JPH0454045B2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field]

The present invention is a control device for a fuel injection pump of an internal combustion engine, and is provided with a casing that is in contact with a casing of the fuel injection pump and accommodates an adjustment mechanism, and the adjustment mechanism is configured to control the fuel injection pump relative to the adjustment mechanism casing. A suction pump is provided at the bottom of the adjustment mechanism casing for operating the fuel injection pump adjustment member protruding into the adjustment mechanism casing through the wall separating the injection pump, and for sucking out liquid that has entered the adjustment mechanism casing from the fuel injection pump. Relates to the format provided in the range.

[Conventional technology]

For fuel injection pumps and their speed governors, forced lubrication systems that do not require maintenance are currently widely used, and the fuel injection pumps are connected to the lubricating oil circuit of the internal combustion engine. The fuel injection pump must be sealed as completely as possible to prevent lubricating oil from leaking to the outside. Sealing where the camshafts driving the individual pump pistons protrude from the pump casing is not very difficult. This means that the camshaft bearing can be sealed satisfactorily. However, the adjustment member (adjustment rod) that adjusts the discharge amount of the fuel injection pump also protrudes from inside the fuel injection pump through the guide and into the adjustment mechanism casing, and this location must be sealed to prevent lubricant from leaking. That is practically impossible. This is because the adjustment rod must be able to move easily without getting caught during guidance. The adjustment rod becomes difficult to move or becomes stuck, which impedes the adjustment action and makes the adjustment action unstable. Through this necessary guiding play, lubricating oil therefore leaks into the adjusting mechanism housing, and the oil level gradually rises in the adjusting mechanism housing. In particular, if the fuel injection pump is extremely tilted, there is a risk that the regulating mechanism will be immersed in this leaked lubricating oil, impairing its function or rendering it completely inoperable. Therefore, it has already been proposed to provide a suction pump within the regulating mechanism casing, as described, for example, in Japanese Patent Application Laid-Open No. 56-88936. However, in the case of JP-A-56-88936, the liquid in the regulating mechanism casing is drawn into the intake pipe by means of a negative pressure in the vent lily portion of the intake pipe using a long conduit and is combusted in the cylinder. Burning lubricating oil in the cylinder makes, for example, fuel control of the internal combustion engine uncertain, and is not desirable.

[Problem to be solved by the invention]

It is an object of the present invention to provide a suction pump capable of dispensing liquid (lubricating oil) without the need for long conduits or hoses.
is sent back into the fuel injection pump, which is its original place of use, and the suction pump is designed to be as simple and inexpensive as possible.

[Means and actions for solving the problem]

In order to solve this problem, according to the present invention,
In a control device for a fuel injection pump of an internal combustion engine of the aforementioned type, the extension of the drive shaft of the fuel injection pump projects into the regulating housing and has a rotating member thereon, which rotates the suction As part of the pump, it projects into the bottom region of the regulator casing, which receives the infiltrating liquid, and the suction pump is adapted to pump the liquid in the regulator casing back into the interior of the housing of the fuel injection pump. With this arrangement according to the invention, the lubricating oil is returned to the interior of the fuel injection pump casing without the need for long conduits or hoses. Further, since the suction pump is driven by the originally existing fuel injection pump drive shaft, the suction pump does not require its own drive shaft and can be easily constructed. In the case of electric control devices, the camshaft of the internal combustion engine (fuel injection pump drive shaft) has a pulse wheel in its extension projecting into the regulating housing in order to detect the drive speed. This pulse wheel is used as a rotating member, that is, as part of a suction pump.
This further simplifies the structure of the suction pump. In the embodiments according to claims 2 to 4, the construction of the suction pump is particularly simple and inexpensive. The contact surfaces of the rotary member and the stationary flat member, which slide relative to each other, are in continuous contact with lubricating oil, and this lubrication action prevents significant wear. By crimping the sliding shoe with a crimping spring, for example a cylindrical coil spring, an adjustable and predetermined crimping force can be applied and the actuation of the suction pump can be adjusted automatically as a function of the rotational speed, so that the suction Pressure is automatically limited. That is,
If the suction pressure (conveying pressure) becomes excessively large, for example due to an excessively high rotational speed of the rotating member, the product of the pressure and the effective area will become larger than the crimping force, causing the sliding force of the crimping spring. It overcomes the pressing force and is pushed away from the rotating member. The embodiments of claims 5 to 9 also provide a more advantageous structure of the suction device. The check valve prevents liquid (lubricating oil) from flowing back when the suction pump is stopped. Furthermore, the suction pump will be an automatic suction type. The embodiment of claim 10 is particularly advantageous in that when the injection pump is stopped, the lubricating oil is removed due to the incomplete sealing of the suction pump, in particular its non-return valve or discharge conduit. Access from the injection pump into the regulating housing is prevented. Furthermore, in the embodiments according to claims 11 to 14, the suction pump is constructed particularly inexpensively and simply, and its assembly is simple. The embodiment of patent claim 15 is further particularly advantageous. Such an integral sliding shoe is extremely simple and inexpensive. The gap does not necessarily have to be wedge-shaped, and it is sufficient that the depth remains constant, for example, 0.3 to 0.5 mm, so this integrated sliding shoe can be made particularly flat and thin as a trapezoidal member at low cost. It can be configured with an extremely small space requirement. The compression spring is preferably arranged approximately in the center of the gap and centered, for example, by a circular centering projection.

