JP2541277B2 - Can internal pressure inspection device - Google Patents

Description

TECHNICAL FIELD The present invention relates to an improvement of an apparatus for inspecting the internal pressure of a can in which juice or the like is enclosed.

[Prior Art] Generally, a can in which a beverage or the like is enclosed has a serious defect such as buckling of a can lid when the can inner pressure after enclosing the contents is too large, and is easily deformed by an outside pressure when the can is too small. . Therefore, in the beverage manufacturing plant, strict inspection of the can internal pressure is carried out, and only those whose can internal pressure is within a certain range are shipped.

By the way, as an apparatus for inspecting the internal pressure of a can, Japanese Patent Laid-Open No.
There are known devices disclosed in JP-A-163532 and JP-A-59-157537.

In the former, the can is passed between a pair of pressing bodies having a space slightly narrower than the outer diameter of the can body, and the reaction force acting on one of the pressing bodies at that time is measured to measure the internal pressure of the can. It is composed. However, there is a manufacturing error in the outer diameter of the can, and since the can body is not a perfect circle, the outer diameter of the can body greatly differs depending on the orientation of the can. For this reason,
The inspection device as described above has a drawback in that the amount of pressing by the pressing body differs depending on the outer diameter of the can body, resulting in a large measurement error.

On the other hand, in the latter, the can is clamped and moved by a pair of endless belts, the same portion of the can body is pressed by two sets of pressing bodies having different pushing amounts, and the difference in reaction force acting on the pressing bodies of each set. Is configured to measure the internal pressure of the can. Such an inspection device has an advantage that the internal pressure of the can can be measured without being affected by the error in the outer diameter of the can body.

[Problem to be Solved by the Invention] However, in the latter inspection device, it is necessary to set the pushing amount of one of the pressing bodies to be considerably large in order to obtain the difference in the reaction force acting on the pressing body. For this reason,
In many cases, dents due to the pressing body are easily generated on the can body, resulting in defective products. Moreover, in the above inspection device, the cans are clamped by the endless belts and moved without rotating. Therefore, the cans must be strongly clamped in order to pass between them against the strong pushing force of the pressing body. There is. Therefore, the holding force of the endless belt increases the internal pressure of the can, and in any case, the purpose of accurately measuring the internal pressure of the can has not been achieved.

[Object of the Invention] The present invention has been made in view of the above circumstances, and an object thereof is to provide a can internal pressure inspection device capable of accurately measuring can internal pressure without damaging the can body. To do.

[Means for Solving the Problems] A first feature of the present invention is to provide a fixed pressing portion and a fixed pressing portion which are provided so as to be able to approach and separate from the fixed pressing portion, and which are biased toward the fixed pressing portion by a constant pressure. In addition, the movable pressing body separated from the fixed pressing portion by a dimension smaller than the outer diameter of the can and the can is moved to pass between the fixed pressing portion and the moving pressing body against the biasing force of the moving pressing body. And a transport mechanism for
The moving pressing body is provided separately from each other in the axial direction of the can, and a first pressing body for pressing the shoulder portion of the can and a second pressing for moving the can body separately from the first pressing body. It is composed of a body and a measuring means for measuring the relative position of the first and second pressing bodies.

A second feature of the present invention is that the can internal pressure inspection device having the above-mentioned structure measures a distance to a center portion of an end surface of the can when the can passes between the fixed pressing body and the moving pressing body. The point is that a sensor is provided.

Furthermore, it is preferable that the transport mechanism is configured to roll and move the can on the surface of the support member provided on the moving pressing body side.

[Operation] When the pressing body is pushed into the can body with a constant pressure,
There is a certain correlation between the amount of pushing and the pressure inside the can. Therefore, the relative displacement between the position of the pressing body when the pressing body is in contact with the can body with almost no load, and the position of the pressing body when the pressing body is pushed into the can body by applying a constant biasing force. By measuring, the actual pressing amount of the pressing body can be known, and the accurate value of the internal pressure of the can can be measured.

Here, the shoulder of the can is hardly deformed by a pushing force below a predetermined value, while the can body is deformed by a relatively small pushing force. In the above-described first can internal pressure inspection device, since the first pressing body presses the shoulder portion and the second pressing body presses the can body, the actual pressing amount by the second pressing body is the first pressing body and the second pressing body. It can be accurately grasped by measuring the relative position of. This relative position is measured by the measuring means, and the measured value is converted into an accurate value of the internal pressure of the can. Therefore, it is possible to prevent the harmful damage to the can body from occurring by reducing the pushing force of the second pressing body, and it is possible to accurately measure the can internal pressure.

