JP2003004078A - Rotating damper and device using it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotating damper which gives a large braking torque only in one direction with simple structure. SOLUTION: In the rotating damper 1a comprised of a braking plate 5a rotatably stored in a case 3 packed with liquid and a rotating shaft 4 engaged or integrally formed with the braking plate 5, the braking plate 5 has at least an impeller blade part 6a expanding from the rotating shaft 4 to a circumference direction, the impeller blade part 6a has an end face A receiving the load of fluid when revolving in a direction and an end face B receiving the load of fluid when revolving in the reverse direction, the end face A and the end face B differ only in thickness, and are formed by binding each end face thereof in shape of plane or curved surface or combination of both.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary damper that applies a braking force to the movement of a rotating portion or a linear moving portion of various open / close doors, a drawer of a storage box, and the like to allow the dampers to operate gently.

[0002]

2. Description of the Related Art (Prior Art 1) Conventionally, as shown in FIG. 14, a braking plate hermetically sealed in a cylindrical case 3 filled with a viscous fluid 2 and the braking plate are integrally formed. In the rotary damper configured with the rotary shaft 1, the planar shape of the braking plate is a shape obtained by cutting two points facing the center of the disc with parallel straight lines, or a cross-shaped blade portion 4 is provided. Things are widely known. In such a rotary damper, the shear resistance of the viscous fluid 2 generated in the gap between the braking plate and the case 3 is used. However, by cutting a part of the circle instead of the circular shape as described above, only the shear resistance is cut. Not only that, the load of the viscous fluid 2 generated on the cross section of the braking plate could also be generated. Further, in order to increase the braking torque in such a rotary damper, the gap between the braking plate and the case 3 may be reduced, or the volume of the filling portion may be increased to use a large braking plate. And viscous fluid 2
Was packed in large quantities. Here, the value of the braking torque differs depending on the shape and viscosity of the braking plate.

(Prior Art 2) Further, as a rotary damper in which the magnitude of the braking torque is different depending on the rotating direction, Japanese Patent Laid-Open No. 8-1 is available.
The invention described in Japanese Patent No. 93458 is known. According to the present invention, a wing member is provided which can be radially rotated from a rotating body by a predetermined angle with respect to a rotating shaft. By rotating to increase the load generated on the wing member, and when the rotating body rotates to the other side, by rotating with respect to the rotating body so that the radius becomes the minimum, and reducing the load generated on the wing member, Different braking torques are obtained depending on the rotation direction.

[0004]

DISCLOSURE OF INVENTION Problems to be Solved by the Invention In various open / close doors, drawers for storage boxes, etc., when a door is opened by a spring member or its own weight by pressing an operation button, the door suddenly opens. Is used. Here, when the door is opened, the braking torque of the damper is required because it operates slowly, but when the door is closed, the braking torque of the damper does not act because the door is closed quickly. desirable.

However, in Conventional Example 1, since the braking torques acting on the forward and reverse rotations are the same, the structure of the damper cannot realize the case where the braking torque is required only in one direction. It was

Further, in Conventional Example 2, since the radius of rotation is determined by the region in which the blade member rotates, in order to increase the difference between the braking torques acting on the forward and reverse rotations, the rotary damper has a large radial dimension. There was a need. Furthermore, since the number of constituent parts is large, the manufacturing cost is high, and the rotary part is provided, it is difficult to say that the durability is excellent. An object of the present invention is to provide a rotary damper that has a simple structure and applies a large braking torque only in one direction.

[0007]

SUMMARY OF THE INVENTION The present invention comprises a braking plate rotatably housed in a case filled with fluid, and a rotary shaft that is engaged with or integrally formed with the braking plate. In the rotary damper, the braking plate has at least one or more blade portions extending in the peripheral direction from the rotation shaft, and the blade portion has an end face R that receives a fluid load when the braking plate rotates in one direction, It has an end face L that receives a fluid load when it is rotated in the opposite direction, and the end face R and the end face L have different thicknesses, and the end faces L and L are connected by a flat surface, a curved surface, or a combination of both. It is a feature. The end face R and the end face L may be flat or curved. The fluid may be a gas or a fluid that can be controlled by electromagnetic force.