【Example】

The configuration of the present invention will be specifically explained below based on the drawings. A housing 12 of an adjusting mechanism 11 is mounted on a fuel injection pump 10, which is shown only schematically in FIG. Since the structure of the fuel injection pump 10 is well known, detailed explanation will be omitted here. In a conventional manner, the fuel injection pump 10 has an adjusting rod 8 which projects from its housing 13 through an adjusting rod guide 7 for adjusting the fuel delivery, which adjusting rod 8 is connected to the housing 12 of the adjusting mechanism 11. It is operated by an adjustment magnet 9 (shown schematically) located inside the . Adjustment rod 8 is adjustment guide 7
It is designed to be able to be moved easily and without play as much as possible. This allows for light adjustment movements. If the adjustment rod 8 becomes difficult to move or becomes stuck, the adjustment action will be hindered and the adjustment action will become unstable. Usually, a fuel injection pump is connected to a lubricating oil circuit of an internal combustion engine in order to lubricate its components, such as the camshaft 14 for driving the pump piston, and lubricating oil is present inside the casing 13. . In contrast, the interior 16 of the housing 12 of the adjusting mechanism 11 must be sealed. For this purpose, the camshaft bearing 17 provided in the housing 13 is sealed in the usual manner. However, through the aforementioned adjustment rod guide 7 between the fuel injection pump 10 and the adjustment mechanism 11, lubricating oil enters the interior 16 of the casing 12, even if only in a small amount, so that the oil level gradually rises. . Practice has shown that starting is difficult when the fuel injection pump is stopped at an extreme incline to cool down and the adjusting magnet 9 is submerged in lubricating oil. There is. This is because in this case the adjusting force of the adjusting magnet 9 is too small and the adjusting rod 8 cannot be actuated quickly enough. According to the present invention, in order to prevent the adjusting magnet 9 from being soaked in lubricating oil even in an extremely inclined state,
A suction device 18 is arranged inside the casing 12 of the adjustment mechanism 11, and this suction device drains lubricating oil leaking from the fuel injection pump 10 into the casing 1.
2 and sent back into the interior 15 of the fuel injection pump 10. The suction device 18 has a suction pump 19 , which is connected on the suction side to a region 20 near the bottom of the interior 16 of the housing 12 and on the discharge side to the casing 13 of the fuel injection pump 10 .
It is connected to the inside 15 of the. The suction pump 19 is driven by the camshaft 14 of the fuel injection pump 10. The camshaft 14 thus has a rotating member which serves as a pulse wheel 21 of the rotational speed signal generator, which at least has a circumferential section 22 near the bottom.
into the oil sump 23 containing the lubricating oil. The direction of rotation of pulse wheel 21 is indicated by arrow 24 in FIG. The suction device 18 extends into the sump 23 in the area of the circumferential section 22, also in the lowermost area,
It has a gap 25 between the back surface 26 of the pulse wheel 21 and the fixed flat member 27.
It is formed and partitioned by. The gap 25 tapers gradually from the open end towards the tapered end 29 in the direction of rotation of the pulse wheel 21 (arrow 24), like the well-known lubricating wedge in thrust bearings (see FIG. 3). . The flat element 27 arranged at the rear side of the pulse wheel 21 is constructed as a sliding shoe and consists of two sliding shoe parts 31 and 32 which are connected to each other, for example by adhesive, and are crimped onto the rear side 26. It is crimped by a spring 30. The two sliding shoe parts 31 and 32 have the same shape and size and are designed, for example, in the form of ring segments. In this case, the aforementioned gap 25 is formed in the sliding shoe part 31 on the side of the pulse wheel 21, for which purpose the sliding shoe part 31 has a contact surface 33 which cooperates with the back side 26 of the pulse wheel 21.
It has a generally groove-like recess of U-shaped cross section, the depth of which decreases in a wedge-shaped manner from the open end 28 to the tapered end 29. Tapered end 29
In the area of the opening 25 opens into a transversely large cross-section pocket 34, which itself is connected to an axis-parallel discharge channel 35. The two sliding shoe parts 31, 32 are rigidly connected to each other in a direction perpendicular to the rear surface 26;
It is movably guided in this direction by the casing 13. For this purpose, one sliding shoe part 32 has at least one guide pin 36 on the rear side facing away from the pulse wheel 21, which engages in a guide hole formed in the housing 13. There is. A hose fitting 38 for a discharge hose 39 is provided adjacent to the guide pin 36;
The discharge hose 39 passes through a hole 40 formed in the casing 13 and communicates with the interior 15 of the casing 13 . The sliding shoe part 32 has a collecting chamber 41 as a recess on the side facing the pulse wheel 21 , and this collecting chamber 41 is formed by the sliding shoe part 31 .
It is connected to a discharge passage 35 formed in the discharge hose 3 through a hose joint 38.
Connected to 9. The suction device 18 includes at least one check valve 50
This check valve 50 has a casing 1
Only the flow of lubricating oil from the interior 16 of casing 2 to the interior 15 of casing 13 is allowed, and flow in the opposite direction is blocked. That is, the check valve 50 is located on the discharge side of the suction device 18 and opens toward the interior 15 of the casing 13. In the exemplary embodiment shown, the check valve 50 is arranged inside the two-part sliding shoe 31, 32 and is designed as a plate valve. The non-return valve 50 thus has a valve plate 51 which is located between the two sliding shoe parts 32 and which connects the discharge passage 35 of the sliding shoe part 31 to the collection chamber 41 of the sliding shoe part 32. control the opening of the Valve plate 51 is attached to the back of sliding shoe portion 31 by pins 52. This rear surface is designed approximately in the shape of a hook in the area of the opening of the discharge channel 35 and forms an annular sealing surface 53 for the valve plate 51 . A fuel injection pump 10 is installed inside 16 of the adjustment mechanism 11.
