JP5477236B2 - X-ray equipment - Google Patents

Description

  The present invention relates to an X-ray tube that irradiates a subject with X-rays, an X-ray detector such as a flat panel detector that detects X-rays emitted from the X-ray tube and passed through the subject, and an X-ray The present invention relates to an X-ray imaging apparatus including a collimator mechanism that is disposed between a tube and a subject and adjusts an X-ray irradiation field irradiated from the X-ray tube toward the subject.

  In such an X-ray imaging apparatus, when adjusting the X-ray field irradiated from the X-ray tube toward the subject patient using the collimator mechanism, the collimator mechanism is arranged on the side opposite to the patient. A light irradiation field is formed by turning on the illumination field lamp provided, and the X-ray irradiation field adjusted by the collimator mechanism is visually recognized by this light irradiation field.

  In such a conventional X-ray imaging apparatus, when the lighting switch of the illumination field lamp is pressed, the illumination field lamp is lit only for a certain time. Further, Patent Document 1 discloses an X-ray imaging apparatus that detects the completion of the illumination field adjustment operation and turns off the illumination field lamp after a certain period of time.

JP 2007-15733 A

  If the illumination field lamp is turned on for a long time, the temperature of the apparatus rises due to heat generated from the illumination field lamp, and there is a risk of burns or the like to the operator or patient. For this reason, when the lighting time exceeds a certain level, or when it is detected that the temperature of the device has exceeded a certain level by a thermostat or the like, the safety device is activated and lighting of the illumination field lamp is prohibited. Yes. In the case of adopting such a configuration, when X-ray imaging is continued thereafter, it is necessary to resume imaging at the timing when the temperature of the apparatus becomes below a certain level. At this time, it is difficult to determine whether or not the temperature of the apparatus has become below a certain level. Although it is possible to attach a thermometer to the apparatus and measure the temperature of the apparatus, there is a problem that the manufacturing cost of the apparatus increases.

  The present invention has been made to solve the above-described problems, and can prevent the temperature of the apparatus from exceeding a certain level without increasing the manufacturing cost of the apparatus, and the temperature of the apparatus can be equal to or less than a certain level. An object of the present invention is to provide an X-ray imaging apparatus capable of resuming X-ray imaging when it becomes.

  The invention according to claim 1 is an X-ray tube that irradiates a subject with X-rays, an X-ray detection unit that detects X-rays emitted from the X-ray tube and passed through the subject, and the X-rays A collimator mechanism that is disposed between the X-ray tube and the subject and adjusts an X-ray irradiation field irradiated from the X-ray tube toward the subject; and an X-ray irradiation field adjusted by the collimator mechanism In an X-ray imaging apparatus provided with an irradiation field lamp for enabling visual recognition, a relationship between a lighting time of the irradiation field lamp and a temperature increase, and a relationship between a lighting time of the illumination field lamp and a temperature decrease A storage means for storing temperature rise and fall data indicating, a pseudo temperature counter for calculating the current illumination lamp temperature from the lighting time and extinguishing time of the irradiation field lamp and the temperature rise and fall data, and the pseudo temperature counter Calculated lighting The lighting of the illumination field lamp is prohibited when the temperature of the field lamp exceeds a set temperature, and the illumination of the illumination field lamp is turned on when the temperature of the illumination field lamp calculated by the pseudo temperature counter is equal to or lower than the set temperature. And a lighting control unit that permits the above.

  According to the first aspect of the present invention, lighting of the illumination field lamp is prohibited when the temperature of the illumination field lamp calculated by the pseudo temperature counter exceeds the set temperature, and the illumination field lamp calculated by the pseudo temperature counter The temperature of the device can be prevented from becoming higher than a certain level by the action of the lighting control unit that permits the lighting of the illumination field lamp when the temperature is lower than the set temperature, and the temperature of the device is below a certain level. Then, X-ray imaging can be resumed. At this time, since the pseudo temperature counter is used, it is possible to prevent an increase in the manufacturing cost of the device as compared with the case where a temperature sensor is installed in the device.

1 is a schematic diagram of an X-ray imaging apparatus according to the present invention. It is a schematic diagram which shows principal parts, such as the X-ray irradiation part 3, etc. in the X-ray imaging apparatus which concerns on this invention. It is a block diagram which shows the main electric structures for implementing this invention in the control part. 3 is a graph showing temperature rise / fall data stored in a storage unit 44. It is a graph which shows the temperature (pseudo temperature) of the present illumination field lamp 24 calculated by the pseudo temperature counter 45. FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic diagram of an X-ray imaging apparatus according to the present invention.

  The X-ray imaging apparatus includes a table 2 on which a patient 1 as a subject is placed, an X-ray irradiation unit 3 including an X-ray tube 7 that emits X-rays toward the patient 1, and an X-ray detection unit. Flat panel detector 4 and a collimator mechanism including a plurality of movable diaphragms 6. X-rays irradiated from the X-ray tube 7 pass through the patient 1 and enter the flat panel detector 4. The flat panel detector 4 outputs an image signal corresponding to the incident X-ray.

