JPH04328298A - X-ray generator - Google Patents

Abstract

PURPOSE:To provide an X-ray device for a round of visits which is of a comparatively small size and of little probility of failure. CONSTITUTION:In an inverter type X-ray generator, a battery 14, a DC voltage conversion circuit 26 to convert a battery current into a DC current whose voltage is higher and a capacitor 18 to be changed by an output of the voltage conversion circuit 26 are installed. The current discharged from the capacitor 18 is used for an input to an inverter circuit 19. The voltage of the inverter 19 is boosted by a transformer 20 for application to an X-ray tube 23.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an X-ray apparatus for making rounds, which is mainly used while moving within a hospital, and more particularly to a high voltage generator thereof.

0002

2. Description of the Related Art In recent years, X-ray equipment for medical rounds has been shifting from the conventional capacitor type to an inverter type that can generate a stable high voltage. Among these, cordless inverter-type X-ray apparatuses for medical rounds equipped with a battery are currently becoming the mainstream of X-ray apparatuses for medical rounds because they can be used even in rooms without electrical outlets.

The structure and operation of a conventional cordless inverter type X-ray apparatus for medical rounds will be explained with reference to FIG. Before moving and using this device, first, plug the plug 31 into an outlet in a room with a power source and charge the battery 34. Here, as will be described later, the battery 34 is composed of many unit cells connected in series, and its voltage is higher than the 100V of the commercial power supply. Therefore, the AC voltage from the plug 31 in the battery charging circuit 41 is automatically The voltage is boosted by the transformer 32. The boosted AC current is rectified into DC current by the rectifier circuit 33, and the battery 34 is charged.

When using this X-ray device for medical rounds, the DC current supplied from the battery 34 is connected to the inverter circuit 3.
5 converts it into an AC current and inputs it to the high voltage generation transformer 36. 40~ generated by the high voltage generation transformer 36
A high voltage of about 125 kV is rectified by a rectifier circuit 37,
is applied to the X-ray tube 39. During this time, the applied voltage is detected by the tube voltage detection circuit 38, fed back to the control circuit 40, and used to control the inverter 35.

[0005]

SUMMARY OF THE INVENTION The conventional X-ray apparatus described above has a problem in that it is not possible to increase the power P applied to the X-ray tube 39. This is for the following reasons. Considering the primary side of the high voltage generation transformer 36, the electric power P
is the product of voltage and current, so in order to increase the power P, it is necessary to increase the primary voltage or primary current. The conventional device uses a battery 34 as a primary power source, but due to its characteristics, the battery has a limit on the current that can flow through itself. Therefore, the only way to obtain high power is to increase the battery voltage. However, the voltage of easily available standard battery cells is 12
V, it is necessary to connect several dozen such battery cells in series in order to obtain the power necessary for an X-ray device for medical rounds. Such an X-ray device for medical rounds has a large volume due to the battery alone, and weighs several hundred kilograms, making it extremely difficult to handle and has poor operability. Furthermore, since a large number of battery cells are connected in series and used, the probability of failure increases and there are maintenance problems. The present invention has been made to solve these problems, and its purpose is to provide an X-ray apparatus for medical rounds that is relatively compact and has a low probability of failure.

[0006]

[Means for Solving the Problems] In the present invention, which has been made to solve the above problems, in an inverter type X-ray generator, (a) a battery and (b) a DC current supplied from the battery is increased. (c) a capacitor charged by the current output from the DC voltage conversion circuit, and the current discharged from the capacitor (c) is input to the inverter circuit. It is characterized by:

[0007]

[Operation] In the inverter type X-ray generator, the output of the inverter circuit is boosted by a transformer to generate high voltage to be applied to the X-ray tube. In the present invention, the discharge current of the capacitor (c) is used as the input of the inverter circuit, and the battery (a)
Do not directly use the output current from the Therefore, the battery (
There is no need to increase the voltage in a), and a small number of batteries can be used.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure and operation of a cordless inverter type X-ray apparatus for medical rounds, which is an embodiment of the present invention, will be explained with reference to FIG. Before actually using this device, first insert the plug 11 into the outlet in a room with a power source, and then plug the battery 14 into the outlet.
to charge. The circuit 25 for charging the battery includes:
In addition to the plug 11, a step-down transformer 12 and a rectifier circuit 13 are included. Unlike the conventional device shown in FIG. 1, in this embodiment, the battery 14 uses only two standard 12V battery cells, so the transformer 12 of the battery charging circuit 25 is designed to step down the trademarked 100V power supply. It has become.

