JPH1030530A - Injection testing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily control a continuous or intermittent injection and improve measuring accuracy, in a testing device for which a jerk fuel injector is used. SOLUTION: A switching valve 5 is provided on the midway in a fuel piping 4 connecting a jerk fuel injection pump 2 and an injection valve 3, fuel from an injection pump 2 is fed to the injection valve 3 when an injection is performed and fuel from the injection pump 2 is leaked when the injection is not performed. An injection interval and a photographing time can be freely set, the switching valve 5 is operated so as to obtain a set injection interval based on the revolution signal from the injection pump 2 and a photographing device is operated so that a photographing may be performed when a photographing time is set. The revolution signals from the injection pump 2 are trigger signals and revolution angle signals of a pulse per revolution. The switching valve 5 and the photographing device are operated based on the trigger signals and based on the trigger signals and the revolution angle signals, respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to various characteristics of spray by disposing a switching valve in the middle of a pipe connecting an injection pump and an injection valve and controlling the switching valve to form continuous or intermittent injection. The present invention relates to an injection test device used for observing a jet.

[0002]

2. Description of the Related Art Conventionally, as a single injection device for research,
Accumulation type injection devices are widely used. For example, an electromagnetic single injection system using three DC solenoids (Transactions of the Japan Society of Mechanical Engineers, vol. 54, No. 501, volume B (Showa 6)
3), p1194: hereinafter referred to as the first prior art), and a single-shot high-pressure injection system using a large-sized rapid compression device (Transactions of the Japan Society of Mechanical Engineers, Vol. 53, No. 487, Edition B, Sho 62)
117: hereinafter referred to as a second prior art).

The first prior art injection system employs a method in which a needle of an injection valve is urged in a valve closing direction by a spring force, and the needle is driven in a valve opening direction against a spring force by energizing a DC solenoid. The valve opening pressure of the nozzle due to the spring force is set to be higher than the accumulated pressure. The spring force is
It is sufficient to set the valve opening pressure slightly higher than the accumulated pressure, but in order to realize high-speed operation of several milliseconds, the spring force is increased, and three DC solenoids are provided in series to enhance the exciting force. Is being planned. Further, the injection device of the second prior art is provided with a mechanism for controlling the opening and closing operation of the needle by hydraulic pressure, and a mechanism for supplying fuel to the compression chamber and compressing the same by the plunger. The timing is electrically controlled to obtain a high voltage.

Further, as a test device, a control rack position of a jerk type fuel injection device is controlled (Japanese Society of Mechanical Engineers Chugoku-Shikoku Branch Okayama Regional Lectures, Vol. 1).
988, pp40-41: Transactions of the Japan Society of Mechanical Engineers, 57, 5
No. 37, Volume B (1991), p1886: hereinafter referred to as a third conventional technique), a high-pressure injection pipe connecting between a pump and an injection valve is branched in the middle thereof, and the branched portion is lower than the injection valve. A device in which a dummy nozzle having a valve opening pressure is provided and the branch direction of fuel pumped from a pump is switched manually or by a solenoid valve or the like (Transactions of the Society of Automotive Engineers of Japan,
No. 30, 1985, pp10-15: hereinafter referred to as a fourth prior art).

[0005]

However, in the first and second prior arts, data is collected only under conditions that are almost distant from the jerk type fuel injection pump, which is the main injection device that has been put into practical use. It cannot be used for spray analysis of jerk-type fuel injection pumps. Further, in the third conventional technique using a jerk type fuel injection pump, since the control rack position is controlled, it is difficult to obtain high responsiveness and the injection specifications are limited. In the technology, since the pipe from the injection pump to the injection valve is branched for a dummy nozzle, the volume (dead volume) between the injection pump and the injection valve is greatly increased compared to the actual machine,
Characteristics such as injection pressure, needle valve lift, injection rate, and the like did not correlate with the characteristics of the actual machine itself, and a spray suitable for the actual machine could not be obtained.

