US3701064A

US3701064A - Push-button switch

Info

Publication number: US3701064A
Application number: US212096A
Authority: US
Inventors: Ryohei Kinoshita; Masami Ishizawa
Original assignee: Fujitsu Ltd
Current assignee: Fujitsu Ltd
Priority date: 1970-12-29
Filing date: 1971-12-27
Publication date: 1972-10-24
Anticipated expiration: 1989-10-24
Also published as: DE2165384B2; DE2165384C3; DE2165384A1

Abstract

This disclosure relates to a push-button switch comprising a housing provided with a support means for supporting a magnetic member, a reed switch element fixedly and vertically positioned in the housing, a lower spring contained in the housing, a magnet mounted on the lower spring which is capable of moving up and down with respect to the reed switch while its upward movement is restrained by the support means and also said magnet is capable of being attracted to the magnetic member in the ordinary state, a pusher capable of moving up and down, a first upper spring applied to the pusher member at its one end, and mounted on the magnet at its other end and a second upper spring also mounted on the magnet and vertically distant from the pusher at a first pushed down displacement of the pusher whereby, before a state in which the pushed down force applied to the pusher overcomes the critical resistance of the sum of the initial resilient force of the lower spring and the magnetic attractive force acting between the support means and the magnet, whereby the magnet carried out the downward snap action thus forming a magnetic field which operates the reed switch, firstly the pusher undergoes the first pushed down displacement while being opposed by the resistance from the first upper spring so that the pushing down force on the pusher equals the force of the sum of the resilient force of the first upper spring and the initial resilient force, and then, the pusher is further pushed to a critical displacement where the pushed down force overcomes the above-mentioned critical resistance force.

Description

Primary E xaminerRoy N. Envall, Jr. Attorney-Allan Ratner 0 United States Patent 1 3,701,064 Kinoshita et al. 1 Oct. 24, 1972 [54] PUSH-BUTTON SWITCH [57] ABSTRACT [72] Inventors: Ryohei Kinoshita; Masami Ishizawa, This disclosure relates to a push-button switch comb th f Ka ki, Japan prising a housing provided with a support means for a supporting a magnetic member, a reed switch element [73] Assgnee: Fujitsu Limited Kawasah'sh" fixedly and vertically positioned in the housing, a Japan lower spring contained in the housing, a magnet [22] Fil d; D 27, 1971 mounted on the lower spring which is capable of moving up and down with respect to the reed switch while [21] Appl-No-i 212,096 its upward movement is restrained by the support means and also saidmagnet is capable of being at- [30] Foreign Application priority Data tracted to the magnetic member in the ordinary state, a pusher capable of moving up and down, a first upper Dec. 29, 1970 Japan ..45/l33336 Spring applied to the pusher member at its one end DEC. 30, Japan and mounted on the magnet at its other end and 3 Dec. 31, Japan second upper pring 3150 mounted on the magnet and Dec. 31, Japan vertically distant from the pusher at a first pushed down displacement of the pusher whereby, before a [52] U.S. Cl. ..335/205, ZOO/67 F state inwhich the pushed down force applied to the [5 l Int. Cl. ..H0lh 5/02 pusher overcomes the critical resistance of the sum of [58] Field of Search ..335/205, 206, 207; 200/67 F the initial resilient force of the lower spring and the magnetic attractive force acting between the support [56] References Cited means and the magnet, whereby the magnet carried out the downward snap action thus forming a mag- UNITED STATES PATENTS netic field which operates the reed switch, firstly the 3,310,762 3/1967 Goetz ..335/205 Pusher undergoes the first pushed down displacement 3,465,271 9/1969 Koepke ..335/205 While being Opposed by the resistance from the first 3,644,855 2/1972 Cherry et al ..335/205 PP Spring that the Pushing down force the pusher equals the force of the sum of the resilient force of the first upper spring and the initial resilient force, and then, the pusher is further pushed to a critical displacement where the pushed down force overcomes the above-mentioned critical resistance force.

