JPH0112036Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electric valve operating device that controls the opening and closing of a switch mechanism by moving a movable body.

Generally, a control valve driven and controlled by an electric motor is equipped with a valve operating device that converts the rotational movement of the output shaft by the electric motor into linear movement, and moves the valve shaft of the valve body linearly in the axial direction. . in this case,
A switch mechanism for controlling an electric motor is required to have a simple structure, be easy to install and remove, and be able to reliably stop the electric motor at a predetermined position. In addition to the switch mechanism, this type of valve operating device is also required to include a position detection mechanism for detecting the position of the valve stem during operation.

The present invention was developed in view of the above-mentioned points, and the switch mechanism is composed of a slide cam that is guided and held in the direction of movement of a movable body, and a pair of switches that are controlled to open and close by this slide cam. ,
Due to the extremely simple structure in which the slide cam is connected to the rotation prevention mechanism provided on the movable body by a connecting rod, the switch mechanism can be easily installed and removed, and the electric motor can be reliably stopped at a predetermined position. The present invention provides an electrically operated valve operating device.

Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.

Fig. 1 is a vertical cross-sectional view showing one embodiment of the electric valve operating device according to the present invention, Fig. 2 is a plan view of the device with the cover removed, Fig. 3 is an enlarged cross-sectional view taken along the line of Fig. 1; FIG. 4 is a sectional view taken along the line shown in FIG. 2.

In these figures, the electric valve operating device, which is designated as a whole by reference numeral 1, includes an electric motor 2, a reduction gear mechanism 3, a linear motion mechanism 6 including a lead screw 4 and a movable body 5,
Consists of main parts such as bearings 7 and 8 and mechanical parts,
It is disposed above the control valve 9 via a yoke 10. Note that the control valve 9 has an upper lid 1 that constitutes the valve body.
When the valve shaft 12 with one end protruding above the valve shaft 1 is moved up and down by the electric valve operating device 1, a valve plug (not shown) provided at the inner end of the valve shaft 12 is operated. Seat ring (not shown)
Since this constitutes a conventionally well-known two-way valve or three-way valve for controlling the opening and closing of the hole, detailed configuration and explanation thereof will be omitted.

In this embodiment, the electric motor 2 is an AC motor or a DC motor having a rotating output shaft, and is fixed to the frame 13 with a mounting screw 14. The frame 13 is formed into a substantially U-shape, so that a pair of mounting portions 13A, 13 facing each other are provided.
B, and a base 13c that connects these pair of mounting parts 13A and 13B, one of the mounting parts 13A
The electric motor 2 is disposed on the outer surface of the other mounting portion 13B, and the bearing 7 is disposed coaxially with the electric motor 2 on the outer surface of the other mounting portion 13B.
The tip of 5 is rotatably supported.

As appropriately shown in FIG. 3, the bearing 7 has a hollow cylindrical bearing mounting body 17 that is fitted and fixed from the outside into a through hole 16 provided in a mounting portion 13B. The tip end of the output shaft 15 is inserted through a radial bearing 19, rotatably supported by a thrust bearing 18, and movement in the axial direction is prevented by a screw 26, which will be described later. A thrust bearing 1 is provided on the outer peripheral surface of the tip of the output shaft 15.
8 is fitted with a retaining ring 20 for receiving thrust in the right direction in the figure, and a semicircular recess is formed in the distal end surface of the shaft 15, and a ball 21 is fitted into this recess and fixed by caulking. ing. A male thread 22 is formed on the outer peripheral surface protruding from the through hole 16 of the bearing mounting body 17, and a female thread is formed on the inner peripheral surface of the male thread 22 to form a cap 2.
3 is screwed on, and is prevented from loosening by a set screw 24. This cap 23 is nut 25
It has a screw 26 screwed in through the screw 2.
The ball 21 is supported at the tip end surface of the output shaft 15, allowing fine adjustment of the output shaft 15 in the axial direction and supporting leftward thrust. The bearing mounting body 17
Further, a highly viscous lubricant 27 such as grease is sealed inside, and thereby the thrust bearing 18, the radial bearing 19 and the balls 21
This prevents wear, rust, etc. of the output shaft 15, and reduces the friction torque of the output shaft 15. On the other hand, the base of the output shaft 15 is connected to one mounting portion 1 of the frame 13.
The output shaft 15 is inserted and held in a bearing hole 28 formed at 3A to position the output shaft 15.

