GB2353411A

GB2353411A - Multi-contact switch and portable data terminal

Info

Publication number: GB2353411A
Application number: GB0020347A
Authority: GB
Inventors: Satoshi Banno
Original assignee: NEC Corp
Current assignee: NEC Corp
Priority date: 1999-08-18
Filing date: 2000-08-17
Publication date: 2001-02-21
Anticipated expiration: 2020-08-17
Also published as: GB2353411B; JP3259716B2; GB0020347D0; CN1285660A; JP2001056730A

Abstract

A portable data terminal includes a display unit, a key-input section, a key-analysis section and a control unit (Fig. 1). The key-input section includes a plurality of multi-contact key switches. Each of the multi-contact key switches has a plurality of contacts P, N corresponding to a plurality of switch states, and includes an elastic pillar portion, a conductor and concentric contacts on a substrate.

Description

2353411 MULTI-CONTACT SWITCH AND PORTABLE DATA TERMINAL USING THE SAME

Background of the Invention 5 1. Field of the Invention

The present invention relates to a multicontact switch to which a plurality of operation instructions can be allocated, and a portable data terminal using the same.

2. DescriDtion of the Related Art- Conventionally, a key switch having one switch contact is provided for a portable data terminal. The execution of an instruction is controlled through the operation of the key switch. Therefore, it is necessary to increase the number of switches to execute a lot of instructions. As a result, the operation becomes troublesome and an extra mounting space becomes necessary to add the key switch.

Also, for the execution of a plurality of operations by use of such a single key. switch, t here are typically two methods. One method involves pushing of the key switch for a short time or for a long time, so that an operation is executed depending on the pushing time. The other method involves executing an operation depending on whether the key switch is pushed once or twice for a 2 predetermined time. By using these methods, the space in which the key switch should be mounted can be 5 diminished.

In the above conventional methods, the selection of the instruction depends on the pushing time of the single key switch or the number of times the key switch is pushed. Therefore, it is impossible to momentarily detect an operation instruction. Thus, there is no operation until the next instruction is excuted.

In conjunction with the above description, a power supply control system in a portable communication terminal is disclosed in Japanese

La d-Open Patent Application (JP-A-Heisei 1041871). In this reference, the portable communication terminal is composed of a key-input section, and a key-pushing -detecting section for detecting a key operation of the key-input sect-ion. A key-pushing-time calculating section calculates the time for which the key continues to be pushed. A key-input determining section determines operation data based on the detection result by the key-pushing detecting section, the calculation result by the key pushing-time calculating section, terminal status data and a setting condition for the key 3 operation determination. In this way, there is prevented a risk that the power supply is turned off, in a case where a power supply switch is provided near another switchable key. 5 Sun=Lary of the invention Therefore, an object of the preferred embodiments of the present invention is to provide a multi-contact key switch to which a plurality of operation instructions can be allocated.

Another object of the preferred embodiments of the present invention is to provide a multi-contact key switch without any time delay in one key switch, and a portable data terminal using the multi-contact key switch.

In order to achieve an aspect of the present invention, a multi-contact key switch includes a tab, a- pillar portion, a conductor and a substrate. The pillar portion is formed of an elastic member and is coupled to the tab at an upper portion of the pillar portion. The conductor is coupled to the lower surface of the pillar portion. The substrate includes a first contact, a second contact and at least one third contact.

Here, the pillar portion may have a lower portion with a curved surface formed to protrude.

The conductor is attached to the 4 curved surf ace. ' In this case the f irst contact is desirably provided such that the f irst contact first contacts the conductor of the key switch when the key switch is operated. In this case, the second contact and the third contact may be provided in concentric circles such that the second contact is located outside of the first contact and the third contact is located outside of the second contact. Also, it is desirable that a first switch state is defined when the conductor contacts the first and secondcontacts, and a second switch state is defined when the conductor contacts the first and third contacts.

In order to achieve another aspect of the present invention, a portable data terminal includes a display unit, a key input section, a key analysis section and a control unit. The key input section includes a plurality of multicontact key switches. Each of the plurality of multi-contact key switches has a plurality of contacts respectively allocated with a plurality of switch states. The key analysis section detects an operated one of the plurality of multi-contact key switches and.' detects the plurality of switch states of the operated key switch. The plurality of switch states includes a first switch state and at least one second switch state. The control unit controls a display on the display unit based on the detecting results by the key analysis section.

