JPH056707Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a printed wiring board attaching/detaching structure for mounting a printed wiring board of an electronic device in a housing box and electrically connecting the printed wiring board to the outside.

[Prior Art] FIG. 5 is a side sectional view showing a conventional printed wiring board attachment/detachment structure, in which 1 is a guide plate, 2 is a guide rail provided inside the guide plate 1, and 3 is a guide rail provided at one end of the guide plate 1. 4 is a connector provided inside the back board 3; 5 is a guide portion formed by bending the other end of the guide plate 1; and 6 is a storage box having the above-described structure.

7 is a printed wiring board, 8 is a plug located at one end of the printed wiring board 7, 9 is an ejector, 10 is a projection of the ejector 9, 11 is a lever part of the ejector 9,
Reference numeral 12 indicates an action point at which the ejector 9 is rotatably attached to the corner of the end of the printed wiring board 7 in the direction opposite to the plug portion 8, and 13 indicates a lever portion 1 of the ejector 9.
1, and 14 indicates a fulcrum at the protrusion 10 of the ejector 9.

In order to mount the printed wiring board 7 in the storage box 6 with the conventional structure as described above, the upper and lower ends of the printed wiring board 7 are aligned with the guide rails 2 of the storage box 6, and the printed wiring board 7
into the storage box 6. At this time, printed wiring board 7
The tip of the plug part 8 hits the connector 4 located inside the back board 3 of the storage box 6, and the ejector 9
The protrusion 10 is included in the guide portion 5 on the opening side of the guide plate 1. This state is a state immediately before the pin arrangement etc. of the plug portion 8 are inserted into the connector 4.

In the above state, the lever portion 11 of the ejector 9
When the ejector 9 is rotated in the direction of the arrow a by applying a force to the force point 13 shown in FIG. It will be pushed further inside. Therefore, the plug portion 8 of the printed wiring board 7
The pin arrangement etc. are inserted into the connector 4 of the storage box 6, and the printed wiring board 7 is electrically connected to the connector 4. In this way, electrical connection with the outside is established.

A great deal of force is involved in the above-mentioned pin arrangement of the plug portion 8 and in the insertion and removal of the connector 4. For example, if the insertion force per pin is 200 g, a force of about 30 kg is required to insert a plug having 150 pins. In order to obtain this great force, conventionally, the ejector 9 constituting the lever portion 11 as described above is used.
The lever principle is applied, thereby making it possible to manually insert and remove the plug portion 8 and the connector 4.

Next, the ejector 9 will be further explained based on an enlarged side view of the ejector 9 shown in FIG.

As shown in FIG. 6, when a load F is applied to the force point 13 of the lever portion 11 of the ejector 9, a force P acts on the printed wiring board 7, and this force P inserts the aforementioned plug portion 8 into the connector 4. It becomes power.

Here, considering the ratio between the load F and the insertion force P, it is expressed as P=(I ₂ /I ₁ +Cosθ)·F. In addition, I ₁ is the length between the point of action 12 and the fulcrum 14, I ₂ is the length of the point of action 12 and the point of effort 13, and θ is the angle between the perpendicular to the point of action 12 and the straight line connecting the point of action 12 and the point of effort 13. show. As expressed by the above equation, the expansion rate of the insertion force P roughly depends on I ₂ /I ₁ . This is I ₁
This indicates that the insertion force P can be increased as the length of _I2 , that is, the length of the lever portion 11, is increased.

Since the number of pins of the above-mentioned plug portion 8 is likely to increase more and more in the future, the force required to insert and remove the plug portion 8 on the printed wiring board 7 continues to increase.

[Problem that the invention attempts to solve]

As described above, the conventional ejector 9 is rotated by the lever portion 11 to close the plug portion 8 of the printed wiring board 7.
is inserted into the connector 4 of the storage box 6,
There is a problem in that a space for movement of the lever part 11 is required, and this is due to the increase in the insertion and removal force between the plug part 8 and the connector 4 due to the increase in the number of pins of the plug part 8 described above. This problem is further exacerbated by the fact that _I2 relative to _I1 , that is, the lever portion 11 must be made longer. This is because the space for the external connection connector mounted near the ejector 9 on the printed wiring board 7 is reduced, and the route space for cable wiring is compressed, resulting in many problems and becoming a major obstacle in downsizing the device. It is.

