, it does not hang down because it has the same planar shape.

  As shown in FIGS. 3 and 6, the rotating cam piece 30 has a second cam surface 32 that contacts the first cam surface 22 of the sliding cam piece 20. The rotating cam piece 30 is a cylindrical member, and an oval insertion hole 31 for inserting the shaft member 50 is provided on the central axis thereof. A concave cam portion 33 that engages with the convex cam portion 23 of the sliding cam piece 20 is provided on the second cam surface 32 of the rotating cam piece 30. The concave cam portion 33 has a tapered shape having the same inclination angle as that of the convex cam portion 23, and can be engaged with each other with a constant frictional force when engaged. Further, in order to fix the rotating cam piece 30 so as not to rotate with respect to the cover 4, a groove portion 34 is provided on the outer peripheral surface along the axial direction.

  As shown in FIGS. 3 and 7, the hook member 40 is provided with an oval insertion hole 41 for inserting the shaft member 50 on the central axis. The hook member 40 is provided with a pair of hook-shaped hooks 42 and can be fixed by being hooked into the insertion portion 5 provided on the cover 4 of the mobile phone, for example. Note that the hook member 40 is not limited to the shape shown in FIG.

  As described above, the shaft member 50 is configured to penetrate the central axis of each member of the hinge device 1. As shown in FIGS. 3 and 8, the shaft member 50 includes a flange portion 51, a first round bar portion 52, a first fixing portion 53, a second round bar portion 54, and a second order in this order from the base end side. A fixed portion 55 and a narrowed tip portion 56 are formed. The flange portion 51 of the shaft member 50 has a diameter dimension that engages with the base end surface of the case 10. The first round bar portion 52 is a portion formed in a circular cross section and extends from the center position of the flange portion 51. When the case 10 is inserted, the circular insertion hole 11 of the first round bar portion 52 is rotatably fitted. The first fixing portion 53 is a portion formed in a cross-sectional oval shape following the first round bar portion 52. A friction plate 62, which will be described later, is fitted on the first fixing portion 53.

  The second round bar portion 54 is a part formed in a bar shape with a circular cross section, and the coil spring 60, the circular insertion hole 21 of the sliding cam piece 20, and the like are fitted on the outside. The second fixing portion 55 is a portion formed in a bar shape with a cross-sectional oval shape, and the oval-type insertion holes 31 and 41 of the rotary cam piece 30 and the hook member 40 are externally fitted. The narrowed tip 56 is configured to prevent the removal of each member by caulking this part when the hinge device 1 is assembled or by using a ring-shaped member.

  Among the above members, the sliding cam piece 20 and the rotating cam piece 30 are made of zirconia-based ceramic made of 97 mol% of zirconia and 3 mol% of yttrium oxide, and have a Vickers hardness of HV1200 to HV1500 and cam surfaces 22 and 32. The surface roughness is in the range of 0.03 to 0.1 μm, and the friction coefficient is in the range of 0.04 to 0.1. Both cam pieces 20 and 30 have a diameter of 3 mm. These cam pieces 20 and 30 are obtained by injection molding with CIM, sintering after degreasing, and barrel polishing according to a conventional method. A lubricant is applied to the cam surfaces 22 and 32. is there.

  All other members are made of SUS and plastic.

  Next, with reference mainly to FIG.2 and FIG.3, the detailed structure of this hinge apparatus 1 and the assembly method of each structural member are demonstrated.

  In the hinge device 1, the shaft member 50 is inserted into the circular insertion hole 11 of the case 10 through a plastic seat 61 having plasticity. The shaft member 50 can be positioned between each part of the shaft member 50 and each member to be mounted by inserting the base end portion of the plastic seat 61 and the case 10 until they contact the flange portion 51. In a state in which the case 10 is in contact with the flange portion, first, the plastic seat 61 and the base end portion of the case 10 are externally fitted to the first round bar portion 52 of the shaft member 50.

  Next, the friction plate 62 is inserted into the shaft member 50 in which the case 10 is inserted. In the friction plate 62, an insertion hole 62a that engages with the first fixing portion 53 of the shaft member 50 is formed at the center position. That is, the friction plate 62 is fitted to the first fixed portion 53 when the shaft member 50 is mounted on the shaft member 50, and interlocks with the rotation of the shaft member 50.

