Injector sleeve with internal groove

Abstract

An injector sleeve for a cylinder head may include a lower portion, a middle portion, and an upper portion. The upper portion may have a maximum thickness along at least a portion of its length and have a groove on an inner surface of the injector sleeve. The groove may have an upper flat surface perpendicular to the longitudinal axis of the injector sleeve. A related method of removing an injector sleeve from a cylinder head may include inserting a removal tool into an injector sleeve within the cylinder head by a predetermined depth, engaging a surface of the removal tool with an upper flat surface of a groove on an inner surface of an upper portion of the injector sleeve, and pulling the removal tool outwardly from the cylinder head, thereby removing the injector sleeve from the cylinder head.

Description

Technical Field

[0001] The present invention generally relates to an injector sleeve for an injector inserted into a cylinder head of an engine block, and more particularly to an injector sleeve having an internal groove, and a related method of removing the injector sleeve from the cylinder head. Background Art

[0002] Internal combustion engines use fuel injectors to supply fuel to cylinders of the engine block. To facilitate placement and securing of the fuel injector within an opening in a cylinder head of the engine block, an injector sleeve is press fit into the opening in the cylinder head and the fuel injector is then pressed into the injector sleeve. The shape of the injector sleeve, including the location and number of any grooves or other indentations, is limited by the need for a secure fit between the injector sleeve and the opening in the cylinder head and the need for a secure fit between the injector sleeve and the fuel injector. Removal of the injector sleeve for replacement as part of routine engine maintenance may require insertion of a removal tool, such as an injector sleeve puller. The injector sleeve puller is inserted into the inner bore of the injector sleeve and rotated to cut threads into the inner surface of the injector sleeve, or, if the injector sleeve puller has one or more expansion members, these members expand outwardly and bite into the inner surface of the injector sleeve to form and engage threads on the inner surface of the injector sleeve and provide leverage when the injector sleeve puller and injector sleeve are pulled out of the cylinder head.

[0003] Chinese Utility Model Publication No. 203214217U ('217 Publication) describes an injection tool for removing a fuel injector boot from a cylinder head of a diesel engine. The injection tool has a pawl expander that expands a pawl into the inner wall of the fuel injector boot, forming a groove therein. The crankshaft of the engine is rotated by human power to cause the piston to rise, pushing the injection rod of the injection tool upward, thereby pushing the injection tool and the fuel injector boot upward and pushing it out of the mounting hole of the cylinder head. Therefore, the injection tool of the '217 Publication is therefore a special tool for removing injector sleeves, and is designed to be deeply inserted into the fuel injector boot during the removal process so that the injector rod of the injection tool is exposed to the thrust of the piston in the engine cylinder.

[0004] However, there is a need for an improved injector sleeve that can be removed with a standard removal tool. The injector sleeve and associated method for removing an injector sleeve of the present invention may solve one or more of the above problems and / or other problems in the art. However, the scope of the present invention is defined by the appended claims and not by the ability to solve any specific problem. Summary of the invention

[0005] In one aspect, an injector sleeve for a cylinder head may include a lower portion, a middle portion disposed above the lower portion, and an upper portion disposed above the middle portion, the upper portion having a maximum thickness along at least a portion of its length and having a groove on an inner surface of the injector sleeve, the groove having an upper flat surface perpendicular to a longitudinal axis of the injector sleeve.

[0006] In another aspect, an injector sleeve for a cylinder head may include a lower portion, a middle portion disposed above the lower portion, and an upper portion disposed above the middle portion, the upper portion having a maximum thickness along at least a portion of its length and having a groove on an inner surface of the injector sleeve, the groove having an upper flat surface perpendicular to a longitudinal axis of the injector sleeve, a depth of the upper flat surface of the groove being about 1 mm to about 2.5 mm, and a distance between an upper end of the upper portion and the upper flat surface of the groove being about 18 mm or less, wherein the injector sleeve is configured for use with a common rail fuel injector.

