JP2554574B2 - Free fall prevention hinge - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a free fall preventing hinge used for a rotating portion of a second portion to be fixed and a first portion to be rotated and raised with respect to the second portion.

[0002]

2. Description of the Related Art There are many devices such as a cover of a copying machine and a display of a laptop personal computer which are opened and closed with respect to a fixed main body. In such a device, it is a normal operation that the cover is opened and stopped to be used, and then the user manually closes the cover after use. In this case, in the conventional device, it is general to use the force of a spring or the like and the frictional force for such an opening / closing portion. For this reason, it is difficult to set the cover at any desired open position, and because the static friction force and the dynamic friction force are different, the opening and closing torque of the cover is unstable, and it is difficult to open and close the cover smoothly. there were. Further, such conventional devices have generally been large in shape.

[0003]

SUMMARY OF THE INVENTION The present invention solves the above problems in the prior art, has a small shape, facilitates the setting of the position of the second portion, and has a free fall prevention function which can be opened and closed smoothly. It is an object to provide a hinge.

[0004]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention provides a free fall used in a rotating part of a fixed second part and a first part which is rotated and raised with respect to the second part. The prevention hinge has an inner rotating body, an outer ring, rollers, a supporting means, a biasing means, and a movement stopping means, and the inner rotating body has a single-leaf rotating twin around its central axis. A monotonous rotating hyperboloid about the central axis so as to form a raceway between the inner raceway surface and the inner raceway surface and a first torque transmitting portion coupled to the first portion. And a second torque transmitting portion coupled to the second portion, the roller has a cylindrical rolling surface, and the center line of the roller in the race is a cross section including the central axis. Tilted at a certain angle from the Several rollers are provided, and the surfaces of the rollers linearly contact the inner raceway surface and the outer ring raceway surface, and the supporting means is fixed to the second portion to move the inner rotating body in the central axis direction. It is rotatably supported at a fixed position, the biasing means biases the outer ring in the direction of the central axis and in the direction of narrowing the space between the raceways, and the movement stopping means includes a bearing. The movement of the outer ring in the direction of narrowing the track spacing is stopped at a predetermined position, and the predetermined position is set to a position that gives a rotational resistance larger than the rotational moment due to the weight of the first portion. And

[0005]

[Operation] Since the inner rotating body is rotatably supported at a fixed position in the central axis direction by the supporting means, and this supporting means is fixed to the second portion, the inner rotating body is in the central axis direction with respect to the second portion. Can be rotated at a fixed position. The inner rotating body rotates at the same time as the first portion because the first torque transmitting portion is coupled to the first portion. On the other hand, the outer ring is provided with the second torque transmission portion, which is coupled to the second portion, so that the rotation is restrained by the fixed second portion. As a result, the rotation of the first portion with respect to the second portion is replaced by the rotation between the inner rotating body and the outer ring.

Next, the respective surfaces of the inner rotating body and the outer ring facing each other are made into single-leaf rotating hyperboloids, and a plurality of rollers are inclined in a raceway formed on both sides to make line contact with both raceway surfaces. However, since the outer ring is urged by the urging means in the direction of narrowing the raceway distance, an action as a rolling bearing clutch occurs between the inner rotating body and the outer ring. That is, for example, when the input torque is transmitted to the inner rotary body through the first torque transmission portion by opening and closing the first portion and the inner rotary body rotates in one direction, the rollers move on both raceway surfaces of the inner rotary body and the outer ring ( Guided by the inner and outer raceways) and revolve while rotating on their respective upper portions, the inclination causes them to move in opposite directions in the central axis direction with respect to the inner rotating body and the outer ring. As a result, due to the relationship between the roller inclination direction and the rotation direction of the rotating body,
A separation force or a drawing force is generated in the central axis direction between the inner rotating body and the outer ring. Since the inner rotor is fixed in its axial position, the outer ring moves in the axial direction, and when a separation force is generated between them, the orbital interval increases and free rotation is possible between the inner rotor and the outer ring. When a pulling force is generated, the raceway space is narrowed and the inner rotating body and the outer ring are clutched via rollers.
Therefore, when the rotation in one direction is selected as the free rotation side, the reverse rotation becomes the clutch. This clutch operation is instantaneously and reliably performed because the biasing means biases the outer ring in the clutch direction. As a result, the first portion is free to rotate in one direction with respect to the second portion and is clutched in the opposite direction. When the clutch is engaged, the rotation of the rotating portion is limited. However, if a torque equal to or higher than the clutch torque is applied to the rotating portion, the rotating torque can be rotated while the clutch torque becomes a rotational resistance.