  A spring seat 63, a coil spring 60, and a sliding cam piece 20 are sequentially inserted into the second round bar portion 54 of the shaft member 50 and are arranged inside the cylinder of the case 10. At this time, the sliding cam piece 20 is inserted so that the positioning convex portion 24 engages with the positioning concave portion 13 of the case 10 and the protruding portion 23 a of the convex cam portion 23 engages with the clearance groove 12 of the case 10. Is done. The rotating cam piece 30 is further inserted into the second fixed portion 55 in the shaft member 50 into which the case 10 and the sliding cam piece 20 are inserted. The rotating cam piece 30 is inserted into the shaft member 50 so that the second cam surface 32 is in contact with the first cam surface 22 of the sliding cam piece. That is, the shaft member 50 is externally fitted in a state in which the convex cam portion 23 of the first cam surface 22 and the concave cam portion 33 of the second cam surface 32 are fitted.

  Further, the hook member 40 is inserted into the second fixing portion 55 of the shaft member 50. The rotary cam piece 30 and the oval insertion holes 31 and 41 of the hook member 40 are fitted and fixed to the second fixing portion 55 of the shaft member 50. For this reason, the rotating cam piece 30 and the hook member 40 rotate together with the shaft member 50 by opening and closing the cover 4 described later.

  Finally, the washer 64 is inserted into the narrowed tip 56 of the shaft member 50. The hinge device 1 inserted up to the washer 64 eliminates the removal of each member by caulking the tip end of the narrowed tip portion 54 with a hammer or the like or using a ring-shaped member.

  The hinge device is completed by assembling the members in accordance with the procedure as described above.

  As shown in FIG. 9A, a guide rail 3 a is extended on the inner peripheral surface of the shaft tube piece 3 in the main body 2 of the folding device. The hinge device 1 is inserted into the shaft tube piece 3, and the groove portion 14 of the case 10 is engaged and fixed to the guide rail 3a. In this fixed state, the hook member 40 and the rotating cam piece 30 of the hinge device 1 extend from the shaft tube piece 3 and are inserted into the shaft tube piece 5 of the cover 4. As shown in FIG. 9B, the shaft cylinder piece 5 of the cover 4 is provided with a guide rail 5 a on the inner peripheral surface in the same manner as the shaft cylinder piece 3. In the rotating cam piece 30, the groove 34 is engaged and fixed to the guide rail 5 a of the shaft piece 5. Further, in the hinge device, the hook 42 of the hook member 40 is hooked on the end portion of the guide rail 5a. With the configuration as described above, the main body 2 and the cover 4 are connected by the hinge device 1. In the illustrated example, the main body 2 and the cover 4 of the mobile phone are connected by a hinge device. In the illustrated example, the main body 2 and the case 10 of the mobile phone are engaged, and the cover 4, the rotating cam piece 30 and the hook member 40 are engaged, but the main body 2 and the rotating cam piece 30 are reversed. And the structure which the hook member 40 engages and the cover 4 and the case 10 engage may be sufficient.

  FIG. 10 is an enlarged side view showing a state of the sliding cam piece 20 and the rotating cam piece 30 before rotation of the hinge device, and FIG. 11 is a drawing of the sliding cam piece 20 and the rotating cam piece 30 during rotation of the hinge device. It is an enlarged side view which shows the state.

  Next, the operation of the hinge device will be described with reference mainly to FIGS.

  As described above, the hinge device 1 connects the main body 2 of the mobile phone and the cover 4 so as to be freely opened and closed. In a state where the main body 2 and the cover 4 of the cellular phone are closed, as shown in FIG. 10, the concave cam portion 33 of the rotating cam piece 30 and the convex cam portion 23 of the sliding cam piece 20 are fitted. At this time, the sliding cam piece 20 receives a pressing force from the coil spring 60 inserted into the case 10 and holds the rotating cam piece 30 in a locked state.

