Fuel injection device for engine

Abstract

The present invention provides a technology capable of maintaining good responsiveness and achieving long life in a fuel injection device of an engine. The fuel injection device (100) of the engine comprises: a control rack (55) supported to be able to slide along an axial direction, and capable of adjusting the fuel pressure delivery amount of a fuel pressure delivery mechanism (51) by changing the sliding position in the axial direction; an actuator (40) capable of causing a working part (41) to move forward and backward; and a connecting rod (20) supported by a pivot shaft (25) to be able to swing, and causing the control rack (55) to slide along with the swing of the working part (41) of the actuator (40) moving forward and backward, and having an actuator side connecting part (20A), the connecting rod (20) being connected to the working part (41) of the actuator (40), and the actuator side connecting part (20A) and the working part (41) of the actuator (40) being arranged on the same axis.

Description

Technical Field

[0001] The present invention relates to a fuel injection device for an engine, comprising a control rack supported so as to be able to slide along an axial direction and capable of adjusting the fuel pressure delivery amount of a fuel pressure delivery mechanism by changing the sliding position in the axial direction, an actuator capable of moving a working part forward and backward along a working axis, and a connecting rod supported by a pivot shaft so as to be able to swing and swinging along with the forward and backward movement of the working part of the actuator to slide the control rack. Background Art

[0002] In a diesel engine or the like equipped with a mechanical fuel injection pump, a fuel injection device is provided to control the fuel pressure delivery amount of a fuel pressure delivery mechanism according to engine load control or engine speed control (see, for example, Patent Document 1).

[0003] In such an engine fuel injection device, when the actuator causes the working part to move forward and backward, the connecting rod swings in conjunction with the moving forward and backward movement of the working part. In addition, the control rack slides in the axial direction in conjunction with the swinging movement of the connecting rod. In addition, by controlling the actuator based on a control signal from the engine control unit, the fuel pressure delivery amount of the fuel pressure delivery mechanism can be set to an appropriate amount along with the adjustment of the sliding position of the control rack in the axial direction.

[0004] Patent Document 1: Japanese Patent Application Publication No. 2008-297918

[0005] In conventional fuel injection devices such as the above, the actuator is generally arranged near the center of the device body. However, since the control rack is arranged on the side of the fuel pressure feeding mechanism, the control rack and the connecting rod are arranged at positions offset to the side from the center.

[0006] As a result, there is a case where the point of action of applying a load from the connecting rod to the working axis of the actuator is arranged at a position offset laterally with respect to the working axis of the actuator. With such a structure, when the working part of the actuator is moved forward and backward along the working axis, a relatively large bending moment is applied to the working axis. As a result, the sliding parts of the working axis of the actuator and the like are excessively worn, and the resulting reduction in responsiveness and damage become a problem. Summary of the invention

[0007] In view of such actual conditions, a main object of the present invention is to provide a technology capable of maintaining good responsiveness and extending the life of a fuel injection device of an engine.

[0008] A first characteristic structure of the present invention is a fuel injection device for an engine, comprising:

[0009] a control rack supported to be slidable in an axial direction, and capable of adjusting a fuel pressure delivery amount of a fuel pressure delivery mechanism by changing a sliding position in the axial direction;

[0010] an actuator capable of causing the working portion to move forward and backward along the working axis; and

[0011] The connecting rod is supported by the pivot shaft so as to be swingable, and swings along with the advance and retreat movement of the working part of the actuator to swing the control rack.

[0012] in,

[0013] An actuator-side connecting portion is provided, which connects the working portion of the actuator to the connecting rod.

[0014] The actuator-side connecting portion is arranged on the working shaft of the actuator.

[0015] A rack-side connecting portion is provided, which connects the control rack to the connecting rod.

[0016] The connecting rod has a pair of rod portions, which are supported by the pivot shaft portions and swing in an integral manner, on both sides of the connecting rod sandwiching the working portion of the actuator.

[0017] The pair of rods are connected to the working part of the actuator in a state where a through pin provided between the pair of rods passes through the working part of the actuator to form the actuator-side connecting part.