10 Claims, 29 Drawing Figures P'A'IENTEMM 2 m2 3. 701. 064

SHEET 01 0F 12 PATENTEDnm 24 I972 3. 701. 064 sum 020F 12 PATENTED 0m 24 m2 SHEET 03 0F 12 Gm 89m PATENTED our 24 1912 saw on or 12 minimum 24 m2 3.701. 064

SHEET DSUF 12 Fig. 6

w P. 55 LOWER SPRING 8 .(PRIOR ART) I GNET SNAPPING ACTION CHARACTERISTICS 21'. I

(f) I CHANGE OF ATTRACTIVE "FORCE BETWEEN MAG- FIRST UPPER SPRING D'SPLACEMENT (mm) TIME PATENTEDMI 24 1972 SHEET 08 0F 12 m mm F r: c a

& m m 8 PATENTEnucrzuszz Q 3,701,064 sum 1DOF 12 PRIQR ART PRIOR ART Fig. /2 Fig. /2b 7 [7 i 'A 4 VIA-'11),

Fig. I30

' PATENTEDwwsn 3.701.064

' SHEET llUF 12 PATENIED BT 370L064 SHEET 120? 12 1 PUSH-BUTTON SWITCH DESCRIPTION OF THE INVENTION This invention relates to a push-button switch and more particularly relates to a snap switch employing a magnetic reaction element e.g. a reed switch as a switching element.

There is the conventional push-button switch in which a magnet is attracted to a keeper member made of magnetic material in the non-operated ordinary state while being supported between an upper and a lower spring, and a well-known conventional reed switch element is disposed so as to be cooperable with the magnet, whereby resilient force is firstly stored in the upper spring when an upper key top member provided for switching operation is pushed down while being opposed by the upper spring and secondly, as soon as the resilient force becomes strong enough to overcome the magnetic attractive force between the magnet and the keeper member, this magnet immediately disconnects itself from the keeper member so as to give a downward snap action while bearing against the lower spring, and as a result, the contact of the reed switch element operates.

In this kind of conventional push-button switch, the following drawbacks are encountered.

1. As it is not clearly recognizable when the snap action starts, owing to the smooth pushing in force, the operator of the push-button switch feels a kind of psychological anxiety and as a result, becomes fatigued.

2. As the magnet rebounds from the lower spring after the snap action causing a variation of the magnetic force acting upon the switching element, chattering of the contact of the switching element takes place which not only shortens the life of the contact but also, interferes with the related electronic equipment.

3. Because of large leakage of magnetic flux from the magnet, magnetic interference occurs between neighboring push-button switches while degrading the functional characteristics of the respective push-button switches and as a result, in the worst case a switching element fails to return to its original state even after the magnet has returned to its original state where the magnet is once more, attracted to the keeper member.

4. The conventional push-button switch can not be mass produced due to its structure and therefore, push-button switches satisfactory in manufacturing cost, performance and equality can not be obtained.

The object of the invention is to provide a push-button switch which has an improved pushing touch or keying touch from the human engineering point of view while maintaining the characteristics of the snap switch.

Another object of the present invention is to provide a push-button switch which is provided with means to prevent chattering of the contact of the switching element by reducing the rebound of the magnet to the minimum amount possible.

A further object of the present invention is to provide a push-button switch having an arrangement wherein the key top member is easily changeable and can never be taken off by a rebound action when it is strongly pushed down because the key top member of the push-button switch is usually a character key, a numeral key or a symbol key as required, and is required to be optionally changeable without difficulty.

Another object of the present invention is to provide an economical push-button switch with a lamp indication composed of a switch unit and a lamp indication unit which is changeably mounted on the switch unit and is capable of being in several kinds of indicating states in order that it may be distinguishable in the case where there are a number of push-button switches on the control panel of an electronic equipment.

Still another object of the present invention is to provide a push-button switch which is easily produced and assembled.

