EP2616665B1 - Hydraulic temperature compensator and hydraulic lift transmitter - Google Patents

Description

The invention relates to a hydraulic temperature compensator, in particular for a hydraulic Hubübertrager. The invention further relates to a hydraulic lifting transformer with such a hydraulic temperature compensator, in particular an injector.

To introduce a desired amount of fuel in any combustion processes injection usually (injectors) are necessary, by means of which an amount of fuel can be metered. Since many combustion processes occur with the direct injection of high-pressure fuel, often very fast-acting actuators are used, which drive injectors. This means that an actuator generates a stroke which actuates, for example, an injector needle, which in turn opens a valve and releases a fuel at predetermined time intervals and in adjustable flow rates for a combustion process. Combustion air is supplied separately in this case.

Injectors for high-pressure direct injection often use fast actuators, such as "Piezo Multilayer Actuators" (PMA). These are solid state actuators whose central element consists of a plurality of piezoelectric layers. Furthermore, so-called magnetostrictive solid-state actuators are known, which exploit a magnetic mechanical effect for the generation of a stroke. For the generation of a stroke is important that such solid state actuators have too low a stroke to open an injector needle so far that the desired amount of fuel is introduced. Especially with gas injectors that require a longer stroke than injectors that dose liquid fuel, this becomes a major problem. This This results in only constructions with a stroke translator being considered.

In the case of the use of hydrogen as fuel, it is aggravating that the small and light hydrogen molecule easily diffuses through non-metallic elements such as rubber membranes. Thus, the selection of a suitable Hubübersetzers to a central problem in the construction of injectors. This is also due to the fact that a translator determines many characteristics of an injector and, unlike an actuator, can be reconfigured constructively.

In previous solutions to problems is a stroke magnification by mechanical translation or by partially non-metallic sealed hydraulic translation. Mechanical translators using, for example, a mechanical lever are generally susceptible to wear and unwanted vibration. This is especially true when an idle stroke between the actuator and translator is required, for example, to prevent leakage that could occur with thermal length change due to heating. As a result, an impact of the actuator, for example, take place on a nozzle needle, whereby the injector is adversely affected. Uneven injection and unsafe opening and closing characteristics are the result. An idle stroke between the actuator and translator is also undesirable because the Aktorauslenkung remains unused to the contact with the nozzle needle.

An increase in the stroke of an actuator with a ratio of less than 1: 2 is often realized with mechanical levers. For injectors for diesel engines, for example, the mechanical transmission ratio can be 1: 1.6. Gas injectors typically require larger ratios. In gas injectors usually hydraulic translators, also referred to as hydraulic levers used. For example, CNG direct injection (compressed natural gas) uses a 1: 6 stroke ratio.

By using a hydraulic translator, the idle stroke can be avoided, so that the chain of action between the actuator and the nozzle needle is constantly present. This is reflected directly in the structural design. In other words, the Aktorauslenkung is exploited to a greater extent from the injector and implemented.

A drawback in the prior art, for example in automotive engineering, is the wide temperature range to be observed, which may range from -40 ° C to + 150 ° C. This can result in significant volume changes when considering fluid volumes. Peak values can be significantly higher than 30% volume increase. For this reason, hydraulic stroke translators in most cases require connection to a reservoir.

In the German Offenlegungsschrift DE 10 2005 042 786 A1 For example, a fuel injector is disclosed that is equipped with a hermetically sealed hydraulic system. In this document so-called guided pistons are used. Such guided pistons require high mechanical precision in manufacturing and are very susceptible to wear.

Another example is from the DE 1032 1693 A1 known.

It is the object of the present invention to at least partially overcome the disadvantages of the prior art and in particular to provide a possibility for a particularly low-wear temperature compensation of a closed hydraulic system.

This object is achieved according to the features of the independent claim. Preferred embodiments are in particular the dependent claims.

• die Hydraulikkammer mittels einer berührungslos in eine Außenwand eingesetzten Innenwand gebildet wird,
• zwischen der Außenwand und der Innenwand eine Trennwand zur Bildung der ersten Teilkammer und der zweiten Teilkammer berührungslos eingesetzt ist und die Trennwand die mindestens eine Drosselstelle aufweist,
• die Innenwand, die Außenwand und die Trennwand jeweils einseitig offen sind und mit ihrer jeweiligen offenen Seite hermetisch an einem gemeinsamen Deckel befestigt sind und
• die gasgefüllte Kammer mittels einer Innenseite der Innenwand gebildet wird.

