CN210249857U - Digital X-ray photographic equipment - Google Patents

Abstract

The application provides a digital X-ray photography device, which comprises an X-ray emitter, a detector, a moving part for driving the X-ray emitter and/or the detector to move, a direct current motor with a power output end coupled to the moving part, a direct current motor driving circuit and a controller. The direct current motor driving circuit comprises a double-pole double-throw switch, two movable ends of the double-pole double-throw switch are respectively connected with a high potential point and a grounding point, and a first stage and a second stage of two groups of fixed ends are respectively connected with a positive pole and a negative pole of the direct current motor. The controller is used for controlling the two movable ends of the double-pole double-throw switch to be switched between the first pole and the second pole of the two groups of fixed ends respectively so as to enable current to flow through the direct current motor in different directions. The application provides a digital X-ray photography equipment, the direct current motor drive circuit that adopts drives direct current motor forward or reverse rotation, and power device is few, low cost, and the circuit is realized and software control is simple and convenient.

Description

Digital X-ray photographic equipment

Technical Field

The present application relates to the field of medical instruments, in particular to a digital radiography apparatus.

Background

In digital X-ray photography equipment, machine parts need to move in different dimensions, and are generally driven by a direct current motor, and the machine parts are controlled to move in different dimensions through the forward and reverse rotation of the direct current motor.

The circuit scheme of the direct current motor drive generally adopts an H-bridge structure, namely four vertical legs of an H are formed by four switches, and the direct current motor is a cross bar in the H. In order to make the motor run, a pair of switches on the diagonal line are required to be conducted, and the forward and reverse rotation of the motor is controlled through different current directions.

The H-bridge circuit structure in the digital X-ray photographing equipment has more power devices and higher cost, and the circuit realization, software control and the like have certain difficulty, thereby causing inconvenience to the movement of each part of the digital X-ray photographing equipment.

Disclosure of Invention

The application provides a digital X-ray photography equipment, can solve the power device that the H bridge circuit structure among the traditional digital X-ray photography equipment brought more, the cost is higher, and the circuit realizes and the big problem of software control degree of difficulty moreover.

The present application provides a digital radiography apparatus comprising: an X-ray emitter for generating X-rays; the detector is used for receiving the X-rays penetrating through the human body and converting the X-rays into electric signals; the moving component is used for driving the X-ray emitter and/or the detector to move; the power output end of the direct current motor is coupled to the moving part and used for driving the moving part to move; the input end of the direct current motor driving circuit is connected with direct current voltage, and the output end of the direct current motor driving circuit is electrically connected with the direct current motor and used for driving the direct current motor to rotate; the direct current motor driving circuit comprises a double-pole double-throw switch, two moving ends of the double-pole double-throw switch are respectively connected with a high-potential point and a grounding point, the first stage of the first group of immobile ends of the double-pole double-throw switch is connected with the positive pole of the direct current motor, and the second pole of the first group of immobile ends is connected with the negative pole of the direct current motor; the first pole of the second group of immobile ends of the double-pole double-throw switch is connected with the negative pole of the direct current motor, and the second pole of the second group of immobile ends is connected with the positive pole of the direct current motor; and the controller is used for controlling the two movable ends of the double-pole double-throw switch to be switched between the first pole and the second pole of the two groups of fixed ends respectively so as to enable the current to flow through the direct current motor in different directions.

The application provides a digital X-ray photography equipment, the direct current motor drive circuit that adopts drives direct current motor forward or reverse rotation, and power device is few, low cost, and the circuit is realized and software control is simple and convenient.

Drawings

FIG. 1 is a schematic view of an embodiment of a digital radiography apparatus;

FIG. 2 is a schematic diagram of one embodiment of a DC motor drive circuit;

FIG. 3 is a schematic diagram of an embodiment of a DC motor driving circuit;

FIG. 4 is a schematic diagram of another operating state of an embodiment of a DC motor driver circuit;

FIG. 5 is a schematic diagram of an embodiment of a protection circuit.