[0007] In yet another aspect, a method for removing an injector sleeve from a cylinder head may include inserting a removal tool into the injector sleeve in the cylinder head to a predetermined depth of at least about 10 mm; engaging a surface of the removal tool with an upper flat surface of a groove on an inner surface of an upper portion of the injector sleeve; and pulling the removal tool outward from the cylinder head, thereby removing the injector sleeve from the cylinder head. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 A cross-sectional view of a portion of an engine according to the present invention is shown, the engine comprising an engine block, a cylinder head, a fuel injector and an injector sleeve.

[0009] Figure 2 Shows Figure 1 A cross-sectional view of the injector sleeve is shown.

[0010] Figure 3 Shows Figure 1 and 2 Detailed cross-sectional view of a portion of a groove of an injector sleeve shown in FIG.

[0011] Figure 4 It shows that according to the present invention Figures 1 to 3 A partial cross-sectional view of the removal tool and injector sleeve is shown.

[0012] Figure 5A , Figure 5B and Figure 5C Another removal tool and Figures 1 to 3 A partial cross-sectional view of an injector sleeve is shown during removal.

[0013] Figure 6A flow chart of a method according to the invention for removing an injector sleeve is shown. DETAILED DESCRIPTION

[0014] The foregoing general description and the following detailed description are merely exemplary and illustrative and do not limit the claimed features. As used herein, the terms "include," "comprising," "having," "containing," or other variations thereof are intended to encompass non-exclusive inclusions, such that a process, method, article, or apparatus comprising a series of elements includes not only these elements, but may also include other elements not expressly listed or inherent to such process, method, article, or apparatus. In addition, in the present invention, relative terms (e.g., "about," "usually," "substantially," and "approximately," etc.) are used to indicate possible variations of ±10% in the stated values.

[0015] Figure 1 A cross-sectional view of a portion of an engine 100 is shown, including an engine block 105, a cylinder 110, a cylinder head 115, a fuel injector (or simply injector) 120, and an injector sleeve 125. The cylinder head 115 is mounted on the engine block 105 to form a combustion chamber 130. An intake manifold 135 and an exhaust manifold 140 may be mounted to the cylinder head 115 to form an intake passage 145 and an exhaust passage 150, respectively. An intake valve 155 is disposed between the intake passage 145 and the combustion chamber 130, and an exhaust valve 160 is disposed between the exhaust passage 150 and the combustion chamber 130. The injector 120 and the injector sleeve 125 are shown as being positioned within a mounting hole 165 of the cylinder head 115. As shown in FIG. Figure 1 As shown, the injector 120 includes an injector tip 170 that protrudes slightly below a surface 175 of the cylinder head and into the combustion chamber 130 .

[0016] The injector 120 extends along the longitudinal axis AA and has an upper end 180 and a lower end 185 adapted to be inserted into the injector sleeve 125. The injector sleeve 125 also extends along the longitudinal axis AA and may be a substantially cylindrical member having an open upper end 190 and a relatively narrower lower end 195 opposite the upper end 190. The injector tip 170 may be positioned within the injector sleeve 125 such that a portion of the injector tip 170 protrudes from the lower end 195 of the injector sleeve 125. The injector 120 may be press fit into the lower end 195 of the injector sleeve 125.

[0017] Figure 2 Shows Figure 1A cross-sectional view of the injector sleeve 125 is shown. The injector sleeve 125 is substantially cylindrical and includes, in order from the upper end 190 to the lower end 195, an upper portion 200, an upper tapered portion 205, a middle portion 210, a lower tapered portion 215, and a lower portion 220. The outer and inner surfaces of the middle portion 210 and the lower portion 220 of the sleeve may be non-inclined and devoid of any grooves or notches. As the names indicate, the upper tapered portion 205 and the lower tapered portion 215 are tapered so as to provide a gradual transition between the upper portion 200 and the middle portion 210 and between the middle portion 210 and the lower portion 220, respectively. One or both of the inner and outer surfaces of the upper tapered portion 205 and the lower tapered portion 215 may extend at an angle or be inclined relative to the longitudinal axis AA. Figure 2 In the illustrated embodiment, the upper tapered portion 205 may have an angled outer surface 225 and a non-angled inner surface 230 , while the lower tapered portion 215 may have an angled outer surface 235 and an angled inner surface 240 .