In the second can internal pressure inspection device, the first can internal pressure inspection device measures the distance to the center of the end face of the can when the can passes between the fixed pressing body and the movable pressing body. Since the distance sensor is provided, it is possible to accurately measure a wide range of can internal pressure. That is, when the pushing force of the second pressing body is reduced, the can body is less likely to be deformed in the high can internal pressure region, and the can internal pressure cannot be accurately grasped from the pushing amount of the second pressing body. On the other hand, when the internal pressure of the can becomes high, expansion called buckling occurs in the can lid. Therefore, the internal pressure in the high pressure range can be accurately measured by measuring the expansion amount with the distance sensor.

Further, if the transport mechanism is configured to roll and move the can on the surface of the support member provided on the moving pressing body side,
Since the can comes into rolling contact with the moving pressing body, it is possible to more effectively prevent the occurrence of scratches on the can body.

[Embodiment] An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. FIG. 1 is a plan view showing a preferred embodiment of the first feature of the present invention, and FIG. 2 is II-II of FIG.
FIG. In FIG. 2, reference numeral 1 is a belt conveyor. The belt conveyor 1 has an endless belt 2 that is wound around a pair of pulleys (not shown) and can run in the arrow X direction in FIG. Frames 3 are arranged on both sides of the belt conveyor 1.

A pair of pulleys 4 and 5 are arranged on one side of the frame 3 so as to be spaced apart from each other in the front-rear direction (the X and Y directions in the drawing). A backup plate (fixed pressing portion) 6 and a backup roller 7 are arranged in the middle of the pulleys 4 and 5. An endless belt (drive unit) 8 is wound around the pulleys 4 and 5 so as to be hung on the backup plate 6 and the backup roller 7. The endless belt 8 can be run in the same direction as the endless belt 2 and at a speed slightly higher than the speed of the endless belt 2 by a rotary drive mechanism (not shown) connected to one pulley 4. There is.

On the other hand, on the other side of the frame 3, as shown in FIG.
A stand 9 is attached. The stand 9 includes a pair of air cylinders 10a and 10b which are vertically spaced from each other.
Turns those piston rods 11a and 11b to the right side in the figure,
Moreover, it is supported so as to be movable in the left-right direction. The piston rod 11a of the upper air cylinder 10a is urged to the right side in FIG. 2 by a comparatively weak force. Further, the piston rod 11b of the lower air cylinder 10b is biased to the right with a slightly strong force. These air cylinders 10a and 10b have
Brackets 13a and 13b having long holes 12 are attached. Each bracket 13a, 13b has a screw 1 that penetrates the slot 12 ...
It is fixed to the stand 9 by 4 ... The air cylinders 10a and 10b are positioned in the left-right direction by the adjusting screw 15 that is brought into contact with the left side portions of the brackets 13a and 13b.

In addition, the piston rod 11a of the air cylinders 10a and 10b
The slides 16a, 16b, which are slidably supported on the stand 9 in the left-right direction, are attached to 11b. The upper slide 16a has a first pressing body 17a, and the lower slide 16b has a second pressing body. 17b is fixedly attached to the slides 16a and 16b.

The first and second pressing bodies 17a and 17b are disk-shaped and have the same shape and size, and their outer peripheral portions are formed to have a middle height. The outer circumference of the first pressing body 17a is located on the shoulder B of the can A, and when the minimum outer diameter set in consideration of variations due to manufacturing error of the can body C is set to Dmm, the endless belt is formed. 8
Is arranged so that the distance to the surface of is (D-1) mm, for example. On the other hand, the second pressing body 17b is arranged so that the distance to the surface of the endless belt 8 is (D-3) mm, for example. Then, the first and second pressing bodies 17a, 17
b is biased to the right by a constant force set on the air cylinders 10a and 10b. Furthermore, in each pressing body 17a, 17b,
As shown in FIG. 1, a plate protruding rearward
18 are attached respectively. On the other hand, measuring means 19 is attached to the frame 3. The measuring means 19 is
Measure the distance from the tip to the plate 18,
An eddy current distance sensor, an optical distance sensor, a magnetic distance sensor, etc. are preferably used to measure the relative position between the second pressing bodies 17a and 17b.