Therefore, in the present invention, in a test device using a practical jerk type fuel injection device, switching of various injection specifications can be controlled easily and with good responsiveness, and various injections (characteristics similar to those of an actual machine) can be performed. It is an object to provide an injection test apparatus capable of reproducing continuous injection, intermittent injection, and single injection). It is another object of the present invention to easily install and replace the injection pump and improve the operability and control accuracy of the test apparatus.

[0007]

In order to solve the above-mentioned problems, the present applicant has set a switching valve in the middle of a pipe and usually opens the switching valve to leak fuel and perform injection only when it is desired to perform injection. We have begun to develop an injection test device with good responsiveness that closes the switching valve and injects. In order to accurately form and measure spray using such a switching valve, it is necessary to use an injection pump. The inventors have found that a signal synchronized with rotation can be used, and as a result of intensive research on the development of a practical test device with good operability, the present invention has been completed.

That is, an injection test apparatus according to the present invention is provided with a jerk type injection pump, an injection valve connected via a pipe to a delivery section of the injection pump for pressurizing a pressurized fluid, and provided in the middle of the pipe. An inlet passage for flowing a fluid pumped from an injection pump, an outlet passage leading to the injection valve, and a leak passage for leaking the fluid, wherein the fluid flowing into the inlet passage is provided at the outlet. A switching valve for switching between the passage portion and the leak passage portion, a rotation pulse output means for outputting a fixed number of pulses per unit rotation with the rotation of the injection pump, and an injection for setting an injection specification of the fluid A signal for opening and closing the switching valve in accordance with the injection specification set by the injection specification setting means based on a pulse output from the rotation pulse output means; The communication between the inlet passage portion and the leak passage portion is interrupted during the injection based on the above, and the fluid flowing in from the inlet passage portion is sent to the outlet passage portion. Switching valve control means for communicating the fluid flowing from the inlet passage with the leak passage through the leak passage to allow the fluid to flow through the leak passage.

Therefore, a signal synchronized with the rotation of the injection pump is output by the rotation pulse output means, and based on this signal, the switching valve is controlled as set by the injection specification setting means. Then, the communication between the inlet passage and the leak passage is disconnected, and the fluid flowing into the inlet passage of the switching valve is sent to the injection valve via the outlet passage. As a result, the fluid pumped from the injection pump is sent only to the piping leading to the injection valve, and is injected from the injection valve when the fluid pressure becomes higher than the valve opening pressure of the injection valve.

At times other than the injection based on the set injection specifications, the inlet passage and the leak passage communicate with each other, and the fluid flowing into the inlet passage flows into the leak passage, and the device passes through the leak passage. As a result, the pressure in the pipe from the outlet passage to the injection valve falls below the valve opening pressure of the injection valve, and injection is not performed.

In order to improve the control accuracy, the pulse output from the rotation pulse output means includes a trigger signal output once per unit rotation of the injection pump and a rotation angle signal output per unit rotation angle. (Claim 4), it is desirable to set the injection specifications so that the total number of injections and the injection interval can be set arbitrarily, so that continuous injection or intermittent injection can be realized. (Claim 5). In particular, in order to analyze a single injection, it is necessary to prevent the spray from interfering with the previously sprayed spray. However, such non-interfering injection requires a plurality of rotations as the rotation speed of the injection pump increases. It cannot be obtained unless it is one intermittent injection.

Further, the jerk type injection pump usually has a plurality of delivery sections. However, even if an injection valve is provided in each delivery section via a pipe, the influence of an increase in the load of the injection pump can be obtained. In order to eliminate the problem, the injection valve may be connected to only one delivery section via a pipe (claim 2).

By the way, even when the inlet passage communicates with the leak passage and the fluid is leaking, it is desirable to maintain a predetermined residual pressure in the pipe from the outlet passage to the injection valve. For this reason, it is desirable to provide a residual pressure holding mechanism for maintaining a constant residual pressure lower than the valve opening pressure of the injection valve in the leak passage portion of the switching valve. Thereby, even if the fluid is leaking, the inside of the pipe from the outlet passage to the injection valve is maintained at a predetermined residual pressure, and when the communication between the inlet passage and the leak passage is cut off, the pressure in the pipe is reduced. Is quickly raised.

