JPH05141962A - Can bottom section withstand pressure inspecting device for pressure two-piece can - Google Patents

Abstract

PURPOSE:To simply and correctly measure the can bottom section withstand pressure of a neck-formed can by supporting a can body on the packing of a cylindrical sleeve, thrusting the tip of the sleeve to a top plate, and keeping the can body in the sealed state. CONSTITUTION:A can body A is erected on a pedestal 7, air is fed from an air feeding means 16, and a cylindrical sleeve 13 is lifted by a piston 6. A hollow shaft 5 is fixed to a bottom plate 2, thus a packing 9 is soon brought into contact with the outer face of a can bottom shrunk section 35. The sleeve 13 is continuously lifted together with the can body A, and it is stopped when the tip 13a is brought into contact with the top plate 10 while the reversible distance of the can bottom is kept. Air is fed to an air feeding means 12, and the pressure in a sealed chamber C, i.e., the internal pressure of the can, is increased. The pressure is detected by a pressure sensor 19 and recorded during this time. A recess 33 is finally reversed toward the outer face of the can almost instantly by the increase of the pressure. The air vibration sound around the recess 33 generated at this time is sensed by an acoustic sensor 18, the pressure immediately before the reversal is compared with the reference value as the withstand pressure value of the recess 33 by a computer to judge the success or failure.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for inspecting pressure at the bottom of a can of a pressure-resistant two-piece can manufactured by a known means such as an impact extrusion method, a deep drawing method or an ironing method for drawing. The present invention relates to an improvement of a device for automatically measuring and recording (buckling strength against the internal pressure of a can due to the content after filling the content such as beer, carbonated drink, and aerosol) and inspecting the quality of pressure resistance.

[0002]

2. Description of the Related Art At the bottom of a can of a pressure-resistant two-piece can that is currently on the market, a concave recess is formed toward the inside of the can in order to counter the internal pressure of the can after the contents are filled.

The depth of the depression (recess) is referred to as the bottom depth. Since the bottom depth greatly affects the ability to withstand the internal pressure of the can (pressure resistance), the pressure resistance of the can is evaluated. Usually, the bottom depth dimension is measured, and the pressure resistance performance is estimated from the measured value. However, although the pressure resistance performance is greatly influenced by the bottom depth, other factors that may affect the pressure resistance include the plate thickness of the raw material and the shape of the recess, and even though it was once determined to be appropriate due to the influence of these factors. In many cases, the pressure resistance is lowered, and after filling the contents, the container cannot withstand the internal pressure of the can, and the can bottom concave portion is momentarily inverted to the can outer surface side (generally referred to as buckling).

In order to prevent such an accident, in addition to sampling from the manufacturing line and controlling the bottom depth dimension, internal pressure is actually applied to the can under a sealed condition to measure and control the pressure resistance performance. is doing.

The structure and function of the pressure resistance inspection device for the bottom of the can that has been used so far will be described with reference to the drawings showing the essential parts thereof.

FIG. 8 is a perspective view of a main part in a state where a closed chamber is formed in the can body, FIG. 9 is a schematic sectional view taken along line IX-IX of FIG. 8, and FIGS. FIG. 10 is a schematic plan view showing the attaching mechanism, FIG. 10 shows before fastening, and FIG. 11 shows after fastening.

This is to keep the can body of a two-piece can A having a can bottom 32 including a can bottom recess 33 recessed toward the inside of the can and a reduced diameter part 35 around the can bottom closed and pressurized. Then, the internal pressure value of the can is continuously measured by the pressure sensor, and the physical change amount due to the reversal when the can bottom concave part is reversed to the outer surface side of the can is detected by the electric sensor, and the internal pressure value immediately before the reversal is measured. An inspection device that records the pressure resistance value of the bottom of the can and compares the pressure resistance value with a predetermined reference value to determine whether the pressure resistance value is within an allowable range, and a support base 101 having a through hole in the center. A mandrel 105 for holding the inside of the can, which is provided above the mandrel 105, and a vertically movable shaft 106 that extends vertically through the mandrel 105.

