KR100704105B1 - Limit switch - Google Patents

Abstract

By simply operating the reset lever in one direction, it is possible to maintain a free state and provide a limit switch capable of improving operability.

The limit switch 10 separates the plurality of operating gears, the plurality of connecting pinions, and the pinion from the operating gear side during one-way rotational movement around the support shaft, and resets each operating gear to the home position. The reset arm 33 is provided with a spring for applying a rotational movement force to the reset arm in a direction in which each pinion is brought closer to the operating gear side. The reset arm 40 has a groove extending in the support axis direction in the reset arm and has a cam portion 40b in contact with the groove around the support shaft 40a in a direction orthogonal to the support axis of the reset arm. Rotational movement supports freely. When the reset lever rotates around the support shaft, the cam part slides in the groove in the groove direction, and the cam part receives the reset arm when the reset arm is rotated to the maximum position in the free state, resisting the spring force. The support shaft is located on the line of action of the spring force.

Description

Limit switch {LIMIT SWITCH}             

BRIEF DESCRIPTION OF THE DRAWINGS The longitudinal side view of the deceleration part of the shutter switch provided with the limit switch which concerns on 1st Embodiment of this invention.

2 is a side view of the limit switch.

3 is an elevation view.

4 is a coplanar view.

5 is a plan view of the counter unit.

6 is an exploded perspective view of the operating gear and the connecting pinion;

Fig. 7 is an enlarged view showing the engagement relationship between the engagement groove of the second reset arm and the reset lever in the free state.

8 is a plan view of a limit switch according to a second embodiment.

9 is a front view in which the right half of the limit switch is similarly cut out;

10 is an isometric view, (a) shows a setting state, and (b) shows a free state.

The exploded perspective view which shows the state before assembling the reset lever of a limit switch.

<Description of the symbols for the main parts of the drawings>

10,50: limit switch 21,32,36,64: shaft (support shaft)

22,23,24,25: Operating gear 26,27,28,29: Connecting pinion

33,63: first reset arm 37: second reset arm

38: coil spring (pressure member) 40, 70: reset lever

40a, 70a: support shaft 40b, 70b: cam part

40c, 70c: operation part 41,71: engaging groove

51: Case 52: Box Frame

52a: opening part 52b: bearing part

52c: insertion portion 52d: fitting groove

54 cover 54a: bearing protrusion

54b: engagement protrusion

The present invention relates to a limit switch provided in a switch, such as a shutter or a door, installed at an entrance of a building.

Conventionally, this type of limit switch includes, for example, a plurality of actuating gears rotatably coaxially arranged, as disclosed in Japanese Unexamined Patent Application Publication Nos. 3-47228 and 8-64075. A switch lever is always provided between a plurality of connecting pinions for interlocking operation gears between adjacent operating gears and an outer circumferential surface of the end gear or a cam wheel that rotates integrally with it. The so-called counter type with a micro switch which outputs a stop signal when the tip of the switch comes into contact with the tip of the switch lever is inserted into the recess provided at one place of the outer circumference.

In the case of setting a stop position such as a shutter by adjusting such a limit switch, the shutter or the like must be opened and closed by a push button operation to a desired position. have. For this reason, in the limit switch, a reset arm that swings around a support shaft extending in the arrangement direction of the operating gear and the connecting pinion is provided, and a reset operation member for operating the reset arm is provided. The set operating member is configured to rotate the reset arm in one direction against the pressing force of the spring so as to separate each connecting pinion from the operating gear side and reset each operating gear to the home position by the cam. . As the reset operation member, there are a push button type as disclosed in Japanese Unexamined Patent Application, First Publication No. 3-47228, and a lever type as disclosed in Japanese Patent Application Laid-open No. Hei 8-64075.

By the way, in the conventional reset operation member, when the push button type is in a free state in which the reset operation member is pushed in the axial direction, the reset operation member does not return to its original position by the pressing force of the spring. Since the projections are provided in the projections, and the projections are engaged with the stoppers formed on the frame to maintain the free state, it is necessary to pull the reset operation member strongly when releasing the free state. There is a problem that the operation is not easy.

