Body making machine and method of operating a body making machine to mitigate the effects of tool wear, damage and / or misalignment

Abstract

A body making machine for producing can bodies from cups. The body making machine includes: a ram configured to reciprocate along an axis; a punch mounted on the ram; and a tool kit, the tool kit including a bracket and a plurality of tools located in the bracket, the plurality of tools being used to stretch and thin the cup mounted on the punch during the forward stroke of the ram. The body making machine further includes: a backing plate fixed to the body making machine; an adapter plate fixed to the backing plate and a stripper assembly and a clamping mechanism, the stripper assembly being fixed to the adapter plate and used to remove the can body from the punch during the return stroke of the ram, and the clamping mechanism being used to bias the tool against the front end face of the adapter plate. The body making machine further includes one or more load cells, the one or more load cells being located in or on the adapter plate and configured to generate one or more output signals, the output signals being indicative of an axial force applied to the tool as the cup passes through the tool.

Description

Technical Field

[0001] The present invention relates to monitoring of body making machines. In particular, the present invention relates to apparatus and methods for monitoring forces acting on components in a body making machine tool kit while the body making machine is operating. Background Art

[0002] In a known body-making machine that produces thin-walled metal two-piece can bodies by a "drawing and wall-ironing" (DWI) process, a metal cup is supplied to the body-making machine and carried by a punch on the end of a ram through a series of dies to produce a can body of the desired size and thickness. The series of dies may include a redrawing die, which is used to reduce the diameter of the cup and extend the side walls of the cup, and one or more ironing dies, which are used to iron the cup can wall into a can body. The area or bracket of the body-making machine frame where the dies are located is called a "tool kit." The can body carried on the punch may eventually come into contact with a bottom forming tool or "domer" to form a shape such as a dome on the bottom of the can. An exemplary body-making machine is described in WO9934942.

[0003] Can making machines typically run at high speeds for long periods of time, producing in excess of about 300 to 400 can bodies per minute. However, the quality of the can bodies produced can vary greatly over time due to changes in, for example, alignment of machine components, coolant temperature and flow rate, lubrication of the machine, and / or the quality of the incoming cup (e.g., due to variations in the quality of the metal coil from which the cup is made).

[0004] In the DWI process, the metal is subjected to loads as the punch forces it through the ironing die. However, the magnitude and distribution of these loads can vary both during and from stroke to stroke, causing variations in the quality of the cans produced. For example, friction and general wear can cause the alignment of the ram to vary slightly over time. In addition, high-speed reciprocating rams typically experience at least some vibration due to the impact of the ram on the can and the variable "droop" of the ram as it moves to and from its fully extended position.

[0005] As another example, when the ram carries the can into contact with the dome, any misalignment can cause the end of the can to split, especially when the can is made of aluminum. If the misalignment is slight, the split (sometimes called a "smile") may not be immediately visible to the naked eye, but once the can is filled, the split may cause the can to burst. This may not occur until after the full can is purchased.

[0006] Poor quality cans can result in waste and downtime in can production. This may occur, for example, because the canning machine itself must be realigned or repaired, or because other machines on the line are adversely affected by the poor quality cans being produced. Unfortunately, the high-speed, high-volume nature of the canning industry means that lost production time can be very costly to producers.

[0007] Traditionally, alignment and realignment of a bodymaking machine has been a complex and time-consuming process that has been laboriously performed by skilled operators (who are often in short supply) only after a serious problem has occurred. When a bodymaking machine is installed, the ram and its drive components are typically secured in place on the bodymaking machine frame. This aligns the axis of the ram with the main axis of the bodymaking machine. Other components, including, for example, the redraw and ironing dies and dome pieces, are then aligned with the ram. Summary of the invention

[0008] According to a first aspect of the present invention, there is provided a body making machine for producing a can body from a cup. The body making machine comprises: a ram configured to reciprocate along an axis; a punch mounted on the ram; and a tool kit, the tool kit comprising a bracket and a plurality of tools located in the bracket, the tools being used to stretch and thin the cup mounted on the punch during the forward stroke of the ram. The body making machine further comprises a backing plate fixed to the body making machine, an adapter plate fixed to the backing plate, and a stripper assembly and a clamping mechanism, the stripper assembly being fixed to the adapter plate and being used to remove the can body from the punch during the return stroke of the ram, the clamping mechanism being used to bias the tool against the front end face of the adapter plate. The body making machine further comprises one or more load cells, the one or more load cells being located in or on the adapter plate and being configured to generate one or more output signals, the one or more output signals being indicative of an axial force applied to the tool as the cup passes through the tool.