The object is achieved by a hydraulic temperature compensator, at least comprising a longitudinally expandable hydraulic chamber and a gas-filled chamber, which from the hydraulic chamber is at least partially surrounded, wherein the hydraulic chamber is divided into a first sub-chamber and a second sub-chamber, which are hydraulically connected to each other by means of at least one throttle point and wherein the second sub-chamber adjacent to the gas-filled chamber and wherein

• the hydraulic chamber is formed by means of an inner wall used without contact in an outer wall,
• a partition wall for forming the first sub-chamber and the second sub-chamber is inserted without contact between the outer wall and the inner wall and the partition wall has at least one throttle point,
• the inner wall, the outer wall and the partition wall are each open on one side and are hermetically fixed with their respective open side to a common cover, and
• the gas-filled chamber is formed by means of an inner side of the inner wall.

This embodiment according to the invention is particularly simple and robust to build. In addition, a deformation of the temperature compensator and a resulting pressure build-up in a rapid deformation can be achieved easily by a relative displacement of the lid.

When a temperature at the temperature compensator rises (typically slowly), a pressure of a liquid in the hydraulic chamber also rises slowly due to its thermal expansion. With regard to the slow rise in pressure, the first sub-chamber and the second sub-chamber are fluidically connected through the throttle point virtually unhindered. Due to the increase in pressure in the liquid and the consequent larger pressure difference between the second sub-chamber and the gas-filled chamber, the (inner) gas-filled chamber is compressed so that the liquid can expand and the pressure increase of the liquid is limited, in particular to a practically negligible level , This process is friction-free and therefore lock-free. In particular, the pressure limitation can also be used for fluidically connected hydraulic elements or devices with the hydraulic chamber, in particular with its first sub-chamber.

For fast processes in which the throttle point is permeable to the liquid to a small extent during an actuation interval, a pressure, in particular via the first sub-chamber, can be passed on essentially without loss, or, e.g. be constructed by a compression of the temperature compensator, essentially lossless and possibly passed on. The temperature compensator is thus particularly suitable for use in or with fast-switching Hubübertragern (hydraulic levers) and actuators.

The temperature compensator is largely frictionless and therefore operable without seal and allows both an effective temperature compensation and a largely lossless pressure transfer and / or pressure build-up. The temperature compensator also has a particularly compact design.

For example, the restriction may be configured as a fluid channel (e.g., in the form of a bore) having a suitably sized flow area.

It is an embodiment that the gas-filled chamber is an open chamber. For this purpose, the gas-filled chamber can be connected in particular via a passage opening to the surroundings of the temperature compensator. Alternatively, the gas-filled chamber may be hermetically sealed. In particular, the gas may be air, so the gas-filled chamber may be an air chamber.

The partition may be formed in particular rigid. The inner wall and the outer wall may in particular be longitudinally expandable (compressible / expandable).

The inner wall can also be described as integrated into the outer wall.

It is yet a further embodiment that the inner wall and / or the outer wall in each case in the form of an end open bellows, in particular metal bellows, are configured. The bellows has the advantage that in a longitudinal extension it is much easier to stretch (in particular compressible and re-expandable) than perpendicular to it and this deformability is easily achievable in terms of design technology. In addition, bellows are inexpensive to produce and easy to handle and fasten.

It is also an embodiment that the partition in the form of an open end (rigid) hollow cylinder (with any, advantageously circular, cross-section) is configured. This has the advantage that a volume in the first sub-chamber essentially depends only on a deformation of the outer metal bellows and a volume in the second sub-chamber essentially depends only on a deformation of the inner metal bellows and the two volumes only through the throttle point with each other in Active compound stand.

It is a development that the bellows and the partition are arranged concentrically to a common axis.

It is still an embodiment that the outer wall is hermetically fixed to the partition wall and the partition wall is hermetically fixed to the lid. The outer wall is thus indirectly attached to the lid. Alternatively, the outer wall and the partition wall may be individually (directly) hermetically attached to the lid.

It is also an embodiment that at least one compression spring element is accommodated in the gas-filled chamber. This provides the advantage that a (static) system pressure can be adjusted in the hydraulic fluid. Also, such a relationship between a pressure difference between the second sub-chamber and the gas-filled chamber on the one hand and a change in volume of the second sub-chamber is particularly precisely adjustable.

Since the gas-filled chamber is designed to be open to the outside, the spring force of the spring element can also by means of an actuating element projecting into the gas-filled chamber, e.g. a set screw, individually and subsequently adjustable. This allows the system pressure to be changed later.

