Device for curing with light

• US 6,095,812 A
• Filed: 03/01/1999
• Issued: 08/01/2000
• Est. Priority Date: 03/11/1998
• Status: Expired due to Fees

• Current Assignee: Ivoclar AG
• Original Assignee: Ivoclar AG
• Inventors: Rohner, Gottfried, Senn, Bruno, Fritsche, Gregor
• Primary Examiner(s): Lucchesi, Nicholas D.
• Application Number:
  US09/260,318
• Time in Patent Office: 519 Days
• Field of Search: 433/28, 433/29, 362/183, 362/804
• US Class Current: 433/29
• CPC Class Codes: A61C 19/004 Hand-held apparatus, e.g. guns
• CPC Class Codes: H05B 39/044 continuously H05B39/042 takes precedence
• CPC Class Codes: Y02B 20/00 Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps

Abstract

A curing device for curing dental materials by light-induced polymerization has a supply station and a hand-held apparatus including a light source. A detachable cable connects the hand-held apparatus to the supply station. An output control device controls the light source in order to ensure a uniform light intensity, wherein the output control device has a preset nominal output. The output control device includes a control FET. The cable is connected within the output control device. The output control device prevents switching on the curing device or emits a warning signal when the nominal output requires a voltage, surpassing a control bias voltage minus a potential difference of the control FET, or a corresponding current.

Claims

1. A curing device for curing dental materials by light-induced polymerization, said curing device comprising:

a supply station;

a hand-held apparatus comprising a light source;

a detachable cable connecting said hand-held apparatus to said supply station; and

an output control device controlling said light source in order to ensure a uniform light intensity, wherein the output control device has a preset nominal output, the output control device comprising a control FET;

said cable connected within said output control device, wherein said output control device prevents switching on of the curing device, or emits a warning signal, when said nominal output requires a voltage, surpassing a control bias voltage minus a potential difference of said control FET, or a corresponding current.

2. A curing device according to claim 1, wherein:

said cable comprises a control line;

said output control device comprises a voltage sensor for detecting a terminal voltage of said light source and producing a terminal voltage signal;

said output control device further comprises a current sensor for detecting a current of said light source and producing a current signal;

said output control device further comprises an evaluation circuit;

said terminal voltage signal and said current signal supplied via said evaluation circuit to said control line of said cable.

3. A curing device according to claim 2, wherein:

said cable comprises a control line;

said supply station comprises a control circuit embodied as a switch control for controlling said control FET;

said control circuit connected to said control line.

4. A curing device according to claim 3, wherein said control circuit has a control characteristic line for linearly increasing with increasing control voltage an output voltage beginning at a soft start value, wherein the output voltage is supplied through said cable to said light source.

5. A curing device according to claim 4, wherein a slope of a control function of said control circuit for controlling said control FET is slightly greater than 1.

6. A curing device according to claim 2, wherein said hand-held apparatus comprises a calibrating unit for calibrating said current sensor, said voltage sensor, and said evaluation circuit.

7. A curing device according to claim 6, wherein said evaluation circuit comprises a dc/ac converter calibrated by said calibrating unit.

8. A curing device according to claim 6, wherein said calibrating unit during calibration evaluates all components of said hand-held apparatus that exhibit tolerances, wherein said calibrating unit comprises a memory and wherein calibrating data are stored in said memory, wherein said hand-held apparatus is calibratable independent of a length of said cable.

9. A curing device according to claim 8, wherein said memory is an EEPROM.

10. A curing device according to claim 2, wherein said hand-held apparatus has a start/stop switch connected to said evaluation circuit, wherein said start/stop switch has a keying function and, when actuated, delivers a soft start signal to a control line.

11. A curing device according to claim 2, wherein said output control device compensates for different lengths of said cable.

12. A curing device according to claim 2, wherein said hand-held apparatus comprises a fan and auxiliary devices, wherein said control FET supplies a controlled output voltage to said cable, and wherein said fan and said auxiliary devices are supplied via said cable with an auxiliary output voltage that is independent of said controlled output voltage.

13. A curing device according to claim 12, wherein said evaluation circuit has an output terminal for said fan for activating said fan, wherein an activation period of said fan for cooling said light source is determined by said evaluation circuit based on continuous or accumulated period of use of said light source.

14. A curing device according to claim 2, wherein said evaluation circuit comprises a signaling device for indicating that a lamp of said light source must be exchanged when an inner resistance of said light source is outside of a threshold value.

15. A curing device according to claim 14, wherein said threshold value is a controlled output voltage defined as said control bias voltage plus a minimum potential difference of said control FET.