Weft detection sensor for weft feeder

Abstract

To provide a weft detection sensor for a weft feeder, which includes an optical element in an inclined state of being inclined to a surface of a substrate, and can suppress a manufacturing cost and a component cost more than before.SOLUTION: A weft detection sensor for a weft feeder includes a light projecting element and a light receiving element as optical elements attached to a substrate, and detects weft on a weft feeder of a loom in such a manner that light projected from the light projecting element is reflected by a reflection plate and is received by the light receiving element. In the weft detection sensor for the weft feeder in which at least one of the light projecting element and the light receiving element is an inclined optical element that is disposed in an inclined state of being inclined to a surface of the substrate, the light projecting element or the light receiving element is a surface-mounted optical element, is an inclination member which is interposed between the inclined optical element and the substrate, and is used for bringing the inclined optical element into the inclined state of being inclined to the substrate.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a weft detection sensor for a weft feeder, which includes a light-emitting element and a light-receiving element as optical elements attached to a substrate, and detects a weft on the weft feeder of a loom by light emitted from the light-emitting element being reflected by a reflector and received by the light-receiving element, and in which at least one of the light-emitting element and the light-receiving element is an inclined optical element that is provided in an inclined state with respect to the surface of the substrate. [Background technology]

[0002] It is known that a weft detection sensor is provided in a weft feeder provided in a loom for storing a weft to be inserted. The weft detection sensor includes a light-emitting element and a light-receiving element as optical elements. The weft detection sensor detects the weft on the weft feeder by light emitted from the light-emitting element, which is reflected by a reflector and received by the light-receiving element.

[0003] In recent general weft detection sensors, the light-emitting element and the light-receiving element are attached to a substrate. In some weft detection sensors, at least one of the light-emitting element and the light-receiving element is provided in an inclined state with respect to the surface of the substrate in order to increase the amount of light received by the light-receiving element (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Microfilm of Utility Model Application No. 61-101829 (Utility Model Application No. 63-011585) [Patent Document 2] Japanese Patent Publication No. 2020-041251 Summary of the Invention [Problem to be solved by the invention]

[0005] In the conventional weft detection sensor, when the optical element is attached in the inclined state to the substrate, an optical element with lead wires is generally used as the optical element.

[0006] To achieve the tilted state of the optical element, it is necessary to tilt the optical element attached to the substrate by soldering on the lead wires and maintain the tilted state, and a member is used to maintain the tilted state.

[0007] Furthermore, in conventional weft detection sensors that include an optical element that is tilted as described above, the installation of the optical element and the above components is time-consuming, which results in high manufacturing and component costs.

[0008] Incidentally, Patent Document 2 discloses that a surface-mounted optical element is used in a weft detection sensor of a weft feeder, instead of an optical element with lead wires. However, a surface-mounted optical element is usually mounted on a substrate without being inclined relative to the surface of the substrate, and Patent Document 2 only discloses such a configuration.

[0009] The present invention has been created in consideration of the above-mentioned circumstances, and aims to provide a weft detection sensor for a weft feeder that includes an optical element that is inclined as described above, and that can reduce manufacturing and component costs compared to conventional methods. [Means for solving the problem]

[0010] The present invention is based on a weft detection sensor for a weft feeder, which includes a light-emitting element and a light-receiving element as optical elements attached to a substrate, and detects a weft on the weft feeder of a loom by light emitted from the light-emitting element being reflected by a reflector and received by the light-receiving element, and in which at least one of the light-emitting element and the light-receiving element is an inclined optical element that is arranged in an inclined state with respect to the surface of the substrate.

[0011] The weft detection sensor for a weft feeder of the present invention is characterized in that the light-emitting element and the light-receiving element are surface-mounted optical elements, and the sensor is provided with a tilting member interposed between the tilting optical element and the substrate, for tilting the tilting optical element relative to the substrate. [Effects of the Invention]

[0012] According to the present invention, a surface-mounted optical element is employed as the optical element, and a tilting member is interposed between the optical element and the substrate, thereby realizing the tilted state of the optical element. Since the tilting member is a simple component that can be interposed between the surface-mounted optical element and the substrate, the present invention makes it possible to reduce the cost of the weft detection sensor compared to conventional ones.

