Transformer device for an x-ray device

Abstract

The present invention relates to a transformer device (10) for an X-ray device (100), having at least two partial transformers (20), each partial transformer (20) having a primary winding (22) and a secondary winding (24) and the at least two partial transformers (20) being electrically conductively connected to one another in series, such that in each case the secondary winding (24) of one partial transformer (20) is electrically conductively connected to the primary winding (22) of an adjacent partial transformer (20) in order to form a transformer cascade (30), the primary winding (22) of the first partial transformer (20) in the transformer cascade (30) furthermore having a low-voltage connection (12) and the secondary winding (24) of the last partial transformer (20) in the transformer cascade (30) furthermore having a high-voltage connection (14).

Description

[0001] Transformer device for an X-ray device

[0002] The present invention relates to a transformer device for an X-ray device, a manufacturing method for manufacturing such a transformer device, an X-ray device comprising such a transformer device, and a control method for controlling such an X-ray device.

[0003] It is known that X-ray devices for high-voltage operation require appropriate transformers to transform the voltage to the desired high-voltage level. Since very high voltages are typically required to ensure the operation of the X-ray source in an X-ray device, correspondingly complex transformer devices are necessary. Known solutions utilize transformer devices with epoxy encapsulation to safely electrically isolate the high potential differences between the input and output of such a single high-voltage transformer from surrounding components.

[0004] A disadvantage of the known solutions is that the high-voltage transformers for the X-ray devices are usually custom-made. When designing and sizing the X-ray source of an X-ray device, the high-voltage requirement is determined in these known solutions. Based on this requirement and the available standard low-voltage source, a high-voltage transformer is then developed that can provide the necessary potential difference between the low-voltage source and the high-voltage requirement of the X-ray source. This custom design involves considerable engineering effort, which is reflected in the correspondingly high costs for the high-voltage transformer device. Furthermore, these are special components that are correspondingly expensive to replace if the high-voltage transformer device in the X-ray device fails.In particular, such specialized high-voltage transformers cannot be manufactured and stocked as standard components. In the event of a defect, this leads to long downtimes of the X-ray device until the specialized component, in the form of the high-voltage transformer, is available again.

[0005] The object of the present invention is to at least partially overcome the disadvantages described above. In particular, it is the object of the present invention to provide a robust replacement for a high-voltage transformer in a cost-effective and simple manner.

[0006] The foregoing problem is solved by a transformer device with the features of claim 1, a manufacturing method with the features of claim 13, an X-ray device with the features of claim 14, and an inspection method with the features of claim 15. Further features and details of the invention will become apparent from the claims, the description, and the drawings. Features and details described in connection with the transformer device according to the invention naturally also apply in connection with the manufacturing method, the X-ray device, and the inspection method according to the invention, and vice versa, so that the disclosure of the individual aspects of the invention always makes, or can make, reciprocal references.

[0007] According to the invention, a transformer device is provided for an X-ray device. To provide the desired transformer functionality, the transformer device has at least two sub-transformers, each sub-transformer having a primary winding and a secondary winding. The at least two sub-transformers are electrically connected to each other in series, such that the secondary winding of one sub-transformer is electrically connected to the primary winding of an adjacent sub-transformer to form a transformer cascade. Furthermore, the primary winding of the first sub-transformer of the transformer cascade is configured with a low-voltage connection, and the secondary winding of the last sub-transformer of the transformer cascade is configured with a high-voltage connection.

[0008] The core concept of the invention is based on the principle of no longer designing a transformer device for an X-ray device as a single, specific high-voltage transformer. Instead, the desired transformer function is cascaded, thus distributing the potential differences among the individual sub-transformers. While the invention already offers advantages in providing at least two sub-transformers, the advantages explained later become even greater when a plurality of three, four, or even more sub-transformers are used to form the transformer cascade. Furthermore, it is irrelevant whether the sub-transformers are identical or different.

