JPH0539734A - Electronic-mechanical type complex speed regulator - Google Patents

Abstract

PURPOSE:To selectively transfer control action of either one of an electronic speed regulator and a mechanical speed regulator to a fuel control rack rod according to an operating condition of an engine or an abnormal situation by connecting the regulators which function independently. CONSTITUTION:A control rod 21 driven by an electronic speed regulator 2 and another control rod 31 driven by a mechanical speed regulator are arranged parallel to a fuel control rack rod 11 for a fuel injection pump 1 and movably in the axial direction. The control rods 21, 31 are connected to each other via a guide link 41. One end of a switch link 47 is connected to the fuel control rack rod 11 while the other end thereof is slidably fitted into a slot 41a formed in the guide link 41. A pin 48 connected to the switch link 47 is inserted into another slot 49a of a guide rod 49 parallel to the fuel control rack rod 11. The guide rod 49 is moved parallel in the direction perpendicular to the fuel control rack rod 11 by an actuator 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a speed governor for a fuel injection pump for a diesel engine, and more particularly to an electronic / mechanical combined speed governor capable of switching between two types of speed governors in preparation for operating conditions and failures. ..

[0002]

2. Description of the Related Art A diesel engine for a vehicle equipped with an electronic speed governor, when the control is disturbed due to an electrical failure or a radio interference,
Smooth operation of the vehicle is hindered. For this reason, electronic speed governors are equipped with various types of main components such as various sensors, conductors (harness), and control devices, and when one malfunctions, the other operates. It is hard to say that it works effectively against.

Therefore, in the electronic / mechanical composite speed governor disclosed in Japanese Patent Application Laid-Open No. 60-85225, an electronic speed governor is connected in series to a mechanical speed governor, and the mechanical speed governor is used. Simultaneous control is performed, and at the same time fine control is performed within a limited range by the electronic speed governor, and if the electronic speed governor fails, the mechanical speed governor can continue the operation of the engine. .. However, in the electronic / mechanical composite speed governor described above, the mechanical speed governor and the electronic speed governor are connected in series, and the control operation amounts of both are added and transmitted to the fuel control rack rod. The conventional electronic speed governor functioning as a single unit and the mechanical speed governor cannot be established simply by connecting them, and the control contents of the conventional electronic speed governor and the dimensions of the link of the mechanical speed governor are not established. Need to be changed, which incurs a cost burden.

[0004]

SUMMARY OF THE INVENTION In view of the above problems, the object of the present invention is to connect the conventional electronic speed governor and mechanical speed governor as they are, depending on the operating conditions of the engine and abnormal situations. An object of the present invention is to provide an electronic / mechanical composite speed governor for selectively transmitting the control operation of one of the speed governors to the fuel control rack rod.

[0005]

To achieve the above object, the structure of the present invention comprises a first control rod driven by an electronic speed governor and a second control rod driven by a mechanical speed governor. The control rod and the fuel control rack rod of the fuel injection pump are arranged in parallel with each other, the first control rod and the second control rod are connected by a guide link, and one end is connected to the fuel control rod rod. Of the guide rod is slidably engaged with the elongated hole of the guide link, the pin connected to the switching link is engaged with the elongated hole of the guide rod parallel to the fuel control rack rod, and the guide rod is connected with the fuel control rack rod. It is equipped with an actuator that translates in a perpendicular direction.

[0006]

According to the present invention, the electronic speed governor and the mechanical speed governor are selectively connected to the fuel control rack rod through the switching link mechanism. That is, when the electronic speed governor is connected to the fuel control rack rod, the control operation of the conventional electronic speed governor functioning as a single unit is transmitted to the fuel control rack rod. When the electronic speed governor has an electrical failure, the switching link mechanism is automatically driven by the actuator based on the stop of the signal from the electronic control unit, and the mechanical speed governor is connected to the fuel control rack rod. .. The control operation of the conventional mechanical speed governor that functions alone is transmitted to the fuel control rack, and the abnormal operation of the electronic speed governor is not transmitted.

[0007]

1 is a side view showing a schematic structure of an electronic / mechanical composite speed governor according to the present invention. A known fuel injection pump 1 supports a fuel control rack rod 11 that controls an injection amount by a bearing 13 so as to be slidable in an axial direction, and the fuel control rack rod 11 is projected rightward from an end wall of a pump body. .. A case 4 that accommodates the switching link mechanism 6 is connected to the end wall of the pump body. A known electronic speed governor 2 and a mechanical speed governor 3 are connected to the end of the case 4. Electronic speed governor 2
The control rod 21 of the electromagnetic actuator controlled by the electronic control unit 24 projects into the case 4 and is supported by the bearing 22 so as to be movable in the axial direction.