[0013] Furthermore, since the inclined state can be easily achieved by simply attaching the inclined member to the base plate so as to be interposed as described above, according to the present invention, the weft detection sensor can be manufactured at a lower cost than conventional ones. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a side view showing a weft feeder to which a weft detection sensor according to the present invention is applied; [Figure 2] FIG. 2 is a cross-sectional view of the weft feeder shown in FIG. 1 taken along line AA. [Figure 3]FIG. 3 is an enlarged view of a weft detection sensor (unwinding sensor) portion in FIG. 2. [Figure 4] 10A and 10B are enlarged views of the portion of the substrate surface where the tilting optical element is attached, where (a) is a plan view when the light-emitting element is not attached, (b) is a plan view when the light-emitting element is attached, and (c) is a cross-sectional view along line BB. [Figure 5] 10A and 10B are enlarged views showing another example of the configuration of the inclined member, where (a) is a plan view and (b) is a cross-sectional view taken along line CC. [Figure 6] 10A and 10B are enlarged views showing another example of the configuration of the tilting member, where (a) is a plan view and (b) is a cross-sectional view taken along line DD. DETAILED DESCRIPTION OF THE INVENTION

[0015] 1 and 2 show an example of a weft feeder to which the present invention is applied. In this embodiment, the weft detection sensor is an unwinding sensor 1 for detecting a weft unwound from the weft feeder.

[0016] In addition, the weft feeder 100 in this embodiment is equipped with the unwinding sensor 1, a storage drum 101 that stores the weft Y in a wound state, a weft guide 102 that rotates along the outer surface of the storage drum 101 to wind the weft Y around the storage drum 101, a drive motor 103 that rotates the weft guide 102, and a locking pin 104 that is arranged to be able to move forward and backward relative to the outer surface of the storage drum 101.

[0017] The storage drum 101 has a shape like a cylinder divided into four circumferentially, and the weft yarn Y is wound around its outer peripheral surface. The drive motor 103 is disposed behind the storage drum 101 (on the right side in FIG. 1). The weft guide 102 is tubular, and its front end (on the left side in FIG. 1) is located near the outer peripheral surface of the storage drum 101. The weft guide 102 is driven by the drive motor 103 to rotate around the storage drum 101. A yarn passage (not shown) is formed in the shaft center of the drive motor 103, and the weft guide 102 is connected to the yarn passage. The weft yarn Y is supplied from the rear side of the drive motor 103, passed through the yarn passage to the front end of the weft guide 102, and wound around the storage drum 101 by the rotation of the weft guide 102. It is then passed through the storage drum 101 and passed through a weft insertion nozzle (not shown).

[0018] The locking pin 104 is located above the storage drum 101 and is driven vertically by a solenoid (not shown) so that its tip can be switched between a locking position in which it contacts the outer peripheral surface of the storage drum 101 and an unwinding position in which it is separated from the outer peripheral surface of the storage drum 101. The solenoid is built into (supported by) a support block 105 located above the storage drum 101, and the support block 105 is supported by the drive motor 103 via a support bracket 106.

[0019] 2 and 3, the unwinding sensors 1 are provided at two locations, one on the left and one on the right of the locking pin 104 (left and right in FIG. 2), depending on the rotation direction of the weft guide 102. Each unwinding sensor 1, 1 is located downstream of the locking pin 104, and the counterclockwise unwinding sensor 1 corresponding to the counterclockwise rotation (arrow L) of the weft guide 102 is provided on the right side of the locking pin 104, and the clockwise unwinding sensor 1 corresponding to the clockwise rotation (arrow R) of the weft guide 102 is provided on the left side of the locking pin 104. The counterclockwise unwinding sensor 1 and the clockwise unwinding sensor 1 have the same configuration, which is symmetrical on the left and right, and therefore the following description will be based on the counterclockwise unwinding sensor 1.

[0020] The unwinding sensor 1 includes two optical elements, a light-emitting element 3 and a light-receiving element 4, a substrate 2 on which both optical elements are attached, and a reflector 5 for reflecting the projection light B1 emitted from the light-emitting element 3. In this embodiment, both the light-emitting element 3 and the light-receiving element 4 are inclined optical elements that are provided in an inclined state with respect to the substrate 2.