[0009] To form the transformer cascade, each sub-transformer is equipped with a primary and a secondary winding to provide its respective sub-transformer function. Due to its design, including the number of windings, conductor cross-sections, and similar factors, the combination of primary and secondary windings in each sub-transformer exhibits a transformer potential, meaning it can transform a voltage value at the primary winding to a higher voltage value at the secondary winding. Through cascading, i.e., connecting adjacent sub-transformers in series with electrical conductors, each sub-transformer can then progressively build up its sub-transformer function based on the output potential of the secondary winding of the preceding sub-transformer.From input to output via the transformer cascade, a potential difference is built up stepwise, so that a low-voltage source can now be connected to the low-voltage terminal of the first sub-transformer in the X-ray device in the usual way. Through the stepwise increase of the transformer functions and the potential differences, the desired high voltage for operating an X-ray source in the X-ray device is now available at the high-voltage terminal.

[0010] By replacing a single, specific high-voltage transformer with a plurality of sub-transformers, as in accordance with the invention, a multitude of advantages can be achieved. A first decisive advantage lies in the fact that the individual sub-transformers can be designed to be significantly simpler and less expensive than a dedicated high-voltage transformer. Since the potential differences associated with the individual sub-transformer functions are considerably smaller than in a high-voltage transformer, standard components can even be used. By using simpler and, in particular, standardized sub-transformers, a significant cost advantage can be achieved compared to previously known high-voltage transformers.

[0011] A further advantage is that, when the load is distributed across the individual transformer stages of the transformer cascade, the potential differences at each sub-transformer are significantly reduced compared to the high-voltage transformer. This translates in particular into a considerably smaller insulation requirement for each individual transformer cascade stage to ensure the desired electrical safety. Consequently, not only are the core components (the sub-transformers) significantly cheaper, but the secondary components, especially the necessary electrical insulation, can also result in further cost savings.While in known high-voltage transformers electrical insulation usually required encapsulation in a cast-in epoxy resin, in the transformer cascade according to the invention, significantly simpler and, above all, more cost-effective electrical insulations can be used in the transformer device.

[0012] Another advantage is that such a cascade system can be configured modularly. By simply increasing the number of sub-transformers, any desired adaptation to different transformer functions can be provided. For example, in a situation with low low voltage at the low-voltage source and high high-voltage requirements in the X-ray device, a correspondingly larger number of sub-transformers can be used. If a low-voltage source with a relatively high output voltage is already present and an X-ray source with lower high-voltage requirements is also planned, the same sub-transformers can still be used, but in smaller numbers.In this way, modular flexibility can be achieved in the design and construction of the transformer device without losing the advantages of the invention, particularly with regard to reduced complexity and reduced costs. It can be advantageous if, in a transformer device according to the invention, at least two sub-transformers, and in particular all sub-transformers of the transformer cascade, are arranged on a common printed circuit board, wherein the electrical connection between the adjacent sub-transformers is formed, in particular, by conductive sections on the common printed circuit board. Such a printed circuit board can also be referred to as a printed circuit board (PCB). Such printed circuit boards are also standard components and can be provided for the mounting of electronic and electrical components on them.For example, the positions of the sub-transformers to be mounted and soldered can be specified and defined during the manufacturing of such a printed circuit board. This makes it possible to form the individual electrical connections via the conductive sections directly on the common circuit board. By using standard components for the sub-transformers in conjunction with the common circuit board, further advantages can be achieved in terms of significant cost reduction and further reduction of complexity.Last but not least, this approach also makes it easier to vary the design. For example, depending on the actual application of the transformer device, different sub-transformers can be arranged on an identical circuit board for different X-ray devices, thus enabling different transformer functionalities to be implemented on the same circuit board while maintaining the same dimensions. It is particularly advantageous if all sub-transformers are arranged on the same side of the circuit board. Alternatively or additionally, however, it is also possible for the sub-transformers to be arranged on different sides of the circuit board, in order to achieve even further improved electrical isolation between the preferably cascaded and staggered sub-transformers. Other electronic components, such as a control module, can also be arranged on such a circuit board.For electrical contact with the conductive sections, plug connectors or solder pins, for example, can be provided. Similarly, for improved connectivity, the high-voltage connection and / or the low-voltage connection can be provided as plug connectors, and thus as plug-in connections, at the edges of the printed circuit board. In a transformer device according to the preceding paragraph, it can be advantageous if the at least two sub-transformers of the transformer cascade are arranged on the printed circuit board along a row axis, in particular laterally offset from the row axis. An arrangement along an axis, especially along a straight axis, leads to an elongated extension of the entire transformer device and thus to a further reduction of the required installation space.A lateral offset from such a series axis can ensure increased spacing between the individual sub-transformers, despite the elongated design. This increased spacing further improves the electrical insulation per stage in the transformer cascade. In particular, a varying offset is provided to enable the offset function to be implemented in a particularly space-efficient manner, despite the elongated length.

