JPH04337136A - Rotary damper - Google Patents

Abstract

PURPOSE:To provide a rotary damper to attain action of adequate braking power, and small in size and light in weight. CONSTITUTION:A rotational control member 4 is formed by providing a disk part 41 for closing an opening part of a casing 2, cylindrical part 42 protrusively provided in this disk part 41, partitioning part 43 protrusively provided in the periphery of this cylindrical part 42 by providing a cavity part 43a in the inside and also valve holes 43d, 43e in wall parts 43b, 43c and a valve member 44 arranged in the cavity part 43a of this partitioning part 43, and the casing 2 is provided with the rotational control member 4 in it. A fluid chamber 27, formed of the concerned disk part 41 and peripheral and bottom wall parts of the casing 2, is filled with damper fluid 6. A grooved orifice 5 is formed further in the internal periphery of the casing 2 and also arranging an accumulator 7 in an empty chamber 28 connected to the fluid chamber 27. In the case of closing an object of rotation, the valve holes 43d, 43e are closed by the valve member 44 to generate predetermined braking force to act.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary damper for absorbing a falling impact caused by free rotation of a rotating object.

0002

[Prior Art] Generally, pianos, record players,
The opening/closing lids of portable computers, copy machines, and other office equipment, opening/closing lids of pianos, etc., toilet seats and toilet lids of Western-style toilets, etc. have one base supported by a rotating shaft and the other end set as a free end. It is provided so as to be rotatable in the vertical direction within a rotation angle range of approximately 120° to 120°. When closing such a rotating object, such as a toilet lid or a toilet seat of a Western-style toilet bowl, the lid or the like becomes a free-falling rotating object. At this time, if you do not close it with your hand until the end, there is an inconvenience that it will collide at the final point of the closing rotation, producing a large impact sound and causing damage. In view of this inconvenience, rotary dampers having a structure in which the rotational torque is reduced by utilizing the viscous resistance of a liquid such as grease disposed in the gap between the double cylinders have been widely used.

0003

[Problems to be Solved by the Invention] However, among the above-mentioned computers, a display device is built into a rotating lid that opens and closes, such as a so-called laptop computer, which opens and closes (folding type). Because of this, it is heavy, and there is a problem in that it is not possible to exert a predetermined resistance force using grease or the like. Moreover, since this type of personal computer is required to be small and lightweight, the damper must also be small and lightweight. However, if a damper using grease or a spring is used to exert a predetermined resistance force, the damper will also have to be large, which poses a problem that it cannot be applied to these personal computers and the like.

The present invention has been made to solve the above-mentioned problems, and it is possible to apply an appropriate braking force even when the rotating lid of an open/close type personal computer or the like has a predetermined weight. It is an object of the present invention to provide a rotary damper that is small and lightweight and does not increase the size or weight of the entire device such as an open/close type personal computer.

[0005]

[Means for Solving the Problems] In order to achieve the above object, the rotary damper of the present invention has a rotary shaft holding hole formed approximately in the center, and a circular damper that closes the opening of the approximately cylindrical casing. a plate part, a cylindrical part protruding from the disc part, a hollow part protruding from the outer periphery of the cylindrical part for housing a valve therein, and a wall part facing each other through the hollow part. A partition wall portion having a valve hole provided so as not to face each other directly, and a hole portion disposed within the cavity portion and capable of communicating with a valve hole provided in one of the wall portions forming the partition wall portion. A plate-shaped valve member is rotatably loaded into a casing, and a liquid chamber can be formed by the disk part and the peripheral wall and bottom wall of the casing, and the liquid chamber can be formed by a partition wall. a rotation control member that divides the liquid into two chambers, an orifice carved into the bottom or inner peripheral surface of the casing and provided to communicate the two liquid chambers, and a damper liquid filled in the liquid chamber. An accumulator disposed in a cavity communicating with the liquid chamber within the casing.

[0006]

[Operation] When the opening/closing lid or the like is opened from the closed state, the rotation control member also rotates together with the rotation shaft. At this time, the valve member is pressed against one wall of the partition wall formed in the rotation control member, and the hole formed in the valve member and the valve hole formed in the wall communicate with each other. The damper liquid flows from one liquid chamber to the other liquid chamber through a valve hole formed in the wall of the damper liquid. Therefore, the resistance of the damper liquid that the partition wall part receives during opening is small, and the opening operation can be performed easily and smoothly. On the other hand, when the valve member is closed, the valve member is pressed against the other wall portion in the opposite manner to the above, so that the valve hole formed in the wall portion is closed by the valve member. Therefore, since the damper liquid flows from the other liquid chamber into one liquid chamber through the orifice, the rotation control member, rotation shaft, and opening/closing lid are Rotate slowly in the closing direction.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be explained in more detail below based on embodiments shown in the drawings. In the figure, reference numeral 1 indicates a rotary damper according to this embodiment, which includes a casing 2 and a rotation control member 4.
, an orifice 5, a damper liquid 6, etc.

