JPH0479431B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a collimator exchange device for a detector of a scintillation camera.

[Technical background of the invention and its problems] This scintillation camera detects radiation emitted from the body by administering a medicine containing a radioisotope to the human body and converting it into light using a scintillator housed in a detector from outside the body. , which records the distribution of radiation within the body. Such a scintillation camera generally has a configuration as shown in FIG. That is, a hollow support 2 is fixed upright to a base 1 fixed to a floor surface, and a lifter 3 that slides in the vertical direction is built into the hollow portion of this support 2. Further, one end of an arm 4 is fixed to one side of the lifter 3, and a detector 5 is supported at the other end by a support shaft 6 so as to face a subject (not shown). Note that this detector 5 is connected to the arm 4.
It is rotatably supported around a support shaft 6. In addition, this detector 5 is extremely heavy and
Although it has a weight of 600 to 800 [Kg], a lead screw mechanism (not shown) is provided in the support column 2 so that it can withstand this weight and be positioned at any height. The acting force is transmitted to the lifter 3. Further, a collimator 7 is supported on the lower surface of the detector 5, and is used to collimate radiation emitted from a subject to whom a radioisotope has been administered and guide it to the detector. The type of isotope to be used,
Depending on the location of administration of the isotope to the subject,
Generally, one suitable for each case is used. For this reason, various collimators are replaced during the diagnosis process, but as is well known, these collimators are extremely heavy because they are made of materials such as lead, and usually weigh between 50 and 200 kg. Because of their weight, they are often placed on a trolley as shown in FIG. 2 for replacement.

FIG. 2a shows a plan view, and FIG. 2b shows a front view. As shown in these figures, the top plate 8 has a triangular shape.
Legs 9 are fixed to each corner, and casters 10 are provided at the ends. Also, three blocks 11 are fixed on the top plate 8,
A collimator 7 is placed on this block 11. The collimator exchange cart 12 having such a configuration is transported directly below the detector 5 of the scintillation camera shown in FIG. Gradually lower the detector 5, taking care to engage the guide holes 7a, 7b, and 7c formed in the collimator 7. After checking that the detector 5 and collimator 7 are in close contact, tighten the screws to each of the protrusions. In this way, the collimator 7 was brought into close contact with the collimator 7.

In such a conventional collimator exchange device, since the collimator is exchanged with the detection surface facing downward, there is a risk of the collimator falling, which is very dangerous. In addition, it is very difficult to align the collimator and detector and adjust the parallelism when installing the collimator. There is a risk of injury. Furthermore, since the speed reducer for raising and lowering the detector is heavy, its reduction ratio is generally set to a large value, and the speed of raising and lowering the detector is very slow. Therefore, it takes a long time to lower the detector to a position where the collimator can be replaced, which has been a problem.

[Object of the invention] The present invention has been made in view of the above circumstances, and
It is an object of the present invention to provide a collimator exchange device that allows collimator exchange to be performed extremely easily.

[Summary of the Invention] In order to achieve the above-mentioned object, the present invention includes a movable truck portion, a support provided on the truck portion,
a collimator support member that removably supports the collimator with pins that engage in recesses provided on both sides of the collimator and a locking member that prevents rotation of the collimator about the pins; The collimator support member is characterized by being provided with an elevating means for elevating and lowering the collimator support member relative to the detector facing upward for replacement.

Further, the elevating member includes a parallelogram link whose one side is a part of the collimator support member and the opposite side is a part of the support column, and the elevating member has a parallelogram link having one side formed by a part of the collimator support member and the opposite side thereof from a part of the support column. , the collimator is raised and lowered substantially in parallel.

[Embodiments of the Invention] Hereinafter, FIG. 3 shows the configuration of an embodiment of the present invention using a rectangular detector and a rectangular collimator.
This will be explained with reference to FIGS. 4 and 5.

