TWI774322B - Rotary axis sensing device of sewing machine motor - Google Patents

Abstract

A rotating shaft sensing device of a sewing machine motor, comprising a magnet turntable, a first IC board and a second IC board, the magnet turntable is magnetized with an inner ring magnetic area, an outer ring magnetic area and an upper positioning magnetic area, The first IC board senses the rotation of the magnet turntable and directly captures the rotation of the rotating shaft, senses the inner ring magnetic area, outputs R, S, T pulse signals, and senses the outer ring magnetic area, outputs A, B pulse signals, as a motor drive It is used for control; and the rotation of the rotating shaft is captured by sensing the rotation of the magnet turntable through the second IC board, the upper positioning magnetic area is sensed, and the upper positioning pulse signal is output to control the stop position of the upper positioning needle of the sewing machine.

Description

Rotary axis sensing device of sewing machine motor

The present invention relates to a sensing device for a motor rotating shaft to accurately monitor the running state of the motor rotating shaft, in particular to a rotating shaft sensing device for a sewing machine motor.

The current sewing machine encoders can be roughly divided into two types: contact type and non-contact type according to their sensing methods. Contact encoders have the problem of wear and tear of parts. In order to avoid contact wear, relevant manufacturers have developed non-contact encoders, such as optical encoders and magnetic encoders.

Please refer to the new patent case of "Servo Motor Encoder" with Chinese Certificate No. M302831. The encoder in this case is an optical encoder. The servo motor encoder includes a light-shielding sheet and a sensing device. The light-shielding sheet is a circular body and is used to connect to the rear end of the servo motor shaft. The outer ring or the inner ring is concave with several grooves at equal intervals. , a plurality of light-transmitting holes are arranged in the inner or outer concentric rings, the sensing device is provided with a base that is combined with the rear surface of the servo motor, the base is provided with a bottom plate with perforations, and a circular arc is vertically extended outward from the periphery of the bottom plate A plug body shaped and surrounding the light-shielding plate, and three photo interrupters for detecting missing grooves and an optical encoder module for detecting each light-transmitting hole are combined around the plug body; accordingly, That is, the position and movement of the light-shielding plate can be detected by the photo-interrupter and the photo-encoding module, and the information can be encoded and output for detecting and controlling the action of the servo motor.

The aforementioned optical encoders are rotary optical encoders commonly used in sewing machines in the industry. However, the sewing machine operates by sewing fabrics, so many broken threads or lint will be generated during the sewing process. Broken threads or lint will adhere to the perforations and shades of the bottom plate The light-transmitting hole will affect the detection accuracy of the photo-interrupter, thus causing the timing error of the sewing machine to fail to operate normally.

In addition, among the non-contact encoders, the magnetic encoder also has the advantage of overcoming the wear problem of the contact encoder components, and is used to convert the mechanical rotation angle of the rotating shaft into a digital or analog signal to realize signals such as angle, linear displacement, and rotational speed. Compared with the rotary optical encoder, the output does not have the problem of affecting the accuracy of its sensing in harsh working environments such as oily or dusty (or broken threads or cotton wool in the aforementioned sewing machine). The application of the magnetic encoder to the sewing machine will solve the problems encountered by the aforementioned optical encoder.

For magnetic encoders, please refer to my country's Certificate No. M473407 "Device for synchronizing the direct-drive motor of a sewing machine and a magnetic encoder", which is about a device for synchronizing the direct-drive motor of a sewing machine and a magnetic encoder. The main technical means are in The output shaft of the motor is sleeved with a transmission gear, and a mounting seat is additionally assembled on the casing of the motor to install an additional shaft, and a driven gear is sleeved on the shaft. The transmission gear and the driven gear A transmission belt is meshed together, and then a magnetic element is placed on the shaft, and a corresponding sensor is arranged in the path through which the magnetic element passes. The transmission relationship between the moving gears rotates synchronously, and the magnetic element also rotates with the shaft. At this time, the sensor can measure the required data according to the magnetic field change of the rotating magnetic element. In other words, the conventional Most of the technology is to add a transmission mechanism on the output shaft to express the rotation state on another driven shaft, and then use the shaft to drive the magnetic element to rotate to monitor and control and generate codes.