[0021] Furthermore, the substrate 2 is supported in a horizontal position inside a storage space 107 formed as an opening on the lower surface of the support block 105. The light-emitting element 3 and the light-receiving element 4 will be described in detail later, but these two optical elements are provided at an inclination relative to the surface (lower surface) of the substrate 2. The reflector 5 is provided in a manner embedded in the outer peripheral surface of the storage drum 101 at an inclination relative to the substrate 2. A dust cover 108 made of a transparent plate is attached to the opening of the storage space 107.

[0022] According to this unwinding sensor 1, the projected light B1 projected from the light-projecting element 3 is reflected by the reflector 5, and the reflected light B2 is received by the light-receiving element 4. Then, when the weft yarn Y unwound from the storage drum 101 crosses the paths of the projected light B1 and the reflected light B2, the amount of reflected light B2 received by the light-receiving element 4 changes, and the weft yarn Y is detected based on the change in the amount of light.

[0023] In the unwinding sensor (weft detection sensor) 1 for the weft feeder 100 described above, in the present invention, the light emitting element 3 and the light receiving element 4 are surface-mounted optical elements 3, 4.

[0024] The unwinding sensor (weft detection sensor) 1 is provided with a tilting member 6 interposed between the tilting optical elements 3, 4 and the substrate 2, for tilting the tilting optical elements 3, 4 relative to the substrate 2.

[0025] In this embodiment, the light-emitting element 3 and the light-receiving element 4, which are provided as tilted optical elements 3 and 4, have basically the same configuration for arranging them in an inclined state relative to the substrate 2. Therefore, below, we will specifically explain the configuration for arranging the light-emitting element 3 in an inclined state relative to the substrate 2 for the light-emitting element 3 of the two.

[0026] Fig. 4 shows an enlarged view of a portion where the light-projecting element 3, which is an inclined optical element 3, is attached on the surface of the substrate 2. In the actual unwinding sensor (weft detection sensor) 1, the light-projecting element 3 is provided on the lower surface of the substrate 2, but here, the description will be based on the orientation where the light-projecting element 3 is located on the upper side of the substrate 2, as shown in Fig. 4(c).

[0027] 4(b) and 4(c), the light-projecting element 3 has a generally rectangular parallelepiped shape with rectangular upper and lower surfaces. The light-projecting element 3 has a light-emitting portion 31 that is exposed on its upper surface and emits light. The light-projecting element 3 also has electrodes 32, 32 at both ends for applying electricity to the light-projecting portion 31. The light-projecting element 3 is attached to the substrate 2 on its lower surface, with its short sides inclined relative to the substrate 2 (details will be described later).

[0028] 4(a) shows the surface of the substrate 2 in a state where the light-projecting element 3 is not attached. In FIG. 4(a), the rectangular portion indicated by the two-dot chain line is an area (hereinafter referred to as "existence area S") where the light-projecting element 3 is assumed to exist in a plan view when the light-projecting element 3 is attached to the substrate 2 in the tilted state (details of which will be described later) in this embodiment.

[0029] Note that the size of the rectangular existence area S in the direction of its long side (hereinafter referred to as the "length direction") naturally coincides with the size of the long side on the upper surface (lower surface) of the light-projecting element 3. On the other hand, the size of the short side (hereinafter referred to as the "width direction") is slightly larger than the size of the short side on the upper surface (lower surface) of the light-projecting element 3 in the illustrated example, because the light-projecting element 3 is attached in the inclined state.

[0030] A tilting member 6 is provided on the surface of the substrate 2 to tilt the light-emitting element 3 with respect to the substrate 2. In this embodiment, a pair of tilting members 6 are provided, as shown in FIG.

[0031] Incidentally, the tilting member 6 may be a member made specifically for that purpose, but it is also possible to use a circuit element (for example, a resistor) used in a general electronic circuit as the tilting member 6. By using such a circuit element, the cost of making a dedicated member is eliminated, and it is possible to keep the manufacturing cost of the weft detection sensor low.