[0018] The upper end 190 has an upper end opening 245, which may have a tapered edge 250. For example, the upper end opening 245 may have a minimum diameter D 上-最小 and maximum diameter D 上-最大 ,like Figure 2 As shown. Minimum diameter D 上-最小 It can be about 22mm±5mm, and the maximum diameter D 上-最大 It can be about 25 mm ± 5 mm. The lower end 195 has a diameter D 下 The lower end opening 255. For example, D 下 It can be about 17mm±5mm.

[0019] The upper portion 200 may have a length L of the upper portion 200. 上 has a maximum thickness (or maximum sleeve thickness) T on at least a portion of 套筒-最大 , while the middle portion 210, the lower tapered portion 215 and / or the lower portion 220 may have a minimum thickness (or minimum sleeve thickness) T 套筒-最小 The upper portion 200 may also include one or more annular outer or external grooves 260 on the outer surface 265 of the injector sleeve 125. Figure 2 In the illustrated embodiment, the injector sleeve 125 includes two outer grooves 260. The outer grooves 260 may be adapted to receive the sealing ring 315 so that a tight seal is formed between the cylinder head 115 and the injector sleeve 125 when the injector sleeve 125 is inserted into the mounting hole 165 of the cylinder head 115.

[0020] The upper portion 200 may also have an inner groove 270 on the inner surface 275 of the injector sleeve 125. The inner groove 270 may have an upper flat surface 280, such as Figure 3As shown, it is perpendicular or approximately perpendicular to the longitudinal axis AA. The internal groove 270 may be the only groove on the inner surface 275 of the entire injector sleeve 125. In other words, the inner surface 275 of the injector sleeve 125 may not have any other grooves except the internal groove 270. The internal groove 270 is provided in the portion of the injector sleeve 125 having the largest thickness, here the upper portion 200, so that the injector sleeve 125 can withstand the forces acting on the injector sleeve 125 during the removal process. The internal groove 270 may extend 360° around the inner surface 275 of the injector sleeve 125. That is, the internal groove 270 may be an annular groove.

[0021] The depth D of the inner groove 270 is 凹槽 (or inner groove depth), also defined by the depth of upper planar surface 280, can be selected based on the size of a portion of a standard removal tool commonly used to remove injector sleeves. 凹槽 It can also be less than or equal to the minimum sleeve thickness T 套筒-最小 For example, the inner groove depth D 凹槽 It can be about 1 mm. In addition, the inner groove depth D 凹槽 It can be up to about 2.5 mm. The total length L of the injector sleeve 125 套筒 (or ejector sleeve length) may be about 67 mm ± 10 mm, and the length L of the upper portion 200 上 (or upper length) may be from about 17 mm to about 25 mm. Injector sleeve length L 套筒 The distance Δ between the inner groove 270 and the upper end 190 of the injector sleeve 125 may be determined based on the size of the cylinder head 115 in order to maintain the cooling performance of the cylinder head 115. 凹槽 In one embodiment, the distance Δ 凹槽 It can be between about 10 mm and about 18 mm. In one specific example, the distance Δ 凹槽 It can be about 15 mm. In addition, the length L of the inner groove 270 凹槽 (or inner groove length) may be in the range of about 2 mm to about 4 mm, and in particular, for example, may be about 2.25 mm. The dimensions of the injector sleeve 125 may be selected such that the injector sleeve may be used with a common rail fuel injector.