[0013] A further advantage arises when, in a transformer device according to the invention, the potential stages of the individual sub-transformers of the transformer cascade are identical or substantially identical. For the design of such a transformer device, the desired potential difference between the high-voltage and low-voltage connections is divided by the number of desired sub-transformers, resulting in the required potential difference per stage of the transformer cascade. Based on the required potential difference for each stage, a standard component of a sub-transformer is then selected and, according to the desired multiplier, often used as a plurality of sub-transformers to form the transformer cascade. This allows for a reduction to a single standard component of the sub-transformer, thereby optimizing cost reduction.

[0014] Further advantages can arise if, in a transformer device according to the invention, the partial transformers of the transformer cascade are structurally identical or substantially identical. Not only identical or substantially identical electrical configurations, but also identical or substantially identical electrical design can further enhance these advantages. This applies in particular to identical potential differences, as explained in the preceding paragraph. The design relates in particular to identical connections, identical construction, identical dimensions, and the like.

[0015] It is also advantageous if, in a transformer device according to the invention, at least one sub-transformer has a specific electrical potential difference that differs from the electrical potential difference of at least one other sub-transformer. This could, for example, be an arrangement in which different sub-transformers ensure different potential differences and thus also accommodate different loads. This makes it possible, for example, to allow larger potential differences on the low-voltage side than on the high-voltage side. For instance, it is conceivable to determine the required potential difference per stage of the transformer cascade as a function of the absolute potential value of that transformer stage.It is also possible that each transformer stage in the transformer cascade can bridge a potential difference with the same percentage. Finally, it is also conceivable to provide bypass connections to potentially supply different voltage values ​​at the high-voltage connection, depending on the operating mode of an X-ray source.

[0016] Furthermore, it is also advantageous if, in a transformer device according to the invention, at least one bypass connection is provided between two adjacent sub-transformers of the transformer cascade for an electrical bypass of at least one sub-transformer of the transformer cascade. For example, when providing four sub-transformers, such a bypass connection can be provided after the second sub-transformer, starting from the low-voltage connection. The voltage value, which has not yet been fully transformed, can then be tapped at this bypass connection and supplied to another electrical component. For example, the power supply for control modules or other structural electrical components of the X-ray device can be provided at such a bypass connection. This bypass connection is preferably switchable.Further advantages arise if, in a transformer device according to the invention, the individual transformers of the transformer cascade have at least partially identical or substantially identical transformation ratios with respect to the electrical potentials. Such identical transformation ratios can, for example, result in an increase of approximately 20% or 30% per stage of the transformer cascade. The greater the voltage increase across the transformer cascade from the low-voltage connection to the high-voltage connection, the greater the absolute potential differences per stage of the transformer cascade become with such a design. This configuration can ensure particularly simple and cost-effective electrical insulation.

[0017] It is also advantageous if, in a transformer device according to the invention, at least one of the sub-transformers, in particular the sub-transformer at the high-voltage connection, has a larger winding cross-section, at least of the secondary winding, compared to at least one other sub-transformer. The higher the expected current in a respective winding, the greater the advantages of increasing the winding cross-sections of the corresponding secondary winding. It is clearly evident here that this increased design effort with an increased winding cross-section can be limited to at least one or at least a subset of all sub-transformers.While high-voltage transformers traditionally required the entire secondary winding to be equipped with a correspondingly large conductor cross-section, this additional design effort can be limited here to just a few or even a single sub-transformer. This further reduces the cost and complexity of the transformer device.

[0018] It is also advantageous if, in a transformer device according to the invention with at least two sub-transformers, and in particular with all sub-transformers of the transformer cascade, a protective resistor is electrically connected to each. This is also arranged on a common circuit board and electrically connected to the respective sub-transformer by conductor sections. It allows voltage spikes to be mitigated and can be arranged on the same side of the circuit board as the sub-transformers.

