Accumulator-type injection valve

Claim 2

A fuel injection valve comprising: a. a case defining a valve chamber therein; b. inlet means adapted to communicate said valve chamber with a source of fuel; c. outlet means adapted to communicate said valve chamber with the exterior of said case; d. mounting means in said chamber located intermediate said inlet means and said outlet means; e. check valve means contained within said valve chamber intermediate said mounting means and said outlet means adapted to control the flow of fuel through said outlet means, said check valve means being mounted by said mounting means; f. sleeve means intermediate said mounting means and said inlet means, said sleeve means being hollow so as to define g. an accumulator chamber therein, h. a single opening in the form of an accumulator outlet means in said sleeve means adapted to communicate the accumulator chamber with the exterior of said sleeve means, said sleeve means being otherwise free of openings communicating with said accumulator chamber; and, i. wherein said accumulator outlet means is cooperatively positioned in sealing contact with said mounting means whereby fuel leaking between said check valve means from said valve chamber will pass into said accumulator chamber through said accumulator outlet means when fuel pressure in the valve chamber is of greater magnitude than the fuel pressure in the accumulator chamber and wherein a reverse passage of fuel from the accumulator chamber to the valve chamber will occur when fuel pressure in the valve chamber is of lesser magnitude than the fuel pressure in the accumulator chamber.

Claim 3

The invention of claim 1 wherein said outlet means include an outlet and a valve seat and said check valve means comprise a valve head adapted to mate with said valve seat and thereby sealingly close said outlet, a stem extending from said head and spring means serving to maintain said outlet normally closed when fuel pressure in the valve chamber is low.

Claim 4

The invention of claim 2 wherein said mounting means comprise a collar and said stem extends through said collar, said stem and collar being cooperatively dimensioned to provide a loose sliding fit, thereby allowing a small amount of fuel to pass therebetween.

Claim 5

The invention of claim 3 wherein said spring means comprise a spring positioned between said collar and said head.

Claim 6

The invention of claim 4 wherein said sleeve means comprise a generally cylindrical sleeve having a closed outer end and an open inner end defining said accumulator chamber, said open inner end defining said accumulator outlet means and wherein said accumulator outlet means comprise an accumulator outlet having an inner end abutment surface, said abutment surface contacting said collar for compression of said spring as well as for sealing against said collar such that said collar forms a closure for said accumulator outlet means.

Claim 7

The invention of claim 5 wherein said sleeve has mounted therein a stop member posItioned to limit movement of said stem into said accumulator chamber.

Claim 8

The invention of claim 6 wherein said stop member has formed therein an axial passageway to permit leaked fuel to pass by said stop member into said accumulator chamber.

Claim 9

The invention of claim 5 wherein said sleeve has filter means thereon which cooperate with said case to provide an edge-type filter for the fuel passing into the case through said inlet means.

Claim 10

The invention of claim 8 wherein the outer surface of said sleeve contacts the inner surface of said case and wherein the filter means comprise a first and a second set of longitudinally extending grooves formed on the outer surface of said sleeve, said first set of grooves extending from said outer end only part way along the outer sleeve surface, said second set of grooves extending from said inner end only part way along the outer sleeve surface such that fuel entering said case through said inlet means will flow from the first to the second set of grooves between the sleeve outer surface and the case and thence to said valve chamber and thereby filter impurities from the fuel.

Claim 11

The invention of claim 5 wherein said abutment surface is conical and wherein said collar has a spherical face contacted by said abutment surface to form a liquidtight seal.