The mandrel 105 includes a cylindrical fixed block 102 fixedly mounted on a support 101, a rubber packing 103 provided on the fixed block 102, and an upper mortar-shaped moving block provided on the fixed block 102. In order to receive the shaft 106, a through hole is formed in the central portion like the support base. This mandrel 1
The outer diameter of 05 is slightly smaller than the inner diameter of the can to be inspected (about 0.1 mm) so that the can body can be easily held.
Is processed into.

The shaft 106 penetrates the support base 101, the fixed block 102, and the rubber packing 103 in the vertical direction, has a moving block 104 screwed to the tip, and can move up and down together with the moving block 104. An air source is connected to the other end of the extension, and a through hole 120 through which air passes is provided in the shaft center.
A solenoid valve 107 and a throttle valve 10 are provided in the middle of the piping.
8. A pressure sensor 109 is provided.

On the other hand, 110 is a shaft 1 below the support base 101.
It is a ring that is externally attached to 06 and is stopped at an appropriate position, and a clamp lever 111 that moves the shaft 106 up and down with respect to the support 101 is screwed to the ring by a pin 112. The outer peripheral surface of the screwed portion of the clamp lever 111 has a cam shape. When the clamp lever 111 is lifted, the cam 111a pushes the lower surface of the support base 101, and the reaction thereof lowers the shaft 106 by a predetermined distance. When the shaft 106 descends, the moving block 104 screwed to the upper end of the shaft 106 descends, and as a result,
The rubber packing 103 sandwiched between the moving block 104 and the fixed block 102 is compressed and radially expanded.

The can A is a mandrel 1 with the can bottom 32 facing up.
Since it is inserted into 05, this rubber packing 103
Due to its radial expansion, it plays a role of closely contacting the inner surface of the can and sealing the inner surface of the can, and the inner wall surface of the can and the mortar-shaped space form a closed chamber M (FIG. 9).

The clamp lever 11 that has been lifted
A lever pin 111b is attached to the hook 1, and is engaged with and held by a hook 113 provided on the support base 101.

In this state, if air for pressure inspection is supplied to the can covered with the mandrel 105, an upward force is applied to the can and the can comes out of the mandrel 105. An outer tightening mechanism for preventing this is schematically shown in FIGS. 10 and 11.

In the figure, reference numerals 114a and 114b denote outer cylinders obtained by dividing a cylindrical member into two parts, and the support base 10 is provided outside each outer cylinder.
The hinge ring fixed to No. 1 and fitted in the hinge pin 115 (FIG. 9) which is erected in parallel with the mandrel 105 is fixedly provided and has a hinge action. The inner diameter of the cylindrical member is slightly larger than the outer diameter of the can (about 0.1 mm larger). The outer cylinder 114a is provided with a double-link type clamp lever 116, and the other outer cylinder 114b.
A receiving member 118 of a pin 117 provided on the clamp lever 116 is attached to the.

Using the jig having the above structure, the pressure resistance of the can bottom is measured as follows. First, as shown in FIG. 8, the can A to be inspected is placed on the mandrel 105, and the clamp lever 111 is lifted in the direction of arrow a.
The rubber packing 103 is expanded to shield the inner circumference of the can body from the atmosphere (FIG. 9). Next, the split outer cylinders 114a, 1
14b is closed, the pin 117 is hooked on the metal 118,
Turn the clamp lever 116 in the direction of arrow B to tighten the outer peripheral portion of the can, and press the mandrel 105 and the outer cylinders 114a, 114a.
Clamp the can with b (Figs. 8 and 11). When tightening, pay attention to tightening so as not to cause a defective seal. After that, the solenoid valve 107 is operated, air is supplied into the closed chamber M through the through hole 120 of the shaft 106, the pressure in the closed chamber is gradually increased, and the internal pressure value immediately before the can bottom recess buckles is detected by the pressure sensor 109. Then, the value is compared with a reference value to measure the pressure resistance performance and quality control is performed.

[0016]

In the apparatus having such a structure, first, there is a drawback that the neck-molded can cannot be inspected as it is. FIG. 5 shows a neck-molded two-piece can. The can bottom 32 extends from the lower end of the can body side wall 31 to the can bottom recess 33 through the corner portion 34, the reduced diameter portion 35, and the rim portion 36 (note that b is While showing a bottom depth), a neck portion 37 narrowed toward the inside of the can and a leading end flange 38 following the neck portion 37 are formed at the upper end of the side wall.