With this configuration, the shape of the vane portion that pushes the fluid away differs depending on the direction of rotation, so the flow of fluid in the case differs depending on the direction of rotation, and the resulting braking torque also differs. Therefore, according to the present invention, it is possible to easily generate different braking torques depending on the rotation direction, only by changing the shape of the blade portion.

Here, it is desirable that one of the two end faces of the blade portion has a thickness close to zero.

With this configuration, the cross section becomes triangular and the amount of fluid pushed by the blades remarkably differs depending on the rotation direction. As a result, the difference in the braking torque acting on the forward and reverse rotations is particularly remarkably generated. You can

Further, it is desirable that a part of the blade portion is provided with a flat surface portion that substantially matches the total thickness of the blade portion and faces the case upper surface or the case lower surface in parallel.

With this configuration, the shear resistance of the fluid generated in the gap between the braking plate and the case can be increased, and as a result, the braking torques acting on the forward and reverse rotations can be kept different from each other. The torque value can be increased. In addition, the value of the braking torque can be adjusted by changing the range of the flat portion.

Furthermore, it is desirable to use the rotary damper according to any one of claims 1 to 3 in combination with an energy storage member such as a spiral spring or a mainspring.

With this configuration, the rotary damper has
The braking torque by the damper and the torque by the energy input / output of the energy storage member are generated.

For example, as the energy storage member,
The case where the mainspring is applied will be described. When the mainspring can be unwound, a large braking torque is applied by the damper, and the mainspring can be gently unwound. On the other hand, when the mainspring is wound up, a large force is required because it is performed against the spring force of the mainspring and the braking torque by the damper.

According to the present rotary damper, since the braking torque of the damper can be reduced, the mainspring can be made with a relatively small force.
Can be rolled up quickly.

Further, the operation of winding the mainspring is often due to human power, but the power has large variations. For example, when a strong person tries to wind at a high speed, the load on the damper increases in proportion to the speed, and an excessive load is added to the damper. According to the present rotary damper, since the braking torque can be reduced, the load applied to the damper is also reduced, and it is possible to prevent damage or the like.

Further, the rotary damper according to any one of claims 1 to 4 is a device for opening and closing doors of various devices and a drawer for a storage box, which performs an operation in either the opening direction or the closing direction by a spring member or its own weight. It is desirable to use it for such purposes.

With this configuration, the braking torque by the damper can be increased in the direction in which the damper is actuated by the spring member and its own weight, and the braking torque by the damper can be decreased in the opposite direction.

A case where the present invention is applied to, for example, a toilet seat will be described. Since a large braking torque is applied by the rotary damper in the direction in which the toilet seat closes by its own weight, the toilet seat can be prevented from closing suddenly and can be operated gently. In addition, since the braking torque by the rotary damper is small in the direction of opening the toilet seat manually, the toilet seat can be quickly opened with a small force.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings.

[First Embodiment] FIG. 1 is a perspective view showing the structure of a rotary damper according to a first embodiment of the present invention. The present rotary damper is such that the obtained braking torque is different depending on the rotation direction of the rotary shaft 1.

The rotary shaft 1 is made of polyacetal resin,
It is rotatably supported by a case 3 which is also made of polyacetal resin. The case 3 includes a case body 3a having a bottomed cylindrical shape filled with high-viscosity viscous fluid 2 such as grease and oil, and a case lid 3b attached to the case body 3a so as to cover the open end surface of the case body 3a. Become. A braking plate made of polyacetal resin that is integrated with the rotating shaft 1 is housed in the case 3. Also,
This braking plate has two pairs of blade portions 4 extending in the peripheral direction from diagonal positions on the outer peripheral surface of the rotating shaft 1.

2 and 3 show streamlines of the viscous fluid 2 in the case 3 when the blade portion 4 of the rotary damper of the first embodiment is rotated. The vane portion 4 has a trapezoidal cross-section so that the thin end surface R4a receives the fluid load when the vane portion 4 rotates in one direction, and the thick end surface L4b receives the fluid load when the vane portion 4 rotates in the opposite direction. . 2 shows the flow of the viscous fluid 2 when the blade portion 4 rotates in the direction of the end surface R4a of the trapezoidal cross section (direction of arrow A), and FIG. 3 shows the flow of the viscous fluid 2 in the direction of rotation of the end surface L4b of the trapezoidal cross section (direction of arrow B). FIG.

