JPH0451273Y2 - - Google Patents

Description

[Detailed Description of the Invention] Purpose of the Invention (Field of Industrial Application) The present invention relates to an electromagnetic valve that can change the opening/closing stroke amount of a poppet valve.

(Prior Art) In conventional electromagnetic valves used in hydraulic or pneumatic systems, the stroke amount of a piston that is attracted by a solenoid coil and a poppet valve that is operatively connected to the piston and driven to open and close is structurally specific. Therefore, it is not possible to change the opening/closing stroke amount of the poppet valve, and therefore it is impossible to change the fluid passage cross-sectional area when the valve is opened. Therefore, the conventional pulse width modulation method cannot control the flow rate when the duty is 100% or higher.

Also, if you want to perform variable control of the flow rate when the solenoid valve's duty is 100% or more, it is necessary to combine a solenoid valve that controls a large flow rate with a variable throttle valve, or to connect multiple solenoid valves in parallel. complication of the system and an increase in cost are unavoidable.

(Problems to be Solved by the Invention) Therefore, an object of the present invention is to provide an electromagnetic valve that can solve the above-mentioned problems in variable control of fluid flow rate using conventional electromagnetic valves.

Structure of the Invention (Means for Solving Problems) Therefore, in the present invention, a valve body is provided with a plurality of ports, a poppet valve is provided so as to be movable towards and away from the fluid passage opening formed between the ports, and In the electromagnetic valve, the poppet valve is operatively connected to a piston driven by excitation and demagnetization of a solenoid coil, and the poppet valve is moved in stroke based on the slide stroke of the piston to open and close the fluid passage port, the valve body having a poppet valve. A plurality of electromagnetic solenoid parts are coaxially arranged in series in the opening/closing stroke direction of the poppet valve, and each of the electromagnetic solenoid parts is arranged in a solenoid coil so as to be slidable in the opening/closing stroke direction of the poppet valve, and the coil, etc. and a guide core that slides and guides the tip of the piston in the opening/closing stroke direction of the poppet valve. The tip of the piston of the solenoid section is operatively connected to a poppet valve, the tip of the piston of the other electromagnetic solenoid section is operatively connected to the piston of an adjacent electromagnetic solenoid section on the poppet valve side of the electromagnetic solenoid section,
Further, the set stroke amounts of the respective pistons are made different, and an adsorption prevention means is interposed between each of the guide cores and each piston.

(Operation) That is, by energizing any one of the plurality of electromagnetic solenoid parts, the poppet valve is moved in the opening direction by a distance equal to the set stroke amount of the piston of the solenoid part, and the poppet valve is moved through the electromagnetic valve. The amount of fluid is controlled in accordance with the opening stroke amount of the poppet valve. Therefore, by appropriately selecting the excitation and demagnetization of the plurality of electromagnetic solenoids, the fluid flow rate can be variably controlled, and when the fluid flow rate is to be variably controlled, by employing such an electromagnetic valve, the variable throttle valve can be controlled. It is possible to omit or reduce the number of electromagnetic valves used. Moreover, the fluid flow rate adjustment controls the opening/closing stroke amount of the poppet valve.
That is, since this method is based on controlling the cross-sectional area of fluid passing through an opening opened and closed by a poppet valve, pressure fluctuations are reduced compared to fluid flow rate control using the conventional pulse width modulation method. Further, when the poppet valve starts to open, the plurality of electromagnetic solenoids are excited all at once to generate a large driving force, so that the poppet valve is opened at high speed, and the fluid supply is controlled in a short time. This is particularly effective in such cases. Further, the adhesion prevention means prevents the guide core from adhering to the piston which is in a pressing state against the poppet valve.

(Example) Hereinafter, examples 1 to 3 that embody the present invention will be described.
This will be explained based on the diagram.

