JPS5877161A - Device for trimming flow for fuel distributing valve - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to engine fuel systems, and more particularly, to a fuel system that provides an equal amount of fuel flow from a multiple outlet fuel distribution valve to each of a plurality of engine fuel injectors. Regarding.

Engine fuel systems with fuel distribution valve assemblies having a single fuel inlet and multiple fuel outlets are well known. Fuel is supplied from each of the outlets individually to the fuel injectors through separate fuel manifold conduits. The fuel injector has an injection port for injecting fuel into the variable volume cylinder or constant volume chamber engine combustor.

In order to achieve controlled fuel distribution in such fuel systems, conventional operations have been performed to measure the fuel flow versus fuel pressure characteristics of each component within the system. The fuel flow versus fuel pressure characteristics of each component are kept constant to allow system components to be interchanged with similar ones without affecting the control of the system's fuel flow distribution. Although it is desirable to maintain this within range, each element (component) of the system and its replacement may have slightly different fuel flow versus fuel pressure characteristics. In the past, it has been common to provide a trimming orifice at the inlet of each fuel injector as a means of calibrating the system to permit replacement of injector parts. The orifice is removable and can be adjusted in size to adjust the fuel flow versus fuel pressure characteristics from the inlet of the distribution valve to the tip injection port of each injector nozzle.

By using a trigon orifice that can be placed in the inlet of an injector, the fuel flow for all injectors in the system can be held to precise limits 1/C.

The same method has traditionally been used to adjust individual fuel injectors to maintain fuel flow within tight limits to allow for interchangeability of parts. In that case, the trigon orifice is located at the inlet end of the manifold to adjust the fuel flow versus fuel pressure characteristics of the manifold.

Due to dimensional changes within the system, the length and shape (bent portions, etc.) of each individual fuel manifold from its connection point with the outlet of the single distribution valve to its connection point with the inlet of the fuel injector may vary. In that case, it is practically difficult to maintain all manifolds with the same fuel flow versus fuel pressure characteristics. Therefore, in that case, in order to maintain manifold compatibility without disturbing fuel distribution throughout the system, fuel flow in a manifold of a given length and shape is maintained at precise limits by the use of truncation orifices. .

Preferably, the fuel distribution valves of the fuel system have identical fuel metering slots for distributing metered fuel to each manifold and injector of the system. Although such slots are relatively easy to manufacture,
To adjust valve imbalances such as errors in the length, diameter, shape, etc. of the internal passage of the valve caused by dimensional errors in the valve, and errors in the length, diameter, shape, etc. of the internal branch passage (manifold) of the valve. Requires some flow adjustment downstream of the metering section. Accurately testing fuel distribution from a distribution valve assembly requires flowing fuel through the entire system or similar device to account for leaks between parts of the system.

Fluctuations in fuel flow versus fuel pressure within the valve are currently accommodated by using replaceable trimming orifices similar to those used in conjunction with each manifold and each injector nozzle; Adjusting for such variations in fuel flow vs. fuel pressure characteristics becomes more difficult when fuel is being flowed throughout the system. This is because making such an adjustment to one of the internal valve passages will also affect the amount of fuel distributed through the other non-internal passages. Therefore, inspecting and adjusting the distribution valve is a lengthy and tedious operation that requires the system to be shut down, and each element of the system must be The trimming orifice must be reinstalled many times through trial and error.

It is an object of the present invention to provide an externally adjustable flow trimming adjustment means for adjusting fuel flow versus fuel pressure characteristics for each of a plurality of passages in a fuel distribution valve for an engine fuel system. That's true.

It is another object of the present invention to adjust the amount of fuel dispensed from the fuel distribution valve to a desired value without the need for removal from the fuel system or similar equipment and to control the overall system fuel flow through the valve. A fuel flow to fuel pressure-phasing flow trimming adjustment means is provided downstream of the fuel metering section in the fuel distribution valve and is externally adjustable without the need for shutdown. It is to provide.

Yet another object of the invention is to provide a flow trimming system of the type described above with means for making it possible to make adjustments to fuel flow versus fuel pressure in each of the valve passages while still allowing fuel to flow through the system. The purpose of this invention is to provide adjustment means.

Yet another object of the invention is to provide a flow trimming adjustment means of the above type with locking means for locking the adjustment means in an adjusted position for controlling the flow versus pressure characteristics in each valve passageway. It is to provide.

Another object of the invention is to provide a locking means which is externally removable for externally adjusting the flow trimming adjustment means and which provides a backup seal on the trimming adjustment means.

