GB1566489A - Electronic timpepiece - Google Patents

Description

(54) ELECTRONIC TIMEPIECE (71) We, CITIZEN WATCH CO., LTD., a Japanese corporate body of 1--99-18, Nishishinjuku, Shinjuku-ku, Tokyo, Japan, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed to be particularly described in and by the following statement:- This invention relates to an electronic timepiece comprising a module composed of four constitutional elements, i.e. a liquid crystal cell, a liquid crystal cell position determining member for receiving the liquid crystal cell therein, a circuit substrate arranged beneath the member and a protective cover arranged beneath the circuit substrate.

In an electronic timpiece for displaying time, etc. by means of a display using a liquid crystal, photodiodes, etc., that is, in a so-called digital type electronic timepiece, switching operations for correcting and changing over displays, etc. are complex and troublesome so that in practice it is difficult to effect such switching operations by means of only one switch part such as a winding stem, etc. However, provision of a number of switch parts not only makes the timepiece complex in construction and arrangement but also makes the switch parts troublesome in assembling. In addition, most such switch parts are operable by push buttons, so that the push buttons must be constructed such that they are stopped at a given position when they are pushed for the purpose of ascertaining whether or not the switch part has been operated in the desired manner.In addition, when a circuit substrate is formed of ceramics, etc. which are brittle particularly due to unfirm bonding structure. between metal forming the wiring pattern and contacts and ceramics, a force must not be applied thereto when the movable switch part is operated.

An object of the invention therefore, is to provide an electronic time piece comprising a module constructed and arranged such that the above mentioned drawbacks are eliminated, that switch parts easy to assemble and reliable in operation, and that a circuit substrate formed, for example, of ceramics is prevented from being broken by operating the switch parts.

In accordance with the invention there is provided an electronic timpiece comprising a module composed essentially of a liquid crystal cell, a liquid crystal cell position determining member receiving said liquid crystal cell, a circuit substrate having a first face arranged adjacent said member and a protective cover arranged adjacent a second face of said circuit substrate, said second face being opposite said first face, and said protective cover having switch parts secured thereto for controlling the timepiece.

An embodiment of the invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a plan view of a circuit substrate of an electronic timepiece according to the invention; Figure 2A is a plan view of a protective cover of an electronic timepiece according to the invention Figure 2B is a plan view of the opposite side of the protective cover shown in Figure 2A; Figure 2C is a section on line I-I of Figure 2B to an enlarged scale: Figure 2D is a section on line Il-Il of Figure 2A to an enlarged scale; Figure 2E is a section on line Ill-Ill of Figure 2A to an enlarged scale:: Figure 3 is a plan view of a liquid crystal cell position determining member of an electronic timepiece according to the invention Figure 4A is a plan view of a module of an electronic timepiece according to the invention; and Figure 4B is a section on line IV--IV of Figure 4A to an enlarged scale.

In Figure 1 is shown a circuit substrate 1 formed of ceramics. Reference numeral 2 designates a crystal oscillator; 3 a trimmer condenser; 4 a temperature compensation condenser; 5 two voltage step-up condensers: and 6 an illumination lamp.

These circuit elements 2 to 6 are secured by soldering to the circuit substrate 1 and are made electrically conductive to a wiring pattern (not shown) printed on the circuit substrate 1. It is to be understood that the face of the substrate 1 shown in Figure 1, on which the wiring pattern is printed, faces downwardly in the section of Figure 4B.

The circuit substrate I is provided at its opposite surface with circuit chips (not shown).

In Figure 2A is shown a protective cover 7 formed, for example, of an insulating plastics material. Reference numeral 8 designates a display change-over switch part; 9 a correction switch part; 10 a lamp switch part and 11 a return-to-zero switch part. These switch parts 8 to 11 are formed of resilient metal sheet and engage with dowels projecting upwardly from the protective cover 7 and are secured thereto by deforming the upper ends of these dowels by heating under pressure. Figure 2D shows the switch part 10 secured in this manner.

