JPS6126884Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a ratio setting device for a pneumatic meter.

Conventional pneumatic ratio setters use a large number of pivots and links, resulting in a complicated mechanism and a disadvantage in that they require a large number of man-hours for manufacturing and adjustment.

In order to eliminate this drawback, the present invention provides an input pressure receiving element and a feedback pressure receiving element at both ends of the lever, so that deformation of these pressure receiving elements causes the lever to rotate and displace in opposite directions. The mechanism is simplified by taking advantage of the fact that the displacement of each pressure receiving element is inversely proportional to the distance from the point of application.

Embodiments of the present invention will be explained below with reference to the drawings. FIG. 1 is an explanatory configuration diagram showing an embodiment of the present invention, and FIG. 2 is an enlarged detailed side view of the nozzle flap section seen from the - cross section in FIG. 1.

〓〓〓
In Fig. 1, 1 is the first lever, 2 is an input bellows that acts on the first lever 1 at point A at the tip of the first lever 1, and the input bellows acts on the first lever 1 at point A at the tip of the first lever 1 with a force proportional to the received air pressure. push. 3 is a first spring facing the input bellows 2;
It is attached so that point A of the input bellows 2 is pressed from the opposite side.

4 is a feedback bellows that acts on the first lever 1 at point B at the distal end of the first lever 1, and is attached from the opposite side to the input bellows 2 so as to act at point B of the first lever 1, and responds to the received air pressure. Push point B of the first lever 1 from the opposite side with a proportional force. Reference numeral 5 denotes a second spring facing the feedback bellows 4, which is attached so as to push the point B of the first lever 1 from the side opposite to the feedback bellows 4.

As shown in FIG. 2, 6 is a second lever that contacts the first lever 1 at point C through a pin 7 at its tip, and 8 is a nozzle provided at the end of the second lever 6 with a slight gap. The nozzle 8 and the distal end of the second lever 6 form a nozzle flap. 10 is a leaf spring whose end is fixed to the nozzle 8, and whose tip is connected to the center part D of the second lever 6.
The pin 7 is brought into contact with a point C of the first lever 1 by the force of a leaf spring 10.

2, 11 is a proportional setting dial attached to the end of the nozzle 8, and 12 is a dial 1.
When you turn dial 11 with the pointer fixed at 1,
The leaf spring 10 and the second lever 6 rotate together with the nozzle 8, and the point C where the pin 7 contacts the first lever 1 is at point A.
Move towards point or point B.

13 is an air pressure source connected to the nozzle 8; 14 is an amplifier connected to the nozzle 8 and the air pressure source 13; the amplifier 14 receives the air pressure from the air pressure source 13 and the back pressure of the nozzle 8, and outputs an output pressure Po. At the same time, the configuration is such that an output pressure Po is applied to the feedback bellows 4.

Next, the operation will be explained. In such a configuration, when input pressure Pi is applied to the input bellows 2, the input bellows 2 expands and moves the point A of the first lever 1 to the first position.
Pushing in the X direction against the force of the spring 3, the first lever 1 moves to B where the feedback bellows 4 acts.
It rotates around a point and is displaced. As a result, since the pin 7 is held down by the biasing force of the leaf spring 10 against the C point of the first lever 1, the pin 7 of the second lever 6 follows the displacement of the C point of the first lever 1. 1, in the direction opposite to Z. As a result, the second lever 6 rotates around point D, and the end of the second lever 6 facing the nozzle 8 moves in the Z direction in FIG. , the gap between the end of the second lever 6 facing the nozzle 8 is reduced and the spinal pressure of the nozzle 8 is increased.

As spinal pressure increases, the output pressure from the intensifier 14
Po increases, and the increased output pressure Po is applied to the feedback bellows 4. As a result, the feedback bellows 4 extends and moves the point B of the first lever 1 to the second position.
It is pushed in the Y direction against the force of the spring 5, and the first lever 1 rotates and is displaced around point A, where the input bellows 2 acts, and point C of the first lever 1 touches the pin of the second lever 6. 7 is displaced upward in FIG. 1, that is, in the Z direction. Due to this displacement of the pin 7, the second lever 6 rotates counterclockwise around point D, and the second lever 6
The end of the second lever 6 facing the nozzle 8 moves in the direction opposite to Z in FIG. .

At this time, the displacement of point A in the X direction is x, and the displacement of point B is Y
If the displacement in the direction is y, the length between points A and C is a, and the length between points B and C is b, then the relationship between displacements x and y is y/x=b /a becomes.

