JP2000142937A - Structure for detecting meandering of belt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely prevent a crushed component from blocking a light receiving part in a device for detecting meandering of a conveyer belt so as to surely prevent erroneous detection of meandering of the belt. SOLUTION: This structure has a device 5 for detecting meandering of a conveyer belt 2, which is adapted to be applied to a belt type drying and crashing device 1, comprising light emitting parts 51 located at positions which are spaced from both side parts of the conveyer belt 2 by an allowable widthwise distance, and which are above the conveyer belt 2, for irradiating light downward, and light receiving parts 52 arranged at positions below the conveyer belt 3, opposed to the light emitting parts 51, and having light receiving surfaces 53a for receiving light from the light emitting part 51, respectively, and it is constituted so that air from a compressor 56 is blown to the light receiving surfaces 53a of the light receiving parts 52 in particular or in the vicinity thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a belt meandering detection structure attached to a so-called belt-type drying device for drying an object to be dried while being transported by a conveyor belt.

[0002]

2. Description of the Related Art Conventionally, a viscous raw material such as a polymer solution stored in a raw material tank is supplied onto a driving conveyor belt via a raw material supply device located at an upstream end of the conveyor belt. A so-called belt-type drying apparatus is known, in which a drying process is performed on a raw material that sequentially moves by the rotation. In such a belt-type drying apparatus, usually, a plurality of conveyor belts are arranged in a vertical direction, and a crusher for coarsely crushing a dried product is provided at a downstream end of each conveyor belt. Crushes the dried product into coarse products.

[0003] Further, in the belt-type drying apparatus as described above, there is a disadvantage that if the conveyor belt meanders, the defective rate increases. Therefore, in order to avoid such inconvenience, a meandering detection device is provided at the upstream end and / or the downstream end of the conveyor belt. When the meandering detection device detects the meandering of the conveyor belt, the driving of the conveyor belt is temporarily stopped. The belt is stopped, the belt is wrapped around it so that it does not meander, and then restarted.

As the meandering detection device, a so-called photoelectric switch in which a light emitting unit and a light receiving unit are vertically opposed is employed. The light-emitting unit and the light-receiving unit are installed at positions that are separated by an allowable distance from both ends of the conveyor belt, and are installed at vertically opposed positions.

Therefore, when the conveyor belt is rotating at the normal position, the light from the light emitting section reaches the light receiving section to determine that the conveyor belt does not meander. Meandering, the light emitted from the light emitting unit is blocked by the conveyor belt and does not reach the light receiving unit, thereby detecting the meandering of the conveyor belt.

[0006] The meandering detection device as described above is generally provided at the upstream end and / or the downstream end of the conveyor belt. The reason is that the meandering displacement is the largest at the end, so that the meandering can be easily detected.

[0007]

At the downstream end of the conveyor belt, there is provided a crusher for crushing the dried product, and a part of the products crushed by the crusher is provided at the downstream end of the conveyor belt. The main cause is scattering.
The light from the light emitting unit may be blocked. Therefore, in the conventional meandering detection device as described above, the light from the light emitting unit is not blocked by the products or the like scattered even though the conveyor belt does not meander, and does not reach the light receiving unit. There is a problem that it may be determined that the meandering is meandering.

If the meandering detection device erroneously detects meandering even though the conveyor belt is not meandering, the driving of the conveyor belt is automatically stopped. In addition, the quality of the product, such as coloring due to overdrying, occurs once the conveyor belt stops, and the production cost increases accordingly.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is possible to reliably prevent light from a light emitting portion from being blocked by a crushed product or the like. An object of the present invention is to provide a belt meandering detection structure in a belt-type drying device that can reliably prevent erroneous detection.

[0010]

According to the belt meandering detecting structure of the first aspect of the present invention, the raw material supplied to the upstream end of the conveyor belt through the raw material supply device reaches the downstream end around the conveyor belt. In the belt meandering detection structure attached to the belt-type drying device, which is dried by the time it is dried until it is crushed by the crusher at the downstream end, only a permissible distance in the width direction from both ends of the conveyor belt A meandering detection device including a light emitting unit and a light receiving unit disposed at an upper position and a lower position of the separated position is provided, and a light emitting surface of the light emitting unit or a light receiving unit of the light receiving unit disposed at a lower position of the conveyor belt is provided. An air blowing means for blowing air near the surface is provided.

According to this belt meandering detection structure, when the conveyor belt is not meandering and orbiting at a normal position, the light emitted from the light emitting section reaches the light receiving section without being blocked by the conveyor belt. While the conveyor belt detects that the conveyor belt does not meander, if the conveyor belt meanders beyond the allowable range, light from the light emitting unit is blocked by the conveyor belt and does not reach the light receiving unit. Meandering is detected.

