CN1296949C

CN1296949C - Limit switch

Info

Publication number: CN1296949C
Application number: CNB2004100633231A
Authority: CN
Inventors: 高桥达司
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2003-12-18
Filing date: 2004-06-29
Publication date: 2007-01-24
Anticipated expiration: 2024-06-29
Also published as: JP2005183131A; KR100629049B1; JP4361361B2; CN1629996A; KR20050062353A

Abstract

The invention provides a limit switch which can be used for long time, of which, contacting property of a movable contact point and a fixed contact point is improved by setting only one contact part. The limit switch comprises a rotation axis rotating by interlocking with an actuator, a movable member arranged on and rotating together with the rotation axis, a movable contact member of which, one end is fixed to the movable member and the other end has a movable contact point, a fixed contact member having a fixed contact point facing the movable contact point at one end and other end is mounted on an external terminal, and a conductive elastic body of which, one end is arranged on the movable member and the other end is arranged on an external terminal different from the above external terminal.

Description

Limit switch

Technical field

The present invention relates in production equipment and industrial machine, be used for determining the limit switch of purposes such as position or object detection.

Background technology

In the limit switch in the past, for example, as a kind of built-in switch, possess: be subjected to the action shaft of plunger pushing, pars intermedia is inserted the 1st contact panel that logical the 1st retaining hole, the both ends that are formed at action shaft have normally closed contact; Pars intermedia is inserted the 2nd contact panel that logical the 2nd retaining hole, the both ends that are formed at action shaft have normal opened contact; Be arranged at the spring that presses between the inner peripheral surface of the 1st and the 2nd retaining hole and the 1st and the 2nd contact panel respectively; And respectively with normally closed contact and normal opened contact from the fixed contact that connects, when detected material contacts with the roller of actuator, directly advance to move to make normally closed contact to leave, make normal opened contact to contact with other fixed contact from fixed contact by making the plunger that is connected with action shaft.(for example with reference to Patent Document 1)

[Patent Document 1] spy opens flat 11-238430 communique

The limit switch that Patent Document 1 is recorded and narrated is constituted as, when detected material contacts with the roller of actuator and is subjected to pushing, be located at the 1st contact panel both ends normally closed contact each leave since fixed contact, the normal opened contact of being located at the 2nd contact panel both ends contacts with other fixed contact separately, thus, built-in switch is opened and closed.Yet because the 1st and the 2nd contact panel both ends are provided with the travelling contact (normal opened contact and normally closed contact) that the action with actuator links, there are 2 places in limit switch contact portion of travelling contact and fixed contact when opening and closing.For this reason, as long as wherein a side contact portion comes in contact badly, no matter how the loop all is in open-circuit condition to the contact condition of the opposing party's contact portion, thereby the problem that limit switch loses normal function takes place in the contact portion that travelling contact and fixed contact constitute.For the limit switch of recording and narrating as Patent Document 1 with 2 place contact portions, 1 contact portion is come in contact bad probability be made as N, then the bring into normal play probability tables of function of the contact portion that is made of travelling contact and fixed contact is shown: Pn=(1-N) * (1-N) with action once

In addition, also can consider travelling contact and fixed contact respectively have one limit switch so that limit switch when opening and closing contact portion only be 1 place, but since the movable contact that possesses travelling contact be with by contact the cause that the actuator that is subjected to external force links with detected material, used the occasion of conductive members such as electric wire from outside terminal to the part of movable contact that connects outer lead, the folding that conductive member then takes place is bent the problem of life-span deterioration.

The content of invention

The present invention carries out for solving above-mentioned problem, and its purpose is, provides by the contact portion with travelling contact and fixed contact and is set as the limit switch that improve contact performance and can realize long-term use at 1 place.

Limit switch of the present invention is characterised in that, has the fixed contact and the travelling contact that contact and leave with the actuator interlock, it is characterized in that this limit switch possesses: the rotation axis that rotates with described actuator interlock; The movable member that is located on this rotation axis, rotates with described rotation axis; The movable contact that end is located on this movable member, the other end has described travelling contact; Have described fixed contact, the other end relative an end and be located at a fixed contact on the outside terminal with described travelling contact; And end is located on the described movable member, the other end is located at the conductive elastomer on another outside terminal.