Furthermore, as the force for inserting and removing the printed wiring board 7 increases, the force R generated at the fulcrum portion 14 of the protrusion 10 of the ejector 9 increases, as shown in FIG.
This force R becomes a bending stress near the base of the protrusion 10, so it may cause damage or destruction near the base of the protrusion 10.
In other words, there was a problem that the ejector 9 was damaged or destroyed.

Furthermore, because the conventional ejector 9 has a structure including a protrusion 10 and a lever part 11, the load required for inserting and removing the plug part 8 of the printed wiring board 7 and the connector 4 is reduced.
Since the stroke of the printed wiring board 7 is not constant, the required external force for the lever rotation angle of the ejector 9 changes rapidly. Referring to FIG. 4, which shows the relationship between the rotation angle of the ejector and the load, this state is clearly shown by a rapidly changing curve as shown by conventional curve A. In the figure, A is the insertion start position, B is the insertion end position, the vertical direction is the change in load, and the horizontal direction is the change in the ejector rotation angle. Such a large change in the required external force, that is, the load, with respect to the rotation angle of the ejector 9 poses a problem that reduces operability, for example, when pushing or pulling the lever portion 11 with one finger. This has also become a safety issue for the equipment.

The object of the present invention is to obtain a structure for attaching and detaching a printed wiring board using an ejector, which occupies less space, has a constant small load, is simple in structure, and has excellent strength.

[Means for solving problems]

In order to solve the above-mentioned problems, the present invention is designed to press the printed wiring board in order to insert the connecting part of the printed wiring board into the connector installed in the storage box when mounting the printed wiring board in the storage box. In the printed wiring board attachment/detachment structure having an ejector to be moved, a recess is formed in the edge of the printed wiring board near the end opposite to the plug part, and the ejector has a protrusion forming a spiral on the outer periphery of the shaft part. A spiral rotating body, a notch provided in a part of the spiral rotating body in the axial direction so as not to interfere with insertion and removal of a printed wiring board, and a notch provided at one end of the shaft to rotate the spiral rotating body. The rotating lever has an axis parallel to the insertion/extraction direction of the printed wiring board near the opening side of the storage box through which the printed wiring board is inserted/extracted, and a spiral rotating body of the ejector is formed on the axis. A bearing is provided so that the ejector is rotatable around the shaft portion and non-removably supported with respect to the storage box so that a portion of the ejector engages with the recess of the printed wiring board and the rotation lever is located in front of the storage box. It is said that

[Effect]

According to the above-mentioned means, after the printed wiring board is pushed into the storage box until its connecting part contacts the connector of the storage box, the ejector is rotated by turning the rotation lever of the ejector, thereby removing the recess of the printed wiring board. The helical rotating body engages with the printed wiring board and moves in the direction of inserting the printed wiring board into the storage box, so the printed wiring board can be further pushed into the storage box.
The pin arrangement of the plug on the printed wiring board can be inserted into the connector on the storage box.

〔Example〕

Fig. 1 shows an ejector before operation according to an embodiment of the present invention, is a side view thereof, and is a front view thereof, and Fig. 2 shows the ejector after operation, is a side view thereof, and is a front view thereof. .

In the figure, 1 is a guide plate, 2 is a guide rail, 6 is a storage box, and 7 is a printed wiring board, which are the same as those of the conventional device described above, and are therefore designated by the same reference numerals. 15 is an ejector according to the present invention; 1
6 is a shaft thereof, 17 is a spiral rotating body protruding from the outer periphery of the shaft 16, and 18 is a spiral rotating body 17.
A notch 19 provided at one location is a rotating lever provided at one end of the shaft portion 16. The material of the ejector 15 constructed in this manner is, for example, a rigid material such as hard plastic or metal.

Reference numeral 20 denotes a bearing portion formed by bending the open end of the guide plate 1; 21 is a recess provided above one end of the printed wiring board 7; has been done. At this time, the shaft portion 16 is supported by the bearing portion 20 in the same direction as the insertion direction of the printed wiring board 7, and the spiral rotating body 17 engages with the recess 21 of the printed wiring board 7.
Further, the rotary lever 19 is configured to be located in front of the storage box 6. Reference numeral 22 denotes a retaining portion of the ejector 15 attached to the shaft portion 16 of the ejector 15 protruding from the bearing portion 20, so that the ejector 15 cannot move in the axial direction.
0 and cannot be attached to or detached from the storage box 6.