The air blowing means blows air near the light receiving surface of the light receiving portion or the light emitting surface of the light emitting portion provided below the conveyor belt of the belt meandering detecting device. Even if a crushed product formed by crushing at the end jumps and falls from the side of the conveyor belt and falls down, it is removed by the blown air and the belt caused by the crushed product etc. Erroneous detection of meandering is reliably prevented.

Therefore, the inconvenience that the conveyor belt is stopped due to the erroneous detection of the meandering of the belt and the production is interrupted to thereby lower the productivity is avoided.

In the belt meandering detecting structure according to a second aspect of the present invention, in the belt meandering detecting structure according to the first aspect, the air blowing means includes an annular air ejection gap surrounding the light receiving portion or the light emitting portion. Leaving and surrounding pipes,
And air supply means for supplying air into the pipe.

According to this belt meandering detection structure, the air from the air blowing means is jetted outward from the upper end of the pipe surrounding the light receiving portion or the light emitting portion. Because it is surrounded by the surroundings, no matter which direction the crushed product that has fallen from the conveyor belt attempts to enter, it is blown off by the blast air, thereby covering the light receiving unit or the light emitting unit with the crushed product. The inconvenience described above can be more reliably prevented.

In the belt meandering detecting structure according to a third aspect of the present invention, in the belt meandering detecting structure according to the first or second aspect, the air supplied to the air blowing means is supplied to the light receiving portion by the discharged air. The wind speed is set so that an obstacle located on the light receiving surface or the light emitting surface of the light emitting section can be blown off.

According to this belt meandering detection structure, an obstacle that has fallen into the space above the light receiving portion or the light emitting portion is reliably blown off by a sufficient wind speed.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an example of a process diagram for manufacturing a product using a belt type drying apparatus to which a belt meandering detection structure according to the present invention is applied. As shown in FIG. 1, the product is manufactured through a storage process P1, a drying process P2, and a crushing process P3. The viscous material M1 as a raw material is stored in the storage tank P11, and the drying step P2 is appropriately driven by driving the pump P12.
To be served.

In the drying step P2, the belt-type drying apparatus 1 to which the present invention is applied is employed. Then, the viscous material M1 from the storage tank P11 is injected into the upstream end of the conveyor belt via the raw material supply device 3 (FIG. 2) in the belt-type drying device 1, and is elongated on the belt surface by the rotation of the conveyor belt. Is formed (hereinafter, referred to as a long product M2). These long products M2 are dried and solidified by a predetermined drying means before reaching the downstream end around the conveyor belt, and solidified in the next pulverizing step P3.
Sent to.

The crushing step P3 is performed by a crusher attached to the downstream end of the conveyor belt. That is, the long product M2 conveyed to the downstream end by the conveyor belt is coarsely crushed (crushed) by a crusher at a position protruding outside from the conveyor belt in the crushing step P3 to be a short product M3 of a predetermined size. .

FIG. 2 is an overall configuration diagram showing an embodiment of the belt-type drying device. As shown in FIG. 2, the belt-type drying device 1 includes a box-shaped housing 11, a plurality of vertically arranged conveyor belts 2 installed in the housing,
A raw material supply device 3 disposed at an upstream end of each conveyor belt 2; a crusher 4 disposed at the downstream end; a belt meandering detection device 5 for detecting meandering of the conveyor belt 2; At the downstream end of the crusher 4 to prevent the short product M3 crushed by the driving of the crusher 4 from jumping and dropping from the side of the conveyor belt 2, thereby preventing the erroneous detection from being performed. And a detection device protection structure 6 for protection.

As shown in FIG. 2, the meandering detecting device 5 includes a pair of light emitting portions 51 in the width direction provided on the upper end of the uppermost conveyor belt 2 on the upstream end side and the downstream end side. And four light-receiving portions 52 provided opposite to the light-emitting portions 51 at a further lower position of the conveyor belt 2. The light emitting unit 51 includes a light source that irradiates light directly downward, while the light receiving unit 52 includes a photoelectric conversion device that excites an electromotive force when irradiated with light. Therefore, by detecting the electromotive force of the photoelectric light emitting element, it is possible to determine that there is no interfering object in the optical path 50 between the light emitting unit 51 and the light receiving unit 52. It is possible to determine that an interference object exists at 50. Note that there is no problem even if the vertical positions of the light emitting unit 51 and the light receiving unit 52 are opposite to the above.

