JP6395218B2 - Component incorporated in fuel injection system and fuel injection system - Google Patents

Description

  The present invention relates to a component such as an injector or a common rail that is incorporated in a fuel injection system, and a fuel injection system in which the component is incorporated.

  As a component incorporated in a conventional fuel injection system, for example, a base having an opening and an internal channel communicating with the opening, and one end connected to the opening and the other end of a pipe through which fuel flows And a cylindrical body connected to each other. A female screw portion is formed on the inner peripheral surface of the opening. Moreover, a male screw part is formed in each of the side close | similar to the opening part of the outer peripheral surface of a cylindrical body, and a far side. A male thread portion is formed on the outer peripheral surface of the pipe through which the fuel flows. The cylindrical body and the opening are connected to each other by coupling the male screw portion on the side close to the opening on the outer peripheral surface of the cylindrical body to the female screw portion of the opening. Further, the tubular body and the pipe are connected by coupling the male thread portion on the side far from the opening on the outer peripheral surface of the tubular body to the female thread portion of the lock ring attached to the pipe ( For example, see Patent Document 1.)

JP 2006-233900 A (paragraphs [0025] to [0028], FIG. 4)

  In the components incorporated in the conventional fuel injection system, when the pipe is removed from the cylindrical body for replacement of the component, that is, when the lock ring attached to the pipe is turned, the cylindrical body is attached together with the lock ring. As a result, the sealing performance between the cylindrical body and the base body is not ensured. That is, in the conventional fuel injection system, when removing the pipe from the tubular body, it is necessary to turn the lock ring while preventing the tubular body from rotating with respect to the base body, and there is a problem that workability is low.

  The present invention has been made against the background of the above problems, and provides a component incorporated in a fuel injection system with improved workability when a pipe is removed from a tubular body. In addition, a fuel injection system incorporating such components is obtained.

  The component incorporated in the fuel injection system according to the present invention includes a base having an opening in which a first female screw portion is formed, an internal flow path communicating with the opening, and a first male screw portion. A cylindrical body having one end connected to the opening by coupling the first male screw portion and the first female screw portion and the other end connected to a pipe through which fuel flows. An annular body is disposed outside the cylindrical body, the annular body is connected to the base body, and the cylindrical body is directed toward the back side of the opening by the annular body. Is pressed.

  The fuel injection system according to the present invention incorporates the above components.

  In the component incorporated in the fuel injection system according to the present invention, an annular body is disposed outside the tubular body, the annular body is connected to the base body, and the tubular body is connected to the back of the opening by the annular body. It is pressed toward the side. Therefore, for example, even when the lock ring attached to the pipe is turned to remove the pipe from the cylindrical body, the cylindrical body is prevented from rotating with the lock ring by the annular body. Therefore, workability is improved.

It is a figure for demonstrating the whole structure of the fuel-injection system which concerns on Embodiment 1 of this invention. It is a figure for demonstrating the structure of the component of the fuel-injection system which concerns on Embodiment 1 of this invention. It is a figure for demonstrating the structure of the principal part of a component of the fuel-injection system which concerns on Embodiment 1 of this invention. It is a figure for demonstrating the structure of the principal part of a component of the fuel-injection system which concerns on Embodiment 3 of this invention.

Hereinafter, a fuel injection system according to the present invention will be described with reference to the drawings.
The configuration described below is an example, and the component and the fuel injection system according to the present invention are not limited to such a configuration. Moreover, in each figure, the same code | symbol is attached | subjected to the same or similar member or part. Further, the illustration of the fine structure is simplified or omitted as appropriate. In addition, overlapping descriptions are simplified or omitted as appropriate.

Embodiment 1 FIG.
The fuel injection system according to Embodiment 1 will be described below.
<Overall configuration of fuel injection system>
The overall configuration of the fuel injection system according to Embodiment 1 will be described.
FIG. 1 is a diagram for explaining the overall configuration of the fuel injection system according to the first embodiment.