[0009] The term "axial force" means a force having a component along the axis along which the ram reciprocates.

[0010] The body making machine may include an encoder configured to provide a measurement of the position of the ram at one or more times during each reciprocating motion. The encoder may be a linear encoder. Alternatively, the encoder may be a rotary encoder configured to be rotated by a shaft for driving the ram.

[0011] One or more of the load cells may be piezoelectric load cells.

[0012] The one or more load cells may include more than one load cell, the load cells being angularly spaced equidistant from one another about the axis.

[0013] The bodymaking machine may include a processor configured to adjust one or more operating parameters of the bodymaking machine, such as a rate of reciprocation of the ram, in response to one or more output signals.

[0014] The adapter plate may be secured to the backing plate by one or more pre-tensioning bolts, each of which passes through a respective one of the load cells to secure the load cells between the adapter plate and the backing plate.

[0015] The stripper assembly may include a radial deflection monitor for detecting misalignment of the ram and / or punch relative to the axis.

[0016] The radial deflection monitor may include a bore configured to allow passage of the punch and ram and one or more eddy current sensors spaced about the bore.

[0017] According to a second aspect of the invention, there is provided an apparatus for retrofitting a body making machine. The body making machine comprises: a ram configured to reciprocate along an axis; a punch mounted on the ram; a tool kit comprising a bracket and a plurality of tools located in the bracket, the plurality of tools being used to stretch and thin a cup mounted on the punch during a forward stroke of the ram; a backing plate fixed to the body making machine; an adapter plate fixed to the backing plate; a stripper assembly, the stripper assembly being used to remove a can from the punch during a return stroke of the ram; and a clamping mechanism, the clamping mechanism being used to bias the tool against a front end face of the adapter plate. The apparatus comprises: a replacement adapter plate, the replacement adapter plate being used to be fixed to the backing plate in place of the body making machine's adapter plate; and one or more load cells, the one or more load cells being located in or on the replacement adapter plate and being configured to generate one or more output signals, the one or more output signals being indicative of an axial force applied to the tool as the cup passes through the tool.

[0018] The alternative adapter plate may include a stripper assembly including a radial deflection monitor for detecting misalignment of the ram and / or punch relative to the axis. The radial deflection monitor may include a hole configured to allow passage of the punch and ram and one or more eddy current sensors spaced around the hole.

[0019] According to a third aspect of the invention, there is provided a method of calibrating the apparatus of the second aspect after it has been retrofitted to a body making machine. The method comprises mounting a calibration fixture in a carriage of the body making machine, the calibration fixture comprising one or more reference load cells, the one or more reference load cells being configured to produce one or more output signals indicative of an axial force applied to a tool located in the carriage. Using a clamping mechanism of the body making machine, an axial force is applied to the tool and the one or more reference load cells. Using the respective one or more output signals of the one or more reference load cells, a calibration coefficient or calibration function is determined, whereby the output signals produced by the one or more load cells of the apparatus estimate the force on the one or more tools.

[0020] According to a fourth aspect of the invention, there is provided a method of operating a body making machine to mitigate the effects of tool wear, damage and / or misalignment during can production. Each can is formed by pushing a cup mounted on a punch of a ram that reciprocates along an axis through a tool included in a bracket of a body making machine tool kit. The method includes obtaining an output signal from one or more load cells indicating an axial force applied to the tool as the cup passes through the tool, the load cells being located in or on an adapter plate attached to a backing plate fixed to the body making machine. The output signal is processed to obtain data indicating wear, damage and / or misalignment of one or more tools relative to the ram. Based on the data, one or more operating parameters of the body making machine, or one or more operating parameters of another component of the production line in which the body making machine is located, are adjusted to mitigate the effects of wear, damage and / or misalignment of one or more tools relative to the ram.

