A fuel distributor, tool and method for facilitated disassembly of fuel rail assemblies

Abstract

The invention proposes a tool (5) and an improved fuel distributor (1) for use in separation of a fuel rail assembly (100) from a combustion engine. The tool (5) comprises a base (53) with one or more through holes (51) for a passage of a threaded portion (41) of a threaded bolt (40) that has a head portion (42) having a diameter greater than a diameter of the respective through holes (51). The tool (5) is arranged for engaging with a fuel rail assembly (100), by passing the threaded portion (41) of the threaded bolt (40) through a respective through hole (51) to extend from a first side of base (53), so that the head portion (42) is retained at a second side of the base (53) and the threaded portion (41) is engaged with fuel distributor (1) the by turning the threaded bolt (40) in the threaded bore (21).

Description

[0001] SPECIFICATION

[0002] A FUEL DISTRIBUTOR, TOOL AND METHOD FOR FACILITATED DISASSEMBLY OF FUEL RAIL ASSEMBLIES

[0003] Technical Field of the Invention

[0004] The present disclosure relates to a fuel distributor for a fuel charge assembly, a tool and a method for separating such fuel charge assembly from a combustion engine.

[0005] Background of the Disclosure

[0006] Fuel rail assemblies or fuel charge assemblies, in particular for common rail systems, are known in the art. A fuel rail assembly generally includes a group of fuel injectors for provision of fuel through nozzles thereon, into respective combustion chambers of an internal combustion engine. Each of the fuel injectors is connected to a fuel distributor over respective injector cups at an opposite end of the fuel injector with regard to the nozzles. CN 212406922 U and WO 2012 / 150074 A1 disclose exemplary fuel distributors for use in fuel rail assemblies.

[0007] The injector cups connect each respective fuel injector to the fuel distributor. The injector cups can be formed on the fuel distributor, e.g., integral therewith. A fuel distributor is provided with a connection bore for allowing fluid flow coming from a fuel chamber of the fuel distributor to the fuel injectors via inner volume of the respective injector cups.

[0008] Attachment of the fuel injectors to respective injector cups can be achieved using fixing members such as U-clips, for axial stabilization of the fuel injectors relative to the injector cups. The fuel rail assembly can further include retaining arms for axially biasing the fuel injectors away from the respective injector cups. A retaining arm can be considered as a damper to axial forces that emerge during combustion in a combustion chamber and push the fuel injector away from the combustion chamber. So, retaining arms reinforce sealing between the fuel injectors and respective combustion chambers. TR 2016 / 19492 discloses an exemplary retaining arm for use in such fuel rail assemblies.

[0009] Hence, a fuel rail assembly can be considered as a combined structure that includes a group of fuel injectors that are attached to a fuel distributor over respective injector cups via fixing members and that are provided with respective retaining arms. Engagement between such fuel rail assembly and a respective group of combustion chambers involves the introduction of nozzle tips of the fuel injectors through open ends of respective combustion chambers. Such introduction is generally performed in a direction that extends along the gravity vector or that has a component in the gravitational direction when the engine is in use. Then, the fuel rail assembly is secured for stabilizing the same from moving relative to the combustion chambers along main central axes thereof. Because of the component in the gravitational direction, such fuel rail assembly can also be referred to as a suspended fuel rail assembly.

[0010] Maintenance and repair of a component of the fuel rail assembly requires the disassembly of the same. Such disassembly can involve removal of one or more of fixing members, so that one or more corresponding fuel injectors can be separated from respective injector cups.

[0011] The removal of a fixing member can require translation of the same in a radial direction with regard to a main central axis of the respective fuel injector, until the fixing member is completely separated from one or both of the injector cup and fuel injector. In some cases, the engine architecture does not allow such separation, because there is no sufficient room around the fixing member available for such radial translation of the same.

[0012] It is considered desirable to develop a solution to this problem.

[0013] Brief Description of the Disclosure

[0014] An object of the disclosure is to provide a fuel distributor for fuel rail assemblies, which is easy to separate from a respective engine. Another object of the present disclosure is to provide a fuel distributor that allows an easy separation of fuel injectors from respective injector cups, even in the case of space limitations around a fixing member that holds the fuel injector and injector cup together. These objects are achieved by means of the respective sets of features that constitute the appended independent claims.