Reference numeral 1 denotes a valve body having an input port 2 and an output port 3, and a plug 4 is screwed into the upper opening of the valve body. A sleeve 5 is housed and fixed within the valve body 1, and a poppet valve 6 is housed within the sleeve 5 so as to be slidable in the vertical direction. A pressure spring 7 is housed in the accommodation recess 1a formed in the inner bottom surface of the valve body 1, and the poppet valve 6 is configured to always close the fluid passage port 5a by the pressure force of the pressure spring 7. There is. The downward movement of the poppet valve 6 is regulated by its lower end surface coming into contact with the inner bottom surface of the valve body 1.

A housing cylinder 8 is fitted and fixed in the plug 4, and a first solenoid coil 9 is housed in the upper inner peripheral surface of the cylinder 8. Note that 9a is a lead wire electrically connected to the solenoid coil 9. Further, a sleeve 10 consisting of a small diameter portion 10a and a large diameter portion 10b is fitted and accommodated in the housing cylinder 8, and the small diameter portion 10a is disposed within the solenoid coil 9. A first piston 11 is housed in the small diameter portion 10a so as to be slidable in the sliding direction of the poppet valve 6, and is supported by a pressure spring 12 interposed between the piston 11 and the upper wall surface of the small diameter portion 10a. The piston 11 is urged downward. Then, a small diameter portion 10 below the piston 11
A guide core 13 is fitted from inside a to the upper part of the large diameter portion 10b, and the guide core 13 is inserted into the rod 1 of the piston 11.
1a is slidably guided, and as the solenoid coil 9 is excited, the piston 11 is attracted. That is, the solenoid coil 9, the piston 11, and the guide core 13 constitute a first electromagnetic solenoid section S1. A stopper 14 as an adhesion prevention means made of a non-magnetic material is fixedly attached to the upper surface of the guide core 13, and prevents the piston 11 from stopping and preventing the piston 11 and the guide core 13 from adhering to each other. There is.

A non-magnetic material 15 is contained in the sleeve 10 inside the first solenoid coil 9, and serves to increase the attraction force between the piston 11 and the guide core 13.

A second solenoid coil 16 is housed inside the lower part of the plug 4, and the solenoid coil 1
A sleeve 17 consisting of a small diameter portion 17a and a large diameter portion 17b is fitted and housed inside the sleeve 6. A second piston 1 is disposed within the small diameter portion 17a of the sleeve 17.
8 is housed so as to be slidable in the same direction as the sliding direction of the first piston 11, and a piston rod 11a of the first piston 11 is disposed on the upper surface of the piston rod 11a.
The lower end of can be touched. Note that 16a is a lead wire electrically connected to the solenoid coil 16. A guide core 19 is fitted below the second piston 18 from the small diameter part 17a to the large diameter part 17b of the sleeve 17, and slides and guides the rod 18a of the second piston 18, and also guides the second solenoid coil. When the piston 16 is excited, the second piston 18 is attracted. That is, the second solenoid coil 16, the second piston 18, and the guide core 19
An electromagnetic solenoid section S2 is configured. The lower end of the piston rod 18a is connected to the poppet valve 6.
It can be brought into contact with the upper end at all times, and when the solenoid coil 9 or 16 is energized, the poppet valve 6 is moved downward against the pressing force of the pressing spring 7, and the fluid passage port 5a is opened. It's getting old.

In this embodiment, as shown in FIG.
When the piston 11 closes the fluid passage port 5a, the lower end of the piston rod 11a of the upper piston 11 is pressed onto the lower piston 18 by the pressure spring 12, and the lower end of the upper piston 11 and the upper end of the stopper 14 The gap distance, that is, the movable distance L1 of the upper piston 11, and the movable distance L2 of the lower piston 18, that is, the gap distance between the lower end of the poppet valve 6, which is the maximum stroke of the poppet valve 6, and the inner bottom surface of the valve body 1 are L1. <There is a relationship of L2. Further, the gap distance between the lower end of the second piston 18 and the upper end of the guide core 19 is set larger than the movable distance L2, so that when the lower end of the poppet valve 6 comes into contact with the inner bottom surface of the valve body 1, the piston 18 A space is formed between the guide core 19 and the guide core 19 as a means for preventing adsorption.