By the way, in the above conventional apparatus, since the can body is inserted into the mandrel 105 in an inverted state, in order to inspect a neck-molded can, the squeezed neck portion is cut off with scissors or the like, and then removed. Otherwise, it will not be possible to insert it into the mandrel, and the work will be troublesome. Therefore, the present condition is to measure with a so-called trim can before forming the neck.

However, there is a difference between the can bottom withstand pressure value of the trim can during the can making process and the can bottom withstand value of the neck can of the final product that has passed through the oven several times after that due to the heat history. Therefore, it is necessary to add a correction value to the pressure resistance measurement value of the trim can to calculate the pressure resistance value of the neck can, which not only can not promptly respond to quality control at the manufacturing site, but also the correction of the correction value The withstand voltage value changes, and the reliability of the withstand voltage value is low.

However, if the outer diameter of the mandrel is made thin so as to fit the opening diameter of the neck can so that the neck can can be inverted and inserted as it is, the insertion of the can itself becomes possible. However, instead, the man can be clamped by the mandrel 105 and the outer cylinders 114a and 114b, and the rubber packing 1
It is necessary to increase the radial expansion amount of 03, and as a result, the mandrel loses the function of fixing and holding the can in practical use. By the way, the force to pull the can out of the mandrel due to the internal pressure of the can is that the withstanding pressure value of φ66 diameter is 6.5.
In the case of a can of kg / cm ² , a large force of about 220 kg is required, and the can cannot be held only by the rubber packing and the outer cylinder.

Further, in the conventional device, the clamp lever 11
By lowering the shaft 106 by pulling up 1 in the direction of arrow a, the rubber packing 103 is compressed and expanded in the radial direction, and adheres to the inner surface of the can body to seal the inner surface of the can from the atmosphere. Depending on the fixed position, the amount of lowering of the axis will change slightly. For example, when the amount of lowering of the shaft is small, the expansion of the rubber packing becomes small and the sealing ability is lowered, so that an accurate pressure resistance value cannot be measured. On the contrary,
When the descending amount is large, there is a structural problem that the expansion of the rubber packing becomes too large and a crack occurs in the can body, and there is a drawback that it takes time and skill to adjust and operate the ring position.

It is an object of the present invention to provide a simple can bottom withstand pressure inspection device which does not cause these problems.

[0022]

[MEANS FOR SOLVING THE PROBLEMS] A can body of a two-piece can having a can bottom having a can bottom recess which is recessed toward the inside of the can and a reduced diameter portion around the can is kept sealed and pressurized. By continuously measuring the internal pressure value of the can with a pressure sensor, the electrical sensor detects the amount of physical change that accompanies the inversion of the bottom of the can toward the outer surface of the can. In an inspection device for recording as a bottom withstand voltage value and comparing the withstand voltage value with a predetermined reference value to determine whether it is within an allowable range, a can bottom recess of a can body seated in an upright state. A hollow shaft provided with a pedestal having a protrusion that fits inside, and a concentric outer side of the hollow shaft, and an inner diameter that is not smaller than the outer diameter of the flange of the can body or the can body diameter, whichever is larger. A cylindrical sleeve, the height of the can being measured from the tip of the cylindrical sleeve. A cylindrical sleeve having an annular packing fixedly contacting the outer surface of the reduced diameter portion of the can body on the inner peripheral surface of the cylindrical sleeve at a distance of at least or more, and the hollow shaft. An elevating device that supports the can body by the packing of the cylindrical sleeve by relative movement with the cylindrical sleeve and relatively moves in the axial direction of the can, and a reduced diameter of the can body on the pedestal from the packing of the cylindrical sleeve. The top plate provided above the pedestal with a distance not less than the sum of the distance to the base and the distance at which the can bottom recess can be reversed to the outer surface of the can without being obstructed by the base 7. A can bottom portion of a pressure-resistant two-piece can, which is attached to a plate and comprises air supply means for pressurizing the inside of the can to be inspected, which is kept sealed by the top plate and the cylindrical sleeve. Withstand pressure inspection device.

