JPS6355003B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention measures the length of a belt-like object, particularly a belt-like object such as a tire tread whose cross section parallel to the side edges extending in the longitudinal direction has a substantially parallelogram shape, with high precision while running at high speed. Concerning a measuring device.

Conventionally, a device that continuously measures the length of a tire tread cut to a fixed length on the conveyor line of an extrusion device in the tire manufacturing process has been conventionally used by directly applying a measuring device between the front and rear ends of the tire tread. It has been measured by a measuring means that measures by photoelectric conversion by applying light.

This tire tread is wrapped around the tire carcass on the forming drum of the forming machine and joined in an endless manner.If there is an error in the length of the tread, either long or short, with respect to the outer circumference of the tire carcass, If there is too much or too little in the joint of the tread wrapped around the tread, and the tread is peeled off locally and is too long,
The wire was wrapped slightly slackly, or if it was too short, stretched slightly to ensure that the slopes of the joints matched correctly.

As a result, there has been a problem of uneven tread weight distribution near the joint.

Ride comfort has been rigorously pursued in recent cars, and tire quality is an important factor in ride comfort, so the above-mentioned disparity in tread weight distribution affects the balance and uniformity of product tires. Strict control of the tread length is strongly required since it has considerable negative effects.

By the way, when the tread on the conveyor has a regular cross-sectional shape perpendicular to the longitudinal direction, the lower end which passes the surface through which the belt-shaped object to be measured passes and touches the conveyor surface at the front end and the rear end. A light emitting/receiving device consisting of a light projector and a light receiver, whose optical axis is oriented so as to be blocked by the edge, is installed on the upper and lower sides with an appropriate distance apart, and the front edge, by blocking or exposing the projected light, is installed. If the trailing edge is detected at the same time, the length of the strip can be measured accurately.

However, if the lower surface of the strip in contact with the conveyor surface is not a flat surface, but has a slight curvature in the width direction perpendicular to the longitudinal direction, for example, the tread in the tread extrusion process of tire manufacturing is subject to strong shearing when passing through a die plate. In cases where the lower surface is wavy due to internal stress, the lower edge of the cut surface is not straight but is also wavy. Since the boundary between the slope and the lower edge is unclear, even if the position is detected by photoelectric conversion by shielding or exposing to light, the detection accuracy is low and stable and reliable length measurement cannot be performed. The reality is that improvement measures are desired.

The present invention deals with such a fact, and in particular, measures the longitudinal side length of a strip having a parallelogram-shaped vertical cross section accurately and easily while being transported by a transporting means such as a conveyor. The important objective is to obtain the desired length, and in particular, the length measurement target is the running center line of the expanding belt, and the cross-sectional shape parallel to the longitudinal side edge is approximately a parallelogram. The belt is tilted forward such that its longitudinal side is parallel to the running direction of the belt, and the inclined surface at the front end faces the belt at an acute angle. a photoelectric switch that detects the front end of the band-shaped body mounted on the top and indicates that the band-shaped body has arrived at a predetermined position; a high-speed line sensor camera installed below the running belt of the conveying means so as to be able to receive the light beam reflected from the inclined surface part as a light amount component in the running direction of the belt; a first measuring means for detecting, a floodlight which is spaced rearward from the first measuring means by an offset value slightly shorter than the standard length of the belt, and provided at predetermined positions above and below the belt; a second measuring means having a high-speed line sensor camera; the photoelectric switch detects the front end of the strip and operates the second calculating means at the same time as the photoelectric switch receives a signal emitted; The apparatus further comprises an arithmetic control means for simultaneously measuring the length of a strip existing within the field of view captured by the camera, and calculating the length of the strip by adding these two measured values and the offset value. This is characterized in that, as soon as the photoelectric switch detects the front end portion of the strip, the first measuring means measures the length of the portion existing in front of the portion corresponding to the offset value up to the lower edge of the front end inclined surface portion. As a result of the second measuring means measuring the length of the part existing behind the part corresponding to the offset value up to the lower edge of the rear end inclined surface part, the length of the side part of the belt-like body in contact with the belt surface can be accurately measured. This has led to the achievement of the intended purpose.

An embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

In the figure _, C is a length measuring conveyor in a tire manufacturing tread extrusion line, which is an example of the conveying means according to the _present invention. Although the belts are stretched endlessly between them, the running center line portion where both belts B ₁ and B ₂ are close to each other is kept at an appropriate distance to form a space so that light can pass through. .