[0018] The rack connection portion is configured such that an extension portion formed by extending one side of the pair of rods in a longitudinal direction of the rods to a side opposite to the pivot shaft portion is connected to the control rack via an arm.

[0019] According to this structure, when the working part of the actuator is moved forward and backward along the working axis to swing the connecting rod, a load is applied from the connecting rod to the working axis of the actuator along the working axis in the actuator side connection part. As a result, the bending moment applied to the working part of the actuator can be reduced, thereby suppressing excessive wear of the sliding parts of the actuator.

[0020] Therefore, according to the present invention, it is possible to realize a fuel injection device for an engine that can maintain good responsiveness and achieve a long life.

[0021] In addition, the connecting rod has a pair of rods that swing integrally, and the pair of rods connect the working part of the actuator from both sides sandwiching the working part, thereby constituting the above-mentioned actuator-side connecting part. As a result, a load is applied to the working axis of the actuator from both sides in a substantially balanced manner along the working axis. As a result, in the actuator-side connecting part, a load can be applied from the connecting rod to the working axis of the actuator along the working axis.

[0022] In addition, a reasonable structure is adopted in which the two ends of a through pin passing through the working part of the actuator are respectively fixed to a pair of rod portions arranged on both sides sandwiching the working part, thereby forming an actuator-side connecting portion in which the pair of rod portions are connected to the working part of the actuator, thereby achieving the reduction of the bending moment applied to the working axis of the actuator.

[0023] The second characteristic structure of the present invention is that a biasing member is provided, which biases the connecting rod toward one side in the swinging direction of the connecting rod.

[0024] The urging member is connected to the rack-side connecting portion.

[0025] A force applying member is provided, which applies force to the connecting rod toward one side of the swing direction of the connecting rod, and the force applying member is arranged on the same plane orthogonal to the axis center of the swing axis of the connecting rod relative to the connection part of the connecting rod and the center of the working part of the actuator.

[0026] According to the present structure, since a force-applying member is provided to apply force to one side of the connecting rod in the swinging direction, the connecting rod can be prevented from loosening, and the smooth sliding of the control rack can be achieved. Moreover, when such a force-applying member is provided, since the force-applying member is arranged on the same plane orthogonal to the axis of the swinging axis of the connecting rod relative to the connection part of the connecting rod and the center of the working part of the actuator, even if a force from the force-applying member is applied to the connecting rod, since the force is transmitted to the working axis of the actuator as a load along the working axis instead of being transmitted as a bending moment, the progress of the wear of the sliding part of the actuator caused by the bending moment can be suppressed.

[0027] The connection portion of the urging member on the opposite side of the connection portion connected to the link can be fixed to an appropriate position, but if it is directly fixed to the main body of the actuator, for example, the bending moment applied to the operating axis of the actuator can be further reduced.

[0028] A third characteristic structure of the present invention is that an insertion port for inserting the penetration pin into the actuator-side connecting portion is formed on a side wall portion of a housing portion for housing the operating portion of the actuator.

[0029] In the assembly operation of the actuator-side connecting portion formed by allowing a through pin provided between a pair of rods to penetrate the working portion of the actuator as described above, when the through pin is inserted from the lateral side of the pair of rods, the side wall of the accommodating portion located on the lateral side may become an obstacle.

[0030] Therefore, according to this structure, since the insertion port is formed in the side wall of the receiving portion, the through pin can be inserted from the side of the pair of rods through the insertion port. With this structure, the assembly operation can be simplified, and the space between the side wall of the receiving portion and the pair of rods can be narrowed as much as possible to achieve miniaturization of the device.

[0031] A fourth characteristic structure of the present invention is that the penetration pin is configured to be divisible into a plurality of parts along the axial direction.

[0032] According to this structure, since the through pin is configured to be split into a plurality of parts along the axial direction, during the assembly operation of the actuator-side connecting portion, even if the space for inserting the through pin cannot be sufficiently ensured on the side of the pair of rods, the through pins can be inserted from the side of the pair of rods in a state where the through pins are split. With this structure, the assembly operation can be simplified, and the space between the side wall portion of the housing portion and the pair of rods can be minimized to achieve miniaturization of the device.