Further, in order to photograph the injected spray,
A photographing device for photographing the spray, photographing specification setting means for setting the photographing specification of the spray, and operating the photographing device according to the photographing specification set by the photographing specification setting means based on the pulse output from the rotating pulse output means. It is desirable to have a photographing device control means for forming a signal.
At this time, as the setting of the shooting specification, the setting of the shooting specification is set to the shooting timing, and the number of injections from the start of injection to the shooting and the rotation angle from the start of injection to the shooting at the set injection may be set. Item 7).

By adding such a configuration, the photographing timing can be arbitrarily set separately from the injection timing. However, since the photographing device operates based on the pulse output from the rotating pulse output means, the setting can be performed. It is possible to shoot with high precision using the specified shooting specifications.

[0016]

Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 1, the injection test apparatus mounts and fixes a jerk-type fuel injection pump 2 for compressing fuel supplied from a fuel tank 1 on a pump tester (not shown). 2a is connected to the injection valve 3 by the fuel pipe 4, and the other oil feeding section 2a
Is designed to return the delivered fuel to the fuel tank 1. A high-speed switching valve (ZELS) 5 is provided in the middle of the fuel pipe 4, and the current supplied to the switching valve 5 is supplied from the drive unit 6. The supply timing of the current from the drive unit 6 is determined by an input signal from the control unit 7,
These drive unit 6 and control unit 7
Is supplied with a constant voltage from the power supply 8.

The injection pump 2 is provided with a rotation sensor 10. The rotation sensor 10 has a trigger signal of one pulse per rotation and a rotation angle of 360 pulses per rotation as the camshaft rotates. And a signal to the control unit 7.

The injection nozzle 3 is arranged with the injection hole facing the measurement space 11, and the spray injected into the measurement space 11 receives a signal from the control unit 7, such as a strobe 12, a camera, a video 13, or the like. The image is taken by a photographing device.

FIG. 2 shows a switching valve 5 disposed in the middle of the fuel pipe 4. The switching valve 5 sends the fuel pressure-fed from the injection pump 2 to the injection valve 3 at the time of supplying the electric current, and at the time of non-supply of the electric current. The fuel is returned to the fuel tank 1. The inlet passage 16 through which the fuel pumped from the injection pump 2 flows and the injection valve 3
Block 1 having an outlet passage portion 17 leading to the first block 1
8, a second block 19 fixed to the first block 18 and containing the stator 22 of the solenoid valve, and a fuel block similarly fixed to the first block 18 but provided on the opposite side to the second block 19, And a third block 21 provided with a leak passage portion 20 for leaking water.

The first block 18 has, at its center, a sliding hole 23 through which a needle 36 of an electromagnetic valve, which will be described later, is inserted.
First and second mounting holes 24 and 25 drilled from the side surface of the block 18 and the respective mounting holes 24 and 25
The first and second oil supply passages 26 and 27 are formed so as to communicate with the slide hole 23 at the shortest distance. The first attachment hole 24 has substantially the same diameter as the passage diameter (about 2 mm) of the fuel pipe 4. A fuel inflow connector 29 having the same configuration as the fuel inflow connector 28 is screwed into the second mounting hole 25. The fuel inflow connector 28 and the first oil passage 26 constitute the inlet passage 16, and the fuel outflow connector 29 and the second oil passage 27 constitute the outlet passage 17.

In particular, in this configuration example, the inlet passage 16 and the outlet passage 17 are formed to have substantially the same diameter as the passage diameter (about 2 mm) of the fuel pipe 4 and symmetrically with respect to the slide hole 23 ( 180 degrees out of phase)
The first and second oil supply passages 26 and 27 are provided perpendicular to the sliding hole 23 and opposed to each other so that their respective center lines coincide with each other.

In the second block 19, a base 30 is fixed to the first block 18 by screws or the like, and a stator housing barrel 32 for housing the stator 22 is applied to the base 30 via a spacer 31. The storage barrel 32 is fastened to the base 30 by a holder nut 33.

An insertion hole 34 is formed in the base 30 of the second block 19 at a position aligned with the slide hole 23.
An armature storage chamber 35 is formed between the base 30 and the spacer 31, and one end of the needle 36 of the solenoid valve inserted through the sliding hole 23 and the insertion hole 34 is stored in the armature storage chamber 35. The armature 37 is fixed.

