Ultrasonic Single/Double Sheet Detector / Ultrasonic Paper Sensor

I. Introduction

The single/double sheet detection Sensor, also called a paper Sensor, is mainly used to detect paper, plastic, and metal films. When these materials pass through the Sensor, it can identify three states: no paper, single sheet, and multiple sheets, and output the corresponding status signal. It is mainly used in industries such as printing, papermaking, stamping, and instant noodle packet dispensing machines.

1. Product Description

Ultrasonic technology-based single/double sheet detection Sensor is mainly used to monitor multi-layer paper, plastic, and metal films in order to identify two or more thin sheets unintentionally stuck together. Each layer is compared with a stored reference value and accordingly indicated as single or double layer; the stored values can be manually corrected. It is mainly used for single-sheet pass and double-sheet alarm functions in single/double sheet detection, and is not affected by the vibration, material, or color of the inspected object. It is widely used in papermaking, stamping, instant noodle packet dispensing, and other industries.

The single/double sheet detection Sensor based on ultrasonic technology uses a specially developed ultrasonic transducer and an innovative electronic circuit. It can accurately detect double-sheet overlaps caused during the operation of a wide range of materials, including various thicknesses, transparent films, thin metal sheets, etc. This ultrasonic system is unmatched by photoelectric double-sheet detectors because it does not depend on the color of the material.

Compared with traditional mechanical or optical single/double sheet controls, the ultrasonic technology-based single/double sheet detection Sensor can adapt to various thin sheet materials without any setup. Adjustment methods such as potentiometers or probes are redundant.

2. Product Features
Includes a signal processor and two Ultrasonic Sensors (transmitter and receiver);
Reliably detects multi-layer paper, plastic board, or metal foil, sensing range 40-80mm;
Measuring material range from 20g/m2 paper to 400g/m2 card;
Measurement speed: one detection every 15ms
Ultrasonic Sensor Mounting Dimensions: M18*1.5 thread
Resolution: 3 signal types (air, single sheet, double or multiple sheets) output, enabling multiple applications.

3. Product Principle
 A high-frequency ultrasonic transmitter emits an ultrasonic beam from underneath the sheet. The sound wave causes the sheet to vibrate, which in turn generates a very small sound wave on the other side of the sheet.

 This small sound wave is received by the ultrasonic receiver. If there are two sheets, one on top of the other, the signal becomes much weaker and can barely reach the receiver.

4. Main Technical Specifications

Supply Voltage: DC 24V±15%

Operating Temperature: Probe -20～70℃, Instrument -20～60℃

Storage Temperature: -40～80℃

Working Range: 20g/m2 paper to 400g/m2 card

100g/㎡ paper to 1000g/㎡ single-layer cardboard

LED Display: shows paper status 0, 1, 2

Housing Material: Metal

Sensor: Plastic (for corrosion-resistant media, please select special materials)

High/Low Level Output:

No paper: PNP output low level 0V, NPN output high level 24V; green LED on

Single sheet: output PNP signal, normally open (PNP output high level 24V, NPN output high level 24V); yellow LED on

Double or multiple sheets: output NPN signal, normally open (NPN output low level 0V, PNP output low level 0V); red LED on

Relay output：

No paper: relay 1 normally open, relay 2 normally open

Single sheet：Relay 1 closed，relay 2 normally open

Two or more sheets：Relay 1 normally open，relay 2 closed

●Includes one signal processor and two ultrasonic sensors(transmitter and receiver)；

●Reliably detects multiple layers of paper、plastic sheets or metal foil,sensing range 40-60mm；
●Measures material range from 20g/m2 paper to 1100g/m2 card；
●The ultrasonic sensor has an M14 housing；
●Resolution:3 signal outputs(air,single sheet,double or multiple sheets)，enabling various applications。 

 The following are the specific model selections

 Model DY-ZZCG-2PN-5V:  
Analog display：
Paper absence：PNP output low level 0V, NPN output high level 5V；green light on
Single sheet：output PNP signal,normally open（PNP output high level 5V，NPN output high level 5V）；yellow light on
Double or multiple sheets: output NPN signal, normally open (NPN output low level 0V, PNP output low level 0V); red LED on
Model DY-ZZCG-2PN-24V:  
Analog display：
No paper: PNP output low level 0V, NPN output high level 24V; green LED on
Single sheet: output PNP signal, normally open (PNP output high level 24V, NPN output high level 24V); yellow LED on
Double or multiple sheets: output NPN signal, normally open (NPN output low level 0V, PNP output low level 0V); red LED on
Model DY-ZZCG-R:                   
Analog display：
No paper: relay 1 normally open, relay 2 normally open
Single sheet：Relay 1 closed，relay 2 normally open
Two or more sheets：Relay 1 normally open，relay 2 closed
Model DY-ZZCG-2PN-5V:      Model DY-ZZCG-2PN-24V:      Model DY-ZZCG-R:              

5. Installation Method

Ultrasonic single/double sheet detection sensors can be installed perpendicular to the paper. When detecting ordinary paper and film, paper sway does not affect system function.