As shown in FIGS. 2 and 3, since the flow of the viscous fluid 2 in the case 3 is different depending on the rotation direction of the present rotary damper, the normal rotation direction and the reverse rotation direction are different as shown by the one-dot chain line in FIG. Generates braking torque. As shown in FIGS. 2 and 3, the end surface R4a and the end surface L4b push the viscous fluid 2 away in the rotation direction of the blade portion 4, but the inclined surface 4c pushes the viscous fluid 2 away in the case body 3a direction and the case lid 3b direction. . The viscous fluid 2 pushed away in the direction of the case body 3a and the direction of the case lid 3b causes the blade portion 4 and the case body 3 to move.
The flow velocity between the blade portion 4 and the case lid 3b is increased between a and the shear resistance is increased.

That is, when the blade portion 4 rotates in the direction of arrow A in FIG. 2, shearing resistance increases due to the inclined surface 4c, and a relatively large braking torque as shown by the chain line A in FIG. 4 is generated. On the other hand, when the viscous fluid 2 rotates in the direction of arrow B in FIG.
A small amount of the viscous fluid 2 is pushed away in the direction of the case body 3a and the direction of the case lid 3b, and a relatively small braking torque as shown by the chain line B in FIG. 4 is generated.

Thus, according to this embodiment, the blade portion 4
It is possible to generate different braking torques depending on the rotation direction simply by making the cross-sectional shape of the trapezoidal. Also, the end face R
By changing the thickness ratio between 4a and the end surface L4b, it is possible to adjust the difference between the braking torques generated in the normal and reverse rotations.

Here, the number of the blade portions 4 is not limited, but it is desirable to have two or more blade portions 4 in order to obtain a stable braking torque. Further, an oil seal may be attached to the rotary shaft 1 in order to prevent liquid leakage of the viscous fluid 2 and intrusion of dust from the outside. Although the rotating shaft 1 and the braking plate are integrated in this embodiment, they may be engaged with each other as shown in the scope of the invention.

In this embodiment, the rotary shaft 1, the case 3, and the braking plate are made of polyacetal resin because of its good oil resistance, but the material is not limited to this and may be made of metal or ceramic. In the present embodiment, the viscous fluid 2 is used as the fluid with which the case 3 is filled, but the fluid is not limited to this and may be another fluid. Further, it may be a fluid whose viscosity can be controlled by electromagnetic force. In this embodiment, the rotary shaft 1, the case 3 and the braking plate are manufactured by cutting,
The manufacturing method is not limited to a specific processing method, and manufacturing by pressing, injection molding or the like is also possible.

As an example of the method of assembling the present rotary damper, the fixed case body 3a houses the braking plate integrated with the rotary shaft 1, the case body 3b is filled with the viscous fluid 2, and the case lid 3b is covered with the case. Although there is a method of fitting and fixing to the main body 3a, the rotary damper of the present invention does not particularly limit the assembling method, and the order of the steps may be changed, or a jig or an instrument may be used.

[Second Embodiment] FIG. 5 is a perspective view showing the structure of a rotary damper according to a second embodiment of the present invention. The first
The same parts as those in the embodiment are designated by the same reference numerals, and detailed description thereof will be omitted. The rotary damper of the second embodiment is a modification of the shape of the braking plate of the rotary damper of the first embodiment. The braking plate has two pairs of blade portions 4 extending in the peripheral direction from diagonal positions on the outer peripheral surface of the rotating shaft 1.

6 and 7 show streamlines of the viscous fluid 2 in the case 3 when the blade portion 4 of the rotary damper of the second embodiment is rotated. The cross-sectional shape of the vane portion 4 is such that the triangular acute angle portion 4d receives the fluid load when the vane portion 4 rotates in one direction, and the fluid load is received by the triangular bottom side 4e when the vane portion 4 rotates in the opposite direction. It is a triangle. 6 shows the flow of the viscous fluid 2 when the blade portion 4 rotates in the direction of the acute angle portion 4d (direction of arrow C) of the triangular cross section, and FIG. 7 shows the flow of the viscous fluid 2 when rotating in the direction of the base 4e of the triangular cross section (direction of arrow D). FIG.