[0022] Figure 3 Shows Figure 1 and 2 Detailed cross-sectional view of a portion of the internal groove 270 of the injector sleeve 125 shown in FIG. Figure 3 The inner groove depth D defined along the upper flat surface 280 of the inner groove 270 is shown. 凹槽The inner groove 270 may also include an inclined surface 285 extending outward from the inner surface 275 of the injector sleeve 125 to the upper flat surface 280 of the inner groove 270. The inclined surface 285 may be a flat inclined surface and may be at an angle θ relative to the inner surface 275 of the injector sleeve 125. 倾斜 , the angle is in the range of about 20° to about 40°. For example, the angle θ 倾斜 The radius of curvature of the fillet 290 may be about 30°. The fillet 290 extends between the inclined surface 285 and the upper flat surface 280, or in other words, the inclined surface 285 and the upper flat surface 280 meet at the fillet 290. As an example, the radius of curvature of the fillet may be about 4 mm.

[0023] The injector sleeve 125 may be formed of a suitable material to withstand high temperatures, since the area of ​​the cylinder head 115 in which the injector 120 is positioned may be subjected to relatively high heat (i.e., it may be a hot spot). The material of the injector sleeve 125 may have cooling properties so that it may cool the injector 120 and / or other nearby components. For example, the injector sleeve 125 may be made of steel. As another example, the injector sleeve 125 may be formed of heat-treated steel. For example, the internal groove 270 may be formed in the inner surface 275 of the injector sleeve 125 using a lathe.

[0024] Figure 4 Shows Figures 1 to 3 A partial cross-sectional view of a tap-type removal tool 295 and an injector sleeve 125 is shown. Figure 4 The tap-type removal tool 295 shown in FIG. 1 is described in detail in U.S. Pat. No. 9,827,656 and is one example of a removal tool, although other removal tools may be used to remove the injector sleeve 125 of the present invention. Figure 4 As shown, the tap 300 of the tap-type removal tool 295 is inserted into the upper portion 200 of the injector sleeve 125, which is located within the mounting hole 165 of the cylinder head 115. The tap-type removal tool 295 includes a plurality of threads 305 disposed on a distal end 310 thereof. As discussed in more detail below with respect to a method of removing the injector sleeve 125, when the tap 300 of the tap-type removal tool 295 is rotated, threads 305a of the plurality of threads 305 on the distal end 310 of the tap 300 engage or contact the inner groove 270 on the inner surface 275 of the injector sleeve 125. More specifically, as an example, the most distal threads 305a of the plurality of threads 305 disposed on the tap 300 may engage or contact at least the upper flat surface 280 of the inner groove 270, as shown in FIG. Figure 4 Then, the injector sleeve 125 is pulled out of the opening of the cylinder head 115 by pulling the tap-type removal tool 295 upward out of the opening of the cylinder head 115.

[0025] Figure 5A , Figure 5B and Figure 5C Shown in Figure 1 and Figure 3 The ejector sleeve 125 is shown in the removal process as Figure 4 A partial cross-sectional view of a mandrel-type removal tool 320 is shown as an alternative to the tap-type removal tool 295. The mandrel-type removal tool 320 can be used to remove the injector sleeve 125. In particular, Figure 5A The mandrel type removal tool 320 is shown inserted into the injector sleeve 125 in the direction of the arrow. The mandrel type removal tool 320 has an outer tube 325 with a radially extending triangular protrusion 330 at its distal end and an inner tapered hole 335 that accommodates an actuating member 340. The actuating member 340 tapers at its distal end so that the actuating member 340 is moved along the inner tapered hole 335. Figure 5B The upward movement or retraction indicated by arrow B causes the outer tube 325 to move upward and the radially extending triangular protrusions 330 to expand outwardly (as indicated by arrow C) into the recess 270 of the injector sleeve 125 . Figure 5B Retraction of the actuation member 340 relative to the outer tube 325 of the mandrel-type removal tool 320 is shown, thereby expanding the radially extending triangular protrusions 330 at the distal end of the outer tube 325 . Figure 5C Movement or retraction of the outer tube 325 and actuation member 340 and injector sleeve 125 in an upward direction indicated by arrow D away from the mounting aperture 165 of the cylinder head 115 is shown.