The present embodiment has the above-mentioned configuration, and although not shown in the figure, the guide plate located below is also provided with an ejector 15 in the same manner as described above. Although this is also not shown, the printed wiring board 7 has a plug part, and the pin arrangement of this plug part is inserted into the connector of the storage box 6, and the printed wiring board 7 is electrically connected to the outside. This is the same as before.

In the above configuration, in order to mount the printed wiring board 7 in the storage box 6, the printed wiring board 7 is inserted into the guide rail 2 of the storage box 6 through the notch 18 of the ejector 15 before operation as shown in FIG. Insert the printed wiring board 7 into the connector (not shown) of the storage box 6 and push it in until it makes contact with the connector, until the recess 21 of the printed wiring board 7 is aligned as shown in FIG. The position corresponds to the spiral rotating body 17.

In this state, when the ejector 15 is rotated clockwise using the rotary lever 19, the spiral rotating body 17 of the ejector 15 engages with the recess 21 of the printed wiring board 7, and when the ejector 15 is further rotated, the spiral rotating body 17 Since the position of the printed wiring board 7 is moved in the insertion direction within the recess 21, the printed wiring board 7 is pushed into the storage box 6 by contacting one side of the recess 21 as shown in FIG. The pin arrangement and the like of the connectors (not shown) of the board 7 can be inserted into the connectors (not shown) of the storage box 6, and the mounting of the printed wiring board 7 into the storage box 6 is completed.

The clockwise rotation of the ejector 15 described above is as follows:
The printed wiring board 7 is mounted on the storage box 6 as described above by performing the mounting at an angle of about 270 degrees.

Printed wiring board 7 mounted in storage box 6 as described above
To remove the ejector 15 from the storage box 6, the ejector 15 is rotated counterclockwise using the rotary lever 19 in the state shown in FIG. Then, Ijiekta 15
The spiral rotating body 17 moves in the recess 21 in a direction opposite to the direction in which the printed wiring board 7 is inserted, so it comes into contact with one side of the recess 21 opposite to the above and accommodates the printed wiring board 7. When the printed wiring board 7 is moved in the pulling direction from the box 6, the unillustrated connectors of the printed wiring board 7 are pulled out from the unillustrated connectors of the housing box 6, resulting in the state shown in FIG. Thereafter, the printed wiring board 7 can be pulled out from the storage box 6 without any resistance.

Next, the load F when the printed wiring board 7 is inserted by the ejector 15 described above and the insertion force P of the printed wiring board 7
The relationship between the two will be explained based on FIG. FIG. 3 shows the ejector 15, and is a side view and a front view.

The relationship between load F and insertion force P is P={I ₂ /I ₁・
It is expressed as tan(α+λ)}・F. Note that α represents the contact angle between the helical rotating body 17 and the recess 21, and λ represents the friction angle.

Here, if we consider (α+λ) to be about 10° to 20°, then
Compared to the insertion force of the conventional ejector based on the lever principle, the insertion force of the ejector 15 of this embodiment can generate about 2 to 6 times as much force.

Next, the relationship between the rotation angle of the ejector 15 and the load will be explained based on FIG. 4 showing the relationship between the rotation angle of the ejector 15 and the load. In the figure, A indicates the insertion start position of the printed wiring board 7, B indicates the insertion end position, the vertical direction indicates the change in load, the horizontal direction indicates the change in the rotation angle of the ejector 15, and A indicates the conventional example. The curve showing the conventional load described above is a curve showing the load in this embodiment.

In the structure of the ejector 15 shown in this embodiment, the spiral rotating body 17 and the recess 2 of the printed wiring board 7
By changing the contact angle α with 1 for each rotation angle, the ratio of the insertion force P to the load F, I ₂ /I ₁ ·tan (α + λ), at each rotation angle can be changed. By optimizing the shape of the rotating body 17, as clearly shown in curve B shown in FIG. The required load on the ejector 15 can be kept almost constant.

Note that in the above embodiment, the printed wiring board 7 has a recess 21.
The helical rotating body 17 of the ejector 15 is
The structure is such that the printed wiring board 7 is moved by engaging with the recess 21, but this is done by attaching a small piece with a cam groove to the printed wiring board 7, and then engaging the helical rotating body 17 in the cam groove. The present invention is not limited to the structure of the embodiment described above, and any structure may be used as long as the action of the spiral rotating body 17 due to the rotation of the ejector 15 is transmitted to the printed wiring board 7.

