BR112019026976A2 - device and process for adjusting back pressure for an injector - Google Patents

Abstract

The present invention relates to a device (10) for adjusting the back pressure for an injector (12) with a return tube (14) with a first end (14a), which is possible to connect directly or indirectly a return exhaust outlet (12a) from the injector (12) in such a way that a return volume (16) of the injector (12) flows from the first end (14a) of the return tube (14) to a second end (14b ) of the return pipe (14), and at least one valve (20) through which a return pressure of at least between the first end (14a) of the return pipe (14) and the valve (20) inside the pipe return valve (14) is adjustable, and the device (10) has an electrically adjustable throttle valve (20) like the valve (20). The invention also relates to a return block for injectors (12), a measuring device for measuring the injection volume and / or measuring the return volume for at least one injector (12) and a test stand for at least an injector (12). In addition, the invention relates to a process for adjusting back pressure in at least one injector (12).

Description

Invention Patent Descriptive Report for "PROVISIONS

RETURN PRESSURE ADJUSTMENT AND PROCESS FOR AN INJECTOR ".

[0001] The present invention relates to a device for adjusting the back pressure for an injector and a return block for injectors. In the same way, the invention relates to a measuring device for measuring injection volumes and / or measuring return volumes for at least one injector and a test stand for at least one injector. In addition, the invention relates to a process for adjusting back pressure in at least one injector. State of the art

[0002] Test stands for injectors (injection valves) and injection pumps are known from the state of the art, such as the test stand EPS 815 from Robert Bosch GmbH. Generally, during an evaluation of an injector, it is not measured only the injection volume, but also the return volume, by applying a back pressure. Description of the Invention

[0003] The invention creates a device for adjusting back pressure for an injector with the characteristics of claim 1, a return block for injectors with the characteristics of claim 7, a measuring device for measuring injection volumes and / or measurement of return volumes for at least one injector with the characteristics of claim 9, a test stand for at least one injector with the characteristics of claim 10 and a process for adjusting return pressure in at least one injector with the characteristics of claim 11. Advantages of the Invention

[0004] The use, according to the invention, of the electrically adjustable throttle valve to adjust / regulate the back pressure is relatively free of tolerance, so, when adjusting / regulating the back pressure, inaccuracies are avoided / reduced to a minimum. In particular with regard to conventional mechanical pressure check valves, which according to the current state of technology in general are used to adjust / regulate the back pressure (possibly in conjunction with a control valve), it is possible to adjust / adjust the back pressure more precisely / reliably by means of the electrically adjustable throttle valve. Since a difference in return pressure from a nominal return pressure in some types of injectors leads to a variation in the injection volume and / or the return volume, it can through the improved precision of the set return pressure / the quality of the injection volume and / or return volume measurements can also be increased (measurement variations are reduced respectively when measuring the injection volume and / or return volume).

[0005] In an advantageous embodiment of the device for adjusting back pressure the back pressure is adjustable via the electrically adjustable throttle valve at least between the first end of the return tube and the throttle valve electrically adjustable inside the return tube optionally to any return pressure value in a range of values with at least two different return pressure values. Generally, the return pressure can be varied by means of the electrically adjustable throttle valve over a comparatively larger range of values for various return pressure values, while simultaneously the advantageous precision of the injector connected to the first end remains secured when adjusting / regulating the return pressure to a nominal return pressure of the respective injector type. The device described here for adjusting the return pressure in this way is suitable for a variety of different types of injectors or generations of injectors, even if they require / require different return pressures. For example, with a variety of different types of electrically adjustable throttle valves, the adjustable / adjustable back pressure can be varied over a range of values from 0 bar to 10 bar. The described way of implementing the device for adjusting back pressure thus eliminates the traditional disadvantage that, until then, a specific device had to be used for each type of injector and for each generation of injectors, which had the valves specifically designed mechanical pressure retainers. An operator of the device described here for adjusting back pressure, therefore, does not need several devices for different types of injectors or injector generations. Accessories can also be saved using the device described here for adjusting back pressure. The operator thus saves money, storage space in the workshop and also does not waste preparation time (to equip the device he uses with the correspondingly suitable accessory).

