JPS6017755Y2 - LCD display mobile watch - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a substrate for holding and mounting an electronic circuit of a liquid crystal display type portable watch.

The purpose of the present invention is to reduce manufacturing costs of electronic circuits including ICs.

Another purpose is to make it possible to clearly identify defective parts of electronic circuits and to facilitate the replacement of defective products.

The electronic circuit of a portable watch with a liquid crystal display can be broadly classified into the following elements.

That is, they include a crystal oscillator that is a time standard source, a slowing and slowing capacitor and a variable capacitor that adjust this vibration, and an IC that converts the clock standard source signal into a display signal.

Conventionally, this electronic circuit has been constructed as a single block, with all elements being soldered onto a one-layer or two-layer substrate.

This can be said to be good in terms of reducing the number of blocks that make up the watch body, but it has the following drawbacks.

(1) By configuring all the elements in the same block, the manufacturing process becomes longer and the product yield rate decreases, resulting in higher manufacturing costs.

(2) When a defect occurs during transportation or assembly, it is difficult to find the defective part, and when replacing the defective product, even if one of the elements is defective, the block must be replaced, resulting in wasted expensive elements. Become.

The present invention aims to provide an electronic circuit that is improved in these respects.

That is, the IC, which is an expensive component with relatively high defects, and other elements are completely separated into two parts.

ICs are sensitive to relatively high voltages such as static electricity, and may become defective in subsequent processes such as soldering.

Furthermore, there is an advantage in separating the IC and other elements because the causes of failure are different, such as crystal resonators being easily destroyed by excessive impact such as being dropped.

Embodiments of the present invention will be described below with reference to FIGS. 1, 2, and 3.

1 is an IC, 2 is a crystal resonator, 3 is a variable capacitor, 4 is a slowing capacitor, 5 is an IC lead plate that is a substrate that holds the IC (only a portion of the pattern is shown), and 6 is a circuit lead that holds other elements. A plate (pattern not shown).

7 is a liquid crystal display panel, and 8 is a connector that electrically connects the electronic circuit section and the liquid crystal display panel.

A panel frame 11 supports the connector and the liquid crystal display panel.

Since the IC lead plate 5 and the circuit lead plate 6 are connected by a spring 12 provided on the circuit lead plate, both can be freely removed.

Further, the positions of both are determined by pins 14 at the four corners.

In this way, the IC1 and other elements can be manufactured and inspected in independent processes, thereby shortening the manufacturing process and improving the yield rate.

Furthermore, it has the advantage of being easy to find and replace defective parts after being assembled as a watch body.

By the way, in addition to these elements, there are the following elements that have an organic relationship with the above-mentioned IC.

One is a power protection capacitor that allows the IC to continue operating accurately even if the power goes out for a short period of time due to shock while carrying the device.

The other is resistance reduction, which corrects to a constant value variations in threshold values that occur during IC processing.

Maintaining the threshold value of an IC at a constant value is necessary for an IC having a battery life display circuit or the like that detects a drop in power supply voltage and warns of battery life.

It is advantageous in terms of manufacturing for these elements that are particularly related to the IC to be placed on the same substrate as the IC.

Therefore, in this embodiment as well, these power protection capacitors 9,
The resistor 10 is fixed on the IC lead plate by soldering or the like.

According to the present invention, the panel frame supporting the display panel has a stepped portion on which the first circuit board is mounted, and a step portion on which the second circuit board is mounted.
The IC and the power supply compensation capacitor are connected and fixed to the first circuit board, and the ice crystal oscillator and the speed control capacitor are connected and fixed to the first circuit board. the first circuit board and the second circuit board are connected by a spring provided on one of the circuit boards, and the first circuit board and the liquid crystal display panel are connected by conductive rubber; Since the power supply battery is configured to pass through the notch of the second circuit board and be placed on the first circuit board, the following effects can be obtained.

a. Of the electronic elements necessary to form an electronic watch, an IC and a power supply compensation capacitor are connected and fixed to the first circuit board, and a crystal oscillator and adjustment capacitor are connected and fixed to the second circuit board. Since the connection between the first and second circuit boards is made by pressing a spring fixed to one circuit board and the other circuit board, one circuit board can be replaced even if some electronic components are damaged. It is possible to keep manufacturing costs and repair costs low.

b In addition, by fixing the IC and power supply compensation capacitor to the first circuit board, and providing the crystal resonator and adjustment capacitor to the second circuit board, the characteristics of the IC and crystal resonator can be easily adjusted to each circuit. This can be done on a single board, making it easier to inspect electronic components and significantly improving the yield of products.

C By arranging the first circuit board and the second circuit board in a stacked manner with a space between them, it is possible to make the watch floating, but in this application, the power supply battery penetrates the notch of the second circuit board. Since the second circuit board is placed on the first circuit board, the second circuit board falls within the thickness of the power supply battery, which has the effect of not substantially increasing the thickness.

Furthermore, since both the first and second circuit boards are positioned by the panel frame, special parts for positioning are not required, and an overall compact and low-cost movement can be provided.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing an embodiment of the present invention. FIG. 2 is a sectional view taken along line AA' in FIG. FIG. 3 is a sectional view taken along line BB' in FIG. 1...IC, 2...Crystal resonator, 5.
...ICI) - lead board, 6... circuit lead board, 7... liquid crystal display panel, 9...
Power protection capacitor, 10... Resistor, 13...
····battery.

Claims (1)

[Scope of utility model registration request] A stepped portion on which a first circuit board is placed is formed on the inner periphery of a panel frame that supports a liquid crystal display panel, so that the first circuit board and the second circuit board are stacked with a space between them. A supporting portion for the second circuit board is formed in the panel frame, an IC and a power supply compensation capacitor are connected and fixed to the first circuit board, and a crystal resonator and a speed control are connected to the second circuit board. the first and second circuit boards are connected and fixed, and the connection between the first and second circuit boards is achieved by pressing a spring fixed to at least one circuit board against the other circuit board; and the liquid crystal display panel, a conductive rubber is disposed between the liquid crystal display panel and the liquid crystal display panel to establish a connection, and the power supply battery is placed on the first circuit board by penetrating the notch of the second circuit board. LCD display type mobile clock.