A rack sensor 25 for detecting the operation amount of the control rod 21 and a rotation speed sensor 26 for detecting the engine speed.
And signals from an accelerator sensor 23a that detects the amount of depression of the accelerator pedal 23, and further signals from a load sensor that detects the engine load are input to the electronic control unit 24,
The control rod 21 of the electronic speed governor 2 is controlled by the output signals of the electronic control unit 24 based on these signals. In addition, electronic speed governor 2 due to circuit disconnection / short circuit or radio interference
Is abnormal, the signal applied from the electronic control unit 24 to the electromagnetic switching valve 28 via the lead wire 27 is stopped,
Pressurized air is no longer supplied from the air pressure source 30 to the actuator 5 described later through the electromagnetic switching valve 28 and the pipe 29, and the working chamber of the actuator 5 is opened to the atmosphere.

As is well known, in the mechanical speed governor 3, the link mechanism operates in association with a shaft member that axially moves according to the depression amount of the accelerator pedal and the expansion amount of the centrifugal weight rotated by the engine. Finally, the control rod 31 is controlled. The control rod 31 projects into the case 4 and is supported by a bearing 32 so as to be movable in the axial direction. Each control rod 21, 3
1 is arranged in parallel with the fuel control rack rod 11.

The electronic speed governor 2 controls the fuel injection pump 1 as it is by connecting the control rod 21 to the fuel control rack rod 11, and the mechanical speed governor 3 shifts the control rod 31 to the fuel control rack rod 11. If connected, the fuel injection pump 1 can be controlled as it is.

According to the present invention, the operation of the control rod 21 or the control rod 31 is selectively transmitted to the fuel control rack rod 11 via the switching link mechanism 6. The right end of the link 44 is connected to the control rod 21 by the pin 43, and the left end of the link 44 is connected to the upper end of the guide link 41 by the pin 43. The lower end of the guide link 41 is connected to the control rod 31 by a pin 43a. The guide link 41 has a slit or a long hole 41a extending in the longitudinal direction.
Is provided, and the right end of the switching link 47 is slidably engaged with the elongated hole 41a by the pin 46. The left end of the switching link 47 is connected to the fuel control rack rod 11 by the pin 12. In order to change the inclination of the switching link 47 without hindering the lateral movement of the switching link 47, a pin 48 connected to an intermediate portion of the switching link 47 has a guide rod 49 parallel to the fuel control rack rod 11.
Is engaged with the long hole 49a. In order to move the guide rod 49 up and down, the guide rod 49 is integrally connected with a rod 54 projecting upward from the actuator 5. As is well known, the actuator 5 has a piston inserted into the inside of a cylinder so that the lower working chamber of the piston can communicate with the air pressure source 30 or the atmosphere, and the spring housed in the upper chamber projects the piston to the outside. The rod 54 is pushed down.

Next, the operation of the electronic / mechanical composite speed governor according to the present invention will be described. As shown in FIG. 1, when the fuel injection pump 1 is controlled by the mechanical speed governor 3,
The electromagnetic switching valve 28 is demagnetized, and the rod 54 of the actuator 5 is pushed down by the force of the spring. Therefore, the switching link 47 is tilted to the lower right, the pin 46 moves to the lower end of the elongated hole 41a, and approaches the pin 43a. In this state, even if the control rod 21 of the electronic speed governor 2 moves to the left and right, the guide link 41 only swings around the pin 43a with a slight bending of the link 44, and the switching link 47 moves. Does not affect exercise. When the control rod 31 of the mechanical speed governor 3 is moved left and right, the switching link 47 is moved in parallel along the elongated hole 49a of the guide rod 49 with the same inclination, and the fuel control rack rod 11 is moved left and right. At this time, the guide link 41 slightly rotates around the pin 43a.