[0023]

In the present invention, with the cylindrical sleeve, the can body can be easily kept in a hermetically sealed state by supporting the can body on the packing while the tip of the cylindrical sleeve abuts the top plate. Also, the can body is held in an upright state without any external tightening means, and even in the case of a neck-formed can, the measurement can be performed as it is without cutting off the neck portion.

[0024]

[Embodiment 1] This embodiment describes a case where a hollow shaft is in a fixed position and a cylindrical sleeve holds a can body and moves up and down.

FIG. 1 is a front sectional view of the apparatus of this example in a state before measurement, and FIG. 2 in a state during measurement.

In these drawings, A indicates a pressure-proof two-piece can to be inspected, which is different from that in the conventional apparatus and is placed upright, that is, the can bottom is placed below and the can opening is placed above. The form is as shown in FIG. In this example, the can height is 167.
mm, internal volume 500 ml, can diameter 66 mm, and angle of reduced diameter portion 45 ° (described later) were used.

Reference numeral 1 denotes a base whose central portion is opened in a large circle, and a disc-shaped bottom plate 2 is fixedly provided so as to cover the opened portion. The bottom plate 2 has a through hole 2a at the center.
A hollow shaft 5 is fixed to the bottom plate 2 so as to communicate with the hole 2a. At the tip of the hollow shaft 5, the can bottom recess 3 of the can A to be inspected is formed.
The pedestal 7 having an annular protrusion 71 that fits in 3 is attached,
The inspected can sits upright on this pedestal.

Reference numeral 6 denotes a piston arranged on the outer periphery of the hollow shaft 5, which has a structure of fitting with the shaft 5 and a cylindrical outer cylinder 3 (described later). The outer peripheral surface of the shaft 5 and the outer cylinder 3 are fitted together. Slide up and down along the inner surface of the. Incidentally, 14 and 14 'are packings for preventing air leakage.

Reference numeral 4 denotes two round bars fixed to the bottom plate 2 further outside the outer cylinder 3, and has a disk-shaped top plate 10 at the upper end thereof.
Is fixed.

A disk-shaped intermediate plate 8 is fixed to the center of the round bar 4, and the outer cylinder 3 is sandwiched and fixed between the intermediate plate 8 and the bottom plate 2.

Reference numeral 13 denotes a space between the hollow shaft 5 and the outer cylinder 3,
It is arranged concentrically with an annular packing 9 to be described later so as to pass through the shaft 5 and is fixed to the upper portion of the piston 6, and moves up and down as the piston slides up and down. A cylindrical sleeve, the outer peripheral surface of which is
The inner peripheral surface of the intermediate plate 8 is rubbed. Therefore, the hollow shaft 5 and the cylindrical sleeve 13 are arranged in the central space portion of the disk-shaped intermediate plate.

The inner diameter of the cylindrical sleeve 13 is the can body A.
The outer diameter of the flange portion 38 or the can body diameter, whichever is larger, is set to a size that is not smaller than the larger one, but as much as possible, a space is not formed between the inner surface of the cylindrical sleeve 13 and the outer surface of the can body. Good to do. The reason for this is that the packing described below and the reduced-diameter portion are in close contact with each other.

An annular packing 9 is fixed to the inner peripheral surface of the cylindrical sleeve 13 for contacting with the outer surface of the reduced diameter portion 35 of the can body A for sealing.
Starting from the tip 13a of the cylindrical sleeve 13 to the can height H of the can A (FIG. 5), that is, from the can open end to the can bottom rim portion 3
It is placed down by a distance D (Fig. 1) that is equal to or greater than the size of the 6 tips. If this is not done, the tip of the cylindrical sleeve 13 cannot contact the lower surface of the top plate 10 at the time of measurement, and the closed structure will not be formed (which will be described later).