Next, the clutch torque is initially given as a torque corresponding to the urging force at the same time as the reverse rotation when the outer wheel is pushed by the urging means. And
When the inner rotating body and the outer ring rotate relative to each other and a twist angle is generated between them, the outer ring advances in the direction of the central axis, and the track spacing becomes narrower correspondingly, so the clutch torque is the twist angle and therefore the amount of movement of the outer ring. Grows in size. Here, according to the present invention, since a bearing is provided as a movement stopping means for stopping the movement of the outer ring, and the movement of the outer ring in the direction of narrowing the track interval is stopped at a predetermined position via this bearing,
Since the outer ring is not twisted and moves further, the clutch torque generated at the position of the outer ring becomes the maximum clutch torque. Then, since the predetermined stop position is set to a position that gives a rotation resistance, that is, a clutch torque larger than the rotation moment due to the weight of the first portion, the first portion is lifted on the free rotation side to rotate the rotating portion, Even if a part is in a free state, the first part will not drop due to the moment due to its own weight. Such a predetermined position can be obtained by calculation or experiment. Further, the position may be adjustable. On the other hand, if a torque equal to or higher than the clutch torque is applied to the first portion, it can be moved in the falling direction. Therefore,
Position where the first part is lifted or moved downward,
The first part can be set at any position.

In this case, such a clutch torque is
Since it is obtained by the action of the rolling friction and the axial sliding friction of the rollers due to the minute deformation between the rollers and the inner rotating body and the outer ring, there is no variation and the stability is obtained. Since the outer ring is stopped moving by the bearing, the outer ring is smoothly rotated, and accurate and stable rotation resistance is maintained. Furthermore, according to such a free fall prevention hinge,
Since the structure has a rolling bearing shape, the allowable surface pressure is high and a large sliding portion is not required, so that the shape can be reduced.

[0009]

[Example] Fig. 1 shows a schematic structure of a hinge with free fall prevention according to an embodiment. The device of the present embodiment is, as an example of a rotating part of a fixed second part and a first part which is rotated and raised with respect to the fixed second part, as a first part, a cover 100 with a display of a personal computer or a word processor, and a second part. It can be used for the rotating part between its body 200 as a part. The present apparatus includes an inner shaft 1 serving as an inner rotating body, an outer ring 2, rollers 3, a housing 4 and a supporting bearing 5 serving as supporting means, and a preload spring 6 serving as urging means.
And a thrust bearing 7 as a movement stopping means.
The inner shaft 1 includes an inner raceway surface 1a forming a single-leaf rotation hyperboloid around the central axis 1b and a cover mounting portion 1c as a first torque transmitting portion coupled to the cover 100, and is fixed to the main body 200. It is rotatably supported at a fixed position in the direction of the central axis 1b by the housing 4 and the support bearing 5 which are formed. In the present embodiment, the inner rotating body is integrally formed as the inner shaft 1 as described above, but each component is formed as a separate body, for example, the raceway surface portion and the shaft are formed as separate bodies, and these components are joined together. Of course, it can be formed by.

The outer ring 2 has a raceway 8 between itself and the inner raceway surface 1a.
Is provided with an outer ring raceway surface 2a forming a single-leaf rotation hyperboloid around the central axis 1b so as to form a preload spring 6 as a second torque transmitting portion coupled to the main body 200. That is, in this embodiment, the preload spring 6 also serves as a torque transmitting means as described later, and the torque is transmitted between the preload spring 6 and the main body 200 via the housing 4. ing. However, as the second torque transmission portion, another type such as a ball spline or a torque transmission pin may be used.

