JPH10294160A - Slidingly movable contact point mechanism and x-ray ct device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a short circuit between contact brushes by arranging mutual ones to contact with adjacent conductors of translating plural contact brushes in positions different by a distance corresponding to a length of at least the brushes in the direction of a line. SOLUTION: Data and a signal of a transmitter of a communication device related to X-ray transmission data, are respectively transmitted to a receiver through rings Rd to Rc' of a slip ring mechanism RNGd and contact pieces CNTd to CNTc' of brushes Bd to Bc'. Here, installing positions of brushes Bd', Bs' and Bc' to a brush holder BHL are respectively arranged so as to be dislocated by a distance not less than a length of respective contact pieces CNTd', CNTs' and CNTc' more than the brushes Bd, Bs and Bc. Therefore, brushes Rd to Rc' are installed in the brush holder DHL in the relative arrangement relationship that the mutual brushes to contact with the adjacent rings are not juxtaposed just besides each other, and even if abrasion powder is generated by sliding motion between the rings and the brushes B and sticks to the contact pieces, a short circuit between the mutual contact pieces by the abrasion powder can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sliding contact mechanism and an X-ray CT apparatus, and more particularly, to a sliding contact mechanism in which a short circuit between contact brushes is unlikely to occur and an X-ray CT using such a sliding contact mechanism. Related to the device.

[0002]

2. Description of the Related Art For example, an X-ray C that performs a scan by continuously rotating an X-ray irradiation / detection system around a subject is described.
In a T (computed tomography) device, detection data (transmitted X-ray data) is transmitted from an X-ray irradiation / detection system mounted on a rotating unit to a data processing system disposed on a fixed unit.
Is transmitted via a slip ring mechanism.

[0003] The slip ring mechanism includes a conductor forming an annular line (ring) and a contact brush (brush) contacting the conductor. One of the ring and the brush is disposed on the rotating unit side, and the other is disposed on the fixed unit side. As the rotating part rotates, the brush slides on the ring, and an electric signal representing detection data is transmitted through the sliding contact part.

[0004] Two rings and two brushes are used per signal system in accordance with two signal lines for signal current reciprocation. Then, two rings and two brushes are added in accordance with the increase of the signal system.

[0005] A plurality of rings are arranged parallel to one another.
As the form of the parallel arrangement, there are a case where they are arranged concentrically on a plane and a case where they are arranged side by side on a cylindrical surface. A plurality of brushes are arranged in parallel corresponding to such a plurality of rings.

[0006] The interval between adjacent rings is made as small as possible to avoid unnecessary enlargement of the slip ring mechanism. As the ring interval decreases, the interval between adjacent brushes also decreases.

[0007]

The brush gradually wears due to sliding with the slip ring, and generates abrasion powder. Abrasive powder scatters around, but some adhere to the brush. If the amount of abrasion powder adhering to the brush increases with prolonged operation, a short circuit may occur between adjacent brushes due to the abrasion powder. If the brushes are short-circuited, the signal transmission becomes abnormal and a correct signal is not transmitted. In addition, if the brush interval is small, a short circuit due to dust easily occurs.

Such a problem is not limited to the slip ring mechanism of the X-ray CT apparatus, but is a problem common to a sliding contact mechanism having a plurality of conductors forming a parallel line and a plurality of contact brushes respectively contacting the conductors.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide a sliding contact mechanism in which a short circuit between contact brushes is unlikely to occur, and a short circuit between contact brushes in the sliding contact mechanism. An object of the present invention is to realize a difficult X-ray CT apparatus.

[0010]

[Means for Solving the Problems]

[1] A first invention for solving the above-mentioned problem is a plurality of parallel conductors each forming a line, and a plurality of conductors which respectively contact with the plurality of conductors and relatively translate along the line along the line. A sliding contact mechanism comprising a contact brush, wherein the plurality of contact brushes that contact at least adjacent conductors differ by a distance corresponding to at least a length of the brush along the direction of the line. The conductor contacts the conductor at a position.

In the first invention, the plurality of conductors are:
It is preferable to form a ring-shaped line from the viewpoint of obtaining a rotary sliding contact mechanism. In this case, it is preferable that the annular line be concentric on substantially the same plane in order to reduce the dimension of the sliding contact mechanism in the rotation axis direction.