  As shown in FIG. 1, the fuel injection system 1 includes a fuel tank 11, a supply pump 12, a main filter 13, a cassette type pump 14, a common rail 15, and a plurality of injectors 16, by a pipe 17. It is connected.

  The fuel in the fuel tank 11 is pumped up by the supply pump 12 and then flows into the cassette type pump 14 through the main filter 13. The fuel flowing into the cassette type pump 14 is increased in pressure in a fuel pressurizing chamber (not shown) of the cassette type pump 14, and is sent to the common rail 15 and accumulated. The accumulated fuel is supplied at an equal pressure to each of the plurality of injectors 16 with the pressure adjusted by a pressure regulating valve (not shown). The fuel supplied to the injector 16 is injected into the cylinder of the internal combustion engine by opening a fuel injection hole (not shown) of the injector 16.

  That is, the fuel injection system 1 is a system for injecting fuel into an internal combustion engine such as a diesel engine, and includes components such as a common rail 15 that functions as a pressure accumulator and an injector 16 that functions as a fuel injection unit. The high-pressure fuel is supplied to components such as the common rail 15 that functions as a pressure accumulator and the injector 16 that functions as a fuel injection unit.

<Component configuration>
Configurations of components of the fuel injection system according to Embodiment 1 will be described.
FIG. 2 is a diagram for explaining the configuration of components of the fuel injection system according to the first embodiment. FIG. 3 is a diagram for explaining a configuration of a main part of the component of the fuel injection system according to the first embodiment.

  As shown in FIGS. 2 and 3, the injector 16, which is a component of the fuel injection system 1, has a base 21 in which an opening 31, an internal flow path 32, a fuel injection hole 33, and a fuel return hole 34 are formed. And a cylindrical body 22 having one end connected to the opening 31 and an annular body 23 disposed outside the cylindrical body 22. A pipe 17 is connected to the other end of the cylindrical body 22.

  In the internal flow path 32, the inlet flow path 32 a communicating with the opening 31 branches into an injection flow path 32 b communicating with the fuel injection hole 33 and a recirculation flow path 32 c communicating with the fuel recirculation hole 34. . The injection flow path 32 b is opened and closed by the piston 35, and the reflux flow path 32 c is opened and closed by the piston 36. The high-pressure fuel that passes through the pipe 17 flows into the internal flow path 32 through the inside of the cylindrical body 22. When the piston 36 closes the recirculation flow path 32 c, the injection flow path 32 b is closed by the piston 35. On the other hand, when the piston 36 opens the recirculation flow path 32c, the injection flow path 32b is opened, and the fuel that has flowed into the internal flow path 32 is injected from the fuel injection hole 33 and the pipe 17 is connected from the fuel recirculation hole 34. To the fuel tank 11.

  The cylindrical body 22 has a hollow portion 22a that penetrates in the axial direction and has an end portion on the side far from the internal flow path 32 expanding in a tapered shape. A first male screw portion 22b is formed in a region near the internal flow path 32 on the outer peripheral surface of the cylindrical body 22, and a third male screw portion is formed in a region far from the internal flow path 32. 22c is formed. An annular protrusion 22d is formed in a region between the first male screw portion 22b and the third male screw portion 22c on the outer peripheral surface of the cylindrical body 22. The outer peripheral surface of the annular protrusion 22d may have a shape that fits with the fastener.

