JPS634978Y2 - - Google Patents

Description

[Detailed description of the invention] [Technical field to which the invention pertains] The present invention relates to an improvement of a device for measuring the amount of fuel supplied to an internal combustion engine. In particular, it relates to a device for measuring fuel flow in order to test or tune an internal combustion engine.

[Description of prior art]

To outline this type of conventional fuel flow rate measuring device in FIG. 1, a fuel pipe 2 inserted into a fuel tank 1 in which fuel is stored is connected to a fuel pump 3, a valve 4, a cooler 5, a three-way valve 6, and a cooler. 5 to an internal combustion engine (not shown). A glass biuret 7 is erected on the three-sided pot 6. Phototube sensors 8 are provided around the barrel 7 at predetermined volumes. The detection output of this phototube sensor 8 is connected to a control circuit 9, and the output of this control circuit 9 is connected to a display circuit 10. The cooler 5 is a device that keeps the temperature of the fuel constant, 11 is a pressure gauge, and 12 is a return pipe from the engine.

In a device having such a configuration, the fuel pressure at the fuel supply end of the engine is different when the fuel flow rate is measured using the filter 7 and when the fuel flow rate is not measured with the filter 7 closed. do,
There were drawbacks that affected the institution's test results.

Particularly in diesel engines, the excess fuel that cannot be injected inside the fuel injection pump is removed by the fuel injection pump.
Immediately after that, it is returned through the return pipe 12. For this reason, the engine of the return pipe 12 and the filter 7
If the pressure difference between the return pipe 12 and the return pipe 12 is large, bubbles due to fuel vapor are likely to be generated in the return pipe 12, resulting in an apparent expansion of the fuel, which has the disadvantage of making it difficult to accurately measure the flow rate.

[Purpose of invention]

The present invention solves the above-mentioned drawbacks, and the present invention is a fuel flow measuring device for an internal combustion engine with which the pressure at the fuel supply end of the internal combustion engine when measuring the fuel flow rate is the same as the pressure when not measuring, and the measurement error is small. The purpose is to provide

[Characteristics of the invention]

The present invention includes a guide pipe branched into a fuel pipe connecting a fuel tank and an internal combustion engine, and a branched vertically provided fuel pipe on the downstream side of the guide pipe, with one end of the guide pipe at the top. a cylinder to which is connected, a valve interposed in a fuel pipe between the cylinder and the guide pipe, a pilot plate that slides within the cylinder so that there is no flow of fuel above and below the cylinder, and the pilot plate. a balancer capable of maintaining the position of the plate in the cylinder at a predetermined position without fuel flowing into the cylinder; a displacement sensor installed around the cylinder to detect the displacement of the pilot plate as an electrical signal; The present invention is characterized by comprising a control means including a calculation circuit that calculates the flow rate of fuel passing through the cylinder based on the detection output of the sensor, and a display means that displays the calculation result of the calculation circuit.

[Explanation based on examples]

An explanation will be given below based on the drawings of the embodiment.

FIG. 2 is a block diagram of an apparatus according to an embodiment of the present invention.
In FIG. 2, the fuel pipe 2 is provided with a guide pipe 19 branching off. This guide pipe 1
A solenoid valve 20 is provided at the bottom of the valve 9 . Further, a glass cylinder 21 is branched and installed upright in the fuel pipe 2 on the downstream side of the guide pipe 19. A solenoid valve 23 is provided in the fuel pipe 2 between the cylinder 21 and the guide pipe 19. Furthermore, one end of a guide pipe 19 is connected to the upper part of the cylinder 21 . A plurality of thin iron disc pilot plates 24 are loosely inserted into the cylinder 21. The plurality of pilot plates 24 are fixed by fixing rods 25 at predetermined intervals.

In this example, the plurality of pilot plates 24 are
As shown in the figure, using the lowest pilot plate 24a as a reference plate, set the pilot plate 24b so that the volume of the cylinder 21 surrounded by this pilot plate 24a and the immediately above pilot plate 24b becomes "25 c.c." The position of can be determined. Also, pilot board 2
The position of 4c is determined so that the volume of the cylinder 21 surrounded by the pilot plate 24a is "50 c.c.". Similarly, the position of the pilot plate 24d is set to "100c.c.", the position of the pilot board 24e is set to "200c.c.", and the position of the pilot board 24f is set to "400c.c.".
cc" respectively.

Returning to FIG. 2, the plurality of pilot plates 2
A balance rod 26 is inserted through the center of each of the balance rods 4, and a wire 27 is connected to one end of the balance rod 26. This wire 27 is configured to be wound onto a take-up pulley 30 of a stepping motor 29 via a pulley 28. 31 is an air bleed valve, and 32 is an oil seal ring.

Further, a phototube sensor 33 is attached to the outside of the cylinder 21 at approximately the middle thereof. The output of this phototube sensor 33 is connected to a control circuit 34.
This control circuit 34 includes a microcomputer 35 that calculates the flow rate of fuel passing through the cylinder 21 based on the output of the sensor 33. The output of this control circuit 34 is connected to the electromagnetic valves 20 and 23 and the stepping motor 29. Furthermore, the output of the control circuit 34 is connected to a display circuit 36 that displays the calculated fuel flow rate.