In this case, t.he plurality of switch states may include the first switch state and a plurality of said second switch states. A palette is allocated to each of the plurality of key switches, and the palette includes instructions for the plurality of second switch states, respectively. In this case, an instruct-lon for the first switch state is associated with the instructions for the plurality of second switch states.

Also, the key analysis section outputs a scan signal to the key input section when the first switch state of any of the plurality of key switches is ',established, and receives a response to the scan signal from the key input section, specifies the operated key switch based on the scan signal and the response. Then, the key analysis section detects the first switch state and the second switch state of the operated key switch. In this case, the key analysis section outputs the first switch state"and the second switch state of the operated key switch to the control unit. The control unit changes the display on the display unit based on the first 6 switch state and the second switch state of the operated key switch from the key analysis section.

Also, a cursor movement instruction may be allocated to the first switch state of the operated key switch, and an instruction indicative of a content of cursor movement may be allocated to the at least one second switch state.

Instead, a display instruction for a group of characters may be allocated to the first switch state, and an instruction indicative of A display attribute of a displayed character may be allocated to the at least one second switch state., In this case, it is desirable that the characters of the group are sequentially displayed as the displayed character each time the operated key switch is operated. Also, the displayed character is desirably displayed in a different font based on the at least one second switch state.

Also, each of the, plurality of multi- contact key switches may include a tab, a pillar portion formed of an elastic member and coupled to the tab at an upper portion of the pillar portion, a conductor coupled to the lower surface of the pillar portion, and a substrate including a first contact, a second contact and at least one third contact. In this case, the pillar portion may have a lower portion with a curved I 7 surface formed to protrude, wherein the conductor is attached to the curved surface. Also, the first contact i.s provided such that the first contact first contacts the conductor of the key switch when the key switch is operated. In this case, the second contact and the third contact are desirably provided in concentric circles such that the second contact is located outside of the first contact and the third contact ls located outside of the second contact. Also,-th.e first switch state is desirably defined when the conductor contacts the first and second contacts, and the at least one second switch state is defined when the conductor contacts the first contact and the at least one third contact.

In order to achieve still another aspect of the present a method is provided of changing a display in a portable data terminal using a plurality of multi-contact key switches, wherein each of the plurality of multi-contact key switches has a plurality of contacts respectively allocated with a plurality of switch states, and the plurality of switch states includes a first switch state and at least one second switch state. The method is attained by operating one of the plurality of multi-contact key switches as a specific key switch; by 8 specifying the specif ic key switch in response to an operation of any of the plurality of multicontact key swi.tches; by detecting establishment of the second switch state of the specific key switch to generate a display change instruction; and by changing display on a display unit in response to the display change instruction.

In this case, a character display instruction for a group of characters may be allocated to the first switch state, and an attribute specifying instruction to instruct a display attribute of a displayed character may be allocated to the at least one second switch state. The display change instruction includes the character display instruction and the attributespecifying instruction. In this case, the characters of the, group may be sequentially displayed as the displayed character each time the specific key switch is operated. The displayed character is displayed in a different font in response to the attribute-specifying instruction.

Also, a cursor-movement instruction may be allocated to the first switch state of the operated key switch, and an instruction indicative of a content of cursor movement may be allocated to the at least one second switch state.

9 The display change instruction includes the cursor movement instruction and the instruction.

Brief Description of the Drawings

Preferred features of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which:Fig. 1 is a block diagram showing the structure of a portable data terminal using a multi-contact key switch according to a first embodiment of the present invention; Figs. 2A and 2B are flow charts showing. an operation example of cursor movement in the portable data terminal according to the first embodiment of the present invention; Fig. 3A is a diagram showing the crosssectional structure of the multi- contact key switch of the present invention, Fig. 3B is a plan view of the lower portion of a switch pillar, and'.Fig. 3C is a plan view of a switch contact section on a substrate; Figs. 4A and 4B are key switch matrix circuits using of the multi-contact key switch of the present invention; Figs. 5A to 5D are diagrams of waveforms used f or a key-scanning operation in the present invention; 25 Figs. 6A and 6B are diagrams showing code conversion tables used in the present invention; Fig. 7 is a diagram showing an executable- instruction change table used in the present invention; Figs. 8A and 8B are flow charts showing an operation example f or character input in a second 5 embodiment of the present invention; andy Fig. 9 is a block diagram showing the portable data terminal using the multi-contact key switch according to a third embodiment of the present invention.