A push-button switch according to the present invention comprises a housing provided with a support means for supporting a magnetic member, a reed switch element fixedly and vertically positioned in the housing, a lower spring member contained in the housing, a magnet mounted on the lower spring which is capable of moving up and down with respect to the reed switch while its upward movement is restrained by the above-mentioned support means and also said magnet is capable of being attracted to the magnetic member in the ordinary state, a pusher member eapable of moving up and down, a first upper spring applied to the pusher member at its one end, and mounted on the magnet at its other end and a second upper spring also mounted on the magnet and vertically distant from the pusher member at a first pushed down displacement of the pusher member whereby before a stage in which the pushed down force applied to the pusher member overcomes the critical resistance of the sum of the initial resilient force of the lower spring and the magnetic attractive force acting between the support means and the magnet, whereby the magnet carries out the downward snap action thus forming a magnetic field which operates the reed switch, firstly the pusher undergoes the first pushed down displacement while being opposed by the resistance from the first upper spring so that the pushing down force on the pusher member equals the force of the sum of the resilient force of the first upper spring and the initial resilient force, and then, the pusher is further pushed to a critical displacement where the pushed down force over comes the above-mentioned critical resistance force.

Further objects, features and advantages of the present invention will be apparent from the ensuing descriptions with reference to the accompanying drawings wherein:

FIG. 1 is a schematic front view of a conventional push-button switch;

FIG. 2 is a perspective view of a push-button switch according to the present invention;

FIG. 3 is a partial breakdown side view of a push-button switch according to the present invention illustrating the main body and a key top member which is positioned so as to cover the main body;

FIG. 4(a) and FIG. 4(b) are side views of a push-button switch of the present invention in which FIG. 4(a) illustrates the process of mounting the key top member to the main body, while FIG. 5(b) illustrates the process of removing the key top member from the main y;

FIG. 5(a) to FIG. 5(e) are sectional views of a pushbutton switch of the present invention which illustrates the internal arrangement of the push-button switch and several operating states or stages of the push-button switch;

FIG. 6 is a diagram illustrating the relationship between the pushing down force and the displacement of the pusher member of push-button switches according to the prior art and of the present invention;

FIG. 7(a) and FIG. 7(b) are diagrams illustrating the difference between the prior art and the present invention in the rebounding action of the magnets of the respective push-button switches;

FIG. 8 is a partially cut out perspective view of the housing and reed switch element assembly of a push button switch of the present invention;

FIG. 9(a) to FIG. 9(d) are illustrative views in a continuous molding process of a part of a push-button switch according to the present invention;

FIG. 10 is a side view of the main body of a push-button switch illustrating a different side from FIG. 3;

FIG. 11 is a perspective view of a preferred embodiment of a magnetic material holding means of a pushbutton switch of the present invention and an attaching plate member to which the push-button switch is attached;

FIG. 12(a) and FIG. 12(b) are schematic illustrative views showing opening and closing states of a reed switch element according to the prior art, respectively;

FIG. 13(a) and FIG. 13(b) are schematic illustrative views showing opening and closing states of a reed switch element according to the present invention, respectively;

FIG. 14 is a perspective view ofa push-button switch with lamp indication of the present invention in the state where the key top member is removed;

FIG. 15(a) to FIG. 15(c) are partially cut out perspective views of a lamp indication unit of the present invention illustrating its assembly process from the respective members to the completed unit.

Referring to FIG. 1 which shows a typical arrangement of the conventional push-button switch, reed switch element 2 is arranged in the inside of housing 1 of the push-button switch, and operates in response to a vertical movement of magnet 3. This magnet 3 is positioned between and supported by an upper spring 5 and a lower spring 6 and is attracted to a keeper-plate 7. Reference numeral 4 is a key top member which is capable of being pushed down so that magnet 3 moves downward so as to close the reed switch element 2 at reed pieces 8 of the element 2 as shown in FIG. 1(b).

A push button switch according to the present invention will now be explained.

Referring to FIG. 2 and FIG. 3, a key top member 40 and a push-button switch main body are shown, respectively. This key top member 40 may generally be a character key, numeral key or a symbol key, and is removably fitted to the main body 50 as shown in FIG. 2

At both side walls of housing 51 of the main body so, projections 70 are formed, while in the key top member 40 engaging pawls 41 are formed which engages with the above-mentioned projections 70 of housing 51 as shown in FIG. 3.

As is seen from FIG. 3, projections (only one of which is shown) are formed in a shape having a lower face 71, left and right hand side faces 73, 73 spaced a distance d apart and a top face 75 provided with inclining faces 77 at both left and right hand side portions of the top face 75, respectively.