[0033] A fifth characteristic structure of the present invention is that the working portion of the actuator has a bearing member through which the penetration pin is inserted.

[0034] The bearing component is configured to be unable to move relative to the working part in the forward and backward direction of the working part, but to be able to slide relative to the working part in a direction perpendicular to the axis of the pivot shaft and passing through the actuator-side connecting part and the rack-side connecting part.

[0035] According to this structure, since the through pin is supported by the bearing member provided in the working part of the actuator, the working part of the actuator and the through pin can be connected in a surface contact manner via the bearing member, thereby avoiding line contact which is an important factor in the progress of wear. In addition, the through pin can be supported in a state where looseness in the advancing and retreating direction of the working part is well prevented and the through pin can slide in a direction orthogonal to the swing axis, thereby enabling the advancing and retreating action of the working part to be appropriately transmitted to the connecting rod via the through pin.

[0036] A sixth characteristic structure of the present invention is that the operating portion of the actuator is configured such that the penetration pin can be inserted into the pin through hole through which the penetration pin penetrates from a hole diameter direction by dividing the operating portion forward and backward along the advancing and retreating direction of the operating portion.

[0037] According to this configuration, by inserting the through pin into the pin through hole from the hole diameter direction in the divided state of the working part and then assembling the working part, no space is required for inserting the through pin from the side, thereby achieving further miniaturization of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1It is a side view showing the structure of a fuel injection device of an engine.

[0039] Figure 2 This is a front view of a housing portion for housing the working portion of the actuator.

[0040] Figure 3 It is a perspective view of a housing portion for housing the working portion of the actuator.

[0041] Figure 4 This is an enlarged view of the connection part on the actuator side.

[0042] Figure 5 This is an enlarged view of an actuator-side connecting portion in another embodiment.

[0043] Figure 6 This is a diagram for explaining the structure of a penetration pin in another embodiment.

[0044] Figure 7 This is a perspective view of a housing portion for housing an operating portion of an actuator in another embodiment.

[0045] Figure 8 It is a perspective view showing the structure of a fuel injection device in another embodiment.

[0046] Fig. 9 It is an enlarged view of a rack-side connecting portion in another embodiment.

[0047] Fig.10 It is an enlarged view of a rack-side connecting portion in another embodiment. DETAILED DESCRIPTION

[0048] Embodiments of the present invention will be described with reference to the drawings.

[0049] like Figure 1 As shown, the fuel injection device 100 of this embodiment is configured to control the fuel injection amount in a diesel engine. The fuel injection device 100 comprises a governor 10 equipped with an actuator 40 whose operation is controlled according to the load control and speed control of the engine; and a fuel pump 50 equipped with a fuel pressure delivery mechanism 51.

[0050] In the fuel pump 50, a plurality of fuel pressure delivery mechanism units 51 are arranged in parallel to intermittently pressure-feed liquid fuel to the nozzles provided in each cylinder of the diesel engine so that the liquid fuel is ejected from the nozzles. Figure 1A control rack 55 for adjusting the amount of fuel pressure delivered from each fuel pressure delivery mechanism 51 to the nozzle of each cylinder is provided on the back side of the plurality of fuel pressure delivery mechanisms 51. The control rack 55 is supported to be slidable along the axis in a posture of crossing the side portions of each plunger 52 of the plurality of fuel pressure delivery mechanisms 51.

[0051] Furthermore, on the plunger 52 side of the plurality of fuel pressure feeding mechanism portions 51 ( Figure 1 A cam shaft 57 having a cam 57a for moving the plunger 52 up and down is supported on the lower side of the cam shaft 57. By rotating the cam shaft 57, the plunger 52 of each fuel pressure-feeding mechanism 51 is pumped (moved up and down) by the cam 57a formed on the cam shaft 57. Thus, the fuel pressure-feeding mechanism 51 can compress the liquid fuel by the pumping of the plunger 52.