The reduction gear mechanism 3 includes a worm 30 provided at the intermediate portion of the output shaft 15 and located between the pair of attachment portions 13A and 13B, and a worm wheel 31 that meshes with the worm 30 at all times. In this case, for convenience of explanation, FIGS. 1 and 2 show an example in which the worm 30 is formed integrally with the output shaft 15, but in actual equipment, the worm 30 and the output shaft 15 are integrated as shown in FIG. It is common sense and desirable to form them as separate members and connect them using a suitable shaft joint 28. The worm wheel 31 is fitted onto the upper end of the lead screw 4, which is disposed in a direction perpendicular to the output shaft 15 (vertical direction) with a predetermined distance between the shafts, and is secured by a nut 32. Fixed. The lead screw 4 is disposed above and coaxially with the valve shaft 12, and is supported by a bearing 8 so as to be rotatable and prevented from moving in the axial direction.

As shown in FIG. 1, the bearing 8 has a pair of upper and lower bearing fittings 33, 34 through which the lead screw 4 commonly passes.
A pair of thrust bearings 35 and 36 are housed inside to pivotally support the lead screw 4. In this case, the pair of thrust bearings 35 and 36 are disposed above and below a collar 37 that is integrally provided on the outer periphery of the lead screw 4. The pair of bearing mounting bodies 33, 34
can be separated by screwing the male threaded portion 33a provided on the outer circumferential surface of the lower end of the upper bearing mounting body 33 into the female threaded portion 34a provided on the inner circumferential surface of the upper end of the lower bearing mounting body 34. They are combined and fixed at a predetermined position with respect to the frame 13 and the cylinder 40 that constitute the device fixing part by means of a presser flange 38, which will be described later. And the bearing mounting body 33,
Through holes 41 formed on the upper and lower surfaces of 34,
Radial bearings 43 and 44, which rotatably support the lead screw 4, are press-fitted and fixed to 42, respectively.

The base 13C of the frame 13 is connected to the cylindrical body 40.
It is firmly fixed to the upper end surface of the bearing body by a plurality of mounting screws 45, and a fitting hole 46 into which the lower bearing mounting body 34 is fitted is provided in the center. Further, the lower bearing mounting body 34 is also fitted into the inner hole 47 of the cylinder body 40, and the lower surface of the fitting body is abutted and latched to a stepped portion 48 provided on the upper end opening side of the inner hole 47. This prevents it from being inserted into the cylindrical body 40 any further. On the other hand, the presser flange 38 is fitted onto the outer periphery of the upper bearing mounting body 33. This presser flange 38 has a plurality of screw mounting holes formed near the outer periphery, each of which has a mounting screw 50 inserted therein.
is inserted into the upper end surface of the cylindrical body 40 through the attachment hole 51 provided in the base 13C of the frame 13.
is pressed downward, thereby pressing the lower bearing mounting body 34 against the stepped portion 48. Therefore, the pair of bearing mounting bodies 33 and 34 are coaxially and firmly fixed to the cylinder body 40 in a screwed-together state. Note that when the upper bearing mounting body 33 is screwed into the lower bearing mounting body 34, the pair of thrust bearings 35 and 36 come into contact with the collar 37, so that play in the axial direction of the lead screw 4 can be eliminated. . Additionally, the frame 13 has a mounting portion 13A.
has the bearing hole 28 for positioning the electric motor 2 at a predetermined location, and by positioning and fixing itself on the cylindrical body 40, the worm 30 and the worm wheel 31, in other words, the output shaft 15 and the axis of the lead screw 4. The distance can be set with high precision.

The cylindrical body 40 has a lower end fitted into a fitting hole 54 provided at the center of the frame 53, and a nut 56 is screwed onto the downwardly protruding end of the frame 53, so that the cylindrical body 40 can be attached to the frame 53. 53 and is fixed upright. In this case, the cylinder 40 is connected to the pin 55
is positioned and prevented from rotating. A movable body 5 is disposed in the lower part of the interior of the cylinder 40 and is moved in the vertical direction as the lead screw 4 rotates.
is slidably inserted.