The casing 2 is formed into a substantially cylindrical shape with a bottom, and a lid member 20 is attached to an opening 21 at one end. Also,
Inside the casing 2, a convex portion 22a that protrudes inward at approximately the center of the bottom wall portion 22, and a substantially semi-tubular bearing wall portion 24 that protrudes around the convex portion 22a are formed. A recess 42a formed at the rear end of a cylindrical portion 42 of a rotation control member 4, which will be described later, engages with the portion 22a, and the cylindrical portion 42 is supported in contact with the bearing wall 24. Further, at both ends of the bearing wall 24, a rotation range of the rotation control member 4 is set to 90°.
Regulation wall part 2 for regulating in the range of about 120 degrees
5 and 26 are provided. One of the gaps formed by the peripheral wall and bottom wall of the casing 2 and the disc part 41 of the rotation control member 4 and partitioned by the regulating walls 25 and 26 serves as the liquid chamber 27, and the other serves as a vacant space 28 for accumulator installation. Note that the liquid chamber 27 and the empty chamber 28 are communicated with each other through a communication hole 29 formed in the regulating wall portion 25. Reference numeral 30 denotes a damper liquid injection hole formed in the peripheral wall of the casing, and the damper liquid 6 is injected through this injection hole 30. 31 and 32 are set screws and packing for closing the damper liquid injection hole 30. Further, 3 is a click mechanism composed of a ball part 3a and a spring part 3b disposed inside the injection hole 30 and supporting the ball part 3a. The ball portion 3a engages with a recess 42a formed around the cylindrical portion 42 to regulate the opening angle.

The rotation control member 4 is composed of a disk portion 41, a cylindrical portion 42, and a partition wall portion 43, as shown in FIGS. 3 to 5. The disc part 41 is formed to have approximately the same diameter as the inner diameter of the casing 2, and when loaded into the casing 2, it closes the opening 21 and seals the damper liquid 6 filled in the liquid chamber 27 and the empty space 28. to hold. In addition, this disk portion 41
In order to fix a rotating shaft of an opening/closing lid (not shown), etc., a substantially elliptical rotating shaft holding hole 41a is bored. Note that a sealing packing 8 is provided between the disc portion 41 and the lid member 20.
is installed.

The cylindrical portion 42 projects from the disc portion 41, and as described above, is supported in contact with the bearing wall portion 24, and
The concave portion 42a formed at the rear end corresponds to the convex portion 22 of the casing 2.
a and is held freely rotatable. Further, 42b is a hollow portion, which is formed in a substantially elliptical shape and is communicated with the rotating shaft holding hole 41a of the disc portion 41 to fix and hold a rotating shaft (not shown).

A cavity 43a is formed inside the partition wall 43 along its longitudinal direction, and the cavity 43a
Valve holes 43d and 43e, which do not face each other directly, are formed in the wall portions 43b and 43c, which face each other through the valve holes 43d and 43e, respectively. The shape and size of the valve holes 43d and 43e are not particularly limited as long as they are formed so that they do not face each other directly, for example, as shown in FIGS. 4 and 5, A substantially square valve hole 43d may be formed in the substantially central portion of the wall portion 43b, and substantially square valve holes 43e, 43e may be formed near both ends of the other wall portion 43c. Note that the liquid chamber 27 formed in the casing 2 is divided into two, a first liquid chamber 27a and a second liquid chamber 27b, with this partition wall portion 43 as a boundary (see FIG. 1).

In the cavity 43a of the partition wall 43, as shown in FIG.
, as shown in FIG. 7, when the rotation control member 4 of the walls 43b and 43c is rotated in the opening direction, it is located at a position communicating with the valve hole 43d or 43e of the wall on the rear side with respect to the opening direction. A plate-shaped valve member 44 having a hole 44a formed therein.
is stored and maintained. In this embodiment, it is formed so as to communicate with a valve hole 43d formed in the wall portion 43b. In addition, the thickness is determined by the width of the cavity 43a, that is, the one wall portion 43b.
and the other wall portion 43c. That is, for example, the valve member 44
The valve member 44 is formed to have a thickness such that a gap is created between the valve member 44 and the other wall portion 43c when the valve member 44 is pressed against the wall portion 3b.

As shown in FIGS. 1 and 2, the orifice 5 is arranged in a casing so that a first liquid chamber 27a and a second liquid chamber 27b, which are partitioned by the partition wall 43 of the rotation control member 4, can communicate with each other. The bottom wall portion 22 of No. 2 is carved in a substantially arc shape with a predetermined width. Note that instead of being provided on the bottom wall portion 22, it may be carved on the inner surface of the peripheral wall portion. Here, the length of this orifice 5 is the same as that of the first liquid chamber 2, as shown in the drawing.
If 7a is carved only halfway, the rotation control member 4
When it passes through the orifice 5, the rotation becomes immobile. Therefore, in this embodiment, there is a slight gap (not shown) between the inner circumference of the casing 2 and the partition wall portion 43 of the rotation control member 4.
is formed to prevent such harmful effects. It goes without saying that the orifice 5 may have a length that spans the entire first liquid chamber 27a.