The frame 3 is provided with a pair of fixtures 20 and 21 that are separated from each other in the front-rear direction. These fixtures 20,21
Both ends of two belts (supporting members) 22, 22 respectively located below the first and second pressing bodies 17a, 17b are attached to the. The distance between the belts 22 and 22 and the endless belt 8 is set to be slightly smaller than the set minimum outer diameter D of the can body C. A backup plate 23 is supported on the left side of each of the belts 22 by a pin 24 attached to the frame 3. A gap is provided between the backup plate 23 and the belt 22. By pressing the can A against the elastic force of the belt 22 against the backup plate 23, the can A is quickly stabilized and supported. Is able to. Then, based on this configuration, the can A has the endless belt 2,
By moving 8 in the direction of the arrow X in the figure, it is fed between the endless belt 8 and the belt 22, and rolls on the surface of the belt 22 to move in the direction of the arrow X.

Next, the operation of inspecting the internal pressure of the can A by the above can internal pressure inspection device will be described.

First, the endless belts 2 and 8 are made to run in the direction of the arrow X, and the can A is erected on the endless belt 2 and supplied. Then, can A moves in the direction of arrow X,
It penetrates between the endless belt 8 and the belt 22. Then, the can A is sandwiched between the endless belt 8 and the belt 22, and moves in the arrow X direction while rollingly contacting the surface of the belt 22. Then, the can A has the first and second pressing bodies 17a and 17b.
When passing through, the first and second pressing bodies 17a and 17b are moved to the left side against the biasing force of the air cylinders 10a and 10b.

Here, since the first pressing body 17a is biased by a relatively small force that does not deform the shoulder portion B, if the outer diameter of the can body C is, for example, Dmm which is the set minimum outer diameter, The distance between the first pressing body 17a and the endless belt 8 is (D-1) mm
Therefore, move 1mm to the left and move from endless belt 8 to D.
The positions are separated by mm. On the other hand, the second pressing body 17b is pushed into the can body C by the urging force of the air cylinder 10b. If the pushing amount at this time is dmm, the second pressing body 17b
Is a position obtained by subtracting the pushing amount d from the position of the first pressing body 17a, that is, a position separated from the endless belt 8 to the left by (D-d) mm. Then, the first and second pressing bodies 17a,
The position of 17b is measured by the eddy current type distance sensor 19,
Their relative position is grasped as (D- (D-d)) mm = dmm.

If the outer diameter of the can body C is (D + 1) mm, for example,
((D + 1)-(D-1)) = 2 mm Moves to the left side and becomes a position separated from the endless belt 8 by (D + 1) mm.
On the other hand, assuming that the pushing amount of the second pressing body 17b into the can body C is emm, the second pressing body 17b is equal to the endless belt 8 by (D + 1 -E) mm The position is separated to the left. And
The relative position of the first and second pressing bodies 17a and 17b is ((D + 1)-
It is understood that (D + 1-e)) mm = emm. And
The above values d and e are replaced by a numerical value correlated with the internal pressure of the can by an electrical calculation process, and when the numerical value deviates from the set range, it is excluded as a defective product by an alarm or other means.

In such a can internal pressure inspection device, the first pressing body 17
Since the second pressing body 17b presses the can body C where the second pressing body 17b is easily deformed, the shoulder portion B in which a is hardly deformed, the actual pressing amount by the second pressing body 17b is between the first and second pressing bodies 17a and 17b. It can be accurately grasped by measuring the relative position of. Therefore, the pushing force of the second pressing body 17b can be reduced to prevent harmful damage to the can body C from occurring, and the can internal pressure can be accurately measured.
The reliability of the inspection can be greatly improved. Also,
The can A is rotated and moved to move the first and second pressing bodies 17a,
Since it makes rolling contact with the surface of 17b, it is possible to further reduce the occurrence of scratches on the can body C.

By the way, in the above can internal pressure inspection device, the first and second
Fixing the pressing bodies 17a and 17b to the slides 16a and 16b is important in preventing scratches. That is, can A
Moves while making rolling contact with the outer peripheries of the first and second pressing bodies 17a and 17b, but if the first and second pressing bodies 17a and 17b are rotatably provided on the slides 16a and 16b, This is because the rotation causes the first and second pressing bodies 17a and 17b to rotate and the contact area with the can A increases.

In the above embodiment, the can A is configured to move while rolling, but it may be configured to be clamped by a pair of endless belts and moved without rotating.
However, in this case, it is necessary to rotatably provide the first and second pressing bodies 17a and 17b to bring them into rolling contact with the can A.

Next, a preferred embodiment of the second feature of the present invention will be described with reference to FIG.

In the can internal pressure inspection device shown in this figure, the can internal pressure inspection device is provided with a distance sensor 28 for measuring the distance to the center of the end face of the can A when the can A passes through the first and second pressing bodies 17a, 17b. The distance sensor 28 is attached to a bracket 29 attached to the frame 3. As the distance sensor 28, an eddy current type distance sensor, an optical type distance sensor, a magnetic type distance sensor or the like similar to the measuring means 19 is preferably used.

