JPH0450635B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a memory card, and more particularly to a memory card as an external storage device for externally transmitting programs or data to and from an electronic device having a program function.

Prior Art Conventionally, in many electronic devices that have a program function, a memory card as an external storage device that stores a predetermined program or data in advance can be removably attached to the device body as needed. It is structured in such a way that it is possible to expand its functionality.

For this reason, instead of having to operate the keyboard provided on the device itself to program or enter data, which is a tedious operation, the operator inserts a memory card that stores the necessary programs or data. All you have to do is do it, and it has become extremely convenient.

The structure of a conventional memory card of this type and an electronic device to which it is installed are shown in FIGS. 1 to 3.

1 to 3, the reference numeral 1 is a calculator, and this calculator 1 has an upper case 1a and a lower case 1b.
It has a necessary arithmetic circuit, power supply, etc. inside.

A keyboard 2 consisting of a large group of input keys is provided on a part of the front side of the calculator 1, and a display 3 is provided near the keyboard 2.

On the other hand, the one indicated by code 4 is a memory card.
It is formed in the shape of a flat casing, and a long and narrow opening 6 is formed in a part thereof in a state that extends across the width direction, and the contact pattern 5 is exposed facing this opening 6.

On the other hand, on the back side of the lower case 1b of the calculator 1, a flat space 7 is formed in which the memory card 4 is accommodated, as shown in FIG. A pressure contact 8 is provided at a position corresponding to 5 in a slightly protruding state. This space 8 has a lid 9 that can be opened and closed.
is occluded by There is a hook 9 on the free end side of the lid 9.
a is provided, and this hook 9a is removably locked to a locking piece 10 provided on the lower case 1b side.

As shown in FIG. 3, a printed circuit board 11 is provided inside the memory card 4, and the contact pattern 5 is formed on this circuit board and faces the opening 6.

In addition, various memory elements 1 are mounted on the printed circuit board 11.
2 is installed.

An opening 13 is formed in the lower case 1b at a position corresponding to the contact pattern 5 of the memory card, and a press-contact type connector 14 is provided facing the opening 13, with the press-contact contact 8 at its tip. It is provided.

In FIG. 3, the reference numeral 15 indicates a printed circuit board on the main body side, and the reference 9b indicates a rotation axis of the lid 9.

With this structure, when the memory card 4 is housed in the flat space 7, the contact pattern 5 and the pressure contact 8 are brought into contact, and the lid 9 is closed, the pressure contact 8 is elastically deformed to ensure electrical connection. Continuity can be measured.

However, when the above structure is adopted, since the contact pattern 5 is exposed through the opening 6 of the memory card 4, it corrodes due to contact with the outside air.
There is a drawback that if a contact failure occurs or if an operator touches the contact pattern 5 under direct guidance, static electricity is directly applied and the memory element 12 is destroyed.

In order to overcome these drawbacks, a structure was adopted in which a shutter plate that could be opened and closed was provided inside the memory card.

Figures 4 to 8 show the conventional structure with a shutter plate.
As shown in the figure.

In FIGS. 4 to 8, the same parts as in FIGS. 1 to 3 are given the same reference numerals, and their explanations will be omitted.

In FIGS. 4 to 8, the reference numeral 16 is a shutter plate that is generally T-shaped as a whole, and a part of the shutter plate has a shape that is almost the same as the opening 6 formed in the upper plate 17. rectangular opening 1 with
6a, a protrusion 16b is protruded from the center of the side edge opposite to the opening 16a, and a protrusion 18 is protruded from the upper surface of the protrusion 16b. This protrusion 18
is a long hole 19 formed in the vicinity of the opening 6 of the upper plate 17 of the memory card and perpendicular thereto.
is projected outward through the

Further, a guide plate 20 is arranged in the same plane as the shutter plate 16. A notch 20b into which the projecting piece 16b is slidably fitted is formed on the side edge of the guide plate 20, and guides the shutter plate 16 linearly.

On the other hand, a spacer 21 made of an insulating material is arranged between the printed circuit board 11 and the shutter board 16 to insulate the space between them, and an opening 21a is formed at a position corresponding to the contact pattern 5.

On the other hand, through holes 20b and 21b are formed in the guide plate 20 and the spacer 21 at positions corresponding to the earth pattern 11a formed on the printed circuit board 11, and an earth spring 22 is fitted into these through holes 20b and 21b. The upper and lower ends of the earth spring 22 are in contact with the upper plate 17 and the earth pattern 11a. As a result, since the shutter plate 16 is always grounded via the earth spring 22, even if static electricity is directly applied when the shutter plate 16 is closed, the static electricity can be spread and damage caused by static electricity can be prevented.