As shown in FIG. 2, the fuel injection pump 1 is usually controlled by an electronic speed governor 2. At this time, the electromagnetic switching valve 28 is excited by the output signal of the electronic control unit 24, and pressurized air from the air pressure source 30 is transferred to the electromagnetic switching valve 28 and the pipe 29.
Is supplied to the working chamber of the actuator 5 via the
4 is pushed up. Therefore, the switching link 47 is connected to the fuel control rack rod 11 and the control rod 21 of the electronic speed governor 2.
Line up almost in line with. The lateral movement of the control rod 21 is transmitted to the fuel control rack rod 11 via the link 44, the guide link 41, and the switching link 47. At this time, even if the control rod 31 of the mechanical governor 3 moves to the left or right, the guide link 41 only swings about the pin 43 and does not affect the movement of the fuel control rack rod 11.

As is clear from the above description, the pin 4
By disposing 3,3a at a position overlapping the long hole 41a of the guide link 41, the pin 46 and the pin 43 match when the electronic speed governor 2 is used, and the pin 46 and the pin 43 when the mechanical speed governor is used. 43a coincides with each other, and more precise control can be obtained. If the guide link 41 is loosely connected to the control rods 21 and 31 so as not to hinder the axial movement, the link 44 is unnecessary.

As described above, according to the present invention, the fuel injection pump 1 is normally controlled with high accuracy by the electronic speed governor 2, and when an abnormality occurs in the electronic speed governor 2, for example, an electronic speed governor 2 is used. When the output signal from the controller 24 is stopped, the electromagnetic switching valve 28 is automatically demagnetized, and the rod 5 of the actuator 5 is demagnetized.
4 is pushed down by the force of the spring and switched to the mechanical speed governor 3 to be controlled. FIG. 3 shows the speed governing characteristics of the electronic speed governor 2 under high load, medium load and low load by lines A, B and C, and the speed governing characteristics of the mechanical speed governor 3 by lines D, E and F. Represent

The embodiment shown in FIGS. 4 to 6 is an electronic speed governor 2.
The control operation of No. 2 is limited within a certain range to prevent over-rotation of the engine due to runaway when the electronic speed governor 2 fails. For this reason, a V-shaped limiting member 51 (having a pattern for facilitating understanding) composed of arms 51a and 51b is integrally coupled to the control rod 31 of the mechanical speed governor 3, and the arm 5
The pin 46 is projected between 1a and 51b. Other configurations are similar to those of the embodiment shown in FIG. In this example,
When the mechanical speed governor 3 shown in FIG. 4 is operating, the pin 46 engages with the lower end of the restricting member 51, and the control rod 31, the switching link 47, and the fuel control rack rod 11 move integrally to the left and right. .. Even if the control rod 21 of the electronic speed governor 2 moves left and right, the guide link 41 only tilts around the pin 43a and does not affect the operation of the fuel control rack rod 11.

During operation of the electronic speed governor 2 shown in FIG. 6, the switching link 47 is pushed up by the rod 54 of the actuator 5 via the guide rod 49, and the control rod 21, the link 44, the switching link 47, and the fuel control. The rack rods 11 move to the left and right in a substantially straight line. At this time, since the pin 46 projects between the arms 51a and 51b, the control rod 2
The operation amount of 1 is restricted to the range of S1 + S2. Even if the control rod 31 of the mechanical governor 3 moves to the left and right, the link 41 only swings around the pin 43a, and does not affect the operation of the fuel control rack rod 11. The speed governing characteristics (broken line E) by the electronic speed governor 2 of the speed governing device shown in FIGS. 4 to 6 are regulated between the chain line E1 and the chain line E2 shown in FIG.

As shown in FIG. 8, if the elongated hole 41a of the guide link 41 in the above-described embodiment has an arcuate shape centered on the pin 12, the electronic speed governor 2 and the mechanical speed governor 3 will be described.
The switching operation between and can be obtained more smoothly.

As shown in FIG. 9, in order to perform the switching operation between the electronic speed governor 2 and the mechanical speed governor 3, the guide rod 49 of the actuator 5 vertically moves the pin 46 to move the switching link 47. The inclination may be changed.

As shown in FIG. 10, the electronic speed governor 2 and the mechanical speed governor 3 may be arranged on the left and right, depending on the conditions of attachment to the engine, and the control rods 21 and 31 control the fuel. If it is parallel to the rack rod 11, there is no problem.

In the modified embodiment shown in FIG. 11, in order to shorten the vertical dimension of the switching link mechanism 6, the actuator 5 is used.
The rod of the actuator 5 is connected to one end of a bell crank 56 supported by the support shaft 55 on the case 4 by a pin 58, and the rod of the actuator 5 is connected in parallel with the fuel control rack rod 11.
A pin 57 is connected to the other end of the bell crank 56, and a rod 54 movably supported by a bearing 60 is vertically connected to the case 4.