[0052] Furthermore, the fuel pressure-feeding mechanism 51 is configured to be able to adjust the fuel pressure-feeding amount by changing the position of the fuel supply port, etc., by changing the sliding position of the control rack 55 in the axial direction.

[0053] In this embodiment, the control rack 55 is slid in the direction from the regulator 10 side toward the fuel pump 50 side in the axial direction ( Figure 1 The right direction in the figure is called the "pressing direction". Conversely, the direction in which the control rack 55 slides from the fuel pump 50 side toward the regulator 10 side in the axial direction ( Figure 1 The left direction in the figure is called the “pulling direction”.

[0054] Moreover, the fuel pressure feeding mechanism 51 is configured such that, for example, if the control rack 55 slides in the pressing direction, the fuel pressure feeding amount is reduced, and conversely, if the control rack 55 slides in the pulling direction, the fuel pressure feeding amount is increased. In addition, a connection end 55a connected to the connecting rod 20 in the housing 10A of the regulator 10 described later is provided at one end of the control rack 55. In addition, an auxiliary spring 56 and the like are provided in the fuel pump 50 for assisting the sliding of the control rack 55 in the pulling direction.

[0055] The regulator 10 is connected to the fuel pump 50 at the connection end 55a side of the control rack 55. Figure 1 as well as Figure 2 As shown, the regulator 10 is formed with a housing portion 10A on the side adjacent to the fuel pump 50 .

[0056] An electric actuator 40 is mounted on the side of the regulator 10 opposite to the fuel pump 50. The actuator 40 has an operating portion 41 disposed in the housing portion 10A of the regulator 10 and is configured to be able to move forward and backward along an operating axis 45 substantially parallel to the sliding direction of the control rack 55.

[0057] The link 20 is provided in the housing portion 10A of the regulator 10. The link 20 is supported so as to be swingable by the pivot shaft portion 25, and the pivot shaft portion 25 has a vertical axis at a position twisted with respect to the sliding direction of the control rack 55. The link 20 supported so as to be swingable is provided with an actuator-side connection portion 20A to which the working portion 41 of the actuator 40 is connected, and a rack-side connection portion 20B to which the connection end portion 55a of the control rack 55 is connected. These connection portions 20A and 20B are arranged side by side in a direction substantially orthogonal to the axis of the pivot shaft portion 25, with the actuator-side connection portion 20A disposed between the pivot shaft portion 25 and the rack-side connection portion 20B.

[0058] In addition, in the connecting rod 20, the direction along the axis of the pivot shaft portion 25 is called the "swing axis direction", and the direction orthogonal to the axis of the pivot shaft portion 25 and passing through the actuator side connection portion 20A and the rack side connection portion 20B is called the "swing axis orthogonal direction".

[0059] One end of a spring 30 (an example of a biasing member) is connected to a predetermined position of the link 20, and the other end of the spring 30 is connected to a connector 31 (see FIG. 1 ) fixed to the bottom side of the housing portion 10A of the regulator 10. Figure 3 . ) connection. That is, the spring 30 applies a force to the connecting rod 20 in a direction toward one side of the swinging direction of the connecting rod 20 to prevent the connecting rod 20 from loosening. In addition, the connecting piece 31 that connects the spring 30 to the bottom side of the accommodating portion 10A can be fixed to an appropriate position of the regulator 10. The connecting portion 31 can also be fixed to the main body side of the actuator 40, for example. In this case, the bending moment applied to the working shaft 45 of the actuator 40 can be further reduced.

[0060] In the fuel injection device 100, when the actuator 40 causes the working portion 41 to move forward and backward along the working axis 45, the connecting rod 20 swings around the pivot shaft portion 25. In addition, the control rack 55 connected to the connecting rod 20 slides in the push-in direction or the pull-out direction as the connecting rod 20 swings. That is, by controlling the actuator 40 based on a control signal from an engine control unit (not shown), the fuel pressure delivery amount of the fuel pressure delivery mechanism 51 can be set to an appropriate amount as the sliding position of the control rack 55 in the axial direction is adjusted.