[0021] The one or more operating parameters may include one or more of the following parameters:

[0022] the rate at which cans are produced;

[0023] The operating temperature of the tool kit;

[0024] the rate or temperature at which coolant is supplied to the tool package;

[0025] the rate at which lubricant is supplied to the tool kit; and

[0026] The position of the dome relative to the axis of the ram.

[0027] The one or more operating parameters may include parameters of components upstream or downstream of the bodymaker line, such as a cup press.

[0028] The method may include removing the can from the punch during a return stroke of the ram using a stripper secured to the adapter plate.

[0029] The stripper can be set in a stripper assembly including a radial deviation monitor, the method further including using the radial deviation monitor to obtain an output signal indicating the position of the slide and / or punch perpendicular to the axis, and then adjusting the one or more operating parameters based on the data and the output signal obtained from the radial deviation monitor. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 A schematic perspective view of a can making machine is shown;

[0031] Figure 2 for Figure 1 A schematic cross-sectional perspective view of a tool kit for a body making machine;

[0032] Figure 3 for Figure 1 Another schematic cross-sectional perspective view of a can making machine;

[0033] Figure 4 is a schematic perspective rear view of the adapter plate and the stripper assembly;

[0034] Figure 5 for Figure 4 a schematic cross-sectional side view of an adapter plate and stripper assembly;

[0035] Figure 6 for Figure 4 A schematic perspective front view of an adapter plate and a stripper assembly;

[0036] Figure 7 is a schematic cross-sectional side view of a load cell of the tool kit mounted between an adapter plate and a backing plate; and

[0037] Figure 8 A flow chart of a method of operating a body making machine to mitigate the effects of tool wear, damage and / or misalignment during can body production. DETAILED DESCRIPTION

[0038] Figure 1A schematic perspective view of a modular body making machine 101 for making can bodies from cups stretched from sheet metal. The body making machine 101 includes a base 102 supporting a machine bed 103 having a reference surface and a ram assembly 105. The ram assembly 105 includes a reciprocating ram 106 with a punch (not shown) mounted on one end. During the forward stroke of the body making machine 101, the punch contacts a cup (not shown) on the ram path within a tool bag 107 located on the reference surface. The punch pushes the cup through a redraw die (not shown) contained within the tool bag 107 to form an elongated can body. The can body is carried on the punch to contact a bottom forming tool 108 contained by a dome module 109, thereby forming a shape such as a dome on the bottom of the can. During the return stroke of the body making machine 101, the can body is removed from the punch by a stripper (not shown) in the tool bag 107. The tanks are transported away from the ram axis by the tank discharge turret 110 of the feed-discharge module 111 located between the tool kit 107 and the dome module 109.

[0039] The tool kit 107 also includes a re-stretch sleeve module 112, which is located in front of the re-stretch die (not shown) for positioning the cup during the re-stretching process. The re-stretch sleeve module 212 includes a bearing 113 with a cup locator (not shown) for receiving the cup from the feed mechanism 114 of the feed-discharge module 111. The bearing 113 supports a reciprocating re-stretch sleeve 115, which is coaxially aligned with the slide and has a center hole that allows the punch to pass through. The rear end of the re-stretch sleeve 115 is connected to a re-stretch slide 116, which is driven to reciprocate by a pair of push rods 117a, 117b located on opposite sides of the slide 106. Before the punch contacts the can body, the re-stretch sleeve 115 enters the open end of the cup, forcing the cup to contact the re-stretch die. As the punch pushes the cup through the hole of the redraw die, which is smaller in diameter than the cup, the redraw sleeve 115 holds the cup firmly in place against the redraw die. As the cup is drawn through the redraw die by the punch, the diameter of the cup decreases and the sidewalls lengthen. The tool kit 107 may also include one or more ironing dies or other tools for forming the can body after the redraw die. The punch then carries the elongated cup out of the redraw sleeve module and through the remaining ironing dies and tools.