Therefore, in order to cope with this problem, the projection of the reset operation member is engaged with the stopper on the frame side by pushing and rotating the reset operation member so that the release can be performed only by the rotation of the reset operation member. One is known. However, especially in the case of shutter switchgear, the switchgear is placed in the shutter box attached to the edge of the entrance of the building, so that the reset control member of the limit switch is also high and the operation is performed through the small inspection door under the shutter box. In the present situation, the operation of pushing and rotating the reset operation member is not easy.

On the other hand, in the lever type, when the reset operation member is rotated in one direction around the support shaft to a free state, the reset operation member is swinged on the frame in order to prevent the reset operation member from returning to its original position by the pressing force of the spring. In the provision of the guide hole for guiding the guide hole, an engaging portion cut out in a direction orthogonal to the swinging direction of the reset operation member is formed at the end of the guide hole to engage the reset operation member with the engagement portion. Is being done. However, in this case, it is necessary to move the reset operation member in two directions, and there is a problem that the movement operation is not easy as the limit switch used in the shutter switch as described above.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object thereof is to make the reset arm rotate freely in one direction against the pressing force of the spring by a lever-type reset operation member. Therefore, it is possible to provide a limit switch capable of maintaining a free state by merely moving the reset lever in one direction and improving the operability.

The 1st invention for solving the said subject is a limit switch which consists of several operation gears rotatably coaxially respectively, and multiple connection which connects an operation gear via these adjacent operation gears, respectively. The pinion is pivotably supported around a support shaft extending in the arrangement direction of the plurality of operating gears and the connecting pinion, and the plurality of connecting pinions are separated from the operating gear side when rotating in one direction. It is assumed that a reset arm for resetting each operating gear to its original position and a pressing member for applying a force to rotate the reset arm in a direction of bringing the respective connecting pinions closer to the operating gear side. . The reset arm is provided with a groove extending in the support shaft direction, and the reset lever having the cam portion in contact with the groove is supported so that the rotational movement is free around the support shaft in a direction orthogonal to the support shaft of the reset arm. do. When the reset lever is rotated around the support shaft, the cam unit slides the inside of the groove in the groove direction, and when the reset arm is rotated as far as possible to resist the pressing force of the pressure member, the reset arm is in a free state. The cam portion is provided such that the support shaft is positioned on the action line of the pressing force of the pressing member received through the reset arm.

In this configuration, the reset lever is moved around the support shaft to change the limit switch from the set state (the limit switch is driven to the output shaft of the switchgear) to the free state (the limit switch is not driven to the output shaft of the switchgear). When rotating, the cam portion of the reset lever slides in the groove of the reset arm, presses the reset arm to rotate in response to the pressing force of the pressing member, and the reset arm rotates to the maximum and becomes free. In this free state, the pressing force of the pressing member acting on the cam portion of the reset lever from the reset arm does not receive the rotational force due to this pressing force so that the support shaft of the reset lever is located on the working line thereof. It is kept free. For this reason, only the rotational movement operation in one direction is sufficient for the operation of the reset lever for changing to the free state. Moreover, since the cam portion is in the groove of the reset arm and does not come out therein during the rotational movement operation of the reset lever, the change operation is surely performed.

Both the 2nd invention and 3rd invention provide one form of the said reset lever. That is, the reset lever of the second invention has a configuration in which the operation portion and the cam portion are formed on the same surface. In this configuration, not only the molding of the reset lever is easy but also the rotational movement operation force of the reset lever is easily transmitted to the reset arm side, thereby improving the operability.

The reset lever of the third aspect of the invention has a configuration in which the operation portion and the cam portion are formed on different surfaces via the support shaft. In this structure, since the contact point between the operation part of the reset lever, the cam part, and the reset arm can be set on another plane or position, the layout layout can be appropriately performed.

4th invention provides the preferable form of the limit switch of 3rd invention description. In particular, when the case of the limit switch is formed by attaching a cover to the opening of the box-shaped frame, a bearing portion for supporting the support shaft of the reset lever in a rotatable manner on the frame, and extends linearly from the opening side to the bearing portion. Insertion portions for inserting the support shaft of the reset lever into the bearing portion are formed, and fitting grooves are provided on both side walls of the insertion portion. On the other hand, a bearing projection portion which is inserted into the insertion portion with both edges fitted to the fitting groove, and also acts as the bearing portion to support the support shaft of the reset lever in a rotatable manner, on the cover, and the reset lever The engaging projection is formed so as to engage with the operation portion in the set state and to maintain the set state.