[0015] The present invention proposes a tool for use in separating a fuel rail assembly from a combustion engine. The tool comprises a base provided with one or more through holes for a passage of a threaded portion of a threaded bolt. The threaded bolt has a head portion with a diameter that is greater than a diameter of the respective through holes. The tool is arranged for engaging with a fuel rail assembly, by passing the threaded portion of the bolt through a respective through hole to extend from a first side of the base, so that the head portion is retained at a second side of the base that is opposite to the first side; and then aligning and engaging threaded portion with a threaded bore on a fuel distributor of the fuel rail assembly by turning the bolt.

[0016] Thus, the engagement between two or more threaded bolts with corresponding threaded bores reduces the degree of freedom in terms of orientation when pulling the fuel distributer away from an engine. This increases the degree of certainty in operation and thus further facilitates the task of an operator when removing the fuel rail assembly. Thus, the possibility of mechanical damage of all the parts of the fuel rail assembly is reduced and the service life is extended. Furthermore, this reduces the load on threaded bores and threaded bolts; thereby enhancing service life of the tool and fuel distributor.

[0017] In a possible embodiment of the invention, the tool can comprise two or more of the through holes for aligning and engaging respective two or more of the bolts with respective two or more threaded bores on the fuel distributor.

[0018] In a possible embodiment of the invention, the tool can comprise one or more handles, such that the tool can be manually pulled at the handle in a first direction from the first side towards the second side.

[0019] In a possible embodiment of the invention, the one or more handles can be provided at the second side of the base.

[0020] The present disclosure further proposes a fuel distributor for a fuel rail assembly for combustion engines. The fuel distributor comprises one or more injector cups with respective main central axes. Each injector cup is arranged for engaging with a respective fuel injector with a nozzle tip by receiving a first end of the fuel injector opposite to the nozzle tip in a first direction from the nozzle tip towards said first end, through an opening of the injector cup, such that the fuel injector extends along the respective main central axis when engaged to the injector cup.

[0021] The fuel distributor is provided with one or more threaded bores for engaging with respective one or more threaded bolts of a tool for use in separating the fuel rail assembly from a combustion engine. Although the fuel distributor and tool are individual entities that are separately proposed in the present disclosure, the tool is as it is defined above. Hence, it is presumed that the tool comprises a base provided with one or more through holes for a passage of a threaded portion of the threaded bolt, that has a head portion having a diameter which can be inherently considered to be greater than a diameter of the respective through holes. The tool is arranged for engaging with the fuel rail assembly, by passing the threaded portion of the bolt through a respective through hole to extend from a first side of the base, so that the head portion is retained at a second side of the base that is opposite to the first side, and then aligning and engaging threaded portion with a respective one of the one or more threaded bores by turning the threaded bolt.

[0022] In a possible embodiment, the one or more threaded bores can be coaxially provided on the respective one or more injector cups.

[0023] In a possible embodiment, the one or more threaded bores can be provided on one or more mounting brackets of the fuel distributor.

[0024] In a possible embodiment, the fuel distributor can comprise two or more of the threaded bores.

[0025] The present disclosure further proposes a method for separating a fuel rail assembly from a combustion engine to which a fuel distributor of the fuel rail assembly is attached. For the method it is presumed that the fuel distributor includes one or more injector cups with respective main central axes to coaxially receiving in a first direction and engaging to first ends of respective one or more fuel injectors opposite to nozzle tips of the respective fuel injectors. The method comprises the following steps: step-a) locating one or more threaded bores on the fuel distributor; aligning one or more through holes provided on a base of a tool with the one or more threaded bore; step-b) passing threaded portions of one or more threaded bolts through the through holes, so that head portions of the threaded bolts remain at an opposite side of the base with regard to the threaded bore; step-c) engaging the threaded portions of the one or more threaded bolts with the respective threaded bores; such that the base is sandwiched inbetween the fuel distributor and the head portions of the threaded bolts; and step-d) pulling the base in a first direction that extends from the one or more threaded bores towards the head portions of the respective threaded bolts. In a possible version of the method, the step-a can comprise locating the one or more threaded bores on one or more injector cups on the fuel distributor of the fuel rail assembly, at the injector cups respective one or more fuel injectors being attached at a first end of the fuel injectors that is opposite to respective nozzle tips of the fuel injectors regarding respective main central axes of the fuel injectors.

