WO2003054491A2

WO2003054491A2 - Measuring rod

Info

Publication number: WO2003054491A2
Application number: PCT/EP2002/014604
Authority: WO
Inventors: Peter Steinleitner; Dieter Schneegans; Rudolf Gattringer
Original assignee: Schneegans Gmbh
Priority date: 2001-12-20
Filing date: 2002-12-19
Publication date: 2003-07-03
Also published as: DE10163128A1; AU2002366871A1; WO2003054491A3

Abstract

The invention relates to a measuring rod, particularly an oil level plunger, comprising a rod-shaped element for plunging into a vessel containing a medium, particularly oil. A grip part is arranged at one end of the inventive measuring rod while a measuring tongue is disposed at the other end thereof. The measuring tongue is provided with at least one measuring device for detecting the status of the medium while the grip part comprises a display device displaying the variables detected by the measuring device.

Description

dipstick

The invention relates to a dipstick for immersion in a medium, in particular oil, containing container, in particular oil dipstick, with a stabformigen element, at one end of a handle and at the other end of a measuring tongue is arranged.

Measuring rods are used in different embodiments and made of different materials, which are particularly based on the application, for measuring the liquid level in containers. For example, oil dipsticks are used in engines to check the oil level in the engine housing and gearbox.

As described, for example, in DE 196 01 732 C2, such measuring rods usually consist of a rod-shaped element made of metal or plastic, on whose end immersed in the container a measuring tongue with marking lines is attached. The level measurement is carried out by first removing the measuring rod from the container and cleaning it, then returning it to the container and then removing it from the container to determine the filling level. The wetting on the measuring tongue indicates the level of the medium in the container.

EESTÄTiGUNGSKOP.E This measurement is time consuming and involves the risk of contamination. From DE 44 20 651 A1, therefore, a device for controlling the liquid level in a container is known which has an incandescent lamp and an photoelectronic element at its lower end immersed in the container. The measurement of the liquid level in the container is achieved by impinging light from the light source onto the photoelectronic element as a function of the wetting of the photoelectronic element with the liquid in the container. A light-emitting diode indicates whether the photoelectronic element is wetted by the liquid.

Further, it is known in the automotive field to determine by means of sensors, the oil level in the oil sump of an engine and / or transmission and display in a display device in the cockpit of the vehicle. However, this solution is extremely cost-intensive, so that an application has so far been realized only in vehicles of the highest price sector.

In addition to measuring the oil level in engine casings and gearboxes, there is a need to check the condition of the oil. The state of the oil is dependent on the current oil temperature, the maximum oil temperature reached in the past, the contamination by suspended particles, such as abrasion or impurities, and possibly the achievement of a minimum temperature. By determining the state of the oil, a reliable statement can be made as to whether the engine and / or transmission oil must be replaced before starting up an engine.

The present invention is therefore based on the object of providing a measuring rod with which the parameters of a medium in a container are determined and displayed quickly and without the risk of contamination, which allow conclusions about the usability of the medium. simultaneously should the measuring rod against high temperatures and bending stresses be resistant and inexpensive to produce.

In the case of a measuring rod of the type mentioned in the introduction, this object is achieved according to the invention by providing at least one measuring device for determining the condition of the medium on the measuring tongue and at least one indicating device representing the values determined by the measuring device. In the exemplary application of the use of the measuring rod for controlling engine or transmission oil in a motor vehicle, it is possible to decide directly when opening the hood, whether the oil must be changed because, for example, the maximum permissible operating temperature has been exceeded or the oil is contaminated. The state of the oil is shown on the handle in a display device.

In development of this idea, the measuring device is used in addition to determining the level of the medium. For example, it is thus possible to read the amount of oil and its condition in the engine compartment, without the oil dipstick this must be repeatedly pulled out of the oil sump and cleaned. This significantly increases the comfort of oil level measurement and avoids the risk of contamination.

Preferably, the measuring device is a temperature measuring device which determines the current temperature of the medium. The viscosity and wetting properties of various media, such as oil, are highly dependent on the operating temperature. To assess the state of oil, for example in an engine or a transmission, it is therefore necessary to determine the current temperature of the oil. At the same time it can be ensured in this way that before an oil change or other maintenance work, the risk of scalding or burns is avoided because the oil temperature and so that the temperature of the engine in the engine compartment itself can be read. Furthermore, the measuring device also determines the maximum temperature of the medium that has been reached, so that advantageously it can additionally be ascertained whether the permissible upper operating temperature of the medium, for example engine oil, has been exceeded. Based on this data, it can be decided whether the medium needs to be replaced or whether operation with this medium can continue.

According to a preferred embodiment of the invention, it is provided that the measuring device has at least one heat-conducting element connected to the display device. In order to display the current temperature or the maximum temperature reached of the medium in the display device, it is necessary to conduct the heat via a thermally conductive element from the measuring device to the display device.