Description of the Preferred EmbodIments

Hereinafter, a multi-contact key switch and a portable data terminal using the multi-contact key switches according to the present invention will be described below in detail with reference to the attached drawings.

Fig. 1 is a. block diagram of the structure of the portable data terminal using the multic ontact key switches according to the first embodiment of the present invention. Referring to Fig. 1, the portable data terminal in the first embodiment is composed of a key input section 1, a key analysis section 2, a control unit 3, a memory section 4 and a display.section 5.

The key input section 1 has a key switch group SW01 to SW20 to allow a figure or a character to be inputted by use of a key switch and to move a cursor. The key analysis section 2 analyzes the pushed state of one of the key switches in the. key input section 1, when the key switch is pushed. The memory section 4 stores key palette data describing an operation of each of the key switches in the key input section 1. The control unit 3 carries out the processing and control of various kinds of operations in the portable data terminal. Also, the control unit 3 compares key data analyzed by the key- analysis section 2 and the key palette data stored in the memory section 4, to issue an instruction to be executed. The display section 5 receives the instruction from the control unit 3 to carry out the display of the figure and/or character, and the movement of the cursor.

The key input section 1 has a group of multi-contact key switches SWO1 to SW20, each of which has the structure shown in Figs. 3A to 3C.

Each key switch is a pushing-type key switch.

When the key switch is pushed, the conductor plane provided for the lower surface of a key switch pillar contacts a section of key switch contacts so that the key switch is turned on.

As shown in Fig. 3A, in the multi-contact key switch of the present invention, a tab is provided on the key-switch pillar. The key-switch 12 pillar is formed of a flexible and homogeneous elastic material. The lower portion of the keyswitch pillar protrudes and is curved to have an arc portion with respect to the key-switch pillar center. This curved surface is covered with a conductor material, as shown in Fig. 3B.

A section of switch contacts is provided on a substrate below the keyswitch pillar, as shown in Fig. 3C. A key-switch contact P is arranged on the substrate directly below the key--switch pillar center. The keyswitch contacts N are arranged in a concentric-circle manner to surround the key-switch contact P as a center. Thus, when the key switch is pushed, the conductor plane of the key-switch pillar first contacts the switch contact P and then the keyswitch contacts N, so that the key switch is turned on.

The key-switch contacts N are provided in the concentric-circle manner to provide a plurality of functions for the single-key switch. The key-switch contacts N are grouped into an A group of switch contacts N (one in this example) and a B group of switch contacts N. The A group of switch contact N is a contact just outside the switch contact P. The B group of switch contacts N are contacts B1 to B3 outside of the A group 13 switch contact N.

Also, signal lines are connected with the respective switch contacts, as shown in Fig. 3C. The signals IN1 to IN4 are allocated to the switch contact P. The signals OUT1 to OUTS are allocated for the A group of switch contact N. Signals Bl, B2 and B3 are allocated to the B group of switch contacts N, in order from inside the concentric circles.

An example of the matrix structure for the whole key switches is shown in Figs. 4A and 4B. In this example, the total number of key switches of SW01 to SW20 is 20. For the multi-contact key switches of the present invention, the matrix structure is composed of a first key switch matrix and a second key switch matrix. The first key switch matrix is for the switch contact P and the A group switch contact N, and the second key switch matrix is f or the. B group switch contacts N.

Signals IN1 to IN4 shown in Figs. 5A to 5D, are supplied to the multicontact key switches SW01 to SW20 of the key input section 1, as shown in Figs. 4A and 4B. The low-ldvel timing is shif ted or scanned between the signals IN1 to IN4. If any of the key switches SW01 to SW20 is not pushed, signals OUT1 to OUT5 of a high level 14 are outputted. Also, signals Bl to B3 of the high level are outputted. When any of the key switches SWO1 to SW20 is. pushed, one of the signals OUT1 to OUT5 becomes a low level. When the key is further pushed, at least one of the signals B1 to B3 becomes a low level.

