JPS6125451Y2 - - Google Patents

Description

[Detailed description of the invention] The present application displays the driving rotational speed of a dental handpiece device such as an air turbine handpiece, which changes the driving rotational speed by controlling air pressure, so that technicians can control the air pressure. The present invention relates to a rotation speed display circuit that can easily perform the following operations.

Conventionally, a supply circuit that supplies pressurized air to multiple dental handpieces with built-in air turbines includes:
A foot controller for varying the supply pressure of pressurized air to vary the rotational speed of the air turbine is commonly provided. Generally, this type of handpiece is capable of rotating an air turbine up to a maximum of about 500,000 rpm, and is variably adjusted to reduce the rotation speed depending on the treatment mode. Approximately 100,000 yen, especially for medium cutting performed during root canal treatment.
Adjusted to rpm. The air turbine rotation speed is normally adjusted by the degree of foot pressure applied to a foot controller placed on the floor, but fine adjustment of the air turbine rotation speed by the foot pressure is It is extremely difficult to maintain a constant intermediate rotation speed, such as 100,000 rpm, especially by foot pedal operation. Furthermore, whether or not the desired number of rotations is actually obtained by the foot operation depends solely on the operator's intuition, which has the disadvantage that the degree of cutting or polishing of the teeth may be excessive or insufficient.

Therefore, in order to improve such defects, the present application equips a dental handpiece device with a display circuit that displays changes in rotation speed due to adjustment of air pressure.
The device is constructed so that the technician can easily control the air pressure.The example will be described in detail below with reference to the drawings. 1a and 1b are equipped with different types of cutting or polishing bars, and are used for the purpose of treatment work. Each of the handpieces has a built-in air turbine, and hanger switches 2a and 2b are connected to each of the handpieces 1a and 1b. The hanger switches 2a and 2b are comprised of valve mechanisms that are closed when the handpiece is latched to the hanger device and open when the latching is released, and their input ends are connected to the pressurized air source 3, respectively. For example, the air pressure is set to 2.2, which is necessary for the air turbine to reach 500,000 rpm, by controlling the air pressure controller 4 and the pedal pressure.
Switching valve 5 that alternately switches between Kg/cm ² and 0.2 Kg/cm ² necessary for the air turbine to reach 100,000 rpm.
The pressurized air supply circuit 6 is connected to the pressurized air supply circuit 6. Reference numeral 7 denotes a handpiece used for other treatment operations, which has an electric micromotor built therein, and is connected to a pressurized air circuit 8 for air cooling and a current supply circuit 9. This handpiece 7
A hanger switch 10 similar to the above is connected to the pressurized air circuit 8, and a foot controller 1 is connected to the input end of the hanger switch 10, which is normally closed and can be opened by stepping on the foot.
The pressurized air source 3 is connected via 1.
Further, the current supply circuit 9 of the micromotor handpiece 7 is connected to a rotation speed display circuit 12 which is varied depending on the degree of depression of the foot pedal 11' of the foot controller 11. Reference numeral 13 denotes a display circuit which is made up of an electronic circuit and displays the number of revolutions in analog or digital form, and its power supply circuit 14 includes air operated by pressurized air provided corresponding to each of the handpieces 1a, 1b and 7, respectively. Actuation switches 15a, 15b, and 16 are connected in parallel. The rotation speed display circuit 13 also includes a circuit in which a fixed resistor 17 and a variable resistor 18 are connected in series.
A relay contact 1 that individually shorts the fixed resistor 17
9' and a normally closed short-circuit switch 20 are connected to each other. The variable resistor 15 is mutually variable in relation to the degree of depression of the foot pedal 4' of the foot controller 4 and the foot pedal 11' of the foot controller 11, and the relay contact 19' is pedal 1
The short-circuit switch 20 is closed by the relay 19 activated when the foot 1' is pressed, and the short-circuit switch 20 is opened when the changeover valve 5 is switched to the low pressure side of, for example, 0.2 kg/cm ² .