  The opening 31 is formed with a first female screw portion 31a and a second female screw portion 31b. The first female screw portion 31 a is formed in a region near the internal flow path 32 on the inner peripheral surface of the opening 31, and the second female screw portion 31 b is an internal flow path on the inner peripheral surface of the opening 31. It is formed in a region far from 32. When the first male screw portion 22b and the first female screw portion 31a are coupled, the end surface of the cylindrical body 22 on the side close to the internal flow path 32 comes into contact with the bottom surface of the opening portion 31, so that the cylindrical shape The body 22 is connected to the base body 21. A biting edge may be formed on the end surface of the cylindrical body 22 near the internal flow path 32, and the biting edge may be in direct contact with the bottom surface of the opening 31. The end surface on the side close to the flow path 32 may abut on the bottom surface of the opening 31 in a state where the sealing material is interposed. That is, as long as the sealing property of the fuel flowing into the internal flow path 32 from the hollow portion 22a is ensured, other modes may be used.

  A tapered portion 17a that is gradually narrowed is formed on the outer peripheral surface of the end portion of the pipe 17 connected to the cylindrical body 22. An annular protrusion 17b is formed in a region of the outer peripheral surface of the pipe 17 on the side far from the cylindrical body 22 with respect to the tapered portion 17a. The lock ring 19 is attached to the pipe 17 by press-fitting the press-fit ring 18 from the end side in a state where the end of the pipe 17 is inserted into the through-hole 19a of the lock ring 19. A third female screw portion 19 b is formed on the inner peripheral surface of the lock ring 19. It is preferable that at least a part of the outer peripheral surface of the lock ring 19 has a shape that fits with a fastener such as a hexagon wrench. When the third female screw portion 19b and the third male screw portion 22c are coupled, the tapered portion 17a comes into contact with the tapered region of the hollow portion 22a, and the pipe 17 is connected to the cylindrical body 22. The The set of the first male screw portion 22b and the first female screw portion 31a and the set of the third male screw portion 22c and the third female screw portion 19b have the same screw direction. The tapered portion 17a may directly contact the tapered region of the hollow portion 22a, or may contact with the sealing material interposed. That is, as long as the sealing property of the fuel flowing from the pipe 17 into the hollow portion 22a is ensured, other modes may be used.

  The annular body 23 has a through portion 23 a, and the through portion 23 a surrounds the outer peripheral surface of the cylindrical body 22 in a state where the cylindrical body 22 before the pipe 17 is connected is connected to the base body 21. It is arranged as follows. A second male screw portion 23 b is formed in a region of the outer peripheral surface of the annular body 23 on the side close to the opening 31. The inner diameter of the through portion 23a is smaller than the outer diameter of the annular protrusion 22d. A region of the outer peripheral surface of the annular body 23 on the side far from the opening 31 may have a shape that fits with a fastener such as a hexagon wrench. When the second male screw portion 23b and the second female screw portion 31b are coupled, the end portion of the penetrating portion 23a on the side close to the opening portion 31 comes into contact with the end surface on the side farther from the opening portion 31 of the annular protrusion 22d. In this state, the annular body 23 is connected to the base body 21. That is, the cylindrical body 22 is pressed toward the inner side of the opening 31 by the annular body 23 connected to the base body 21.

  The direction of the screws of the set of the first male screw portion 22b and the first female screw portion 31a and the set of the second male screw portion 23b and the second female screw portion 31b are opposite. Moreover, the contact part of the edge part near the opening part 31 of the penetration part 23a and the end surface far from the opening part 31 of the cyclic | annular protrusion 22d is linear. That is, the part pressed by the annular body 23 of the cylindrical body 22 is linear. Further, individual information of the injector 16 (information on correction values for individual differences, etc.) is imprinted on the exposed portion of the annular body 23. The individual information is, for example, a matrix type two-dimensional code.

<Operation of fuel injection system>
The operation of the fuel injection system according to Embodiment 1 will be described.
The injector 16 incorporated in the fuel injection system 1 has a base 21 having an opening 31 and an internal flow path 32, one end connected to the opening 31, and the other end connected to a pipe 17 through which fuel flows. A cylindrical body 22. In the injector 16, an annular body 23 is disposed outside the cylindrical body 22, the annular body 23 is connected to the base body 21, and the cylindrical body 22 is opened by the annular body 23. It is pressed toward the back side. Therefore, for example, even when the lock ring 19 attached to the pipe 17 is rotated in order to remove the pipe 17 from the cylindrical body 22, the cylindrical body 22 is moved by the pressing force of the annular body 23. Since the rotation with the lock ring 19 is suppressed, workability is improved.