It is also an embodiment that the hydraulic chamber has a unidirectional valve, in particular flutter valve, which allows a flow from the second sub-chamber into the first sub-chamber. As a result, a dead time between two compression phases of the temperature compensator can be shortened.

It is also an embodiment that the hydraulic chamber is filled with a substantially incompressible liquid, in particular with oil, in particular hydraulic oil, in particular free of bubbles. This can be achieved by a vacuum filling. So lift and / or pressure losses can be suppressed.

The object is also achieved by a hydraulic lifting transformer, at least comprising the hydraulic temperature compensator as described above, acting on the temperature compensator Hubaktor and another hydraulic chamber, which is fluidically connected to the first sub-chamber of the hydraulic chamber of the temperature compensator, wherein the further hydraulic chamber fluidly with a slidably mounted actuator is in communication. By means of the hydraulic temperature compensator can thermally induced Pressure fluctuations of a hydraulic fluid in the Hubübertrager are at least largely limited and so a switching accuracy can be increased. In addition, a pressure build-up or a pressure transfer can be made substantially lossless by the hydraulic lift transformer.

The hydraulic lift transformer can also be designed as a hydraulic lever. The hydraulic lift transformer can also be configured as a valve, in particular an injection valve.

In the event that in the hydraulic temperature compensator, the hydraulic chamber is formed by a non-contact used in an outer wall inner wall, between the outer wall and the inner wall, a partition wall for forming the first sub-chamber and the second sub-chamber is used without contact and the partition has the at least one throttle point in that the inner wall, the outer wall and the partition wall are each open on one side and are hermetically fixed with their respective open side to a common lid and the gas-filled chamber is formed by an inner side of the inner wall, the Hubaktor can be connected in particular to the lid. This allows a largely lossless stroke application to the hydraulic temperature compensator.

It is also an embodiment that the Hubaktor and the temperature compensator between two fixed bearings are supported. This makes the hydraulic temperature compensator particularly easy to use for pressure build-up.

It is also an embodiment that the stroke transformer is part of an injector. This improves a temperature-independent injection, in particular of fuel into a combustion chamber of an engine. The injector can be, for example, a liquid injector (for example a diesel, kerosene, LPG or gasoline injector) or a gas injector (For example, a hydrogen injector or natural gas injector).

The hydraulic lift transformer may be provided in particular for transmitting the Primärhubs the Hubaktors on an actuator.

The hydraulic lift transmitter may be a hydraulic lift converter. Alternatively, the hydraulic lift transformer may be a hydraulic Hubuntersetzer.

The Hubaktor, the inner wall, the outer wall and the partition can be arranged concentrically to each other.

Fig.1

zeigt als Schnittdarstellung in Seitenansicht ein hydraulisch angetriebenes Ventil mit einem erfindungsgemäßen thermischen Kompensator gemäß einer ersten Ausführungsform;

Fig.2

zeigt als Schnittdarstellung in Seitenansicht einen erfindungsgemäßen thermischen Kompensator gemäß einer zweiten Ausführungsform;

Fig.3

zeigt als Schnittdarstellung in Seitenansicht einen erfindungsgemäßen thermischen Kompensator gemäß einer dritten Ausführungsform.

In the following figures, the invention will be described schematically with reference to exemplary embodiments. In this case, the same or equivalent elements may be provided with the same reference numerals for clarity.

Fig.1

shows a sectional side view of a hydraulically driven valve with a thermal compensator according to the invention according to a first embodiment;

Fig.2

shows a sectional side view of a thermal compensator according to the invention according to a second embodiment;

Figure 3

shows a sectional side view of a thermal compensator according to the invention according to a third embodiment.

Fig.1 outlined a hydraulically driven valve 1, for example, an injector, in particular a fuel injector. The valve 1 has a solid-lifting actuator in the form of a piezoelectric actuator 2, which rests with its back on a bearing 3 and on its front side has a plunger 4. The plunger 4 is along a body axis or longitudinal axis L displaceable. The plunger 4 is articulated to a thermal compensator 5 according to a first embodiment.