The flow distribution valve to which the present invention relates has a single inlet and a plurality of outlets, and includes flow metering means between the inlet and the outlet for metering fuel to each outlet. According to the invention, at each outlet of the valve, an internal bore intersects with a non-internal passage located downstream of the metering means, into which an externally threaded flow trimming plug is adjusted. Screw on freely. The plug has a nose positioned axially within the internal passageway to define a flow cross section for setting desired fuel flow versus fuel pressure characteristics. The exterior of the plug is provided with an annular skirt having a conical inner surface that connects to the waist of the plug. A seal for the inner hole is attached to the outer surface of the waist.

The inside of the waist includes flow trimming means providing a tool-receiving socket for receiving a tool for removing the plug from the bore or for adjusting the plug axially in the bore for adjustment of the flow cross section of the non-internal passage. After proper adjustment, the skirt is deformed to provide a wedge-shaped locking ring insertable into the skirt to sealingly engage the wall of the bore to form a secondary seal.

Values and other objects, features and advantages of the present invention will become more apparent from the following description taken in conjunction with the accompanying drawings.

Referring to FIG. 1, a fuel distribution valve 1o is shown having a single inlet 12 adapted to receive fuel from a suitable fuel control device 14. Referring to FIG. Valve 1° is September 1, 1981
Valve body 16 and liner 1 were manufactured by the method detailed in U.S. Patent Application No. 3011.719, filed on
A pressure-responsive valve body 16 is provided slidably mounted within the liner 18 for controlling fuel flow through metering holes 20, 22 respectively formed in the liner 18. Other details of valve 10 have been omitted to simplify the description of the invention, although details of the components and operation of valve 10 are described in the above-cited US patent application.

Whole system fuel R from inlet 12 (total fuel flow throughout the fuel system)
is metered by the sliding movement of the valve body 14.

That is, the sliding movement of the valve body 16 causes the holes 18 and 20 to overlap, thereby metering and distributing fuel to each of a plurality of outlets 24 spaced apart around a distribution head 26 formed in the valve body 28. do.

Fuel flow communication between each of the metering slots 20.22 and each outlet 24 is established through a lateral passageway 50 formed in the liner 18.
It has individual passages s2 aligned at 0. The horizontal passageway 52 communicates with the vertical bore 34 and side bores 36 formed in the dispensing head 24 . The side inner hole 36 has a cylindrical protrusion 58
The outer surface of the valve body 28 is penetrated at the outer surface of the valve body 28. There are several circumferentially spaced projections 58 formed around the dispensing head, each aligned with each outlet 24 .

Mounted within each tube [38 is a flow trimming assembly 4o and locking means 42 constructed in accordance with the present invention.

As mentioned above, differences in flow characteristics occur in the internal passage 20, 22, 30% 52 of the valve and the discharge port 24 due to the dimensional error of M-F. Flow trimming assembly 4G is located downstream of each metering element (20, 22, 30, 52) within the valve and serves to individually calibrate multiple flow paths within the valve. The fuel system includes a plurality of fuel 1 manifolds 44 connected to each of the outlets 24 downstream of the trimming assembly 40, with one end of the manifold 44 (only one shown in FIG. 1) connected to each of the exhaust ports 24. A removable adjustment orifice 46 is attached to the. Each fuel manifold 44 is connected to the inlet end of a fuel nozzle 48. A removable adjustment orifice 50 is mounted at the inlet end of each nozzle.

Fuel system components downstream from valve 10 can be preadjusted to achieve specific flow characteristics. However, after the fuel system is assembled, various imbalances may occur due to leakage between the internal passages of the valve 10, head fluctuations in the internal passages, dimensional changes, and the like.

Accordingly, the present invention provides a ki51 valve for making it possible to adjust the fuel flow characteristics versus fuel pressure characteristics of the fuel system downstream of the metering element constituted by the valve body 16 and the metering holes 20, 22 of the liner 18. It is contemplated that a trimming assembly 40 may be provided.

Each flow trimming assembly 4 as shown in FIG.
0 has a threaded peripheral surface 53 and an inner nose portion 54 at one end;
A plug 52 is provided with a skirt 56 at the other end.

The plug 52 is axially threaded into the threaded portion 55 of the bore 56 such that the nose 54 of the plug is defined by the intersection 11ss of the vertical bore 34 and the horizontal passageway 32 as viewed in FIG. The arrangement is such that a part of the flow path is closed. plug 52
The flow cross-sectional area of the flow path can be adjusted by adjusting the screw in the axial direction of the inner hole 36.