[0061] The fuel injection device 100 of the present embodiment has a characteristic structure for maintaining good responsiveness and achieving a long life, and the details thereof will be additionally described below.

[0062] The actuator-side connecting portion 20A that connects the operating portion 41 of the actuator 40 to the link 20 is disposed on the axis of the operating shaft 45 of the actuator 40 .

[0063] like Figure 2 as well as Figure 3 As shown in FIG. 1 , the link 20 has a pair of rods 21 on both sides sandwiching the working part 41 of the actuator 40, and the pair of rods 21 are supported by the pivot shaft 25 to swing integrally. In addition, the actuator-side connecting portion 20A is configured to connect the pair of rods 21 to the working part 41 of the actuator 40 in a manner such that the through pin 32 provided between the pair of rods 21 penetrates the working part 41 of the actuator 40.

[0064] On the other hand, the rack-side connecting portion 20B is configured such that one side of the pair of rods 21 is extended to the side opposite to the pivot shaft portion 25, and the extended protruding portion 21a is connected to the connecting end portion 55a of the control rack 55 via the arm 27. In addition, in the present embodiment, the rack-side connecting portion 20B is provided on one side of the pair of rods 21. However, it may be configured such that both of the pair of rods 21 are extended to the side opposite to the pivot shaft portion 25, and the connecting end portion 55a of the control rack 55 is connected to a pin spanned between the two extended protruding portions.

[0065] The connecting rod 20 having a pair of rod portions 21 is formed by bending both sides of a plate-like member in the same direction to form a U-shaped cross section, and the bent portion is formed as a pair of rod portions 21. That is, the pair of rod portions 21 of the connecting rod 20 are formed as plate-like portions arranged on both sides of the working portion 41 in a posture parallel to each other and with the thickness direction along the swing axis direction. In addition, the pair of rod portions 21 are connected by a pair of connecting portions 22 and 23 on both sides of the pivot shaft portion 25 side and the rack-side connecting portion 20B side.

[0066] In the connecting rod 20 thus configured, the in-plane direction of the rod portion 21 is in the direction of the load applied to the pivot shaft portion 25, the actuator-side connecting portion 20A, and the rack-side connecting portion 20B. As a result, the rigidity of the connecting rod 20 with respect to these loads is improved. In addition, the number of connecting portions 22 and 23 connecting the pair of rod portions 21 can also be appropriately changed in consideration of the rigidity of the rod portion 21, etc.

[0067] In the fuel injection device 100 constructed as described above, the working portion 41 of the actuator 40 is made to move forward and backward along the working shaft 45 to swing the connecting rod 20. When the connecting rod 20 is swung in this way, a load is applied to the working portion 41 of the actuator 40 from both sides thereof via the through pin 32 in a roughly balanced manner in the forward and backward directions. That is, in the actuator-side connecting portion 20A, a load is applied from the connecting rod 20 to the working shaft 45 of the actuator 40 along the axis of the working shaft 45. As a result, the bending moment applied to the working shaft 45 of the actuator 40 is reduced, and excessive wear of the sliding parts of the actuator 40 is suppressed. Therefore, it is possible to maintain good responsiveness of the actuator 40, and to suppress damage caused by wear and achieve a long life.

[0068] Furthermore, the spring 30 for preventing the connecting rod 20 from loosening is provided at a position biased from the axis of the working shaft 45 of the actuator 40 in a direction perpendicular to the swing axis at the connection position relative to the connecting rod 20. Specifically, the spring 30 is connected to the connecting rod 20 at the connection portion 22 on the rack side connecting portion 20B side of the pair of connecting portions 22 and 23 connecting the pair of rod portions 21. Furthermore, the connection position of the spring 30 relative to the connecting rod 20 and the center of the working portion 41 of the actuator 40 are arranged on the same plane F perpendicular to the swing axis of the connecting rod 20 (refer to FIG. 1 ). Figure 2 .)superior.

[0069] That is, the force applied from the spring 30 to the connecting rod 20 is appropriately transmitted to the working shaft 45 of the actuator 40 as a load along the axis of the working shaft 45 without generating a bending moment that becomes a significant factor causing wear. In addition, the connection position of the spring 30 with respect to the connecting rod 20 can be appropriately changed, for example, Figure 7 As shown, the spring 30 can be connected to the rack-side connecting portion 20B. In addition, when the looseness of the link 20 is not a problem or the looseness can be suppressed by other means, the spring 30 can be appropriately omitted.

[0070] like Figure 2 as well as Figure 3 As shown, an insertion port 12 is formed in the side wall portion 11 of the housing portion 10A for housing the working portion 41 of the actuator 40, at a position in the axial direction of the through pin 32 of the actuator-side connecting portion 20A. The insertion port 12 is provided for inserting the through pin 32 into the actuator-side connecting portion 20A. By forming such an insertion port 12, during the assembly operation of the actuator-side connecting portion 20A, even if the space between the side wall portion 11 of the housing portion 10A and the pair of rod portions 21 is narrow, the through pin 32 can be easily inserted from the side of the pair of rod portions 21 through the insertion port 12. In addition, after the assembly operation, the insertion port 12 can be blocked by a plug 15 or the like.

[0071] Furthermore, when the penetration pin 32 can be inserted into the operating portion 41 without using the insertion port 12 during the assembly work, the insertion port 12 can be omitted.

[0072] like Figure 4 As shown, in the actuator side connection part 20A of the connecting rod 20, a pin through hole 41a is formed in the working part 41 of the actuator 40, which is formed in length in the direction perpendicular to the swing axis and is penetrated parallel to the swing axis center direction. A bearing component 42 is provided in the pin through hole 41a, and the bearing component 42 cannot move relative to the working part 41 along the advance and retreat direction of the working part 41, but can slide relative to the working part 41 along the length direction of the pin through hole 41a, that is, the direction perpendicular to the swing axis. In addition, a through pin 32 supported by the rod part 21 is inserted through the hole formed in the bearing component 42.

[0073] That is, the working part 41 of the actuator 40 and the through pin 32 can be connected in a surface contact manner via the bearing member 42, avoiding line contact which is an important factor in the wear. In addition, since the through pin 32 is supported by the bearing member 42 that can slide along the direction orthogonal to the swing axis, it is supported in a state where it is well prevented from loosening along the advance and retreat direction of the working part 41 and can slide along the direction orthogonal to the swing axis. As a result, the advance and retreat movement of the working part 41 can be appropriately transmitted to the connecting rod 20 via the through pin 32. In addition, such a bearing member 42 can also be omitted and configured so that the through pin 32 is directly inserted into the pin through hole 41a, or the shape, structure, etc. can be changed.

[0074] In addition, in the present embodiment, the operating portion 41 of the actuator 40 is formed as one body, but for example Figure 5 As shown, it can be configured to be divisible forward and backward along the advancing and retreating direction of the working part 41. That is, in this structure, the working part 41 is configured as a part that can be divided relative to the base end part 42B on the base end side, with the central part of the pin through hole 41a as the boundary. The above-mentioned end part 41A and the base end part 42B can be connected to form a whole by a plurality of screws 41C. Moreover, in a state where the working part 41 is separated, the bearing part 42 with the through pin 32 inserted in the pin through hole 41a can be inserted and configured from the hole diameter direction. After that, by assembling the working part 41, there is no need for a space for inserting the through pin 32 from the side.

[0075] The through pin 32 inserted into the working portion 41 of the actuator 40 can be formed as one piece. Figure 6As shown, it can be constructed to be divisible into multiple parts along the axial direction. That is, the through pin 32 is constructed to be divisible into two pin components 33, and each of the divided pin components 33 is constructed to be T-shaped, consisting of a head 33a that abuts against the outer side of the rod portion 21 material, and a shaft portion 33b extending from the head 33a. Moreover, these two pin components 33 are constructed to be connectable by a screw portion 33c formed at the end of the shaft portion 33b. By adopting such a through pin 32, even if there is a situation where the space for inserting the through pin 32 cannot be sufficiently ensured on the side of the pair of rod portions 21, it is possible to connect the rod portion 21 to the working portion 41. Such connection is achieved by inserting the two pin components 33 from the outer side of the pair of rod portions 21 into the inner side of the working portion 41 (refer to Figure 6 (a). ) and screw the screw portion 33c at the distal end of the shaft portion 33b to connect (refer to Figure 6 (b). ) to proceed.

[0076] [Other implementation methods]

[0077] Other embodiments of the present invention will be described. In addition, the configurations of the embodiments described below are not limited to being applied individually, but can also be applied in combination with the configurations of other embodiments.

[0078] (1) Regarding the structure of the link 20 and the actuator-side connecting portion 20A and the rack-side connecting portion 20B in the link 20, based on Figure 8 Other embodiments different from the above-mentioned embodiment will be described in addition, but description of the same structure as the above-mentioned embodiment will be omitted.

[0079] exist Figure 8 In the connecting rod 20 shown, similarly to the above-mentioned embodiment, both sides of the plate-like member are bent in the same direction to form a U-shaped cross section, and the bent portion is provided as a pair of rod portions 21. Moreover, the pair of rod portions 21 are connected only by the connecting portion 23 on the side of the pivot shaft portion 25, and can swing integrally.

[0080] A rack-side connection portion 20B to which the control rack 55 is connected via the arm 27 is provided at the distal end of one side of the pair of rod portions 21. A spring 30 for preventing the link 20 from loosening is connected to the rack-side connection portion 20B.

[0081] exist Figure 8 The illustrated actuator 40 has a disc-shaped base plate portion 43 mounted on an operating portion 41 , and a pair of protrusions 44 protruding toward the pair of rod portions 21 are provided at a position closer to the distal end of the base plate portion 43 .

[0082] Moreover, the U-shaped receiving component 37 composed of a pair of side portions 37A arranged along the inner side of the rod portion 21 and a connecting portion 37B connecting the base ends of these side portions 37A to each other can be rotatably installed between the pair of rod portions 21 through an axis portion 37C arranged on the terminal side of each side portion 37A.

[0083] With such a structure, in the assembly operation of attaching the connecting rod 20, the side portion 37A of the connecting member 37 can be simply inserted between the base plate portion 43 and the protruding portion 44 in the working portion 41 of the actuator 40 while rotating the receiving member 37 around the shaft portion 37C. Moreover, by assembling the connecting rod 20 in this way, the forward and backward movement of the working portion 41 can be appropriately transmitted to the connecting rod 20 via the receiving member 37.

[0084] Furthermore, if the protruding portion 44 of the operating portion 41 is configured to be rotatable about the central axis of the operating portion 41 or is configured to be removable from the base plate portion 43 with a spring interposed therebetween, the assembly work of the link 20 is further simplified.

[0085] (2) Regarding the structure of the rack-side connecting portion 20B, based on Fig. 9 as well as Fig.10 , additional descriptions are given of other embodiments different from the above-mentioned embodiments. However, descriptions of the same structures as the above-mentioned embodiments are omitted.

[0086] exist Fig. 9 In the rack-side connecting portion 20B shown, a through pin 35 is provided between a pair of rod portions 21, and a spring 30 for preventing the connecting rod 20 from loosening is connected to the central portion of the through pin 35, and an arm 27 for connecting the control rack 55 is connected to the end of the through pin 35. With this structure, the rigidity of the connecting rod 20 is further improved, and the pair of connecting rod portions 21 swing more integrally in the rack-side connecting portion 20B. In addition, the connection portion of the spring 30 relative to the connecting rod 20 is a portion offset from the center of the working portion 41 of the actuator 40 in a direction orthogonal to the swing axis, and the connection portion of the spring 30 and the center of the working portion 41 of the actuator 40 are arranged on the same plane F orthogonal to the swing axis of the connecting rod 20. As a result, the bending moment applied to the working axis of the actuator 40 can be reduced.

[0087] In addition, Fig. 9 In the illustrated structure, since the end of the through pin 35 is connected to the control rack 55 side, the through pin 35 slightly rotates and swings when the link 20 swings, and friction is generated between the through pin 35 and the connection part of the spring 30.

[0088] Therefore, the friction between the spring 30 and the penetration pin 35 can be reduced without directly connecting the spring 30 to the penetration pin 35 .

[0089] For example, in Fig.10In the rack-side connecting portion 20B shown, a cylindrical member 36 is provided between a pair of rods 21, and a through pin 35 is inserted through the cylindrical member 36. Furthermore, a spring 30 is connected to the central portion of the cylindrical member 36, and an arm 27 for connecting the control rack 55 is connected to the end of the through pin 35. With this structure, even when the through pin 35 swings and rotates, friction between the spring 30 and the cylindrical member 36 can be avoided.

[0090] (3) In the above embodiment, if Figure 2 As shown, in the link 20 , a plane passing through the center of the rack-side connecting portion 20B, which is a plane orthogonal to the pivot shaft portion 25 , is laterally offset from a plane passing through the center of the actuator-side connecting portion 20A.

[0091] On the other hand, for example, the pivot shaft portion 25 may be rotated in an inclined manner in the axial direction so that these surfaces become the same. With such a configuration, the force acting on the rack-side connecting portion 20B can be appropriately transmitted to the operating shaft 45 of the actuator 40 as a load along the operating shaft 45 without generating a bending moment that becomes a significant factor causing wear.

[0092] The present invention can be applied to a fuel injection device of an engine.

[0093] Description of reference numerals:

[0094] 10A...accommodating portion; 11...side wall portion; 12...insertion port; 20...connecting rod; 20A...actuator-side connecting portion; 20B...rack-side connecting portion; 21...rod portion; 25...pivot shaft portion; 30...spring (force-applying member); 32...through pin; 40...actuator; 41...working portion; 41a...pin through hole; 42...bearing member; 45...working shaft; 51...fuel pressure-delivery mechanism portion; 55...control rack; 100...fuel injection device; F...plane.

Claims

1. A fuel injection device for an engine, have: a control rack supported to be slidable in an axial direction, and capable of adjusting a fuel pressure delivery amount of a fuel pressure delivery mechanism by changing a sliding position in the axial direction; an actuator capable of causing the working portion to move forward and backward along the working axis; and The connecting rod is supported by the pivot shaft so as to be swingable, and swings along with the advance and retreat movement of the working part of the actuator to slide the control rack. It is characterized in that An actuator-side connecting portion is provided, which connects the working portion of the actuator to the connecting rod. The actuator-side connecting portion is arranged on the working shaft of the actuator. The connecting rod has a pair of rod portions, which are supported by the pivot shaft portions and swing in an integral manner, on both sides of the connecting rod sandwiching the working portion of the actuator. The pair of rods are connected to the working part of the actuator to form the actuator-side connecting part. The through pin provided between the pair of rods is passed through the working part of the actuator to form the actuator side connecting part. The working part of the actuator has a bearing member through which the through pin is inserted. The bearing component is configured to be unable to move relative to the working part in the forward and backward direction of the working part, but to be able to slide relative to the working part in a direction perpendicular to the axis of the pivot shaft and passing through the actuator-side connecting part and the rack-side connecting part.

2. The fuel injection device for an engine according to claim 1, wherein: A biasing member is provided, which biases the connecting rod toward one side of the swinging direction of the connecting rod, The urging member is disposed on the same plane perpendicular to the axis of the swing shaft of the link relative to the connection portion of the link and the center of the operating portion of the actuator.

3. The fuel injection device for an engine according to claim 1 or 2, wherein: An insertion port for inserting the penetration pin into the actuator-side connecting portion is formed on a side wall portion of a housing portion for housing the operating portion of the actuator.

4. The fuel injection device for an engine according to claim 1 or 2, wherein: The penetration pin is configured to be divisible into a plurality of parts along the axial direction.

5. The fuel injection device for an engine according to claim 1 or 2, wherein: The operating portion of the actuator is configured such that the penetration pin can be inserted from a hole diameter direction into a pin through hole through which the penetration pin penetrates by dividing the operating portion frontward and rearward along the advancing and retreating direction of the operating portion.

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