In FIG. 8, the reference numeral 23 indicates the lower case of the memory card.

If such a structure is adopted, the contact pattern can be covered by closing the shutter plate.
The contact pattern is not exposed directly to the outside, which prevents corrosion of the contact pattern. The shutter plate is made of a material with good conductivity, such as metal, and the shutter plate and the electronic circuit of the memory card are grounded to prevent static electricity. This eliminates problems such as destruction of the memory element by the shutter plate.

However, if the shutter plate is made of a metal material to prevent electrostatic damage, if the shutter plate is pressed and there is little space between the shutter plate and the contact pattern when the shutter plate is closed, multiple contact patterns and the shutter plate will be damaged. There is a disadvantage that the contact patterns may come into contact with each other, causing a short circuit between the contact patterns and, as a result, destruction of the memory element.

Furthermore, if a memory card having such a structure is inserted into the main body of the device with the shutter plate closed, this will also cause a short circuit between the pressure contacts, which may lead to the destruction of the electronic circuit.

Furthermore, if the shutter plate is made of a metal material, there is a drawback that the shutter plate may be deformed and cannot be opened and closed smoothly.

Purpose The present invention has been made in order to eliminate the drawbacks of the conventional art as described above, and an object of the present invention is to provide a memory card that is easy to operate and configured so as to prevent destruction of electronic circuits, etc. .

Embodiments Hereinafter, details of the present invention will be explained based on embodiments shown in the drawings.

FIG. 9 explains one embodiment of the present invention, and the same parts in the figure as in FIGS. 4 to 8 are given the same reference numerals, and the explanation thereof will be omitted.

In this embodiment, the shutter plate 16 is formed by punching out a metal plate in the same shape as the conventional one, but except for the protrusion 16b, the shutter plate 16 is made of a material with excellent insulation and lubricity, such as fluorine resin. A solid lubricant coating 24 is formed. This solid lubricating oil film 24 is formed on both the front and back surfaces except for the protruding piece 16b.

If a shutter plate with such a structure is used, the solid lubricant coating with excellent insulating properties will prevent short-circuit accidents when the shutter plate 16 comes into direct contact with the pressure contact 8, etc., and will also prevent short circuits from occurring when static electricity is applied. If an earth spring is provided as in the conventional case, static electricity can be released from the protrusion 16d without a solid lubricant film through the earth spring, and electrostatic damage to the memory element will not occur.

As is clear from the above description, the present invention employs a structure in which the shutter plate, which freely opens and closes the opening where the contact pattern of the memory card is exposed, is covered with a solid lubricant film with excellent insulation properties. Therefore, even if the shutter plate and the pressure contact on the electronic equipment side are connected, a short circuit will not occur, and even if static electricity is applied, the static electricity will be dissipated through the part of the shutter plate that does not have a solid lubricant film. Therefore, electrostatic discharge damage to the memory element does not occur.

[Brief explanation of the drawing]

Figures 1 to 3 explain the conventional structure.
Fig. 1 is an overall perspective view of an electronic device equipped with a memory card, Fig. 2 is a perspective view of the electronic device seen from the back side, Fig. 3 is a sectional view taken along line A-A in Fig. 2, and Fig. 4-4 Figure 8 explains another conventional structural example.
The figure is a perspective view of the memory card with the shutter closed, Figure 5 is a perspective view of the memory card with the shutter open, Figure 6 is a partially enlarged longitudinal side view, and Figure 7 is a plan view of the main parts. , FIG. 8 is an exploded perspective view, and FIG. 9 is a perspective view of a shutter plate illustrating an embodiment of the present invention. 1...Electronic equipment, 4...Memory card, 5...
... Contact pattern, 6 ... Opening, 8 ... Pressure contact, 9 ... Lid, 11 ... Printed circuit board, 14 ...
Pressure type connector, 16... Shutter plate, 16b
...Protrusion piece, 17...Top plate, 18...Protrusion, 19...
...Long hole, 24...Solid lubricant coating.

Claims (1)

[Claims] 1. In a memory card that is removably attached to an electronic device with a programming function and is used to send and receive data, an opening formed in a part of the memory card is exposed and electrically connected to the main body of the electronic device. A memory card characterized in that the shutter plate, which is provided above the contact pattern and can be opened and closed, except for a part thereof, is covered with a solid lubricant film with excellent insulation properties.