JPH01175839A - Safety device for tomograph when its table is lifted - Google Patents

Abstract

PURPOSE:To improve safety, when a table is lifted, by stopping its movement by a signal detected by an object contact detecting sensor, when the table is lifted, and moving it in a reverse direction to the moving direction of the table, immediately before it is stopped, when the table is reoperated. CONSTITUTION:An up-switch 5a is pressed, while a moving part 7 is lifted, when a man or an object comes into contact with a up-touch sensor 12a, an up self-hold relay 15 is energized opening a B contact 15b and stopping an oil pump 10 in operation, and the moving part 7 is stopped in its lifting. Simultaneously an A contact 15a closes self holding an opened condition of the B contact 15b. Here a down-switch 5b, when it is pressed, energizes an up-hold release relay, opening a B contact 17b and releasing the up self-hold relay 15 from its energization and self-hold condition, and the moving part of a table moves in a safe direction, that is, in the bottom direction. Similarly the moving part 7 lowers, when the man or the object comes into contact with a sensor 12b, the moving part 7 is stopped in its lowering. When the up switch 5a is pressed, the moving part of the table moves in the upper direction.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a safety device for lifting and lowering a table of a tomography apparatus.

(Conventional technology) Figure 4 shows a conventional fault! 1 is a configuration diagram showing a nuclear magnetic resonance diagnostic device, which is one of the LiAng devices. In Figure 4, 1
A gantry has a built-in magnet 2, etc. that generates a static magnetic field, and has a cylindrical opening 3 in its center, and 6 is a predetermined position of the gantry opening on which a subject is placed and tomography is performed. 7 is a moving part of the table; 4 is a support base that supports a cradle (not shown) of the table within the opening 3; 5 is for starting and stopping the vertical movement of the moving part of the table, etc. It is a switch panel. Each switch on the switch panel 5 is connected to a control section (not shown),
This control section is configured to operate an elevation drive section (not shown) of the moving section 7.

In the tomography apparatus having such a configuration, the operation when performing tomography will be described. First, place the subject on table 6.
When placing the down switch 5 on the switch panel 5,
b and lower the moving part 67 as shown by the dotted line in the figure.

Next, place the subject on the table 6 and switch panel 5.
Press the up switch 5a to raise the moving part 7 as shown by the solid line in the figure. In such a movement operation of the moving unit 7, as shown in the figure, the support base 4 of the gantry 1 and the table 6
The bottom of the moving part 7 is close to each other, and there is a slight gap 8a and 8b.
Create. Therefore, while the moving part 7 is moving, such a gap 8
If you get your hands or feet caught in a or 8b, there is a risk of a serious accident.

In order to avoid this danger, it is conceivable to install various touch sensors etc. in the areas where the gaps 8a and 8b are formed, and to adopt a configuration in which the control unit stops the vertical movement based on the signal from these sensors. Nothing like this has yet been developed.

On the other hand, in an automated device, when the control section inputs signals from various sensors, performs predetermined processing, and outputs control signals to the operation section, it must be equipped with a self-holding circuit to perform the predetermined processing. is well known. It is also well known that a dedicated reset switch is used to release the holding state of such a self-holding circuit.

(Problems to be Solved by the Invention) Therefore, when a table safety device is constructed using a control unit equipped with a self-holding circuit as described above and a touch sensor,
- Once an operation occurs based on the detection signal of the sensor, the moving part cannot start moving up or down unless the reset switch is operated.

That is, in order to move the table again, two steps have to be taken, making the operation complicated and troublesome, and there is a problem of lack of safety as it is easy to forget to perform the operation.

The present invention has been made in view of the above-mentioned problems, and its purpose is to provide a safety device for raising and lowering a table of a tomography apparatus, which improves the safety when raising and lowering a table without reducing its operability. It's about doing.

