KR101535271B1 - Electric feeder of homing method using a magnetic field - Google Patents

Abstract

The present invention relates to an electric feeder of a homing method using a magnetic field and, particularly, to the electric feeder of the homing method using the magnetic field which can correct transportation position by detecting an absolute position of a transportation unit for transporting a carrier tape. The electric feeder for transporting the carrier tape where a component is accommodated includes: a sprocket (12) which is driven by a motor to transport the carrier tape; a storage medium which stores an index of the absolute position of each tooth of the sprocket (12) and a correction value between homing positions from each index; a magnetic field generation unit (122) which generates a different magnetic field as to each tooth; and a magnetic sensor (111) for detecting the magnetic field generated in the magnetic field generation unit (122).

Description

TECHNICAL FIELD [0001] The present invention relates to an electric feeder of a homing type using a magnetic field,

The present invention relates to an electric feeder of a homing type using a magnetic field and more specifically to an electric feeder of a homing type using a magnetic field for detecting an absolute position of a feeding means for feeding a carrier tape and correcting a feeding position .

The electronic component or label may be transferred to a position that is continuously determined by the tape serving as the base substrate. The transferred electronic component or label may then be placed or attached to the device or module by a pick-up device.

A device that picks up a plurality of electronic components and mounts them on a predetermined position of a printed circuit board (PCB) is called a surface mounting device (SMD). A carrier tape supply device or a feeder for feeding a carrier tape may be used for supplying parts to a printed circuit board in a surface mount device. Various types of feeders are known in the art and generally include an input module for input of a carrier tape having parts, a component exposure module for separating the cover tape from the inserted carrier tape and exposing the components, and a separate cover tape and empty pockets And a discharge module for discharging the base tape.

The tape containing the electronic component can be transported by the roller or the sprocket and the transport of the tape needs to be controlled so that the electronic component can be picked up at a predetermined position.

As a prior art relating to the supply of carrier tapes, Patent Document No. 2002-0047860 entitled " Tape Feeder for Component Mounting Apparatus " The prior art includes a frame; A carrier tape conveying means provided rotatably on one side of the frame and having a sprocket for intermittently conveying the carrier tape; A top cover discharging means provided on the other side of the frame for discharging a top cover which is peeled off from the carrier tape, the top cover discharging means having a pair of discharging gears with a top cover sandwiched therebetween; And a drive means for simultaneously driving at least one of the pair of discharge gears. The carrier tape transporting means further includes reverse rotation preventing means for preventing reverse rotation of the sprocket And the driving means includes a transfer worm hole coaxially disposed with the sprocket, a transfer worm gear engaged with the transfer worm hole, and a second worm gear cooperating with the first roller coaxially installed on one side of the discharge gear, A discharge wormhole coaxially installed with the second roller, a discharge worm gear engaged with the discharge wormhole, and a drive motor for driving the transfer worm gear and the discharge worm gear at the same time And a tape feeder for a component mounting machine. And rotation angle sensing means for sensing a rotation angle of the sprocket rotated by the driving means.

Another prior art related to the supply of a carrier tape is disclosed in Patent Registration No. 1232134 'A tape feeder for quickly detecting the position of a blank part and discharging the carrier tape'. The prior art includes a tape loading portion to which a carrier tape is loaded, a drive sprocket that is sequentially disposed along a conveyance path of the carrier tape for conveying the carrier tape supplied from the tape loading portion, A component pickup portion for exposing the component so that the component can be picked up from the carrier tape transported by the driving portion, a sensing portion for sensing the component or the transport hole of the carrier tape, and a component And a control section for controlling the rotation of the first drive sprocket and / or the second drive sprocket so that the carrier tape passes through the part pickup section at a speed higher than the feed speed necessary for picking up the component when the monitoring signal is inputted Detects the position and inserts the carrier tape. As it disclosed with respect to the tape feeder to discharge.

Prior art or known tape transport devices disclose techniques for detecting the position of a sprocket to detect the transport position of the tape or for detecting the presence of a component to adjust the tape transport speed. However, it does not disclose a technology for accurately detecting the transfer position of the tape and accordingly controlling the rotation level of the drive motor. For example, a device such as a sprocket for transporting a tape may be engaged with a device such as a gear and a transfer error may occur between rotation of the sprocket and other power transmission means due to processing errors or backlash. Such an error may cause accumulation of the transfer error of the tape, and the component may not be accurately transferred to the pickup position by simply controlling the rotation angle of the drive motor. The prior art does not disclose a method that can compensate for such transport errors that may occur during the transport of the tape.

The present invention has been made to solve the problems of the prior art and has the following purpose.