The lubricating oil that entered from the casing 13 of the camshaft 1
It is entrained in the direction of rotation (arrow 24) by a pulse wheel 21 driven by 4. it is,
This is because the lubricating oil adheres to the pulse wheel 21. The lubricating oil reaches the interior of the gap 25 and collects in the pocket 34. A pressure is created in the gap 25 which pushes the valve plate 51 away from the sealing surface 53 and directs the lubricating oil from the discharge passage 35 into the collection chamber 41 of the sliding shoe part 32. The lubricating oil returns to the interior 15 of the fuel injection pump 10 via the hose fitting 38 and the exhaust hose 39. For example, if the rotation speed of the camshaft 14 is excessively high and the conveying pressure becomes excessively large, the product of the oil pressure in the gap 25 and the working surface becomes larger than the pressing force of the pressing spring 30 acting in the direction of the arrow 42. At this time, the flat member 27 is pushed away from the back surface 26 of the pulse wheel 21 against the action of the compression spring 30. Advantageously, both sliding shoe parts 31, 32 are made of plastic. The suction device 18 is suitable for small conveying volumes and pressures. This suction device 18 has a simple structure and is extremely inexpensive. Apart from the pulse wheel 21, the suction device itself has no moving parts, so wear is negligible. Also check valve 50
The structure is extremely simple, works reliably, and is inexpensive. Therefore, the lubricating oil collected in the gap 25 can be pushed out by simple means,
At the same time, reliable sealing is achieved. Suction device 1
8, even if the fuel injection pump 10 is extremely tilted,
The adjustment magnet 9 in the interior 16 of the adjustment mechanism 11 is immersed in lubricating oil to reliably prevent starting difficulties. Slide the sliding show parts 31 and 32 with the pulse wheel 2
The arrangement on the rear side 26 of 1 requires particularly little space and does not make the electrical control device expensive. Of course, the sliding show part 31,
The outer surface of the rotating member that cooperates with 32 may be a circumferential surface. In this case, the sliding shoe and the gap should be curved accordingly. In the second embodiment shown in FIGS. 4 to 6,
The same parts as in the first embodiment are given numerals incremented by 100. The discharge side of the suction device 118 is a camshaft bearing 117
The fuel injection pump 11 is located at a distance above the
It opens into the interior 115 of 0. A hole 140 is formed in the casing 113 at this opening, and a discharge hose 139 extends from the flat member 127 around the camshaft 114 in an arc shape to reach the hole 140. In this case, the discharge hose 139 is fixed to the casing 113 by a catch 160. The exhaust hose 139 is made of resilient, heat resistant plastic. Discharge hose 13
A connecting plug 161 is fitted at the end of 9, which is constructed as a plastic molding and is fixed to the discharge hose 139, for example by gluing. The connection plug 161 has a large number of annular grooves 162 on the outer peripheral surface, and the hole 14
0, in this case the annular groove 1
62 cooperates with the surface of hole 140 to form a labyrinth seal. The non-return valve 150 is located in the area of the opening and is designed as a mushroom-shaped rubber valve 154 and has a hole plate 155 with a retaining pin 156 and an elastic valve body 157 made of rubber. Valve body 15
7 is attached to a holding pin 156. Valve body 15
7 covers the hole in the hole plate 155 from the left side as seen in FIG. When pressure is applied to the valve body 157 from the right side as viewed in FIG. 4, the valve body opens the hole in the hole plate 155. The hole plate 155 is the annular groove 15 of the connection plug 161.
8 and fixed, for example by gluing. An intermediate chamber 15 is formed in the connecting plug 161 between the free end of the discharge hose 139 and the hole plate 155.
9 is formed for lubricating oil. The connection plug 161 is attached to the stepped surface 163 of the casing 113 from the right side as seen in FIG.
64 in the axial direction. Crimp spring 1 supported by casing 113
Back side 126 of pulse wheel 121 by 30
In contrast to the first embodiment, the flat element 127, which is pressed in a resilient manner, is a one-piece sliding shoe 170 which is constructed as a plastic molding and has an approximately trapezoidal shape. sliding show 1
70 has a gap 125 of U-shaped cross section on its contact surface 133. Unlike the case of the first embodiment, this gap 125 has a constant depth and is not wedge-shaped. In this case, for example 0.3mm~
A depth of about 0.5 mm is sufficient. Open end 12
At the end 129 on the side opposite to 8, there is a sliding shoe 17.
0 has a hole 171 into which a generally L-shaped plastic hose fitting 172 is inserted and fixed by adhesive. Hose fitting 17
2 is a discharge passage 135 communicating with the gap 125
The lower end of the discharge hose 139 as viewed in FIG. 4 is connected to this hose joint 172. A one-piece trapezoidal sliding shoe 170 is inserted with its two corners 176 into two guide pockets 177, which guide the sliding shoe 1.
70 forms a sliding guide. The compression spring 130 is centered by the centering projection 173 in the center plane of symmetry between the two corners 176. On the other side, the casing 113 is provided with a centering pin 174, which is connected to the hole 1.
It is inserted into 75. As in the first embodiment, the sliding shoe 170
The pocket 13 is located at the end 129 of the gap 125.
4 (indicated by a chain line).

