SOLENOID VALVE WITH NOZZLE

• US 3,731,881 A
• Filed: 02/24/1972
• Issued: 05/08/1973
• Est. Priority Date: 02/24/1972
• Status: Expired due to Term

• Current Assignee: Edward D. Sigl, Robert W. Herr, Thomas E. Dixon
• Original Assignee: Edward D. Sigl, Robert W. Herr, Thomas E. Dixon
• Inventors: Dixon, Thomas E., Herr, Robert W., Sigl, Edward D.
• Primary Examiner(s): Ward, Jr., Robert S.
• Application Number:
  US05/229,118
• Time in Patent Office: 439 Days
• Field of Search: 251/139 239/585
• US Class Current: 239/585.3
• CPC Class Codes: F02M 2200/505 Adjusting spring tension by sliding spring seats
• CPC Class Codes: F02M 2200/507 Adjusting spring tension by screwing spring seats
• CPC Class Codes: F02M 51/0646 the valve being a short body, e.g. sphere or cube
• CPC Class Codes: F02M 51/0653 the valve being an elongated body, e.g. a needle valve
• CPC Class Codes: F02M 51/0657 the body being hollow and its interior communicating with the fuel flow
• CPC Class Codes: F02M 51/08 specially for low-pressure fuel-injection
• CPC Class Codes: F16K 31/0651 the fluid passing through the solenoid coil
• CPC Class Codes: F16K 31/0655 Lift valves

Abstract

A fuel injection valve having a hollow plastic nozzle with a discharge orifice at its front end, and a plastic bobbin with a hollow barrel and spaced flanges, the nozzle and barrel being in spaced alignment, and a coil surrounding the barrel between the flanges. A valve plunger in the nozzle is movable between closed and opened positions and has a front end which closes the orifice in the closed position, the plunger forming a first fluid passage communicating with the orifice. A magnetic casing surrounds a part of the nozzle and the bobbin and coil, and holds the nozzle and bobbin in assembled relation, the casing having a portion bridging the space between the nozzle and barrel. An armature is attached to the rear end of the plunger and has a portion extending into the space between the nozzle and bobbin and defining a first, fixed airgap with the bridging portion of the casing, the armature also forming a second fluid passage communicating with the first passage. A magnetic core is positioned in the barrel and forms a second airgap with the armature in its closed position, the core, casing and armature forming a magnetic circuit for the coil. The core forms a third fluid passage communicating with the second passage, and a spring normally biases the armature and plunger to the closed position. The core is secured to the casing, and the casing includes an inlet conduit communicating with the third passage.

Claims

1. A solenoid valve comprising:

a hollow nozzle member formed of non-magnetic material and having a front end with a discharge orifice formed therein, and an open rear end;

a bobbin member formed of non-magnetic material and including a hollow barrel portion having open front and rear ends, and spaced flange portions formed on said barrel portion, said nozzle member and said barrel portion being in alignment with said rear end of said nozzle member spaced from said front end of said barrel portion;

a coil surrounding said barrel portion between said flange portions;

a valve plunger in said nozzle member axially movable between closed and open positions and having a front end which closes said orifice in said closed position, and a rear end, said plunger forming a first fluid passage communicating with said orifice in said open position;

casing means formed of mAgnetic material and surrounding a part of said nozzle member and said bobbin member and coil for holding said nozzle member and bobbin member in assembled relation, said casing means having a portion bridging the space between said rear end of said nozzle member and said front end of said barrel portion of said bobbin member;

a disc armature member formed of magnetic material at said rear end of said plunger and movable therewith, said armature having a portion extending into said space defining a first, fixed airgap with said casing means bridging portion, said armature forming a second fluid passage communicating with said first passage;

a core member formed of magnetic material in said barrel portion and forming a second airgap with said armature in said closed position;

said core member, casing means and armature forming a magnetic circuit for said coil whereby said armature is moved toward said core and said plunger is moved to said open position upon energization of said coil, said core forming a third fluid passage communicating with said second fluid passage;

spring means normally biasing said armature and plunger to said closed position; and

means for securing said core to said casing means;

said casing means including an inlet conduit portion communicating with said third passage whereby fluid flows from said inlet conduit through said passages and orifice upon energization of said coil.

2. The valve of claim 1 further comprising means on a respective end of one of said nozzle member and barrel portion and engaging the other for forming said space.

3. The valve of claim 2 wherein said space forming means comprises spaced fingers, said armature having a plurality of portions respectively extending between said fingers.

4. The valve of claim 1 wherein said plunger is at least partially spaced from the interior wall of said nozzle thereby forming said first passage, said armature having recesses formed in said portion thereby forming said second passage, said core being at least partially spaced from the interior wall of said barrel portion thereby forming said third passage.

5. The valve of claim 1 wherein said securing means secures said core to said inlet conduit.

6. The valve of claim 5 wherein said core is elongated and has front and rear ends with said front end forming said second airgap, said securing means being adjacent said rear end of said core.

7. The valve of claim 6 further comprising means for adjustably connecting said core to said securing means thereby selectively to adjust said second airgap.

8. The valve of claim 7 wherein said connecting means comprises a threaded connection.

9. The valve of claim 6 wherein said core is spaced from the interior wall of said barrel portion thereby forming a part of said third passage, said securing means having the remaining part of said third passage formed therein.

10. The valve of claim 9 wherein said spring means is a coil spring surrounding said core and acting between said armature and said securing means.

11. The valve of claim 10 further comprising means for adjustably connecting said securing means to said inlet conduit thereby selectively to adjust the spring rate of said spring.

12. The valve of claim 11 wherein said connecting means comprises a threaded connection.

13. The valve of claim 10 wherein said securing means comprises a sleeve having a front portion extending into said barrel portion and a rear portion extending into said inlet conduit, said spring acting against said front end of said sleeve, said rear end of said sleeve having a threaded connection with said inlet conduit thereby selectively to adjust the spring rate of said spring, said rear end of said core having a threaded connection with said front end of said sleeve thereby selectively to adjust said second airgap.

14. The valve of claim 1 wherein said inlet conduit has a front portion extending into said barrel portion and a rear portion, said core being within and spaced from said inlet conduit thereBy forming said third passage, said core being elongated and having front and rear ends, said front end of said core forming said second airgap, said securing means being formed on said rear end of said core and being connected to said rear portion of said inlet conduit.

15. The valve of claim 14 wherein said front portion of said inlet conduit has spaced projections thereon engaging and supporting said front end of said core.

16. The valve of claim 14 wherein said securing means comprises an enlarged portion formed on said rear end of said core, said enlarged portion having indentations in its outer periphery communicating between said third passage and said rear portion of said inlet conduit, said rear portion of said inlet conduit being crimped to said enlarged portion.

17. The valve of claim 1 wherein said armature has a central opening formed therethrough said plunger member having a central opening formed in its rear end communicating with said armature opening, said plunger opening having a front end, said core having a front end forming said second airgap with said armature, said spring means comprising a coil spring in said openings acting between said front end of said plunger opening and said front end of said core.