As shown in FIGS. 5 and 6 (enlarged view of Y portion in FIG. 5), the reduced diameter portion 35 of the can bottom 32 has a corner portion 34 connected to the can body side wall 31 and a concave portion 33. The portion P-Q between the continuous rim portion 36 is indicated (here, it is shown as a straight line, but it may be a curved line as shown in FIG. 7). Thus, the packing 9 has a slanted surface 91 that contacts the outer surface of the reduced diameter portion.
(FIG. 1), the cylindrical sleeve 13 is fitted into an annular groove 13b provided on the lower inner surface of the cylindrical sleeve 13, and is held in contact with the top of the piston 6. In addition, in FIGS.
The r of the corner portion 34 is often 2 to 3 mm, but the r of the rim portion is gusseted. Also, the angle θ of the reduced diameter portion 35 in FIG.
Is generally between 30 and 55 °.

The top plate 10, which is supported by the round bar 4 as described above, must be located a certain distance above the projection 71 of the pedestal 7 at the tip of the hollow shaft 5 as a starting point. In the state before measurement (FIG. 1), the certain distance is from the packing 9 of the cylindrical sleeve 13 to the can bottom reduced diameter portion 35 (strictly speaking, the reduced diameter portion upper end Q.
(See FIG. 6) and a distance more than the sum of the distance d and the distance at which the recess 33 of the can bottom supported by the packing and separated from the base can be buckled without being obstructed by the base.

Generally, the mechanism of buckling on the bottom of the can is that when pressure is applied to the can, initial inversion occurs inside the recess, then the rim extends outward, and the material of the recess becomes rim. The depth of the recess gradually becomes smaller, and finally the entire recess including the rim portion is inverted and back-limbed. Reference numeral 33 ′ in FIG. 2 indicates a back-ring recess, and as is clear from the figure, the pedestal 7 must be separated from the bottom of the can by a distance that does not interfere with the buckling of the recess. If you do not do it, or if you buckle it will be incomplete and you will not be able to perform correct inspection.

A cylindrical sleeve 13 is provided on the lower surface of the top plate 10.
When the tip 13a of the can comes in contact with the lower surface of the top plate 10, the can A, which is closely packed in the upper end portion of the cylindrical sleeve, is placed on the packing 9 together with the packing 9 and the cylindrical sleeve 13.
A lid member (plug) 11 for fixing and protecting the closed chamber C or the closed space C (FIG. 2) from the atmosphere is secured. 15 is a packing for preventing air leakage provided on the outer periphery of the lid member.

Reference numeral 12 denotes an air supply means attached to the top plate 10 for sending air into the can which is kept in a hermetically sealed state through a through hole in the central portion of the top plate and the lid member.

Reference numeral 19 is a known pressure sensor for continuously detecting a change in pressure value in the can, 16 is an air supply means provided on the bottom plate 2 at a position corresponding to the piston 6, and 17 is an intermediate plate 8.
And an air supply means 18 that is opened in a gap between the cylindrical sleeve 13 and the outer cylinder 3, and 18 is a sensor that detects a physical change amount due to reversal of the can bottom recess during buckling. It is an acoustic sensor for obtaining a physical change in sound and detecting the change, and is installed immediately below the pedestal 7 via a collar 18a having an appropriate through hole. Although the mounting position of the acoustic sensor is not limited, it is difficult to mount the acoustic sensor on the inside of the can due to the structure of the jig, and it is difficult to mount it on the movable part. At the position of this example, it is attached inside the jig,
It is rational because it is less affected by noise other than the buckling, is not exposed to the internal pressure of the can, and is located near the bottom of the can. 20 and 20 'are can detecting sensors provided on the round bar 4 between the intermediate plate 8 and the top plate 21, 21 is an electromagnetic valve for supplying air to the air supply means 12, and 22 is an air amount adjusting throttle valve. Is.

Next, the function of this device will be described. First, as shown in FIG. 1, the can body A is placed on the pedestal 7 in an upright state, and the annular projection 71 is supported by being aligned with the can bottom recess 33. When detecting it in cans detecting sensor 20, 20 ', to send a measurement start signal control circuit, from the air supply means 16 air (in this example the air pressure 4~5kg / cm ²⁾ blowing, pushing up the piston 6. Since the cylindrical sleeve 13 is fixed on the piston, it rises together with the piston 6.

On the other hand, since the hollow shaft 5 is fixed to the bottom plate 2 and does not move, the packing 9 (slope 91) will soon occur.
However, it comes into contact with the outer surface of the reduced diameter portion 35 of the can bottom.