  When the cover 4 of the mobile phone is opened, the rotating cam piece 30 and the hook member 40 rotate with the movement of the cover 4 in the opening direction. Since the rotating cam piece 30 and the hook member 40 are engaged with the second fixing portion 55 of the shaft member 50, the shaft member 50 is also rotated at the same time.

  When the rotation of the rotating cam piece 30 starts, the fitting between the concave cam portion 33 and the convex cam portion 23 of the sliding cam piece 20 gradually shifts. As shown in FIG. 11, the concave cam portion 33 pushes up the convex cam portion 23 along the taper shape with this deviation. That is, the rotating cam piece 30 rotates to slide the sliding cam piece 20 toward the case 10 side. At this time, in the sliding cam piece 20, the protruding portion 23 a of the convex cam 23 slides on the escape groove 12 of the case 10. Further, the rotating cam piece 30 is rotated, and the concave cam portion 33 and the convex cam portion 23 are fitted again at a position rotated 180 degrees (a state where the cover 4 is opened 180 degrees). When the concave cam portion 33 and the convex cam portion 23 are fitted again, the coil spring 60 is urged, so that the convex cam portion 23 positively falls into the concave portion of the concave cam portion 33. . The movement of the convex cam portion 23 at this time becomes a click feeling and is effectively transmitted to the user.

  Here, the rotational torque during rotation of the rotary cam piece 30 is also transmitted to the sliding cam piece 20 that is in contact therewith. Therefore, the sliding cam piece 20 has a rotational force due to the rotational torque transmitted from the rotary cam piece 30. The rotational force acting on the sliding cam piece 20 positively brings the positioning convex portion 24 provided on the outer peripheral surface into contact with the positioning concave portion 13 of the case 10. That is, the positioning concave portion 13 of the case 10 receives the rotational force of the sliding cam piece 20 by contacting the positioning convex portion 24.

  For this reason, it is preferable that the positioning convex portion 24 and the positioning concave portion 13 have a configuration extending in the axial direction. By extending the positioning convex portion 24 and the positioning concave portion 13 in the axial direction, the rotational torque can be further dispersed.

  Note that the positioning recess 13 and the positioning projection 24 provided in the case 10 and the sliding cam piece 20 may be reversed. The case 10 may be provided with a positioning projection and the sliding cam piece 20 may be provided with a positioning recess.

  Moreover, it is preferable to form the outer peripheral surface of the sliding cam piece 20 in a shape and size that are fitted into the inner peripheral surface of the case 10 with a constant frictional force. With this configuration, the sliding cam piece 20 generates a certain frictional force due to surface contact with the case 10. For this reason, the rotational torque received from the rotating cam piece 30 can be diffused to the contact portion between the inner peripheral surface of the case 10 and the outer peripheral surface of the sliding cam piece 20.

  Furthermore, when the rotating cam piece 30 is stopped in the middle of rotation (a state in which the opening / closing movement of the cover 4 is stopped in the middle position), the convex cam portion 23 of the sliding cam piece 20 is rotated by the biasing force of the coil spring 60. The second cam surface 32 of the cam piece 30 is pressed. At this time, in the case 10, the friction plate 62 is pressed against the coil spring 60 via the spring seat 63. For this reason, the friction plate 62 functions as a brake that prevents the rotation cam piece 30 and the shaft member 50 from rotating, and can be fixed at the stop position.

  According to the above hinge device, since the protruding portion 23a of the sliding cam piece 20 enters the escape groove 12 of the case 10, the axial dimension is shortened, and the device can be downsized.

  In addition, the hinge apparatus of this invention is not limited to embodiment mentioned above, Of course, various application implementation or deformation | transformation implementation is possible as needed. For example, in the hinge device 1 of the present embodiment, the convex cam portion 23 and the concave cam portion 33 are fitted by rotating the rotary cam piece 30 by 180 degrees. It is good also as composition to do. Moreover, the shape of the convex cam part 23 and the concave cam part 33 can be formed in various shapes according to purposes, such as a rotational position.

  The cam of the present invention can be used for various hinges that perform cam operation. Examples of such hinges include those used for audio-related shutters of personal computers and automobiles in addition to folding cellular phones.