A non-magnetic material 20 is contained in the sleeve 17 inside the lower solenoid coil 16, and serves to increase the attractive force between the lower piston 18 and the guide core 19.

Further, a non-magnetic material 21 is interposed between the guide core 13 and the sleeve 17, and together with a non-magnetic material 32 contained in the sleeve 10 corresponding to the same portion, the upper electromagnetic solenoid section S1 and the lower electromagnetic solenoid Mutual influence due to magnetic force between the part S2 and the part S2 is suppressed.

Now, when the upper solenoid coil 9 in the electromagnetic valve configured as described above is excited,
As shown in FIG. 2, the upper piston 11 is suctioned toward the guide core 13 and stopped by the stopper 14. As a result, the poppet valve 6 is moved down by the stroke amount L1 of the piston 11, and the fluid passage port 5a is opened. On the other hand, when the lower solenoid coil 16 is energized, the lower piston 18 is attracted and moved toward the guide core 19 as shown in FIG. It is moved downward. That is, the poppet valve 6 is moved down by the stroke amount L2 of the piston 18, and the fluid passage port 5a is opened.
At this time, as shown in FIG. 3, the piston 18 and the guide core 19 are spaced apart slightly to avoid adhesion between them, and the return resistance to the poppet valve 6 due to such adsorption is eliminated.

Due to such a difference in the opening/closing stroke amount of the poppet valve 6, the fluid passage cross-sectional area at the fluid passage port 5a differs, and the fluid flow rate can be controlled in two ways with only one electromagnetic valve of this embodiment. Therefore, if the electromagnetic valve of this embodiment is used in a system that changes the fluid flow rate in two ways, only one valve is required.
Not only can the number of electromagnetic valves used be reduced, but also a variable throttle valve is no longer required, making it possible to simplify the system and reduce costs. Moreover, if the first electromagnetic solenoid section S1 is considered as a conventional single electromagnetic valve, the duty in the electromagnetic solenoid section S1 can be increased by energizing the second electromagnetic solenoid section S2.
It provides excellent performance not found in conventional electromagnetic valves, being able to control flow rates above 100%. The control to change the fluid passage cross-sectional area of the fluid passage port 5a is not limited to simply controlling the fluid flow rate, but also enables pressure adjustment.

In addition, both upper and lower solenoid coils 9, 1
If solenoid coils 6 are energized at the same time, a much larger driving force can be obtained than when only one solenoid coil is energized, and the poppet valve 6 can be opened at a higher speed. Therefore, not only can the fluid flow rate be controlled with the opening/closing stroke amount of the poppet valve 6 being L2, but also the fluid flow rate can be controlled with the opening/closing stroke amount being L1 by appropriately setting the excitation time of the lower solenoid coil 16. The responsiveness in the opening operation of the poppet valve 6 can be improved without making the opening/closing stroke amount of the poppet valve 6 greater than L1.

According to the control for changing the liquid passage cross-sectional area in the fluid passage port 5a of this embodiment, for example, the fluid passage port 5a
By controlling the opening/closing stroke amount of the poppet valve 6 to be switched between L1 and L2 while keeping it open, pulsation is suppressed compared to the conventional duty variation method in which the fluid passage cross-sectional area of the fluid passage opening is constant. be able to. Alternatively, when closing the liquid passage port 5a, for example, when closing from the open state where the stroke amount is L2, the electromagnetic solenoid portion S1
It is also possible to suppress pressure fluctuations and reduce pulsation by energizing the poppet valve 6 and braking the poppet valve 6.