The thermal compensator 5 has an outer wall in the form of a unilaterally open outer metal bellows 6. In the outer metal bellows 6 a smaller in length and diameter inner metal bellows 7 is used, which is also open at the end. Between the outer metal bellows 6 and the inner metal bellows 7 there is a partition wall 8 in the form of a rigid, open-ended hollow cylinder. The outer metal bellows 6, the inner metal bellows 7 and the partition wall 8 are substantially rotationally symmetrical about a respective longitudinal axis L and arranged concentrically with the body axis of the piezoelectric actuator 2. In the partition wall 8 is a throttle point 24 which connects the first sub-chamber 10 with the second sub-chamber 11.

The outer metal bellows 6, the inner metal bellows 7 and the dividing wall 8 are at least laterally spaced apart (with respect to the body axis of the piezoactuator 2 and the longitudinal axis L, respectively).

The outer metal bellows 6, the inner metal bellows 7 and the partition wall 8 are aligned so that their open end faces or end faces point in the direction of a cover 9 and an end plate, respectively. The outer metal bellows 6, the inner metal bellows 7 and the partition wall 8 are fastened with their open sides in particular directly or indirectly to the cover 9. More specifically, here is the inner metal bellows 7 hermetically and firmly attached to the lid 9 with its open side or with its free edge, z. B. by means of a welded connection. The outer metal bellows 6 is hermetically attached to a laterally projecting edge region of the free edge of the partition 8, for example by a welded connection. The outer metal bellows 6 and the partition wall 8 thus form a first partial chamber 10.

The partition wall 8 is also fastened with its free edge to the cover 9, namely laterally outside with respect to the inner metal bellows 7, e.g. by means of a welded joint. The inner metal bellows 7, the partition wall 8 and the cover 9 form a second sub-chamber 11. The gas-filled chamber 12 formed by an inner volume of the second metal bellows 7 is thus separated from the second sub-chamber 11 only by the second metal bellows 7. The gas-filled chamber 12 need not be hermetically sealed relative to an environment of the valve 1 and may be pneumatically open, for example, with the environment via one or more through-openings (o.Fig.).

The plunger 4 is thus articulated on an outer side of the lid 9, and a cover 9 of the opposite bottom portion 13 of the outer metal bellows 6 is connected to a further fixed bearing 14. The thermal compensator 5 and the piezoelectric actuator 2 are therefore connected mechanically in series and inserted between the two fixed bearings 3, 14.

The thermal compensator 5 has at its outer metal bellows 6 to a hydraulic connection 15, to which here a provided with a throttle 16 hydraulic line 17 is connected. The hydraulic line 17 leads to a further metal bellows 18 which encloses a further hydraulic chamber 18a filled with the hydraulic fluid H. The metal bellows 18 is rearwardly connected to a further fixed bearing 19 or lies on it. An open end of the metal bellows 18 is closed by an actuator in the form of a secondary plunger 20. The secondary plunger 20 is mounted linearly displaceable and is urged by means of a spring element 21 in the further metal bellows 18. The secondary plunger 20 is provided as an actuator for opening or closing a valve element 22 which can selectively open or close a fluid line 23, eg, a fuel supply line to a combustion chamber of an engine. The secondary plunger 20 may be integrated into the valve 22 or constitute a part of this valve 22.

The first sub-chamber 10, the second sub-chamber 11, the hydraulic line 17 and the further metal bellows 18 are filled with a substantially incompressible hydraulic fluid H. The hydraulic fluid H may be, for example, a hydraulic oil. The incompressibility can be supported for example by a vacuum filling.

The valve 1 between the lift actuator 2 and the secondary plunger 20 may also be referred to as a hydraulic lever.

In an operation of the valve 1 with a rapid lifting movement of the piezoelectric actuator 2, the plunger 4 is relatively quickly extended or moved in the direction of the cover 9. Since the piezoelectric actuator 2 is supported rearwardly by the fixed bearing, the cover 9 is displaced in the direction of the bellows 6, 7 and the partition 8. Since the bottom 13 of the outer metal bellows 6 is supported on the fixed bearing 14, the movement of the cover 9 compresses the outer metal bellows 6 in the longitudinal direction. Due to the comparatively fast movement of the lifting plunger 4 occurs during its actuation time only a small, practically insignificant amount of hydraulic fluid H through a throttle point 24th

Consequently, a pressure can build up in the first sub-chamber 10, which pressure is not forwarded to the second sub-chamber 11 and thus generated substantially loss-free. The increased pressure is transmitted via the hydraulic line 17 to the hydraulic fluid H located in the metal bellows 18, so that the primary plunger 20 is extended against the pressure of the spring element 21 and the valve 22 switch, for example open, can.