As shown in Figure 2D which is a section on line Il-Il of Figure 2A, the switch part 10 has an outer end 10a engaged by an electrically-conductive portion of a push button 18 provided at a side portion of a timepiece case (not shown), when the push button is pushed. Similarly, the outer ends 8a, 9a and 1 la of the switch parts 8, 9 and Il are each engageable by a respective push button (not shown) similar to push button 18. Other resilient ends 8b, 9b, 10b and 1 lib of the switch parts 8 to 11 are directly connected to contacts on the wiring pattern of the circuit substrate 1 when the circuit substrate 1 is assembled together with a liquid crystal cell position determining member 16 to be described later with reference to Figure 3.

Reference numeral 12 designates a connection part which functions to electrically connect the circuit substrate 1 to the push button 18. The connection part 12 is formed of resilient metal sheet and is provided at its outer end with bifurcated portions 12a, 12a adapted to be in contact with opposite side surfaces of an electrically conductive tube 19 as shown in Figure 2E which is a section on line Ill-Ill of Figure 2A, the tube 19 slidably receiving and being electrically connected to the push button 18. As a result, the connection part 12 functions to connect the wiring pattern on the circuit substrate 1 through the tube 19 to the push button 18 and thus to the switch part 10. The other end 12b of the connection part 12 is connected to a contact on the wiring pattern of the circuit substrate I in a similar manner to those of the other switch parts 8 to 11.It is to be understood that further connection parts 12 (not shown) are similarly provided for each of the switch parts 8, 9 and 11 and their respective push buttons, each connection part being in engagement with an electrically conductive tube 19.

The protective cover 7 for covering the circuit substrate 1 is provided at its center with an opening 7a for receiving an electric battery (not shown) therein and is provided at its periphery with an opening 7b for receiving the crystal oscillator 2 therein. In addition, the protective cover 7 functions to cover the other circuit elements, i.e., the trimmer condenser 3, temperature compensation condenser 4 and voltage stepup condensers 5.

As shown in Figure 2B and in Figure 2C which is section on line I-I of Figure 2B, the protective cover 7 is provided at its diametrically opposite portions with tubes 13, 13, each having an enlarged diameter portion 13a. Each tube 13 is secured to the protective cover 7 by means of the enlarged diameter portion 13a and a seat 14.

Reference numeral 15 designates a resilient holder composed of a generally annular-shaped spring split in its periphery to form ends 15a, 15a, the holder also having a projection 15b and two diametrically opposed projections 15c, 15c. The ends 15a, 15a serve to hold the electric battery therebetween and the projection 15b is urged against the crystal oscillator 2 so as to hold it. The projections 15c, 1 sic extend through openings 7c in the protective cover 7 and are connected to contacts on the wiring pattern of the circuit substrate 1.

In Figure 3 is shown a position determining member 16 for the liquid crystal cell 17, the member 16 being of insulating plastics material having a central opening and provided at its side portions with holes 16a, 16a. The tubes 13, 13 of the protective cover 7 are extended through these holes 16a, 16a and upper and lower ends of the tubes 13, 13 are threadedly engaged with screws so as to sandwich the circuit substrate 1 between the protective cover 7 and the liquid crystal cell position determining member 16 as shown in Figure 4B.

The liquid crystal cell position determining member 16 is provided at its end portions with opposed projections 16b, 16b; 16c, 16c for determining the positions of display component parts of the cell 17 such as a liquid crystal cell polarizing plate, reflecting plate, light guide plate, etc. (not shown); is provided at its side portions with two grooves 16d, 16d through which are inserted electrically conductive rubber connectors for connecting the wiring pattern from the circuit chips to external contacts of the liquid crystal cell 17; and is provided at its side portion with four dowels 16e, 16e, 16e, 16e for determining position of the liquid crystal cell 17. All of these portions of the liquid crystal cell position determining member 16 function to locate the liquid crystal cell 17 which is received in the central opening of the member.

In addition, the liquid crystal cell position determining member 16 is also provided at its end portions with four stop portions 16f, 16f, 16f, 16f each formed as a notch. Each of these four stop portions is located at that portion of the liquid crystal cell position determining member 16 which corresponds to a respective one of the switch parts 8 to 11.

