JP4615668B2 - Motor valve micro switch mounting structure - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a motor valve that opens and closes a flow path by rotating a valve body by a motor. More particularly, the present invention relates to a microswitch mounting structure for mounting a microswitch for detecting the opening / closing position of a valve body.
[0002]
[Prior art]
Conventionally, there is a motor valve in which a valve body is rotated by a motor to open and close a flow path. In this motor valve, in order to accurately open and close the flow path, it is necessary to accurately stop the rotation of the valve body at the open position and the closed position. Therefore, a micro switch is attached to the motor valve in order to detect the opening / closing position of the valve body and accurately stop the motor.
[0003]
An example of this type of microswitch mounting structure is shown in FIGS. This mounting structure includes a pair of upper and lower micro switches 50 and 51 and a rotating cam 52 provided adjacent to the side surfaces of both switches 50 and 51. The upper microswitch 50 is for detecting the open position (or closed position) of the valve body, and the lower microswitch 51 is for detecting the closed position (or open position) of the valve body. . Each of the microswitches 50 and 51 includes a box-shaped switch body 50a and 51a, movable contacts 50b and 51b provided on the side surfaces thereof, pin holes 50c and 51c that vertically penetrate the switch bodies 50a and 51a, and an attachment hole 50d. , 51d. Both microswitches 50 and 51 are rotatably supported by a casing 54 of the motor valve around a fixed pin 53 incorporated in both pin holes 50c and 51c.
The rotating cam 52 is rotated by the output shaft 55 of the motor, and includes two upper and lower recesses 52a and 52b on the outer periphery thereof. The upper recess 52a corresponds to the open position (or closed position) of the valve body, and receives the movable contact 50b of the upper microswitch 50. The lower recess 52b corresponds to the closed position (or open position) of the valve body, and receives the movable contact 51b of the lower microswitch 51. Although the motor is not shown in FIG. 6, the motor is fixed on a plurality of support posts 56 shown in the figure, which are provided perpendicular to the casing 54.
[0004]
In order to urge and press the side surfaces of the microswitches 50 and 51 against the outer peripheral surface of the rotating cam 52, an arcuate fixed arm 57 capable of elastic deformation is provided. The proximal end portion of the fixed arm 57 is fixed to the casing 54, and the distal end portion is attached to the attachment holes 50d and 51d of the microswitches 50 and 51. The fixing arm 57 is made of resin in order to eliminate the need for mounting accuracy and to eliminate adjustment during mounting. By pressing the micro switches 50 and 51 against the outer peripheral surface of the rotating cam 52 by the fixed arm 57, the operation of the switches 50 and 51 is ensured.
[0005]
Accordingly, when the output shaft 55 of the motor is rotated by a predetermined amount in order to open and close the valve body, the rotary cam 52 is rotated integrally with the output shaft 55. At this time, the positions of the recesses 52a and 52b change, and the corresponding movable contacts 50b and 51b are received in the recesses 52a and 52b. As a result, each micro switch 50, 51 is turned on, and it is detected that the valve body has reached the open position or the closed position. In response to this, the motor is stopped and the rotation of the valve body is accurately stopped. Can do.
[0006]
[Problems to be solved by the invention]
However, in the conventional mounting structure, since the resin-made fixing arm 57 is used, there is a problem that the elastic force of the fixing arm 57 is lowered. That is, the resin-made fixing arm 57 is easily affected by heat from the surroundings, and changes with time are relatively fast. For this reason, the force which presses each micro switch 50 and 51 against the rotating cam 52 becomes unstable, and there is a possibility that the operation of the switches 50 and 51 becomes unstable.
[0007]
In order to deal with the above problem, it is conceivable to replace the urging means of the microswitches 50 and 51. However, even if the urging means is replaced, if the microswitches 50 and 51 and the casing 54 are required to be processed or additional parts are required, preparation will be troublesome, and the minimum It is desirable to keep it down to change.