The cylindrical sleeve 13 is further raised while the can body A is placed on the packing 9, so that the can body A is placed between the can bottom and the pedestal.
With the recess 33 kept at a distance sufficient for buckling without being obstructed by the pedestal 7 (about 16 mm above the pedestal protrusion in this example), the tip 13a of the dent 33 contacts the lower surface of the top plate 10 and stops the upward movement (Fig. 2).

From the cylindrical sleeve tip 13a to the packing 9
To the distance D (185 mm in Fig. 1 and this example) is
From the height of the can body (when the lid member 11 is used, a distance equal to or greater than the sum of the can height H of the can A and the distance E from the lower surface of the top plate 10 to the lower surface of the lid member 11 (FIG. 1)) Since it is not short, when the packing 9 supports the can body, the cylindrical sleeve tip 13a cannot be located below the can opening surface, and the lower surface of the top plate 10 (using the lid member 11 is used). In this case, since the lower surface of the lid member 11 is located above the pedestal by the above-mentioned certain distance (see paragraph 0035), the cylindrical sleeve 1
When the tip 13a of 3 hits the lower surface of the top plate and stops rising, the can body A is supported by the packing 9 of the cylindrical sleeve 13 at a position sufficiently separated from the pedestal 7, as shown in FIG. Moreover, it is in the closed chamber C formed by the top plate 10 and the cylindrical sleeve 13.

Then, the solenoid valve 21 is opened, and air (9.5 kg / cm ^{2 in} this example) is gradually supplied to the pneumatic supply means 12 while being throttled by the throttle valve 22. Along with this, the pressure in the closed chamber C, that is, the pressure in the can increases. At this time, the can bottom concave portion communicates with the atmosphere through the through hole of the collar portion 18a supporting the acoustic sensor 18, the hollow portion of the hollow shaft 5 and the hole 2a of the bottom plate 2, and the pressure of the closed chamber C is applied to the can. It plays the role of giving internal pressure.

The pressure during this period is continuously detected by the pressure sensor 19 and is sent to a circuit (not shown) for sequentially recording the continuously taken pressure values.

The can bottom concave portion of the can cannot withstand the gradually increasing pressure, and finally it is almost instantaneously inverted toward the outer surface of the can.
That is, buckling. At this time, the air around the recess vibrates to generate a sound, and the sound is sensed by the acoustic sensor 18, converted into an electric signal, and the pressure immediately before buckling (6.5 kg / cm ^{2 in} this example) is applied to the can. The pressure resistance value of the bottom recess is sent to a computer (not shown).

The computer compares the sent withstand voltage value with a preset reference value, and if the measured value is within the reference value, it passes, and if it is outside the reference value, it fails. The value (6.5 kg / cm ² ) was a passing value. A known device can be used as such a measuring device.

Next, the electromagnetic valve 21 is opened to the atmosphere in response to the electric signal captured by the acoustic sensor 18, and the air supply means 12 is supplied.
After discharging the air from the chamber and releasing the pressure in the closed chamber C,
Air is discharged from the air supply means 16 and at the same time air is supplied from the air supply means 17 at a pressure of 4 to 5 kg / cm ² ,
The piston 6 was lowered. As the piston descends, the cylindrical sleeve 13 also descends, and the inspected can A, which was lifted by the rubber packing 9 in the descending process, rides on the pedestal 7 and separates from the packing 9. After the piston 6 was completely lowered, the can body A was taken out and the work was completed.

Although the buckling is detected by the acoustic sensor in this example, the buckling is not limited to the acoustic sensor as long as the buckling can be detected as a physical change. For example, the displacement sensor can detect a change in the position of the can bottom recess, and the vibration sensor can detect vibration during buckling.

The hardness of the packing 9 is appropriately determined mainly by the angle of the reduced diameter portion of the can bottom of the inspected can. In the case of a can having a reduced diameter portion angle of 45 ° as in this example. , Those having a durometer hardness (JIS) of 70 to 80 ° are preferable,
The can does not bite into the packing and deforms the reduced diameter portion, and air leakage can be reliably prevented.

[0051]

[Second Embodiment] In contrast to the first embodiment, this embodiment shows that the hollow shaft moves up and down and the cylindrical sleeve is in a fixed position.