  The collimator mechanism includes four movable diaphragms 6 for forming a rectangular region. When X-ray imaging is performed, an X-ray exposure range is set by moving the movable diaphragm 6 by driving a driving motor (not shown) in a state where an illumination field lamp 24 described later is turned on. In this state, by irradiating X-rays from the X-ray tube 7, X-rays are irradiated only to the exposure range defined by the four movable diaphragms 6.

  FIG. 2 is a schematic diagram showing the main parts of the X-ray irradiation unit 3 and the like in the X-ray imaging apparatus according to the present invention.

  The X-ray irradiation unit 3 includes an additional filter moving mechanism including a rotating plate 11 in which a plurality of types of additional filters are disposed, and a motor 12 that rotates the rotating plate 11. The X-ray irradiation unit 3 is disposed on the side opposite to the patient 1 with respect to the collimator mechanism, and forms a light irradiation field for visually recognizing the X-ray irradiation field adjusted by the collimator mechanism. An illumination field lamp 24 and a mirror 25 are provided as means. The light irradiated from the illumination field lamp 24 is reflected by the mirror 25 and is irradiated to the patient 1 after the irradiation area is limited by the plurality of movable diaphragms 6 in the collimator mechanism. At this time, the X-rays transmitted from the X-ray tube 7 through the mirror 25 to the patient 1 and the light reflected from the illumination field lamp 24 by the mirror 25 and applied to the patient 1 have the same optical axis. And the focus is consistent. For this reason, the X-ray irradiation field and the light irradiation field formed by the collimator mechanism coincide.

  The motor 12 that rotates the rotating plate 11 and the illumination field lamp 24 are connected to the control unit 41 and controlled by the control unit 41. That is, the control unit 41 controls the motor 12 that rotates the rotating plate 11 to rotate the rotating plate 11. The control unit 41 controls the lighting state of the illumination field lamp 24. The control unit 41 is connected to an operation unit 42 for an operator to input various types of information and a display unit 43 for displaying various types of information.

  FIG. 3 is a block diagram showing a main electrical configuration for carrying out the present invention in the control unit 41.

  The control unit 41 includes a storage unit 44 for storing temperature rise / fall data indicating the relationship between the lighting time of the irradiation field lamp 24 and the temperature rise, and the relationship between the turn-off time of the illumination field lamp 24 and the temperature drop, and an irradiation field. A pseudo temperature counter 45 for calculating the current temperature of the illumination field lamp 24 from the lighting time and extinguishing time of the lamp 24 and the temperature rise / fall data stored in the storage unit 44, and the illumination field lamp 24 calculated by the pseudo temperature counter 45. When the temperature exceeds the set temperature, the lighting of the illumination field lamp 24 is prohibited, and the illumination of the illumination field lamp 24 is permitted when the temperature of the illumination field lamp 24 calculated by the pseudo temperature counter 45 falls below the set temperature. And a lighting control unit 46.

  FIG. 4 is a graph showing temperature increase / decrease data stored in the storage unit 44.

  The relationship between the lighting time of the irradiation field lamp 24 and the temperature rise shown by the solid line in FIG. 4 is that the illumination field lamp 24 is lit for a certain period of time and the temperature of the illumination field lamp 24 at that time is actually measured with a thermometer. Desired. Further, the relationship between the turn-off time of the illumination field lamp 24 and the temperature drop indicated by the broken line in FIG. 4 is that the illumination field lamp 24 that has risen to a certain temperature is turned off, and the temperature of the illumination field lamp 24 at that time is It is calculated | required by measuring to. The temperature increase / decrease data indicating the relationship between the lighting time of the irradiation field lamp 24 and the temperature rise and the relationship between the turn-off time of the illumination field lamp 24 and the temperature drop stored in the storage unit 44 are stored in the storage unit 44. Is done.

  When X-ray imaging is performed by the X-ray imaging apparatus having the above-described configuration, when the illumination field lamp 24 is turned on to check the X-ray irradiation field using the light irradiation field, the irradiation field lamp 24 is turned on. Temperature rises. The pseudo temperature counter 45 calculates the current temperature of the illumination field lamp 24 from the lighting time and extinguishing time of the irradiation field lamp 24 at this time and the temperature rise / fall data stored in the storage unit 44.

  FIG. 5 is a graph showing the current temperature (pseudo temperature) of the illumination field lamp 24 calculated by the pseudo temperature counter 45.