In the embodiment shown in FIG. 12, the switching link 47
As the actuator for changing the inclination of the switch, a three-position operation type actuator 5A can hold the switching link 47 even at an intermediate inclination. If the full speed governor 2a and the high / low speed governor 3a are connected to the switching link mechanism 6, as shown in FIGS. 13, 14 and 15, respectively, the full speed type governing characteristics and the full speed type and the high / low speed type governor are obtained. A speed control characteristic intermediate between those and a high / low speed speed control characteristic can be obtained.

[0023]

According to the present invention, as described above, the first control rod driven by the electronic speed governor and the second control rod driven by the mechanical speed governor are used for fuel control of the fuel injection pump. The first control rod and the second control rod are arranged in parallel with each other by a guide link, and the other end of the switching link, one end of which is connected to the fuel control rod, is used as a long hole of the guide link. Equipped with an actuator that slidably engages and engages a pin connected to the switching link with a long hole of a guide rod parallel to the fuel control rack rod and translates the guide rod in a direction perpendicular to the fuel control rack rod. Therefore, the amount of fuel in the engine can usually be controlled by an electronic speed governor with high control accuracy, and if the electronic speed governor is abnormal or malfunctions, it will instantly switch to a mechanical speed governor. There is no danger of the engine stopping or overspeeding Safety is improved.

According to the present invention, the electronic speed governor and the mechanical speed governor, each of which functions independently, are connected to the fuel control rack rod of the fuel injection pump through the switching link mechanism. The cost burden can be reduced by using the governor and mechanical governor as they are.

If the switching link mechanism is provided with a restricting member for restricting the operation of the electronic speed governor, abnormal operation of the electronic speed governor can be prevented, and abnormal operation can be detected to prompt repair.

[Brief description of drawings]

FIG. 1 is a side view showing a schematic configuration of an electronic / mechanical composite speed governor according to the present invention.

FIG. 2 is a side view showing an operating state of the electronic speed governor in the tuning speed device.

FIG. 3 is a diagram showing a speed control characteristic of a tuning speed device.

FIG. 4 is a side view of an electronic / mechanical speed governor according to a second embodiment of the present invention.

FIG. 5 is a bottom view of the tuning speed device.

FIG. 6 is a side view showing an operating state of the electronic speed governor of the tuning speed device.

FIG. 7 is a diagram showing a speed control characteristic of a tuning speed device.

FIG. 8 is a side view showing a modified embodiment of the switching link mechanism in the speed governor of the present invention.

FIG. 9 is a side view showing a modified embodiment of the switching link mechanism in the speed governor of the present invention.

FIG. 10 is a side view showing a modified embodiment of the arrangement of the speed governors in the speed governor of the present invention.

FIG. 11 is a side view showing a modified embodiment of the arrangement of actuators in the speed governor of the present invention.

FIG. 12 is a side view of a compound speed governor according to a third embodiment of the present invention.

FIG. 13 is a diagram showing a speed control characteristic of the tuning speed device.

FIG. 14 is a diagram showing a speed control characteristic of a tuning speed device.

FIG. 15 is a diagram showing a speed control characteristic of a tuning speed control device.

[Explanation of symbols]

1: Fuel injection pump 2: Electronic speed governor 3: Mechanical speed governor 5: Actuator 6: Switching link mechanism 1
1: Fuel control rack rod 21: Control rod 24: Electronic control device 31: Control rod 41: Guide link 41
a: long hole 47: switching link 48: pin 49: guide rod 49a: long hole

Continuation of the front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display area F02D 41/40 A 9039-3G

Claims (1)

[Claims] 1. A first control rod driven by an electronic speed governor and a second control rod driven by a mechanical speed governor are arranged parallel to a fuel control rack rod of a fuel injection pump. Then, the first control rod and the second control rod are connected by a guide link, and the other end of the switching link whose one end is connected to the fuel control rack rod is slidably engaged with the elongated hole of the guide link. An electronic device equipped with an actuator that engages a pin connected to the switching link with a long hole of a guide rod parallel to the fuel control rack rod and translates the guide rod in a direction perpendicular to the fuel control rack rod. Mechanical compound speed governor.