In the present embodiment, the light-emitting portion 51 and the light-receiving portion 52 in the width direction are located at positions where the optical path 50 is separated from the side end of the conveyor belt by an allowable range. Therefore, if any of the plurality of conveyor belts 2 meanders and interferes with the optical path 50, the light from the light emitting unit 51 does not reach the light receiving unit 52, whereby the meandering of the conveyor belt 2 is detected. It has become.

Further, in the present embodiment, at least the light emitting section 51 or the light receiving section 52 provided at the lower position on the downstream side of the attached belt meandering detecting device is configured to be supplied with blast air. This prevents erroneous detection of belt meandering caused by the short article M3 dropped from the conveyor belt 2 blocking the optical path 50. Hereinafter, the air blowing means as an erroneous detection prevention structure will be described using the light receiving unit 52 on the downstream side as an example. FIG. 3 is a partially cutaway perspective view showing an embodiment of the light receiving section 52 on the downstream side.
As shown in this figure, the light receiving portion 52 is a cylindrical light receiver 5 having a light receiving surface 53a of a light receiving element on the upper surface and extending in the vertical direction.
3 and a protective tube 54 into which the light receiver 53 is fitted concentrically.
And a support cylinder 55 that supports the protection cylinder 54 and has the same diameter as the protection cylinder 54, and a compressor 56 that sends compressed air into the protection cylinder 54. The compressor 56 includes a short product M that has fallen on the upper part of the protection cylinder 54.
The ejection capacity is set in advance so that 3 can be blown off.

The light receiving portion 53 is mounted at a central position in the light receiver support member 54a by a light receiver support member 54a having a plurality of support arms projecting from the inner peripheral surface of the protective cylinder 54 toward the center. ing. The upper end of the light receiver 53 projects slightly outside from the upper opening of the protection tube 54, and the short product M3 that has fallen in the housing 11 straddles the upper edge of the light receiver 53 and the upper edge of the protection tube 54. Even if it lands, it slides down due to the inclination between the edges, thereby making it difficult for the short product M3 to stay on the light receiving surface 53a.

According to such an erroneous detection prevention structure, the compressed air is constantly supplied into the protection cylinder 54 by driving the compressor 56, so that the upper edge of the protection cylinder 54 is in contact with the inner peripheral surface of the protection cylinder 54. Air is ejected from an annular gap 534 formed between the light receiving surface 53 and the light receiving surface 5.
3a is surrounded by the jet of air, so that even if the short product M3 falls and tries to land on the light receiving surface 53a, it is blown off by the jet flow and the short product M3 is placed on the light receiving surface 53a. Is deposited and optical path 5
0 can be reliably prevented, thereby making it possible to eliminate erroneous detection in which the belt meandering detection device 5 detects meandering even though the conveyor belt 2 does not meander.

In the present invention, the detection device protection structure 6 is employed as an erroneous detection prevention structure in addition to the air blowing means. This detector protection structure 6
As shown in FIG. 2, a pair of width-preventing plates 61 provided in the downstream direction of the conveyor belt 2 is provided. This fall prevention plate 61 is provided for the upper stage fall prevention plate 6 provided for the conveyor belt 2 of the second or more stages from the bottom.
2 and a lowermost drop prevention plate 63 provided for the lowermost conveyor belt 2.

The upper surface of the fall prevention plate 61 is coated with a coating material made of a material having a small friction coefficient.
As a result, the short product M3 captured by the fall prevention plate 61 is smoothly slid down and returned onto the conveyor belt 2. Examples of the coating material include an adhesive tape made of polytetrafluoroethylene.

As shown in FIG. 2, each of the upper-stage drop prevention plates 62 is parallel to the conveyor belt 2 between the light emitting unit 51 and the crusher 4 and has a lower edge in the width direction of the conveyor belt 2. It is slidably in contact with both ends or opposed to the conveyor belt 2 with a small gap therebetween, and is disposed so as to be inclined such that the upper edge is located outside the conveyor belt 2. Also, the upper-stage fall prevention plate 62 is
The front and rear dimensions are set so that the upstream edge does not interfere with the optical path 50. By providing such an upper-stage fall prevention plate 62 on the downstream end side of the conveyor belt 2 of the uppermost stage to the second stage from the bottom, even if the short-length product M3 scatters, the short-length product M3 is attached to the upper-stage fall prevention plate 62. It will be supplemented and returned on the conveyor belt 2.