An object of the present invention is to provide an electric feeder of a homing type using a magnetic field which detects the absolute position of a tape transporting means such as a sprocket and controls the transporting position and the homing position of the carrier tape to be the same at any operating point.

According to a preferred embodiment of the present invention, an electric feeder for transporting a carrier tape in which a component is accommodated is sprocket driven by a motor for transporting the carrier tape; An index of an absolute position of each tooth of the sprocket and a correction value between each index and a homing position are stored; A magnetism generating unit for generating magnetic fields different from each other; And a magnetic sensor for detecting a magnetic field generated in the self-generating unit.

According to another preferred embodiment of the present invention, there is further provided a rotation detection sensor for detecting the rotation of the sprocket.

According to another preferred embodiment of the present invention, the magnetism generating unit is arranged along the circumferential surface of the sprocket so as to generate at least one magnetic field different from each other at different positions.

According to another preferred embodiment of the present invention, a method for correcting the homing position of a carrier tape on which a component is received comprises the steps of: storing an index of the absolute position of each tooth of the sprocket carrying the carrier tape; Storing a correction value between the indexed tooth and a homing position;

Reading the absolute position of the tooth by a magnetic sensor; And synchronizing the sprocket to the rotor position of the motor driving the sprocket.

According to another preferred embodiment of the present invention, said synchronization is achieved by detecting rotation of the sprocket.

The feeder according to the present invention determines the absolute position of the sprocket and applies an intrinsic correction value according to the pre-stored position of the sprocket in the storage medium such as the non-volatile memory, The conveying position of the carrier tape can be repetitively made constant so that the component can be transferred to the predetermined pickup position. The feeder according to the present invention can determine the absolute position of the sprocket when the first power is turned on and the homing drive is performed so that a homing structure in which the transport position and the homing position of the carrier tape are the same can be provided even if the sprocket is positioned at any tooth Effect.

FIG. 1A shows an embodiment in which the position of a sprocket applied to a feeder according to the present invention is detected.
Fig. 1B shows an embodiment of a sprocket applied to a feeder according to the present invention.
2 shows an embodiment of an electric feeder according to the present invention.
3 is a block diagram schematically illustrating an embodiment of a position correction method according to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the embodiments shown in the accompanying drawings, but the present invention is not limited thereto. In the following description, components having the same reference numerals in different drawings have similar functions, so that they will not be described repeatedly unless necessary for an understanding of the invention, and the known components will be briefly described or omitted. However, It should not be understood as being excluded from the embodiment of Fig.

In the following, the present invention will be described by showing an embodiment of a carrier tape supply device for transferring a carrier tape accommodated with an electronic component to a pickup position. However, a detection sensor according to the present invention can be applied to detect the transporting position of the tape for transporting various kinds of parts or labels, and the present invention is not limited to the embodiments shown. The tape can be continuously transported and the transport distance can be controlled. For example, a transfer hole may be formed in the tape and the transfer hole may be engaged with the teeth of the rotation transfer means such as a sprocket. The horizontal traversing distance between the teeth is predetermined and the rotation of the conveying means can be controlled by a driving means such as, for example, a BLDC motor. The position of the tape currently engaged with the transport means can be sensed and the current position of the tape can be detected. The distance between the pickup position and the current position of the component or label is determined and the tape can be positioned at the predetermined pickup position by the operation control of the drive means. And parts or labels can be picked up. The transfer of the tape by the transfer means is set so that the part or label is positioned at the pick-up position.

During the transfer of the carrier tape, a homing command can be made with the initial power applied. Even if the position of the carrier tape is set to a predetermined position in accordance with the homing command, the homing drive is completed according to the tooth position of the sprocket positioned at the end of the power source, and an error may be generated. Such an error can be caused by various causes such as, for example, machining errors of the teeth, eccentricity of the sprocket, or backlash.

According to the present invention, irrespective of the position of the teeth of the sprocket when the homing drive is completed, the deviation between the repetition degree of the homing drive completion time and the position after the supply of the carrier tape, for example, .

According to the present invention, an absolute address index can be given to the teeth of the sprocket in order to reduce the deviation of the positions stopped in the respective feeding processes of the carrier tape. For example, each tooth of a sprocket with 40 teeth can be given the following index, and each index can be distinguished by an analog to digital converter.