However, this kind of technical means of adding a hanging transmission mechanism to drive an additional shaft is prone to unnecessary loss of output and transmission loss, belt wear and dust, belt transmission slippage, belt wear and tear. Rotational resonance... and many other problems, which will lead to the problem of detection distortion. Furthermore, it will also take up too much space for the motor configuration, affect heat dissipation, etc., and the magnetic components cannot directly perform physical level adjustment. through Positioning deviation correction and adjustment through electronic parameter setting is also difficult for those who are unfamiliar with the control function, and it is prone to setting errors, which affects the product yield. Optimization and improvement are the key points of the present invention.

The main purpose of the present invention is to provide a method for directly sensing the rotating shaft of a sewing machine motor by using a dual-sensing IC board, so that the operation of the sewing machine is more accurate and the production efficiency and yield are improved.

In order to achieve the above-mentioned purpose, the technical means adopted in the present invention include: a magnet turntable, which is sleeved into a ring groove fixed on the rotating shaft with a central circular hole, so that the magnet turntable rotates synchronously with the rotating shaft, and the magnet turntable is filled with The magnetic field has an inner ring magnetic area and an outer ring magnetic area, and an upper positioning magnetic area is arranged between the inner ring magnetic area and the outer ring magnetic area; a first IC board is fixed on the back cover and used for to sense the inner ring magnetic area and the outer ring magnetic area to output pulse signals of R, S, T and pulse signals of A and B respectively; a second IC board is fixed on the back cover for Sensing the upper positioning magnetic area, outputting the upper positioning pulse signal, and controlling the motor operation with the pulse signal output by the first IC board; since the magnet turntable is directly fixed on the rotating shaft, it rotates synchronously with the rotating shaft , the absolute position of the rotating shaft can be sensed, so that the signal generated by it is not distorted.

The sensing device is provided with a positioning mechanism on the back cover, and the positioning mechanism is fixed with the second IC board.

The back cover is provided with at least one first stud for fixing the first IC board, and the positioning mechanism is provided with a first opening corresponding to the first stud for the first stud to pass through; the positioning mechanism The peripheral edge of the mechanism has a plurality of lugs, and an adjustment hole for locking is penetrated at each lug. When loosening, the positioning mechanism can be rotated to adjust the relative position of the second IC board and the upper positioning magnetic area, and The first opening rotates relative to the first stud; the positioning mechanism has a boss, and a groove is formed between the boss and each of the bosses, so that a turntable cover can be inserted into the groove.

The perimeter of the positioning mechanism has a plurality of lugs, and an adjustment hole for locking is inserted through each of the lugs. When loosening, the positioning mechanism can be rotated to adjust the second IC board and the upper positioning magnetic area. The positioning mechanism has a boss, and a groove is formed between the boss and each of the lugs, so that a turntable cover can be inserted into the groove.

The sensing device further includes a turntable cover, which is sleeved inside the annular groove of the rotating shaft and fixed on the rear cover to cover the magnet turntable and the outside of the first IC board.

The sensing device further includes a turntable cover, the turntable cover is disposed on the outside of the magnet turntable and the first and second IC boards and is fixed on the rear cover.

The inner ring magnetic area of the magnet turntable is magnetized with at least 4 poles arranged according to the polarity, so as to be sensed by the first IC board.

The outer ring magnetic area of the magnet turntable is arranged and magnetized according to the polarity to have 2 times the number of poles for sensing by the first IC board; the number of poles of the outer ring magnetic area is 60 poles.

The upper positioning magnetic area of the magnet turntable is magnetized with three poles, which are arranged according to one of NSN polarity or SNS polarity, for the second IC board to sense.

The magnet turntable is provided with a lower positioning magnetic region at a position where the upper positioning magnetic region is opposite to 180 degrees, so that the second IC board can sense the lower positioning magnetic region correspondingly, so as to output a lower positioning pulse signal to control the sewing machine. The lower positioning needle stop position; the magnet turntable further includes a non-magnetic pole area, the height of the non-magnetic pole area is less than the height of the lower positioning magnetic area; the height of the non-magnetic pole area is reduced by 0.2~0.6mm; Height is 0.4mm.

The magnet turntable further includes a pole-free area, and the height of the pole-free area is smaller than the height of the inner ring magnetic area, the outer ring magnetic area and the upper positioning magnetic area; the height of the non-magnetic pole area is reduced by 0.2~0.6mm. time; the reduced height of the pole-free area is 0.4mm.