FIG. 3 shows the structure before measurement, and FIG. 4 shows the structure at the time of measurement. In the figure, the same reference numerals and numbers as in Embodiment 1 are
The same parts and portions as in Example 1 are shown.

In this example, the base 1 in Example 1 is replaced by a bottom plate 2.
And a fixed plate 51, which is fixed above the intermediate plate 8 to extend a pair of round bars 4 up and down through holes formed in the fixed plate 51, and a cylindrical sleeve corresponding to the cylindrical sleeve 13. A flange 513C facing outward is provided near the upper end of 513, and the flange 513C is fixed to the fixing plate 51.
It is different from the device of the first embodiment in that it is fixed to the lower surface of the device. 513a is the tip of the cylindrical sleeve 513, which is slightly projected from the upper surface of the fixed plate 51. 51
3b is an annular groove corresponding to 13b of the first embodiment.

With this structure, the piston 6 and the cylindrical sleeve 513 on the piston 6 are fixed, and the bottom plate 2
And, the hollow shaft 5, the outer cylinder 3, the intermediate plate 8, the round bar 4, and the top plate 10, which are the upper structures thereof, move up and down integrally.

In the operation of this device, the air supply means 1
When air is ejected from 6, the piston 6 is fixed, and as a reaction, the bottom plate 2 and its entire upper structure start descending. Thus, the can body A descending together with the descending hollow shaft 5 has the reduced diameter portion 35 of the cylindrical sleeve 513.
When it contacts the inclined surface 591 of the packing 59 (corresponding to the packing 9 in the first embodiment), it is held by the cylindrical sleeve 513 and stops descending. However, the other movable members including the hollow shaft 5 continue to descend until the lower surface of the top plate 10 hits the tip 513a of the cylindrical sleeve 513. The lower surface of the top plate 10 is the tip 51 of the cylindrical sleeve 513.
FIG. 4 shows a state in which the vehicle hits 3a.

After that, the blowing of air, the method of inspection, etc. are the same as those described in the first embodiment, and the description thereof will be omitted. When returning from the state of FIG. 4 to FIG. 3, when air is jetted from the air supply means 17 toward the piston 6, the movable part is raised with the top plate 10 at the top as a reaction, and Return to position.

Since the bottom plate 2, the intermediate plate 8 and the top plate 10 move up and down as the hollow shaft 5 moves up and down, the air supply means 1
The piping connected from 2, 16 and 17 needs to be flexible. In addition, in the first embodiment, the can detection sensors 20 and 20 'attached to the round bar 4 need to be attached to other appropriate places so as not to interfere with the fixing plate 51 when moving up and down.

[0058]

In the conventional apparatus, the can to be inspected is inserted into the mandrel and inspected. Therefore, the can body having the neck portion is
It cannot be inspected as it is, but if you try to inspect by force,
Although the wasteful work of cutting the neck portion was required, in the present invention, the can body is inspected in the upright state without inserting it into the mandrel or the like, so that the original trim can as well as the neck is formed. Even a can can be inspected as it is,
Can immediately respond to quality control at the manufacturing site.

Further, since the pressure resistance value of the final product, the neck can, can be directly measured, the work of correcting the pressure resistance value as in the case of the trim can measurement is unnecessary, and a highly reliable pressure resistance value can be obtained.

In the conventional device, the can body inserted in the mandrel needs to be fixed by the tightening means from the outside so as not to be blown off by the pressurized air jetted from below, and its operation requires time and skill. However, in the present invention, the reduced diameter portion of the can body is held on the packing of the cylindrical sleeve, and the entire can is sealed by the cylindrical sleeve, the packing and the top plate, and blown from above. Since the air acts to press the can body against the packing more strongly,
The tightening means that requires manual adjustment is not required, and the inspection can be performed easily.

In addition, if the distance between the packing and the tip of the cylindrical sleeve is set according to the dimension of the can having the highest can height among the cans to be inspected, the can bodies of different can heights can be measured without adjustment. ..