[0019] Further advantages arise if, in a transformer device according to the invention, the sub-transformers have winding axes, wherein the winding axes of at least two sub-transformers, in particular all sub-transformers of the transformer cascade, are aligned parallel or substantially parallel to each other. This means that the individual sub-transformers can be arranged with their winding axes along, for example, a series axis, so that undesirable cross-influence of the magnetic fields of adjacent sub-transformers can be reduced or even eliminated. Alternatively, arc-shaped or curved arrangements of the individual sub-transformers relative to each other are also conceivable in principle.

[0020] A further advantage can be achieved if, in a transformer device according to the invention, at least one sub-transformer, and in particular all sub-transformers of the transformer cascade, have an insulating means for electrical isolation from at least one adjacent sub-transformer. While the reduction of potential differences per stage of the transformer cascade may, depending on the actual design, even eliminate the need for intermediate insulation altogether, providing such intermediate insulators as electrical insulating means can offer additional electrical safety. These intermediate insulators could, for example, be the partial housings surrounding the individual sub-transformers. However, reducing the intermediate insulation to individual insulating walls or sections is also conceivable.

[0021] Also part of the present invention is a manufacturing method for manufacturing a transformer device according to the invention, comprising the following steps:

[0022] - Arranging at least two partial transformers in a transformer cascade,

[0023] - Electrically conductive connection of the at least two partial transformers in series between a primary winding and a secondary winding of adjacent partial transformers. A manufacturing method according to the invention offers the same advantages as those explained in detail with reference to a transformer device according to the invention. In particular, the arrangement of an electrically conductive connection on a common printed circuit board is carried out, as has also already been explained with reference to the transformer device.

[0024] Furthermore, an object of the present invention is an X-ray device for generating X-rays, comprising a high-voltage X-ray source. The high-voltage X-ray source is electrically connected to the high-voltage terminal of a transformer device according to the invention and thus offers the same advantages as have been explained in detail with reference to a transformer device according to the invention.

[0025] Another object of the present invention is a control method for monitoring a high voltage on an X-ray device according to the invention, comprising the following steps:

[0026] - Determining a target high voltage,

[0027] - Determining a target low voltage based on the transformation ratio of the transformer device between the low-voltage terminal and the high-voltage terminal,

[0028] - Applying the specified target low voltage as the actual low voltage at the low-voltage connection of the transformer device.

[0029] A control method according to the invention also offers the same advantages as have been explained in detail with reference to a transformer device according to the invention.

[0030] Further advantages, features, and details of the invention will become apparent from the following description, in which exemplary embodiments of the invention are described in detail with reference to the drawings. The features mentioned in the claims and in the description can each be essential to the invention individually or in any combination. Figure 1 schematically shows an embodiment of a transformer device according to the invention.

[0031] Fig. 2 shows another embodiment of a transformer device according to the invention,

[0032] Fig. 3 shows another embodiment of a transformer device according to the invention,

[0033] Fig. 4 shows a further embodiment of a transformer device according to the invention,

[0034] Fig. 5 shows another embodiment of a transformer device according to the invention,

[0035] Fig. 6 shows another embodiment of a transformer device according to the invention,

[0036] Fig. 7 shows a further embodiment of a transformer device according to the invention and

[0037] Fig. 8 shows a schematic representation of an X-ray device according to the invention.

[0038] Figure 1 schematically shows the simplest embodiment of a transformer device 10 according to the invention. This forms the transformer cascade 30 with two partial transformers 20. The first partial transformer 20 is supplied with low voltage at the primary winding 22 via a low-voltage connection 12. Due to the design of the primary winding 22 and the secondary winding 24, a step-up from the low-voltage connection 12 to an intermediate voltage, not specified here, takes place. This intermediate voltage is then applied via the conductor sections 42 on the circuit board 40 to the primary winding 22 of the adjacent, here second, partial transformer 20.This second partial transformer 20 also has a transformer transformation ratio via the design between primary winding 22 and secondary winding 24, so that this intermediate voltage is now transformed up to the desired high voltage and the finished high voltage is made available at a high-voltage connection 14.

[0039] As shown in Figure 1, this transformer cascade 30 uses two sub-transformers 20, thus forming a two-stage transformer cascade 30. The individual sub-transformers 20 are arranged on a common circuit board 40. The electrically conductive connection is ensured by conductor sections 42 of the circuit board 40, resulting in a very compact and cost-effective design.