Figs. 2A and 2B are f low charts to show a cursor movement operation when the multi-contact key switches of the pres.ent invention are applied to movement of a cursor in up and down direction"s and left and right directions. For example, (upward direction)" movement instruction is allocated to the key switch SWO1, "I (downward direction)" movement instruction is allocated to the key switch SW02, "-I-- (left direction)" movement instruction is allocated to the key switch SW03. and (right direction)" movement instruction is allocated to the key switch SW04.

The operation when the cursor is moved in a downward direction in the portable data terminal will be described with reference to Figs. 2A and 2 B. First, to move the cursor in the down direction, the key switch SW02of the key input section 1 is pushed or operated. When the key switch is pushed, the pillar conductor of the key switch SW02 first contacts the switch contact P.

Moreover, when the key switch is further pushed, the key switch pillar conductor contacts the A group switch contact N (SI: Yes).

The key analysis section 2 detects the ON state of the A group key switch. If there is no key interrupt (S2: No), the key analysis section 2 outputs the signals IN1 to IN4 shown in Figs.

5A to 5D to the key input section 1. Thus, a key scanning operation is started ( S19 Because the A group switch contact for the key switch SW02 contacts the pillar conductor of the key switch SW02, OUT(5-1) = (1, 1, 1, 1, 0) is outputted as the signals OUT from the key input section 1 to the key analysis section 2 for the key scanning operation. It should be noted that OUT(5-1) means signals OUT5 to OUT1, and the sameis meant in the following description.

The key analysis section 2 analyzes which of the key switches SWO1. to SW20 has been pushed, from the signals IN1 to IN4 outputted from the key analysis section 2 and the signals OUT1 to OUT5 supplied from the key input section 1 (S3). Because OUT(5-1) = (1, 1, 1, 1, 0) is supplied for this time when IN(4-1) = (1, 1, 0, 1) is outputted, the key analysis section 2 detects the key switch SW02 as the pushed key.

At this time, the states of the B group 16 switch contacts are also supplied to the key analysis section 2 as the signal B1 to B3. For example, when none of the B group switch contacts contacts the pillar conductor of the key switch, B(3-1)=(l, 1, 1) is obtained. The key analysis section 2 outputs signals D(6-0) to the control unit 3 based on the inputted signals OUT and the signals B (S4) as a key switch data. A correspondence relation between the signals D(6- 0) and the signals OUT and B are set as shown in Figs. 6A and 6B.

When more than one of the plurality of key switches SWO1 to SW20 in the key input section 1 are pushed at a same time so that the pushed key switch can not be uniquely specified, the key analysis section 2 analyzes it as an invalid key input, and outputs D(4-0) = (0, 0, 0, 0, 0). Because the pushed key switch is detected to be SW02 from the signals OUT inputted to the key analysis section 2 in this example, D(4-0) = (0, 0, 0, 1, 0) is outputted to the control unit 3. When it is supposed that any of the B group switch contacts does not contact the pillar conductor of the key switch SW02, D(6-5) = (0, 0) is outputted to the control unit 3, because B(31) = (1, 1, 1).

At a step S5, the control unit 3 first 17 determines whether or not D(4-0) is (0, 0, 0, 0, 0), from the inputted key switch data D(6-0). In other words, the control unit 3 determines whether or not the invalid key input occurs in the key input section 1 (S5). If the invalid key input has occurred so that (0, 0, 0, 0, 0) is supplied to the control unit 3 as D(4-0) (S5: Yes), (0, 0, 0, 0, 0, 0, 0) is substituted for X(7-1) (S17). Then, the.key scannIng operation is stopped (S18). After the key scanning operation is stopped, the control newly returns back to the key-input waiting state. X(7-1) is internal data of the control unit having (0, 0, 0, 0, 0, 0, 0) as the initial value.

In the operation example, because (0, 0, 0, 1, 0) is supplied the control unit 3 as D(4-0) (S5: No), the control unit 3 next com"pares D(4-0) with X(5-1) (S6). The data are not coincident with each other (S6: No), because (0, 0, 0, 0, 0) is supplied to X(5-1) as the initial value at present. When the data are not coincident with each other, D(6-0) is substituted for X(7-1) and is stored in the memory section 4 (S7 and S8). After that, the data of X(7- 1)lis inquired with the key palette data which is stored in the memory section 4 (S9). An operation instruction is outputted in accordance with the data of X(7- 18 6) (S10), and is executed (S11 to S14).