[0032] In the illustrated example, each of the tilting members 6, 6 is a plate-shaped member whose end face forms a narrow (long, thin) rectangle. Each of the tilting members 6, 6 is disposed on the substrate 2 so that the direction of the long side of its end face coincides with the width direction and that a portion of the tilting member overlaps with the existence region S. The arrangement of each of the tilting members 6, 6 in the width direction is determined in relation to its thickness t and the tilt state of the light-projecting element 3, as will be described later. The pair of tilting members 6, 6 is disposed symmetrically with respect to the center of the existence region S in the length direction.

[0033] In addition, on the substrate 2 on which the inclined member 6 is provided, a pair of electrode pads 21, 21 (copper foil) are provided for electrically connecting the light-emitting element 3 (electrode 32) to the electronic circuit on the substrate 2 (Figure 4(a)).

[0034] Each of the electrode pads 21 is a thin plate formed in a substantially rectangular shape. The size of each of the electrode pads 21 in the short side direction is smaller than the size of the presence region S in the length direction. In the illustrated example, the size of each of the electrode pads 21 in the long side direction is smaller than the dimension of the presence region S in the width direction and is larger than half of that dimension.

[0035] The electrode pads 21, 21 are arranged such that their long sides coincide with the width direction and overlap with the presence region S on both sides in the length direction of the presence region S. Each electrode pad 21, 21 is arranged such that about half of its short sides overlap with the presence region S. Furthermore, each electrode pad 21, 21 is arranged such that the position of one of its short sides in the width direction coincides with the edge of the presence region S on the side opposite to the side where the inclined member 6 overlaps. As a result, the electrode pads 21, 21 are arranged symmetrically with respect to the center of the presence region S in the length direction, with a gap between them in the length direction, within the range of the presence region S in the width direction.

[0036] The size of each electrode pad 21, 21 in the width direction is such that, when provided as described above, it overlaps with the tilting member 6 in the width direction. Each electrode pad 21, 21 has a chamfered corner located on the existence region S and facing the tilting member 6. The chamfered area in the width direction is slightly larger than the overlapping area with the tilting member 6, as described above. This makes the gap between the electrode pads 21, 21 in the length direction wider in the chamfered area than in other areas. As a result, the tilting members 6, 6 can be disposed on the substrate 2 with a wider gap between them in the length direction. Therefore, when attaching the light-projecting element 3 to the substrate 2 as described below, the light-projecting element 3 can be placed on the substrate 2 in a more stable state.

[0037] Furthermore, in this embodiment, a circular pad (positioning mark 22) is provided on the substrate 2 as a marker to enable confirmation of the installation position when attaching the light-emitting element 3 to the substrate 2 (Figure 4(a)).

[0038] In the illustrated example, two positioning marks 22 are provided, one on each side of the inclined members 6, 6 in the length direction. Furthermore, the position of each positioning mark 22, 22 is such that, in the width direction, the center thereof is located on the edge of the existence region S on the side that overlaps with the inclined members 6, 6. Furthermore, in the length direction, the edge of each positioning mark 22, 22 on the opposite side to the inclined member 6 side is located on the edge of the existence region S in the length direction. Thus, by positioning the light-projecting element 3 using each positioning mark 22, 22 as a guide, the light-projecting element 3 in the inclined state is positioned in the existence region S.

[0039] Then, the light emitting element 3 is attached to the substrate 2 on which the inclined member 6, the electrode pad 21, and the positioning mark 22 are provided as described above.

[0040] More specifically, first, the light-projecting element 3 is placed on the substrate 2 at a position where it rests on both electrode pads 21 and both tilting members 6. In this state, the light-projecting element 3 is inclined so that one of the two long sides on its underside is in contact with the substrate 2 and the other long side (part) is located above the two tilting members 6. In addition, the light-projecting element 3 and the tilting member 6 are in a state where the underside of the light-projecting element 3 is in contact with the short side of the two short sides on the upper surface of the tilting member 6 that is located within the existence region S.

[0041] Then, the light-projecting element 3 is positioned using the positioning marks 22, 22 as guides. For this positioning, for example, first, the positions of both short sides of the light-projecting element 3 in the length direction are aligned with the opposite edges of both positioning marks 22, 22. Then, in the width direction, the other long side as seen in a plan view on the underside of the light-projecting element 3 is positioned at the center of both positioning marks 22, 22. Incidentally, when the light-projecting element 3 is positioned in this manner, the two positioning marks 22, 22 appear to be semicircular with the same shape, as shown in FIG. 4(b).