Detailed Description

The present invention will be described in further detail with reference to the following detailed description and accompanying drawings. Wherein like elements in different embodiments are numbered with like associated elements. In the following description, numerous details are set forth in order to provide a better understanding of the present application. However, those skilled in the art will readily recognize that some of the features may be omitted or replaced with other elements, materials, methods in different instances. In some instances, certain operations related to the present application have not been shown or described in detail in order to avoid obscuring the core of the present application from excessive description, and it is not necessary for those skilled in the art to describe these operations in detail, so that they may be fully understood from the description in the specification and the general knowledge in the art.

Furthermore, the features, operations, or characteristics described in the specification may be combined in any suitable manner to form various embodiments. Also, the various steps or actions in the method descriptions may be transposed or transposed in order, as will be apparent to one of ordinary skill in the art. Thus, the various sequences in the specification and drawings are for the purpose of describing certain embodiments only and are not intended to imply a required sequence unless otherwise indicated where such sequence must be followed.

The numbering of the components as such, e.g., "first", "second", etc., is used herein only to distinguish the objects as described, and does not have any sequential or technical meaning. The term "connected" and "coupled" when used in this application, unless otherwise indicated, includes both direct and indirect connections (couplings).

Referring to fig. 1, the present embodiment provides a digital radiography apparatus, including: an X-ray emitter 100, a detector 200, a moving part 300, a dc motor 400, a dc motor driving circuit 500, and a controller 600. The X-ray emitter 100 is used for generating X-rays, the X-rays penetrate through a person to be detected and are received by the detector 200, the detector 200 converts received X-ray signals penetrating through a human body into electric signals and conducts the electric signals to the controller 600, and the controller 600 processes the received electric signals to obtain an X-ray photographic image. The controller 600 is also used to control the dc motor driving circuit 500 to change the direction of current, thereby controlling the dc motor 400 to rotate in the forward or reverse direction. The moving part 300 is connected with the X-ray emitter 100 and/or the detector 200 for driving the X-ray emitter 100 and/or the detector 200 to move, and a power output end of the dc motor 400 is coupled to the moving part 300 for driving the moving part 300 to move. Fig. 1 only shows that the moving component 300 is coupled to the upper portion of the X-ray emitter 100 to move the X-ray emitter 100 relative to the upper wall, including the movement of the X-ray emitter 100 parallel to the wall surface, and also including the movement perpendicular to the wall surface and other directions. In other embodiments, the moving part 300 may also be coupled with other parts of the X-ray emitter 100 to drive the movement of the X-ray emitter 100 in various directions or the movement of a part of the X-ray emitter 100 relative to another part; in other embodiments, the moving member 300 can be connected to different parts of the probe 200 to move the probe 200 in different directions or to move one part of the probe 200 relative to another part. In another embodiment, the moving part may drive the X-ray emitter and the detector to move integrally, that is, in the mobile digital X-ray photographing apparatus, the moving part may be configured to drive the whole mobile digital X-ray photographing apparatus to move. According to different detection requirements, the digital radiography apparatus may be configured with one or more moving components 300, and the moving components 300 may be respectively configured at different positions of the X-ray emitter 100 and/or the detector 200, so as to drive the X-ray emitter 100 or the detector 200 to move in all directions in three-dimensional space, such as up-down, left-right, front-back, and the like. Further, one or more dc motors may be coupled to one of the moving components to achieve movement of the X-ray emitter 100 or the detector 200 in different directions.

Referring to fig. 1 and fig. 2, an input end of the dc motor driving circuit 500 is connected to a dc voltage DIR, and an output end thereof is electrically connected to the dc motor 400 for driving the dc motor 400 to rotate. The direct current motor driving circuit 500 comprises a double-pole double-throw switch K1, wherein two moving ends of a double-pole double-throw switch K1 are respectively connected with a high-potential point and a grounding point, the first stage of the first group of immobile ends of the double-pole double-throw switch K1 is connected with the anode of the direct current motor 400, and the second stage of the first group of immobile ends is connected with the cathode of the direct current motor 400; the first stage of the second group of the fixed ends of the double-pole double-throw switch K1 is connected with the negative pole of the direct current motor, and the second pole of the second group of the fixed ends is connected with the positive pole of the direct current motor. In the embodiment shown in fig. 2, a dc voltage V is connected across the dc motor driving circuit 500_DCThe movable end 1 of the double-pole double-throw switch K1 is connected with a high potential point, the movable end 2 of the double-pole double-throw switch K1 is connected with a grounding point, the first group of immobile ends 4 of the double-pole double-throw switch K1 is connected with the anode of the direct current motor 400, and the first group of immobile ends 3 of the double-pole double-throw switch K1 is connected with the cathode of the direct current motor 400; the second group of immobile terminals 5 of the double-pole double-throw switch K1 is connected with the anode of the DC motor 400, and the second group of immobile terminals of the double-pole double-throw switch K1And 6 is connected with the negative pole of the direct current motor 400.

With continued reference to fig. 1 and 2, the controller 600 is configured to control the two moving terminals of the double-pole double-throw switch K1 to switch between the first and second poles of the two sets of stationary terminals, respectively, so as to cause current to flow through the dc motor 400 in different directions. Referring to fig. 3, specifically, the moving terminal 1 of the double-pole double-throw switch K1 is connected to a high-potential point, the moving terminal 2 of the double-pole double-throw switch K1 is connected to a ground point, under the control of the controller 600, the moving terminal 1 of the double-pole double-throw switch K1 is connected to the first group of the immobile terminals 4, the moving terminal 2 of the double-pole double-throw switch K1 is connected to the second group of the immobile terminals 6, the current driven terminal 1 flows to the positive electrode of the dc motor 400 through the first group of the immobile terminals 4, flows from the positive electrode of the dc motor 400 to the negative electrode, flows into the moving terminal 2 through the second group of the immobile terminals 6 to form a loop, and the dc motor 400 rotates in the forward direction under the action of the current flowing from the positive electrode to the negative electrode thereof. Referring to fig. 4, the moving terminal 1 of the double-pole double-throw switch K1 is connected to a high potential point, the moving terminal 2 of the double-pole double-throw switch K1 is connected to a ground point, under the control of the controller 600, the moving terminal 1 of the double-pole double-throw switch K1 is connected to the first group of stationary terminals 3, the moving terminal 2 of the double-pole double-throw switch K1 is connected to the second group of stationary terminals 5, the current driven terminal 1 flows to the negative electrode of the dc motor 400 through the first group of stationary terminals 3, flows from the negative electrode to the positive electrode of the dc motor 400, flows through the moving terminal 2 through the second group of stationary terminals 5 to flow into the ground point to form a loop, and the dc motor 400 reversely rotates under the action of the current flowing from the negative electrode to the positive electrode thereof.

The connection relationship between the double-pole double-throw switch K1 and other elements is not limited to that shown in fig. 2 to 4, but other connection manners may be adopted, such that the two moving ends of the double-pole double-throw switch K1 are respectively switched between the first stage and the second stage of the two groups of stationary ends to change the direction of the current flowing through the dc motor 400, for example, the moving end 2 of the double-pole double-throw switch K1 is connected to a high potential point, the moving end 1 is connected to a grounding point, the first group of stationary ends 4 is connected to the negative pole of the dc motor 400, and the first group of stationary ends 3 is connected to the positive pole of the dc motor 400; the second group of stationary terminals 5 is connected to the positive pole of the dc motor 400, and the second group of stationary terminals 6 is connected to the negative pole of the dc motor 400. When the moving end 1 of the double-pole double-throw switch K1 is connected with the first group of stationary ends 4 and the moving end 2 is connected with the second group of stationary ends 5, current flows from the positive pole to the negative pole of the direct current motor 400, and the direct current motor 400 rotates in the positive direction; when the moving end 1 of the double-pole double-throw switch K1 is connected to the first group of stationary ends 3 and the moving end 2 is connected to the second group of stationary ends 6, the current flows from the negative pole to the positive pole of the dc motor 400, and the dc motor 400 rotates in the reverse direction.

Referring to fig. 2, in an embodiment, the double-pole double-throw switch K1 is a double-pole double-throw relay, a control terminal of the double-pole double-throw relay is connected to the controller 600, and the controller 600 controls the double-pole double-throw relay to switch. The controller 600 can control the magnetic direction of the magnetic induction coil of the double-pole double-throw relay by controlling the direction of the input voltage of the control end of the double-pole double-throw relay, and push the movement of the movable end so as to change the connection relationship between the movable end and the fixed end. The controller 600 can control the moving end of the double-pole double-throw relay to be connected with different fixed ends respectively so as to change the current flow direction of the direct current motor; or the movable end is controlled not to be connected with the immovable end so as to cut off the current loop of the direct current motor driving circuit.

In the embodiment, the direct current motor driving circuit adopted in the digital X-ray photographing device drives the direct current motor to rotate in the forward direction or the reverse direction, and compared with a mode that an H-bridge structure is adopted in the traditional X-ray photographing device to drive the direct current motor to rotate, the digital X-ray photographing device has the advantages of few power devices, low cost, and simple and convenient circuit implementation and software control.

Referring to fig. 2, in an embodiment, the dc motor driving circuit 500 further includes a power switch Q1, the power switch Q1 is connected in series with the dc motor 400 between a high potential point and a ground point, a control electrode of the power switch Q1 inputs a pulse width modulation signal (PWM signal), the PWM signal can control instantaneous on/off of the power switch Q1, a duty ratio of the PWM signal is adjustable, and stepless speed regulation of the dc motor 400 can be achieved by adjusting the duty ratio of the PWM signal. The power switch Q1 may be a metal-oxide semiconductor field effect transistor (MOSFET) or an Insulated Gate Bipolar Transistor (IGBT), for example, the MOSFET is connected in series with the dc motor 400 between a high potential point and a ground point, in the embodiment shown in fig. 2, the drain of the MOSFET is connected to the moving terminal 2 of the double-pole double-throw switch K1 and connected to the dc motor 400 through the moving terminal 2 and the stationary terminal 5 or 6, the source of the MOSFET is grounded, the gate (i.e., the control electrode) of the MOSFET inputs a PWM signal, and the gate of the MOSFET is controlled by the PWM signal, and the drain and the source of the MOSFET are instantaneously turned on or off, so that the loop of the dc motor 400 is instantaneously turned on or off.

The direct current motor 400 is equivalent to an inductance coil, based on the physical characteristics of the inductance, the current passing through the direct current motor 400 and the voltage at the two ends of the direct current motor 400 do not generate sudden changes, the direct current motor 400 automatically performs chopping, the two ends of the direct current motor 400 are equivalent to direct current voltage which is in direct proportion to the duty ratio of a PWM signal, and when the duty ratio of the PWM signal is adjusted, the average voltage at the two ends of the direct current motor 400 changes accordingly. Specifically, when the PWM has a duty ratio of X%, the average voltage across the dc motor is V_DCX%, since the PWM duty ratio is a digital quantity, theoretically, it can be infinitely subdivided, and thus, stepless regulation of the voltage corresponding to the dc motor 400 can also be achieved. For a direct current motor, the direct current voltages applied to two ends of the direct current motor are different, which causes the difference of the rotating speeds of the direct current motor, the higher the voltage is, the faster the rotating speed is, and conversely, the lower the voltage is, the slower the rotating speed is, the stepless speed regulation of the direct current motor 400 is realized by the stepless regulation of the voltages at the two ends of the direct current motor 400, the stepless speed regulation of the direct current motor 400 also can carry out the stepless regulation of the moving speed of the moving part 300, the X-ray emitter 100 and/or the detector 200 can realize the stable speed change under the driving of the moving part 300 to reach the proper moving speed, so that the X-ray emitter 100 and/or the detector 200 are regulated to the most suitable detection position.

Referring to fig. 2, in an embodiment, the dc motor driving circuit 500 further includes a first resistor R1 and a protection circuit 510, the first resistor R1 is connected in series with the dc motor 400 between a high potential point and a ground point, and the protection circuit 510 is configured to collect a voltage across the first resistor R1 and output the voltage to the controller 600. The series connection of the first resistor R1 and the dc motor 400 may be a series connection directly connected with the dc motor 400; the first resistor R1 may be connected in series indirectly with the dc motor 400, for example, one end of the first resistor R1 is connected to the power switch Q1, and the other end is connected to the ground point, that is, connected in series indirectly with the dc motor 400. According to the movement requirement of the X-ray emitter 100 and/or the detector 200, a certain voltage threshold is set in the controller 600, and when the controller 600 detects that the input voltage value is higher than the preset threshold, a protection control signal is output to cut off the current loop of the DC motor driving circuit 500 or interrupt the power supply of the DC motor driving circuit 500. The first resistor R1 and the protection circuit 510 play a role of overcurrent protection in the dc driving circuit 500, when the current passing through the dc motor 400 increases, the current passing through the first resistor R1 increases, and since U ═ IR increases, the voltage across the first resistor R1 increases accordingly, and the voltage across the first resistor R1 received by the controller 600 and collected by the protection circuit 510 increases accordingly. When the voltage across the first resistor R1 received by the controller 600 is higher than the threshold, it indicates that the current passing through the dc motor 400 is too large, which may cause the risk of burning the motor and other electrical components, and the controller 600 cuts off the current loop of the dc motor driving circuit or cuts off the power supply of the dc motor driving circuit by outputting a protection control signal, so as to prevent the current passing through the dc motor driving circuit from being too large, and thus, the controller plays a role of protecting the whole circuit. In one embodiment, the controller 600 outputs the protection control signal to the double-pole double-throw switch K1, and the double-pole double-throw switch K1 disconnects the moving terminal and the fixed terminal after receiving the protection control signal, so that the dc motor driving circuit is disconnected. In another embodiment, the controller 600 is connected to the signal source of the PWM signal, and when the signal source of the PWM signal receives the protection control signal output by the controller 600, the sending of the PWM signal is terminated, so that the power switch Q1 is turned off, and the current loop of the dc motor driving circuit is cut off. In another embodiment, the dc motor driving circuit further includes a power module, the controller 600 is connected to the power module, and the power module interrupts power supply when receiving a protection control signal output by the controller 600, so as to protect the circuit and the electrical components when the current in the dc motor driving circuit is too large. The present invention is not limited to the above embodiments, and other embodiments may also be implemented to cut off the current loop of the dc motor driving circuit or cut off the power supply of the dc motor driving circuit by outputting the protection control signal through the controller 600.

Referring to fig. 5, in an embodiment, the protection circuit 510 includes an amplifying circuit a1 and an analog-to-digital converter ADC, and the protection circuit 510 is connected to a connection node between the first resistor R1 and the power switch Q1, and is configured to collect and amplify a voltage divided by the first resistor R1; the input end of the analog-to-digital converter ADC is connected with the amplifying circuit A1, and the output end of the analog-to-digital converter ADC is connected with the controller, and the analog-to-digital converter ADC is used for converting the voltage analog signal output by the amplifying circuit into a digital signal and transmitting the digital signal to the controller. The amplifying circuit 510 can amplify the tiny voltage across the first resistor R1, so as to facilitate the collection and analog-to-digital conversion, and improve the accuracy of the overcurrent protection of the protection circuit 510. Further, a follower circuit may be included between the amplifying circuit a1 and the analog-to-digital converter ADC to match the impedance of the amplifying circuit a1 and the analog-to-digital converter ADC.