In the can internal pressure inspection device, when the can A travels in the direction of the arrow X in FIG. 3 and passes through the first and second pressing bodies 17a, 17b, the first and second pressing bodies are processed in the same manner as described above. The measuring means 19 measures the positions of 17a and 17b. The distance sensor 28 continuously measures the distance to the end surface of the can A. Then, the measurement result by the distance sensor 28 is analyzed by electrical calculation processing, and the distance to the center of the end surface of the can A is extracted and replaced with a digital value correlated with the can internal pressure.

Here, FIGS. 4 and 5 show the relationship between the can internal pressure measured by another measuring method and the digital value of the measurement result by the measuring means 19 and the digital value of the measurement result by the distance sensor 28, respectively. As can be seen from these figures, the digital value of the measuring means 19 has little variation on the low pressure side of the can internal pressure, and the digital value of the distance sensor 28 shows a large change on the high pressure side. Then, of these two kinds of digital values, when the measuring means 19 is below the set lower limit value and when the distance sensor 28 is above the set upper limit value, an alarm or other means is given as a defective product. exclude.

4 and 5 show the measurement results of a can called a nooding can whose can lid is substantially flat when the contents are filled. In a no-doming can, the can lid is largely deformed with respect to the internal pressure of the can in order to improve the accuracy of measuring the internal pressure of the can. The above-mentioned can internal pressure inspection device can, of course, measure the can internal pressure with respect to the nodaling can with high accuracy, but it also accurately measures the doming can with the can lid expanded outward. be able to.

FIG. 6 shows the relationship between the internal pressure of the doming can and the digital value of the measurement result by the distance sensor 28. As can be seen from this figure, the degree of change in the digital value is greater than that of the nodal can. However, the digital value shows a sufficient change to measure the internal pressure of the can.

As described above, in the above can internal pressure inspection device, the can internal pressure can be accurately measured even on the high pressure side, so that reliable inspection can be performed in a wide pressure range, and it corresponds to all types of cans. be able to.

Next, FIG. 7 shows another embodiment of the second feature of the present invention. In this figure, reference numeral 30 is a bracket, which is attached to the frame 3. The bracket 30 has an L-shape in a side view, and an end portion of a plate (contact portion) 31 whose longitudinal direction is directed to the traveling direction of the can A is attached to an end portion extending downward of the bracket 30. There is.
The plate 31 is made of a slightly hard and elastically deformable synthetic resin having a small coefficient of friction, and has a longitudinal intermediate portion formed flat and bent upward at both ends,
The exterior is shaped like a sled.

A coil spring 32 is attached between the left end of the plate 31 and the bracket 30. The coil spring 32 urges the end of the plate 31 downward, and the flat portion is inclined to the left. Further, the distance between the plate 31 and the endless belt 2 is set to be smaller than the height of the can A, so that the plate 31 comes into sliding contact with the edge of the sent can A. Then, the can A pushes up the left side portion of the plate 31 against the force of the coil spring 32 as it moves, and
By the time it reaches the pressing bodies 17a, 17b, the entire circumference of the edge portion is in contact with the plate 31.

Further, a distance sensor 33 is attached to the back side of the flat portion of the plate 31.

In the can internal pressure inspection device, when the can A travels in the direction of the arrow X in FIG. 7, first, the edge of the can A facing the traveling direction abuts the lower surface of the plate 31. Then, the edge portion of the can A moves while slidingly contacting the plate 31, whereby the right end portion of the plate 31 is elastically deformed and the left portion is pushed up against the force of the coil spring 32. And can A
When passing through the first and second pressing bodies 17a and 17b, the entire circumference of the edge of the can A is in contact with the plate 31. At this time, the positions of the first and second pressing bodies 17a and 17b are measured by the measuring means 1 in the same manner as described above.
9 measures. Further, the distance sensor 33 continuously measures the distance to the end surface of the can A. Then, the measurement result by the distance sensor 33 is analyzed by electrical calculation processing, and the distance to the center of the end face of the can A is extracted and replaced with a digital value correlated with the can internal pressure.

In such a can internal pressure inspection device, the distance sensor 33 is
Since it moves in the vertical direction depending on the height of the can, the effect that the variation in the height of the can A on the measurement result can be reduced can be obtained.