[0042] By positioning in this manner, the light-projecting element 3 is positioned in the existence region S in the desired tilted state. Then, by joining the electrodes 32, 32 of the light-projecting element 3 to the corresponding electrode pads 21, 21 by soldering (solder 33, 33), the light-projecting element 3 is attached to the substrate 2 in the tilted state.

[0043] Regarding the inclined state of the light-projecting element 3, when the thickness dimension t of the inclination member 6 is determined, for example, if the thickness dimension t of the inclination member 6 is determined, and the distance from one of the long sides on the underside of the light-projecting element 3 to one of the short sides on the underside of the inclination member 6 that overlaps with the existence region S is d, the inclination (inclination angle) θ of the light-projecting element 3 with respect to the thickness dimension t is determined. The distance d depends on the position of the inclination member 6 in the width direction with respect to the existence region S. Therefore, the position of the inclination member 6 in the width direction is determined in consideration of the thickness dimension of the inclination member 6 so that the light-projecting element 3 is installed at an inclination angle that results in the desired inclined state.

[0044] However, the desired tilt state is the tilt of the light-emitting element 3 relative to the substrate 2 so as to maximize the amount of light received by the light-receiving element 4, and is determined by the relationship between the distance from the top surface of the light-emitting element 3 to the reflector 5 in the unwinding sensor 1, the tilt of the reflector 5 relative to the substrate 2, and the position of the light-emitting element 3 (light-receiving element 4) on the substrate 2.

[0045] In the unwinding sensor 1 for the weft feeder 100 according to this embodiment described above, the surface-mounted optical elements 3, 4 are employed as the optical elements (light-emitting element 3, light-receiving element 4), and the tilting members 6, 6 are interposed between the optical elements 3, 4 and the substrate 2, thereby realizing the tilted state of the optical elements 3, 4. The tilting members 6, 6 are members of a simple shape that can be interposed between the optical elements 3, 4 and the substrate 2, and therefore the cost of the unwinding sensor 1 can be kept lower than that of conventional sensors.

[0046] Moreover, the tilted state can be easily achieved simply by interposing such tilting members 6, 6 between the optical elements 3, 4 and the substrate 2, so the manufacturing costs of the unwinding sensor 1 can be kept lower than those of conventional sensors.

[0047] The present invention is not limited to the examples described above (the above examples), but can also be implemented in modified embodiments such as the following (1) to (5).

[0048] (1) In the above embodiment, the weft detection sensor (unwinding sensor) has both the light-emitting element and the light-receiving element as optical elements, which are inclined optical elements.

[0049] However, the weft detection sensor of the present invention may be one in which only one of the light-emitting element and the light-receiving element is provided as an inclined optical element.

[0050] (2) In the above embodiment, the weft detection sensor (unwinding sensor) has a pair (two) of tilting members provided on the substrate to tilt the optical element.

[0051] However, in the present invention, the number of tilting members is not limited to two as in the above embodiment. For example, the number of tilting members may be three or more, or may be one.

[0052] However, when there is only one tilting member, the size of the tilting member needs to be such that the optical element can be stably placed on the substrate when the optical element is attached to the substrate. Therefore, it is preferable that the tilting member has a size such that the range of its presence in the longitudinal direction when the tilting member is attached to the substrate occupies, for example, about half the size of the presence region in the longitudinal direction.

[0053] (3) In the examples described above, the inclined member is formed as a plate-like member of uniform thickness (with the upper and lower surfaces parallel to each other) as shown in the figure, and accordingly, the weft detection sensor (unwinding sensor) is configured so that the inclined member supports the optical element by abutting the lower surface of the optical element with a line at a corner on the upper surface side of the inclined member that is located within the existence area.

[0054] However, in the present invention, the inclined member is not limited to one formed so that the upper and lower surfaces are parallel to each other. For example, as shown in Fig. 5 (the same components as in the above embodiment are given the same reference numerals), inclined member 6a may be formed so that its upper surface has inclined surface 61a that is inclined relative to the surface of substrate 2 when provided on substrate 2 so as to abut the lower surface of the optical element (the figure shows the case of light-emitting element 3, but the same applies to light-receiving element 4).