[0008]
The present invention has been made in view of the above circumstances, and an object thereof is to make it possible to stably press the microswitch against the rotating cam for a long period of time, and to make the configuration thereof relatively simple. It is an object of the present invention to provide a microswitch mounting structure for a motor valve that is made possible.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, the invention according to claim 1 is a micro-machine provided for detecting an opening / closing position of a valve body in a motor valve that opens and closes a flow path by rotating the valve body by a motor. A switch mounting structure, in which a motor is supported by a support provided in a casing, a first microswitch and a second microswitch including a movable contact and a mounting hole provided in a switch body, and a first microswitch And the second microswitch are vertically stacked and supported on the casing so as to be swingable via a mounting pin, and are rotated by a motor and in the swinging direction of the first microswitch or the second microswitch. A rotating cam including an outer peripheral surface capable of contacting the movable contact, the outer peripheral surface including a recess for receiving the movable contact; and a first micro A metal first torsion spring for pressing the switch against the rotating cam, a metal second torsion spring for pressing the second microswitch against the rotating cam, a first torsion spring and a second torsion spring, Including a central loop and a pair of spring ends extending linearly in different directions from the central loop, including one end of the spring end formed in a loop shape and the other end bent at a right angle; The center loop is attached to the mounting pin, and one loop-shaped spring end is engaged with the support column, and the other spring end is engaged with the mounting hole of the first micro switch or the second micro switch. by being the first micro switch, the second micro switch, a first torsion spring, and with the second torsion spring is mounted is sandwiched by a casing and a motor, the side surface of the first micro switch,及 By the side surface of the second micro switch is pressed against the outer peripheral surface of the rotating cam, the first micro switch itself, and a second micro switch itself and the first micro switch mounting pin to the shaft by rotation of the rotary cam second It is intended that the micro switch swings independently.
[0010]
According to the configuration of the present invention, since a metal torsion spring is used, the torsion spring is less susceptible to influences from the surroundings, such as thermal influences and changes with time, compared to a resin urging member. Distortion is less likely to occur. In addition, a torsion spring is provided, the center loop of which is attached to the mounting pin of the micro switch, and each spring end is engaged with the mounting hole of the motor post or the switch body, so that the micro switch is attached to the casing. The side surface of the microswitch is pressed against the outer peripheral surface of the rotating cam.
[0011]
In order to achieve the above object, the invention described in claim 2 includes a pair of recesses provided corresponding to the movable contacts of the first microswitch or the second microswitch in the invention described in claim 1. No it to the spirit of the.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment embodying a microswitch mounting structure of a motor valve of the present invention will be described in detail with reference to the drawings.
[0014]
FIG. 1 shows a sectional view of a motor valve 11 of this embodiment. The motor valve 11 is configured such that a valve body 13 is rotated by a motor 12 to open and close a flow path 14. The motor valve 11 includes a motor 12, an electric circuit board 15 for the motor 12, an upper casing 18 that houses a pair of micro switches 16, 17 for detecting the opening / closing position of the valve body 13, the valve body 13 and the flow A lower casing 19 including a passage 14 and the like, and an intermediate casing 20 that connects the upper casing 18 and the lower casing 19 to each other are provided.
[0015]
In the upper casing 18, the motor 12 is supported on a plurality of support columns 21. The electric circuit board 15 is supported by the upper and lower clamps 22. In the space provided below the motor 12, the output shaft 12 a of the motor 12 and both microswitches 16 and 17 are arranged. Along with the microswitches 16 and 17, a rotating cam 23 is fixed on the output shaft 12a.
[0016]
The intermediate casing 20 accommodates a connecting shaft 24 connected to the output shaft 12a. The valve body 13 provided in the lower casing 19 has a substantially spherical shape, and includes a valve hole 13a penetrating the center. The valve shaft 25 protruding from the upper portion of the valve body 13 is connected to the output shaft 12 a via the connecting shaft 24. One end of the lower casing 19 is an inlet 14a of the flow path 14, and the other end is an outlet 14b.
[0017]
Therefore, in the state shown in FIG. 1, the valve hole 13 a of the valve body 13 is disposed at a closed position that is perpendicular to the flow path 14, and thus the flow path 14 is blocked. From this state, by operating the motor 12 and rotating the output shaft 12a by a predetermined amount, the valve body 13 is rotated via the connecting shaft 24 and the valve shaft 25, and the valve hole 13a communicates with the flow path 14. Located in the open position.
[0018]
Next, the mounting structure of the microswitches 16 and 17 will be described. FIG. 2 is a sectional view taken along line 2-2 in FIG. FIG. 3 is a front view showing the mounting structure of the microswitches 16 and 17.