The pawls 41 of key top member 40 for engaging with projections 70 are formed in the same thickness as that of the other portions of key top member 40.

Claws 45 of pawls 41 which are engageable with the lower face 71 are formed at the lower ends of resilient and flexible supporting portions 42 which are placed in a state independent of the other portions of the key top member 40 by arranging slots 46 and spaces 47 so as to provide lateral flexibility. The spaces 47 on both sides of key top member 40 have respective widths slightly larger than the above-mentioned width d of projections 70. A pair of

claws

45, 45 on each side of key top member 40 are formed by a downwardly expanded inner margins 43, 43 and a pair of top margins 44, 44 which are provided with downwards and inwards descending slopes as shown in FIG. 3.

A support member 59 for supporting a magnet (not shown) a pusher 57, and a spring 55 shown in FIG. 3 will be explained later.

In the above arrangement of main body 50 and key to top member 40, when the key top member 40 is to be assembled to the main body 50, the key top member 40 is firstly positioned on the top of main body 50 and then, is pushed downwards. As a result, the pair of inner margins 43, 43 of the pair of

claws

45, 45 are brought into contact with and are guided by the pair of inclining faces 77 of each projection 70 so as to laterally expand the supporting

portions

42, 42 as shown by chain lines in FIG. 4(a) and accordingly, the top margins 44 of claws 45 can slip into an engagement with each lower marginal face 71 of each projection 7 0.

In the assembled state, key top member 40 is capable of carrying out an up and down free movement over a vertical distance predetermined and limited by spaces 47, that is to say, the upward movement of key top member 40 is limited by engagement of the top margins 44 of claws 45 with lower face 71 of projections 70 so as to prevent the member 40 from coming off.

Moreover, it the elasticity of supporting portions 42; 42 is appropriate, key top member 40 can not come off, even if it carries out a violent restoring reaction under the force of restoring springs (not shown) contained in the main body 50 after the push-button switch has been pushed by the operator.

Also, removal of key top member 40 from the main body 50 is easily carried out by applying a slight pulling force to key top member 40.

This is because the top margins 44 of claws 45 are formed with inwards descending slopes which enable the margins 44 to easily slip away from engagement with the lower face 71 by expanding the supporting

portions

42, 42 as shown by chain lines in FIG. 4(b).

FIG. 5 shows the interior arrangement of the pushbutton switch of the present invention and also several operating states from the initial ordinary state (FIG. 5(a)) to the final switched on state (FIG. 5(e)) in successive order.

Referring to FIG. 5, a reed switch element 52 stands vertically in the center of housing 51 which is provided with a holding means 58 for holding a magnetic member 60 at the upper portion of housing 51. This housing 51 also contains a lower spring 56 in its interior, and on the top of the lower spring 56, a magnet 53 is mounted by wayof magnet support member 59. This magnet 53 is attracted to the above-mentioned mag netic member 60 in the ordinary state (FIG. 5(a) refers) of the push-button switch. A vertically movable pusher 57 contains a first upper spring 54 resting on the top end 66 of magnet support member 59 so that the first spring 54 is capable of applying a resilient force to the magnet 53 and moreover, magnet support member 59 is designed so as to be insertable into pusher 57 corresponding to the pusher being pushed, as shown in e. g. FIG. 5(b). A second upper spring 55 also rests on magnet 53, and the distance between its top end and the lower pushingend face 62 of the above-mentioned pusher 57 is a predetermined distance X, which distance defines the later explained first push-down dis placement of the push-button switch of the present invention.

Also, in the ordinary state, there is a predetermined distance X as shown in FIG. 5(a) between the inner pushing end face 64 of pusher 57 and the top end 66 of magnet support member 59 which distance X is determined by the presence of the first upper spring 54 of which the resilience or the stiffness is generally selected so as to have a value slightly lower than that of the second upper spring 55.

In FIG. 5(a), reference numerals 101 to 104 show the electrical leads of the push-button switch.

The operation and the several effects of the pushbutton switch of the present invention will now be explained with further reference to FIG. 5(a) to FIG. 5(a), and further reference to the diagrams of FIG. 6 and FIG. 7.