In addition, it is preferable that the ring-shaped line forms a parallel ring on substantially the same cylindrical surface in order to obtain a sliding contact mechanism having a small dimension in the rotational radius direction. [2] A second invention for solving the above-mentioned problem is an X-ray irradiation / detection system which is provided on a rotating unit side and irradiates an object with an X-ray beam to detect transmitted X-rays. A slip ring mechanism for transmitting the transmitted X-ray detection signal to a fixed part side, and an image for generating an image based on the transmitted X-ray detection signal transmitted through the slip ring mechanism provided on the fixed part side X-ray CT apparatus having a generating means, wherein the slip ring mechanism comprises a plurality of parallel conductors each forming an annular line, and a plurality of parallel conductors respectively contacting the plurality of conductors and moving along the lines and relative to the conductors. A plurality of contact brushes that translate in a parallel manner, wherein the plurality of contact brushes are at least ones that contact adjacent conductors,
In the second invention, the ring-shaped lines are substantially the same as each other at positions different from each other by at least a distance corresponding to the length of the brush along the direction of the lines. It is preferable to form a concentric circle on the plane from the viewpoint of reducing the dimension of the slip ring mechanism in the rotation axis direction.

(Operation) The contact brushes that contact the conductors of the adjacent lines are in contact with the conductors at least by a distance corresponding to the length of the brush along the direction of the line, so that the contact brushes adjacent to each other are contacted. There is no possibility of short-circuiting between the contact brushes due to abrasion powder or the like because they do not line up next to each other.

[0014]

Embodiments of the present invention will be described below in detail with reference to the drawings. Note that the present invention is not limited to the embodiment.

FIG. 1 shows a block diagram of an X-ray CT apparatus.
This device is an example of an embodiment of the present invention. Note that the configuration of the present apparatus shows an example of an embodiment relating to the apparatus of the present invention.

(Configuration) The configuration of the present apparatus will be described. As shown in FIG. 1, the X-ray CT apparatus 100 includes an operation console (c
An onsole 1, an imaging table 10, and a scanning gantry 20 are provided.

The operation console 1 includes an input device 2 for inputting operator's instructions and information, a central processing unit 3 for performing scan control and image reconstruction, and a control table for transmitting control signals and the like.
0 or a control interface (i
nterface) 4, a data collection buffer (buffer) 5 for collecting data acquired by the scanning gantry 20,
A CRT (cathod-ray tube) 6 for displaying images and the like, and a storage device 7 for storing various data, reconstructed images, programs and the like are provided.

The central processing unit 3 is, for example, a computer (c
omputer). Data collection buffer 5
, Data acquired by the scanning gantry 20 is input through a communication device (not shown). The communication device will be described later.

The imaging table 10 carries a subject (not shown) into and out of the X-ray irradiation space of the scanning gantry 20. The movement of the photographing table 10 is controlled by the control interface 4.

The scanning gantry 20 includes an X-ray tube 30 and a collimator 50 for forming an X-ray beam.
And a detector array 60 and an X-ray controller 2 for adjusting the timing and dose of X-ray irradiation
1 and the X-ray passing aperture of the collimator 50 (aperture (ape
rture)), a data collection unit 23 that collects data detected by the detector array 60, and a rotation that rotates the X-ray tube 30, the detector array 60, and the like around the body axis of the subject. And a controller 24.

The X-ray controller 21, the collimator controller 22, the data collection unit 23, and the rotation controller 24 are controlled by control signals given from the control interface 4 through a communication device (not shown). The control interface 4 is also provided for each of these units.
Recognize each control state based on a status signal provided from the communication device through the communication device. The communication device will be described later.

FIG. 2 shows the relationship between the X-ray tube 30, the collimator 50, and the detector array 60. 2A is a front view, and FIG. 2B is a side view. The X-ray radiated from the X-ray tube 30 is shaped into a flat fan-shaped X-ray beam Xr by the collimator 50 and irradiated to the detector array 60.

The subject is carried in with the body axis crossing the fan surface of the X-ray beam Xr. This state is shown in FIG. As shown in the figure, a slice (sl) is formed by a fan-shaped X-ray beam Xr.
The projected image of the iced object OB is projected on the detector array 60. The thickness of the X-ray beam Xr at the isocenter of the object OB gives the slice thickness th. The slice thickness th is adjusted by the aperture of the collimator 50.

The X-ray tube 30, collimator 50 and detector array 60 rotate (scan) around the object OB while maintaining this relationship. X-ray tube 30, collimator 50,
The detector array 60 and the data collection unit 23 are an example of an embodiment of an X-ray irradiation / detection system according to the present invention.

A plurality (for example, 10
The projection data of the subject is collected at the view angle of (00). The collection of the projection data is performed by a system including the detector array 60, the data collection unit 23, the communication device, and the data collection buffer 5.