The movable body 5 has an outer cylinder 57 and an inner cylinder 58 disposed coaxially within the outer cylinder 57, and the outer cylinder 57 is slidably inserted into the inner hole 47 of the cylinder body 40. . The inner cylinder 58 is a guide block 6 which will be described later.
0 constitutes an oil tank 61, and this inner cylinder 5
The lower end of a lead nut support 63 is slidably inserted into the upper end opening of the lead nut support 63 via an O-ring 62. The lead nut support 63 is formed in a hollow shape, and its upper end is connected to the inner hole 64 of the outer cylinder 57.
It is fixed by welding, etc. Further, a lead nut 65 made of a material with excellent wear resistance and low friction is press-fitted into the inside of the lead nut support 63 and fixed by caulking. This caulking fixation is performed by bending the upper end opening of the lead nut support 63 toward the center and pressing it against the upper surface of the lead nut 65. The lead screw 4 is inserted into the screw hole 65A of the lead nut 65.
A male threaded portion 66 provided on the outer peripheral surface of the lower end portion is screwed.

The guide block 60 that constitutes the oil tank 61 together with the inner cylinder 58 is fitted into the lower end opening of the inner cylinder 58 and fixed by welding.
The lower end opening of 8 is sealed. And inner cylinder 5
8 contains lubricant 67 such as lubricating oil and grease.
This prevents the external threaded portion 66 of the lead screw 4 and the lead nut 65 from being worn out due to lack of oil film or lack of oil, thereby ensuring smooth rotation of the lead screw 4.

By the way, as mentioned above, when an AC motor or a general DC motor is used as the motor 2, if the motor 2 is forced to stop while the current is on, problems such as overheating often occur in the motor 2, and the output torque characteristics of the motor 2 is not constant with only the input signal, and has load followability, so excessive stress is applied to various parts of the electric valve operating device 1 and the control valve 9 side, often causing problems. Therefore, in order to prevent such a malfunction, a buffer spring 68 constituting a buffer mechanism is interposed between the outer cylinder 57 and the inner cylinder 58, and when the control valve 9 is fully closed, the buffer spring 68 is compressed more than when it is assembled. The electric motor 2 is stopped when the compressor is further compressed by a predetermined amount. Therefore, the buffer spring 68 has a pair of spring receivers 69 that are fitted to the outer peripheries of the inner cylinder 58 and the guide block 60 so as to be able to move up and down.
The bullet is loaded between A and 69B, and the upper spring receiver 69A
A retaining ring 70 fitted to the outer peripheral surface of the upper end of the inner cylinder 58 prevents the inner cylinder 58 from coming off. On the other hand, the guide block 6 allows the lower spring receiver 69B to come out downward.
This is prevented by the large diameter portion 60A provided at the lower end of the 0. The stopper 71 is fitted onto the outer peripheral surface of the guide block 60 so as to be prevented from rotating, and its outer peripheral edge is fitted into the lower end opening of the outer cylinder 57 and fixed by caulking or the like. This rotation is prevented by using a pair of axially symmetrical protrusions 72 and notches 73 provided on the inner and outer circumferential surfaces of the stopper 71, respectively, as shown in FIG. A pair of engagement grooves 74 provided on the surface
(See Figure 1). Further, the stopper 71 is fixed by caulking by bending the lower end opening of the outer cylinder 57 toward the center and pressing the stopper 71 from below.
3, a stepped portion 7 provided on the inner circumferential surface of the lower end opening.
Just press it to 5. At this time, a portion of the lower end opening of the outer cylinder 57 bites into the notch 73, thereby firmly preventing the stopper 71 from rotating. In addition,
The buffer spring 68 is assembled by inserting the spring 68 between the pair of spring receivers 69A and 69B into an integrated body consisting of the inner cylinder 58 and the guide block 60 through the lower end opening of the outer cylinder 57, in which the spring 68 is elastically mounted between the pair of spring receivers 69A and 69B. This is done by fitting the stopper 71 into the lower end opening of the outer cylinder 57 and fixing it by caulking, and then the lead nut support 63 is installed inside the outer cylinder 57.
Note that a stepped portion 88 for locking the spring receiver 69A is provided on the inner circumferential surface of the outer cylinder 57.