[0009] After charging of the battery 14 is completed, the present X-ray apparatus is ready for use. During use, the inverter 15 converts the DC current supplied from the battery 14 into AC current, and the insulation transformer 16 converts the DC current into an AC current of about several hundred volts (for example, 6 volts).
00V) to a medium voltage. The AC current boosted to the intermediate voltage is converted into DC current by the rectifier circuit 17, and the capacitor 18 is charged with this. When the charging of the capacitor 18 is completed, X-ray irradiation becomes possible, and the control circuit 24 operates the inverter 19 when the operator operates a switch (not shown). The inverter 19 converts the DC current discharged from the capacitor 18 into AC current, and the high voltage transformer 20 converts the tube voltage (e.g. 65kV) into AC current.
). The AC current that has become the tube voltage is converted back into DC current by the rectifier circuit 21 and applied to the X-ray tube 23. Similar to conventional X-ray equipment, the tube voltage is monitored by tube voltage detection circuit 22 and fed back to control circuit 24. The control circuit 24 controls the inverter 15 of the capacitor charging circuit 26 and the inverter 19 of the high voltage circuit, and the high voltage inverter 19 controls X based on the monitored tube voltage.
The voltage applied to the wire tube 23 is controlled to a constant value.

Capacitor 1 of the X-ray device for medical rounds according to this embodiment
FIG. 2 shows changes in the charging voltage of X-ray tube 8 and the tube voltage of X-ray tube 23 during exposure. As shown in FIG. 2, since the X-ray apparatus of this embodiment is essentially an inverter type, the tube voltage is kept almost constant during exposure. On the other hand, in this embodiment, since the battery does not require such a high voltage, the volume and weight of the battery can be made very small. Therefore,
The X-ray machine is easy to move and handle during medical rounds. In addition, since the capacitor 18 only needs to store the energy required for one exposure, its energy capacity is smaller than when many batteries are connected in series, and the volume and weight of the capacitor 18 are smaller than that of conventional rounds. The volume and weight of the X-ray device battery will be smaller than that of the battery. Note that various types of DC/DC booster circuits can be used as the capacitor charging circuit 26 in addition to the example shown in FIG. can do.

[0011]

[Effects of the Invention] Since the X-ray generator according to the present invention does not directly convert the battery voltage into a high voltage, the battery does not require a very high voltage. Therefore, only a small number of battery cells are required, and the volume and weight can be made very small. As a result, the X-ray generating device according to the present invention can be used as an X-ray device for making rounds that is particularly suitable for making rounds in a hospital and is easy to move and easy to handle. In addition, since an inverter is used in the high pressure generation section,
It can supply high output and stable tube voltage. Furthermore, because the number of battery cells is significantly reduced, the probability of failure due to battery malfunction is significantly reduced, resulting in a highly reliable X-ray generator.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of a cordless inverter-type X-ray device for medical rounds, which is an embodiment of the present invention.

FIG. 2 is a graph showing changes in the charging voltage of the capacitor and the tube voltage of the X-ray tube during exposure by the X-ray apparatus of the example.

FIG. 3 is a circuit diagram of a conventional cordless inverter-type X-ray device for medical rounds.

[Explanation of symbols]

11, 31...Plug
12, 32...Battery charging transformer 13, 33...Battery charging rectifier circuit 14, 34...
Battery 15... Inverter for charging capacitor 16... Transformer for charging capacitor 17... Rectifier circuit for charging capacitor 18... Capacitor 19, 35... Inverter
20, 36...High voltage generation transformer 21, 37...High voltage rectifier circuit 2
2, 38...Tube voltage detection circuit 23, 39...X-ray tube

Claims (1)

[Claims] Claim 1: In an inverter type X-ray generator,
A battery, a DC voltage conversion circuit that converts DC current supplied from the battery into a DC current having a higher voltage, and a capacitor that is charged by the current output from the DC voltage conversion circuit, and the capacitor is discharged. X, characterized in that the current that is generated is input to the inverter circuit.
Line generator.