In this configuration, when assembling the limit switch, the support shaft of the reset lever is inserted into the bearing portion of the frame from the insertion portion, and then both edges of the bearing protrusion of the cover are fitted into the fitting grooves of the both side walls with respect to the insertion portion. The reset lever can be easily assembled by inserting the bearing protrusion in a fitted state and attaching the lid to the opening of the frame. In addition, after assembly, the support shaft of the reset lever is rotatably supported in a state of being fitted to the support shaft portion of the frame and the bearing protrusion of the lid, and the entire operation portion of the reset lever is located on the outer surface side of the frame. The rotary motion operation can be performed easily. In addition, when the reset lever is in the set state, since the operation portion is engaged with the engaging projection of the lid and held in the set state, the reset lever does not inadvertently move and the set position does not change.

Embodiment of the Invention

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described according to drawing.

1 shows a deceleration part of a shutter switch with a limit switch according to a first embodiment of the present invention, where 1 is a housing of a switch and 2 is freely rotated through bearings 3 and 3 in the housing 1. It is an output shaft, and this output shaft 2 receives the power from the motor not shown through the gear 4, and rotates.

A timing gear 5 is mounted on the output shaft 2, and a limit gear 11 as an input gear of the limit switch 10 is engaged with the timing gear 5. The limit switch 10 is attached to the lower part of the housing 1, and the lower side of the limit switch 10 is covered by the dustproof cover 6 which is detachably mounted to the housing 1.

The limit switch 10 has a drive shaft 13 freely rotated between the front wall portion 12a and the rear wall portion 12b of the frame 12 as shown in detail in FIGS. 2 to 4. The limit gear 11 is attached to the end part which extends forward rather than the front wall part 12a of the drive shaft 13. Between the front wall portion 12a and the rear wall portion 12b of the frame 12, two counter units 14, 15 are arranged symmetrically with the drive shaft 13 interposed therebetween, and each counter unit 14 15, the rotational force of the drive shaft 13 is transmitted through a series of idler gears 16, 17 and 18, respectively. The two counter units 14 and 15 correspond to the upper limit position and the lower limit position as the stop position of the shutter, respectively, and the configuration thereof is the same. Therefore, only one counter unit 14 will be described in the following description. .

That is, the counter unit 14 has four actuating gears 22 freely supported, such as idler gears 18, on a shaft 21 extending in parallel with the drive shaft 13 as shown in FIG. 23, 24, 25, between the idler gear 18 and the operating gear 22 in the first position, between the operating gear 22 in the first position and the operating gear 23 in the second position, Interposed between the actuating gear 23 in the second position and the actuating gear 24 in the third position and the actuating gear 24 in the third position and the actuating gear 25 in the fourth position, the fourth position. Four connecting pinions 26, 27, 28 and 29, a switch arm 31 slidably supported around the shaft 30 extending in the arrangement direction in the vicinity of the actuator gears 22 to 25, Operation of the first and second reset arms 33 and the switch arm 31 supported slidably around the shaft 32 extending in the arrangement direction in the vicinity of the pinions 26 to 29. And a micro switch 34 arranged at the bottom of the arm (31a).

On one side of each of the operation gears 22 to 25 (deviated from the idler gear 18), as shown in detail in FIG. 6, the gears 22a, 23a, 24a, and 25a are formed around the entire circumference, respectively. On one side of each of the operation gears 22 to 25, a heart-shaped reset cam (not shown) is formed around the through hole 35 of the shaft 21, respectively. In addition, two gears 22b, 23b, and 24b are formed on the other side of the operating gears 22 to 24 in the first to third positions (opposite to the idler gear 18), respectively. In the other part of the operation gear 25 of a position, the recessed part 25c is formed in one part of the outer peripheral surface. In addition, the pinion 26 has two gears formed at both the idler gear 18 and the gear 22a of the operating gear 22 in the first position, and the pinion 27 has two gears formed at the operating gear 22 in the first position. On both sides 22b and gears 23a of the operating gear 23 in the second position, the pinion 28 has two gears 23b formed in the second operating gear 23 and the third position. On both sides of the gear 24a of the actuating gear 24, the pinion 29 has two gears 24b formed in the actuating gear 24 in the third position and the gears of the actuating gear 25 in the most end position ( 25a) Engaged to both sides, the connecting operation is performed in which the upper operating gear rotates by one tenth each time the lower operating gear rotates once.