  In addition, when the pipe 17 is removed from the cylindrical body 22, it is possible to fundamentally avoid that the cylindrical body 22 rotates together with the lock ring 19 by integrating the base body 21 and the cylindrical body 22. Is possible. However, in such a case, the shape of the base 21 is complicated. That is, in the injector 16, since the workability can be ensured even though the base body 21 and the cylindrical body 22 are separate bodies, cost efficiency is improved. In addition, when the pipe 17 is removed from the cylindrical body 22, the cylindrical body 22 rotates together with the lock ring 19, so that a locking sleeve is provided in the gap between the inner peripheral surface of the opening 31 and the outer peripheral surface of the cylindrical body 22. It is possible to avoid it fundamentally by press-fitting. However, in such a case, a special process is required, and the member needs to be discarded every time a press-fitting error occurs. In other words, the injector 16 can achieve both workability and productivity.

  Further, in the injector 16 incorporated in the fuel injection system 1, the set of the first male screw portion 22b and the first female screw portion 31a, and the set of the second male screw portion 23b and the second female screw portion 31b are: The screw direction is reversed. Therefore, for example, even when the lock ring 19 attached to the pipe 17 is turned to remove the pipe 17 from the cylindrical body 22, the second male screw portion 23b and the second female screw portion 31b Since the coupling between the first male screw portion 22b and the first female screw portion 31a is suppressed from being loosened, and the decrease in the pressing force of the annular body 23 is suppressed, As a result, it is ensured that the rod 22 rotates together with the lock ring 19, and the fuel sealing performance is ensured.

  Further, in the injector 16 incorporated in the fuel injection system 1, the portion pressed by the annular body 23 of the cylindrical body 22 is linear. In particular, when the lock ring 19 is connected to the cylindrical body 22 in a state where the annular body 23 is connected to the base body 21, the frictional force acting on the contact portion between the annular body 23 and the cylindrical body 22 is large. As a result, an error occurs in the tightening torque of the lock ring 19 and the securing of the fuel sealing performance is uncertain. When the portion pressed by the annular body 23 of the cylindrical body 22 is linear, the frictional force is reduced, so that an error occurs in the tightening torque of the lock ring 19 and the fuel It is suppressed that securing of the sealing performance is uncertain.

  In addition, in the injector 16 incorporated in the fuel injection system 1, individual information of the injector 16 (information on correction values for individual differences, etc.) is imprinted on the exposed portion of the annular body 23. Therefore, it is not necessary to discard relatively large members such as the base body 21 and the cylindrical body 22 every time a marking error is made, and the cost efficiency is improved.

  In the above, the case where the component having the above-described characteristics is the injector 16 is described. However, the component having the above-mentioned characteristics is another component such as the common rail 15 to which high-pressure fuel is supplied. It may be. That is, the common rail 15 incorporated in the fuel injection system 1 has one end connected to the base 21 having the opening 31 and the internal flow path 32 and the opening 31 and the other end connected to the pipe 17 through which the fuel flows. An annular body 23 is disposed outside the cylindrical body 22, the annular body 23 is connected to the base 21, and the cylindrical body 22 is an annular body. 23 may be pressed toward the back side of the opening 31. Even in such a case, the same action as described above occurs.

  When the component having the above-described features is the injector 16, the replacement frequency of the injector 16 is relatively high compared to other components, and the installation location of the injector 16 is relatively high compared to other components. Due to the fact that the workability is low, the above-described action becomes more remarkable. That is, the above-described features are particularly useful when the component is an injector 16.