[0019]
The pair of microswitches 16 and 17 are arranged one above the other. The upper microswitch 16 is for detecting the open position (or closed position) of the valve body 13, and the lower microswitch 17 is for detecting the closed position (or open position) of the valve body 13. It is. Each of the microswitches 16 and 17 includes a box-shaped switch main body 16a and 17a, movable contacts 16b and 17b provided on the side surfaces thereof, pin holes 16c and 17c and mounting holes 16d penetrating the main bodies 16a and 17a up and down. , 17d. Both microswitches 16 and 17 can swing in the horizontal direction (left and right direction in FIG. 1) around the pin 26 by incorporating pin holes 16c and 17c into the mounting pin 26 provided in the upper casing 18. Supported by
[0020]
The rotating cam 23 rotated by the output shaft 12a of the motor 12 is provided on the outer peripheral surface 23a that can contact the movable contacts 16b and 17b in the swinging direction of the micro switches 16 and 17, and the outer peripheral surface 23a. It includes a pair of recesses 23b and 23c having a V shape for receiving the movable contacts 16b and 17b. Both dents 23b and 23c are divided into an upper side and a lower side of the outer peripheral surface 23a, and are arranged at a predetermined angle. The upper recess 23 b corresponds to the open position (or closed position) of the valve body 13 and receives the movable contact 16 b of the upper micro switch 16. The lower recess 23c corresponds to the closed position (or open position) of the valve body 13, and receives the movable contact 17b of the lower microswitch 17.
[0021]
The microswitches 16 and 17 are provided with metal torsion springs 27 and 28 for pressing the switches 16 and 17 against the rotary cam 23, respectively. 4 shows a plan view of the torsion springs 27 and 28, and FIG. 5 shows a front view of the torsion springs 27 and 28, respectively. The torsion spring 27 includes a central loop 27a and a first and second pair of spring ends 27b and 27c extending linearly from the loop 27a in different directions. The first spring end portion 27b is provided with a base end loop 27d having a diameter larger than that of the central loop 27a. The end of the second spring end portion 27c forms a tip end portion 27e bent at a right angle. Both torsion springs 27 and 28 have the same shape except that the tip 28e is bent to the opposite side of the tip 27e of the torsion spring 27 .
[0022]
As shown in FIG. 3, the torsion springs 27 and 28 are attached to the upper surface of the upper microswitch 16 and the lower surface of the lower microswitch 17, respectively. In this arrangement state, the center loop 27a is attached to the mounting pin 26 as shown in FIG. The proximal loop 27d is fitted and engaged with one of the columns 21. The tip 27e is inserted into and engaged with the mounting holes 16d and 17d. Thus, the micro switches 16 and 17 are attached to the upper casing 18 and the side surfaces of the micro switches 16 and 17 are pressed against the outer peripheral surface 23a of the rotating cam 23 in the swing direction. In the mounting structure of this embodiment, the mounting pin 26, the mounting holes 16d, 17d, and the support column 21 are the same as the mounting pin 53, the mounting holes 50d, 51d, and the support column 56 of the conventional mounting structure described above. The torsion springs 27 and 28 are attached using the above.
[0023]
As described above, according to the microswitch mounting structure of this embodiment, the metal torsion springs 27 and 28 are used to press the microswitches 16 and 17 against the outer peripheral surface 23 a of the rotating cam 23. Accordingly, the torsion springs 27 and 28 are less susceptible to the influence of heat from the surroundings than the resin fixed arm 57 in the conventional example, change with time is less likely to cause permanent distortion, and a decrease in elastic force is suppressed. . Therefore, the micro switches 27 and 28 can be stably pressed against the rotating cam 23 for a long period of time, and the operations of the micro switches 16 and 17 can be stabilized for a long period of time.
[0024]
According to this mounting structure, only the torsion springs 27 and 28 are newly provided for the upper casing 18 and the micro switches 16 and 17 having the same configuration as the conventional one. Then, the central loops 27 a and 28 a of the torsion springs 27 and 28 are engaged with each other by using the mounting pins 26 provided on the upper casing 18, and the base end loops 27 d and 28 d are engaged with the support 21 for the motor 12. The microswitches 16 and 17 are engaged with each other by using one of them, and the tip portions 27e and 28e are engaged with the mounting holes 16d and 17d of the microswitches 16 and 17, respectively. 18 and the side surface of each micro switch 16.17 is pressed against the outer peripheral surface 23a of the rotating cam 23 in the swinging direction. For this reason, in addition to providing the torsion springs 27 and 28, special processing and addition of separate parts can be omitted, and the configuration for the mounting structure can be made relatively simple.