(Means for Solving the Problems) In order to achieve the above object, the safety device for lifting and lowering the table of the tomography apparatus of the present invention has the following configuration. That is, an object contact detection sensor is installed on the moving part of the table on which the subject is placed or at an opposite position where this moving part approaches, and a control part that generates an operation signal for raising or lowering the moving part of the table moves up and down. The up switch or down switch generates a signal that stops the table movement based on the detection signal of the sensor and maintains the table position, and upon re-operation, moves in the opposite direction to the table movement direction immediately before stopping. Release the holding by operating a switch,
It is characterized by generating a signal to move the table in a direction based on this switch operation.

(Function) When the table and an object come into contact with each other when the table is raised or lowered, the object contact detection sensor outputs an electric signal, and the control section stops the movement of the table and maintains this table position. Here, if you press the switch in the opposite direction to the table movement direction immediately before stopping, the holding state is canceled and at the same time,
The table moves in a safe direction.

(Example) Hereinafter, the present invention will be explained in detail with reference to the drawings.

FIG. 1 is a configuration diagram of a safety device for lifting and lowering a table of a tomography apparatus according to an embodiment of the present invention.

In FIG. 1, parts having the same functions as those in FIG. 4 are denoted by the same symbols, so their explanations will be omitted here. 1st
In the figure, 9 is a cylinder that is installed in the table 6 and lowers the moving part 7 from diagonally upward to diagonally downward, or vice versa, and 10 is a cylinder that sends oil into the cylinder 9 and drives the cylinder 9 with hydraulic pressure. An oil pump 11 for raising the moving part 7 is a solenoid valve installed between the cylinder 9 and the oil pump, and lowering the oil pressure in the cylinder 9 by adjusting the oil pressure between them. It is. 12a and 12b are arranged at locations that form gaps on the surface of the moving part 7 of the table 6, respectively, and detect when the moving part 7 is rising or falling into contact with an object, and output an electric signal. The down touch sensor 13 is a table control circuit that controls the drive of the moving unit 7 based on the outputs of the up switch and down switch (both not shown), touch sensors 12a, 12b, etc.

FIG. 2 is a circuit diagram showing the main parts of the configuration of the control section 13. In FIG. 2, parts having the same functions as those in FIG. 4 and FIG. 1 are denoted by the same symbols, and therefore their explanations will be omitted here. In FIG. 2, 16 is the up switch 5
Down hold release relay that is turned on and off with a, 1
7 is an up hold release relay that is turned on and off by the down switch 5b. 14 is the A contact (contact that closes when excited) of the down touch sensor 12a.
8 contacts (contacts that open when energized) 1 of the down hold release relay 16
Self-hold relay 15 is turned on by the A contact 12a of the up touch sensor and self-holds the state, and self-hold is released by the B contact 17b of the relay 17. It is a self-hold relay for use. The B contact 15b of the relay 15 is normally open, and the A contact 5a of the up switch and this B contact 1
5b are both turned on (closed), the oil pump 10 is driven. The B contact 14b of the relay 14 is also normally open, and the solenoid valve 11 is driven when both the A contact 5b of the down switch and this B contact 14b are on. 18a, 18b,
18c and 18d are terminals to which positive voltages for exciting the respective relay circuits described above are applied.

In such a configuration, the operation of the device of this embodiment is shown in FIG.
This will be explained using the flowcharts shown in FIGS. 2 and 3. First, when the up switch 5a is pressed and the moving part 7 is raised, a person or object comes into contact with the up touch sensor 12a and the contact closes, and the up self-hold relay 15 is energized. The B contact 15b opens, stopping the oil pump 10 in operation and stopping the moving part 7 from rising. At the same time, the A contact 15a closes and the B contact 15b self-holds the open state, and even if the up switch 5a is pressed, the moving part 7 does not rise. Here, when the down switch 5b is pressed, the up hold release relay is energized,
B contact 17b opens, self-hold relay 15 for up
When the excitation of is released, the B contact 15b is closed, and the self-holding state is released, the moving part of the table moves in a safe direction, that is, in a downward direction away from the object. Similarly, when the down touch sensor 12b comes into contact with a person or object while the moving part 7 is being lowered, the down self-hold relay 14 is energized, the B contact 14b opens, and the solenoid valve 10 is in operation. Close it and stop the moving part 7 from descending. At the same time, the A contact 14a closes and the B contact 1
Even if the switch 4b is held in the open state and the down switch 5b is pressed, the moving part 7 does not descend. Here, when the up switch 5a is pressed, the down bold release relay is energized, the B contact 16b opens, the B contact 14b closes, and the moving part of the table moves in a safe direction, that is, upward, away from the object. Move to.