The needle 36 has a valve head 38 formed at the end opposite to the side to which the armature 37 is connected, and the valve head 38 is formed in a conical shape to form the first block 18 and the third block 21. , And protrudes into a spill space 39 formed by the above, and a peripheral edge of an end of the sliding hole 23 is a valve seat 40. Further, in the spill space, a stopper 49 for setting a moving amount of the needle 36, that is, a distance at which the valve head 38 separates from the toilet seat 40 is provided with the first and third blocks 18, 21.
Is provided on the member holding the.

The sliding hole 23 is formed to have substantially the same diameter as the diameter of the needle 36, and the needle 36 is formed so as to slide on the inner surface of the hole.
The insertion hole 34 formed in the base 30 has a large diameter so as not to contact the needle 36, and forms a spring storage space 41 around the needle 36.
In addition, the opening end of the insertion hole 34 of the armature storage chamber 35 is somewhat narrowed, so that the second block 1
9, a spring receiver 42 is formed. A spring 43 is provided between the spring receiving space 42 and the step formed in the needle 36.
The spring 43 applies an urging force for separating the valve head 38 from the valve seat 40 by the needle 36 at all times.
In addition to

The electromagnetic valve stator 22 includes an exciting coil 46.
Is wound into the stator housing barrel 32 through the mounting hole 44 of the spacer 31 so that the end face of the stator core 45 matches the end face of the spacer 31 so that a slight gap is formed between the stator core 45 and the armature 37. Are facing each other. Therefore, when the excitation coil 46 is energized from the drive unit 6, the armature 3
7 is attracted to the stator core 45 against the spring 43, the valve head 38 is seated on the valve seat 40, and when the power is cut off, the armature 37 moves away from the stator core 45 by the spring force of the spring 43, and the valve head 38 It is separated from the seat 40.

Further, in order to reduce the dead volume of the oil feed passage, an annular groove 48 having a somewhat smaller diameter is formed in the needle 36 at a portion before the valve head 38. When the valve head 38 is separated from the valve seat 40, the annular groove 48 is used for the first and second oil supply passages 2.
The fuel in the fuel pipe 4 overflows into the leak passage portion 20 by communicating the fuel passages 6 and 27 with the leak passage portion 20, and the valve head 38
Is seated on the valve seat 40, the first oil supply passage 26
Has a function of communicating only with the second oil supply path 27.

The leak passage section 20 has a spill space 39,
A passage 50 penetrating through the third block 21 and having one end connected to the spill space 39 and an open end closed by the closing member 47, a third mounting hole 51 formed in the side surface of the third block 21, It is constituted by a third oil feed passage 52 that connects the attachment hole 51 and the passage 50.

A check valve 5 is provided in the third mounting hole 51.
As shown in FIG. 3, the check valve 53 is provided with a seat member 56 in a through hole 55 of the holder 54.
And a relief valve 57 is housed in a space surrounded by the holder 54 and the seat member 56, and the relief valve 57 is slidably inserted into the through hole 58 of the seat member 56,
The relief valve 57 is pressed against a valve seat 59 formed on the seat member 56 by a spring 60, and the seat member 5
A ball valve 62 that opens and closes a through hole 61 of the relief valve 57 is urged by a spring 63 at an end of the relief valve 57 inserted in 6 in a direction opposite to the urging direction of the relief valve 57.

