JPH0545039Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Field of the Invention> This invention relates to a front structure of a control device having a liquid crystal display and applied to a counter device or the like.

<Prior art and its problems> Some control devices such as counter devices have a control device case divided into a rear case and a front case. As an example, as shown in FIG. 3, the front opening end 102a of a rear case 102 made of colored synthetic resin with terminal fittings 101 etc. disposed at the rear end is connected to a colored synthetic resin that forms a device case 103 together with the rear case 102. A front case 104 made of synthetic resin is fitted, and the front case 10
A backlight module 1 is mounted on a liquid crystal display 106 and a printed wiring board 107 in the case 103, facing the display window 105 formed in the display window 105.
08 are sequentially arranged, a transparent window plate 109 is fitted to the display window 105, and a display front sheet 110 is attached to the front surface of the front case 104.

The reason why the front case 104 is molded from a colored synthetic resin is to prevent the liquid crystal display 106 and the like from being seen through from around the vertical and horizontal side surfaces 104a of the front case 104.

However, with the above configuration, the display window 105 must be covered with the window plate 109, which increases the number of parts. 106
Since the electrodes etc. are arranged, the display window 105
There was a risk that static electricity would enter through the gap between the window plate 109 and the window plate 109, causing the display drive circuit (not shown) to malfunction.

<Purpose of the invention> This invention was made in order to solve the problems of the conventional ones mentioned above.It is a control equipment that can maintain an excellent appearance, reduce the number of parts, and especially prevent malfunctions caused by static electricity. It is intended to provide a front structure.

<Structure and effects of the invention> The front structure of a control device according to this invention is such that a front case, which together with the rear case constitutes an equipment case, is fitted into the front opening end of a rear case made of a non-transparent material. A backlight module is disposed on the rear side of a liquid crystal display disposed in the front case corresponding to the display surface portion on the front surface of the front case, and the backlight module is attached and the liquid crystal display is connected to the backlight module. A front structure of a control device in which a wiring board to be held in a front case is locked to a hook piece formed on the front case, wherein the front case is made of a translucent material, and the front case is made of a translucent material, and A non-light-transmitting sheet is attached to the front surface of the front case except for the display surface portion, with collar portions covering the upper and lower and left and right side peripheries of the front case connected.

According to this invention, since the front case is made of a translucent material, the number of parts is reduced compared to a case where the display window is covered with a window plate, and there is no risk of static electricity or dust entering, making it suitable for use. Operation can be ensured, and since the front surface of the front case except for the display surface is covered with a non-light-transmitting sheet, and the periphery of the side surfaces are covered with the collar of the rear case, the appearance is also good.

<Description of Embodiment> An embodiment of this invention will be described below with reference to the drawings.

FIGS. 1 and 2 are an exploded perspective view and a side sectional view, respectively, showing an example in which the front structure of a control device according to the invention is applied to a counter device.

In the figure, 1 is an electrically insulating non-transparent material;
For example, it is a rectangular cylindrical rear case made of colored synthetic resin or the like, and constitutes a mounting case 3 together with a front case 2 that is fitted into the front opening end 1a. A plurality of terminal window portions 6 are formed at the rear end of the rear case 1, which are partitioned by a plurality of partition wall portions 4 and upper and lower vertical wall portions 5 (5 ₁ , 5 ₂ ).

7 (7 ₁ , 7 ₂ ) are the first circuit parts mounted with counter circuit parts (not shown) and arranged facing each other in the vertical direction.
The set of printed wiring boards 8 (8 ₁ , 8 ₂ ) is a second set of printed wiring boards disposed between the two wiring boards 7 ₁ and 7 ₂ , and these printed wiring boards 7 and 8 are It is stored in the rear case 1 above,
The printed wiring board 7 is connected to first guide rails 9a, 9 formed on the upper and lower inner walls of the rear case 1.
b, and the printed wiring board 8 is supported by second guide rails (not shown) formed on the left and right inner walls of the rear case 1.