A conveyor belt B ₁ is mounted so as to straddle this traveling center line portion, that is, a space portion, with its longitudinal direction parallel to the belt traveling direction, and the belt-shaped body T as a length measurement target is placed so as to straddle this traveling center line portion, that is, the space portion. ，
B ₂ allows this strip T to be conveyed at high speed.

The above-mentioned band-shaped body T is shown as a cutting means (not shown).
The tire tread is cut into a predetermined length by a tire tread, and the shape of the vertical cross section parallel to the side surface extending in the longitudinal direction is approximately a parallelogram with the front end surface and the rear end surface being inclined surfaces, and the inclined surface portion of the front end is Conveyor belts B ₁ and _{B 2} are neatly arranged so as to be tilted forward so that they are facing each other _.
It can be mounted on top.

However, 1 is the conveyor belt of length measuring conveyor C.
This is a light projector that projects light onto the front end inclined surface of the tread T from the gap between B ₁ and B 2. On the other hand, ₂ is a high-speed line sensor camera installed directly below the gap between conveyor belts B ₁ and B ₂ . The light beam reflected from the front end inclined surface portion can be received as a light amount component in the traveling direction of the conveyor C.

The light projector 1 and the high-speed line sensor camera 2 form a first measuring means for photoelectrically detecting the lower edge of the front end inclined surface portion as a boundary between light and darkness.

Reference numerals 3 and 3a denote a projector and a photoelectric switch, such as a photo switch, which detect the front end of the toread T being conveyed on the length measuring conveyor C and issue a length measurement command to the high speed line sensor camera 2. installed at a specific location.

Reference numeral 4 denotes a floodlight, which is provided behind the floodlight 1 with respect to the traveling direction of the conveyor C;
It has a form with an appropriate light projection width in the conveyor traveling direction.

Reference numeral 5 denotes a high-speed line sensor camera that is paired with the projector 4 and is placed above the conveyor C so as to face downward, and is configured to be able to receive the light projected from the projector 4 as a light amount component in the direction in which the conveyor C runs.

The floodlight 4 and the high-speed line sensor camera 5 form a second measuring means, and this measuring means sets its reference point to the first measuring means by an offset value that is slightly shorter than the standard length of the tread T. It is provided so as to be spaced rearward from the reference point of the measuring means, and the rear edge of the tread T is detected as a bright/dark boundary by photoelectric conversion of a digital quantity.

Reference numeral 6 denotes a frame in a moving means for moving the high-speed line sensor camera 5 forward and backward in the direction of travel of the toroid T, and arms 7 ₁ and 7 ₂ on both sides thereof are provided with sliding guides 8 ₁ and 8 ₂ and a screw shaft 9. It is being

Reference numerals 10 ₁ and 10 ₂ are sliding blocks fitted into sliding guides 8 ₁ and 8 ₂ , and the upper surfaces are connected by a mounting plate 11 on which the high-speed line sensor camera 5 is supported and fixed, and one sliding block 10 ₁ is connected to the mounting plate 11 on which the high-speed line sensor camera 5 is supported and fixed. has screw shaft 9
A female thread is provided for threading.

Then, the left side of the screw shaft 9 is rotatably supported on the arm 7 ₂ , and after loosely fitting it into the other sliding block 10 ₂ , it is screwed into the female thread of one sliding block 10 ₁ and the right end is attached to the arm 7 ₁ . The rotary shaft of the drive motor 12 is connected to the rotating shaft of the drive motor 12 attached to the drive motor 12.

Therefore, the rotation of the drive motor 12 causes the sliding blocks 10 ₁ and 10 ₂ to slide together in the direction in which the sliding guides 8 ₁ and 8 ₂ extend, thereby moving the projector 4 and the camera 5. ing.

The series of mechanisms described above moves the second measuring means closer to the first measuring means in the longitudinal direction of the belts B ₁ and B ₂ .
It is formed into a position adjustment mechanism for separating.

Reference numeral 13 denotes a length measuring device spanned between the arms 7 ₁ and 7 ₂ , and 14 is an index attached to the sliding block 10 ₁ that slides on the length measuring device 13 , and this index 14 and the high-speed line The positional relationship with the sensor camera 5 has the following specified conditions.

That is, the reference line of the index 14, for example, the corner line at the right end, is placed perpendicularly above the position of the front end of the field of view (the right end in FIG. 1) when the camera 5 images the upper surfaces of the belts B ₁ and B ₂ . The index 14 and camera 5 are positioned so that they match correctly.

15 is a controller as calculation control means,
When a length measurement command is received from the photo switch 3a, the first measuring means and the second measuring means are operated simultaneously to carry out a measuring operation, and its functions will be explained later in the explanation of the operation.

Next, the measurement operation of the length measuring device configured as described above will be explained.