The micro switch 34 has a switch button 34b set to be projected from within the case 34a, and a plate disposed across the upper side of the switch button 34b, and one end of which is fixed to the case 34a. It has a spring 34c. The actuating arm part 31a of the switch arm 31 is in contact with the leaf spring 34c and, apart from the actuating arm part 31a of the switch arm 31, the actuating gear 25 at the most end position. It has a contact projection part 31b which always contacts the outer periphery surface of). In the set state, the micro switch 34 normally presses the leaf spring 34c by the actuating arm portion 31a of the switch arm 31, and the switching button 34b is pressed into the case 34a. And the contact projection portion 31b is inserted into the recessed portion 25c of the operation gear 25 at the end position, the spring of the leaf spring 34c causes the switch arm 31 to be turned on. Simultaneously pushing up the operation arm part 31a, the switching button 34b protrudes in the case 34a, and it is turned OFF.

On the other hand, each of the pinions 26 to 29 is freely rotatable on the shaft 36, and the shaft 36 is supported by the second reset arm 37 and is the first. It is provided to engage with the reset arm 33. Then, when the first reset arm 33 is rotated in one direction around the shaft 32, the second reset arm 37 also rotates around the shaft (not shown), and each pinion 26 While the 29 to 29 fall off from the operating gears 22 to 25, four pressing pieces (not shown) formed on the second reset arm 37 are used to reset the cams of each of the operating gears 22 to 25. The actuators 22 to 25 are reset to their original positions in contact with the. At this time, the switch arm 31 receives the pressing force from the first reset arm 33 and rotates about the shaft 30 so that the micro switch 34 is turned on.

On the shaft 32 of the first reset arm 33, the first reset arm 33 is rotated in a direction in which the respective pinions 26 to 29 are close to the operating gears 22 to 25 side. A coil spring 38 is provided as a pressing member for applying a force to make a force, and a reset lever 40 for rotating the first reset arm 33 in response to a pressing force of the coil spring 38 is provided. The rotary motion is freely supported on the bearing portion 12c of the frame 12. The reset lever 40 includes a support shaft 40a supported by the bearing portion 12c of the frame 12 and a cam portion 40b extending upward from the support shaft 40a toward the reset arm 33. And an operating portion 40c extending downward from the frame 12 through the slit hole l2d of the frame 12 in the support shaft 40a, wherein the cam portion 40b and the operating portion 40c are formed on the same surface. The support shaft 40a protrudes to both sides from this surface.

The reset lever 40 is arranged such that the support shaft 40a is orthogonal to the shaft 32, which is the support shaft of the first reset arm 33, in plan view, and at the periphery of the support shaft 40a. The cam portion 40b comes in contact with the first reset arm 33 during the rotational movement within a predetermined range (between the set state shown by the solid line in FIG. 2 and the free state shown by the imaginary line). As shown in detail in FIG. 7, the first reset arm 33 includes an engaging groove 41 extending in the axial direction of the shaft 32 in contact with the cam portion 40b of the reset lever 40. ) Is formed. Then, when the reset lever 40 rotates around the support shaft 40a, the cam portion 40b slides the fitting groove 41 in the groove direction, and at the same time, the pressing force of the coil spring 38 is applied. The cam portion 40b extends vertically upward from the support shaft 40a when the first reset arm 33 is rotated to the maximum in a free state, and the cam portion 40b is the first reset arm (1). The support shaft 40a is positioned on the line of action of the pressing force of the coil spring 38 received through 33).