[0040] Figure 2 and Figure 3 It is a cross-sectional perspective view of the tool kit 107 , which includes a shell 219 and a stripper assembly 221 , in which a bracket 220 is disposed. The stripper assembly 221 is connected to a backing plate 223 via an adapter plate 225 , and the backing plate 223 is connected to the shell 219 and provides a rear wall of the tool kit 107 . Figure 2The dashed line A-A' in FIG. 2 shows the axis along which the punch (not shown) travels. The bracket 220 has a cylindrical inner surface and a wear strip 229 for supporting the ironing die (not shown) and the spacer ring (226A, B) in the housing 219. The ironing die (not shown) is mounted on the front face of the housing 219 and forms an entrance to the housing 219 into which the punch moves during the forward stroke of the ram (106).

[0041] The stripper assembly 221 includes a stripper 233 mounted within a stripper housing 235, which is connected to the adapter plate 225. The stripper 233 includes stripper fingers extending radially inward (i.e., toward the axis A-A'). During the forward stroke of the ram 106, the can carried on the punch deflects the stripper fingers as it moves through the stripper 233. During the return stroke, i.e., away from the bottom forming tool 108, the stripper fingers prevent the can from returning with the punch, and the can is stripped from the punch and then removed from the body making machine 101 with the aid of the can discharge turret 210. In other embodiments not shown herein, the can can be removed from the body making machine 101 by pressurized air (alternatively, pressurized air can also be used to assist the stripper in removing the can).

[0042] The adapter plate 225 is located between the backing plate 223 and the tool kit housing 219. The adapter plate 225 includes three load cells 237A-C (see Figures 4 to 6 ), each load cell has an axis oriented along axis A-A' toward bracket 220, thereby measuring the force generated when the punch passes through the die. In this example, load cells 237A-C are piezoelectric load cells, each of which generates an electrical signal when compressed along its axis (which is preferably aligned parallel to axis A-A').

[0043] Figure 4 The rear end face of the adapter plate 225 is shown with the backing plate 223 (and the rest of the tool kit 107) removed so that each of the three load cells 237A-C is visible. The annular body 301A of each load cell 273A-C is located in a recess formed in the edge and rear end face of the adapter plate 225 (i.e., the surface of the adapter plate 225 farthest from the tool kit bracket 220). In this example, each recess is shaped to accommodate a cable connection to the side of the annular body 301A. The load cell 237A also includes a pre-tensioning bolt 301B that passes through the adapter plate 225, through the center of the annular body 301A and into the backing plate 223. The cylindrical body 301A protrudes from the recess so that it contacts the backing plate 223 through the small gap between the adapter plate 225 and the backing plate 223 (see Figure 7The pre-tightening bolts 301B are used to bias the adapter plate 225 toward the backing plate 223 so that the annular body 301A is compressed therebetween. Applying a force to the adapter plate 225 in the direction of the backing plate 223 will cause the annular body 301A to be further compressed (i.e., the pre-tightening bolts 301B do not prevent the adapter plate 225 from moving toward the backing plate 225).

[0044] Figure 5 A vertical section through the adapter plate 225 and the stripper assembly 221 along the axis AA' is shown.

[0045] Figure 6 A perspective view of the front face of the adapter plate 225 (ie, the face closest to the tool kit carrier 220) is shown.

[0046] Figure 7 The adapter plate 225 is shown bolted to the backing plate 223 using pre-tension bolts 301B which pass through the cylinder 301A of the load cell 237A. The cylinder 301A is compressed between the rear end face of the adapter plate 225 and the front end face of the backing plate 223.

[0047] exist Figures 4 to 7 In the particular embodiment shown, the stripper housing 235 includes four eddy current sensors (although one or more than four eddy current sensors may be used) spaced about a central hole through which the ram moves for monitoring radial deflection of the punch / ram. The radial deflection data from the eddy current sensors can be correlated with the force data obtained from the load cells 237A-C. This correlation helps identify the cause of radial misalignment between the ram / punch and the tool kit components. For example, an abnormally large force generated when the punch passes through one of the dies may be caused by misalignment of the ram / punch or by misalignment of the die itself; these two possibilities can be distinguished from each other using the radial deflection data.

