Classifications

• • H—ELECTRICITY
  • H03—ELECTRONIC CIRCUITRY
  • H03K—PULSE TECHNIQUE
  • H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
  • H03K17/94—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the way in which the control signals are generated
  • H03K17/945—Proximity switches
  • H03K17/95—Proximity switches using a magnetic detector
  • H03K17/952—Proximity switches using a magnetic detector using inductive coils
  • H03K17/953—Proximity switches using a magnetic detector using inductive coils forming part of an oscillator
  • H03K17/9532—Proximity switches using a magnetic detector using inductive coils forming part of an oscillator with variable frequency
• • H—ELECTRICITY
  • H03—ELECTRONIC CIRCUITRY
  • H03K—PULSE TECHNIQUE
  • H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
  • H03K17/94—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the way in which the control signals are generated
  • H03K17/945—Proximity switches
  • H03K17/95—Proximity switches using a magnetic detector
  • H03K17/9505—Constructional details
• • H—ELECTRICITY
  • H03—ELECTRONIC CIRCUITRY
  • H03K—PULSE TECHNIQUE
  • H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
  • H03K17/94—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the way in which the control signals are generated
  • H03K17/945—Proximity switches
  • H03K17/95—Proximity switches using a magnetic detector
  • H03K17/952—Proximity switches using a magnetic detector using inductive coils
  • H03K2017/9527—Details of coils in the emitter or receiver; Magnetic detector comprising emitting and receiving coils
• • H—ELECTRICITY
  • H03—ELECTRONIC CIRCUITRY
  • H03K—PULSE TECHNIQUE
  • H03K2217/00—Indexing scheme related to electronic switching or gating, i.e. not by contact-making or -breaking covered by H03K17/00
  • H03K2217/94—Indexing scheme related to electronic switching or gating, i.e. not by contact-making or -breaking covered by H03K17/00 characterised by the way in which the control signal is generated
  • H03K2217/945—Proximity switches
  • H03K2217/95—Proximity switches using a magnetic detector