10 (10 ₁ to 10 ₄ ) are the terminal window portions 6 ₁ to 6 ₄
These terminal fittings are set opposite to each other, and terminal screws 11 (not shown in FIG. 1) are attached to each terminal fitting. 12 (12 ₁ to 12 ₄ ) are terminal blocks, and terminal blocks 12 ₁ and 12 ₂ respectively correspond to terminal fittings 10 ₁ and 10 ₂ in which a plurality of terminal fittings are made into one set.
2 ₃ and 12 ₄ correspond to terminal fittings 10 ₃ and 10 ₄ , respectively.

The terminal fitting 10 is formed by bending a metal plate into a substantially L-shape, and a screw hole 13 into which the terminal screw 11 is screwed is formed in one piece 10a, and a screw hole 13 into which the terminal screw 11 is screwed is formed at the tip of the one piece 10a. , a protrusion 14 is formed, and a connecting fixing piece 16 is bent and inserted into a through hole 15 formed in the corresponding printed wiring board 7, 8 and soldered to the other piece 10b.

The terminal blocks 12 are made of electrically insulating synthetic resin, and each has a cavity 17 that does not prevent the terminal screw 11 from entering. A fitting hole 18 into which the protrusion 14 of the terminal fitting 10 is fitted is formed at the rear edge of the upper surface of the terminal block 12, and a notch formed in the other piece 10b of the terminal fitting 10 is formed on the lower surface. A protrusion 20 that fits into the terminal fitting 1 is integrally formed with the protrusion 14 and the fitting hole 18, as well as the notch 19 and the protrusion 20, respectively.
0 to the terminal block 12 and constitute first and second fitting portions of both 10 and 12.

Reference numerals 21 and 21 designate engagement protrusions protruding from the lower surface of each of the terminal blocks 12, and are engaged with notch-shaped holes 22 and 22 formed at one end of the corresponding printed wiring boards 7 and 8, respectively. The terminal block 12 is positioned using the terminal block 12. 23 is the above terminal block 1
This is a groove formed between the respective terminal metal fitting settings in 2 ₁ and 12 ₂ , and is fitted into the root of the partition wall 4. Reference numerals 24 and 24 denote elastic engagement pieces formed on both end faces of the terminal blocks 12 ₁ and 12 ₂ , which can be engaged and detached from engagement holes 25 and 25 formed on the left and right sides of the rear side of the rear case 1. It is becoming more and more engaged. The above terminal block 12 ₁ ,
Connecting holes 26, 26 are formed in each upper surface of terminal blocks 12 ₂ , into which connecting pins 27, 27 formed on each side of terminal blocks 12 ₃ , 12 ₄ are inserted.

Reference numerals 28 and 28 are engagement convex portions formed on both sides of the front end sides of the printed wiring boards 7 ₁ and 7 ₂ , which engage locking slits 29 a and 29 a formed on the engagement arm pieces 29 of the front case 2 . This is to engage the object.

The front opening end 1a of the rear case 1 has upper and lower and left and right side surfaces 2b of the front case 2.
A collar portion 30 that covers the periphery of is integrally formed.

The front case 2 is made of a light-transmitting material, for example, a transparent synthetic resin, and has a well-known liquid crystal display 31 and a rear panel of the liquid crystal display 31 inside corresponding to the display surface part 2a on the front side. A backlight module 32 for a liquid crystal display located on the side is provided. Reference numeral 33 denotes a printed wiring board on which the backlight module 32 is mounted and placed in a vertical position, and a display drive circuit (not shown) and the like are set. A pair of rubber connectors 34, 34 are inserted. Engagement protrusions 33a are formed on the upper end surface and the left and right end surfaces of the wiring board 33, respectively. The wiring board 33 is attached to the front case 2 by being engaged with the hook pieces 35, and thereby the liquid crystal display 31 and the like are also held on the front case 2 side. 36 is a groove formed in the side surface 2b of the front case 2, and 37 is an O-ring fitted into the groove 36.

A shallow recess 38 is formed on the front surface of the front case 2, located below the display surface portion 2a, and a well-known seat switch 39 is fitted into this recess 38. 40 is formed in the recess 38 and connects to the lead portion 39a of the seat switch 39.
This is an insertion hole through which the Reference numeral 41 denotes a non-light-transmitting front sheet attached to the front surface of the front case 2, in which an exposure hole 42 of the display surface portion 2a is formed.