As shown in FIG. 2, the roller 3 has a cylindrical rolling surface, and the raceway 8 is inclined with the center line of the roller 3 from the cross section including the central axis 1b by a constant angle β (for example, 15 °). A plurality of them are arranged in the circumferential direction, and their surfaces are in linear contact with the inner raceway surface 1a and the outer ring raceway surface 2a. The rollers 3 are held in position by a retainer 9 so that the rollers 3 rotate smoothly without interfering with each other.

Raceways 1a and 2a of the inner shaft 1 and the outer ring 2
Is a single-plane hyperboloid of revolution obtained by rotating the hyperbola expressed by the following equation around the center line 1b so as to linearly contact the roller 3 as described above. yi ² / ai ² -xi ² / bi ² = 1 yo ² / ao ² -xo ² / bo ² = 1 Here, x _i and x _o are the centers from the origin of the inner raceway surface 1a and the outer raceway surface 2a, respectively. The distance in the direction of line 1b, y _i ,
_yo is the distance from the center line 1b of the inner ring raceway surface 1a and the outer ring raceway surface 2a in an arbitrary section including the center line 1b, and ai, bi, ao, and bo are constants. Now, assuming that the distance from the center line 1b to the center of the track 4 on the reference surface on the small diameter side of the inner and outer rings (origin plane of the hyperbola) is F, the radius of the roller 3 is r, and the inclination angle is β, F = 9, r = 1.5, β = 15
When the calculation in the case of ° is performed (the calculation is omitted because it is complicated), the values of ai, bi, ao, and bo are about 7.
5, 30.1, 10.5, and 37, giving the shape of the single-blade hyperboloid of the inner and outer raceway surfaces.

The preload spring 6 as the urging means and torque transmitting means has a structure as shown in FIG. The preload spring 6 is made of an elastic body, and transmits the urging force and the torque. The protrusions 6 on the outer ring 2 side and the housing 4 side, respectively.
a and 6b, the tip surfaces and one side surface of the convex portions 6a and 6b are in pressure contact with the front surface and one side surface of the concave portions 2b and 4a of the outer ring 2 and the housing 4, respectively, and the biasing force and torque are transmitted between them. It is supposed to be done. The biasing force acts in a direction to reduce the track interval. The illustration shows the preload spring 6
However, thrust T ₁ , T ₂ and torques M ₁ , M ₂ (T ₁ , T ₂ and M ₁ from the outer ring 2 and the housing 4 as biasing forces.
And M ₂ are in the opposite directions and have the same size) and are deformed.

The thrust bearing 7 stops at a predetermined position the movement of the outer ring 2 in the direction in which the distance between the raceways 8 is narrowed in the direction of the central axis 1b (right to left in the figure). This operation is performed via the collar 10. The predetermined position of the bearing 7 is set so that the maximum clutch torque when the movement of the outer ring 2 is stopped becomes equal to the rotational resistance to be applied. This rotation resistance is
The resistance is sufficient to maintain the cover 100 in an open state against the moment due to the weight of the cover 100 that is applied to the cover mounting portion 1c, and is a resistance that provides an appropriate strength when the cover 100 is closed. is there. It should be noted that the predetermined position for imparting such rotation resistance can be adjusted by a method such as mounting the bearing 7 to the inner shaft 1 with a screw. With the above configuration, the operation of this hinge is as follows. When the cover 100 is lifted and closed from the opened state, the cover 3 is rotated in the direction of the arrow A and the inner shaft 1 is rotated in that direction, so that the rollers 3 move the inner raceway surface 1a and the outer ring. It is guided by the raceway surface 2a and revolves on its own axis while revolving, and a pulling force in the direction of the central axis 1b is generated between the inner shaft 1 and the outer ring 2. Since the inner shaft 1 is fixed at the position in the direction of the central axis 1b, the outer ring 2 moves from the right to the left in the drawing, the track interval is narrowed, and the urging force of the preload spring 6 also acts.
The inner shaft 1 and the outer ring 2 are clutched via rollers 3. On the other hand, since the outer ring 2 is coupled to the main body 200 via the preload spring 6 and the housing 4, the cover 100 and the main body 200 are clutched. This operation is performed at the same time as the rotation of the inner shaft 1 in the direction of arrow A and reliably because the biasing force of the preload spring 6 acts.

When the inner shaft 1 and the outer ring 2 are clutched in this way, the rotation of the rotating portion is restricted. However, if a torque greater than the clutch torque is applied to the rotating portion,
Rotation of the rotating part becomes possible while the amount of clutch torque becomes rotational resistance. This clutch torque is
It is initially given as a torque corresponding to the biasing force of the preload spring 6. Then, when a large torque is applied to the cover mounting portion 1c through the cover 100, the inner shaft 1 and the outer ring 2 are further rotated relative to each other to increase the twist angle therebetween, and the outer ring 2 is moved rightward in the direction of the central axis 1b. From the left to the left, the track spacing becomes narrower correspondingly, and the clutch torque becomes larger corresponding to the twist angle and hence the amount of movement of the outer ring. The clutch torque M is M = Aδ ^3/2 (M = A′α ^3/2 ) where δ (which corresponds to the twist angle α) is the amount of advance of the outer wheel after clutching. Note that A and A ′ are torsion spring constants, which are values determined for each device, and can be easily calculated or calculated.

Since the rotational resistance moment can be calculated in this manner, the free fall of the cover 100 is prevented, and at the time of closing the cover 100, the optimum maximum rotational resistance moment is given so that δ of the above equation is given. By calculating the value, the predetermined position in the direction of the central axis 1b of the bearing 7, which is the movement stopping means of the outer ring 2, is determined. FIG. 4 shows an example of a clutch torque curve with respect to the movement amount δ or the twist amount α of the outer ring 2. As shown, in order to obtain the torque M ₁ ,
The amount of movement of the outer ring 2 is δ ₁ , and the bearing 7 is set at that position.

When the cover 100 is opened and the cover mounting portion 1c is rotated in the direction opposite to the arrow A, the operation is opposite to that described above, and the inner shaft 1 and the outer ring 2 rotate freely without being clutched, 100 can be opened lightly.

[0018]

As described above, according to the present invention, it is possible to easily set the position of the second portion, stably provide a constant rotational resistance, and to downsize the device.

[Brief description of drawings]

FIG. 1 is a sectional view of a hinge with free fall prevention according to an embodiment.

FIG. 2 is a perspective view showing the arrangement of the rollers.

FIG. 3 is a perspective view of the preload spring.

FIG. 4 is a curve diagram showing a relationship between a twist angle or an outer ring displacement and a clutch torque.

[Explanation of symbols]

 1 inner shaft (inner rotating body) 1a inner shaft raceway surface (inner raceway surface) 1b center shaft 1c cover mounting portion (first torque transmitting portion) 2 outer ring 2a outer ring raceway surface 3 roller 4 housing (supporting means) 5 support bearing ( Supporting means) 6 Preload spring (biasing means, second torque transmitting section) 7 Thrust bearing (moving stopping means) 8 Track 100 Cover (first part) 200 Main body (second part)

Claims (1)

(57) [Claims] 1. A free fall preventing hinge used for a rotating part of a fixed second part and a first part which is rotated and raised with respect to the second part, wherein an inner rotating body, an outer ring, and A roller, a supporting means, a biasing means, and a movement stopping means, wherein the inner rotating body is connected to the inner raceway surface forming a single-leaf rotating hyperboloid about its central axis and the first portion. A first torque transmitting portion, wherein the outer ring is coupled to the second portion and the outer ring raceway surface forming a single-leaf rotation hyperboloid about the central axis so as to form a raceway with the inner raceway surface. And a plurality of rollers in the circumferential direction of the raceway, wherein the rolling surface of the roller has a cylindrical shape, and the center line of the roller in the raceway is inclined at a constant angle from a cross section including the central axis. The inner raceway surface and the surface of the roller In linear contact with the outer ring raceway surface, the supporting means is fixed to the second portion and rotatably supports the inner rotating body at a constant position in the central axis direction, and the biasing means is The outer ring is urged in the direction of the central axis in the direction of narrowing the space between the raceways, and the movement stopping means includes a bearing to move the outer ring in the direction of narrowing the space between the raceways. A hinge with free fall prevention, characterized in that the hinge is stopped at a predetermined position, and the predetermined position is a position that gives a rotation resistance larger than a rotation moment due to the weight of the first portion.