Because of the present invention has following formation, that is, possess: the rotation axis that rotates with the actuator interlock; Be located at movable member this rotation axis, that rotate with rotation axis; The movable contact that this movable member, the other end have travelling contact is located in end; Have an end be relatively fixed contact, the other end of travelling contact and be located at the fixed contact on the outside terminal; And end is located at the conductive elastomer that movable member, the other end are located at the outside terminal beyond the said external terminal, thereby the contact portion of travelling contact and fixed contact exists only in 1 place, can improve contact performance, and, can use for a long time.

Brief Description Of Drawings

Fig. 1 is the end view of the limit switch of the embodiment of the invention 1.

Longitdinal cross-section diagram when Fig. 2 is in open mode for the body of the limit switch of Fig. 1 of the embodiment of the invention 1.

Dorsal view when Fig. 3 is in open mode for the body of the limit switch of the embodiment of the invention 1.

Fig. 4 is the front view of the conductivity spring of use in the embodiments of the invention 1.

Fig. 5 is the end view of the conductivity spring of use in the embodiments of the invention 1.

The preferred embodiment that carries out an invention

Embodiment 1

Fig. 1 is the end view of the limit switch of embodiments of the invention 1, longitdinal cross-section diagram when Fig. 2 is in open mode for the body of the limit switch of Fig. 1, dorsal view when Fig. 3 is in open mode for the body of the limit switch of embodiments of the invention 1, Fig. 4 is the front view of the conductivity spring of use in the embodiments of the invention 1, and Fig. 5 is the end view of this conductivity spring.

As shown in the figure, the back side has in the body that is the case shape substantially 1 of peristome 1a, rotation axis 2 stride frame in relative two sides, substantially flatly supported, be fixed with actuator 3 on the end of this rotation axis 2.On the top of this actuator 3, promptly on the top position of body 1, abreast the end of axle 3b fixed substantially, be provided with the roller 4 that contacts with detected material (not illustrating) rotationally on this 3b with rotation axis 2.In addition, in the bottom of actuator 3, the below of rotation axis 2 is provided with the 3a of elastomeric support portion.In the bottom of body 1, relatively be provided with the fixation side elastomeric support 1b of portion with the 3a of this elastomeric support portion, between this 1b of elastomeric support portion and 3a, be provided with the elastomer 5 that constitutes by spring coil etc.Actuator 3, because of its underpart is subjected to the application of force to the opposition side of the 1b of elastomeric support portion side of this elastomer 5, being subjected to the rotation axis among Fig. 22 all the time is the center, clockwise power.Thereby, be located at the roller 4 on the top of actuator 3, be subjected to the application of force all the time to the peristome 1a of body 1 side.In addition, the peristome 1a place of body 1 is fixed with and is used for the dustproof lid 12 that waits.

Below, the inside of body 1 is described.

With contact the rotation axis 2 that actuator 3 interlock that produces the external force effect rotates with roller 4 because of detected material on, fixing the bottom of movable member 6.The central portion of this movable member 6, be inserted with the through metalwork 7 of the cylindrical conductivity of the cardinal principle that constitutes by electroconductive component, the through metalwork 7 of this conductivity is striden frame between side of the peristome 1a of movable member 6 side and the another side relative with this side, connect and be provided with.On the opposition side end face of the peristome 1a of the through metalwork 7 of this conductivity, fixing the bottom of movable contact 8 tabular, tool conductivity by bolt 13a, the top of movable contact 8 is provided with travelling contact 8a in the same side with the through metalwork 7 of conductivity.In addition, fixed contact 9 tabular, tool conductivity is the コ font substantially, and the peristome of this コ font is towards the below, and relative side and rotation axis 2 are located at the top of body 1 inside with paralleling.In the relative side of this fixed contact 9, on side of peristome 1a side, position relative with travelling contact 8a on the inner face side end is provided with fixed contact 9a, and the another side then is fixed in its end by bolt 13c and is located on the outside terminal 10a of the side relative with the peristome 1a of body 1.In addition, an end tabular, that be the conductivity spring 11 that is made of conductive elastomer of U font substantially is provided with fixing hole 11a, and the other end is provided with fixing hole 11b.And, this conductivity spring 11 is by this

fixing hole

11a and 11b, rely on bolt 13d that erecting device constitutes and 13b and respectively an end is fixed on the outside terminal 10b with the outside terminal 10a homonymy of body 1 and equidirectional setting, and the other end is fixed on the peristome 1a side end face of the through metalwork 7 of conductivity, the through metalwork 7 of rotation axis 2 and conductivity is located at its U font inboard.In addition, as shown in Figures 3 and 4, because of this conductivity spring 11 is arranged on the position that transverse direction staggers when the peristome 1a side of body 1 is observed, thereby bolt 13b and 13d are arranged at, when the perspective plane of installation direction is observed, on conductivity spring 11 irrelevant positions of disturbing.

