JPH04133334U - Structure that prevents noise from coming into contact with plastic parts and circuit board - Google Patents

Abstract

(57) [Summary] [Purpose] In order to prevent the operation button made of a plastic member attached to the front panel from falling off from the front panel, a drop-prevention boss is provided that protrudes from the operation button and an electronic circuit made of a phenolic resin material is provided. Because the electronic circuit board is in direct contact with the operation button fall prevention boss that is pressed against the board and fixed between the front panel and the electronic circuit board, the temperature rise inside the casing will cause the operation button fall prevention boss to To prevent abnormal noise from being caused by rubbing against an electronic circuit board when thermally expanding and moving from an initial contact position. [Structure] Silk printing is applied to the electronic circuit board 5 that the drop-off prevention boss 4 of the operation button 3 comes into contact with, and the coating film 6 prevents the drop-off prevention boss 4 of the operation button 3 from coming into direct contact with the electronic circuit board 5. This makes it possible to reliably prevent abnormal noises from being generated even if the drop-off prevention boss of the operation button expands thermally due to a temperature rise from the electronic circuit or the like inside the housing and moves from its initial contact position.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

The present invention aims to prevent abnormal noise from coming into contact with plastic parts used in electronic equipment, etc. This relates to the stop structure.

0002

[Conventional technology]

Conventionally, the operation button protrudes from the front panel and presses against the electronic circuit board. It is common to have a structure with a fall prevention boss to prevent it from falling off. , boss made of plastic material to prevent the operation button from falling off, and phenolic resin material Since the electronic circuit board is in direct contact with the When the electronic circuit board expands due to the internal temperature rise and moves from the initial contact position, the electronic circuit board It rubs and makes an abnormal noise. At this time, remove the operation button drop-prevention boss and the electronic circuit board. An additional step was taken to apply grease to the contact point of the plate to prevent the occurrence of abnormal noise.

0003

[Problem that the idea aims to solve]

Remove the operation button to prevent it from falling off the front panel. The operation button is made of plastic and has a structure in which the fall prevention boss is pressed against the electronic circuit board. The falling-off prevention boss expands due to the rise in temperature inside the casing and moves from its initial contact position. Because it is not possible to prevent the operation button from falling off, It had the disadvantage of rubbing and making noise.

0004

[Means to solve the problem]

This invention consists of a front panel placed on the front of the housing and a front panel attached to the front panel. between the operation button made of attached plastic material and the housing and front panel. An electronic circuit board made of phenolic resin materials, etc., and a protrusion from the operation button. Press it against the electronic circuit board to prevent the operation button from falling off the front panel. It is equipped with a drop-prevention boss provided to prevent the operation button from falling off. By applying a coating film such as silk printing to the sub circuit board, the button can be prevented from falling off. The boss to prevent the operation button from falling off is installed in the housing so that the button does not come into direct contact with the electronic circuit board. The coating prevents resonance even if it expands due to internal temperature rise and moves from the initial contact position. The loss-adding structure prevents abnormal noise from occurring.

[0005]

【Example】

The present invention will be explained by way of an example. Figure 1 is a sectional view showing one embodiment of the present invention. Figure 2 shows that the boss to prevent the operation button from falling off expands due to the rise in temperature inside the casing. It is an explanatory view showing a state where it moves from a contact position. Freon placed on the front of housing 1 The operation button 3 made of a plastic member attached to the top panel 2 is operated by an external force A etc. The fall prevention boss 4 is made of phenolic resin to prevent it from falling off the front panel 2. The material is pressed onto the electronic circuit board 5 and mounted between the front panel 2 and the electronic circuit board 5. It has a structure in which a switch 7 provided on an electronic circuit board 5 is operated. operation The falling-off prevention boss 4 of the button 3 expands thermally in the direction of arrow B due to the rise in temperature inside the housing 1. Ru. The heat-expanded falling-off prevention boss 4 is always pressed against the electronic circuit board 5; It moves in the direction of arrow C and absorbs the thermally expanded length. At this time, the fall prevention boss If the electronic circuit board 5 and the electronic circuit board 4 are in direct contact with each other, abnormal noise will occur. Coating film 6 is applied by silk printing. Silk-printed coating 6 protects the boss 4 from falling off and the electric wire. Since the sub-circuit board 5 is no longer in direct contact, there is vibration loss between the operation button 3 and the electronic circuit board. The noise is added, and abnormal noise due to resonance is no longer generated. Also, instead of the coating film 6 shown in FIG. The uneven pattern surface increases frictional resistance and prevents movement due to thermal expansion. Ru.

[0006]

[Effect of the idea]

According to the present invention, a boss made of a plastic member to prevent the operation button from falling off and a phenol Since electronic circuit boards such as resin-based parts are not in direct contact with each other, the temperature inside the housing may rise. The boss to prevent the operation button from falling off expands thermally, causing an abnormal noise even if it moves from its initial contact position. It is possible to reliably prevent this from occurring.

[Brief explanation of drawings]

FIG. 1 is a sectional view of essential parts of an embodiment of the present invention.

FIG. 2 is a diagram showing a state in which the drop-off prevention boss of the operation button moves.

[Explanation of symbols]

1 Housing 2 Front panel 3 Operation buttons 4 Fall prevention boss 5 Electronic circuit board 6 Paint film 7 Switch

Claims (2)

[Scope of utility model registration request] Claim 1: A front panel disposed on the front surface of a housing, an operation button made of a plastic member attached to the front panel, an electronic circuit board disposed between the housing and the front panel, and an electronic circuit board protruding from the operation button. Equipped with a fall prevention boss that is provided to prevent the operation button from falling off the front panel by pressing against the circuit board.A coating film is applied to the electronic circuit board that the operation button fall prevention boss comes into contact with to prevent the operation button from falling off. A structure for preventing noise generation at a plastic component board abutting part, which is characterized by preventing direct contact between the boss and the electronic circuit board. 2. A structure for preventing noise generation between a plastic component and a substrate in contact with each other, characterized in that the coating film is formed into a circuit pattern to increase frictional resistance.