The waist 60 of the plug 52 is formed with an outer shoulder 62 for receiving an O-ring 64 that provides a partial seal to prevent leakage from the bore 36. On the inside of the waist part 60, there is a valve 1.
A tool receiving socket t6 is formed which can be accessed from the outside of the tool.

The socket 66 is a socket that receives a tool for adjusting the screwing of the plug 52 in the axial direction of the inner hole 36 .

If the position of the plug 52 is adjusted while the fuel continues to flow, and the desired adjustment of the fuel flow characteristics versus fuel pressure characteristics is obtained by adjusting the flow cross-sectional area of the intersection portion 5B, then it is appropriate to adjust the position of the plug 52. The information is displayed on a display device (not shown). This trimming is performed with the total fuel flow of the fuel system still entering through a single inlet 12 (FIG. 1). Modifying the flow cross-sectional area of one branch passage 32,34 will result in variations in each of the remaining branch passages;
If deviations from the desired flow characteristics of each branch passage occur, such deviations can be easily corrected by a flow string assembly 40' mounted within the bore 36 associated with the corresponding branch passage. can. This operation is performed with all fuel system components intact and with total fuel flow flowing through the system. Thus, adjustments to obtain the desired fuel flow versus fuel pressure characteristics can be made for each flow path by shutting down the fuel system, disassembling each element, and
There is no need for time consuming and cumbersome trial and error methods that require reconnection.

Once the fuel system has been adjusted to meet the desired distribution requirements, the plug is removed by engaging a wedge-shaped ring 70 having a conical inner surface 6 on the outer end of the plug 52. Lock it. surface 68 and ring 70
constitutes the locking means 42. When inserted into position as shown in FIG. 2, ring 70 exerts a radial force on plug 52 by a wedging action, causing skirt 56
is brought into pressure contact with the wall of the inner hole 36. Skirt 56 and inner hole 36
An interference fit with the wall locks the plug 52 in its adjusted position. Plug 52 has internal threads 71 for receiving a seating tool for press-fitting Su/Guar 0 into position.

When the plug 52 is positioned and locked, the ring 70 holds the outer surface 72 of the skirt 56 against the wall of the bore 36. The outer surface 72 has a plurality of axially spaced annular grooves 74 formed therein to form a secondary seal outwardly of the O-ring 64. The ring 70 has a threaded circumferential surface 75 having an inner diameter larger than the inner diameter of the threaded portion 71 into which the seating tool is inserted. What circumference surface 7 of this screw
5 is a ring 70 for changing the adjustment position of the plug 52;
is adapted to accept a tool for removal.

No.! Factors 1 to 4 show alternative embodiments of the invention.

In this embodiment, the valve body 76 of the flow distribution valve is provided with a single inlet passage 7B, which communicates with the interior of the valve body 80. Metering holes 82 and 84 are formed in the walls of the valve body 80 and the inner bore 86 of the valve body 760, respectively. The operation of this valve is described in the above-mentioned US patent application Ser. No. 300,719. Bore 82 , 84 is formed to extend laterally into the valve body from the outer surface of valve body 76 .
B, is located upstream of 88 and constitutes a metering element communicating with bore 88.88. Each bore 88 intersects a discharge passageway 90 leading to a discharge port 92 . Each outlet 92 is connected to a downstream fuel manifold and fuel nozzle of the type described in connection with previous embodiments.

In the embodiment of FIGS. 3-4, each bore 88 is fitted with a flow trimming assembly 94. In the embodiment of FIGS. Each assembly 94 includes an externally threaded plug 96 having a snout 98 adjustably positioned at the intersection 99 of passageway 90 and bore 88 to adjust the flow cross-sectional area through the intersection. Become. The outer flange head 102 of the plug 96 is press fit within the bore 88 . Head 102 defines an inner shoulder that carries an O-ring seal 104 for sealing bore 8B. A tool receiving socket 106 within the head 102 is for inserting a tool for axially threaded adjustment of the assembly 94 into the threaded portion 95 of the bore 8B. This makes it possible to set a desired fuel distribution, for example equal distribution from all the outlets, even if the flow path conditions of the fuel flow downstream of the outlets change.

5-6 illustrate a flow trimming assembly for trimming flow in a conventional single-metered edge flow distribution valve 110. This valve 110 includes a valve liner 118
It has a movable valve body 112 with a single metering lip 114 for metering the fuel flow in cooperation with a metering hole 116 drilled therein. Each hole 116 communicates with a drain tube 120 that fits within a side passageway 122 of a valve body 124 . Each outlet tube 120 has a side hole 124 for receiving a nose 128 of a flow stringing assembly 130. The embodiment of the FIGS. 1-2 assembly 150 is shown in FIG. It consists of elements similar to those of FIGS. 1-2, and elements that are similar to those of FIGS. 1-2 are designated with the same reference numerals and a prime.

