JP3711233B2 - Fuel metering device for diesel engine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a fuel metering device for a diesel engine.
[0002]
[Premise Technology]
The present invention is based on the following technology.
As shown in FIG. 1 or FIG. 3, a fuel injection pump (1) and a mechanical governor (2) are provided. The fuel injection pump (1) is provided with a fuel metering rack (3), and this fuel metering rack (3 ) Includes a rack pin (3a) and is slidably mounted in the fuel increasing / decreasing direction, the mechanical governor (2) includes a governor lever (2a), and the governor lever (2a) has a slider (5 The slider (5) is slidably attached in the fuel increasing / decreasing direction, and is urged by the urging spring (S) in the fuel increasing / decreasing direction. A fuel metering device for a diesel engine, in which a rack pin (3a) is inserted into a gap (6) between each facing surface (5a) (4a) with (4).
[0003]
[Prior art]
Conventionally, as a fuel metering device for a diesel engine, in the base technology, a rack pin is sandwiched between the opposing surfaces of the slider and the swinging end portion of the governor lever by a biasing force of a biasing spring.
[0004]
[Problems to be solved by the invention]
The above prior art has the following problems.
As the governor lever swings, the outer peripheral surface of the rack pin and the opposing surfaces rub against each other while receiving contact pressure by the urging force of the urging spring, and these wear gradually. In this case, the fuel metering rack gradually shifts to the fuel increase side, and the fuel injection amount becomes excessive. This is a factor that decreases the fuel metering accuracy and increases the concentration of harmful components in the exhaust gas.
[0005]
The subject of this invention is providing the fuel metering apparatus of the diesel engine which can solve the said problem.
[0006]
[Means for Solving the Problems]
(Invention of Claim 1)
As shown in FIG. 1, in the base technology, the governor lever (2a) is provided with a stopper (7), and the slider (5) is received by the stopper (7), whereby the dimension (L1) of the gap (6). Is maintained larger than the outer diameter dimension (L2) of the rack pin ( 3a ) , and the rack pin ( 3a ) is loosely fitted in the gap ( 6 ) .
[0007]
(Invention of Claim 2)
As shown in FIG. 3, in the base technology, the slider (5) includes a stopper (8), and the stopper (8) is received by the swinging end (4) of the governor lever (2). Diesel characterized in that the dimension (L1) of (6) is kept larger than the outer diameter dimension (L2) of the rack pin ( 3a ) , and the rack pin ( 3a ) is loosely fitted in the gap ( 6 ) . Engine fuel metering device.
[0008]
[Action and effect of the invention]
The inventions of claims 1 and 2 both have the following effects.
As shown in FIG. 1 or FIG. 3, even when the governor lever (2a) swings, only the outer peripheral surface of the rack pin (3a) and one of the opposing surfaces (5a) (4a) rub against each other, and rub against each other. Since the contact pressure due to the urging force (Sa) of the urging spring (S) is not applied to the surface, wear caused by this is prevented. When this wear occurs, the fuel metering rack (3) gradually shifts to the fuel increase side, and the fuel injection amount becomes excessive. However, since this problem does not occur, the fuel metering accuracy is properly maintained, Further, an increase in the concentration of harmful components in the exhaust gas is also suppressed.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described with reference to the drawings. 1 and 2 are diagrams for explaining a first embodiment of the present invention. In this embodiment, a fuel metering device for a vertical multi-cylinder diesel engine is used.
[0010]
The configuration of this fuel metering device is as follows.
As shown in FIGS. 1 and 2, the apparatus includes a fuel injection pump (1) and a mechanical governor (2). These are all housed in the injection pump housing case (10). The fuel injection pump (1) includes a fuel metering rack (3). The fuel metering rack (3) includes a rack pin (3a) and is slidably attached in the fuel increasing / decreasing direction. In the fuel metering rack (3), the output portion (18a) of the engine stop solenoid (18) faces the end portion on the fuel increase side.
[0011]
The configuration of the mechanical governor (2) is as follows.
The mechanical governor (2) includes a first governor lever (2a), a second governor lever (2b), and a third governor lever (2c). These governor levers (2a), (2b) and (2c) are all pivotally supported by the governor lever shaft (9). The governor lever shaft (9) is installed in the injection pump housing case (10). The first governor lever (2a) is provided with a governor force input portion (13) at the lower oscillating end thereof, which faces the governor sleeve (21), and this governor sleeve (21) faces the governor weight (14). It is out.
[0012]
Second governor lever (2b) are faces from the fuel reduction side in the first governor lever (2a), it is interlocked to the governor lever through the governor spring (16) (17). The second governor lever (2b) is provided with a contact portion (11) at the upper oscillating end thereof, and this is exposed to the fuel limit bolt (12) from the fuel reduction side. The third governor lever (2c) is disposed between the first governor lever (2a) and the second governor lever (2b), and includes a torque riser (15) at the upper swing end thereof. A torque rise spring (not shown) is accommodated in the torque rise device (15). Although not shown, the third governor lever (2c) is provided with a torque rise limiting bolt from the fuel increase side, and is attached so as to be able to advance and retract from the outside of the injection pump housing case (10).
[0013]
The first governor lever ( 2a ) is provided with a slider (5) at its upper swing end (4), and the slider (5) is slidably attached in the fuel increasing / decreasing direction, and the urging spring in the fuel increasing direction. It is energized in (S). A rack pin (3a) is inserted into a gap (6) between the facing surfaces (5a) (4a) of the slider (5) and the swing end (4) of the first governor lever (2a).
[0014]
The function of the mechanical governor (2) is as follows.
During engine operation, the governor levers (2a), (2b) and (2c) swing together as a result of the unbalanced force of the governor spring force (16a), the governor force (14a) and the biasing spring force (Sa). The fuel metering rack (3) is metered and moved. When the engine load exceeds the rated load, the second governor lever (2b) is received by the fuel limiting bolt (12), and the governor force (14a), bias spring force (Sa), and torque rise spring force (not shown) The unbalanced force causes the first governor lever (2a) and the third governor lever (2c) to swing together to move the fuel metering rack (3) by metering, and suppresses engine stall by torque rise. The maximum fuel injection amount of the torque rise can be adjusted from the outside of the injection pump housing case (10) by a torque rise limiting bolt.
[0015]
When the engine is stopped, the fuel metering rack (3) is pushed to the fuel reduction side by the engine stop solenoid (18). In this case, since the fuel metering rack (3) can move to the fuel non-injection position while pushing the slider (5) with the rack pin (3a), the fuel metering rack (3) has a resistance of the governor spring force (16a). However, only the resistance of the biasing spring force (Sa) smaller than the governor spring force (16a) is applied. For this reason, the engine stop solenoid (18) may be a small and small output. Since no governor force (14a) is generated when the engine is started, the fuel metering rack (3) is pulled to the fuel increasing side together with the first governor lever (2a) by the biasing spring force (Sa). It is located at the start increasing position beyond the limit position of torque rise, and the startability is improved.
[0016]
In this embodiment, the following device is made.
The first governor lever (2a) includes a stopper (7), and the slider (5) is received by the stopper (7), so that the dimension (L1) of the gap (6) is the outer diameter dimension (L2) of the rack pin (3a). The rack pin ( 3a ) is loosely fitted in the gap ( 6 ) . For this reason, even if the first governor lever (2a) swings, only the outer peripheral surface of the rack pin (3a) and one of the opposing surfaces (5a) (4a) rub against each other, and the rubbed surface is energized. Since the contact pressure due to the biasing force (Sa) of the spring (S) is not applied, wear caused by this is prevented. The stopper (7) protrudes from the opposed surface (4a) of the swing end (4) of the first governor lever (2a) toward the opposed surface (5a) of the slider (5). In FIG. 1A, reference numeral (19) denotes a high idle spring, and (20) denotes a contact portion thereof. The contact portion (20) is integrally formed with the slider (5).
[0017]
In the second embodiment shown in FIGS. 3 and 4, the slider (5) includes a stopper (8), and the stopper (8) is received by the swinging end (4) of the governor lever (2). The dimension (L1) of the gap (6) is held larger than the outer diameter dimension (L2) of the rack pin (3a). Other configurations and functions are the same as those in the first embodiment. In FIG. 3 and FIG. 4, the same reference numerals are given to the same elements as those in the first embodiment.
[0018]
In addition, this invention is not limited to said each embodiment, For example, it is needless to say that the thing provided with the two lever type governor without the 3rd governor lever (2c) is applicable.
[Brief description of the drawings]
FIG. 1 is a view for explaining a fuel metering device for a diesel engine according to a first embodiment of the present invention, in which FIG. 1 (A) is a longitudinal side view, and FIG. 1 (B) is a swing end portion of a first governor lever. FIG. 5 is a view of the slider and the slider as viewed from the fuel injection pump side.
FIG. 2 is a longitudinal front view of the apparatus of FIG.
FIG. 3 is a view corresponding to FIG. 1 of a second embodiment of the present invention.
4 is a view corresponding to FIG. 2 of the apparatus of FIG. 3;
[Explanation of symbols]
(1) ... fuel injection pump, (2) ... mechanical governor, (2a) ... first governor lever, (3) ... fuel metering rack, (3a) ... rack pin, (L2) ... outer diameter, (4) ... The swing end of the first governor lever, (4a) ... facing surface, (5) ... slider, (5a) ... facing surface, (S) ... biasing spring, (6) ... gap, (L1) ... dimensions, ( 7) (8) ... Stopper.