The accumulator 7 is formed from a single-foam flexible rubber member or the like, and has a cavity 2 formed in the casing 2.
8 is loaded.

Next, the operation of the rotary damper 1 of this embodiment will be explained. First, when a rotating lid (not shown) of a laptop computer or the like is opened, a rotating shaft (not shown) and rotation control member 4 rotate in the direction of arrow X in FIG. At this time, the valve member 44 is pressed against one wall 43b of the partition wall 43, and the hole 44a of the valve member 44 and the wall 43b
The valve hole 43d communicates with the valve hole 43d. As a result, as the rotary lid is opened, the damper liquid 6 flows through the hole 44a and the valve hole 43d.
It moves from the second liquid chamber 27b to the first liquid chamber 27a through the valve hole 43e of the other wall 43c and the orifice 5. Therefore, when opening, the rotary lid etc. can smoothly open without receiving much resistance.

On the other hand, the rotary lid is moved in the closing direction, that is, as shown in FIG.
When the valve member 44 is rotated in the direction of arrow Y, the damper liquid 6 presses the valve member 44 against the other wall 43c of the partition wall 43. As a result, the valve hole 43e of the other wall portion 43c is closed by the valve member 44. Therefore, the damper liquid 6 moves from the first liquid chamber 27a to the second liquid chamber 27b through the orifice 5, the casing 2, and the rotation control member 4.
Since this is done through the gap formed between the damper liquid 6 and the partition wall 43, a large damping force acts due to the dynamic pressure resistance and viscous resistance generated when the damper liquid 6 passes through the orifice 5. Incidentally, when the damper liquid 6 thermally expands, the accumulator 7 contracts and stores the damper liquid 6 into the cavity 28 through the communication hole 29, thereby preventing leakage of the damper liquid 6. Furthermore, by forming the cavity 28 for arranging the accumulator 7, the peripheral wall of the casing 2 forming the liquid chamber 27 and the peripheral wall of the casing 2 forming the cavity 28 are formed to have approximately uniform thickness. can do. Therefore, when the casing 2 is molded using a resin material, it is possible to prevent so-called sink marks from occurring.

[0017]

[Effects of the Invention] According to the rotary damper of the present invention, the rotation control member rotates in the liquid filled in the casing even if the lid is heavy and a large torque is applied during closing rotation. Since the structure is such that the rotational movement is slowed down by the rotation, it is possible to reliably absorb the impact etc. at the final time of the closing rotation of the rotary lid. In addition, the rotation control member is not designed to absorb shock by moving in the longitudinal direction of the casing, but rather has a structure in which it can exert a predetermined resistance by rotating.
Weight reduction can be achieved.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing one embodiment of a rotary damper according to the present invention.

FIG. 2 is a longitudinal sectional view of the same embodiment.

FIG. 3 is a front view showing the rotation control member used in the same example.

FIG. 4 is a side view showing the rotation control member used in the same example.

FIG. 5 is a rear view showing the rotation control member used in the same example.

FIG. 6 is a front view showing the valve member used in the same example.

FIG. 7 is a side view showing the valve member used in the same example.

[Explanation of symbols]

1 Rotating damper 2 Casing 27 Liquid chamber 28 Vacancy 3 Click mechanism 4 Rotation control member 41 Disc part 42 Cylinder part 43 Partition wall part 43a Cavity part 43b Wall part 43c Wall part 43d Valve hole 43e Valve hole 44 Valve member 44a Hole 5 Orifice 6 Damper liquid 7 Accumulator

Claims (1)

[Claims] 1. A rotating shaft holding hole is formed in a substantially central portion of the casing, and a disk portion that closes an opening of a substantially cylindrical casing; a cylindrical portion protruding from the disk portion; a partition wall that protrudes from the outer periphery of the cylindrical portion, has an internal cavity for accommodating a valve, and has a valve hole provided so as not to directly face each of the opposing walls through the cavity; a plate-shaped valve member disposed within the cavity and having a hole that can communicate with a valve hole provided in one of the walls forming the partition wall;
A rotation control member that is rotatably loaded into a casing and that forms a liquid chamber by the disk portion and a peripheral wall and a bottom wall of the casing, and divides the liquid chamber into two chambers by a partition wall. an orifice carved in the bottom or inner peripheral surface of the casing and provided to communicate the two liquid chambers; a damper liquid filled in the liquid chamber; and a damper liquid that communicates with the liquid chamber within the casing. A rotary damper comprising: an accumulator disposed in a vacant chamber.