  The pseudo temperature counter 45 uses the temperature increase / decrease data stored in the storage unit 44 and calculates the current temperature of the illumination field lamp 24 based on the lighting time and extinguishing time of the irradiation field lamp 24. That is, when the illumination field lamp 24 is lit, the pseudo temperature is raised using the relationship between the lighting time of the irradiation field lamp 24 and the temperature rise shown by the solid line in FIG. On the other hand, when the illumination field lamp 24 is turned off, the pseudo temperature is lowered by utilizing the relationship between the lighting time of the irradiation field lamp 24 and the temperature drop shown by the broken line in FIG. Thereby, as shown by the solid line in FIG. 5, the temperature change of the illumination field lamp 24 is always observed as a pseudo temperature.

  When the illumination field lamp 24 is lit continuously and the pseudo temperature of the illumination field lamp 24 calculated by the pseudo temperature counter 45 exceeds the first set temperature T1, the lighting control unit 46 prohibits the illumination field lamp from being lit. . The pseudo temperature counter 45 constantly calculates and monitors the temperature drop of the illumination field lamp 24 due to the illumination field lamp 24 being extinguished. The lighting control unit 46 permits the lighting of the illumination field lamp when the temperature of the illumination field lamp 24 calculated by the pseudo temperature counter 45 becomes equal to or lower than the second set temperature T2. As a result, the illumination field lamp 24 can be turned on again to check the X-ray irradiation field. Note that the prohibition and permission states of the illumination field lamp 24 are displayed on the display unit 43, and the operator can always check them.

  As described above, in the X-ray imaging apparatus according to the present invention, it is possible to prevent the temperature of the apparatus from exceeding a certain level due to the lighting of the illumination field lamp 24, and the temperature of the apparatus has become a certain level or less. Sometimes X-ray imaging can be resumed quickly. In addition, since it is not necessary to install a thermometer for measuring the temperature of the illumination field lamp 24, it is possible to prevent an increase in the manufacturing cost of the apparatus.

  In the above-described embodiment, the second set temperature T2 for permitting lighting of the illumination field lamp 24 is set to a temperature lower than the first set temperature T1 for prohibiting illumination of the illumination field lamp 24. doing. However, the first set temperature T1 for prohibiting lighting of the illumination field lamp 24 and the second set temperature T2 for permitting lighting of the illumination field lamp 24 do not necessarily have to be different temperatures. These may be set as the same temperature. However, when these set temperatures are set to the same temperature, if the illumination field lamp 24 is turned on again immediately after the illumination field lamp 24 is turned off and the temperature of the illumination field lamp 24 is lowered, the short time is shortened. The lighting of the illumination field lamp 24 is prohibited again with time. Therefore, in such a case, it is preferable to take measures such as setting a certain time lag between the time when the illumination field lamp 24 is turned on and the time when it is permitted.

  In the above-described embodiment, the lighting of the illumination field lamp 24 is prohibited when the temperature of the illumination field lamp 24 calculated by the pseudo temperature counter 45 exceeds the first set temperature T1. Thus, when the temperature of the illumination field lamp 24 calculated by the pseudo temperature counter 45 approaches the first set temperature T1, the continuous lighting possible time of the illumination field lamp 24 may be shortened. In other words, when the illumination field lamp 24 is turned on, when the illumination field lamp is set to be extinguished by continuous lighting for 30 seconds, the temperature of the illumination field lamp 24 calculated by the pseudo temperature counter 45 is the first temperature. As the temperature approaches the preset temperature T1, the continuous lighting time may be shortened to about 25 seconds or 20 seconds, so that the temperature of the illumination field lamp 24 increases gradually.

DESCRIPTION OF SYMBOLS 1 Patient 2 Table 3 X-ray irradiation part 4 Flat panel detector 6 Movable diaphragm 7 X-ray tube 11 Rotating plate 12 Motor 24 Illumination field lamp 25 Mirror 41 Control part 42 Operation part 43 Display part 44 Memory | storage part 45 Pseudo temperature counter 46 Lighting control Part

Claims (1)

An X-ray tube that irradiates the subject with X-rays;
An X-ray detector that detects X-rays irradiated from the X-ray tube and passed through the subject;
A collimator mechanism that is disposed between the X-ray tube and the subject and adjusts an X-ray irradiation field irradiated from the X-ray tube toward the subject;
An irradiation field lamp for making the X-ray irradiation field adjusted by the collimator mechanism visible;
In an X-ray imaging apparatus comprising:
Storage means for storing temperature rise / fall data indicating the relationship between the lighting time of the irradiation field lamp and the temperature rise, and the relationship between the turn-off time of the illumination field lamp and the temperature drop;
From the lighting time and extinguishing time of the irradiation field lamp and the temperature rise and fall data, a pseudo temperature counter that calculates the temperature of the current illumination field lamp,
When the temperature of the illumination field lamp calculated by the pseudo temperature counter exceeds a set temperature, the lighting of the illumination field lamp is prohibited, and the temperature of the illumination field lamp calculated by the pseudo temperature counter becomes equal to or lower than the set temperature. A lighting control unit that allows the lighting of the illumination field lamp sometimes,
An X-ray imaging apparatus comprising:

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