First, in one embodiment of the present invention, two vertical bars 20
The base part 20 is constructed by fixing four casters 21a and 21b to the lower parts of the four corners of the base part 20, which has a frame-like structure made up of a frame and two horizontal bars 20b (one not shown).
It allows you to run freely. In addition, this base portion 20
Two upright columns 22a,
22b is fixed, and a shaft 2 is attached to the upper part of this support 22.
3 passes through the pillars 22a and 22b and the bearing 24
This shaft 23
One ends of lower arms 25a and 25bb, which form the lower sides of the parallel link mechanism, are fixed by bolts V to both penetrating ends of the parallel link mechanism. and pillar 22
Bearings 26a (not shown) and 26b are provided inside slightly above the penetrating portion of the shaft 23 in a and 22b, and rotatable shafts 27a (not shown) and 27b are connected from these bearings 26a and 26b. It stands out. These shafts 27a and 27b are connected to an upper arm 2 that forms the upper side of the parallel link mechanism described above.
One ends of 8a and 28b are each fixed with a bolt V.

The other ends of the upper arm 28a and the lower arm 25a of the parallel link mechanism are pivotally supported by one end of an L-shaped collimator support arm 29a,
Similarly, the other ends of the upper arm 28b and the lower arm 25b are pivotally supported by one end of a collimator support arm 29b, which is also L-shaped.
In addition, these collimator support arms 29a, 29
Pins 30a and 30b are provided through the other end of b, respectively, and these pins 30a and 30b
The through ends 300a and 300b are the collimator 3
Recesses 32a, 32 formed on corresponding both side surfaces of 1
b, respectively, and are pivotally supported. Here, concave portions 32 formed on both sides of the collimator 31
a, 32b are formed slightly shifted toward the column 22 from the imaginary line passing through the center of gravity of the collimator 31, so that the collimator support arms 29a,
Locking members 33a and 33b are fixed to the opposing surface of 29b in order to prevent the collimator 31 from rotating in the direction of arrow L about pins 30a and 30b, as shown in FIG. 3a. . Therefore, when the collimator 31 is supported, as shown in FIG. 3a,
The collimator 31 is supported at an angle of a small angle θ relative to the horizontal position. In addition, collimator 3
1 has an engagement notch 31a, which will be described in detail later.
31b is provided. Further, a guide 34 is provided at the bottom of the collimator support arms 29a, 29b.
a and 34b are fixed respectively, and guide the side of the detector 5 of the scintillation camera or the side of the rail of the collimator storage shelf in which various collimators are stored (not shown), and when the collimator exchange device is inserted. This is something that will happen soon.

Further, the support column 22b is provided with a driving force transmitting section 35 that generates a driving force for rotating the parallel link mechanism in the direction of arrow T by applying a rotational force to the shaft 23, and is operated by rotation of the handle 36.

Next, the driving force transmission section 35 and the collimator 31
The details of the support form of the collimator support arms 29a and 29b will be explained.

First, FIG. 4, which shows a sectional view taken from the arrow XX direction in FIG. 3a, will be used. Shaft 35 of handle 36
1 rotational axis is converted by 90 degrees by a reducer 352, and this rotational force is transmitted to a shaft 354 that fixes a gear 353. This gear 353 is configured to mesh with a gear 355 that is pivotally fixed to the shaft 23.

Further, in FIG. 3a, FIG. 5 is used which shows a cross-sectional view seen from the direction of arrow Y-Y. A threaded pin 30a passes through and is screwed into a threaded through hole 290a of the collimator support arm 29a, and a penetrating end 300a of this pin 30a engages with a recess 32a formed in the collimator 31. and supports the collimator 31. In addition, the penetrating end 300
A guide ring 301a is fixed near a to prevent the pin 30a from falling off the collimator support arm 29a. Furthermore, in order to increase the degree of freedom when attaching the collimator, the recess 32a of the collimator 31 is formed slightly larger than the through end 300a.

Note that the embodiments of the collimator exchange device are not limited to the above embodiments. For example, the collimator support arm may be U-shaped, and the lower part of the U-shape may be supported by a link mechanism. In this way, there is no need to provide a pair of link mechanisms as in the above-described embodiments, and the configuration can be simplified. Further, in the above-described embodiment, the source of driving force for rotating the parallel link mechanism is human power via the handle, but it may be controlled by an electric motor.