[0040] Figure 2 shows how a finer division into several stages of a transformer cascade 30 is possible in a simple and cost-effective manner. Here, five stages and correspondingly five sub-transformers 20 are provided. In this embodiment, all sub-transformers 20 are preferably electrically and structurally identical. This means that all exhibit the same correlation between the primary winding 22 and the secondary winding 24 for the same transformation ratios. The dimensions and connections are also preferably identical for all sub-transformers 20 of the embodiment shown in Figure 2.

[0041] The axially offset serial arrangement of the individual sub-transformers 20 follows a series axis RA. This axis can preferably coincide with the winding axis WA of the individual sub-transformers 20, which will be explained later, or be aligned parallel to it. In the embodiment of Figure 2, as a further development of the embodiment of Figure 1, either a higher potential difference between the low-voltage terminal 12 and the high-voltage terminal 14 can now be provided. Additionally or alternatively, the step size of the individual potential differences per stage of the transformer cascade 30, i.e., per sub-transformer 20, can be reduced compared to the embodiment of Figure 1.

[0042] Figure 3 shows a further development of the embodiment of Figure 2. Here, the second and the last partial transformer 20 are designed differently, which can be represented by the schematically different sizes of the primary winding 22 and the secondary winding 24. In reality, there could be, for example, a different number of windings or a different design for these partial transformers.

[0043] Transformers 20 mean.

[0044] Furthermore, in the embodiment shown in Figure 3, a bypass connection 32 is provided, which, starting from the low-voltage connection 12 after the second partial transformer 20, now enables a bypass of the remaining three partial transformers 20 to the high-voltage connection 14. Switching options for actively switching this bypass on and off are shown schematically.

[0045] Figure 4 also shows a further development of the embodiment of Figure 2. Here, the serial arrangement of all sub-transformers 20 is clearly visible again. However, the second sub-transformer 20 in each series is offset upwards from this serial axis RA in order to maintain the serial extent of the circuit board 40 by means of the corresponding offset, but to increase the actual and electrically insulating distance between the adjacent sub-transformers 20.

[0046] Figure 5 further illustrates a development which supplements the embodiment of Figure 2 with protective resistors 34. These are schematically provided here for the second to fourth stages of the transformer cascade 30.

[0047] Figure 6 clearly shows that a circular winding, particularly with a common winding axis WA for the primary winding 22 and secondary winding 24, is preferably provided for all partial transformers 20. In this embodiment of Figure 6, the three partial transformers 20 shown schematically are now equipped not only with parallel winding axes WA, but even with coaxial winding axes WA.

[0048] Figure 7 shows a real embodiment of a transformer device 10 according to the invention. In this embodiment, it is clearly visible that a lateral offset is again provided for the individual sub-transformers 20. This lateral offset also relates in particular to a parallel offset of the individual winding axes WA to the series axis RA. The use of insulating materials 26 for electrical isolation between the individual sub-transformers 20 is also evident in this embodiment. For the sake of clarity, the electrical wiring is not shown in Figure 7.

[0049] Figure 8 schematically shows an X-ray device 100 with a high-voltage X-ray source 110. A target high voltage HUS is required to operate the high-voltage X-ray source 110. This target high voltage can be provided by a transformer device 10, for example, according to one of the embodiments shown in Figures 1 to 7. If a control module detects that the X-ray source 110 is to be operated with a target high voltage HUS, the required target low voltage LUS can then be determined in the transformer device 10 using the overall transformation ratios of the transformer cascade 30. A current low voltage LUI is then applied to the low-voltage connection 12 according to the determined target low voltage LUS. This current low voltage provides the desired target high voltage HUS via the high-voltage connection 14 of the high-voltage X-ray source 110.

[0050] The preceding explanation of the embodiments describes the present invention exclusively by way of examples, and of course all features of the present invention can be freely combined with one another.