[0006] The electrically adjustable throttle valve can for example be a Common-Rail pressure regulating valve or a Diesel-Common-Rail pressure regulating valve. Alternatively, the electrically adjustable throttle valve can also be a high pressure injection valve or a high pressure gasoline injection valve. The valve types described here are economical actuators. In addition, the valve types described here can be safely used as an electrically adjustable throttle valve together with an economical standard pressure sensor (from the automotive vehicle sector).

[0007] In particular, the device may have a control, which is designed, to emit at least one control signal with modulated pulse width for the pulsed control of the Common-Rail pressure regulating valve or Diesel-Common regulating valve -Rail or high pressure injection valve or high pressure gasoline injection valve. As a result, the types of valves listed here can also be used for reliable adjustment / regulation of back pressure in the low pressure range.

[0008] Preferably the device also comprises a pressure sensor and / or temperature sensor fixed between the first end of the return tube and the electrically adjustable throttle valve on the return tube. Due to the fact that the device for adjusting the back pressure is equipped with a pressure sensor that makes it possible to regulate the back pressure by means of the electrically adjustable throttle valve through “choke”, so that the back pressure increases at least between the first end of the return tube and the electrically adjustable throttle valve inside the return tube, until a target nominal return pressure is / is reached. A dynamic pressure occurring between the first end of the return pipe and the electrically adjustable throttle valve can be registered via the pressure sensor and used for corresponding adjustment of the electrically adjustable throttle valve. Further use of the temperature sensor also allows for consideration of thermodynamic influences.

[0009] The advantages previously described are also realized in a return block for injectors with at least two such devices for adjusting the return pressure. The return block can also have at least one control, which is designed to emit at least one control signal with modulated pulse amplitude for the pulsed control of at least one assigned Common-Rail pressure regulating valve or regulating valve. Diesel-Common-Rail pressure valve or high pressure injection valve or high pressure gasoline injection valve.

[0010] Also a measuring device for measuring injected volumes and / or measuring return volumes for at least one injector with at least one such device for adjusting back pressure, or a corresponding return block, and at least one injection volume sensor and / or return volume sensor, by means of which an injection volume and / or the return volume flowing through the return tube are measurable, brings about the advantages described above.

[0011] Correspondingly, the advantages described above are also brought about by means of a test stand for at least one injector with a corresponding measuring device for measuring injection volumes and / or measuring return volumes.

[0012] In addition, an execution of a corresponding process for adjusting the back pressure in at least one injector can achieve the advantages described above. It is specifically pointed out that the process for adjusting back pressure according to the forms of execution described above can continue to be developed. Brief Description of Drawings

[0013] Other features and advantages of the present invention are explained below by means of the figures. They show: Figure 1 a schematic representation of an embodiment of the device for adjusting back pressure; Figure 2 is a schematic representation of an embodiment of the return block; and Figure 3 a flowchart to explain a way of executing the process for adjusting the back pressure in at least one injector. Modalities of the invention

[0014] Figure 1 shows a schematic representation of an embodiment of the device for adjusting back pressure.

[0015] The device 10 for adjusting the back pressure represented schematically in figure 1 is applicable together with / usable for analysis / verification of an injector 12. By injector 12 can be understood a Common-Rail injector or an injection valve. As explained in more detail below, the device 10 for adjusting back pressure is usable with a variety of different types of injectors 12 (or different generations of injectors 12).