As shown in FIGS. 6 and 7, since the flow of the viscous fluid 2 in the case 3 is different depending on the rotation direction in the present rotary damper, the normal rotation direction and the reverse rotation direction are different as shown by the solid line in FIG. Generates braking torque. That is, the blade portion 4 is shown in FIG.
When the viscous fluid 2 rotates in the direction of arrow C, the viscous fluid 2 moves in the direction of the case body 3a and the case lid 3b along the acute angle portion 4d of the triangular cross section.
Since it is pressed in the direction, a vortex is generated behind the blade portion 4 and a large braking torque as shown by the solid line C in FIG. 4 is generated. On the other hand, when rotating in the direction of arrow D in FIG.
Moves in parallel with the bottom side 4e of the triangular cross section in the rotation direction, so that the viscous fluid 2 pressed against the case body 3a direction and the case lid 3b direction is small, and a small braking torque as shown by the solid line D in FIG. 4 is generated.

As described above, by making the cross-sectional shape of the vane portion 4 triangular, the difference in braking torque generated in forward and reverse rotations can be particularly remarkably generated.

In the second embodiment, the vane portion 4 has a triangular cross-sectional shape, but the present invention is not limited to this and embodiments can be made within the scope of the present invention. For example, the cross-sectional shape may be wedge-shaped, semi-circular, bow-shaped, or fan-shaped, or one side of a triangle may be an inferior arc.

[Third Embodiment] FIG. 8 is a perspective view showing the structure of a rotary damper according to a third embodiment of the present invention. The second
The same parts as those in the embodiment are designated by the same reference numerals, and detailed description thereof will be omitted. The rotary damper of the third embodiment is a modification of the braking plate shape of the rotary damper of the second embodiment. The braking plate has a pair of blade portions 4 extending in the circumferential direction from diagonal positions on the outer peripheral surface of the rotating shaft 1.

9 and 10 show the viscous fluid 2 in the case 3 when the blade portion 4 of the rotary damper of the third embodiment is rotated.
This shows the streamline of. The cross-sectional shape of the vane portion 4 has an acute-angled portion 4d and a bottom side 4e, like the cross-sectional shape of the second embodiment. Further, a plane portion 4f having the same thickness as the bottom side 4e is provided between the acute angle portion 4d and the bottom side 4e. Here, the plane portion 4f faces the case body 3v and the case lid 3w in parallel. FIG. 9 shows the blade portion 4.
10 rotates in the direction of the acute-angled portion 4d of the triangular cross section (direction of arrow E), FIG.
It is a figure explaining the flow of the viscous fluid 2 when rotating to the (direction).

As shown in FIGS. 9 and 10, in the present rotary damper, the viscous fluid 2 passes through the narrow gap between the flat surface portion 4f and the case 3 by the rotation in both directions of the arrow E and the arrow F. Shear resistance occurs. The braking torque becomes larger than that of the rotary damper of the second embodiment by the shearing resistance generated in the flat surface portion 4f, and as shown by broken lines E and F in FIG. Get the torque.

As described above, by providing the plane portion 4f in the cross-sectional shape of the vane portion 4 of the second embodiment, the braking torque larger than that of the second embodiment is provided while having the difference in the braking torque of the forward and reverse rotations. Torque can be obtained.

Further, it is possible to obtain a larger braking torque by adjusting the area of the flat portion 4f.

[Fourth Embodiment] FIG. 11 is a sectional view of a rotary damper according to a fourth embodiment of the present invention. The same parts as those in the second embodiment are designated by the same reference numerals and detailed description thereof will be omitted. The rotary damper according to the fourth embodiment is the same as the rotary damper according to the second embodiment except that the holding cylinder 10 made of polyacetal resin and the cylindrical lid 11 made of polyacetal resin are used.
A steel true 12 and a stainless steel spring 13 are provided.