Next, the operation of the first embodiment, in particular, the state switching by the reset lever 40 will be described. Now, in one counter unit 14 of the limit switch 10, each of the connecting pins 26 to 29 is close to and engaged with the operating gears 22 to 25, respectively. At this time, the rotational force input from the output shaft 2 of the switchgear to the drive shaft 13 via the timing gear 5 and the limit gear 11 is operated via the idler gears 16, 17 and 18. 25), the coupling operation is performed between the actuating gears 22-25 and the pinions 26-29. In addition, as shown by the solid line in FIG. 2, the reset lever 40 has the operation part 40c lowered vertically downward from the support shaft 40a, and the cam part 40b is inclined from the support shaft 40a and upwards. It is in an inclined state. This state is the setting state.

Then, when the reset lever 40 is rotated around the support shaft 40a from this setting state, a force for pushing up from the cam portion 40b of the reset lever 40 to the first reset arm 33 acts. The reset arm 33 is rotated as far as possible around the shaft 32 in response to the pressing force of the coil spring 38 so that the respective connecting pins 26 to 29 are spaced apart from the operating gears 22 to 25. . At this time, the rotational force input to the drive shaft 13 is not transmitted to the operation gears 22 to 25, and is in a free state.

In this free state, as shown in the phantom line in the reset lever 40, the cam portion 40b extends vertically upward from the support shaft 40a, and the cam portion 40b is the first reset arm. Since the support shaft 40a is located on the action line of the pressing force of the coil spring 38 received through the 33, the reset lever 40 does not receive the rotational force around the support shaft 40a due to this pressing force. It is kept free. Therefore, the operation of the reset lever 40 is sufficient to operate only the rotational movement in one direction, and since only one finger can be operated, it can be easily set even in a narrow place and the operability can be improved. However, during the rotational movement operation of the reset lever 40, the cam portion 40b slides in the engaging groove 41 of the first reset arm 33 in the direction of the groove and is pulled out of the engaging groove 41. Since it does not come out, it is possible to reliably operate the rotational movement of the reset lever 40 and to change the state.

In addition, since the operation part 40c and the cam part 40b are formed on the same surface, the said reset lever 40 can facilitate shaping | molding of this reset lever 40, and the reset lever 40 It is easy to transmit the rotational motion operation force at the operation part 40c of the control part to the 1st reset arm 33 side, and can improve the operability further.

8 to 10 show a limit switch 50 according to the second embodiment of the present invention. The case 51 of the limit switch 50 has a box-shaped frame 52 having an opening 52a, and covers the opening 52a in the frame 52 by fixing four screws 53. The cover 54 is attached, and the drive shaft 55 penetrating the inside of the case 51 in the front-rear direction is freely installed, and the limit gear 56 is formed at one end of the drive shaft 55. Is equipped.

In addition, in the case 51, although not shown in detail in the drawing, as in the case of the limit switch 10 according to the first embodiment, two counter units 58 and 59 are viewed in plan and the drive shaft 55 is viewed. They are arranged symmetrically with). The configuration of the counter units 58 and 59 is the same as that of the counter units 14 and 15 in the first embodiment, but on the upper side of the operating arm portion 61a of the switch arm, that is, on the cover 54 side. The micro switch 62 is arrange | positioned. Moreover, the 1st reset arm 63 is normally set by the coil spring (not shown) attached to the shaft 64, and is in the setting state shown by the solid line in FIG. 9, The reset arm 63 Is rotated from the setting state around the shaft 64 to the state shown by an imaginary line in FIG. 9, each connecting pinion is spaced apart from the operation gear (similarly not shown) and becomes a free state.

Then, a reset lever 70 for rotating the first reset arm 63 against the pressing force of the coil spring is rotatably supported by the bearing 52b of the box-shaped frame 52. . As shown in FIG. 11, this reset lever 70 is the support shaft 70a supported by the bearing part 52b of the box-shaped frame 52, and the box-shaped frame 52 of this support shaft 70a. It consists of the cam part 70b provided in the inner end part, and the operation part 70c provided in the end part of the outer side of the box-shaped frame 52 of the support shaft 70a, and the cam part 70b and the operation part 70c are supported. It is formed on the other surface via the shaft 70a, and protrudes in the direction substantially orthogonal to each other as seen from the axial direction of the support shaft 70a.

