JPH0489707A - Flexible shaft for conveyor - Google Patents

Abstract

PURPOSE:To optimize a shaft for a particulate carrier device in a flexible shaft for a conveyor carrying glass bottles and/or the like by winding a resinous cord spirally round a flexible rod provided with a resinous layer having a specific wear loss and a coefficient of dynamic friction on a steel rope. CONSTITUTION:A resinous layer 12 having 5X10-<4>mm<3>/kg.m or less of a specific wear loss and 1.0 or less of a coefficient of dynamic friction is arranged on a steel rope 11 so as to form a flexible rod 1. Then, a resinous cord 2 consisting of polyolefine and/or the like is wound spirally round the flexible rod 1. Here, super high molecular weight polyethylene and/or the like is used as resin for forming a resinous layer 12 so that the wall thickness can be set not more than 2.0mm. A winding pitch of the resinous code 2 is determined by the number of containers as well as the size thereof and the number of revolutions of a shaft.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a device for conveying containers such as glass or plastic bottles, or devices for conveying containers such as coal, ore, grains, wood chips, plastic chips, cement, resin pellets, etc. This invention relates to a flexible shaft for a conveyor used in a device for conveying powder and granular materials.

[Prior art/problems to be solved by the invention] A steel cable (wire rope) is used to transport containers such as glass or plastic bottles (hereinafter simply referred to as containers) filled with liquid or the like. A shaft made of steel or other metal wire is used. A container conveying device using a shaft with this type of structure arranges the shafts in parallel at regular intervals, suspends the container between the shafts, and usually hooks the flange on the neck of the container onto the shaft), and rotates the shaft. The container is configured to transport the container.

This device uses a transport principle that is completely different from the normal belt conveyor or roller conveyor used to transport containers. In other words, it moves containers by friction between the shaft and the neck of the container. Positioning is accurate, manufacturing process lines can be automated, and the structure of the device itself is simple and compact, and equipment costs are low.

In the above-mentioned device, the containers are conveyed by the high-speed rotation of the shaft, so the container suspended on the shaft, especially the neck (including the collar) of the container that comes into contact with the shaft, should be protected from wear and damage as much as possible, and the shaft should be The shaft is required to have as few structural defects as possible so that rotational torque can be efficiently transmitted and containers can be conveyed smoothly.

By the way, the above-mentioned shaft is usually made by coating a steel cable with a resin, and winding a steel wire in a spiral shape on the resin layer. During transportation of the above device, the container slides not only on the coil but also on the resin layer of the shaft, and eventually the coil is worn out and the resin layer in the portion in contact with the container is also worn out. Therefore, the shaft must be replaced periodically, but it is important to extend the life of the shaft in order to reduce maintenance costs. Also, since the shaft rotates at high speed,
If there is eccentricity, waviness (that is, meandering) is likely to occur during rotation, which may impede container transportation.

On the other hand, one method for transporting granular materials such as coal, ore, grain, wood chips, plastic chips, cement, and resin pellets is to insert a coiled wire, often made of steel, into a metal or resin tube. There is a method in which a steel wire is rotated to convey powder and granules introduced from an inlet provided at one end of the tube to an outlet provided at the other end.

However, the coiled wire does not transport the powder smoothly, and some powder remains in the tube, making the amount of powder discharged from the other end of the tube unstable.

Further, in transportation using such a coiled wire, the conveying line may be inclined to transport the powder from the lower end to the upper end of the tube, but it also has the disadvantage that the lifting force to carry the powder upward is small.

Therefore, an object of the present invention is to provide a flexible shaft for a conveyor that is most suitable not only for the container conveying apparatus described above but also for a powder conveying apparatus.

[Means to solve the problem]

The objective is to achieve a specific wear amount of 5 x 10-' (mm3/
kg - m) or less and a dynamic friction coefficient of 1.0 or less, a flexible rod is provided with a resin layer on a steel cable, and a resin cord is spirally wound around a rond. Achieved by a flexible shaft.

