JPH02217706A - flow control nozzle - Google Patents

Abstract

PURPOSE:To stop the rotation of a return fluid in a return hole or return flow channel and prevent the growth of an air column and the air entanglement by forming a plurality of return holes round the central axis of a distributor. CONSTITUTION:A flow rate control nozzle 1 is constituted with a distributor 3 which forms a return flow channel 2 in its central section and orifice disc 5 which forms a swirl chamber 4 with the distributor 3, and a section 6 to stop air entanglement is formed in the shape of a plane on the plane which enters the swirl chamber 4 round the central axis of the distributor 3 and at the same time two return holes 7 are formed symmetrically outside of the section 6 to stop air entanglement at a position offset from the central axis of the distributor 3. Accordingly in the nozzle 1 the section 6 to stop air entanglement prevents the air that exists in the central section of the spray from advancing into the return holes 7 and return flow channel 2 without disturbing the swirl motion in the swirl chamber and at the same time the fuel is returned by the return holes 7, and it is possible to prevent the air entanglement which is generated by the advance of the swirl of spray into the return holes 7 and return flow channel 2.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a return type flow rate control nozzle used in oil water heaters and the like.

(Prior Art) Conventionally, this type of flow rate control nozzle consists of a distributor that forms a return flow path, and an orifice disk that forms a swirling chamber with the distributor.
The oil spray amount is controlled by changing the return flow rate, and the flow rate adjustment range, which is the ratio between the maximum spray n]t and the minimum spray amount under predetermined conditions, is 1/3.5 to l/3. 7 or so are known.

Here, the minimum spray amount refers to the spray amount that, if narrowed down any further, will result in an inappropriate combustion state.

(Problems to be Solved by the Invention) In the conventional technology described above, when the minimum spray amount is reduced beyond the flow rate adjustment range in order to apply it to a small household oil water heater, the spray pattern changes, and As the spray angle increases, air is drawn into the return flow path, causing pulsation of the spray, which causes combustion to become unstable, producing soot and odors, resulting in inappropriate combustion conditions. Was.

The present invention has been made in view of the above-mentioned problems of the conventional technology, and its purpose is to provide a flow rate adjustment range of at least 1/(approximately 5 or more) under predetermined conditions. It is possible to finely control the amount of spray that can be used in direct-pressure petroleum instant water heaters, and by maintaining the spray pattern and spray angle in an optimal state, the combustion performance does not change and there is no air intrusion. Therefore, it is an attempt to provide a quiet flow control nozzle that does not cause vibration combustion.

(Means for Solving the Problems) In order to solve the above problems, the present invention has a plurality of return holes that communicate the return passage and the swirling chamber formed at positions eccentric from the center axis of the distributor facing the swirling chamber. It is.

Alternatively, the needle may be fitted into the distributor so as to face the return hole from the return flow path.

Furthermore, a flow rate regulating valve may be provided in the return flow path.

(Function) The present invention configured as described above has a plurality of return holes formed around the center axis of the distributor, thereby preventing the return fluid from swirling in the return holes or the return flow path, thereby preventing the growth of air columns. Therefore, air entrainment does not occur.

Further, even if the needle is fitted into the distributor, fine flow control can be performed over a wide range.

Furthermore, fine control of the spray amount over a wide range is possible by controlling the position of the flow rate regulating valve provided in the return flow path.

(Example) Embodiments of the present invention will be described below based on the accompanying drawings.

FIGS. 1 and 2 are a vertical cross-sectional view and a cross-sectional view of a main part of a flow control nozzle according to the present invention.

The flow rate control nozzle 1 shown in FIGS. 1 and 2 is composed of a distributor 3 having a return passage 2 in its center, and an orifice disk 5 forming a swirling chamber 4 with the distributor 3.

The flow rate control nozzle 1 shown in FIGS. 1 and 2 has an air entrainment prevention part 6 and a return hole 7 formed in a distributor 3.

The nozzle 1 shown in FIG. 1 has an air entrainment prevention part 6 formed in a planar shape on the surface facing the swirling chamber 4 around the center axis of the distributor 3, and an air entrainment prevention part 6 which is located outside the air entrainment prevention part 6 and which is located outside the distributor 3. The return holes 7 are formed symmetrically with respect to the central axis of the return holes 7.

The nozzle 1 shown in FIG. 2 has a recess 8 formed in the surface of the distributor 3 of the nozzle 1 shown in FIG. 1, where the air entrainment prevention part 6 and the return hole 7 are formed.