The heat-conducting element can be realized in a particularly simple and cost-effective manner if one or more copper wires are provided, which extend from the measuring tongue along the rod-shaped element to the grip piece. The temperature of the medium, for example engine oil, is passed through the copper wires from the measuring tongue with the measuring device to the indicator of the handle via convection.

It is preferred that the display device has a temperature-discoloring element as a function of the temperature. The temperature of the medium can be perceived on the display device of the handle at a glance by the discoloration of the display element. Depending on whether the current temperature or the maximum temperature reached in the past is to be displayed, a reversibly or irreversibly discoloring element is to be provided in the display device. According to a further embodiment of the invention, an optical conductor is arranged between the measuring device and the display device. The optical conductor makes it possible, regardless of pulling out the measuring rod on the container containing the medium to check the level of the medium and its translucency. For example, a heavily soiled by abrasion engine oil contains many suspended matter, which reduce the light transmittance of the engine oil, so that an exchangeable engine oil can be distinguished from a new engine oil based on the light transmittance.

Preferably, the rod-shaped element has a strand of glass fiber, which is coated with a plastic. The glass fiber strand is not only an optical conductor, but also significantly improves the material properties of the measuring rod compared to those made of metal. So a fiber optic gauge is not only lighter, but also more resistant to high temperatures and bending stresses.

In a further development of the concept of the invention, it is provided that at least one photoelectric element is provided on the measuring device. By means of the photoelectric element, it is possible to measure, for example, by means of light incident, for example, over the optical conductor, in how far the photoelectric element is mixed with the medium, e.g. Engine oil, is wetted to determine the level of the medium. At the same time in this way the light transmission of the medium to be controlled and thus its state can be measured.

Alternatively or additionally, it is possible to provide at least one light source on the measuring device. The light source can be used to determine the level of the medium in the container and to test the light transmittance of the medium regardless of light, the permeability of the medium are used independently of light, which is incident for example via the optical conductor in the container.

The results of the measurements of the measuring rod according to the invention can then be read in a particularly convenient manner if the display device is connected to a further display which, for example, is located inside a vehicle, ie. H. in the cockpit, is arranged. The need for an oil change can be displayed to a driver regardless of the distance covered since the last oil change, depending on the actual state of the engine oil. Even the tedious opening of the engine compartment to check the oil level when refueling the vehicle can be omitted in this way.

In addition to the use of the dipstick as an oil dipstick in motor vehicles and a use for controlling the level and / or the condition of other operating fluids in vehicles or other facilities is possible.

According to the invention, a dipstick for immersion in a container containing a medium, in particular oil, in particular a dipstick, with a stabformigen element, at one end of a handle and at the other end a measuring tongue is arranged, be provided in the handle with a vent line to avoid over or under pressure in the dipstick receiving channel of the container when the dipstick is inserted into or withdrawn from the channel. The vent line is in communication with both the channel and with the environment and may, for example, be closed by a gas-permeable membrane in the handle.

Alternatively or additionally, according to an embodiment of the invention, it is provided that on the handle opposite the measuring tongue a stop member is slidably mounted with a seal in the axial direction of the measuring rod, wherein the seal is hermetically sealing by a displacement of the handle relative to the stop member to the measuring rod at least partially receiving channel of the container. The channel of the container is thus only then closed by the dipstick when the handle is moved relative to the stop member. An overpressure building up during the insertion of the measuring rod into the channel can thus escape until the channel is sealed by displacing the grip. In the same way, when the measuring rod is pulled out, a negative pressure in the channel can escape from the channel if, before pulling out, the seal is released from the channel by displacement of the handle relative to the stop member.

In a further development of this inventive idea, the grip piece has a conical region, which surrounds the elastically expandable seal at least in regions. By moving the stop member relative to the handle, the seal is thus expandable from a contracted, not applied to the channel state such that it bears sealingly against the channel.

In addition, a spring element may be provided on the stop member, which is arranged at least partially between the elastic seal and the conical portion of the handle. The spring element clamps the stop member on the handle so firmly that during insertion of the measuring rod into the channel, the stop member is held on the handle so that the elastic seal is not hermetically sealingly applied to the pipe. Only when the stop member rests against the funnel-shaped end of the channel, the spring element is widened by further pressure on the handle so that the handle can be moved relative to the stop member. The spring element therefore fulfills a stop function, since it only the handle releases when the stop member firmly abuts the funnel-shaped end of the channel.

For holding the measuring rod in the channel may be provided on the handle and / or in particular on the stop member, a retaining groove or a retaining groove (locking projection) for engagement with a retaining groove or a retaining groove on the inside of the channel. The stop member is preferably secured by the retaining groove engaging in the retaining groove in the channel, that the handle of the measuring rod can be moved relative to the stop member. When the retaining groove engages the retaining groove, a click is heard or felt in the grip so that a user recognizes when the dipstick is fully and sealed inserted into the channel.