In the diagrams of FIGS. 6 and 7, the dotted lines represent the conventional push-button switch, while the full lines represent the switch of the present invention.

When the top of key top member 40 is pushed by the operator, pusher 57 moves downwards under the action of the pushing down force linearly increasing from the initial force P and corresponding only to the resistance offered by the first upper spring 54 and undergoes the first pushed down displacement X (FIG.

(b) and FIG. 6 refers). From this displacement X pusher 57 begins to push the top end of the second upper spring 55 as shown in FIG. 5(b) via its lower pushing end face 62.

As a result, the pushing down force applied to pusher 57 must correspond to the resisting force of the sum of the resilient force exhibited by the first upper spring 54 and the resilient force exhibited by the second upper spring 55, and the pushing down force increases linearly along the line having an increased slope as shown in FIG. 6 according to the increase in downward movement of pusher 57 from the displacement X to the next critical displacement X shown in FIG. 5(0).

When the pusher 57 moves down to this critical displacement X,, the pushing down force applied to pusher 57, which is, the critical pushing down force P as shown in FIG. 6, overcomes the critical resisting force produced by the addition of the magnetic attractive force between magnet 53 and the magnetic member 60 held by support means 58, and the initial resilient force exhibited by the lower spring 56, and as a result, magnet 53 carries out a quick snap action directed downwards against the resilient force exhibited by lower spring 56 (FIG. 5(d) and FIG. 6 refer) and simultaneously, the magnetic field of the magnet 53 makes reed switch element 52 carry out the switching action in the same way as in the conventional push-button switch. As a result of this, the push-button switch of the present invention is switched on as shown in FIG. 5(e).

According to the above-mentioned arrangement and the operations of the push-button switch of the present invention, the operator senses the pushing touch in three steps in such a manner that the first soft touch continues from the beginning to the first pushing down displacement X and then, the second resisting touch appears and lasts up to the critical displacement X and at the critical displacement X,, the final yielding touch is created by the above-mentioned snap action.

However, in the conventional push-button switch, the operator can sense the pushing touch in only two steps as seen from FIG. 6.

Therefore in the present invention the operator feels a kind of psychological security from the commencement of pushing the key top member until the point of disconnecting at the first pushed down displacement distance X and thereafter he is psychologically aware of the process preliminary to the final snap action namely the process taking place from the point X, to the critical displacement point X and finally he is rewarded with a definite and satisfying snap action. Thus, the push-button switch according to the present invention provides a keying touch full of variety and therefore, it can not only softens operator fatigue but also provides an extremely effective snap switch from the human engineering point of view.

Ina preferred embodiment of the present invention the values of the pushing down forces P and P, and the values of displacement distances X, and X are selected as follows from the human engineering point of view.

P, z 25 [gramme], X, 1.25 [millimeter] P z [gramme], X -35 [millimeter] And as a result, the resilience of the first upper spring 54 is selected so as to be lower than that of the second upper spring 55.

Also, apart from the above effect, the push-button switch of the present invention provides the following advantages.

Generally, upon completion of the above-mentioned snap action of the push-button switch, the lower spring 56 serves as a kind of damping member. Therefore, the snap action is simultaneously accompanied by the rebound of magnet 53 so that the magnet 53 reaching to the end portion, is pushed up at once by the lower spring 56. However, according to the present invention, the rebound of magnet 53 is restricted by engagement of magnet support member 59 with pusher 57 at the top end 66 and the inner pushing face 64 as shown in FIG. 5(e). In other words, according to the present invention, means are provided for preventing magnet 53 from rebound. After completion of the snap action, pusher 57 is further pushed down to the final displacement X as shown in FIG. 5(e) so that the amount of rebound of magnet 53 is restricted to a predetermined value X X as can be seen from a comparison between FIG. 5(d) and FIG. 5(e).

Thus, if the value X X, is a predetermined suitably selected value, the reed switch element 52 can be completely prevented from the chattering which conventionally occurs at the contact points of the reed switch element 52, since the magnetic field of magnet 53 acting upon the reed switch element 52 barely changes because of the above-mentioned restriction of the rebound of magnet 53.