[0016] The device 10 for adjusting the return pressure has a return pipe 14. A return exhaust opening 12a from the injector 12, from which a return volume 16 of the injector 12 comes out of the injector 12, is (directly or indirectly) connectable / connected at a first end 14a of the return tube 14, so that the return volume 16 of the injector 12 flows from the first end 14a of the return tube 14 to a second end 14b of the tube return 14. As an alternative for direct connection of the return exhaust opening 12a at the first end 14a of the return pipe 14, in which the return exhaust opening 12a contacts the first end 14a of the return pipe 14, the return exhaust opening 12a can also be connectable / connected via at least one connecting component at the first end 14a of the return pipe

14. (A connection of an injection port 12b of the injector 12, through which an injection volume 18 of the injector 12 escapes from the injector 12, to the return tube 14 does not occur.)

[0017] The device 10 for adjusting the back pressure also comprises an electrically adjustable throttle valve 20, by means of which a back pressure is adjustable at least between the first end 14a of the return tube 14 with the connected injector 12 and the electrically adjustable throttle valve 20 on the return pipe 14. (The return pressure thus occurs as a set pressure between the injector 12 and the electrically adjustable throttle valve 20). The use of the electrically adjustable throttle valve 20 allows high precision when adjusting / regulating the back pressure. In particular, the back pressure can be reliably adjusted / regulated equal to a desired / specified nominal return pressure. It is also generally possible to adjust the return pressure (at least between the first end 14a of the return pipe and the electrically adjustable throttle valve 20) by means of the electrically adjustable throttle valve 20 on the return pipe 14 optionally for any return pressure value in a range with at least two different return pressure values. For this reason, the device 10 for adjusting the back pressure can also be used for different types of injectors and different generations of injectors, even when their intended / specified nominal return pressures differ from each other. Using the device 10 for adjusting the return pressure therefore provides the advantages explained above for reducing costs, saving preparation time and reducing the space required.

[0018] Preferably, the device 10 for the return pressure adjustment also comprises a pressure sensor 22 fixed between the first end 14a of the return tube 14 and the electrically adjustable throttle valve 20 on the return tube 14. In this case, it is also possible to adjust the back pressure by means of an interaction of the electrically adjustable throttle valve 20 and the pressure sensor 22. In addition, the device 10 for adjusting the back pressure can also comprise a temperature sensor (not shown in figure 1).

[0019] The electrically adjustable throttle valve 20 can be, for example, a Common-Rail pressure regulating valve (or a Diesel-Common-Rail pressure regulating valve). Although a pressure regulating valve (Diesel) -Common-Rail (as a proportional hydraulic valve) is designed for comparatively high pressures (according to the type between 1800 bar and 2500 bar), it is by means of a pulsed control pressure regulating valve (Diesel) - Common-Rail with pulse amplitude modulation also possible to cause a range of nominal return pressure values (at least between the first end 14a of the return tube and the throttle valve 20 electrically adjustable) inside the return tube 14. In this way, even return pressures in the low pressure range (between 0 bar to 10 bar) occur reliably and can be respected. Therefore, preferably a control 24 of the device 10 for the return pressure adjustment is designed to emit at least one control signal 26 with pulse amplitude modulated for the pulsed control of the pressure regulating valve (Diesel) -Com- -Rail.

[0020] It is also advantageous when the electrically adjustable throttle valve 20 is a high pressure injection valve (or a high pressure gasoline injection valve). To adjust / regulate the back pressure the high pressure (gasoline) injection valve can be controlled / will be controlled by control 24 by means of at least one control signal 26 (for example, a simple square wave) with modulated pulse amplitude. A high-pressure (gasoline) injection valve control using complex control signals, which requires a complex final phase using complex control signals, is not necessary.

[0021] The previously enumerated execution examples for the electrically adjustable throttle valve 20 allow for a pressure adjustment / pressure regulation without a complicated control effort and without high additional costs. This also causes a significant reduction in effort in the care of the product during the operation of the device 10 for adjusting the back pressure.

[0022] In an evolution of the device 10 for the return pressure adjustment (as a measuring device for the measurement of the injection volume and / or return volume) can be developed in the device 10 for the return pressure adjustment plus one injection volume sensor and / or return volume sensor 28, by means of which the injection volume 18 and / or the return volume 16 flowing through the return tube 14 are measurable. The device 10 for adjusting back pressure is therefore usable in several ways. The device 10 for adjusting the back pressure can for example be part of a test stand.