Further developments, advantages and applications of the invention will become apparent from the following description of exemplary embodiments and the drawings. All described and / or illustrated features alone or in any combination form the subject matter of the invention, regardless of their combination in the claims or their dependency.

Show it:

1 shows the handle of the measuring rod according to a first embodiment of the invention in partial sectional view,

2 shows the handle of the measuring rod according to a second embodiment of the invention in partial sectional view, Fig. 3 shows the handle of the measuring rod according to a third embodiment of the invention in a perspective view and

Fig. 4, the handle of Fig. 3 with separate stop member and seal.

In the figures, only the upper end with the handle 2 is shown by the measuring rod 1, while the handle 2 remote from the end of the measuring rod 1 with the immersed in an oil tank or the like measuring tongue is not shown.

The measuring rod 1, for example, formed as a flat or round rod made of fiberglass, metal or the like is firmly connected to the handle 2, for example by gluing, welding or the like. The measuring rod 1 can, as shown in the figures, in a channel 3 of a container for z. As oil can be introduced. The channel 3 is provided with a funnel-shaped end 4, in which the measuring rod 1 can be used with the handle.

In the embodiment shown in Figure 1, a sealing ring 5 is provided in the funnel-shaped end 4 of the channel 3, through which the handle 2 of the measuring rod 1 is hermetically sealed against the channel 3. Next, a vent line 6 is provided in the handle 2, the first, in the figure lower end with the channel 3 is in communication. This lower end of the vent line 6 is arranged below the seal 5. The other end of the vent line 6 is closed by a gas-permeable membrane 7, which, however, prevents the ingress of dirt or the like in the vent line 6. In the embodiment shown in FIG. 1, the membrane 7 is fastened in the grip piece 2 via a retaining ring 8.

Upon insertion of the measuring rod 1 into the channel 3, an overpressure building up in the channel 3 via the vent line 6 can be eliminated in this way. - lo ¬

chen, so that the measuring rod 1 can not be pressed by the pressure from the channel 3. In the same way, a pressure compensation via the vent line 6 takes place even when pulling out the measuring rod 1 from the channel 3.

In the embodiment shown in Figure 2, the handle 2 is connected to a stop member 9 which is slidably mounted by the distance s in the axial direction of the measuring rod 1 on the handle 2 between two abutment surfaces. For this purpose, the handle 2 can be injection-molded into the abutment part 9, for example by means of assembly injection molding. On the side facing the channel 3 of the stop member 9, a seal 10 is provided, which is for example sprayed onto the stop member 9. The elastic seal 10 is not firmly connected to the handle 2, but rests only on a conically tapering portion 11 of the handle 2.

On the outer circumference of the stop member 9 is preferably a retaining groove (locking projection) 12 is formed, which engages in the position shown in Figure 2 of the stop member 9 in a circumferential retaining groove 13 on the inside of the funnel-shaped end 4 of the channel 3. The stop member 9 is releasably held in this way in the funnel-shaped end 4 of the channel 3.

During insertion of the measuring rod 1 into the channel 3, an overpressure building up in the channel 3 can escape through the interspace formed between the abutment part 9 and the funnel-shaped end 4. In the same way, a pressure equalization can take place even when pulling out the measuring rod 1 from the channel 3.

The measuring rod 1 can be hermetically sealed against the channel 3 by the handle 2 is pressed from the position shown in Figure 2 by the distance s further into the stop member 9. The conical portion 11 of the handle 2 In this case, the elastic seal 10 expands so that it rests against the inner wall of the funnel-shaped end 4 of the channel 3. In this way, the channel 3 is closed by the measuring rod 1 substantially liquid and gas-tight. When pulling out the measuring rod 1 from the channel 3, the handle 2 is displaced relative to the stop member 9 by the distance s in the position shown in Figure 2. The stop member 9 is initially held by the engaging groove 13 in the retaining groove 12 in the funnel-shaped end 4 of the channel 3. Due to the axial displacement of the gripping piece 2 relative to the abutment part 9, the elastic seal 10 can pull together again so far that it no longer rests against the inside of the funnel-shaped end 4 of the channel 3. It can now take place a pressure equalization between the channel 3 and the environment. By further pulling on the handle 2 of the measuring rod 1, the connection of the stop member 9 with the channel 3 via the retaining groove 12 and the retaining groove 13 is released, so that the handle 2 can be pulled together with the stop member 9 from the channel 3.