The key palette data is data which describes the r.ole of each key, or an executable instruction, or indicates an attribute or content of the instruction defined based on the contact between the switch contact P and the A group switch contact N. A plurality of key palette data are provided for the palette in accordance with the kinds of the executable nstr uct ons. Fig. 7 shows an example of the key palette data. In this example, three kinds of key palette data are provided for the cursor movement, the character input, and the alphanumeric character input. For example, it is possible for the used palette to be switched from the palette for the character input to the palette for the alphanumeric character input in accordance with the operation of a mode key switch. In this way, the key setting can be freely switched.

In the operation example, because the palette for the cursor movement is allocated for SW04 from SW01, a cursor movement instruction is executed when it is detected that any of the key switches SW01 to SW04 is pushed. Also, the concept of a "level" can be provided for the key palette so that it becomes possible to set a plurality of executable instructions to one key.

19 The selection of the level is carried out based on the data of X(7-6) corresponding to D(6-5).An instruction of A first level is carried out in case of X(7-6) (0, 0), and an instruction of a second level is carried out in case of X(7-6) (0, 1). Also, an instruction of a third level is carried out in case of X(7-6) = (1, 0), and an instruction of a fourth level is carried out in case of X(7-6) = (1, 1)...

Because X(7-1) = (0, 0, 0, 0, 0, 1, 0) at- present, the control unit 3 carries out an instruction of the first level that the cursor is moved in the down direction by one step. As a result, the cursor displayed on the display section 5 is moved in the down direction by one step (S11).

After, the processing is ended, the next data process is immediately carried out (S1 to S4). If the next data D(6-0) which has been inputted to the control unit 3 is not changed from the previous data (SS, S6.. Yes, and S15: Yes), no operation is carried out (S16) and the process for the next D(6-0) is started (S1 to S5).

If the pushed key switch is the same and only the B group switch contacts arechanged, that is, when the pushing operation of the key switch is continued and further the pushing pressure is applied to the key switch SW02, (1, 1 0) 1, 0, 0.) or ( 0 0 0) is supplied to the key analysis section 2 as B(3-1) based on the number of B group switch contacts N depending on the pressure to the key switch. Therefore, the value of X(7-6) is substituted and is stored (S8), because only D(6-5) changes without change of D(4-0) (S6, S6: Yes, and S15; No). An operation of either of the second level (cursor low-speed continuous movement) (S12), the third level (cursor high-speed continuous movement) (S13), the fourth level (cursor movement to the last) (S14) is carried out in accordance with the data D(6-5).

Thereafter, the above operation is repeated in accordance with the pushing pressure of the key switch SW02.

In this. way, by only changing the pushing pressure to the key switch, the movement speed of the cursor in the down direction can be controlled by use of only one key switch SW02. When the pushing state of the key switch to the A group switch contact is cancelled (S1: No), the values of X(7-1) are initialized (S17) and the scanning operation is stopped (S18). Then, the control returns to the key switch input wait 21 s t a t e Figs. 8A. and 8B are flow charts showing the operation of the portable data terminal according to the second embodiment of the present invention. , in which a character is inputted. Fig. 9 is a block diagram showing the structure of the portable data terminal according to the second embodiment of the present invention.

Referring to Fig..9, the basic operation of the portable data terminal in the second embodiment is the same as the above-described cursor movement operation. However, the steps S21 to S28 in Figs. 8A and 8B are new. A signal SWDET is outputted from the key analysis section 2 to the control unit 3 when the start of the key scanning operation is instructed, as shown in Fig. 9.

A character input palette shown in Fig. 7 is applied to the key switches SWOS to SW15. In this palette, characters are allocated to the key switch in units of groups. For example, "7".