The material of the magnet turntable is plastic material and iron oxide magnet.

The sensing device further includes a hand wheel fixed on the rotating shaft.

10: Motor

11: Rotary axis

111: Ring groove

12: Back cover

121: First Stud

20: Magnet Turntable

201: Inner Ring Magnetic Region

202: Outer ring magnetic area

203: Upper positioning magnetic area

204: Lower positioning magnetic area

205: No magnetic pole area

21: Flange

211: Center round hole

22: Gap adjustment sheet

23: C-type buckle

30: The first IC board

31: Screws

40: Second IC board

41: Screws

50: Positioning mechanism

51: Boss

52: Center hole

53: The first opening

54: lugs

541: Adjustment hole

55: groove

56: Screws

57: Second Stud

60: Turntable cover

61: Screws

70: Handwheel

Figure 1 is a combined perspective view of a preferred embodiment of the present invention; Figure 2 is an exploded schematic view of a preferred embodiment of the present invention; Figure 3 is a detailed exploded schematic view of the preferred embodiment of the present invention; Figure 4 is the present invention A schematic diagram of the magnetic area of the magnet turntable in the preferred embodiment; Figure 4A is another schematic diagram of the magnetic area of the magnet turntable in the preferred embodiment of the present invention; Figure 5 is a schematic cross-sectional view of the preferred embodiment of the present invention; Figure 6 is The schematic diagram of the positioning mechanism in the preferred embodiment of the present invention before rotation; Figure 6A is the schematic diagram of the positioning mechanism in the preferred embodiment of the present invention after rotation; Figure 7 is the first IC board in the preferred embodiment of the present invention used alone schematic diagram.

Please refer to FIGS. 1-3, which are schematic diagrams of a preferred embodiment of the present invention. The sensing device of the present invention is correspondingly disposed at the position of the rotating shaft 11 of the motor 10, and includes a magnet turntable 20, a first IC The board 30 , a second IC board 40 , a positioning mechanism 50 and a turntable cover 60 .

As shown in FIG. 3 , the motor 10 is provided with a first stud 121 on the rear cover 12 , and the positioning mechanism 50 has a boss 51 with a smaller area and a central hole 52 extending therethrough on one side of the main body of the positioning mechanism 50 . A first opening 53 is preset at the position of the stud 121 for the first stud 121 to pass through. The number of the first studs 121 can also be increased or decreased under the premise that the first IC board 30 can be locked.

The positioning mechanism 50 also has a plurality of lugs 54 extending outward from the periphery of the body, so that a groove 55 is formed between the boss 51 and the lugs 54, as shown in FIG. Arc-shaped adjustment hole 541 . In this embodiment, the positioning mechanism 50 has three lugs 54, which can be increased or decreased as required.

During assembly, the positioning mechanism 50 is inserted into the rotating shaft 11 through the central hole 52 , and the first stud 121 is inserted through the first opening 53 , and finally the screw 56 is passed through the adjustment hole 541 to fix the positioning mechanism 50 on the rear cover 12 .

The first IC board 30 is fixed on the first stud 121 passing through the first opening 53 with the screw 31 , and the second IC board 40 is locked on the second stud 57 of the positioning mechanism 50 with the screw 41 .

The positioning mechanism 50 in this embodiment has a pair of second studs 57 for locking the second IC board 40 . When necessary, the position of the second studs 57 can be changed, or as shown in FIG. 3 . , the second studs 57 are provided at different angles in advance for optional use. On the premise that the second IC board 40 can be locked, the number of the second studs 57 can also be increased or decreased.

The magnet turntable 20 has a disc-shaped body and a flange 21 is formed on the body to surround the central circular hole 211 . The magnet turntable 20 in this embodiment is made of plastic material and iron oxide magnet, but the material is not limited to these.

During assembly, one side of the magnet turntable 20 and the gap adjusting piece 22 are inserted into the rotating shaft 11 together, and then the C-shaped retaining ring 23 is correspondingly fastened to the ring groove 111 of the rotating shaft 11 to be fixed on the rotating shaft as shown in FIG. 5 . 11 on the other side, and the other side has the flange 21 for the turntable cover 60 to be inserted into, so that the magnet turntable 20 is clamped between the ring groove 111 of the rotating shaft 11 and the turntable cover 60 .