[0048] Back to Figure 2 and Figure 3 , when the punch travels through the bracket 220 (i.e., Figure 2 As shown in FIG. 2 (left to right in FIG. 2 ), the can is pushed through the re-stretch die and the ironing die, which generates longitudinal forces that are transmitted through the dies and spacer rings to the load cells 237A-C. Thus, the time-varying signals generated by the load cells 237A-C provide a measurement of the longitudinal forces acting on the dies as the can sidewall is stretched and / or ironed.

[0049] The load cells 237A-C may be arranged equiangularly about the axis A-A' to provide optimal sensitivity. In order to provide sufficient spatial detail, it is preferred to have at least three load cells 237A-C, and the maximum number of load cells 237A-C is limited only by cost and available space within the adapter plate 225. Other types of load cells 237A-C, such as capacitive load cells, may also be used instead of or in addition to the piezoelectric load cells.

[0050] The adapter plate 225 can be retrofitted to an existing body making machine without modifying the tool kit, such as by replacing the existing adapter plate.

[0051] Because the load cells 237A-C are located outside of the bracket 220, force measurements can be made without the need to reconfigure or replace components (tooling) in the bracket 220. For example, while it is in principle possible to install a fixture with the load cells 237A-C in place of one of the spacer rings, this would require the fixture to be manufactured to high tolerances and multiple versions of the fixture might be required, depending on which molds are included in the tooling kit. Such an arrangement might also adversely affect the cooling provided to the molds. Including the load cells 237A-C within the bracket 220 might also be problematic because installation and removal of the assembly from the bracket 220 might damage the load cells 237A-C.

[0052] Although force measurements may be made with a single load cell 237A, it is preferred to have more than one sensor in order to obtain information about how the forces acting on the die are spatially distributed. For example, multiple load cells 237A-C may be used to determine that the relative alignment between the ram / punch and one or more dies requires correction, such as using an iterative process in which the forces measured by each load cell 237A-C are compared and the alignment of the ram and / or die is changed until the forces are balanced and / or until each measured force is minimized. In practice, this process may be performed using a computer device (not shown) that includes an analog-to-digital converter (ADC) to process the time-varying electrical signals generated by the load cells 237A-C and then generate a graphical display of the forces or force readouts that can be viewed by an operator who is making the necessary adjustments.

[0053] In some cases, the computer device may be configured to detect when the forces exceed a threshold and / or if there is an imbalance in the forces measured that exceed the threshold (e.g., one of the measured forces is greater than the other), and then respond by generating a visual or audible alarm and / or stopping operation of the body maker 101. The computer device may also control one or more operating parameters of the body maker 101 to ensure that it operates safely and efficiently. For example, the computer device may reduce the repetition rate of the body maker 101 once a problem begins to occur.

[0054] The time-varying measurements obtained from the load cells 237A-C may be recorded (e.g., stored in a database) so that gradual changes in alignment caused by wear and vibration may be monitored. The time resolution provided by the ADC is sufficient to resolve the time variations in the forces measured during a single stroke. This data may be associated with the longitudinal position data of the ram during each stroke (i.e., data indicating the movement of the ram along the axis A-A'). For example, this data may be obtained from a high-resolution rotary encoder that is rotated by a shaft used to drive the reciprocating ram, or from a high-resolution linear encoder that directly measures the longitudinal position of the ram. By associating the force measurements with the position data, specific features in the force measurements may be attributed to the ram passing through specific components of the tool kit, for example, a specific mold may be identified as poorly aligned or damaged, or the wear of each mold may be estimated from the total force on each mold integrated over a large number of strokes. This analysis may be performed automatically by a computer device, which may generate a warning signal or alarm indicating that one or more molds need to be realigned or replaced. The number of strokes may also be recorded so that the measured force data may be associated with a specific can or cans produced by the bodymaker 101, for example, so that a specific can or batch of cans may be demonstrated to be free of defects or otherwise prevented from being shipped to a customer.