The holding cylinder 10 has a bottomed cylindrical shape, and is attached to the case body 3a so that the bottom surface of the holding cylinder 10 covers the open end surface of the case body 3a. Further, a cylinder lid 11 is attached to the holding cylinder 10 so as to cover the open end surface of the holding cylinder 10. Further, the holding cylinder 10 accommodates the mainspring 13 therein, and a groove for engaging the outer end of the mainspring 13 is provided in a part of the inner peripheral surface thereof.

Further, the center 12 of the holding cylinder 10 and the center of the cylinder lid 11 rotatably support the stem 12. One end of the stem 12 is engaged with the rotary shaft 1, and a gear 14 is attached to the other end protruding from the holding cylinder 10. Further, an engaging portion 12a for engaging the inner end of the mainspring 13 is provided on the outer peripheral surface of the stem 12.

In this way, since the true shaft 12 and the rotary shaft 1 are engaged and rotate, the braking torque by the braking plate can be obtained as the mainspring 13 is wound up or unwound. A spiral spring is incorporated so that when the gear wheel 14 rotates in the direction in which the spiral spring 13 is wound up, it rotates in the direction of the acute angle portion 4d (arrow C direction) of the triangular cross section of the blade portion 4.

Although the rotary shaft 1 and the true shaft 12 are engaged with each other in this embodiment, they may be integrated. Further, although the rotary shaft 1 and the inner end of the mainspring 13 are engaged with each other in this embodiment, they may be integrated. Similarly, although the inner peripheral surface of the holding cylinder 10 and the outer end of the mainspring 13 are engaged with each other in this embodiment, they may be integrated.

In this embodiment, the holding cylinder 10 and the cylinder lid 11 are made of polyacetal resin, and the true 12 is steel.
The material is not particularly limited, and other materials may be used. Further, the mainspring 13 is not limited to stainless steel, and other materials such as carbon steel may be used.

Further, although the holding cylinder 10, the cylinder lid 11, and the stem 12 are all formed by cutting, they may be manufactured by other processing methods. In the present embodiment, the holding cylinder 10 is fixed to the case body 3a and the cylinder lid 11 is fixed to the holding cylinder 10 by fitting, but the present invention is not limited to this, and a fixing method such as press fitting may be used. .

An example of the method of assembling the present rotary damper will be introduced below. The holding cylinder 10 is fixed to the case body 3a of the rotary damper of the second embodiment. Winded up mainspring 1
The stem 12 engaged with 3 is inserted into the holding cylinder 10 so as to engage with the rotating shaft 1. In addition, at the time of insertion, the mainspring 13 is inserted while being unwound, and the holding cylinder 10 is fitted with a cylinder lid 11
Attach. By rotating the true 12, the mainspring 13
The outer end of is engaged with the groove on the inner peripheral surface of the holding cylinder 10. The rotary damper of the present invention is not particularly limited to the above-mentioned assembling method, and the order of the steps may be changed, or a jig or an instrument may be used.

FIG. 12 is a side view of the opening / closing door 20 to which the rotary damper according to the fourth embodiment of the present invention is applied. A case where the main rotary damper of FIG. 11 is used for the opening / closing door 20 of an audio device will be described. In FIG. 12, the opening / closing door 20 of the audio device is designed to be opened / closed in the arrow G direction and the arrow H direction about the opening / closing shaft 22, and when the eject button (not shown) is operated, the arrow is generated by the unwinding force of the mainspring 13. It is opened in the G direction. Door 2
At 0, a fan-shaped gear 23 centering on the opening / closing shaft 22 is attached, and the fan-shaped gear 23 meshes with the gear 14 of the rotary damper. Although not shown, at least one of the case body 3a and the holding cylinder 10 of the rotary damper is attached to the audio device body 21.