A screw hole 76 is formed in the center of the lower surface of the guide block 60, and a connecting bolt 77 is screwed into the screw hole 76 via a nut 78. A bolt 80 is disposed in the head 77A of the connecting bolt 77 so as to pass through the bolt 77 in the diametrical direction, and is fixed by a pair of nuts 81 and 82. The tip of the bolt 80 is formed sharply to form a pointer, and the pair of left and right connecting fittings 83, 84 are connected to the bolt 7 together with the pair of nuts 81, 82.
It is fixed at 7. The connecting fittings 83 and 84 have insertion holes (not shown) provided at their straight upper ends that are in close contact with both sides of the head of the connecting bolt 77, respectively, and the bolt 80 is inserted into these insertion holes. There is. On the other hand, the lower end portions of the connecting fittings 83 and 84 are bent into a substantially hook shape, with their tips facing each other, and the upper end portion of the valve stem button 85 is held between these lower end portions. The valve stem button 85 is connected to the valve stem 1.
2, and its upper surface abuts the lower surface of the head 77A of the connecting bolt 77. In addition, the upper end of a locking fitting 86 formed in a substantially L-shape is fixed to the bolt 80 by a nut 87, and the lower end of the locking fitting 86 is fixed to the bolt 80.
It is formed in a U-shape when viewed from above in FIG. 1, and prevents the valve shaft 12 from rotating by engaging with the outer periphery of the hexagonal portion of the valve shaft button 85.

As a rotation prevention mechanism for the movable body 5, a pair of left and right rollers 90, 91 is used as shown in FIG. These pair of rollers 90 and 91 are rotatably supported via spacers 94 at intermediate portions of roller support pins 92 and 93, respectively, which are attached to the outer peripheral surface of the upper end of the outer cylinder 57 from inside the outer cylinder 57. has been done. The pair of roller support pins 9
2 and 93 project outward from elongated holes 95 and 96 formed in the axial direction on the circumferential surface of the cylindrical body 40, respectively, and a nut 9 is inserted into the projecting end through a washer 97.
8 are each screwed on. The pair of rollers 90 and 91 are located within the respective elongated holes 95 and 96 to prevent the movable body 5 from rotating. Therefore, when the lead screw 4 rotates, the movable body 5 moves only in the vertical direction, and at this time the pair of rollers 9
0 and 91 rotate in contact with the hole wall surfaces of the respective elongated holes 95 and 96, thereby reducing the frictional resistance with the cylindrical body 40.

An electric motor 2 is mounted on the base 13C of the frame 13 in correspondence with the pair of roller support pins 92 and 93.
A switch mechanism 100 and a position detection mechanism 101 are provided. The switch mechanism 10
0 is a slide cam 10 that is slidably guided and held by a pair of vertically arranged rails 102a and 102b, as shown in FIGS. 2 and 4.
3, and a pair of micro switches 104 and 105 disposed on both sides of the slide cam 103. The slide cam 103 is connected to the connecting rod 10
It is fixed to the upper end of 6 with screws so that its position can be adjusted.
The lower end of this connecting rod 106 extends below the frame 13 from a hole 107 provided in the base 13C of the frame 13, and extends from the roller support pin 9
Connecting rod 108 rotatably supported at the tip of No. 2
It is connected by screws. Therefore, when the movable body 5 moves up and down, the connecting rod 106 moves up and down together with the roller support pin 92, so that the slide cam 103 moves up and down along the pair of rails 102a and 102b. Further, on both sides of the slide cam 103, inclined cam surfaces 112 and 11 are provided.
3 are integrally protruded. As shown in FIG. 4, the cam surfaces 112 and 113 are formed so that their inclination directions are opposite to each other. The attached rollers 117 are pressed against each other.