[0025]
Moreover, according to this attachment structure, a pair of upper and lower microswitches 16 and 17 can be attached integrally. In addition, as shown in FIG. 2, the torsion springs 27 and 28 are arranged along the upper and lower surfaces of the microswitches 16 and 17, and there is no overhanging portion, so that it is more compact than the conventional mounting structure. It can be a mounting structure. The upper microswitch 16 can detect that the valve body 13 has reached the open position (or the closed position), and the lower microswitch 17 can detect the valve body 13 in the closed position (or the open position). Can be detected.
[0026]
In addition, this invention is not limited to the said embodiment, In the range which does not deviate from the meaning of invention, it can also implement as follows.
[0027]
(1) In the above embodiment, the first spring end portions 27b, 28b of the torsion springs 27, 28 are provided with the proximal end loops 27d, 28d to be engaged with the support column 21, but the proximal end loops 27d, 28d may be omitted and only the spring end portions 27b and 28b may be engaged with the column 21.
[0028]
(2) In the above embodiment, the present invention is embodied in an attachment structure for attaching a pair of microswitches 16 and 17; however, the attachment structure for attaching only one microswitch or three or more microswitches is used. It can also be embodied.
[0029]
【The invention's effect】
According to the configuration of the first aspect of the invention, the microswitch can be stably pressed against the rotating cam for a long period of time, and the operation of the microswitch can be stabilized for a long period of time. The effect that can be made relatively simple is exhibited.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a motor valve according to one embodiment.
2 is a cross-sectional view taken along line 2-2 of FIG.
FIG. 3 is also a front view showing a connection relationship between the microswitch and the rotary cam.
FIG. 4 is a plan view showing a torsion spring in the same manner.
FIG. 5 is a front view showing a torsion spring in the same manner.
FIG. 6 is a cross-sectional view showing a conventional mounting structure.
FIG. 7 is a front view showing a conventional mounting structure.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 11 Motor valve 12 Motor 13 Valve body 14 Flow path 16 Micro switch 16a Switch main body 16b Movable contact 16d Mounting hole 17 Micro switch 17a Switch main body 17b Movable contact 17d Mounting hole 18 Upper casing 21 Post 23 Rotary cam 23a Outer peripheral surface 23b Recess 23c Recess 26 mounting pin 27 torsion spring 27a center loop 27b first spring end 27c second spring end 28 torsion spring 28a center loop 28b first spring end 28c second spring end

Claims (2)

A microswitch mounting structure provided for detecting the open / close position of the valve body in a motor valve that rotates the valve body by a motor to open and close the flow path,
The motor is supported by a support provided in a casing;
A pair of first microswitch and second microswitch including a movable contact and a mounting hole provided in the switch body;
The first micro switch and the second micro switch are vertically stacked and supported on the casing so as to be swingable via a mounting pin;
An outer peripheral surface that is rotated by the motor and is capable of contacting the movable contact in the swinging direction of the first microswitch or the second microswitch, and the outer peripheral surface has a recess for receiving the movable contact. Including a rotating cam, and
A metal first torsion spring for pressing the first microswitch against the rotating cam; and a metal second torsion spring for pressing the second microswitch against the rotating cam;
The first torsion spring and the second torsion spring include a central loop and a pair of spring ends extending linearly in different directions from the central loop, and one end of the spring end is formed in a loop shape, Including a tip part whose other end is bent at a right angle;
The center loop is mounted on the mounting pin, the one loop-shaped spring end is engaged with the support column, and the other spring end is the first microswitch or the second microswitch. The first micro switch , the second micro switch, the first torsion spring , and the second torsion spring are sandwiched and attached by the casing and the motor, The side surfaces of the first microswitch and the second microswitch are pressed against the outer peripheral surface of the rotating cam, so that the first microswitch itself and the second microswitch itself rotate the rotating cam. The first micro switch and the second micro switch swing independently about the mounting pin by movement. Microswitch mounting structure of the motor valve and.   2. The motor switch microswitch mounting according to claim 1, wherein the recess of the rotating cam includes a pair of recesses provided corresponding to movable contacts of the first microswitch or the second microswitch. Construction.

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