[0026] Other types of removal tools may be used to remove the injector sleeve 125. For example, another spindle-type removal tool may be inserted into the injector sleeve 125, and a mechanism (e.g., a screw or a lever) on the head of the removal tool may be applied to expand one or more end effectors (e.g., clamps). The end effectors may be spring biased or may be operated using a hydraulic mechanism and may be operated to expand outward to engage the inner groove 270 of the injector sleeve 125. The injector sleeve 125 is then pulled out of the cylinder head 115 by pulling the spindle-type removal tool upward out of the mounting hole 165 of the cylinder head 115.

[0027] Industrial Applicability

[0028] The injector sleeve 125 of the present invention is configured for use with common rail fuel injectors and can be easily removed from the cylinder head 115 using available removal tools.

[0029] Figure 6600 for removing an injector sleeve 125 according to the present invention. The method 600 may include a step 605 of inserting a tap-type removal tool 295 or a mandrel-type removal tool 320 into the injector sleeve 125 to a predetermined depth or a predetermined distance. The predetermined depth or the predetermined distance may be the distance between the inner groove 270 and the upper end 190 of the injector sleeve 125, or the distance Δ 凹槽 As an example of step 605, Figure 5A Insertion of a mandrel-type removal tool 320 into the injector sleeve 125 in the direction of arrow A is shown.

[0030] The method 600 may also include a step 610 of engaging a surface (e.g., a radially extending triangular protrusion 330) of the tap-type removal tool 295 or the spindle-type removal tool 320 with one or both of the upper flat surface 280 or the inclined surface 285 of the inner groove 270 of the injector sleeve 125. For example, if the tap-type removal tool 295 has a tap 300 having a plurality of threads 305 on a distal end 310 of the tap 300, step 610 may include engaging a thread 305a of the plurality of threads 305 with the upper flat surface 280 of the inner groove 270. More specifically, the most distal thread 305a of the plurality of threads 305 provided on the tap 300 may be engaged with the upper flat surface 280 of the inner groove 270. Also, in the case of using the spindle-type removal tool 320, step 610 may include engaging the actuating member 340 of the spindle-type removal tool 320 along the distal end 310 of the tap 300. Figure 5B The outer tube 325 is retracted into the outer tube 325 in the direction of arrow B in the figure to expand the radially extending triangular protrusions 330 of the outer tube 325 outwardly in the direction of arrow C, i.e., in a direction radially outward from the central axis of the mandrel-type removal tool 320. The radially extending triangular protrusions 330 can then engage with the upper flat surface 280 of the inner groove 270.

[0031] Additionally, the method 600 may include a step 615 of pulling or retracting the tap-type removal tool 295 or the mandrel-type removal tool 320 outwardly from the cylinder head 115 , thereby removing the injector sleeve 125 from the cylinder head 115 . Figure 5C The spindle-type removal tool 320 is shown being pulled in an upward direction indicated by arrow D to remove the removal tool 320 and the injector sleeve 125 from the mounting hole 165 of the cylinder head 115 .

[0032] Although method 600 is described as including steps 605 to 615, additional steps may be included as part of the method. For example, method 600 may include an initial step of removing injector 120, and / or an additional step of cleaning mounting hole 165 of cylinder head 115 after removing injector sleeve 125 and inserting a replacement injector sleeve.

[0033] As described above, the injector sleeve 125 of the present invention is relatively easy to remove using commonly owned and used removal tools, while maintaining sufficient thickness and strength to withstand stress during the removal process and remain compatible with commonly used rail injectors. In particular, with the aid of the internal groove 270 on the upper portion 200 of the injector sleeve 125, a standard removal tool, such as a tap-type removal tool 295 or a mandrel-type removal tool 320, can be inserted into the injector sleeve 125 so that a portion of the removal tool engages or contacts the internal groove 270 of the injector sleeve 125, and the removal tool and the injector sleeve 125 can be easily pulled out of the cylinder head 115. More specifically, the shape of the internal groove 270, including the internal groove depth D 凹槽 , with a fillet of radius R, and a groove length L 凹槽 The dimensions of the ejector sleeve 125 are determined to be partially compatible with commonly used removal tools. Therefore, the ejector sleeve 125 of the present invention does not require specialized tools to be removed.