TOUCH INDEX One 2 3 ‥‥‥ 40 Magnetic force (ADC) 0.0 to 26 27 ~ 51 52 ~ 77 ‥‥‥ 998-1023 Absolute angle 0 9˚ 18˚ ‥‥‥ 351˚

The absolute address index of the sprocket teeth is increased in the N + 1 manner, and the absolute address index is increased by the number of teeth and again begins at 1. The magnetic force means the magnitude of the magnetic field which can be generated by the tooth having the index, respectively, and different magnetic force values can be generated for different indices. This allows teeth or indexes to be identified by detecting magnetic field or magnetic force values. And the index for each tooth of the sprocket and hence the magnetic force can be stored in a storage medium such as, for example, a non-volatile memory. And can be called by the control unit to supply the carrier tape.

An embodiment of a sprocket having such an index will be described below.

FIG. 1A shows an embodiment in which the position of a sprocket applied to a feeder according to the present invention is detected, and FIG. 1B shows an embodiment of a sprocket applied to a feeder according to the present invention.

1A and 1B, an electric feeder for transporting a carrier tape accommodating a component according to the present invention includes a sprocket 12 driven by a motor for transporting the carrier tape; An index of an absolute position of each tooth of the sprocket 12 and a correction value between respective indexes and a homing position are stored; A self-generating unit (122) generating a magnetic field different for each of the teeth; And a magnetic sensor 111 for detecting a magnetic field generated in the self-generating unit 122. [

The tape may be composed of, for example, a base tape having pockets in which the electronic components are received and a cover tape attached to the top of the base tape to protect the electronic components. The tape can be transported by the sprocket 12 driven by the motor and the transport hole can be formed in the tape for transport by the sprocket 12. [ The teeth of the sprocket 12 can be engaged with the transfer hole of the tape and the transfer distance of the tape can be calculated by measuring the rotation angle of the sprocket 12. [

The tape can be conveyed through a tape guide 13 corresponding to a feeding device or a conveying device, and the sprocket 12 can form a part of the feeding device. The tape guide 13 includes a separation start portion 131 in which the separation of the cover tape is started, a separation inducing portion 132 in which the cover tape starts to separate, and an electronic part accommodated in the pocket of the base tape by separation of the cover tape, And a pickup part 133 for picking up the electronic parts.

The tape can be transported to the pickup portion 133 by the sprocket 12 and the transporting means 12 can be rotated by the drive motor 14. [ The drive motor 14 may be, for example, but not limited to, a BLDC (blushless DC) motor.

The rotation of the drive motor 12 can be controlled by the control module and the rotation angle of the transfer means 12 can be controlled by the rotation control of the drive motor 12 so that the transfer distance of the tape can be adjusted accordingly. If the mechanical error or the operation error is not generated, the rotation angle of the motor coincides with the rotation angle of the transfer means 12, and the transfer distance of the tape is accurately calculated, and the electronic part accommodated in the base tape is accurately positioned in the pick- Can be controlled. Mechanical errors include, for example, the backlash of gears, machining errors, shaft errors, or any misalignment that occurs during the manufacturing or connection of different parts or machines, such as misalignment of the transfer hole and teeth. And the operating error includes the operating time and the calculation error during the operation of the machine. Such an error can be generated in different sizes according to the respective teeth of the sprocket 12, whereby power is supplied to the sprocket 12 and the position corresponding to the homing command according to the teeth at which the sprocket 12 starts to feed, An error may occur in the transport distance up to < RTI ID = 0.0 > In this specification, a homing position means a predetermined position to be conveyed by a homing command while the feeding is started, and for example, a pickup position of the component can be a homing position.

The component may not reach the correct pickup position due to an error in the homing position at the time when the homing command is driven and the corresponding tooth of the sprocket 12 corresponding thereto. Therefore, such an error needs to be corrected. To this end, according to the present invention, an index is given to the teeth of each sprocket 12 and the error value can be stored accordingly.

According to the present invention, the index of the sprocket 12 can be detected by the magnetic sensor 111 and the position of the sprocket 12 can be detected by the rotation detection sensor 112. The magnetic sensor 111 may be a detection means capable of detecting a magnetic field or a magnetic force generated from each tooth, and may be, for example, a gauss meter or a Hall sensor. The specific teeth of the sprocket 12 can be detected by the magnetic sensor 111. [ The rotation detection sensor 112 is capable of detecting the rotation of the sprocket 12 and detecting the angular speed of the sprocket 12, for example. The rotation detection sensor 112 may be used to synchronize the sprocket 12 with respect to rotation of the motor. The rotation detection sensor 112 may be any means capable of detecting rotation of the sprocket 12 and may be, for example, a photosensor.