[0026] In a possible version of the method, the step-c can comprise introduction of the threaded portions of the one or more threaded bolts into the respective one or more threaded bores along the main central axes, such that a main axis of the one or more threaded bolts overlap with the main central axes.

[0027] Therefore, this method minimizes or even eliminates the forces that can apply onto the fuel injector in directions that are transverse to the main central axis, at separation of the fuel rail assembly with the fuel distributor, from an engine block or body. Thus, the possibility of mechanical damage of all the parts of the fuel rail assembly is reduced and the service life is extended.

[0028] Brief Description of the Figures

[0029] Fig.1 is a schematical perspective view of an exemplary embodiment of the tool according to the present disclosure.

[0030] Fig.2 is a schematical exploded front view of an exemplary fuel injector assembly in which an exemplary embodiment of the fuel distributor according to the present disclosure is employed, aligned with an exemplary embodiment of the tool according to the present disclosure.

[0031] Detailed Description of the Invention

[0032] The present disclosure proposes a fuel distributor (1) for a fuel rail assembly (100) with fuel injectors (10), that can be suitable for being employed in common rail systems. The present disclosure further proposes a tool (5) for separation of a fuel rail assembly (100) that is provided with the proposed fuel distributor (1), from a combustion engine. The present disclosure further proposes a method for separating a fuel rail assembly (100) that is provided with the proposed fuel distributor (1), using the proposed tool (5).

[0033] Engagement between such fuel rail assembly (100) and a respective group of combustion chambers involves the introduction of nozzle tips (11) of the fuel injectors (10) through open ends of respective combustion chambers. Such introduction is generally performed in a direction that extends along the gravity vector (g) or that has a component in the gravitational direction when the engine is in use. Then, the fuel rail assembly (100) is secured for stabilizing the same from moving relative to the combustion chambers along main central axes (A) thereof. Because of the component in the gravitational direction, such fuel rail assembly (100) can also be referred to as a suspended fuel rail assembly (100).

[0034] Fig.1 is a schematical perspective view of an exemplary embodiment of the tool (5) according to the present disclosure.

[0035] An exploded side view of an exemplary fuel rail assembly (100) that is provided with a possible embodiment of the proposed fuel distributor (1) embodiment schematically depicted in Fig.2. Fig.2 represents an instance where one or more threaded bolts (40) of the tool (5) are aligned for engagement with one or more threaded bores (21) on the fuel distributor (1).

[0036] The tool (5) that is proposed herein is arranged to be suitable for use in separating a fuel rail assembly (100) from a combustion engine. Referring to Fig.1 , the tool (5) comprises a base (53) provided with one or more through holes (51) for a passage of a threaded portion (41) of a threaded bolt (40). The threaded bolt (40) can be considered to inherently have a head portion (42) with a diameter that is greater than a diameter of the respective through holes (51).

[0037] Referring back to Fig.1 in conjunction with Fig.2, the tool (5) is arranged for engaging with a fuel rail assembly (100), by passing the threaded portion (41) of the threaded bolt (40) through a respective through hole (51) to extend from a first side of the base (53), so that the head portion (42) is retained at a second side of the base (53) that is opposite to the first side; and then aligning and engaging threaded portion (41) with a threaded bore (21) on a fuel distributor (1) of the fuel rail assembly (100) by turning the threaded bolt (40). The tool (5) thus provides a facilitated separation of a fuel rail assembly (100) which is equipped with an accordingly designed fuel distributor (1), which is described in detail in the present specification.