[0034] In addition, since the inner groove 270 enters the injector sleeve 125 at a predetermined depth or predetermined distance Δ 凹槽 Disposed in the upper portion 200 of the injector sleeve 125, a removal tool such as the tap-type removal tool 295 or the mandrel-type removal tool 320 does not need to be inserted relatively deeply, making the removal process easier and less time-consuming. That is, the removal tool only needs to be inserted until the distal end, such as the distal-most threads 305a of the tap-type removal tool 295 or the radially extending triangular protrusions 325 of the mandrel-type removal tool 320 engage or contact the internal groove 270, rather than having to be inserted deep enough to engage with the lower or distal end of the injector sleeve 125. Since the internal groove 270 is formed in the thickest portion of the injector sleeve 125, the injector sleeve 125 maintains sufficient strength to withstand the stress acting on the injector sleeve 125 during the removal process. Furthermore, because the threads 305 of the tap-type removal tool 295 do not need to form as many or any threads on the inner surface 275 of the injector sleeve 125, and need only engage the inner groove 270, relatively little labor and time is required to insert and engage the removal tool 295 with the inner groove 270. Moreover, because no threads need to be formed on the inner surface 275 of the injector sleeve 125, minimal or no debris is generated, thereby reducing the risk of debris entering the cylinder 110 as a result of the removal process.

[0035] It will be apparent to those skilled in the art that various modifications and variations may be made to the disclosed injector sleeve and associated removal method without departing from the scope of the invention. Other embodiments of the injector sleeve and associated removal method will be apparent to those skilled in the art by consideration of the specification and drawings. The specification, and particularly the embodiments provided herein, are to be considered exemplary only, with the true scope of the invention being indicated by the appended claims and their equivalents.

Claims

1. An injector sleeve for a cylinder head, the injector sleeve comprising: lower part, a middle portion disposed above the lower portion; as well as An upper portion is disposed above the middle portion, the upper portion having a maximum thickness along at least a portion of its length and having a groove on an inner surface of the injector sleeve, the groove having an upper flat surface perpendicular to the longitudinal axis of the injector sleeve.

2. The injector sleeve of claim 1, wherein the groove is the only groove on the inner surface of the injector sleeve.

3. The injector sleeve of claim 1 , wherein the groove extends 360° around the inner surface of the injector sleeve.

4. The injector sleeve of claim 1, wherein the groove further has an inclined planar surface at an angle of about 20° to about 40° relative to the longitudinal axis of the injector sleeve.

5. The injector sleeve of claim 4, wherein a corner where the upper flat surface and the inclined flat surface of the groove meet is a rounded corner.

6. The injector sleeve of claim 5, wherein the radius of curvature of the fillet is approximately 4 mm.

7. The injector sleeve of claim 1, wherein the groove depth into the thickness of the upper portion of the injector sleeve is about 1 mm.

8. The injector sleeve of claim 1, wherein a distance between an upper end of the injector sleeve and the upper flat surface of the groove is about 18 mm or less.

9. A method of removing an injector sleeve from a cylinder head, the method comprising: inserting a removal tool into the injector sleeve in the cylinder head to a predetermined depth of at least 10 mm; engaging a surface of the removal tool with an upper flat surface of a groove on an inner surface of an upper portion of the injector sleeve; as well as The removal tool is pulled outwardly from the cylinder head, thereby removing the injector sleeve from the cylinder head.

10. The method of claim 9, wherein the groove has an inclined flat surface and a rounded corner, an upper flat surface of the groove and the inclined flat surface meet at the rounded corner, the rounded corner having a radius of curvature of about 4 mm.

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