With the above configuration, the flexible shaft of the present invention reduces the amount of frictional heat generated due to sliding with the container in the container conveyance device. In particular, the amount of frictional heat generated by the bending rotation of the shaft and the sliding movement with the container at the curved portion of the curved conveyance line is significantly reduced. This makes it possible to extend the life of the shaft.

The flexible shaft of the present invention has sufficient rigidity to not bend due to rotation and to sufficiently transmit rotational torque applied from one end of the shaft to the other end, and flexibility so that it can be easily installed along a curved conveyance line. It is important to have both. However, in the present invention, when selecting a steel cable material having both flexibility and rigidity, the following points should be kept in mind.

That is, in a container conveying device as shown in FIGS. 3 to 5, in which the shaft is used, the shaft is locked to a rail (generally having a main body and a shelf protruding from the main body). If the shaft is rotated, there is a risk that the shaft may come off the rail, so the rail is usually provided with suction means for suctioning the shaft to the rail. Therefore, for example, when a magnet or a magnetic material is used as the attraction means, the steel cables are made of several (or tens of) steel cables made of magnetic metals such as steel, nickel, cobalt, and alloys thereof, so that the steel cables are attracted by magnetic force. It is preferable to have a structure in which several strands are further twisted on top of a strand in which several strands are twisted together. Regarding this steel rope structure, the wire rope is twisted in normal twist, rung twist, and S twist, which is the direction of twist.
There are no particular limitations on the Z twist.

Since the resin layer provided on the steel cable slides at high speed in direct contact with the neck and collar of the container, it is required to have excellent wear resistance and low contact resistance.

Therefore, in the present invention, the resin layer is made of a resin material whose specific wear amount and coefficient of dynamic friction are both below specific values. The specific wear amount is 5X under the conditions that the surface pressure is 3 kg/afl, the sliding speed (peripheral speed) is 33.3 m/min, the mating material is stainless steel (SUS304), and the sliding test time is 168 hours. 10-'mm''/kg-m or less, preferably 5 X l O-'mm'/kg-m or less.

The coefficient of dynamic friction is determined when the surface roughness (Rz) of the mating material is 6.
μm steel, and here it mainly refers to the sliding friction coefficient, where the surface pressure is 7.5 kg/c+fl and the sliding speed is 1.
Under the condition of 2 m/min, it is sufficient that it is 1.0 or less, preferably 0.5 or less.

The present invention does not specify any resin material as long as it satisfies the requirements for the specific wear amount and dynamic friction coefficient. Examples include submer manufactured by Mitsui Petrochemical Industries, Ltd., ultra-high molecular weight polyethylene, polyoxymethylene (polyacetal), polyamide (nylon) 6, and the like. Among these, Lubmar is preferred in terms of sliding resistance and durability.

The resin layer may be provided using a conventional extrusion coating technique. For example, a method is shown in which a resin material is melted and extruded from a die placed on the axis in the traveling direction of the steel cable while the steel cable is fed in one direction under constant tension, and simultaneously coated onto the steel cable.

Further, the thickness of the resin layer depends on the use and size of the shaft, but is usually 2.0 mm or less, preferably 1.0 mm or less. It is desirable that this wall thickness be as uniform as possible in order to improve the concentricity of the shaft. Specifically, when the thickness of the resin layer is t, the value of (1 (maximum) t (minimum))/l should be 0.1 or less, preferably 0.05 or less.A shaft that satisfies this numerical condition can be rotated at even higher speeds.

