JPH0478297B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a CT scanner in a CT apparatus, and more particularly to a CT scanner equipped with a slip ring having a rail and a brush that slides on the rail.

[Technical background of the invention and its problems]

2. Description of the Related Art Conventionally, some CT scanners, such as X-ray CT scanners, have a donut-shaped slip ring assembly having an inner diameter large enough to allow a subject to be inserted into the scanner body. The slip ring assembly enables continuous rotation of the X-ray tube within the scanner body, and is identical to the circular object insertion hole (not shown) in the scanner body, as shown in FIG. A donut plate-shaped rail 1 having a center and an inner diameter larger than the diameter of the subject insertion hole, and a brush portion having a brush 3 that slides on a plate-shaped surface 2 of the rail 1. The rail 1 is electrically connected to an X-ray tube (not shown), and the brush 3 is electrically connected to a high voltage generator (not shown). Since the brush 3 is relatively movable on the plate-like surface 2 of the rail 1, a high voltage supplied from a high voltage generator is applied to the X-ray tube held on the rail 1. can continuously rotate around the subject insertion hole.

However, since the brush 3 is provided on the circumference having a constant radius R from the center of the subject insertion hole, sliding marks are formed on the plate-like surface 2 of the rail 1, This results in poor contact with the brush 3. Then, the rail 1 or the brush 3 needs to be replaced within a short period of time.

[Purpose of the invention]

This invention was made in view of the above-mentioned circumstances, and by preventing the formation of sliding marks caused by brushes on the rails of slip springs, it is possible to prolong the life of the rails and to prevent the The purpose of the present invention is to provide a CT scanner that can prolong the time required for maintenance and inspection.

[Summary of the invention]

The outline of this invention for achieving the above object is as follows:
holding a brush and an X-ray tube electrically connected to a high voltage generator and electrically connected to the X-ray tube;
A slip ring having an annular rail having an inner diameter larger than the specimen insertion hole, and the brush can be automatically slid along the radial direction of the rail in accordance with the amount of rotation between the brush of the slip ring and the rail. The brush driving means is characterized in that the contact locus of the brush on the rail surface is enlarged.

[Embodiments of the invention]

An embodiment of the invention will be described with reference to the drawings.

FIG. 2 is an explanatory view showing one embodiment of the present invention, and FIG. 3 is a schematic sectional view showing an example of the configuration of a slip ring and a brush in the embodiment.

As shown in FIG. 2, a CT scanner, such as an X-ray CT scanner, which is an embodiment of the present invention has a slip ring 4 and a brush portion driving means 5.

The slip ring 4 has a donut plate-shaped rail 6 which has the same center O as a circular subject insertion hole (not shown) in the X-ray CT scanner and has an inner diameter r larger than the diameter of the subject insertion hole.
and, as shown in FIG. 3, a brush portion 9 that holds a plurality of brushes 7 on a support member 8 that can come into contact with the donut plate-shaped surface of the rail 6. The rail 6 holds an X-ray tube (not shown) and is electrically connected to the slip ring rotation drive unit 10.
is configured to rotate around a subject insertion hole (not shown). Further, the brush portion 9 is electrically connected to a high voltage generator (not shown).
Therefore, a high voltage is applied to the X-ray tube (not shown) by the high voltage generator via the slip ring 4, and it can rotate around the subject insertion hole as the rail 6 rotates. .

The brush part driving means 5 includes a detector 11 that detects the rotation of the rail 6, and a brush 7 that detects the locus of the brush 7 formed on the donut plate-shaped surface of the rail 6 every time the rail 6 rotates as detected by the detector 11. Differently, the brush part 9 is configured to include a drive part 12 that drives the brush part 9 in a reciprocating manner along the radial direction of the inner diameter (or outer diameter) of the rail 6.

In the X-ray CT scanner configured as described above, after a subject is placed in the subject insertion hole (not shown), the rail 6 is rotated by the slip ring rotation drive section 10.
By rotating around the center, the X-ray tube rotates around the subject. Then, by applying a high voltage to the X-ray tube in a pulsed manner from a high voltage generator (not shown), X-rays are intermittently irradiated from the X-ray tube rotating around the subject. On the other hand, the detector 1 in the brush part driving means 5
1 detects the rotation of the rail 6, and the drive unit 12
As a result, the brush portion 9 is reciprocated along the radial direction of the rail 6 so that the locus of the brush 7 formed on the donut plate-shaped surface of the rail 6 differs every time the rail 6 rotates. Therefore, since the locus of the brush 7 differs each time the rail 6 rotates, specific sliding marks are no longer formed on the donut plate-shaped surface of the rail 6, which helps extend the life of the slip ring 4. can be achieved.

Although one embodiment of this invention has been described in detail above, this invention is not limited to the above embodiment, and it goes without saying that it can be implemented with appropriate modifications within the scope of the gist of this invention. Nor.

In place of the brush unit driving means 5 in the previous embodiment, a second embodiment includes a detector that counts the cumulative number of revolutions of the rail 6 and outputs a detection signal when a predetermined number of revolutions is counted, and a detector that outputs a detection signal when a predetermined number of revolutions is counted. Until the detection signal is input, the brush part 9 must be connected to the rail 6.
Instead of moving the brush part 9 along the radial direction of the rail 6, a brush part driving means may be provided that has a driving part that slightly moves the brush part 9 along the radial direction of the rail 6 in response to input of a detection signal.

Furthermore, the configuration shown in FIG. 4 can be cited as a third embodiment.

The brush portion driving means 5 shown in FIG. 4 includes a deceleration mechanism 13 that decelerates the rotational motion output from the slip ring rotational drive portion 10, and a cam reciprocating mechanism or a link reciprocating mechanism to reduce the rotational motion output from the deceleration mechanism 13. The drive unit 14 converts the movement into a reciprocating motion and enables the brush portion 9 to reciprocate so that the locus of the brush 7 differs each time the rail 6 rotates.

[Effects of the Invention] According to the present invention, the contact locus of the brush sliding on the donut plate-shaped surface of the rail spreads over the entire range on the donut plate-shaped surface. By preventing the formation of movement marks and preventing uneven wear of the rail, the life of the slip ring can be extended, and the periodic inspection period of the CT scanner can be extended.

[Brief explanation of drawings]

Figure 1 is an explanatory diagram showing a conventional slip ring.
FIG. 2 is an explanatory diagram showing one embodiment of the present invention, and FIG.
The figure is a schematic cross-sectional view showing an example of the structure of the slip ring and brush in the embodiment, and FIG. 4 is an explanatory diagram showing another embodiment of the present invention. 3...Brush, 4...Slip ring, 5...
Brush unit driving means, 6...Rail, 9...Brush unit.

Claims (1)

[Claims] 1 A slip ring having a brush that is electrically connected to a high voltage generator, and an annular rail that holds an X-ray tube, is electrically connected to the X-ray tube, and has an inner diameter larger than the specimen insertion hole. , a detection means for detecting the amount of rotation between the brush of the slip ring and the rail, and when the amount of rotation detected by the detection means reaches a predetermined value, the brush can be automatically slid along the radial direction of the rail. and a brush driving means that drives the brush to extend the contact locus of the brush on the rail surface.
CT Sukyana.