Further, even if the push-button switch fails to carry out the snap action at the critical displacement X of pusher ,57 for accidental reasons the push-button switch can of course be switched at the-final displacement X because the magnet is directly pushed down by pusher 57 via magnet support member 59.

Next, referring to FIG. 8, a partial assembly of reed switch element 52 and the above-mentioned housing 51 is shown.

As can be seen from the drawing, electrical leads 101 to 104 are disposed in the same vertical plane P which is perpendicular to the vertical walls 68. This plane P intersects the vertical walls 68 at the center of said walls.

Moreover, housing 51 which is usually made of a moldable compound is nearly symmetrical with respect to this plane P.

As a result the molding process of housing 51 having the above-mentioned electrical leads 101 to 104 disposed in the interior of the housing 51 can be easily carried out by employing a molding die which is symmetrically partible in the direction A as shown in FIG. 8 by the parting plane P.

This fact provides the possibility of a continuous manufacturing process as explained, hereinafter with reference to FIGS. 9(a) to 9(d).

That is to say, at first, four lead materials 101 to 104 having lengths corresponding to several units of the reed switch element and housing assembly undergo press working so as to form terminal points for the respective unit shown in FIG. 9(a), and then, they are positioned in the molding die so as to be molded and fixed into housing 51. After one unit of electrical leads and housing assembly is completed, the same molding process is repeated for the next unit while using the same electrical lead materials, as shown in FIG. 9(b).

When the predetermined number of units of electrical leads and housing assembly are completed, they next undergo a bending and cutting process so as to obtain the required shapes of

electrical leads

102 and 103, as shown in FIG. 9(0).

Then, a reed switch element 52 is assembled into each unit of the electrical leads and housing assembly through a welding process as shown in FIG. 9(d). Finally, each unit of the reed switch and housing assembly is completed by the final cutting process.

As will be understood from the above-mentioned explanation, a continuous manufacturing process can be carried out according to the present invention thus providing the possibility of mass production and therefore, reduction of manufacturing cost.

H6. 10 is a side view of the main body 50 of the push-button switch of the present invention.

Referring to FIG. 10, the main body 50 is mounted to mounting plate 90 by a means 58a which is a preferred example of the holding means 58.

The details of the holding means 58a and mounting plate 90 are shown in FIG. 1 1.

As can be seen from FIG. 11, holding means 58a is provided with one pair of mounting

legs

82, 82 and another pair of mounting

legs

84, 84 at ends of both left and right leg portions of the holding means 58a in a projecting fonn.

Fixing of holding means 58 to housing 51 is carried out by engagement of the mounting

legs

84, 84 and

step portions

78, 78 formed on the sides of housing 51, one side of which is shown in FIG. 10.

The above-mentioned engagement is effected merely by forcibly parting the mounting

legs

82, 82 as shown in FIG. 10.

The same fixing manner is carried out with mounting

legs

82, 82 as shown in FIG. 10, for fixing the main body 50 to the mounting plate of e.g. the control panel of the electronic equipment. That is to say, in the mounting plate 90, a number of square openings 92 and cut off portions 91 are formed at the points where the main body 50 of the push-button switch is inserted and is fixed.

As is apparent from the above-mentioned explanation, the push-button switch of the present invention is provided with great ease of assembly.

Further, the holding means 58a shown in detail in FIG. 11 has also an additional advantage explained, hereinafter, with reference to FIG. 12 and FIG. 13.

Referring to FIG. 12, support plate 7, magnet 3 and reed pieces 8 of the reed switch element which are provided for the conventional push-button switch as shown in FIG. 1, are partially shown, and also, the magnetic flux 4) emitted by magnet 3 is shown.

FIG. 13 shows the holding means 58a, magnet 53 and reed pieces of the reed switch element in the present invention. The magnetic flux emitted by magnet 53 is shown as Q.

As can be seen from a comparison of FIG. 12 and FIG. 13, in the conventional push-button switch, the magnetic flux (15 tends to leak out, while in the present invention, leakage of the magnetic flux 0 is reduced to the minimum possible, since the holding means 58a made of magnetic material provides a closed magnetic circuit as shown in FIG. 13.