In one embodiment, the frequency of the PWM signal is greater than or equal to 5kHz and less than or equal to 50kHz, so that the direct current motor driving circuit can meet the design requirements of normal operation and stepless speed change. If the frequency is too low, the chopping effect of the direct current drive motor 400 is not ideal, the motor will vibrate at low frequency, the ripple noise on the armature of the motor is very large, and jamming and pause may occur; if the frequency is too high, the loss of the power switch tube is increased.

The foregoing is a more detailed description of the present application in connection with specific embodiments thereof, and it is not intended that the present application be limited to the specific embodiments thereof. It will be apparent to those skilled in the art from this disclosure that many more simple derivations or substitutions can be made without departing from the inventive concepts herein.

Claims (7)

1. A digital radiography apparatus, comprising:

an X-ray emitter for generating X-rays;

the detector is used for receiving X rays penetrating through a human body and converting the X rays into electric signals;

the moving component is used for driving the X-ray emitter and/or the detector to move;

the power output end of the direct current motor is coupled to a moving part and used for driving the moving part to move;

the input end of the direct current motor driving circuit is connected with direct current voltage, and the output end of the direct current motor driving circuit is electrically connected with the direct current motor and used for driving the direct current motor to rotate; the direct current motor driving circuit comprises a double-pole double-throw switch, two moving ends of the double-pole double-throw switch are respectively connected with a high potential point and a grounding point, the first stage of the first group of immobile ends of the double-pole double-throw switch is connected with the positive pole of the direct current motor, and the second pole of the first group of immobile ends is connected with the negative pole of the direct current motor; the first stage of the second group of immobile ends of the double-pole double-throw switch is connected with the negative pole of the direct current motor, and the second pole of the second group of immobile ends is connected with the positive pole of the direct current motor;

and the controller is used for controlling the two movable ends of the double-pole double-throw switch to be switched between the first pole and the second pole of the two groups of fixed ends respectively so as to enable the current to flow through the direct current motor in different directions.

2. The digital radiography apparatus as claimed in claim 1, wherein said dc motor driving circuit further comprises a power switching tube, said power switching tube and said dc motor are connected in series between a high potential point and a ground point, a control electrode of said power switching tube inputs a PWM signal to control instantaneous on/off of said power switching tube, and a duty ratio of said PWM signal is adjustable.

3. The digital X-ray photographing apparatus of claim 1, wherein the dc motor driving circuit further comprises a first resistor and a protection circuit, the first resistor being connected in series with the dc motor between a high potential point and a ground point; the protection circuit collects voltages at two ends of the first resistor and outputs the voltages to the controller, and the controller is used for outputting a protection control signal when the voltages at the two ends of the first resistor are higher than a preset threshold value so as to cut off a current loop of the direct current motor driving circuit or cut off the power supply of the direct current motor driving circuit.

4. The digital radiography apparatus of claim 3 wherein the protection circuitry comprises amplification circuitry and an analog-to-digital converter;

the amplifying circuit is connected with the first resistor in parallel and used for acquiring and amplifying voltages at two ends of the first resistor;

the input end of the analog-to-digital converter is connected with the amplifying circuit, and the output end of the analog-to-digital converter is connected with the controller and used for performing analog-to-digital conversion on the voltage output by the amplifying circuit and transmitting the voltage to the controller.

5. The digital radiography apparatus of claim 3 wherein the protection control signal is used to control PWM signal interrupts.

6. The digital radiography apparatus of claim 2 wherein the PWM signal has a frequency of 5kHz or more and 50kHz or less.

7. The digital radiography apparatus of any one of claims 1-6 wherein said double-pole double-throw switch is a double-pole double-throw relay; the control end of the double-pole double-throw relay is connected with the controller, and the controller controls the double-pole double-throw relay to be switched.

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