Next, FIG. 8 shows still another embodiment of the second feature of the present invention. The can internal pressure inspection device shown in this figure
A drive wheel 43a and a plurality of pulleys 43 are mounted on a frame 42 that is movably supported in the vertical direction by guide shafts 40 and is urged downward by a coil spring 41.
The endless belt 44 wound around the endless belt 44 is arranged, and the frame 42 is provided with a backup plate 45 which is in sliding contact with the back surface of the endless belt 44, and the distance sensor 46 is attached to the backup plate 45. The can A is guided below the backup plate 45 by running 44, and the backup plate 45
The distance sensor 46 measures the distance to the end face of the can A through a hole 45a formed in the center of the can.

In such a can internal pressure inspection device, it goes without saying that the same effects as described above are obtained, but since there is no member that wears like the plate 31, maintenance and inspection is easy.

[Effects of the Invention] As described above, in the first can internal pressure inspection device of the present invention, the fixed pressing portion and the fixed pressing portion are provided so as to be able to approach and separate from each other, and a constant pressure is applied to the fixed pressing portion side. A moving pressing body that is biased and is spaced from the fixed pressing portion by a size smaller than the outer diameter of the can, and the moving pressing body is moved between the fixed pressing portion and the moving pressing body by moving the can to the biasing force of the moving pressing body. A first pressing body that is provided to be separated from each other in the axial direction of the can and that presses the shoulder portion of the can, and a moving mechanism that moves separately from the first pressing body. And a second pressing body that enables the can body to be pressed, and further,
Since the measuring means for measuring the relative position between the first and second pressing bodies is provided, the can body pushing amount by the second pressing body can be accurately grasped. Therefore, the can internal pressure can be accurately measured, and the reliability of the inspection can be significantly improved. Further, since the pushing force of the second pressing body can be set to be small, it is possible to prevent damage to the can body.

Also, in the second can internal pressure inspection device of the present invention, the can internal pressure inspection device measures a distance to the center of the end face of the can when the can passes between the fixed pressing body and the moving pressing body. Since the sensor is provided, the internal pressure of the can on the high pressure side can be accurately measured, and highly reliable inspection can be performed in a wide range of the internal pressure of the can.

Further, if the transport mechanism is configured to roll and move the can on the surface of the support member provided on the moving pressing body side,
Since the can comes into rolling contact with the moving pressing body, it is possible to obtain excellent effects such as the occurrence of scratches on the can body can be more effectively prevented.

[Brief description of drawings]

1 and 2 show an embodiment of a first can internal pressure inspection device of the present invention, FIG. 1 is a plan view showing the outline thereof, and FIG. 2 is a sectional view taken along line II-II of FIG. FIG. 3 shows an embodiment of the second in-can pressure inspection device of the present invention, and III-I in FIG.
A sectional view taken along line II, FIGS. 4 to 6 are diagrams showing the relationship between the internal pressure of the can and the digital value by the measuring means, and FIG. 7 is another embodiment of the second internal pressure inspection device of the present invention. 2 is a sectional view taken along the line VII-VII in FIG. 2, and FIG. 8 is a sectional view taken along line VII-VII of FIG.
FIG. 8 is a sectional view taken along line VIII-VIII. 6 ... Backup plate (fixed pressing part), 8 ... Endless belt (driving part), 17a ... First pressing body, 17b ... Second pressing body, 19 ... Measuring means, 22 ... Belt (supporting member) ), 28 …… distance sensor, 31 …… contact part, 33 …… distance sensor, 44 …… endless belt (contact part), 46 …… distance sensor, A …… can, B …… shoulder part, C …… Can body.

Claims (3)

(57) [Claims] 1. A fixed pressing portion, which is provided so as to be able to approach and separate from the fixed pressing portion, is biased toward the fixed pressing portion by a constant pressure, and is smaller than the outer diameter of the can with respect to the fixed pressing portion. The moving pressing body is provided with a moving pressing body spaced apart from each other and a transport mechanism for moving the can to pass between the fixed pressing portion and the moving pressing body against the biasing force of the moving pressing body. And a second pressing body that is provided separately from each other in the axial direction and presses the shoulder portion of the can, and a second pressing body that is movable separately from the first pressing body and presses the can body. An apparatus for inspecting internal pressure of a can, comprising: measuring means for measuring a relative position between the first and second pressing bodies. 2. The can internal pressure inspection device according to claim 1, further comprising a distance sensor for measuring a distance to a central portion of an end surface of the can when the can passes between the fixed pressing body and the moving pressing body. A can internal pressure inspection device. 3. The transport mechanism includes a support member provided on the side of the moving pressing body and a drive unit for rolling and moving the can on the surface of the support member. The can internal pressure inspection device according to item 1 or 2.