[0038] A possible embodiment of the tool (5) can comprise two or more of the through holes (51) for aligning and engaging respective two or more of the threaded bolts (40) with respective two or more threaded bores (21) on the fuel distributor (1). The engagement between two or more threaded bolts (40) with corresponding threaded bores (21) reduces the degree of freedom in terms of orientation when pulling the fuel distributer (1) away from an engine. This increases the degree of certainty in operation and thus further facilitates the task of an operator when removing the fuel rail assembly (100). Furthermore, this reduces the load on threaded bores (21) and threaded bolts (40); thereby enhancing service life of the tool (5) and fuel distributor (1).

[0039] The tool (5) can comprise one or more handles (52), such that the tool (5) can be manually pulled at the handle (52) in a first direction from the first side towards the second side. The presence of such one or more handles (52) facilitates the work and provides an enhanced comfort to an operator or technician.

[0040] As exemplified in Fig.1 , the one or more handles (52) can be provided at the second side of the base (53). So, the extent of required space around the tool (5) is reduced and the working space is rendered more compact.

[0041] Referring back to Fig.2, in accordance with the discussions above, the present disclosure further proposes a fuel distributor (1) for a fuel rail assembly (100) for combustion engines. The fuel distributor (1) comprises one or more injector cups (2) with respective main central axes (A). Each injector cup (2) is arranged for engaging with a respective fuel injector (10) with a nozzle tip (11) by receiving a first end (15) of the fuel injector (10) opposite to the nozzle tip (11) in a first direction (z) from the nozzle tip (11) towards said first end (15), through an opening (20) of the injector cup (2), such that the fuel injector (10) extends along the respective main central axis (A) when engaged to the injector cup (2).

[0042] Attachment of the fuel injectors (10) to respective injector cups (2) can be achieved using fixing members (3) such as U-clips, for axial stabilization of the fuel injectors (10) relative to the injector cups (2). The fuel rail assembly (100) can further comprise retaining arms (6) for axially biasing the fuel injectors (10) away from the respective injector cups (2).

[0043] The fuel distributor (1) is provided with one or more threaded bores (21) for engaging with respective one or more threaded bolts (40) of a tool (5) for use in separating the fuel rail assembly (100) from a combustion engine. Although the fuel distributor (1) and tool (5) are individual entities that are separately proposed in the present disclosure, the tool (5) is as it is defined above. Hence, it is presumed that the tool (5) comprises a base (53) provided with one or more through holes (51) for a passage of a threaded portion (41) of the threaded bolt (40), that has a head portion (42) having a diameter which can be inherently considered to be greater than a diameter of the respective through holes (51). The tool (5) is arranged for engaging with the fuel rail assembly (100), by passing the threaded portion (41) of the threaded bolt (40) through a respective through hole (51) to extend from a first side of the base (53), so that the head portion (42) is retained at a second side of the base (53) that is opposite to the first side, and then aligning and engaging threaded portion (41) with a respective one of the one or more threaded bores (21) by turning the threaded bolt (40).

[0044] The one or more threaded bores (21) can be coaxially provided on the respective one or more injector cups (2). This reduces the occurrence of forces on the threaded bores (21) and threaded bolts (40) in directions transverse to the main central axis (A). So, not only the threaded bores (21) and threaded bolts (40), but also the injector cups (2) and fuel injectors (10) are protected from unnecessary mechanical strains.

[0045] Furthermore or alternatively, one or more mounting brackets (22) of the fuel distributor (1) can be provided with one or more of the threaded bores (21), which is not shown in the figures. The tool (5) can be also adapted accordingly, with through holes (51) arranged for alignment to such threaded bores (21) that can be provided on the one or more mounting brackets (22). These enables engagement between the tool (5) and fuel distributor (1) at one or more points that are out of a line that can be defined by one or more threaded bores (21) that can be coaxially provided on an array of injector cups (2). So, the degree of freedom that is discussed above can be even further reduced, thereby maximizing the certainty in direction of translational movement when separating a corresponding fuel rail assembly (100) from a combustion engine. As a result, the operation is further facilitated. On top of it, mechanical strains that apply on the threaded bores (21), threaded bolts (40), injector cups (2) and fuel injectors (10) are minimized; and the service life of the fuel distributor (1) and of the tool (5) are inherently maximized. Accordingly, the fuel distributor (1) can comprise two or more of the threaded bores (21).

