JPS6135930Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a dial-type level meter with an alarm contact mechanism, and more particularly to a dial-type level meter suitable for variably adjusting the set value and cutoff difference of the alarm contact.

FIG. 1 shows a conventional dial type level meter, which will be explained below.

In the figure, 1 is a float that moves according to the fluctuations in the liquid level of the object to be measured 2, and one end of this float 1 is connected to the other end of a wire 3 wound around a wire winding pulley 4. The vertical linear movement of the float 1 is converted into the rotational movement of the wire winding pulley 4. The wire winding pulley 4 includes a leaf spring pulley 5 as shown in FIG.
One end of a leaf spring 6 is wound around this leaf spring pulley 5, and the other end of the leaf spring 6 is wound around a leaf spring winding pulley 7. The wire winding pulley 4 is always urged in the direction of winding the wire 3 by the leaf spring 6, so that the wire 3 can be wound without slack when the float 1 is raised. When the float 1 descends, the weight of the float 1 overcomes the spring force of the leaf spring 6 and descends, and the wire winding pulley 4 rotates accordingly.

As shown in FIG. 1, the rotating shaft 8 of the wire winding pulley 4 includes a cam 10 for operating a micro switch 9 and a scale plate 11 that is calibrated in accordance with the liquid level of the object 2 to be measured. An indicator needle 12 is provided respectively. The wire winding pulley 4 rotates in accordance with the vertical linear movement of the float 1, and the liquid level is indicated on the scale plate 11 via the level indicator needle 12, and the wire rolls on the surface of the cam 10. The micro switch 9 is actuated via the micro switch roller 13 and lever 14, and an alarm contact signal is output from the micro switch 9.

Figure 2 shows cam 1 in response to up and down fluctuations in the liquid level.
It shows the relationship between the position of 0 and the operating state of the microswitch 9. In the figure, the solid line graph indicates the microswitch 9 is on, and the broken line graph indicates the microswitch 9 is off. The operation will be explained below based on FIG.

When the liquid level is low, part a of the cam 10 shown in FIG. 1 corresponds to the roller 13, and the microswitch 9 is in the OFF state due to force being applied via the roller 13 and lever 14.

The liquid level rises and part b of the cam 10 moves to the roller 1.
When the position corresponding to 3 is reached, the force applied to the microswitch 9 via the roller 13 and the lever 14 is removed, and the microswitch 9 is therefore in the on state. When the liquid level rises further and the c part of the cam 10 comes to the roller 13 position, the force on the micro switch 9 is still removed, so the micro switch 9 remains in the on state. .

Next, when the liquid level falls and the part b of the cam 10 reaches the roller 13 position, force is again applied to the micro switch 9 via the roller 13 and lever 14, but when the liquid level rises, the micro switch 9 is turned off. The state changes from the on state to the off state at a position where the state changes from the on state, that is, at a position B' which is not the same as the point B in FIG. 2 but is slightly shifted below. When the liquid level falls further and part a of the cam 10 corresponds to the roller 13, the force applied to the micro switch 9 is not removed, and therefore the micro switch 9 is in the OFF state. is maintained.

Here, the difference between point B and point B' is called the cutting difference,
Although it is a small value, it is a fixed value determined by the structure of the microswitch.

In the conventional dial level meter with the above configuration, depending on the application, such as using the alarm contact signal output from the micro switch to control the pump or regulating valve, it is necessary to make the cutoff difference large and variable. There is.

In such cases, conventionally, two microswitches with different B points, or set values, are used, and an electrically complex circuit is combined with the two microswitches to obtain an appropriate cutting difference. I have to.

However, this type of method has drawbacks such as increased cost and reduced reliability due to the use of two microswitches and a complicated electric circuit as described above.

The present invention was devised to solve these conventional problems, and its purpose is to provide a dial level meter that can appropriately adjust the cutting difference with a single micro switch. .

The present invention focuses on the fact that the conventional difficulty was that the route for guiding the position detector of the alarm contactor was the same when the level was rising and when the level was falling.
The route is changed when the level rises and when the level falls, thereby making the set value and disconnection difference of the alarm contact variable.

The present invention will be explained below based on an embodiment shown in FIGS. 3 to 5.