[Effect of idea]

As explained above, in the present invention, a recess is formed in the edge of the printed wiring board near the end opposite to the plug, and the ejector is formed into a spiral rotating body having a spiral protrusion on the outer periphery of the shaft. , formed of a notch provided in a part of the helical rotating body in the axial direction so as not to interfere with insertion and removal of the printed wiring board, and a rotation lever provided at one end of the shaft portion for rotating the helical rotating body. The storage box has an axis parallel to the insertion/extraction direction of the printed wiring board near the opening side where the printed wiring board is inserted/extracted, and a part of the spiral rotating body of the ejector is printed on the axis. A bearing is provided that engages with the concavity of the wiring board and supports the ejector in a manner that allows the ejector to rotate around the shaft portion and not be detachable from the storage box so that the rotation lever is located in front of the storage box. .

In this way, the structure converts the rotational motion of the spiral rotating body into linear motion in the insertion/extraction direction of the printed wiring board by engaging a part of the spiral rotating body with the recess of the printed wiring board. Compared to an ejector with a lever part, it has the effect of greatly reducing the space occupied during installation and operation. This solves the problem of hindrances to connector placement and cable access, and has the effect of significantly reducing such wasted space.

Furthermore, since conventional ejectors are composed of a lever part and a protrusion, the lever part must be made longer in order to increase the force for inserting and removing printed wiring boards, which increases the space occupied. In the ejector of the present invention, the insertion/extraction force can be increased by changing the angle of the spiral rotating body, so the occupied area is not increased, and moreover, it is possible to obtain a much larger insertion/extraction force than the conventional insertion/extraction force. There are some effects that can be achieved.

Furthermore, conventional ejectors have the problem of being easily damaged due to stress concentration during operation, but the ejector of the present invention uses a spiral rotating body, so there is no extreme stress concentration and it has excellent strength. In addition, the structure is simple.

The ejector of the present invention changes the angle of the spiral rotating body for each rotation angle of the ejector,
Since the required load for the ejector to insert and remove the printed wiring board can be kept almost constant, operability and safety are greatly improved compared to conventional ejectors that cause sudden changes in load when operating the ejector. There is also. In addition, since it is easy to apply force by pinching and twisting the rotary lever, operability can be further improved.

In mounting, the guide plate of the printed wiring board storage box is used as a bearing, so the number of parts is kept to a minimum, and the structure is simple and has excellent strength.

[Brief explanation of the drawing]

Fig. 1 is a side view and front view showing an ejector before operation, showing an embodiment of the present invention, Fig. 2 is a side view and front view showing the ejector after its operation, and Fig. 3 is an ejector illustrating the principle of the ejector. Fig. 4 is a graph showing the relationship between the rotation angle of the ejector and the load, Fig. 5 is a side sectional view showing the conventional printed wiring board attachment/detachment structure, and Fig. 6 is a side view of the conventional ejector. . 4...Connector, 6...Accommodation box, 7...Printed wiring board, 15...Ejector, 16...Shaft portion, 17
... Spiral rotating body, 19 ... Rotating lever, 21
...Concavity.

Claims (1)

[Scope of Claim for Utility Model Registration] Having an ejector that presses and moves the printed wiring board in order to insert the connector of the printed wiring board into the connector installed in the storage box when mounting the printed wiring board in the storage box. In the printed wiring board attachment/detachment structure, a recess is formed in the edge of the printed wiring board near the end opposite to the plug, and the ejector is a spiral rotating body having a spiral protrusion on the outer periphery of the shaft. , formed of a notch provided in a part of the helical rotating body in the axial direction so as not to interfere with insertion and removal of the printed wiring board, and a rotation lever provided at one end of the shaft portion for rotating the helical rotating body. The storage box has an axis parallel to the insertion/extraction direction of the printed wiring board near the opening side where the printed wiring board is inserted/extracted, and a part of the spiral rotating body of the ejector is printed on the axis. The ejector is provided with a bearing that engages with the concave portion of the wiring board and supports the ejector in a manner that allows the ejector to rotate freely around the shaft and not be detachable from the storage box so that the rotation lever is positioned in front of the storage box. Printed wiring board removable structure.