Definitions

• the invention relates to a non-contact inductive proximity switch with a pre-damping element according to the preamble of claim 1.
• Non-contact proximity switches are used as electronic switching devices, especially in automation technology. They have long been known and u. a. also produced and sold by the applicant.
• Inductive proximity switches detect an electrically conductive, preferably metallic target in a monitoring area. They have at least one sensor coil and can be operated with current pulses or with continuous, usually sinusoidal alternating current. The coil can be part of an oscillator and determine its frequency. The transmitter coil can also be powered by a generator with pulsed or sinusoidal current. The sensor can also be used as a transformer, z. B. be constructed as a differential transformer and thus have more transmitting or receiving coils.
• the attenuation is evaluated, ie. H. the change of the inductance and / or the impedance of a coil, or the coupling factor between two or more coils.
• a control unit generates upon reaching or falling below a threshold, a preferably binary switching signal.
• sensor coils are used as planar coils, i. H. designed as printed conductors in the well-known printed circuit board technology.
• DE 10 2006 053 222 A1 shows an inductive proximity switch with a ring screen arranged on the printed circuit board, which cooperates with the coils such that the switching distance, or the directional characteristic of the proximity switch, remains essentially uninfluenced by the installation position.
• DE 100 66 293 B4 shows an inductive proximity switch with a circuit board coil and a short circuit winding arranged on the same circuit board, which is interrupted at one point, and can be tuned with a resistor bridging this interruption.
• resistor can be tuned only once during production with the device open, which also carries the risk of contamination when removing resistance material.
• the object of the invention is to provide an inductive proximity switch, the o. G. Disadvantages does not have, is inexpensive to produce, and is equally flush as not flush mountable. Being flush means that it can be installed in metal up to its active surface, and not flush, that it must not be damped in the area of its active surface by a metallic environment.
• the ring structure is interrupted at least one point and electrically connected to a preferably variable Abstimmwiderstand, but also a
• Fixed resistor can be switched clocked.
• the pre-damping element is thus not only switchable, but also designed tunable.
• the installation (operating state) should be manually and / or automatically adjustable in metallic or non-metallic environment.
• the circuit according to the invention can be used in inductive proximity switch with conductive and non-conductive front surface.
• the proximity switch can be installed in a conductive or in a non-conductive environment, and manually adapted to its installation environment, or recognize its surroundings itself and turn on the Vorbedämpfungselement automatically on or off. The invention will be explained in more detail with reference to the drawing.
• Fig. 1 shows a proximity switch according to the invention as a three-wire device.
• Fig. 2 shows the Vorabsämpfungselement invention in perspective.
• 3 and 4 show further embodiments of the pre-damping element.
• Fig. 1 shows the essential components of the inductive proximity switch.
• the sensor coil 1 forms with the capacitor C a resonant circuit which is fed by an oscillator circuit 4 acting as a negative resistance, d. H. is attenuated.
• Shown is a current mirror circuit that does not require Spulenanzapfung and in the lower current mirror a Ab Disabilityberichtkeit by a resistor RA, here an electronic potentiometer 7, offers.
• the upper current mirror is used for feedback. Further details are disclosed in DE 196 50 793 C1.
• the oscillator circuit 4 and an evaluation circuit 5 are housed together in a custom circuit (ASIC), without limiting the invention thereto.
• the ASIC 8 also contains a control module with the illustrated threshold switch (trigger) and a logic device, eg. B. a microcontroller.
• the evaluation circuit 5 controls the oscillator circuit 4, here their amplitude with the electronic potentiometer 7 or a resistance matrix, not shown.
• the amplitude falls in the presence of a target (switching flag) in the monitoring area, which leads to the generation of a binary switching signal when falling below a predetermined switching threshold.
• the switching signal is output via the P-switching switch 9.
• the switch 9 may also be N-switching or antivalent.
• light signals can be generated with the aid of LEDs of different colors, which output the switching state, an error, or another signal.
• the pre-damping element 2 is housed together with at least one sensor coil 1 as a conductor in or on a printed circuit board 3. For a better overview, an exploded view with only one sensor coil 1 was selected.
• the pre-damping element 2 is interrupted in two places and with
• Abstimmwiderboxn 6 connected, which can be switched on by the ASIC 8 or shorted. You could also be controlled by analogy.
• 2 shows a pre-damping element according to the invention in a perspective exploded view.
• the sensor coils 1 form a differential transformer, wherein the normally arranged in the middle between the sensor coils 1 transmitter coil has been omitted for clarity, as well as the connections for the sensor coils 1.
• the pre-damping element 2 extends over a plurality of layers of the printed circuit board 3 shown in FIG. 1 and has two discontinuous rings provided with contacts.
• the electrical connections can be performed as a via over several layers of the printed circuit board 3. They serve to tune the impedance. They can be connected to the device ground, a tuning resistor 6 and / or the ASIC 8, as well as among each other.
• FIGS. 3 and 4 show further exemplary embodiments of the pre-damping element 2 according to the invention in plan view, wherein the illustration of the electrical connections has been dispensed with.
• the inventive inductive proximity switch is suitable depending on the wiring of the pre-damping element 2 in a first mode for installation in a metallic environment and in a second mode for installation in a non-metallic environment.

Landscapes

• Switches That Are Operated By Magnetic Or Electric Fields (AREA)
• Electronic Switches (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=57068057

Family Applications (1)

Country Status (4)

Families Citing this family (2)

Citations (2)

Family Cites Families (16)

• 2015
  • 2015-09-24 DE DE102015218340.8A patent/DE102015218340B4/de active Active
• 2016
  • 2016-09-21 CN CN201680054329.3A patent/CN108028649B/zh active Active
  • 2016-09-21 WO PCT/EP2016/072339 patent/WO2017050786A1/de unknown
  • 2016-09-21 EP EP16775532.1A patent/EP3311488A1/de not_active Withdrawn

Patent Citations (2)

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events