Of course, the present invention is not limited to the above-mentioned embodiment. For example, as shown in FIG. 4, the same solenoid coils 22, 23, 2
4. It is also possible to construct the electromagnetic solenoid parts S3, S4, S5 by stacking the pistons 25, 26, 27 and guide cores 28, 29, 30 of the same diameter. The interval between changes in the opening/closing stroke amount can be made even finer, and fine flow control and pressure control can be performed depending on the situation. Furthermore, since the solenoid coils 22, 23, and 24 have the same diameter, the number of solenoid coils can be changed as necessary by replacing plugs with plugs of different lengths. Therefore, various opening/closing stroke amounts of the poppet valve can be obtained without preparing many types of electromagnetic valves, and costs can be reduced.

In addition, 14A and 14B in the figure are stoppers 15A, 15B, 1 that prevent the piston and the guide core from adhering to each other, similar to the stopper 14 in the above embodiment.
5C is a non-magnetic material 21A, 32A, and 21 which acts to increase the attraction force between the piston and the guide core, similar to the non-magnetic material 15, 20 in the above embodiment.
Similar to 21 in the embodiment described above, B and 32B prevent mutual action due to magnetic force between the respective electromagnetic solenoid parts. Further, 31 is a bundle of lead wires electrically connected to each of the solenoid coils 22, 23, and 24.

Effects of the invention As detailed above, in the electromagnetic valve of the invention, in particular, the set stroke amount of each piston is made different, so the opening/closing stroke amount of the poppet valve relative to the fluid passage port can be changed. With a simple configuration, it is possible to easily change the cross-sectional area of the fluid passage when the valve is opened, and since a suction prevention means is interposed between each guide core and each piston, suction to the guide core side can be easily changed. It is possible to avoid adhesion of the piston to the guide core during operation, and to eliminate the return resistance of the poppet valve due to such adsorption, thereby achieving the excellent effect of smoothly controlling the opening and closing of the poppet valve.

[Brief explanation of the drawing]

Figures 1 to 3 show an embodiment embodying the present invention, with Figure 1 being a longitudinal sectional view showing the closed state, and Figure 2 being a longitudinal sectional view showing the first electromagnetic solenoid section being energized. 3 is a longitudinal sectional view showing a state in which the second electromagnetic solenoid section is excited, and FIG. 4 is a longitudinal sectional view showing another example of the present invention. Poppet valve...6, Electromagnetic solenoid part...S
1, S2, S3, S4, S5.

Claims (1)

[Claims for Utility Model Registration] A valve body is provided with a plurality of ports, a poppet valve is provided so as to be movable toward and away from a fluid passageway formed between the ports, and the poppet valve is driven by excitation and demagnetization of a solenoid coil. In the electromagnetic valve that is operatively connected to a piston that moves the poppet valve based on the sliding stroke of the piston to open and close the fluid passage port, the valve body 1 includes a plurality of electromagnetic valves in the opening and closing stroke direction of the poppet valve 6. The solenoid parts S1, etc. are coaxially arranged in series, and each of the electromagnetic solenoid parts S1, etc. is arranged so as to be slidable in the opening/closing stroke direction of the poppet valve 6 in the solenoid coil 9, etc., and the coil 9, etc. Each of the pistons 11, etc. is configured to include a piston 11, etc., which is driven based on excitation and demagnetization, and a guide core 13, etc., which slides and guides the tip end 11a, etc. of the piston in the opening/closing stroke direction of the poppet valve 6, and each of the pistons 11, etc. Among them, the tip of the piston of the electromagnetic solenoid section adjacent to the poppet valve 6 is operatively connected to the poppet valve 6, and the tip of the piston of the other electromagnetic solenoid section is connected to the adjacent electromagnetic solenoid section on the poppet valve side of the electromagnetic solenoid section. A suction prevention means 14, etc. is operatively connected to the piston of the solenoid section, and furthermore, the set stroke amount L1, etc. of each piston 11, etc. is made different, and adsorption prevention means 14, etc. are provided between each guide core 13, etc. and each piston 11, etc. A solenoid valve with a .