In this way, in the device of this embodiment, the touch sensor 1
2a and 12b, the operation is stopped when a person or object touches a dangerous part of the moving part 7, so that danger can be prevented. Also, when moving the table from a stopped state,
The table can always be accurately moved in a safe direction by just one step of pressing a switch that directs the moving part of the table away from the object.

Note that the present invention is not limited to the above embodiments, and various modifications can be made within the scope of the claims.

For example, the touch sensor may be provided not on the moving part side of the table, but on the opposing position side where the table approaches, such as a part of the gantry that forms a gap with the table, or the bottom of the table.

In addition to the nuclear magnetic resonance diagnostic system M, the present invention may also be used in other tomography devices such as an X-ray CT device. Furthermore, it may be used for a horizontally movable part such as a cradle of a table.

(Effects of the Invention) As explained above, according to the safety device for lifting and lowering the table of the tomography apparatus of the present invention, the following effects can be obtained. That is, an object contact detection sensor is installed at a moving part of the table or at an opposing position where this moving part approaches, and a control part that generates an operation signal to move the moving part of the table up or down detects the sensor when going up or down. A signal is generated to stop the movement of the table and hold the table in this position, and when the table is operated again, the holding is released by operating a switch that moves in the opposite direction to the direction in which the table was moved immediately before stopping. Since a signal is generated to move the table in the direction based on this switch operation, it is possible to prevent people or objects from getting caught in the table while it is moving, and even when the table stops, it can be done in one step. Always accurately with only the operation of
In addition, since the table can be quickly moved in a safe direction, the safety when raising and lowering the table can be improved without reducing its operability. Furthermore, since a reset switch for canceling the self-hold state is not used, the configuration can be made at low cost.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram showing a safety device when lifting and lowering a table of a tomography apparatus according to an embodiment of the present invention, and FIG. 2 is a circuit diagram showing the main part of the configuration of a table control circuit according to an embodiment of the present invention. FIG. 3 is a flowchart showing the operation of an embodiment of the present invention, and FIG. 4 is a configuration diagram showing a nuclear magnetic diagnostic apparatus, which is one of conventional tomography apparatuses. DESCRIPTION OF SYMBOLS 1... Gantry, 2... Magnet, 3... Opening, 4... Support stand, 5... Switch panel, 5a
... Switch for up, 5b... Switch for down, 6... Table, 7... Moving part, 8... Gap, 9
...Cylinder, 10...Oil pump, 11...
Solenoid valve, 12a, 12b...touch sensor, 13...
・Table control circuit,

Claims (1)

[Claims] A table is moved and installed at a predetermined position in the gantry opening on which a subject is placed and tomography is performed, and an operation signal is generated to move the moving part of the table up or down based on a signal from an up switch or a down switch. In the safety device for lifting and lowering a table of a tomography apparatus, the control unit includes an object contact detection sensor installed at a moving unit of the table or an opposing position where the moving unit approaches, and the control unit controls the A detection signal from the sensor causes the table to stop moving, and a signal is generated to maintain this table position. When the table is operated again, the table moves in the opposite direction to the direction in which the table was moved immediately before stopping. A safety device for moving a table of a tomography apparatus, characterized in that it generates a signal to release the hold and move the table in a direction based on the switch operation.