Based on the projection data collected in the data collection buffer 5, the central processing unit 3 performs image generation (image reconstruction). The central processing unit 3 is an example of an embodiment of an image generating unit according to the present invention. The image reconstruction is performed by, for example, performing filtered back-projection processing on projection data of, for example, 1000 views obtained by one rotation scan.

The reconstructed image, that is, the tomographic image of the object OB is stored in the storage device 7. The tomographic image stored in the storage device 7 is read out according to a command given by an operator through the input device 2 and displayed on the CRT 6 as a visible image.

FIG. 4 is a block diagram of a communication device relating to X-ray transmission data. As shown in FIG.
It has a transmitter TRNd, a slip ring mechanism RNGd, and a receiver RCVd. Slip ring mechanism RNGd
Is an example of an embodiment of the sliding contact mechanism of the present invention.
It is also an example of an embodiment of a slip ring mechanism.

The slip ring mechanism RNGd has a pair of rings Rd and Rd 'and a pair of brushes Bd and Bd' respectively contacting the rings. The rings Rd and Rd 'are bare conductors concentric with the orbit of rotation of the X-ray irradiation / detection system. These rings Rd, Rd ′ are arranged on the rotating part side of the scanning gantry 20. The brushes Bd and Bd ′ are disposed on the fixed part side of the scanning gantry 20. Brush Bd,
Bd 'relatively translates on the rings Rd, Rd' as the rotating part rotates.

The transmitter TRNd is mounted on the rotating part of the scanning gantry 20. The output of the transmitter TRNd is connected to the rings Rd, Rd '. The receiver RCVd is arranged in the scanning console 1. The input end of the receiver RCVd is connected to brushes Bd and Bd '.

Transmitted X-ray data is input from the data collection unit 23 to the transmitter TRNd. Input data is 16
It is parallel data of a bit (bit). The transmitter TRNd converts the input data into a serial signal and outputs the serial signal to the slip ring mechanism RNGd.

The output signal of the transmitter TRNd is
The signal is input to the receiver RCVd through a contact portion between d and Rd ′ and the brushes Bd and Bd ′. The receiver RCVd converts the input serial signal into parallel data and inputs the parallel data to the data collection buffer 5.

FIG. 5 shows a block diagram of a communication device relating to the status signal. As shown in the figure, the communication device related to the status signal has the same configuration as the communication device shown in FIG. Therefore, the same reference numerals are given to the same parts, and the description will be omitted. However, the suffix of the code is changed from d to s for distinction. Slip ring mechanism RNGs
Is an example of an embodiment of the sliding contact mechanism of the present invention.
It is also an example of an embodiment of a slip ring mechanism.

The transmitter TRNs has an X-ray controller 2
1. Status signals of the collimator controller 22, the data collection unit 23, and the rotation controller 24 are input. The status signal is, for example, a 16-bit parallel signal. The transmitter TRNs converts an input signal into a serial signal and outputs the serial signal to the slip ring mechanism RNGs.

The output signal of the transmitter TRNs is
The signal is input to the receiver RCVs through a contact portion between s, Rs 'and the brushes Bs, Bs'. The receiver RCVs converts an input serial signal into a parallel signal and inputs the signal to the control interface 4.

FIG. 6 shows a block diagram of a communication device relating to control signals. As shown in the figure, the communication device includes a transmitter TRNc, a slip ring mechanism RNGc, and a receiver RCV.
c. The slip ring mechanism RNGc is an example of an embodiment of the sliding contact mechanism according to the present invention. Also,
It is an example of an embodiment of a slip ring mechanism.

The slip ring mechanism RNGc is similar to the slip ring mechanisms RNGd and RNGs shown in FIGS.
It has the same configuration as. The transmitter TRNc is arranged in the scanning console 1. The output end of the transmitter TRNc is connected to brushes Bc and Bc '. Receiver RCV
“c” is mounted on the rotating unit side of the scanning gantry 20. The input end of the receiver RCVc is connected to the rings Rc, Rc '.

The control interface 4 is provided to the transmitter TRNc.
Receives a control signal. The input signal is, for example, a 16-bit parallel signal. The transmitter TRNc converts an input signal into a serial signal and outputs the serial signal to the rings Rc and Rc 'through the brushes Bc and Bc'.

The output signal of the transmitter TRNc is
Input to the receiver RCVc via c and Rc '. The receiver RCVc converts an input serial signal into a parallel signal, and converts the serial signal into an X-ray controller 21 and a collimator controller 2.
2. The data is supplied to the data collection unit 23 and the rotation controller 24.

Rings Rd, Rd ', Rs, Rs', R
As shown in FIG. 7, for example, c and Rc ′ are disposed concentrically on a plate-shaped support member SPT. Support member SP
T is made of, for example, an insulating material such as a synthetic resin.
Rings Rd, Rd ', Rs, Rs', Rc, Rc'
It is an example of an embodiment of a conductor in the present invention.