In the above configuration, each terminal fitting 10 is locked to the corresponding terminal block 12 and attached to the corresponding printed wiring board 7, 8, so that the terminal fitting 10
The connecting fixing piece 16 is fixed by soldering.

On the other hand, there is a liquid crystal display 3 on the back side of the front case 2.
1 and a printed wiring board 33 on which a backlight module 32 is mounted, and the liquid crystal display 3
1 is connected with the rubber connectors 34, 34, and the engaging protrusion 33a of the wiring board 33 is engaged with the hook piece 35 on the front case 2 side,
The liquid crystal display 31 and the like are held on the front case 2 side. Furthermore, after setting the seat switch 39 in the recess 38 on the front surface of the front case 2, a non-transparent front sheet 41 is attached to the front surface.

Then, the engagement protrusion 28 of the printed wiring board 7 is engaged with the engagement slit 29a of the engagement arm piece 29 in the front case 2. In this state, the printed wiring boards 7 and 8 are inserted into the rear case 1, and the elastic engagement pieces 24 of the terminal block 12 are inserted into the rear case 1.
When the printed wiring board 7 is engaged with the side engagement hole 25, the printed wiring board 7 is fixed to the rear case 1, and the front case 2 is attached to the rear case 1 with the terminal fitting 10 exposed to the terminal window 6. It is fitted.

The seat switch 39 inputs set values and the like to a control circuit built into the printed wiring board 7, and the set values and current values are displayed on the liquid crystal display 31.

The display contents of the liquid crystal display 31 can be visually recognized through the display surface portion 2a of the front case 2.

That is, since the front case 2 is made of transparent synthetic resin, the display contents of the liquid crystal display 31 can be seen through without providing a display window or a window plate covering it. In other words, the window plate can be omitted. It can contribute to reducing the number of parts. Furthermore, even if the front case 2 is transparent, the surroundings of the upper and lower and left and right side surfaces 2b are colored by the colored parts 3 of the rear case 1.
Moreover, since the non-transparent front sheet 41 covers the parts other than the front display surface part 2a, the appearance is maintained good, and during molding, only the transparency of the display surface part 2a is covered. can be managed, and management costs are also reduced.

In particular, by molding the front case 2 from transparent synthetic resin, there is no longer any risk of static electricity entering through the gap between the window plate and the display window, which is the case in the past, and malfunctions and incorrect displays caused by this are prevented. Not only that, but it also has improved dustproof and waterproof properties.

In the above example, the front case 2 is made of transparent synthetic resin, but this material is not limited to being transparent, and may have a translucency to the extent that the displayed content can be seen through the display surface portion 2a. That's fine.

[Brief explanation of the drawing]

1 and 2 are an exploded perspective view and a side sectional view showing an example of a counter device to which the front structure of a control device according to the invention is applied, respectively, and FIG.
The figure is a side sectional view of a counter device to which the front structure of a conventional control device is applied. 1... Rear case, 1a... Front opening end, 2
...Front case, 2a...Display surface section, 2b...
... Side surface, 7 ... Printed wiring board, 10 ... Terminal fitting, 39 ... Switch, 30 ... Collar part, 3
1... Liquid crystal display, 32... Back light module, 33... Wiring board, 33a... Engaging protrusion,
35...Hook piece, 41...Non-transparent sheet.

Claims (1)

[Scope of utility model registration request] A front case that is fitted into the front opening end of a rear case made of a non-transparent material, which has terminal fittings at the rear end and houses a printed wiring board that constitutes a control circuit inside; A liquid crystal display disposed in the front case corresponding to the display surface on the front, a back light module disposed on the rear side of the liquid crystal display, and a back light module installed in the front case. A wiring board that is engaged with a hook piece formed on the case to hold the liquid crystal display on the front case, and a switch that is arranged on the front surface of the front case excluding the display surface, and the front case is transparent. The front opening of the rear case is connected to a collar part that covers the top, bottom, left and right sides of the front case, and the front surface of the front case is non-transparent except for the display surface part. A flexible material sheet is pasted, and set values are input into the control circuit using the switch, and the set values are displayed on the liquid crystal display so that they can be viewed from the display surface on the front of the front case. The front structure of the control equipment is characterized by: