JP4473839B2 - Fuel injection pump - Google Patents

Description

  The present invention relates to a structure technology of parts around a plunger forming a fuel injection pump in a fuel injection device of a diesel engine using low quality oil as fuel.

2. Description of the Related Art Conventionally, fuel injection pumps that send fuel directly by a plunger are well known. For example, Patent Document 1 discloses this fuel injection pump in a fuel injection device for a diesel engine using low quality fuel.
JP 2002-70692 A

  Some marine engines use high-viscosity low-quality oil called C heavy oil as fuel (low-quality fuel). When such a low quality fuel is used, fuel leaks to the sliding surface between the plunger barrel and the plunger, and the sliding portion of the fuel injection pump (for example, the plunger flange, the pinion rack meshing portion or the plunger barrel and the plunger May stick to the sliding surface). Therefore, in order to prevent such a malfunction, a configuration has been implemented in which lubricating oil is injected to clean the sliding portion of the fuel injection pump.

However, if the lubricating oil is not injected in an appropriate amount and position, the sliding portion of the plunger barrel, plunger, etc. may stick or caking, or it may be affected by deposits of low quality fuel and the plunger collar may be damaged. . Therefore, the problem to be solved is to prevent the sliding portion from sticking and sticking in the fuel injection pump using low-quality fuel, and to prevent the plunger collar from being damaged. Is to improve.

  The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described.

In Claim 1, it is engaged in the plunger barrel (12) which inserted the plunger (14) which slides up and down, the collar part (21) provided in the said plunger (14), and the vertically long groove (53) provided in the lower part. And is elastically supported by a pinion sleeve (50) that rotatably fits the plunger barrel (12), and an upper spring receiver (40) and a spring (25) that are fitted on the pinion sleeve (50). In a fuel injection pump (10) having a plunger guide (23), the upper spring receiver (40) and the upper edge of the plunger guide (23) at the highest lift position in the reciprocating motion of the plunger (14) There configured to abut a structure in which the gap (G) is formed between said flange portion (21) and bran Ja barrel bottom, previously plunger guide (23) The upper spring receiver (40) is brought into contact, and the plunger barrel (12) and the flange (21) are not in contact with each other, and at least one notch (41) is formed on the outer periphery of the upper end surface of the upper spring receiver (40). Is formed .

According to claim 2, in the fuel injection pump according to claim 1, at least two or more intake holes (55, 56) are provided on the outer peripheral surface of the upper and lower middle portions of the pinion sleeve (50). 55, 56) has at least one intake hole provided above the longitudinal groove (53) provided in the pinion sleeve (50), and the intake hole (55) in the lowest position is provided in the pinion sleeve (50). ) And an inclined hole penetrating obliquely downward toward the inner periphery .

The fuel injection pump according to claim 2, wherein a chamfering process is performed on an outer peripheral side of the intake hole (70), and the chamfering process of the intake hole (70) is performed above the lower chamfer area. This is a larger chamfered area .

  As effects of the present invention, the following effects can be obtained.

In Claim 1, it is engaged in the plunger barrel (12) which inserted the plunger (14) which slides up and down, the collar part (21) provided in the said plunger (14), and the vertically long groove (53) provided in the lower part. And is elastically supported by a pinion sleeve (50) that rotatably fits the plunger barrel (12), and an upper spring receiver (40) and a spring (25) that are fitted on the pinion sleeve (50). In a fuel injection pump (10) having a plunger guide (23), the upper spring receiver (40) and the upper edge of the plunger guide (23) at the highest lift position in the reciprocating motion of the plunger (14) There configured to abut a structure in which the gap (G) is formed between said flange portion (21) and bran Ja barrel bottom, previously plunger guide (23) The upper spring receiver (40) is brought into contact, and the plunger barrel (12) and the flange (21) are not in contact with each other, and at least one notch (41) is formed on the outer periphery of the upper end surface of the upper spring receiver (40). since the formation of the, when the plunger and the plunger barrel slides, without the plunger flange portion and the plunger barrel are in contact, it can reliably prevent damage to the plunger flange portion.

The lubricating oil is guided to the outer periphery of the plunger guide by the notches provided on the outer periphery of the spring receiver, and the deposits attached to the outer periphery of the plunger guide can be cleaned. That is, the safety of the fuel injection pump can be improved by preventing the plunger guide from sticking.

According to claim 2, in the fuel injection pump according to claim 1, at least two or more intake holes (55, 56) are provided on the outer peripheral surface of the upper and lower middle portions of the pinion sleeve (50). 55, 56) has at least one intake hole provided above the longitudinal groove (53) provided in the pinion sleeve (50), and the intake hole (55) in the lowest position is provided in the pinion sleeve (50). The slanted hole that penetrates diagonally downward toward the inner periphery of the pinion ), so that most of the lubricating oil is guided to the inner periphery of the pinion by the inclined hole that penetrates obliquely downward at the lowest position of the pinion. The deposit adhering to the part can be cleaned. That is, the safety of the fuel injection pump can be improved by preventing the plunger from sticking.

Further, the lubricating oil is guided to the plunger collar from the intake hole formed in the upper part of the vertical groove 53 having a two-sided width, and the deposit adhering to the plunger collar can be cleaned. That is, damage to the plunger collar can be prevented by removing the deposit on the plunger collar.

The fuel injection pump according to claim 2, wherein a chamfering process is performed on an outer peripheral side of the intake hole (70), and the chamfering process of the intake hole (70) is performed above the lower chamfer area. Since the chamfering area of the pinion is increased, the lubricating oil dripping on the outer periphery of the pinion is guided to the chamfered portion and easily enters the intake hole, so that the lubricating oil is more easily guided to the inner peripheral portion of the pinion. That is, the safety of the fuel injection pump can be improved by preventing the plunger from sticking.

  Further, the lubricating oil is easily guided to the inner periphery of the pinion. That is, the safety of the fuel injection pump can be improved by preventing the plunger from sticking.

  Next, embodiments of the invention will be described.

  FIG. 1 is a side sectional view showing an overall configuration of a fuel injection pump according to the present invention, FIG. 2 is a side sectional view showing a detailed configuration of a lower portion of a plunger according to an embodiment of the present invention, and FIG. It is side surface sectional drawing which shows the detailed structure of the plunger lower part which shows a moving part.

  4A is a plan view showing a spring receiver according to an embodiment of the present invention. FIG. 4B is a sectional view showing an AA ′ section in FIG. 5A. FIG. 5A is a sectional view showing a pinion according to an embodiment of the present invention. It is a perspective view, (b) It is a perspective view similarly shown from another angle, (c) It is sectional drawing which shows the BB 'cross section of (a).

  6A is a plan view showing an intake hole according to an embodiment of the present invention and a cross-sectional view showing a CC ′ cross section. FIG. 6B is a plan view showing an oil supply hole according to another embodiment of the present invention and a DD ′ cross section. It is sectional drawing shown.

First, the fuel injection pump 10 of the present invention will be briefly described with reference to FIG. As shown in FIG. 1, the fuel injection pump 10 includes a plunger housing 12 that is also formed in a cylindrical shape in a cylindrical pump housing 11, and a plunger in a plunger insertion hole 13 in the plunger barrel 12. 14 is slidably inserted in the vertical direction, and an annular fuel chamber 15 is formed along the outer peripheral surface of the plunger barrel 12 on the inner peripheral surface of the pump housing 11, and the plunger in the plunger insertion hole 13 extends from the fuel chamber 15. A fuel supply port 17 is formed toward the pressurizing chamber 16 at the top of 14, a groove-shaped lead 18 for adjusting the fuel injection amount is formed on the outer periphery of the upper end of the plunger 14, and a flange 21 is formed in the lower middle part. The pinion sleeve 50, which will be described later, is configured to be engageable with a longitudinal groove 53 having a two-surface width . On the other hand, on the plunger sliding surface of the plunger barrel 12, that is, the inner peripheral surface of the plunger insertion hole 13, there is one fuel leak recovery portion 19a communicating with the fuel chamber 15 along the circumferential direction, and fuel leak communicating with the outside. A plurality of recovery portions 19a are formed.

  In the fuel injection pump 10 configured as described above, the plunger 14 slides upward, the top of the plunger 14 closes the fuel supply port 17, pressurizes the fuel in the pressurizing chamber 16, and the isobaric valve 26 above the plunger 14. The fuel can be discharged by being pushed open. When the plunger 14 slides upward from the state in which the fuel is discharged, the lead 18 portion communicates with the fuel supply port 17 and fuel injection ends. Further, the fuel injection pump 10 can adjust the fuel injection amount by changing the communication timing of the lead 18 and the fuel supply port 17 by rotating the plunger 14.

The pinion sleeve 50 is externally fitted to the small diameter portion of the lower end of the plunger barrel 12 so as to be freely rotatable in the circumferential direction, and the upper portion has a pinion 51 (meshing portion) that meshes with the fuel control rack 20 inserted laterally into the pump housing 11. The lower portion is formed with a vertically elongated groove 53 having a two-surface width that engages with the plunger flange 21 (see FIG. 5). The pinion sleeve 50 configured in this manner is configured to rotate the plunger 14 and interlock the fuel injection amount control mechanism by adjustment by sliding of the fuel control rack 20.

  Inside the plunger spring chamber 22, the plunger 14 is urged so as to slide downward between an upper spring receiver 40 fitted on the outer periphery of the pinion sleeve 50 and a lower spring receiver 24 fitted on the plunger guide 23. A plunger spring 25 is interposed. In the plunger spring chamber 22 configured as described above, the cam 14 (not shown) disposed in the crankcase is brought into contact with the tappet (not shown) by the rotational movement of the cam, whereby the plunger 14 and the plunger guide 23 are moved. It is configured to reciprocate up and down to pressurize the fuel in the pressurizing chamber 16 and inject the fuel.

  Here, the internal configuration of the plunger spring chamber 22 according to an embodiment of the present invention will be described with reference to FIG. FIG. 2 shows a state in which the plunger 14 is positioned at the uppermost position in the pump mechanism state. When the plunger 14 is located at the uppermost position, the upper end of the plunger guide 23 is in contact with the upper spring receiver 40 and T inside the plunger spring chamber 22, and the lower end of the plunger barrel 12 and the upper end of the plunger collar 21 are A gap G is formed between them. In other words, the plunger barrel 12 and the plunger collar 21 are not in contact with each other by bringing the plunger guide 23 and the upper spring receiver 40 into contact with each other at the uppermost portion of the plunger 14 in the pump assembly state.

  Conventionally, the lower end of the plunger barrel 12 is in contact with the plunger flange 21 at the uppermost portion of the plunger 14 in the pump-assembled state. At this time, when the lubricating oil is not injected in an appropriate amount and position, the plunger collar 21 may be damaged due to the influence of deposits of low quality oil. As in this embodiment, the plunger barrel 12 and the plunger flange 21 are not in contact with each other at the uppermost portion of the plunger 14 in the pump-worked state, thereby reliably preventing such damage to the plunger flange 21. it can.

  Here, the lubricating oil of the fuel injection pump 10 will be described. When using high-viscosity low-quality oil as fuel, fuel leaks to the sliding surfaces of the plunger barrel 12 and the plunger 14 and adheres to each sliding portion of the fuel injection pump 10 to cause malfunction. There is. Therefore, in order to prevent such low-quality oil from adhering and caking, lubricating oil is injected and each sliding portion is washed.

  Further, referring to FIG. 3, sliding portions (F1 to F4 indicated by bold lines in FIG. 3) that require cleaning with the lubricating oil in the fuel injection pump 10 and paths (L1 indicated by bold arrows in FIG. 3) R2) will be described in detail. Lubricating from the outside of the lubricating oil is performed at the pinion lubricating hole P (see FIGS. 1 to 3). The lubricating oil injected into the fuel injection pump 10 through the pinion lubrication hole P cleans the meshing portion (F1) between the pinion 51 and the control rack 20, flows into the inner periphery of the pinion sleeve 50 (R1), and moves into the plunger barrel 12. And the sliding part (F2) between the pinion sleeve 50 and the plunger flange 21 (F4) are washed and dropped. On the other hand, the lubricating oil that has flowed (R2) into the outer periphery of the pinion sleeve 50 cleans and drops the sliding portion (F3) between the inner periphery of the pump casing 11 and the plunger guide 23. The lubricating oil dripped into the plunger spring chamber 22 is discharged from the fuel injection pump 10 through a discharge hole (not shown). In the following, an embodiment of the present invention configured to allow the lubricating oil to flow into the sliding portion in the fuel injection pump 10 without leakage and to be cleaned will be described.

  First, the shape of the upper spring receiver 40 according to the embodiment of the present invention will be described in detail with reference to FIGS. 4 (a) and 4 (b). The upper spring receiver 40 is a support member that is fitted and fixed to the pump casing 11 in the upper part of the plunger spring chamber 22 and supports the upper end of the spring 25 (see FIGS. 1 to 3). As shown in FIG. 4, the upper spring receiver 40 is formed in a ring shape and has an edge protruding downward from the outer periphery. In the present embodiment, a plurality of notches (41a to 41d) are formed on the outer periphery of the upper spring receiver 40 on the outer sides of the corners at predetermined intervals. The upper surface center side of the notches (41a to 41d) is arranged so as to be located on the inner side of the inner surface of the upper pump casing 11 so that the lubricating oil easily flows. In this embodiment, a total of four semi-circular cutouts (41a to 41d) are formed every 90 degrees in the circumferential direction, but the positions, number, and shapes of the cutouts are described in this embodiment. It is not limited to examples.

  With such a configuration, the lubricating oil dropped on the upper surface of the upper spring receiver 40 is easily guided to the outer periphery of the spring receiver by the notches (41a to 41d) (thick line arrow R2 shown in FIG. 4). Then, a gap (bold arrow R2 shown in FIG. 3) between the outer periphery of the upper spring receiver 40 and the inner periphery of the pump casing 11 is dropped to clean the sliding portion (F3) between the pump casing 11 and the plunger guide 23. Thus, by the notch 41 provided on the outer periphery of the upper spring receiver 40, the lubricating oil is guided to the outer periphery of the plunger guide 23, and the deposit adhering to the outer periphery of the plunger guide 23 can be cleaned. That is, the safety of the fuel injection pump 10 can be improved by preventing the plunger guide 23 from sticking.

  Next, the shape of the pinion sleeve 50 according to the embodiment of the present invention will be described in detail with reference to FIGS. 5 (a) and 5 (b). The pinion sleeve 50 is a rotating member that adjusts the fuel injection amount by engaging with the flange portion 21 of the plunger 14 and rotating integrally. The pinion sleeve 50 includes a cylindrical main body 52 and a pinion 51 formed on the outer periphery of the main body 52. In the lower part of the main body 52, a vertically long groove 53 having a two-sided width opening downward is arranged 180 degrees away from the main body 52, and the main body 52 from the substantially central portion to the lower end is made thick. In the present embodiment, as shown in FIGS. 5A and 5B, at least one lubricating oil intake hole is opened through the outer peripheral surface of the upper and lower middle portion of the main body 52. In other words, at two positions facing each other in the circumferential direction (every 180 degrees), the two intake holes 55 and 56 are opened vertically in the same phase. Further, the lower intake hole 55 is an inclined hole 56 penetrating obliquely downward to the center side. In the present embodiment, the intake holes 57 are formed above the respective widths 53 in the circumferential direction of the main body 52. Although the total number of intake holes for the pinion is 6 holes in this embodiment, it is not limited to this embodiment. In the present embodiment, only the lower intake hole 55 is an inclined hole. However, this is not limited to the present embodiment, and other intake holes (for example, the intake holes 56 and 57) may be used. Even if applied, the following effects can be obtained.

  With such a configuration, as shown in FIG. 5C, even when the lubricating oil that drops on the outer periphery of the main body 52 cannot flow into the inner periphery of the main body 52 through the intake hole 56. The intake hole 55 can flow into the inner periphery of the main body 52 (thick line arrow R3 shown in FIG. 5C). Since the intake hole 55 penetrates diagonally downward, the lubricating oil can flow smoothly. Further, the lubricating oil dripping on the outer periphery of the main body 52 can smoothly flow into the plunger flange portion 21 via the two-side width upper portion at the intake hole 57.

Lubricating oil dropping the pinion sleeve 50 outer periphery by such inclined intake holes 55 are mostly guided in the inner periphery of the pinion sleeve 50, it can be cleaned the deposits attached to the 50 inner circumference pinion sleeve. That is, the safety of the fuel injection pump 10 can be improved by preventing the plunger 14 from sticking. Further, the lubricating oil is guided to the plunger collar 21 from the intake hole 57, and the deposits attached to the plunger collar 21 can be washed. That is, it is possible to prevent damage to the plunge collar 21 by removing the deposits on the plunger collar 21.