@'f 'E, "-M", and "t" ("a", "i", soul#, "e" and of o" of Japanese Katakana characters) are allocated to the key switch SW05 as a character group, and these characters are displayed in order through the pushing operation of the key switch SWOS. Also, "t", "7", and "J" 22 "ka" "ki" "ku" "ke" and "ko" of Japanese Katakana characters) are allocated to the key switch SW06 as a character group, and these characters are displayed in order through the pushing operation of the key switch SW06. Also, st; If, lliZ If and "\ If (11sa 11, Ilsill, lisull, "se" and "so" of Japanese Katakana characters) are allocated to the key switch SW07 as a character group, and the.se characters are displayed in order through the pushing operation of the key switch SW07. Hereinafter, characters are allocated to the key switches in the same way for each of the character groups.

It is supposed that a character is now inputted to the position where no character is displayed on the display section 5. In this case, if the key switch' SW05 is pushed so that the A group key switch is turned on (S1: Yes and S2: No), the key analysis section 2 outputs the signal SWDET to the control un t 3 (S21). The control unit 3 receives the signal SWDET to set the flag S in the control unit to "1". The initial value of the f lag S is " 0 If. Also, the key scanning operation is started X S1 9) - The key scanning operation is the same as the operation in the first embodiment. Because the A group switch contact N for the key switch SW05 contacts the pillar conductor of the key switch SW05 for this time, the signals OUT as OUT(5-1) = (1,.1, 1, 0, 1) are outputted from the key input section 1 to the key analysis section 2 5 for the key scanning operation.

The key analysis section 2 analyzes which of the key switches-has been pushed, from the signals IN outputted from the key analysis section 2 and the signal.s OUT inputted from the key input section 1 (S3). For this time, because OUT(5-1) = (1, 1, 1, 0, 1) is inputted, and IN(41) = (1, 1, 1, 0) is outputted, the key analysis section 2 detects the key switch SW05 as the pushed key switch.

After the key switch data D(6-0) is outputted to the control unit 3 (S3-S4, and S5: No), the control unit 3 confirms whether or not any character is already displayed in the position where the character should be displayed (S23). If not displayed, after the data of D is substituted for X (S6, and S7), the flag is reset to "0" (S28). Then, a character display instruction is carried out (S9 to S14).

More specifically, when tthe A group switch contact N contacts the pillar conductor of the key switch SWO5 so that D(6-0) = (0, 0, 0, 0, 1, 0, 1) is inputted to the control unit 3, the 24 control unit 3 controls the display section 5 to display the character " 7 " as the first character of the character group f or the key switch SW5 in accordance with the instruction of the first level (capital-size Katakana character representation) based on the key switch data. In other words, is displayed.

If this state is maintained (S1 to S5 and S23: Yes), the key switch data is not changed.

Also, the flag S is set to "0". Therefore, the next display process is not carried out (S24, S25: Yes, S26: No, S15: Yes and S16). The, displaysection 5 remains in the state in which the character " is displayed.

Next, it is supposed that the pushing pressure of the key switch SWOS is more strengthened in this condition and the key analysis section 2 outputs D(6-0) = (1, 1, 0, 0, 1, 0, 1) to the control unit 3 (S1 to S4, S5:

No) In this case, the character remains in the displayed condition. Also, only D(6-5) of the key-switch data is different from the last time (S23, S24, and S25. No). Therefore, the control unit 3 issues the instruction to change the displayed character into the character of the fourth level (S7 to S10). In this way, the smallsize Hirakana character " J5 " is displayed on the display section 5 (S14).

When the key-sw tch pushing operation is ended ( S1: No) the key scanning operation is stoPped, and the X value and the 5 value are reset. Then, the control advances to the keyinput waiting state (S17, S18 and S22). In this state in which the small-size Hirakana character J5 is displayed, lt: is supposed that the key switch SW5 is pushed onc.e again ("D(6-0) = (0, 0, 0 0, 1, 0, 1) is inputted to the control unit 3 (S1: Yes, S2: No, S21. S19, S3 to S4, andS5:

No).

The character " J5 " inputted previously exists in the position (S23: Yes). Also, the key switch SW05 of the character group to which this displayed character belongs is pushed (S24 and S25: Yes). In addition, the flag S is set to"1" (S26: Yes) Therefore, the control unit 3 selects the next character "-f " of the characters in the same character group (S27) so that the capital sj-ze Katakana character "-f is displayed on the di-splay section 5 instead of the small-size Hi-rakana character " J5 S7 and so on) When a mode key newly-provided for the key switch SW16 is operated, the key-switch allocation palette is changed to the alphanumericcharacter input palette. Thus, it. becomes 26 possible to switch between the c.apital-size alphanumeric character, the small-size alphanumeric character, and the italic character, in the same way as described above.