[0055] In this case, the tilting member 6a may be configured such that the entire upper surface thereof is the tilted surface 61a, as shown in FIG. 5(b), or may be configured such that only a portion of the upper surface thereof, which is the portion of the upper surface facing the presence region in the width direction, is the tilted surface. Furthermore, the angle (θ' in the example of FIG. 5(b)) of the tilted surface 61a with respect to the lower surface (the surface of the substrate 2) of the tilting member 6a is set to the same angle as the desired tilt angle so that the optical element 3 placed thereon forms the desired tilt angle. When the tilting member 6a is configured in this manner, the tilting member 6a supports the optical element 3 with its surface, thereby allowing the optical element 3 to rest more stably on the substrate 2.

[0056] Incidentally, the shape of the end face of the inclined member (the shape when viewed in the plate thickness direction) is not limited to a rectangular shape as in the above-mentioned embodiment, but may be any shape as long as the range in the longitudinal direction that abuts against the underside of the optical element is large enough (wide enough) to support the optical element in a stable state.

[0057] (4) In the above-described example, the weft detection sensor (unwinding sensor) is configured such that the inclined member is disposed on the surface of the substrate on which the conductor is wired (wiring surface). That is, the surface of the substrate on which the inclined member is disposed is flush with the wiring surface.

[0058] However, in the present invention, the weft detection sensor is not limited to being configured so that the inclined member is installed on the same plane as the wiring surface. For example, as shown in FIG. 6 (where the same components as in the previous embodiment are given the same reference numerals), the weft detection sensor may be configured so that a hole 23 into which the inclined member 6b is embedded (fitted) is formed in the substrate 2, and the inclined member 6b is installed on the substrate 2 by fitting into the hole 23. Note that the example in FIG. 6 is an example of a weft detection sensor configured so that the inclined member 6b has the inclined surface 61b on its upper surface, and the optical element (the figure shows the light-emitting element 3, but the same applies to the light-receiving element 4) is entirely mounted on the inclined member 6b (the entire lower surfaces of the optical elements 3 and 4 abut against the inclined surface 61b). Furthermore, when installing the inclined member on the substrate in an embedded state, the substrate may be formed with a recess (a hole with a bottom) instead of a hole as shown in the figure.

[0059] (5) In the above-described example, the weft detection sensor is an unwinding sensor. However, the weft detection sensor according to the present invention is not limited to an unwinding sensor, and may be, for example, a yarn breakage sensor that detects the occurrence of yarn breakage in the weft feeder (including yarn breakage in the yarn supplier) or a winding amount sensor that detects the amount of weft wound around the storage drum of the weft feeder.

[0060] The present invention is not limited to the above examples and embodiments, and can be modified as appropriate within the scope of the invention. [Explanation of symbols]

[0061] 1 Weft detection sensor (unwinding sensor) 2 boards 3 Light-emitting element (optical element, tilted optical element) 4. Light receiving element (optical element, tilt optical element) 5 Reflector 6, 6a, 6b Inclined members 21 Electrode pads 22 Positioning mark 23 holes 31 Light projector 32 electrodes 33 Solder 61a,61b Slope 100 Weft Feeder 101 Storage drum 102 Weft guide 103 Drive motor 104 Locking pin 105 Support Block 106 Support bracket 107 Containment Space 108 Dust Cover B1 Projection light B2 Reflected light S Existence area Y weft

Claims

[Claim 1] A weft detection sensor for a weft feeder includes a light-emitting element and a light-receiving element as optical elements attached to a substrate, and detects a weft on the weft feeder of a loom by light emitted from the light-emitting element being reflected by a reflector and received by the light-receiving element, wherein at least one of the light-emitting element and the light-receiving element is an inclined optical element provided in an inclined state with respect to a surface of the substrate, The light-emitting element and the light-receiving element are surface-mounted optical elements, and a tilting member is interposed between the tilting optical element and the substrate, for tilting the tilting optical element relative to the substrate. A weft detection sensor for a weft feeder, characterized in that:

Images