[0051] Reference symbol list

[0052] 10 Transformer device

[0053] 12 Low-voltage connection

[0054] 14 High-voltage connection

[0055] 20-part transformer

[0056] 22 Primary winding

[0057] 24 Secondary winding

[0058] 26 Insulation materials

[0059] 30 transformer cascade

[0060] 32 Bypass connection

[0061] 34 Protective resistance

[0062] 40 printed circuit boards

[0063] 42 Main Section

[0064] 100 X-ray devices

[0065] 110 High-voltage X-ray source

[0066] RA series axle

[0067] WA winding axis

[0068] HUS target high voltage

[0069] LUS target low voltage

[0070] LUI Ist-Low Voltage

Claims

Patent claims 1. Transformer device (10) for an X-ray device (100), comprising at least two partial transformers (20), wherein each partial transformer (20) has a primary winding (22) and a secondary winding (24) and the at least two partial transformers (20) are electrically connected in series to each other, such that the secondary winding (24) of one partial transformer (20) is electrically connected to the primary winding (22) of an adjacent partial transformer (20) to form a transformer cascade (30), wherein the primary winding (22) of the first partial transformer (20) of the transformer cascade (30) has a low-voltage connection (12) and the secondary winding (24) of the last partial transformer (20) of the transformer cascade (30) has a high-voltage connection (14).

2. Transformer device (10) according to claim 1, characterized in that at least two partial transformers (20), in particular all partial transformers (20) of the transformer cascade (30), are arranged on a common circuit board (40), wherein the electrical connection between the adjacent partial transformers (20) is formed in particular by conductor sections (42) on the common circuit board (40).

3. Transformer device (10) according to claim 2, characterized in that the at least two partial transformers (20) of the transformer cascade (30) are arranged on the circuit board (40) along a row axis (RA), in particular laterally offset to the row axis (RA).

4. Transformer device (10) according to one of the preceding claims, characterized in that the potential stages of the individual partial transformers (20) of the transformer cascade (30) are identical or substantially identical.

5. Transformer device (10) according to one of the preceding claims, characterized in that the partial transformers (20) of the transformer cascade (30) are structurally identical or substantially identical.

6. Transformer device (10) according to one of the preceding claims, characterized in that at least one partial transformer (20) has a specific electrical potential difference which differs from the electrical potential difference of at least one other partial transformer (20).

7. Transformer device (10) according to one of the preceding claims, characterized in that at least one bypass connection (32) is formed between two adjacent partial transformers (20) of the transformer cascade (30) for an electrical bypass of at least one partial transformer (20) of the transformer cascade (30).

8. Transformer device (10) according to one of the preceding claims, characterized in that the partial transformers (20) of the transformer cascade (30) have at least partially identical or substantially identical transformation ratios with respect to the electrical potentials.

9. Transformer device (10) according to one of the preceding claims, characterized in that at least one of the partial transformers (20), in particular the partial transformer (20) at the high-voltage connection (14), has an increased winding cross-section of at least the secondary winding (24) compared to at least one other partial transformer (20).

10. Transformer device (10) according to one of the preceding claims, characterized in that a protective resistor (34) is electrically connected to at least two partial transformers (20), in particular to all partial transformers (20) of the transformer cascade (30).

11. Transformer device (10) according to one of the preceding claims, characterized in that the partial transformers (20) have winding axes (WA), wherein the winding axes (WA) of at least two partial transformers (20), in particular all partial transformers (20) of the transformer cascade (30), are aligned parallel or substantially parallel to each other.

12. Transformer device (10) according to one of the preceding claims, characterized in that at least one partial transformer (20), in particular all partial transformers (20) of the transformer cascade (30), have an insulating means (26) for electrical insulation to at least one adjacent partial transformer (20).

13. Manufacturing method for manufacturing a transformer device (10) with the features of any one of claims 1 to 12, comprising the following steps: - Arranging at least two partial transformers (20) in a transformer cascade (30), - Electrically conductive connection of at least two partial transformers (20) in series between a primary winding (22) and a secondary winding (24) of adjacent partial transformers (20).

14. X-ray device (100) for generating X-rays, comprising a high-voltage X-ray source (110), wherein the high-voltage X-ray source (110) is electrically connected to the high-voltage connection (14) of a transformer device (10) having the features of one of claims 1 to 12.

5. Control method for monitoring a high voltage on an X-ray device (100) with the features of claim 14, comprising the following steps: - Determining a target high voltage (HUS), - Determining a target low voltage (LUS) based on the transformation ratio of the transformer device (10) between the low voltage terminal (12) and the high voltage terminal (14), - Applying the specified target low voltage (LUS) as actual low voltage (LUI) at the low voltage connection (12) of the transformer device (10).

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