For thin metal sheets and thicker plastic films (e.g., credit cards), it is recommended to install the system at a 27° tilt for detection.
For special types of thicker paper, the system should be installed at a 27°～30° tilt.
6. Wiring Method

DY-ZZCG-2PN-5V type:  
Blue: PNP+            White: PNP-
Green: NPN+            Yellow: NPN-
Red: 24VDC+       Black: 24VDC-
DY-ZZCG-2PN-24V type:
Blue: PNP+           White: PNP-
Green: NPN+           Yellow: NPN-
Red: 24VDC+       Black: 24VDC-
DY-ZZCG-R type:  
Relay 1:  Blue      White
Relay 2:  Green      Yellow
Red: 24VDC+       Black: 24VDC-
7. Precautions

A. The yellow wire must be reliably grounded！！！
B. The distance between the transmitter and receiver is 40mm~80mm. Precise axial alignment (±1°) is very important during installation.

If the axes of the transmitter and receiver are not aligned, working performance will be reduced.

C. Recommended installation distance: 60mm (±10mm).
D. Recommended installation angle: 27°±1°.
E. DY-ZZCG-2PN-5V type: DY-ZZCG-2PN-24V type: Ensure that the signal output wires (white, green, yellow) are not short-circuited before power-on.
F. Calibration:
When paper misdetection occurs, such as a single sheet being misdetected as a double sheet or a double sheet being misdetected as a single sheet, perform the following operations.
DY-ZZCG-2PN-5V type:
DY-ZZCG-2PN-24V type: 
1. Place a single sheet of paper between the two probes, press the right button, and release the right button after the three signal lights flash;
2. Place two sheets of paper between the two probes, press the left button, and release the left button after the three signal lights flash;
DY-ZZCG-R type:  
1. Place a single sheet of paper between the two probes, press the right button, and release the right button after the digital display flashes the number “1”;
2. Place two sheets of paper between the two probes, press the left button, and release the left button after the digital display flashes the number “2”;
G. Reset:
DY-ZZCG-2PN-5V type: DY-ZZCG-2PN-24V type: If the product is in an abnormal state, try pressing both buttons simultaneously, wait until the three signal lights flash, then release both buttons at the same time,

The product is thus reset.
DY-ZZCG-R type:  If the product is in an abnormal state, try pressing both buttons simultaneously, wait until the digital display flashes the number “0”, then release both buttons at the same time, and the product is thus reset.
H. There is no obvious air flow in the working area.

3. Comparison of common single-sheet and double-sheet detection methods

4. Application Scope

The Explore single/double sheet sensor, also known as double sheet detector, double sheet sensor, and double sheet controller, is a non-destructive testing technology. It uses ultrasonic waves for double sheet detection and is applicable to various materials including paper of various thicknesses and metal cards. It is not limited by the vibration, material, or color of the inspected object, and is widely used in printing, papermaking, stamping, instant noodle packaging machine and other industries.

Currently, the detection range for paper is divided into two types: 20g～400g and 100g～1100g.

5. Installation Instructions

This figure shows the measurement principle of the Explore ultrasonic single/double sheet sensor.

Customer usageSingle/double sheet Ultrasonic SensorDuring the process, when installing, ensure the angular correspondence between the two probes. Do not offset the opposed angle, so as to maintain the equivalence of perpendicular transmission and reception during the one-transmit one-receive process.

Fuzhou Dayu Electronics – Ultrasonic Sensor manufacturer, your considerate product consultant!

Dayu Electronics' single/double sheet Sensor is a long-established brand developed by our company over many years, with multiple models available to meet different usage effects you may want to achieve during use.

If you need more details, please call the hotline: 0591-28082552  or add enterprise QQ : 2187169532 . Fuzhou Dayu Electronics Technology Co., Ltd. will serve you wholeheartedly!