After the turntable cover 60 is inserted into the rotating shaft 11 , the magnet turntable 20 , the positioning mechanism 50 , the second IC board 40 on the second stud 57 , and the first IC on the first stud 121 passing through the positioning mechanism 50 can be inserted into the turntable cover 60 . As shown in FIG. 5, the plates 30 are all sheathed together in the accommodating space formed by the positioning mechanism 50, and the turntable cover 60 can be correspondingly embedded in the groove 55 between the boss 51 and the lug 54, and then screw 61 is locked on the rear cover 12 .

As shown in FIG. 4, the magnet turntable 20 is magnetized with an inner ring magnetic area 201, an outer ring magnetic area 202 and an upper positioning magnetic area 203. The outer ring magnetic area 202 is located at the outer ring around the body of the magnet turntable 20, The inner ring magnetic area 201 is located at the outer ring around the central circular hole 211 of the magnet turntable 20 , and the upper positioning magnetic area 203 is located relatively between the inner ring magnetic area 201 and the outer ring magnetic area 202 .

The inner ring magnetic area 201 is equally divided as shown in the figure and magnetized with at least 4 poles arranged according to the NSNS polarity. The number of poles; the outer ring magnetic area 202 is equally divided as shown in the figure and magnetized according to the polarity of NSNS, there are 30 pole pairs (60 poles), in fact, it can be increased in multiples of 2 poles (NS) according to the needs; the upper positioning magnetic area 203 is as follows As shown in the figure, there are 3 magnetization poles arranged according to the NSN polarity, in fact, it depends on the different sensing devices. The polarity arrangement of SNS can be selected.

The first IC board 30 is fixed on the first stud 121 passing through the positioning mechanism 50 , and is relatively positioned between the magnet turntable 20 and the positioning mechanism 50 , for correspondingly sensing the inner ring magnetic region 201 of the magnet turntable 20 and the outer magnetic region 201 of the magnet turntable 20 . Ring magnetic region 202 .

The first IC board 30 cooperates with the inner ring magnetic area 201 of the magnet turntable 20 for detection by using the magnetic principle to output pulse signals of R, S and T, and also cooperates with the outer ring magnetic area 202 of the magnet turntable 20 for sensing by the magnetic principle. It is detected to output the pulse signals of A and B.

The sensing device uses the first IC board 30 to output the pulse signals of R, S, T and the pulse signals of A and B, and transmit the signals to the controller for processing (not shown in the figure) by electrical connection, as the motor drive control, for example Detecting the rotation direction, speed, etc. of the rotating shaft 11 can obtain the best control effect.

The second IC board 40 is fixed on the second studs 57 with screws 41 , and is relatively positioned on the magnet turntable 20 and the positioning mechanism 50 , for correspondingly sensing the positioning magnetic region 203 on the magnet turntable 20 .

The second IC board 40 cooperates with the upper positioning magnetic area 203 of the magnet turntable 20 for detection by using the principle of magnetic induction to output the upper positioning pulse signal, and then transmits the upper positioning pulse signal to the controller for processing through the electrical connection (not shown in the figure) , as the upper positioning needle stop position for controlling the sewing machine.

According to operational requirements, a set of 3-pole lower positioning magnetic regions 204 can be set at the position where the upper positioning magnetic region 203 is opposed to 180 degrees. As shown in FIG. 4A, similar to the upper positioning magnetic region 203, they are arranged according to the NSN polarity. It can also be arranged according to the SNS polarity, corresponding to the lower positioning position of the motor. The second IC board 40 cooperates with the lower positioning magnetic area 204 to sense and detect by magnetic principle, so as to output the lower positioning pulse signal, which is used to control the stop position of the lower positioning needle of the sewing machine.

In order to avoid the phenomenon of magnetic interference during magnetization, the heights of the inner ring magnetic region 201, the outer ring magnetic region 202 and the non-magnetic region 205 other than the upper positioning magnetic region 203 or the lower positioning magnetic region 204 in Fig. The ring magnetic region 201, the outer ring magnetic region 202, and the upper positioning magnetic region 203 or the lower positioning magnetic region 204 are low. The height reduction range of the non-magnetic pole region 205 is between 0.2 and 0.6 mm, and the best is 0.4 mm.

The second IC board 40 can also adjust the second IC board 40 by loosening the screws 56 originally locked in the adjustment holes 541 as shown in FIG. 6 , and then directly rotating the positioning mechanism 50 as shown in FIG. 6A . The position of the second IC board 40 on the stud 57 is used to adjust the relative position of the second IC board 40 and the upper positioning magnetic area 203, and to fine-tune the upper positioning point, which is convenient for unfamiliar operators to adjust. According to actual needs, the second studs 57 can also be directly disposed on the back cover 12 at appropriate positions to cooperate with the magnet turntable 20 for detection, omitting the function of adjustment.

During adjustment, the first opening 53 on the positioning mechanism 50 for the first stud 121 to pass through and the diameter and shape of the adjustment hole 541 can cooperate with each other as shown in FIG. 6A. When the positioning mechanism 50 rotates, the first opening 53 is used. The structure of keeping the first stud 121 pierced out, so that the positioning mechanism 50 can rotate relative to the first stud 121 through the first opening 53 without affecting the rotation of the positioning mechanism 50 . Under the premise of not affecting the rotation of the positioning mechanism 50 , the position of the first stud 121 , the fixed structure of the first IC board 30 , and the shape of the positioning mechanism 50 body can also be selectively changed accordingly.

The first IC board 30 in this embodiment can also be used alone with the magnet turntable 20 . When the first IC board 30 is used alone, as shown in FIG. 7 , the first IC board 30 can be directly locked on the back cover 12 The first stud 121 on the top is matched with the corresponding magnetic area of the magnet turntable 20 to output a pulse signal, and another external positioning signal device is added to control the operation of the motor 10 .

In the present invention, as shown in FIG. 5, a hand wheel 70 can be optionally added. The hand wheel 70 is directly fixed on the rotating shaft 11, so that the hand wheel 70 can directly drive the rotating shaft 11, and the magnet turntable 20 can also be synchronized. Sensing the rotation of the handwheel 70; a heat shield (not shown in the figure) can also be added to cover the motor 10 for heat insulation.

In the present invention, because the magnet turntable 20 is directly arranged on the rotating shaft 11 and rotates synchronously with the rotating shaft 11, the generated induction signal is obtained from the absolute position, and the signal will not be distorted, and since all values are directly captured from the rotating shaft 11. Therefore, compared with the general indirect acquisition method, it can generate more accurate and undistorted signals, and more absolute monitoring and control values, so that the operation of the sewing machine motor can obtain the best control effect.

The present invention uses magnetic induction to achieve motor drive and positioning control, so it is not afraid of oil and gas or water vapor pollution, as well as the covering of cotton wool and dust, so that the operation of the sewing machine motor can obtain the best control effect.

The above-listed embodiments are intended to illustrate the preferred and possible implementation modes of the present invention, and are not intended to limit the patent scope of the present invention. Those with equal replacement shall belong to the scope of the patent application scope of the present invention.

10: Motor

12: Motor back cover

60: Turntable cover

70: Handwheel

Claims (21)

A rotating shaft sensing device of a sewing machine motor is used to be installed with a motor. The motor has a rotating shaft on its rear cover. The sensing device includes: a magnet turntable, which is sleeved and fixed on the rotating shaft with a central circular hole. A ring groove of the shaft makes the magnet turntable rotate synchronously with the rotating shaft. The magnet turntable is magnetized with an inner ring magnetic area and an outer ring magnetic area, and a magnetic area is arranged between the inner ring magnetic area and the outer ring magnetic area. The upper positioning magnetic area; a first IC board, fixed on the back cover, is used to sense the inner magnetic area and the outer magnetic area, so as to output the pulse signals of R, S, T and output A, B respectively pulse signal; a second IC board, fixed on the back cover, used to sense the upper positioning magnetic area, output the upper positioning pulse signal, and control the motor operation in coordination with the pulse signal output by the first IC board ; Because the magnet turntable is directly fixed on the rotating shaft and rotates synchronously with the rotating shaft, the absolute position of the rotating shaft can be sensed, so that the generated signal is not distorted. The rotating shaft sensing device of a sewing machine motor as claimed in claim 1, wherein the sensing device is provided with a positioning mechanism on the rear cover, and the positioning mechanism is fixed with the second IC board. The rotation axis sensing device of a sewing machine motor as claimed in claim 2, wherein the rear cover is provided with at least one first stud for fixing the first IC board, and the positioning mechanism is provided with a first stud corresponding to the first stud an opening for passing through the first stud. The rotation axis sensing device of a sewing machine motor as claimed in claim 3, wherein the perimeter of the positioning mechanism has a plurality of lugs, and an adjustment hole for locking penetrates through each of the lugs, and the positioning mechanism can be rotated when released , adjust the relative position of the second IC board and the upper positioning magnetic area, and rotate relative to the first stud through the first opening. The rotation axis sensing device for a sewing machine motor as claimed in claim 2, wherein the perimeter of the positioning mechanism has a plurality of lugs, and an adjustment hole for locking penetrates through each of the lugs, and the positioning mechanism can be rotated when released , to adjust the relative position of the second IC board and the upper positioning magnetic area. The rotary shaft sensing device for a sewing machine motor as claimed in claim 4 or 5, wherein the positioning mechanism has a boss, and a groove is formed between the boss and each of the bosses, so that a turntable cover can be inserted into the groove. The rotating shaft sensing device of a sewing machine motor as claimed in claim 1, wherein the sensing device further comprises a turntable cover, the turntable cover is sleeved inside the annular groove of the rotating shaft and fixed on the rear cover to cover the The magnet turntable is outside the first IC board. As claimed in claim 1 or 2, the rotating shaft sensing device of a sewing machine motor, wherein the sensing device further comprises a turntable cover, and the turntable cover is arranged on the outside of the magnet turntable and the first and second IC boards and is fixed on the outside of the magnet turntable and the first and second IC boards Cover the back. The rotating shaft sensing device of a sewing machine motor as claimed in claim 1, wherein the inner ring magnetic region of the magnet turntable is magnetized with at least 4 poles arranged in accordance with the polarity for sensing by the first IC board. The rotating shaft sensing device of a sewing machine motor as claimed in claim 1, wherein the outer magnetic area of the magnet turntable is arranged and magnetized with a number of poles that are twice as many as possible for the first IC board to sense. The rotating shaft sensing device for a sewing machine motor according to claim 10, wherein the number of poles in the outer ring magnetic region is 60 poles. The rotary shaft sensing device for a sewing machine motor as claimed in claim 1, wherein the upper positioning magnetic region of the magnet turntable is magnetized with three poles, arranged according to either NSN polarity or SNS polarity, for the second IC board to sense . The rotating shaft sensing device for a sewing machine motor as claimed in claim 1, wherein the magnet turntable is provided with a lower positioning magnetic region at a position 180 degrees opposite to the upper positioning magnetic region, so that the second IC board can sense the lower positioning magnetic region correspondingly. Position the magnetic area to output the lower positioning pulse signal to control the stop position of the lower positioning needle of the sewing machine. The rotating shaft sensing device for a sewing machine motor of claim 13, wherein the magnet turntable further includes a pole-free area, and the height of the pole-free area is smaller than the height of the lower positioning magnetic area. The rotating shaft sensing device of a sewing machine motor according to claim 14, wherein the height of the non-magnetic pole region is reduced by between 0.2 and 0.6 mm. The rotating shaft sensing device of a sewing machine motor as claimed in claim 15, wherein the reduced height of the non-magnetic pole region is 0.4 mm. As claimed in claim 1 or 2, the rotating shaft sensing device of a sewing machine motor, wherein the magnet turntable further includes a pole-free area, and the height of the pole-free area is smaller than the inner magnetic area, the outer magnetic area and the upper positioning area. The height of the magnetic sector. The rotation axis sensing device of a sewing machine motor according to claim 17, wherein the height of the non-magnetic pole region is reduced by between 0.2 and 0.6 mm. The rotating shaft sensing device for a sewing machine motor as claimed in claim 18, wherein the reduced height of the non-magnetic pole region is 0.4 mm. As claimed in claim 1 or 2, the rotating shaft sensing device of a sewing machine motor, wherein the material of the magnet turntable is a plastic material and an iron oxide magnet. The rotating shaft sensing device of a sewing machine motor as claimed in claim 1, wherein the sensing device further comprises a hand wheel fixed on the rotating shaft.

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