  Further, the shapes of the intake holes 60 and 70 according to the embodiment of the present invention will be described in detail with reference to FIGS. 6 (a) and 6 (b). The cross section of the outer opening edge of each of the intake holes 55, 56, and 57 can be an oblique cross section. That is, as illustrated in FIG. 6A, the intake hole 60 forms a chamfered portion 61 by chamfering the edge of the outer peripheral portion (the side into which the lubricating oil flows). On the other hand, as shown in FIG. 6B, the chamfered portion 71 is formed by processing the chamfered area of the upper portion of the intake hole 70 at the edge of the outer peripheral portion (the side into which the lubricating oil flows). The area and angle of the chamfered portions 61 and 71 are not particularly limited in this embodiment. The effects described below can be obtained simply by processing the end face flatly.

  By adopting such a configuration, the dropped lubricating oil is smoothly guided to the intake holes 60 and 70 along the chamfered portions 61 and 71 (thick dashed arrow R4 shown in FIGS. 6A and 6B). It becomes easy to flow into the intake holes 60 and 70. By applying the chamfered intake holes 60, 70 to the intake holes 55, 56, 57 formed in the pinion sleeve 50, the lubricating oil can easily flow into the inner peripheral portion of the pinion sleeve 50, Deposits adhering to the inner periphery of the pinion sleeve 50 can be cleaned. That is, the safety of the fuel injection pump 10 can be improved by preventing the plunger 14 from sticking.

1 is a side sectional view showing an overall configuration of a fuel injection pump according to the present invention. Side surface sectional drawing which shows the detailed structure of the plunger lower part which concerns on the Example of this invention. Side surface sectional drawing which shows the detailed structure of the plunger lower part which shows the sliding part which needs washing | cleaning. (A) Top view which shows the spring receiver which is an Example of this invention (b) Sectional drawing which shows AA 'cross section in (a). (A) The perspective view which shows the pinion which is the Example of this invention (b) The perspective view which shows from another angle similarly (c) Sectional drawing which shows BB 'cross section of (a). (A) A plan view showing an intake hole according to an embodiment of the present invention and a sectional view showing a CC ′ section (b) a plan view showing an oil filling hole according to another embodiment of the present invention and a sectional view showing a DD ′ section .

DESCRIPTION OF SYMBOLS 10 Fuel-injection pump 12 Blanker barrel 14 Blanker 21 collar 23 Blanker guide 25 Spring 40 Upper spring holder 50 Pinion sleeve

Claims (3)

The plunger barrel (12) into which the plunger (14) that slides up and down is inserted, the flange (21) provided in the plunger (14), and the vertically long groove (53) provided in the lower portion, and the plunger barrel A pinion sleeve (50) for externally fitting (12), an upper spring receiver (40) externally fitted to the pinion sleeve (50), and a plunger guide (23) elastically supported by the spring (25) In the fuel injection pump (10) having the above, the upper spring receiver (40) and the upper edge of the plunger guide (23) are in contact with each other at the highest rising position in the vertical reciprocating motion of the plunger (14). and, the aforementioned flange portion (21) configured to be a gap (G) between the Brand Ja barrel bottom, previously plunger guide (23) and receiving an upper spring (40 Contacting the door, the plunger barrel (12) and the flange portion (21) is configured not to contact, characterized by forming at least one notch (41) on the upper end face the outer periphery of receiving the upper spring (40) And fuel injection pump. The fuel injection pump according to claim 1, wherein at least two or more intake holes (55, 56) are provided on an outer peripheral surface of an upper and lower halfway portion of the pinion sleeve (50), and the intake holes (55, 56) are: At least one intake hole is provided above the longitudinal groove (53) provided in the pinion sleeve (50), and the intake hole (55) in the lowest position is directed toward the inner periphery of the pinion sleeve (50). A fuel injection pump characterized in that it is an inclined hole that penetrates obliquely downward . The fuel injection pump according to claim 2, wherein a chamfering process is performed on an outer peripheral side of the intake hole (70), and the chamfering process of the intake hole (70) is made larger on the upper chamfer area than the lower chamfer area. A fuel injection pump characterized by that.