Also, when the interval between the concentric circular switch contacts is made wider on the substrate, that is, when the interval between the A group switch contact N and the B group switch contact N i.s made wider than the interval of the B group switch contacts, the region where the instruction of the first level can be carried out (the key-switch pushing region) is made wider than for the instruction of another level so that the differentiation of the level can be attempted.

In the present invention, as for the switch contact, the switch contact is increased as the B group switch contacts N in addition to the A group switch contact N in the conventional example. Accordingly, means for adding the executable instructions by the number of B group switch contacts is provided. Therefore, the execution of a plurality of operation instructions can be made possible with one key switch and the number of key switches can be largely reduced.

Also, the elastic material member is used 27 to have the project portion in the key-switch pillar lower portion center for the key-switch pillar to contact the switch contacts P and N. Also, the switch contacts N are arranged on the concentric circles around the switch contact P. Also, means for detecting the change of the key- switch pushing pressure with change of the substrate contact with the key- switch pillar is provided. Therefore, the executable instruction can be changed in accordance with the pushing pressure of the key switch without a temporal delay.

While the present invention has been described in its preferred embodiments, it is to be understood that the words which have been used are words of description rather than limitation, and that changes may be made to the invention without departing from its scope as defined by the appended claims.

Each feature disclosed in this specification (which term includes the claims) and/or shown in the drawings may be incorporated in the invention independently of other disclosed and/or illustrated features.

The text of the abstract filed herewith is repeated here as part of the specification.

A portable data terminal includes a display unit, a key-input section, a key-analysis section and a control unit. The key-input section includes a 28 plurality of multi-contact key switches. Each of the plurality of multi-contact key switches has a plurality of contacts respectively allocated with a plurality of switch states, and includes an elastic pillar portion, a conductor and the concentric- circular contacts on a substrate. The key- analysis section detects an operated one of the plurality of multi- contact key switches and detects the plurality of switch states of the operated key switch. The plurality of switch states includes a first switch state and at least one second switch state. The control unit controls a display on the display unit based on the detecting results analyzed by the keyanalysis section.

29

Claims

CLAIMS:

A multi-contact key switch comprising a flexibly-deformable member and at least three selectively-connectable conductors, connection between the conductors being selectively established according to the degree of deformation of the flexible member.
2. The multi-contact key switch according to claim 1, wherein the flexibly-deformable member is a pillar having a conductive surface on its one end, and wherein the three selectively- connectable conductors are a first contact, a second contact and at least one third contact on a substrate with which the conductive surface comes into contact.
3. The multi-contact key switch according to claim 2, wherein the conductive surface is curved.
4. The multi-contact key switch according to claim 2 or 3, and also comprising a tab, coupled to the other end of the pillar.
5. A multi-contact key switch comprising: a t ab; a pillar portion formed of an elastic member and coupled to said tab at an upper portion of said pillar portion; a conductor coupled to said lower surface of said pillar portion; and, a substrate including a first contact, a second contact and at least one third contact.
6. The multi-contact key switch according to claim S, wherein said pillar portion has a lower portion with a curved surface formed to protrude, wherein said conductor is attached to said curved surface.
7. The multi-contact key switch according to claim 2 or 6, wherein said first contact is provided such that said conductor of said key switch first contacts said first contact when said key switch is operated.
8. The multi-contact key switch according to claim 7, wherein said second contact and said third contact are provided in concentric circles such that said second contact is located outside of said first contact and said third contact is located outside of said second contact.