In this case, when the slide cam 103 rises with the rise of the movable body 5, the cam surface 112 gradually presses the roller 117 of the micro switch 104, elastically deforming the elastic piece 116, and the slide cam 103
When the switch 104 reaches the uppermost position, the switch 104 is closed. The electric motor 2 is stopped by the signal at this time. On the other hand, when the slide cam 103 descends as the movable body 5 descends, the cam surface 113 gradually presses the roller 117 of the micro switch 105 and elastically deforms the elastic piece 116 of the switch 105. When the lower position is reached, the micro switch 105 is closed, thereby stopping the electric motor 2.

The position detection mechanism 101 is for detecting the opening degree of the control valve 9 as the movable body 5 moves up and down, and sending the detection signal to an appropriate display or control means.
Similar to the switch mechanism 100, a pair of rails 1
It has a slider 121 that is slidably held in the vertical direction by 20a and 120b, and a wiper 122 of a potentiometer shown in FIG. 2 is disposed on one side of the slider 121, and a resistor 123
is in elastic contact with. The slider 121
is fixed to the upper end of a connecting rod 124, and the lower end of this connecting rod 124 is threadedly connected to a connecting rod 125 that extends below the frame 13 and is rotatably supported by the roller support pin 93. There is. Therefore, when the movable body 5 moves up and down, the connecting rod 124 moves up and down together, so that the slider 121 moves up and down along the pair of rails 120a and 120b. As a result, the wiper 122 and the slider 12
1 and changes the contact position with the resistor 123, thereby changing the resistance value of the position detection mechanism 101.

The switch mechanism 100 and the position detection mechanism 101 are respectively housed in cases 127 and 128 fixed to the upper surface of the base 13C of the frame 13, and the pair of micro switches 104 and 105 are positioned on the inner wall of the case 127. Fixed.

As shown in FIG. 1, the frame 53 on which the cylindrical body 40 is erected and fixed is placed on the upper surface of the yoke 10 and is firmly fixed by a plurality of bolts 130. A lower end opening of a cover 131 that covers the electric valve operating device 1 is fixed by a set screw 132 . The yoke 10
is formed into a substantially U-shape, and its lower end is fitted into the upper part of the upper lid 11 and fixed by two setscrews 133. Further, on the inner surface of the yoke 10, a scale plate 134 is provided on the set screw 1 in correspondence with the bolt 80.
35 and a long hole 136 so that the height can be adjusted. On the surface of this scale plate 134 are numbers "0" and "100" indicating when the control valve 9 is fully closed and fully open.
is displayed. Next, the operation of the electric valve operating device 1 having such a configuration will be explained. Note that the explanation assumes that a three-way valve is operated.

When the electric motor 2 stops and the lower seat ring of the control valve 9 is fully closed, the movable body 5 stops at the lowest position, and the pointer, that is, the tip of the bolt 80 points to the number "0" on the scale plate 134. are doing. At this time, a slight gap _G1 is created between the lower spring receiver 69B and the stopper ₇₁ , as shown in FIG. , a larger thrust is applied to the valve shaft 12. In this case, the upper spring receiver 69A is press-locked to a step 88 provided inside the outer cylinder 57 by the force of the buffer spring 68, and a gap G ₂ equal to the gap G ₁ is created between the upper spring receiver 69A and the retaining ring 70. arise.

In this state, the electric motor 2 is energized,
When the output shaft 15 is rotated in the forward direction, this rotation is reduced by a predetermined reduction ratio by the worm 30 and the worm wheel 31, and is transmitted to the lead screw 4. When the lead screw 4 rotates, the movable body 5 equipped with the lead nut 65 screwed into it gradually rises because it is prevented from rotating by a pair of rollers 90 and 91, and the valve connected to the connecting bolt 77 moves upward. Pull up the shaft 12. That is, the rotational motion of the output shaft 15 is decelerated by the reduction gear mechanism 3, and converted into linear motion by the linear motion mechanism 6 made up of the lead screw 4 and the movable body 5.
is transmitted to move the valve shaft 12. The relationship between the amount of rotation and the amount of movement of the valve stem 12 at this time shows extremely good linear characteristics.

When the movable body 5 rises, the male threaded part 66 of the lead screw 4 falls relatively, so it enters the oil tank 61 as shown in FIG. It will be done. When the movable body 5 further rises and reaches the uppermost position, the upper seat ring of the control valve 9 is fully closed and the pointer 80 moves toward the scale plate 1.
34 number "100" and switch mechanism 10
0 microswitch 104 (see FIG. 4) is closed by cam surface 113, stopping electric motor 2. In this case, since the movable body 5 stops at a position where the upper seat ring of the control valve 9 is still raised by a predetermined amount after the upper seat ring is fully closed, a stopper 71 fixed to the lower end opening of the outer cylinder 57 is moved as shown in FIG. Push up the lower spring receiver 69B as shown. On the other hand, since the retaining ring 70 is fitted onto the outer periphery of the cylinder 58 which is movable relative to the outer cylinder 57, the outer cylinder 57 moves upward and a slight gap is created between the stepped portion 88 and the spring receiver 69A. occurs. As in the case when the lower seat ring is fully closed, the buffer spring 68 is compressed by a predetermined amount more than the compression amount at the time of installation. Therefore, even when the upper seat ring is fully closed, the spring load can be applied upwardly to the valve stem 12 by the buffer spring 68.

When the lower seat ring is fully open, the electric motor 2
When the output shaft 15 is rotated in the opposite direction to the above, the movable body 5 descends, and when it reaches the lowest position, the micro switch 105 is closed.
Stop the electric motor 2. At this time, the lower seat ring of the control valve 9 is fully closed.

In the above configuration, a case has been described in which a pair of micro switches 104 and 105 are used as the switches, but the present invention is not limited to this, and it goes without saying that various conventionally known switches may be used.

As explained above, the electric valve operating device according to the present invention includes a slide cam that guides and holds a switch mechanism that controls an electric motor so as to be slidable in the direction of movement of a movable body, and a pair of slide cams that are controlled to open and close by this cam. The slide cam is connected to the rotation prevention mechanism of the movable body by a connecting rod, and the cam is operated integrally with the movable body, so that the movable body is not in a predetermined position. The electric motor can be reliably stopped when the In addition, the structure is simple and installation and removal are easy, and the anti-rotation mechanism can be effectively used as a slide cam drive unit, so it has great practical effects.

[Brief explanation of the drawing]

Fig. 1 is a vertical cross-sectional view showing one embodiment of the electric valve operating device according to the present invention, Fig. 2 is a plan view of the device with the cover removed, Fig. 3 is an enlarged cross-sectional view taken along the line of Fig. 1; 4 is a sectional view taken along the line of FIG. 2, FIG. 5 is a plan view of the stopper, and FIGS. 6 and 7 are diagrams for explaining compression of the buffer spring. 1... Electric valve operating device, 2... Electric motor, 3...
Reduction gear mechanism, 4... Lead screw, 5... Movable body, 6... Linear motion mechanism, 7, 8... Bearing, 9
... Control valve, 12 ... Valve shaft, 15 ... Output shaft, 3
0...Worm, 31...Worm wheel, 4
0...Cylinder body, 65...Lead nut, 65A...
Screw hole, 66... Male thread part, 90, 91... Roller, 92, 93... Roller support pin, 95, 96
... Long hole, 100 ... Switch mechanism, 103 ...
Slide cam, 104, 105...Micro switch, 106...Connecting rod, 112, 113...Cam surface.

Claims (1)

[Scope of utility model registration request] An electric motor, a worm provided on the output shaft of the electric motor, and a worm wheel that constantly meshes with the worm are rotatably supported, the worm wheel is fixed to one end, and a thread is formed on the outer peripheral surface of the other end. a movable body that is connected and fixed to the valve shaft of the valve body and simultaneously screwed into the male threaded portion of the lead screw; a cylinder into which the movable body is slidably fitted; A roller that is rotatably disposed on the outer periphery of the body via a roller support pin and that prevents rotation of the movable body by being inserted into a long hole provided in the cylindrical body, and a roller that operates in conjunction with the movable body. The switch mechanism includes a slide cam that is guided and held so as to be movable in the moving direction of the movable body, and the slide cam is fixed at one end and the other end is connected to the roller support pin. An electric valve operating device comprising: a connecting rod; and a pair of switches that control the electric motor by opening and closing as the slide cam moves.