Now, to simplify the problem, input bellows 2
Assuming that the effective area of the feedback bellows 4 is equal and the spring constants of the first spring 3 and the second spring 5 are equal, Po/Pi=y/x=b/a, Po=(b/a)Pi =KPi (however, K=b/a)
becomes.

Therefore, the amplifier 14 always outputs an output pressure Po at a constant ratio (K) to the input pressure Pi.

Then, when the dial 11 is turned, the second lever 6
rotates together with the nozzle 8, the position of point C changes, and the ratio K=b/a changes.

〓〓〓〓
Therefore, if the support plate 9 is marked with a scale so that the ratio can be read with the pointer 12, the ratio can be set by turning the dial 11 and the output pressure Po can be maintained at that ratio to the input pressure Pi. Can be done.

FIG. 3 is an explanatory configuration diagram showing a modified embodiment, and the same elements as those of the embodiment shown in FIG. 1 are given the same reference numerals and detailed explanations are omitted.

In this example, the input bellows 2 and the feedback bellows 4 are mounted on the same side of the first lever 1, and the This is an example in which the distal end is attached to the tip of the third lever via a bendable leaf spring.

In FIG. 3, reference numeral 15 denotes a third lever rotatably supported by a fulcrum 16, and the end point B of the first lever 1 is connected to the tip of the third lever 15 via a bendable leaf spring 17. There is. 18 is the fulcrum 19
The fourth lever is rotatable around the pin 2 at the tip.
The input bellows 2 and the first spring 3 are provided so that the input bellows 2 contacts the first lever 1 at a point A at the tip of the first lever 1, and the input bellows 2 acts on the distal end. When the input pressure i is applied to the input bellows 2, the input bellows 2 expands against the force of the first spring 3, and the fourth lever 18 moves to the fulcrum 19.
Rotates around. As a result, the pin 20 pushes the point A of the first lever 1 in the X direction, the first lever 1 rotates around the point B where the leaf spring 18 is located, and the input pressure Pi
Displaced in proportion to.

Also, the feedback bellows 4 is connected to the third lever 1.
5, the feedback bellows 4
and a second spring 5 are attached. When the output pressure Po from the amplifier 14 is applied to the feedback bellows 4, the feedback bellows 4 expands against the force of the second spring 5.
The third lever 15 rotates around the fulcrum 16. As a result, the first lever 1 is rotationally displaced about point A so that point B, where the leaf spring 17 is located, is displaced in the Y direction in proportion to the output pressure Po.

Therefore, the ratio can be set by turning the dial as in the previous embodiment.

In this invention, the first lever is provided on which the input bellows and the feedback bellows act, and the point where the second lever contacts the first lever is changed to change the ratio of input pressure to output pressure. The structure is extremely simple and the effect is great.

In the above embodiments, a bellows is used as the pressure receiving element, but the pressure receiving element is not limited to the bellows, and a diaphragm or the like may be used. Moreover, it goes without saying that the ratio can be set not only by the dial but also by other means.

[Brief explanation of the drawing]

Fig. 1 is an explanatory configuration diagram showing an embodiment of the present invention, Fig. 2 is an enlarged detailed side view of the nozzle/flap part seen from the cross section in Fig. 1, and Fig. 3 is an explanatory configuration showing a modified embodiment. It is a diagram. 1: First lever, 2: Input bellows (input pressure receiving element), 4: Feedback bellows (feedback pressure receiving element), 6: Second lever, 8: Nozzle, 14: Amplifier, Pi: Input pressure, Po: Output Pressure. 〓〓〓〓

Claims (1)

[Scope of utility model registration request] a first lever rotatably disposed around a rotation point; a first lever attached directly or via a lever to a tip of the first lever; an input pressure receiving element that applies pressure at right angles to rotationally displace the first lever in a first direction around the rotation point, and is attached to the distal end of the first lever directly or via a lever; Pressure is applied to the end portion at right angles to the axial direction of the first lever in a direction opposite to the input pressure receiving element, and the first lever is rotationally displaced in the first direction around the rotation point. a footback pressure receiving element, a nozzle attached to a support plate so as to be rotatable around its axis, and a pin protruding at right angles to the longitudinal axis direction at its tip, and the pin is brought into contact with the pivot point, and the end a second lever rotatably disposed about the pivot point along the first lever such that the second lever forms a nozzle flap with the nozzle;
a leaf spring disposed between a substantially central position of the lever and the nozzle and pressing the second lever against the first lever at the pin position; and a plate spring that receives back pressure of the nozzle and outputs output pressure; an amplifier that applies this output pressure to the feedback pressure receiving element; and a rotation point position that changes the contact position between the pin on the first lever and the first lever and changes the rotation point of the first lever. A pneumatic ratio setting device equipped with a setting means.