The resin cord is helically wound around the flexible rod made of the above-mentioned steel cable and resin layer, but the resin that is the material of the cord is not particularly limited. However, since containers are transported by rotation of the shaft in the container transport device for which the shaft is used, it is important for product and safety reasons that the neck (including the collar) of the container, which the cord comes into direct contact with, is not worn out or damaged. It is. In particular, with containers filled with carbonated beverages, greater care must be taken to prevent damage to the container. Therefore, the cord has good abrasion resistance, flexibility, rolling and sliding properties, and dynamic friction (
It is preferable that the coefficients (sliding friction and rolling friction) are small. In addition, a separate powder and granular material conveying device can transport powder and granular materials (e.g. gravel, crushed stone, coal, coke, iron ore, soil, limestone,
Since so-called bulk materials such as grain, cement, wood and resin chips and pellets are transported by the rotation of the shaft, it is desirable that the cord has sufficient abrasion resistance and strength to correspond to the rotation of the shaft.

As the resin material for the cord having the above characteristics, polyolefin (for example, Mitsui Petrochemical Industries Ltd.'s Submer, etc.) is used.
, polyether (e.g. polyacetal, polyphenylene ether, etc.), polyamide (e.g. 6-nylon,
6,6 nylon, 11 nylon, etc.), polyalkylene (e.g. polyethylene, especially ultra-high molecular weight polyethylene,
Examples thereof include polypropylene, etc.), fluororesins (e.g., polytetrafluoroethylene, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymers, etc.), and polyesters (e.g., polyethylene terephthalate, polybutylene terephthalate, etc.). Among these, trunbumer or ultra-high molecular weight polyethylene is most suitable, mainly considering sliding properties and durability.

The entire cord may be made of the resin mentioned above, but it can be made of Kevlar glass,
It may have a core made of carbon fiber or the like. A cord with a core is advantageous in that it is possible to suppress cord elongation due to temperature rise due to frictional heat, tensile load, etc., and as a result, disturbances in the pitch of the spirally wound cord can be prevented.

In addition, the pitch is determined based on the size of the container, the number of containers to be transported, the shaft rotation speed, etc. after taking into account the conveyance speed of the container in the case of a container conveyance device, and the pitch is determined based on the type and size of the powder and granule in the case of a powder conveyance device. It will be determined as appropriate based on the following. Also, the pitch need not be constant over the entire length of the shaft, but may vary, for example, at any part of the shaft.

〔Example〕

EMBODIMENT OF THE INVENTION Hereinafter, the flexible shaft for conveyors of this invention is demonstrated in detail based on an Example.

FIG. 1 shows an example of the shaft, and FIG. 2 shows its cross section. This shaft consists of a flexible rod 1 and a resin cord 2 spirally wound around the rod 1. The rod 1 is provided with a resin layer 12 having a specific wear amount and a dynamic friction coefficient of the above-described specific values on a steel cable 11, and the cord 2 has a core body 21 at the center of the resin layer 22.

Next, the case where the flexible shaft of the present invention is used in a container conveyance device will be outlined. In FIG. 3 showing a general plan view of the entire container conveyance device, two rails 101.102 each having a total length of 3 m are arranged in parallel at regular intervals in a substantially right-angled curved shape with a radius of curvature of 500 mm.
02, permanent magnets 103 are buried at regular intervals (for example, 200 mm). Although not shown in detail in the drawing, the flexible shaft 1 is
04.105 are respectively attracted and locked to rails 101.102, and one end of each shaft 104.105 is attached to a bearing 106.105.
107, and the other end is rotatably supported by another bearing 108.

Bearing 10B is connected to motor 109 and shaft 104
．． 105 can be rotated in opposite directions.

Note that the bearing 108 may have a transmission so that the rotational speed transmitted to the shirts 104 and 105 can be adjusted.

In such an apparatus, a container (not shown in FIG. 3) is suspended between shafts 104.105.
105 in the directions of the arrows, the container is moved in one direction (in the figure, in the direction of the bearing 108).