[0023] Figure 2 shows a schematic representation of a form of execution of the return block.

[0024] The return block shown schematically in figure 2 is usable for analysis / verification of several injectors 12. For this, the return block has several devices 10 for adjusting the return pressure. Each of the devices 10 for adjusting the back pressure comprises the components of the performance described above. As an optional development, each device 10 for the back pressure adjustment each has a filter 30 and each one a temperature sensor 32. Each of the devices 10 for the back pressure adjustment is designed for the adjustment / regulation of the return pressure for each return pressure value in a range of values with at least two different return pressure values, and the devices for the return pressure adjustment can simultaneously adjust / regulate different return pressures in its respective return tube 14 (at least between the first end 14a of the respective return tube and the respective electrically adjustable throttle valve 20). The return block in figure 2 in this way is simultaneously usable for different types of injectors and different generations of injectors.

[0025] Preferably, the return block also has at least one control 24, which is designed to emit at least one control signal 26 with pulse amplitude modulated for the pulsed control of at least one pressure regulating valve. mon-Rail or Diesel-Common-Rail pressure regulating valve or high pressure injection valve or assigned high pressure gasoline injection valve. As also shown in figure 2, the return block can also be used as a measuring device for measuring the injection volume and / or measuring the return volume (or as a test support).

[0026] The ways in which device 10 for adjusting the back pressure and the return block described above make it possible to adjust the pressure / regulate the active pressure universally through the use of usual automotive components instead of traditional industrial components. This also contributes to the reduction of costs in carrying out the forms of execution.

[0027] The forms of execution described above enable high precision in the adjustment / regulation of return pressures (without significant control). This contributes to the increase in measurement accuracy when measuring the injection volume 18 and / or the return volume 16 and to the increase in the information value of the measurement results obtained.

[0028] All the forms of execution described above make it possible to give up accessories, so that additional costs for accessories can be saved and a traditional effort on the part of developing product care is discarded. Preparation times can also be saved and a workshop location that is no longer needed as a deposit for accessories can be used in another way.

[0029] Figure 3 shows a flowchart to explain a way of executing the process for adjusting back pressure in at least one injector.

[0030] In a step of the S1 process a back pressure is at least adjusted between a first end of the return tube, in which an injector return emptying opening is connected in such a way that an injector return volume flows from a first end of the return pipe to a second end of the return pipe, and the valve on the return pipe. For this purpose, the return pressure is adjusted by means of an electrically adjustable throttle valve at least between the first end of the return pipe and the electrically adjustable throttle valve within the return pipe. In a line cable between the injector and the electrically adjustable throttle valve, the back pressure is configured as a defined pressure.

[0031] Preferably the return pressure for a first type of injector is set to a first return pressure value at least between the first end of the return pipe and the electrically adjustable throttle valve inside the return pipe, while for another / second type of injector that differs from the first type the return pressure at least between the first end of the return pipe and the electrically adjustable throttle valve inside the return pipe is set to another / second return pressure value different from the first return pressure value. This can also occur when, in different types / generations of injectors, a nominal return pressure of the respective types / generations is simultaneously simultaneously adjusted.

[0032] Optionally, one process step S2 can be simultaneously or overlapping in time with process step S1, in which an injection volume and / or return volume of at least one injector are measured. The process described here can thus also be termed as a process for measuring injection volume and / or measuring return volume in at least one injector.