As a result, magnetic interference which conventionally takes place between neighboring push-button switches in the case where a number of push-button switches are positioned close to one another, never occurs in the present invention, so that reliable switching operation can be carried out at the reed pieces 105, 106 of the reed switch element, shown in FIG. 13(b).

Openings 86 formed in holding means 58a serve to check the movement of the magnet 53 and of course, the dimensions of the openings 86 are selected so as not to increase the above-mentioned leakage.

Next, a push-button switch with a lamp indication ac cording to the present invention will be explained with reference to FIG. 14 and FIG. 15.

Referring to FIG. 14, a lamp indication unit 200 which is a preferred embodiment of the present invention is adapted to the above-mentioned push-button switch main body 50, and also, key top member 40 just prior to fitting to the main body 50 is shown.

FIG. shows the detailed arrangement of the lamp indication unit 200 of the present invention. As shown in FIG. 15(a) to FIG. 15(c), lamp indication unit 200 is constructed from a wire portion 210 and a pair of indication lamps 211, together with a pair of suitably formed wires 213, and a socket portion 220.

The wire 213 has right-angled and

horizontal portions

212, and 213a and a vertical portion 213b extending from one end of wire 213a as shown in FIG. 15(a), and the pair of wires 213 are mechanically and electrically connected to each other by welding the free ends of respective horizontal wires 212 to the lower ends of the respective verticalwires 2l3b so that the portion 210 having a kind of horizontal square shaped wire unit (not given any reference numeral) with a pair of lamps 21 1, and a pair of vertical wires 213b, is constructed.

Socket portion 220 is made of heat-resisting, transparent, easily colored, elastic and easily moldable materials such as silicone or neoplane gum and socket portion 220 includes a square marginal portion 222 which is'provided with a circular opening 221 in the center, portions 223, for containing a pair of lamps and rib portions 224 to reinforce the lamp containing portions 223. The square marginal portion 222 is provided with a pair of holes 222a in which is inserted the abovementioned pair of vertical wires 21312 as shown in FIG. 15(0) and a pair of elastically deformable slots 222b for engagement of the lamp indication unit 200 with the main body 50 as hereinafter explained.

- As can be seen again from FIG. 14, the main body 50 is provided with a pair of projections 79 having notches 790 (F IG. 8 also refers).

The pair of projections 79 are capable of clicking with the above-mentioned pair of slots 222b of the lamp indication unit 200.

Thus, when the lamp indication unit 200 is adapted tothe main body 50 of the push-button switch, a pair of vertical lead wires 213b extending from the unit 200 are bent and welded to lead

terminals

101, 104 extending from the main body 50 as shown in FIG. 14 so that a pair of lamps 211 is electrically connected to the pushbutton switch of the present invention. Now, the key top member 40 is fitted to the main body 50 by means of claws 41 and projectionsl70 as previously explained and, the push-button switch with lamp indication according to the present invention is completely assembled.

According to the above-mentioned arrangement of the push-button switch with lamp indication, the lamp indication unit 200 is easily changeable.

Therefore, preferably, many kinds of lamp indication units having transparent, milky-white or other several kinds of colored socket portions 220, may be optionally prepared.

Also, many kinds of transparent or colored key top members 40 may be prepared.

Now, 'it will be understood that according to the present invention, the push-button switch with multichoice colored lamp indication, can be obtained and therefore, errors of operation by the operator can be eliminated.

The invention has been described with reference to preferred embodiments, but it will be understood that variations or modifications may be effected within the spirit and the scope of the present invention.

What is claimed is:

l 0 1.- A push-button switch comprising a housing provided with a support means for supporting a magnetic member at an upper portion of said support means;

a magnetic switching element fixedly positioned in said housing;

a lower spring member contained in said housing;

a magnet mounted on said lower spring so as to move up and down in said housing while its upward movement is restrained by said support means and also, while being attracted to said support means in the ordinary'state; a pusher member capable of I moving up and down;

a first upper spring applied to said pusher member at its one end, and mounted on said magnet at its other end; and

a second upper spring also mounted on said magnet at its one end and the other end positioned from said pusher member at a first predetermined pushed down displacement of said pusher member.