With such a configuration, the operation of the apparatus of this embodiment will be explained. First, the solenoid valves 20 and 23 are opened, the stepping motor 29 is driven by the control output of the control circuit 34, the wire 27 is wound up, the balance rod 26 is pulled up, and the lowest pilot plate 2 is
4a is positioned above the phototube sensor 33.
Further, the air vent valve 31 is opened to bleed the air. Next, the electromagnetic valve 20 is closed, and the stepping motor 29 is powered on so that the pilot plate 24 stops at a predetermined position within the cylinder 21 without sinking due to its own weight, thereby completing the measurement preparation work.

Next, the solenoid valve 20 is opened and the solenoid valve 23 is closed to drive the internal combustion engine that requires measurement, and the fuel is supplied to the second
Flow in the direction shown by the solid arrow in the figure. As fuel is consumed by the engine, the pilot plate 2
4 is displaced downward. When the pilot plate 24a serving as a reference plate is detected by the phototube sensor 33, the microcomputer 35 starts measurement, and when the next pilot plate 24b is detected by the sensor 33, the display circuit 36 displays the measurement result as “25c. c.” is displayed. Similarly, when the pilot plate 24d is detected by the sensor 33, "100c.c." is displayed on the display circuit 36.

When the measurement is completed, the control circuit 34 closes the solenoid valve 2.
0 is closed, the solenoid valve 23 is opened, and fuel is supplied to the engine without passing through the cylinder 21, as shown by the broken line arrow in FIG.

[Explanation of application examples]

In the above example, the phototube sensor 33 is used to detect the displacement of the pilot plate 24, but
If the pilot plate 24 is made of a magnetic material and the cylinder 21 is made of a non-magnetic material as in the above example, the present invention can be implemented in the same way even if a magnetic sensor is used in place of the phototube sensor 33. .

Further, the pilot plate 24 is not limited to a circular plate but may have other shapes, and when a phototube sensor 33 is used, it is not limited to iron but may be made of other materials.

Moreover, when a magnetic sensor is used for the cylinder 21, other materials may be used instead of glass.

In addition, the control circuit 3 controls the opening and closing of the solenoid valves 20 and 23.
4, but a manually opened/closed valve may be used instead.

In addition, the stepping motor 29 causes the cylinder 2 to
Although an example has been shown in which the pilot plate 24 is maintained in a fixed position when fuel does not flow through the fuel pump 1, the present invention is not limited to the above example as long as the balancer can maintain the pilot plate 24 in this fixed position.

Further, the positions of the plurality of pilot plates 24 can be set as appropriate depending on the conditions to be measured.

In addition, a timer circuit is built into the control circuit 34, and an accurate fuel consumption rate (cc/sec) is obtained from the number of seconds counted by this timer circuit, and this fuel consumption rate (cc/sec) is displayed together with the fuel flow rate. It can also be displayed on circuit 36.

Furthermore, the liquid to be measured is not limited to fuel for internal combustion engines, but can also be applied to other liquids.

[Effect of idea]

As described above, according to the present invention, a guide pipe is provided branching off to the fuel pipe, a pilot plate is loosely inserted into the cylinder, and the cylinder is filled with fuel through the guide pipe to control the displacement of the pilot plate. By configuring the fuel flow rate to be measured by detecting it with a displacement sensor, (a) the pressure sent to the internal combustion engine remains constant and does not change when not being measured; (b) Measurement accuracy does not deteriorate even if the fuel contains impurities; (c) The pilot plate moves up and down, making it difficult for dirt to adhere to the inner wall of the cylinder. (d) An excellent fuel flow measuring device for an internal combustion engine can be obtained, which requires fewer displacement sensors, has a simple mechanism, and requires less man-hours for maintenance.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of a conventional device. FIG. 2 is a configuration diagram of an apparatus according to an embodiment of the present invention. Figure 3 is an enlarged diagram of its main parts. 2...Fuel pipe, 19...Guide pipe, 2
0, 23...Solenoid valve, 21...Cylinder, 24...
... Pilot plate, 25 ... Fixed rod, 26 ... Balance rod, 27 ... Wire, 28, 30 ... Pulley, 29 ... Stepping motor, 31 ... Air bleeding valve, 32 ... Oil seal ring ,
33...Phototube sensor, 34...Control circuit, 3
5...Microcomputer, 36...Display circuit.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) In a device that is installed in a fuel pipe that connects a fuel tank and an internal combustion engine and measures the fuel flow rate of the engine, a guide pipe that is branched from the fuel pipe. and a cylinder branching off from the fuel pipe on the downstream side of the guide pipe and having one end of the guide pipe connected to its upper part, and a cylinder interposed in the fuel pipe between the cylinder and the guide pipe. a valve; a pilot plate that slides in the cylinder so that no fuel flows above and below the cylinder; and the pilot plate is capable of maintaining a predetermined position in the cylinder without fuel flowing into the cylinder. A control means including a balancer, a displacement sensor disposed around the cylinder and detecting the displacement of the pilot plate as an electric signal, and an arithmetic circuit that calculates the flow rate of fuel passing through the cylinder based on the detection output of the displacement sensor; A fuel flow rate measuring device for an internal combustion engine, comprising: display means for displaying the calculation results of the calculation circuit. (2) The fuel flow rate measuring device for an internal combustion engine according to claim 1, wherein the cylinder is made of a translucent material and the displacement sensor is a phototube sensor. (3) The fuel flow rate measuring device for an internal combustion engine according to claim (1), wherein the cylinder is made of a non-magnetic material, the pilot plate is made of a magnetic material, and the displacement sensor is a magnetic sensor.