Claims (2)

A fuel injection pump (1) and a mechanical governor (2) are provided. The fuel injection pump (1) includes a fuel metering rack (3). The fuel metering rack (3) includes a rack pin (3a). The mechanical governor (2) is provided with a governor lever (2a), and the governor lever (2a) is provided with a slider (5) at its swing end (4). It is slidably mounted in the fuel increasing / decreasing direction, and is urged by the urging spring (S) in the fuel increasing direction. In a fuel metering device for a diesel engine, in which a rack pin (3a) is inserted into a gap (6) between (4a),
The governor lever (2a) includes a stopper (7), and the slider (5) is received by the stopper (7), so that the dimension (L1) of the gap (6) is the outer diameter dimension (L2) of the rack pin (3a). Is kept larger than
A fuel metering device for a diesel engine, wherein a rack pin (3a) is loosely fitted in the gap (6). A fuel injection pump (1) and a mechanical governor (2) are provided. The fuel injection pump (1) includes a fuel metering rack (3). The fuel metering rack (3) includes a rack pin (3a). The mechanical governor (2) is provided with a governor lever (2a), and the governor lever (2a) is provided with a slider (5) at its swing end (4). It is slidably mounted in the fuel increasing / decreasing direction, and is urged by the urging spring (S) in the fuel increasing direction. In a fuel metering device for a diesel engine, in which a rack pin (3a) is inserted into a gap (6) between (4a),
The slider (5) includes a stopper (8). The stopper (8) is received by the swing end (4) of the governor lever (2), so that the dimension (L1) of the gap (6) is changed to the rack pin (3a). ) Larger than the outer diameter dimension (L2) of
A fuel metering device for a diesel engine, wherein a rack pin (3a) is loosely fitted in the gap (6).

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