As shown in FIG. 1, the control unit 7 is inputted to a trigger input terminal 65 for inputting a trigger signal from the rotation sensor 10, an angle signal input terminal 66 for inputting a rotation angle signal, and an angle signal input terminal 66. Signal 1
A synchronization signal of 360 pulses (360 / rev) per rotation or 3600 pulses (3600 / rev) multiplied by 10
), A resolution switch 67 for selecting whether to use a synchronization signal, a power switch 68 for driving / stopping the injection test apparatus, a start switch 69 for manually instructing the start of injection and measurement, and inputting an external pulse for starting injection and measurement. Start signal input terminal 70, the number of injections setting unit 71 for setting the total number of injections, continuous injection (injection once per rotation), 1/2 intermittent injection (injection once every two rotations) ), 1/3 intermittent injection (injection once every 3 rotations), 1/4
Injection interval changeover switch 72 for switching to intermittent injection (injection once every four rotations), injection delay setting unit 7 for setting the number of injections (injection delay) from the start of injection to shooting.
3. Set the rotation angle (delay angle from the reference signal) for shooting the injection set by the injection delay setting unit 73 D
An output terminal 7 that outputs a drive signal for operating the strobe 12, the camera 13, or the like at the shooting timing set by the elay angle setting unit 74, the ejection delay setting unit 73, or the delay angle setting unit 74.
5, and an output terminal 76 for a command signal for commanding the timing at which the drive current flows to the switching valve 5.

The injection delay setting unit 73 and the delay angle setting unit 74 are provided in three sets so that three different photographing times can be set (73a, 74a: 73b, 74b: 73c, 74).
c) Also, three output terminals 75 are provided corresponding to each set (75a, 75b, 75c), and the injection Del of each set is performed.
When the shooting time set by the ay setting unit 73 and the delay angle setting unit 74 is reached, a shooting signal is output from the corresponding output terminal 75 to the strobe 12, the camera 13, or the like, and data sampling is performed.

The internal operation of the control unit 7 is schematically shown in FIG. 4, and the number of injections is counted and the switching valve 5 is selected by the rotation signal obtained from the injection pump 2 and selection by the resolution switch 67. A synchronizing signal used for the timing of outputting the driving signal and a synchronizing signal used for the photographing timing are generated (block 81), and a start pulse is generated based on a signal input from the start switch 69 or an external pulse. Is generated (block 82). Specifically, the synchronizing signal is generated by generating a reference signal (reference pulse) once per rotation by a trigger signal, and at a resolution of 360 / rev at a resolution selected by the resolution switch 67 based on the rotation angle signal. Alternatively, a pulse of 3600 / rev is generated.

The input signal from the rotation sensor is TTL
Signal or an analog signal from an electromagnetic pickup. The rotation signal is TTL for the synchronization signal.
A signal is formed by capturing the falling edge of the signal, and an analog signal is formed by capturing the zero cross of the signal. Also, the reference signal is
The trigger signal may be formed in phase with the trigger signal, or a predetermined offset may be provided to the trigger signal.

When the start pulse is generated, a drive signal to be output to the drive unit in synchronization with the synchronization signal is generated in accordance with the injection specification set by the injection number setting section 71 and the injection interval switch 72 (block 83). The drive signal instructs the energization timing and energization time of the switching valve 5, and may be generated in accordance with the reference signal at each set injection interval, or may be generated before the reference signal. Is also good. Then, the generated drive signal is output to the drive unit 6, and
Upon receiving this signal, the drive unit 6 performs an energization control for energizing the switching valve 5 (block 8).
4).

The number of injections is counted based on the synchronization signal, and an imaging signal for operating a camera, a strobe, or the like is generated at the time of imaging set by the injection delay setting unit and the delay angle setting unit (block). 8
5). That is, the photographing signal is a signal for instructing the timing of operating the photographing device, and is generated at a delay angle from the reference signal of the set number of times of injection.

The control operation of the injection test apparatus over time using the control unit for performing the above-described processing will be described with reference to the flowchart of FIG. 5. When the injection test is performed, the power switch 68 of the control unit 7 is turned off.
N (step 100), and the resolution selection switch 67 is selected to be either 360 pulses / rev or 3600 pulses / rev (step 102).

Further, the shooting timing to be shot is set by the injection delay setting section 73 and the delay angle setting section 74 (steps 104 and 106), and the injection number setting section 71 is set.
Then, the total number of injections and the injection dividing ratio are set by the injection interval switch 72 (steps 108 and 110). still,
The injection pump 2 is driven at a predetermined rotation speed in advance.

A synchronizing signal is generated based on the rotation angle signal and the trigger signal input from the rotation sensor 10 (step 112), and waits for the start switch 69 to be turned on or the input of an external pulse. Manual start switch 6
9 or an external injection / measurement start instruction is input, a start pulse is generated, injection / measurement is started (step 114), and continuous or intermittent injection is started at a set injection interval. At the same time, a photographing signal is output at the set photographing time (steps 116 and 11).
8).