Next, a specific operation of the opening / closing door 20 will be described. When the opening / closing door 20 opens due to the unwinding force of the mainspring 13 (direction of arrow G), the gear 14 rotates counterclockwise (direction of arrow I). At this time, since the blade portion 4 in the rotary damper also rotates in the direction of the acute angle portion 4d (arrow C direction) of the triangular cross section, the braking torque by the damper is large, the opening speed of the opening / closing door 20 is moderated, and the opening is gentle. It will work. On the other hand, when the mainspring 13 is rolled up from one end to close the opening / closing door 20 (direction of arrow H), the gear 14
Is rotated clockwise (direction of arrow J). At this time, the blade portion 4 in the rotary damper is also at the same time the base 4e of the triangular cross section.
Since it rotates in the direction (direction of arrow D), the braking torque by the damper is small, and the opening / closing door 20 can be quickly closed with a small force.

When the rotary damper according to the fourth embodiment is applied to the opening / closing door of the audio equipment as described above, the following effects can be obtained. When the opening / closing door 20 is opened by the unwinding force of the mainspring 13, the door is opened gently. On the other hand, when the mainspring 13 is rolled up and the opening / closing door 20 is closed, it can be quickly performed with a small force.

Further, since the closing operation of the opening / closing door 20 of the audio equipment is performed by human power, there is a large variation in the force. For example, if a strong person tries to close the door at a high speed, the load on the damper increases in proportion to the speed, and an excessive load is added to the damper.
According to the present rotary damper, since the braking torque can be reduced, the load applied to the damper is also reduced, and it is possible to prevent damage or the like.

FIG. 13 is a perspective view of a portable electronic device to which the rotary damper according to the fourth embodiment of the present invention is applied.

This portable electronic device is composed of an electronic device main body 32 having an input section 30, a display section 31, and a processing section which does not display, and a cover 33 which covers the input section 30 as a driving body. Here, the input unit and the display unit may be driven.

The main rotary damper shown in FIG. 11 is incorporated in the electronic equipment main body 32. Further, the cover 33 is provided with a rack 34 so as to mesh with the gear 14. Here, the sliding drive operation of the cover 33 is realized by the movement of the gear 14 and the rack 34. Further, in FIG. 13, the rotation axis of the gear 14 is arranged perpendicular to the surface of the cover 33, but the rotation axis of the gear may be arranged parallel to the cover surface. Further, the rack 34 may be attached to the electronic device main body 32, and the rotary damper of FIG. 11 may be attached to the cover 33. Further, not only the rack and the gear but also the pulley and the belt may be used.

The cover 33 is slidably attached to the electronic equipment main body 32 and can be operated in the arrow V direction and the arrow W direction. When the cover 33 operates in the arrow V direction, the cover is closed. And It is assumed that the cover opens when it moves in the direction of arrow W. Also, cover 3
When 3 moves in the direction of arrow V and reaches the drive limit, the stopper 35 prevents the cover 33 from popping out.

Next, the operation of the portable electronic device will be specifically described. As shown in FIG. 13, the cover 3 is manually loaded.
When 3 is closed (direction of arrow V), the linear motion of the cover 33 is converted into rotational motion via the rack 34, and the gear 14 rotates clockwise (direction of arrow X). This rotation is transmitted to the mainspring 13, and energy is accumulated in the mainspring 13. At this time, since the blades 4 in the rotary damper also rotate in the direction of the base 4e (arrow D direction) of the triangular cross section, the braking torque by the damper is small and the cover 33 can be closed quickly with a small force.

When the cover 33 is completely closed, there is a switch mechanism (not shown) inside the electronic device main body 32, and the stopper 35 of this switch mechanism and the cover 33 mesh with each other.
The cover 33 is prevented from opening due to the rewinding of the mainspring 13.

When the cover 33 is opened (in the direction of arrow W), the stopper 35 is interlocked by pushing the switch 36 provided in the switch mechanism, the cover 33 is disengaged from the stopper 35, and at the same time, the energy stored in the mainspring 13 is stored. As a result, the gear 14 rotates counterclockwise (arrow Y), is transmitted to the cover 33 via the rack 34, and automatically opens with the mainspring energy. At this time, since the blade portion 4 in the rotary damper also rotates in the direction of the acute angle portion 4d (arrow C direction) of the triangular cross section, the braking torque by the damper is large, the opening speed of the cover 33 is moderated, and the opening operation is gentle. Becomes

As described above, when the rotary damper of the fourth embodiment is applied to the driving body of the portable electronic device, the same effect as when applied to the audio device can be obtained.