In this inventive design of the handle 2 of the measuring rod 1, the seal seals 10 until the last moment of Eindrückvorganges the channel 3, while the seal 10 is immediately relieved when pulling the measuring rod 1. In this way, a possible overpressure or a vacuum in the channel 3 can be rapidly reduced.

FIGS. 3 and 4 show a further embodiment of the measuring rod, in which an annular spring 14 with a plurality of spring tongues is provided on the abutment part 9 in the region of the elastic seal 10. The spring 14 is arranged on the conical portion 11 of the handle 2 facing side of the stop member 9. At least when the spring 14 is slid over the diameter-expanded portion of the handle 2, it is under bias, so that the stop member 9 is held on the handle 2. As a result, a displacement of the handle 2 relative to the stop member 9 is only possible when inserting the measuring rod 1 in the channel 3 when the stop member 9 abuts the funnel-shaped end 4 of the channel 3. Only when further pressure is exerted on the handle 2 in the position shown in Figure 3, this can be further pressed by the distance s in the stop member 9 until the retaining groove 12 engages in the retaining groove 13. A snap-in click indicates to the user that the dipstick 1 is sealed in the channel 3.

Here, the elastic seal 10 is radially expanded by the spring 14, which slides on the conical portion 11 of the handle 2, so that the channel 3 is hermetically sealed.

When pulling out the measuring rod 1, the stop member 9 is first held by the retaining groove 12 and the retaining groove 13 in the funnel-shaped end 4 of the channel 3, while the spring 14 slides on the handle 2 and contracts. In the same way, the elastic seal 10 contracts to allow pressure equalization between the channel 3 and the environment. Only then is the stop member 9 released from its latching with the channel 3 and pulled out of the funnel-shaped end 4 of the channel 3. LIST OF REFERENCE NUMBERS

1 dipstick

2 handle

3 channel

4 funnel-shaped end

5 seal

6 vent line

7 membrane

8 retaining ring

9 stop part

10 elastic seal

11 conical area

12 retaining groove (locking projection)

13 holding groove

14 spring

s displacement path

Claims

claims:

1. dipstick, in particular dipstick, for immersion in a medium, in particular oil, containing container with a stabformigen element, at one end a handle (2) and at the other end a measuring tongue is arranged, characterized in that at the measuring tongue at least one measuring device for determining the state of the medium and on the handle (2) at least one of the determined by the measuring device values representing display device are provided.

2. Measuring rod according to claim 1, characterized in that the measuring device is also designed to determine the level of the medium.

3. dipstick according to claim 1 or 2, characterized in that the measuring device is a temperature measuring device.

4. Measuring rod according to one of the preceding claims, characterized in that the measuring device has at least one connected to the display device heat-conducting element.

5. A dipstick according to claim 4, characterized in that the heat-conducting element comprises one or more copper wires extending ge of the Meßzun- along the rod-shaped element to the handle (2).

6. Measuring rod according to one of the preceding claims, characterized in that the display device has a color as a function of the temperature-discoloring element.

7. Measuring rod according to one of the preceding claims, characterized in that an optical conductor is arranged between the measuring device and the display device.

8. Measuring rod according to one of the preceding claims, characterized in that the rod-shaped element has a strand of glass fiber, which is coated with a plastic.

9. Measuring rod according to one of claims 7 or 8, characterized marked, that at least one photoelectric element is provided on the measuring device.

10. Measuring rod according to one of the preceding claims, characterized in that at least one light source is provided on the measuring device.

11. Measuring rod according to one of the preceding claims, characterized in that the display device is connected to a further display, in particular in a vehicle interior.

12. Measuring rod according to one of the preceding claims, characterized in that in the handle (2) a vent line (6) is provided which connects a channel (3) of the container containing the medium with the environment.

13. Measuring rod according to claim 12, characterized in that in the handle (2) a gas-permeable, the vent line (6) occluding membrane (7) is arranged.

14. Measuring rod according to one of the preceding claims, characterized in that on the handle (2) a stop member (9) with a seal (10) in the axial direction of the measuring rod (1) is displaceably mounted, and that the seal (10) a displacement of the handle (2) relative to the stop member (9) on the measuring rod (1) at least partially receiving channel (3) of the container is hermetically sealing applied.

15. A measuring rod according to claim 14, characterized in that the handle piece (2) has a conical region (11), which surrounds the elastically aufweit- bare seal (10) at least partially, so that by moving the stop member (9) relative to the handle (2), the seal (10) is expandable.

16. A dipstick according to claim 15, characterized in that between the handle (2) and the elastic seal (10) one with the stop member

(9) connected spring (14) is provided which rests at least partially under bias on the handle (2).

17. Measuring rod according to one of claims 12 to 16, characterized marked that on the handle (2) and / or on the stop member (9) has a retaining groove or a retaining groove (12) for engagement with a retaining groove or a retaining groove (12). 13) is provided on the inside of the channel (3).