The support member SPT has a hole HOL which is concentric with the rings Rd to Rc '. The size of the hole HOL is, for example, such that the trunk of the subject can pass through. The support member SPT is attached to the fixed portion side of the scanning gantry 20, and is configured to rotate around the center of the hole HOL.

A brush unit BRS is provided in engagement with the rings Rd to Rc '. The brush unit BRS is attached to the fixed portion side of the scanning gantry 20, and faces the rings Rd to Rc 'on the support member SPT.

FIG. 8 is a schematic view showing an engagement state between the rings Rd to Rc ′ and the brush unit BRS. (A) of FIG.
Is a plan view, and (b) is a side view. As shown in the figure,
The brush unit BRS includes brushes Bd to Bc ′ and a brush holder BHL that supports them. The brush holder BHL is made of, for example, an insulating material such as a synthetic resin. The brushes Bd to Bc 'are an example of an embodiment of the contact brush in the present invention.

The brush Bd includes a contact piece CNTd and a leaf spring S
PRd. The contact piece CNTd is an example of an embodiment of the brush in the present invention. Contact piece CNT
d is formed using, for example, a silver alloy or the like. Leaf spring SPR
d is composed of, for example, phosphor bronze. Each of them has conductivity.

The contact piece CNTd is formed in a substantially rectangular parallelepiped. The leaf spring SPRd is formed in an elongated plate shape. The back surface of the contact piece CNTd is fixed to the plate surface at one end of the leaf spring SPRd. Leaf spring SPRd
Is fixed to the brush holder BHL.

The contact piece CNTd is in contact with the ring Rd on the side opposite to the side fixed to the leaf spring SPRd. The ring Rd is constituted by a strip conductor. The belt-shaped conductor is plated with, for example, silver. Thereby, the electrical contact with the contact piece CNTd is improved. The width of the strip conductor is slightly wider than the width of the contact piece CNTd. Thus, the entire width of the contact piece CNTd can be effectively used as the width of the contact portion.

The distance from the surface of the ring Rd to the brush holder BHL is such that the leaf spring SPRd is bent by a predetermined amount. Thus, the contact piece CNTd comes into contact with the ring Rd at a predetermined pressure.

The above-described configuration includes the brush Bd 'and the ring Rd', the brush Bs and the ring Rs, the brush Bs 'and the ring Rs', the brush Bc and the ring Rc, and the brush B
The same applies to c ′ and ring Rc ′. However, the attachment positions of the brushes Bd ′, Bs ′ and Bc ′ to the brush holder BHL are shifted along the ring from the brushes Bd, Bs and Bc, respectively.

The amount of displacement of the mounting position is determined by the contact piece C
It is longer than the lengths of NTd ', CNTs' and CNTc'. As a result, the brushes Rd to Rc ′ are attached to the brush holder BHL in a relative positional relationship in which the contact pieces of the brushes that contact the adjacent rings are not arranged side by side.

(Operation) The operation of the present apparatus will be described. The X-ray CT apparatus 100 starts scanning according to a command given by the operator through the input device 2. That is, the X-ray irradiation / detection system rotates around the subject, and the X-ray transmission data in a plurality of views is collected by the data collection unit 23. The collected data is transmitted to the data collection buffer 5 by a communication device interposed by the slip ring mechanism RNGd.

A control signal for performing a scan is transmitted from the control interface 4 to the X-ray controller 21, the collimator controller 22, the data acquisition unit 23 and the rotation controller 24 in the scanning gantry 20 by a communication device interposed by the slip ring mechanism RNGc. Given. The status signal of each unit is transmitted to the control interface 4 by a communication device in which the slip ring mechanism RNGs intervenes.

The central processing unit 3 reconstructs an image based on the data collected in the data collection buffer 5 by, for example, a filtered back projection method. The reconstructed image is stored in the storage device 7 and displayed on the CRT 6 based on an instruction from the operator.

The slip ring mechanisms RNGd, RNGs,
In RNGc, each time a scan is performed, the rings Rd-R
c ′ and the brushes Bd to Bc ′, the brush Bd
Abrasion powder of the contact pieces CNTd to CNTc ′ is generated and adheres to the contact pieces CNTd to CNTc ′.

The amount of the abrasion powder attached increases as the scan time is integrated. Wear powder, contact piece CNTd ~ CNT
Depending on the material of c ′, some may adhere to the side surfaces of the contact pieces CNTd to CNTc ′ and grow in the shape of a needle toward the next.

Even in such a case, in the slip ring mechanism of the present apparatus, as shown in FIG. 8, the contact pieces of the adjacent brushes are displaced along the ring so that they do not line up side by side. Therefore, even if the accumulation of the abrasion powder attached to the side surface of the contact piece grows in a needle shape, a short circuit does not occur between adjacent brushes.

Further, since there is a sufficient distance between the brush and the adjacent brush, it is extremely unlikely that the accumulation of needle-like abrasion powder grows as short as this distance. Further, the abrasion powder adhering to the front surface or the rear surface of the contact piece does not cause a short circuit between the brushes. The same applies to dust attached to the brush.

As described above, the present apparatus is less likely to cause a short circuit of the brush due to abrasion powder or the like. Note that the slip ring mechanism is not limited to the one in which the ring is disposed on the plate-shaped support member as shown in FIG. 7, but may be, for example, a cylindrical support member SPT ′ as shown in FIG. May be juxtaposed in the axial direction of the cylinder. This configuration is preferable in that the radial size of the slip ring mechanism is reduced. On the other hand, the configuration shown in FIG. 7 is preferable in that the size in the axial direction is reduced.

The conductor line need not necessarily form a ring, but may be an open loop line having both ends. In the slip ring mechanism or the sliding contact mechanism as described above, the brush may be moved instead of the ring or the line conductor.

[0059]

As described above in detail, according to the present invention, at least the length of the contact brush corresponding to at least the length of the brush along the direction of the line formed by the conductor is at least between those contacting the adjacent conductor. Since the conductors are brought into contact with each other at a distance, it is possible to realize a sliding contact mechanism in which a short circuit between the contact brushes does not easily occur, and an X-ray CT apparatus in which a short circuit between the contact brushes in the sliding contact mechanism does not easily occur. .

[Brief description of the drawings]

FIG. 1 is a block diagram of a device according to an example of an embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of an X-ray irradiation / detection system in an apparatus according to an embodiment of the present invention.

FIG. 3 is a schematic configuration diagram of an X-ray irradiation / detection system in an apparatus according to an embodiment of the present invention.

FIG. 4 is a block diagram of a communication device according to an example of an embodiment of the present invention.

FIG. 5 is a block diagram of a communication device according to an example of an embodiment of the present invention.

FIG. 6 is a block diagram of a communication device according to an example of an embodiment of the present invention.

FIG. 7 is a schematic configuration diagram of a slip ring mechanism in the communication device.

FIG. 8 is a schematic diagram showing an engagement state between a ring and a brush in the slip ring mechanism.

FIG. 9 is a schematic diagram showing another example of the ring arrangement in the slip ring mechanism.

[Explanation of symbols]

 Reference Signs List 100 X-ray CT apparatus 1 Operation console 2 Input device 3 Central processing unit 4 Control interface 5 Data acquisition buffer 6 CRT 7 Storage device 10 Imaging table 20 Scanning gantry 21 X-ray controller 22 Collimator controller 23 Data collection unit 24 Rotation controller 30 X-ray Tube 50 Collimator 60 Detector array OB Subject TRNd to TRNc Transmitter RNGd to RNGc Slip ring mechanism RCVd to RCVc Receiver Rd to Rc 'Ring Bd to Bc' Brush SPT Support member BRS Brush unit BHL Brush holder CNTd to CNTd 'Contact SPRd, SPRd 'leaf spring

Claims (2)

[Claims] 1. A sliding contact comprising: a plurality of parallel conductors each forming a line; and a plurality of contact brushes respectively in contact with the plurality of conductors and relatively translating along the line with respect to the conductor. In the mechanism, the plurality of contact brushes, at least ones that contact adjacent conductors, contact the conductor at positions different at least by a distance corresponding to the length of the brush along the direction of the line. A sliding contact mechanism, characterized in that: 2. An X-ray irradiation / detection system disposed on a rotating unit side for irradiating an object with an X-ray beam to detect transmitted X-rays, and detecting the transmitted X-ray from the rotating unit side to a fixed unit side. An X-ray CT apparatus, comprising: a slip ring mechanism for transmitting a signal; and an image generating unit disposed on the fixed portion side and generating an image based on the transmitted X-ray detection signal transmitted through the slip ring mechanism. The slip ring mechanism comprises: a plurality of parallel conductors each forming an annular line; and a plurality of contact brushes respectively in contact with the plurality of conductors and relatively translating along the lines with respect to the conductors. Wherein the plurality of contact brushes contact the conductor at positions different from each other by at least a distance corresponding to at least a length of the brush along the direction of the line along the direction of the line. An X-ray CT apparatus, which is in contact with the apparatus.