Therefore, in the nozzle 1 shown in FIGS. 1 and 2, the planar air entrainment prevention part 6 formed around the center axis of the distributor 3 does not hinder the swirling movement in the swirling chamber, and the air present in the center of the spray can be removed. It prevents it from entering the return hole 7 and return flow path 2. Furthermore, the fuel is returned by making the return hole 7 eccentric from the central axis of the distributor 3 and forming a plurality of holes smaller than conventional ones in concentric positions, thereby eliminating the need for a needle. Furthermore, since a plurality of return holes 7 are formed, air entrainment caused by swirling of the jet n entering the return hole 7 or the return flow path 2 is prevented from occurring.

In addition, the nozzle 1 shown in FIG. 2 has a concave portion 8 formed at the tip of the distributor 3 to enlarge the swirling chamber, reduce the swirling component at the time of maximum spraying, and increase the maximum spray amount.

Therefore, the maximum spray amount can be increased without changing the nozzle capacity or the minimum spray amount n.

The flow rate control nozzle 20 shown in FIG. 3(^) is shown in FIG. 1 so that the tips 21a and 21a of the needle 21 shown in FIGS. It is fitted into the distributor 3 so that it can move forward and backward. Further, a microactuator 22 for driving the needle 21 and a position sensor 23 for detecting the position of the needle 21 are provided to move the needle 21 back and forth to control the amount of spray.

That is, the flow rate control nozzle 20 is constructed by fitting the screw bin 26 in which the orifice disk 5 and the distributor 3 are fitted into the nozzle body 25, inserting the needle 21 in a slidable manner, and screwing the nozzle body 25 into the adapter 27. In addition, it is configured to include a microactuator 22 and a position sensor 23.

Therefore, by driving the micro-actuator 22, the needle 2] can be precisely positioned, making it possible to finely control the amount of spray. This stabilizes the spray, allowing fine spray volume control and reducing the droplet volume adjustment range to 1/(
(approximately 5 or more).

Note that the spray amount can be controlled even when the needle 21 is fixed.

Furthermore, the flow rate control nozzle 30 shown in FIG.
It has been established. That is, by driving the microactuator 32 provided in the flow rate adjustment valve 31, the needle 33 of the flow rate adjustment valve 31 is finely positioned, the return flow rate is adjusted, and the spray amount can be finely controlled. Coupled with the planar shape of 6 and the formation of two return holes 7 eccentric from the central axis of the distributor 3, the spray is stabilized, allowing for fine spray 7i amount control and a flow rate adjustment range of 17 (approximately 5 or more). It can be expanded to still,
34 is a position sensor that detects the position of the needle.

(Effects of the Invention) As explained above, according to the present invention, a plurality of return holes are formed at eccentric positions around the center axis of the distributor, so swirling of spray in the return holes and return flow path is prevented, and air Since there is no entrainment or uneven return flow, the spray can be stabilized and the flow rate adjustment range can be reduced to 1/2.
(approximately 5 or more).

Further, even when the needle is fitted into the distributor, the same effect as described above can be obtained by further providing a flow rate adjustment valve in the return passage and controlling the position of the needle of the flow rate adjustment valve.

[Brief explanation of the drawing]

Figures 1 and 2 are longitudinal and cross-sectional views of the main parts of a flow rate control nozzle according to the present invention, Figure 3 is a flow rate control nozzle that allows the needle to move forward and backward, and Figure 4 is a return flow path. This is a flow control nozzle equipped with a flow rate adjustment valve. In addition, in the drawing, 1, 20, 30 are flow rate control nozzles, 2 is a return flow path, 3 is a distributor, 4 is a swirling chamber, 5
7 is an orifice disk, 7 is a return hole, 21 is a needle, and 31 is a flow rate regulating valve.

Claims (3)

[Claims] (1) In a flow control nozzle that is composed of a distributor that forms a return flow path in the center, and an orifice disk that forms a swirl chamber with the distributor, and that controls the spray amount by changing the return flow rate, the return flow path and the swirl A flow rate control nozzle characterized in that a plurality of return holes communicating with the swirling chamber are formed at positions eccentric from the center axis of the distributor facing the swirling chamber. (2) The flow rate control nozzle according to claim 1, wherein the needle is fitted into the distributor so as to face the return hole from the return flow path. (3) The flow rate control nozzle according to claim 1, wherein a flow rate regulating valve is provided in the return flow path.