As the application example of the fourth embodiment, the opening / closing lid of the audio device and the portable electronic device have been described, but the present invention is not limited to this and can be applied to various devices.

[0062]

As described above, according to the present invention, the following excellent effects can be obtained as compared with the conventional rotary damper.

By only deforming the braking plate of the conventional general rotary damper, it is possible to generate different braking torque depending on the rotation direction. Further, since the number of parts is small, the manufacturing is easy and the durability is excellent. Further, since it has a simple structure, it is easy to handle during assembly and disassembly.

[Brief description of drawings]

FIG. 1 is a perspective view showing a structure of a rotary damper according to a first embodiment of the present invention.

FIG. 2 is a diagram showing streamlines of viscous fluid in the case when the blade portion of the rotary damper of the embodiment is rotated in the end surface R direction (arrow A direction) of the trapezoidal cross section.

FIG. 3 is a diagram showing streamlines of viscous fluid in the case when the blade portion of the rotary damper of the embodiment is rotated in the end face L direction (arrow B direction) of the trapezoidal cross section.

FIG. 4 is a functional explanatory view of the rotary damper according to the first to third embodiments of the present invention.

FIG. 5 is a perspective view showing a structure of a rotary damper according to a second embodiment of the present invention.

FIG. 6 is a diagram showing streamlines of the viscous fluid in the case when the blade portion of the rotary damper of the embodiment is rotated in the direction of the acute angle (arrow C direction) of the triangular cross section.

FIG. 7 is a diagram showing streamlines of a viscous fluid in the case when the blade portion of the rotary damper of the embodiment is rotated in the base direction (arrow D direction) of the triangular cross section.

FIG. 8 is a perspective view showing a structure of a rotary damper according to a third embodiment of the present invention.

FIG. 9 is a diagram showing streamlines of viscous fluid in the case when the blade portion of the rotary damper of the embodiment is rotated in the direction of the acute angle section (direction of arrow E).

FIG. 10 is a diagram showing streamlines of the viscous fluid in the case when the blades of the rotary damper of the embodiment rotate in the direction of the bottom of the cross section (direction of arrow F).

FIG. 11 is a sectional view of a rotary damper according to a fourth embodiment of the present invention.

FIG. 12 is a side view of an opening / closing door of an audio device to which a rotary damper according to a fourth embodiment of the present invention is applied.

FIG. 13 is a perspective view of a portable electronic device to which a rotary damper according to a fourth embodiment of the present invention is applied.

FIG. 14 is a perspective view showing the structure of an example of a conventional rotary damper.

[Explanation of symbols]

1 rotation axis 2 Viscous fluid 3 cases 3a Case body 3b case lid 4 wings 4a End surface R 4b End face L 4c slope 4d sharp corner 4e Bottom 4f flat section 10 holding cylinder 11 tube lid 12 true 12a engaging part 13 spring 14 gears 20 open / close door 21 Audio equipment body 22 Open / close shaft 23 fan gear 30 Input section 31 Display 32 Electronic device body 33 cover 34 racks 35 Stopper 36 switch

Claims (5)

[Claims] 1. A rotary damper composed of a brake plate rotatably housed in a case filled with fluid, and a rotary shaft that is engaged with the brake plate or integrally formed with the brake plate, wherein the brake plate. Has at least one blade portion extending in the peripheral direction from the rotating shaft, and the blade portion has an end surface R that receives a fluid load when the braking plate rotates in one direction,
It has an end face L that receives a fluid load when it is rotated in the opposite direction, the end face R and the end face L have different thicknesses, and each end face is formed by a flat surface, a curved surface, or a combination of both. The characteristic rotary damper. 2. The rotary damper according to claim 1, wherein the thickness of one of the two end faces of the blade portion is close to zero. 3. The rotation according to claim 1, wherein a portion of the blade portion is provided with a flat portion that substantially matches the total thickness of the blade portion and faces the case upper surface or the case lower surface in parallel. damper. 4. A rotary damper according to claim 1, wherein the rotary damper is combined with an energy storage member. 5. The device according to claim 1, wherein the rotary damper is used.