With the completion of the actuation of the piezoelectric actuator 2, the primary plunger 4 is moved back again by the spring force of the outer metal bellows 6 and the pressure in the hydraulic fluid H decreases again. As a result, the secondary plunger 20 is again in the metal bellows 18 by the spring element 21 shifted, so that a switching position of the valve 22 is reset again, the valve 22 is closed again, for example.

For rapid movements, as are typical when actuating a piezoactuator 2, the hydraulic temperature compensator 5 thus serves to build up pressure in the valve 1.

In the event that the valve 1 heats up slowly (in comparison to an actuation of the piezoactuator 2), the pressure of the hydraulic fluid H will increase slowly due to a temperature expansion. This increases a pressure difference between the second sub-chamber 11 and the gas-filled chamber 12, so that the gas-filled chamber 12 is compressed by a compression of the second metal bellows 7 along the longitudinal axis L and correspondingly increases the volume of the second sub-chamber 11. Due to the increase in volume of the second sub-chamber 11, the hydraulic fluid H relaxes again and can be maintained at a pressure that is only slightly increased with respect to the original temperature level. The gas-filled chamber 12 thus serves as a compensation volume for compensation of a temperature-related volume expansion of the hydraulic fluid H. Thus, a volume change produced due to slow processes, for example a temperature change, can be effectively limited. Since the throttle point 24 is practically permeable to the hydraulic fluid H during slow processes, the limitation of the pressure increase of the hydraulic fluid H will also be effective for the other filled with the hydraulic fluid H areas of the valve 1, namely for example for the first sub-chamber 10 and the metal bellows 18. This in turn allows a position, in particular rest position of the secondary plunger 20 are kept virtually independent of temperature fluctuations on the valve, whereby a switching accuracy is improved.

Fig.2 shows a sectional side view of a hydraulic temperature compensator 25 according to a second Embodiment which, for example, instead of the hydraulic temperature compensator 5 in the valve 1 can be installed. The hydraulic temperature compensator 25 has opposite the hydraulic temperature compensator 5 an additional compression spring 26 in the gas-filled chamber 12. The compression spring is designed here as a spiral spring which is supported on the one hand on the cover 9 and on the other hand on a bottom 27 of the inner metal bellows 7. By the compression spring 26, the inner metal bellows 7 is stretched more, and it is functionally stiffened against deformation in the longitudinal direction. Thus, the compression spring 26 causes the system pressure of the hydraulic fluid to increase. Further, by the compression spring 26, a relationship between a pressure change of the hydraulic fluid H and an associated increase in the volume of the second sub-chamber 11 can be set very precisely, and thus also a relationship between a pressure level of the hydraulic fluid H and a temperature of the hydraulic fluid H.

Figure 3 shows a sectional side view of a hydraulic temperature compensator 28, which is used for example in place of the hydraulic temperature compensator 5 in the valve 1. In contrast to the hydraulic temperature compensator 5, the hydraulic temperature compensator 28 has a flutter valve 29 on the dividing wall, which has an associated flap 30 on an outer side of the dividing wall 8 which borders on the first partial chamber 10. The flutter valve 29 causes a "dead time" between two actuations of the piezoelectric actuator 2 is reduced during normal operation. Because each time the piezoelectric actuator 2 presses the lid 9 down over the plunger 4, the pressure increases as described in the first sub-chamber 10. Although this is a respect to a single operation only negligible amount of hydraulic fluid H through the throttle point 24 of the first sub-chamber 10 is pressed into the second sub-chamber 11. When the plunger 4 returns to its rest position, this still results in a, albeit small, pressure difference between the first sub-chamber 10 and The second sub-chamber 11 in the direction of the first sub-chamber 10. This pressure difference is preferably reduce before the piezoelectric actuator 2 can be operated again, otherwise in the long term, the hydraulic fluid H is pumped into the second sub-chamber 11. The flutter valve 29 (or any other suitable unidirectional valve which has a comparatively large flow cross-section and allows the hydraulic fluid from the second sub-chamber 11 into the first Teilkammmer 10) accelerates this pressure compensation and allows a faster re-actuation of the piezoelectric actuator 2 and the plunger 4th

Of course, the present invention is not limited to the embodiments shown.

Thus, in the exemplary embodiments shown, the thermal temperature compensator 5, 25, 28 may be manufactured separately and installed and filled as a unit in the valve 1.