In Figure 4A is shown a module comprising the liquid crystal cell 17 assembled together with the circuit substrate I sandwiched between the protective cover 7 and the liquid crystal cell position determining member 16. As shown in Figure 4A and in Figure 4B which is a section on line IV-IV of Figure 4A, each of the outer ends 8a to I la of the switch parts 8 to 11 is opposed to a respective one of the stop portions 16f of the liquid crystal cell position determining member 16. Thus, the outer end 9a of the switch part 9 is urged by its push button (similar to push button 18) against its stop portion 16f when the push button is pressed. In a similar manner, the push buttons associated with the switch parts 8, 10 and 11 are arrested by a corresponding one of the stop portions 16f.

As a result, a user can easily feel the mode of operation of the switch parts, whereby he is informed that the switch operation has been completed. In addition, the external force for operating the switch parts is arrested by the liquid crystal cell position determining member 16 which is mechanically stronger than the other timepiece parts, so that there is no risk of the other timepiece parts being broken.

The timepiece case is not shown but it is to be understood that it encloses the module and that all the push buttons, such as push button 18, for operating the switch parts 8 to 11 are mounted for movement in a side wall of the case.

As described hereinbefore, in the electronic timepiece all of the switch parts are secured to the protective cover, the switch parts are simple in construction, and they can easily be assembled together with any other timepiece parts. In addition, since the external force for operating the switch parts is limited in its effect by the mechanically strong timepiece part which forms the liquid crystal cell position determining member, there is no risk of the other timepiece parts being broken.

Moreover, the switch parts are stopped in their movement at a given position, so that the user can feel the mode of the switching operation whereby he can correctly operate the switch parts.

In addition, in accordance with an advantageous feature of the invention, provision may be made of bifurcated connection parts 12 each formed as a spring and each connected to an electrically conductive tube 19 receiving a push button such as push button 18. As a result, if the connection parts 12 are supplied with a voltage, it is possible to apply the voltage through the connection parts 12, tubes 19 and push buttons to the switch parts 8 to 11.

Such a construction and arrangement of the switch parts and connection parts are very useful in that they permit a rear cover to be formed of a non-electric-conductive material as compared with the prior art electronic timepieces in which the voltage is applied to the switches through the rear cover.

WHAT WE CLAIM IS: 1. An electronic timepiece comprising a module composed essentially of a liquid crystal cell, a liquid crystal cell position determining member receiving said liquid crystal cell, a circuit substrate having a first face arranged adjacent said member and a protective cover arranged adjacent a second face of said circuit substrate, said second face being opposite said first face, and said protective cover having switch parts secured thereto for controlling the timepiece.

2. An electronic timepiece according to Claim 1, wherein said circuit substrate is provided on said second face with a wiring pattern having contacts, and each of said switch parts is formed of metal sheet and is provided with a first resilient portion directly connected to a respective one of said contacts.

3. An electronic timepiece according to Claim 2, wherein both said liquid crystal cell position determining member and said protective cover are formed of an insulating plastics material, said circuit substrate is formed of ceramics, and each of said switch parts is provided with a second, resilient portion arranged at the periphery of said protective cover, and a push button is provided for each said switch part, each push button being mounted for movement in a side surface of a timepiece case enclosing said module and each push button having an electrically conductive portion, the arrangement being such that when a push button is pushed its electrically conductive portion engages a respective said second, resilient portion to complete a circuit.

4. An electronic timepiece according to

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (6)

1. **WARNING** start of CLMS field may overlap end of DESC **.

   contacts of the liquid crystal cell 17; and is provided at its side portion with four dowels 16e, 16e, 16e, 16e for determining position of the liquid crystal cell 17. All of these portions of the liquid crystal cell position determining member 16 function to locate the liquid crystal cell 17 which is received in the central opening of the member.

   In addition, the liquid crystal cell position determining member 16 is also provided at its end portions with four stop portions 16f, 16f, 16f, 16f each formed as a notch. Each of these four stop portions is located at that portion of the liquid crystal cell position determining member 16 which corresponds to a respective one of the switch parts 8 to 11.