Next, the replacement method using the above configuration is shown in Figures 3 and 4.
This will be explained with reference to FIGS. 5 and 6.

First, a collimator 31 suitable for the purpose of diagnosis is selected from among various collimators placed on a collimator storage shelf (not shown), and supported by the pins 30a and 30b of the collimator exchange device of the present invention. Next, this collimator exchange device is transported to the detector 5 of the scintillation camera in which the detector 5 is rotated so that the detector surface is facing upward, and the supported collimator 31 is Move it so that it is nearby. And on the side of the detector 5,
Guides 34a and 34b fixed under the collimator support arms 29a and 29b, respectively, are placed along the
Move the entire device in the direction of arrow F. As a result, due to the action of the guides 34a and 34b, the arrow F
There is no need to pay attention to the deviation in the direction intersecting the direction, and it is only necessary to pay attention to the position of the collimator 31 in the direction of arrow F. The collimator 31 continues to move in the F direction until the engagement notches 31a and 31b of the collimator 31 completely engage with the protrusion P formed on the detection surface of the detector 5. FIG. 6a shows a state in which the engagement of the protrusion P is completed by the above-mentioned operation.

Next, when the handle 36 provided on the driving force transmission section 35 is rotated, the lower arms 25a and 25b of the parallel link mechanism are rotated through the reducer 352 → gear 353 → gear 355 → shaft 23, and are supported. The collimator support arms 29a and 29b then descend (state b in FIG. 6), and finally the collimator 31 is placed on the detector 5. After this, the collimator 31 is fixed to the detector 5 with screws or the like.

According to the embodiments described above, alignment between the collimator and the detector can be performed extremely easily.
That is, firstly, among the x and y components (two-dimensional) that are moved during alignment of the collimator by the guides provided under the collimator support arms,
Positioning can be performed with high accuracy without considering the one-directional component (for example, the x component). Second, the y-direction component for positioning is limited by the protrusion provided on the detector, so the operator only has to move the entire device in the y-direction. Thirdly, by supporting the collimator via a parallel link mechanism, the collimator support arms 29a and 29b always move parallel to the floor, so no matter what height the detector is located, the collimator support arms 29a, 29b always move parallel to the floor. If it is within the movable range of the arms 29a, 29b, it can be attached. Fourth
In this case, the penetrating ends of the pins that support the collimator from both sides engage with the recesses on both sides of the collimator, so that after the collimator is completely placed on the detector, it cannot be lowered further. In this case, this falling pressure is not applied to the detector.

[Effects of the Invention] According to the present invention described above, the alignment between the collimator and the detector is extremely easy and quick, and even if the collimator falls, it remains on the detector surface, so the work can be carried out safely. Because you can
This has the excellent effect that collimator replacement work can be carried out easily and safely.

[Brief explanation of the drawing]

Fig. 1 shows the detector part of a general scintillation camera, Fig. 2 a and b show a conventionally used collimator exchange cart, and Fig. 3 a and b show an embodiment of the present invention. A front view and a plan view showing an example, FIG. 4 is a cross-sectional view taken along the line X-X in FIG. 3, FIG. 5 is a cross-sectional view taken along Y-Y in FIG. 3, and FIGS. FIG. 3 is an explanatory diagram of the replacement operation. 20... Base portion, 21a, 21b... Caster, 22... Support column, 23... Axis, 25... Lower arm, 28... Upper arm, 29... Collimator support arm, 30... Pin, 34 ...Guide, 3
5... Drive force transmission section, 36... Handle.

Claims (1)

[Claims] 1 A collimator is constructed of a movable truck, a support provided on the truck, a pin that engages with a recess provided on both sides of the collimator, and a locking member that prevents the collimator from rotating around the pin. A collimator comprising: a collimator support member that removably supports the collimator; and a lifting means that raises and lowers the collimator support member with respect to a detector that is provided on the pillar and is directed upward for collimator exchange. Exchange device.