Alternatively, the hydraulic temperature compensator may be more integrated into the valve 1, for example, in that the outer metal bellows 6 and the metal bellows 18 are present as a single metal bellows and thus the actuator 20 would be separated from the second metal bellows 7 only by the hydraulic fluid H. As a result, the hydraulic line 17 could be omitted, and it is a valve with a particularly compact design achievable.

Also, features of the different embodiments may be combined, e.g. for a hydraulic temperature compensator with a compression spring in the gas-filled chamber and in addition a unidirectional valve in the partition wall.

Claims (13)

1. Hydraulic temperature compensator (5; 25; 28), at least comprising

   - a longitudinally extensible hydraulic chamber (10, 11) and

   - a gas-filled chamber (12) which is at least partly enclosed by the hydraulic chamber (10, 11),

   - wherein the hydraulic chamber (10, 11) is subdivided into a first sub-chamber (10) and a second sub-chamber (11) which are hydraulically connected to each other by means of at least one throttle point (24),

   - wherein the second sub-chamber (11) adjoins the gas-filled chamber (12),

   and wherein

   - the hydraulic chamber (10, 11) is formed by means of an inner wall (7) contactlessly inserted into an outer wall (6),

   - a partition (8) is contactlessly inserted between the outer wall (6) and the inner wall (7) in order to form the first sub-chamber (10) and the second sub-chamber (11) and the partition (8) includes the at least one throttle point (24),

   - the inner wall (7), the outer wall (6) and the partition (8) are each open at one side and are hermetically attached by their respective open side to a common cover (9), and

   - the gas-filled chamber (12) is formed by means of an inside surface of the inner wall (7).
2. Hydraulic temperature compensator according to claim 1, wherein the gas-filled chamber is an open gas-filled chamber.
3. Hydraulic temperature compensator (5; 25; 28) according to one of the preceding claims, wherein the inner wall (7) and the outer wall (6) are in each case embodied in the form of a bellows that is open at an end side.
4. Hydraulic temperature compensator (5; 25; 28) according to one of the preceding claims, wherein the partition (9) is embodied in the form of a hollow cylinder that is open at an end side.
5. Hydraulic temperature compensator (5; 25; 28) according to one of the preceding claims, wherein the outer wall (6) is hermetically attached to the partition (8) and the partition (8) is hermetically attached to the cover (9).
6. Hydraulic temperature compensator according to one of claims 1 to 4, wherein the outer wall and the partition are hermetically attached to the cover individually.
7. Hydraulic temperature compensator (25) according to one of the preceding claims, wherein at least one compression spring element is accommodated in the gas-filled chamber.
8. Hydraulic temperature compensator (28) according to one of the preceding claims, wherein the hydraulic chamber (10, 11) has a unidirectional valve (29), in particular a flutter valve, which enables a flow from the second sub-chamber (11) into the first sub-chamber (10).
9. Hydraulic temperature compensator according to one of the preceding claims, wherein the hydraulic chamber (10, 11) is filled with a substantially incompressible fluid, in particular with oil filled under vacuum.
10. Stroke transmitter (1), at least comprising

    - a hydraulic temperature compensator (5; 25; 28) according to one of the preceding claims, wherein the hydraulic temperature compensator (5; 25; 28) at least comprises

    - a longitudinally extensible hydraulic chamber (10, 11) and

    - a gas-filled chamber (12) which is at least partly enclosed by the hydraulic chamber (10, 11),

    - wherein the hydraulic chamber (10, 11) is subdivided into a first sub-chamber (10) and a second sub-chamber (11) which are hydraulically connected to each other by means of at least one throttle point (24),

    - wherein the second sub-chamber (11) adjoins the gas-filled chamber (12),

    and wherein the stroke transmitter (1) further comprises:

    - a stroke actuator (2) acting on the temperature compensator (5; 25; 28), and

    - a further hydraulic chamber (18a) which is fluidically connected to the first sub-chamber (10) of the hydraulic chamber (10, 11) of the temperature compensator (5; 25; 28), and

    - wherein the further hydraulic chamber (18a) is in fluidic connection with a displaceably mounted actuating element (20).
11. Stroke transmitter (1) according to claim 10, having a hydraulic temperature compensator (5; 25; 28) according to one of claims 1 to 9, wherein the stroke actuator (2) is connected to the cover (9).
12. Stroke transmitter (1) according to one of claims 10 or 11, wherein the stroke actuator (2) and the temperature compensator (5; 25; 28) are held between two thrust bearings (3, 14).
13. Stroke transmitter (1) according to one of claims 10 to 12, wherein the stroke transmitter (1) constitutes a part of an injector.

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