The positioning and locking of the flow trimming assembly 150 of the embodiment of FIGS. 5-6 is similar to that of FIGS. 1-2.

By positioning the nose 128 within the linear fuel flow through the exhaust tube 120, the flow cross-sectional area is adjusted to adjust the fuel flow versus fuel pressure characteristics. Each exhaust pipe 120 is connected to a downstream fuel manifold and nozzle as shown in FIG.

In each of the above embodiments, the flow trimming assembly compensates for normal pressure drop variations in system pressure and also compensates for head variations caused by changes in the position of the valve body relative to the nozzle and fuel manifold and elevation positions. .

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a fuel system incorporating the present invention, 1111
．． 1. ,,,"",1 FIG. 2 is an enlarged partial cross-sectional view of the flow trimming adjustment means of the system of FIG. 1, and FIG. 5 is a flow control valve with flow trimming adjustment means according to another embodiment of the invention 4 is an enlarged sectional view of the flow trimming control means of the valve of FIG. 3; FIG. FIG. 6 is a partial cross-sectional view of a flow distribution valve with flow trimming adjustment means according to another embodiment of the invention; FIG. 6 is a cross-sectional view of the flow trimming adjustment means of the valve of FIG. 5; 10: Distribution valve 12: Inlet/24: Outlet 28: Valve body 56: Bore 40: Flow trimming assembly 52: Plug 54: Nose 56: Skirt 64: O-ring 55 FIG, 2 FIG, 5 FIG, 6

Claims (1)

Claims: 1) A fuel flow distribution system comprising a distribution valve having a valve body with a single inlet and a plurality of outlets each connected to a manifold leading to a fuel injector; A flow trimming device for regulating fuel flow at a valve body, comprising a plug mounted axially movably within a bore provided in the valve body, the neck plug being adapted to allow the plug to be inserted into the valve body. an outer end accessible from the outside of the dispensing valve for position adjustment within the bore, and sealing means for clamping said bore, depending on the position of the plug within said bore; The fuel flow cross-sectional area to each outlet can be varied, thereby keeping the entire fuel flow of the fuel flow distribution system flowing through the system and without the need to disassemble the cough system components. . A flow trimming device adapted to allow fuel 151S characteristics versus fuel pressure characteristics to be determined at each of said outlets. 2) the outer end includes a skirt portion and a locking member that engages the skirt portion and presses the skirt portion against the valve body to lock the plug in an axially adjusted position; 2. The flow trimming device of claim 1, further comprising: a locking member removable from the exterior of the predispensing valve. 3) the outer end has a skirt with a plurality of grooves on the outside, and the sealing means includes a primary O-ring seal mounted on the outer circumference of the plug and radially outwardly deflecting the skirt; 2. A flow trimming device as claimed in claim 1, further comprising means for pressing the inner bore against said bore to form a secondary seal. 4) Single inlet and manifold IcI each leading to a fuel injector! ! A flow trimming device for regulating fuel flow at each outlet in a fuel flow distribution system including a distribution valve having a valve body having a plurality of outlets connected to each other, the flow trimming device comprising: a flow trimming device disposed within the valve body; a plug axially movably mounted within the bore, the plug having an outer end accessible from outside the distribution valve for adjusting the position of the plug within the bore; , having sealing means for sealing the bore so as to vary the fuel flow cross-sectional area to each outlet depending on the position of the plug within the bore, thereby controlling the fuel flow distribution system. The fuel flow characteristics versus the fuel pressure characteristics can be adjusted at each of the outlets without requiring disassembly of any components of the cough system while keeping the entire fuel flow flowing through the system. A male thread is cut in a part of the shell plug, and a part of the inner hole is screwed with the male thread of the shell plug so that the plug can be screwed and adjusted in the axial direction within the inner hole. A flow trimming device characterized by an internal thread. 5) The outer end has a skirt portion and a lock that engages the skirt portion and presses the skirt portion against the valve body to lock the plug in an axially adjusted position. 5. The flow trimming device of claim 4, further comprising a member, the locking member being removable from the exterior of the distribution valve. 6) The outer end has a skirt with a plurality of grooves on the outside, and the sealing means includes a primary O-ring seal mounted on the outer circumference of the plug and radially outwardly deflecting the skirt. 5. A flow trimming device as claimed in claim 4, including means for pressing the lumen against the wall of the bore to form a secondary seal.