Claims (13)

1. Device (10) for adjusting the back pressure for an injector (12) with: a return tube (14) with a first end (14a), in which it is possible to connect a return exhaust port (12a) injector (12) directly or indirectly in such a way that a return volume (16) from the injector (12) can flow from the first end (14a) of the return tube (14) to a second end (14b) of the return tube (14); and at least one valve (20), whereby a return pressure is adjustable at least between the first end (14a) of the return tube (14) connected with the injector (12) and the valve (20) inside the return tube (14); characterized by the fact that the device (10) presents as an electrically adjustable throttle valve (20), and the return pressure is adjustable by means of the electrically adjustable throttle valve (20). at least between the first end (14a) of the return tube (14) with the injector (12) connected and the electrically adjustable throttle valve (20) inside the return tube (14). 2. Device (10) for adjusting the back pressure according to claim 1, characterized by the fact that by means of the electrically adjustable throttle valve (20) the return pressure is adjustable at least between the first end (14a) of the return tube (14) and the electrically adjustable throttle valve (20) inside the return tube (14) optionally for all return pressure values in a range of values with at least two different back pressure values. 3. Device (10) for adjusting back pressure according to claim 1 or 2, characterized by the fact that the electrically adjustable throttle valve (20) is a common-rail pressure regulating valve or a Diesel-Common-Rail pressure regulating valve. 4. Device (10) for adjusting the back pressure according to claim 1 or 2, characterized by the fact that the electrically adjustable throttle valve (20) is a high pressure injection valve or a pressure valve injection of high pressure gasoline. 5. Device (10) for adjusting back pressure according to claim 3 or 4, characterized by the fact that the device (10) has a control (24), which is designed to emit at least one signal control unit (26) with modulated pulse amplitude for pulsed control of the Common-Rail pressure regulating valve or Diesel-Common-Rail pressure regulating valve or high-pressure injection valve or high-pressure gasoline injection valve . 6. Device (10) for adjusting back pressure according to any one of the preceding claims, characterized in that the device (10) comprises a pressure sensor (22) and / or a temperature sensor (32) fixed between the first end (14a) of the return pipe (14) and the throttle valve (20) electrically adjustable in the return pipe (14). 7. Return block for injectors (12) characterized by the fact that it has at least two devices (10) for adjusting the return pressure as defined in any one of claims 1 to 4 and 6. 8. Return block according to claim 3 and / or 4 and claim 7, characterized by the fact that the return block has at least one control (24), which is designed to emit at least one control signal (26) with modulated pulse amplitude for pulsed control of at least one pressure regulating valve Common-Rail or Diesel-Common-Rail pressure regulating valve or high-pressure injection valve or assigned high-pressure gasoline injection valve. 9. Measuring device characterized by the fact that it is for measuring the injection volume and / or measuring the return volume for at least one injector (12) with: 10. at least one device (10) for adjusting back pressure as defined in any one of claims 1 to 6 or a return block as defined in claim 7 or 8; and at least one injection volume sensor and / or return volume sensor (28), by means of which it is possible to measure an injection volume (18) and / or a return volume (16) flowing through the injection tube. return (14) assigned. 11. Test stand characterized by the fact that it is for at least one injector (12) with a measuring device to measure the injection volume and / or measure the return volume as defined in claim 9. 12. Process for adjusting the back pressure in at least one injector (12) with the step: adjust a back pressure by means of at least one valve (20) at least between a first end (14a) of a pipe return (14), in which a return exhaust opening (12a) of the injector (12) is connected in such a way that a return volume (16) of the injector (12) from the first end (14a) of the return pipe (14) flows to a second end (14b) of the return tube, and the valve (20) inside the return tube (14); characterized by the fact that the return pressure is adjusted (S1) by means of an electrically adjustable throttle valve (20) as a valve (20) at least between the first end (14a) of the return pipe (14) with the injector (12) connected and the throttle valve (20) electrically adjustable inside the return tube (14). 13. Method for adjusting back pressure according to claim 11, characterized in that for a first type of injector (12) the back pressure is set at least between the first end (14a) of the return tube ( 14) and the choke valve (20) electrically adjustable inside the return tube (14) at a first return pressure value and for a second type of injector (12) different from the first type the pressure is adjusted at least between the first end (14a) of the return tube (14) and the throttle valve (20) electrically adjustable inside the return tube (14) at a second return pressure value different from first back pressure value.