31
9. The multi-contact key switch according to claim 7 or 8, wherein a first switch state is defined when said conductor contacts said first and second contacts, and a second switch state is defined when said conductor contacts said first and third contacts.
10. A portable data terminal comprising: a display unit; a key input section. including a plurality of multi-contact key switches, each of said plurality of multi-contact key switches having a plurality of contacts respectively allocated with a plurality of switch states; a key analysis section detecting an operated one of said plurality of multi-contact key switches and detecting said plurality of switch states of said operated key.switch, wherein said plurality of switch states includes a first switch state and at least one second switch state; and.

a control unit controlling a display on said display unit based on the detecting results by said key analysis section.
11. The portable data terminal'. according to claim 10, wherein: said plurality of switch states includes said first switch state and a plurality of second switch states; 32 a palette is allocated. to each of said plurality of key switches; and, said palette includes instructions for said plurality of second switch states, respectively.
12. The portable data terminal according to claim 11, wherein an instruction for said first switch state is associated with said instructions for said plurality of second switch. states.
13. The portable data terminal according to any of claims 10 to 12, wherein said key analysis section outputs a scan signal to said key input section when said first switch state of any of said plurality of key switches is established, receives a response to said scan signal from said key input section, specifies said operated key switch based on said scan signal and said response, and detects said first switch state and said second switch state of said 10 operated key switch.
14. The portable data terminal according to claim 13, wherein:said key analysis section outputs said first switch state and said second switch state of said operated key switch to said control unit; and.,, 5 said control unit changes said display on said display unit based on said first switch state and said 33 second switch state of said operated key switch from said key analysis section.
15. The porta, ble data terminal according to claim 14, wherein'-a cursor movement instruction is allocated to said first switch state of said operated key switch; and an instruction indicative of a content of It.7 cursor movement is allocated to said at least one second switch state.
16. The portable data terminal according to claim 14, wherein:a display instruction for a group of characters is allocated to said first switch state,; and.an instruction indicative of a display attribute of a displayed character is allocated to said at least one second switch state.
17. The portable data terminal according to claim 16, wherein said characters of said group are sequentially displayed as said displayed character each time said operated key switch is operated.
18. The,portable data terminal according to claim 16 o r 17, wherein said displayed "character is displayed in a different font. based on said at least one second switch state.

34
19. The, portable data terminal according to any of claims 10 to 18,. wherein each of said plurality of multi-contact key switches comprises:

a tab; a pillar portion formed of an elastic member and coupled to said tab at an upper portion of said pillar portion; a conductor coupled to said lower surface of said pillar portion; and', a substrate including a first contact, a second contact and at least one third contact.
20. The portable data terminal according to claim 19, wherein said pillar portion has a lower portion with a curved surface formed to protrude, wherein said conductor is attached to said curved surface.
21. The portable data terminal according to claim 20, wherein said first contact is provided such that said first contact first contacts said conductor of said key switch when said key switch is operated.
22. The portable data terminal according to claim 21, wherein said second contact and said third contact are provided in concentric circles such that said second contact is located outside of said first contact and said third contact is located outside of said second contact.
23. The portable data terminal according to claim 21 or 22, wherein said first switch state is defined when said conductor contacts said first and second contacts, and said at least one second switch state is defined when said conductor contacts said first contact and said at least one third contact.
24. A method of changing a display in a portable data terminal using a plurality of multi-contact key switches, wherein each of said plurality of multicontact key switches has a plurality of contacts respectively allocated with a plurality of switch states, and said plurality of switch states includes a fi-rst switch state and at least one second switch state, said method-comprising:

operating one of said plurality of multi contact key switches as a specific key switch; specifying said specific key switch in response to an operation of any of said plurality of multicontact key switches; detecting establishment of said second switch state of said specific key switch' to generate a display change instruction; and., changing display on a display unit in response to said display change instruction.

36
25. The method according to claim 24, wherein a character display instruction for a group of characters is allocated to said first switch state, and an attribute -specifying instruction to instruct a display attribute of a displayed character is allocated to said at least one second switch state, and wherein said display change instruction includes said character display instruction and said attribute- specifying instruction.
26. The method according to claim 25, wherein said characters of said group are sequentially displayed as said displayed character each time said specific key switch is operated.
27. The method according to claim 26, wherein said displayed character is displayed in a different font in response to said attribute-specifying instruction.
28. The method according to claim 25, wherein a cursor-movement instruction is allocated to said first switch state of said operated key switch, and an instruction indicative of a content of cursor movement is allocated to said at least one second switch state, and wherein said display change instruction includes said 37 cursor-movement instruction and said content-indicating instruction.
29. A multi-contact key switch substantially as herein described with reference to and as shown in the accompanying drawings.
30. A method of changing a display in a portable data terminal using a plurality of multi-contact key switches, the method being substantially as herein descried with reference to and as shown in the accompanying drawings.