According to the present invention, the position of a specific tooth of the sprocket 12 can be determined by the magnetic sensor 111. And the sprocket 12 teeth according to the commencement of the homing command for the component transfer to the homing position can be determined. And the component can be transferred by being corrected by a predetermined correction value stored. The sprocket 12 includes a shaft connecting portion 121, a magnetism generating unit 122 forming a concentric circle with the shaft connecting portion 121, a reference pitch unit 123 formed along the circumferential surface of the magnetism generating unit 122, And an engaging unit 124 serving as a direct means for moving the engaging unit 124. [ The axis connection portion 121 may have a hole shape that can be coupled to a shaft fixed to the frame and the magnetism generating unit 122 may have a circular shape having a different magnetic field at different angles from the center with respect to the reference position, It can be a magnet. The self-generating unit 122 is a means for generating different magnetic forces for teeth having different indices. The magnetic force generating means 122 may be a means capable of generating a plurality of magnetic forces with respect to one index and capable of generating any magnetic field or magnetic force capable of distinguishing according to each index, if necessary. The reference pitch unit 123 may be a tooth formed along the circumference, for example, formed to correspond to the pitch or unit transfer angle of the engaging unit 124, and the engaging unit 124 may be formed along the circumference engaging the transfer hole It can be a tooth formed at the same pitch. The reference pitch unit 123 can be a tooth formed along the circumferential direction at the same pitch as the engaging unit 124 and each tooth can be detected to be rotated by the rotation detection sensor 112. [ Depending on the power transmission structure, the sprocket 12 may have a connecting unit 124a connected to a power transmitting means 14 which is connected to a driving motor such as a gear.

According to the invention, the sprocket (12) has a plurality of successive pitches for conveying the tape, each of the plurality of pitches being detected by a magnetic sensor (111) and having an error for each of the plurality of pitches Can be predetermined and stored according to the index.

When the sprocket 12 is rotated, the magnetism generating unit 122 is rotated at the same rotational speed as the sprocket 12 and the magnetic sensor 111 provided at the fixed position passes through the fixed position of the magnetism generating unit 122 Can be detected. The magnetism generating unit 122 may be a circular magnet and have different magnetic fields at different positions and the magnetic sensor 122 may detect that a specific position of the transfer unit 12 passes through a predetermined point by detecting a magnetic field It can detect. In other words, certain teeth can be detected. With the rotation of the sprocket 12, the reference pitch unit 123 is rotated at the same rotational speed as the self-generating unit 122, and the rotation of the specific tooth can be detected by the rotation detection sensor 112. In this way, a predetermined portion of the sprocket 12 is detected by the magnetic sensor 111. The position of the magnetic sensor 111 and the rotation detection sensor 112 are fixed in advance and the absolute position of the sprocket 12 can be detected by measuring the magnetic field or magnetic force at the fixed position. And the transport distance is determined and the carrier tape can be transported by the sprocket 12 to the homing position in accordance with the homing drive. The sprocket 12 can be rotated by engaging drive means such as, for example, a BLDC motor, with the linking unit 124a. The rotational angle of the drive means is predetermined or measurable and the rotational angle of the sprocket 12 can be determined according to the rotational angle of the drive means.

The magnetic sensor 111 and the rotation detection sensor 112 can be attached to a detection board having a circuit board structure and the detection board can be fixed to a fixing means 113 such as a bracket fixed to a feeder or a frame of the transfer device, As shown in FIG. The position of the detection board is fixed and the magnetic sensor 111 and the rotation detection sensor 112 respectively detect that a specific part of the self generating unit 122 and the reference pitch unit 123 is the magnetic sensor 111 and the rotation detection sensor 112 ≪ / RTI > The detection board transmits the value detected by the magnetic sensor 111 and the rotation detection sensor 112 to the control unit and the control unit synchronizes with the drive means based on the detected value and starts homing according to the predetermined correction value do. This allows the part to be accurately positioned at the pick-up position regardless of the teeth of the sprocket 12 at the start of homing. The detection board or securing means 113 may have any structure known in the art and the invention is not limited to the embodiments shown.

An embodiment in which the detection sensor according to the present invention is applied will be described below.

Referring to FIG. 2, the carrier tape accommodating the electronic parts may be inserted through the insertion module 201 and transferred to the tape guide 203 via the transfer module 202. The carrier tape may be transported by the first driving means 204 or the second driving means 205. [ The driving means 205 can be rotated by the driving means 205 so that the carrier tape is transported to the predetermined position of the tape guide 203 and the electronic part can be picked up at the above described pickup position.