As shown in FIG. 2, the lowermost drop-preventing plate 63 has basically the same configuration as the upper-stage drop-preventing plate 62, but has a larger planar shape than the upper-stage drop-preventing plate 62. Dimensions are set. Specifically, the front-rear dimension and the width of the lowermost drop-prevention plate 63 are set to be considerably larger than those of the upper-stage drop-prevention plate 62, whereby the lowermost drop-prevention plate 63 supplements the scattered short product M3. Performance has been greatly improved. However, the lowermost drop prevention plate 63 interferes with the optical path 50 as it is. In order to avoid this interference, in the present embodiment, a light passage hole 63a is formed at a position where the lowermost fall prevention plate 63 interferes with the optical path 50, so that light from the light emitting unit 51 is received by the light receiving unit 52.
To the light receiving surface 53a.

Note that part or all of the upper-stage drop prevention plate 62 may be used as the lowermost-stage drop prevention plate 63, or only the lowermost-stage fall-prevention plate 63 may be used without using the upper-stage drop prevention plate 63. It is also possible to use.

According to the detection device protection structure 6, even if the short product M3 scatters toward the upstream side, the scattered short product M3 is captured by the fall prevention plate 61 provided on each conveyor belt 2. Because it is returned on the conveyor belt 2,
The light path 50 is blocked by the scattered short products M3, and the inconvenience of erroneously detecting that the conveyor belt 2 has meandered even though the conveyor belt 2 does not meander is prevented.

In particular, the lowermost drop prevention plate 63 is
Since the plane size is set to be larger than that of the upper-stage drop prevention plate 62, even if the short product M3 jumps over the upper-stage drop prevention plate 62 and scatters, it is possible to supplement the light path 50 by the short product M3. Can be reliably prevented from being interrupted. Further, the lowermost drop prevention plate 63 is replaced with a short product M3.
By setting the size to be larger than the scattering range, the accumulation of the short product M3 on the lower portion of the housing 11 is reduced,
Maintenance costs can be reduced.

[0034]

According to the belt meandering detection structure of the present invention,
It is possible to reliably prevent erroneous detection of belt meandering caused by scattering of products crushed by the crusher, and to avoid inconvenience of reduced productivity due to production interruption due to erroneous detection.

[Brief description of the drawings]

FIG. 1 is a process diagram of manufacturing a product using a belt-type drying device to which a belt meandering detection structure according to the present invention is applied.

FIG. 2 is a sectional view showing one embodiment of a belt type dryer.

FIG. 3 is a partially cutaway perspective view showing an embodiment of a light receiving section on the downstream side.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Belt type drying device 11 Housing 2 Conveyor belt 3 Raw material supply device 4 Crusher 5 Belt meandering detection device 51 Light emitting part 52 Light receiving part 53 Light receiving device 53a Light receiving surface 54 Protective cylinder 54a Light receiving device support member 55 Support cylinder 56 Compressor 6 Detector Protective structure 61 Fall prevention plate 62 Fall prevention plate for upper stage 63 Fall prevention plate for lowermost stage P1 Storage process P2 Drying process P3 Crushing process M1 Viscous material (raw material) M2 Long product M3 Short product

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Hisashi Ouchi 992, Nishioki, Okihama-shi, Abashi-ku, Himeji-shi, Hyogo Nippon Shokubai Co., Ltd. Nippon Shokubai Co., Ltd. (72) Katsuhiko Harada, inventor 992, Nishioki, Okihama-shi, Aboshi-ku, Himeji-shi, Hyogo 1 F-term in Nippon Shokubai Co., Ltd. (reference) AC59 AC63 AC65 AC76 AC79 AC90 BA36 CA06 DA04 DA06 DA07 DA22 DA25

Claims (3)

[Claims] 1. A method of drying a raw material supplied to an upstream end of a conveyor belt through a raw material supply device before reaching a downstream end around the conveyor belt and crushing the raw material by a crusher at the downstream end. In a belt meandering detection structure attached to a belt-type drying device that makes a crushed product, light-emitting units disposed oppositely at an upper position and a lower position that are separated by an allowable distance in the width direction from both ends of the conveyor belt. A belt meandering detection device, comprising: a meandering detection device comprising: a light-receiving portion disposed below the conveyor belt; and a light blowing portion for blowing air near the light-receiving portion or the light-receiving portion. Construction. 2. The air blowing means comprises a pipe surrounding the light receiving portion or the light emitting portion with an annular air ejection gap left therearound, and air supply means for supplying air into the pipe. The belt meandering detecting structure according to claim 1. 3. The air supplied to the air blowing means is set at a wind speed such that the discharged air can blow off an obstacle located on a light receiving surface of the light receiving portion or a light emitting surface of the light emitting portion. 3. The belt meandering detection structure according to 1 or 2.