[Brief description of drawings]

FIG. 1 is a front sectional view showing a state before measurement in an example of carrying out the present invention,

FIG. 2 is a front sectional view showing a state at the time of measurement,

FIG. 3 is a front sectional view showing a state before measurement in another embodiment,

FIG. 4 is a front sectional view showing a state at the time of measurement,

FIG. 5 is a partial cross-sectional explanatory view of an example of a pressure-molded two-piece can having a neck formed thereon;

6 is an enlarged view of a Y portion of FIG.

FIG. 7 is a view similar to FIG. 6, showing another example of the reduced diameter portion of the can bottom,

FIG. 8 is a perspective view showing a main part of a conventional device,

9 is a schematic sectional view taken along line IX-IX in FIG.

FIG. 10 is a schematic plan view of a tightening mechanism before tightening on the outside of the can body.

FIG. 11 is a schematic plan view of the tightening mechanism after tightening.

[Explanation of symbols]

A ... Pressure-resistant two-piece can 1 ... Base plate 2 ... Bottom plate 3 ... Outer cylinder 4 ... Round bar 5 ... Hollow shaft 7 ... Pedestal 71 ... Protrusion 6 ... Piston 13, 513 ... Cylindrical sleeve 9, 59 ... Rubber packing 10 ... Top plate 12 ... Air supply means 18 ... Acoustic sensor 19 ... Pressure sensor D ... Distance from tip of cylindrical sleeve to rubber packing d ... Distance from rubber packing to reduced diameter of can bottom of can on base C ... Sealed chamber 32 ... Can bottom 33 ... Can bottom recess 33 '... Buckled recess 35 ... Reduced diameter portion 37 ... Neck portion 51 ... Fixing plate.

Claims (6)

[Claims] 1. A pressure value inside a can of a two-piece can having a can bottom having a can bottom recess that is recessed toward the inside of the can and a reduced diameter portion around the can is kept closed and pressurized. Is continuously measured by a pressure sensor, and the electrical change is detected by an electrical sensor when the can bottom concave part is reversed to the outside of the can.The internal pressure value immediately before reversal is detected by the electric sensor. In addition, the inspection device that determines whether the pressure resistance value is within an allowable range by comparing the pressure resistance value with a predetermined reference value, and a projection that fits in the can bottom recess of the can body seated upright. A hollow shaft provided with a pedestal at the tip, and a cylindrical sleeve concentrically outside the hollow shaft and having an inner diameter that is not smaller than the larger of the flange outer diameter of the can body and the can body diameter. It may be similar to the height of the measured can from the tip of the cylindrical sleeve. Is a cylindrical sleeve in which an annular packing contacting the outer surface of the reduced diameter portion of the can body is fixedly provided on the inner peripheral surface of the cylindrical sleeve at a distance more than that, and the hollow shaft and the cylindrical sleeve. An elevating device that supports the can body by the packing of the cylindrical sleeve by relative movement with the sleeve and relatively moves in the can axial direction, and from the packing of the cylindrical sleeve to the reduced diameter portion of the can body on the pedestal. And the top plate provided above the pedestal with a distance not less than the sum of the above distance and the distance by which the can bottom recess can be inverted to the outer surface of the can without being obstructed by the pedestal 7. A can bottom pressure resistance test of a pressure resistant two-piece can, comprising: an air supply means attached to the inside of the can to be inspected, which is sealed by the top plate and the cylindrical sleeve. apparatus. 2. The inspection apparatus according to claim 1, wherein the hollow shaft is fixed and the cylindrical sleeve moves up and down. 3. The inspection apparatus according to claim 1, wherein the cylindrical sleeve is fixed, and the hollow shaft moves up and down. 4. The inspection apparatus according to claim 1, wherein an electric sensor for detecting a physical change amount due to the reversal of the can bottom recess toward the outer surface of the can is provided below the pedestal and inside the hollow shaft. 5. The inspection apparatus according to claim 4, wherein the electrical sensor is an acoustic sensor, a vibration sensor, or a displacement sensor. 6. When the tip of the cylindrical sleeve contacts the lower surface of the top plate, the tip of the cylindrical sleeve enters the tip of the cylindrical sleeve, and along with the packing and the cylindrical sleeve, the can body on the packing is shielded from the atmosphere. The inspection device according to claim 1, 2 or 3, wherein a lid member for forming a closed chamber is provided on the lower surface of the top plate.