The first reset arm 63 is formed with an engaging groove 71 extending in the axial direction of the shaft 64, and the cam portion 70b of the reset lever 70 is provided in the engaging groove 71. Is to be contacted. Then, when the reset lever 70 rotates around the support shaft 70a, the cam portion 70b slides in the engagement groove 71 in the groove direction and resists the pressing force of the coil spring. When the reset arm 63 is rotated to the maximum state in the free state, as shown in Fig. 10B, the cam portion 70b extends vertically downward from the support shaft 70a, and the cam portion 70b is The support shaft 70a is positioned on the line of action of the pressing force of the coil spring received through the first reset arm 63.

On the other hand, at the side wall portion of the box-shaped frame 52, a bearing portion 52b for supporting the support shaft 70a of the reset lever 70 in a rotatable manner is formed, and at the same time, the bearing portion 52b is provided. Insertion portions 52c for inserting the support shafts 70a of the reset lever 70 into the grooves are formed to extend linearly from the opening portion 52a side to the bearing portion 52b. Both sides of the insertion portions 52c are formed. A set of fitting grooves 52d and 52d are provided in the wall, respectively. The lid 53 is provided with a bearing protrusion 54a which protrudes toward the box-shaped frame 52 and whose both edges are fitted into the fitting grooves 52d and 52d. Then, the support shaft 70a of the reset lever 70 is inserted into the bearing portion 52b of the box-shaped frame 52 through the insertion portion 52c, and then the bearing protrusion 54 of the lid 54 is moved. Both edges of the bearing protrusion 54 are inserted into the insertion portion 52c in a state of being fitted into the fitting grooves 52d and 52d of the insertion portion 52c, respectively, and the lid 54 is inserted into the box-shaped frame 52. When the screw (53) is fixed, the support shaft (70a) of the reset lever (70) is fitted by the bearing portion (52b) of the box-shaped frame (52) and the front end of the bearing protrusion (54a) of the cover (54). Rotation is supported freely.

Further, the side wall portion of the box-shaped frame 52 is in contact with the operation portion 70c when the operation portion 70c of the reset lever 70 is brought into a free state (state shown in FIG. 10 (b)). The stopper portion 52e for restricting further rotational movement is formed by the above, and at the same time the cover portion 54 is set to the setting state in which the operation portion 70c of the reset lever 70 is set in the vertical direction. And engaging projections 54b for engaging with each other and holding in a set state.

And also in the said 2nd Embodiment, when it is set as the free state which knocks down the operation part 70c of the reset lever 70 sideways, like the case of 1st Embodiment, the cam part 70b of the reset lever 70 is carried out. Since the support shaft 70a is located on the line of action of the pressing force of the coil spring received through the first reset arm 63, the reset lever 70 causes the rotation of the rotational force around the support shaft 70a due to this pressing force. It does not receive and is kept free. Therefore, only the rotational movement operation in one direction is sufficient for the operation of the reset lever 70, so that the operability can be improved. In addition, during the rotational movement operation of the reset lever 70, the cam portion 70b slides the engagement groove 71 of the first reset arm 63 in the groove direction, and thereby engages in the engagement groove 71. Since it does not come out of, the rotational lever operation of the reset lever 70 and the state switching can be surely performed.

In addition, since the operation part 70c and the cam part 70b of the reset lever 70 are formed on the other surface via the support shaft 70a, the two parts 70b and 70c are provided as in the present embodiment. By arranging the inner side and the outer side of the box-shaped frame 52 separately, an arrangement layout in which the operation unit 70c is rotated along the side wall of the box-shaped frame 52 can be adopted, and the operability can be further improved. . In addition, when the reset lever 270 is set, the operation part 70c engages with the engaging protrusion 54b of the lid 54 and is kept in the set state. Thus, the reset lever 70 vibrates the switch. The setting position is not changed by inadvertently moving with the back.