[0055] The load cells 237A-C do not necessarily need to be calibrated, as useful information can still be obtained from the relative forces measured by each load cell 237A-C (e.g., detecting changes in the relative alignment of the parts over time). However, calibration of the load cells 237A-C can allow a more accurate model of the forces acting on the mold to be constructed, thereby allowing more sophisticated processing of the measurements and earlier detection of potential problems. Calibration herein refers to the conversion of the electrical signals generated by the load cells 237A-C and the actual longitudinal forces acting on the tool kit parts. This may involve determining a mathematical conversion function that takes the electrical signal as an input and provides a corresponding force as an output. In some cases, the function may include a multiplication factor that scales the electrical signal. Generally, calibration is required for accurate measurements because the ratio of the forces transmitted to the load cells 237A-C will vary depending on how the adapter plate 225 is mounted, and / or because the transmission of forces from the mold may vary depending on how the tool kit is configured, such as what kind of "preload" is applied to the tool kit (see below).

[0056] To calibrate load cells 237A-C, a fixture including one or more reference load cells (not shown) may be mounted in bracket 220 (e.g., in place of one of the spacer rings or ironing dies). A load is then applied to the reference load cell along axis A-A', and the electrical signals generated by load cells 237A-C and the reference load cell are measured. A transfer function is then determined from the measured signals, such as by fitting a polynomial or spline interpolation function to the reference signal plotted against the load cell signal. The loads applied to the reference load cell and load cells 237A-C may be applied by tool kit fixture 241 (see Figure 2 ), the tool kit clamp 241 provides a compressive load between the adapter plate 225 and the front wall 239 of the housing 219. A certain proportion of this load (referred to as the "preload") is applied when the body making machine 101 is operated to securely hold the tool kit components in place. Therefore, the calibration of the load cells 237A-C can be used to account for (i.e., compensate for) differences in preload between body making machines. The calibration of the load cells 237A-C also allows compensation for the proportion of the longitudinal load that bypasses the load cells 237A-C via the preload bolts 301B.

[0057] The force measurements obtained from the load cells 237A-C during can production may be analyzed using machine learning, analytics, and / or artificial intelligence techniques to determine how the operation of the bodymaking machine can be improved, such as by adjusting one or more operating parameters of the bodymaking machine. For example, an evolutionary algorithm (or other type of optimization algorithm) may be used to change operating parameters of the bodymaking machine based on a fitness based on the measured forces, such as a fitness that penalizes measured forces that exceed a predetermined threshold and / or forces measured by the load cells 237A-C that differ from each other by a predetermined threshold or relative ratio.

[0058] The operating parameters of the bodymaker provided to the algorithm may include one or more of the following: the rate at which cans are produced (the set speed of the bodymaker), the operating temperature of the tooling, the rate at which coolant is supplied to the tooling, the rate at which lubricant is supplied to the tooling, and the position (alignment) of the dome relative to the ram axis. The algorithm may also take as input other types of data, such as the time since the bodymaker was last serviced or reconfigured, the number of cans produced using the current set of molds, and / or measurements of the quality of the raw material, such as the thickness or weight of the cups supplied to the bodymaker.

[0059] Feedback control can also be used to adjust one or more bodymaker operating parameters to compensate for changes in the bodymaker over time due to wear or movement of bodymaker components. For example, a proportional-integral-derivative (PID) controller can be used to change one or more bodymaker operating parameters to minimize an error signal determined from the measured force.

[0060] Figure 8 The steps involved in a method of operating a body making machine to mitigate the effects of tool wear, damage and / or misalignment during can production are shown, for example using the body making machine described above. A first step 801 includes obtaining an output signal from one or more load cells 237A-C, the output signal indicating an axial force applied to the tool by a cup as it passes through the tool, the load cells being located in or on an adapter plate 225 attached to a body making machine backing plate 223. The output signal is then processed 802 to obtain data indicative of wear, damage and / or misalignment of one or more tools relative to the ram 106. For example, this may involve determining that the force applied by the cup to the tool exceeds a threshold value, or that a difference or ratio of output signals obtained from two or more load cells exceeds a predetermined threshold value. Based on the data, one or more operating parameters of the body making machine or one or more operating parameters of another component of the production line in which the body making machine is located are adjusted 803 to mitigate the effects of wear, damage and / or misalignment of one or more tools relative to the ram 106. As described above, this process may be repeated 804 iteratively in a feedback loop.