The tread T, which is extruded into a predetermined cross-sectional shape by an extruder (not shown) and cut into a predetermined length on a conveyor line, enters the conveyor C and is loaded. , and is set at a position that matches the offset value determined through a series of rigorous experiments depending on the type of Toledo T to be extruded.

On the other hand, this offset value is also written and stored in the arithmetic processor of the arithmetic control means 15.

The front end a of the tread T on the conveyor C is the floodlight 3
When the light projected onto the photo switch 3a is blocked,
Since the photo switch 3a issues a length measurement command and activates the controller 15, a signal is sent to each signal processor (not shown) of the high-speed line sensor cameras 2 and 5 to start both the cameras 2 and 5. .

The high-speed line sensor camera 2 detects a clear change in the amount of reflected light at the lower edge b of the torpedo T, and even if this lower edge is slightly curved and floating above the conveyor belts B ₁ and B ₂ , the reflected light The deviation in the change in light amount is minute, and when the camera 2 detects point b, the signal processor causes the calculation section of the controller 14 to start calculation.

On the other hand, the high-speed line sensor camera 5 is
Since the trailing edge C is detected and the detected value is sent to the calculation section of the controller 15 by the signal processor, the controller 1 receives the calculation start signal from the photoelectric switch 3a.
5 calculates the length of the tread T from the previously input offset value of the index 14 and the input from the camera 5 at that time, and outputs this.

As described above, the measuring device of the present invention has a high-resolution high-speed line sensor camera installed close to a relatively long strip T, and measures the offset value of a predetermined dimension rather than the entire length of the strip T. Since the removed partial short and small unit lengths are measured, highly accurate measurements can be made.

Moreover, in the first measuring means, the reflected light from the inclined surface portion is detected by photoelectric conversion using a high-speed line sensor camera, and furthermore, since the high-speed line sensor camera is provided below the running belt, the front end slope Not only does the amount of reflected light rays clearly differ between the surface portion and the flat bottom surface portion, but even if the flat bottom surface portion has a somewhat curved shape, the amount of change in the amount of reflected light rays is extremely small, and as a result, The detection accuracy of the front lower edge is increased, and the longitudinal dimension of the bottom side of the strip T can be measured with high precision.

Therefore, it is possible to strictly control the inner circumference length when the band T is joined into an endless shape in the next process, which greatly contributes to stabilizing the balance and uniformity of the product in the case of tire manufacturing. extruder,
By improving the mechanical precision of the conveyor line and tread cutting machine and feeding back the high-precision tread length measurement values, the dimensional accuracy of the tread length can be further improved, and the tread length can be cut into the tire carcass on the forming drum during the forming process. It has excellent effects, such as making it possible to automate the work of wrapping.

[Brief explanation of the drawing]

The figure is a partially cutaway perspective view of one embodiment of the length measuring device of the present invention. 1... Floodlight of the first measuring means, 2... Also a high-speed line sensor camera, 3a... Photoelectric switch,
4... Floodlight of second measurement means, 5... Also high-speed line sensor camera, 15... Arithmetic control means, C
...Transportation means, B ₁ , B ₂ ...belt.

Claims (1)

[Claims] 1 The running center line portion of the spreading belt,
A conveyance means having a section on which a belt-shaped body as a length measurement object whose cross-sectional shape parallel to the longitudinal side edge is approximately a parallelogram is mounted so as to allow light to pass therethrough, the longitudinal side being parallel to the running direction of the belt. , and a photoelectric sensor for detecting the front end of the belt-shaped body mounted on the belt in a forward-inclined state such that the inclined surface portion of the front end faces the belt at an acute angle, and for indicating that the belt-shaped body has arrived at a predetermined position. a switch, a light projector for projecting light onto the inclined surface portion of the belt-shaped body; and a light projector provided below the running belt of the conveying means so as to be able to receive the light beam projected from the projector and reflected from the slope surface portion as a light amount component in the running direction of the belt. a high-speed line sensor camera for detecting the lower end edge of the inclined surface portion in a photoelectric conversion manner;
a second measuring means that is spaced apart from the measuring means and has a floodlight and a high-speed line sensor camera installed at predetermined positions above and below the belt, and at the same time the photoelectric switch receives a signal emitted by detecting the front end of the belt-shaped body; The first measuring means and the second measuring means are actuated to simultaneously measure the length of the strip existing within the field of view captured by both the high-speed line sensor cameras, and the sum of these two measured values and the offset value is calculated. What is claimed is: 1. A length measuring device for a band-shaped object, comprising an arithmetic control means for calculating the length of the band-shaped object.