When the injection is performed the set number of times, the injection is automatically terminated (step 120).
If measurement is to be continued again, the settings in steps 104 to 110 are redone, and if measurement is to be ended, the power switch 68 is turned off (steps 122 and 124).

In the above configuration, a control signal 7 is used which forms a reference signal having no offset from the trigger signal from the rotation sensor 10 and generates the reference signal at the same timing as the output timing of the drive signal. For example, if the number of injections is 200,
The second shooting timing is set to the delay angle 21.5 of the second injection.
°, the second shooting timing is the delay angle of 9.8 ° of the eleventh injection, and the third shooting timing is the D of the 156th injection.
It is assumed that each setting unit is set as shown in FIG. 1 in order to set the elay angle to 36.3 °. The start of the injection is performed by the start switch 69.

If it is desired to perform shooting at the timing set as described above under continuous injection, the injection interval switch 72 is set to continuous (cont.) And the start switch 69 is pressed. Then, as shown in FIG. 6, a drive signal is generated in synchronization with the first reference signal after the start switch 69 is turned on.

Since the continuous injection is set, the drive signal is continuously output until the reference signal is generated 200 times, and the power supply from the drive unit 6 to the switching valve 5 is also continued during this time. Accordingly, the switching valve 5 is configured such that the needle 36 lifts and the valve head 38 seats on the valve seat 40,
The communication between the inlet passage section 16 and the leak passage section 20 is cut off, and the fuel pumped from the injection pump 2 is sent to the injection valve 3 to perform continuous injection once per rotation.

In the first shooting, the control unit 7 sets the second injection at 21.5 °, and when the second reference signal is generated after the start signal is generated, this signal is output. At a point of time when the delay is 21.5 ° as a reference, a photographing signal is output from the first output terminal 75a, and the spray at that rotation angle is photographed. Thereafter, similarly, the second and third
The second shooting is performed at the set timing, and after the three shootings are completed, the drive signal is turned off after 200 injections.
Becomes When the drive signal turns off, the spring 4
The valve head 38 is separated from the valve seat 40 by the spring force of 3,
Although the communication between the inlet passage 16 and the outlet passage 17 is not interrupted, the fuel sent from the injection pump 2 passes through the leak passage 20 because the inlet passage 16 also communicates with the leak passage 20. And returned to the fuel tank 1.

On the other hand, when it is desired to measure the spray in the half intermittent injection without changing the number of injections and the spray timing, the injection interval switch 72 is set to 1/2 and the start switch 69 is set. Press it, and this causes
As shown in FIG. 5, the drive signal is turned on every other rotation in synchronization with the reference signal, and the needle of the switching valve 5 is also moved to the valve seat 40 only while the drive signal is on.
And performs intermittent injection once every two rotations. In this case, the first photographing is performed at a point of time when the delay is delayed by 21.5 ° from the output of the third reference signal after the generation of the start signal. Similarly, the second and third shootings are performed at the set number of injections (the second shooting is performed at the time of the eleventh injection, that is, nine times after the 21st reference signal is output). .
At the time of the 8 ° delay, the third shooting is performed at the time of the 156th injection, that is, at the time of the delay of 36.3 ° from the output of the 311th reference signal), and 20
The injection is terminated after the 0th injection.

In such an injection, the fuel in the fuel pipe is returned to the fuel tank 1 from the leak passage portion 20 every other time, so that the residual pressure in the fuel pipe cannot be maintained as in the continuous injection, and the fuel is injected. Although there is a concern that the characteristics may change, the fuel leaking from the leak passage portion 20 during non-injection flows out through the check valve 53, and the check valve 53 is provided with a through hole formed in the relief valve 57. Since the orifice 64 is formed in the passage 61 to increase the passage resistance, the residual pressure in the leak passage decreases only slowly, and the residual pressure in the fuel pipe 2 is kept high as in the continuous injection. be able to. For this reason, even if the intermittent injection is selected, the pressure in the fuel pipe is quickly increased at the time of injection,
A spray having the same characteristics as continuous spray can be formed. Further, since the inlet passage 16 and the outlet passage 17 respectively face the needle 38 at the shortest distance, the passage length of the fuel path depends on whether or not the present apparatus is attached to the fuel pipe 4. It can be almost the same, and an increase in dead volume can be suppressed.