Embodiment 2. FIG.
The fuel injection system according to Embodiment 2 will be described below.
In addition, the description which overlaps with the fuel injection system which concerns on Embodiment 1 is abbreviate | omitted suitably.

<Component configuration>
Configurations of components of the fuel injection system according to Embodiment 2 will be described.
In the configuration shown in FIG. 3, the set of the first male screw portion 22b and the first female screw portion 31a and the set of the second male screw portion 23b and the second female screw portion 31b are in the direction of the screw. The same. The screw pitch of the set of the second male screw portion 23b and the second female screw portion 31b is smaller than the screw pitch of the set of the first male screw portion 22b and the first female screw portion 31a. Moreover, the contact part of the edge part near the opening part 31 of the penetration part 23a and the end surface far from the opening part 31 of the cyclic | annular protrusion 22d is linear. That is, the part pressed by the annular body 23 of the cylindrical body 22 is linear.

<Operation of fuel injection system>
The operation of the fuel injection system according to Embodiment 2 will be described.
In the injector 16 incorporated in the fuel injection system 1, the set of the first male screw portion 22b and the first female screw portion 31a and the set of the second male screw portion 23b and the second female screw portion 31b are screwed. Are in the same direction. The screw pitch of the set of the second male screw portion 23b and the second female screw portion 31b is smaller than the screw pitch of the set of the first male screw portion 22b and the first female screw portion 31a. Therefore, for example, even when the lock ring 19 attached to the pipe 17 is turned to remove the pipe 17 from the cylindrical body 22, the second male screw portion 23b and the second female screw portion 31b Since the coupling between the first male screw portion 22b and the first female screw portion 31a is suppressed from being loosened, and the decrease in the pressing force of the annular body 23 is suppressed, As a result, it is ensured that the rod 22 rotates together with the lock ring 19, and the fuel sealing performance is ensured.

  In addition, the screw direction of the set of the first male screw portion 22b and the first female screw portion 31a and the set of the second male screw portion 23b and the second female screw portion 31b are the same. The second male screw portion 23b and the second female screw portion 31b can be coupled without loosening the coupling between the first male screw portion 22b and the first female screw portion 31a. Therefore, it is possible to further ensure the sealing performance of the fuel flowing into the internal flow path 32 from the hollow portion 22a.

  Further, in the injector 16 incorporated in the fuel injection system 1, the portion pressed by the annular body 23 of the cylindrical body 22 is linear. In particular, when the lock ring 19 is connected to the cylindrical body 22 in a state where the annular body 23 is connected to the base body 21, the frictional force acting on the contact portion between the annular body 23 and the cylindrical body 22 is large. As a result, an error occurs in the tightening torque of the lock ring 19 and the securing of the fuel sealing performance is uncertain. When the portion pressed by the annular body 23 of the cylindrical body 22 is linear, the frictional force is reduced, so that an error occurs in the tightening torque of the lock ring 19 and the fuel It is suppressed that securing of the sealing performance is uncertain.

  In addition, when the frictional force acting on the contact portion between the annular body 23 and the cylindrical body 22 is large, when the lock ring 19 attached to the pipe 17 is turned in order to remove the pipe 17 from the cylindrical body 22 In addition, the coupling between the second male screw portion 23b and the second female screw portion 31b is loosened, and the pressing force of the annular body 23 is reduced. When the portion pressed by the annular body 23 of the cylindrical body 22 is linear, the frictional force is reduced, so that the pressing force of the annular body 23 is reduced and the fuel seal is reduced. It is suppressed that securing of the property is uncertain.

Embodiment 3 FIG.
The fuel injection system according to Embodiment 3 will be described below.
In addition, the description which overlaps with the fuel injection system which concerns on Embodiment 1 is abbreviate | omitted suitably.

<Component configuration>
The configuration of components of the fuel injection system according to Embodiment 3 will be described.
FIG. 4 is a diagram for explaining the configuration of the main components of the fuel injection system according to the third embodiment.