【Effect of the invention】

The present invention achieves the following remarkable effects by virtue of the configuration described above. Firstly, there is no need for long conduits or hoses that extend from the bottom region of the regulating housing to the vent ridge of the intake pipe. Moreover, the sucked lubricating oil is not burned in the cylinder, but is directly sent back to the fuel injection pump itself, where it is originally used. Furthermore, the suction pump is driven by the drive shaft of the fuel injection pump, so the structure is extremely simple and inexpensive.

[Brief explanation of drawings]

FIG. 1 is a schematic partial sectional view of the first embodiment;
The figure is an exploded perspective view of a part of Figure 1, and Figure 3 is a partial exploded perspective view of Figure 1.
FIG. 4 is a schematic cross-sectional view of the second embodiment taken along the line - in FIG. 5; FIG. figure,
FIG. 6 is a sectional view of the sliding shoe taken along the line - in FIG. 5. 7... Adjustment rod guide, 8... Adjustment rod, 9... Adjustment magnet, 10... Fuel injection pump, 11... Adjustment mechanism, 12 and 13... Casing, 14... Camshaft, 15 and 16... Internal, 17...Camshaft bearing, 18...Suction device, 19...Suction pump, 2
0... Range, 21... Pulse wheel, 22...
Circumference division, 23...Oil sump, 24...Arrow, 25
...Gap, 26...Back surface, 27...Flat member,
28...Open end, 29...Tapered end, 30...
Crimp springs, 31 and 32...Sliding shoe portion, 3
3... Contact surface, 34... Pocket, 35... Discharge passage, 36... Guide pin, 38... Hose joint,
39... Discharge hose, 40... Hole, 41... Gathering room, 42... Arrow, 50... Check valve, 51...
Valve plate, 52... Pin, 53... Seal surface, 129
... End part, 154 ... Mushroom-shaped rubber valve, 155 ...
...hole plate, 156...retaining pin, 157...valve body,
158... Annular groove, 159... Intermediate chamber, 160...
... Clasp, 161 ... Connection plug, 162 ... Annular groove, 163 ... Step surface, 164 ... Spring ring, 1
70...sliding show, 171...hole, 172...
Hose joint, 173... Centering protrusion, 174...
Centering pin, 175...hole, 176...corner, 1
77...Information pocket.