In FIG. 3, reference numeral 1 denotes a float that moves according to the vertical fluctuations in the liquid level of the object to be measured 2, and this float 1 has one end connected to a wire 3 wound around a wire winding pulley 4, and the other end of the float 1. The vertical linear movement of the float 1 is converted into the rotational movement of the wire winding pulley 4. As shown in FIG. 3, the wire winding pulley 4 is integrally provided with a leaf spring pulley 5, and one end of a leaf spring 6 is wound around the leaf spring pulley 5. 6
The other end is wound around a pulley 7 for winding up a leaf spring. The wire winding pulley 4 is always urged in the winding direction of the wire 3 by the leaf spring 6, so that the wire 3 can be wound without slack when the float 1 is raised. When the float 1 descends, the weight of the float 1 overcomes the biasing force of the leaf spring 6 and descends, and the wire winding pulley 4 rotates accordingly.

As shown in FIG. 1, the rotating shaft 8 of the wire winding pulley 4 is provided with a level indicator 12 of a scale plate 11 that is graduated in correspondence with the liquid level of the drum 15 and the object to be measured 2. It is being An operating mechanism 16 for operating the micro switch 9 is attached to the drum 15. Due to the rotational movement of the wire winding pulley 4 in accordance with the vertical linear movement of the float 1, the liquid level is indicated on the scale plate 11 via the level indicator needle 12, and the wire is rolled on the operating mechanism 16. The micro switch 9 is actuated via the micro switch roller 13 and lever 14, and an alarm contact signal is output from the micro switch 9.

As shown in FIG.
The rails 17, 20, 21 are fixed to the drum 15 via screws 22, and the rail 19 is connected to the rail 1 by a spring 23.
It is pressed against part a of 7. Therefore, the roller 13 of the micro switch 9 can move from the section a of the rail 17 via the rails 19 and 20 toward the section b of the rail 21, but cannot move from section a to section d. In addition, since the lever 14 of the micro switch 9 is always urged toward the operating mechanism 16 by the spring 24 for the micro switch 9, the roller that has moved from section b to section c on the rail moves from section c to section d. can move, but cannot move from part c to part b.

FIG. 6 shows the relationship between the position of the actuating mechanism 16 and the operating state of the microswitch 9 in response to vertical fluctuations in the liquid level, and the operation will be explained below with reference to this.

When the liquid level is low, part a of the rail 17 corresponds to the roller 13, and the micro switch 9
is in the off state due to a force being applied via the lever 14.

When the liquid level rises, the roller 13 is guided on the rail from part a to part b, and when part b corresponds to the roller 13, it is applied to the micro switch 9 via the roller 13 and lever 14. The applied force is removed and the micro switch 9 is turned on. Point B in FIG. 4 corresponds to this.

Even when the liquid level rises further and the part c of the rail corresponds to the roller 13, the force applied to the microswitch 9 is still removed and the on state is maintained. The range from point B to point c in FIG. 4 corresponds to this.

When the liquid level drops from point c in Fig. 4, the roller 13 moves on the rail from point c to d.
The micro switch 9 is turned off only when the d part of the rail corresponds to the roller 13.
becomes. Point D in FIG. 4 corresponds to this.

When the liquid level drops further, the rail 19 is pushed open against the spring 23 and guided from section d toward section a. The range from point D to point A in FIG. 4 corresponds to this.

As explained above, this embodiment provides the following effects.

(1) The cutting difference is the difference between point B and point D, and can be set to an appropriate value.

(2) Setting values and cutting differences can be varied by appropriately adjusting the mounting position of each rail.

In the above embodiment, a mechanical microswitch is used as the alarm contact, but an optical or electrical contact may be used. Further, in the embodiment described above, the case where the operating mechanism is configured by a rail has been described, but a groove may be used instead.

The present invention has been described above based on a preferred embodiment, but according to the present invention, the cutting difference and set value can be appropriately adjusted with one microswitch, and the range of applications can be expanded.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing a conventional example, Fig. 2 is an explanatory view showing the operating state of the microswitch, Fig. 3 is a perspective view showing an embodiment of the present invention, and Fig. 4 is a plan view of the operating mechanism. 5 is a sectional view taken along the line -- in FIG. 4, and FIG. 6 is an explanatory diagram showing the operating state of the microswitch. 1... Float, 2... Measured object, 3... Wire, 4... Wire winding pulley, 8... Rotating shaft,
9...Micro switch, 11...Scale plate, 12
... Level indicator needle, 13 ... Roller, 16 ... Actuation mechanism, 17, 19, 20, 21 ... Rail, 1
8... Hinge, 22... Screw, 23, 24... Spring.

Claims (1)

[Scope of utility model registration request] Converts the vertical linear motion of the float, which is displaced as the liquid level of the object to be measured changes, into rotational motion,
In a dial type level meter that indicates the liquid level on a scale plate and operates an alarm contactor via an operating mechanism, a path of the operating mechanism for guiding the position detector of the alarm contactor, A dial type level meter that is characterized by having separate paths when the level rises and when the level falls.