  As shown in FIG. 4, the annular body 23 has a through part 23 a, and the through part 23 a is a cylinder in a state where the cylindrical body 22 before the pipe 17 is connected is connected to the base body 21. It arrange | positions so that the outer peripheral surface of the shape-like body 22 may be enclosed. A plurality of locations outside the through-hole 23a of the annular body 23 are coupled to the base body 21 with screw parts or the like. The inner diameter of the through portion 23a is smaller than the outer diameter of the annular protrusion 22d. When the annular body 23 is connected to the base body 21, that is, when screw parts or the like for fixing a plurality of positions outside the through portion 23a are fastened, the end portion of the through portion 23a on the side close to the opening 31 is an annular protrusion. It will be in the state contact | abutted to the end surface on the side far from the opening part 31 of 22d. That is, the cylindrical body 22 is pressed toward the inner side of the opening 31 by the annular body 23 connected to the base body 21. The outer peripheral surface of the annular body 23 may be circular or may not be circular.

<Operation of fuel injection system>
The operation of the fuel injection system according to Embodiment 3 will be described.
In the injector 16 incorporated in the fuel injection system 1, when screw parts or the like for fixing a plurality of locations outside the through portion 23a are fastened, the end portion of the through portion 23a on the side close to the opening 31 is the annular protrusion 22d. It will be in the state contact | abutted to the end surface on the side far from the opening part 31. FIG. Therefore, for example, even when the lock ring 19 attached to the pipe 17 is rotated in order to remove the pipe 17 from the cylindrical body 22, the cylindrical body 22 is moved by the pressing force of the annular body 23. Since the rotation with the lock ring 19 is suppressed, workability is improved.

  DESCRIPTION OF SYMBOLS 1 Fuel injection system, 11 Fuel tank, 12 Supply pump, 13 Main filter, 14 Cassette type pump, 15 Common rail, 16 Injector, 17 Piping, 17a Tapered part, 17b Annular protrusion, 18 Press-fit ring, 19 Lock ring, 19a Through Part, 19b third female screw part, 21 base, 22 cylindrical body, 22a hollow part, 22b first male screw part, 22c third male screw part, 22d annular projection, 23 annular body, 23a through part, 23b first 2 male screw part, 31 opening part, 31a 1st female screw part, 31b 2nd female screw part, 32 internal flow path, 32a inlet flow path, 32b injection flow path, 32c recirculation flow path, 33 fuel injection hole, 34 fuel Reflux hole, 35 piston, 36 piston.

Claims (9)

Components incorporated into a fuel injection system,
A base having an opening in which a first female thread portion is formed, and an internal flow path communicating with the opening;
A first male screw portion is formed, one end is connected to the opening by coupling the first male screw portion and the first female screw portion, and the other end is connected to a pipe through which fuel flows. A cylindrical body,
With
An annular body is disposed outside the cylindrical body,
The annular body is connected to the base body,
The tubular body, have been pressed toward the rear side of the opening by the annular body,
The opening has a second female screw part,
The annular body has a second male screw portion, and is connected to the base body by coupling of the second male screw portion and the second female screw portion.
component. The set of the second male screw portion and the second female screw portion is reverse in screw direction compared to the set of the first male screw portion and the first female screw portion.
The component of claim 1 . The set of the second male screw part and the second female screw part has the same screw direction and the screw pitch compared to the set of the first male screw part and the first female screw part. Is small,
The component of claim 1 . The portion pressed by the annular body of the cylindrical body is linear.
Component according to any one of claims 1-3. Individual information is stamped on the exposed portion of the annular body,
Component according to any one of claims 1-4. The individual information is a matrix type two-dimensional code.
The component of claim 5 . An injector,
Component according to any one of claims 1-6. Is a common rail,
Component according to any one of claims 1-6. The component according to any one of claims 1 to 8 is incorporated,
Fuel injection system.

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