Claims (1)

[Scope of Claims] 1. A control device for a fuel injection pump 10, 110 of an internal combustion engine, which is provided with a casing 12 that accommodates an adjustment mechanism 11 in contact with a casing 13, 113 of the fuel injection pump. Adjustment mechanism 11
passes through the wall separating the fuel injection pump from the adjustment mechanism casing 12 and connects the adjustment mechanism casing 1 to the adjustment mechanism casing 12.
A suction pump is provided in the bottom region 20 of the adjustment mechanism casing 12 for actuating the fuel injection pump adjustment member projecting into the adjustment mechanism casing 2 and for sucking out the liquid that has entered the adjustment mechanism casing 12 from the fuel injection pump. In this case, an extension of the drive shaft of the fuel injection pump protrudes into the regulating housing 12 and has a rotating member there, which rotates the regulating housing 12 as part of the suction pump. The suction pump projects into the bottom region 20 which receives the liquid, and the suction pump transfers the liquid in the regulator housing to the housing 13 of the fuel injection pump.
Control device for a fuel injection pump of an internal combustion engine, characterized in that it sends back to the interior 15, 115 of 13. 2. A flat member 27 is in contact with the outer surface of the rotating member, and this flat member has a bag-shaped recess that is in contact with the outer surface of the rotating member and is open in a direction opposite to the direction of rotation of the rotating member. , this recess is the discharge passage 3
Casing 13 of fuel injection pump 10 via 5
Claim 1 connected to the interior 15 of
The control device described in Section. 3. Control device according to claim 2, in which the recess has a U-shaped cross section. 4. The flat element 27 is constructed as a sliding shoe and is movably guided approximately at right angles to the rear surface 26 of the rotary member and is pressed onto the rear surface 26 of the rotary member by means of a pressure spring 30. A control device according to scope 2. 5 The suction pump has at least one check valve 50
According to claim 4, the check valve is disposed on the discharge side of the suction pump and is configured to open toward the interior 15 of the casing 13 of the fuel injection pump 10. control device. 6. According to claim 5, the check valve 50 is arranged between the recess of the flat member and the discharge conduit connecting the recess to the interior 15 of the casing 13 of the fuel injection pump 10. Control device as described. 7. The control device according to claim 5, wherein the check valve 50 is arranged at or within the sliding shoe. 8. A control device according to claim 2, wherein the depth of the recess decreases approximately wedge-shaped in the direction of rotation of the rotary member, and a discharge passage 35 is provided at its tapered end. 9. A control device according to claim 8, in which the tapered end 29 of the recess opens into a pocket 34 of large cross-section, which pocket itself is connected to a discharge passage 35. 10. The discharge side of the suction pump opens into the interior 115 of the casing 113 of the fuel injection pump 110 at a distance above the camshaft bearing 117 of the fuel injection pump 110. Control device. 11. Control device according to claim 10, characterized in that a check valve (150) is arranged at the point where the discharge conduit opens into the interior (115) of the casing (113) of the fuel injection pump (110). 12. Control device according to claim 11, characterized in that the discharge conduit is configured as a hose or a tube extending from the flat element 127 to the opening into the interior 115 of the casing 113 of the fuel injection pump 110. 13 The discharge conduit has at its open end into the interior 115 of the casing 113 of the fuel injection pump 110 a connecting plug 161 which fits tightly into the hole 140 formed in the fuel injection pump casing 113. 12. A control device according to claim 11 inserted therein. 14 The connection plug 161 is connected to the free end of the hole plate 15.
5 and an elastic valve body 157 held therein as a mushroom-shaped rubber valve 154 as a check valve 150.
The control device according to claim 13, having as follows. 15. The flat element 127 is constructed as an approximately trapezoidal one-piece sliding shoe 170 and has a recessed gap 125 in its contact surface 133 for the rotary element, the side of this gap opposite the open end 128 11. A control device as claimed in claim 10, in which a fitting is provided for the discharge conduit, at the end of which has a discharge passage 135. 16. The control device according to claim 15, wherein the depth of the gap 125 remains constant in the rotational direction of the rotating member.