It is a perspective view which shows schematic structure of the mobile telephone to which the cam for hinges of this invention was applied. It is a figure which shows the structure of the hinge apparatus with which this cam for hinges is mounted | worn, (a) is a front view, (b) is side sectional drawing. It is a perspective view which shows the decomposition | disassembly state of the said hinge apparatus. It is a figure which shows the shape of the case of the said hinge apparatus. It is a figure which shows the shape of the sliding cam piece of the said hinge apparatus. It is a figure which shows the shape of the rotation cam piece of the said hinge apparatus. It is a figure which shows the shape of the hook member of the said hinge apparatus. It is a figure which shows the shape of the shaft member of the said hinge apparatus. It is a figure which shows the state which mounts the said hinge apparatus in a mobile telephone. It is an enlarged side view which shows the state of the sliding cam piece and rotation cam piece before rotation of the said hinge apparatus. It is an enlarged side view which shows the state of the sliding cam piece and rotation cam piece in rotation of the said hinge apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Hinge device 2 ... Main body 3 ... Shaft cylinder piece (main body)
3a ... Guide rail (main body)
4 ... Cover 5 ... Shaft cylinder piece (cover)
5a ... Guide rail (cover)
DESCRIPTION OF SYMBOLS 10 ... Case 10a ... Opening part 11 ... Circular insertion hole 12 ... Escape groove 13 ... Concave part for positioning 14 ... Groove part 20 ... Sliding cam piece 21 ... Circular insertion hole 22 ... 1st cam surface 23 ... Convex cam part 23a ... Projection part 24 ... Positioning convex part 25 ... Gate 26 ... Molding part 30 ... Rotating cam piece 31 ... Oval type insertion hole 32 ... Second cam surface 33 ... Concave cam part 34 ... Groove part 40 ... Hook member 41 ... Oval type insertion Hole 42 ... Hook 50 ... Shaft member 51 ... Flange part 52 ... First round bar part 53 ... First fixing part 54 ... Second round bar part 55 ... Second fixing part 56 ... Fine tip 60 ... Coil spring 61 ... Plastic seat 62 ... Friction plate 62a ... Insertion hole 63 ... Spring seat 64 ... Washer

Claims (8)

It consists of two cam pieces rotating on the other side, the Vickers hardness of the cam surfaces facing each other is HV1200 to HV1500, the surface roughness is 0.03 to 0.1 μm, and the friction coefficient is 0 Hinge cam in the range of .04 to 0.1 2. The hinge cam according to claim 1, wherein each of the cam pieces is made of ceramic. 3. A hinge cam according to claim 2, wherein the ceramic is zirconium. 4. The hinge cam according to claim 3, wherein the ceramic is zirconium-based, the zirconium content is 90% by weight or more by weight of the oxide, and at least contains yttrium oxide. 5. The hinge cam according to claim 1, wherein a lubricant is applied to the cam surface. The hinge cam according to any one of claims 1 to 5, wherein the cam piece has a diameter of 3 to 4 mm. The hinge cam according to any one of claims 1 to 6, which is attached to a case of a mobile phone. Including a case, a friction plate, a coil spring, a sliding cam piece, a rotating cam piece, and a shaft member inserted therethrough,
The case has a bottomed cylindrical shape and is inserted into the shaft member so as to be rotatable with respect to the shaft member;
The friction plate is fixed to the shaft member so as to interlock with the rotation of the shaft member, and the case inner bottom surface is configured to generate friction with the case inner bottom surface with the rotation of the shaft member. It is provided at a position that touches
The coil spring is fitted in the case,
The sliding cam piece is inserted into the shaft member so as to be rotatable with respect to the shaft member, and is slidable in the axial direction in the case by being biased by the coil spring.
The rotating cam piece is fixed to the shaft member so as to interlock with the rotation of the shaft member, and is rotatable with respect to the sliding cam piece and the case,
A cam portion is formed between the sliding cam piece and the rotating cam piece to be engaged and disengaged with the rotation of the rotating cam piece.
The Vickers hardness of the cam surfaces of the sliding cam piece and the rotating cam piece facing each other is HV1200 to HV1500, the surface roughness is 0.03 to 0.1 μm, and the friction coefficient is 0.04 to 0.1. A hinge device characterized by that.

Images