2. A push-button switch as claimed in claim 1, further comprising a means capable of engaging with said pusher member upon completion of the snap ac tion of said push-button switch so that the amount of rebound of said magnet is restricted to a preselected value, whereby said magnetic switching element is prevented from chattering.

3. A push-button switch as claimed in claim 2, wherein said means is a support for supporting said magnet.

4. A push-button switch as claimed in claim 1, wherein said first upper spring has a resiliency lower than that of said second upper spring.

5. A push-button switch as claimed in claim 1, wherein said push-button is provided with a key top member changeably mounted on said push-button switch, and wherein said housing is provided with a projection from at least one side wall thereof and having a lower face, and said key top member is provided with a pair of resilient and laterally flexible pawls on at least one side wall thereof, each of said pawls having inwardly protruding claws provided with a top margin which is engageable with said lower face, whereby said pair of claws removably slip into engagement with said lower face due to the lateral flexibility of said pawls.

6. A push-button switch as claimed in claim 5, wherein said push-button switch is provided with engaging projections forrned at the top of said housing, and electrical leads projecting from said projection and capable of being connected to an electrical power source, further comprising a lamp indication unit composed of a socket portion which is provided with lamp containing portions, engaging slots engageable with said engaging projections of said housing and throughholes provided for passing of lead wires therethrough and a wire portion and at least one lamp and a wire connected to said lamp at its one end and to one of said electrical leads of said push-button switch at its other end while extending through said through-holes of said socket portion.

7. A push-button switch as claimed in claim 6, wherein said socket portion is made of a heat-resisting,

transparent easily colored, elastic and easily moldable material.

8. A push-button switch as claimed in claim 1, wherein said housing includes two vertical walls facing each other, and a plurality of electrical leads molded in said housing so as to be disposed in a vertical plane perpendicularly intersecting the center of said both vertical walls, and is formed into a shape symmetrical with respect to said vertical plane so that molding of a plurality of said housing is capable of being continuously carried out.

9. A push-button switch as claimed in claim 1, wherein said support means consists of a magnetic member provided with left and right hand portions extending downward from a portion for supporting said magnetic material in the direction of the movement of said magnet so that closed magnetic circuits are provided for the magnetic flux emitted by said magnet.

10. A push-button switch as claimed in claim 9, wherein each of said left and right hand portions is provided with a first pair of mounting legs at the end thereof which are engageable with stepped portions formed in said housing by forcibly parting said first mounting legs, and a second pair of mounting legs in a form projecting from the middle of said first mounting legs which are to be used for fixing said push-button switch in a required position.

Claims

1. A push-button switch comprising a housing provided with a suppoRt means for supporting a magnetic member at an upper portion of said support means; a magnetic switching element fixedly positioned in said housing; a lower spring member contained in said housing; a magnet mounted on said lower spring so as to move up and down in said housing while its upward movement is restrained by said support means and also, while being attracted to said support means in the ordinary state; a pusher member capable of moving up and down; a first upper spring applied to said pusher member at its one end, and mounted on said magnet at its other end; and a second upper spring also mounted on said magnet at its one end and the other end positioned from said pusher member at a first predetermined pushed down displacement of said pusher member.

2. A push-button switch as claimed in claim 1, further comprising a means capable of engaging with said pusher member upon completion of the snap action of said push-button switch so that the amount of rebound of said magnet is restricted to a preselected value, whereby said magnetic switching element is prevented from chattering.

6. A push-button switch as claimed in claim 5, wherein said push-button switch is provided with engaging projections formed at the top of said housing, and electrical leads projecting from said projection and capable of being connected to an electrical power source, further comprising a lamp indication unit composed of a socket portion which is provided with lamp containing portions, engaging slots engageable with said engaging projections of said housing and through-holes provided for passing of lead wires therethrough and a wire portion and at least one lamp and a wire connected to said lamp at its one end and to one of said electrical leads of said push-button switch at its other end while extending through said through-holes of said socket portion.

7. A push-button switch as claimed in claim 6, wherein said socket portion is made of a heat-resisting, transparent easily colored, elastic and easily moldable material.