The travel distance of the tape can be controlled by the rotation control of the drive motor and the predetermined position and rotation of the transport means can be detected by the magnetic sensor and the rotation detection sensor as described above. And the pitch corresponding to the pick-up position can be determined. For example, when the homing to the pick-up position is started, the control unit corrects the information according to the absolute position of the sprocket and the correction value for the index according to the previously stored information, And starts the homing drive. This compensates for the deviation of the pick-up position according to the error described above, so that an operating error can be prevented. This operation process will be described below.

3 is a block diagram schematically illustrating an embodiment of a position correction method according to the present invention.

Referring to FIG. 3, a method for correcting a homing position of a carrier tape, in which a component according to the present invention is accommodated, comprises the steps of: storing an index of the absolute position of each tooth of the sprocket carrying the carrier tape; Storing a correction value between the indexed tooth and a homing position; Reading the absolute position of the tooth by a magnetic sensor; And synchronizing the rotor position of the motor driving the sprocket with the sprocket.

As described above, an index is assigned to each tooth of the sprocket and magnetic or magnetic field strength is stored (S31) on a storage medium such as, for example, a non-volatile memory at a predetermined distance for each index. The storage medium may be any memory that can be called the value stored by the control unit and may be located in a suitable device. The index corresponds to the sprocket's unique value and can be identified by magnetic force or magnetic field. For each index, a correction value for the homing position may be stored (S32). Then, the teeth of the sprocket are detected by the magnetic sensor and the absolute position of the sprocket can be detected (S33). And a correction value for a homing position according to a previously stored correction value can be calculated based on the detected absolute position. Generally, in the case of a BLDC (blushless DC) motor, there is a sensor type and a sensorless type, and the position of the permanent magnet of the rotor corresponding to the rotor through Hall elements and back EMF is It is judged within the control cycle. For example, the position of the rotor can be determined by measuring the point where the counter electromotive force becomes zero. However, it can not be detected whether the rotor is located at an angle within the range of 0 to 360 degrees. Therefore, it is necessary to detect the rotation of the sprocket through the rotation detection sensor and synchronize with the rotor position of the BLDC motor (S34).

When the absolute position of the sprocket is read and the rotor is synchronized, the control unit calls the correction value stored in the storage medium together with the homing command to precisely control the stop position at the end of the homing drive when the initial power is applied .

The feeder according to the present invention determines the absolute position of the sprocket and applies an intrinsic correction value according to the pre-stored position of the sprocket in the storage medium such as the non-volatile memory, The conveying position of the carrier tape can be repetitively made constant so that the component can be transferred to the predetermined pickup position. The feeder according to the present invention can determine the absolute position of the sprocket when the first power is turned on and the homing drive is performed so that a homing structure in which the transport position and the homing position of the carrier tape are the same can be provided even if the sprocket is positioned at any tooth Effect.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention . The invention is not limited by these variations and modifications, but is limited only by the claims appended hereto.

12: Sprocket 13: Tape guide
14: power transmission means 111: magnetic sensor
112: rotation detection sensor 113: fixing means
121: shaft connecting portion 122: self-generating unit
123: reference pitch unit 124: engaging unit
124a: connection unit 131: separation start portion
132: separation inducing portion 133: pickup portion
200: tape supply device 201: input module
202: Feed module 203: Tape guide
204, 205: driving means 206: conveying means

Claims (5)

An electric feeder for transporting a carrier tape in which a component is accommodated,
A sprocket (12) rotated by driving of the motor and having teeth engaged with the transfer hole of the carrier tape;
Absolute address index assigned to each tooth of the sprocket (12). A storage medium storing different magnetic force values for respective absolute address indexes and correction values between respective indexes and homing positions;
A self-generating unit (122) disposed along the circumferential surface of the sprocket (12) to generate at least one magnetic field different for each tooth;
A magnetic sensor 111 for detecting a magnetic field generated in the self-generating unit 122 and detecting an absolute address index assigned to each of the teeth; And
And a rotation detection sensor (112) for detecting rotation of the sprocket (12).  The spool (1) according to claim 1, wherein the sprocket (12) includes a reference pitch unit (123) formed at the same pitch as a tooth engaging with the transfer hole of the carrier tape along a circumferential surface, (123), the motor is synchronized with the sprocket (12). delete A method for correcting a homing position of a carrier tape in which a component is accommodated,
Storing an absolute address index assigned to each tooth of the sprocket carrying the carrier tape and a different magnetic force value for each absolute address index;
Storing a correction value between the indexed tooth and a homing position;
Reading the absolute position of the tooth by a magnetic sensor; And
Synchronizing the rotor position of the motor driving the sprocket,
Wherein the synchronization is detected by detecting a reference pitch unit formed to correspond to a pitch of each tooth of the sprocket to detect rotation of the sprocket.
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