This container conveying device will be explained in more detail with reference to FIGS. 4 and 5. 4 is a perspective view taken along line AA' in FIG. 3, and FIG. 5 is a sectional view taken along line AA'. The rail 102 (the rail 101 is omitted in FIG. 4) has a stainless steel rectangular main body 121 and a shelf 122 protruding from the main body 121, and the rail as a whole has an L-shape. Similarly, the rail 101 is connected to the main body 1.
11 and a shelf 112. Both rails 101 and 102 are supported at regular intervals by support arms 110 (the rail 101 side is not shown in FIG. 4) so that the shelf portions 112 and 122 face each other.

Rectangular permanent magnets 103 are embedded in the main body part 111.121 at regular intervals, and shelf parts 112.122
A flexible shaft 104, 105 is placed on top, respectively. Each shirt) 104.105 is rail 101
．． It is attracted to the side surface of the main body part 111.121 by a permanent magnet 103 so as not to come off from the main body part 111.121 and the shelf part 112.122. Therefore, the rail 101. of the shaft 104.105.
It can be easily attached to and detached from 102.

The shaft 104, 105 has a structure as shown in FIGS. 1 and 2, that is, it consists of a flexible rod 141, 151 and a resin cord 142, 152 spirally wound around the rod. The winding direction is exactly opposite. shaft 1
04.105 motor 109 on rail 101.102
(See FIG. 3) allows rotation in mutually opposite directions as indicated by the arrows.

In such an apparatus, as is clear from FIG. 5, when the collar 201 on the neck of the container 200 made of polyethylene terephthalate is hooked to the shaft 104, 105 and the container 200 is suspended between the shafts 104, 105 (
When suspending, the container can be easily hung between the shafts 104.105 by slightly increasing the distance between the shafts 104.105 at one end.
As the container 105 rotates, the container 200 is transported in the direction of arrow A. That is, the container 200 is pushed in the direction of arrow A by the cords 142, 152 of the shafts 104, 105, and is translated one after another.

Here, a specific example of the size of the shaft used in the above-mentioned container conveyance device is as follows: the diameter of the neck of the container is 26.0 mm, the diameter of the collar is 4.
1.2 mm, and its wall thickness is 3.35 mm, the diameter of the rondo is 7.0 m, the diameter of the steel cable is 6.0 mm, the thickness of the resin layer on the steel cable is 0.5 mm, the diameter of the cord is 4.0 an, Core diameter 1.01
I11, the thickness of the resin layer of the cord is 1.5 mm.

In addition, the cord pitch is 38mm, and the shaft flight diameter is 15mm.
, 0 an.

By using the shaft of the present invention in the container conveying device as described above, the resin layer of the Rondo has a specific amount of specific wear and a coefficient of kinetic friction, so the amount of frictional heat generated with the neck of the container is reduced, and the shaft has a long lifespan. will be extended. In particular, generation of frictional heat at the curved portion of a curved line as shown in FIG. 3 is significant, but this can be considerably suppressed with the shaft of the present invention. Furthermore,
Based on the thickness of the resin layer described above, [L (maximum) t
(Minimum)] By setting the value of /l below 0.1, the concentricity increases, and even if the attraction force of the magnet embedded in the rail is low, the shaft will be reliably locked to the rail, making it possible to use an inexpensive magnet. can be adopted, and equipment cost reduction can be achieved.

Next, a case will be described in which the flexible shaft of the present invention is used in a powder transport device. The overall structure of the conveying device is almost the same as that conventionally known, only using a shaft instead of a corded wire, so the description will focus on the state of transportation of the powder and granular material.

FIG. 6 shows a vertical cross section during transport of powder and granular material, and shows a tube 180 made of metal (stainless steel, etc.) or resin (plastic, nylon, polyacecool, ultra-high molecular weight polyethylene, etc.), which may have a steel cable and a resin layer. flexible rod 17
1 and a resin cord 172 is inserted and arranged along the central axis of the tube. One end of the shaft 170 is connected to a motor (not shown), and the other end is rotatably supported by a bearing or the like. A granular material 190 exists in the gap between the shaft 170 and the tube 180, and the granular material 190 is supplied from an inlet provided on the motor side of the tube 180 and discharged from an outlet provided on the bearing side. It is composed of In such a conveying device, when the shaft 170 is rotated by the motor in the direction of the arrow, the powder 190 is pushed by the cord 172 and is conveyed in the convex direction of the arrow.