In consideration of the operation delay of the switching valve 5, the reference signal is set to a signal delayed by an offset time α with respect to the trigger signal input from the rotation sensor 10, and the generation of the drive signal is compared with the reference signal. It may be set so as to be advanced by the -start time β. Such a setting depends on the capacity (dead volume) of the switching valve 5, and it is necessary to consider the operation delay as the capacity increases.

FIGS. 8 and 9 show time charts when the offset time α and the pre-start time β are set, and the reference signal offset by α based on the trigger signal from the rotation sensor 10. Is generated, and the drive signal is generated at a point earlier by β than the first reference signal after the start signal is generated (after the falling point).

Therefore, the number of injections is counted using the offset reference signal. If continuous injection is set, the drive signal continues until the 200th reference signal is generated, as shown in FIG. At a time point delayed by 21.5 ° from the second reference signal at which the second injection is performed, the imaging signal is output to perform the first imaging of the spray. Thereafter, the second and third shots are performed at the set time, and the injection is terminated after the 200th injection.

If 1/2 intermittent injection is set, as shown in FIG. 9, a drive pulse output every other rotation is generated at a point earlier than the reference signal by a pre-start time β. In this case as well, a shooting signal is output at the time of the set shooting, and shooting of the spray is performed. For example, in the case of the first shooting, after the start signal is generated, a delay of 21.5 ° from the third reference signal is performed. At this point, a photographing signal is output.

As described above, by simply changing the setting of the control unit 7, it is possible to select either continuous injection or single injection and to set an arbitrary photographing timing. Can be easily measured. In addition, in order to increase the accuracy of the imaging timing, the resolution selection may be switched from 360 pulses / rev to 3600 pulses / rev, whereby highly accurate measurement can be realized.

[0052]

As described above, according to the present invention,
A switching valve that switches the fuel that has flowed into the inlet passage to the outlet passage and the leak passage is provided in the piping connecting the jerk-type injection pump and the injection valve, and is used for a pulse output from the rotation pulse output means. At the time of injection based on the injection specification set by the injection specification setting means in synchronization, the communication between the inlet passage and the leak passage is cut off and the fluid is injected from the injection valve, so that the injection timing is switched by the switching valve. Control can be performed only by timing, and responsiveness can be improved as compared with a conventional control rack. Further, in a jerk type injection pump which is most used at a practical level, various forms of injection can be easily formed by changing the setting of the injection specification, and in particular, if the setting of the injection interval is changed, Continuous injection, intermittent injection, and single injection can be easily obtained.

Further, since the switching valve is arranged in the middle of the pipe, it is only necessary to replace the switching valve for injection pumps of various scales.
Removal becomes easy, and a versatile test apparatus can be provided.

Further, one of the delivery sections of the jerk type injection pump is
If the injection valve is provided via a switching valve, it is not necessary to consider the effect of the difference in the load of the injection pump on spraying, and stable injection can be repeatedly obtained, and the single shot injection can be performed. An injection test device suitable for a basic experiment can be provided.

A residual pressure holding mechanism for maintaining a constant residual pressure lower than the valve opening pressure of the injection valve may be provided in the leak passage portion of the switching valve. Thus, the same injection as in the steady state can be obtained, and the responsiveness and control accuracy of the injection device can be improved.

The ejection timing and the photographing timing are based on the pulse output from the rotation pulse output means.
If this pulse is used as, for example, a trigger signal output once per unit rotation of the injection pump or a rotation angle signal output every unit rotation angle, control accuracy can be improved.

Further, if the photographing specification for controlling the photographing apparatus can be set by the photographing specification setting means, the photographing specification can be arbitrarily set separately from the ejection specification. By setting the number of times of spraying and the rotation angle until shooting at the set time of shooting, the shooting timing can be finely adjusted, and the accuracy of spray measurement can be improved.