   In Figure 4A is shown a module comprising the liquid crystal cell 17 assembled together with the circuit substrate I sandwiched between the protective cover 7 and the liquid crystal cell position determining member 16. As shown in Figure 4A and in Figure 4B which is a section on line IV-IV of Figure 4A, each of the outer ends 8a to I la of the switch parts 8 to 11 is opposed to a respective one of the stop portions 16f of the liquid crystal cell position determining member 16. Thus, the outer end 9a of the switch part 9 is urged by its push button (similar to push button 18) against its stop portion 16f when the push button is pressed. In a similar manner, the push buttons associated with the switch parts 8, 10 and 11 are arrested by a corresponding one of the stop portions 16f.

   As a result, a user can easily feel the mode of operation of the switch parts, whereby he is informed that the switch operation has been completed. In addition, the external force for operating the switch parts is arrested by the liquid crystal cell position determining member 16 which is mechanically stronger than the other timepiece parts, so that there is no risk of the other timepiece parts being broken.

   The timepiece case is not shown but it is to be understood that it encloses the module and that all the push buttons, such as push button 18, for operating the switch parts 8 to 11 are mounted for movement in a side wall of the case.

   As described hereinbefore, in the electronic timepiece all of the switch parts are secured to the protective cover, the switch parts are simple in construction, and they can easily be assembled together with any other timepiece parts. In addition, since the external force for operating the switch parts is limited in its effect by the mechanically strong timepiece part which forms the liquid crystal cell position determining member, there is no risk of the other timepiece parts being broken.

   Moreover, the switch parts are stopped in their movement at a given position, so that the user can feel the mode of the switching operation whereby he can correctly operate the switch parts.

   In addition, in accordance with an advantageous feature of the invention, provision may be made of bifurcated connection parts 12 each formed as a spring and each connected to an electrically conductive tube 19 receiving a push button such as push button 18. As a result, if the connection parts 12 are supplied with a voltage, it is possible to apply the voltage through the connection parts 12, tubes 19 and push buttons to the switch parts 8 to 11.

   Such a construction and arrangement of the switch parts and connection parts are very useful in that they permit a rear cover to be formed of a non-electric-conductive material as compared with the prior art electronic timepieces in which the voltage is applied to the switches through the rear cover.

   WHAT WE CLAIM IS: 1. An electronic timepiece comprising a module composed essentially of a liquid crystal cell, a liquid crystal cell position determining member receiving said liquid crystal cell, a circuit substrate having a first face arranged adjacent said member and a protective cover arranged adjacent a second face of said circuit substrate, said second face being opposite said first face, and said protective cover having switch parts secured thereto for controlling the timepiece.
2. 2. An electronic timepiece according to Claim 1, wherein said circuit substrate is provided on said second face with a wiring pattern having contacts, and each of said switch parts is formed of metal sheet and is provided with a first resilient portion directly connected to a respective one of said contacts.
3. 3. An electronic timepiece according to Claim 2, wherein both said liquid crystal cell position determining member and said protective cover are formed of an insulating plastics material, said circuit substrate is formed of ceramics, and each of said switch parts is provided with a second, resilient portion arranged at the periphery of said protective cover, and a push button is provided for each said switch part, each push button being mounted for movement in a side surface of a timepiece case enclosing said module and each push button having an electrically conductive portion, the arrangement being such that when a push button is pushed its electrically conductive portion engages a respective said second, resilient portion to complete a circuit.
4. 4. An electronic timepiece according to

   Claim 2, wherein said liquid crystal cell position determining member p vides a stop portion for each of said switch parts.
5. 5. An electronic timepiece according to Claim 2, wherein, for each said switch part, there is provided a push button having an electrically conductive portion and mounted for movement in a side surface of a timepiece case enclosing said module, and an electrical connection part formed of metal sheet secured to a peripheral portion of said protective cover, the arrangement being such that when a push button is pushed a circuit is completed between said wiring pattern, a said switch part associated with said push button, the electricallyconductive portion of said push button and a said electrical connection part associated with said switch part.
6. 6. An electronic timepiece having a module substantially as hereinbefore described with reference to the accompanying drawings.