Claim 12

A fuel injection valve comprising: a. a case defining a valve chamber therein; b. inlet means adapted to communicate said valve chamber with a source of fuel; c. outlet means adapted to communicate said valve chamber with the exterior of said case; d. mounting means in said chamber located intermediate said inlet means and said outlet means; e. check valve means contained within said valve chamber intermediate said mounting means and said outlet means adapted to control the flow of fuel through said outlet means, said check valve means being mounted by said mounting means; f. sleeve means intermediate said mounting means and said inlet means, said sleeve means being hollow so as to define g. an accumulator chamber therein, h. a single opening in the form of an accumulator outlet means in said sleeve means adapted to communicate the accumulator chamber with the exterior of said sleeve means, said sleeve means being otherwise free of openings communicating with said accumulator chamber; i. said accumulator outlet means being cooperatively located in contact with said mounting means; and j. leak passage means in said mounting means adapted to restrictively intercommunicate said accumulator chamber with said valve chamber by way of said accumulator outlet means, whereby leakage of fuel from said valve chamber to said accumulator chamber will occur when fuel pressure in said accumulator chamber is less than that in said valve chamber, and a reverse leakage of fuel from said accumulator chamber to said valve chamber will occur when fuel pressure in said accumulator chamber is greater than that in the valve chamber.

Claim 13

A fuel injection valve comprising: a. a case defining a valve chamber therein; b. inlet means adapted to communicate said valve chamber with a source of fuel; c. outlet means adapted to communicate said valve chamber with the exterior of said case; d. mounting means in said chamber located intermediate said inlet means and said outlet means; e. check valve means contained within said valve chamber intermediate said mounting means and said outlet means adapted to control the flow of fuel through said outlet means, said check valve means being mounted by said mounting means; f. sleeve means intermediate said mounting means and said inlet means, said sleeve means being hollow so as to define g. an accumulator chamber therein, h. a single opening in the form of an accumulator outlet means in said sleeve means adapted to communicate the accumulator chamber with the exterior of said sleeve means, said sleeve means being otherwise free of openings communicating with said accumulator chamber; i. said accumulator outlet means being cooperatively located in contact with said mounting means; and j. leak passage means in said mounting means adapted to restrictively intercommunicate said accumulator chamber with said valve chamber by way of said accumulator outlet means, whereby leakage of fuel from said valve chamber to said accumulator chamber will occur when fuel pressure in said accumulator chamber is less than that in said valve chamber, and a reverse leakage of fuel from said accumulator chamber to said valve chamber will occur when fuel pressure in said accumulator chamber is greater than that in the valve chamber.

Claim 14

The invention of claim 11 wherein said valve means comprise a valve having a head portion normally sealingly closing said outlet, a stem portion extending from said head portion, a spring retainer mounted on said head portion, and spring means positioned between and contacting both said means defining a passage and said spring retainer, whereby said spring means serves to maintain said head portion in its position normally sealingly closing said outlet means.

Claim 15

The invention of claim 12 wherein said spring means is a spring and wherein said stem extends through said passage in closely fitting relation therewith, and wherein said head has an exposed undersurface whereby fuel pressure in said valve chamber acting on said exposed undersurface acts to overcome the force exerted by said spring and thus move said head away from its position sealingly closing said outlet means.

Claim 16

The invention of claim 13 wherein stop means are provided within said accumulator chamber to limit travel of said stem and wherein said means defining a passage comprise a collar.

Claim 17

The invention of claim 14 wherein said means defining an accumulator chamber comprise a generally cylindrical sleeve having a closed outer end and an open inner end, said inner end defining an accumulator outlet having an inner end abutment surface, said abutment surface contacting said collar such that said collar forms a closure for said accumulator outlet means.

Claim 18

The invention of claim 15 wherein said sleeve has filter means thereon which means cooperate with said case to filter impurities from the fuel after it enters the inlet means.

Claim 19

The invention of claim 16 wherein the filter means comprise a first and a second plurality of longitudinally extending grooves on the sleeve outer surface of said sleeve, said first plurality extending from said outer end to a point adjacent the inner end, said second plurality extending from said inner end to a point adjacent the outer end, such that fuel entering said inlet will flow from said first to said second plurality of grooves between said sleeve and said case and thence to said valve chamber and thereby filter impurities from the fuel.

Claim 20

The invention of claim 15 wherein said abutment surface is conical in shape and wherein said collar has a spherical face contacted by said abutment surface and wherein said stop means are provided with a passage to permit flow of fluid therethrough.

Claim 21

The invention of claim 11 wherein filter means are provided within the case whereby fuel entering through said inlet means will be filtered to remove impurities therefrom.