[Brief description of the drawings]

FIG. 1 is a diagram showing an overall configuration of a fuel test apparatus according to the present invention.

FIG. 2 is a cross-sectional view showing a switching valve according to the present invention.

FIG. 3 is a sectional view showing a check valve used in the switching valve of FIG. 2;

FIG. 4 is a block diagram schematically showing a control process of a control unit shown in FIG. 1;

FIG. 5 is a flowchart illustrating a control operation over time of the injection test apparatus.

FIG. 6 is a time chart showing various signals during continuous injection in which a drive signal for controlling a switching valve is synchronized with a trigger signal from a rotation sensor.

FIG. 7 is a time chart showing various signals at the time of intermittent injection in which a drive signal for controlling a switching valve is synchronized with a trigger signal from a rotation sensor.

FIG. 8 is a diagram showing an example in which a reference signal offset from a trigger signal from a rotation sensor is formed, and a drive signal for controlling energization of a switching valve and a photographing signal for operating a photographing device are based on the reference signal. 5 is a time chart showing various signals at the time of continuous injection generated by the above-described embodiment.

FIG. 9 is a diagram showing an example in which a reference signal offset from a trigger signal from a rotation sensor is formed, and a drive signal for controlling the energization of the switching valve and a photographing signal for operating the photographing device are based on the reference signal. 6 is a time chart showing various signals at the time of intermittent injection generated by the above.

[Explanation of symbols]

 2 Fuel injection pump 3 Injection valve 4 Fuel pipe 5 Switching valve 6 Drive unit 7 Control unit 10 Rotation sensor 16 Inlet passage 17 Outlet passage 20 Leak passage 53 Check valve 71 Injection frequency setting unit 72 Injection interval changeover switch 73 Injection delay setting Section 74 Delay angle setting section

Claims (7)

[Claims] 1. A jerk-type injection pump, an injection valve connected via a pipe to a delivery section of the injection pump for pressure-feeding a pressurized fluid, and a fluid provided in the middle of the pipe and pumped from the injection pump. Having an inlet passage, an outlet passage leading to the injection valve, and a leak passage for leaking the fluid,
A switching valve for switching the flow of the fluid flowing into the inlet passage to the outlet passage and the leak passage, and a rotation pulse output for outputting a fixed number of pulses per unit rotation with the rotation of the injection pump. Means, an injection specification setting means for setting the injection specification of the fluid, and a signal for opening and closing the switching valve according to the injection specification set by the injection specification setting means based on the pulse output from the rotation pulse output means. Is formed, and at the time of injection based on the injection specification, communication between the inlet passage portion and the leak passage portion is cut off, and fluid flowing from the inlet passage portion is sent to the outlet passage portion. Switching valve control means for communicating the inlet passage portion with the leak passage portion at the time of injection and allowing the fluid flowing from the inlet passage to leak through the leak passage portion. And the injection test equipment. 2. The injection test apparatus according to claim 1, wherein the jerk type injection pump has a plurality of delivery portions, and the injection valve is connected to only one delivery portion via a pipe. 3. The switching valve according to claim 1, wherein the switching valve has a residual pressure holding mechanism for maintaining a constant residual pressure lower than a valve opening pressure of the injection valve in the leak passage portion. Injection test equipment. 4. The pulse output from the rotation pulse output means is a trigger signal output once per unit rotation of the injection pump and a rotation angle signal output per unit rotation angle. Injection test equipment. 5. The injection test apparatus according to claim 1, wherein the setting of the injection specification is a setting of a total number of injections and an injection interval. 6. A photographing device for photographing a spray injected from an injection valve, a photographing specification setting unit for setting a photographing specification of the spray, and the photographing specification setting unit based on a pulse output from the rotation pulse output unit. 2. An injection test apparatus according to claim 1, further comprising: a photographing device control means for generating a signal for operating said photographing device in accordance with the photographing specification set in (1). 7. The injection test according to claim 6, wherein the setting of the photographing specification is a setting of a photographing timing, and is a number of injections from the start of the injection to the photographing and a rotation angle from the start of the injection to the photographing at the set injection. apparatus.