For example, when the first handpiece 1a is removed from its hanger device, the hanger switch 2a is opened and pressurized air can be supplied, and the selector valve 5 now controls the rotational speed of the air turbine to about 50.
Assuming that the air pressure is 2.2 kg/cm ² , which is the air pressure required to reach 10,000 rpm, the pressure has been switched to the high pressure side, and when the foot controller 4 is pressed in this state, pressurized air is supplied only to the first hand piece 1a. It can rotate up to 500,000 rpm depending on the degree of pedal pressure. On the other hand, the air-operated switch 15a corresponding to the first handpiece 1a is turned ON, and the power source 14 is applied to the rotation speed display circuit 13, and the fixed resistor 17 of the voltage variable circuit 21 is short-circuited by the short-circuit switch 20. The voltage of the voltage variable circuit 21 changes in proportion to the variable resistor 18, which varies in accordance with the degree of pedal pressure of the foot controller 4, and therefore changes the rotation speed corresponding to the voltage change of the voltage variable circuit 21. The display circuit 13 will display the information. In the above, if the switching valve 5 changes the rotational speed of the air turbine to approximately
Assuming that the air pressure is changed to the low pressure side of 0.2 kg/cm ² required for 100,000 rpm, the short circuit switch 20 in the voltage variable circuit 21 is turned OFF.
Therefore, the voltage of the variable voltage circuit 21 of the fixed resistor 17 drops, and therefore the rotation speed display circuit 13 displays the rotation speed up to about 100,000 rpm. This effect is exactly the same even when the second handpiece 1b is removed from its hanger device.

Next, when the third handpiece, that is, the micromotor handpiece 7, is removed from its hanger device, the corresponding hanger switch 10 is opened and pressurized air can be supplied. When the hand controller 11 is pressed, the air is guided to the pressurized air circuit 8 to cool the inside of the hand piece, and a drive voltage is applied to the energizing circuit 9 via the rotation speed adjustment circuit 12, causing the micromotor to rotate. The rotation of this micromotor is caused by the pressure pedal 1 of the foot controller 11.
It is variably adjusted by the degree of pedal pressure of 1', and
When the pedal 11' is depressed, the relay 19 is activated and its relay contact 19' is closed, thereby short-circuiting the fixed resistor 17 of the variable voltage circuit 21. On the other hand, the number of revolutions of the micromotor is varied depending on the degree of depression of the pedal 11', and at the same time, the variable resistor 18 is also varied in proportion to this, so the number of revolutions display circuit 13 displays the number of revolutions of the micromotor. It turns out.

As described above, according to the present application, the technician can easily know the number of rotations of the dental handpiece, so that dental treatment can be performed safely and accurately, and the configuration is simple. It has the following advantages.

[Brief explanation of the drawing]

The drawing is a circuit diagram showing an embodiment of the present application. In the figure, 1a, 1b, 7 are handpieces, 2a, 2
b, 10 is a hanger switch, 3 is a pressure supply source,
4 and 11 are foot controllers, 5 is a switching valve, 1
3 is a rotation speed display circuit, 14 is its power supply circuit, 15
a, 15b, 16 are air operated switches, 17 is a fixed resistor, 18 is a variable resistor, 20 is a short circuit switch,
21 is a voltage variable circuit.

Claims (1)

[Scope of utility model registration request] In a dental handpiece device that is driven by pressurized air and whose driving rotational speed is varied by adjusting the air pressure according to the degree of depression of a foot controller, a rotational speed display circuit that displays the driving rotational speed of the device is provided. , a power supply circuit that is opened and closed by an air-operated switch operated by the pressurized air, and a voltage variable circuit that controls the input voltage by a variable resistor that is varied in accordance with the degree of depression of the foot controller. A rotation speed display circuit in a dental handpiece device, characterized by comprising: