JP3778089B2 - Electromagnetic drive for weft insertion control in looms - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electromagnetic drive device for weft insertion control that switches a locking body between a release permissible position that permits withdrawal of a weft thread that is stored for length measurement and a release prevention position that prevents weft withdrawal from being released.
[0002]
[Prior art]
The timing of drawing and unwinding the weft from the winding type weft length measuring and storage device is determined at a predetermined timing in one weft insertion cycle. The weft drawing / unwinding is performed by releasing the pin-shaped locking body engaged with the yarn winding surface in the winding type weft length measuring and storage device from the yarn winding surface. Since there is enough time to release the latching body from the thread winding surface by the time the weft is pulled out and unwound, the movement speed of the latching body to release the locking body from the thread winding surface is increased. The degree of demand is not high. However, when stopping the withdrawal of the weft thread during the unwinding of the drawer, it is necessary to move the locking body released from the thread winding surface to a position where it engages with the thread winding surface at high speed. If the timing at which the engaging body released from the thread winding surface is engaged with the thread winding surface is delayed, the wefts on the thread winding surface are pulled out and unwound.
[0003]
JP-A-6-184870 and JP-A-7-18543 disclose an electromagnetic driving device that performs both movement from one position to the other of the position where the thread winding surface is disengaged and the position engaged with the thread winding surface. Is disclosed. Such an electromagnetic drive device is advantageous in moving the locking body detached from the thread winding surface to a position where it engages with the thread winding surface at high speed.
[0004]
[Problems to be solved by the invention]
However, in order to further increase the speed of the loom, it is necessary to further increase the speed at which the engaging body released from the yarn winding surface is moved to a position where it engages with the yarn winding surface.
[0005]
An object of the present invention is to further increase the speed at which the locking body is moved from the position separated from the thread winding surface to the position engaging with the thread winding surface.
[0006]
[Means for Solving the Problems]
To this end, the present invention includes a mover that includes, as a part, a latching body that can be switched between a release permissible position that allows withdrawal of a weft thread that is stored for length measurement and a release prevention position that inhibits weft withdrawal. The engaging member is moved from the release-preventing position to the release-permitted position by electromagnetic attraction acting on the mover by energizing the first coil, and the mover is applied to the mover by energizing the second coil. The invention relates to an electromagnetic drive device for weft insertion control that moves the locking body from the release-permitted position to the release-preventing position by an electromagnetic attracting force that acts. The coil-side magnetic path cross-sectional area of the mover is made larger than the magnetic path cross-sectional area of the mover on the first coil side, the locking body is a non-magnetic body, and the magnetic body portion of the mover is cylindrical As part The first coil on the inner peripheral surface of the cylindrical portion of the mover is formed by fitting and coupling the locking body to the cylindrical portion, making the diameter of the outer peripheral surface of the cylindrical portion of the mover constant. The diameter on the side was made larger than the diameter on the second coil side on the inner peripheral surface of the cylindrical portion of the mover .
[0007]
The magnitude relation of the magnetic path cross-sectional area is such that the thrust for moving the locking body from the unwinding permission position to the unwinding prevention position is used to move the locking body from the unwinding prevention position to the unwinding permission position. Make it bigger than thrust.
[0009]
In addition, the cylindrical shape of the magnetic body portion of the mover is effective for reducing the weight of the mover .
[0011]
Moreover, the setting of the magnitude relation of the diameter is simple in obtaining the desired magnitude relation of the magnetic path cross-sectional area.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. 1 and 2.
[0013]
FIG. 2A shows a weft length measuring and storing device 12 and an electromagnetic drive device 13 of a winding method for measuring and storing the weft Y drawn from the weft cheese 11. The weft Y wound around the yarn winding surface 121 of the weft length measuring storage device 12 is drawn out from the yarn winding surface 121 by the air injection action of the weft insertion main nozzle 14 and inserted. The weft Y drawn and unwound from the bobbin winding surface 121 is detected by the weft unwinding detector 15. Pull-out unwinding detection information obtained by the weft unwinding detector 15 is sent to the control device 16. The control device 16 controls the excitation and demagnetization of the electromagnetic drive device 13 based on the loom rotation angle detection information obtained by the rotary encoder 17 that detects the rotation angle of the loom and the drawing unwinding detection information obtained from the weft unwinding detector 15. To do.
[0014]
FIG. 1 shows the internal structure of the electromagnetic drive device 13. An annular magnetic path forming plate 19 is fixed to the inner peripheral surface of a cylindrical case 18 made of a magnetic material. The upper opening of the case 18 is closed by a lid plate 181. The magnetic path forming plate 19 partitions the inside of the case 18 into a pair of upper and lower accommodation chambers. A cylindrical bobbin 20 is accommodated in the upper accommodation chamber, and a first coil 21 is supported on the bobbin 20. The cylindrical portion of the bobbin 20 is fitted with a magnetic stator 22. A cylindrical bobbin 23 is accommodated in the lower accommodation chamber, and a second coil 24 is supported on the bobbin 23. The cylindrical portion of the bobbin 23 is fitted with a magnetic stator 25. The inner diameters of the bobbins 20 and 23 and the inner diameter of the magnetic path forming plate 19 are the same.
[0015]
A non-magnetic guide cylinder 26 is fitted to the lower part of the cylindrical part of the bobbin 20, the inner diameter part of the magnetic path forming plate 19 and the upper part of the cylindrical part of the bobbin 23. The guide cylinder 26 is sandwiched and held between the pair of stators 22 and 25. Between the upper end of the guide cylinder 26 and the lower end of the stator 22, a rubber shock absorber 27 is interposed. A rubber cushion 28 is interposed between the lower end of the guide cylinder 26 and the upper end of the stator 25.
[0016]
In the cylinder of the guide cylinder 26, a thrust receiving portion 30 made of a magnetic material, which is a part of the movable element 29, is accommodated. The thrust receiving portion 30 has a cylindrical shape, and a cylindrical locking body 31 made of a non-magnetic material (for example, ceramic) is fitted and coupled to the cylindrical portion of the thrust receiving portion 30. A guide hole 183 is provided in the lower end wall 182 of the case 18, and the locking body 31 is inserted into the guide hole 183 through the buffer body 28 and the stator 25.
[0017]
As shown in FIG. 2C, the diameter of the outer peripheral surface of the thrust receiving portion 30 is a constant diameter Do. The diameter of the inner peripheral surface of the thrust receiving portion 30 is different between the upper side (first coil 21 side) and the lower side (second coil 24 side). When the upper side inner diameter is d1 and the lower side inner diameter is d2, a magnitude relationship of d1> d2 is set. The locking body 31 is fitted to the inner diameter portion on the lower side where the inner diameter = d2. The locking body 31 is coupled and fixed to the thrust receiving portion 30 by adhesion.
[0018]
FIG. 1 shows a state in which the locking body 31 is in an unwinding prevention position for preventing the weft Y from being pulled out, and the weft Y is undrawn from being unwound. When the locking body 31 is in the unwinding prevention position, the lower end of the thrust receiving portion 30 is in contact with the buffer body 28, and the thrust receiving portion 30 whose inner diameter = d1 is in the inner diameter portion of the magnetic path forming plate 19. The inner diameter large diameter portion 301 on the upper side of each is opposed.
[0019]
FIG. 2B shows a state in which the locking body 31 is in an unwinding allowable position where the weft Y is allowed to be unwound. When the locking body 31 is in the unwinding-permitted position, the upper end of the thrust receiving portion 30 is in contact with the buffer body 27, and the thrust receiving portion 30 having an inner diameter = d2 is formed on the inner diameter portion of the magnetic path forming plate 19. The inner diameter small diameter portion 302 on the lower side of the is opposed.
[0020]
The control device 16 grasps the arrival of the weft insertion start timing based on the loom rotation angle information obtained from the rotary encoder 17. When the weft insertion start timing approaches, the control device 16 starts energizing the first coil 21. The mover 29 in the unwinding prevention position shifts to the unwinding allowable position when the first coil 21 is energized, and the drawing and unwinding of the weft Y is started. When the weft unwinding detector 15 detects weft unwinding a predetermined number of times, the control device 16 stops energizing the first coil 21 and starts energizing the second coil 24. The mover 29 in the unwinding allowable position shifts to the unwinding preventing position by energizing the second coil 24, and the weft Y is prevented from being pulled out.
[0021]
When the loom is in a stopped state and neither the first coil 21 nor the second coil 24 is energized, the mover 29 remains in the unwinding prevention position due to its own weight.
[0022]
The following effects can be obtained in the first embodiment.
(1-1) In FIG. 1, when the first coil 21 is energized, magnetic flux passing through the stator 22, the case 18, the magnetic path forming plate 19, and the inner diameter large diameter portion 301 of the thrust receiving portion 30 is generated. To do. Accordingly, an electromagnetic attractive force is generated between the thrust receiving portion 30 and the stator 22. In FIG. 2B, when the second coil 24 is energized, a magnetic flux passing through the stator 25, the case 18, the magnetic path forming plate 19, and the inner diameter small diameter portion 302 of the thrust receiving portion 30 is generated. Accordingly, an electromagnetic attractive force is generated between the thrust receiving portion 30 and the stator 25.
[0023]
The magnetic path cross-sectional area S1 in the inner diameter / large diameter portion 301 is represented by π [(Do / 2) ² − (d1 / 2) ² ]. The magnetic path cross-sectional area S2 in the small inner diameter portion 302 is represented by π [(Do / 2) ² − (d2 / 2) ² ]. That is, S1 <S2. Assuming that the supply current values for the first coil 21 and the second coil 24 are the same, the electromagnetic attractive force (that is, thrust) generated between the thrust receiving portion 30 and the stator 25 is fixed to the thrust receiving portion 30. It becomes larger than the electromagnetic attractive force (that is, thrust) generated between the child 22. Therefore, the speed at which the mover 29 moves from the unwinding permission position to the unwinding prevention position is faster than the speed at which the mover 29 moves from the unwinding prevention position to the unwinding permission position. This brings about an increase in the moving speed of the locking body 31 from the unwinding permission position to the unwinding prevention position.
[0024]
(1-2) The thrust receiving portion 30 which is a magnetic part of the mover 29 is a cylindrical portion. The cylindrical shape of the thrust receiving portion 30 is effective for reducing the weight of the mover 29. The weight reduction of the mover 29 is effective in increasing the moving speed of the mover 29. Further, the weight reduction of the movable element 29 can suppress the collision damage of the movable element 29 at the unwinding prevention position and the unwinding allowable position, and the durability of the movable element 29 is improved.
[0025]
(1-3) The locking body 31 has a cylindrical shape. The cylindrical shape of the locking body 31 is effective for reducing the weight of the mover 29.
(1-4) The diameter of the inner peripheral surface of the thrust receiving portion 30 that is the cylindrical portion of the mover 29 is different between the inner diameter large diameter portion 301 and the inner diameter small diameter portion 302. Such setting of the magnitude relation of the diameter is simple in obtaining a desired magnitude relation of the magnetic path cross-sectional area.
[0026]
Next, Reference Example 1 in FIG. 3 will be described. The same reference numerals are used for the same components as those in the first embodiment.
The mover 29A in Reference Example 1 is integrally formed of a magnetic material. A wear-resistant film 32 is provided on the outer peripheral surface of the locking body 31. The film 32 is formed by depositing diamond-like carbon, titanium nitride, or the like by physical vapor deposition or chemical vapor deposition.
[0027]
Next, Reference Example 2 in FIGS. 4A and 4B will be described. The same reference numerals are used for the same components as those in the first embodiment.
The inner diameter of the thrust receiving portion 30B of the mover 29B in Reference Example 2 is constant, but the outer diameter of the thrust receiving portion 30B is different between the upper side and the lower side. Assuming that the outer diameter on the upper side is d3 and the outer diameter on the lower side is d4, a magnitude relationship of d3 <d4 is set. When the locking body 31 is in the unwinding prevention position, the outer diameter small diameter portion 303 on the upper side of the thrust receiving portion 30B whose outer diameter = d3 is opposed to the inner diameter portion of the magnetic path forming plate 19. When the locking body 31 is in the unwinding-permitted position, the outer diameter large diameter portion 304 on the lower side of the thrust receiving portion 30B whose outer diameter = d4 is opposed to the inner diameter portion of the magnetic path forming plate 19.
[0028]
In Reference Example 2 , the same effect as in the first embodiment can be obtained.
Next, reference example 3 in FIGS. 5A and 5B will be described. The same reference numerals are used for the same components as those in the first embodiment.
[0029]
Although the inner diameter and the outer diameter of the thrust receiving portion 30C of the mover 29C in Reference Example 3 are both constant, a plurality of notches 305 are formed in the thrust receiving portion 30C. The notch 305 makes a difference in the magnetic path cross-sectional area between the upper side and the lower side of the thrust receiving portion 30C and reduces the weight of the mover 29C.
[0030]
Next, Reference Example 4 in FIG. 6 will be described. The same reference numerals are used for the same components as those in the first embodiment.
A cylindrical first thrust receiving portion 33 and a cylindrical second thrust receiving portion 34 are fitted to the locking body 31 of the mover 29D in Reference Example 4 . The wall thickness of the first thrust receiving portion 33 made of magnetic material is made thinner than the wall thickness of the second thrust receiving portion 34 made of magnetic material. Such a difference in wall thickness makes a difference in magnetic path cross-sectional area between the first thrust receiving portion 33 and the second thrust receiving portion 34. When the locking body 31 is in the unwinding prevention position, the first thrust receiving portion 33 faces the inner diameter portion of the magnetic path forming plate 19. When the locking body 31 is in the unwinding allowable position, the second thrust receiving portion 34 faces the inner diameter portion of the magnetic path forming plate 19.
[0031]
In Reference Example 4 , the same effect as in the first embodiment can be obtained.
In the present invention, the following embodiments are also possible .
[0032]
(2) In Reference Example 1 , the solid mover is integrally formed of a magnetic material.
(3) In the first embodiment, a holding spring having a weak spring force is interposed between the mover 29 and the stator 22. This holding spring keeps the locking body 31 in the unwinding prevention position when the electromagnetic driving device is used so that the locking body 31 protrudes upward from the case 18.
[0035]
【The invention's effect】
As described above in detail, in the present invention, the magnetic path cross-sectional area on the second coil side of the mover is made larger than the magnetic path cross-sectional area on the first coil side of the mover. There is an excellent effect that it is possible to further increase the speed of moving the locking body to the wrinkle prevention position.
[Brief description of the drawings]
FIG. 1 is a side sectional view showing a first embodiment.
FIG. 2A is a side view. (B) is a sectional side view showing a state where the locking body is in the unwinding allowable position. (C) is a principal part expanded side sectional view.
FIG. 3 is an enlarged side sectional view showing a main part of Reference Example 1 ;
FIG. 4 shows Reference Example 2 , (a) is a side sectional view. (B) is a principal part expanded side sectional view.
FIG. 5 shows Reference Example 3 , wherein (a) is an enlarged side cross-sectional view of the main part. (B) is the sectional view on the AA line of (a).
6 is a side sectional view showing Reference Example 4. FIG.
[Explanation of symbols]
13: Electromagnetic drive device. 21: First coil. 24. Second coil. 29, 29A, 29B, 29C, 29D ... movers. 30, 30 </ b> B, 30 </ b> C—thrust receiving portion that is a cylindrical portion.

Claims (1)

A mover including a locking body that is switched to a release permissible position that allows the withdrawal of the weft yarn that is stored for length measurement to be released and a release prevention position that prevents the weft from being pulled out is provided. The engagement body is moved from the release prevention position to the release permission position by an electromagnetic attraction force acting on the mover by energization, and by an electromagnetic attraction force acting on the mover by energization to the second coil. In the electromagnetic drive device for weft insertion control that moves the locking body from the release permission position to the release prevention position,
The magnetic path cross-sectional area on the second coil side in the mover is made larger than the magnetic path cross-sectional area on the first coil side in the mover ,
The locking body is a non-magnetic body, the magnetic body portion of the mover is a cylindrical portion, and the locking body is fitted and coupled to the cylindrical portion,
The diameter of the outer peripheral surface of the cylindrical portion of the mover is constant, and the diameter on the first coil side of the inner peripheral surface of the cylindrical portion of the mover is the same as that of the inner peripheral surface of the cylindrical portion of the mover. An electromagnetic driving device for weft insertion control in a loom having a diameter larger than that on the second coil side .

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