At the time of assembling the limit switch 50, the support shaft 70a of the reset lever 70 is inserted into the bearing portion 52b of the box-shaped frame 52 through the insertion portion 52c. With respect to the portion 52c, the bearing projection portion 54 is inserted into the fitting grooves 52d and 52d of the both side walls in such a state that both edges of the bearing projection portion 54 of the lid 54 are fitted, respectively. By attaching the 54 to the opening 52a of the box-shaped frame 52 and fixing the screw 53, the reset lever 70 can be easily assembled and attached, and workability can be improved. .

In addition, this invention is not limited to the said 1st and 2nd embodiment, Comprising: Various other forms are included. For example, in the first embodiment, the connecting pinions 26 to 29 are spaced apart from the operating gears 22 to 25, and the reset pins are used to reset the respective operating gears 22 to 25 to their original positions. As an arm, the 2nd reset arm 37 which rockably supports the connecting pinions 26-29, and the 1st for transmitting the operating force of the reset lever 40 to this 2nd reset arm 37 are shown. The case where the reset arm 33 is provided will be described and the second embodiment has such a configuration. However, the present invention provides the operation force of the reset lever with respect to the reset arm that supports the connecting pinion so as to swing. The same applies to direct delivery.

Moreover, in the said 1st Embodiment, although the limit switch provided in the shutter switchgear was demonstrated, it cannot be overemphasized that this invention is similarly applicable to the limit switch provided in switchgear, such as a door other than a shutter.

As described above, according to the limit switch of the present invention, it is sufficient to operate the reset lever in only one direction even when the reset arm is made into a free state by rotating the reset arm against the pressing force of the pressing member. In addition, since the operability can be improved, and the change operation can be reliably performed, it has an excellent effect on practicality, and is particularly effective when used in a shutter switch.

In particular, in the second invention, not only the molding of the reset lever can be easily formed, but also the rotational movement operation force of the reset lever can be easily transmitted to the reset arm side, so that the operability can be further improved.

Further, in the third aspect of the present invention, since the contact point with the reset arm of the reset lever and the operation portion can be set at different positions, the arrangement layout can be appropriately performed.

In addition, according to the fourth aspect of the invention, not only can the assembly and attaching of the reset lever be easily performed, but also the entire operation part of the reset lever is located on the outer surface side of the frame, so that the rotational movement can be easily performed, thereby improving the operability. Further, it is possible to achieve further, and also has an effect that the reset lever can be prevented from inadvertently moving and changing from the set position.

Claims (4)

A plurality of actuating gears each rotatably installed on the coaxial, a plurality of connecting pinions for connecting the actuating gears interposed between these adjacent actuating gears, and an arrangement direction of the plurality of actuating gears and the connecting pinions; A reset arm which is swivelably supported around the support shaft extending in the direction of the support shaft and which separates the plurality of connecting pinions from the operating gear side while revolving in one direction, and resets each of the operating gears to the home position; In the limit switch provided with a pressing member for applying a force to rotate the reset arm in the direction in which the respective connecting pinion close to the operating gear side, The reset arm is provided with a groove extending in the support axis direction, while a reset lever having a cam portion that abuts in the groove is freely supported with a rotational movement around the support axis in a direction orthogonal to the support axis of the reset arm, The reset lever has a cam portion that slides in the groove in the groove direction when the rotary lever is rotated around the support shaft, and at the same time freely rotates the reset arm in the free state in response to the pressing force of the pressing member. A limit switch, characterized in that the support shaft is installed on the action line of the pressing force of the pressing member received through the reset arm. The limit switch according to claim 1, wherein the reset lever has an operation portion and a cam portion formed on the same surface. The limit switch according to claim 1, wherein the reset lever is formed on a different surface with the operation portion and the cam portion interposed therebetween. The case of the limit switch is formed by attaching a cover to an opening of a box-shaped frame, the frame including a bearing portion for supporting the support shaft of the reset lever in a rotatable manner, and from the opening side to the bearing portion. An extension portion is formed to extend in a straight line to insert the support shaft of the reset lever into the bearing portion, and fitting grooves are formed on both side walls of the insert portion, while the side edges are fitted on the fitting groove on the cover. A bearing protrusion which is inserted into the insert portion in one state and works with the bearing portion to rotatably support the support shaft of the reset lever, and engages with the operation portion when the reset lever is in the set state to maintain the set state. Limit switch with engaging projection.

Images