Although the conveyance line in FIG. 6 is a straight line, the amount of powder 190 discharged from the discharge port of the tube 180 is stable even on a curved line or an upward line. Further, since the shaft 170 has a large lifting force on the powder and granular material 190, the amount of transportation is constant even when applied to an uphill route in particular.

Examples 1 to 4, Comparative Examples 1 to 3, and Experimental Example 10 Shafts of the following sizes were manufactured using resin materials for the resin layers and cords as shown in Table 1.

The diameter of the rod is 7.0mm, the diameter of the steel cable is 6.0cm,
The thickness of the resin layer is 0.5#, the diameter of the cord is 3. Otr
tm, core diameter 1.0 stroke, cord resin layer thickness 1.0
mm.

Shaft flight diameter 13, cord winding pitch 35
It is mm. This was used in the container conveying device shown in Figures 3 to 5, and the durability (degree of wear) of the shaft and damage (or degree of wear) to the neck of the container were examined using the test method 1Lii) below, and the results are displayed. Shown in 1.

The container has a neck diameter of 26.0 mm, a collar diameter of 41.2 mm, and a wall thickness of 3.35 mm. Moreover, the steel cable structures are all the same.

i) Shaft durability test method Shaft rotation speed 100 Or, p, m, Container conveyance speed 60m/min, Container conveyance pitch 120mm, Container weight 2k
After operating for 15 hours under the condition of
g−m). If the weight change of the rod and cord per shaft length of 120 mm is 1×10 4 g or less, the practical durability is determined to be “good”, and if it is larger than that, it is determined to be “’poor”.

11) Test method for examining the degree of damage to the neck of the container After the operation time was 90 seconds and the other conditions were the same as in the durability test above, the neck of the polyethylene terephthalate container was visually inspected to the extent that it would damage the product value. It is determined whether or not scratches occur, and if such scratches occur, it is determined to be "good", and if not, it is determined to be "bad".

(The following is a blank space) [Effects of the Invention] As explained above, the flexible shaft for a conveyor of the present invention has a resin layer on a steel cable having a specific amount of specific wear and a coefficient of dynamic friction, so it has the following effects. has.

i) The amount of frictional heat generated with the neck of the container is reduced.

In particular, frictional heat on curved conveyance lines is significantly suppressed.

This extends the life of the shaft.

11) Since the concentricity of the shaft is improved by setting the thickness variation value of the resin layer of the rod to the above-mentioned 0.1 or less, high-speed rotation of the - layer is possible. In addition, since a low-cost magnet can be used as the attraction means buried in the rail, the cost of the device can be reduced.

iii) In addition, the powder transport device not only has excellent wear resistance, but also has a stable discharge amount of powder. Moreover, since the lifting force of the granular material is large, the amount of granular material transported is constant, especially on the upward conveyance route.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway perspective view showing an example of the shaft of the present invention, FIG. 2 is a cross-sectional view of the shaft shown in FIG. 1, and FIG. 3 is a schematic plan view of a container conveyance device using the shaft. Fourth
The figure is a partially omitted perspective view taken along line 1-A' in Fig. 3, and Fig. 5 is a partially omitted sectional view taken along line AA' in Fig. 3.
The figure is a partially omitted vertical cross-sectional view of a powder transport device using a shaft. :Flexible rod:Resin cord:Steel cable:Resin layer of rod:Core:Resin layer of cord

Claims (1)

[Claims] A flexible rod on which a resin layer with a specific wear amount of 5×10^-^4 (mm^3/kg・m) or less and a dynamic friction coefficient of 1.0 or less is provided on a steel cable, and a spiral shape on the rod. A flexible conveyor shaft characterized by comprising a resin cord wrapped around the shaft.