[0046] In line with the discussions above, the present disclosure further proposes a method for separating a fuel rail assembly (100) from a combustion engine to which a fuel distributor (1) of the fuel rail assembly (100) is attached. For the method it is presumed that the fuel distributor (1) includes one or more injector cups (2) with respective main central axes (A) to coaxially receiving in a first direction and engaging to first ends of respective one or more fuel injectors (10) opposite to nozzle tips (11) of the respective fuel injectors (10). Referring back to Fig.2; the method comprises the following steps: step-a) locating one or more threaded bores (21) on the fuel distributor (1); aligning one or more through holes (51) provided on a base (53) of a tool (5) with the one or more threaded bores (21); step-b) passing threaded portions (41) of one or more threaded bolts (40) through the through holes (51), so that head portions (42) of the threaded bolts (40) remain at an opposite side of the base (53) with regard to the threaded bores (21); step-c) engaging the threaded portions (41) of the one or more threaded bolts (40) with the respective threaded bores (21); such that the base (53) is sandwiched in-between the fuel distributor (1) and the head portions (42) of the threaded bolts (40); and step-d) pulling the base (53) in a first direction that extends from the one or more threaded bores (21) towards the head portions (42) of the respective threaded bolts (40).

[0047] The step-a can comprise locating the one or more threaded bores (21) on one or more injector cups (2) on the fuel distributor (1) of the fuel rail assembly (100), at the injector cups (2) respective one or more fuel injectors (10) being attached at a first end of the fuel injectors (10) that is opposite to respective nozzle tips (11) of the fuel injectors (10) with regard to respective main central axes (A) of the fuel injectors (10).

[0048] The step-c can comprise introduction of the threaded portions (41) of the one or more threaded bolts (40) into the respective one or more threaded bores (21) along the main central axes (A), such that a main axis of the one or more threaded bolts (40) overlap with the main central axes (A).

[0049] After separating the fuel rail assembly (100), fixing members (3) such as U-clips that fix fuel injectors (10) to respective injector cups (2) can be removed by radially pulling the fixing members (3) with regard to a main central axis (A) of the injector cup (2). So, the fuel injectors (10) can be easily separated from respective injector cups (2), notwithstanding whether there is sufficient radial space around the fixing member (3) is available for removal of the same when the fuel rail assembly (100) is attached to an engine body. Hence, the tool (5), fuel distributor (1) and method proposed herein eliminate architectural structure-based difficulties in separation of a fuel rail assembly (100) from an engine body. Reference list:

[0050] 1 fuel distributor

[0051] 2 injector cup

[0052] 20 opening

[0053] 21 threaded bore

[0054] 22 mounting bracket

[0055] 3 fixing member

[0056] 40 threaded bolt

[0057] 41 threaded portion

[0058] 42 head portion

[0059] 5 tool

[0060] 51 through hole

[0061] 52 handle

[0062] 53 base

[0063] 6 retaining arm

[0064] 10 fuel injector

[0065] 11 nozzle tip

[0066] 15 first end

[0067] 100 fuel rail assembly

[0068] A axis g gravity vector z first direction

Claims

CLAIMS1. A tool (5) for use in separating a fuel rail assembly (100) from a combustion engine; wherein the tool (5) is characterized by; comprising a base (53) provided with one or more through holes (51) for a passage of a threaded portion (41) of a threaded bolt (40) that has a head portion (42) having a diameter that is greater than a diameter of the respective through holes (51) and; the tool (5) is arranged for engaging with a fuel rail assembly (100), by passing the threaded portion (41) of the threaded bolt (40) through a respective through hole (51) to extend from a first side of the base (53), so that the head portion (42) is retained at a second side of the base (53) that is opposite to the first side, and then aligning and engaging threaded portion (41) with a threaded bore (21) on a fuel distributor (1) of the fuel rail assembly (100) by turning the threaded bolt (40).