The limit switch of above-mentioned formation, because of the effect of the elastomer 5 of being located at body 1 bottom, rotation axis 2 is subjected to the clockwise application of force all the time in Fig. 2, and therefore, travelling contact 8a contacts with fixed contact 9a, and loop integral body is in closure state.At this moment, when roller 4 was pushed by detected material antagonism elastomer 5 ground, actuator 3 was that the center is with rotation axis 2 rotations with rotation axis 2.And then because of these rotation axis 2 rotations, the movable member 6 that rotation axis 2 is fixed in the bottom also rotates with actuator 3 interlocks, and for this reason, strains take place the conductivity spring 11 that movable member 6 and outside terminal 10b are fixed in both ends.Thus, fixed contact 9a and the travelling contact 8a that is located at movable member 6 leave, and the loop all is transformed into open-circuit condition.

The limit switch of embodiments of the invention 1, the contact portion that constitutes because of travelling contact 8a and fixed contact 9a only establishes 1 place, and the limit switch of being located at 2 places with in the past contact portion relatively can improve the contact reliability of contact portion.That is, for the limit switch of

embodiment

1,1 place contact portion is come in contact bad probability be made as N, then be shown: Pn=1-N once to move can the bring into normal play probability tables of function of the contact portion that constitutes by travelling contact 8a and fixed contact 9a

Thereby, the constituent ratio in the past that is present in 2 places with contact portion, the contact reliability of limit switch can improve 1/ (1-N) doubly.In addition, because of being located at outside terminal 10b and movable member 6, when rotation axis 2 rotates, all rolling over conductivity spring 11 in the wrong and have conductivity and elasticity in both ends, thereby with the occasion of using conductive members such as electric wire relatively, can significantly prolong folding and bend the life-span.And then, the through metalwork 7 of conductivity inserts in the movable member 6, be assemblied in the U font inboard of conductivity spring 11 with rotation axis 2, movable member 6 and movable contact 8, travelling contact 8a and fixed contact 9a connect from the time, because of action occurs in the U font inboard of conductivity spring 11, so can realize the miniaturization of limit switch.In addition, outside terminal 10a and 10b are located at equidirectional.In addition, respectively the end that is the conductivity spring 11 of U font substantially is fixed in the bolt 13b and the 13d of outside terminal 10b and the through metalwork 7 of conductivity, be arranged at when the perspective plane of the peristome 1a side of body 1 is observed with conductivity spring 11 irrelevant positions of disturbing.For this reason, when fixed contact 9 is mounted to outside terminal 10a, when conductivity spring 11 is mounted to the through metalwork 7 of outside terminal 10b and conductivity, from peristome 1a side as the body 1 of installation direction, can easily carry out fastening to

bolt

13b, 13c and 13d, the assembleability excellence can realize the cripetura of activity duration.

Claims

1. limit switch has the fixed contact and the travelling contact that contact and leave with the actuator interlock, it is characterized in that this limit switch possesses: the rotation axis that rotates with described actuator interlock; The movable member that is located on this rotation axis, rotates with described rotation axis; The movable contact that end is located on this movable member, the other end has described travelling contact; Have described fixed contact, the other end relative an end and be located at a fixed contact on the outside terminal with described travelling contact; And end is located on the described movable member, the other end is located at the conductive elastomer on another outside terminal.

2. limit switch according to claim 1 is characterized in that movable member is provided with electroconductive component, and this electroconductive component is provided with movable contact and conductive elastomer.

3. limit switch according to claim 2 is characterized in that electroconductive component runs through movable member, is provided with movable contact at an end face, the other end is provided with conductive elastomer.

4. according to each described limit switch in the claim 1 to 3, it is characterized in that, to the erecting device that conductive elastomer is fixed, be located at from the perspective plane of installation direction not with position that described conductive elastomer disturbs mutually on.

5. limit switch according to claim 4 is characterized in that, conductive elastomer is made of the conductivity spring that is the U font, and movable member is located at its U font inboard.

6. limit switch according to claim 5 is characterized in that fixed contact is the コ font, and fixed contact is located at the inner face side of this コ shape.

7. limit switch according to claim 4 is characterized in that, the both ends of conductive elastomer and the other end of fixed contact are mounted from equidirectional.