[0061] It will be appreciated by those skilled in the art that various modifications may be made to the above-described embodiments without departing from the scope of the present invention.

Claims

1. A can making machine for producing can bodies from cup-shaped articles, the machine comprising: a ram configured to reciprocate along an axis; A punch, which is mounted on the ram; a tool kit including a carriage and a plurality of tools located in the carriage, the tools being used to stretch and thin a cup mounted on a punch during an advance stroke of the ram; a backing plate, which is secured to the body making machine; an adapter plate secured to the backing plate; a stripper assembly secured to the adapter plate and used to remove the can from the punch during the return stroke of the ram; a clamping mechanism for biasing the tool against the front end face of the adapter plate; one or more load cells located in or on the adapter plate and configured to generate one or more output signals indicative of an axial force applied to the tool by the cup as it passes through the tool; an encoder configured to provide measurements of the ram position at multiple times during each reciprocating motion; as well as A computer device is configured to correlate one or more output signals indicative of an axial force exerted on a tool with a ram position at a plurality of times.

2. The body making machine according to claim 1, wherein: The encoder is a linear encoder.

3. The body making machine according to claim 1, wherein: The encoder is a rotary encoder configured to be rotated by a shaft for driving a ram.

4. The body making machine according to claim 1, wherein: One or more load cells are piezoelectric load cells.

5. The body making machine according to claim 1, wherein: The more than one load cell is angularly spaced equidistantly from one another about the axis.

6. The bodymaking machine of claim 1, comprising a processor configured to adjust one or more operating parameters of the bodymaking machine in response to the one or more output signals.

7. The body making machine according to claim 6, wherein: The one or more operating parameters of the bodymaker include a rate of reciprocation of the ram.

8. The body making machine according to claim 1, wherein: The adapter plate is fixed to the backing plate by one or more pre-tightening bolts, each of which passes through a respective one of the load cells to fix the load cell between the adapter plate and the backing plate.

9. The body making machine according to claim 1, wherein: The stripper assembly includes a radial deflection monitor for detecting misalignment of the ram and / or punch relative to the axis.

10. The body making machine according to claim 9, wherein: The radial deflection monitor includes a bore configured to allow passage of a punch and a ram and one or more eddy current sensors spaced about the bore.

11. A method of operating a body making machine according to any preceding claim, the method mitigating the effects of tool wear or damage during the production of can bodies, each can body being formed by pushing a cup mounted on said punch of said ram reciprocating along an axis through a tool contained in said carriage of said tool pack of the body making machine, said method comprising: obtaining a plurality of output signals from the one or more load cells, the plurality of output signals being indicative of an axial force applied to the tool as the cup passes through the tool, the one or more load cells being located in or on an adapter plate attached to the backing plate, the backing plate being secured to the body making machine; obtaining measurements of the ram position at multiple times during each reciprocating motion from an encoder; correlating, using a computer device, an output signal indicative of an axial force applied to a tool with a ram position at a plurality of times to obtain data indicative of wear or damage to one or more tools; One or more operating parameters of the bodymaking machine, or one or more operating parameters of another component of a production line in which the bodymaking machine is located, are adjusted based on the data to mitigate the effects of wear or damage to one or more tools.

12. The method according to claim 11, wherein: The one or more operating parameters include one or more of the following parameters: the rate at which cans are produced; The operating temperature of the tool kit; the rate or temperature at which coolant is supplied to the tool package; the rate at which lubricant is supplied to the tool kit; as well as The position of the dome relative to the axis of the ram.

13. The method according to claim 11, wherein: The one or more operating parameters include parameters of components upstream or downstream of the bodymaker production line.

14. The method of claim 11 including removing the can from the punch during the return stroke of the ram using a stripper secured to the adapter plate.

15. The method according to claim 14, wherein: The stripper is arranged in a stripper assembly including a radial deviation monitor, and the method further includes using the radial deviation monitor to obtain an output signal indicating the position of the slide and / or punch perpendicular to the axis, and then adjusting the one or more operating parameters based on the data and the output signal obtained from the radial deviation monitor.

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