2. The tool (5) according to claim 1 , comprising two or more of the through holes (51) for aligning and engaging respective two or more of the threaded bolts (40) with respective two or more threaded bores (21) on the fuel distributor (1).

3. The tool (5) according to anyone of claims 1 or 2, comprising one or more handles (52), such that the tool (5) can be manually pulled at the handle (52) in a first direction from the first side towards the second side.

4. The tool (5) according to claim 3; wherein the one or more handles (52) are provided at the second side of the base (53).

5. A fuel distributor (1) for a fuel rail assembly (100) for combustion engines, the fuel distributor (1) comprising one or more injector cups (2) with respective main central axes (A); each injector cup (2) is arranged for engaging with a respective fuel injector (10) with a nozzle tip (11) by receiving a first end (15) of the fuel injector (10) opposite to the nozzle tip (11) in a first direction (z) from the nozzle tip (11) towards said first end (15), through an opening (20) of the injector cup (2), such that the fuel injector (10) extends along the respective main central axis (A) when engaged to the injector cup (2); characterized in that, the fuel distributor (1) is provided with one or more threaded bores (21) for engaging with respective one or more threaded bolts (40) of a tool (5) for use in separating the fuel rail assembly (100) from a combustion engine; wherein the tool(5) comprises a base (53) provided with one or more through holes (51) for a passage of a threaded portion (41) of the threaded bolt (40) that has a head portion (42) having a diameter that is greater than a diameter of the respective through holes (51); the tool (5) being arranged for engaging with the fuel rail assembly (100), by passing the threaded portion (41) of the threaded bolt (40) through a respective through hole (51) to extend from a first side of the base (53), so that the head portion (42) is retained at a second side of the base (53) that is opposite to the first side, and then aligning and engaging threaded portion (41) with a respective one of the one or more threaded bores (21) by turning the threaded bolt (40).

6. The fuel distributor (1) according to claim 5; wherein the one or more threaded bores (21) are coaxially provided on the respective one or more injector cups (2).

7. The fuel distributor (1) according to claim 5; wherein the one or more threaded bores (21) are provided on one or more mounting brackets (22) of the fuel distributor (1).

8. The fuel distributor (1) according to anyone of claims 5 to 7, comprising two or more of the threaded bores (21).

9. A method for separating a fuel rail assembly (100) from a combustion engine to which a fuel distributor (1) of the fuel rail assembly (100) is attached, wherein the fuel distributor (1) includes one or more injector cups (2) with respective main central axes (A) to coaxially receiving in a first direction and engaging to first ends of respective one or more fuel injectors (10) opposite to nozzle tips (11) of the respective fuel injectors (10); wherein the method comprises the following steps: step-a) locating one or more threaded bores (21) on the fuel distributor (1); aligning one or more through holes (51) provided on a base (53) of a tool (5) with the one or more threaded bores (21); step-b) passing threaded portions (41) of one or more threaded bolts (40) through the through holes (51), so that head portions (42) of the threaded bolts (40) remain at an opposite side of the base (53) with regard to the threaded bores (21); step-c) engaging the threaded portions (41) of the one or more threaded bolts(40) with the respective threaded bores (21); such that the base (53) issandwiched in-between the fuel distributor (1) and the head portions (42) of the threaded bolts (40); and step-d) pulling the base (53) in a first direction that extends from the one or more threaded bores (21) towards the head portions (42) of the respective threaded bolts (40).

10. The method according to claim 9; wherein the step-a comprises: locating the one or more threaded bores (21) on one or more injector cups (2) on the fuel distributor (1) of the fuel rail assembly (100), at the injector cups (2) respective one or more fuel injectors (10) being attached at a first end of the fuel injectors (10) that is opposite to respective nozzle tips (11) of the fuel injectors (10) with regard to respective main central axes (A) of the fuel injectors (10).

11. The method according to anyone of claims 9 or 10; wherein the step-c comprises introduction of the threaded portions (41) of the one or more threaded bolts (40) into the respective one or more threaded bores (21) along the main central axes (A), such that a main axis of the one or more threaded bolts (40) overlap with the main central axes (A).

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